Pub Date : 2014-05-09DOI: 10.1080/21642583.2014.921585
Manjusha Bhave, S. Janardhanan, L. Dewan
Robotic manipulators are widely used in space endeavors nowadays. For space applications, usually lightweight robotic manipulators are preferred. Hence, the system can be made underactuated intentionally. Also, one or more actuators may fail in space. Therefore, the system is highly uncertain and less actuated. The sliding mode control strategy does not depend on exact knowledge of the system model but chattering in states and control is observed. The present work showcases two different control techniques for achieving finite-time convergence and continuous control. The first technique is to choose a zero-error sliding function with a higher order sliding mode control and the second technique is to use a terminal sliding function with appropriate higher order sliding mode control for tracking control of an underactuated manipulator. A comparison is presented for the same.
{"title":"A finite-time convergent sliding mode control for rigid underactuated robotic manipulator","authors":"Manjusha Bhave, S. Janardhanan, L. Dewan","doi":"10.1080/21642583.2014.921585","DOIUrl":"https://doi.org/10.1080/21642583.2014.921585","url":null,"abstract":"Robotic manipulators are widely used in space endeavors nowadays. For space applications, usually lightweight robotic manipulators are preferred. Hence, the system can be made underactuated intentionally. Also, one or more actuators may fail in space. Therefore, the system is highly uncertain and less actuated. The sliding mode control strategy does not depend on exact knowledge of the system model but chattering in states and control is observed. The present work showcases two different control techniques for achieving finite-time convergence and continuous control. The first technique is to choose a zero-error sliding function with a higher order sliding mode control and the second technique is to use a terminal sliding function with appropriate higher order sliding mode control for tracking control of an underactuated manipulator. A comparison is presented for the same.","PeriodicalId":22127,"journal":{"name":"Systems Science & Control Engineering: An Open Access Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82993583","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-05-09DOI: 10.1080/21642583.2014.913510
M. Arefi, J. Zarei, H. Karimi
In this paper, an adaptive output feedback stabilization method for a class of uncertain nonlinear systems is presented. Since this approach does not require any information about the bound of uncertainties, this information is not needed a priori and a mechanism for its estimation is exploited. The adaptation law is obtained using the Lyapunov direct method. Since all the states are not measurable, an observer is designed to estimate unmeasurable states for stabilization. Therefore, in the design procedure, first an observer is designed and then the control signal is constructed based on the estimated states and adaptation law with the σ-modification algorithm. The uniformly ultimately boundedness of all signals in the closed-loop system is analytically shown using the Lyapunov method. The effectiveness of the proposed scheme is shown by applying to a unified chaotic system.
{"title":"Observer-based adaptive stabilization of a class of uncertain nonlinear systems","authors":"M. Arefi, J. Zarei, H. Karimi","doi":"10.1080/21642583.2014.913510","DOIUrl":"https://doi.org/10.1080/21642583.2014.913510","url":null,"abstract":"In this paper, an adaptive output feedback stabilization method for a class of uncertain nonlinear systems is presented. Since this approach does not require any information about the bound of uncertainties, this information is not needed a priori and a mechanism for its estimation is exploited. The adaptation law is obtained using the Lyapunov direct method. Since all the states are not measurable, an observer is designed to estimate unmeasurable states for stabilization. Therefore, in the design procedure, first an observer is designed and then the control signal is constructed based on the estimated states and adaptation law with the σ-modification algorithm. The uniformly ultimately boundedness of all signals in the closed-loop system is analytically shown using the Lyapunov method. The effectiveness of the proposed scheme is shown by applying to a unified chaotic system.","PeriodicalId":22127,"journal":{"name":"Systems Science & Control Engineering: An Open Access Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89464139","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-05-09DOI: 10.1080/21642583.2014.912571
Arindum Mukhopadhyay, A. Goswami
Government regulations, environmental taxes, media and growing environmental concern among customers have created a need for ecofriendly and economic manufacturing system. Since imperfect products are unavoidable due to faulty production, transport and storage conditions, they must be screened out before delivery to the customer through a 100% screening process which produces reworkable, non-reworkable but slightly defective items and scrap items beside the major perfect items. In manufacturing scenarios the pollutants are the harmful byproducts. Sometimes a small fraction of pollutant remains uncaptured or leaked from the cumulated pollutants. Keeping all these facts in mind, we propose a economic production quantity model with three types of imperfect items as random fractions of production lot-size under two different scenarios namely constant and variable pollution cost. We have illustrated our model by numerical example and sensitivity analysis is also carried out. We have shown that our model can also be used for cap-and-trade policy.
