WorldWideScience

Sample records for approach control

  1. Newer approaches to malaria control.

    Science.gov (United States)

    Damodaran, Se; Pradhan, Prita; Pradhan, Suresh Chandra

    2011-07-01

    Malaria is the third leading cause of death due to infectious diseases affecting around 243 million people, causing 863,000 deaths each year, and is a major public health problem. Most of the malarial deaths occur in children below 5 years and is a major contributor of under-five mortality. As a result of environmental and climatic changes, there is a change in vector population and distribution, leading to resurgence of malaria at numerous foci. Resistance to antimalarials is a major challenge to malaria control and there are new drug developments, new approaches to treatment strategies, combination therapy to overcome resistance and progress in vaccine development. Now, artemisinin-based combination therapy is the first-line therapy as the malarial parasite has developed resistance to other antimalarials. Reports of artemisinin resistance are appearing and identification of new drug targets gains utmost importance. As there is a shift from malaria control to malaria eradication, more research is focused on malaria vaccine development. A malaria vaccine, RTS,S, is in phase III of development and may become the first successful one. Due to resistance to insecticides and lack of environmental sanitation, the conventional methods of vector control are turning out to be futile. To overcome this, novel strategies like sterile insect technique and transgenic mosquitoes are pursued for effective vector control. As a result of the global organizations stepping up their efforts with continued research, eradication of malaria can turn out to be a reality. PMID:23508211

  2. Linear Design Approach to a Fuzzy Controller

    DEFF Research Database (Denmark)

    Jantzen, Jan

    1999-01-01

    A ball-balancer, basically an inverted pendulum problem, is stabilised by a linear controller. With certain design choices, a fuzzy controller is equivalent to a summation; thus it can replace the linear controller. It can be claimed, that the fuzzy controller performs at least as well...... as the linear controller, since the linear controller is contained in the fuzzy controller. The approach makes it somewhat easier to design a fuzzy controller....

  3. An approach to optical structures control

    Science.gov (United States)

    Iwens, R. P.; Benhabib, R. J.; Major, C. S.

    1988-01-01

    The stabilization of a large, spaceborne Cassegrain telescope is examined. Modal gain factors and known characteristics of disturbances are used to determine which structural model affect line of sight (LOS) the most and are candidates for active control. THe approach is to: (1) actively control and maintain alignment of optical components; (2) place structural control actuators for optimum impact on the selected modes for active vibration control; and (3) feed back the best available estimate of LOS error for direct LOS control. Local analog loops are used for lower bandwidth control and multivariable digital control for lower bandwidth control. The control law is synthesized in the frequency domain using the characteristic gain approach. Robustness is measured by employing conicity, which is an outgrowth of the positivity approach to robust feedback system design. The feasibility of the design approach will be demonstrated by conducting a lab experiment on a structure similar to a scaled version of the telescope.

  4. Contamination Control: a systems approach

    NARCIS (Netherlands)

    Donck, J.C.J. van der

    2010-01-01

    Contamination influences a wide variety of industrial processes. For complex systems, contamination control, the collective effort to control contamination to such a level that it guarantees or even improves process or product functionality, offers a way for finding workable solutions. Central in th

  5. Control theory: A practical approach

    International Nuclear Information System (INIS)

    Stability and frequency response enhancements can be made to custom manufactured and off-the-shelf power supplies. Combined power converter and magnet loads that result in poor transient response and marginal loop stability due to inadequate phase margin can be corrected with a systematic approach utilizing lead compensation techniques. Using a Venable Systems 350 Frequency Response Analyzer two actual case studies are documented demonstrating a practical approach to stabilizing and enhancing a power supply's performance. A description of the system and conventions are followed by a description of two power supplies with specific deficiencies. The first case study involves a power supply without a dominant pole output capacitor. The next case study involves a power supply driving a highly damped resonant load. The paper is concluded by a discussion of measurements pitfalls

  6. Generic attack approaches for industrial control systems.

    Energy Technology Data Exchange (ETDEWEB)

    Duggan, David P.

    2006-01-01

    This report suggests a generic set of attack approaches that are expected to be used against Industrial Control Systems that have been built according to a specific reference model for control systems. The posed attack approaches are ordered by the most desirable, based upon the goal of an attacker. Each attack approach is then graded by the category of adversary that would be capable of utilizing that attack approach. The goal of this report is to identify necessary levels of security required to prevent certain types of attacks against Industrial Control Systems.

  7. Chaotic satellite attitude control by adaptive approach

    Science.gov (United States)

    Wei, Wei; Wang, Jing; Zuo, Min; Liu, Zaiwen; Du, Junping

    2014-06-01

    In this article, chaos control of satellite attitude motion is considered. Adaptive control based on dynamic compensation is utilised to suppress the chaotic behaviour. Control approaches with three control inputs and with only one control input are proposed. Since the adaptive control employed is based on dynamic compensation, faithful model of the system is of no necessity. Sinusoidal disturbance and parameter uncertainties are considered to evaluate the robustness of the closed-loop system. Both of the approaches are confirmed by theoretical and numerical results.

  8. HYBRID CONTROL APPROACH FOR CONTAINER CRANES

    Institute of Scientific and Technical Information of China (English)

    Wang Xiaojun; Shao Huihe

    2005-01-01

    A hybrid control approach is proposed to achieve the desired performance. Firstly a robust input shaper is designed to reduce the transient vibration and residual vibration of the container efficiently. Then a simple fuzzy logic controller is designed to eliminate the residual vibration completely in order to guarantee the positioning precision. Such a hybrid approach is simple in structure and readily realizable. Simulation results verify the fine performance of this hybrid control approach. It can achieve perfect elimination of residual vibration and concise positioning of the container load, and it is robust to parameter variations (mainly for cable length) and external disturbances.

  9. Flight Test Approach to Adaptive Control Research

    Science.gov (United States)

    Pavlock, Kate Maureen; Less, James L.; Larson, David Nils

    2011-01-01

    The National Aeronautics and Space Administration s Dryden Flight Research Center completed flight testing of adaptive controls research on a full-scale F-18 testbed. The validation of adaptive controls has the potential to enhance safety in the presence of adverse conditions such as structural damage or control surface failures. This paper describes the research interface architecture, risk mitigations, flight test approach and lessons learned of adaptive controls research.

  10. Structural controllability: an undirected graph approach

    CERN Document Server

    Belur, Madhu N

    2010-01-01

    This paper addresses questions regarding controllability for `generic parameter' dynamical systems, i.e. the question whether a dynamical system is `structurally controllable'. Unlike conventional methods that deal with structural controllability, our approach uses an undirected graph: the behavioral approach to modelling dynamical systems allows this. Given a system of linear, constant coefficient, ordinary differential equations of any order, we formulate necessary and sufficient conditions for controllability in terms of weights of the edges in a suitable bipartite graph constructed from % components with equal bipartite cardinality in the differential-algebraic system. % of equations. A key notion that helps formulate the conditions is that of a `redundant edge'. Removal of all redundant edges makes the inferring of structural controllability a straightforward exercise. We use standard graph algorithms as ingredients to check these conditions and hence obtain an algorithm to check for structural controlla...

  11. Systems Approach to Arms Control Verification

    Energy Technology Data Exchange (ETDEWEB)

    Allen, K; Neimeyer, I; Listner, C; Stein, G; Chen, C; Dreicer, M

    2015-05-15

    Using the decades of experience of developing concepts and technologies for verifying bilateral and multilateral arms control agreements, a broad conceptual systems approach is being developed that takes into account varying levels of information and risk. The IAEA has already demonstrated the applicability of a systems approach by implementing safeguards at the State level, with acquisition path analysis as the key element. In order to test whether such an approach could also be implemented for arms control verification, an exercise was conducted in November 2014 at the JRC ITU Ispra. Based on the scenario of a hypothetical treaty between two model nuclear weapons states aimed at capping their nuclear arsenals at existing levels, the goal of this exercise was to explore how to use acquisition path analysis in an arms control context. Our contribution will present the scenario, objectives and results of this exercise, and attempt to define future workshops aimed at further developing verification measures that will deter or detect treaty violations.

  12. Flight Approach to Adaptive Control Research

    Science.gov (United States)

    Pavlock, Kate Maureen; Less, James L.; Larson, David Nils

    2011-01-01

    The National Aeronautics and Space Administration's Dryden Flight Research Center completed flight testing of adaptive controls research on a full-scale F-18 testbed. The testbed served as a full-scale vehicle to test and validate adaptive flight control research addressing technical challenges involved with reducing risk to enable safe flight in the presence of adverse conditions such as structural damage or control surface failures. This paper describes the research interface architecture, risk mitigations, flight test approach and lessons learned of adaptive controls research.

  13. Global approach for hybrid vehicle optimal control

    OpenAIRE

    Scordia, Julien; TRIGUI, Rochdi; DESBOIS-RENAUDIN, Matthieu; JEANNERET, Bruno; BADIN, François

    2009-01-01

    In this paper, we describe the global approach that has been developed at INRETS-LTE for hybrid powertrain sizing, consumption gain evaluation, and optimal control. The procedure is described in the particular case of a two clutch parallel hybrid architecture, but could apply to any other configuration. Firstly the context and the common issues related to this subject are described. Then our global approach is detailed: sizing procedure, offline global optimization process, method for obtaini...

  14. Angular-velocity control approach for stance-control orthoses.

    Science.gov (United States)

    Lemaire, Edward D; Goudreau, Louis; Yakimovich, Terris; Kofman, Jonathan

    2009-10-01

    Currently, stance-control knee orthoses require external control mechanisms to control knee flexion during stance and allow free knee motion during the swing phase of gait. A new angular-velocity control approach that uses a rotary-hydraulic device to resist knee flexion when the knee angular velocity passes a preset threshold is presented. This angular-velocity approach for orthotic stance control is based on the premise that knee-flexion angular velocity during a knee-collapse event, such as a stumble or fall, is greater than that during walking. The new hydraulic knee-flexion control device does not require an external control mechanism to switch from free motion to stance control mode. Functional test results demonstrated that the hydraulic angular-velocity activated knee joint provided free knee motion during walking, engaged upon knee collapse, and supported body weight while the end-user recovered to a safe body position. The joint was tested to 51.6 Nm in single loading tests and passed 200,000 repeated loading cycles with a peak load of 88 Nm per cycle. The hydraulic, angular velocity activation approach has potential to improve safety and security for people with lower extremity weakness or when recovering from joint trauma. PMID:19497821

  15. Predictive Approaches to Control of Complex Systems

    CERN Document Server

    Karer, Gorazd

    2013-01-01

    A predictive control algorithm uses a model of the controlled system to predict the system behavior for various input scenarios and determines the most appropriate inputs accordingly. Predictive controllers are suitable for a wide range of systems; therefore, their advantages are especially evident when dealing with relatively complex systems, such as nonlinear, constrained, hybrid, multivariate systems etc. However, designing a predictive control strategy for a complex system is generally a difficult task, because all relevant dynamical phenomena have to be considered. Establishing a suitable model of the system is an essential part of predictive control design. Classic modeling and identification approaches based on linear-systems theory are generally inappropriate for complex systems; hence, models that are able to appropriately consider complex dynamical properties have to be employed in a predictive control algorithm. This book first introduces some modeling frameworks, which can encompass the most frequ...

  16. The disease management approach to controlling asthma.

    Science.gov (United States)

    Haahtela, T

    2002-02-01

    Asthma has become an important public health issue worldwide and certain groups, such as children, are at particular risk of the disease. Often asthma remains under-diagnosed and under-treated. Despite these worrying trends, the disease management approach to asthma control can help most asthma patients achieve a 'normal' way of life. The increased prevalence and greater diagnostic awareness of asthma have placed increased demands on healthcare resources, but effective asthma control can minimize the personal, social and economic burdens of asthma. Early diagnosis and immediate anti-inflammatory treatment is the first step in gaining control of symptoms. A stepwise approach is then used to classify asthma severity and treatment, with the number and frequency of medications increasing (step up) as asthma severity increases and decreasing (step down) when asthma is under control. This stepwise approach to asthma management necessitates regular review of treatment once asthma is under control. However, effective asthma management is dependent on successful patient education, adherence to prescribed medication and good doctor patient partnerships. Current treatment guidelines recommend the use of a written asthma management plan that should be agreed between the doctor and patient. These plans should cover all aspects of asthma treatment, including prevention steps for long-term control and action steps to stop attacks once a worsening in asthma has been recognized. This comprehensive approach to asthma management increases the likelihood of achieving asthma control, which in turn reduces the need for emergency visits to the hospital or clinic and reduces the limitations on physical activity previously imposed by the condition.

  17. A Modular Approach to Redundant Robot Control

    International Nuclear Information System (INIS)

    This paper describes a modular approach for computing redundant robot kinematics. First some conventional redundant control methods are presented and shown to be 'passive control laws', i.e. they can be represented by a network consisting of passive elements. These networks are then put into modular form by applying scattering operator techniques. Additional subnetwork modules can then be added to further shape the motion. Modules for obstacle detection, joint limit avoidance, proximity sensing, and for imposing nonlinear velocity constraints are presented. The resulting redundant robot control system is modular, flexible and robust

  18. Controllable Load Management Approaches in Smart Grids

    Directory of Open Access Journals (Sweden)

    Jingshuang Shen

    2015-10-01

    Full Text Available With rapid smart grid technology development, the customer can actively participate in demand-side management (DSM with the mutual information communication between the distributor operation company and the smart devices in real-time. Controllable load management not only has the advantage of peak shaving, load balance, frequency regulation, and voltage stability, but is also effective at providing fast balancing services to the renewable energy grid in the distributed power system. The load management faces an enormous challenge as the customer has a large number of both small residential loads and dispersed renewable sources. In this paper, various controllable load management approaches are discussed. The traditional controllable load approaches such as the end users’ controllable appliances, storage battery, Vehicle-to-Grid (V2G, and heat storage are reviewed. The “broad controllable loads” management, such as the microgrid, Virtual Power Plant (VPP, and the load aggregator are also presented. Furthermore, the load characteristics, control strategies, and control effectiveness are analyzed.

  19. Multiple Model Approaches to Modelling and Control,

    DEFF Research Database (Denmark)

    solving. More complex plants, advances in information technology, and tightened economical and environmental constraints in recent years have lead topractising engineers being faced with modelling and control problems of increasing complexity. When confronted with such problems, there is a strongintuitive......Why Multiple Models?This book presents a variety of approaches which produce complex models or controllers by piecing together a number of simpler subsystems. Thisdivide-and-conquer strategy is a long-standing and general way of copingwith complexity in engineering systems, nature and human problem...... appeal in building systems which operate robustly over a wide range of operating conditions by decomposing them into a number of simplerlinear modelling or control problems, even for nonlinear modelling or control problems. This appeal has been a factor in the development of increasinglypopular `local...

  20. Operator approach to linear control systems

    CERN Document Server

    Cheremensky, A

    1996-01-01

    Within the framework of the optimization problem for linear control systems with quadratic performance index (LQP), the operator approach allows the construction of a systems theory including a number of particular infinite-dimensional optimization problems with hardly visible concreteness. This approach yields interesting interpretations of these problems and more effective feedback design methods. This book is unique in its emphasis on developing methods for solving a sufficiently general LQP. Although this is complex material, the theory developed here is built on transparent and relatively simple principles, and readers with less experience in the field of operator theory will find enough material to give them a good overview of the current state of LQP theory and its applications. Audience: Graduate students and researchers in the fields of mathematical systems theory, operator theory, cybernetics, and control systems.

  1. Multimodel Approach for Intelligent Control and Applications

    Institute of Scientific and Technical Information of China (English)

    Abdelkader El Kamel; Pierre Borne

    2004-01-01

    The use of the multimodel approach in the modelling, analysis and control of non-linear complex and/or ill-defined systems was advocated by many researchers. This approach supposes the definition of a set of local models valid in a given region or domain. Different strategies exist in the literature and are generally based on a partitioning of the non-linear system's full range of operation into multiple smaller operating regimes each of which is associated with a locally valid model or controller. However, most of these strategies, which suppose the determination of these local models as well as their validity domain, remain arbitrary and are generally fixed thanks to a certain a priori knowledge of the system whatever its order. Recently, we have proposed a new approach to derive a multimodel basis which allows us to limit the number of models in the basis to almost four models. Meanwhile, the transition problem between the different models, which may use either a simple commutation or a fusion technique, remains still arise. In this plenary talk, a fuzzy fusion technique is presented and has the following main advantages: (1) use of a fuzzy partitioning in order to determine the validity of each model which enhances the robustness of the solution; (2) introduction, besides the four extreme models, of another model, called average model, determined as an average of the boundary models.

  2. Comparison of Routable Control System Security Approaches

    Energy Technology Data Exchange (ETDEWEB)

    Edgar, Thomas W.; Hadley, Mark D.; Carroll, Thomas E.; Manz, David O.; Winn, Jennifer D.

    2011-06-01

    This document is an supplement to the 'Secure and Efficient Routable Control Systems.' It addressed security in routable control system communication. The control system environment that monitors and manages the power grid historically has utilized serial communication mechanisms. Leased-line serial communication environments operating at 1200 to 9600 baud rates are common. However, recent trends show that communication media such as fiber, optical carrier 3 (OC-3) speeds, mesh-based high-speed wireless, and the Internet are becoming the media of choice. In addition, a dichotomy has developed between the electrical transmission and distribution environments, with more modern communication infrastructures deployed by transmission utilities. The preceding diagram represents a typical control system. The Communication Links cloud supports all of the communication mechanisms a utility might deploy between the control center and devices in the field. Current methodologies used for security implementations are primarily led by single vendors or standards bodies. However, these entities tend to focus on individual protocols. The result is an environment that contains a mixture of security solutions that may only address some communication protocols at an increasing operational burden for the utility. A single approach is needed that meets operational requirements, is simple to operate, and provides the necessary level of security for all control system communication. The solution should be application independent (e.g., Distributed Network Protocol/Internet Protocol [DNP/IP], International Electrotechnical Commission [IEC] C37.118, Object Linking and Embedding for Process Control [OPC], etc.) and focus on the transport layer. In an ideal setting, a well-designed suite of standards for control system communication will be used for vendor implementation and compliance testing. An expected outcome of this effort is an international standard.

  3. Approaches to Learning to Control Dynamic Uncertainty

    Directory of Open Access Journals (Sweden)

    Magda Osman

    2015-10-01

    Full Text Available In dynamic environments, when faced with a choice of which learning strategy to adopt, do people choose to mostly explore (maximizing their long term gains or exploit (maximizing their short term gains? More to the point, how does this choice of learning strategy influence one’s later ability to control the environment? In the present study, we explore whether people’s self-reported learning strategies and levels of arousal (i.e., surprise, stress correspond to performance measures of controlling a Highly Uncertain or Moderately Uncertain dynamic environment. Generally, self-reports suggest a preference for exploring the environment to begin with. After which, those in the Highly Uncertain environment generally indicated they exploited more than those in the Moderately Uncertain environment; this difference did not impact on performance on later tests of people’s ability to control the dynamic environment. Levels of arousal were also differentially associated with the uncertainty of the environment. Going beyond behavioral data, our model of dynamic decision-making revealed that, in actual fact, there was no difference in exploitation levels between those in the highly uncertain or moderately uncertain environments, but there were differences based on sensitivity to negative reinforcement. We consider the implications of our findings with respect to learning and strategic approaches to controlling dynamic uncertainty.

  4. Transgenic approaches to western corn rootworm control.

    Science.gov (United States)

    Narva, Kenneth E; Siegfried, Blair D; Storer, Nicholas P

    2013-01-01

    The western corn rootworm, Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae) is a significant corn pest throughout the United States corn belt. Rootworm larvae feed on corn roots causing yield losses and control expenditures that are estimated to exceed US$1 billion annually. Traditional management practices to control rootworms such as chemical insecticides or crop rotation have suffered reduced effectiveness due to the development of physiological and behavioral resistance. Transgenic maize expressing insecticidal proteins are very successful in protecting against rootworm damage and preserving corn yield potential. However, the high rate of grower adoption and early reliance on hybrids expressing a single mode of action and low-dose traits threatens the durability of commercialized transgenic rootworm technology for rootworm control. A summary of current transgenic approaches for rootworm control and the corresponding insect resistance management practices is included. An overview of potential new modes of action based on insecticidal proteins, and especially RNAi targeting mRNA coding for essential insect proteins is provided.

  5. Immunocontraceptives: New Approaches to Fertility Control

    Directory of Open Access Journals (Sweden)

    Kiranjeet Kaur

    2014-01-01

    Full Text Available The rapidly increasing global population has bowed the attention of family planning and associated reproductive health programmes in the direction of providing a safe and reliable method which can be used to limit family size. The world population is estimated to exceed a phenomenal 10 billion by the year 2050 A.D., thus presenting a real jeopardy of overpopulation with severe implications for the future. Despite the availability of contraceptive methods, there are over one million elective abortions globally each year due to unintended pregnancies, having devastating impact on reproductive health of women worldwide. This highlights the need for the development of newer and improved contraceptive methods. A novel contraceptive approach that is gaining substantial attention is “immunocontraception” targeting gamete production, gamete outcome, or gamete function. Amongst these, use of sperm antigens (gamete function seems to be an exciting and feasible approach. However, the variability of immune response and time lag to attain titer among vaccinated individuals after active immunization has highlighted the potential relevance of preformed antibodies in this league. This review is an attempt to analyze the current status and progress of immunocontraceptive approaches with respect to their establishment as a future fertility control agent.

  6. Distributed memory approaches for robotic neural controllers

    Science.gov (United States)

    Jorgensen, Charles C.

    1990-01-01

    The suitability is explored of two varieties of distributed memory neutral networks as trainable controllers for a simulated robotics task. The task requires that two cameras observe an arbitrary target point in space. Coordinates of the target on the camera image planes are passed to a neural controller which must learn to solve the inverse kinematics of a manipulator with one revolute and two prismatic joints. Two new network designs are evaluated. The first, radial basis sparse distributed memory (RBSDM), approximates functional mappings as sums of multivariate gaussians centered around previously learned patterns. The second network types involved variations of Adaptive Vector Quantizers or Self Organizing Maps. In these networks, random N dimensional points are given local connectivities. They are then exposed to training patterns and readjust their locations based on a nearest neighbor rule. Both approaches are tested based on their ability to interpolate manipulator joint coordinates for simulated arm movement while simultaneously performing stereo fusion of the camera data. Comparisons are made with classical k-nearest neighbor pattern recognition techniques.

  7. Radiopharmaceutical quality control-Pragmatic approach

    International Nuclear Information System (INIS)

    The quality control must be considered in a practical manner. The radiopharmaceuticals are drugs. They must satisfy the quality assurance control. These products are then conform to Pharmacopeia. But sometimes the user must control some data especially radiochemical purity and pH value. On all the administered solutions four controls are compulsory: radionuclide identity, administered radioactivity, organoleptic character and pH

  8. Vision Based Fuzzy Control Approaches for Unmanned Aerial Vehicles

    OpenAIRE

    Olivares Mendez, Miguel Angel; Campoy, Pascual

    2015-01-01

    This paper proposed the use of vision based Fuzzy control approaches for autonomous navigation tasks with Unmanned Aerial Vehicles (UAVs). It is shown the advantages of using RGB cameras as the sensor onboard UAVs and the advantages of using Fuzzy logic controllers. It is explained how to set a vision based system and how to define a Fuzzy controller for a general control approach. A specific software was design and used to develop and tune general Fuzzy control app...

  9. Frequency Transmission Control of Local Networked Control Systems Approach

    OpenAIRE

    O. Esquivel-Flores; H. Benítez-Pérez

    2012-01-01

    The use of Network Control Systems has been successful in the industry and therefore has opened several lines ofresearch. Control systems over a communication network include two important considerations, control andscheduling. Co-design strategies are focused on maintaining adequate control performance and maximize the level ofservice. Network scheduling is the main objective to resolve because through a balanced data load is possible tomaintain control performance in a desired level. This a...

  10. Access control, security, and trust a logical approach

    CERN Document Server

    Chin, Shiu-Kai

    2010-01-01

    Access Control, Security, Trust, and Logic Deconstructing Access Control Decisions A Logical Approach to Access Control PRELIMINARIES A Language for Access ControlSets and Relations Syntax SemanticsReasoning about Access Control Logical RulesFormal Proofs and Theorems Soundness of Logical RulesBasic Concepts Reference Monitors Access Control Mechanisms: Tickets and Lists Authentication Security PoliciesConfidentiality, Integrity, and Availability Discretionary Security Policies Mandatory Security Policies Military Security Policies Commercial PoliciesDISTRIBUTED ACCESS CONTROL Digital Authenti

  11. A Biclustering Approach to Combinatorial Transcription Control

    OpenAIRE

    Srinivasan, Venkataraghavan

    2005-01-01

    Combinatorial control of transcription is a well established phenomenon in the cell. Multiple transcription factors often bind to the same transcriptional control region of a gene and interact with each other to control the expression of the gene. It is thus necessary to consider the joint conservation of sequence pairs in order to identify combinations of binding sites to which the transcription factors bind. Conventional motif finding algorithms fail to address this issue. We propose a nove...

  12. Configurations of Control: A Transaction Cost Approach

    NARCIS (Netherlands)

    R.F. Speklé (Roland)

    2003-01-01

    textabstractIn this paper, I present a theory of management control based on Transaction Cost Economics. This theory seeks to integrate into a single framework a set of insights as to the nature of the organization's activities, the control problems that are inherent in these activities, and the uni

  13. A hybrid approach to space power control

    Science.gov (United States)

    Gholdston, E. W.; Janik, D. F.; Newton, K. A.

    1990-01-01

    Conventional control systems have traditionally been utilized for space-based power designs. However, the use of expert systems is becoming important for NASA applications. Rocketdyne has been pursuing the development of expert systems to aid and enhance control designs of space-based power systems. The need for integrated expert systems is vital for the development of autonomous power systems.

  14. Adaptive Control with Approximated Policy Search Approach

    Directory of Open Access Journals (Sweden)

    Agus Naba

    2010-05-01

    Full Text Available Most of existing adaptive control schemes are designed to minimize error between plant state and goal state despite the fact that executing actions that are predicted to result in smaller errors only can mislead to non-goal states. We develop an adaptive control scheme that involves manipulating a controller of a general type to improve its performance as measured by an evaluation function. The developed method is closely related to a theory of Reinforcement Learning (RL but imposes a practical assumption made for faster learning. We assume that a value function of RL can be approximated by a function of Euclidean distance from a goal state and an action executed at the state. And, we propose to use it for the gradient search as an evaluation function. Simulation results provided through application of the proposed scheme to a pole-balancing problem using a linear state feedback controller and fuzzy controller verify the scheme’s efficacy.

  15. Frequency Transmission Control of Local Networked Control Systems Approach

    Directory of Open Access Journals (Sweden)

    O. Esquivel-Flores

    2012-08-01

    Full Text Available The use of Network Control Systems has been successful in the industry and therefore has opened several lines ofresearch. Control systems over a communication network include two important considerations, control andscheduling. Co-design strategies are focused on maintaining adequate control performance and maximize the level ofservice. Network scheduling is the main objective to resolve because through a balanced data load is possible tomaintain control performance in a desired level. This article reviews a scheduling strategy based on frequencytransition modeled as a linear subsystem, this control reconfigure on line the sensors’ periods. The case of study isthe control of a prototype helicopter and by numerical simulations it shows the effect of changing the transmissionfrequency.

  16. Distributed Stochastic Control: A Team Theoretic Approach

    OpenAIRE

    Gattami, Ather

    2006-01-01

    We consider the problem of stochastic control under constraints on the information structure. We review some old results from static team theory, where new simple proofs are given. The signaling phenomenon in distributed optimal linear quadratic Gaussian control plays a central role because of the NP-hardness it implicates. Necessary and sufficient conditions for eliminating the signaling incentive are given in terms of the interconnection structure.

  17. Parametric Approach to Trajectory Tracking Control of Robot Manipulators

    OpenAIRE

    Shijie Zhang; Yi Ning

    2013-01-01

    The mathematic description of the trajectory of robot manipulators with the optimal trajectory tracking problem is formulated as an optimal control problem, and a parametric approach is proposed for the optimal trajectory tracking control problem. The optimal control problem is first solved as an open loop optimal control problem by using a time scaling transform and the control parameterization method. Then, by virtue of the relationship between the optimal open loop control and the optimal ...

  18. Intelligent Approaches to Real Time Level Control

    Directory of Open Access Journals (Sweden)

    Snejana Yordanova

    2015-09-01

    Full Text Available Liquid level control is important for ensuring energy and material balance in many installations but it also difficult as the plant is nonlinear, inertial and with model uncertainties. Fuzzy logic controllers (FLCs are successfully applied to ensure system stability and robustness by simple means and a model-free design. This paper suggests a procedure for off-line tuning of the many FLC parameters based on optimization of a suggested multi-objective function defined on several system performance indices using genetic algorithms (GAs. First, a model-free FLC is empirically tuned, then applied for real time control of the plant and the necessary data recorded and used to GA parameter optimize a TSK plant model of an accepted structure. The validated on different set of experimental data model is employed in FLC closed loop system simulation experiments to evaluate the fitness function in the GA optimization of the FLC pre-processing and post-processing parameters. The procedure is applied for the real time PI/PID FLC level control in a laboratory-scale tank system. The improvement of the system performance indices due to the GA optimization is estimated in level real time control.

  19. Optical pulse shaping approaches to coherent control

    International Nuclear Information System (INIS)

    The last part of the twentieth century has experienced a huge resurge of activity in the field of coherent light-matter interaction, more so in attempting to exert control over such interactions. Birth of coherent control was originally spurred by the theoretical understanding of the quantum interferences that lead to energy randomization and experimental developments in ultrafast laser spectroscopy. The theoretical predictions on control of reaction channels or energy randomization processes are still more dramatic than the experimental demonstrations, though this gap between the two is consistently reducing over the recent years with realistic theoretical models and technological developments. Experimental demonstrations of arbitrary optical pulse shaping have made some of the previously impracticable theoretical predictions possible to implement. Starting with the simple laser modulation schemes to provide proof-of-the-principle demonstrations, feedback loop pulse shaping systems have been developed that can actively manipulate some atomic and molecular processes. This tremendous experimental boost of optical pulse shaping developments has prospects and implications into many more new directions, such as quantum computing and terabit/sec data communications. This review captures certain aspects and impacts of optical pulse shaping into the fast developing areas of coherent control and other related fields. Currently available reviews focus on one or the other detailed aspects of coherent control, and the reader will be referred to such details as and when necessary for issues that are dealt in brief here. We will focus on the current issues including control of intramolecular dynamics and make connections to the future concepts, such as, quantum computation, biomedical applications, etc

  20. Statistical quality control a loss minimization approach

    CERN Document Server

    Trietsch, Dan

    1999-01-01

    While many books on quality espouse the Taguchi loss function, they do not examine its impact on statistical quality control (SQC). But using the Taguchi loss function sheds new light on questions relating to SQC and calls for some changes. This book covers SQC in a way that conforms with the need to minimize loss. Subjects often not covered elsewhere include: (i) measurements, (ii) determining how many points to sample to obtain reliable control charts (for which purpose a new graphic tool, diffidence charts, is introduced), (iii) the connection between process capability and tolerances, (iv)

  1. A lexicographic approach to constrained MDP admission control

    Science.gov (United States)

    Panfili, Martina; Pietrabissa, Antonio; Oddi, Guido; Suraci, Vincenzo

    2016-02-01

    This paper proposes a reinforcement learning-based lexicographic approach to the call admission control problem in communication networks. The admission control problem is modelled as a multi-constrained Markov decision process. To overcome the problems of the standard approaches to the solution of constrained Markov decision processes, based on the linear programming formulation or on a Lagrangian approach, a multi-constraint lexicographic approach is defined, and an online implementation based on reinforcement learning techniques is proposed. Simulations validate the proposed approach.

  2. A New Approach to Robust and Fault Tolerant Control

    Institute of Scientific and Technical Information of China (English)

    Kemin Zhou

    2005-01-01

    In this paper, we shall summarize a new approach to robust and fault tolerant control proposed recently by the author. This approach is based on a variation of all controller parametrization. This robust and fault-tolerant control design consists of two parts: a nominal performance controller and a robustness controller, and works in such a way that when a component (sensor,actuator, etc.) failure is detected, the controller structure is reconfigured by adding a robustness loop to compensate the fault. We shall illustrate how this strategy works under various situations.

  3. Computer science approach to quantum control

    OpenAIRE

    Janzing, Dominik

    2006-01-01

    This work considers several hypothetical control processes on the nanoscopic level and show their analogy to computation processes. It shows that measuring certain types of quantum observables is such a complex task that every instrument that is able to perform it would necessarily be an extremely powerful computer.

  4. Greenhouse climate management: an optimal control approach.

    NARCIS (Netherlands)

    Henten, van E.J.

    1994-01-01

    In this thesis a methodology is developed for the construction and analysis of an optimal greenhouse climate control system.In chapter 1, the results of a literature survey are presented and the research objectives are defined. In the literature, optimal greenhouse climate management systems have be

  5. Intersectoral approaches to dengue vector control.

    Science.gov (United States)

    Kay, B H

    1994-12-01

    Medical entomology in the context of urban vector control, especially for dengue, can be likened to the tail of a dog. Vertically structured Aedes aegypti campaigns such as run by Gorgas and Soper earlier this century relied on sufficient legislative backing for vector control to ensure that the tail was capable of wagging the dog. Under these conditions, especially where individual rights do not intrude, vertical programs will be successful. The global expansion of dengue, dengue hemorrhagic fever and its vectors, plus growing trends towards urban/periurban living indicate a more serious scenario than at present. In 1987, the Brundtland Report: "Our Common Future" decried sectoralism in problem solving. Following the United Nations Conference on Environment and Development (UNCED) in 1992, the resulting Commission on Sustainable Development has promoted the intersectoral message of health, environment and development. The WHO/FAO/UNEP/UNCHS Panel of Experts on Environmental Management for Vector Control has promoted this for some time and is attempting to build multidisciplinary projects against urban vector borne disease. Adequate solid waste management and recycling will reduce numbers of water bearing containers infested with Aedes aegypti and provision of reliable piped water supplies will impact heavily on infested water storage containers. Both should be encouraged as viable control options. For much of the world, vertical programs have been reported as prohibitively expensive, and unacceptable intrusion on human rights and thus unsustainable in the modern economic context. However there are successful modern examples.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7844851

  6. Computer science approach to quantum control

    Energy Technology Data Exchange (ETDEWEB)

    Janzing, D.

    2006-07-01

    Whereas it is obvious that every computation process is a physical process it has hardly been recognized that many complex physical processes bear similarities to computation processes. This is in particular true for the control of physical systems on the nanoscopic level: usually the system can only be accessed via a rather limited set of elementary control operations and for many purposes only a concatenation of a large number of these basic operations will implement the desired process. This concatenation is in many cases quite similar to building complex programs from elementary steps and principles for designing algorithm may thus be a paradigm for designing control processes. For instance, one can decrease the temperature of one part of a molecule by transferring its heat to the remaining part where it is then dissipated to the environment. But the implementation of such a process involves a complex sequence of electromagnetic pulses. This work considers several hypothetical control processes on the nanoscopic level and show their analogy to computation processes. We show that measuring certain types of quantum observables is such a complex task that every instrument that is able to perform it would necessarily be an extremely powerful computer. Likewise, the implementation of a heat engine on the nanoscale requires to process the heat in a way that is similar to information processing and it can be shown that heat engines with maximal efficiency would be powerful computers, too. In the same way as problems in computer science can be classified by complexity classes we can also classify control problems according to their complexity. Moreover, we directly relate these complexity classes for control problems to the classes in computer science. Unifying notions of complexity in computer science and physics has therefore two aspects: on the one hand, computer science methods help to analyze the complexity of physical processes. On the other hand, reasonable

  7. A Guerilla Approach to Control System Development

    OpenAIRE

    Dovc, J.; Milcinski, G; Plesko, M.

    2001-01-01

    We present our experiences in managing the development cycles of the control systems for ANKA and the ALMA Common Software. Our team consists practically only of undergraduate students. Stimulating and rewarding the students with cutting-edge technologies and travel to conferences like this and installation fieldwork are an important positive factor in raising their motivation. However, building any system with a group of inexperienced students is quite a challenging task. Many problems occur...

  8. Wind Turbine Control: Robust Model Based Approach

    DEFF Research Database (Denmark)

    Mirzaei, Mahmood

    In the 1970s the oil price crisis encouraged investigation of non-petroleum energy sources of which wind energy was the most promising one. Lately global warming concerns have even intensified the demand for green and sustainable energy resources and opened up several lines of research in this area...... papers that are published or going to be published. Control methods which were briefly introduced in chapter 3 are explained in these chapters in details....

  9. Artificial intelligence approach to accelerator control systems

    International Nuclear Information System (INIS)

    An experiment was recently started at LAMPF to evaluate the power and limitations of using artificial intelligence techniques to solve problems in accelerator control and operation. A knowledge base was developed to describe the characteristics and the relationships of the first 30 devices in the LAMPF H+ beam line. Each device was categorized and pertinent attributes for each category defined. Specific values were assigned in the knowledge base to represent each actual device. Relationships between devices are modeled using the artificial intelligence techniques of rules, active values, and object-oriented methods. This symbolic model, built using the Knowledge Engineering Environment (KEE) system, provides a framework for analyzing faults, tutoring trainee operators, and offering suggestions to assist in beam tuning. Based on information provided by the domain expert responsible for tuning this portion of the beam line, additional rules were written to describe how he tunes, how he analyzes what is actually happening, and how he deals with failures. Initial results have shown that artificial intelligence techniques can be a useful adjunct to traditional methods of numerical simulation. Successful and efficient operation of future accelerators may depend on the proper merging of symbolic reasoning and conventional numerical control algorithms

  10. Inventory control in supply chains an internal model control approach /

    OpenAIRE

    García Salcedo, Carlos Andrés

    2013-01-01

    Esta tesis se basa en el diseño de estrategias de gestión de inventario en cadenas de suministro usando la teoría de control. El principal objetivo es proponer un esquema de control para resolver los principales problemas que aparecen en el controla gestión de inventario de una cadena de suministro (incertidumbre en el retardo, el efecto látigo y el déficit de inventario). Este objetivo principal se divide en dos objetivos: 1. La neutralización de los efectos causados por el retardo de e...

  11. A stochastic approach to robust broadband structural control

    Science.gov (United States)

    Macmartin, Douglas G.; Hall, Steven R.

    1992-01-01

    Viewgraphs on a stochastic approach to robust broadband structural control are presented. Topics covered include: travelling wave model; dereverberated mobility model; computation of dereverberated mobility; power flow; impedance matching; stochastic systems; control problem; control of stochastic systems; using cost functional; Bernoulli-Euler beam example; compensator design; 'power' dual variables; dereverberation of complex structure; and dereverberated transfer function.

  12. An integrated approach to modeling and adaptive control

    Institute of Scientific and Technical Information of China (English)

    HAN Zhi-gang

    2006-01-01

    In the book (Adaptive Identification,Prediction and Control-Multi Level Recursive Approach), the concept of dynamical linearization of nonlinear systems has been presented.This dynamical linearization is formal only,not a real linearization.From the linearization procedure,we can find a new approach of system identification,which is on-line real-time modeling and real-time feedback control correction.The modeling and real-time feedback control have been integrated in the identification approach,with the parameter adaptation model being abandoned.The structure adaptation of control systems has been achieved,which avoids the complex modeling steps.The objective of this paper is to introduce the approach of integrated modeling and control.

  13. A Guerilla Approach to Control System Development

    CERN Document Server

    Dovc, J; Plesko, M

    2001-01-01

    We present our experiences in managing the development cycles of the control systems for ANKA and the ALMA Common Software. Our team consists practically only of undergraduate students. Stimulating and rewarding the students with cutting-edge technologies and travel to conferences like this and installation fieldwork are an important positive factor in raising their motivation. However, building any system with a group of inexperienced students is quite a challenging task. Many problems occur with planning deadlines and missing them, organizing and managing development, sources, and documentation and also when dealing with conventional program management rules. To cope with them, we use many tools: CVS for versioning and source archiving, Bugzilla for keeping our bugs in order, a to-do list for managing tasks, an activity log and also many other programs and scripts, some found on the Internet and some made by ourselves. In the end, we had to become organized like a professional company. Documentation and dem...

  14. Mechanical systems a unified approach to vibrations and controls

    CERN Document Server

    Gans, Roger F

    2015-01-01

    This essential textbook covers analysis and control of engineering mechanisms, which include almost any apparatus with moving parts used in daily life, from musical instruments to robots. The text  presents both vibrations and controls with considerable breadth and depth using a unified notation. It strikes a nice balance between the analytical and the practical.  This text contains enough material for a two semester sequence, but it can also be used in a single semester course combining the two topics. Mechanical Systems: A Unified Approach to Vibrations and Controls presents a common notation and approach to these closely related areas. Examples from the both vibrations and controls components are integrated throughout this text. This book also: ·         Presents a unified approach to vibrations and controls, including an excellent diagram that simultaneously discusses embedding classical vibrations (mechanical systems) in a discussion of models, inverse models, and open and closed loop control ...

  15. The control-of-consumption approach to alcohol abuse prevention

    DEFF Research Database (Denmark)

    Ravn, Ib

    1987-01-01

    The single-distribution theory of alcohol consumption and the derived prevention strategy, the control-of-consumption approach, are conceptualized as three probabilistic relationships between four variables, collectively called "the Ledermann string": availability, average consumption, proportion...

  16. A theoretical approach on controlling agricultural pest by biological controls.

    Science.gov (United States)

    Mondal, Prasanta Kumar; Jana, Soovoojeet; Kar, T K

    2014-03-01

    In this paper we propose and analyze a prey-predator type dynamical system for pest control where prey population is treated as the pest. We consider two classes for the pest namely susceptible pest and infected pest and the predator population is the natural enemy of the pest. We also consider average delay for both the predation rate i.e. predation to the susceptible pest and infected pest. Considering a subsystem of original system in the absence of infection, we analyze the existence of all possible non-negative equilibria and their stability criteria for both the subsystem as well as the original system. We present the conditions for transcritical bifurcation and Hopf bifurcation in the disease free system. The theoretical evaluations are demonstrated through numerical simulations.

  17. LMI approach to reliable H∞ control of linear systems

    Institute of Scientific and Technical Information of China (English)

    Yao Bo; Wang Fuzhong

    2006-01-01

    The reliable design problem for linear systems is concerned with. A more practical model of actuator faults than outage is considered. An LMI approach of designing reliable controller is presented for the case of actuator faults that can be modeled by a scaling factor. The resulting control systems are reliable in that they provide guaranteed asymptotic stability and H∞ performance when some control component (actuator) faults occur. A numerical example is also given to illustrate the design procedure and their effectiveness. Furthermore, the optimal standard controller and the optimal reliable controller are compared to show the necessity of reliable control.

  18. REDUCTION APPROACHES FOR VIBRATION CONTROL OF REPETITIVE STRUCTURES

    Institute of Scientific and Technical Information of China (English)

    CHEN Wei-min; SUN Dong-chang; WANG Da-jun; WEI Jian-ping; TONG Li-yong; WANG Quan

    2006-01-01

    The reduction approaches are presented for vibration control of symmetric,cyclic periodic and linking structures. The condensation of generalized coordinates, the locations of sensors and actuators, and the relation between system inputs and control forces are assumed to be set in a symmetric way so that the control system posses the same repetition as the structure considered. By employing proper transformations of condensed generalized coordinates and the system inputs, the vibration control of an entire system can be implemented by carrying out the control of a number of sub-structures, and thus the dimension of the control problem can be significantly reduced.

  19. A "Hybrid" Approach for Synthesizing Optimal Controllers of Hybrid Systems

    DEFF Research Database (Denmark)

    Zhao, Hengjun; Zhan, Naijun; Kapur, Deepak;

    2012-01-01

    We propose an approach to reduce the optimal controller synthesis problem of hybrid systems to quantifier elimination; furthermore, we also show how to combine quantifier elimination with numerical computation in order to make it more scalable but at the same time, keep arising errors due...... to discretization manageable and within bounds. A major advantage of our approach is not only that it avoids errors due to numerical computation, but it also gives a better optimal controller. In order to illustrate our approach, we use the real industrial example of an oil pump provided by the German company HYDAC...

  20. A switched system approach to stabilization f networked control systems

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    A switched system approach is proposed to model networked control systems (NCSs) with communication constraints. This enables us to apply the rich theory of switched systems to analyzing such NCSs. Sufficient conditions are presented on the stabilization of NCSs. Stabilizing state/output feedback controllers can be constructed by using the feasible solutions of some linear matrix inequalities (LMIs). The merit of our proposed approach is that the behavior of the NCSs can be studied by considering switched system without augmenting the system. A simulation example is worked out to illustrate the effectiveness of the proposed approach.

  1. A systems approach to malaria control: an institutional perspective

    NARCIS (Netherlands)

    Temel, T.

    2005-01-01

    This study introduces a systems approach to malaria control. Comprising organizations from the health, environmental, agricultural, economic, political, and social sectors, the malaria control system (MCS) at hand is organized around a common goal of improving living conditions through reduced malar

  2. A control approach for plasma density in tokamak machines

    Energy Technology Data Exchange (ETDEWEB)

    Boncagni, Luca, E-mail: luca.boncagni@enea.it [EURATOM – ENEA Fusion Association, Frascati Research Center, Division of Fusion Physics, Rome, Frascati (Italy); Pucci, Daniele; Piesco, F.; Zarfati, Emanuele [Dipartimento di Ingegneria Informatica, Automatica e Gestionale ' ' Antonio Ruberti' ' , Sapienza Università di Roma (Italy); Mazzitelli, G. [EURATOM – ENEA Fusion Association, Frascati Research Center, Division of Fusion Physics, Rome, Frascati (Italy); Monaco, S. [Dipartimento di Ingegneria Informatica, Automatica e Gestionale ' ' Antonio Ruberti' ' , Sapienza Università di Roma (Italy)

    2013-10-15

    Highlights: •We show a control approach for line plasma density in tokamak. •We show a control approach for pressure in a tokamak chamber. •We show experimental results using one valve. -- Abstract: In tokamak machines, chamber pre-fill is crucial to attain plasma breakdown, while plasma density control is instrumental for several tasks such as machine protection and achievement of desired plasma performances. This paper sets the principles of a new control strategy for attaining both chamber pre-fill and plasma density regulation. Assuming that the actuation mean is a piezoelectric valve driven by a varying voltage, the proposed control laws ensure convergence to reference values of chamber pressure during pre-fill, and of plasma density during plasma discharge. Experimental results at FTU are presented to discuss weaknesses and strengths of the proposed control strategy. The whole system has been implemented by using the MARTe framework [1].

  3. A methodological approach to designing sewer system control

    DEFF Research Database (Denmark)

    Mollerup, Ane Loft

    classical control theory, such as the calculation of the condition number and the relative gain array, could be successfully applied to the sewer system. Based on the results a pairing between the measurements variables and the actuators could be suggested. Having proposed to decompose the sewer system...... constant setpoints. However, in a transient system like the sewer system, the setpoints may change dramatically and rapidly. Therefore the regulatory control layer may not have the same functionality when designed for the sewer system. From the application of the classical control theory it was found...... for this thesis was therefore the wish for a methodological approach to sewer system control design. Using a case study the following research hypothesis was tested in this thesis: Using classical and modern control theory, a methodological approach can be derived for designing sewer system control. This can aid...

  4. A Riccati approach for constrained linear quadratic optimal control

    Science.gov (United States)

    Sideris, Athanasios; Rodriguez, Luis A.

    2011-02-01

    An active-set method is proposed for solving linear quadratic optimal control problems subject to general linear inequality path constraints including mixed state-control and state-only constraints. A Riccati-based approach is developed for efficiently solving the equality constrained optimal control subproblems generated during the procedure. The solution of each subproblem requires computations that scale linearly with the horizon length. The algorithm is illustrated with numerical examples.

  5. Martingale Approach to Stochastic Control with Discretionary Stopping

    International Nuclear Information System (INIS)

    We develop a martingale approach for continuous-time stochastic control with discretionary stopping. The relevant Dynamic Programming Equation and Maximum Principle are presented. Necessary and sufficient conditions are provided for the optimality of a control strategy; these are analogues of the 'equalization' and 'thriftiness' conditions introduced by Dubins and Savage (1976) in a related, discrete-time context. The existence of a thrifty control strategy is established

  6. Active control of smart structures : an overall approach

    OpenAIRE

    Nestorović Tamara; Trajkov Miroslav

    2010-01-01

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

  7. Nonlinear identification and control a neural network approach

    CERN Document Server

    Liu, G P

    2001-01-01

    The series Advances in Industrial Control aims to report and encourage technology transfer in control engineering. The rapid development of control technology has an impact on all areas of the control discipline. New theory, new controllers, actuators, sensors, new industrial processes, computer methods, new applications, new philosophies . . . , new challenges. Much of this development work resides in industrial reports, feasibility study papers and the reports of advanced collaborative projects. The series otTers an opportunity for researchers to present an extended exposition of such new work in all aspects of industrial control for wider and rapid dissemination. The time for nonlinear control to enter routine application seems to be approaching. Nonlinear control has had a long gestation period but much ofthe past has been concerned with methods that involve formal nonlinear functional model representations. It seems more likely that the breakthough will come through the use of other more flexible and ame...

  8. Parametric Approach to Trajectory Tracking Control of Robot Manipulators

    Directory of Open Access Journals (Sweden)

    Shijie Zhang

    2013-01-01

    Full Text Available The mathematic description of the trajectory of robot manipulators with the optimal trajectory tracking problem is formulated as an optimal control problem, and a parametric approach is proposed for the optimal trajectory tracking control problem. The optimal control problem is first solved as an open loop optimal control problem by using a time scaling transform and the control parameterization method. Then, by virtue of the relationship between the optimal open loop control and the optimal closed loop control along the optimal trajectory, a practical method is presented to calculate an approximate optimal feedback gain matrix, without having to solve an optimal control problem involving the complex Riccati-like matrix differential equation coupled with the original system dynamics. Simulation results of 2-link robot manipulator are presented to show the effectiveness of the proposed method.

  9. A variable structure approach to robust control of VTOL aircraft

    Science.gov (United States)

    Calise, A. J.; Kramer, F. S.

    1984-01-01

    This paper examines the application of variable structure control theory to the design of a flight control system for the AV-8A Harrier in a hover mode. The objective in variable structure design is to confine the state trajectories to a subspace of the total state space. The motion in this subspace is insensitive to system parameter variations and external disturbances that lie in the range space of the control. A switching type of control law results from the design procedure. The control system was designed to track a vector-valued velocity command. For comparison, a proportional controller was designed using optimal linear regulator theory. Both controllers were evaluated for their transient response performance using a linear model; then a nonlinear simulation study of a hovering approach to landing was conducted. The variable structure controller outperformed its linear counterpart in the presence of wind disturbances and plant parameter uncertainties afforded by the simulation.

  10. Stochastic Control of Energy Efficient Buildings: A Semidefinite Programming Approach

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Xiao [ORNL; Dong, Jin [ORNL; Djouadi, Seddik M [ORNL; Nutaro, James J [ORNL; Kuruganti, Teja [ORNL

    2015-01-01

    The key goal in energy efficient buildings is to reduce energy consumption of Heating, Ventilation, and Air- Conditioning (HVAC) systems while maintaining a comfortable temperature and humidity in the building. This paper proposes a novel stochastic control approach for achieving joint performance and power control of HVAC. We employ a constrained Stochastic Linear Quadratic Control (cSLQC) by minimizing a quadratic cost function with a disturbance assumed to be Gaussian. The problem is formulated to minimize the expected cost subject to a linear constraint and a probabilistic constraint. By using cSLQC, the problem is reduced to a semidefinite optimization problem, where the optimal control can be computed efficiently by Semidefinite programming (SDP). Simulation results are provided to demonstrate the effectiveness and power efficiency by utilizing the proposed control approach.

  11. Control packages: an approach to solution of positional control problems with incomplete information

    International Nuclear Information System (INIS)

    An approach is proposed for solving problems of positional control of a dynamical system under conditions of incomplete information about its current phase states. The basis of this approach is a new notion of control packages, namely, procedures for constructing control programs which are non-anticipatory with respect to the dynamics of observations. For definiteness, the approach is realised for a concrete control problem of guaranteed guidance of a controlled system to a given target set at a fixed moment of time. The main result of the paper states that the indicated problem is soluble in the class of positional strategies if and only if it is soluble in the class of control packages. This result shows a way to reduce control problems in the positional (closed-loop) formulation to control problems in the program (open-loop) formulation. In this sense a methodology for program constructions is developed that is well known in the theory of positional differential games.

  12. An ecosystem approach to malaria control in an urban setting

    Directory of Open Access Journals (Sweden)

    Carrasquilla Gabriel

    2001-01-01

    Full Text Available We conducted a research project aimed at strengthening local government and the community for a sustainable malaria control strategy. The project began with a baseline diagnosis of malaria prevalence, a KAP survey, entomology, and health services delivery, after which an epidemiological study was performed to identify risk factors associated with malaria, thereafter used to plan intervention measures. A program evaluation was conducted five years later. By using an ecosystem approach to reanalyze data, this paper discusses how malaria arises from a complex interaction of cultural, economic, ecological, social, and individual factors. Intervention measures require an intersectorial and transdisciplinary approach that does not exist at the moment. Health sector leadership is limited, and there is no true community participation. Implications for research, including the use of qualitative and quantitative methods, study design, and complexity of data analysis are discussed. Finally, implications for malaria control are discussed, stressing the differences between the ecosystem and integrated disease control approaches.

  13. An Approach to Robust Control of the Hopf Bifurcation

    Directory of Open Access Journals (Sweden)

    Giacomo Innocenti

    2011-01-01

    Full Text Available The paper illustrates a novel approach to modify the Hopf bifurcation nature via a nonlinear state feedback control, which leaves the equilibrium properties unchanged. This result is achieved by recurring to linear and nonlinear transformations, which lead the system to locally assume the ordinary differential equation representation. Third-order models are considered, since they can be seen as proper representatives of a larger class of systems. The explicit relationship between the control input and the Hopf bifurcation nature is obtained via a frequency approach, that does not need the computation of the center manifold.

  14. The control-of-consumption approach to alcohol abuse prevention

    DEFF Research Database (Denmark)

    Ravn, Ib

    1987-01-01

    Key empirical studies of the postulates of the single-distribution theory and the associated control-of-consumption approach are reviewed. The review is organized in terms of the six links possible between the four variables of the "Ledermann string" (availability, average consumption, proportion...... of heavy consumers, and prevalence of damage) presented in Part I. It is concluded that, on the whole, the available evidence is too inconsistent to support the control-of-consumption approach and that a more comprehensive understanding of alcohol abuse and prevention is needed....

  15. Optimization of nonlinear controller with an enhanced biogeography approach

    Directory of Open Access Journals (Sweden)

    Mohammed Salem

    2014-07-01

    Full Text Available This paper is dedicated to the optimization of nonlinear controllers basing of an enhanced Biogeography Based Optimization (BBO approach. Indeed, The BBO is combined to a predator and prey model where several predators are used with introduction of a modified migration operator to increase the diversification along the optimization process so as to avoid local optima and reach the optimal solution quickly. The proposed approach is used in tuning the gains of PID controller for nonlinear systems. Simulations are carried out over a Mass spring damper and an inverted pendulum and has given remarkable results when compared to genetic algorithm and BBO.

