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The purpose of this paper extends the authors’ previous contributions on aircraft system identification, such as open loop identification or closed loop identification, to cascade system identification. Because the cascade system is one special network system, existing in lots of practical engineers, more unknown systems are needed to identify simultaneously within the statistical environment with the probabilistic noises. Consider this problem of cascade system identification, prediction error method is proposed to identify three unknown systems, which are parameterized by three unknown parameter vectors. Then the cascade system identification is transferred as one parameter identification problem, being solved by the online subgradient descent algorithm. Furthermore, the nonparametric estimation is proposed to consider the general case without any parameterized process. To make up the identification mission, model validation process is given to show the asymptotic interval of the identified parameter. Finally, simulation example confirms the proposed theoretical results.

Firstly, aircraft system identification is reviewed through the understanding about system identification and advances in control theory, then cascade system identification is introduced to be one special network system. Secondly, for the problem of cascade system identification, prediction error method and online subgradient decent algorithm are combined together to identify the cascade system with the parameterized systems. Thirdly from the point of more general completeness, another way is proposed to identify the nonparametric estimation, then model validation process is added to complete the whole identification mission.

This cascade system corresponds to one network system, existing in lots of practice, such as aircraft, ship and robot, so it is necessary to identify this cascade system, paving a way for latter network system identification. Parametric and nonparametric estimations are all studied within the statistical environment. Then research on bounded noise is an ongoing work.

To the best of the authors’ knowledge, research on aircraft system identification only concern on open loop and closed loop system identification, no any identification results about network system identification. This paper considers cascade system identification, being one special case on network system identification, so this paper paves a basic way for latter more advanced system identification and control theory.

A structurally constrained discrete state space model is employed as the basis in the development of an identification and control procedure. System excitation is conditioned in accordance with a restricted minimization of a composite cost functional embodying a compromise legitimizing simultaneous identification and control. Alternative scalar measures of the system identified parametric transition matrices are combined with a state quadratic control measure in the composite cost, and an investigation of the effect of a scalar weighting in the functional (offsetting identification with control) considered. Tabular and graphical results are presented covering the likely range of the proposed systems applicability.

The purpose of this paper is to propose an efficient and straightforward approach for system identification of a rotating single link flexible manipulator (RSLFM). Also, the achieved results are experimentally validated through identification procedure.

The proposed system identification approach is applied to a RSLFM with a tip mass. At first, the dynamic model of the system is derived using Lagrange method. Then, an efficient method is developed for identification of such a system. This method facilitates the nonlinear complicated identification problem of the RSLFM to a simplified root finding problem.

The main advantage of the developed method is to convert a complicated system identification process to a simple nonlinear equation solution. This approach uses small-size input/output data set and requires a short-time interval of data acquisition, which gives important advantages in lower computational load and lower execution time. The investigated approach is studied on experimental system identification of a single link flexible manipulator. To demonstrate this fact, the developed method is successfully applied in identification of two other mechanical systems; the inverted pendulum on a cart and the ball and beam apparatus.

In this work, the proposed identification approach has been originally applied to a RSLFM and two other mechanical examples. All obtained identification results show the performance and applicability of the developed method clearly. This approach is not restricted in using state space or transfer function. It has significant superiority in comparison with other known approaches including autoregressive with exogenous input (ARX) and Box-Jenkins (BJ).

The purpose of this study is to propose a conceptual structural equation model to, first, investigate the relationships among knowledge management (KM) system quality, employees' self‐perceived social identification, trust at workplace as well as online knowledge sharing behaviors, and, second, demonstrate the direct and indirect effect of social identification and trust at workplace on online knowledge sharing from the perspective of KM system quality.

A questionnaire was distributed to 437 full‐time employees (n=437) from three technology companies in Taiwan. These companies have had years of experience in implementing KM systems. Data were analyzed by employing structural equation modeling.

The results show that: social identification and trust at workplace have a mediating effect on online knowledge sharing within organizations; trust at workplace is the stronger mediator than social identification; social identification has a positive and significant impact on trust at workplace; and there is significant correlation between KM system quality and social identification as well as trust.

Based on these findings, organizations in Taiwan that aim to maximize the effectiveness and efficiency of KM systems should find ways to enhance employees' self‐awareness on social identification and trust in the workplace.

The conceptual model provides useful information for managers to enhance knowledge sharing through the formation of social identification and promotion of trust at workplaces.

The purpose of this paper is to identify the fault modes of a nonlinear twin-rotor system (TRS) using the subspace technique to facilitate fault identification, diagnosis and control applications.

For identification of fault modes, three types of system malfunctions are introduced. First malfunction resembles actuator, second internal system dynamics and third represents sensor malfunction or offset. For each fault scenario, the resulting TRS model is applied with persistently exciting inputs and corresponding outputs are recorded. The collected input–output data are invoked in NS4SID subspace system identification algorithm to obtain the unknown fault model. The identified actuator fault modes of the TRS can be used for fault diagnostics, fault isolation or fault correction applications.

The identified models obtained through system identification are validated for correctness by comparing the response of the actual model under the fault condition and identified model. The results certify that the identified fault modes correctly resemble the respective fault conditions in the actual system.