{"title":"Economic production quantity models for imperfect items with pollution costs","authors":"Arindum Mukhopadhyay, A. Goswami","doi":"10.1080/21642583.2014.912571","DOIUrl":"https://doi.org/10.1080/21642583.2014.912571","url":null,"abstract":"Government regulations, environmental taxes, media and growing environmental concern among customers have created a need for ecofriendly and economic manufacturing system. Since imperfect products are unavoidable due to faulty production, transport and storage conditions, they must be screened out before delivery to the customer through a 100% screening process which produces reworkable, non-reworkable but slightly defective items and scrap items beside the major perfect items. In manufacturing scenarios the pollutants are the harmful byproducts. Sometimes a small fraction of pollutant remains uncaptured or leaked from the cumulated pollutants. Keeping all these facts in mind, we propose a economic production quantity model with three types of imperfect items as random fractions of production lot-size under two different scenarios namely constant and variable pollution cost. We have illustrated our model by numerical example and sensitivity analysis is also carried out. We have shown that our model can also be used for cap-and-trade policy.","PeriodicalId":22127,"journal":{"name":"Systems Science & Control Engineering: An Open Access Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79042908","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-05-08DOI: 10.1080/21642583.2014.919888
Yikun Lu, Timo Käkölä
Information and communications technology (ICT)-enabled international sourcing of software-intensive systems and services (eSourcing) is a powerful strategy for managing businesses more effectively. China is becoming a superpower for eSourcing service provisioning, but most Chinese providers are small- or medium-sized and leverage the mediated eSourcing model, delivering services to foreign ICT clients who interface with end-clients onshore. This model restricts the providers to low-value projects. This paper probes eSourcing of software testing services within the Chinese market because testing is one of the best ICT services small- and medium-sized providers can provide to develop domain and technological knowledge required to transcend the limitations of the mediated sourcing model. This paper draws upon a literature review and a case study to create and validate a life-cycle model for the provisioning of software testing services that helps providers to develop the capabilities for overcoming the limitations of mediated sourcing. This model helps clients and providers to dynamically manage the life-cycle, assigns specific responsibilities to the involved roles, and supports the tasks of the roles and the entire life-cycle with a class of integrated requirements, test, and defect management systems. This class is found to be the most important class of information systems for enabling the life-cycle.
{"title":"A dynamic life-cycle model for the provisioning of software testing services","authors":"Yikun Lu, Timo Käkölä","doi":"10.1080/21642583.2014.919888","DOIUrl":"https://doi.org/10.1080/21642583.2014.919888","url":null,"abstract":"Information and communications technology (ICT)-enabled international sourcing of software-intensive systems and services (eSourcing) is a powerful strategy for managing businesses more effectively. China is becoming a superpower for eSourcing service provisioning, but most Chinese providers are small- or medium-sized and leverage the mediated eSourcing model, delivering services to foreign ICT clients who interface with end-clients onshore. This model restricts the providers to low-value projects. This paper probes eSourcing of software testing services within the Chinese market because testing is one of the best ICT services small- and medium-sized providers can provide to develop domain and technological knowledge required to transcend the limitations of the mediated sourcing model. This paper draws upon a literature review and a case study to create and validate a life-cycle model for the provisioning of software testing services that helps providers to develop the capabilities for overcoming the limitations of mediated sourcing. This model helps clients and providers to dynamically manage the life-cycle, assigns specific responsibilities to the involved roles, and supports the tasks of the roles and the entire life-cycle with a class of integrated requirements, test, and defect management systems. This class is found to be the most important class of information systems for enabling the life-cycle.","PeriodicalId":22127,"journal":{"name":"Systems Science & Control Engineering: An Open Access Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73763011","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-05-08DOI: 10.1080/21642583.2014.919887
Saeed Radhoush, M. Samavat, M. Vali
This paper extends the application of continuous Chebyshev wavelet expansions to find the optimal solution of linear time-varying systems using two different approaches. By using the product of two time functions together with the operational matrix of integration, the system of state equations are changed into a set of algebraic equations which can be solved using a digital computer. In addition, the Chebyshev wavelets are more successful to find the optimal solution of linear time-varying systems when compared with the other existing mentioned algorithms. Finally, the main feature of this paper over similar possible works is that the use of the Lagrange multipliers approach gives more accurate results in comparison with the results of the Riccati approach. The given examples support these claims.