  16. A New Approach for Controlling Chaos Based on Direct Optimizing Predictive Control

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    We introduce the predictive control theory into the study of chaos control and propose a direct optimizing predictive control algorithm based on a neural network model. The proposed control system stabilizes the chaotic motion in an unknown chaotic system onto the desired target trajectory. Compared with the existing similar algorithms, the proposed control system has faster response, so it requires much shorter time for the stabilization of the chaotic systems.The proposed approach can control hyperchaos and the algorithm is simple. The convergence of the control algorithm and the stability of the control system can be guaranteed. The theoretic analysis and simulations demonstrate the effectiveness of the algorithm.

  17. A NEW ADMISSION CONTROL APPROACH BASED ON PREDICTION

    Institute of Scientific and Technical Information of China (English)

    Lu Kaining; Jin Zhigang; Zou Jun

    2002-01-01

    Admission control plays an important role in providing QoS to network users. Motivated by the measurement-based admission control algorithm, this letter proposed a new admission control approach for integrated service packet network based on traffic prediction. In the letter, FARIMA(p, d, q) models in the admission control algorithm is deployed. A method to simplify the FARIMA model fitting procedure and hence to reduce the time of traffic modeling and prediction is suggested. The feasibility-study experiments show that FARIMA models which have less number of parameters can be used to model and predict actual traffic on quite a large time scale. Simulation results validate the promising approach.

  18. 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.

  19. Viability of Hybrid Systems A Controllability Operator Approach

    CERN Document Server

    Labinaz, G

    2012-01-01

    The problem of viability of hybrid systems is considered in this work. A model for a hybrid system is developed including a means of including three forms of uncertainty: transition dynamics, structural uncertainty, and parametric uncertainty. A computational basis for viability of hybrid systems is developed and applied to three control law classes. An approach is developed for robust viability based on two extensions of the controllability operator. The three-tank example is examined for both the viability problem and robust viability problem. The theory is applied through simulation to an active magnetic bearing system and to a batch polymerization process showing that viability can be satisfied in practice. The problem of viable attainability is examined based on the controllability operator approach introduced by Nerode and colleagues. Lastly, properties of the controllability operator are presented.

  20. Adaptive Control of the Chaotic System via Singular System Approach

    Directory of Open Access Journals (Sweden)

    Yudong Li

    2014-01-01

    Full Text Available This paper deals with the control problem of the chaotic system subject to disturbance. The sliding mode surface is designed by singular system approach, and sufficient condition for convergence is given. Then, the adaptive sliding mode controller is designed to make the state arrive at the sliding mode surface in finite time. Finally, Lorenz system is considered as an example to show the effectiveness of the proposed method.

  1. Control approach development for variable recruitment artificial muscles

    Science.gov (United States)

    Jenkins, Tyler E.; Chapman, Edward M.; Bryant, Matthew

    2016-04-01

    This study characterizes hybrid control approaches for the variable recruitment of fluidic artificial muscles with double acting (antagonistic) actuation. Fluidic artificial muscle actuators have been explored by researchers due to their natural compliance, high force-to-weight ratio, and low cost of fabrication. Previous studies have attempted to improve system efficiency of the actuators through variable recruitment, i.e. using discrete changes in the number of active actuators. While current variable recruitment research utilizes manual valve switching, this paper details the current development of an online variable recruitment control scheme. By continuously controlling applied pressure and discretely controlling the number of active actuators, operation in the lowest possible recruitment state is ensured and working fluid consumption is minimized. Results provide insight into switching control scheme effects on working fluids, fabrication material choices, actuator modeling, and controller development decisions.

  2. Singular perturbation approach for control of hydraulically driven flexible manipulator

    Institute of Scientific and Technical Information of China (English)

    LI Guang; WU Min

    2005-01-01

    The hydraulic flexible manipulator system is divided into two parts: flexible arm dynamics and hydraulic servomechanism, a driving Jacobian is derived to connect these two parts. Taking hydraulic actuator force as virtual input, a singular perturbed composite model is formulated and used to design composite controllers for the flexible link, in which the slow subsystem controller dominates the trajectory tracking, and then a fast controller is designed to damp out the vibration of the flexible structure. Moreover, the backstepping technique is applied to regulate the spool position of a hydraulic valve to provide the required force. Simulation results are provided to show the effectiveness of the presented approach.

  3. A novel testing approach for SSRF digital power supply controllers

    Institute of Scientific and Technical Information of China (English)

    KE Xinhua; LU Songlin; LI Rui; XU Ruinian; SHEN Tianjian

    2008-01-01

    Digital power supply controller is one of the key parts of SSRF high resolution high stability magnet power supply system.It is very essential to keep any degradation of these excellent properties by any stages as small as possible via careful testing when the controller is developed.In this study,a novel testing approach was presented,with which a novel closed conrail loop without actual power converter was constructed,and the new developed SSRF Digital Controller can work well in it.

  4. An optimal control approach to probabilistic Boolean networks

    Science.gov (United States)

    Liu, Qiuli

    2012-12-01

    External control of some genes in a genetic regulatory network is useful for avoiding undesirable states associated with some diseases. For this purpose, a number of stochastic optimal control approaches have been proposed. Probabilistic Boolean networks (PBNs) as powerful tools for modeling gene regulatory systems have attracted considerable attention in systems biology. In this paper, we deal with a problem of optimal intervention in a PBN with the help of the theory of discrete time Markov decision process. Specifically, we first formulate a control model for a PBN as a first passage model for discrete time Markov decision processes and then find, using a value iteration algorithm, optimal effective treatments with the minimal expected first passage time over the space of all possible treatments. In order to demonstrate the feasibility of our approach, an example is also displayed.

  5. On the Ecological Approach to Information and Control for Roboticists

    Directory of Open Access Journals (Sweden)

    Jorge Ibáñez-Gijón

    2013-06-01

    Full Text Available The ongoing and increasingly important trend in robotics to conceive designs that decentralize control is paralleled by currently active research paradigms in the study of perception and action. James Gibson’s ecological approach is one of these paradigms. Gibson’s approach emerged in part as a reaction to representationalist and computationalist approaches, which devote the bulk of their resources to the study of internal processes. The ecological approach instead focuses on constraints and ambient energy patterns in the animal‐environment coalition. The present article reviews how the emphasis on the environment by ecological psychologists has given rise to the concepts of direct perception, higher order information, active information pick up, information‐ based control laws, prospective control, and direct learning. Examples are included to illustrate these concepts and to show how they can be applied to the construction of robots. Action is described as emergent and self‐organized. It is argued that knowledge about perception, action, and learning as it occurs in living organisms may facilitate the construction of robots, more obviously so if the aim is to construct (to some extent biologically plausible robots.

  6. Sliding Mode Control Approach for Electrically Controllable Clutch of AMT Based on the Feedback Linearization

    Institute of Scientific and Technical Information of China (English)

    程东升; 张建武; 叶晓峰; 黄维纲

    2003-01-01

    A sliding mode control approach based on the feedback linearization is proposed for the electrically controllable clutch of AMT vehicles. The nonlinear dynamic model for the hydraulic actuator associated with clutch is established. By means of the exact feedback linearization procedure of differential geometry, an equivalent, fully controllable and linear model is derived via a homomorphic transformation for the AMT clutch system.Furthermore, a sliding mode control is introduced to improve robustness. The tracking tests are performed using the sliding mode control on a Santana LX passenger car, and the experimental results prove that this nonlinear controller is of fine robustness and high degree of tracking accuracy.

  7. Distributed Secondary Control for Islanded MicroGrids – A Networked Control Systems Approach

    DEFF Research Database (Denmark)

    Shafiee, Qobad; Vasquez, Juan Carlos; Guerrero, Josep M.

    2012-01-01

    not relies on a central control, so that the failure of a single unit will not produce the fail down of the whole system. Experimental results are presented to show the feasibility of the distributed control. The time latency limits of the communication systems are studied as well....... control system is used in order to implement a distributed secondary control thus avoiding the use of a MicroGrid Central Control. The proposed approach is not only able to restore frequency and voltage of the MicroGrid but also ensures reactive power sharing. The distributed secondary control do...

  8. ADVANZ - Neglected zoonotc disease control through a One Health approach

    DEFF Research Database (Denmark)

    Saarnak, Christopher; Johansen, Maria Vang; Mukaratirwa, Samson

    2013-01-01

    conditions such as hygiene and biosecurity can have an important effect on reducing the risks of transmission. In addition some of the endemic zoonotic diseases can be controlled by interventions such as mass vaccination (e.g rabies), treatment (echinococcosis) and/or creating a simple but effective change...... and marginalized populations. Although the One Health approach initially concentrated on addressing emerging zoonotic diseases and especially pandemic threats, the One Health approach is gaining recognition for addressing endemic/neglected zoonotic diseases as they arise from infections transmitted from...

  9. Controlling Particle Morphologies at Fluid Interfaces: Macro- and Micro- approaches

    Science.gov (United States)

    Beesabathuni, Shilpa Naidu

    The controlled generation of varying shaped particles is important for many applications: consumer goods, biomedical diagnostics, food processing, adsorbents and pharmaceuticals which can benefit from the availability of geometrically complex and chemically inhomogeneous particles. This thesis presents two approaches to spherical and non-spherical particle synthesis using macro and microfluidics. In the first approach, a droplet microfluidic technique is explored to fabricate spherical conducting polymer, polyaniline, particles with precise control over morphology and functionality. Microfluidics has recently emerged as an important alternate to the synthesis of complex particles. The conducting polymer, polyaniline, is widely used and known for its stability, high conductivity, and favorable redox properties. In this approach, monodisperse micron-sized polyaniline spherical particles were synthesized using two-phase droplet microfluidics from Aniline and Ammonium persulfate oxidative polymerization in an oil-based continuous phase. The morphology of the polymerized particles is porous in nature which can be used for encapsulation as well as controlled release applications. Encapsulation of an enzyme, glucose oxidase, was also performed using the technique to synthesize microspheres for glucose sensing. The polymer microspheres were characterized using SEM, UV-Vis and EDX to understand the relationship between their microstructure and stability. In the second approach, molten drop impact in a cooling aqueous medium to generate non-spherical particles was explored. Viscoelastic wax based materials are widely used in many applications and their performance and application depends on the particle morphology and size. The deformation of millimeter size molten wax drops as they impacted an immiscible liquid interface was investigated. Spherical molten wax drops impinged on a cooling water bath, then deformed and as a result of solidification were arrested into various

  10. A new approach for vibration control in large space structures

    Science.gov (United States)

    Kumar, K.; Cochran, J. E., Jr.

    1987-01-01

    An approach for augmenting vibration damping characteristics in space structures with large panels is presented. It is based on generation of bending moments rather than forces. The moments are generated using bimetallic strips, suitably mounted at selected stations on both sides of the large panels, under the influence of differential solar heating, giving rise to thermal gradients and stresses. The collocated angular velocity sensors are utilized in conjunction with mini-servos to regulate the control moments by flipping the bimetallic strips. A simple computation of the rate of dissipation of vibrational energy is undertaken to assess the effectiveness of the proposed approach.

  11. A systematic review of current and emergent manipulator control approaches

    Science.gov (United States)

    Ajwad, Syed Ali; Iqbal, Jamshed; Ullah, Muhammad Imran; Mehmood, Adeel

    2015-06-01

    Pressing demands of productivity and accuracy in today's robotic applications have highlighted an urge to replace classical control strategies with their modern control counterparts. This recent trend is further justified by the fact that the robotic manipulators have complex nonlinear dynamic structure with uncertain parameters. Highlighting the authors' research achievements in the domain of manipulator design and control, this paper presents a systematic and comprehensive review of the state-of-the-art control techniques that find enormous potential in controlling manipulators to execute cuttingedge applications. In particular, three kinds of strategies, i.e., intelligent proportional-integral-derivative (PID) scheme, robust control and adaptation based approaches, are reviewed. Future trend in the subject area is commented. Open-source simulators to facilitate controller design are also tabulated. With a comprehensive list of references, it is anticipated that the review will act as a firsthand reference for researchers, engineers and industrialinterns to realize the control laws for multi-degree of freedom (DOF) manipulators.

  12. Multimodel Predictive Control Approach for UAV Formation Flight

    Directory of Open Access Journals (Sweden)

    Chang-jian Ru

    2014-01-01

    Full Text Available Formation flight problem is the most important and interesting problem of multiple UAVs (unmanned aerial vehicles cooperative control. In this paper, a novel approach for UAV formation flight based on multimodel predictive control is designed. Firstly, the state equation of relative motion is obtained and then discretized. By the geometrical method, the characteristic points of state are determined. Afterwards, based on the linearization technique, the standard linear discrete model is obtained at each characteristic state point. Then, weighted model set is proposed using the idea of T-S (Takagi-Sugeno fuzzy control and the predictive control is carried out based on the multimodel method. Finally, to verify the performance of the proposed method, two different simulation scenarios are performed.

  13. Optimal Control of Vertically Transmitted Disease: An Integrated Approach

    Directory of Open Access Journals (Sweden)

    Samit Bhattacharyya

    2010-01-01

    horizontal transmission, administration of the antiviral drug to infected individuals lessens the chance of vertical transmission. Thus the vaccine and antiviral drug play different roles in controlling the disease, which has both vertical and horizontal transmission. We develop a 3D model with Susceptible–Infected–Recovered under vaccination to the susceptible and antiviral treatment to the infected and consider a control theoretic approach using the Pontryagin maximum principle to analyse the costeffectiveness of the control process. Our results demonstrate that a mixed intervention strategy of vaccination and antiviral drug in a proper ratio is the most effective way to control the disease. We show that cost-effectiveness of both intervention strategies intimately depends on disease-related parameters, such as force of infection, probability of being infected to offspring from infected mothers, loss of immunity or reinfection and also on cost of treatment.

  14. Biological approaches for control of root pathogens of strawberry.

    Science.gov (United States)

    Martin, F N; Bull, C T

    2002-12-01

    ABSTRACT Soil fumigation with methyl bromide plus chloropicrin is used as a preplant treatment to control a broad range of pathogens in high-value annual crop production systems. In California, fumigation is used on approximately 10,125 ha of strawberry production to control pathogens ranging from Verticillium dahliae to root pruning pathogens such as Pythium, Rhizoctonia, or Cylindrocarpon spp. In addition to pathogen control, fumigation also causes an enhanced growth response of the plant and reduces weed pressure. The development of successful, long-term cost effective biocontrol strategies most likely will require the development of an integrated systems approach that incorporates diverse aspects of the crop production system. Although application of single microbial inoculants may provide some level of control for specific production problems, it will be a challenge to provide the broad spectrum of activity needed in production fields. PMID:18943893

  15. Mathematical models for therapeutic approaches to control HIV disease transmission

    CERN Document Server

    Roy, Priti Kumar

    2015-01-01

    The book discusses different therapeutic approaches based on different mathematical models to control the HIV/AIDS disease transmission. It uses clinical data, collected from different cited sources, to formulate the deterministic as well as stochastic mathematical models of HIV/AIDS. It provides complementary approaches, from deterministic and stochastic points of view, to optimal control strategy with perfect drug adherence and also tries to seek viewpoints of the same issue from different angles with various mathematical models to computer simulations. The book presents essential methods and techniques for students who are interested in designing epidemiological models on HIV/AIDS. It also guides research scientists, working in the periphery of mathematical modeling, and helps them to explore a hypothetical method by examining its consequences in the form of a mathematical modelling and making some scientific predictions. The model equations, mathematical analysis and several numerical simulations that are...

  16. Advanced control room evaluation: General approach and rationale

    Energy Technology Data Exchange (ETDEWEB)

    O' Hara, J.M. (Brookhaven National Lab., Upton, NY (USA)); Wachtel, J. (Nuclear Regulatory Commission, Washington, DC (USA))

    1991-01-01

    Advanced control rooms (ACRs) for future nuclear power plants (NPPs) are being designed utilizing computer-based technologies. The US Nuclear Regulatory Commission reviews the human engineering aspects of such control rooms to ensure that they are designed to good human factors engineering principles and that operator performance and reliability are appropriately supported in order to protect public health and safety. This paper describes the rationale and general approach to the development of a human factors review guideline for ACRs. The factors influencing the guideline development are discussed, including the review environment, the types of advanced technologies being addressed, the human factors issues associated with advanced technology, and the current state-of-the-art of human factors guidelines for advanced human-system interfaces (HSIs). The proposed approach to ACR review would track the design and implementation process through the application of review guidelines reflecting four review modules: planning, design process analysis, human factors engineering review, and dynamic performance evaluation. 21 refs.

  17. The consistency approach for the quality control of vaccines.

    Science.gov (United States)

    Hendriksen, Coenraad; Arciniega, Juan L; Bruckner, Lukas; Chevalier, Michel; Coppens, Emmanuelle; Descamps, Johan; Duchêne, Michel; Dusek, David Michael; Halder, Marlies; Kreeftenberg, Hans; Maes, Alexandrine; Redhead, Keith; Ravetkar, Satish D; Spieser, Jean-Marc; Swam, Hanny

    2008-01-01

    Current lot release testing of conventional vaccines emphasizes quality control of the final product and is characterized by its extensive use of laboratory animals. This report, which is based on the outcome of an ECVAM (European Centre for Validation of Alternative Methods, Institute for Health and Consumer Protection, European Commission Joint Research Centre, Ispra, Italy) workshop, discusses the concept of consistency testing as an alternative approach for lot release testing. The consistency approach for the routine release of vaccines is based upon the principle that the quality of vaccines is a consequence of a quality system and of consistent production of lots with similar characteristics to those lots that have been shown to be safe and effective in humans or the target species. The report indicates why and under which circumstances this approach can be applied, the role of the different stakeholders, and the need for international harmonization. It also gives recommendations for its implementation.

  18. Excess Liquidity Control Requires a Multi-Pronged Approach

    Institute of Scientific and Technical Information of China (English)

    李晓西; 和晋予

    2007-01-01

    As China opens wider to the outside world, excess liquidity has become an outstanding issue in economic operations. This paper holds that China’s liquidity is relatively excessive at the present time, and such excess liquidity is a reflection of domestic and foreign economic contradictions on the monetary level. Excess liquidity will pose a potential hazard to macroeconomic operation, and a multi-pronged approach should be taken to curb and control its sources at home and abroad.

  19. Human rights-based approach to tobacco control.

    Science.gov (United States)

    Dresler, Carolyn; Lando, Harry; Schneider, Nick; Sehgal, Hitakshi

    2012-03-01

    The Framework Convention for Tobacco Control (FCTC) is currently the most potent tool for implementation of tobacco control laws across the globe. The FCTC is derivative from previously constructed international human rights conventions. These previous conventions have enforcement mechanisms, unlike the FCTC. However, the FCTC relies on state parties to report periodically on its implementation rather than on a continuous monitoring system. The Human Rights and Tobacco Control Network proposes that abiding by the principles of human rights delineated by international treaties, citizens across the globe can demand effective action for tobacco control. This paper explains the link between fundamental human rights and the right to tobacco control. Mechanisms are described to link the FCTC and its principles with human rights-based monitoring reports, which are provided to oversight committees for the other human rights conventions. The initial work of the Human Rights and Tobacco Control Network is summarised and considers the future directions for the human rights-based approach to tobacco control. PMID:22345248

  20. A new approach to the CZ crystal growth weighing control

    Science.gov (United States)

    Kasimkin, P. V.; Moskovskih, V. A.; Vasiliev, Y. V.; Shlegel, V. N.; Yuferev, V. S.; Vasiliev, M. G.; Zhdankov, V. N.

    2014-03-01

    The aim of a new approach was to improve the robustness of the weighing control of CZ growth especially for semiconductors, for which the “anomalous“ behavior of the apparent weight provokes instability of the servo-loop. In the described method, the periodic reciprocating measuring motion of small amplitude is superposed on the uniform pull-rod movement. The cross-sectional area is determined from the weight sensor responses that are modulated mainly by the forces of hydrostatic pressure. By the example of germanium crystal growth, it is shown that in the control system, based on such a way of the diameter measuring, a simple PI control law provides a good close loop system's stability and dynamics for the materials with the “anomalous” behavior of a weighing signal. The effect of a meniscus on the modulation measuring of a crystal diameter is also discussed.

  1. Stall Recovery Guidance Algorithms Based on Constrained Control Approaches

    Science.gov (United States)

    Stepanyan, Vahram; Krishnakumar, Kalmanje; Kaneshige, John; Acosta, Diana

    2016-01-01

    Aircraft loss-of-control, in particular approach to stall or fully developed stall, is a major factor contributing to aircraft safety risks, which emphasizes the need to develop algorithms that are capable of assisting the pilots to identify the problem and providing guidance to recover the aircraft. In this paper we present several stall recovery guidance algorithms, which are implemented in the background without interfering with flight control system and altering the pilot's actions. They are using input and state constrained control methods to generate guidance signals, which are provided to the pilot in the form of visual cues. It is the pilot's decision to follow these signals. The algorithms are validated in the pilot-in-the loop medium fidelity simulation experiment.

  2. IDCOR approach to hydrogen generation, combustion, and burn control

    International Nuclear Information System (INIS)

    The IDCOR Program is developing the appropriate information and methodology to predict the following phenomena during severe accidents: 1) hydrogen generation, both in-vessel and ex-vessel, primarily from metal-water reactions; 2) hydrogen distribution in reactor containments; and 3) potential hazards of overpressurization or combustion of hydrogen. The information is being assembled into reports describing the phenomenology and incorporated into the IDCOR Modular Accident Analysis Program, in order to determine the behavior of hydrogen during accident sequences on four reference plants. From these analyses, conditions will be determined so that hydrogen burn control measures can be evaluated. A review is being made of various approaches for suppression of combustion or controlled burning to limit hydrogen to concentrations below the detonation range. The review considers the advantages and disadvantages of various hydrogen control systems concepts for reactor and containment combinations and, in addition, addresses the various concepts for eventual removal of hydrogen from containment

  3. Optimal control system of the intermittent bus-only approach

    Institute of Scientific and Technical Information of China (English)

    Jie Jiang; Yulin Chang

    2014-01-01

    To guarantee bus priority with a minimum impact on car traffic at intersections, an optimal control system of the intermittent bus-only approach (IBA) was proposed. The problems of the existing system are first solved through optimization: the judgment time of the IBA system was advanced to allow a bus to jump car queues if the bus was detected to arrive at the intersection, and the instant that the IBA lane became available to cars was controlled dynamically to increase the capacity of the IBA lane. The total car delay in one cycle was then analyzed quantitatively when implementing the optimal control system. The results show that in comparison with the existing system of the IBA, the car delay is greatly reduced and the probability of a car stopping twice is low after optimizing the IBA system.

  4. Stochastic control approaches for sensor management in search and exploitation

    Science.gov (United States)

    Hitchings, Darin Chester

    Recent improvements in the capabilities of autonomous vehicles have motivated their increased use in such applications as defense, homeland security, environmental monitoring, and surveillance. To enhance performance in these applications, new algorithms are required to control teams of robots autonomously and through limited interactions with human operators. In this dissertation we develop new algorithms for control of robots performing information-seeking missions in unknown environments. These missions require robots to control their sensors in order to discover the presence of objects, keep track of the objects, and learn what these objects are, given a fixed sensing budget. Initially, we investigate control of multiple sensors, with a finite set of sensing options and finite-valued measurements, to locate and classify objects given a limited resource budget. The control problem is formulated as a Partially Observed Markov Decision Problem (POMDP), but its exact solution requires excessive computation. Under the assumption that sensor error statistics are independent and time-invariant, we develop a class of algorithms using Lagrangian Relaxation techniques to obtain optimal mixed strategies using performance bounds developed in previous research. We investigate alternative Receding Horizon (RH) controllers to convert the mixed strategies to feasible adaptive-sensing strategies and evaluate the relative performance of these controllers in simulation. The resulting controllers provide superior performance to alternative algorithms proposed in the literature and obtain solutions to large-scale POMDP problems several orders of magnitude faster than optimal Dynamic Programming (DP) approaches with comparable performance quality. We extend our results for finite action, finite measurement sensor control to scenarios with moving objects. We use Hidden Markov Models (HMMs) for the evolution of objects, according to the dynamics of a birth-death process. We develop a

  5. S-variable approach to LMI-based robust control

    CERN Document Server

    Ebihara, Yoshio; Arzelier, Denis

    2015-01-01

    This book shows how the use of S-variables (SVs) in enhancing the range of problems that can be addressed with the already-versatile linear matrix inequality (LMI) approach to control can, in many cases, be put on a more unified, methodical footing. Beginning with the fundamentals of the SV approach, the text shows how the basic idea can be used for each problem (and when it should not be employed at all). The specific adaptations of the method necessitated by each problem are also detailed. The problems dealt with in the book have the common traits that: analytic closed-form solutions are not available; and LMIs can be applied to produce numerical solutions with a certain amount of conservatism. Typical examples are robustness analysis of linear systems affected by parametric uncertainties and the synthesis of a linear controller satisfying multiple, often  conflicting, design specifications. For problems in which LMI methods produce conservative results, the SV approach is shown to achieve greater accuracy...

  6. Quorum quenching mediated approaches for control of membrane biofouling.

    Science.gov (United States)

    Lade, Harshad; Paul, Diby; Kweon, Ji Hyang

    2014-01-01

    Membrane biofouling is widely acknowledged as the most frequent adverse event in wastewater treatment systems resulting in significant loss of treatment efficiency and economy. Different strategies including physical cleaning and use of antimicrobial chemicals or antibiotics have been tried for reducing membrane biofouling. Such traditional practices are aimed to eradicate biofilms or kill the bacteria involved, but the greater efficacy in membrane performance would be achieved by inhibiting biofouling without interfering with bacterial growth. As a result, the search for environmental friendly non-antibiotic antifouling strategies has received much greater attention among scientific community. The use of quorum quenching natural compounds and enzymes will be a potential approach for control of membrane biofouling. This approach has previously proven useful in diseases and membrane biofouling control by triggering the expression of desired phenotypes. In view of this, the present review is provided to give the updated information on quorum quenching compounds and elucidate the significance of quorum sensing inhibition in control of membrane biofouling.

  7. Control of an electromechanical hydrocephalus shunt--a new approach.

    Science.gov (United States)

    Elixmann, Inga M; Kwiecien, Monika; Goffin, Christine; Walter, Marian; Misgeld, Berno; Kiefer, Michael; Steudel, Wolf-Ingo; Radermacher, Klaus; Leonhardt, Steffen

    2014-09-01

    Hydrocephalus is characterized by an excessive accumulation of cerebrospinal fluid (CSF). Therapeutically, an artificial pressure relief valve (so-called shunt) is implanted which opens in case of increased intracranial pressure (ICP) and drains CSF into another body compartment. Today, available shunts are of a mechanical nature and drainage depends on the pressure drop across the shunt. According to the latest data, craniospinal compliance is considered to be even more important than mean ICP alone. In addition, ICP is not constant but varies due to several influences. In fact, heartbeat-related ICP waveform patterns depend on volume changes in the cranial vessels during a heartbeat and changes its shape as a function of craniospinal compliance. In this paper, we present an electromechanical shunt approach, which changes the CSF drainage as a function of the current ICP waveform. A series of 12 infusion tests in patients were analyzed and revealed a trend between the compliance and specific features of the ICP waveform. For waveform analysis of patient data, an existing signal processing algorithm was improved (using a Moore machine) and was implemented on a low-power microcontroller within the electromechanical shunt. In a test rig, the ICP waveforms were replicated and the decisions of the ICP analysis algorithm were verified. The proposed control algorithm consists of a cascaded integral controller which determines the target ICP from the measured waveform, and a faster inner-loop integral controller that keeps ICP close to the target pressure. Feedforward control using measurement data of the patient's position was implemented to compensate for changes in hydrostatic pressure during change in position. A model-based design procedure was used to lay out controller parameters in a simple model of the cerebrospinal system. Successful simulation results have been obtained with this new approach by keeping ICP within the target range for a healthy waveform.

  8. Robust and optimal control a two-port framework approach

    CERN Document Server

    Tsai, Mi-Ching

    2014-01-01

    A Two-port Framework for Robust and Optimal Control introduces an alternative approach to robust and optimal controller synthesis procedures for linear, time-invariant systems, based on the two-port system widespread in electrical engineering. The novel use of the two-port system in this context allows straightforward engineering-oriented solution-finding procedures to be developed, requiring no mathematics beyond linear algebra. A chain-scattering description provides a unified framework for constructing the stabilizing controller set and for synthesizing H2 optimal and H∞ sub-optimal controllers. Simple yet illustrative examples explain each step. A Two-port Framework for Robust and Optimal Control  features: ·         a hands-on, tutorial-style presentation giving the reader the opportunity to repeat the designs presented and easily to modify them for their own programs; ·         an abundance of examples illustrating the most important steps in robust and optimal design; and ·   �...

  9. Robust motion control of oscillatory-base manipulators h∞-control and sliding-mode-control-based approaches

    CERN Document Server

    Toda, Masayoshi

    2016-01-01

    This book provides readers with alternative robust approaches to control design for an important class of systems characteristically associated with ocean-going vessels and structures. These systems, which include crane vessels, on-board cranes, radar gimbals, and a conductivity temperature and depth winch, are modelled as manipulators with oscillating bases. One design approach is based on the H-infinity control framework exploiting an effective combination of PD control, an extended matrix polytope and a robust stability analysis method with a state-dependent coefficient form. The other is based on sliding-mode control using some novel nonlinear sliding surfaces. The model demonstrates how successful motion control can be achieved by suppressing base oscillations and in the presence of uncertainties. This is important not only for ocean engineering systems in which the problems addressed here originate but more generally as a benchmark platform for robust motion control with disturbance rejection. Researche...

  10. The 4-D approach to visual control of autonomous systems

    Science.gov (United States)

    Dickmanns, Ernst D.

    1994-01-01

    Development of a 4-D approach to dynamic machine vision is described. Core elements of this method are spatio-temporal models oriented towards objects and laws of perspective projection in a foward mode. Integration of multi-sensory measurement data was achieved through spatio-temporal models as invariants for object recognition. Situation assessment and long term predictions were allowed through maintenance of a symbolic 4-D image of processes involving objects. Behavioral capabilities were easily realized by state feedback and feed-foward control.

  11. Matrix converter controlled with the direct transfer function approach

    DEFF Research Database (Denmark)

    Rodriguez, J.; Silva, E.; Blaabjerg, Frede;

    2005-01-01

    Power electronics is an emerging technology. New power circuits are invented and have to be introduced into the power electronics curriculum. One of the interesting new circuits is the matrix converter (MC), and this paper analyses its working principles. A simple model is proposed to represent...... the power circuit, including the input filter. The power semiconductors are modelled as ideal bidirectional switches and the MC is controlled using a direct transfer function approach. The modulation strategy of the converter is explained in a complete and clear form. The commutation problem of two switches...

  12. Data-Driven Controller Design The H2 Approach

    CERN Document Server

    Sanfelice Bazanella, Alexandre; Eckhard, Diego

    2012-01-01

    Data-driven methodologies have recently emerged as an important paradigm alternative to model-based controller design and several such methodologies are formulated as an H2 performance optimization. This book presents a comprehensive theoretical treatment of the H2 approach to data-driven control design. The fundamental properties implied by the H2 problem formulation are analyzed in detail, so that common features to all solutions are identified. Direct methods (VRFT) and iterative methods (IFT, DFT, CbT) are put under a common theoretical framework. The choice of the reference model, the experimental conditions, the optimization method to be used, and several other designer’s choices are crucial to the quality of the final outcome, and firm guidelines for all these choices are derived from the theoretical analysis presented. The practical application of the concepts in the book is illustrated with a large number of practical designs performed for different classes of processes: thermal, fluid processing a...

  13. Temperature Control in Spark Plasma Sintering: An FEM Approach

    Directory of Open Access Journals (Sweden)

    G. Molénat

    2010-01-01

    Full Text Available Powder consolidation assisted by pulsed current and uniaxial pressure, namely, Spark Plasma Sintering (SPS, is increasingly popular. One limitation however lies in the difficulty of controlling the sample temperature during compaction. The aim of this work is to present a computational method for the assembly temperature based on the finite elements method (FEM. Computed temperatures have been compared with experimental data for three different dies filled with three materials with different electrical conductivities (TiAl, SiC, Al2O3. The results obtained are encouraging: the difference between computed and experimental values is less than 5%. This allows thinking about this FEM approach as a predictive tool for selecting the right control temperatures in the SPS machine.

  14. An integrated approach to pipeline buoyancy control and implementation

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, L.N. [AMEC E and C Services Inc., Abbotsford, BC (Canada); Henderson, J. [Associated Mining Consultants Ltd., Vancouver, BC (Canada)

    2004-07-01

    An integrated approach used to solve a complex pipeline design was presented. The problem pipeline was EnCana's Ekwan Pipeline, an NPS 24x83 km long natural gas pipeline in a remote location of northeastern British Columbia where high costs were anticipated for buoyancy control; permafrost protection; and, river crossing construction. This case study demonstrated how to integrate several investigative methods with design, procurement, contracting and construction strategies to reduce life cycles costs considerably for newly constructed operating pipelines. The project design team made use of air photo interpretation, borehole investigation, ground-penetrating radar (GPR), fixed frequency electromagnetics (FEM) and seismic refraction. When each of these methods were integrated effectively with project assessment, design, procurement and construction, the combined data yielded project-specific information that was greater than the sum of individual investigative parts, and significantly reduced construction costs. The best indicator for choosing which buoyancy control method to use was soil types and depths; stability; and, moisture content in the ditch during construction. Pipe buoyancy control design takes into account backfill; ditch and trenching methods; set-on weights; bolt-on weights; concrete coatings; heavy wall pipe; pipe sacks; and, screw anchors. The integrated approach was found to reduce the total amount spent for buoyancy control on the Ekwan Pipeline from a potential 18 per cent of the capital cost to an installed cost of less than 5 per cent of the project total, including all labour, material and data collection methods used. 1 ref., 2 tabs., 12 figs.

  15. RF control at SSCL - an object oriented design approach

    Energy Technology Data Exchange (ETDEWEB)

    Dohan, D.A. (SSCL, MS 4010, 2550 Beckleymeade Ave., Dallas, TX 75237 (United States)); Osberg, E. (SSCL, MS 4010, 2550 Beckleymeade Ave., Dallas, TX 75237 (United States)); Biggs, R. (SSCL, MS 4010, 2550 Beckleymeade Ave., Dallas, TX 75237 (United States)); Bossom, J. (SSCL, MS 4010, 2550 Beckleymeade Ave., Dallas, TX 75237 (United States)); Chillara, K. (SSCL, MS 4010, 2550 Beckleymeade Ave., Dallas, TX 75237 (United States)); Richter, R. (SSCL, MS 4010, 2550 Beckleymeade Ave., Dallas, TX 75237 (United States)); Wade, D. (SSCL, MS 4010, 2550 Beckleymeade Ave., Dallas, TX 75237 (United States))

    1994-12-15

    The Superconducting Super Collider (SSC) in Texas, the construction of which was stopped in 1994, would have represented a major challenge in accelerator research and development. This paper addresses the issues encountered in the parallel design and construction of the control systems for the RF equipment for the five accelerators comprising the SSC. An extensive analysis of the components of the RF control systems has been undertaken, based upon the Schlaer-Mellor object-oriented analysis and design (OOA/OOD) methodology. The RF subsystem components such as amplifiers, tubes, power supplies, PID loops, etc. were analyzed to produce OOA information, behavior and process models. Using these models, OOD was iteratively applied to develop a generic RF control system design. This paper describes the results of this analysis and the development of bridges' between the analysis objects, and the EPICS-based software and underlying VME-based hardware architectures. The application of this approach to several of the SSCL RF control systems is discussed. ((orig.))

  16. RECONFIGURING EVOLVED CIRCUITS USING CONTROLLER: A REAL TIME APPROACH

    Directory of Open Access Journals (Sweden)

    B. Hari Krishna

    2014-01-01

    Full Text Available FPGA is a device that contains a matrix of reconfigurable gate arrays that can implement different complex functions and also vary structurally. In this study, a novel method of reconfigurable circuit switching action is done with the help of a controller. BPSK Modulation application is chosen to demonstrate the reconfigurable action. When an event occurs the context/core switching is done at both input and output and also preserving the structural and functional relationship. The reconfiguration ability of FPGA with an embedded core performing the switching in real time is the focus of this study. A controller running on Linux platform is used along with the FPGA core. In this study, we propose a real time approach for reconfiguring evolved circuits using controller. It has an adaptive hardware that can continuously change in response to the input data and there by perform reconfiguration. Here the reconfiguration process is achieved by using a real time controller which gives a command to the FPGA core (ALTERA (Cypress processor for reconfiguration.

  17. Fault Tolerant Control for Civil Structures Based on LMI Approach

    Directory of Open Access Journals (Sweden)

    Chunxu Qu

    2013-01-01

    Full Text Available The control system may lose the performance to suppress the structural vibration due to the faults in sensors or actuators. This paper designs the filter to perform the fault detection and isolation (FDI and then reforms the control strategy to achieve the fault tolerant control (FTC. The dynamic equation of the structure with active mass damper (AMD is first formulated. Then, an estimated system is built to transform the FDI filter design problem to the static gain optimization problem. The gain is designed to minimize the gap between the estimated system and the practical system, which can be calculated by linear matrix inequality (LMI approach. The FDI filter is finally used to isolate the sensor faults and reform the FTC strategy. The efficiency of FDI and FTC is validated by the numerical simulation of a three-story structure with AMD system with the consideration of sensor faults. The results show that the proposed FDI filter can detect the sensor faults and FTC controller can effectively tolerate the faults and suppress the structural vibration.

  18. THE THEORETHICAL APPROACH AND PRACTICE OF CONTROLLING AND BUSSINESS RISK

    Directory of Open Access Journals (Sweden)

    István HÁGEN

    2015-07-01

    Full Text Available Achieving the controlling approach at the companies has the obvious advantage that it is getting easier to exactly define the strategic and operative objectives, the planning system encourages the increase of performance and the decrease of costs and it helps by comparing plan-fact data. By defining the indices and continuous monitoring it is easier to get the fact data closer to the plans, so in case of careful planning business risk can be reduced. With the application of the controlling approach enterprises can be made economical, efficient and effective, so the activity naturally involving several risks, namely weather conditions, biological hazards, can be made more predictable. To sum up, the application of the Balanced Scorecard at the enterprises on the one hand helps short-term profitability and on the other hand designates what to do to reach long-term financial profitability and competitiveness. The objective of the research was to conduct a survey via questionnaires suitable for analysis as well as relevant deep interviews among the small and medium sized enterprises from different branches in the Carpathian Basin.

  19. Online MTPA Control Approach for Synchronous Reluctance Motor Drives Based on Emotional Controller

    DEFF Research Database (Denmark)

    Daryabeigi, Ehsan; Zarchi, Hossein Abootorabi; Markadeh, G. R. Arab;

    2015-01-01

    In this paper, speed and torque control modes (SCM and TCM) of synchronous reluctance motor (SynRM) drives are proposed based on emotional controllers and space vector modulation under an automatic search of the maximum-torque-per-ampere (MTPA) strategy. Furthermore, in order to achieve an MTPA...... is compared with an optimized conventional PI controller under different operating conditions. Simulation and experimental results demonstrate the benefits of the proposed approach. This structure shows superiority of the proposed method, such as fast dynamic, simple implementation and robustness to parameter...

  20. Hierarchical Control of Droop-Controlled DC and AC Microgrids - A General Approach Towards Standardization

    DEFF Research Database (Denmark)

    Guerrero, Josep M.; Vásquez, Juan V.; Teodorescu, Remus

    2009-01-01

    DC and AC Microgrids are key elements to integrate renewable and distributed energy resources as well as distributed energy storage systems. In the last years, efforts toward the standardization of these Microgrids have been made. In this sense, this paper present the hierarchical control derived...... the deviations produced by the primary control; and iii) the tertiary control manage the power flow between the microgrid and the external electrical distribution system. Results from a hierarchicalcontrolled microgrid are provided to show the feasibility of the proposed approach....

  1. Cyber secure systems approach for NPP digital control systems

    International Nuclear Information System (INIS)

    Whether fossil or nuclear power, the chief operations goal is to generate electricity. The heart of most plant operations is the I and C system. With the march towards open architecture, the I and C system is more vulnerable than ever to system security attacks (denial of service, virus attacks and others), thus jeopardizing plant operations. Plant staff must spend large amounts of time and money setting up and monitoring a variety of security strategies to counter the threats and actual attacks to the system. This time and money is a drain on the financial performance of a plant and distracts valuable operations resources from their real goals: product. The pendulum towards complete open architecture may have swung too far. Not all aspects of proprietary hardware and software are necessarily 'bad'. As the aging U.S. fleet of nuclear power plants starts to engage in replacing legacy control systems, and given the on-going (and legitimate) concern about the security of present digital control systems, decisions about how best to approach cyber security are vital to the specification and selection of control system vendors for these upgrades. The authors maintain that utilizing certain resources available in today's digital technology, plant control systems can be configured from the onset to be inherently safe, so that plant staff can concentrate on the operational issues of the plant. The authors postulate the concept of the plant I and C being bounded in a 'Cyber Security Zone' and present a design approach that can alleviate the concern and cost at the plant level of dealing with system security strategies. Present approaches through various IT cyber strategies, commercial software, and even postulated standards from various industry/trade organizations are almost entirely reactive and simply add to cost and complexity. This Cyber Security Zone design demonstrates protection from the four classes of cyber security attacks: 1)Threat from an intruder attempting to

  2. Controlled Chemistry Approach to the Oxo-Functionalization of Graphene.

    Science.gov (United States)

    Eigler, Siegfried

    2016-05-17

    Graphene is the best-studied 2D material available. However, its production is still challenging and the quality depends on the preparation procedure. Now, more than a decade after the outstanding experiments conducted on graphene, the most successful wet-chemical approach to graphene and functionalized graphene is based on the oxidation of graphite. Graphene oxide has been known for more than a century; however, the structure bears variable large amounts of lattice defects that render the development of a controlled chemistry impossible. The controlled oxo-functionalization of graphene avoids the formation of defects within the σ-framework of carbon atoms, making the synthesis of specific molecular architectures possible. The scope of this review is to introduce the field of oxo-functionalizing graphene. In particular, the differences between GO and oxo-functionalized graphene are described in detail. Moreover analytical methods that allow determining lattice defects and functional groups are introduced followed by summarizing the current state of controlled oxo-functionalization of graphene. PMID:26990805

  3. The Difficult-to-Control Asthmatic: A Systematic Approach

    Directory of Open Access Journals (Sweden)

    Le Annie V

    2006-09-01

    Full Text Available Abstract With the judicious use of inhaled corticosteroids, β2 agonists, and leukotriene modifiers, most patients with asthma are easily controlled and managed. However, approximately 5% of asthmatics do not respond to standard therapy and are classified as "difficult to control." 1 Typically, these are patients who complain of symptoms interfering with daily living despite long-term treatment with inhaled corticosteroids in doses up to 2,000 μg daily. Many factors can contribute to poor response to conventional therapy, and especially for these patients, a systematic approach is needed to identify the underlying causes. First, the diagnosis of asthma and adherence to the medication regimen should be confirmed. Next, potential persisting exacerbating triggers need to be identified and addressed. Concomitant disorders should be discovered and treated. Lastly, the impact and implications of socioeconomic and psychological factors on disease control can be significant and should be acknowledged and discussed with the individual patient. Less conventional and novel strategies for treating corticosteroid-resistant asthma do exist. However, their use is based on small studies that do not meet evidence-based criteria; therefore, it is essential to sort through and address the above issues before reverting to other therapy.

  4. An Approach to Discrete Variable Structure Control System

    Institute of Scientific and Technical Information of China (English)

    FalahE.Alsaqre; YUANBaozong

    2003-01-01

    Variable structure control (VSC) systems consist of a set of subsystems referred to as structures and supplied with appropriate switching functions. The most common approach used for variable structure in continu-ous or discrete time systems is sliding mode. In this paper,a new scheme to design a discrete variable structure con-trol (DVSC) for an nth-order type one system is presented.First, a set of discrete subsystems is constructed relying on the assumption that every system is considered as a vari-able structure system when its poles can be assignment to other locations. The adopted method for constructing dif-ferent discrete structures involves switching alternatively two zero-order hold (ZOH) devices, having different char-acteristics. Second, a suitable switching function is devised based on minimizing a quadratic sum of discrete error sig-nal criterion, to perform one switching without chattering.New advantageous properties are carried out via compos-ing a desired performance from parts of performances of the constructed structures. Simulation results are made to illustrate the quality of control being achieved.

  5. Autonomous formation flight of helicopters: Model predictive control approach

    Science.gov (United States)

    Chung, Hoam

    Formation flight is the primary movement technique for teams of helicopters. However, the potential for accidents is greatly increased when helicopter teams are required to fly in tight formations and under harsh conditions. This dissertation proposes that the automation of helicopter formations is a realistic solution capable of alleviating risks. Helicopter formation flight operations in battlefield situations are highly dynamic and dangerous, and, therefore, we maintain that both a high-level formation management system and a distributed coordinated control algorithm should be implemented to help ensure safe formations. The starting point for safe autonomous formation flights is to design a distributed control law attenuating external disturbances coming into a formation, so that each vehicle can safely maintain sufficient clearance between it and all other vehicles. While conventional methods are limited to homogeneous formations, our decentralized model predictive control (MPC) approach allows for heterogeneity in a formation. In order to avoid the conservative nature inherent in distributed MPC algorithms, we begin by designing a stable MPC for individual vehicles, and then introducing carefully designed inter-agent coupling terms in a performance index. Thus the proposed algorithm works in a decentralized manner, and can be applied to the problem of helicopter formations comprised of heterogenous vehicles. Individual vehicles in a team may be confronted by various emerging situations that will require the capability for in-flight reconfiguration. We propose the concept of a formation manager to manage separation, join, and synchronization of flight course changes. The formation manager accepts an operator's commands, information from neighboring vehicles, and its own vehicle states. Inside the formation manager, there are multiple modes and complex mode switchings represented as a finite state machine (FSM). Based on the current mode and collected

  6. A hybrid approach to modeling and control of vehicle height for electronically controlled air suspension

    Science.gov (United States)

    Sun, Xiaoqiang; Cai, Yingfeng; Wang, Shaohua; Liu, Yanling; Chen, Long

    2016-01-01

    The control problems associated with vehicle height adjustment of electronically controlled air suspension (ECAS) still pose theoretical challenges for researchers, which manifest themselves in the publications on this subject over the last years. This paper deals with modeling and control of a vehicle height adjustment system for ECAS, which is an example of a hybrid dynamical system due to the coexistence and coupling of continuous variables and discrete events. A mixed logical dynamical (MLD) modeling approach is chosen for capturing enough details of the vehicle height adjustment process. The hybrid dynamic model is constructed on the basis of some assumptions and piecewise linear approximation for components nonlinearities. Then, the on-off statuses of solenoid valves and the piecewise approximation process are described by propositional logic, and the hybrid system is transformed into the set of linear mixed-integer equalities and inequalities, denoted as MLD model, automatically by HYSDEL. Using this model, a hybrid model predictive controller (HMPC) is tuned based on online mixed-integer quadratic optimization (MIQP). Two different scenarios are considered in the simulation, whose results verify the height adjustment effectiveness of the proposed approach. Explicit solutions of the controller are computed to control the vehicle height adjustment system in realtime using an offline multi-parametric programming technology (MPT), thus convert the controller into an equivalent explicit piecewise affine form. Finally, bench experiments for vehicle height lifting, holding and lowering procedures are conducted, which demonstrate that the HMPC can adjust the vehicle height by controlling the on-off statuses of solenoid valves directly. This research proposes a new modeling and control method for vehicle height adjustment of ECAS, which leads to a closed-loop system with favorable dynamical properties.

  7. Biogas Production Modelling: A Control System Engineering Approach

    Science.gov (United States)

    Stollenwerk, D.; Rieke, C.; Dahmen, M.; Pieper, M.

    2016-03-01

    Due to the Renewable Energy Act, in Germany it is planned to increase the amount of renewable energy carriers up to 60%. One of the main problems is the fluctuating supply of wind and solar energy. Here biogas plants provide a solution, because a demand-driven supply is possible. Before running such a plant, it is necessary to simulate and optimize the process feeding strategy. Current simulation models are either very detailed like the ADM 1, which leads to very long optimization runtimes or not accurate enough to handle the biogas production kinetics. Therefore this paper provides a new model of a biogas plant, which is easy to parametrize but also has the needed accuracy for the output prediction. It is based on the control system approach of system identification and validated with laboratory results of a real biogas production testing facility.

  8. Neural Network Approach to Railway Stand Lateral SKEW Control

    Directory of Open Access Journals (Sweden)

    Peter Mark Benes

    2014-02-01

    Full Text Available The paper presents a study of an adaptive approach to lateral skew co ntrol for an experimental railway stand. The preliminary experiments with the real ex perimental railway stand and simulations with its 3-D mechanical model, indicates difficulties of model-based control of the device. Thus, use of neural networks for identification and c ontrol of lateral skew shall be investigated. This paper focuses on real-data based modelling of the railway stand by various neural network models, i.e; linear neural unit and quadratic neur al unit architectures. Furthermore, training methods of these neural architecture s as such, real-time-recurrent- learning and a variation of back-propagation-through-time are exam ined, accompanied by a discussion of the produced experimental results

  9. A fuzzy behaviorist approach to sensor-based robot control

    Energy Technology Data Exchange (ETDEWEB)

    Pin, F.G.

    1996-05-01

    Sensor-based operation of autonomous robots in unstructured and/or outdoor environments has revealed to be an extremely challenging problem, mainly because of the difficulties encountered when attempting to represent the many uncertainties which are always present in the real world. These uncertainties are primarily due to sensor imprecisions and unpredictability of the environment, i.e., lack of full knowledge of the environment characteristics and dynamics. An approach. which we have named the {open_quotes}Fuzzy Behaviorist Approach{close_quotes} (FBA) is proposed in an attempt to remedy some of these difficulties. This approach is based on the representation of the system`s uncertainties using Fuzzy Set Theory-based approximations and on the representation of the reasoning and control schemes as sets of elemental behaviors. Using the FBA, a formalism for rule base development and an automated generator of fuzzy rules have been developed. This automated system can automatically construct the set of membership functions corresponding to fuzzy behaviors. Once these have been expressed in qualitative terms by the user. The system also checks for completeness of the rule base and for non-redundancy of the rules (which has traditionally been a major hurdle in rule base development). Two major conceptual features, the suppression and inhibition mechanisms which allow to express a dominance between behaviors are discussed in detail. Some experimental results obtained with the automated fuzzy, rule generator applied to the domain of sensor-based navigation in aprion unknown environments. using one of our autonomous test-bed robots as well as a real car in outdoor environments, are then reviewed and discussed to illustrate the feasibility of large-scale automatic fuzzy rule generation using the {open_quotes}Fuzzy Behaviorist{close_quotes} concepts.

  10. A rapid approach to rational water pollution control strategies.

    Science.gov (United States)

    Economopoulos, A P

    1996-10-01

    The formulation of rational wastewater control strategies is becoming increasingly important in many countries where, exploding urbanization, industrialization and/or tourism, often combined with improved standards of living and better awareness of the environmental problems, are resulting in enlarged pollution problems, but also in the availability of expanding financial resources for environmental protection. However, more often than one tends to believe, lack of planning, or planning with limited understanding of the principles involved, has resulted in solutions that are both expensive and incapable of addressing the key problems.As rigorous planning is extremely resource intensive, and for this reason impractical for most study areas, the development of a much simplified analysis procedure, capable of generating rational, near-optimum, strategies and detailed action programs, is required, if proper environmental management is to be widely practiced.In an effort to achieve the above objectives, a systems analysis approach is selected as the most suitable at rationalizing the allocation of available resources and at producing detailed action programs that promote implementation. In the context of this approach, new, easy to use models have been developed, while others, have been selected, adapted and streamlined in their use. The entire problem analysis and strategy synthesis procedures have thus been simplified and defined to a degree appropriate for widespread use, and the resultant procedure is actively promoted by WHO and UNEP.

  11. Ultrasensitive Negative Feedback Control: A Natural Approach for the Design of Synthetic Controllers

    Science.gov (United States)

    Montefusco, Francesco; Akman, Ozgur E.; Soyer, Orkun S.; Bates, Declan G.

    2016-01-01

    Many of the most important potential applications of Synthetic Biology will require the ability to design and implement high performance feedback control systems that can accurately regulate the dynamics of multiple molecular species within the cell. Here, we argue that the use of design strategies based on combining ultrasensitive response dynamics with negative feedback represents a natural approach to this problem that fully exploits the strongly nonlinear nature of cellular information processing. We propose that such feedback mechanisms can explain the adaptive responses observed in one of the most widely studied biomolecular feedback systems—the yeast osmoregulatory response network. Based on our analysis of such system, we identify strong links with a well-known branch of mathematical systems theory from the field of Control Engineering, known as Sliding Mode Control. These insights allow us to develop design guidelines that can inform the construction of feedback controllers for synthetic biological systems. PMID:27537373

  12. ECONOMIC APPROACH FOR CONTROL AGRICULTURAL NONPOINT SOURCE POLLUTION IN CHINA

    Institute of Scientific and Technical Information of China (English)

    WANG Xiao-yan; CAO Li-ping

    2005-01-01

    This paper mainly discusses the feasibility to establish economic policy systems for control and management of agricultural nonpoint source pollution in China. The current situation of serious agricultural nonpoint source pollution in China is described firstly. Based on the environmental policy and economics theories, the system of economic policies for control and management of agricultural nonpoint source pollution is designed in this paper. This system includes the policy objective, the designing principle and the methods. The key issues include pollution charge,inputs tax for restriction, subsides for induction and incentive, effluent trading for least cost reduction. The emphases are optimized on inputs tax and agricultural chemical tax permit under complete information, as well as sub-optimized inputs tax under incomplete information, subsides for farm due to positive and negative externality. The functions and suitability of the policies are also analyzed in the paper. According to the field experiment results and other relating economic data in watershed of the Chaohe River, Beijing, some economic approaches to reducing agricultural nonpoint source pollution are proposed. The main idea is to encourage and support the farmers to improve their farming way,and to implement the policy of castigating charge simultaneously. The feasibility of the policies are analyzed with consideration of economy, technology and institution. It is concluded that the economic policies are necessary and feasible.

  13. AMAZON RAINFOREST COSMETICS: CHEMICAL APPROACH FOR QUALITY CONTROL

    Directory of Open Access Journals (Sweden)

    Mariko Funasaki

    2016-02-01

    Full Text Available The market for natural cosmetics featuring ingredients derived from Amazon natural resources is growing worldwide. However, there is neither enough scientific basis nor quality control of these ingredients. This paper is an account of the chemical constituents and their biological activities of fourteen Amazonian species used in cosmetic industry, including açaí (Euterpe oleracea, andiroba (Carapa guianensis, bacuri (Platonia insignis, Brazil nut (Bertholletia excelsa, buriti (Mauritia vinifera or M. flexuosa, cumaru (Dipteryx odorata, cupuaçu (Theobroma grandiflorum, guarana (Paullinia cupana, mulateiro (Calycophyllum spruceanum, murumuru (Astrocaryum murumuru, patawa (Oenocarpus bataua or Jessenia bataua, pracaxi (Pentaclethra macroloba, rosewood (Aniba rosaeodora, and ucuuba (Virola sebifera. Based on the reviewed articles, we selected chemical markers for the quality control purpose and evaluated analytical methods. Even though chromatographic and spectroscopic methods are major analytical techniques in the studies of these species, molecular approaches will also be important as used in food and medicine traceability. Only a little phytochemical study is available about most of the Amazonian species and some species such as açaí and andiroba have many reports on chemical constituents, but studies on biological activities of isolated compounds and sampling with geographical variation are limited.

