algorithms an developed simultaneously with systolic architectures for multidimensional adaptive filtering. Because of the extremely high data rate required for real-time video processing, even with the use of highly ...
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algorithms an developed simultaneously with systolic architectures for multidimensional adaptive filtering. Because of the extremely high data rate required for real-time video processing, even with the use of highly concurrent algorithms and architectures, there is a strong motivation to limit the size of any adaptation problem. The combination of the McClellan transformation as an efficient parametrization for a multidimensional least-squares;(LS) adaptive filter, coupled with systolic arrays to adapt and Implement the filter, yields a novel solution to the problem of adapting a large zero-phase finite impulse response (FIR) multidimensional filter, having arbitrary directional biases, with only a few parameters. Furthermore, it is shown that these filters can be adapted abruptly on a block-by-block basis without causing blocking effects. After developing a basic processing element for a systolic array realization of the Chebychev structure for the McClellan transformation, It Is shown that for a given 2-D transformation function, the adaptation of the I-D prototype filter becomes a small multichannel adaptation problem similar to adaptive army problems. For real-time video applications, such an adaptation algorithm can be performed efficiently using a systolic array of CORDIC processing elements. A similar approach is also taken in developing algorithms to adapt the 2-D transformation function.
Lithium-ion (Li-ion) batteries are ubiquitous sources of energy for portable electronic devices. Compared to alternative battery technologies, Li-ion batteries provide one of the best energy-to-weight ratios, exhibit ...
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Lithium-ion (Li-ion) batteries are ubiquitous sources of energy for portable electronic devices. Compared to alternative battery technologies, Li-ion batteries provide one of the best energy-to-weight ratios, exhibit no memory effect, and have low self-discharge when not in use. These beneficial properties, as well as decreasing costs, have established Li-ion batteries as a leading candidate for the next generation of automotive and aerospace applications. In the automotive sector, increasing demand for hybrid electric vehicles (HEVs), plug-in HEVs (PHEVs), and EVs has pushed manufacturers to the limits of contemporary automotive battery technology. This limitation is gradually forcing consideration of alternative battery technologies, such as Li-ion batteries, as a replacement for existing leadacid and nickel-metal-hydride batteries. Unfortunately, this replacement is a challenging task since automotive applications demand large amounts of energy and power and must operate safely, reliably, and durably at these scales. The article presents a detailed description and model of a Li-ion battery. It begins the section "Intercalation-Based Batteries" by providing an intuitive explanation of the fundamentals behind storing energy in a Li-ion battery. In the sections "Modeling Approach" and "Li-Ion Battery Model," it present equations that describe a Li-ion cell's dynamic behavior. This modeling is based on using electrochemical principles to develop a physics-based model in contrast to equivalent circuit models. A goal of this article is to present the electrochemical model from a controls perspective.
作者：
Koubková, AKoubek, VCharles Univ
Fac Math & Phys Dept Software Engn Prague 11800 1 Czech Republic Charles Univ
Fac Math & Phys Dept Theoret Comp Sci & Math Log Prague 11800 1 Czech Republic Charles Univ
Fac Math & Phys Inst Theoret Comp Sci Prague 11800 1 Czech Republic
Let sigma'(n) denote the number of all strongly connected graphs on the n-element set. We prove that sigma'(n) greater than or equal to 2(n2) (1- n(n - 1)/2(n-1)). Hence the algorithm computing a transitive cl...
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Let sigma'(n) denote the number of all strongly connected graphs on the n-element set. We prove that sigma'(n) greater than or equal to 2(n2) (1- n(n - 1)/2(n-1)). Hence the algorithm computing a transitive closure by a reduction to acyclic graphs has the expected time O(n(2)), under the assumption of uniform distribution of input graphs. Furthermore, we present a new algorithm constructing the transitive closure of an acyclic graph. (C) 2002 Elsevier Science B.V. All rights reserved.
Numerical methods are outlined for computing the velocity potential, and its derivatives, for linearized three-dimensional wave motions due to a unit source with harmonic time dependence beneath a free surface. Two di...
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Numerical methods are outlined for computing the velocity potential, and its derivatives, for linearized three-dimensional wave motions due to a unit source with harmonic time dependence beneath a free surface. Two distinct cases are considered where the fluid depth is either infinite, or of constant finite depth. Efficient algorithms are developed in both cases, to replace the numerical evaluation of the relevant integrals by multi-dimensional approximations in economized polynomials. This technique is substantially faster than conventional direct methods based on numerical integration.
algorithms for calculating an aircraft's orientation angles based on the results of the numerical integration of Poisson's and quaternion equations are proposed. The algorithms in the presence of random errors...