{"title":"Optimal control of linear time-varying systems using the Chebyshev wavelets (a comparative approach)","authors":"Saeed Radhoush, M. Samavat, M. Vali","doi":"10.1080/21642583.2014.919887","DOIUrl":"https://doi.org/10.1080/21642583.2014.919887","url":null,"abstract":"This paper extends the application of continuous Chebyshev wavelet expansions to find the optimal solution of linear time-varying systems using two different approaches. By using the product of two time functions together with the operational matrix of integration, the system of state equations are changed into a set of algebraic equations which can be solved using a digital computer. In addition, the Chebyshev wavelets are more successful to find the optimal solution of linear time-varying systems when compared with the other existing mentioned algorithms. Finally, the main feature of this paper over similar possible works is that the use of the Lagrange multipliers approach gives more accurate results in comparison with the results of the Riccati approach. The given examples support these claims.","PeriodicalId":22127,"journal":{"name":"Systems Science & Control Engineering: An Open Access Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82029068","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-05-07DOI: 10.1080/21642583.2014.920281
S. Khadraoui, H. Nounou, M. Nounou, A. Datta, S. Bhattacharyya
This paper addresses the control design problem for unknown linear single-input single-output systems using a set of measurements. In standard control methods, controllers are designed on the basis of a mathematical model. Such a mathematical model, which describes the behavior of the system, can be developed using either physical laws or measured data. However, due to the complex dynamics of many physical systems, some prior assumptions are usually made to build simplified models. The efficacy of such model-based control techniques depends greatly on the quality of models used. Hence, data-based control design methods appeared as an alternative to model-based methods. Such data-based techniques are powerful in the sense that no mathematical model is needed for controller design. In this paper, we propose an approach that uses frequency response data to directly design controllers without going through any modeling stage. The main idea of our proposed method is to design polynomial RST controllers, for which the closed-loop frequency response fits a desired frequency response that describes some desired performance specifications. This problem is formulated as an error minimization problem, which can be solved using efficient optimization algorithms. The main feature of our proposed control approach is that it enables the designer to pre-select the controller structure, which allows the design of low-order controllers. Moreover, this control design approach does not depend on the increasing order and complexity of the system. An application to water level control of a coupled tank system is presented to validate and illustrate the efficacy of the proposed approach.
{"title":"A measurement-based technique for designing fixed-order RST controllers and application to a coupled water tank system","authors":"S. Khadraoui, H. Nounou, M. Nounou, A. Datta, S. Bhattacharyya","doi":"10.1080/21642583.2014.920281","DOIUrl":"https://doi.org/10.1080/21642583.2014.920281","url":null,"abstract":"This paper addresses the control design problem for unknown linear single-input single-output systems using a set of measurements. In standard control methods, controllers are designed on the basis of a mathematical model. Such a mathematical model, which describes the behavior of the system, can be developed using either physical laws or measured data. However, due to the complex dynamics of many physical systems, some prior assumptions are usually made to build simplified models. The efficacy of such model-based control techniques depends greatly on the quality of models used. Hence, data-based control design methods appeared as an alternative to model-based methods. Such data-based techniques are powerful in the sense that no mathematical model is needed for controller design. In this paper, we propose an approach that uses frequency response data to directly design controllers without going through any modeling stage. The main idea of our proposed method is to design polynomial RST controllers, for which the closed-loop frequency response fits a desired frequency response that describes some desired performance specifications. This problem is formulated as an error minimization problem, which can be solved using efficient optimization algorithms. The main feature of our proposed control approach is that it enables the designer to pre-select the controller structure, which allows the design of low-order controllers. Moreover, this control design approach does not depend on the increasing order and complexity of the system. An application to water level control of a coupled tank system is presented to validate and illustrate the efficacy of the proposed approach.","PeriodicalId":22127,"journal":{"name":"Systems Science & Control Engineering: An Open Access Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83780167","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-04-30DOI: 10.1080/21642583.2014.883108
B. Munyazikwiye, K. Robbersmyr, H. Karimi
In this paper a state-space estimation procedure that relies on the time-domain analysis of input and output signals is used for mathematical modeling of vehicle frontal crash. The model is a double-spring–mass–damper system, whereby the front mass and real mass represent the chassis and the passenger compartment, respectively. It is observed that the dynamic crash of the model is closer to the dynamic crash from experimental when the mass of the chassis is greater than the mass of the passenger compartment. The dynamic crash depends on pole placement and the estimated parameters. It is noted that when the poles of the model are closer to zero, the dynamic crash of the model is far from the dynamic crash from the experimental data. The stiffness and damping coefficients play an important role in the dynamic crash.