  14. Dynamic programming approach for newborn's incubator humidity control.

    Science.gov (United States)

    Bouattoura, D; Villon, P; Farges, G

    1998-01-01

    The anatomy, physiology, and biochemistry of the human skin have been studied for a long time. A special interest has been shown in the water permeability of the premature infant's skin, which is known to be an important factor in the maintenance of a controlled water and heat balance. The rate of evaporative heat exchange between the skin surface of a very premature infant and the surrounding incubator air may be so high that evaporative heat loss alone may exceed the infant's total metabolic heat production. However, it has been demonstrated in several investigations published in recent years that basal evaporative water loss can be consistently reduced by increasing the ambient humidity. Nevertheless, the passive humidification system (water reservoir) used in most incubators cannot achieve high and steady humidity levels. In this paper, we propose an active humidification system. The algorithm is based on a combination of optimal control theory and dynamic programming approach. The relative-humidity (R.H.) regulation is performed in range of 35-90% at 33 degrees C with small oscillations (+/- 0.5% R.H.) around the reference value (i.e., prescribed R.H.).

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

    Science.gov (United States)

    Yen Nakafuji, Dora; van Dam, Cornelis

    2001-11-01

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

  16. Measurement approaches to support future warhead arms control transparency

    International Nuclear Information System (INIS)

    Transparency on warhead stockpiles, warhead dismantlement, and fissile material stockpiles in nuclear weapons states will become increasingly important in the move beyond START II toward lower quantities of warheads. Congressional support for further warhead reductions will likely depend on the degree of irreversibility, or in other words, the rapidity with which warhead inventories could be reconstituted. Whether irreversibility considerations can be satisfied will depend on monitoring dismantlement as well as constraining the available stockpile of fissile materials for possible refabrication into warheads. Measurement techniques designed to address the above problems will need to consider NPT Article 1 obligations as well as Russian and US classification regulations, which prohibit or restrict the transfer of nuclear warhead design information to other states. Classification considerations currently limit the potential completeness of future inspections of weapons materials. Many conventional international safeguards approaches are not currently viable for arms control applications because they would reveal weapons design information. The authors discuss a variety of technical measures that may help to improve transparence of warhead and fissile material stockpiles and may enable limited warhead dismantlement transparency

  17. Metadata Control Agent approach for Replication in Grid Environments

    Directory of Open Access Journals (Sweden)

    P. SunilGavaskar

    2013-10-01

    Full Text Available since grid environment is dynamic, network latency and user requests may change. In order to provide better communication, access time and fault tolerant in decentralized systems, the replication is a technique to reduce access time, storage space. The objective of the work is to propose an agent control approach for Heterogeneous environments using the Agents for storing objects as replicas in decentralized environments. Our idea minimizes the more replicas (i.e. causes overhead on response time and update cost, therefore maintaining suitable number of replicas is important. Fixed replicas provides file access structure to identify the esteem files and gives optimal replication location, which minimize replication issues like access time and update cost by assuming a given traffic pattern. In this context we present the Agents as replicas to maintain a suitable scalable architecture. The solution uses fewer replicas, which lead to fewer agents as a result of that frequent updating is possible. Our tests show that the proposed strategy outperforms previous solutions in terms of replication issues.

  18. Arms control and disarmament: A new conceptual approach

    International Nuclear Information System (INIS)

    In the frame of the Millennium Assembly of the UN, the Secretary-General urged the global community to seize a sense of the occasion that comes from the turning of the century, to step back from today's headlines and take a broader, longer-term view of the state of the world and the challenges it poses. In partnership with the Stockholm International Peace Research Institute (SIPRI), the Department for Disarmament Affairs (DDA) is taking up precisely that challenge. This panel discussion is part of a series of events sponsored by the Department to deepen the discussion on topical disarmament and security related issues. It is also part of the constant search for a new approach, a new concept, a new paradigm or vision for disarmament and arms control since the end of the cold war, the end of the post-cold war period and the beginning of the new century. It is axiomatic that progress in disarmament is closely linked to the evolution of the security environment. Disarmament cannot be separated from the new geo-political and security configurations in Europe, new demonstrations of nuclear capability in Asia, the emergence of new conflicts that are being driven mainly by internal and ethnic strife and that are outrageous in their brutality in Europe, Asia and Africa. Today's agenda is still full and diverse in the traditional areas of disarmament, nuclear, chemical and biological disarmament as well as ballistic missile defense and proliferation and conventional disarmament including landmines. Like many organizations, research institutes, researchers and individuals in the field of security, DDA has set store on the reliability and credibility of the research and publications produced by SIPRI. As an independent international institute for research on problems for peace and conflict, disarmament and arms control founded in 1966, SIPRI's primary research has been consistently objective, timely, comprehensive and clearly presented. SIPRI's Yearbook has been a reference

  19. STABILIZATION OF NONLINEAR TIME-VARYING SYSTEMS: A CONTROL LYAPUNOV FUNCTION APPROACH

    Institute of Scientific and Technical Information of China (English)

    Zhongping JIANG; Yuandan LIN; Yuan WANG

    2009-01-01

    This paper presents a control Lyapunov function approach to the global stabilization problem for general nonlinear and time-varying systems. Explicit stabilizing feedback control laws are proposed based on the method of control Lyapunov functions and Sontag's universal formula.

  20. Visual control of wheeled mobile robots unifying vision and control in generic approaches

    CERN Document Server

    Becerra, Héctor M

    2014-01-01

    Vision-based control of wheeled mobile robots is an interesting field of research from a scientific and even social point of view due to its potential applicability. This book presents a formal treatment of some aspects of control theory applied to the problem of vision-based pose regulation of wheeled mobile robots. In this problem, the robot has to reach a desired position and orientation, which are specified by a target image. It is faced in such a way that vision and control are unified to achieve stability of the closed loop, a large region of convergence, without local minima, and good robustness against parametric uncertainty. Three different control schemes that rely on monocular vision as unique sensor are presented and evaluated experimentally. A common benefit of these approaches is that they are valid for imaging systems obeying approximately a central projection model, e.g., conventional cameras, catadioptric systems and some fisheye cameras. Thus, the presented control schemes are generic approa...

  1. A model–based approach to fault–tolerant control

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik

    2012-01-01

    reconfiguration part. The theoretical basis for the architecture is given followed by an investigation of the single parts in the architecture. It is shown that the general controller parameterization is central in connection with both fault diagnosis as well as controller reconfiguration. Especially in relation......A model-based controller architecture for Fault-Tolerant Control (FTC) is presented in this paper. The controller architecture is based on a general controller parameterization. The FTC architecture consists of two main parts, a Fault Detection and Isolation (FDI) part and a controller...... to the controller reconfiguration part, the application of controller parameterization results in a systematic technique for switching between different controllers. This also allows controller switching using different sets of actuators and sensors....

  2. A new approach to process control using Instability Index

    Science.gov (United States)

    Weintraub, Jeffrey; Warrick, Scott

    2016-03-01

    The merits of a robust Statistical Process Control (SPC) methodology have long been established. In response to the numerous SPC rule combinations, processes, and the high cost of containment, the Instability Index (ISTAB) is presented as a tool for managing these complexities. ISTAB focuses limited resources on key issues and provides a window into the stability of manufacturing operations. ISTAB takes advantage of the statistical nature of processes by comparing the observed average run length (OARL) to the expected run length (ARL), resulting in a gap value called the ISTAB index. The ISTAB index has three characteristic behaviors that are indicative of defects in an SPC instance. Case 1: The observed average run length is excessively long relative to expectation. ISTAB > 0 is indicating the possibility that the limits are too wide. Case 2: The observed average run length is consistent with expectation. ISTAB near zero is indicating that the process is stable. Case 3: The observed average run length is inordinately short relative to expectation. ISTAB process is unstable or both. The probability distribution of run length is the basis for establishing an ARL. We demonstrate that the geometric distribution is a good approximation to run length across a wide variety of rule sets. Excessively long run lengths are associated with one kind of defect in an SPC instance; inordinately short run lengths are associated with another. A sampling distribution is introduced as a way to quantify excessively long and inordinately short observed run lengths. This paper provides detailed guidance for action limits on these run lengths. ISTAB as a statistical method of review facilitates automated instability detection. This paper proposes a management system based on ISTAB as an enhancement to more traditional SPC approaches.

  3. An efficient stakeholder driven approach to disease control

    International Nuclear Information System (INIS)

    least amount of time. Critical to this concept is the need to identify and prioritise the most important gaps in our ability to control the critical diseases. Having identified our targets, it is then vital that we have the fundamental research capacity - infrastructure and people to carry out the necessary research. Establishing our research capability necessitates the creation of a database with the relevant information with gaps then being addressed. Along with filling gaps, efficiency can also be improved by avoiding unnecessary capacity development. Enabling factors such as quality assurance, intellectual property rights and facilitation of technology transfer are critical components in moving from basic research to the development of a tool that can be used to fight a disease. Financial support at critical points in the development chain is also vital. Too often, projects are dropped because intellectual property rights have not been secured and nobody is willing to invest perhaps Euro 100 million in taking the project from the laboratory bench through development and into the market. The correct regulatory environment is vital to stimulate innovation. A balance needs to be reached between protecting human and animal health from the risks associated with a product versus the wish to eliminate all hazard. In addition, regulation needs to be focused on the needs of the veterinary sector, which may be quite different to those of the human sector. From a global perspective, it is in the interests of everybody to reduce the global burden of disease. It may be much more beneficial to tackle disease at its source. This approach facilitates cooperation across the globe including capacity building. Having explored the broad areas that need attention in the SRA, the Action Plan was then developed and published in July, 2007 identifying the actions - research or information gathering - that need to be carried out in order to deliver the SRA. The Action Plan follows the

  4. Distributed Secondary Control for Islanded MicroGrids - A Novel Approach

    DEFF Research Database (Denmark)

    Shafiee, Qobad; Guerrero, Josep M.; Vasquez, Juan Carlos

    2014-01-01

    This paper presents a novel approach to conceive the secondary control in droop-controlled MicroGrids. The conventional approach is based on restoring the frequency and amplitude deviations produced by the local droop controllers by using a MicroGrid Central Controller (MGCC). A distributed...... networked control system is used in order to implement a distributed secondary control (DSC) thus avoiding its implementation in MGCC. The proposed approach is not only able to restore frequency and voltage of the MicroGrid but also ensures reactive power sharing. The distributed secondary control does...

  5. A first approach to runaway electron control in FTU

    Energy Technology Data Exchange (ETDEWEB)

    Boncagni, L. [Associazione Euratom/ENEA sulla Fusione, Centro Ricerche Frascati, CP 65, 00044 Frascati, Roma (Italy); Carnevale, D., E-mail: carnevaledaniele@gmail.com [Dipartimento Ing. Civile ed Ing. Informatica Università di Roma, Tor Vergata, Via del Politecnico 1, 00133 Roma (Italy); Cianfarani, C.; Esposito, B. [Associazione Euratom/ENEA sulla Fusione, Centro Ricerche Frascati, CP 65, 00044 Frascati, Roma (Italy); Granucci, G. [Associazione Euratom-CNR sulla Fusione, IFP-CNR, Via R. Cozzi 53, 20125 Milano (Italy); Maddaluno, G.; Marocco, D. [Associazione Euratom/ENEA sulla Fusione, Centro Ricerche Frascati, CP 65, 00044 Frascati, Roma (Italy); Martin-Solis, J.R. [Universidad Carlos III de Madrid, Avda. de la Universidad 30, 28911 Leganes-Madrid (Spain); Pucella, G. [Associazione Euratom/ENEA sulla Fusione, Centro Ricerche Frascati, CP 65, 00044 Frascati, Roma (Italy); Sozzi, C. [Associazione Euratom-CNR sulla Fusione, IFP-CNR, Via R. Cozzi 53, 20125 Milano (Italy); Varano, G. [Dipartimento Ing. Civile ed Ing. Informatica Università di Roma, Tor Vergata, Via del Politecnico 1, 00133 Roma (Italy); Vitale, V. [Associazione Euratom/ENEA sulla Fusione, Centro Ricerche Frascati, CP 65, 00044 Frascati, Roma (Italy); Zaccarian, L. [CNRS, LAAS, 7 av. du colonel Roche, F-31400 Toulouse (France); Univ. de Toulouse, LAAS, F-31400 Toulouse (France)

    2013-10-15

    The Plasma Control System (PCS) of the Frascati Tokamak Upgrade (FTU) is not equipped with any runaway electron (RE) beam control or suppression tool. In this paper we propose an upgraded PCS including an architecture for the control of disruption-generated REs that, making use of filtering techniques to estimate the onsets of the current quench (CQ) and of the RE beam current plateau, provides a controlled plasma current shut-down and a simultaneous RE position control. The control strategy is based on a nonlinear technique, called Input Allocation, that allows to re-configure the current in the poloidal field (PF) coils and improve the PCS responsiveness needed for RE position control. Preliminary results on the implementation of the Input Allocation and an experimental proposal to test the control scheme architecture are discussed.

  6. A new approach to a site radiological control manual.

    Science.gov (United States)

    Farrell, Linda M

    2002-02-01

    The Pantex Plant significantly revised its Radiological Control Manual to improve its usability, streamline plant procedures, and clarify conflicting guidance. This article overviews the process used to develop the new Radiological Control Manual. PMID:11797900

  7. Composite Fuzzy Logic Control Approach to a Flexible Joint Manipulator

    Directory of Open Access Journals (Sweden)

    Mohd Ashraf Ahmad

    2013-01-01

    Full Text Available The raised complicatedness of the dynamics of a robot manipulator considering joint elasticity makes conventional model‐based control strategies complex and hard to synthesize. This paper presents investigations into the development of hybrid intelligent control schemes for the trajectory tracking and vibration control of a flexible joint manipulator. To study the effectiveness of the controllers, a collocated proportional‐derivative (PD‐type Fuzzy Logic Controller (FLC is first developed for the tip angular position control of a flexible joint manipulator. This is then extended to incorporate a non‐collocated Fuzzy Logic Controller, a non‐collocated proportional‐ integral‐derivative (PID and an input‐shaping scheme for the vibration reduction of the flexible joint system. The positive zero‐vibration‐derivative‐derivative (ZVDD shaper is designed based on the properties of the system. The implementation results of the response of the flexible joint manipulator with the controllers are presented in time and frequency domains. The performances of the hybrid control schemes are examined in terms of input tracking capability, level of vibration reduction and time response specifications. Finally, a comparative assessment of the control techniques is presented and discussed.

  8. Quality control with R an ISO standards approach

    CERN Document Server

    Cano, Emilio L; Prieto Corcoba, Mariano

    2015-01-01

    Presenting a practitioner's guide to capabilities and best practices of quality control systems using the R programming language, this volume emphasizes accessibility and ease-of-use through detailed explanations of R code as well as standard statistical methodologies. In the interest of reaching the widest possible audience of quality-control professionals and statisticians, examples throughout are structured to simplify complex equations and data structures, and to demonstrate their applications to quality control processes, such as ISO standards. The volume balances its treatment of key aspects of quality control, statistics, and programming in R, making the text accessible to beginners and expert quality control professionals alike. Several appendices serve as useful references for ISO standards and common tasks performed while applying quality control with R.

  9. A hamiltonian control approach for the stabilization of the angular velocity of a rigid body system controlled by two torques

    OpenAIRE

    C. Aguilar-Ibáñez; M.S. Suárez-Castañón; F. Guzmán-Aguilar

    2008-01-01

    We present a Hamiltonian control approach for the stabilization of a rigid body system that is controlled by two torques. The stabilization strategy consists in solving a feasible matching condition in order to derive a feedback controller which forces the closed-loop system to be globally asymptotically stable.

  10. An Ecological Approach to the Supervisory Control of UAV Swarms

    NARCIS (Netherlands)

    Fuchs, C.; Borst, C.; De Croon, G.C.H.E.; Van Paassen, M.M.; Mulder, M.

    2014-01-01

    This research employs ecological interface design to improve the human machine interface of an existing ground control station for the supervisory control of UAV swarms. As a case study, a general ground surveillance mission with four UAVs is envisioned. An analysis of the swarming work domain is pe

  11. A fuzzy logic approach to control anaerobic digestion

    NARCIS (Netherlands)

    Domnanovich, A.M.; Strik, D.P.B.T.B.; Pfeiffer, B.; Karlovits, M.; Zani, L.; Braun, R.; Holubar, P.

    2003-01-01

    One of the goals of the EU-Project AMONCO (Advanced Prediction, Monitoring and Controlling of Anaerobic Digestion Process Behaviour towards Biogas Usage in Fuel Cells) is to create a control tool for the anaerobic digestion process, which predicts the volumetric organic loading rate (Bv) for the nex

  12. Hybrid-impulsive second order sliding mode control: Lyapunov approach

    NARCIS (Netherlands)

    Shtessel, Y.; Glumineau, A.; Plestan, F.; Weiss, M.

    2013-01-01

    A perturbed nonlinear system of relative degree two controlled by discontinuous-impulsive feedbacks is studied. The hybrid-impulsive terms serve to drive instantaneously the system trajectories to the origin or to its small vicinity. In particular, impulsive-twisting control exhibits an uniform exac

  13. Artificial Intelligence Approach to Support Statistical Quality Control Teaching

    Science.gov (United States)

    Reis, Marcelo Menezes; Paladini, Edson Pacheco; Khator, Suresh; Sommer, Willy Arno

    2006-01-01

    Statistical quality control--SQC (consisting of Statistical Process Control, Process Capability Studies, Acceptance Sampling and Design of Experiments) is a very important tool to obtain, maintain and improve the Quality level of goods and services produced by an organization. Despite its importance, and the fact that it is taught in technical and…

  14. A passivity approach to controller-observer design for robots

    NARCIS (Netherlands)

    Berghuis, Harry; Nijmeijer, Henk

    1993-01-01

    Passivity-based control methods for robots, which achieve the control objective by reshaping the robot system's natural energy via state feedback, have, from a practical point of view, some very attractive properties. However, the poor quality of velocity measurements may significantly deteriorate t

  15. Dynamics and Control of Humanoid Robots: A Geometrical Approach

    CERN Document Server

    Ivancevic, Vladimir G

    2011-01-01

    his paper reviews modern geometrical dynamics and control of humanoid robots. This general Lagrangian and Hamiltonian formalism starts with a proper definition of humanoid's configuration manifold, which is a set of all robot's active joint angles. Based on the `covariant force law', the general humanoid's dynamics and control are developed. Autonomous Lagrangian dynamics is formulated on the associated `humanoid velocity phase space', while autonomous Hamiltonian dynamics is formulated on the associated `humanoid momentum phase space'. Neural-like hierarchical humanoid control naturally follows this geometrical prescription. This purely rotational and autonomous dynamics and control is then generalized into the framework of modern non-autonomous biomechanics, defining the Hamiltonian fitness function. The paper concludes with several simulation examples. Keywords: Humanoid robots, Lagrangian and Hamiltonian formalisms, neural-like humanoid control, time-dependent biodynamics

  16. A systematic approach for fine-tuning of fuzzy controllers applied to WWTPs

    DEFF Research Database (Denmark)

    Ruano, M.V.; Ribes, J.; Sin, Gürkan;

    2010-01-01

    A systematic approach for fine-tuning fuzzy controllers has been developed and evaluated for an aeration control system implemented in a WWTR The challenge with the application of fuzzy controllers to WWTPs is simply that they contain many parameters, which need to be adjusted for different WWTP ......-consuming and tedious trial and error approach currently used in practice. (C) 2009 Elsevier Ltd. All rights reserved.......A systematic approach for fine-tuning fuzzy controllers has been developed and evaluated for an aeration control system implemented in a WWTR The challenge with the application of fuzzy controllers to WWTPs is simply that they contain many parameters, which need to be adjusted for different WWTP......: to fine-tune the identifiable parameter subset of the controller. Indeed, the initial location found by Monte-Carlo simulations provided better results than using trial and error approach when identifying parameters of the fuzzy controller. The identifiable subset was reduced to 4 parameters from a total...

  17. Manual control displays for a four-dimensional landing approach

    Science.gov (United States)

    Silverthorn, J. T.; Swaim, R. L.

    1975-01-01

    Six instrument rated pilots flew a STOL fixed base simulator to study the effectiveness of three displays for a four dimensional approach. The three examined displays were a digital readout of forward position error, a digital speed command, and an analog display showing forward position error and error prediction. A flight director was used in all conditions. All test runs were for a typical four dimensional approach in moderate turbulence that included a change in commanded ground speed, a change in flight path angle, and two standard rate sixty degree turns. Use of the digital forward position error display resulted in large overshoot in the forward position error. Some type of lead (rate or prediction information) was shown to be needed. The best overall performance was obtained using the speed command display. It was demonstrated that curved approaches can be flown with relative ease.

  18. Flexographic Printing and Integral Approach to Pollution Prevention and Control

    Directory of Open Access Journals (Sweden)

    Ivana Bolanča Mirković

    2010-01-01

    Full Text Available The awareness of environmental, economic and sociological problems is rising. The purpose of such an approach is to reconcile industrial development with environmental capacities. This approach to environmental protection dates back to the time when the devastation of environment brought on by human factor, the intensification of production process and a build-up of harmful pollutants first became visible. The measures aiming at protecting the environment are a part of the organization system within the production. They are carried out by means of the bat-Best Available Techniques and are based on contemporary technology, which guarantee a high degree of environmental, energetic and economic efficiency.

  19. An approach to control collaborative processes in PLM systems

    CERN Document Server

    Kadiri, Soumaya El; Delattre, Miguel; Bouras, Abdelaziz

    2008-01-01

    Companies that collaborate within the product development processes need to implement an effective management of their collaborative activities. Despite the implementation of a PLM system, the collaborative activities are not efficient as it might be expected. This paper presents an analysis of the problems related to the collaborative work using a PLM system. From this analysis, we propose an approach for improving collaborative processes within a PLM system, based on monitoring indicators. This approach leads to identify and therefore to mitigate the brakes of the collaborative work.

  20. Spreadsheet Assurance by "Control Around" is a Viable Alternative to the Traditional Approach

    CERN Document Server

    Ettema, Harmen; de Swart, Jacques

    2008-01-01

    The traditional approach to spreadsheet auditing generally consists of auditing every distinct formula within a spreadsheet. Although tools are developed to support auditors during this process, the approach is still very time consuming and therefore relatively expensive. As an alternative to the traditional "control through" approach, this paper discusses a "control around" approach. Within the proposed approach not all distinct formulas are audited separately, but the relationship between input data and output data of a spreadsheet is audited through comparison with a shadow model developed in a modelling language. Differences between the two models then imply possible errors in the spreadsheet. This paper describes relevant issues regarding the "control around" approach and the circumstances in which this approach is preferred above a traditional spreadsheet audit approach.

  1. Optimal preview game theory approach to vehicle stability controller design

    Science.gov (United States)

    Tamaddoni, Seyed Hossein; Taheri, Saied; Ahmadian, Mehdi

    2011-12-01

    Dynamic game theory brings together different features that are keys to many situations in control design: optimisation behaviour, the presence of multiple agents/players, enduring consequences of decisions and robustness with respect to variability in the environment, etc. In the presented methodology, vehicle stability is represented by a cooperative dynamic/difference game such that its two agents (players), namely the driver and the direct yaw controller (DYC), are working together to provide more stability to the vehicle system. While the driver provides the steering wheel control, the DYC control algorithm is obtained by the Nash game theory to ensure optimal performance as well as robustness to disturbances. The common two-degrees-of-freedom vehicle-handling performance model is put into discrete form to develop the game equations of motion. To evaluate the developed control algorithm, CarSim with its built-in nonlinear vehicle model along with the Pacejka tire model is used. The control algorithm is evaluated for a lane change manoeuvre, and the optimal set of steering angle and corrective yaw moment is calculated and fed to the test vehicle. Simulation results show that the optimal preview control algorithm can significantly reduce lateral velocity, yaw rate, and roll angle, which all contribute to enhancing vehicle stability.

  2. A Simplified Approach To The Control System On A 4-Axis Curve Generator

    Science.gov (United States)

    Langdon, Wayne R.

    1989-12-01

    The simplest approach in developing a Computerized Numerical Control (CNC) machine tool would be to take a manually-operated machine and fit it with a standard, commercially available computer control system and drive packages, or so it would appear from a machine designer's viewpoint. This approach does tend to minimize the overall machine/system development costs; however, it can result in a control system too sophisticated, overly complex, and more expensive than necessary to control the machine.

  3. Risk and Management Control: A Partial Least Square Modelling Approach

    DEFF Research Database (Denmark)

    Nielsen, Steen; Pontoppidan, Iens Christian

    collected from 72 different types of organizations within different Danish sectors. The results show direct relationships between risk practices and two dimensions; an identify/control dimension and an internal attitude dimension. Also indirect relationships exist between a future expectation dimension...... and a external attitude dimension. The results have important implications for both management control research and for the management control systems design for the way accountants consider the element of risk in their different tasks, both operational and strategic. Specifically, it seems that different risk...

  4. Monitoring Software Reliability using Statistical Process Control: An MMLE Approach

    Directory of Open Access Journals (Sweden)

    Bandla Sreenivasa Rao

    2011-11-01

    Full Text Available This paper consider an MMLE (Modified Maximum Likelihood Estimation based scheme to estimatesoftware reliability using exponential distribution. The MMLE is one of the generalized frameworks ofsoftware reliability models of Non Homogeneous Poisson Processes (NHPPs. The MMLE givesanalytical estimators rather than an iterative approximation to estimate the parameters. In this paper weproposed SPC (Statistical Process Control Charts mechanism to determine the software quality usinginter failure times data. The Control charts can be used to measure whether the software process isstatistically under control or not.

  5. A Network Traffic Control Enhancement Approach over Bluetooth Networks

    DEFF Research Database (Denmark)

    Son, L.T.; Schiøler, Henrik; Madsen, Ole Brun;

    2003-01-01

    This paper analyzes network traffic control issues in Bluetooth data networks as convex optimization problem. We formulate the problem of maximizing of total network flows and minimizing the costs of flows. An adaptive distributed network traffic control scheme is proposed as an approximated...... solution of the stated optimization problem that satisfies quality of service requirements and topologically induced constraints in Bluetooth networks, such as link capacity and node resource limitations. The proposed scheme is decentralized and complies with frequent changes of topology as well...... as capacity limitations and flow requirements in the network. Simulation shows that the performance of Bluetooth networks could be improved by applying the adaptive distributed network traffic control scheme...

  6. CONCEPTUAL APPROACHES TO CREATE CONTROL MECHANISM BY PASSENGER COMMUTATION SERVICES

    Directory of Open Access Journals (Sweden)

    V. O. Zadoya

    2010-11-01

    Full Text Available In the article the basic approaches of improving a management mechanism for passenger suburban railway transportations are considered, and the classification of reformation models for passenger suburban railway transportations depending on scales, degree of independence, department subordination and amount of proprietors of future company is offered.

  7. A Unified Approach to High-Gain Adaptive Controllers

    Directory of Open Access Journals (Sweden)

    Ian A. Gravagne

    2009-01-01

    Full Text Available It has been known for some time that proportional output feedback will stabilize MIMO, minimum-phase, linear time-invariant systems if the feedback gain is sufficiently large. High-gain adaptive controllers achieve stability by automatically driving up the feedback gain monotonically. More recently, it was demonstrated that sample-and-hold implementations of the high-gain adaptive controller also require adaptation of the sampling rate. In this paper, we use recent advances in the mathematical field of dynamic equations on time scales to unify and generalize the discrete and continuous versions of the high-gain adaptive controller. We prove the stability of high-gain adaptive controllers on a wide class of time scales.

  8. Industrial management- control and profit a technical approach

    CERN Document Server

    Halevi, Gideon

    2014-01-01

    This volume presents controlling tools for management in order to be in a position to communicate with control engineers concerning technological decisions. The main objective of manufacturing management is to make profit. However, in traditional manufacturing systems none of the separate stages in the process support this objective. Management is not expert in any of these stages, and therefore is dependent on specific experts at each stage and must follow their decisions. Each stage has its own first priority which is not profit and cost. This means that management does not have real control over these functional stages, nor over the process as a whole. This book presents controlling tools for management in order to allow them to communicate better with the experts of the particular manufacturing stages to reach better results and higher profits. It is shown that most enterprises can improve their efficiency rate by between 25 and 60% by using the tools developed here.

  9. CONTROL OF ANIMAL DISEASES CAUSED BY BACTERIA: PRINCIPLES AND APPROACHES

    Directory of Open Access Journals (Sweden)

    K. Ahmad

    2005-10-01

    Full Text Available To continue to exist, a bacterial pathogen must reproduce and be disseminated among its hosts. Thus, an important aspect of bacterial disease control is a consideration of how reproduction and dissemination of the organism occur. One must identify components of bacterial dissemination that are primarily responsible for a particular disease. Control measures should be directed toward that part of the cycle which is most susceptible to control the weakest links in the chain of disease process. Reducing or eliminating the source or reservoir of infection, breaking the connection between the source of the infection and susceptible animals and reducing the number of susceptible animals by raising the general level of herd immunity with immunization are three main kinds of control measures against bacterial diseases.

  10. Dynamics and Control of Humanoid Robots: A Geometrical Approach

    OpenAIRE

    Ivancevic, Vladimir G.; Ivancevic, Tijana T.

    2011-01-01

    his paper reviews modern geometrical dynamics and control of humanoid robots. This general Lagrangian and Hamiltonian formalism starts with a proper definition of humanoid's configuration manifold, which is a set of all robot's active joint angles. Based on the `covariant force law', the general humanoid's dynamics and control are developed. Autonomous Lagrangian dynamics is formulated on the associated `humanoid velocity phase space', while autonomous Hamiltonian dynamics is formulated on th...

  11. Approaches towards tick and tick-borne diseases control

    OpenAIRE

    Ana Domingos; Sandra Antunes; Lara Borges; Virgilio Estolio do Rosario

    2013-01-01

    Ticks are obligate haematophagous ectoparasites of wild and domestic animals as well as humans, considered to be second worldwide to mosquitoes as vectors of human diseases. Tick-borne diseases are responsible worldwide for great economic losses in terms of mortality and morbidity of livestock animals. This review concerns to the different tick and tick-parasites control methods having a major focus on vaccines. Control of tick infestations has been mainly based on the use of acaricides, a co...

  12. A Goal-Function Approach to Analysis of Control Situations

    DEFF Research Database (Denmark)

    Lind, Morten

    2010-01-01

    The concept of situations plays a central role in all theories of meaning and context. and serve to frame or group events and other occurrences into coherent meaningful wholes. Situations are typed, may be interconnected and organized into higher level structures. In operation of industrial...... to systems modeling like Multilevel Flow Modeling can be used to represent control situations. The paper will describe an action theoretical foundation for MFM and its use for the development of a theory of control situations....

  13. Levels of autonomy control approach for mobile robots

    Science.gov (United States)

    Moorehead, Stewart J.

    2003-09-01

    Increasingly mobile robots are finding applications in the military, mining, nuclear and agriculture industries. These fields require a robot capable of operating in a highly unstructured and changing environment. Current autonomous control techniques are not robust enough to allow successful operation at all times in these environments. Teleoperation can help with many tasks but causes operator fatigue and negates much of the economic advantages of using robots by requiring one person per robot. This paper introduces a control system for mobile robots based on the concept of levels of autonomy. Levels of autonomy recognizes that control can be shared between the operator and robot in a continuous fashion from teleoperation to full autonomy. By sharing control, the robot can benefit from the operator's knowledge of the world to help extricate it from difficult situations. The robot can operate as autonomously as the situation allows, reducing operator fatigue and increasing the economic benefit by allowing a single operator to control multiple robots simultaneously. This paper presents a levels of autonomy control system developed for use in exploration or reconnaissance tasks.

  14. Evaluate fundamental approaches to longwall dust control. Phase III report

    Energy Technology Data Exchange (ETDEWEB)

    Babbitt, C.; Bartlett, P.; Kelly, J.; Ludlow, J.; Mangolds, A.; Rajan, S.; Ruggieri, S.; Varga, E.

    1984-03-31

    The overall objective of the contract is to evaluate the effectiveness of available dust control technology for double-drum shearer longwall sections in a coordinated, systematic program at a few longwall test sections and to make the results available to the entire coal mining industry. This program is investigating nine different dust control techniques. These nine subprograms encompass a broad range of dust control measures ranging from administrative controls to new hardware. They span not only presently employed methods but also those recently adopted in the United States and those proposed for the future. This report documents the Phase III effort on each of the subprograms. For clarity, the report is divided in sections by subprogram as follows: Section 2, Subprogram A - passive barriers/spray air movers for dust control; Section 3, Subprogram B - practical aspects of deep cutting; Section 4, Subprogram C - stage loader dust control; Section 5, Subprogram D - longwall automation technology; Section 6, Subprogram E - longwall application of ventilation curtains; Section 7, Subprogram F - reversed drum rotation; Section 8, Subprogram G - reduction of shield generated dust; Section 9, Subprogram H - air canopies for longwalls; and Section 10, Subprogram I - mining practices. 43 figures, 11 tables.

  15. Comparison of three approaches on DSP based digital controlled 2-wheeler forward converter

    OpenAIRE

    Lau, CK; Pong, MH

    1994-01-01

    This paper presents the design of digital controls of PWM DC-DC converters on a digital signal processor (DSP) based platform. Three digital control approaches are being investigated: discretisation of analog control, digital proportional-integral-derivative (PID) control, and deadbeat control. Simulation results of the three types of control are shown. Experimental results of a 25W 2-wheeler forward converter prototype are presented to verify the design.

  16. Novel reinforcement learning approach for difficult control problems

    Science.gov (United States)

    Becus, Georges A.; Thompson, Edward A.

    1997-09-01

    We review work conducted over the past several years and aimed at developing reinforcement learning architectures for solving difficult control problems and based on and inspired by associative control process (ACP) networks. We briefly review ACP networks able to reproduce many classical instrumental conditioning test results observed in animal research and to engage in real-time, closed-loop, goal-seeking interactions with their environment. Chronologically, our contributions include the ideally interfaced ACP network which is endowed with hierarchical, attention, and failure recognition interface mechanisms which greatly enhanced the capabilities of the original ACP network. When solving the cart-pole problem, it achieves 100 percent reliability and a reduction in training time similar to that of Baird and Klopf's modified ACP network and additionally an order of magnitude reduction in number of failures experienced for successful training. Next we introduced the command and control center/internal drive (Cid) architecture for artificial neural learning systems. It consists of a hierarchy of command and control centers governing motor selection networks. Internal drives, similar hunger, thirst, or reproduction in biological systems, are formed within the controller to facilitate learning. Efficiency, reliability, and adjustability of this architecture were demonstrated on the benchmark cart-pole control problem. A comparison with other artificial learning systems indicates that it learns over 100 times faster than Barto, et al's adaptive search element/adaptive critic element, experiencing less failures by more than an order of magnitude while capable of being fine-tuned by the user, on- line, for improved performance without additional training. Finally we present work in progress on a 'peaks and valleys' scheme which moves away from the one-dimensional learning mechanism currently found in Cid and shows promises in solving even more difficult learning control

  17. An Approach to Autonomous Control for Space Nuclear Power Systems

    Energy Technology Data Exchange (ETDEWEB)

    Wood, Richard Thomas [ORNL; Upadhyaya, Belle R. [University of Tennessee, Knoxville (UTK)

    2011-01-01

    Under Project Prometheus, the National Aeronautics and Space Administration (NASA) investigated deep space missions that would utilize space nuclear power systems (SNPSs) to provide energy for propulsion and spacecraft power. The initial study involved the Jupiter Icy Moons Orbiter (JIMO), which was proposed to conduct in-depth studies of three Jovian moons. Current radioisotope thermoelectric generator (RTG) and solar power systems cannot meet expected mission power demands, which include propulsion, scientific instrument packages, and communications. Historically, RTGs have provided long-lived, highly reliable, low-power-level systems. Solar power systems can provide much greater levels of power, but power density levels decrease dramatically at {approx} 1.5 astronomical units (AU) and beyond. Alternatively, an SNPS can supply high-sustained power for space applications that is both reliable and mass efficient. Terrestrial nuclear reactors employ varying degrees of human control and decision-making for operations and benefit from periodic human interaction for maintenance. In contrast, the control system of an SNPS must be able to provide continuous operatio for the mission duration with limited immediate human interaction and no opportunity for hardware maintenance or sensor calibration. In effect, the SNPS control system must be able to independently operate the power plant while maintaining power production even when subject to off-normal events and component failure. This capability is critical because it will not be possible to rely upon continuous, immediate human interaction for control due to communications delays and periods of planetary occlusion. In addition, uncertainties, rare events, and component degradation combine with the aforementioned inaccessibility and unattended operation to pose unique challenges that an SNPS control system must accommodate. Autonomous control is needed to address these challenges and optimize the reactor control design.

  18. Control of hypertension in the critically ill: a pathophysiological approach.

    Science.gov (United States)

    Salgado, Diamantino Ribeiro; Silva, Eliezer; Vincent, Jean-Louis

    2013-01-01

    Severe acute arterial hypertension can be associated with significant morbidity and mortality. After excluding a reversible etiology, choice of therapeutic intervention should be based on evaluation of a number of factors, such as age, comorbidities, and other ongoing therapies. A rational pathophysiological approach should then be applied that integrates the effects of the drug on blood volume, vascular tone, and other determinants of cardiac output. Vasodilators, calcium channel blockers, and beta-blocking agents can all decrease arterial pressure but by totally different modes of action, which may be appropriate or contraindicated in individual patients. There is no preferred agent for all situations, although some drugs may have a more attractive profile than others, with rapid onset action, short half-life, and fewer adverse reactions. In this review, we focus on the main mechanisms underlying severe hypertension in the critically ill and how using a pathophysiological approach can help the intensivist decide on treatment options. PMID:23806076

  19. Dynamics and control of multibody systems: An approach with application

    Science.gov (United States)

    Grewal, A.; Modi, V. J.

    1996-09-01

    The paper focuses on the study of the dynamics and control of large flexible space structures, comprised of sub-assemblies, a subject of considerable contemporary interest. To begin with, a relatively general Lagrangian formulation of the problem is developed. The governing equations are non-linear, non-autonomous, coupled and extremely lengthy even in matrix notation. Next, an efficient computer code is developed and the versatility of the program illustrated through a study of the dynamics of the First Element Launch (FEL) configuration of the Space Station Freedom, now superseded by the International Space Station Alpha. The response of the FEL is obtained for two critical disturbances: (a) docking of the Space Shuttle; and (b) maneuver of the onboard mobile manipulator system (MSS). The study clearly demonstrates a need for active control. To that end, robust control of the rigid body motion of the FEL configuration using the LQG/LTR procedure is demonstrated. The controller designed using the simplified linear model, proves to be effective in regulating librational disturbances. Such a global approach—formulation, numerical code, dynamics and control—can serve as a powerful tool to gain comprehensive understanding of the interactions of the dynamics and thus aid in the development of effective and efficient control systems.

  20. NeuroControl: system identification approach for clinical benefit.

    Directory of Open Access Journals (Sweden)

    Carel G.M. Meskers

    2015-09-01

    Full Text Available Progress in diagnosis and treatment of movement disorders after neurological diseases like stroke, cerebral palsy, dystonia and at old age requires understanding of the altered capacity to adequately respond to physical obstacles in the environment. With posture and movement disorders, the control of muscles is hampered, resulting in aberrant force generation and improper impedance regulation. Understanding of this improper regulation not only requires the understanding of the role of the neural controller, but also attention for the 1 the interaction between the neural controller and the plant, comprising the biomechanical properties of the skeleton including the viscoelastic properties of the contractile (muscle and non-contractile (connective tissues: neuromechanics and 2 the closed loop nature of neural controller and biomechanical system in which cause and effect interact and are hence difficult to separate. Properties of the neural controller and the biomechanical system need to be addressed synchronously by the combination of haptic robotics, (closed loop system identification, and neuro-mechanical modelling. In this paper, we argue that assessment of neuromechanics in response to well defined environmental conditions and tasks may provide for key parameters to understand posture and movement disorders in neurological diseases and as biomarkers to increase accuracy of prediction models for functional outcome and effects of intervention.

  1. Cognitive control in majority search: A computational modeling approach

    Directory of Open Access Journals (Sweden)

    Hongbin eWang

    2011-02-01

    Full Text Available Despite the importance of cognitive control in many cognitive tasks involving uncertainty, the computational mechanisms of cognitive control in response to uncertainty remain unclear. In this study, we develop biologically realistic neural network models to investigate the instantiation of cognitive control in a majority function task, where one determines the category to which the majority of items in a group belong. Two models are constructed, both of which include the same set of modules representing task-relevant brain functions and share the same model structure. However, with a critical change of a model parameter setting, the two models implement two different underlying algorithms: one for grouping search (where a subgroup of items are sampled and re-sampled until a congruent sample is found and the other for self-terminating search (where the items are scanned and counted one-by-one until the majority is decided. The two algorithms hold distinct implications for the involvement of cognitive control. The modeling results show that while both models are able to perform the task, the grouping search model fit the human data better than the self-terminating search model. An examination of the dynamics underlying model performance reveals how cognitive control might be instantiated in the brain via the V4-ACC-LPFC-IPS loop for computing the majority function.

  2. An approach to control collaborative processes in PLM systems

    OpenAIRE

    Elkadiri, Soumaya; Pernelle, Philippe; Delattre, Miguel; Bouras, Abdelaziz

    2008-01-01

    International audience Companies that collaborate within the product development processes need to implement an effective management of their collaborative activities. Despite the implementation of a PLM system, the collaborative activities are not efficient as it might be expected. This paper presents an analysis of the problems related to the collaborative work using a PLM system. From this analysis, we propose an approach for improving collaborative processes within a PLM system, based ...

  3. Optimal step-down approach for pediatric asthma controlled by salmeterol/fluticasone: A randomized, controlled trial (OSCAR study

    Directory of Open Access Journals (Sweden)

    Kenichi Akashi

    2016-07-01

    Conclusions: A high level of asthma control was maintained with both approaches. The use of SFC step-down resulted in somewhat better respiratory function, with no worsening of airway inflammation. However, halving the dose of SFC and switching to FP alone are both optimal step-down approaches.

  4. Action-Amplitude Approach to Controlled Entropic Self-Organization

    Directory of Open Access Journals (Sweden)

    Vladimir Ivancevic

    2014-05-01

    Full Text Available Motivated by the notion of perceptual error, as a core concept of the perceptual control theory, we propose an action-amplitude model for controlled entropic self-organization (CESO. We present several aspects of this development that illustrate its explanatory power: (i a physical view of partition functions and path integrals, as well as entropy and phase transitions; (ii a global view of functional compositions and commutative diagrams; (iii a local geometric view of the Kähler–Ricci flow and time-evolution of entropic action; and (iv a computational view using various path-integral approximations.

  5. Game Theoretic Approach to Post-Docked Satellite Control

    Science.gov (United States)

    Hiramatsu, Takashi; Fitz-Coy, Norman G.

    2007-01-01

    This paper studies the interaction between two satellites after docking. In order to maintain the docked state with uncertainty in the motion of the target vehicle, a game theoretic controller with Stackelberg strategy to minimize the interaction between the satellites is considered. The small perturbation approximation leads to LQ differential game scheme, which is validated to address the docking interactions between a service vehicle and a target vehicle. The open-loop solution are compared with Nash strategy, and it is shown that less control efforts are obtained with Stackelberg strategy.

  6. The magic ring systems thinking approach to control systems

    CERN Document Server

    Mella, Piero

    2014-01-01

    This book presents a gradual path toward ""educating"" readers in understanding how Control Systems truly operate and in recognizing, simulating and improving them in all fields of activity. Starting from the hypothesis that knowledge of Control Systems is not only a technical fact but also represents a discipline - that is, ""A discipline is a developmental path for acquiring certain skills or competencies. (...) To practice a discipline is to be a lifelong learner. You ""never arrive""; you spend your life mastering disciplines."" (Senge, 2006, p. 10) - Piero Mella has set the objective of m

  7. Access Control for Agent-based Computing: A Distributed Approach.

    Science.gov (United States)

    Antonopoulos, Nick; Koukoumpetsos, Kyriakos; Shafarenko, Alex

    2001-01-01

    Discusses the mobile software agent paradigm that provides a foundation for the development of high performance distributed applications and presents a simple, distributed access control architecture based on the concept of distributed, active authorization entities (lock cells), any combination of which can be referenced by an agent to provide…

  8. Accounting Control Technology Using SAP: A Case-Based Approach

    Science.gov (United States)

    Ragan, Joseph; Puccio, Christopher; Talisesky, Brandon

    2014-01-01

    The Sarbanes-Oxley Act (SOX) revolutionized the accounting and audit industry. The use of preventative and process controls to evaluate the continuous audit process done via an SAP ERP ECC 6.0 system is key to compliance with SOX and managing costs. This paper can be used in a variety of ways to discuss issues associated with auditing and testing…

  9. Formation control of marine surface craft: a Lagrangian approach

    DEFF Research Database (Denmark)

    Ihle, Ivar-Andre F.; Jouffroy, Jerome; Fossen, Thor I.

    2006-01-01

    This paper presents a method for formation control of marine surface craft inspired by Lagrangian mechanics. The desired formation configuration and response of the marine surface craft are given as a set of constraints in analytical mechanics. Thus, constraints forces arise and feedback from...

  10. A user experience-based approach to home atmosphere control

    NARCIS (Netherlands)

    Vastenburg, M.H.; Ross, P.R.; Keyson, D.V.

    2007-01-01

    The complex control problem of creating home atmospheres using light, music, and projected wall-art can be reduced by focusing on desired expe- rience, rather than product functions and features. A case study is described in which subjective interpreta- tions of living room atmospheres were measured

  11. Detecting Approaching Vehicles at Streets with No Traffic Control

    Science.gov (United States)

    Emerson, Robert Wall; Sauerburger, Dona

    2008-01-01

    This study assessed the ability of people with visual impairments to reliably detect oncoming traffic at crossing situations with no traffic control. In at least one condition, the participants could not hear vehicles to afford a safe crossing time when sound levels were as quiet as possible. Significant predictors of detection accounted for a…

  12. AN INTERDISCIPLINARY APPROACH TO VALUING WATER FROM BRUSH CONTROL

    Science.gov (United States)

    An analytical methodology utilizing models from three disciplines is developed to assess the viability of brush control for wate yield in the Frio River Basin, TX. Ecological, hydrologic, and economic models are used to portray changes in forage production and water supply result...

  13. Supervisor localization a top-down approach to distributed control of discrete-event systems

    CERN Document Server

    Cai, Kai

    2016-01-01

    This monograph presents a systematic top-down approach to distributed control synthesis of discrete-event systems (DES). The approach is called supervisor localization; its essence is the allocation of external supervisory control action to individual component agents as their internal control strategies. The procedure is: first synthesize a monolithic supervisor, to achieve globally optimal and nonblocking controlled behavior, then decompose the monolithic supervisor into local controllers, one for each agent. The collective behavior of the resulting local controllers is identical to that achieved by the monolithic supervisor. The basic localization theory is first presented in the Ramadge–Wonham language-based supervisory control framework, then demonstrated with distributed control examples of multi-robot formations, manufacturing systems, and distributed algorithms. An architectural approach is adopted to apply localization to large-scale DES; this yields a heterarchical localization procedure, which is...

  14. Control system of motivation of personal based on gradient approach

    Directory of Open Access Journals (Sweden)

    Doliatovskii Valerii Anastasievich

    2014-07-01

    Full Text Available The concept of management by motivation of workers on the basis of definition of sensitivity of results of work to influence various motives is proved. There by the object of management is identified by a set of indicators of sensitivity which are the limiting sizes defining reaction of workers on motives. By averaging of the given questionnaires the matrix of identification of system of motivation is received. On its basis the decision of direct and return problems of management is possible. Experimental data about results of application are led to a choice of system of motivation based on gradient the approach.

  15. Project management a systems approach to planning, scheduling, and controlling

    CERN Document Server

    Kerzner, Harold R

    2013-01-01

    The bestselling project management text for students and professionals-now updated and expanded This Eleventh Edition of the bestselling ""bible"" of project management maintains the streamlined approach of the prior editions and moves the content even closer to PMI''s Project Management Body of Knowledge (PMBOK). New content has been added to this edition on measuring project management ROI, value to the organization and to customers, and much more. The capstone ""super"" case on the ""Iridium Project"" has been maintained, covering all aspects of project management. Increased use of sideba

  16. Refractory asthma - An old disorder: Novel approaches for effective control.

    Science.gov (United States)

    Prasad, B N B M

    2016-07-01

    Bronchial asthma is an inflammatory disorder of airways characterized by hyper-responsiveness to a wide range of triggers and is associated with variable airflow obstruction that remits spontaneously or with the treatment. Several phenotype of asthma not responding to the currently acceptable standard therapy of high dose inhaled gluco-corticosteroids along with along acting β2 agonists come under the purview of refractory asthma. This condition is a heterogeneous and complex disease that requires a multi-disciplinary approach to identify accurately various sub-phenotypes to enable improved understanding of the pathogenesis and development of effective management strategies including use of novel methods and targeted therapy. PMID:27546969

  17. A market approach to decentralized control of a manufacturing cell

    International Nuclear Information System (INIS)

    Based on a fictitious market model, a decentralized approach is presented for the workstation scheduling in a CNC workshop. A multi-agent framework is proposed, where job agents and resource agents act as buyers and sellers of resource in the virtual market. With cost and benefit calculation of these agent activities, which reflects the state of the production environment, various, and often conflicting goals and interests influencing the scheduling process in practice can be balanced through a unified instrument offered by the markets. The paper first introduces a heuristic procedure that makes scheduling reservations in a periodic manner. A multi-agent framework is then introduced, in which job agents and resource agents seek appropriate job-workstation matches through bidding in the construction of the above periodic 'micro-schedules'. A pricing policy is proposed for the price-directed coordination of agent activities in this. Simulation results demonstrate the feasibility of the proposed approach and give some insights on the effects of some decision making parameters. Future work will be focused on the designing of some more sophisticated coordination mechanism and its deployment.

  18. Two Approaches to Control of Fed-batch Fermentation Process

    Directory of Open Access Journals (Sweden)

    Tatiana Ilkova

    2008-10-01

    Full Text Available L-lysine is one of the irreplaceable aminoacids whose content in the animal protein is relatively high in comparison to plants, where the content is relatively low. The insufficiently L-lysine quantity in the fodders reduces the biological value of the fodder doses, reduces the weight increase and the further productiveness of the agricultural animals, it increases the fodder quantity, used for a kilogram growth and decreases the product quantity of animal origin. The most effective and cheapest method for the L-lysine biosynthesis (in biological active form is the microbiological method via a direct fermentation. In this paper it is used an optimization method at the L-lysine production from strain Brevibacterium flavum 22LD - Neuro-dynamic programming. For receiving a feedback and robustness of the optimal control profile the Model predictive control of the L-lysine production is developed.

  19. Gravity Control Propulsion: Towards a General Relativistic Approach

    OpenAIRE

    Bertolami, O.; Pedro, F. G.

    2006-01-01

    Evaluation of gravity control concepts should be examined with respect to currently known physical theories. In this work we study the hypothetical conversion of gravitational potential energy into kinetic energy using the formalism of general relativity. We show that the energy involved in the process greatly exceeds the Newtonian estimate, given the nature of general relativity. We conclude that the impact of any gravity manipulation for propulsion greatly depends fundamentally on its exact...

  20. AMAZON RAINFOREST COSMETICS: CHEMICAL APPROACH FOR QUALITY CONTROL

    OpenAIRE

    Mariko Funasaki; Hileia dos Santos Barroso; Valdelira Lia Araújo Fernandes; Ingrid Sabino Menezes

    2016-01-01

    The market for natural cosmetics featuring ingredients derived from Amazon natural resources is growing worldwide. However, there is neither enough scientific basis nor quality control of these ingredients. This paper is an account of the chemical constituents and their biological activities of fourteen Amazonian species used in cosmetic industry, including açaí (Euterpe oleracea), andiroba (Carapa guianensis), bacuri (Platonia insignis), Brazil nut (Bertholletia excelsa), buriti (Mauritia vi...

  1. New approaches to pain control in patients with cancer.

    Science.gov (United States)

    Ahmedzai, S

    1997-07-01

    Pain affects most patients with malignant disease, and the prevalence of severe pain increases in the advanced stages of the condition. One in 5 patients with cancer has uncontrolled pain, even after 10 years of the use of the World Health Organization programme for cancer pain control and its 'three-step ladder' for the rational use of analgesics including morphine. Morphine has long been the 'gold standard' for the treatment of severe cancer pain. However, its side-effects, particularly sedation, cognitive impairment and myoclonus at high doses, have provoked the use of 'opioid rotation' to alternatives such as methadone and hydromorphone. The new 72-h transdermal patch for fentanyl also offers advantages of reduced side-effects and increased convenience over oral morphine. Intravenous strontium-89 and bisphosphonate therapy are effective for both short- and long-term control of metastatic bone pain. The spinal N-methyl-D-aspartate (NMDA) receptor is important in modulating the plasticity of the central nervous system and in aggravating chronic pain through the phenomenon of 'wind-up'. The NMDA antagonist ketamine, an anaesthetic, can be used at low doses for the management of refractory and neuropathic pains. Among adjuvant drugs, ketorolac has emerged as a potent non-steroidal anti-inflammatory drug. Palliative care is gaining acceptance as a new discipline in healthcare. Its strategic role is being reviewed as an adjunct to cancer therapy at all stages and its use is no longer confined to the terminal phase of disease after curative treatment has failed. Pain control and other aspects of symptom control are, therefore, viewed as an integral part of cancer management.

  2. An AI-Based Approach to Destination Control in Elevators

    OpenAIRE

    Koehler, Jana; Ottiger, Daniel

    2002-01-01

    Not widely known by the AI community, elevator control has become a major field of application for AI technologies. Techniques such as neural networks, genetic algorithms, fuzzy rules and, recently, multiagent systems and AI planning have been adopted by leading elevator companies not only to improve the transportation capacity of conventional elevator systems but also to revolutionize the way in which elevators interact with and serve passengers. In this article, we begin with an overview of...

  3. Technical enforcement of european privacy legislation: an access control approach

    OpenAIRE

    Bekara, Kheira; Laurent, Maryline; Nguyen, Than Ha

    2012-01-01

    Until today, the protection of personal data is mainly left to the legislation by means of guidelines. This paper aims to increase the perceived control by users over their data by helping the user's agent to check the service requests conformity to the legislation. To do so, it discusses the main concepts involved in the legislative privacy principles, and deduces a privacy semantic information model. The proposed model focuses on the main concepts involved in legislative privacy principles....

  4. Approaches towards tick and tick-borne diseases control

    Directory of Open Access Journals (Sweden)

    Ana Domingos

    2013-04-01

    Full Text Available Ticks are obligate haematophagous ectoparasites of wild and domestic animals as well as humans, considered to be second worldwide to mosquitoes as vectors of human diseases. Tick-borne diseases are responsible worldwide for great economic losses in terms of mortality and morbidity of livestock animals. This review concerns to the different tick and tick-parasites control methods having a major focus on vaccines. Control of tick infestations has been mainly based on the use of acaricides, a control measure with serious drawbacks, as responsible for the contamination of milk and meat products, as a selective factor for acaricide-resistant ticks and as an environmental contaminant. Research on alternatives to the use of acaricides is strongly represented by tick vaccines considered a more cost-effective and environmentally safe strategy. Vaccines based on the Bm86 tick antigen were used in the first commercially available cattle tick vaccines and showed good results in reducing tick numbers, affecting weight and reproductive performance of female ticks which resulted in reduction of cattle tick populations over time and consequently lower reduction of the pathogen agents they carry.

