The problem of inputs decoupled observer design for linear descriptor systems that was not square with unknown inputs was considered. When the descriptor systems were impulsively controllable, under the nonsingular tr...
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The problem of inputs decoupled observer design for linear descriptor systems that was not square with unknown inputs was considered. When the descriptor systems were impulsively controllable, under the nonsingular transformation, equivalent standard state space systems were derived via regarding the partial state as unknown input. The sufficient conditions for the existence of the observer and simple method to design the observer are given, and the state and unknown inputs of the descriptor systems are asymptotically estimated using the state of observer, control input and output of descriptor systems.
The basic material characteristics of chitosan films composed of chitosan ranging from 76% DDA to 95% DDA were studied. Chitosan powder of known DDA and molecular weight were dissolved in 0.2 M acetic acid and cast. D...
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ISBN:
(纸本)1877040193
The basic material characteristics of chitosan films composed of chitosan ranging from 76% DDA to 95% DDA were studied. Chitosan powder of known DDA and molecular weight were dissolved in 0.2 M acetic acid and cast. Drying occurred over a seven day period with day 1 and 7 in a laminar flow. The results from X ray diffraction data showed that the amorphous concentration decreased with as the DDA increased. It was also observed that the DDA increased seen both NAHDF and UMRs when comparing only the chitosan films.
Let H be a fixed graph on h vertices. We say that a graph G is induced H-free if it does not contain any induced copy of H. Let G be a graph on n vertices and suppose that at least en2 edges have to be added to or rem...
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Let H be a fixed graph on h vertices. We say that a graph G is induced H-free if it does not contain any induced copy of H. Let G be a graph on n vertices and suppose that at least en2 edges have to be added to or removed from it in order to make it induced H-free. It was shown in [5] that in this case G contains at least f(Ε,h)nh induced copies of H, where 1/f(Ε, h) is an extremely fast growing function in 1/Ε, that is independent of n. As a consequence, it follows that for every H, testing induced H-freeness with one-sided error has query complexity independent of n. A natural question, raised by the first author in [1], is to decide for which graphs H the function 1/f(Ε,H) can be bounded from above by a polynomial in 1/Ε. An equivalent question is for which graphs H, can one design a one-sided error property tester for testing induced H-freeness, whose query complexity is polynomial in 1/Ε. We settle this question almost completely by showing that, quite surprisingly, for any graph other than the paths of lengths 1, 2 and 3, the cycle of length 4, and their complements, no such property tester exists. We further show that a similar result also applies to the case of directed graphs, thus answering a question raised by the authors in [9]. We finally show that the same results hold even in the case of two-sided error property testers. The proofs combine combinatorial, graph theoretic and probabilistic arguments with results from additive number theory.
Beginning undergraduate engineering students need computing skills. A course was developed to support the retention of those undergraduates who were lacking in basic computing skills. This paper discusses the results ...
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Beginning undergraduate engineering students need computing skills. A course was developed to support the retention of those undergraduates who were lacking in basic computing skills. This paper discusses the results of using novel technologies in an assimilation course. The technologies consisted of autonomous robots that were relatively easy to build and Pocket PCs with an integrated wireless capability in order to access the Internet. The paper includes the background information on the course, technologies, and the applicability. In addition, student experiences with the tools are also covered in the paper.
Analyze stability of switched systems with linear and time-varying system matrices. First, present two concepts: equal-time interval (ETI) switching sequence and periodic switching sequence. Then under periodic switch...
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ISBN:
(纸本)0780382730
Analyze stability of switched systems with linear and time-varying system matrices. First, present two concepts: equal-time interval (ETI) switching sequence and periodic switching sequence. Then under periodic switching sequences derive sufficient conditions for stability and instability of the systems based on matrix measure theory. Further simplify the conditions for time-invariant ones. Last give two examples to illustrate the effectiveness of the results.
In this paper finite-time control problems for linear singular systems subject to time-varying parametric uncertainties and exogenous disturbances. The main result provided is a sufficient is reduced to a feasibility ...
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In this paper finite-time control problems for linear singular systems subject to time-varying parametric uncertainties and exogenous disturbances. The main result provided is a sufficient is reduced to a feasibility problem involving linear matrix inequalities (LMI) with one restriction condition. The detailed solving method of such LMIs is given finally.
The finite-time control problem for one kind of linear singular systems subject to norm bounded time-varying parametric uncertainties and exogenous disturbances is considered. The main results provided are sufficient ...
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The finite-time control problem for one kind of linear singular systems subject to norm bounded time-varying parametric uncertainties and exogenous disturbances is considered. The main results provided are sufficient conditions for robust finite-time stabilization via state feedback. The conditions are then reduced to feasibility problems involving linear matrix inequalities (LMIs). A detailed example is presented to illustrate the proposed methodology.
Tool support for Information Systems development can be considered from many perspectives, and it is not surprising that different stakeholders perceive such tools very differently. This can contribute on one side to ...
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ISBN:
(纸本)9728865007
Tool support for Information Systems development can be considered from many perspectives, and it is not surprising that different stakeholders perceive such tools very differently. This can contribute on one side to poor selection processes and ineffective deployment of CASE, and on another to inappropriate tool development. In this paper we consider the relationship between CASE tools and Information Systems development methods from three stakeholder perspectives: concept developer, Information Systems developer and product developer. These perspectives, and the tensions between them, are represented within a 'stakeholder triangle', which we use to consider how the concept of method-in-action affects and is affected by the concept of method-in-tool. We believe that the triangle helps when interpreting seemingly conflicting views about CASE adoption and development.
In this paper, the admissible initial value set and dynamic feedback control of nonlinear differential-algebraic systems are considered. An algorithm to calculate the admissible initial value set is given. Based on th...
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In this paper, the admissible initial value set and dynamic feedback control of nonlinear differential-algebraic systems are considered. An algorithm to calculate the admissible initial value set is given. Based on the algorithm, the differential-algebraic system can be transformed to a standard state space system constrained in an invariant set. If the standard state space system constrained in the invariant set can be stabilized, then the original differential-algebraic system can be stabilized by a dynamic feedback controller.
We study a wide range of online graph and network optimization problems, focusing on problems that arise in the study of connectivity and cuts in graphs. In a general online network design problem, we have a communica...
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We study a wide range of online graph and network optimization problems, focusing on problems that arise in the study of connectivity and cuts in graphs. In a general online network design problem, we have a communication network known to the algorithm in advance. What is not known in advance are the bandwidth or cut demands between nodes in the network. Our results include an O(log m log n ) competitive randomized algorithm for the online non-metric facility location and for a generalization of the problem called the multicast problem. In the non-metric facility location m is the number of facilities and n is the number of clients. The competitive ratio is nearly tight. We also present an O (log2 n log k) competitive randomized algorithm for the online group Steiner problem in trees and an O(log3n log k) competitive randomized algorithm for the problem in general graphs, where n is the number of vertices in the graph and k is the number of groups. Finally, we design a deterministic O (log3 n log log n) competitive algorithm for the online multi-cut problem. Our algorithms are based on a unified framework for designing online algorithms for problems involving connectivity and cuts. We first present a general O(log m)-deterministic algorithm for generating fractional solution that satisfies the online connectivity or cut demands, where m is the number of edges in the graph. This may be of independent interest for solving fractional online bandwidth allocation problems, and is applicable to the node version as well. The integral solutions are obtained by an online rounding of the fractional solution. This part of the framework is problem dependent, and applies various tools including results on the approximate max-flow min-cut for multicommodity flow, the HST method and its extensions, certain rounding techniques for dependent variables, and Räcke's new hierarchical decomposition of graphs.
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