{"title":"A state-space approach to mathematical modeling and parameters identification of vehicle frontal crash","authors":"B. Munyazikwiye, K. Robbersmyr, H. Karimi","doi":"10.1080/21642583.2014.883108","DOIUrl":"https://doi.org/10.1080/21642583.2014.883108","url":null,"abstract":"In this paper a state-space estimation procedure that relies on the time-domain analysis of input and output signals is used for mathematical modeling of vehicle frontal crash. The model is a double-spring–mass–damper system, whereby the front mass and real mass represent the chassis and the passenger compartment, respectively. It is observed that the dynamic crash of the model is closer to the dynamic crash from experimental when the mass of the chassis is greater than the mass of the passenger compartment. The dynamic crash depends on pole placement and the estimated parameters. It is noted that when the poles of the model are closer to zero, the dynamic crash of the model is far from the dynamic crash from the experimental data. The stiffness and damping coefficients play an important role in the dynamic crash.","PeriodicalId":22127,"journal":{"name":"Systems Science & Control Engineering: An Open Access Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84655512","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-04-28DOI: 10.1080/21642583.2014.906004
N. S. Patil, S. Sharma
The standard approaches to analyse the Itô stochastic differential system are the Fokker–Planck equation and multi-dimensional Itô differential rule. In contrast to the Itô stochastic differential system, this paper develops a mathematical theory of a coloured noise process-driven stochastic differential system. More precisely, the coloured noise process-driven stochastic differential equation x˙t=f(xt)+g(xt) ξt is the subject of investigations. The statistical properties of the input noise process ξt are stationary and finite, non-zero, relatively smaller correlation time. The notion of “stochastic equivalence” coupled with stochastic differential rule plays the key role to develop the theory of this paper. The theory of the paper will be of use to analysing and control of dynamical systems embedded in the coloured noise environment.
{"title":"A prediction theory for a coloured noise-driven stochastic differential system","authors":"N. S. Patil, S. Sharma","doi":"10.1080/21642583.2014.906004","DOIUrl":"https://doi.org/10.1080/21642583.2014.906004","url":null,"abstract":"The standard approaches to analyse the Itô stochastic differential system are the Fokker–Planck equation and multi-dimensional Itô differential rule. In contrast to the Itô stochastic differential system, this paper develops a mathematical theory of a coloured noise process-driven stochastic differential system. More precisely, the coloured noise process-driven stochastic differential equation x˙t=f(xt)+g(xt) ξt is the subject of investigations. The statistical properties of the input noise process ξt are stationary and finite, non-zero, relatively smaller correlation time. The notion of “stochastic equivalence” coupled with stochastic differential rule plays the key role to develop the theory of this paper. The theory of the paper will be of use to analysing and control of dynamical systems embedded in the coloured noise environment.","PeriodicalId":22127,"journal":{"name":"Systems Science & Control Engineering: An Open Access Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82420578","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-04-17DOI: 10.1080/21642583.2014.895969
G. Kumar, Krishan Kumar
Network security is a specialized field consisting of the provisions and policies to prevent and monitor unauthorized access, misuse, modification, or denial of a computer network and network-accessible resources as well as ensuring their availability through proper procedures. Many security devices are being developed and deployed to defend against cyber threats and to prevent unintended data breaches. In spite of all these efforts, the ‘golden age’ of cyber crime continues, as organizations around the world continue to suffer data breaches and security attacks. What kinds of threats we are facing today? How these threats are to be dealt with? The goal of this paper is to communicate an updated perspective of network security for organizations, and researchers in the field and present some recommendations to tackle the current situation of security threats.
{"title":"Network security – an updated perspective","authors":"G. Kumar, Krishan Kumar","doi":"10.1080/21642583.2014.895969","DOIUrl":"https://doi.org/10.1080/21642583.2014.895969","url":null,"abstract":"Network security is a specialized field consisting of the provisions and policies to prevent and monitor unauthorized access, misuse, modification, or denial of a computer network and network-accessible resources as well as ensuring their availability through proper procedures. Many security devices are being developed and deployed to defend against cyber threats and to prevent unintended data breaches. In spite of all these efforts, the ‘golden age’ of cyber crime continues, as organizations around the world continue to suffer data breaches and security attacks. What kinds of threats we are facing today? How these threats are to be dealt with? The goal of this paper is to communicate an updated perspective of network security for organizations, and researchers in the field and present some recommendations to tackle the current situation of security threats.","PeriodicalId":22127,"journal":{"name":"Systems Science & Control Engineering: An Open Access Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91485426","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-04-17DOI: 10.1080/21642583.2014.900657
M. Darouach, H. S. Ali
The functional filtering problem is solved in the frequency domain. From the recently obtained time-domain results, a simple frequency optimal filter is obtained and its design is solved by the spectral factorization. Continuous and -time cases are considered. A numerical example is given to illustrate the presented approach.
{"title":"Optimal unbiased functional filtering in the frequency domain","authors":"M. Darouach, H. S. Ali","doi":"10.1080/21642583.2014.900657","DOIUrl":"https://doi.org/10.1080/21642583.2014.900657","url":null,"abstract":"The functional filtering problem is solved in the frequency domain. From the recently obtained time-domain results, a simple frequency optimal filter is obtained and its design is solved by the spectral factorization. Continuous and -time cases are considered. A numerical example is given to illustrate the presented approach.","PeriodicalId":22127,"journal":{"name":"Systems Science & Control Engineering: An Open Access Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80192896","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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