  5. Approaches towards tick and tick-borne diseases control.

    Science.gov (United States)

    Domingos, Ana; Antunes, Sandra; Borges, Lara; Rosário, Virgílio Estólio do

    2013-01-01

    Ticks are obligate haematophagous ectoparasites of wild and domestic animals as well as humans, considered to be second worldwide to mosquitoes as vectors of human diseases. Tick-borne diseases are responsible worldwide for great economic losses in terms of mortality and morbidity of livestock animals. This review concerns to the different tick and tick-parasites control methods having a major focus on vaccines. Control of tick infestations has been mainly based on the use of acaricides, a control measure with serious drawbacks, as responsible for the contamination of milk and meat products, as a selective factor for acaricide-resistant ticks and as an environmental contaminant. Research on alternatives to the use of acaricides is strongly represented by tick vaccines considered a more cost-effective and environmentally safe strategy. Vaccines based on the Bm86 tick antigen were used in the fi rst commercially available cattle tick vaccines and showed good results in reducing tick numbers, affecting weight and reproductive performance of female ticks which resulted in reduction of cattle tick populations over time and consequently lower reduction of the pathogen agents they carry. PMID:23559344

  6. Light-Duty Vehicle Exhaust Emission Control Cost Estimates Using a Part-Pricing Approach

    OpenAIRE

    Wang, Quanlu; Kling, Catherine; Sperling, Daniel

    1993-01-01

    The substantial reductions in motor vehicle emissions that have occurred since the late 1960s have been accompanied by continuous increases in vehicle emission control costs, and cost increases or decreases due to changes in vehicle performance such as driveability, power, fuel economy, and vehicle maintenance. In this paper, a systematic approach has been developed to estimate emission control costs for motor vehicles. The approach accounts for all emission control parts installed on vehicle...

  7. Acceptability of impregnated school uniforms for dengue control in Thailand: a mixed methods approach

    OpenAIRE

    Murray, Natasha; Jansarikij, Suphachai; Olanratmanee, Phanthip; Maskhao, Pongsri; Souares, Aurélia; Wilder-Smith, Annelies; Kittayapong, Pattamaporn; Louis, Valérie R

    2014-01-01

    Background: As current dengue control strategies have been shown to be largely ineffective in reducing dengue in school-aged children, novel approaches towards dengue control need to be studied. Insecticide-impregnated school uniforms represent an innovative approach with the theoretical potential to reduce dengue infections in school children.Objectives: This study took place in the context of a randomised control trial (RCT) to test the effectiveness of permethrin-impregnated school uniform...

  8. Exponential Tracking Control Using Backstepping Approach for Voltage-Based Control of a Flexible Joint Electrically Driven Robot

    Directory of Open Access Journals (Sweden)

    Jean Bosco Mbede

    2014-01-01

    Full Text Available This paper addresses the design of exponential tracking control using backstepping approach for voltage-based control of a flexible joint electrically driven robot (EFJR, to cope with the difficulty introduced by the cascade structure in EFJR dynamic model, to deal with flexibility in joints, and to ensure fast tracking performance. Backstepping approach is used to ensure global asymptotic stability and its common algorithm is modified such that the link position and velocity errors converge to zero exponentially fast. In contrast with the other backstepping controller for electrically driven flexible joint robot manipulators control problem, the proposed controller is robust with respect to stiffness uncertainty and allows tracking fast motions. Simulation results are presented for both single link flexible joint electrically driven manipulator and 2-DOF flexible joint electrically driven robot manipulator. These simulations show very satisfactory tracking performances and the superiority of the proposed controller to those performed in the literature using simple backstepping methodology.

  9. Multicontroller: an object programming approach to introduce advanced control algorithms for the GCS large scale project

    CERN Document Server

    Cabaret, S; Coppier, H; Rachid, A; Barillère, R; CERN. Geneva. IT Department

    2007-01-01

    The GCS (Gas Control System) project team at CERN uses a Model Driven Approach with a Framework - UNICOS (UNified Industrial COntrol System) - based on PLC (Programming Language Controller) and SCADA (Supervisory Control And Data Acquisition) technologies. The first' UNICOS versions were able to provide a PID (Proportional Integrative Derivative) controller whereas the Gas Systems required more advanced control strategies. The MultiController is a new UNICOS object which provides the following advanced control algorithms: Smith Predictor, PFC (Predictive Function Control), RST* and GPC (Global Predictive Control). Its design is based on a monolithic entity with a global structure definition which is able to capture the desired set of parameters of any specific control algorithm supported by the object. The SCADA system -- PVSS - supervises the MultiController operation. The PVSS interface provides users with supervision faceplate, in particular it links any MultiController with recipes: the GCS experts are ab...

  10. Ecological approaches to oral biofilms: control without killing.

    Science.gov (United States)

    Marsh, Phil D; Head, David A; Devine, Deirdre A

    2015-01-01

    Humans have co-evolved with micro-organisms and have a symbiotic or mutualistic relationship with their resident microbiome. As at other body surfaces, the mouth has a diverse microbiota that grows on oral surfaces as structurally and functionally organised biofilms. The oral microbiota is natural and provides important benefits to the host, including immunological priming, down-regulation of excessive pro-inflammatory responses, regulation of gastrointestinal and cardiovascular systems, and colonisation by exogenous microbes. On occasions, this symbiotic relationship breaks down, and previously minor components of the microbiota outcompete beneficial bacteria, thereby increasing the risk of disease. Antimicrobial agents have been formulated into many oral care products to augment mechanical plaque control. A delicate balance is needed, however, to control the oral microbiota at levels compatible with health, without killing beneficial bacteria and losing the key benefits delivered by these resident microbes. These antimicrobial agents may achieve this by virtue of their recommended twice daily topical use, which results in pharmacokinetic profiles indicating that they are retained in the mouth for relatively long periods at sublethal levels. At these concentrations they are still able to inhibit bacterial traits implicated in disease (e.g. sugar transport/acid production; protease activity) and retard growth without eliminating beneficial species. In silico modelling studies have been performed which support the concept that either reducing the frequency of acid challenge and/or the terminal pH, or by merely slowing bacterial growth, results in maintaining a community of beneficial bacteria under conditions that might otherwise lead to disease (control without killing).

  11. Physiological approaches to the control of oral biofilms.

    Science.gov (United States)

    Marsh, P D; Bradshaw, D J

    1997-04-01

    Evidence that physiological strategies may be potential routes for oral biofilm control has come from (i) observations of the variations in the intra-oral distribution of members of the resident oral microflora, (ii) changes in plaque composition in health and disease, and (iii) data from laboratory model systems. Key physiological factors that were identified as significant in modulating the microflora included the local pH, redox potential (Eh), and nutrient availability. Increases in mutans streptococci and lactobacilli occur at sites with caries; growth of these species is selectively enhanced at low pH. In contrast, periodontal diseases are associated with plaque accumulation, followed by an inflammatory host response. The increases in Gram-negative, proteolytic, and obligately anaerobic bacteria reflect a low redox potential and a change in nutrient status due to the increased flow of gingival crevicular fluid (GCF). Consequently, physiological strategies for oral biofilm control should focus on reducing the frequency of low pH in plaque by (i) inhibiting acid production, (ii) using sugar substitutes, and (iii) promoting alkali generation from arginine or urea supplements. Similarly, strategies to make the pocket environment less favorable to periodonto-pathogens include (i) anti-inflammatory agents to reduce the flow of (and hence nutrient supply by) GCF, (ii) bacterial protease inhibitors, and (iii) redox agents to raise the Eh locally. Most laboratory and clinical findings support the concept of physiological control. However, some data suggest that the ordered structure and metabolically interactive organization of mature dental plaque could generate a community with a high level of homeostasis that is relatively resistant to deliberate external manipulation.

  12. Control design approaches for nonlinear systems using multiple models

    Institute of Scientific and Technical Information of China (English)

    Junyong ZHAI; Shumin FEI; Feipeng DA

    2007-01-01

    It is difficult to realize control for some complex nonlinear systems operated in different operating regions.Based on developing local models for different operating regions of the process, a novel algorithm using multiple models is proposed. It utilizes dynamic model bank to establish multiple local models, and their membership functions are defined according to respective regions. Then the nonlinear system is approximated to a weighted combination of the local models.The stability of the nonlinear system is proven. Finally, simulations are given to demonstrate the validity of the proposed method.

  13. Spatial operator approach to flexible multibody system dynamics and control

    Science.gov (United States)

    Rodriguez, G.

    1991-01-01

    The inverse and forward dynamics problems for flexible multibody systems were solved using the techniques of spatially recursive Kalman filtering and smoothing. These algorithms are easily developed using a set of identities associated with mass matrix factorization and inversion. These identities are easily derived using the spatial operator algebra developed by the author. Current work is aimed at computational experiments with the described algorithms and at modelling for control design of limber manipulator systems. It is also aimed at handling and manipulation of flexible objects.

  14. A Memory/Immunology-Based Control Approach with Applications to Multiple Spacecraft Formation Flying

    Directory of Open Access Journals (Sweden)

    Liguo Weng

    2013-01-01

    Full Text Available This paper addresses the problem of formation control for multiple spacecrafts in Planetary Orbital Environment (POE. Due to the presence of diverse interferences and uncertainties in the outer space, such as the changing spacecraft mass, unavailable space parameters, and varying gravity forces, traditional control methods encounter great difficulties in this area. A new control approach inspired by human memory and immune system is proposed, and this approach is shown to be capable of learning from past control experience and current behavior to improve its performance. It demands much less system dynamic information as compared with traditional controls. Both theoretic analysis and computer simulation verify its effectiveness.

  15. A systematic approach to control of radioactive waste discharges

    International Nuclear Information System (INIS)

    The setting of controls of radioactive waste discharges from the major nuclear sites in England is a statutory responsibility of the Minister of Agriculture, Fisheries and Food acting jointly with the Chief Inspector of Her Majesty's Inspectorate of Pollution, within the terms of the Radioactive Substances Act 1960 as amended by the Environmental Protection Act 1990. MAFF's technical responsibilities are divided between the Food Safety (Radiation) Unit, which is responsible for terrestrial exposure pathways, and the Fisheries Radiological Inspectorate, responsible for aquatic exposure pathways. Both groups operate in a similar way and their work can be considered to fall into four main areas. First, discharge routes, important isotopes, exposure pathways and doses to the public are considered. Second, the adequacy of discharge controls is monitored by inspection of plant operations and site records, and by MAFF's supervision of an environmental monitoring programme by the polluter. Third, an independent 'check' monitoring programme is carried out on the environmental impact. Fourth, there is a complementary research programme involving specific projects designed to support monitoring and assessments methodology. (author)

  16. Procurement control - A proactive approach to seller management

    International Nuclear Information System (INIS)

    The successful completion of any program is directly and intimately related to the seller's ability to make satisfactory progress in achieving the program's objectives. Impairments to progress include but are not limited to (a) evolving or pacing technology development, (b) production and manufacturing problems, (c) seller's subcontractor difficulties, (d) seller cash flow, and (e) buyer/seller contractual or relationship issues. While it is not possible to anticipate every problem that can occur during program performance, their occurrence and effect can be minimized by preaward and postaward attention by the buyer. But who is responsible? The engineer, concerned with achieving the technical objectives of the program, is not interested in the management of the acquisition or the contract administrative details. The contract administrator often lacks the technical skills and insights necessary to head off and resolve production problems. A procurement control organization, involved at the initial stage of acquisition strategy development and dedicated to procurement control, will have a pronounced effect on the successful completion of the program and attainment of its objectives

  17. Production of viable cultures of Flavobacterium psychrophilum: approach and control.

    Science.gov (United States)

    Michel, C; Antonio, D; Hedrick, R P

    1999-06-01

    Although the fish pathogen Flavobacterium psychrophilum is a major source of concern in salmonid hatcheries, few studies have been conducted on its pathogenicity. Difficulties are often experienced when trying to control or quantify standard procedures for in vitro culture of the bacterium. Plate enumeration and counting chamber enumeration combined with epifluorescent microscopy with fluorescent dyes determined that no more than 25% of the bacterial cells present in the cultures were able to produce colonies on agar media. This was strongly dependent upon different medium components. Tryptone-enriched Anacker and Ordal medium proved more suitable than tryptone-yeast extract-salts with skimmed milk. Adding horse serum and trace elements in controlled proportions offered the most reproducible results. Viable but nonculturable forms were apparently not responsible for the difficulties in production of F. psychrophilum, but the cells were highly susceptible to osmotic conditions. Improvements in the media and careful handling of the bacteria in isotonic suspension media resulted in predictable production of viable bacteria and allowed an absorbance/colony-forming-units relation curve to be established.

  18. A transgenic approach for controlling Lygus in cotton.

    Science.gov (United States)

    Gowda, Anilkumar; Rydel, Timothy J; Wollacott, Andrew M; Brown, Robert S; Akbar, Waseem; Clark, Thomas L; Flasinski, Stanislaw; Nageotte, Jeffrey R; Read, Andrew C; Shi, Xiaohong; Werner, Brent J; Pleau, Michael J; Baum, James A

    2016-01-01

    Lygus species of plant-feeding insects have emerged as economically important pests of cotton in the United States. These species are not controlled by commercial Bacillus thuringiensis (Bt) cotton varieties resulting in economic losses and increased application of insecticide. Previously, a Bt crystal protein (Cry51Aa2) was reported with insecticidal activity against Lygus spp. However, transgenic cotton plants expressing this protein did not exhibit effective protection from Lygus feeding damage. Here we employ various optimization strategies, informed in part by protein crystallography and modelling, to identify limited amino-acid substitutions in Cry51Aa2 that increase insecticidal activity towards Lygus spp. by >200-fold. Transgenic cotton expressing the variant protein, Cry51Aa2.834_16, reduce populations of Lygus spp. up to 30-fold in whole-plant caged field trials. One transgenic event, designated MON88702, has been selected for further development of cotton varieties that could potentially reduce or eliminate insecticide application for control of Lygus and the associated environmental impacts. PMID:27426014

  19. A New Approach to an Automated Air Traffic Control

    Institute of Scientific and Technical Information of China (English)

    Patchev Dragoljub

    2014-01-01

    This paper identifies areas of improvements of the air traffic control system and proposes modification of the concept of automation by using available technologies. With the proposed modification, the current Europe wide en route network structure can be modified in order to make routes more optimal. For this new route network structure, a new concept of automation will be used to manage with the air traffic. The first identified area of improvement is implementation of automation process that will enable decentralization of the air traffic control functionality to each individual aircraft and this will be achieved through automated routing of the aircrafts and CD&R (conflict detection and resolution). The FMS (flight management system) at the aircraft will make decisions for the optimal flight route based on the sensor inputs, information on selection of the routes, next hope points and flight levels, all received by ADS-B (automatic dependant surveillance-broadcast). The second area is processing the information about the deviation from the optimal route as in flight plan due to a traffic management (vectoring, level change) and taking it into consideration when further actions are undertaken. For each action, a cost factor will be calculated from the fuel burned for that action. This factor will be used to select conflict resolution protocol. The proposed concept shall increase the capacity of the network, and enable the air traff~c more efficient and more environmentally friendly while maintaining safe separation.

  20. Supramolecular Approaches to Nanoscale Morphological Control in Organic Solar Cells

    Directory of Open Access Journals (Sweden)

    Alexander M. Haruk

    2015-06-01

    Full Text Available Having recently surpassed 10% efficiency, solar cells based on organic molecules are poised to become a viable low-cost clean energy source with the added advantages of mechanical flexibility and light weight. The best-performing organic solar cells rely on a nanostructured active layer morphology consisting of a complex organization of electron donating and electron accepting molecules. Although much progress has been made in designing new donor and acceptor molecules, rational control over active layer morphology remains a central challenge. Long-term device stability is another important consideration that needs to be addressed. This review highlights supramolecular strategies for generating highly stable nanostructured organic photovoltaic active materials by design.

  1. A Novel Agent Based Approach for Controlling Network Storms

    CERN Document Server

    Nair, Dr T R Gopalakrishnan; M, Vaidehi

    2011-01-01

    One of the fundamental data transmission mechanisms in Ethernet LAN is broadcasting. Flooding is a direct broadcasting technique used in these networks. A significant drawback of this method is that it can lead to broadcast storms. This phenomenon is more common in multivendor switch environment. Broadcast storms usually results in dissension, collision and redundancy leading to degradation of the network performance. Most of the storms appear without much warning and it affects the efficiency of network even in situations when the network is expected to work most efficiently. There are several characteristic patterns by which storm can appear in a LAN, like rate monotonic repetition, transient appearances with different types of growth properties and decay profiles. In this paper we discuss the storm build up pattern in an industry and present various reasons for storm in LAN. We have identified a strategy for controlling network storms, using multiple static agents. These agents inhibit storm packet regener...

  2. An Algebraic Approach for the MIMO Control of Small Scale Helicopter

    CERN Document Server

    Budiyono, A

    2008-01-01

    The control of small-scale helicopter is a MIMO problem. To use of classical control approach to formally solve a MIMO problem, one needs to come up with multidimensional Root Locus diagram to tune the control parameters. The problem with the required dimension of the RL diagram for MIMO design has forced the design procedure of classical approach to be conducted in cascaded multi-loop SISO system starting from the innermost loop outward. To implement this control approach for a helicopter, a pitch and roll attitude control system is often subordinated to a, respectively, longitudinal and lateral velocity control system in a nested architecture. The requirement for this technique to work is that the inner attitude control loop must have a higher bandwidth than the outer velocity control loop which is not the case for high performance mini helicopter. To address the above problems, an algebraic design approach is proposed in this work. The designed control using s-CDM approach is demonstrated for hovering cont...

  3. LQG Control Approach to Gaussian Broadcast Channels with Feedback

    CERN Document Server

    Ardestanizadeh, Ehsan; Franceschetti, Massimo

    2011-01-01

    A code for communication over the k-receiver additive white Gaussian noise broadcast channel with feedback is presented and analyzed using tools from the theory of linear quadratic Gaussian optimal control. It is shown that the performance of this code depends on the noise correlation at the receivers and it is related to the solution of a discrete algebraic Riccati equation. For the case of independent noises, the sum rate achieved by the proposed code, satisfying average power constraint P, is characterized as 1/2 log (1+P*phi), where the coefficient "phi" in the interval [1,k] quantifies the power gain due to the presence of feedback. When specialized to the case of two receivers, this includes a previous result by Elia and strictly improves upon the code of Ozarow and Leung. When the noises are correlated, the pre-log of the sum-capacity of the broadcast channel with feedback can be strictly greater than one. It is established that for all noise covariance matrices of rank r the pre-log of the sum capacit...

  4. A neuroeconomics approach to inferring utility functions in sensorimotor control.

    Directory of Open Access Journals (Sweden)

    Konrad P Körding

    2004-10-01

    Full Text Available Making choices is a fundamental aspect of human life. For over a century experimental economists have characterized the decisions people make based on the concept of a utility function. This function increases with increasing desirability of the outcome, and people are assumed to make decisions so as to maximize utility. When utility depends on several variables, indifference curves arise that represent outcomes with identical utility that are therefore equally desirable. Whereas in economics utility is studied in terms of goods and services, the sensorimotor system may also have utility functions defining the desirability of various outcomes. Here, we investigate the indifference curves when subjects experience forces of varying magnitude and duration. Using a two-alternative forced-choice paradigm, in which subjects chose between different magnitude-duration profiles, we inferred the indifference curves and the utility function. Such a utility function defines, for example, whether subjects prefer to lift a 4-kg weight for 30 s or a 1-kg weight for a minute. The measured utility function depends nonlinearly on the force magnitude and duration and was remarkably conserved across subjects. This suggests that the utility function, a central concept in economics, may be applicable to the study of sensorimotor control.

  5. When Spreadsheets Become Software - Quality Control Challenges and Approaches - 13360

    International Nuclear Information System (INIS)

    As part of a preliminary waste acceptance criteria (PWAC) development, several commercial models were employed, including the Hydrologic Evaluation of Landfill Performance model (HELP) [1], the Disposal Unit Source Term - Multiple Species model (DUSTMS) [2], and the Analytical Transient One, Two, and Three-Dimensional model (AT123D) [3]. The results of these models were post-processed in MS Excel spreadsheets to convert the model results to alternate units, compare the groundwater concentrations to the groundwater concentration thresholds, and then to adjust the waste contaminant masses (based on average concentration over the waste volume) as needed in an attempt to achieve groundwater concentrations at the limiting point of assessment that would meet the compliance concentrations while maximizing the potential use of the landfill (i.e., maximizing the volume of projected waste being generated that could be placed in the landfill). During the course of the PWAC calculation development, one of the Microsoft (MS) Excel spreadsheets used to post-process the results of the commercial model packages grew to include more than 575,000 formulas across 18 worksheets. This spreadsheet was used to assess six base scenarios as well as nine uncertainty/sensitivity scenarios. The complexity of the spreadsheet resulted in the need for a rigorous quality control (QC) procedure to verify data entry and confirm the accuracy of formulas. (authors)

  6. Integrated analytical approaches for food traceability and pollution control

    International Nuclear Information System (INIS)

    It developed in the laboratory of Food Science of the Montevideo commissariat a regional workshop with the following aims:To evaluate the effect of vegetable matrices on the determination of pesticides through analysis by GC / M S. For the implementation and application of these tests, it was applied the Laboratory s protocol which it was distributed to all members of the working group. It worked with a matrix lettuce, chard and a mix of green leafy vegetables , evaluating the matrix effect in the following pesticides: chloropyrifos, procimidione, L-cyhalothrin, azoxystrobin, trifluralin and fenbuconazole, using heptachlor as internal standard.They carried out in five concentration levels, in triplicate tests, applying the techniques of extraction by QuEChERS (kit agile nt). Prepared samples are injected into the GC / M S equipment, an analysis of the results were evaluated by the working group. Furthermore this regional workshop was about nuclear techniques role in agricultural practice, the traceability and pollution control, laboratory services and farmers relationships, environmental, economic, social and political impact, pest prevention and animal diseases, risk, the human health, environment protection in the agricultural and the pesticides uses.

  7. Hybrid genetic algorithm approach for selective harmonic control

    Energy Technology Data Exchange (ETDEWEB)

    Dahidah, Mohamed S.A. [Faculty of Engineering, Multimedia University, 63100, Jalan Multimedia-Cyberjaya, Selangor (Malaysia); Agelidis, Vassilios G. [School of Electrical and Information Engineering, The University of Sydney, NSW (Australia); Rao, Machavaram V. [Faculty of Engineering and Technology, Multimedia University, 75450, Jalan Ayer Keroh Lama-Melaka (Malaysia)

    2008-02-15

    The paper presents an optimal solution for a selective harmonic elimination pulse width modulated (SHE-PWM) technique suitable for a high power inverter used in constant frequency utility applications. The main challenge of solving the associated non-linear equations, which are transcendental in nature and, therefore, have multiple solutions, is the convergence, and therefore, an initial point selected considerably close to the exact solution is required. The paper discusses an efficient hybrid real coded genetic algorithm (HRCGA) that reduces significantly the computational burden, resulting in fast convergence. An objective function describing a measure of the effectiveness of eliminating selected orders of harmonics while controlling the fundamental, namely a weighted total harmonic distortion (WTHD) is derived, and a comparison of different operating points is reported. It is observed that the method was able to find the optimal solution for a modulation index that is higher than unity. The theoretical considerations reported in this paper are verified through simulation and experimentally on a low power laboratory prototype. (author)

  8. A systems approach to mapping transcriptional networks controlling surfactant homeostasis

    Directory of Open Access Journals (Sweden)

    Dave Vrushank

    2010-07-01

    Full Text Available Abstract Background Pulmonary surfactant is required for lung function at birth and throughout life. Lung lipid and surfactant homeostasis requires regulation among multi-tiered processes, coordinating the synthesis of surfactant proteins and lipids, their assembly, trafficking, and storage in type II cells of the lung. The mechanisms regulating these interrelated processes are largely unknown. Results We integrated mRNA microarray data with array independent knowledge using Gene Ontology (GO similarity analysis, promoter motif searching, protein interaction and literature mining to elucidate genetic networks regulating lipid related biological processes in lung. A Transcription factor (TF - target gene (TG similarity matrix was generated by integrating data from different analytic methods. A scoring function was built to rank the likely TF-TG pairs. Using this strategy, we identified and verified critical components of a transcriptional network directing lipogenesis, lipid trafficking and surfactant homeostasis in the mouse lung. Conclusions Within the transcriptional network, SREBP, CEBPA, FOXA2, ETSF, GATA6 and IRF1 were identified as regulatory hubs displaying high connectivity. SREBP, FOXA2 and CEBPA together form a common core regulatory module that controls surfactant lipid homeostasis. The core module cooperates with other factors to regulate lipid metabolism and transport, cell growth and development, cell death and cell mediated immune response. Coordinated interactions of the TFs influence surfactant homeostasis and regulate lung function at birth.

  9. Station-keeping control for a stratospheric airship platform via fuzzy adaptive backstepping approach

    Science.gov (United States)

    Yang, Yueneng; Wu, Jie; Zheng, Wei

    2013-04-01

    This paper presents a novel approach for station-keeping control of a stratospheric airship platform in the presence of parametric uncertainty and external disturbance. First, conceptual design of the stratospheric airship platform is introduced, including the target mission, configuration, energy sources, propeller and payload. Second, the dynamics model of the airship platform is presented, and the mathematical model of its horizontal motion is derived. Third, a fuzzy adaptive backstepping control approach is proposed to develop the station-keeping control system for the simplified horizontal motion. The backstepping controller is designed assuming that the airship model is accurately known, and a fuzzy adaptive algorithm is used to approximate the uncertainty of the airship model. The stability of the closed-loop control system is proven via the Lyapunov theorem. Finally, simulation results illustrate the effectiveness and robustness of the proposed control approach.

  10. A novel PID-based control approach for switched-reluctance motors

    OpenAIRE

    Loria, Antonio; Espinosa-Perez, G.; Chumacero, Erik

    2012-01-01

    We propose a control strategy for switched-reluctance motors with unknown load, which consists in two separate control loops, for the rotor (mechanical) dynamics and the stator (electrical) dynamics. The novelty of the approach resides in using an alternative rotor model which corresponds to that of an harmonic oscillator hence, it is linear in the rotation coordinates. The control law is of proportional-integral-derivative type and it is implemented through a virtual control input, generated...

  11. Data mining Aided Proficient Approach for Optimal Inventory Control in Supply Chain Management

    OpenAIRE

    Chitriki Thotappa; K.Ravindranath

    2010-01-01

    Optimal inventory control is one of the significant tasks in supply chain management. The optimal inventory control methodologies intend to reduce the supply chain (SC) cost by controlling the inventory in an effective manner, such that, the SC members will not be affected by surplus as well as shortage of inventory. In this paper, we propose an efficient approach that effectively utilizes the data mining concepts as well as genetic algorithm for optimal inventory control. The proposed approa...

  12. On the Control of Plants with Hysteresis: Overview and a Prandtl-Ishlinskii Hysteresis Based Control Approach

    Institute of Scientific and Technical Information of China (English)

    Qingqing Wang; Chun-Yi Su; Yonghong Tan

    2005-01-01

    The development of control techniques to mitigate the effects of unknown hysteresis preceding with plants has recently re-attracted significant attention. In this paper, we first give a brief review of presently developed hysteresis models and hysteresis compensating control methods.Then, with the use of the Prandtl-Ishlinskii hysteresis model, we propose a robust adaptive control scheme. The novelty is that the model of hysteresis nonlinearities is firstly fused with the available control techniques without necessarily constructing a hysteresis inverse. The global stability of the adaptive system and tracking a desired trajectory to a certain precision are achieved. Simulations performed on a nonlinear system illustrate and clarify the approach.

  13. Probabilistic safety assessment and optimal control of hazardous technological systems. A marked point process approach

    Energy Technology Data Exchange (ETDEWEB)

    Holmberg, J. [VTT Automation, Espoo (Finland)

    1997-04-01

    The thesis models risk management as an optimal control problem for a stochastic process. The approach classes the decisions made by management into three categories according to the control methods of a point process: (1) planned process lifetime, (2) modification of the design, and (3) operational decisions. The approach is used for optimization of plant shutdown criteria and surveillance test strategies of a hypothetical nuclear power plant. 62 refs. The thesis includes also five previous publications by author.

  14. Probabilistic safety assessment and optimal control of hazardous technological systems. A marked point process approach

    International Nuclear Information System (INIS)

    The thesis models risk management as an optimal control problem for a stochastic process. The approach classes the decisions made by management into three categories according to the control methods of a point process: (1) planned process lifetime, (2) modification of the design, and (3) operational decisions. The approach is used for optimization of plant shutdown criteria and surveillance test strategies of a hypothetical nuclear power plant

  15. MVMO-based approach for optimal placement and tuning of supplementary damping controller

    NARCIS (Netherlands)

    Rueda Torres, J.L.; Gonzalez-Longatt, F.

    2015-01-01

    This paper introduces an approach based on the Swarm Variant of the Mean-Variance Mapping Optimization (MVMO-S) to solve the multi-scenario formulation of the optimal placement and coordinated tuning of power system supplementary damping controllers (POCDCs). The effectiveness of the approach is eva

  16. Experimental demonstration of a classical approach for flexible space structure control: NASA CSI testbeds

    Science.gov (United States)

    Bond, Wie

    1991-01-01

    The results of active control experiments performed for the Mini-Mast truss structure are presented. The primary research objectives were: (1) to develop active structural control concepts and/or techniques; (2) to verify the concept of robust non-minimum-phase compensation for a certain class of non-colocated structural control problems through ground experiments; (3) to verify a 'dipole' concept for persistent disturbance rejection control of flexible structures; and (4) to identify CSI (Control Structure Interaction) issues and areas of emphasis for the next generation of large flexible spacecraft. The classical SISO (Single Input and Single Output) control design approach was employed.

  17. Neural Network Control of CSTR for Reversible Reaction Using Reverence Model Approach

    Directory of Open Access Journals (Sweden)

    Duncan ALOKO

    2007-01-01

    Full Text Available In this work, non-linear control of CSTR for reversible reaction is carried out using Neural Network as design tool. The Model Reverence approach in used to design ANN controller. The idea is to have a control system that will be able to achieve improvement in the level of conversion and to be able to track set point change and reject load disturbance. We use PID control scheme as benchmark to study the performance of the controller. The comparison shows that ANN controller out perform PID in the extreme range of non-linearity.This paper represents a preliminary effort to design a simplified neutral network control scheme for a class of non-linear process. Future works will involve further investigation of the effectiveness of thin approach for the real industrial chemical process

  18. SOWFA Super-Controller: A High-Fidelity Tool for Evaluating Wind Plant Control Approaches

    Energy Technology Data Exchange (ETDEWEB)

    Fleming, P.; Gebraad, P.; van Wingerden, J. W.; Lee, S.; Churchfield, M.; Scholbrock, A.; Michalakes, J.; Johnson, K.; Moriarty, P.

    2013-01-01

    This paper presents a new tool for testing wind plant controllers in the Simulator for Offshore Wind Farm Applications (SOWFA). SOWFA is a high-fidelity simulator for the interaction between wind turbine dynamics and the fluid flow in a wind plant. The new super-controller testing environment in SOWFA allows for the implementation of the majority of the wind plant control strategies proposed in the literature.

  19. Localized and Energy-Efficient Topology Control in Wireless Sensor Networks Using Fuzzy-Logic Control Approaches

    Directory of Open Access Journals (Sweden)

    Yuanjiang Huang

    2014-01-01

    Full Text Available The sensor nodes in the Wireless Sensor Networks (WSNs are prone to failures due to many reasons, for example, running out of battery or harsh environment deployment; therefore, the WSNs are expected to be able to maintain network connectivity and tolerate certain amount of node failures. By applying fuzzy-logic approach to control the network topology, this paper aims at improving the network connectivity and fault-tolerant capability in response to node failures, while taking into account that the control approach has to be localized and energy efficient. Two fuzzy controllers are proposed in this paper: one is Learning-based Fuzzy-logic Topology Control (LFTC, of which the fuzzy controller is learnt from a training data set; another one is Rules-based Fuzzy-logic Topology Control (RFTC, of which the fuzzy controller is obtained through designing if-then rules and membership functions. Both LFTC and RFTC do not rely on location information, and they are localized. Comparing them with other three representative algorithms (LTRT, List-based, and NONE through extensive simulations, our two proposed fuzzy controllers have been proved to be very energy efficient to achieve desired node degree and improve the network connectivity when sensor nodes run out of battery or are subject to random attacks.

  20. A Lyapunov-based three-axis attitude intelligent control approach for unmanned aerial vehicle

    Institute of Scientific and Technical Information of China (English)

    A.H. Mazinan

    2015-01-01

    A novel Lyapunov-based three-axis attitude intelligent control approach via allocation scheme is considered in the proposed research to deal with kinematics and dynamics regarding the unmanned aerial vehicle systems. There is a consensus among experts of this field that the new outcomes in the present complicated systems modeling and control are highly appreciated with respect to state-of-the-art. The control scheme presented here is organized in line with a new integration of the linear-nonlinear control approaches, as long as the angular velocities in the three axes of the system are accurately dealt with in the inner closed loop control. And the corresponding rotation angles are dealt with in the outer closed loop control. It should be noted that the linear control in the present outer loop is first designed through proportional based linear quadratic regulator (PD based LQR) approach under optimum coefficients, while the nonlinear control in the corresponding inner loop is then realized through Lyapunov-based approach in the presence of uncertainties and disturbances. In order to complete the inner closed loop control, there is a pulse-width pulse-frequency (PWPF) modulator to be able to handle on-off thrusters. Furthermore, the number of these on-off thrusters may be increased with respect to the investigated control efforts to provide the overall accurate performance of the system, where the control allocation scheme is realized in the proposed strategy. It may be shown that the dynamics and kinematics of the unmanned aerial vehicle systems have to be investigated through the quaternion matrix and its corresponding vector to avoid presenting singularity of the results. At the end, the investigated outcomes are presented in comparison with a number of potential benchmarks to verify the approach performance.

  1. Efficacy of the "Responsive Classroom" Approach: Results from a 3-Year, Longitudinal Randomized Controlled Trial

    Science.gov (United States)

    Rimm-Kaufman, Sara E.; Larsen, Ross A. A.; Baroody, Alison E.; Curby, Timothy W.; Ko, Michelle; Thomas, Julia B.; Merritt, Eileen G.; Abry, Tashia; DeCoster, Jamie

    2014-01-01

    This randomized controlled field trial examined the efficacy of the Responsive Classroom (RC) approach on student achievement. Schools (n = 24) were randomized into intervention and control conditions; 2,904 children were studied from end of second to fifth grade. Students at schools assigned to the RC condition did not outperform students at…

  2. An impulsive input approach to short time convergent control for linear systems

    NARCIS (Netherlands)

    Weiss, M.; Shtessel, Y.

    2013-01-01

    The paper considers the problem of bringing the state of a controllable linear system to the origin in a very short time. It takes the approach of considering an “ideal” control input consisting of a linear combination of the Dirac delta function and its derivatives that realizes this goal instantan

  3. A Frequency Response Approach to Sliding Control Design for Hydraulic Drives

    DEFF Research Database (Denmark)

    Schmidt, Lasse; Johansen, Per; Andersen, Torben Ole

    2014-01-01

    . However, when considering hydraulic cylinder drives, such full state feedback may not be available, and alternative approaches to conventional methods may be considered. This issue is addressed in this paper in regard to tracking control design for valve controlled hydraulic cylinder drives, and a design...

  4. Development of novel control strategies for single-stage autotrophic nitrogen removal: A process oriented approach

    DEFF Research Database (Denmark)

    Vangsgaard, Anna Katrine; Mauricio Iglesias, Miguel; Gernaey, Krist;

    2014-01-01

    The autotrophic nitrogen removing granular sludge process is a novel and intensified process. However, its stable operation and control remain a challenging issue. In this contribution, a process oriented approach was used to develop, evaluate and benchmark novel control strategies to ensure stable...

  5. Fuzzy-logic approach to HTR nuclear power plant model control

    Energy Technology Data Exchange (ETDEWEB)

    Bubak, M.; Moscinski, J. (Akademia Gorniczo-Hutnicza, Krakow (Poland)); Jewulski, J. (Institute of Physical Chemistry, Krakow (Poland))

    1983-01-01

    The fuzzy-set theory is used to incorporate linguistic 'rules of the thumb' of a human operator in the HTR nuclear power plant controller. The results of the extensive computer simulations are encouraging and confirm the usefulness of this approach in nuclear power plant control. In the Appendix, a short introduction to fuzzy logic is given.

  6. The Astro-WISE approach to quality control for astronomical data

    NARCIS (Netherlands)

    Mc Farland, John; Helmich, Ewout M.; Valentijn, Edwin A.

    2013-01-01

    We present a novel approach to quality control during the processing of astronomical data. Quality control in the Astro-WISE Information System is integral to all aspects of data handing and provides transparent access to quality estimators for all stages of data reduction from the raw image to the

  7. Proportional Transaction Costs in the Robust Control Approach to Option Pricing: The Uniqueness Theorem

    Energy Technology Data Exchange (ETDEWEB)

    El Farouq, Naïma, E-mail: naima.elfarouq@univ-bpclermont.fr [Université Blaise Pascal (Clermont-Ferrand II) (France); Bernhard, Pierre, E-mail: pierre.bernhard@inria.fr [INRIA Sophia Antipolis-Méditerranée (France)

    2015-10-15

    We prove the missing uniqueness theorem for the viscosity solution of a quasi-variational inequality related to a minimax impulse control problem modeling the option pricing with proportional transactions costs. This result makes our robust control approach of option pricing in the interval market model essentially complete.

  8. Analysis and control of Boolean networks a semi-tensor product approach

    CERN Document Server

    Cheng, Daizhan; Li, Zhiqiang

    2010-01-01

    This book presents a new approach to the investigation of Boolean control networks, using the semi-tensor product (STP), which can express a logical function as a conventional discrete-time linear system. This makes it possible to analyze basic control problems.

  9. Programmable System on Chip Distributed Communication and Control Approach for Human Adaptive Mechanical System

    Directory of Open Access Journals (Sweden)

    Ahmad A.M. Faudzi

    2010-01-01

    Full Text Available Problem statement: Communication and control are two main components in any Mechatronics system. They can be designed either by centralized or decentralized approach. Both approaches can be chosen based on application designed and specific requirements of the designer. In this study, decentralized or normally called distributed approach was selected to solved communication and control of a human adaptive mechanical system namely Intelligent Chair Tools (ICT. The ICT seating system is powered by thirty six intelligent pneumatic actuators to facilitate investigation of chair shapes from spring and damping effect of seating and backrest surface. Three studies are proposed from the sitting experiments namely chair shapes, chair spring and chair damping properties. Approach: PSoC microcontroller was selected based on its features of having configurable analog and digital blocks. Its flexible modules and programmable peripherals ease designer in designing the communication and control of ICT in improved and faster way. Three protocols of USB, SPI and I2C were used for the communication system of ICT using PSoC. Flow charts of each communication protocols algorithms were discussed. On the other hand, the control system used PSoC’s ADC and counter modules to read inputs of pressure and encoder respectively. PWM module is used to control the valve and data communication was achieved using I2C module. Block diagram of unified control was discussed for further understandings of the control algorithms. Results: The PSoC specification, development design and experimental evaluation of ICT system are presented and discussed. Three studies of chair shapes, chair spring property and chair damping property from sitting experiment were shown. Conclusion/Recommendations: The PSoC microcontroller selection was discussed and application of its distributed communication and control was successfully applied to ICT. This distributed approach can be applied to other

  10. A NEW FUZZY LOGIC BASED SPACE VECTOR MODULATION APPROACH ON DIRECT TORQUE CONTROLLED INDUCTION MOTORS

    Directory of Open Access Journals (Sweden)

    Fatih Korkmaz

    2013-11-01

    Full Text Available The induction motors are indispensable motor types for industrial applications due to its wellknown advantages. Therefore, many kind of control scheme are proposed for induction motors over the past years and direct torque control has gained great importance inside of them due to fast dynamic torque response behavior and simple control structure. This paper suggests a new approach on the direct torque controlled induction motors, Fuzzy logic based space vector modulation, to overcome disadvantages of conventional direct torque control like high torque ripple. In the proposed approach, optimum switching states are calculated by fuzzy logic controller and applied by space vector pulse width modulator to voltage source inverter. In order to test and compare the proposed DTC scheme with conventional DTC scheme simulations, in Matlab/Simulink, have been carried out in different speed and load conditions. The simulation results showed that a significant improvement in the dynamic torque and speed responses when compared to the conventional DTC scheme.

  11. Feedback Linearization approach for Standard and Fault Tolerant control: Application to a Quadrotor UAV Testbed

    International Nuclear Information System (INIS)

    In this paper the control problem of a quadrotor vehicle experiencing a rotor failure is investigated. We develop a Feedback linearization approach to design a controller whose task is to make the vehicle performs trajectory following. Then we use the same approach to design a controller whose task is to make the vehicle enter a stable spin around its vertical axis, while retaining zero angular velocities around the other axis when a rotor failure is present. These conditions can be exploited to design a second control loop, which is used to perform trajectory following. The proposed double control loop architecture allows the vehicle to perform both trajectory and roll/pitch control. At last, to test the robustness of the feedback linearization technique, we applied wind to the quadrotor in mid flight

  12. Constraint-based control of boiler efficiency: A data-mining approach

    Energy Technology Data Exchange (ETDEWEB)

    Song, Z.; Kusiak, A. [University of Iowa, Iowa City, IA (United States)

    2007-02-15

    In this paper, a data-mining approach is used to develop a model for optimizing the efficiency of an electric-utility boiler subject to operating constraints. Selection of process variables to optimize combustion efficiency is discussed. The selected variables are critical for control of combustion efficiency of a coal-fired boiler in the presence of operating constraints. Two schemes of generating control settings and updating control variables are evaluated. One scheme is based on the controllable and noncontrollable variables. The second one incorporates response variables into the clustering process. The process control scheme based on the response variables produces the smallest variance of the target variable due to reduced coupling among the process variables. An industrial case study, and its implementation illustrate the control approach developed in this paper.

  13. A HACCP-based approach to mastitis control in dairy herds. Part 1: Development

    Directory of Open Access Journals (Sweden)

    Beekhuis-Gibbon Lies

    2011-03-01

    Full Text Available Abstract Hazard Analysis and Critical Control Points (HACCP systems are a risk based preventive approach developed to increase levels of food safety assurance. This is part 1 of a pilot study on the development, implementation and evaluation of a HACCP-based approach for the control of good udder health in dairy cows. The paper describes the use of a novel approach based on a deconstruction of the infectious process in mastitis to identify Critical Control Points (CCPs and develop a HACCP-based system to prevent and control mastitis in dairy herds. The approach involved the creation of an Infectious Process Flow Diagram, which was then cross-referenced to two production process flow diagrams of the milking process and cow management cycle. The HACCP plan developed, may be suitable for customisation and implementation on dairy farms. This is a logical, systematic approach to the development of a mastitis control programme that could be used as a template for the development of control programmes for other infectious diseases in the dairy herd.

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

    International Nuclear Information System (INIS)

    Full-text: Humankind's ongoing battle with pest species spans millennia. Pests cause or carry disease, damage or consume food crops and other resources, and drive global environmental change. Conventional approaches to pest management usually involve lethal control, but such approaches are costly, of varying efficiency and often have ethical issues. Thus, pest management via control of reproductive output is increasingly considered an optimal solution. One of the most successful such 'fertility control' strategies developed to date is the sterile male technique (SMT), in which large numbers of sterile males are released into a population each generation. However, this approach is time-consuming, labour- intensive and costly. We use mathematical models to test a new twist on the SMT, using maternally inherited mitochondrial (mtDNA) mutations that affect male, but not female reproductive fitness. 'Trojan females' carrying such mutations, and their female descendants, produce 'sterile-male'-equivalents under natural conditions over multiple generations. We find that the Trojan Female Technique (TFT) has the potential to be a novel humane approach for pest control. Single large releases and relatively few small repeat releases of Trojan females both provided effective and persistent control within relatively few generations. Although greatest efficacy was predicted for high-turnover species, the additive nature of multiple releases made the TFT applicable to the full range of life histories modelled. The extensive conservation of mtDNA among eukaryotes suggests this approach could have broad utility for pest control. (author)

  15. A Delta Operator Approach for the Discrete-Time Active Disturbance Rejection Control on Induction Motors

    Directory of Open Access Journals (Sweden)

    John Cortés-Romero

    2013-01-01

    Full Text Available The problem of active disturbance rejection control of induction motors is tackled by means of a generalized PI observer based discrete-time control, using the delta operator approach as the methodology of analyzing the sampled time process. In this scheme, model uncertainties and external disturbances are included in a general additive disturbance input which is to be online estimated and subsequently rejected via the controller actions. The observer carries out the disturbance estimation, thus reducing the complexity of the controller design. The controller efficiency is tested via some experimental results, performing a trajectory tracking task under load variations.

  16. An Optimal Control Approach to Inventory-Production Systems with Weibull Distributed Deterioration

    Directory of Open Access Journals (Sweden)

    Md. A. Baten

    2009-01-01

    Full Text Available Problem statement: We studied the inventory-production system with two-parameter Weibull distributed deterioration items. Approach: The inventory model was developed as linear optimal control problem and by the Pontryagin maximum principle, the optimal control problem was solved analytically to obtain the optimal solution of the problem. Results: It was then illustrated with the help of an example. By the principle of optimality we also established the Riccati based solution of the Hamilton-Jacobi-Bellman (HJB equation associated with this control problem. Conclusion: As an application to quadratic control theory we showed an optimal control policy to exist from the optimality conditions in the HJB equation.

  17. Robust Neural Network Control of Electrically Driven Robot Manipulator using Backstepping Approach

    Directory of Open Access Journals (Sweden)

    Seyed Ehsan Shafiei

    2010-02-01

    Full Text Available A novel approach to neural network based tracking-control of robot manipulator including actuator dynamics is proposed by using of backstepping method. A simple two-step backstepping is considered for an nlink robotic system, and a feedforward neural controller is designed at second step where structured and unstructured uncertainties in robot dynamics and actuator model are approximated by this neural controller. Bounds of network reconstruction error and other imprecisions are estimated adaptively and for compensating them, a robust control signal is added and modified. Stability analysis is performed by the Lyapunov direct method and performance efficiency of the proposed controller is justified by the simulations.

  18. Optimal higher order learning adaptive control approach for a class of SISO nonlinear systems

    Institute of Scientific and Technical Information of China (English)

    Ronghu CHI; Zhongsheng HOU

    2005-01-01

    In this paper,an optimal higher order learning adaptive control approach is developed for a class of SISO nonlinear systems.This design is model-free and depends directly on pseudo-partial-derivatives derived on-line from the input and output information of the system.A novel weighted one-step-ahead control criterion function is proposed for the control law.The convergence analysis shows that the proposed control law can guarantee the convergence under the assumption that the desired output is a set point.Simulation examples are provided for nonlinear systems to illustrate the better performance of the higher order learning adaptive control.

  19. Cooperative control of multi-agent systems a consensus region approach

    CERN Document Server

    Li, Zhongkui

    2014-01-01

    Distributed controller design is generally a challenging task, especially for multi-agent systems with complex dynamics, due to the interconnected effect of the agent dynamics, the interaction graph among agents, and the cooperative control laws. Cooperative Control of Multi-Agent Systems: A Consensus Region Approach offers a systematic framework for designing distributed controllers for multi-agent systems with general linear agent dynamics, linear agent dynamics with uncertainties, and Lipschitz nonlinear agent dynamics.Beginning with an introduction to cooperative control and graph theory,

  20. A New Approach to HVDC Grid Voltage Control Based on Generalized State Feedback

    DEFF Research Database (Denmark)

    Beerten, Jef; Eriksson, Robert; Van Hertem, Dirk

    2014-01-01

    in the system hamper a straight-forward definition of the power sharing. The use of a common DC voltage signal for the control can solve some of the problems. However, it disregards some of the benefits that are associated with the use of a local voltage control, such as the tendency of a controller using local...... voltage feedback signals to solve problems locally which can reduce the stress on the AC system. Furthermore, it provides no direct means to obtain different system responses for different converter outages. The control approach presented in this paper aims at improving the DC voltage droop control...

  1. Structural modelling and control design under incomplete parameter information: The maximum-entropy approach

    Science.gov (United States)

    Hyland, D. C.

    1983-01-01

    A stochastic structural control model is described. In contrast to the customary deterministic model, the stochastic minimum data/maximum entropy model directly incorporates the least possible a priori parameter information. The approach is to adopt this model as the basic design model, thus incorporating the effects of parameter uncertainty at a fundamental level, and design mean-square optimal controls (that is, choose the control law to minimize the average of a quadratic performance index over the parameter ensemble).

  2. Structural analysis and design of multivariable control systems: An algebraic approach

    Science.gov (United States)

    Tsay, Yih Tsong; Shieh, Leang-San; Barnett, Stephen

    1988-01-01

    The application of algebraic system theory to the design of controllers for multivariable (MV) systems is explored analytically using an approach based on state-space representations and matrix-fraction descriptions. Chapters are devoted to characteristic lambda matrices and canonical descriptions of MIMO systems; spectral analysis, divisors, and spectral factors of nonsingular lambda matrices; feedback control of MV systems; and structural decomposition theories and their application to MV control systems.

  3. Advanced control approach for hybrid systems based on solid oxide fuel cells

    International Nuclear Information System (INIS)

    Highlights: • Advanced new control system for SOFC based hybrid plants. • Proportional–Integral approach with feed-forward technology. • Good control of fuel cell temperature. • All critical properties maintained inside safe conditions. - Abstract: This paper shows a new advanced control approach for operations in hybrid systems equipped with solid oxide fuel cell technology. This new tool, which combines feed-forward and standard proportional–integral techniques, controls the system during load changes avoiding failures and stress conditions detrimental to component life. This approach was selected to combine simplicity and good control performance. Moreover, the new approach presented in this paper eliminates the need for mass flow rate meters and other expensive probes, as usually required for a commercial plant. Compared to previous works, better performance is achieved in controlling fuel cell temperature (maximum gradient significantly lower than 3 K/min), reducing the pressure gap between cathode and anode sides (at least a 30% decrease during transient operations), and generating a higher safe margin (at least a 10% increase) for the Steam-to-Carbon Ratio. This new control system was developed and optimized using a hybrid system transient model implemented, validated and tested within previous works. The plant, comprising the coupling of a tubular solid oxide fuel cell stack with a microturbine, is equipped with a bypass valve able to connect the compressor outlet with the turbine inlet duct for rotational speed control. Following model development and tuning activities, several operative conditions were considered to show the new control system increased performance compared to previous tools (the same hybrid system model was used with the new control approach). Special attention was devoted to electrical load steps and ramps considering significant changes in ambient conditions

  4. A new approach to control the modified LinVerter for high frequency applications

    DEFF Research Database (Denmark)

    Farhang, Peyman; Mátéfi-Tempfli, Stefan

    2016-01-01

    In this paper not only a modified multi-device LinVerter is proposed but also a novel approach to control this topology is introduced. This topology is able to improve the conventional LinVerter performance using parallel power devices and designing a sequential switching scheme. In addition, from...... control perspective, a novel control approach based on bidirectional interface between LTspice and MATLAB is created. In this case, the circuit is modeled in LTspice environment and a Chaos Optimization Algorithm (COA) is coded in MATLAB in order to find out the optimal solution in control process....... In fact, this new approach combines the advantages of LTspice for simulation of different circuit configurations using actual component obtained from manufactures' models with advanced intelligent techniques capabilities from COA in MATLAB. First, the performance of proposed multi-device LinVerter along...

  5. Active queue management controller design for TCP communication networks: Variable structure control approach

    International Nuclear Information System (INIS)

    On the basis of variable structure control (VSC), an active queue management (AQM) controller is presented for a class of TCP communication networks. In the TCP/IP networks, the packet drop probability is limited between 0 and 1. Therefore, we modeled TCP/AQM as a rate-based non-linear system with a saturated input. The objective of the VSC-based AQM controller is to achieve the desired queue size and to guarantee the asymptotic stability of the closed-loop TCP non-linear system with saturated input. The performance and effectiveness of the proposed control law are then validated for different network scenarios through numerical simulations in both MATLAB and Network Simulator-2 (NS-2). Both sets of simulation results have confirmed that the proposed scheme outperforms other AQM schemes.

  6. Naturalizing sense of agency with a hierarchical event-control approach.

    Directory of Open Access Journals (Sweden)

    Devpriya Kumar

    Full Text Available Unraveling the mechanisms underlying self and agency has been a difficult scientific problem. We argue for an event-control approach for naturalizing the sense of agency by focusing on the role of perception-action regularities present at different hierarchical levels and contributing to the sense of self as an agent. The amount of control at different levels of the control hierarchy determines the sense of agency. The current study investigates this approach in a set of two experiments using a scenario containing multiple agents sharing a common goal where one of the agents is partially controlled by the participant. The participant competed with other agents for achieving the goal and subsequently answered questions on identification (which agent was controlled by the participant, the degree to which they are confident about their identification (sense of identification and the degree to which the participant believed he/she had control over his/her actions (sense of authorship. Results indicate a hierarchical relationship between goal-level control (higher level and perceptual-motor control (lower level for sense of agency. Sense of identification ratings increased with perceptual-motor control when the goal was not completed but did not vary with perceptual-motor control when the goal was completed. Sense of authorship showed a similar interaction effect only in experiment 2 that had only one competing agent unlike the larger number of competing agents in experiment 1. The effect of hierarchical control can also be seen in the misidentification pattern and misidentification was greater with the agent affording greater control. Results from the two studies support the event-control approach in understanding sense of agency as grounded in control. The study also offers a novel paradigm for empirically studying sense of agency and self.

  7. Robust H∞ Control for a Class of Nonlinear Distributed Parameter Systems via Proportional-Spatial Derivative Control Approach

    Directory of Open Access Journals (Sweden)

    Cheng-Dong Yang

    2014-01-01

    Full Text Available This paper addresses the problem of robust H∞ control design via the proportional-spatial derivative (P-sD control approach for a class of nonlinear distributed parameter systems modeled by semilinear parabolic partial differential equations (PDEs. By using the Lyapunov direct method and the technique of integration by parts, a simple linear matrix inequality (LMI based design method of the robust H∞ P-sD controller is developed such that the closed-loop PDE system is exponentially stable with a given decay rate and a prescribed H∞ performance of disturbance attenuation. Moreover, a suboptimal H∞ controller is proposed to minimize the attenuation level for a given decay rate. The proposed method is successfully employed to address the control problem of the FitzHugh-Nagumo (FHN equation, and the achieved simulation results show its effectiveness.

