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81.
82.
The paper addresses the problem of multi-slot just-in-time scheduling. Unlike the existing literature on this subject, it
studies a more general criterion—the minimization of the schedule makespan rather than the minimization of the number of slots
used by schedule. It gives an O(nlog 2
n)-time optimization algorithm for the single machine problem. For arbitrary number of m>1 identical parallel machines it presents an O(nlog n)-time optimization algorithm for the case when the processing time of each job does not exceed its due date. For the general
case on m>1 machines, it proposes a polynomial time constant factor approximation algorithm. 相似文献
83.
84.
Marcin Miłkowski 《Minds and Machines》2009,19(4):465-475
In Darwin’s Dangerous Idea, Daniel Dennett claims that evolution is algorithmic. On Dennett’s analysis, evolutionary processes are trivially algorithmic
because he assumes that all natural processes are algorithmic. I will argue that there are more robust ways to understand
algorithmic processes that make the claim that evolution is algorithmic empirical and not conceptual. While laws of nature
can be seen as compression algorithms of information about the world, it does not follow logically that they are implemented
as algorithms by physical processes. For that to be true, the processes have to be part of computational systems. The basic
difference between mere simulation and real computing is having proper causal structure. I will show what kind of requirements
this poses for natural evolutionary processes if they are to be computational. 相似文献
85.
Tomasz Fałat Kazimierz Friedel Norman Marenco Stephan Warnat 《Microsystem Technologies》2009,15(1):181-190
The current paper focuses on several mechanical aspects of a waferlevel packaging approach using a direct face-to-face Chip-to-Wafer
(C2W) bonding of a MEMS device on an ASIC substrate wafer. Requirements of minimized inherent stress from packaging and good
decoupling from forces applied in manufacturing and application are discussed with particular attention to the presence of
through-silicon vias (TSV) in the substrate wafer. The paper deals with FEM analysis of temperature excursion, pressure during
molding, materials used and handling load influence on mechanical stress within the TSV system and on wafer level, which can
be large enough to disintegrate the system. 相似文献
86.
87.
In this paper a novel Tensor-Based Image Segmentation Algorithm (TBISA) is presented, which is dedicated for segmentation of colour images. A purpose of TBISA is to distinguish specific objects based on their characteristics, i.e. shape, colour, texture, or a mixture of these features. All of those information are available in colour channel data. Nonetheless, performing image analysis on the pixel level using RGB values, does not allow to access information on texture which is hidden in relation between neighbouring pixels. Therefore, to take full advantage of all available information, we propose to incorporate the Structural Tensors as a feature extraction method. It forms enriched feature set which, apart from colour and intensity, conveys also information of texture. This set is next processed by different classification algorithms for image segmentation. Quality of TBISA is evaluated in a series of experiments carried on benchmark images. Obtained results prove that the proposed method allows accurate and fast image segmentation. 相似文献
88.
We investigate families of finite initial segments of standard models for various arithmetics. We give an axiomatization of the theory of sentences true in almost all finite models with addition. We also characterize its complete extensions and relate its infinite models to models of Presburger arithmetic.We also estimate the complexity of complete extensions of the arithmetic with addition and multiplication. 相似文献
89.
We propose an efficient algorithm for computing a unit lower triangular n×n matrix with prescribed singular values of O(n
2) cost. This is a solution of the question raised by N. J. Higham in [4, Problem 26.3, p. 528].
Received July 21, 1999; revised November 4, 1999 相似文献
90.
Bolesław Kacewicz 《Mathematics of Control, Signals, and Systems (MCSS)》2000,13(4):347-359
In contrast to the worst case approach, the average case setting provides less conservative insight into the quality of estimation
algorithms. In this paper we consider two local average case error measures of algorithms based on noisy information, in Hilbert
norms in the problem element and information spaces. We define the optimal algorithm and provide formulas for its two local
errors, which explicitly exhibit the influence of factors such as information, information (measurement) errors, norms in
the considered spaces, a subset where approximations are allowed, and “unmodeled dynamics.” Based on the error expression,
we formulate in algebraic language the problem of selecting the optimal approximating subspace. The solution is given along
with the specific formula for the error, which depends on the eigenvalues of a certain matrix defined by information and norms
under consideration.
Date received: November 25, 1999. Date revised: May 30, 2000. 相似文献