The utilization of proposed work for current research emphasized the area of fault detection, diagnosis and correction applications that makes its value significantly. These modes when used for diagnosis purposes allow users to timely get intimated and rectify the performance degradation of the plant before it gets totally malfunctioned. Moreover, the slight performance degradation is also indicated when fault diagnosis is performed.

An identification scheme to identify interconnected discrete-time (DT) varying systems.

The purpose of this paper is the identification of interconnected discrete time varying systems. The proposed technique permits the division of global system to many subsystems by building a vector observation of each subsystem and then using the gradient method to identify the time-varying parameters of each subsystem. The convergence of the presented algorithm is proven under a given condition.

The effectiveness of the proposed technique is then shown with application to a simulation example.

In the past decade, there has been a renewed interest in interconnected systems that are multidimensional and composed of similar subsystems, which interact with their closest neighbors. In this context, the concept of parametric identification of interconnected systems becomes relevant, as it considers the estimation problem of such systems. Therefore, the identification of interconnected systems is a challenging problem in which it is crucial to exploit the available knowledge about the interconnection structure. For time-varying systems, the identification problem is much more difficult. To cope with this issue, this paper addresses the identification of DT dynamical models, composed by the interconnection of time-varying systems.

The purpose of this paper is to present an on-orbit frequency identification method for spacecraft directly using attitude maneuver data. Natural frequency of flexible solar arrays plays an important role in attitude control design of spacecraft with solar arrays, and its precision will directly affect the accuracy of attitude maneuver. However, when the flexibility of the solar arrays is large, because of air damping, gravity effect etc., the frequency obtained by ground test shows great error compared with the on-orbit real value. One solution to this problem is to conduct on-orbit identification during which proper identification methods are used to obtain the parameters of interest based on the real on-orbit data of spacecraft.

The observer/Kalman filter identification and eigensystem realization algorithm are used as identification methods, and the attitude maneuver controller is designed using the rigid-body dynamics method.

Two conclusions are drawn in this paper according to results of numerical simulations. The first one is that the attitude controller based on the rigid-body dynamics method is effective in attitude maneuver of the spacecraft. The second one is that the on-orbit parameter identification can be directly achieved by using attitude maneuver data of spacecraft without adding additional missions.

Based on the methods proposed in this paper, it is convenient to obtain the natural frequencies of the spacecraft using the data of the attitude maneuver, which may greatly reduce the cost of on-orbit identification test.

The way of obtaining natural frequencies based on attitude maneuver data of spacecraft provides high originality and value for practical application.

When a manipulator captures an unknown space object, inertia parameters of endpoint payload should be timely obtained to handle possible unexpected parameter variations and monitor the system’s operating conditions. Therefore, this study aims to present an identification method for estimating the inertia parameter of the payload carried by a flexible two-link space manipulator.

The original nonlinear dynamics model of the manipulator is linearized at a selected working point. Subsequently, the system modal frequencies with and without payload are determined using the subspace identification algorithm, and the difference of these frequencies is computed. Furthermore, by adjusting the structural configuration of the manipulator, multiple sets of frequency differences are obtained. Therefore, the inertia parameters of the payload, i.e. the mass and the moment of inertia, can be derived from the frequency differences by solving a least-squares problem.

The proposed method can effectively estimate the payload parameters and has satisfactory identification accuracy.

The approach’s implementation provides a practical reference for determining inertia parameters of an unknown space target in the capture process.

The study proposes a novel method for identifying the inertia parameters of the payload of a flexible two-link space manipulator using the estimated system frequencies.

The purpose of this paper is to develop identification system for fiber optic connectors in passive distribution cabinets. The system should have alternative power supply and wireless communication unlike the identification systems commercially available, which will make the system fully autonomous.

Detailed project and realization of real demonstrator of fully autonomous identification system. After the realization of the demonstrator, its optimization was performed.

It is possible to build fully autonomous identification system which requires 15.6 mJ energy to perform one cycle of identification process. Moreover, it is possible to use the alternative power method to supply this system.

Fully autonomous identification system of fiber optic connectors with alternative power supply and wireless communication.

The purpose of this paper is to unpack some of the socio‐technical relationships inherent in contemporary notions of personal identity management. For this purpose it considers the issue of personal identity management in terms of a framework, which distinguishes between the related processes of authentication, identification and enrolment.

The conceptual model described in this paper is reflected against an important recent case in which issues of personal identity management are being enacted: the introduction of a UK national identity card. Both this issue and case are particularly examined in the light of the growth of e‐Government in the UK.

The paper relates issues associated with the technical infrastructure of e‐Government with some of the costs and benefits associated with the social infrastructure of e‐Government. This device offers a useful framing for a whole range of issues surrounding individual‐organisation interaction in the Information Society that rely on elements of personal identity management.

In the paper the issue of personal identity management is under‐represented in the Information Systems and Information Management literature. The conceptual approach adopted in the paper is used to identify areas of further research in terms of issues relevant to the technical infrastructure of e‐Government.

The paper identifies a number of personal identity management issues embedded in the technical infrastructure required for effective e‐Government.

This paper raises the importance of personal identity management to the success of the e‐Government agenda. It also links classic information management issues to the issue of personal identity management and identifies the challenges for e‐Government within this.