  8. Optimal speech motor control and token-to-token variability: a Bayesian modeling approach.

    Science.gov (United States)

    Patri, Jean-François; Diard, Julien; Perrier, Pascal

    2015-12-01

    The remarkable capacity of the speech motor system to adapt to various speech conditions is due to an excess of degrees of freedom, which enables producing similar acoustical properties with different sets of control strategies. To explain how the central nervous system selects one of the possible strategies, a common approach, in line with optimal motor control theories, is to model speech motor planning as the solution of an optimality problem based on cost functions. Despite the success of this approach, one of its drawbacks is the intrinsic contradiction between the concept of optimality and the observed experimental intra-speaker token-to-token variability. The present paper proposes an alternative approach by formulating feedforward optimal control in a probabilistic Bayesian modeling framework. This is illustrated by controlling a biomechanical model of the vocal tract for speech production and by comparing it with an existing optimal control model (GEPPETO). The essential elements of this optimal control model are presented first. From them the Bayesian model is constructed in a progressive way. Performance of the Bayesian model is evaluated based on computer simulations and compared to the optimal control model. This approach is shown to be appropriate for solving the speech planning problem while accounting for variability in a principled way.

  9. Optimal speech motor control and token-to-token variability: a Bayesian modeling approach.

    Science.gov (United States)

    Patri, Jean-François; Diard, Julien; Perrier, Pascal

    2015-12-01

    The remarkable capacity of the speech motor system to adapt to various speech conditions is due to an excess of degrees of freedom, which enables producing similar acoustical properties with different sets of control strategies. To explain how the central nervous system selects one of the possible strategies, a common approach, in line with optimal motor control theories, is to model speech motor planning as the solution of an optimality problem based on cost functions. Despite the success of this approach, one of its drawbacks is the intrinsic contradiction between the concept of optimality and the observed experimental intra-speaker token-to-token variability. The present paper proposes an alternative approach by formulating feedforward optimal control in a probabilistic Bayesian modeling framework. This is illustrated by controlling a biomechanical model of the vocal tract for speech production and by comparing it with an existing optimal control model (GEPPETO). The essential elements of this optimal control model are presented first. From them the Bayesian model is constructed in a progressive way. Performance of the Bayesian model is evaluated based on computer simulations and compared to the optimal control model. This approach is shown to be appropriate for solving the speech planning problem while accounting for variability in a principled way. PMID:26497359

  10. PID Control in the Third Millennium Lessons Learned and New Approaches

    CERN Document Server

    Visioli, Antonio

    2012-01-01

    The early 21st century has seen a renewed interest in research in the widely-adopted proportional-integral-derivative (PID) controllers. PID Control in the Third Millennium provides an overview of the advances made as a result. Featuring: ·        new approaches for controller tuning; ·        control structures and configurations for more efficient control; ·        practical issues in PID implementation; and ·        non-standard approaches to PID including fractional-order, event-based, nonlinear, data-driven and predictive control; the nearly twenty chapters provide a state-of-the-art resumé of PID controller theory, design and realization. Each chapter has specialist authorship and ideas clearly characterized from both academic and industrial viewpoints. Advances in Industrial Control aims to report and encourage the transfer of technology in control engineering. The rapid development of control technology has an impact on all areas of the control discipline. The series o...

  11. A layered approach to structural control system design for the JPL phase B testbed

    Science.gov (United States)

    Chu, Cheng-Chih; O'Brien, John

    1993-01-01

    This paper describes our efforts in structural control experiments for a flexible precision structure using both passive and active control. Specifically, a layered structural control approach utilizing passive viscous dampers, colocated and noncolocated active control is used. The passive dampers and active colocated control loops are used to enhance stability and robustness and the noncolocated multivariable controller is designed with respect to a partially controlled structure to further improve the performance. Our approach to the multivariable design problem requires not only a state space model description of the plant, but also an accompanying uncertainty model. To support the multivariable robust control design development, a significant effort in system identification was undertaken. The process of identification and identified results are discussed. Noncolocated controllers are designed using the H(infinity)/mu-synthesis methodology. The order of the controller is typically large, hence, model reduction is performed for practical digital implementation on a real-time control system developed at JPL. Finally, experimental results are presented and some of lessons are discussed.

  12. Integrated Approach Model of Risk, Control and Auditing of Accounting Information Systems

    Directory of Open Access Journals (Sweden)

    Claudiu BRANDAS

    2013-01-01

    Full Text Available The use of IT in the financial and accounting processes is growing fast and this leads to an increase in the research and professional concerns about the risks, control and audit of Ac-counting Information Systems (AIS. In this context, the risk and control of AIS approach is a central component of processes for IT audit, financial audit and IT Governance. Recent studies in the literature on the concepts of risk, control and auditing of AIS outline two approaches: (1 a professional approach in which we can fit ISA, COBIT, IT Risk, COSO and SOX, and (2 a research oriented approach in which we emphasize research on continuous auditing and fraud using information technology. Starting from the limits of existing approaches, our study is aimed to developing and testing an Integrated Approach Model of Risk, Control and Auditing of AIS on three cycles of business processes: purchases cycle, sales cycle and cash cycle in order to improve the efficiency of IT Governance, as well as ensuring integrity, reality, accuracy and availability of financial statements.

  13. Development of an inexact fuzzy flexible programming approach for environmental pollution control

    Science.gov (United States)

    Lu, H. W.; Huang, G. H.; Maqsood, I.

    2010-12-01

    Optimization techniques have been widely applied to solving environmental management problems, particularly for regional air quality management systems where potential air pollutions arising from improper management would seriously threaten human health. An inexact fuzzy flexible programming approach is developed to facilitate decision support for air quality management. It can tackle both stipulation uncertainty and parameter uncertainty in the objective function and constraints. Upon the previous research efforts, the most significant improvement of this approach is the introduction of multiple control variables corresponding to the objective function and all constraints. This attempt makes it possible for the constraints to be relaxed under respective levels, such that a more satisfactory objective value may be obtained. The impact of each constraint on the system outputs can also be further interpreted. The proposed approach would be helpful for such systems where the decision makers prefer to not only find out an air pollution control scheme with a satisfaction level as high as possible, but also mitigate the uncertainty in decision making. A regional air pollution control problem is then studied to demonstrate the applicability of the developed approach. A variety of management strategies for air pollutants allocation and treatment are suggested in terms of the optimal solutions to decision variables. Comparison between the optimal solutions from the proposed approach and those from a conventional fuzzy flexible programming model is undertaken. It can be found that neither the management strategies nor the priorities of pollutants allocation obtained from the two models are the same. The satisfaction level of the proposed approach (taking the average value of optimized solutions of control variables for comparison) is always higher than that of the existing approach, indicating the superiority of the proposed approach in handling many air pollution control

  14. Nonlinear control for a diesel engine: A CLF-based approach

    Directory of Open Access Journals (Sweden)

    Kuzmych Olena

    2014-12-01

    Full Text Available In this paper, we propose a control Lyapunov function based on a nonlinear controller for a turbocharged diesel engine. A model-based approach is used which predicts the experimentally observed engine performance for a biodiesel. The basic idea is to develop an inverse optimal control and to employ a Lyapunov function in order to achieve good performances. The obtained controller gain guarantees the global convergence of the system and regulates the flows for the variable geometry turbocharger as well as exhaust gas recirculation systems in order to minimize the NOx emission and the smoke of a biodiesel engine. Simulation of the control performances based on professional software and experimental results show the effectiveness of this approach.

  15. Towards Current Profile Control in ITER: Potential Approaches and Research Needs

    Science.gov (United States)

    Schuster, E.; Barton, J. E.; Wehner, W. P.

    2014-10-01

    Many challenging plasma control problems still need to be addressed in order for the ITER Plasma Control System (PCS) to be able to successfully achieve the ITER project goals. For instance, setting up a suitable toroidal current density profile is key for one possible advanced scenario characterized by noninductive sustainment of the plasma current and steady-state operation. The nonlinearity and high dimensionality exhibited by the plasma demand a model-based current-profile control synthesis procedure that can accommodate this complexity through embedding the known physics within the design. The development of a model capturing the dynamics of the plasma relevant for control design enables not only the design of feedback controllers for regulation or tracking but also the design of optimal feedforward controllers for a systematic model-based approach to scenario planning, the design of state estimators for a reliable real-time reconstruction of the plasma internal profiles based on limited and noisy diagnostics, and the development of a fast predictive simulation code for closed-loop performance evaluation before implementation. Progress towards control-oriented modeling of the current profile evolution and associated control design has been reported following both data-driven and first-principles-driven approaches. An overview of these two approaches will be provided, as well as a discussion on research needs associated with each one of the model applications described above. Supported by the US Department of Energy under DE-SC0001334 and DE-SC0010661.

  16. State-of-the-art in Comprehensive Cascade Control Approach through Monte-Carlo Based Representation

    Directory of Open Access Journals (Sweden)

    A.H. Mazinan

    2015-10-01

    Full Text Available The research relies on the comprehensive cascade control approach to be developed in the area of spacecraft, as long as Monte-Carlo based representation is taken into real consideration with respect to state-of-the-art. It is obvious that the conventional methods do not have sufficient merit to be able to deal with such a process under control, constantly, provided that a number of system parameters variations are to be used in providing real situations. It is to note that the new insights in the area of the research’s topic are valuable to outperform a class of spacecrafts performance as the realizations of the acquired results are to be addressed in both real and academic environments. In a word, there are a combination of double closed loop based upon quaternion based control approach in connection with Euler based control approach to handle the three-axis rotational angles and its rates, synchronously, in association with pulse modulation analysis and control allocation, where the dynamics and kinematics of the present system under control are analyzed. A series of experiments are carried out to consider the approach performance in which the aforementioned Monte-Carlo based representation is to be realized in verifying the investigated outcomes.

  17. A non-iterative cascaded predictive control approach for control of irrigation canals

    NARCIS (Netherlands)

    Negenborn, R.R.; Sahin, A.; Lukszo, Z.; De Schutter, B.; Morari, M.

    2009-01-01

    Irrigation canals transport water from water sources (such as large rivers and lakes) to water users (such as farmers). Irrigation canals are typically very large in nature, covering vast geographical areas, and involving a significant number of control actuators, such as pumps, gates, and locks. Th

  18. An efficient water flow control approach for water heaters in direct load control

    NARCIS (Netherlands)

    Belov, Alexander; Meratnia, Nirvana; Zwaag, van der Berend Jan; Havinga, Paul

    2014-01-01

    Tank water heaters (WHs) are present in a prevailing number of European households. Serving as energy buffers WHs have come under the spotlight of various direct load control (DLC) programs over the last few decades. Although DLC has proven to be an efficient measure towards daily peak demand shavin

  19. A generic approach for examining the effectiveness of traffic control devices in school zones.

    Science.gov (United States)

    Zhao, Xiaohua; Li, Jiahui; Ding, Han; Zhang, Guohui; Rong, Jian

    2015-09-01

    The effectiveness and performance of traffic control devices in school zones have been impacted significantly by many factors, such as driver behavioral attributes, roadway geometric features, environmental characteristics, weather and visibility conditions, region-wide traffic regulations and policies, control modes, etc. When deploying traffic control devices in school zones, efforts are needed to clarify: (1) whether traffic control device installation is warranted; and (2) whether other device effectively complements this traffic control device and strengthens its effectiveness. In this study, a generic approach is developed to examine and evaluate the effectiveness of various traffic control devices deployed in school zones through driving simulator-based experiments. A Traffic Control Device Selection Model (TCDSM) is developed and two representative school zones are selected as the testbed in Beijing for driving simulation implementation to enhance its applicability. Statistical analyses are conducted to extract the knowledge from test data recorded by a driving simulator. Multiple measures of effectiveness (MOEs) are developed and adopted including average speed, relative speed difference, and standard deviation of acceleration for traffic control device performance quantification. The experimental tests and analysis results reveal that the appropriateness of the installation of certain traffic control devices can be statistically verified by TCDSM. The proposed approach provides a generic framework to assess traffic control device performance in school zones including experiment design, statistical formulation, data analysis, simulation model implementation, data interpretation, and recommendation development. PMID:26072182

  20. Fast engineering optimization: A novel highly effective control parameterization approach for industrial dynamic processes.

    Science.gov (United States)

    Liu, Ping; Li, Guodong; Liu, Xinggao

    2015-09-01

    Control vector parameterization (CVP) is an important approach of the engineering optimization for the industrial dynamic processes. However, its major defect, the low optimization efficiency caused by calculating the relevant differential equations in the generated nonlinear programming (NLP) problem repeatedly, limits its wide application in the engineering optimization for the industrial dynamic processes. A novel highly effective control parameterization approach, fast-CVP, is first proposed to improve the optimization efficiency for industrial dynamic processes, where the costate gradient formulae is employed and a fast approximate scheme is presented to solve the differential equations in dynamic process simulation. Three well-known engineering optimization benchmark problems of the industrial dynamic processes are demonstrated as illustration. The research results show that the proposed fast approach achieves a fine performance that at least 90% of the computation time can be saved in contrast to the traditional CVP method, which reveals the effectiveness of the proposed fast engineering optimization approach for the industrial dynamic processes.

  1. CONSOLIDATION POLICY: PAST, PRESENT AND FUTURE APPROACHES TO THE CONCEPT OF CONTROL

    Directory of Open Access Journals (Sweden)

    Ienciu Alin Ionel

    2010-07-01

    Full Text Available Preparing consolidated financial statements has been a common practice for groups of companies around the world for a relatively long time, going back one century in the USA and tens of years in different European countries.A far-reaching issue regarding consolidation accounting policy is the concept of control, as it holds a crucial role in determining the basis of consolidation and the applicable method of consolidation and subsequently in influencing the content of the group financial statements. We focus in our article on the concept of exclusive control as it is approached by the relevant International, American and European standards, casting light also on possible future developments of this concept. The objective of our study is to acknowledge the differences and similarities between the approaches to the control concept, closing with the presentation of the influences of these approaches on the basis of consolidation.

  2. Rotor Current Control of DFIG for Improving Fault Ride - Through Using a Novel Sliding Mode Control Approach

    Science.gov (United States)

    Cai, Guowei; Liu, Cheng; Yang, Deyou

    2013-11-01

    The doubly fed induction generators (DFIG) have been recognized as the dominant technology used in wind power generation systems with the rapid development of wind power. However, continuous operation of DFIG may cause a serious wind turbine generators tripping accident, due to destructive over-current in the rotor winding which is caused by the power system fault or inefficient fault ride-through (FRT) strategy. A new rotor current control scheme in the rotor-side converter (RSC) ispresented to enhance FRT capacities of grid-connected DFIG. Due to the strongly nonlinear nature of DFIG and insensitive to DFIG parameter's variations, a novel sliding mode controller was designed. The controller combines extended state observer (ESO) with sliding model variable structure control theory. The simulation is carried out to verify the effectiveness of the proposed control approach under various types of grid disturbances. It is shown that the proposed controller provides enhanced transient features than the classic proportional-integral control. The proposed control method can effectively reduce over-current in the RSC, and the transient pulse value of electromagnetic torque is too large under power grid fault.

  3. A new digital approach to design multivariable robust optimal control systems

    Institute of Scientific and Technical Information of China (English)

    LIU Xiang; CHEN Lin; SUN You-xian

    2005-01-01

    This paper presents a new design of robust optimal controller for multivariable system. The row characteristic functions of a linear multivariable system and dynamic decoupling of its equivalent system, were applied to change the transfer function matrix of a closed-loop system into a normal function matrix, so that robustH∞ optimal stability is guaranteed. Furthermore,for the decoupled equivalent control system the l∞ optimization approach is used to have the closed-loop system embody optimal time domain indexes. A successful application on a heater control system verified the excellence of the new control scheme.

  4. PFC design via FRIT Approach for Adaptive Output Feedback Control of Discrete-time Systems

    Science.gov (United States)

    Mizumoto, Ikuro; Takagi, Taro; Fukui, Sota; Shah, Sirish L.

    This paper deals with a design problem of an adaptive output feedback control for discrete-time systems with a parallel feedforward compensator (PFC) which is designed for making the augmented controlled system ASPR. A PFC design scheme by a FRIT approach with only using an input/output experimental data set will be proposed for discrete-time systems in order to design an adaptive output feedback control system. Furthermore, the effectiveness of the proposed PFC design method will be confirmed through numerical simulations by designing adaptive control system with adaptive NN (Neural Network) for an uncertain discrete-time system.

  5. H~ Estimation Approach to Active Noise Control: Theory, Algorithm and Real-Time Implementation

    Directory of Open Access Journals (Sweden)

    Bambang Riyanto

    2003-11-01

    Full Text Available This paper presents an H¥ estimation approach to active control of acoustic noise inside an enclosure. It is shown how H¥ filter theory and algorithm can be effectively applied to active noise control to provide important robustness property. Real-time implementation of the algorithm is performed on Digital Signal Processor. Experimental comparison to conventional FxLMS algorithm for active noise control is presented for both single channel and multichannel cases. While providing some new results, this paper also serves as a brief review on H¥ filter theory and on active noise control.

  6. Lattice hydrodynamic model based traffic control: A transportation cyber-physical system approach

    Science.gov (United States)

    Liu, Hui; Sun, Dihua; Liu, Weining

    2016-11-01

    Lattice hydrodynamic model is a typical continuum traffic flow model, which describes the jamming transition of traffic flow properly. Previous studies in lattice hydrodynamic model have shown that the use of control method has the potential to improve traffic conditions. In this paper, a new control method is applied in lattice hydrodynamic model from a transportation cyber-physical system approach, in which only one lattice site needs to be controlled in this control scheme. The simulation verifies the feasibility and validity of this method, which can ensure the efficient and smooth operation of the traffic flow.

  7. Biologically inspired control of humanoid robot arms robust and adaptive approaches

    CERN Document Server

    Spiers, Adam; Herrmann, Guido

    2016-01-01

    This book investigates a biologically inspired method of robot arm control, developed with the objective of synthesising human-like motion dynamically, using nonlinear, robust and adaptive control techniques in practical robot systems. The control method caters to a rising interest in humanoid robots and the need for appropriate control schemes to match these systems. Unlike the classic kinematic schemes used in industrial manipulators, the dynamic approaches proposed here promote human-like motion with better exploitation of the robot’s physical structure. This also benefits human-robot interaction. The control schemes proposed in this book are inspired by a wealth of human-motion literature that indicates the drivers of motion to be dynamic, model-based and optimal. Such considerations lend themselves nicely to achievement via nonlinear control techniques without the necessity for extensive and complex biological models. The operational-space method of robot control forms the basis of many of the techniqu...

  8. Attitude Stabilization Control of a Quadrotor UAV by Using Backstepping Approach

    Directory of Open Access Journals (Sweden)

    Xing Huo

    2014-01-01

    Full Text Available The modeling and attitude stabilization control problems of a four-rotor vertical takeoff and landing unmanned air vehicle (UAV known as the quadrotor are investigated. The quadrotor’s attitude is represented by the unit quaternion rather than Euler angles to avoid singularity problem. Taking dynamical behavior of motors into consideration and ignoring aerodynamic effect, a nonlinear controller is developed to stabilize the attitude. The control design is accomplished by using backstepping control technique. The proposed control law is based on the compensation for the Coriolis and gyroscope torques. Applying Lyapunov stability analysis proves that the closed-loop attitude system is asymptotic stable. Moreover, the controller can guarantee that all the states of the system are uniformly ultimately bounded in the presence of external disturbance torque. The effectiveness of the proposed control approach is analytically authenticated and also validated via simulation study.

  9. Static Output-Feedback Control for Vehicle Suspensions: A Single-Step Linear Matrix Inequality Approach

    Directory of Open Access Journals (Sweden)

    Josep Rubió-Massegú

    2013-01-01

    Full Text Available In this paper, a new strategy to design static output-feedback controllers for a class of vehicle suspension systems is presented. A theoretical background on recent advances in output-feedback control is first provided, which makes possible an effective synthesis of static output-feedback controllers by solving a single linear matrix inequality optimization problem. Next, a simplified model of a quarter-car suspension system is proposed, taking the ride comfort, suspension stroke, road holding ability, and control effort as the main performance criteria in the vehicle suspension design. The new approach is then used to design a static output-feedback H∞ controller that only uses the suspension deflection and the sprung mass velocity as feedback information. Numerical simulations indicate that, despite the restricted feedback information, this static output-feedback H∞ controller exhibits an excellent behavior in terms of both frequency and time responses, when compared with the corresponding state-feedback H∞ controller.

  10. Complex Event Processing Approach To Automated Monitoring Of Particle Accelerator And Its Control System

    OpenAIRE

    Karol Grzegorczyk; Vito Baggiolini; Krzysztof Zieliński

    2014-01-01

    This article presents the design and implementation of a software component for automated monitoring and diagnostic information analysis of a particle accelerator and its control system. The information that is analyzed can be seen as streams of events. A Complex Event Processing (CEP) approach to event processing was selected. The main advantage of this approach is the ability to continuously query data coming from several streams. The presented software component is based on Esper, the most...

  11. A bayesian belief networks approach to risk control in construction projects

    OpenAIRE

    Chivatá Cárdenas, I.C.; Al-jibouri, S.H.S.; Halman, J.I.M.; Telichenko, V.; Volkov, A.; Bilchuk, I.

    2012-01-01

    Although risk control is a key step in risk management of construction projects, very often risk measures used are based merely on personal experience and engineering judgement rather than analysis of comprehensive information relating to a specific risk. This paper deals with an approach to provide better information to derive relevant and effective risk measures for specific risks. The approach relies on developing risk models to represent interactions between risk factors and carrying out ...

  12. An LMI-based unified approach to reduced-order controller design

    Institute of Scientific and Technical Information of China (English)

    郭雷; 忻欣; 冯纯伯

    1997-01-01

    The design of reduced-order controllers is considered for stabilization control, covariance upper bound control, linear quadratic regulator, ∞ control, H∞ control, positive real control problems and robust H2 control, robust ∞ control and robust H∞ control problems for generalized linear plants without any additional assumptions. An upper bound of the order is obtained with which the (robust) controllers can guarantee stability constraints and satisfy the same design objectives as the so-called "full-order" controllers. A unified linear-matrix-inequality ( LMI) based approach to reduced-order (robust) controller design for all the above-mentioned problems is provided. It us shown that each of these problems is solvable if and only if two uncoupled LMIs with an LMI-type constraint have a pair of positive definite solutions, one of which has a lower dimension than that given by Skelton and iwasaki (1995). All desired reduced-order (robust) controllers are parameterized via the solutions of LMIs Moreov

  13. CONTROLLING TRAFFIC FLOW IN MULTILANE-ISOLATED INTERSECTION USING ANFIS APPROACH TECHNIQUES

    Directory of Open Access Journals (Sweden)

    G. R. LAI

    2015-08-01

    Full Text Available Many controllers have applied the Adaptive Neural-Fuzzy Inference System (ANFIS concept for optimizing the controller performance. However, there are less traffic signal controllers developed using the ANFIS concept. ANFIS traffic signal controller with its fuzzy rule base and its ability to learn from a set of sample data could improve the performance of Existing traffic signal controlling system to reduce traffic congestions at most of the busy traffic intersections in city such as Kuala Lumpur, Malaysia. The aim of this research is to develop an ANFIS traffic signals controller for multilane-isolated four approaches intersections in order to ease traffic congestions at traffic intersections. The new concept to generate sample data for ANFIS training is introduced in this research. The sample data is generated based on fuzzy rules and can be analysed using tree diagram. This controller is simulated on multilane-isolated traffic intersection model developed using M/M/1 queuing theory and its performance in terms of average waiting time, queue length and delay time are compared with traditional controllers and fuzzy controller. Simulation result shows that the average waiting time, queue length, and delay time of ANFIS traffic signal controller are the lowest as compared to the other three controllers. In conclusion, the efficiency and performance of ANFIS controller are much better than that of fuzzy and traditional controllers in different traffic volumes.

  14. Vehicle height and posture control of the electronic air suspension system using the hybrid system approach

    Science.gov (United States)

    Sun, Xiaoqiang; Cai, Yingfeng; Chen, Long; Liu, Yanling; Wang, Shaohua

    2016-03-01

    The electronic air suspension (EAS) system can improve ride comfort, fuel economy and handling safety of vehicles by adjusting vehicle height. This paper describes the development of a novel controller using the hybrid system approach to adjust the vehicle height (height control) and to regulate the roll and pitch angles of the vehicle body during the height adjustment process (posture control). The vehicle height adjustment system of EAS poses challenging hybrid control problems, since it features different discrete modes of operation, where each mode has an associated linear continuous-time dynamic. In this paper, we propose a novel approach to the modelling and controller design problem for the vehicle height adjustment system of EAS. The system model is described firstly in the hybrid system description language (HYSDEL) to obtain a mixed logical dynamical (MLD) hybrid model. For the resulting model, a hybrid model predictive controller is tuned to improve the vehicle height and posture tracking accuracy and to achieve the on-off statuses direct control of solenoid valves. The effectiveness and performance of the proposed approach are demonstrated by simulations and actual vehicle tests.

  15. Optimal control of open quantum systems: A combined surrogate Hamiltonian optimal control theory approach applied to photochemistry on surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Asplund, Erik; Kluener, Thorsten [Institut fuer Reine und Angewandte Chemie, Carl von Ossietzky Universitaet Oldenburg, Postfach 2503, D-26111 Oldenburg (Germany)

    2012-03-28

    In this paper, control of open quantum systems with emphasis on the control of surface photochemical reactions is presented. A quantum system in a condensed phase undergoes strong dissipative processes. From a theoretical viewpoint, it is important to model such processes in a rigorous way. In this work, the description of open quantum systems is realized within the surrogate Hamiltonian approach [R. Baer and R. Kosloff, J. Chem. Phys. 106, 8862 (1997)]. An efficient and accurate method to find control fields is optimal control theory (OCT) [W. Zhu, J. Botina, and H. Rabitz, J. Chem. Phys. 108, 1953 (1998); Y. Ohtsuki, G. Turinici, and H. Rabitz, J. Chem. Phys. 120, 5509 (2004)]. To gain control of open quantum systems, the surrogate Hamiltonian approach and OCT, with time-dependent targets, are combined. Three open quantum systems are investigated by the combined method, a harmonic oscillator immersed in an ohmic bath, CO adsorbed on a platinum surface, and NO adsorbed on a nickel oxide surface. Throughout this paper, atomic units, i.e., ({Dirac_h}/2{pi})=m{sub e}=e=a{sub 0}= 1, have been used unless otherwise stated.

  16. Comparative Study Between the Two Experimental Design Approaches Taguchi and Traditional in Presence of Control by Control Interactions

    Directory of Open Access Journals (Sweden)

    Arias-Nava Elías Heriberto

    2015-03-01

    Full Text Available Design of experiments plays an important role in the field of creating and innovating process and products directly in manufacturing and improving areas. There are several areas into designs of experiments; robust design is one of them. Robust parameter design is a principle that emphasize in products creation through a correct selection of values called “control” which make a product robust to the variability by the noise introducing by another factors known as “noise” factors. This article aims for a comparative study between two well-known robust design methodologies, making a special emphasis in the control by control interaction effects over optimal operating conditions. The results showed that Taguchi´s crossed arrays are unable to estimate all significant terms in a model. The optimizations result concludes that the Taguchi´s approach is less efficient than the traditional approach in both; maximization and minimization.

  17. Photon control by multi-periodic binary grating waveguides: A coupled-mode theory approach

    DEFF Research Database (Denmark)

    Adam, Jost; Lüder, Hannes; Gerken, Martina

    - taneous control over multiple spectral resonance positions and relative intensities. The experimental findings were theoretically backed up by a rigorous coupled-wave analysis (RCWA) approach, yielding the leaky modes’ complex propagation constants and diffraction efficiencies. This approach, however, can...... only lead to quantitative results outside the device’s band gaps, since only radiative propagation loss is calculated.n order to provide more physical and quantitative insight to grating-induced waveguide losses, we implemented a coupled-mode theory (CMT) approach for the semi-analytical treatment...

  18. Model Predictive Approach to Precision Contouring Control for Feed Drive Systems

    Directory of Open Access Journals (Sweden)

    A. E. M.

    2010-01-01

    Full Text Available Problem statement: High precision machining requires high capability of multi-axis feed drive systems to follow specified contour accurately. Although each feed drive axis is controlled independently in many industrial applications such as X-Y tables and Computer Numerical Control (CNC machines, machining precision is evaluated by error components orthogonal to desired contour curve. Contouring controller design is required for precision machining, which should consider disturbance and dynamics variation such as friction, cutting force and workpiece mass change. Approach: This study applied model predictive design to contouring control systems. Model predictive control utilized an explicit process model and tracking error dynamics to predict the future behavior of a plant and hence it is effective for precision machining in machine tool feed drives. To improve the contouring performance, a new performance index was proposed in which error components orthogonal to the desired contour curve are more important than tracking errors with respect to each feed drive axis. Controller parameters were calculated in real time by solving an optimization problem. Results: The proposed controller was evaluated by computer simulation for circular and non-circular trajectories. Weighting factors of performance index terms were used as tuning factors of the proposed controller. Simulation results showed that a better contouring performance can be obtained by choosing of the weighting factors in performance index items appropriately. Conclusion/Recommendations: A model predictive contouring controller for biaxial feed drive systems was presented. Simulation results demonstrated that the proposed approach can significantly improve the contouring accuracy.

  19. Motion control of planar parallel robot using the fuzzy descriptor system approach.

    Science.gov (United States)

    Vermeiren, Laurent; Dequidt, Antoine; Afroun, Mohamed; Guerra, Thierry-Marie

    2012-09-01

    This work presents the control of a two-degree of freedom parallel robot manipulator. A quasi-LPV approach, through the so-called TS fuzzy model and LMI constraints problems is used. Moreover, in this context a way to derive interesting control laws is to keep the descriptor form of the mechanical system. Therefore, new LMI problems have to be defined that helps to reduce the conservatism of the usual results. Some relaxations are also proposed to leave the pure quadratic stability/stabilization framework. A comparison study between the classical control strategies from robotics and the control design using TS fuzzy descriptor models is carried out to show the interest of the proposed approach. PMID:22633366

  20. Heteronanojunctions with atomic size control using a lab-on-chip electrochemical approach with integrated microfluidics

    Science.gov (United States)

    Lunca Popa, P.; Dalmas, G.; Faramarzi, V.; Dayen, J. F.; Majjad, H.; Kemp, N. T.; Doudin, B.

    2011-05-01

    A versatile tool for electrochemical fabrication of heteronanojunctions with nanocontacts made of a few atoms and nanogaps of molecular spacing is presented. By integrating microfluidic circuitry in a lab-on-chip approach, we keep control of the electrochemical environment in the vicinity of the nanojunction and add new versatility for exchanging and controlling the junction's medium. Nanocontacts made of various materials by successive local controlled depositions are demonstrated, with electrical properties revealing sizes reaching a few atoms only. Investigations on benchmark molecular electronics material, trapped between electrodes, reveal the possibility to create nanogaps of size matching those of molecules. We illustrate the interest of a microfluidic approach by showing that exposure of a fabricated molecular junction to controlled high solvent flows can be used as a reliability criterion for the presence of molecular entities in a gap.

  1. Heteronanojunctions with atomic size control using a lab-on-chip electrochemical approach with integrated microfluidics

    Energy Technology Data Exchange (ETDEWEB)

    Lunca Popa, P; Dalmas, G; Faramarzi, V; Dayen, J F; Majjad, H; Doudin, B [Institut de Physique et Chimie des Materiaux de Strasbourg, UMR 7504 CNRS-UdS, 23 rue du Loess, BP 43, 67034 Strasbourg (France); Kemp, N T, E-mail: petpo@ifm.liu.se, E-mail: bernard.doudin@ipcms.u-strasbg.fr [Department of Physics, University of Hull, Cottingham Road, Kingston-upon-Hull, HU6 7RX (United Kingdom)

    2011-05-27

    A versatile tool for electrochemical fabrication of heteronanojunctions with nanocontacts made of a few atoms and nanogaps of molecular spacing is presented. By integrating microfluidic circuitry in a lab-on-chip approach, we keep control of the electrochemical environment in the vicinity of the nanojunction and add new versatility for exchanging and controlling the junction's medium. Nanocontacts made of various materials by successive local controlled depositions are demonstrated, with electrical properties revealing sizes reaching a few atoms only. Investigations on benchmark molecular electronics material, trapped between electrodes, reveal the possibility to create nanogaps of size matching those of molecules. We illustrate the interest of a microfluidic approach by showing that exposure of a fabricated molecular junction to controlled high solvent flows can be used as a reliability criterion for the presence of molecular entities in a gap.

  2. Control of a Biped Robot by Total Rate of Angular Momentum Using the Task Function Approach

    Directory of Open Access Journals (Sweden)

    J. A. Rojas-Estrada

    2005-01-01

    Full Text Available In this work we address the control problem of biped robots by using the task function approach. A problem arrives when one of the feet is in contact with the ground, which presents imperfections. There is then the possibility that the biped robot undergoes a fall. It is difficult to track any trajectory due to the presence of unevenness on the ground. What we propose is to use the task function approach combined with the application of the total rate of angular momentum to obtain a control law for the ankle. By this technique, the tracking becomes more smooth and the balance is assured. The control law proposed allows the upper part of the robot to be controlled independently since only the ankle actuators are concerned. We enounce the formal problem and present some simulations with real parameters of a 21 degrees of freedom biped robot.

  3. Intelligent control a hybrid approach based on fuzzy logic, neural networks and genetic algorithms

    CERN Document Server

    Siddique, Nazmul

    2014-01-01

    Intelligent Control considers non-traditional modelling and control approaches to nonlinear systems. Fuzzy logic, neural networks and evolutionary computing techniques are the main tools used. The book presents a modular switching fuzzy logic controller where a PD-type fuzzy controller is executed first followed by a PI-type fuzzy controller thus improving the performance of the controller compared with a PID-type fuzzy controller.  The advantage of the switching-type fuzzy controller is that it uses one rule-base thus minimises the rule-base during execution. A single rule-base is developed by merging the membership functions for change of error of the PD-type controller and sum of error of the PI-type controller. Membership functions are then optimized using evolutionary algorithms. Since the two fuzzy controllers were executed in series, necessary further tuning of the differential and integral scaling factors of the controller is then performed. Neural-network-based tuning for the scaling parameters of t...

  4. An approach to predicting bowing control parameter contours in violin performance

    OpenAIRE

    Maestre E.; Ramirez R.

    2010-01-01

    We present a machine learning approach to modeling bowing control parameter contours in violin performance. Using accurate sensing techniques we obtain relevant timbre-related bowing control parameters such as bow transversal velocity, bow pressing force, and bow-bridge distance of each performed note. Each performed note is represented by a curve parameter vector and a number of note classes are defined. The principal components of the data represented by the set of curve p...

  5. Control and fault diagnosis based sliding mode observer of a multicellular converter: Hybrid approach

    KAUST Repository

    Benzineb, Omar

    2013-01-01

    In this article, the diagnosis of a three cell converter is developed. The hybrid nature of the system represented by the presence of continuous and discrete dynamics is taken into account in the control design. The idea is based on using a hybrid control and an observer-type sliding mode to generate residuals from the observation errors of the system. The simulation results are presented at the end to illustrate the performance of the proposed approach. © 2013 FEI STU.

  6. A Formal Approach for the Construction and Verification of Railway Control Systems

    DEFF Research Database (Denmark)

    Haxthausen, Anne Elisabeth; Peleska, Jan; Kinder, Sebastian

    2011-01-01

    This paper describes a complete model-based development and verification approach for railway control systems. For each control system to be generated, the user makes a description of the application-specific parameters in a domain-specific language. This description is automatically transformed ...... are verified for the SystemC model by means of bounded model checking. (2) The object code is verified to be I/O behaviourally equivalent to the SystemC model from which it was compiled....

  7. Expert Meeting: Recommended Approaches to Humidity Control in High Performance Homes

    Energy Technology Data Exchange (ETDEWEB)

    Rudd, A.

    2013-07-01

    The topic of this Building America expert meeting was 'Recommended Approaches to Humidity Control in High Performance Homes,' which was held on October 16, 2012, in Westford, MA, and brought together experts in the field of residential humidity control to address modeling issues for dehumidification. The presentations and discussions centered on computer simulation and field experience with these systems, with the goal of developing foundational information to support the development of a Building America Measure Guideline on this topic.

  8. Optimal speech motor control and token-to-token variability: a Bayesian modeling approach

    OpenAIRE

    Patri, Jean-François; Diard, Julien; Perrier, Pascal

    2015-01-01

    The remarkable capacity of the speech motor system to adapt to various speech conditions is due to an excess of degrees of freedom, which enables producing similar acoustical properties with different sets of control strategies. To explain how the Central Nervous System selects one of the possible strategies, a common approach, in line with optimal motor control theories, is to model speech motor planning as the solution of an optimality problem based on cost functions. Despite the success of...

  9. A Control Approach for Thrust-Propelled Underactuated Vehicles and its Application to VTOL Drones

    OpenAIRE

    Hua, Minh-Duc; Hamel, Tarek; Morin, Pascal; Samson, Claude

    2009-01-01

    A control approach is proposed for a class of underactuated vehicles in order to stabilize reference trajectories either in thrust direction, velocity, or position. The basic modeling assumption is that the vehicle is propulsed via a thrust force along a single body-fixed direction and that it has full torque actuation for attitude control (i.e., a typical actuation structure for aircrafts, Vertical Take-Off and Landing (VTOL) vehicles, submarines, etc.). Additional assumptions on the externa...

  10. Combined object-oriented approach for development of process control systems

    International Nuclear Information System (INIS)

    Full text: The traditional approaches for development of software control system in automation an information technology based on a directly code creation are no longer effective and successful enough. The response to these challenges is the Model Driven Engineering (MDE) or its counter part in the field of architectures Model Driven Architecture (MDA). One of the most promising approach supporting MDE and MDA is UML. It does not specify a methodology for software or system design but aims to provide an integrated modeling framework for structural, functional and behavior descriptions. The success of UML in many object-oriented approaches led to an idea of applying UML to design of multi agent systems. The approach proposed in this paper applies modified Harmony methodology and is based on the combined use of UML profile for system engineering, IEC61499 standard and FIPA standard protocols. The benefits of object-oriented paradigm and the models of IEC61499 standard are extended with UML/SysML and FIPA notations. The development phases are illustrated with the UML models of a simple process control system. The main benefits of using the proposed approach can be summarized as: it provides consistency in the syntax and underlying semantics; increases the potential and likelihood of reuse; supports the whole software development life cycle in the field of process control. Including the SysML features, based on extended activity and parametric diagrams, flow ports and items to the proposed approach opens the possibilities for modeling of continuous system and support the development in field of process control. Another advantage, connected to the UML/MARTE profile is the possibility for analysis of the designed system and detailed design of the hardware and software platform of the modeled application. Key words: object-oriented modeling, control system, UML, SysML, IEC 61499

  11. The consistency approach for quality control of vaccines - a strategy to improve quality control and implement 3Rs.

    Science.gov (United States)

    De Mattia, Fabrizio; Chapsal, Jean-Michel; Descamps, Johan; Halder, Marlies; Jarrett, Nicholas; Kross, Imke; Mortiaux, Frederic; Ponsar, Cecile; Redhead, Keith; McKelvie, Jo; Hendriksen, Coenraad

    2011-01-01

    Current batch release testing of established vaccines emphasizes quality control of the final product and is often characterized by extensive use of animals. This report summarises the discussions of a joint ECVAM/EPAA workshop on the applicability of the consistency approach for routine release of human and veterinary vaccines and its potential to reduce animal use. The consistency approach is based upon thorough characterization of the vaccine during development and the principle that the quality of subsequent batches is the consequence of the strict application of a quality system and of a consistent production of batches. The concept of consistency of production is state-of-the-art for new-generation vaccines, where batch release is mainly based on non-animal methods. There is now the opportunity to introduce the approach into established vaccine production, where it has the potential to replace in vivo tests with non-animal tests designed to demonstrate batch quality while maintaining the highest quality standards. The report indicates how this approach may be further developed for application to established human and veterinary vaccines and emphasizes the continuing need for co-ordination and harmonization. It also gives recommendations for work to be undertaken in order to encourage acceptance and implementation of the consistency approach.

  12. Approach to design of Nonlinear Robust Control in a Class of Structurally Stable Functions

    CERN Document Server

    Ten, Viktor

    2009-01-01

    An approach to stabilization of control systems with ultimately wide ranges of uncertainly disturbed parameters is offered. The method relies on using of nonlinear structurally stable functions from catastrophe theory as controllers. Analytical part presents an analysis of designed nonlinear second-order control systems. As more important the integrators in series, canonical controllable form and Jordan forms are considered. The analysis resumes that due to added controllers systems become stable and insensitive to any disturbance of parameters. Experimental part presents MATLAB simulation of design of possible control systems on the examples of epidemic spread, angular motion of aircraft and submarine depth. The results of simulation confirm the efficiency of offered method of design.

  13. Robust Adaptive Neural Sliding Mode Approach for Tracking Control of a MEMS Triaxial Gyroscope

    Directory of Open Access Journals (Sweden)

    Juntao Fei

    2012-05-01

    Full Text Available In this paper, a neural network adaptive sliding mode control is proposed for an MEMS triaxial gyroscope with unknown system nonlinearities. An input‐output linearization technique is incorporated into the neural adaptive tracking control to cancel the nonlinearities, and the neural network whose parameters are updated from the Lyapunov approach is used to perform the linearization control law. The sliding mode control is utilized to\tcompensate the neural network’s approximation errors. The stability of the closed‐loop system can be guaranteed with the proposed adaptive neural sliding mode control. Numerical simulations are investigated to verify the effectiveness of the proposed adaptive neural sliding mode control scheme.

  14. Application of Transfer Matrix Approach to Modeling and Decentralized Control of Lattice-Based Structures

    Science.gov (United States)

    Cramer, Nick; Swei, Sean Shan-Min; Cheung, Kenny; Teodorescu, Mircea

    2015-01-01

    This paper presents a modeling and control of aerostructure developed by lattice-based cellular materials/components. The proposed aerostructure concept leverages a building block strategy for lattice-based components which provide great adaptability to varying ight scenarios, the needs of which are essential for in- ight wing shaping control. A decentralized structural control design is proposed that utilizes discrete-time lumped mass transfer matrix method (DT-LM-TMM). The objective is to develop an e ective reduced order model through DT-LM-TMM that can be used to design a decentralized controller for the structural control of a wing. The proposed approach developed in this paper shows that, as far as the performance of overall structural system is concerned, the reduced order model can be as e ective as the full order model in designing an optimal stabilizing controller.

  15. Robust Active Disturbance Rejection Control Approach to Maximize Energy Capture in Variable-Speed Wind Turbines

    Directory of Open Access Journals (Sweden)

    Horacio Coral-Enriquez

    2013-01-01

    Full Text Available This paper proposes an alternative robust observer-based linear control technique to maximize energy capture in a 4.8 MW horizontal-axis variable-speed wind turbine. The proposed strategy uses a generalized proportional integral (GPI observer to reconstruct the aerodynamic torque in order to obtain a generator speed optimal trajectory. Then, a robust GPI observer-based controller supported by an active disturbance rejection (ADR approach allows asymptotic tracking of the generator speed optimal trajectory. The proposed methodology controls the power coefficient, via the generator angular speed, towards an optimum point at which power coefficient is maximum. Several simulations (including an actuator fault are performed on a 4.8 MW wind turbine benchmark model in order to validate the proposed control strategy and to compare it to a classical controller. Simulation and validation results show that the proposed control strategy is effective in terms of power capture and robustness.

  16. Periodic reference tracking control approach for smart material actuators with complex hysteretic characteristics

    Science.gov (United States)

    Sun, Zhiyong; Hao, Lina; Song, Bo; Yang, Ruiguo; Cao, Ruimin; Cheng, Yu

    2016-10-01

    Micro/nano positioning technologies have been attractive for decades for their various applications in both industrial and scientific fields. The actuators employed in these technologies are typically smart material actuators, which possess inherent hysteresis that may cause systems behave unexpectedly. Periodic reference tracking capability is fundamental for apparatuses such as scanning probe microscope, which employs smart material actuators to generate periodic scanning motion. However, traditional controller such as PID method cannot guarantee accurate fast periodic scanning motion. To tackle this problem and to conduct practical implementation in digital devices, this paper proposes a novel control method named discrete extended unparallel Prandtl-Ishlinskii model based internal model (d-EUPI-IM) control approach. To tackle modeling uncertainties, the robust d-EUPI-IM control approach is investigated, and the associated sufficient stabilizing conditions are derived. The advantages of the proposed controller are: it is designed and represented in discrete form, thus practical for digital devices implementation; the extended unparallel Prandtl-Ishlinskii model can precisely represent forward/inverse complex hysteretic characteristics, thus can reduce modeling uncertainties and benefits controllers design; in addition, the internal model principle based control module can be utilized as a natural oscillator for tackling periodic references tracking problem. The proposed controller was verified through comparative experiments on a piezoelectric actuator platform, and convincing results have been achieved.

  17. SimSup's Loop: A Control Theory Approach to Spacecraft Operator Training

    Science.gov (United States)

    Owens, Brandon Dewain; Crocker, Alan R.

    2015-01-01

    Immersive simulation is a staple of training for many complex system operators, including astronauts and ground operators of spacecraft. However, while much has been written about simulators, simulation facilities, and operator certification programs, the topic of how one develops simulation scenarios to train a spacecraft operator is relatively understated in the literature. In this paper, an approach is presented for using control theory as the basis for developing the immersive simulation scenarios for a spacecraft operator training program. The operator is effectively modeled as a high level controller of lower level hardware and software control loops that affect a select set of system state variables. Simulation scenarios are derived from a STAMP-based hazard analysis of the operator's high and low level control loops. The immersive simulation aspect of the overall training program is characterized by selecting a set of scenarios that expose the operator to the various inadequate control actions that stem from control flaws and inadequate control executions in the different sections of the typical control loop. Results from the application of this approach to the Lunar Atmosphere and Dust Environment Explorer (LADEE) mission are provided through an analysis of the simulation scenarios used for operator training and the actual anomalies that occurred during the mission. The simulation scenarios and inflight anomalies are mapped to specific control flaws and inadequate control executions in the different sections of the typical control loop to illustrate the characteristics of anomalies arising from the different sections of the typical control loop (and why it is important for operators to have exposure to these characteristics). Additionally, similarities between the simulation scenarios and inflight anomalies are highlighted to make the case that the simulation scenarios prepared the operators for the mission.

  18. Neural network approach to continuous-time direct adaptive optimal control for partially unknown nonlinear systems.

    Science.gov (United States)

    Vrabie, Draguna; Lewis, Frank

    2009-04-01

    In this paper we present in a continuous-time framework an online approach to direct adaptive optimal control with infinite horizon cost for nonlinear systems. The algorithm converges online to the optimal control solution without knowledge of the internal system dynamics. Closed-loop dynamic stability is guaranteed throughout. The algorithm is based on a reinforcement learning scheme, namely Policy Iterations, and makes use of neural networks, in an Actor/Critic structure, to parametrically represent the control policy and the performance of the control system. The two neural networks are trained to express the optimal controller and optimal cost function which describes the infinite horizon control performance. Convergence of the algorithm is proven under the realistic assumption that the two neural networks do not provide perfect representations for the nonlinear control and cost functions. The result is a hybrid control structure which involves a continuous-time controller and a supervisory adaptation structure which operates based on data sampled from the plant and from the continuous-time performance dynamics. Such control structure is unlike any standard form of controllers previously seen in the literature. Simulation results, obtained considering two second-order nonlinear systems, are provided. PMID:19362449

  19. A Controllability Approach for Resonant Compliant Systems: Applied to a Flapping Wing Micro Air Vehicle

    NARCIS (Netherlands)

    Peters, H.J.

    2016-01-01

    This thesis studies a controllability approach for general resonant compliant systems. These systems exploit resonance to obtain a specific dynamic response at relatively low actuation power. This type of systems is often lightweight, is scalable and minimizes frictional losses through the use of co

  20. Educating Masters of Public Health Students on Tobacco Control and Prevention: An Integrated Curriculum Approach

    Science.gov (United States)

    Lowe, John; Aquilino, Mary; Abramsohn, Erin

    2007-01-01

    Objectives: Comprehensive training in the area of tobacco control and prevention has not been available to public health students receiving professional degrees. This study describes findings of a project designed to develop and evaluate an integrated approach to the education of Masters of Public Health (MPH) students at the University of Iowa…

  1. Inventory control of spare parts using a Bayesian approach: a case study

    NARCIS (Netherlands)

    K-P. Aronis; I. Magou (Ioulia); R. Dekker (Rommert); G. Tagaras (George)

    1999-01-01

    textabstractThis paper presents a case study of applying a Bayesian approach to forecast demand and subsequently determine the appropriate parameter S of an (S-1,S) inventory system for controlling spare parts of electronic equipment. First, the problem and the current policy are described. Then, t

  2. Exercising Quality Control in Interdisciplinary Education: Toward an Epistemologically Responsible Approach

    Science.gov (United States)

    Stein, Zachary; Connell, Michael; Gardner, Howard

    2008-01-01

    This article argues that certain philosophically devised quality control parameters should guide approaches to interdisciplinary education. We sketch the kind of reflections we think are necessary in order to produce epistemologically responsible curricula. We suggest that the two overarching epistemic dimensions of levels of analysis and basic…

  3. Dataflow-based multi-ASIP platform approach for digital control applications

    NARCIS (Netherlands)

    Frijns, R.M.W.; Kamp, A.L.J.; Stuijk, S.; Voeten, J.P.M.; Bontekoe, M.; Gemei, K.J.A.; Corporaal, H.

    2013-01-01

    To provide a good balance between the performance and flexibility of future digital control platforms, we propose an FPGA-based heterogeneous multiprocessor approach, in which the platform is composed of processing elements from a set of parameterizable heterogeneous Application-Specific Instruction

  4. H(infinity) output tracking control for nonlinear systems via T-S fuzzy model approach.

    Science.gov (United States)

    Lin, Chong; Wang, Qing-Guo; Lee, Tong Heng

    2006-04-01

    This paper studies the problem of H(infinity) output tracking control for nonlinear time-delay systems using Takagi-Sugeno (T-S) fuzzy model approach. An LMI-based design method is proposed for achieving the output tracking purpose. Illustrative examples are given to show the effectiveness of the present results.

  5. Anger and Approach Motivation in Infancy: Relations to Early Childhood Inhibitory Control and Behavior Problems

    Science.gov (United States)

    He, Jie; Degnan, Kathryn Amey; McDermott, Jennifer Martin; Henderson, Heather A.; Hane, Amie Ashley; Xu, Qinmei; Fox, Nathan A.

    2010-01-01

    The relations among infant anger reactivity, approach behavior, and frontal electroencephalogram (EEG) asymmetry, and their relations to inhibitory control and behavior problems in early childhood were examined within the context of a longitudinal study of temperament. Two hundred nine infants' anger expressions to arm restraint were observed at 4…

  6. Food Control and a Citizen Science Approach for Improving Teaching of Genetics in Universities

    Science.gov (United States)

    Borrell, Y. J.; Muñoz-Colmenero, A. M.; Dopico, E.; Miralles, L.; Garcia-Vazquez, E.

    2016-01-01

    A Citizen Science approach was implemented in the laboratory practices of Genetics at the University of Oviedo, related with the engaging topic of Food Control. Real samples of food products consumed by students at home ("students as samplers") were employed as teaching material in three different courses of Genetics during the academic…

  7. ADVANZ – control of neglected zoonotic diseases using one health and ecohealth approaches

    DEFF Research Database (Denmark)

    Saarnak, Christopher; Mukaratirwa, S.; Johansen, Maria Vang

    , echinococcosis, and taeniasis/cysticercosis. Five other diseases have also been declared neglected, i.e. brucellosis, bovine tuberculosis, anthrax, human African trypanosomiasis, and leishmaniasis. The best strategic approach to transmission control and management of these diseases involves integrated One Health...

  8. Innovative Approaches for Urban Watershed Wet-Weather Flow Management and Control

    Science.gov (United States)

    The “Innovative Approaches for Urban Watershed Wet-Weather Flow Management and Control: State of the Technology” project investigated a range of innovative technology and management strategies emerging outside the normal realm of business within the continental United States, fo...

  9. Satisficing-Based Approach to Resolve Feature Interactions in Control Systems

    DEFF Research Database (Denmark)

    Sørensen, Jan Corfixen; Jørgensen, Bo Nørregaard

    2013-01-01

    problem. We demonstrate our approach in a real-life control system for industrial pot plant cultivation in greenhouses and show that solutions are found for compatible requirements and that conflicts are identified and explained for incompatible requirements. © 2013 Springer Science+Business Media....

  10. Group sequential control of overall toxicity incidents in clinical trials - non-Bayesian and Bayesian approaches.

    Science.gov (United States)

    Yu, Jihnhee; Hutson, Alan D; Siddiqui, Adnan H; Kedron, Mary A

    2016-02-01

    In some small clinical trials, toxicity is not a primary endpoint; however, it often has dire effects on patients' quality of life and is even life-threatening. For such clinical trials, rigorous control of the overall incidence of adverse events is desirable, while simultaneously collecting safety information. In this article, we propose group sequential toxicity monitoring strategies to control overall toxicity incidents below a certain level as opposed to performing hypothesis testing, which can be incorporated into an existing study design based on the primary endpoint. We consider two sequential methods: a non-Bayesian approach in which stopping rules are obtained based on the 'future' probability of an excessive toxicity rate; and a Bayesian adaptation modifying the proposed non-Bayesian approach, which can use the information obtained at interim analyses. Through an extensive Monte Carlo study, we show that the Bayesian approach often provides better control of the overall toxicity rate than the non-Bayesian approach. We also investigate adequate toxicity estimation after the studies. We demonstrate the applicability of our proposed methods in controlling the symptomatic intracranial hemorrhage rate for treating acute ischemic stroke patients.

  11. Controlled growth of silica-titania hybrid functional nanoparticles through a multistep microfluidic approach.

    Science.gov (United States)

    Shiba, K; Sugiyama, T; Takei, T; Yoshikawa, G

    2015-11-11

    Silica/titania-based functional nanoparticles were prepared through controlled nucleation of titania and subsequent encapsulation by silica through a multistep microfluidic approach, which was successfully applied to obtaining aminopropyl-functionalized silica/titania nanoparticles for a highly sensitive humidity sensor.

  12. Integrated anticipatory control of road networks: a game-theoretical approach

    NARCIS (Netherlands)

    Taale, H.

    2008-01-01

    In The Netherlands, dynamic traffic management is an important approach to minimise the negative effects of increasing congestion. Measures such as ramp metering and route infor-mation, but also conventional traffic signal control, are used for this. Traditionally, the focus in designing traffic con

  13. [An object-oriented intelligent engineering design approach for lake pollution control].

    Science.gov (United States)

    Zou, Rui; Zhou, Jing; Liu, Yong; Zhu, Xiang; Zhao, Lei; Yang, Ping-Jian; Guo, Huai-Cheng

    2013-03-01

    Regarding the shortage and deficiency of traditional lake pollution control engineering techniques, a new lake pollution control engineering approach was proposed in this study, based on object-oriented intelligent design (OOID) from the perspective of intelligence. It can provide a new methodology and framework for effectively controlling lake pollution and improving water quality. The differences between the traditional engineering techniques and the OOID approach were compared. The key points for OOID were described as object perspective, cause and effect foundation, set points into surface, and temporal and spatial optimization. The blue algae control in lake was taken as an example in this study. The effect of algae control and water quality improvement were analyzed in details from the perspective of object-oriented intelligent design based on two engineering techniques (vertical hydrodynamic mixer and pumping algaecide recharge). The modeling results showed that the traditional engineering design paradigm cannot provide scientific and effective guidance for engineering design and decision-making regarding lake pollution. Intelligent design approach is based on the object perspective and quantitative causal analysis in this case. This approach identified that the efficiency of mixers was much higher than pumps in achieving the goal of low to moderate water quality improvement. However, when the objective of water quality exceeded a certain value (such as the control objective of peak Chla concentration exceeded 100 microg x L(-1) in this experimental water), the mixer cannot achieve this goal. The pump technique can achieve the goal but with higher cost. The efficiency of combining the two techniques was higher than using one of the two techniques alone. Moreover, the quantitative scale control of the two engineering techniques has a significant impact on the actual project benefits and costs.