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algorithms for calculating an aircraft's orientation angles based on the results of the numerical integration of Poisson's and quaternion equations are proposed. The algorithms in the presence of random errors of the matrix elements of direction cosines and quaternions are characterized by a significantly higher accuracy in comparison to the formulas for solving the formulated problem. The results of testing the mathematical modeling data under random errors, which confirm the increased accuracy of the calculation of the orientation angles, are given.
Whereas earlier work on spatiotemporal databases generally focused on geometries changing in discrete steps, the emerging area of moving objects databases supports geometries changing continuously. Two important abstr...
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Whereas earlier work on spatiotemporal databases generally focused on geometries changing in discrete steps, the emerging area of moving objects databases supports geometries changing continuously. Two important abstractions are moving point and moving region, modelling objects for which only the time-dependent position, or also the shape and extent are relevant, respectively. Examples of the first kind of moving entity are all kinds of vehicles, aircraft, people or animals;of the latter hurricanes, forest fires, forest growth or oil spills in the sea. The goal is to develop data models and query languages as well as DBMS implementations supporting such entities, enabling new kinds of database applications. In earlier work we have proposed an approach based on abstract data types. Hence, moving point or moving region are viewed as data types with suitable operations. For example, a moving point might be projected into the plane, yielding a curve, or a moving region be mapped to a function describing the development of its size, yielding a real-valued function. A careful design of a system of types and operations (an algebra) has been presented, emphasizing completeness, closure, consistency and genericity. This design was given at an abstract level, defining, for example, geometries in terms of infinite point sets. In the next step, a discrete model was presented, offering finite representations and data structures for all the types of the abstract model. The present paper provides the final step towards implementation by studying and developing systematically algorithms for (a large subset of) the operations. Some of them are relatively straightforward;others are quite complex. algorithms are meant to be used in a database context;we also address filtering techniques and practical issues such as large object management or numeric robustness in the context of an ongoing prototype implementation.
This paper investigates pre-images (ancestors or past configurations) of specified configurations of one-dimensional cellular automata. Both counting and listing of pre-images are discussed. The main graphical tools u...
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This paper investigates pre-images (ancestors or past configurations) of specified configurations of one-dimensional cellular automata. Both counting and listing of pre-images are discussed. The main graphical tools used are the de Bruijn diagram, and its extension the pre-image network, which is created by concatenating de Bruijn diagrams. The counting of pre-images is performed as the multiplication of topological matrices of de Bruijn diagrams. Listing of pre-images is described using two algorithms. The first algorithm traces paths in the pre-image network and focuses on local knowledge of the network. The second performs a complete analysis of the network before proceeding with listing. (c) 2007 Elsevier B.V. All rights reserved.
Problems of development and analysis of construction high-detailed digital models of an object surface are addressed. It is also supposed that simulated objects are not standard;i.e., they are bounded by a surface of ...
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Problems of development and analysis of construction high-detailed digital models of an object surface are addressed. It is also supposed that simulated objects are not standard;i.e., they are bounded by a surface of a complex form, and their digital representation require generating a very large number of points. Special attention is paid to problems of constructing a hierarchical structure of algorithms, including the analysis of various strategies of condensing points and surface approximation. For a number of examples, the capabilities of the developed technique are demonstrated for various objects and different types of imagery. DOI: 10.1134/S1064230711040046
algorithms play an increasing role in food retailing and distribution. Through a longitudinal study supported by qualitative interviews, we explore how such technologies have turned the sourcing of food into a highly ...
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algorithms play an increasing role in food retailing and distribution. Through a longitudinal study supported by qualitative interviews, we explore how such technologies have turned the sourcing of food into a highly automated transaction, moving from explore and exploit to embed and embalm. We demonstrate the impact that embedding algorithms can have on organizational processes and structures and that this may shift the balance of power within the value chain without being visible to management.
The specification of a graphical user interface (GUI), like any other part of a computer system, is an incremental process whereby an outline of the system is systematically developed, evaluated, and revised until it ...
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The specification of a graphical user interface (GUI), like any other part of a computer system, is an incremental process whereby an outline of the system is systematically developed, evaluated, and revised until it is reasonably complete. This article describes some algorithms and procedures that can be used to automate the analysis of a specification to facilitate this iterative process. A propositional production system (PPS) is a notation that can be used by designers to describe the high-level behavior of a GUI. Such a description is executable and relatively easy to learn and use. PPSs are a form of state machine;therefore, much of the theory of state machines can be applied to their analysis. PPSs, however, provide the advantage of semiparallel definitions of state transitions. This is important, as dialogue models of modern GUIs allow a large number of simultaneously available inputs leading to very large state spaces. By dealing in sets of states, a PPS makes the problem of describing the potentially exponential number of state transitions tractable. This article discusses how this innovation can lead to efficient algorithms for analyzing a dialogue model for properties such as task completeness, reversibility of effect, accessibility, connectedness, and avoidance of deadlock.
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