  14. Inexact fuzzy integer chance constraint programming approach for noise control within an urban environment

    Science.gov (United States)

    Huang, Kai; Huang, Gordon; Dai, Liming; Fan, Yurui

    2016-08-01

    This article introduces an inexact fuzzy integer chance constraint programming (IFICCP) approach for identifying noise reduction strategy under uncertainty. The IFICCP method integrates the interval programming and fuzzy chance constraint programming approaches into a framework, which is able to deal with uncertainties expressed as intervals and fuzziness. The proposed IFICCP model can be converted into two deterministic submodels corresponding to the optimistic and pessimistic conditions. The modelling approach is applied to a hypothetical control measure selection problem for noise reduction. Results of the case study indicate that useful solutions for noise control practices can be acquired. Three acceptable noise levels for two communities are considered. For each acceptable noise level, several decision alternatives have been obtained and analysed under different fuzzy confidence levels, which reflect the trade-offs between environmental and economic considerations.

  15. An agent-based negotiation approach for balancing multiple coupled control domains

    DEFF Research Database (Denmark)

    Umair, Aisha; Clausen, Anders; Jørgensen, Bo Nørregaard

    2015-01-01

    Solving multi-objective multi-issue negotiation problems involving interdependent issues distributed among multiple control domains is inherent to most non-trivial cyber-physical systems. In these systems, the coordinated operation of interconnected subsystems performing autonomous control...... is essential to achieve overall system goals. In spite of its importance, the area has received limited attention to date. In this paper, we propose an innovative agent-based coordination approach for coordinating and controlling interconnected subsystems in cyber-physical systems with interdependent issues...

  16. ADAPTIVE CONTROL APPROACH FOR PERIODIC RATE RIPPLES IN INERTIAL GUIDANCE TEST EQUIPMENT

    Institute of Scientific and Technical Information of China (English)

    XUGuo-zhu; LIUYue; ZHANGYuan-sheng

    2005-01-01

    The rate performance of inertial guidance test equipment (IGTE) affects the performance testing of inertia devices and navigation systems. Periodic rate ripples caused by periodic disturbances have a great effect on the rate performance of rotation test tables. The mechanism caused by the rate ripple in IGTE is analyzed. Based on the nonlinear self-adaptive control system approach, a control system scheme is proposed to eliminate the period disturbances for its uncertainty. Experimental results show that the periodic rate ripple can efficiently be controlled.

  17. An effective access control approach to support mobility in IPv6 networks

    Science.gov (United States)

    Peng, Xue-hai; Lin, Chuang

    2005-11-01

    Access control is an important method to improve network security and prevent protected resources from being used by some nodes without authority. Moreover, mobility is an important trend of internet. In this paper, based on the architecture of hierarchical mobile IPv6, we proposed an effective access control approach to support mobility in IPv6 networks, which can ensure the operation of access control when a mobile node roams in these domains with different polices, with decreased delay of access negotiation and cost of delivering messages.

  18. A new approach to the Pontryagin maximum principle for nonlinear fractional optimal control problems

    Science.gov (United States)

    Ali, Hegagi M.; Pereira, Fernando Lobo; Gama, Sílvio M. A.

    2016-09-01

    In this paper, we discuss a new general formulation of fractional optimal control problems whose performance index is in the fractional integral form and the dynamics are given by a set of fractional differential equations in the Caputo sense. We use a new approach to prove necessary conditions of optimality in the form of Pontryagin maximum principle for fractional nonlinear optimal control problems. Moreover, a new method based on a generalization of the Mittag-Leffler function is used to solving this class of fractional optimal control problems. A simple example is provided to illustrate the effectiveness of our main result.

  19. Case-control design as investigative approach to assessing cancer etiology: development and future perspectives.

    Science.gov (United States)

    Kocic, B; Filipovic, S; Petrovic, B; Nikolic, M

    2012-01-01

    The case-control method evolved out of analyses of series of cases. The analytic form of the case-control study can be found in the 19th century medical literature, but did not appear to be viewed as a special or distinct methodology. The first modern case-control study was the Janet Lane-Claypon's study of breast cancer in 1926, but the design was used only sporadically in medicine until 1950, when 4 published casecontrol studies linked smoking and lung cancer. These 1950s studies synthesized the essential elements of the case-control comparison, produced a conceptual shift within epidemiology, and laid the foundation for the rapid development of the case-control design in the subsequent half century. The powerful consistency of these case-control studies, and the replication of their findings in later prospective studies, promoted the general acceptance of the case-control study as a scientific tool in clinical research. Newer case-control studies have benefited from the advances in design, execution and analysis since 1950s. These advances include more rigorous selection and matching of case and control population, improved interviewing techniques, location of the design within a general framework of epidemiologic strategies for relating exposure to disease, understanding of the measures of effect, and application of increasingly sophisticated statistical procedures to findings. This review traces the development and future perspectives of the case-control design to assessing cancer etiology. With illustrations drawn primarily from the literature on its use and the value of its results to unravelling the etiology of malignant diseases, we tried to explore if the case-control approach firmly ensconced in epidemiology as investigational tool and rivals in importance the more straightforward cohort approach. PMID:23033277

  20. LMI–based robust controller design approach in aircraft multidisciplinary design optimization problem

    Directory of Open Access Journals (Sweden)

    Qinghua Zeng

    2015-07-01

    Full Text Available This article proposes a linear matrix inequality–based robust controller design approach to implement the synchronous design of aircraft control discipline and other disciplines, in which the variation in design parameters is treated as equivalent perturbations. Considering the complicated mapping relationships between the coefficient arrays of aircraft motion model and the aircraft design parameters, the robust controller designed is directly based on the variation in these coefficient arrays so conservative that the multidisciplinary design optimization problem would be too difficult to solve, or even if there is a solution, the robustness of design result is generally poor. Therefore, this article derives the uncertainty model of disciplinary design parameters based on response surface approximation, converts the design problem of the robust controller into a problem of solving a standard linear matrix inequality, and theoretically gives a less conservative design method of the robust controller which is based on the variation in design parameters. Furthermore, the concurrent subspace approach is applied to the multidisciplinary system with this kind of robust controller in the design loop. A multidisciplinary design optimization of a tailless aircraft as example is shown that control discipline can be synchronous optimal design with other discipline, especially this method will greatly reduce the calculated amount of multidisciplinary design optimization and make multidisciplinary design optimization results more robustness of flight performance.

  1. A Comparison of Model Reduction Approaches for Feedback Control Design of Thermal Flows in Buildings

    Science.gov (United States)

    Borggaard, Jeff; Ahuja, Sunil; Burns, John; Cliff, Eugene; Surana, Amit

    2010-11-01

    The application of distributed parameter control to spatiotemporal thermo-fluid systems requires the use of model reduction methods. The form of the optimal feedback control can inform design decisions, such as sensor and actuator selection and placement. A number of model reduction approaches for fluid systems have been put forward that are based on the proper orthogonal decomposition (POD). In this talk, we examine three approaches, the traditional POD-Galerkin model, the POD-Sensitivity model, and the Balanced-POD models. Our work is motivated by the building indoor environment control problem. Energy performance in building cooling and heating systems can be substantially improved by exploiting spatial temperature stratification and buoyancy that are prevalent in passive systems. We consider the control of airflow in a room with a passively cooled radiant ceiling and displacement ventilation provided near the room floor. For this problem, we approximate the full-order solution to compute the control gains, develop reduced-order models and associated controllers, and simulate the full-order closed-loop system for comparison with the reduced-order model-based control design.

  2. Computationally inexpensive approach for pitch control of offshore wind turbine on barge floating platform.

    Science.gov (United States)

    Zuo, Shan; Song, Y D; Wang, Lei; Song, Qing-wang

    2013-01-01

    Offshore floating wind turbine (OFWT) has gained increasing attention during the past decade because of the offshore high-quality wind power and complex load environment. The control system is a tradeoff between power tracking and fatigue load reduction in the above-rated wind speed area. In allusion to the external disturbances and uncertain system parameters of OFWT due to the proximity to load centers and strong wave coupling, this paper proposes a computationally inexpensive robust adaptive control approach with memory-based compensation for blade pitch control. The method is tested and compared with a baseline controller and a conventional individual blade pitch controller with the "NREL offshore 5 MW baseline wind turbine" being mounted on a barge platform run on FAST and Matlab/Simulink, operating in the above-rated condition. It is shown that the advanced control approach is not only robust to complex wind and wave disturbances but adaptive to varying and uncertain system parameters as well. The simulation results demonstrate that the proposed method performs better in reducing power fluctuations, fatigue loads and platform vibration as compared to the conventional individual blade pitch control.

  3. Control of Thermo-Acoustics Instabilities: The Multi-Scale Extended Kalman Approach

    Science.gov (United States)

    Le, Dzu K.; DeLaat, John C.; Chang, Clarence T.

    2003-01-01

    "Multi-Scale Extended Kalman" (MSEK) is a novel model-based control approach recently found to be effective for suppressing combustion instabilities in gas turbines. A control law formulated in this approach for fuel modulation demonstrated steady suppression of a high-frequency combustion instability (less than 500Hz) in a liquid-fuel combustion test rig under engine-realistic conditions. To make-up for severe transport-delays on control effect, the MSEK controller combines a wavelet -like Multi-Scale analysis and an Extended Kalman Observer to predict the thermo-acoustic states of combustion pressure perturbations. The commanded fuel modulation is composed of a damper action based on the predicted states, and a tones suppression action based on the Multi-Scale estimation of thermal excitations and other transient disturbances. The controller performs automatic adjustments of the gain and phase of these actions to minimize the Time-Scale Averaged Variances of the pressures inside the combustion zone and upstream of the injector. The successful demonstration of Active Combustion Control with this MSEK controller completed an important NASA milestone for the current research in advanced combustion technologies.

  4. Computationally Inexpensive Approach for Pitch Control of Offshore Wind Turbine on Barge Floating Platform

    Directory of Open Access Journals (Sweden)

    Shan Zuo

    2013-01-01

    Full Text Available Offshore floating wind turbine (OFWT has gained increasing attention during the past decade because of the offshore high-quality wind power and complex load environment. The control system is a tradeoff between power tracking and fatigue load reduction in the above-rated wind speed area. In allusion to the external disturbances and uncertain system parameters of OFWT due to the proximity to load centers and strong wave coupling, this paper proposes a computationally inexpensive robust adaptive control approach with memory-based compensation for blade pitch control. The method is tested and compared with a baseline controller and a conventional individual blade pitch controller with the “NREL offshore 5 MW baseline wind turbine” being mounted on a barge platform run on FAST and Matlab/Simulink, operating in the above-rated condition. It is shown that the advanced control approach is not only robust to complex wind and wave disturbances but adaptive to varying and uncertain system parameters as well. The simulation results demonstrate that the proposed method performs better in reducing power fluctuations, fatigue loads and platform vibration as compared to the conventional individual blade pitch control.

  5. Potential International Approaches to Ownership/Control of Human Genetic Resources.

    Science.gov (United States)

    Rhodes, Catherine

    2016-09-01

    In its governance activities for genetic resources, the international community has adopted various approaches to their ownership, including: free access; common heritage of mankind; intellectual property rights; and state sovereign rights. They have also created systems which combine elements of these approaches. While governance of plant and animal genetic resources is well-established internationally, there has not yet been a clear approach selected for human genetic resources. Based on assessment of the goals which international governance of human genetic resources ought to serve, and the implications for how they will be accessed and utilised, it is argued that common heritage of mankind will be the most appropriate approach to adopt to their ownership/control. It does this with the aim of stimulating discussion in this area and providing a starting point for deeper consideration of how a common heritage of mankind, or similar, regime for human genetic resources would function and be implemented.

  6. Potential International Approaches to Ownership/Control of Human Genetic Resources.

    Science.gov (United States)

    Rhodes, Catherine

    2016-09-01

    In its governance activities for genetic resources, the international community has adopted various approaches to their ownership, including: free access; common heritage of mankind; intellectual property rights; and state sovereign rights. They have also created systems which combine elements of these approaches. While governance of plant and animal genetic resources is well-established internationally, there has not yet been a clear approach selected for human genetic resources. Based on assessment of the goals which international governance of human genetic resources ought to serve, and the implications for how they will be accessed and utilised, it is argued that common heritage of mankind will be the most appropriate approach to adopt to their ownership/control. It does this with the aim of stimulating discussion in this area and providing a starting point for deeper consideration of how a common heritage of mankind, or similar, regime for human genetic resources would function and be implemented. PMID:26297608

  7. FLOATING GASTRO-RETENTIVE DOSAGE FORMS - A NOVEL APPROACH FOR TARGETED AND CONTROLLED DRUG DELIVERY

    Directory of Open Access Journals (Sweden)

    Aleksandar Aleksovski

    2012-04-01

    Full Text Available Controlled (modified release dosage forms are one of the key concepts in drug delivery, leading to enhanced drug bioavailability and increased patient’s compliance. However conventional modified release dosage forms encounter one big disadvantage- lack of site-specific drug delivery. Scientists developed different kinds of targeted oral controlled release forms. One of these are gastro-retentive systems- systems which can remain in the stomach region for prolonged period of time and thereby release the active compound in controlled fashion. Floating dosage forms are the most promising approach of all gastro-retentive systems. They are capable to float over the gastric content in longer time intervals. This article makes a review on floating dosage forms in general, different approaches for achieving flotation, advantages and disadvantages of this drug delivery concept. For better understanding the topic,an emphasis is made also on the anatomical and physiological features of the stomach and on the factors affecting gastric retention.

  8. An Optimal Control Approach for an Overall Cryogenic Plant Under Pulsed Heat Loads

    CERN Document Server

    Gómez Palacin, Luis; Blanco Viñuela, Enrique; Maekawa, Ryuji; Chalifour, Michel

    2015-01-01

    This work deals with the optimal management of a cryogenic plant composed by parallel refrigeration plants, which provide supercritical helium to pulsed heat loads. First, a data reconciliation approach is proposed to estimate precisely the refrigerator variables necessary to deduce the efficiency of each refrigerator. Second, taking into account these efficiencies, an optimal operation of the system is proposed and studied. Finally, while minimizing the power consumption of the refrigerators, the control system maintains stable operation of the cryoplant under pulsed heat loads. The management of the refrigerators is carried out by an upper control layer, which balances the relative production of cooling power in each refrigerator. In addition, this upper control layer deals with the mitigation of malfunctions and faults in the system. The proposed approach has been validated using a dynamic model of the cryoplant developed with EcosimPro software, based on first principles (mass and energy balances) and the...

  9. Validating a centralized approach to primary frequency control with series-produced electric vehicles

    DEFF Research Database (Denmark)

    Marinelli, Mattia; Martinenas, Sergejus; Knezovic, Katarina;

    2016-01-01

    The aim of this work is twofold: on one hand it proposes a centralized approach to primary frequency control by using electric vehicles as controllable units; on the other hand, it experimentally validates whether series-produced EVs, adhering to contemporary standards, can be an effective resource...... for providing primary frequency control. The validation process is realized in an islanded system with renewable sources and it relies on verifying that the frequency values are within the desired limits following severe load steps or wind power fluctuations. In order to reflect today’s situation, the used EVs......, three Nissan Leaf, are not taking advantage of any V2G capability, but rely solely on the possibility of limiting the charge between 6 A and 16 A. The centralized approach implies that the frequency is not measured locally as it is a common practice today, but is routed via the Internet in order...

  10. A novel harmonic control approach of distributed generation converters in a weak microgrid

    DEFF Research Database (Denmark)

    Ding, Guangqian; Gao, Feng; Tang, Yi;

    2014-01-01

    converter output voltage, DG line current and line impedance. A voltage closed-loop controller and a current closed-loop controller are designed to achieve both functions of DG real power generation and PCC harmonics compensation. Therefore, the traditional harmonic measurement devices installed at the PCC......This paper proposes a novel approach to compensate the voltage at the point of common coupling (PCC) and the grid line current harmonics through a distributed generation (DG) interfacing converter in a weak microgrid. In the proposed approach, the PCC voltage is indirectly derived from the measured...... as well as the long distance communication between the PCC and the converter are fully eliminated. In order to avoid overcompensation, a harmonic current limitation algorithm is implemented in the control loop. bBy properly dispatching the harmonic compensation capability, multiple DG unites can...

  11. Fuzzy Saturated Output Feedback Tracking Control for Robot Manipulators: A Singular Perturbation Theory Based Approach

    Directory of Open Access Journals (Sweden)

    Huashan Liu

    2011-09-01

    Full Text Available To deal with the problem of the output feedback tracking (OFT control with bounded torque inputs of robot manipulators, we propose a generalized fuzzy saturated OFT controller based on singular perturbation theory. First, considering the fact that the output toque of joint actuators is limited, a general expression for a class of saturation functions is given to be applied in the control law. Second, to carry out the whole closed‐loop control with only position measurements, linear and nonlinear filters are optionally involved to generate a pseudo signal to surrogate the actual velocity tracking error. As a third contribution, a fuzzy regulator is added to obtain a self‐tuning performance in tackling the disturbances. Moreover, an explicit but strict stability proof of the system based on the stability theory of singularly perturbed systems is presented. Finally, numerical simulations on several sample controllers are implemented to verify the effectiveness of the proposed approach.

  12. A Unified Approach to Nonlinear Dynamic Inversion Control with Parameter Determination by Eigenvalue Assignment

    Directory of Open Access Journals (Sweden)

    Yu-Chi Wang

    2015-01-01

    Full Text Available This paper presents a unified approach to nonlinear dynamic inversion control algorithm with the parameters for desired dynamics determined by using an eigenvalue assignment method, which may be applied in a very straightforward and convenient way. By using this method, it is not necessary to transform the nonlinear equations into linear equations by feedback linearization before beginning control designs. The applications of this method are not limited to affine nonlinear control systems or limited to minimum phase problems if the eigenvalues of error dynamics are carefully assigned so that the desired dynamics is stable. The control design by using this method is shown to be robust to modeling uncertainties. To validate the theory, the design of a UAV control system is presented as an example. Numerical simulations show the performance of the design to be quite remarkable.

  13. Robust control of nonlinear MAGLEV suspension system with mismatched uncertainties via DOBC approach.

    Science.gov (United States)

    Yang, Jun; Zolotas, Argyrios; Chen, Wen-Hua; Michail, Konstantinos; Li, Shihua

    2011-07-01

    Robust control of a class of uncertain systems that have disturbances and uncertainties not satisfying "matching" condition is investigated in this paper via a disturbance observer based control (DOBC) approach. In the context of this paper, "matched" disturbances/uncertainties stand for the disturbances/uncertainties entering the system through the same channels as control inputs. By properly designing a disturbance compensation gain, a novel composite controller is proposed to counteract the "mismatched" lumped disturbances from the output channels. The proposed method significantly extends the applicability of the DOBC methods. Rigorous stability analysis of the closed-loop system with the proposed method is established under mild assumptions. The proposed method is applied to a nonlinear MAGnetic LEViation (MAGLEV) suspension system. Simulation shows that compared to the widely used integral control method, the proposed method provides significantly improved disturbance rejection and robustness against load variation. PMID:21349514

  14. A New Approach to Diagnosing Signals from Multivariate EWMA Control Chart

    Institute of Scientific and Technical Information of China (English)

    MA Yi-zhong; ZHAO Feng-yu

    2003-01-01

    Since Lowry et al. [1992] proposed a multivariate version of the exponentially weighted moving average (EWMA) control chart, the multivariate EWMA control chart has become more and more popular in monitoring production processes, especially in chemical processes. A major advantage of multivariate EWMA statistics is that it is sensitive to small and moderate shifts in the mean vector. However, when a multivariate EWMA chart issues a signal, it is difficult to identify which variable or set of variables is out of control. In this paper, we introduce a new approach to diagnosing signals from a multivariate EWMA control chart. The implementation procedure is that when the multivariate EWMA control chart issues a signal, we adopt a univariate diagnostic procedure to identify the variables or/and the principal components that caused the signal.

  15. Novel fuzzy feedback linearization strategy for control via differential geometry approach.

    Science.gov (United States)

    Li, Tzuu-Hseng S; Huang, Chiou-Jye; Chen, Chung-Cheng

    2010-07-01

    The study investigates a novel fuzzy feedback linearization strategy for control. The main contributions of this study are to construct a control strategy such that the resulting closed-loop system is valid for any initial condition with almost disturbance decoupling performance, and develop the feedback linearization design for some class of nonlinear control systems. The feedback linearization control guarantees the almost disturbance decoupling performance and the uniform ultimate bounded stability of the tracking error system. Once the tracking errors are driven to touch the global final attractor with the desired radius, the fuzzy logic control is immediately applied via a human expert's knowledge to improve the convergence rate. One example, which cannot be solved by the first paper on the almost disturbance decoupling problem, is proposed in this paper to exploit the fact that the almost disturbance decoupling and the convergence rate performances are easily achieved by the proposed approach.

  16. A novel integrated renewable energy system modelling approach, allowing fast FPGA controller prototyping

    DEFF Research Database (Denmark)

    Teodorescu, Remus; Ruiz, Alberto Parera; Cirstea, Marcian;

    2008-01-01

    for comparison. Later on, the model was successfully developed in Handel-C. The holistic functional simulation of the system is performed in the same environment as its controller hardware implementation and timing analysis. The controller design was then downloaded in hardware onto a RC100 development board...... containing a Xilinx Spartan II FPGA and was successfully experimentally tested. This approach enables the design and fast hardware implementation of efficient controllers for Distributed Energy Resource (DER) hybrid systems....... of a photovoltaic energy system and a wind power system, which would allow an optimized holistic digital control system design, followed by rapid prototyping of the controller into a single Field Programmable Gate Array (FPGA). Initially, the system was simulated using Matlab / Simulink, to create a reference...

  17. Approach for Autonomous Control of Unmanned Aerial Vehicle Using Intelligent Agents for Knowledge Creation

    Science.gov (United States)

    Dufrene, Warren R., Jr.

    2004-01-01

    This paper describes the development of a planned approach for Autonomous operation of an Unmanned Aerial Vehicle (UAV). A Hybrid approach will seek to provide Knowledge Generation through the application of Artificial Intelligence (AI) and Intelligent Agents (IA) for UAV control. The applications of several different types of AI techniques for flight are explored during this research effort. The research concentration is directed to the application of different AI methods within the UAV arena. By evaluating AI and biological system approaches. which include Expert Systems, Neural Networks. Intelligent Agents, Fuzzy Logic, and Complex Adaptive Systems, a new insight may be gained into the benefits of AI and CAS techniques applied to achieving true autonomous operation of these systems. Although flight systems were explored, the benefits should apply to many Unmanned Vehicles such as: Rovers. Ocean Explorers, Robots, and autonomous operation systems. A portion of the flight system is broken down into control agents that represent the intelligent agent approach used in AI. After the completion of a successful approach, a framework for applying an intelligent agent is presented. The initial results from simulation of a security agent for communication are presented.

  18. A wavelet approach for active-passive vibration control of laminated plates

    Institute of Scientific and Technical Information of China (English)

    Ji-Zeng Wang; Xiao-Min Wang; You-He Zhou

    2012-01-01

    As an extension of the wavelet approach to vibration control of piezoelectric beam-type plates developed earlier by the authors,this paper proposes a hybrid activepassive control strategy for suppressing vibrations of laminated rectangular plates bonded with distributed piezoelectric sensors and actuators via thin viscoelastic bonding layers.Owing to the low-pass filtering property of scaling function transform in orthogonal wavelet theory,this waveletbased control method has the ability to automatically filter out noise-like signal in the feedback control loop,hence reducing the risk of residual coupling effects which are usually the source of spillover instability.Moreover,the existence of thin viscoelastic bonding layers can further improve robustness and reliability of the system through dissipating the energy of any other possible noise induced partially by numerical errors during the control process.A simulation procedure based on an advanced wavelet-Galerkin technique is suggested to realize the hybrid active-passive control process.Numerical results demonstrate the efficiency of the proposed approach.

  19. NEW APPROACH FOR MEASUREMENT OF THE EFFICIENCY OF Cpm AND Cpmk CONTROL CHARTS

    Directory of Open Access Journals (Sweden)

    María Teresa Carot

    2013-12-01

    Full Text Available Process capability analysis is a very effective way for improving process quality by relating process variation to customer requirements. It compares the output of a process to the specification limits by using process capability indices (PCIs. PCIs provide numerical measures on whether aprocess conforms to the defined manufacturing capability prerequisite. In this paper, a new approach based on non-central Chi-Square, ω and φ distributions is presented to design the capability control charts. The main purpose of this work is to investigate the efficiency of the proposed control charts comparing with the traditional control charts. The advantage of using the proposed capability control charts is that, the practitioner can monitor the process mean and the process variability by looking at one chart. Moreover the proposed capability control charts are easily appended to X-R control chart and provide judgments considering the ability of a process to meet requirements. To demonstrate the applicability of the proposed approach an illustrative example is conducted.

  20. An Adaptive Approach for Multi-Agent Formation Control in MANET Based on CPS Perspective

    Directory of Open Access Journals (Sweden)

    Jinzhi Lin

    2014-05-01

    Full Text Available From Cyber Physical System (CPS perspective, it is nature for the system to tightly couple the communications and computing aspects with its physical dynamics. In this paper, we investigate this characteristic for multi-agent formation control in Mobile Ad-hoc Network (MANET. We manage to measure the real time wireless network congestion, implement a wireless QoS mechanism to provide different network channel access priorities and come up with the emergency calculation. Based on these, we present our adaptive approach for formation control. To examine the benefit of our approach, we use a co-simulation tool that we have developed for evaluating networked control & cyber physical system to study a specific scenario, in which five follower agents plus one leader perform a specific formation within a MANET with different congestion conditions. Through simulation experiments, it is showed that our approach could adaptively adjust sample periods and network channel access priorities according to real time dynamics emergencies and the network traffics condition, so as to optimize network utilization and improve the formation control performance

  1. Controlled-Source Electromagnetic Approaches for Hydrocarbon Exploration and Monitoring on Land

    Science.gov (United States)

    Streich, Rita

    2016-01-01

    Electromagnetic methods that utilize controlled sources have been applied for natural resource exploration for more than a century. Nevertheless, concomitant with the recent adoption of marine controlled-source electromagnetics (CSEM) by the hydrocarbon industry, the overall usefulness of CSEM methods on land has been questioned within the industry. Truly, there are few published examples of land CSEM surveys carried out completely analogously to the current marine CSEM standard approach of towing a bipole source across an array of stationary receivers, continuously transmitting a low-frequency signal and interpreting the data in the frequency domain. Rather, different sensitivity properties of different exploration targets in diverse geological settings, gradual advances in theoretical understanding, acquisition and computer technology, and different schools in different parts of the world have resulted in a sometimes confusing multitude of land-based controlled-source EM surveying approaches. Here, I aim to review previous and present-day approaches, and provide reasoning for their diversity. I focus on surface-based techniques while excluding airborne EM and well logging and on applications for hydrocarbon exploration. Attempts at the very demanding task of using onshore controlled-source EM for reservoir monitoring are shown, and the possible future potential of EM monitoring is discussed.

  2. Cyber Physical Systems: A New Approach to Power Electronics Simulation, Control and Testing

    Directory of Open Access Journals (Sweden)

    CELANOVIC, N. L.

    2012-02-01

    Full Text Available This paper presents a Cyber Physical Systems approach to power electronics simulation, control and testing. We present a new framework based on generalized hybrid automaton and application specific ultra-low latency high-speed processor architecture that enables high fidelity real-time power electronics model computation. To illustrate the performance of this approach we experimentally demonstrate two extremely computationally demanding power electronics applications: real-time emulation for Hardware-in-the-Loop (HIL testing, and hybrid system observers for fault detection and isolation.

  3. Regulating Response Time in an Autonomic Computing System: A Comparison of Proportional Control and Fuzzy Control Approaches

    Directory of Open Access Journals (Sweden)

    Harish S. Venkatarama

    2010-10-01

    Full Text Available Ecommerce is an area where an Autonomic Computing system could be very effectively deployed. Ecommerce has created demand for high quality information technology services and businesses are seeking quality of service guarantees from their service providers. These guarantees are expressed as part of service level agreements. Properly adjusting tuning parameters for enforcement of the service level agreement is time-consuming and skills-intensive. Moreover, in case of changes to the workload, the setting of the parameters may no longer be optimum. In an ecommerce system, where the workload changes frequently, there is a need to update the parameters at regular intervals. This paper describes two approaches, one, using a proportional controller and two, using a fuzzy controller, to automate the tuning of MaxClients parameter of Apache web server based on the required response time and the current workload. This is an illustration of the self-optimizing characteristic of an autonomic computing system.

  4. Regulating Response Time in an Autonomic Computing System: A Comparison of Proportional Control and Fuzzy Control Approaches

    Directory of Open Access Journals (Sweden)

    Harish S. Venkatarama

    2010-10-01

    Full Text Available Ecommerce is an area where an Autonomic Computing system could be very effectively deployed.Ecommerce has created demand for high quality information technology services and businesses areseeking quality of service guarantees from their service providers. These guarantees are expressed aspart of service level agreements. Properly adjusting tuning parameters for enforcement of the servicelevel agreement is time-consuming and skills-intensive. Moreover, in case of changes to the workload, thesetting of the parameters may no longer be optimum. In an ecommerce system, where the workloadchanges frequently, there is a need to update the parameters at regular intervals. This paper describestwo approaches, one, using a proportional controller and two, using a fuzzy controller, to automate thetuning of MaxClients parameter of Apache web server based on the required response time and thecurrent workload. This is an illustration of the self-optimizing characteristic of an autonomic computingsystem.

  5. Avoid, Control, Succumb, or Balance: Engineering Students' Approaches to a Wicked Sustainability Problem

    Science.gov (United States)

    Lönngren, Johanna; Ingerman, Åke; Svanström, Magdalena

    2016-07-01

    Wicked sustainability problems (WSPs) are an important and particularly challenging type of problem. Science and engineering education can play an important role in preparing students to deal with such problems, but current educational practice may not adequately prepare students to do so. We address this gap by providing insights related to students' abilities to address WSPs. Specifically, we aim to (I) describe key constituents of engineering students' approaches to a WSP, (II) evaluate these approaches in relation to the normative context of education for sustainable development (ESD), and (III) identify relevant aspects of learning related to WSPs. Aim I is addressed through a phenomenographic study, while aims II and III are addressed by relating the results to research literature about human problem solving, sustainable development, and ESD. We describe four qualitatively different ways of approaching a specific WSP, as the outcome of the phenomenographic study: A. Simplify and avoid, B. Divide and control, C. Isolate and succumb, and D. Integrate and balance. We identify approach D as the most appropriate approach in the context of ESD, while A and C are not. On this basis, we identify three learning objectives related to students' abilities to address WSPs: learn to use a fully integrative approach, distinguish WSPs from tame and well-structured problems, and understand and consider the normative context of SD. Finally, we provide recommendations for how these learning objectives can be used to guide the design of science and engineering educational activities.

  6. ACTIVE VIBRATION CONTROL OF FINITE L-SHAPED BEAM WITH TRAVELLING WAVE APPROACH

    Institute of Scientific and Technical Information of China (English)

    Chunchuan Liu; Fengming Li; Wenhu Huang

    2010-01-01

    In this paper,the disturbance propagation and active vibration control of a finite L-shaped beam are studied.The dynamic response of the structure is obtained by the travelling wave approach.The active vibration suppression of the finite L-shaped beam is performed based on the structural vibration power flow.In the numerical calculation,the influences of the near field effect of the error sensor and the small error of the control forces on the control results are all considered.The simulation results indicate that the structural vibration response in the medium and high frequency regions can be effectively computed by the travelling wave method.The effect of the active control by controlling the power flow is much better than that by controlling the acceleration in some cases.And the control results by the power flow method are slightly affected by the locations of the error sensor and the small error of the control forces.

  7. Well Control Optimization using Derivative-Free Algorithms and a Multiscale Approach

    CERN Document Server

    Wang, Xiang; Feng, Qihong

    2015-01-01

    In this paper, we use numerical optimization algorithms and a multiscale approach in order to find an optimal well management strategy over the life of the reservoir. The large number of well rates for each control step make the optimization problem more difficult and at a high risk of achieving a suboptimal solution. Moreover, the optimal number of adjustments is not known a priori. Adjusting well controls too frequently will increase unnecessary well management and operation cost, and an excessively low number of control adjustments may not be enough to obtain a good yield. We investigate three derivative-free optimization algorithms, chosen for their robust and parallel nature, to determine optimal well control strategies. The algorithms chosen include generalized pattern search (GPS), particle swarm optimization (PSO) and covariance matrix adaptation evolution strategy (CMA-ES). These three algorithms encompass the breadth of available black-box optimization strategies: deterministic local search, stochas...

  8. Control of plasma profile in microwave discharges via inverse-problem approach

    Directory of Open Access Journals (Sweden)

    Yasuyoshi Yasaka

    2013-12-01

    Full Text Available In the manufacturing process of semiconductors, plasma processing is an essential technology, and the plasma used in the process is required to be of high density, low temperature, large diameter, and high uniformity. This research focuses on the microwave-excited plasma that meets these needs, and the research target is a spatial profile control. Two novel techniques are introduced to control the uniformity; one is a segmented slot antenna that can change radial distribution of the radiated field during operation, and the other is a hyper simulator that can predict microwave power distribution necessary for a desired radial density profile. The control system including these techniques provides a method of controlling radial profiles of the microwave plasma via inverse-problem approach, and is investigated numerically and experimentally.

  9. Robust Stability of Fractional Order Time-Delay Control Systems: A Graphical Approach

    Directory of Open Access Journals (Sweden)

    Radek Matušů

    2015-01-01

    Full Text Available The paper deals with a graphical approach to investigation of robust stability for a feedback control loop with an uncertain fractional order time-delay plant and integer order or fractional order controller. Robust stability analysis is based on plotting the value sets for a suitable range of frequencies and subsequent verification of the zero exclusion condition fulfillment. The computational examples present the typical shapes of the value sets of a family of closed-loop characteristic quasipolynomials for a fractional order plant with uncertain gain, time constant, or time-delay term, respectively, and also for combined cases. Moreover, the practically oriented example focused on robust stability analysis of main irrigation canal pool controlled by either classical integer order PID or fractional order PI controller is included as well.

  10. A Novel Approach in Designing PID Controller for Semi-active Quarter Car Model

    Directory of Open Access Journals (Sweden)

    Mehta Vedant

    2016-01-01

    Full Text Available This paper implements Teaching-Learning based optimization (TLBO to obtain optimized value of spring stiffness for better ride comfort. Further, this optimized value is then used in a semi-active quarter car setup to remove any discrepancies due to non-optimized spring. This paper also introduces a novel approach to control the Semi-active suspension parameter (damping coefficient for a better performance. For controlling semi-active parameters, PID controller has been used. PID controller output is fed to the quarter car setup as a damping coefficient. Thus changing the damping coefficient dynamically as the disturbance occurs, and thus improving the ride comfort. The sprung mass acceleration and rattle space of semi-active quarter car has been compared with sprung mass acceleration and rattle space of passive quarter car model to show the difference in results and thereby, results and conclusions are drawn.

  11. Control of noise and structural vibration a MATLAB-based approach

    CERN Document Server

    Mao, Qibo

    2013-01-01

    Control of Noise and Structural Vibration presents a MATLAB®-based approach to solving the problems of undesirable noise generation and transmission by structures and of undesirable vibration within structures in response to environmental or operational forces. The fundamentals of acoustics, vibration and coupling between vibrating structures and the sound fields they generate are introduced including a discussion of the finite element method for vibration analysis. Following this, the treatment of sound and vibration control begins, illustrated by example systems such as beams, plates and double plate structures. Sensor and actuator placement is explained as is the idea of modal sensor–actuators. The design of appropriate feedback systems includes consideration of basic stability criteria and robust active structural acoustic control. Single and multi-mode positive position feedback (PPF) control systems are also described in the context of loudspeaker–duct model with non-collocated loudspeaker–microp...

  12. Multi-criteria decision making approaches for quality control of genome-wide association studies.

    Science.gov (United States)

    Malovini, Alberto; Rognoni, Carla; Puca, Annibale; Bellazzi, Riccardo

    2009-03-01

    Experimental errors in the genotyping phases of a Genome-Wide Association Study (GWAS) can lead to false positive findings and to spurious associations. An appropriate quality control phase could minimize the effects of this kind of errors. Several filtering criteria can be used to perform quality control. Currently, no formal methods have been proposed for taking into account at the same time these criteria and the experimenter's preferences. In this paper we propose two strategies for setting appropriate genotyping rate thresholds for GWAS quality control. These two approaches are based on the Multi-Criteria Decision Making theory. We have applied our method on a real dataset composed by 734 individuals affected by Arterial Hypertension (AH) and 486 nonagenarians without history of AH. The proposed strategies appear to deal with GWAS quality control in a sound way, as they lead to rationalize and make explicit the experimenter's choices thus providing more reproducible results.

  13. A Novel Approach for Automatic Control of Piezoelectric Elements Used for Lorentz Force Detuning Compensation

    CERN Document Server

    Przygoda, K; Napieralski, A; Grecki, M

    2010-01-01

    Abstract: Linear accelerators such as Free Electron Lasers (FELs) use superconducting (SC) resonant cavities to accelerate electron beam to high energies. TESLA type resonators are extremely sensitive to detuning induced by mechanical deformations – Lorentz force detuning (LFD), mainly due to the extremely high quality factor (Q) of the 1.3 GHz resonance mode, in the range of 1e6. The resulting modulation of a resonance frequency of the cavity makes power consumption and stability performances of the Low-Latency Radio Frequency (LLRF) control more critical. In order to minimize the RF control efforts and desired stabilities, the fast piezoelectric actuators with digital control systems are commonly used. The paper presents a novel approach for automatic control of piezoelectric actuators used for compensation of Lorentz force detuning, the practical application and carried out tests in accelerating module ACC6 in Free-Electron Laser in Hamburg (FLASH).

  14. Control of plasma profile in microwave discharges via inverse-problem approach

    Energy Technology Data Exchange (ETDEWEB)

    Yasaka, Yasuyoshi; Tobita, Naoki; Tsuji, Akihiro [Department of Electrical and Electronic Engineering, Kobe University, Kobe 657-8501 (Japan)

    2013-12-15

    In the manufacturing process of semiconductors, plasma processing is an essential technology, and the plasma used in the process is required to be of high density, low temperature, large diameter, and high uniformity. This research focuses on the microwave-excited plasma that meets these needs, and the research target is a spatial profile control. Two novel techniques are introduced to control the uniformity; one is a segmented slot antenna that can change radial distribution of the radiated field during operation, and the other is a hyper simulator that can predict microwave power distribution necessary for a desired radial density profile. The control system including these techniques provides a method of controlling radial profiles of the microwave plasma via inverse-problem approach, and is investigated numerically and experimentally.

  15. A probabilistic approach for predictive congestion control in wireless sensor networks

    Institute of Scientific and Technical Information of China (English)

    R.ANNIE UTHRA; S.V.KASMIR RAJA; A.JEYASEKAR; Anthony J.LATTANZE

    2014-01-01

    Any node in a wireless sensor network is a resource constrained device in terms of memory, bandwidth, and energy, which leads to a large number of packet drops, low throughput, and significant waste of energy due to retransmission. This paper presents a new approach for predicting congestion using a probabilistic method and controlling congestion using new rate control methods. The probabilistic approach used for prediction of the occurrence of congestion in a node is developed using data traffic and buffer occupancy. The rate control method uses a back-off selection scheme and also rate allocation schemes, namely rate regulation (RRG) and split protocol (SP), to improve throughput and reduce packet drop. A back-off interval selection scheme is introduced in combination with rate reduction (RR) and RRG. The back-off interval selection scheme considers channel state and collision-free transmission to prevent congestion. Simulations were conducted and the results were compared with those of de-centralized predictive congestion control (DPCC) and adaptive duty-cycle based congestion control (ADCC). The results showed that the proposed method reduces congestion and improves performance.

  16. Role of right hemifield in visual control of approach to target in zebrafish.

    Science.gov (United States)

    Miklósi, A; Andrew, R J; Gasparini, S

    2001-07-01

    When a zebrafish has to choose between two identical stimuli (e.g. a conditioned stimulus, CS, for food reward), it tends to respond to the one on its right. Errors are more numerous when reinforced for taking the one on the left rather than the one on the right. When trained to a single medial stimulus, and presented in non-reinforced probe trials with a pair of identical stimuli, the one on the right is chosen. Use by zebrafish of right eye (RE), viewing to control a planned motor response, extends from objects that are to be bitten to a choice of one of two routes. When the CS is visible behind a barrier of vertical bars, so that it can be approached around either end, it is the right end that is chosen. Standing motor bias independent of the nature of the task can be excluded. Other vertebrates show RE control of response. Toads are more likely to take food seen with the RE. The domestic chick uses the RE in visual control of approach to an object that has to be manipulated with the bill. RE control of use of the mouth in a fish shows that that this is an earlier condition than lateralised control of bilateral effectors like hands. PMID:11287077

  17. In Silico Magnetic Nanocontainers Navigation in Blood Vessels: A Feedback Control Approach.

    Science.gov (United States)

    Do, Ton Duc; Noh, Yeongil; Kim, Myeong Ok; Yoon, Jungwon

    2016-06-01

    Magnetic nanoparticles (MNPs) are recently used in a drug delivery system to pass the blood brain barrier. However, because the magnetic force acting on particles is proportional to their volumes, as the size of particles is small, the large magnetic field is required to produce enough magnetic force for overcoming the hydrodynamic drag force as well as other forces in blood vessels. Other difficulties for controlling MNPs are the complicated behavior of hydrodynamic drag force and uncertain factors in their dynamics. Therefore, open-loop control methods cannot guarantee guiding every MNP to the correct location. Considering these challenges, this paper introduces a feedback control approach for magnetic nanoparticles (MNPs) in blood vessels. To the best of our knowledge, this is the first time feedback controller that is designed for MNPs without aggregation. Simulation studies in MATLAB and real-time verifications on a physical model in COMSOL-MATLAB interface are performed to prove the feasibility of the proposed approach. It is shown that the proposed control scheme can accurately and effectively navigate the MNP to the correct path with feasible hardware supports. PMID:27427720

  18. In Silico Magnetic Nanocontainers Navigation in Blood Vessels: A Feedback Control Approach.

    Science.gov (United States)

    Do, Ton Duc; Noh, Yeongil; Kim, Myeong Ok; Yoon, Jungwon

    2016-06-01

    Magnetic nanoparticles (MNPs) are recently used in a drug delivery system to pass the blood brain barrier. However, because the magnetic force acting on particles is proportional to their volumes, as the size of particles is small, the large magnetic field is required to produce enough magnetic force for overcoming the hydrodynamic drag force as well as other forces in blood vessels. Other difficulties for controlling MNPs are the complicated behavior of hydrodynamic drag force and uncertain factors in their dynamics. Therefore, open-loop control methods cannot guarantee guiding every MNP to the correct location. Considering these challenges, this paper introduces a feedback control approach for magnetic nanoparticles (MNPs) in blood vessels. To the best of our knowledge, this is the first time feedback controller that is designed for MNPs without aggregation. Simulation studies in MATLAB and real-time verifications on a physical model in COMSOL-MATLAB interface are performed to prove the feasibility of the proposed approach. It is shown that the proposed control scheme can accurately and effectively navigate the MNP to the correct path with feasible hardware supports.

  19. A high energy physics run control system based on an object oriented approach

    International Nuclear Information System (INIS)

    This paper reports describes the Run Control system developed for the Obelix experiment at the Low Energy Antiproton Ring of CERN. The adopted approach is based on a State Manager developed as a part of the MODEL project. The State Manager incorporates a model of the different activities and of the way they must be organized. An object-oriented decomposition of the on-line system is performed. A clean separation of the control. logic and operating tasks is achieved. Remote Procedure Call techniques are employed to cope with the problems of a distributed system architecture

  20. DC Voltage Droop Control Implementation in the AC/DC Power Flow Algorithm: Combinational Approach

    DEFF Research Database (Denmark)

    Akhter, F.; Macpherson, D.E.; Harrison, G.P.;

    2015-01-01

    of operational flexibility, as more than one VSC station controls the DC link voltage of the MTDC system. This model enables the study of the effects of DC droop control on the power flows of the combined AC/DC system for steady state studies after VSC station outages or transient conditions without needing...... to use its complete dynamic model. Further, the proposed approach can be extended to include multiple AC and DC grids for combined AC/DC power flow analysis. The algorithm is implemented by modifying the MATPOWER based MATACDC program and the results shows that the algorithm works efficiently....

  1. Impulse Control Disorders in Parkinson’s Disease:Management, Controversies, and Potential Approaches

    Science.gov (United States)

    Samuel, M; Rodriguez-Oroz, M; Antonini, A; Brotchie, JM; Ray Chaudhuri, K; Brown, RG; Galpern, WR; Nirenberg, MJ; Okun, MS; Lang, AE

    2016-01-01

    Impulse control disorders in Parkinson’s disease are a group of impulsive behaviors most often associated with dopaminergic treatment. Presently, there is a lack of high quality evidence available to guide their management. This manuscript reviews current management strategies, before concentrating on the concept of dopamine agonist withdrawal syndrome and its implications for the management of impulse control disorders. Further, we focus on controversies including the role of more recently available anti-parkinsonian drugs, and potential future approaches involving routes of drug delivery, non-pharmacological treatments (such as cognitive behaviour therapy and deep brain stimulation), and other as yet experimental strategies. PMID:25607799

  2. Series-based approximate approach of optimal tracking control for nonlinear systems with time-delay

    Institute of Scientific and Technical Information of China (English)

    Gongyou Tang; Mingqu Fan

    2008-01-01

    The optimal output tracking control (OTC) problem for nonlinear systems with time-delay is considered.Using a series-based approx-imate approach,the original OTC problem is transformed into iteration solving linear two-point boundary value problems without time-delay.The OTC law obtained consists of analytical linear feedback and feedforward terms and a nonlinear compensation term with an infinite series of the adjoint vectors.By truncating a finite sum of the adjoint vector series,an approximate optimal tracking control law is obtained.A reduced-order reference input observer is constructed to make the feedforward term physically realizable.Simulation exam-pies are used to test the validity of the series-based approximate approach.

  3. Dynamic control approaches of spectrum sensing in multi-band cognitive radio networks

    Institute of Scientific and Technical Information of China (English)

    AN Chun-yan; JI Hong; SI Peng-bo; MAO Xu

    2010-01-01

    In this paper,the dynamic control approaches for spectrum sensing are proposed,based on the theory that prediction is synonymous with data compression in computational learning. Firstly,a spectrum sensing sequence prediction scheme is proposed to reduce the spectrum sensing time and improve the throughput of secondary users. We use Ziv-Lempel data compression algorithm to design the prediction scheme,where spectrum band usage history is utilized. In addition,an iterative algorithm to find out the optimal number of spectrum bands allowed to sense is proposed,with the aim of maximizing the expected net reward of each secondary user in each time slot. Finally,extensive simulation results are shown to demonstrate the effectiveness of the proposed dynamic control approaches of spectrum sensing.

  4. Optimal control theory (OWEM) applied to a helicopter in the hover and approach phase

    Science.gov (United States)

    Born, G. J.; Kai, T.

    1975-01-01

    A major difficulty in the practical application of linear-quadratic regulator theory is how to choose the weighting matrices in quadratic cost functions. The control system design with optimal weighting matrices was applied to a helicopter in the hover and approach phase. The weighting matrices were calculated to extremize the closed loop total system damping subject to constraints on the determinants. The extremization is really a minimization of the effects of disturbances, and interpreted as a compromise between the generalized system accuracy and the generalized system response speed. The trade-off between the accuracy and the response speed is adjusted by a single parameter, the ratio of determinants. By this approach an objective measure can be obtained for the design of a control system. The measure is to be determined by the system requirements.

  5. Low complexity power control approach based on MMSE detection for V-BLAST

    Institute of Scientific and Technical Information of China (English)

    Zhao Kun; Qiu Ling; Zhu Jinkang

    2006-01-01

    A low complexity Per-Antenna Power Control (PAPC) approach based on Minimum Mean Squared Error (MMSE) detection for V-BLAST is proposed in this paper. The PAPC approach is developed for minimizing the Bit Error Rate (BER) averaged over all substreams when the data throughput and the total transmit power keep constant over time. Simulation results show that the Power-controlled V-BLAST (P-BLAST) outperforms the conventional V-BLAST in terms of BER performance with MMSE detector, especially in presence of high spatial correlation between antennas. However, the additional complexity for P-BLAST is not high. When MMSE detector is adopted, the P-BLAST can achieve a comparable BER performance to that of conventional V-BLAST with Maximum Likelihood (ML) detector but with low complexity.

  6. A Novel Approach to Sliding Mode Control of Time-Delay Systems

    Directory of Open Access Journals (Sweden)

    Hongwei Xia

    2013-01-01

    Full Text Available This paper is concerned with the sliding mode control for a class of linear systems with time-varying delays. By utilizing a novel Lyapunov-Krasovskii functional and combining it with the delay fractioning approach as well as the free-weighting matrix technology, a sufficient condition is established such that the resulting sliding mode dynamics is asymptotically stable. Then, a sliding mode controller for reaching motion is synthesized to guarantee that the trajectories of the resulting closed-loop system can be driven onto a prescribed sliding surface and maintained there for all subsequent time. A numerical example is provided to illustrate the effectiveness of the proposed design approach.

  7. A Unified Approach to Energy-Efficient Power Control in Large CDMA Systems

    CERN Document Server

    Meshkati, Farhad; Poor, H Vincent; Schwartz, Stuart C

    2007-01-01

    A unified approach to energy-efficient power control is proposed for code-division multiple access (CDMA) networks. The approach is applicable to a large family of multiuser receivers including the matched filter, the decorrelator, the linear minimum mean-square error (MMSE) receiver, and the (nonlinear) optimal detectors. It exploits the linear relationship that has been shown to exist between the transmit power and the output signal-to-interference-plus-noise ratio (SIR) in the large-system limit. It is shown that, for this family of receivers, when users seek to selfishly maximize their own energy efficiency, the Nash equilibrium is SIR-balanced. In addition, a unified power control (UPC) algorithm for reaching the Nash equilibrium is proposed. The algorithm adjusts the user's transmit powers by iteratively computing the large-system multiuser efficiency, which is independent of instantaneous spreading sequences. The convergence of the algorithm is proved for the matched filter, the decorrelator, and the M...

  8. A controls engineering approach for analyzing airplane input-output characteristics

    Science.gov (United States)

    Arbuckle, P. Douglas

    1991-01-01

    An engineering approach for analyzing airplane control and output characteristics is presented. State-space matrix equations describing the linear perturbation dynamics are transformed from physical coordinates into scaled coordinates. The scaling is accomplished by applying various transformations to the system to employ prior engineering knowledge of the airplane physics. Two different analysis techniques are then explained. Modal analysis techniques calculate the influence of each system input on each fundamental mode of motion and the distribution of each mode among the system outputs. The optimal steady state response technique computes the blending of steady state control inputs that optimize the steady state response of selected system outputs. Analysis of an example airplane model is presented to demonstrate the described engineering approach.

  9. Stabilization of a Wireless Networked Control System with Packet Loss and Time Delay: An ADS Approach

    Directory of Open Access Journals (Sweden)

    Jing Wang

    2012-01-01

    Full Text Available The stabilization problem of a wireless networked control system is considered in this paper. Both time delay and packet loss exist simultaneously in the wireless network. The system is modeled as an asynchronous dynamic system (ADS with unstable subsystems. A sufficient condition for the system to be stable is presented. A numerical example is given to demonstrate the effectiveness of the proposed approach.

  10. State-Feedback H∞ Control for LPV System Using T-S Fuzzy Linearization Approach

    OpenAIRE

    Jizhen Liu; Yang Hu; Zhongwei Lin

    2013-01-01

    This paper discusses the linear parameter varying (LPV) gain scheduling control problem based on the Takagi-Sugeno (T-S) fuzzy linearization approach. Firstly, the affine nonlinear parameter varying (ANPV) description of a class of nonlinear dynamic processes is defined; that is, at any scheduling parameter, the corresponding system is affine nonlinear as usual. For such a class of ANPV systems, a kind of developed T-S fuzzy modeling procedure is proposed to deal with the nonlinearity, ...

  11. A carrot and stick approach to discipline to discipline self-dealing by controlling shareholders

    OpenAIRE

    Gutiérrez, María; Saez, María Isabel

    2010-01-01

    This paper presents an innovative approach to the regulation of self-dealing by controlling shareholders. Our proposal is grounded on the identification -through the lenses of economic analysis- of the shortcomings inherent in the existing legal solutions, ranging from the absolute prohibition of self-dealing, to the prohibition of voting with conflicting interests, or to the imposition of fairness duties to the majority shareholders. We present our proposal for an alternative ...

  12. Robust H∞ Control for Singular Time-Delay Systems via Parameterized Lyapunov Functional Approach

    Directory of Open Access Journals (Sweden)

    Li-li Liu

    2014-01-01

    Full Text Available A new version of delay-dependent bounded real lemma for singular systems with state delay is established by parameterized Lyapunov-Krasovskii functional approach. In order to avoid generating nonconvex problem formulations in control design, a strategy that introduces slack matrices and decouples the system matrices from the Lyapunov-Krasovskii parameter matrices is used. Examples are provided to demonstrate that the results in this paper are less conservative than the existing corresponding ones in the literature.

  13. Animals’ health control efficiency in Northwest Portugal: A two-stage DEA approach.

    OpenAIRE

    Costa, Leonardo; Lansink, Alfons Oude; Silva, Elvira

    2009-01-01

    A two-stage approach is employed to analyze the efficiency of cooperatives responsible for ruminants’ disease control (OPP) at the farm level in Northwest Portugal. In the first stage, Data Envelopment Analysis (DEA) is used to estimate and decompose input-based overall inefficiency for each OPP. The input-based inefficiency measures are generated using the directional input distance function. In the second stage, the inefficiency estimates are regressed on environmental and organizational fa...

  14. REVIEW ON FLOATING DRUG DELIVERY SYSTEMS: AN APPROACH TO ORAL CONTROLLED DRUG DELIVERY VIA GASTRIC RETENTION

    OpenAIRE

    Kadam Shashikant M; Kadam.S.R; Patil.U.S; Ratan G N; Jamkandi.V.G.

    2011-01-01

    Controlled release (CR) dosage forms have been extensively used to improve therapy with many important drugs. Several approaches are currently utilized in prolongation of gastric residence time, including floating drug delivery system, swelling and expanding system, polymeric bioadhesive system, modified shape system, high density system and other delayed gastric emptying devices. However, the development processes are faced with several physiological difficulties such as the inability to res...

  15. Safety concept and operation control approach in the design of small nuclear reactors

    International Nuclear Information System (INIS)

    Operating experience and manifold feasibility studies reveal promising market potential for Small Reactors (SR) in remote areas of Russia. A number of SR designs ranged from few MWth to several dozens MWth are proposed by designers for power or heat production and cogeneration. Some of them are at the detailed design stage and ready for practical implementation. Safety concept and operation control approach of SRs are discussed in the paper using Floating Nuclear Power Plant VOLNOLOM-3 design as a typical example. (author)

  16. AN OVERVIEW ON VARIOUS APPROACHES TO ORAL CONTROLLED DRUG DELIVERY SYSTEM VIA GASTRORETENTIVE DRUG DELIVERY SYSTEM

    OpenAIRE

    Bhalla.Neetika; Deep Arsh; Goswami Manish

    2012-01-01

    In recent years scientific and technological advancements have been made in the research and development of oral drug delivery system. Oral sustained drug delivery system is complicated by limited gastric residence times (GRTs). In order to understand various physiological difficulties to achieve gastric retention, we have summarized important factors controlling gastric retention. To overcome these limitations, various approaches have been proposed to increase gastric residence of drug deli...

  17. A Bayesian hierarchical approach for combining case-control and prospective studies.

    Science.gov (United States)

    Müller, P; Parmigiani, G; Schildkraut, J; Tardella, L

    1999-09-01

    Motivated by the absolute risk predictions required in medical decision making and patient counseling, we propose an approach for the combined analysis of case-control and prospective studies of disease risk factors. The approach is hierarchical to account for parameter heterogeneity among studies and among sampling units of the same study. It is based on modeling the retrospective distribution of the covariates given the disease outcome, a strategy that greatly simplifies both the combination of prospective and retrospective studies and the computation of Bayesian predictions in the hierarchical case-control context. Retrospective modeling differentiates our approach from most current strategies for inference on risk factors, which are based on the assumption of a specific prospective model. To ensure modeling flexibility, we propose using a mixture model for the retrospective distributions of the covariates. This leads to a general nonlinear regression family for the implied prospective likelihood. After introducing and motivating our proposal, we present simple results that highlight its relationship with existing approaches, develop Markov chain Monte Carlo methods for inference and prediction, and present an illustration using ovarian cancer data. PMID:11315018

  18. Robust Impedance Control-based Lyapunov-Hamiltonian Approach for Constrained Robots

    Directory of Open Access Journals (Sweden)

    Haifa Mehdi

    2015-12-01

    Full Text Available A new design of a robust impedance controller for constrained robotic manipulators is presented. The main objective is to stabilize asymptotically, in the task space, the robotic manipulator's end effectors into a desired position, via a desired contact force under model uncertainties and measurement noise. In this work, the proposed approach is enough straightforward for application without force and position control separation. Robust asymptotic stability in the approach is proved using a Hamiltonian-Lyapunov approach. Besides this, a state/parameter observer and an acceleration estimator are proposed to handle the problems of force estimation, disturbance rejection and acceleration measurement. To ensure high performance, a Particle Swarm Optimization (PSO algorithm is used finally as an efficient and fast method for the offline fine-tuning of the controller’s parameters. In designing the PSO method, the Mean of Root Squared Error (MRSE is considered as a cost function in the Cartesian space. Finally, the example of the ABB-IRB 140 industrial robot with 6DOFs is used to validate the performances of the proposed approach.

  19. The Influence of Depression on Cognitive Control: Disambiguating Approach and Avoidance Tendencies.

    Directory of Open Access Journals (Sweden)

    He Huang

    Full Text Available Dysfunctions of approach and avoidance motivation play an important role in depression, which in turn may affect cognitive control, i.e., the ability to regulate thoughts and action to achieve internal goals. We use a novel experimental paradigm, i.e. a computer simulated driving-task, to study the impact of depression on cognitive control by measuring approach and avoidance actions in continuous time. In this task, 39 subjects with minimal to severe depression symptoms were instructed to use a joystick to move a virtual car as quickly as possible to a target point without crossing a stop-sign or crashing into a wall. We recorded their continuous actions on a joystick and found that depression 1 leads to further stopping distance to task target; and 2 increases the magnitude of late deceleration (avoidance but not early acceleration (approach, which was only observed in the stop-sign condition. Taken together, these results are consistent with the hypothesis that depressed individuals have greater avoidance motivation near stopping target, but are minimally affected by approach motivation.

  20. Automated quality control methods for sensor data: a novel observatory approach

    Directory of Open Access Journals (Sweden)

    J. R. Taylor

    2012-12-01

    Full Text Available National and international networks and observatories of terrestrial-based sensors are emerging rapidly. As such, there is demand for a standardized approach to data quality control, as well as interoperability of data among sensor networks. The National Ecological Observatory Network (NEON has begun constructing their first terrestrial observing sites with 60 locations expected to be distributed across the US by 2017. This will result in over 14 000 automated sensors recording more than > 100 Tb of data per year. These data are then used to create other datasets and subsequent "higher-level" data products. In anticipation of this challenge, an overall data quality assurance plan has been developed and the first suite of data quality control measures defined. This data-driven approach focuses on automated methods for defining a suite of plausibility test parameter thresholds. Specifically, these plausibility tests scrutinize data range, persistence, and stochasticity on each measurement type by employing a suite of binary checks. The statistical basis for each of these tests is developed and the methods for calculating test parameter thresholds are explored here. While these tests have been used elsewhere, we apply them in a novel approach by calculating their relevant test parameter thresholds. Finally, implementing automated quality control is demonstrated with preliminary data from a NEON prototype site.

  1. Automated quality control methods for sensor data: a novel observatory approach

    Directory of Open Access Journals (Sweden)

    J. R. Taylor

    2013-07-01

    Full Text Available National and international networks and observatories of terrestrial-based sensors are emerging rapidly. As such, there is demand for a standardized approach to data quality control, as well as interoperability of data among sensor networks. The National Ecological Observatory Network (NEON has begun constructing their first terrestrial observing sites, with 60 locations expected to be distributed across the US by 2017. This will result in over 14 000 automated sensors recording more than > 100 Tb of data per year. These data are then used to create other datasets and subsequent "higher-level" data products. In anticipation of this challenge, an overall data quality assurance plan has been developed and the first suite of data quality control measures defined. This data-driven approach focuses on automated methods for defining a suite of plausibility test parameter thresholds. Specifically, these plausibility tests scrutinize the data range and variance of each measurement type by employing a suite of binary checks. The statistical basis for each of these tests is developed, and the methods for calculating test parameter thresholds are explored here. While these tests have been used elsewhere, we apply them in a novel approach by calculating their relevant test parameter thresholds. Finally, implementing automated quality control is demonstrated with preliminary data from a NEON prototype site.

  2. Complex Event Processing Approach To Automated Monitoring Of Particle Accelerator And Its Control System

    Directory of Open Access Journals (Sweden)

    Karol Grzegorczyk

    2014-01-01

    Full Text Available This article presents the design and implementation of a software component for automated monitoring and diagnostic information analysis of a particle accelerator and its control system. The information that is analyzed can be seen as streams of events. A Complex Event Processing (CEP approach to event processing was selected. The main advantage of this approach is the ability to continuously query data coming from several streams. The presented software component is based on Esper, the most popular open-source implementation of CEP. As a test bed, the control system of the accelerator complex located at CERN, the European Organization for Nuclear Research, was chosen. The complex includes the Large Hadron Collider, the world’s most powerful accelerator. The main contribution to knowledge is by showing that the CEP approach can successfully address many of the challenges associated with automated monitoring of the accelerator and its control system that were previously unsolved. Test results, performance analysis, and a proposal for further works are also presented.

  3. Controlled Positioning of Cells in Biomaterials—Approaches Towards 3D Tissue Printing

    Directory of Open Access Journals (Sweden)

    Sandra Hofmann

    2011-08-01

    Full Text Available Current tissue engineering techniques have various drawbacks: they often incorporate uncontrolled and imprecise scaffold geometries, whereas the current conventional cell seeding techniques result mostly in random cell placement rather than uniform cell distribution. For the successful reconstruction of deficient tissue, new material engineering approaches have to be considered to overcome current limitations. An emerging method to produce complex biological products including cells or extracellular matrices in a controlled manner is a process called bioprinting or biofabrication, which effectively uses principles of rapid prototyping combined with cell-loaded biomaterials, typically hydrogels. 3D tissue printing is an approach to manufacture functional tissue layer-by-layer that could be transplanted in vivo after production. This method is especially advantageous for stem cells since a controlled environment can be created to influence cell growth and differentiation. Using printed tissue for biotechnological and pharmacological needs like in vitro drug-testing may lead to a revolution in the pharmaceutical industry since animal models could be partially replaced by biofabricated tissues mimicking human physiology and pathology. This would not only be a major advancement concerning rising ethical issues but would also have a measureable impact on economical aspects in this industry of today, where animal studies are very labor-intensive and therefore costly. In this review, current controlled material and cell positioning techniques are introduced highlighting approaches towards 3D tissue printing.

  4. Food control and a citizen science approach for improving teaching of Genetics in universities.

    Science.gov (United States)

    Borrell, Y J; Muñoz-Colmenero, A M; Dopico, E; Miralles, L; Garcia-Vazquez, E

    2016-09-10

    A Citizen Science approach was implemented in the laboratory practices of Genetics at the University of Oviedo, related with the engaging topic of Food Control. Real samples of food products consumed by students at home (students as samplers) were employed as teaching material in three different courses of Genetics during the academic year 2014-2015: Experimental Methods in Food Production (MBTA) (Master level), and Applied Molecular Biology (BMA) and Conservation Genetics and Breeding (COMGE) (Bachelor/Degree level). Molecular genetics based on PCR amplification of DNA markers was employed for species identification of 22 seafood products in COMGE and MBTA, and for detection of genetically modified (GM) maize from nine products in BMA. In total six seafood products incorrectly labeled (27%), and two undeclared GM maize (22%) were found. A post-Laboratory survey was applied for assessing the efficacy of the approach for improving motivation in the Laboratory Practices of Genetics. Results confirmed that students that worked on their own samples from local markets were significantly more motivated and better evaluated their Genetic laboratory practices than control students (χ(2)  = 12.11 p = 0.033). Our results suggest that citizen science approaches could not be only useful for improving teaching of Genetics in universities but also to incorporate students and citizens as active agents in food control. © 2016 by The International Union of Biochemistry and Molecular Biology, 44(5):450-462, 2016. PMID:27277420

  5. Food control and a citizen science approach for improving teaching of Genetics in universities.

    Science.gov (United States)

    Borrell, Y J; Muñoz-Colmenero, A M; Dopico, E; Miralles, L; Garcia-Vazquez, E

    2016-09-10

    A Citizen Science approach was implemented in the laboratory practices of Genetics at the University of Oviedo, related with the engaging topic of Food Control. Real samples of food products consumed by students at home (students as samplers) were employed as teaching material in three different courses of Genetics during the academic year 2014-2015: Experimental Methods in Food Production (MBTA) (Master level), and Applied Molecular Biology (BMA) and Conservation Genetics and Breeding (COMGE) (Bachelor/Degree level). Molecular genetics based on PCR amplification of DNA markers was employed for species identification of 22 seafood products in COMGE and MBTA, and for detection of genetically modified (GM) maize from nine products in BMA. In total six seafood products incorrectly labeled (27%), and two undeclared GM maize (22%) were found. A post-Laboratory survey was applied for assessing the efficacy of the approach for improving motivation in the Laboratory Practices of Genetics. Results confirmed that students that worked on their own samples from local markets were significantly more motivated and better evaluated their Genetic laboratory practices than control students (χ(2)  = 12.11 p = 0.033). Our results suggest that citizen science approaches could not be only useful for improving teaching of Genetics in universities but also to incorporate students and citizens as active agents in food control. © 2016 by The International Union of Biochemistry and Molecular Biology, 44(5):450-462, 2016.

  6. Nonlinear approaches in engineering applications applied mechanics, vibration control, and numerical analysis

    CERN Document Server

    Jazar, Reza

    2015-01-01

    This book focuses on the latest applications of nonlinear approaches in different disciplines of engineering. For each selected topic, detailed concept development, derivations, and relevant knowledge are provided for the convenience of the readers. The topics range from dynamic systems and control to optimal approaches in nonlinear dynamics. The volume includes invited chapters from world class experts in the field. The selected topics are of great interest in the fields of engineering and physics and this book is ideal for engineers and researchers working in a broad range of practical topics and approaches. This book also: ·         Explores the most up-to-date applications and underlying principles of nonlinear approaches to problems in engineering and physics, including sections on analytic nonlinearity and practical nonlinearity ·         Enlightens readers to the conceptual significance of nonlinear approaches with examples of applications in scientific and engineering problems from v...

  7. A Non-Intrusive Approach to Enhance Legacy Embedded Control Systems with Cyber Protection Features

    Science.gov (United States)

    Ren, Shangping; Chen, Nianen; Yu, Yue; Poirot, Pierre; Kwiat, Kevin; Tsai, Jeffrey J. P.

    Trust is cast as a continuous re-evaluation: a system’s reliability and security are scrutinized, not just prior to, but during its deployment. This approach to maintaining trust is specifically applied to distributed and embedded control systems. Unlike general purpose systems, distributed and embedded control systems, such as power grid control systems and water treatment systems, etc., generally have a 24x7 availability requirement. Hence, upgrading or adding new cyber protection features into these systems in order to sustain them when faults caused by cyber attacks occur, is often difficult to achieve and inhibits the evolution of these systems into a cyber environment. In this chapter, we present a solution for extending the capabilities of existing systems while simultaneously maintaining the stability of the current systems. An externalized survivability management scheme based on the observe-reason-modify paradigm is applied, which decomposes the cyber attack protection process into three orthogonal subtasks: observation, evaluation and protection. This architecture provides greater flexibility and has a resolvability attribute- it can utilize emerging techniques; yet requires either minimal modifications or even no modifications whatsoever to the controlled infrastructures. The approach itself is general and can be applied to a broad class of observable systems.

  8. An active structural acoustic control approach for the reduction of the structure-borne road noise

    Science.gov (United States)

    Douville, Hugo; Berry, Alain; Masson, Patrice

    2002-11-01

    The reduction of the structure-borne road noise generated inside the cabin of an automobile is investigated using an Active Structural Acoustic Control (ASAC) approach. First, a laboratory test bench consisting of a wheel/suspension/lower suspension A-arm assembly has been developed in order to identify the vibroacoustic transfer paths (up to 250 Hz) for realistic road noise excitation of the wheel. Frequency Response Function (FRF) measurements between the excitation/control actuators and each suspension/chassis linkage are used to characterize the different transfer paths that transmit energy through the chassis of the car. Second, a FE/BE model (Finite/Boundary Elements) was developed to simulate the acoustic field of an automobile cab interior. This model is used to predict the acoustic field inside the cabin as a response to the measured forces applied on the suspension/chassis linkages. Finally, an experimental implementation of ASAC is presented. The control approach relies on the use of inertial actuators to modify the vibration behavior of the suspension and the automotive chassis such that its noise radiation efficiency is decreased. The implemented algorithm consists of a MIMO (Multiple-Input-Multiple-Output) feedforward configuration with a filtered-X LMS algorithm using an advanced reference signal (width FIR filters) using the Simulink/Dspace environment for control prototyping.

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

    Institute of Scientific and Technical Information of China (English)

    冯存芳; 汪映海

    2011-01-01

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

  10. A QoS Control Approach in Differentiated Web Caching Service

    Directory of Open Access Journals (Sweden)

    Ang Gao

    2011-01-01

    Full Text Available As the heterogeneity ofWeb clients increasing, the differentiated service becomes an important issue especially for e-commerce Web site. Web caching as a key accelerator on the Internet plays an important role in alleviating the client-perceived delay. To meet the Service Level Agreement (SLA for clients without excessively over-provisioning resources, this paper proposes and evaluates a novel framework for enforcing Proportional Hit Rate. The framework combines the implement of Isolated Cache Model and the usage of control-theoretical approach for storage control. With system identification, the linear model is identified as well as the controller. At every sampling time, by dynamically reallocating storage spaces for different Web classes, the controller operates to guarantee the relationship of QoS metric among classes constant. The experimental results demonstrate the proposed approach achieves differentiated caching service with the enforcement of Greedy Dual Size Frequency (GDSF, Latest Recently Used (LRU and Latest Frequently Used (LFU cache replacement policies.

  11. An integrodifferential approach to modeling, control, state estimation and optimization for heat transfer systems

    Directory of Open Access Journals (Sweden)

    Rauh Andreas

    2016-03-01

    Full Text Available In this paper, control-oriented modeling approaches are presented for distributed parameter systems. These systems, which are in the focus of this contribution, are assumed to be described by suitable partial differential equations. They arise naturally during the modeling of dynamic heat transfer processes. The presented approaches aim at developing finite-dimensional system descriptions for the design of various open-loop, closed-loop, and optimal control strategies as well as state, disturbance, and parameter estimation techniques. Here, the modeling is based on the method of integrodifferential relations, which can be employed to determine accurate, finite-dimensional sets of state equations by using projection techniques. These lead to a finite element representation of the distributed parameter system. Where applicable, these finite element models are combined with finite volume representations to describe storage variables that are—with good accuracy—homogeneous over sufficiently large space domains. The advantage of this combination is keeping the computational complexity as low as possible. Under these prerequisites, real-time applicable control algorithms are derived and validated via simulation and experiment for a laboratory-scale heat transfer system at the Chair of Mechatronics at the University of Rostock. This benchmark system consists of a metallic rod that is equipped with a finite number of Peltier elements which are used either as distributed control inputs, allowing active cooling and heating, or as spatially distributed disturbance inputs.

  12. ESTABLISHMENT OF SATELLITE FORMATION WITH INITIAL UNCERTAINTY BY CONTROL LYAPUNOV FUNCTION APPROACH

    Directory of Open Access Journals (Sweden)

    M. Navabi

    2012-03-01

    Full Text Available In recent years, dynamics and control of satellite formation flying have been active areas of research. From the mission planning perspective, three main areas namely formation establishment, maintenance and reconfiguration have been discussed. In this paper, a study of formation establishment under initial uncertainty is presented. In this regard, dynamics of low Earth orbit satellite formation is discussed. Control Lyapunov function approach is adopted to bring a deputy satellite, with perturbed initial conditions into formation with a chief satellite. In order to take account of the initial orbit insertion error, uncertainty in initial conditions of the deputy satellite is considered. For a case study, a relatively small formation is adopted, with air-launched Pegasus as the launch vehicle. For several initial conditions, control function and required time to achieve a given mission accuracy are determined, and results are provided as illustration.

  13. A Roll Controlling Approach for a Simple Dual-Actuated Flapping Aerial Vehicle Model

    Directory of Open Access Journals (Sweden)

    Labib Omar El-Farouk E.

    2016-01-01

    Full Text Available Aerial vehicles have been investigated recently in different contexts, due to their high potential of utilization in multiple application areas. Different mechanisms can be used for aerial vehicles actuation, such as the rotating multi-blade systems (Multi-Copters and more recently flapping wings. Flapping wing robots have attracted much attention from researchers in recent years. In this study, a simple dual-actuated flapping mechanism is proposed for actuating a flapping wing robot. The mechanism is designed, simulated and validated in both simulation and experiments. A roll controlling approach is proposed to control the roll angle of the robot via controlling the speeds of both motors actuating each of the wings. The results achieved are validated experimentally, and are promising opening the door for further investigation using our proposed system

  14. An LMI approach to robust H-infinity control for uncertain singular time-delay systems

    Institute of Scientific and Technical Information of China (English)

    Xiaofu JI; Hongye SU; Jian CHU

    2006-01-01

    The problem of robust H-infinity control for a class of uncertain singular time-delay systems is studied in this paper. A new approach is proposed to describe the relationship between slow and fast subsystems of singular time-delay systems, based on which, a sufficient condition is presented for a singular time-delay system to be regular, impulse free and stable with an H-infinity performance. The robust H-infinity control problem is solved and an explicit expression of the desired state-feedback control law is also given. The obtained results are formulated in terms of strict linear matrix inequalities (LMIs) involving no decomposition of system matrices. A numerical example is given to show the effectiveness of the proposed method,

  15. A fuzzy reinforcement learning approach to power control in wireless transmitters.

    Science.gov (United States)

    Vengerov, David; Bambos, Nicholas; Berenji, Hamid R

    2005-08-01

    We address the issue of power-controlled shared channel access in wireless networks supporting packetized data traffic. We formulate this problem using the dynamic programming framework and present a new distributed fuzzy reinforcement learning algorithm (ACFRL-2) capable of adequately solving a class of problems to which the power control problem belongs. Our experimental results show that the algorithm converges almost deterministically to a neighborhood of optimal parameter values, as opposed to a very noisy stochastic convergence of earlier algorithms. The main tradeoff facing a transmitter is to balance its current power level with future backlog in the presence of stochastically changing interference. Simulation experiments demonstrate that the ACFRL-2 algorithm achieves significant performance gains over the standard power control approach used in CDMA2000. Such a large improvement is explained by the fact that ACFRL-2 allows transmitters to learn implicit coordination policies, which back off under stressful channel conditions as opposed to engaging in escalating "power wars." PMID:16128459

  16. Control of molecular rotor rotational frequencies in porous coordination polymers using a solid-solution approach.

    Science.gov (United States)

    Inukai, Munehiro; Fukushima, Tomohiro; Hijikata, Yuh; Ogiwara, Naoki; Horike, Satoshi; Kitagawa, Susumu

    2015-09-30

    Rational design to control the dynamics of molecular rotors in crystalline solids is of interest because it offers advanced materials with precisely tuned functionality. Herein, we describe the control of the rotational frequency of rotors in flexible porous coordination polymers (PCPs) using a solid-solution approach. Solid-solutions of the flexible PCPs [{Zn(5-nitroisophthalate)x(5-methoxyisophthalate)1-x(deuterated 4,4'-bipyridyl)}(DMF·MeOH)]n allow continuous modulation of cell volume by changing the solid-solution ratio x. Variation of the isostructures provides continuous changes in the local environment around the molecular rotors (pyridyl rings of the 4,4'-bipyridyl group), leading to the control of the rotational frequency without the need to vary the temperature. PMID:26368067

  17. Linear matrix inequality approach for synchronization control of fuzzy cellular neural networks with mixed time delays

    Institute of Scientific and Technical Information of China (English)

    P. Balasubramaniam; M. Kalpana; R. Rakkiyappan

    2012-01-01

    Fuzzy cellular neural networks (FCNNs) are special kinds of cellular neural networks (CNNs).Each cell in an FCNN contains fuzzy operating abilities.The entire network is governed by cellular computing laws.The design of FCNNs is based on fuzzy local rules.In this paper,a linear matrix inequality (LMI) approach for synchronization control of FCNNs with mixed delays is investigated.Mixed delays include discrete time-varying delays and unbounded distributed delays.A dynamic control scheme is proposed to achieve the synchronization between a drive network and a response network.By constructing the Lyapunov-Krasovskii functional which contains a triple-integral term and the free-weighting matrices method an improved delay-dependent stability criterion is derived in terms of LMIs.The controller can be easily obtained by solving the derived LMIs.A numerical example and its simulations are presented to illustrate the effectiveness of the proposed method.

  18. Variable speed wind turbine control by discrete-time sliding mode approach.

    Science.gov (United States)

    Torchani, Borhen; Sellami, Anis; Garcia, Germain

    2016-05-01

    The aim of this paper is to propose a new design variable speed wind turbine control by discrete-time sliding mode approach. This methodology is designed for linear saturated system. The saturation constraint is reported on inputs vector. To this end, the back stepping design procedure is followed to construct a suitable sliding manifold that guarantees the attainment of a stabilization control objective. It is well known that the mechanisms are investigated in term of the most proposed assumptions to deal with the damping, shaft stiffness and inertia effect of the gear. The objectives are to synthesize robust controllers that maximize the energy extracted from wind, while reducing mechanical loads and rotor speed tracking combined with an electromagnetic torque. Simulation results of the proposed scheme are presented.

  19. Variable speed wind turbine control by discrete-time sliding mode approach.

    Science.gov (United States)

    Torchani, Borhen; Sellami, Anis; Garcia, Germain

    2016-05-01

    The aim of this paper is to propose a new design variable speed wind turbine control by discrete-time sliding mode approach. This methodology is designed for linear saturated system. The saturation constraint is reported on inputs vector. To this end, the back stepping design procedure is followed to construct a suitable sliding manifold that guarantees the attainment of a stabilization control objective. It is well known that the mechanisms are investigated in term of the most proposed assumptions to deal with the damping, shaft stiffness and inertia effect of the gear. The objectives are to synthesize robust controllers that maximize the energy extracted from wind, while reducing mechanical loads and rotor speed tracking combined with an electromagnetic torque. Simulation results of the proposed scheme are presented. PMID:26804750

  20. Different approaches to modelling the cost-effectiveness of schistosomiasis control

    Directory of Open Access Journals (Sweden)

    Guyatt Helen

    1998-01-01

    Full Text Available This paper reviews three different approaches to modelling the cost-effectiveness of schistosomiasis control. Although these approaches vary in their assessment of costs, the major focus of the paper is on the evaluation of effectiveness. The first model presented is a static economic model which assesses effectiveness in terms of the proportion of cases cured. This model is important in highlighting that the optimal choice of chemotherapy regime depends critically on the level of budget constraint, the unit costs of screening and treatment, the rates of compliance with screening and chemotherapy and the prevalence of infection. The limitations of this approach is that it models the cost-effectiveness of only one cycle of treatment, and effectiveness reflects only the immediate impact of treatment. The second model presented is a prevalence-based dynamic model which links prevalence rates from one year to the next, and assesses effectiveness as the proportion of cases prevented. This model was important as it introduced the concept of measuring the long-term impact of control by using a transmission model which can assess reduction in infection through time, but is limited to assessing the impact only on the prevalence of infection. The third approach presented is a theoretical framework which describes the dynamic relationships between infection and morbidity, and which assesses effectiveness in terms of case-years prevented of infection and morbidity. The use of this model in assessing the cost-effectiveness of age-targeted treatment in controlling Schistosoma mansoni is explored in detail, with respect to varying frequencies of treatment and the interaction between drug price and drug efficacy.

  1. A State-Space Modeling Approach for Active Structural Acoustic Control

    Directory of Open Access Journals (Sweden)

    Leopoldo P.R. de Oliveira

    2009-01-01

    Full Text Available The demands for improvement in sound quality and reduction of noise generated by vehicles are constantly increasing, as well as the penalties for space and weight of the control solutions. A promising approach to cope with this challenge is the use of active structural-acoustic control. Usually, the low frequency noise is transmitted into the vehicle's cabin through structural paths, which raises the necessity of dealing with vibro-acoustic models. This kind of models should allow the inclusion of sensors and actuators models, if accurate performance indexes are to be accessed. The challenge thus resides in deriving reasonable sized models that integrate structural, acoustic, electrical components and the controller algorithm. The advantages of adequate active control simulation strategies relies on the cost and time reduction in the development phase. Therefore, the aim of this paper is to present a methodology for simulating vibro-acoustic systems including this coupled model in a closed loop control simulation framework that also takes into account the interaction between the system and the control sensors/actuators. It is shown that neglecting the sensor/actuator dynamics can lead to inaccurate performance predictions.

  2. Controller Design for Electric Power Steering System Using T-S Fuzzy Model Approach

    Institute of Scientific and Technical Information of China (English)

    Xin Li; Xue-Ping Zhao; Jie Chen

    2009-01-01

    Pressure ripples in electric power steering (EPS) systems can be caused by the phase lag between the driver's steering torque and steer angle, the nonlinear frictions, and the disturbances from road and sensor noise especially during high-frequency maneuvers. This paper investigates the use of the robust fuzzy control method for actively reducing pressure ripples for EPS systems. Remarkable progress on steering maneuverability is achieved. The EPS dynamics is described with an eight-order nonlinear state-space model and approximated by a Takagi-Sugeno (T-S) fuzzy model with time-varying delays and external disturbances. A stabilization approach is then presented for nonlinear time-delay systems through fuzzy state feedback controller in parallel distributed compensation (PDC) structure. The closed-loop stability conditions of EPS system with the fuzzy controller are parameterized in terms of the linear matrix inequality (LMI) problem. Simulations and experiments using the proposed robust fuzzy controller and traditional PID controller have been carried out for EPS systems. Both the simulation and experiment results show that the proposed fuzzy controller can reduce the torque ripples and allow us to have a good steering feeling and stable driving.

  3. Regulatory and safety evaluation approach of digital instrumentation and control systems

    International Nuclear Information System (INIS)

    The instrumentation and control system of nuclear power plant has been a drastic change by introducing software-oriented digital system, digital data communication and man-machine interface technology. In response to this change, regulatory methodologies and approaches need to be changed. It is also expected that the regulatory methodology and approach which are not completely justified in the States as well as developed countries will be significantly changed in the future and regulatory requirements and standards will be also modified and supplemented continuously. In this context, the focused issues such as the methodologies of software verification/validation, the analysis of defense-in-depth and diversity, electromagnetic interference, the performance of real time, and the independence of data communication should be studied and resolved consistently. This paper presents regulatory issues and approaches of the digitalized instrumentation and control system which can be applied in the Korea Next Generation Reactor (KNGR), operating nuclear power plant (NPP) for upgrading or a new NPP

  4. The economic benefits of fertility control: a critical analysis of the investment approach.

    Science.gov (United States)

    Badari, V S

    1977-01-01

    Developing countries are experiencing rapid population growth, which hinders development of economic planning. There are 2 ways to determine the gain to the economy resulting from preventing a birth: a macro-economic growth approach, which establishes a comparison of the income per capita of a country with and without fertility control, and the investment approach which weighs the advantages and disadvantages of additional births in terms of the anticipated future production and consumption of these births, compared with the gain of preventing them. If decrease of population growth helps development planning, it makes sense to establish incentive payments for preventing a birth. Arguments against the investment approach are: the amount spent for bonuses could be higher than the amount saved; it could be used for new investment. In the discounting procedure, consumption has been exagerated while reducing the value of production. Leibenstein's contention is that family programs are followed more by middle class families, whose children won't become marginal workers. These critics have been refuted. Enke, main contributor to this approach, states that the incentive payment should not exceede the value of preventing a birth. Also, to avoid the cost of resources the bonus could be given in services and productive goods. The discounting procedure has been considered valid in those cases in which present consumption is more relevant than future consumption and investible funds, in which case discounting is unavoidable. On the other hand, if incentives are offered, more participation of the poorer classes can be expected. Based on the investment approach, some economists, like Enke and Badari, analized the worth of an averted birth in India and agreed that the gains were substantial. This indicated that the investment approach is a useful guide for developing countries. PMID:12261074

  5. Systems Approach for Designing Cordierite Ceramic Converters for Automotive Emissions Control

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The successful application of porous cordierite ceramic monolithic converters for automotive emissions control over the past 24 years in North America has been attributed to systems approach for optimizing the total converter package from reliability point of view. The systems approach examines the interaction between various components of monolithic converter package, namely the cordierite substrate, the alumina washcoat, the braided wire-rope end seals, the intumescent ceramic mat or steel wiremesh, and the stainless steel can, from long-term durability point of view. Such an approach has also proven successful in the Japanese, European, Korean and South American automotive industries. The key objectives of this paper are: i) to describe Corning′s methodology for assessing the impact of alumina washcoat on mechanical and thermal integrities of cordierite converter; ii) to examine the impact of mount density of ceramic mat or steel wiremesh on containment of cordierite converter against engine vibrations, gas pulsations and thermal gradients, and; iii) to analyze the impact of can design on strength and thermal shock resistance of cordierite converter. The above objectives will be illustrated by several examples of successful converter design for automobiles. This paper also addresses the Chinese automotive converter requirements and how they might be met via systems approach.

  6. Tobacco control approaches and inequity--how far have we come and where are we going?

    Science.gov (United States)

    Purcell, Kate R; O'Rourke, Kerryn; Rivis, Maya

    2015-09-01

    Despite Australia's success in reducing smoking rates, substantial inequities persist--with high smoking prevalence among disadvantaged groups. This article uses Fair Foundations: The VicHealth framework for health equity to identify promising strategies for promoting equity within tobacco control policies and programmes. A rapid review of the Australian and international literature was conducted in March 2014 using Pubmed, ISI web of Science and Scopus, Cochrane library and Google Scholar. A search of the grey literature was conducted to identify promising policy interventions. Population health surveys suggest that tobacco-related inequities in Victoria are beginning to decline. Data from the Victorian Smoking Survey shows that the inequity gap is narrowing, and in recent years, the prevalence of regular smoking declined fastest among disadvantaged smokers. Future approaches to accelerate reductions in tobacco-related inequities include: (i) continue proven population-based tobacco control policies--especially increasing the price of tobacco (while remaining cognisant of the increased economic burden for those smokers who do not quit), and continuing mass media campaigns; (ii) strengthening social policies to promote equity in early child development; educational experiences; quality of local environments; employment and working conditions; (iii) identifying and investing in targeted approaches to influence social norms and more effectively identify and support disadvantaged smokers to quit; (iv) within tobacco control programmes, give greatest priority to interventions focused on adult smokers (including pregnant women and their partners). PMID:26420813

  7. A new intelligent approach for air traffic control using gravitational search algorithm

    Indian Academy of Sciences (India)

    Kazem Dastgerdi; Nasser Mehrshad; Mohsen Farshad

    2016-02-01

    Aircraft landing planning (ALP) is one of the most important challenging problems in the domain of air traffic control (ATC). Solving this NP-hard problem is a valuable aid in organizing air traffic in terminal control area (TCA), which itself leads to a decrease in aircraft fuel consumption, costs of airlines, and workload undertaken by air traffic controllers. In the present paper, the ALP problem is dealt with by applying effective rich knowledge to the optimization process (to remove obvious non-optimal solutions), and the first use of Gravitational Search Algorithm (GSA) in resolving such a case. In this regard, while the specific regulations for safe separation have been observed, the optimal landing time, the optimal runway, and the order of consecutive landings have been determined so that the main goal (minimizing total flight delays) would be best met. Results of simulations show that this approach, compared to previous ones, which are based on Genetic and Bionomic algorithms, GLS, and Scatter search method, considerably decreases total flight delays. Attaining zero in the total flight delays in three scenarios with real data shows that the suggested intelligent approach is more decisive than others in finding an optimal solution.

  8. Maximum performance synergy: A new approach to recording studio control room design

    Science.gov (United States)

    Szymanski, Jeff D.

    2003-10-01

    Popular recording studio control room designs include LEDE(tm), RFZ(tm), and nonenvironment rooms. The common goal of all of these is to create an accurate acoustical environment that does not distort or otherwise color audio reproduction. Also common to these designs is the frequent need to have multiple ancillary recording rooms, often adjacent to the main control room, where group members perform. This approach, where group members are physically separated from one another, can lead to lack of ensemble in the finished recordings. New twists on old acoustical treatment techniques have been implemented at a studio in Nashville, Tennessee, which minimize the need for multiple ancillary recording rooms, thus creating an environment where talent, producer and recording professionals can all occupy the same space for maximum performance synergy. Semi-separated performance areas are designed around a central, critical listening area. The techniques and equipment required to achieve this separation are reviewed, as are advantages and disadvantages to this new control room design approach.

  9. Path Planning of Mobile Elastic Robotic Arms by Indirect Approach of Optimal Control

    Directory of Open Access Journals (Sweden)

    Moharam Habibnejad Korayem

    2011-03-01

    Full Text Available Finding optimal trajectory is critical in several applications of robot manipulators. This paper is applied the open-loop optimal control approach for generating the optimal trajectory of the flexible mobile manipulators in point-to-point motion. This method is based on the Pontryagin-s minimum principle that by providing a two-point boundary value problem is solved the problem. This problem is known to be complex in particular when combined motion of the base and manipulator, non-holonomic constraint of the base and highly non-linear and complicated dynamic equations as a result of flexible nature of links are taken into account. The study emphasizes on modeling of the complete optimal control problem by remaining all nonlinear state and costate variables as well as control constraints. In this method, designer can compromise between different objectives by considering the proper penalty matrices and it yields to choose the proper trajectory among the various paths. The effectiveness and capability of the proposed approach are demonstrated through simulation studies. Finally, to verify the proposed method, the simulation results obtained from the model are compared with the results of those available in the literature.

  10. Optimal congestion control algorithm for ad hoc networks: Penalty function-based approach

    Institute of Scientific and Technical Information of China (English)

    XU Wet-qiang; WU Tie-jun

    2006-01-01

    In this paper, based on the inherent characteristic of the contention relation between flows in ad hoc networks, we introduce the notion of the link's interference set, extend the utility maximization problem representing congestion control in wireline networks to ad hoc networks, apply the penalty function approach and the subgradient method to solve this problem, and propose the congestion control algorithm Penalty function-based Optical Congestion Control (POCC) which is implemented in NS2 simulator. Specifically, each link transmits periodically the information on its congestion state to its interference set; the session at each source adjusts the transmission rate based on the optimal tradeoffbetween the utility value and the congestion level which the interference set of the links that this session goes though suffers from. MATLAB-based simulation results showed that POCC can approach the globally optimal solution. The NS2-based simulation results showed that POCC outperforms default TCP and ATCP to achieve efficient and fair resource allocation in ad hoc networks.

  11. Mite Pests in Plant Crops – Current Issues, Inovative Approaches and Possibilities for Controlling Them (2

    Directory of Open Access Journals (Sweden)

    Radmila Petanović

    2010-01-01

    Full Text Available Part one discusses some principal mite pests in agroecosystems and urban horticulturein European countries, Serbia and its neighbouring countries focusing primarily on issueswith regard to plant production, novel methods and approaches in applied acaralogy. Parttwo displays some major properties of acaricides inhibiting respiration, growth and developmentand other synthetic substances with acaricide action on the market in the last decadeof the 20th century and the first decade of the 21st century. Also some products of naturalorigin (azadirachtin, oils, micoacaricides are said to be gaining in importance. Issues withregard to the fact that mites can readily develop resistance to acardicides are discussed anda survey on the results of biochemical, physiological and genetical causes of resistance areanalyzed. Some basic principles of biological control of phytophagous mites and modernadvances and approaches are discussed as well as current knowledge on host plant resistanceto mites. Eventually, the possibility of using a combination of selective acaricides andbiological control agents is discussed but also the inclusion of other modes of control (agriculturalpractices and physical measures expected to contribute to an integrated managementof pest populations.

  12. Effects of higher order control systems on aircraft approach and landing longitudinal handling qualities

    Science.gov (United States)

    Pasha, M. A.; Dazzo, J. J.; Silverthorn, J. T.

    1982-01-01

    An investigation of approach and landing longitudinal flying qualities, based on data generated using a variable stability NT-33 aircraft combined with significant control system dynamics is described. An optimum pilot lead time for pitch tracking, flight path angle tracking, and combined pitch and flight path angle tracking tasks is determined from a closed loop simulation using integral squared error (ISE) as a performance measure. Pilot gain and lead time were varied in the closed loop simulation of the pilot and aircraft to obtain the best performance for different control system configurations. The results lead to the selection of an optimum lead time using ISE as a performance criterion. Using this value of optimum lead time, a correlation is then found between pilot rating and performance with changes in the control system and in the aircraft dynamics. It is also shown that pilot rating is closely related to pilot workload which, in turn, is related to the amount of lead which the pilot must generate to obtain satisfactory response. The results also indicate that the pilot may use pitch angle tracking for the approach task and then add flight path angle tracking for the flare and touchdown.

  13. Mentoring SFRM: A New Approach to International Space Station Flight Controller Training

    Science.gov (United States)

    Huning, Therese; Barshi, Immanuel; Schmidt, Lacey

    2008-01-01

    The Mission Operations Directorate (MOD) of the Johnson Space Center is responsible for providing continuous operations support for the International Space Station (ISS). Operations support requires flight controllers who are skilled in team performance as well as the technical operations of the ISS. Space Flight Resource Management (SFRM), a NASA adapted variant of Crew Resource Management (CRM), is the competency model used in the MOD. ISS flight controller certification has evolved to include a balanced focus on development of SFRM and technical expertise. The latest challenge the MOD faces is how to certify an ISS flight controller (operator) to a basic level of effectiveness in 1 year. SFRM training uses a two-pronged approach to expediting operator certification: 1) imbed SFRM skills training into all operator technical training and 2) use senior flight controllers as mentors. This paper focuses on how the MOD uses senior flight controllers as mentors to train SFRM skills. Methods: A mentor works with an operator throughout the training flow. Inserted into the training flow are guided-discussion sessions and on-the-job observation opportunities focusing on specific SFRM skills, including: situational leadership, conflict management, stress management, cross-cultural awareness, self care and team care while on-console, communication, workload management, and situation awareness. The mentor and operator discuss the science and art behind the skills, cultural effects on skills applications, recognition of good and bad skills applications, recognition of how skills application changes subtly in different situations, and individual goals and techniques for improving skills. Discussion: This mentoring program provides an additional means of transferring SFRM knowledge compared to traditional CRM training programs. Our future endeavors in training SFRM skills (as well as other organization s) may benefit from adding team performance skills mentoring. This paper

  14. Control of codling moth (Cydia pomonella) using the area-wide approach in Chile

    International Nuclear Information System (INIS)

    Full text: Management of codling moth (CM) is being conducted in southern Chile using an area-wide approach and integrating different tools such us Geographic Information System (GIS), classical biological control, inundative biological control and mating disruption. The total area covers 6,000 ha, and extends from the foothills of the Andes mountains and is bordered in the south and north by rivers. Vegetation cover is predominantly pastures, pine forests and berries, including six commercial apple orchards. Codling moth control in the commercial orchards is based on chemical insecticides, mating disruption or organic practices. Many alternative hosts for CM grow in this area, mainly as ornamentals, in abandoned orchards and in gardens for self-consumption. The most important species are noncommercial apple, pear, quince, walnut and apricot. Satellite images were obtained and every alternate host tree was georeferenced and drawn on these images. Pheromone traps are being used to identify main migrant sources and to quantify migration from sources to commercial orchards. Classical biological control includes importation and release of an egg/larval parasitoid (Ascogaster quadridentata) from USA to Chile. CM is reared on artificial diet and eggs are used to increase the A. quadridentata colony and allow field releases in the 2004-2005 growing season, especially in isolated and abandoned trees. Related to inundative biological control, several strains of entomopathogenic organisms have been collected and evaluated against CM, including the fungus (Beauveria bassiana) and nematodes. In addition, a Chilean species of trichogrammatid wasps, Trichogramma nerudai and Trichogramma caccociae, have been used under an inundative approach, especially in abandoned orchards. The Chilean species T. nerudai has shown similar or better preference and laboratory performance than introduced species such as T. bactrae, T. caccociae, T. dendrolimi and T. platneri. (author)

  15. A Sum-of-Squares approach to feedback control of laminar wake flows

    CERN Document Server

    Lasagna, Davide; Tutty, Owen R; Chernyshenko, Sergei

    2016-01-01

    A novel nonlinear feedback control design methodology for incompressible fluid flows aiming at the optimisation of long-time averages of flow quantities is presented. It applies to reduced-order finite-dimensional models of fluid flows, expressed as a set of first-order nonlinear ordinary differential equations with the right-hand side being a polynomial function in the state variables and in the controls. The key idea, first discussed in Chernyshenko et al. 2014, Philos. T. Roy. Soc. 372(2020), is that the difficulties of treating and optimising long-time averages of a cost are relaxed by using the upper/lower bounds of such averages as the objective function. In this setting, control design reduces to finding a feedback controller that optimises the bound, subject to a polynomial inequality constraint involving the cost function, the nonlinear system, the controller itself and a tunable polynomial function. A numerically tractable approach to the solution of such optimisation problems, based on Sum-of-Squar...

  16. A boundary element approach to optimization of active noise control sources on three-dimensional structures

    Science.gov (United States)

    Cunefare, K. A.; Koopmann, G. H.

    1991-01-01

    This paper presents the theoretical development of an approach to active noise control (ANC) applicable to three-dimensional radiators. The active noise control technique, termed ANC Optimization Analysis, is based on minimizing the total radiated power by adding secondary acoustic sources on the primary noise source. ANC Optimization Analysis determines the optimum magnitude and phase at which to drive the secondary control sources in order to achieve the best possible reduction in the total radiated power from the noise source/control source combination. For example, ANC Optimization Analysis predicts a 20 dB reduction in the total power radiated from a sphere of radius at a dimensionless wavenumber ka of 0.125, for a single control source representing 2.5 percent of the total area of the sphere. ANC Optimization Analysis is based on a boundary element formulation of the Helmholtz Integral Equation, and thus, the optimization analysis applies to a single frequency, while multiple frequencies can be treated through repeated analyses.

  17. Hybrid Vibration Control under Broadband Excitation and Variable Temperature Using Viscoelastic Neutralizer and Adaptive Feedforward Approach

    Directory of Open Access Journals (Sweden)

    João C. O. Marra

    2016-01-01

    Full Text Available Vibratory phenomena have always surrounded human life. The need for more knowledge and domain of such phenomena increases more and more, especially in the modern society where the human-machine integration becomes closer day after day. In that context, this work deals with the development and practical implementation of a hybrid (passive-active/adaptive vibration control system over a metallic beam excited by a broadband signal and under variable temperature, between 5 and 35°C. Since temperature variations affect directly and considerably the performance of the passive control system, composed of a viscoelastic dynamic vibration neutralizer (also called a viscoelastic dynamic vibration absorber, the associative strategy of using an active-adaptive vibration control system (based on a feedforward approach with the use of the FXLMS algorithm working together with the passive one has shown to be a good option to compensate the neutralizer loss of performance and generally maintain the extended overall level of vibration control. As an additional gain, the association of both vibration control systems (passive and active-adaptive has improved the attenuation of vibration levels. Some key steps matured over years of research on this experimental setup are presented in this paper.

  18. An Approach to Enforcing Clark-Wilson Model in Role-based Access Control Model

    Institute of Scientific and Technical Information of China (English)

    LIANGBin; SHIWenchang; SUNYufang; SUNBo

    2004-01-01

    Using one security model to enforce another is a prospective solution to multi-policy support. In this paper, an approach to the enforcing Clark-Wilson data integrity model in the Role-based access control (RBAC) model is proposed. An enforcement construction with great feasibility is presented. In this construction, a direct way to enforce the Clark-Wilson model is provided, the corresponding relations among users, transformation procedures, and constrained data items are strengthened; the concepts of task and subtask are introduced to enhance the support to least-privilege. The proposed approach widens the applicability of RBAC. The theoretical foundation for adopting Clark-Wilson model in a RBAC system with small cost is offered to meet the requirements of multi-policy support and policy flexibility.

  19. A Delay System Approach to Fault Detection Filter of Networked Control Systems

    Institute of Scientific and Technical Information of China (English)

    MA Li-wei; TIAN Zuo-hua; SHI Song-jiao; WENG Zheng-xin

    2009-01-01

    In this paper, the fault detection filter (FDF) design problem for networked control systems (NCSs) with both network-induced delay and data dropout is studied. Based on a new NCSs model proposed recently, an observer-based filter is introduced to be the residual generator and formulated as an H∞-optimization problem for systems with two successive delay components. By applying Lyapunov-Krasovskii approach, a new sufficient condition on stability and H∞ performance is derived for systems with two successive delay components in the state. A solution of the optimization problem is then presented in terms of linear matrix inequality (LMI) formulation, dependently of time delay. In order to detect the fault, the residual evaluation problem is also considered. An illustrative design example is employed to demonstrate the validity of the proposed approach.

  20. Iterative Learning Control Approach for Signaling Split in Urban Traffic Networks with Macroscopic Fundamental Diagrams

    Directory of Open Access Journals (Sweden)

    Fei Yan

    2015-01-01

    Full Text Available Recent analysis of field experiments in cities revealed that a macroscopic fundamental diagram (MFD relating network outflow and network vehicle accumulation exists in the urban traffic networks. It has been further confirmed that an MFD is well defined if the network has regular network topology and homogeneous spatial distribution of vehicle accumulation. However, many real urban networks have different levels of heterogeneity in the spatial distribution of vehicle accumulation. In order to improve the mobility in heterogeneously congested networks, we propose an iterative learning control approach for signaling split, which aims at distributing the accumulation in the networks as homogeneously as possible and ensuring the networks have a larger outflow. The asymptotic convergence of the proposed approach is proved by rigorous analysis and the effectiveness is further demonstrated by extensive simulations.

  1. A One-Health integrated approach to control fascioliasis in the Cajamarca valley of Peru

    Directory of Open Access Journals (Sweden)

    Laura Rinaldi

    2012-09-01

    Full Text Available Fasciola hepatica infection is reported from many Latin American countries, with very high prevalence rates in both humans and livestock in the Andean countries. Due to its environmental characteristics, particularly suitable for liver fluke infection, the Cajamarca valley of Peru has often been chosen as a model to study the epidemiology of liver fluke infection in the Andes. In this paper we describe the profile of a project aimed at a multidisciplinary and integrated approach for the control of fascioliasis in animals and humans in this valley. The One-Health integrated approach applied here is based on accurate and sensitive diagnostics, namely the FLOTAC, and the use of geospatial tools for epidemiological scrutiny.

  2. Acceptability of impregnated school uniforms for dengue control in Thailand: a mixed methods approach

    Directory of Open Access Journals (Sweden)

    Natasha Murray

    2014-09-01

    Full Text Available Background: As current dengue control strategies have been shown to be largely ineffective in reducing dengue in school-aged children, novel approaches towards dengue control need to be studied. Insecticide-impregnated school uniforms represent an innovative approach with the theoretical potential to reduce dengue infections in school children. Objectives: This study took place in the context of a randomised control trial (RCT to test the effectiveness of permethrin-impregnated school uniforms (ISUs for dengue prevention in Chachoengsao Province, Thailand. The objective was to assess the acceptability of ISUs among parents, teachers, and principals of school children involved in the trial. Methodology: Quantitative and qualitative tools were used in a mixed methods approach. Class-clustered randomised samples of school children enrolled in the RCT were selected and their parents completed 321 self-administered questionnaires. Descriptive statistics and logistic regression were used to analyse the quantitative data. Focus group discussions and individual semi-structured interviews were conducted with parents, teachers, and principals. Qualitative data analysis involved content analysis with coding and thematic development. Results: The knowledge and experience of dengue was substantial. The acceptability of ISUs was high. Parents (87.3%; 95% CI 82.9–90.8 would allow their child to wear an ISU and 59.9% (95% CI 53.7–65.9 of parents would incur additional costs for an ISU over a normal uniform. This was significantly associated with the total monthly income of a household and the educational level of the respondent. Parents (62.5%; 95% CI 56.6–68.1 indicated they would be willing to recommend ISUs to other parents. Conclusions: Acceptability of the novel tool of ISUs was high as defined by the lack of concern along with the willingness to pay and recommend. Considering issues of effectiveness and scalability, assessing acceptability of ISUs

  3. Parametric motion control of robotic arms: A biologically based approach using neural networks

    Science.gov (United States)

    Bock, O.; D'Eleuterio, G. M. T.; Lipitkas, J.; Grodski, J. J.

    1993-01-01

    A neural network based system is presented which is able to generate point-to-point movements of robotic manipulators. The foundation of this approach is the use of prototypical control torque signals which are defined by a set of parameters. The parameter set is used for scaling and shaping of these prototypical torque signals to effect a desired outcome of the system. This approach is based on neurophysiological findings that the central nervous system stores generalized cognitive representations of movements called synergies, schemas, or motor programs. It has been proposed that these motor programs may be stored as torque-time functions in central pattern generators which can be scaled with appropriate time and magnitude parameters. The central pattern generators use these parameters to generate stereotypical torque-time profiles, which are then sent to the joint actuators. Hence, only a small number of parameters need to be determined for each point-to-point movement instead of the entire torque-time trajectory. This same principle is implemented for controlling the joint torques of robotic manipulators where a neural network is used to identify the relationship between the task requirements and the torque parameters. Movements are specified by the initial robot position in joint coordinates and the desired final end-effector position in Cartesian coordinates. This information is provided to the neural network which calculates six torque parameters for a two-link system. The prototypical torque profiles (one per joint) are then scaled by those parameters. After appropriate training of the network, our parametric control design allowed the reproduction of a trained set of movements with relatively high accuracy, and the production of previously untrained movements with comparable accuracy. We conclude that our approach was successful in discriminating between trained movements and in generalizing to untrained movements.

  4. Determining optimal corrosion control techniques for small water systems: A unique and systematic approach

    Energy Technology Data Exchange (ETDEWEB)

    Tarallo, S.M.; Beardsley, E. [Camp Dresser & McKee Inc., Povidence, RI (United States); Pytel, D.; Chaplin, T. [Rhode Island Department of Health, Providence, RI (United States)

    1996-11-01

    The Lead and Copper Rule represents one of the most complex rules currently in effect for small water treatment systems. In an effort to attain timely compliance by small systems with limited technical and financial resources, the Rhode Island Department of Health (RIDOH) Division of Drinking Water Quality initiated a study to recommend appropriate corrosion control approaches. The study encompassed three goals: to continue a good compliance record, to help small systems reduce their lead and copper levels, and to avoid unnecessary safety risks to operators and customers.

  5. Novel application of bacteriophage for controlling foaming in wastewater treatment plant- an eco-friendly approach.

    Science.gov (United States)

    Khairnar, Krishna; Chandekar, Rajshree; Nair, Aparna; Pal, Preeti; Paunikar, Waman N

    2016-01-01

    This addendum to "Novel application of bacteriophage for controlling foaming in wastewater treatment plant- an eco-friendly approach " includes characteristics of the phages NOC1, NOC2 and NOC3 not discussed in the previous paper. The phage adsorption and host interaction properties, their sensitivity to pH and temperature are inferred. NOC2 is seen to be more temperature resistant while others are not. All the phages show pH sensitivity. There is a variance observed in the behavior of these phages. Also, applicability of the phage based system to large scale reactors is studied and discussed here. PMID:26890996

  6. Working with "Out-of-Control" Children--A Two-Systems Approach.

    Science.gov (United States)

    Novick, Jack; Novick, Kerry Kelly

    2015-01-01

    The authors apply a two-systems approach to demonstrate improved treatment possibilities and outcomes in this group of children and suggest that psychoanalysis can be defined as a multimodal strengths-based learning experience. Using clinical material from the analysis of an aggressive, "out-of-control" child, they discuss how these behaviors and symptoms are better understood as an actively constructed effort at self-regulation than as a deficiency in capacity or primitive, lagging development. They illustrate how a two-systems framework can allow for an expanded repertoire of techniques and reclaim psychoanalytic concepts that have fallen into disuse. PMID:27337815

  7. Novel application of bacteriophage for controlling foaming in wastewater treatment plant- an eco-friendly approach.

    Science.gov (United States)

    Khairnar, Krishna; Chandekar, Rajshree; Nair, Aparna; Pal, Preeti; Paunikar, Waman N

    2016-01-01

    This addendum to "Novel application of bacteriophage for controlling foaming in wastewater treatment plant- an eco-friendly approach " includes characteristics of the phages NOC1, NOC2 and NOC3 not discussed in the previous paper. The phage adsorption and host interaction properties, their sensitivity to pH and temperature are inferred. NOC2 is seen to be more temperature resistant while others are not. All the phages show pH sensitivity. There is a variance observed in the behavior of these phages. Also, applicability of the phage based system to large scale reactors is studied and discussed here.

  8. Interaction approach to development of control rooms (IDEC). Development of indicators for integrated system validation

    International Nuclear Information System (INIS)

    Integrated evaluation of complex artefacts such as NPP control rooms are claimed to require improved validation approaches. A notion of system usability is introduced. It denotes connecting decisions concerning the appropriateness of artefacts to criteria that indicate the system's ability to fulfil the objectives of the activity system and to promote their appreciation in users' situated actions. System usability is evaluated via an operation-oriented evaluation concept. It includes evaluation of user performance and experienced appropriateness of the system. New types of performance evaluation criteria are introduced. The new indicators and criteria may be derived with the aid of a Core-Task Analysis modeling process. (orig.)

  9. A New Approach in Teaching Power Electronics Control of Electrical Drives using Real-Time

    DEFF Research Database (Denmark)

    Teodorescu, Remus; Bech, Michael Møller; Blaabjerg, Frede;

    2000-01-01

    A new approach in teaching power electronics and electrical drives is achieved at the Flexible Drives System Laboratory (FDSL) from Aalborg University by using the new Total Development Environment (TDE) concept that allows a full visual block-oriented programming of dynamic real-time systems to ...... to be done using the Matlab/Simulink environment. Basics in Electrical Drives and Advanced Control of PWM Inverter Fed Induction Machines courses are succesfully using the new facility and an increased student enrollment is expected in the next coming years....

  10. AN OVERVIEW ON VARIOUS APPROACHES TO ORAL CONTROLLED DRUG DELIVERY SYSTEM VIA GASTRORETENTIVE DRUG DELIVERY SYSTEM

    Directory of Open Access Journals (Sweden)

    Bhalla.Neetika

    2012-04-01

    Full Text Available In recent years scientific and technological advancements have been made in the research and development of oral drug delivery system. Oral sustained drug delivery system is complicated by limited gastric residence times (GRTs. In order to understand various physiological difficulties to achieve gastric retention, we have summarized important factors controlling gastric retention. To overcome these limitations, various approaches have been proposed to increase gastric residence of drug delivery systems in the upper part of the gastrointestinal tract includes floating drug dosage systems (FDDS, swelling or expanding systems , mucoadhesive systems , magnetic systems, modified-shape systems, high density system and other delayed gastric emptying devices.

  11. Evaluating an ensemble classification approach for crop diversityverification in Danish greening subsidy control

    DEFF Research Database (Denmark)

    Chellasamy, Menaka; Ferre, Ty; Greve, Mogens Humlekrog

    2016-01-01

    ’ declarations to war-rant greening payments under the new crop diversification rules. Remote Sensing (RS) technology has been used since 1992 to control farmers’ subsidies in Denmark. However, a proper RS-based approach is yet to be finalised to validate new crop diversity requirements designed for assessing...... and early summer) WorldView-2 imagery (WV2) and includes the following steps: (1) automatic computation of pixel-based prediction probabilities using multiple neural networks; (2) quantification of the classification uncertainty using Endorsement Theory (ET); (3) discrimination of crop pixels and validation...

  12. Landing of VTOL UAVs Using a Stationary Robot Manipulator: A New Approach for Coordinated Control

    OpenAIRE

    Maier, Moritz; Kondak, Konstantin

    2015-01-01

    This paper deals with the landing of VTOL UAVs under severe conditions. We present a novel system based on a robot manipulator, which is used to support a UAV in the last, most challenging, landing phase. In this phase, the aerial vehicle is connected to the robot by means of a universal hinge. This allows to decouple the UAV’s orientation from the robot’s end-effector orientation. The main contribution of the paper is a new control approach for the whole system compos...

  13. A Wind Power and Load Prediction Based Frequency Control Approach for Wind-Diesel-Battery Hybrid Power System

    Directory of Open Access Journals (Sweden)

    Chao Peng

    2015-01-01

    Full Text Available A frequency control approach based on wind power and load power prediction information is proposed for wind-diesel-battery hybrid power system (WDBHPS. To maintain the frequency stability by wind power and diesel generation as much as possible, a fuzzy control theory based wind and diesel power control module is designed according to wind power and load prediction information. To compensate frequency fluctuation in real time and enhance system disturbance rejection ability, a battery energy storage system real-time control module is designed based on ADRC (active disturbance rejection control. The simulation experiment results demonstrate that the proposed approach has a better disturbance rejection ability and frequency control performance compared with the traditional droop control approach.

  14. A Systematic Approach to Identify Candidate Transcription Factors that Control Cell Identity

    Directory of Open Access Journals (Sweden)

    Ana C. D’Alessio

    2015-11-01

    Full Text Available Hundreds of transcription factors (TFs are expressed in each cell type, but cell identity can be induced through the activity of just a small number of core TFs. Systematic identification of these core TFs for a wide variety of cell types is currently lacking and would establish a foundation for understanding the transcriptional control of cell identity in development, disease, and cell-based therapy. Here, we describe a computational approach that generates an atlas of candidate core TFs for a broad spectrum of human cells. The potential impact of the atlas was demonstrated via cellular reprogramming efforts where candidate core TFs proved capable of converting human fibroblasts to retinal pigment epithelial-like cells. These results suggest that candidate core TFs from the atlas will prove a useful starting point for studying transcriptional control of cell identity and reprogramming in many human cell types.

  15. State-Feedback H∞ Control for LPV System Using T-S Fuzzy Linearization Approach

    Directory of Open Access Journals (Sweden)

    Jizhen Liu

    2013-01-01

    ability of the novelly developed T-S fuzzy modeling procedure is established. Consequently, the LPV T-S fuzzy system is obtained which can approximate the ANPV system with required accuracy. Secondly, the notion of piecewise parameter-dependent Lyapunov function is introduced, and then the stabilization problem and the state-feedback H∞ control problem of the LPV T-S fuzzy system are studied. The sufficient conditions are given in linear matrix inequalities (LMIs form. Finally, a numerical example is provided to demonstrate the availability of the above approaches. The simulation results show the high approximation accuracy of the LPV T-S fuzzy system to the ANPV system and the effectiveness of the LPV T-S fuzzy gain scheduling control.

  16. An Islanding Microgrid Power Sharing Approach Using Enhanced Virtual Impedance Control Scheme

    DEFF Research Database (Denmark)

    He, Jinwei; Li, Yun Wei; Guerrero, Josep M.;

    2013-01-01

    In order to address the load sharing problem in islanding microgrids, this paper proposes an enhanced distributed generation (DG) unit virtual impedance control approach. The proposed method can realize accurate regulation of DG unit equivalent impedance at both fundamental and selected harmonic...... frequencies. In contrast to conventional virtual impedance control methods, where only a line current feed-forward term is added to the DG voltage reference, the proposed virtual impedance at fundamental and harmonic frequencies is regulated using DG line current and point of common coupling (PCC) voltage...... feed-forward terms, respectively. With this modification, the impacts of mismatched physical feeder impedances are compensated. Thus, better reactive and harmonic power sharing can be realized. Additionally, this paper also demonstrates that PCC harmonic voltages can be mitigated by reducing...

  17. Contemporary approaches to control system specification and design applied to KAON

    International Nuclear Information System (INIS)

    Large data acquisition and control systems have evolved from early centralized computer systems to become multi-processor, distributed systems. While the complexity of these systems has increased the ability to reliably manage their construction has not kept pace. Structured Analysis and Real-time Structured Analysis have been used successfully to specify systems but, from a project management viewpoint, both lead to different classes of problems during implementation and maintenance. The KAON Factory central control system study employed a uniform approach to requirements analysis and architectural design. The methodology was based on well established object-oriented principles and was free of the problems inherent in the older methodologies. The methodology is presently being used to implement two systems at TRIUMF

  18. A simple approach to eliminate background signals in dynamic control rod reactivity measurements for LWRs

    Energy Technology Data Exchange (ETDEWEB)

    Lee, E. K.; Woo, I. T.; Shin, H. C.; Ryu, S. J.; Bae, S. M. [Korea Electric Power Research Institute, Taejon (Korea, Republic of)

    2003-07-01

    Dynamic rod worth measurement (DRWM{sup TM}) methodology commercialized by Westinghouse was successfully applied to many nuclear power plants in USA to measure the control rod worth at Low Power Physics Tests. But in Korea, to increase the capacity of nuclear power plant, KEPRI has developed Dynamic Control rod Reactivity Measurement (DCRM) system using more rapid and sophisticated reactivity measurement methodology without the change of boron concentration. The object of this paper is to consider the practical method to eliminate background signals from measured ex-core detector signals. Because of relatively low rod insertion speed (40 {approx} 48 steps/min), the background signals affect the final results severely. Therefore a simple and practical method based on the behavior of integral rod worth curve was developed and applied. A total of 26 experimental results show that the proposed approach works to figure out the background signals.

  19. Robust control of uncertain dynamic systems a linear state space approach

    CERN Document Server

    Yedavalli, Rama K

    2014-01-01

    This textbook aims to provide a clear understanding of the various tools of analysis and design for robust stability and performance of uncertain dynamic systems. In model-based control design and analysis, mathematical models can never completely represent the “real world” system that is being modeled, and thus it is imperative to incorporate and accommodate a level of uncertainty into the models. This book directly addresses these issues from a deterministic uncertainty viewpoint and focuses on the interval parameter characterization of uncertain systems. Various tools of analysis and design are presented in a consolidated manner. This volume fills a current gap in published works by explicitly addressing the subject of control of dynamic systems from linear state space framework, namely using a time-domain, matrix-theory based approach. This book also: Presents and formulates the robustness problem in a linear state space model framework Illustrates various systems level methodologies with examples and...

  20. Impacts of reforestation approaches on runoff control in the hilly red soil region of Southern China

    Science.gov (United States)

    Zheng, Hua; Chen, Falin; Ouyang, Zhiyun; Tu, Naimei; Xu, Weihua; Wang, Xiaoke; Miao, Hong; Li, Xiquan; Tian, Yuxin

    2008-07-01

    SummaryVegetation structure and soil properties are not only correlated with forest management practices, but also affect soil and water loss significantly. To estimate the long-term influences of regenerating forest cover on soil and water loss from degraded land, the runoff and soil loss in the context of different forest restoration approaches, including a control plot (CL) and plantations of slash pine (Pinus elliottii), Chinese fir (Cunninghamia lanceolata), tea-oil camellia (Camellia oleifera), and natural secondary forest, were monitored in runoff plots over a 4-year period (2000-2003) in a hilly red soil region in Southern China. Relevant ecological factors and management intensity, were also measured. The results indicated that the four forest restoration approaches decreased surface runoff by 63.0-88.1% and soil erosion by 75.5-97.1% compared to the control. Moreover, runoff and soil erosion in tea-camellia plantation (TCP) and natural secondary forest (NSF) plots were significantly lower than with other treatments. Canopy cover, litter fall, plant roots, plant life forms, soil properties, and vegetation structure are important ecological factors that determine the magnitude of soil loss. Vegetation structure and plant life forms are the main factors reducing surface runoff and the movement of sediments. Effective control of soil and water loss in NSF and TCP are closely related to multiply stratified communities and the presence of specific plant life forms (the herbaceous keystone species Dicranopteris linearis), respectively. In addition, the above mentioned factors were sensitive to forest management patterns, including improper mechanical cultivation. Management practices should attempt to minimize disturbances to these factors to control runoff and soil erosion in each forest management unit. In particular, mechanical cultivation should loosen the soil around the base of a tree only, instead of over the entire ground surface, in the early stages of

  1. Tsetse flies: their biology and control using area-wide integrated pest management approaches.

    Science.gov (United States)

    Vreysen, Marc J B; Seck, Momar Talla; Sall, Baba; Bouyer, Jérémy

    2013-03-01

    Tsetse flies are the cyclical vectors of trypanosomes, the causative agents of 'sleeping sickness' or human African trypanosomosis (HAT) in humans and 'nagana' or African animal trypanosomosis (AAT) in livestock in Sub-saharan Africa. Many consider HAT as one of the major neglected tropical diseases and AAT as the single greatest health constraint to increased livestock production. This review provides some background information on the taxonomy of tsetse flies, their unique way of reproduction (adenotrophic viviparity) making the adult stage the only one easily accessible for control, and how their ecological affinities, their distribution and population dynamics influence and dictate control efforts. The paper likewise reviews four control tactics (sequential aerosol technique, stationary attractive devices, live bait technique and the sterile insect technique) that are currently accepted as friendly to the environment, and describes their limitations and advantages and how they can best be put to practise in an IPM context. The paper discusses the different strategies for tsetse control i.e. localised versus area-wide and focusses thereafter on the principles of area-wide integrated pest management (AW-IPM) and the phased-conditional approach with the tsetse project in Senegal as a recent example. We argue that sustainable tsetse-free zones can be created on Africa mainland provided certain managerial and technical prerequisites are in place.

  2. A policy iteration approach to online optimal control of continuous-time constrained-input systems.

    Science.gov (United States)

    Modares, Hamidreza; Naghibi Sistani, Mohammad-Bagher; Lewis, Frank L

    2013-09-01

    This paper is an effort towards developing an online learning algorithm to find the optimal control solution for continuous-time (CT) systems subject to input constraints. The proposed method is based on the policy iteration (PI) technique which has recently evolved as a major technique for solving optimal control problems. Although a number of online PI algorithms have been developed for CT systems, none of them take into account the input constraints caused by actuator saturation. In practice, however, ignoring these constraints leads to performance degradation or even system instability. In this paper, to deal with the input constraints, a suitable nonquadratic functional is employed to encode the constraints into the optimization formulation. Then, the proposed PI algorithm is implemented on an actor-critic structure to solve the Hamilton-Jacobi-Bellman (HJB) equation associated with this nonquadratic cost functional in an online fashion. That is, two coupled neural network (NN) approximators, namely an actor and a critic are tuned online and simultaneously for approximating the associated HJB solution and computing the optimal control policy. The critic is used to evaluate the cost associated with the current policy, while the actor is used to find an improved policy based on information provided by the critic. Convergence to a close approximation of the HJB solution as well as stability of the proposed feedback control law are shown. Simulation results of the proposed method on a nonlinear CT system illustrate the effectiveness of the proposed approach. PMID:23706414

  3. Molecular biological approaches to the study of vectors in relation to malaria control

    Directory of Open Access Journals (Sweden)

    J. M. Crampton

    1992-01-01

    Full Text Available To a large extent, control of malaria vectors relies on the elimination of breeding sites and the application of chemical agents. There are increasing problems associated with the use of synthetic insecticides for vector control, including the evolution of resistance, the high cost of developing and registering new insecticides and an awareness of pollution from insecticide residues. These factors have stimulated interest in the application of molecular biology to the study of mosquito vectors of malaria; focussing primarily on two aspects. First, the improvement of existing control measures through the development of simplified DNA probe systems suitable for identification of vectors of malaria. The development of synthetic, non-radioactive DNA probes suitable for identification of species in the Anopheles gambiae complex is described with the aim of defining a simplified methodology wich is suitable for entomologist in the field. The second aspect to be considered is the development of completely novel strategies through the development of completely novel strategies through the genetic manipulation of insect vectors of malaria in order to alter their ability to transmit the disease. The major requirements for producing transgenic mosquitoes are outlined together with the progress wich has been made to date and discussed in relation to the prospects which this type of approach has for the future control of malaria.

  4. Control/structure optimization approach for minimum-time reconfiguration of tensegrity systems

    Science.gov (United States)

    Aldrich, Jack B.; Skelton, Robert E.

    2003-07-01

    For a new class of tendon-driven robotic systems that is generalized to include tensegrity structures, this paper focuses on a method to jointly optimize the control law and the structural complexity for a given point-to-point maneuvering task. By fixing external geometry, the number of identical stages within the domain is varied until a minimal mass design is achieved. For the deployment phase, a new method is introduced which determines the tendon force inputs from a set of admissible, non-saturating inputs, that will reconfigure each kinematically invertible unit along its own path in minimum time. The approach utilizes the existence conditions and solution of a linear algebra problem that describe how the set of admissible tendon forces is mapped onto the set of path-dependent torques. Since this mapping is not one-to-one, free parameters in the control law always exist. An infinity-norm minimization with respect to these free parameters is responsible for saturation avoidance. In addition to the required time to deploy, the expended control energy during the post-movement phase is also minimized with respect to the total number of stages. Conditions under which these independent minimizations yield the same robot illustrate the importance of considering control/structure interaction within this new robotics paradigm.

  5. A Systematic Approach for Dynamic Security Assessment and the Corresponding Preventive Control Scheme Based on Decision Trees

    DEFF Research Database (Denmark)

    Liu, Leo; Sun, Kai; Rather, Zakir Hussain;

    2014-01-01

    This paper proposes a decision tree (DT)-based systematic approach for cooperative online power system dynamic security assessment (DSA) and preventive control. This approach adopts a new methodology that trains two contingency-oriented DTs on a daily basis by the databases generated from power......-effective algorithm is adopted in this proposed approach to optimize the trajectory of preventive control. The paper also proposes an importance sampling algorithm on database preparation for efficient DT training for power systems with high penetration of wind power and distributed generation. The performance...... of the approach is demonstrated on a 400-bus, 200-line operational model of western Danish power system....

  6. Proto-object based rate control for JPEG2000: an approach to content-based scalability.

    Science.gov (United States)

    Xue, Jianru; Li, Ce; Zheng, Nanning

    2011-04-01

    The JPEG2000 system provides scalability with respect to quality, resolution and color component in the transfer of images. However, scalability with respect to semantic content is still lacking. We propose a biologically plausible salient region based bit allocation mechanism within the JPEG2000 codec for the purpose of augmenting scalability with respect to semantic content. First, an input image is segmented into several salient proto-objects (a region that possibly contains a semantically meaningful physical object) and background regions (a region that contains no object of interest) by modeling visual focus of attention on salient proto-objects. Then, a novel rate control scheme distributes a target bit rate to each individual region according to its saliency, and constructs quality layers of proto-objects for the purpose of more precise truncation comparable to original quality layers in the standard. Empirical results show that the suggested approach adds to the JPEG2000 system scalability with respect to content as well as the functionality of selectively encoding, decoding, and manipulation of each individual proto-object in the image, with only some slightly trivial modifications to the JPEG2000 standard. Furthermore, the proposed rate control approach efficiently reduces the computational complexity and memory usage, as well as maintains the high quality of the image to a level comparable to the conventional post-compression rate distortion (PCRD) optimum truncation algorithm for JPEG2000.

  7. A Non-Cooperative Game Theoretical Approach For Power Control In Virtual MIMO Wireless Sensor Network

    Directory of Open Access Journals (Sweden)

    R.Valli

    2010-07-01

    Full Text Available Power management is one of the vital issue in wireless sensor networks, where the lifetime of the networkrelies on battery powered nodes. Transmitting at high power reduces the lifetime of both the nodes andthe network. One efficient way of power management is to control the power at which the nodes transmit.In this paper, a virtual multiple input multiple output wireless sensor network (VMIMO-WSNcommunication architecture is considered and the power control of sensor nodes based on the approachof game theory is formulated. The use of game theory has proliferated, with a broad range of applicationsin wireless sensor networking. Approaches from game theory can be used to optimize node level as wellas network wide performance. The game here is categorized as an incomplete information game, in whichthe nodes do not have complete information about the strategies taken by other nodes. For virtualmultiple input multiple output wireless sensor network architecture considered, the Nash equilibrium isused to decide the optimal power level at which a node needs to transmit, to maximize its utility. Outcomeshows that the game theoretic approach considered for VMIMO-WSN architecture achieves the bestutility, by consuming less power.

  8. Output Tracking Control of Switched Hybrid Systems: A Fliess Functional Expansion Approach

    Directory of Open Access Journals (Sweden)

    Fenghua He

    2013-01-01

    Full Text Available The output tracking problem is investigated for a nonlinear affine system with multiple modes of continuous control inputs. We convert the family of nonlinear affine systems under consideration into a switched hybrid system by introducing a multiple-valued logic variable. The Fliess functional expansion is adopted to express the input and output relationship of the switched hybrid system. The optimal switching control is determined for a multiple-step output tracking performance index. The proposed approach is applied to a multitarget tracking problem for a flight vehicle aiming for one real target with several decoys flying around it in the terminal guidance course. These decoys appear as apparent targets and have to be distinguished with the approaching of the flight vehicle. The guidance problem of one flight vehicle versus multiple apparent targets should be considered if no large miss distance might be caused due to the limitation of the flight vehicle maneuverability. The target orientation at each time interval is determined. Simulation results show the effectiveness of the proposed method.

  9. Reproduction of nearby sources by imposing true interaural differences on a sound field control approach.

    Science.gov (United States)

    Badajoz, Javier; Chang, Ji-Ho; Agerkvist, Finn T

    2015-10-01

    In anechoic conditions, the Interaural Level Difference (ILD) is the most significant auditory cue to judge the distance to a sound source located within 1 m of the listener's head. This is due to the unique characteristics of a point source in its near field, which result in exceptionally high, distance dependent ILDs. When reproducing the sound field of sources located near the head with line or circular arrays of loudspeakers, the reproduced ILDs are generally lower than expected, due to physical limitations. This study presents an approach that combines a sound field reproduction method, known as Pressure Matching (PM), and a binaural control technique. While PM aims at reproducing the incident sound field, the objective of the binaural control technique is to ensure a correct reproduction of interaural differences. The combination of these two approaches gives rise to the following features: (i) an accurate reproduction of ILDs is achieved at the head positions considered by the method, (ii) the ILD variations in the vicinity of those positions are smoothed, thus lowering the ILD error, and (iii) the true wavefront is preserved. Given the properties of the presented method, intended distance and directional perception is expected. PMID:26520320

  10. Integrated software health management for aerospace guidance, navigation, and control systems: A probabilistic reasoning approach

    Science.gov (United States)

    Mbaya, Timmy

    Embedded Aerospace Systems have to perform safety and mission critical operations in a real-time environment where timing and functional correctness are extremely important. Guidance, Navigation, and Control (GN&C) systems substantially rely on complex software interfacing with hardware in real-time; any faults in software or hardware, or their interaction could result in fatal consequences. Integrated Software Health Management (ISWHM) provides an approach for detection and diagnosis of software failures while the software is in operation. The ISWHM approach is based on probabilistic modeling of software and hardware sensors using a Bayesian network. To meet memory and timing constraints of real-time embedded execution, the Bayesian network is compiled into an Arithmetic Circuit, which is used for on-line monitoring. This type of system monitoring, using an ISWHM, provides automated reasoning capabilities that compute diagnoses in a timely manner when failures occur. This reasoning capability enables time-critical mitigating decisions and relieves the human agent from the time-consuming and arduous task of foraging through a multitude of isolated---and often contradictory---diagnosis data. For the purpose of demonstrating the relevance of ISWHM, modeling and reasoning is performed on a simple simulated aerospace system running on a real-time operating system emulator, the OSEK/Trampoline platform. Models for a small satellite and an F-16 fighter jet GN&C (Guidance, Navigation, and Control) system have been implemented. Analysis of the ISWHM is then performed by injecting faults and analyzing the ISWHM's diagnoses.

  11. A Control Chart Approach for Representing and Mining Data Streams with Shape Based Similarity

    Energy Technology Data Exchange (ETDEWEB)

    Omitaomu, Olufemi A [ORNL

    2014-01-01

    The mining of data streams for online condition monitoring is a challenging task in several domains including (electric) power grid system, intelligent manufacturing, and consumer science. Considering a power grid application in which thousands of sensors, called the phasor measurement units, are deployed on the power grid network to continuously collect streams of digital data for real-time situational awareness and system management. Depending on design, each sensor could stream between ten and sixty data samples per second. The myriad of sensory data captured could convey deeper insights about sequence of events in real-time and before major damages are done. However, the timely processing and analysis of these high-velocity and high-volume data streams is a challenge. Hence, a new data processing and transformation approach, based on the concept of control charts, for representing sequence of data streams from sensors is proposed. In addition, an application of the proposed approach for enhancing data mining tasks such as clustering using real-world power grid data streams is presented. The results indicate that the proposed approach is very efficient for data streams storage and manipulation.

  12. A Rule Based Approach to ISS Interior Volume Control and Layout

    Science.gov (United States)

    Peacock, Brian; Maida, Jim; Fitts, David; Dory, Jonathan

    2001-01-01

    Traditional human factors design involves the development of human factors requirements based on a desire to accommodate a certain percentage of the intended user population. As the product is developed human factors evaluation involves comparison between the resulting design and the specifications. Sometimes performance metrics are involved that allow leniency in the design requirements given that the human performance result is satisfactory. Clearly such approaches may work but they give rise to uncertainty and negotiation. An alternative approach is to adopt human factors design rules that articulate a range of each design continuum over which there are varying outcome expectations and interactions with other variables, including time. These rules are based on a consensus of human factors specialists, designers, managers and customers. The International Space Station faces exactly this challenge in interior volume control, which is based on anthropometric, performance and subjective preference criteria. This paper describes the traditional approach and then proposes a rule-based alternative. The proposed rules involve spatial, temporal and importance dimensions. If successful this rule-based concept could be applied to many traditional human factors design variables and could lead to a more effective and efficient contribution of human factors input to the design process.

  13. An Approach to Realizing Process Control for Underground Mining Operations of Mobile Machines.

    Directory of Open Access Journals (Sweden)

    Zhen Song

    Full Text Available The excavation and production in underground mines are complicated processes which consist of many different operations. The process of underground mining is considerably constrained by the geometry and geology of the mine. The various mining operations are normally performed in series at each working face. The delay of a single operation will lead to a domino effect, thus delay the starting time for the next process and the completion time of the entire process. This paper presents a new approach to the process control for underground mining operations, e.g. drilling, bolting, mucking. This approach can estimate the working time and its probability for each operation more efficiently and objectively by improving the existing PERT (Program Evaluation and Review Technique and CPM (Critical Path Method. If the delay of the critical operation (which is on a critical path inevitably affects the productivity of mined ore, the approach can rapidly assign mucking machines new jobs to increase this amount at a maximum level by using a new mucking algorithm under external constraints.

  14. Full quaternion based finite-time cascade attitude control approach via pulse modulation synthesis for a spacecraft.

    Science.gov (United States)

    Mazinan, A H; Pasand, M; Soltani, B

    2015-09-01

    In the aspect of further development of investigations in the area of spacecraft modeling and analysis of the control scheme, a new hybrid finite-time robust three-axis cascade attitude control approach is proposed via pulse modulation synthesis. The full quaternion based control approach proposed here is organized in association with both the inner and the outer closed loops. It is shown that the inner closed loop, which consists of the sliding mode finite-time control approach, the pulse width pulse frequency modulator, the control allocation and finally the dynamics of the spacecraft is realized to track the three-axis referenced commands of the angular velocities. The pulse width pulse frequency modulators are in fact employed in the inner closed loop to accommodate the control signals to a number of on-off thrusters, while the control allocation algorithm provides the commanded firing times for the reaction control thrusters in the overactuated spacecraft. Hereinafter, the outer closed loop, which consists of the proportional linear control approach and the kinematics of the spacecraft is correspondingly designed to deal with the attitude angles that are presented by quaternion vector. It should be noted that the main motivation of the present research is to realize a hybrid control method by using linear and nonlinear terms and to provide a reliable and robust control structure, which is able to track time varying three-axis referenced commands. Subsequently, a stability analysis is presented to verify the performance of the overall proposed cascade attitude control approach. To prove the effectiveness of the presented approach, a thorough investigation is presented compared to a number of recent corresponding benchmarks. PMID:26142216

  15. Non-linear control of variable-speed wind turbines with permanent magnet synchronous generators: a robust backstepping approach

    Science.gov (United States)

    Şeker, Murat; Zergeroğlu, Erkan; Tatlicioğlu, Enver

    2016-01-01

    In this study, a robust backstepping approach for the control problem of the variable-speed wind turbine with a permanent magnet synchronous generator is presented. Specifically, to overcome the negative effects of parametric uncertainties in both mechanical and electrical subsystems, a robust controller with a differentiable compensation term is proposed. The proposed methodology ensures the generator velocity tracking error to uniformly approach a small bound where practical tracking is achieved. Stability of the overall system is ensured by Lyapunov-based arguments. Comparative simulation studies with a standard proportional-integral-type controller are performed to illustrate the effectiveness, feasibility and efficiency of the proposed controller.

  16. COORDINATION IN MULTILEVEL NETWORK-CENTRIC CONTROL SYSTEMS OF REGIONAL SECURITY: APPROACH AND FORMAL MODEL

    Directory of Open Access Journals (Sweden)

    A. V. Masloboev

    2015-01-01

    Full Text Available The paper deals with development of methods and tools for mathematical and computer modeling of the multilevel network-centric control systems of regional security. This research is carried out under development strategy implementation of the Arctic zone of the Russian Federation and national safeguarding for the period before 2020 in the Murmansk region territory. Creation of unified interdepartmental multilevel computer-aided system is proposed intended for decision-making information support and socio-economic security monitoring of the Arctic regions of Russia. The distinctive features of the investigated system class are openness, self-organization, decentralization of management functions and decision-making, weak hierarchy in the decision-making circuit and goal generation capability inside itself. Research techniques include functional-target approach, mathematical apparatus of multilevel hierarchical system theory and principles of network-centric control of distributed systems with pro-active components and variable structure. The work considers network-centric management local decisions coordination problem-solving within the multilevel distributed systems intended for information support of regional security. The coordination problem-solving approach and problem formalization in the multilevel network-centric control systems of regional security have been proposed based on developed multilevel recurrent hierarchical model of regional socio-economic system complex security. The model provides coordination of regional security indexes, optimized by the different elements of multilevel control systems, subject to decentralized decision-making. The model specificity consists in application of functional-target technology and mathematical apparatus of multilevel hierarchical system theory for coordination procedures implementation of the network-centric management local decisions. The work-out and research results can find further

  17. Ocean Current Energy Conversion System in Wallacea Region Using Variable Speed Control Approach

    Directory of Open Access Journals (Sweden)

    Aditya Sukma Nugraha

    2012-03-01

    Full Text Available Ocean Current Energy Conversion System (OCECS is a promising green energy resource in this globe. The Thermohaline circulation data indicates that the Wallacea region has the potential of ocean current energy resources. This paper is aimed to propose research and development of OCECSs to be implemented in the Wallacea region. Firstly, four types of green energy conversion systems extracted from ocean are reviewed. Their advantages and disadvantages are discussed. Secondly, the potential of OCECS in the Wallacea region is described. Third, many types of turbines used for OCECS are reviewed and the turbine type for OCECS is selected to be implemented in the Wallacea region. Fourth, control strategy is proposed.From the work reported in this paper it is concluded that it is appropriate to implement OCECSs using axial flow water turbines in the Wallacea region, and that to maximize energy conversion variable speed control approach is selected together with control of mechanism to move the turbine vertically as well as to rotate the turbine in yaw direction. 

  18. Three Rs Approaches in the Production and Quality Control of Fish Vaccines.

    Science.gov (United States)

    Midtlyng, Paul J; Hendriksen, Coenraad; Balks, Elisabeth; Bruckner, Lukas; Elsken, Lawrence; Evensen, Oystein; Fyrand, Kjetil; Guy, Allison; Halder, Marlies; Hawkins, Penny; Kisen, Gunn; Romstad, Anne Berit; Salonius, Kira; Smith, Patrick; Sneddon, Lynne U

    2011-03-01

    The workshop on Three Rs Approaches in the Production and Quality Control of Fish Vaccines aimed a) to identify animal tests currently stipulated for the production and quality control of fish vaccines and to highlight animal welfare concerns associated with these tests; b) to identify viable options to replace, reduce, and refine animal use for fish vaccine testing; and c) to discuss the way forward and set out how the Three Rs may be implemented without jeopardizing the quality of the vaccines. The workshop participants - experts from academia, regulatory authorities, a scientific animal welfare organization, and the fish vaccine industry - agreed that efforts should be undertaken to replace the vaccination-challenge batch potency testing with tests based on antigen quantification or antibody response tests. Regulatory requirements of questionable scientific value and relevance for the quality of fish vaccines, such as the re-testing of batches produced outside Europe, or the double-dose batch safety test, should be re-considered. As an immediate measure the design of the current animal tests should be evaluated and modified in the light of refinement and reduction, for example, the number of unprotected control fish in vaccination-challenge tests should be reduced to the minimum.

  19. The theological and legal approach of prenatal and preimplantation genetic control

    Directory of Open Access Journals (Sweden)

    George Katsimigas

    2012-04-01

    Full Text Available Aim: The investigation of the theological and legal questions derived from the application of prenatal and preimplantation genetic control on human embryos. Moreover, the review of the European and Greek legislation with regard to the prenatal and preimplantation control. Material and Method: A literature review based on both review and research literature, conducted during the period of 1984-2009, derived from MEDLINE, SCOPUS and ΙΑΤΡΟΤΕΚ databases using as key words Prenatal diagnosis , Bioethics, Orthodox ethics, preimplantation genetic diagnosis, Legislation. Results: The orthodox theology adopts a negative view for the abortion of fetus, which it is considered murder in any stage of growth. The legal approach brought two basic questions a the securing of consent from the examined individual and b the constitutional protection of fetus' life. Conclusions: The orthodox theology, through their teaching places the moral criteria for facing the moral questions derived from the application of prenatal and preimplantation genetic control on human embryos. Also, the Greek citizens need to be informed for all the diagnostic examinations on embryos that should be provided by all public health organizations.

  20. On a mean field game optimal control approach modeling fast exit scenarios in human crowds

    KAUST Repository

    Burger, Martin

    2013-12-01

    The understanding of fast exit and evacuation situations in crowd motion research has received a lot of scientific interest in the last decades. Security issues in larger facilities, like shopping malls, sports centers, or festivals necessitate a better understanding of the major driving forces in crowd dynamics. In this paper we present an optimal control approach modeling fast exit scenarios in pedestrian crowds. The model is formulated in the framework of mean field games and based on a parabolic optimal control problem. We consider the case of a large human crowd trying to exit a room as fast as possible. The motion of every pedestrian is determined by minimizing a cost functional, which depends on his/her position and velocity, the overall density of people, and the time to exit. This microscopic setup leads in a mean-field formulation to a nonlinear macroscopic optimal control problem, which raises challenging questions for the analysis and numerical simulations.We discuss different aspects of the mathematical modeling and illustrate them with various computational results. ©2013 IEEE.

  1. Controlling vibrational cooling with zero-width resonances: An adiabatic Floquet approach

    Science.gov (United States)

    Leclerc, Arnaud; Viennot, David; Jolicard, Georges; Lefebvre, Roland; Atabek, Osman

    2016-10-01

    In molecular photodissociation, some specific combinations of laser parameters (wavelength and intensity) lead to unexpected zero-width resonances (ZWRs) with, in principle, infinite lifetimes. Their potential to induce basic quenching mechanisms has recently been devised in the laser control of vibrational cooling through filtration strategies [O. Atabek et al., Phys. Rev. A 87, 031403(R) (2013), 10.1103/PhysRevA.87.031403]. A full quantum adiabatic control theory based on the adiabatic Floquet Hamiltonian is developed to show how a laser pulse could be envelope-shaped and frequency-chirped so as to protect a given initial vibrational state against dissociation, taking advantage of its continuous transport on the corresponding ZWR all along the pulse duration. As compared with previous control scenarios that actually suffered from nonadiabatic contamination, drastically different and much more efficient filtration goals are achieved. A semiclassical analysis helps us to find and interpret a complete map of ZWRs in the laser parameter plane. In addition, the choice of a given ZWR path, among the complete series identified by the semiclassical approach, turns out to be crucial for the cooling scheme, targeting a single vibrational state population left at the end of the pulse, while all others have almost completely decayed. The illustrative example, which has the potential to be transposed to other diatomics, is Na2 prepared by photoassociation in vibrationally hot but translationally and rotationally cold states.

  2. Design of robust fuzzy controller for ship course-tracking based on RBF network and backstepping approach

    Institute of Scientific and Technical Information of China (English)

    ZHANG Song-tao; REN Guang

    2006-01-01

    This study presents an adaptive fuzzy neural network (FNN) control system for the ship steering autopilot. For the Norrbin ship steering mathematical model with the nonlinear and uncertain dynamic characteristics, an adaptive FNN control system is designed to achieve high-precision track control via the backstepping approach. In the adaptive FNN control system, a FNN backstepping controller is a principal controller which includes a FNN estimator used to estimate the uncertainties, and a robust controller is designed to compensate the shortcoming of the FNN backstepping controller. All adaptive learning algorithms in the adaptive FNN control system are derived from the sense of Lyapunov stability analysis, so that system-tracking stability can be guaranteed in the closed-loop system. The effectiveness of the proposed adaptive FNN control system is verified by simulation results.

  3. Novel Approaches to Implementation of Pumpkin Resistance in Control of Viral Diseases

    Directory of Open Access Journals (Sweden)

    Aleksandra Bulajić

    2010-01-01

    .Genetically modified resistant pumpkins have been among the first successfully developed crops. Genotypes with pathogen derived resistance can already be found in commercially grown pumpkins in some parts of the world, and they have been developed by introducingthe coat protein gene of one, two or all three viruses which are the most frequent,ZYMV, WMV and CMV. Yet, this approach to the control of pumpkin viral diseases is related to possible negative consequences, mostly through the already detected gene transferto wild plants and development of resistant transgenic weeds of unpredictable impact on the environment. Improved host plant genetic resistance to viral infections or biological vectors, developedby conventional or genetic engineering methods, represents the most dynamic and prominent field of research. It is economically and ecologically the most justified approach to the control of pumpkin and other plant diseases caused by viruses non-persistentlytransmitted by aphids.

  4. Economic modelling approaches to cost estimates for the control of carbon dioxide emissions

    NARCIS (Netherlands)

    Zhang, Z.X.; Folmer, H.

    1998-01-01

    This article gives an assessment of the relative strengths and weaknesses of a variety of economic modelling approaches commonly used for cost estimates for limiting carbon emissions, including the ad hoc approach, dynamic optimization approach, input-output approach, macroeconomic approach, computa

  5. Theoretical approaches to control spin dynamics in solid-state nuclear magnetic resonance

    Indian Academy of Sciences (India)

    Eugene Stephane Mananga

    2015-12-01

    This article reviews theoretical approaches for controlling spin dynamics in solid-state nuclear magnetic resonance. We present fundamental theories in the history of NMR, namely, the average Hamiltonian and Floquet theories. We also discuss emerging theories such as the Fer and Floquet-Magnus expansions. These theories allow one to solve the time-dependent Schrodinger equation, which is still the central problem in spin dynamics of solid-state NMR. Examples from the literature that highlight several applications of these theories are presented, and particular attention is paid to numerical integrators and propagator operators. The problem of time propagation calculated with Chebychev expansion and the future development of numerical directions with the Cayley transformation are considered. The bibliography includes 190 references.

  6. Water Pollution Control Legislation in Israel: Understanding Implementation Processes from an Actor-Centered Approach

    Directory of Open Access Journals (Sweden)

    Sharon Hophmayer-Tokich

    2013-09-01

    Full Text Available In the State of Israel, advanced legislation for the management of scarce water resources, including legislation to prevent water pollution, were put in place in the early stages of the State’s formation. Despite that, on-going uncontrolled pollution has deteriorated the quality of water sources for decades, with the main source of pollution being untreated or partially treated domestic wastewater. This has been mainly the result of lack of enforcement of the existing laws. During the 1990s and onwards, a shift to forceful enforcement has been observed and wastewater treatment substantially improved. The paper analyzes the implementation processes of the pollution control legislations (the lack-of and the shift to forceful enforcement based on an actor-centered approach, using the contextual interaction theory.

  7. C/SCSC overview: approach, implementation, use. [Cost/Schedule Control Systems Criteria

    Energy Technology Data Exchange (ETDEWEB)

    Turf, Larry

    1979-01-01

    An overview of the Cost/Schedule Control System Criteria, known as C/SCS or C/S Squared is pesented. In the mid-1960s, several DOD service agencies embarked on a new performance measurement concept to track cost and schedule performance on major DOD programs. The performance measurement concept of C/SCS has expanded from DOD use to the Department of Energy (PMS), NASA (533 reports), and private industry such as shipbuilding, utilities, and construction. This paper describes the C/SCSC with the events leading to the C/SCS requirement, how to approach the requirement, and discusses implementing and using the system. Many government publications, directives, and instructions on the subject are listed in the publication.

  8. Identification of Input Nonlinear Control Autoregressive Systems Using Fractional Signal Processing Approach

    Science.gov (United States)

    Chaudhary, Naveed Ishtiaq; Raja, Muhammad Asif Zahoor; Khan, Junaid Ali; Aslam, Muhammad Saeed

    2013-01-01

    A novel algorithm is developed based on fractional signal processing approach for parameter estimation of input nonlinear control autoregressive (INCAR) models. The design scheme consists of parameterization of INCAR systems to obtain linear-in-parameter models and to use fractional least mean square algorithm (FLMS) for adaptation of unknown parameter vectors. The performance analyses of the proposed scheme are carried out with third-order Volterra least mean square (VLMS) and kernel least mean square (KLMS) algorithms based on convergence to the true values of INCAR systems. It is found that the proposed FLMS algorithm provides most accurate and convergent results than those of VLMS and KLMS under different scenarios and by taking the low-to-high signal-to-noise ratio. PMID:23853538

  9. Identification of Input Nonlinear Control Autoregressive Systems Using Fractional Signal Processing Approach

    Directory of Open Access Journals (Sweden)

    Naveed Ishtiaq Chaudhary

    2013-01-01

    Full Text Available A novel algorithm is developed based on fractional signal processing approach for parameter estimation of input nonlinear control autoregressive (INCAR models. The design scheme consists of parameterization of INCAR systems to obtain linear-in-parameter models and to use fractional least mean square algorithm (FLMS for adaptation of unknown parameter vectors. The performance analyses of the proposed scheme are carried out with third-order Volterra least mean square (VLMS and kernel least mean square (KLMS algorithms based on convergence to the true values of INCAR systems. It is found that the proposed FLMS algorithm provides most accurate and convergent results than those of VLMS and KLMS under different scenarios and by taking the low-to-high signal-to-noise ratio.

  10. A New Approach to Robust Stability Analysis of Sampled-data Control Systems

    Institute of Scientific and Technical Information of China (English)

    WANGGuang-Xiong; LIUYan-Wen; HEZhen; WANGYong-Li

    2005-01-01

    The lifting technique is now the most popular tool for dealing with sampled-data control systems. However, for the robust stability problem the system norm is not preserved by the lifting as expected. And the result is generally conservative under the small gain condition. The reason for the norm difference by the lifting is that the state transition operator in the lifted system is zero in this case. A new approach to the robust stability analysis is proposed. It is to use an equivalent discrete-time uncertainty to replace the continuous-time uncertainty. Then the general discretized method can be used for the robust stability problem, and it is not conservative. Examples are givenin the paper.

  11. Optimal Medium Access Control in Cognitive Radios: A Sequential Design Approach

    CERN Document Server

    Lai, Lifeng; Jiang, Hai; Poor, H Vincent

    2008-01-01

    The design of medium access control protocols for a cognitive user wishing to opportunistically exploit frequency bands within parts of the radio spectrum having multiple bands is considered. In the scenario under consideration, the availability probability of each channel is unknown a priori to the cognitive user. Hence efficient medium access strategies must strike a balance between exploring the availability of channels and exploiting the opportunities identified thus far. Using a sequential design approach, an optimal medium access strategy is derived. To avoid the prohibitive computational complexity of this optimal strategy, a low complexity asymptotically optimal strategy is also developed. The proposed strategy does not require any prior statistical knowledge about the traffic pattern on the different channels.

  12. A new approach to data management and its impact on frequency control requirements

    Science.gov (United States)

    Blanchard, D. L.; Fuchs, A. J.; Chi, A. R.

    1979-01-01

    A new approach to data management consisting of spacecraft and data/information autonomy and its impact on frequency control requirements is presented. An autonomous spacecraft is capable of functioning without external intervention for up to 72 hr by enabling the sensors to make observations, maintaining its health and safety, and by using logical safety modes when anomalies occur. Data/information are made autonomous by associating all relevant ancillary data such as time, position, attitude, and sensor identification with the data/information record of an event onboard the spacecraft. This record is so constructed that the record of the event can be physically identified in a complete and self-contained record that is independent of all other data. All data within a packet will be time tagged to the needed accuracy, and the time markings from packet to packet will be coherent to a UTC time scale.

  13. SCIENTIFIC METHODOLOGICAL APPROACHES TO CREATION OF COMPLEX CONTROL SYSTEM MODEL FOR THE STREAMS OF BUILDING WASTE

    Directory of Open Access Journals (Sweden)

    Tskhovrebov Eduard Stanislavovich

    2015-09-01

    Full Text Available In 2011 in Russia a Strategy of Production Development of Construction Materials and Industrial Housing Construction for the period up to 2020 was approved as one of strategic documents in the sphere of construction. In the process of this strategy development all the needs of construction complex were taken into account in all the spheres of economy, including transport system. The strategy also underlined, that the construction industry is a great basis for use and application in secondary economic turnover of dangerous waste from different production branches. This gives possibility to produce construction products of recycled materials and at the same time to solve the problem of environmental protection. The article considers and analyzes scientific methodological approaches to creation of a model of a complex control system for the streams of building waste in frames of organizing uniform ecologically safe and economically effective complex system of waste treatment in country regions.

  14. Identifying dominant controls on hydrologic parameter transfer from gauged to ungauged catchments: a comparative hydrology approach

    Science.gov (United States)

    Singh, R.; Archfield, S.A.; Wagener, T.

    2014-01-01

    Daily streamflow information is critical for solving various hydrologic problems, though observations of continuous streamflow for model calibration are available at only a small fraction of the world’s rivers. One approach to estimate daily streamflow at an ungauged location is to transfer rainfall–runoff model parameters calibrated at a gauged (donor) catchment to an ungauged (receiver) catchment of interest. Central to this approach is the selection of a hydrologically similar donor. No single metric or set of metrics of hydrologic similarity have been demonstrated to consistently select a suitable donor catchment. We design an experiment to diagnose the dominant controls on successful hydrologic model parameter transfer. We calibrate a lumped rainfall–runoff model to 83 stream gauges across the United States. All locations are USGS reference gauges with minimal human influence. Parameter sets from the calibrated models are then transferred to each of the other catchments and the performance of the transferred parameters is assessed. This transfer experiment is carried out both at the scale of the entire US and then for six geographic regions. We use classification and regression tree (CART) analysis to determine the relationship between catchment similarity and performance of transferred parameters. Similarity is defined using physical/climatic catchment characteristics, as well as streamflow response characteristics (signatures such as baseflow index and runoff ratio). Across the entire US, successful parameter transfer is governed by similarity in elevation and climate, and high similarity in streamflow signatures. Controls vary for different geographic regions though. Geology followed by drainage, topography and climate constitute the dominant similarity metrics in forested eastern mountains and plateaus, whereas agricultural land use relates most strongly with successful parameter transfer in the humid plains.

  15. Identifying dominant controls on hydrologic parameter transfer from gauged to ungauged catchments - A comparative hydrology approach

    Science.gov (United States)

    Singh, R.; Archfield, S. A.; Wagener, T.

    2014-09-01

    Daily streamflow information is critical for solving various hydrologic problems, though observations of continuous streamflow for model calibration are available at only a small fraction of the world's rivers. One approach to estimate daily streamflow at an ungauged location is to transfer rainfall-runoff model parameters calibrated at a gauged (donor) catchment to an ungauged (receiver) catchment of interest. Central to this approach is the selection of a hydrologically similar donor. No single metric or set of metrics of hydrologic similarity have been demonstrated to consistently select a suitable donor catchment. We design an experiment to diagnose the dominant controls on successful hydrologic model parameter transfer. We calibrate a lumped rainfall-runoff model to 83 stream gauges across the United States. All locations are USGS reference gauges with minimal human influence. Parameter sets from the calibrated models are then transferred to each of the other catchments and the performance of the transferred parameters is assessed. This transfer experiment is carried out both at the scale of the entire US and then for six geographic regions. We use classification and regression tree (CART) analysis to determine the relationship between catchment similarity and performance of transferred parameters. Similarity is defined using physical/climatic catchment characteristics, as well as streamflow response characteristics (signatures such as baseflow index and runoff ratio). Across the entire US, successful parameter transfer is governed by similarity in elevation and climate, and high similarity in streamflow signatures. Controls vary for different geographic regions though. Geology followed by drainage, topography and climate constitute the dominant similarity metrics in forested eastern mountains and plateaus, whereas agricultural land use relates most strongly with successful parameter transfer in the humid plains.

  16. Image segmentation for uranium isotopic analysis by SIMS: Combined adaptive thresholding and marker controlled watershed approach

    Energy Technology Data Exchange (ETDEWEB)

    Willingham, David G.; Naes, Benjamin E.; Heasler, Patrick G.; Zimmer, Mindy M.; Barrett, Christopher A.; Addleman, Raymond S.

    2016-05-31

    A novel approach to particle identification and particle isotope ratio determination has been developed for nuclear safeguard applications. This particle search approach combines an adaptive thresholding algorithm and marker-controlled watershed segmentation (MCWS) transform, which improves the secondary ion mass spectrometry (SIMS) isotopic analysis of uranium containing particle populations for nuclear safeguards applications. The Niblack assisted MCWS approach (a.k.a. SEEKER) developed for this work has improved the identification of isotopically unique uranium particles under conditions that have historically presented significant challenges for SIMS image data processing techniques. Particles obtained from five NIST uranium certified reference materials (CRM U129A, U015, U150, U500 and U850) were successfully identified in regions of SIMS image data 1) where a high variability in image intensity existed, 2) where particles were touching or were in close proximity to one another and/or 3) where the magnitude of ion signal for a given region was count limited. Analysis of the isotopic distributions of uranium containing particles identified by SEEKER showed four distinct, accurately identified 235U enrichment distributions, corresponding to the NIST certified 235U/238U isotope ratios for CRM U129A/U015 (not statistically differentiated), U150, U500 and U850. Additionally, comparison of the minor uranium isotope (234U, 235U and 236U) atom percent values verified that, even in the absence of high precision isotope ratio measurements, SEEKER could be used to segment isotopically unique uranium particles from SIMS image data. Although demonstrated specifically for SIMS analysis of uranium containing particles for nuclear safeguards, SEEKER has application in addressing a broad set of image processing challenges.

  17. SY 16-1 DIETARY APPROACHES TO PREVENT AND CONTROL ELEVATED BLOOD PRESSURE.

    Science.gov (United States)

    Park, Yongsoon

    2016-09-01

    A healthy lifestyle is important in CVD prevention and treatment through effects on modifiable CVD risk factors, particularly blood pressure. Although the major drawback is the low level of adherence over time, appropriate lifestyle changes may safely and effectively prevent and treat hypertension. The recommended dietary approaches that have been shown to be capable of reducing blood pressure are: salt restriction, moderation of alcohol consumption, high consumption of vegetables and fruits and low-fat and other types of diet, and weight reduction. There is strong and consistent clinical trial evidence that reducing salt intake to about 5 g/day has a modest (1-2 mmHg) SBP-lowering effect in normotensive individuals and a somewhat more pronounced effect (4-5 mmHg) in hypertensive individuals. Compared with salt restriction alone, the Dietary Approaches to Stop Hypertension (DASH) diet resulted in the greater reduction in blood pressure. The dietary pattern's effect on blood pressure is independent of changes in weight and sodium intake.Dietary pattern such as the DASH dietary pattern, the USDA Food Pattern, or the AHA Diet are higher in fruits (particularly fresh), vegetables (emphasizing root and green varieties), whole grains (cereals, breads, rice, or pasta), and fatty fish (rich in omega-3 fatty acids); lower in red meat (and emphasizing lean meats); substituted lower-fat or fat-free dairy products for higher-fat dairy foods; and used oils (olive or canola), nuts (walnuts, almonds, or hazelnuts) or margarines blended with rapeseed or flaxseed oils in lieu of butter and other fats. This dietary pattern should be adopted to appropriate calorie requirements, personal and cultural food preferences, and nutrition therapy for other medical conditions (including diabetes mellitus). In conclusion, most recent dietary approach to prevent and control elevated blood pressure is combination the DASH dietary pattern with lower sodium intake. PMID:27643264

  18. Occupational exposure to radon progeny: Importance, experience with control, regulatory approaches

    International Nuclear Information System (INIS)

    An overview of possible occupational exposures to enhanced natural radiation in Germany is given, based on an analysis of the German Radiological Protection Commission. So far, the most significant exposure source is radon at underground and above ground workplaces. As a result of relevant regulations, in East Germany since the 70's a systematic monitoring of exposures to radon progeny has been introduced step by step in the uranium industry, in conventional ore mining, in show caves and mines, in enterprises for securing mining areas against subsidence, in radon spas and in water works in radon affected areas. Individual exposures have been assessed. The monitoring results for the period 1975-1998 are presented. Successful protection measures leading to a significant reduction of the exposures are discussed. using workplace monitoring results and registered occupancy times. In West Germany no regulations in this area were in force. Nevertheless, voluntary measuring programmes at similar workplaces were carried out. In case of unacceptable exposures successful protection measures were implemented. At present a systematic approach to control occupational exposures to radon is laid down in the European Directive 96/29/Euratom which has to be taken over in the national legislation to come. The expected number of workplaces to be included in the radiation protection system in Germany, the recommendable way of including different workplace types taking into account appropriate reference levels, and possible approaches to a graded system of workplace and individual monitoring are discussed in detail. (author)

  19. Approaches for controlling illicit tobacco trade--nine countries and the European Union.

    Science.gov (United States)

    Ross, Hana; Husain, Muhammad Jami; Kostova, Deliana; Xu, Xin; Edwards, Sarah M; Chaloupka, Frank J; Ahluwalia, Indu B

    2015-05-29

    An estimated 11.6% of the world cigarette market is illicit, representing more than 650 billion cigarettes a year and $40.5 billion in lost revenue. Illicit tobacco trade refers to any practice related to distributing, selling, or buying tobacco products that is prohibited by law, including tax evasion (sale of tobacco products without payment of applicable taxes), counterfeiting, disguising the origin of products, and smuggling. Illicit trade undermines tobacco prevention and control initiatives by increasing the accessibility and affordability of tobacco products, and reduces government tax revenue streams. The World Health Organization (WHO) Protocol to Eliminate Illicit Trade in Tobacco Products, signed by 54 countries, provides tools for addressing illicit trade through a package of regulatory and governing principles. As of May 2015, only eight countries had ratified or acceded to the illicit trade protocol, with an additional 32 needed for it to become international law (i.e., legally binding). Data from multiple international sources were analyzed to evaluate the 10 most commonly used approaches for addressing illicit trade and to summarize differences in implementation across select countries and the European Union (EU). Although the WHO illicit trade protocol defines shared global standards for addressing illicit trade, countries are guided by their own legal and enforcement frameworks, leading to a diversity of approaches employed across countries. Continued adoption of the methods outlined in the WHO illicit trade protocol might improve the global capacity to reduce illicit trade in tobacco products. PMID:26020137

  20. Preparation of polymers with controlled molecular architecture. A new convergent approach to dendritic macromolecules

    Energy Technology Data Exchange (ETDEWEB)

    Hawker, C.J.; Frechet, J.M.J. (Cornell Univ., Ithaca, NY (USA))

    1990-10-10

    The novel convergent growth approach to topological macromolecules based on dendritic fragments is described. The polyether dendritic fragments are prepared by starting from what will become the periphery of the molecule and progressing inward. In the first step, 2 mol of a benzylic bromide is condensed with the two phenolic groups of the monomer, 3,5-di-hydroxybenzyl alcohol, under phase-transfer conditions. After transformation of the benzylic alcohol functionality of the growing molecule into the corresponding bromide, the procedure is repeated with stepwise addition of the monomer followed again by activation of the benzylic site. After several generations of growth, the resulting dendritic wedges, in their benzylic bromide form, can be coupled to a polyfunctional core such as 1,1,1-tris(4{prime}-hydroxyphenyl)ethane to form the final hyperbranched macromolecule. Unique features of the convergent approach include the control over the nature and placement of the groups that are placed at the periphery of the molecule and the fact that each growth step only involves reaction at a single site of the growing macromolecule.