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排序方式: 共有2645条查询结果,搜索用时 5 毫秒
1.
面向业务问题求解的知识供应过程模型 总被引:1,自引:0,他引:1
为了满足企业在业务问题求解方面的实际需求,提出了一个面向业务问题求解的知识供应过程模型。该模型提出了知识供应过程中的问题空间、知识空间和流程空间的概念及其关联关系,并进一步给出了包含知识的获取、评价、存储和重用的知识供应过程的有关算法。该模型与算法将业务问题求解过程与知识供应过程进行了融合,通过关联关系实现了知识的主动供应,在优化了业务问题求解过程的同时,提高了知识积累的质量和知识重用的效率。基于该模型建立了知识管理问题求解的原型系统KMPSS,并得到了初步应用验证。 相似文献
2.
3.
In this paper, we study an E0-like combiner with memory as the keystream generator. First, we formulate a systematic and simple
method to compute correlations of the FSM output sequences (up to certain bits). An upper bound of the correlations is given,
which is useful to the designer. Second, we show how to build either a uni-bias-based or multi-bias-based distinguisher to
distinguish the keystream produced by the combiner from a truly random sequence, once correlations are found. The data complexity
of both distinguishers is carefully analyzed for performance comparison. We show that the multi-bias-based distinguisher outperforms
the uni-bias-based distinguisher only when the patterns of the largest biases are linearly dependent. The keystream distinguisher
is then upgraded for use in the key-recovery attack. The latter actually reduces to the well-known Maximum Likelihood Decoding
(MLD) problem given the keystream long enough. We devise an algorithm based on Fast Walsh Transform (FWT) to solve the MLD
problem for any linear code with dimension L and length n within time O(n+L⋅2
L
). Meanwhile, we summarize a design criterion for our E0-like combiner with memory to resist the proposed attacks. 相似文献
4.
A statistical approach to cryptanalysis of a memoryless function of clock-controlled shift registers is introduced. In the case of zero-order correlation immunity, an algorithm for a shift register initial state reconstruction based on the sequence comparison concept is proposed. A constrained Levenshtein distance relevant for the cryptanalysis is defined and a novel recursive procedure for its efficient computation is derived. Preliminary experimental results are given and open theoretic problems are discussed.Following [11], a Boolean function f(x
1,..., x
n) is said to be mth-order correlation immune if m is the maximum integer such that the random variable f(X
1,..., X
n) is statistically independent of every set of m random variables chosen from the balanced and independent binary random variables X
1,..., X
n. 相似文献
5.
Distributed compressed video sensing (DCVS) is a framework that integrates both compressed sensing and distributed video coding characteristics to achieve a low-complexity video coding. However, how to design an efficient joint reconstruction by leveraging more realistic signal models is still an open challenge. In this paper, we present a novel optimal-correlation-based reconstruction method for compressively sampled videos from multiple measurement vectors. In our method, the sparsity is mainly exploited through inter-signal correlations rather than the traditional frequency transform, wherein the optimization is not only over the signal space to satisfy data consistency but also over all possible linear correlation models to achieve minimum-l1-norm correlation noise. Additionally, a two-phase Bregman iterative based algorithm is outlined for solving the optimization problem. Simulation results show that our proposal can achieve an improved reconstruction performance in comparison to the conventional approaches, and especially, offer a 0.7–9.9 dB gain in the average PSNR for DCVS. 相似文献
6.
在嵌入式系统小型化和高速化的要求趋势下,实时图像处理系统中用通用DSP或专用集成电路来实现算法的计算和控制有一定的不足。文章讨论了一个以通用DSP和FPGA构成的实时图像处理系统的设计方法,最后对某一具体实时图象处理系统设计方案做了阐述。 相似文献
7.
The Transmit BeamForming (TBF) technology, applied in a multiple-transmit radar system, is studied in this paper, where multiple elements of antenna array transmit binary Zero Correlation Zones Orthogonal Signals (ZCZ-OS) independently. For each Direction Of Arrival (DOA) with respect to the transmitting array, the analysis on the gain and sidelobe level of TBF output is presented. This paper focuses on the range sidelobes performance within the main beam (in angle domain). For the normal direction, due to the inherent phase property of ZCZ-OS, the TBF output has part zero sidelobes area, of which the distribution is discussed. For the other directions, a systematic search algorithm to optimize the transmission order of signals is proposed for an optimal relationship chart of DOA and transmission order. The range sidelobe performance within the main beam can be improved as the optimal transmission order is adopted. 相似文献
8.
This study is about control of oxide removal amounts on the shallow trench isolation (STI) patterned wafers using removal rate and thickness of blanket (non-patterned) wafers. At first, the removal properties of plasma enhanced tetra-ethyl ortho-silicate (PETEOS) blanket wafers was investigated, and then it was compared with the removal properties and the planarization (step height) as a function of polishing time of the specific STI patterned wafers. We found that there is a relationship between the amount of oxide removal by blanket and patterned wafers. We analyzed this relationship, and the post-CMP thickness of patterned wafers could be controlled by removal rate and removal target thickness of blanket wafers. As the result of correlation analysis, we confirmed that there was the strong correlation between patterned and blanket wafers (correlation factor: 0.7109). So, we could confirm the repeatability as applying to STI CMP process from the linear formula obtained. 相似文献
9.
Koichi Fujiwara Manabu Kano Shinji Hasebe 《Chemometrics and Intelligent Laboratory Systems》2010,101(2):130-274
The individuality of production devices should be taken into account when soft-sensors are designed for parallelized devices. Since it is expressed as differences of the correlation among measured variables, it is useful to cluster samples on the basis of the correlation among variables for adopting a multi-model approach. In addition, changes in process characteristics can be coped with in the same way. In the present work, a new clustering method, referred to as NC-spectral clustering, is proposed by integrating the nearest correlation (NC) method and spectral clustering. Spectral clustering is a graph partitioning method that can be used for sample classification when an affinity matrix of a weighted graph is given. The NC method can detect samples that are similar to the query from the viewpoint of the correlation without a teacher signal. In the proposed method, the NC method is used for constructing the weighted graph that expresses the correlation-based similarities between samples and the constructed graph is partitioned by using spectral clustering. In addition, a new soft-sensor design method is proposed on the basis of the proposed NC-spectral clustering. The usefulness of the proposed methods is demonstrated through a numerical example and a case study of parallelized batch processes. The performance of the proposed correlation-based method is better than that of the conventional distance-based methods. 相似文献
10.
Physicochemical Properties and Eating Qualities of Milled Rice from Different Korean Elite Rice Varieties 总被引:1,自引:0,他引:1
Mi-Young Kang Catherine W. Rico Chae-Eun Kim 《International Journal of Food Properties》2013,16(3):640-653
Physicochemical properties and palatability of rice from six elite varieties in Korea (Chucheongbyeo, Saechucheongbyeo, Mihyangbyeo, Hitomebore, Nampyeongbyeo, and Ilpumbyeo) were analyzed. All samples, which contained 17–18 g/100 g rice starch amylose, belong to low-amylose rice group. Hitomebore variety showed abundant amount of essential amino acids, highest palatability score (82.9), and lowest mineral content. The rice samples contained relatively similar concentrations of saturated (21–24 g/100 g rice) and unsaturated (75–78 g/100 g rice) fatty acids. Mihyangbyeo variety exhibited the highest amount of protein (8.10 g/100 g rice), sugar content, and pasting temperature (82.75°C) and time (3.78 min), but lowest viscosity values. Ribose, rhamnose, and potassium were found to have negative correlations with palatability and breakdown viscosity, indicating that gelatinization characteristics could also be used in evaluating the eating quality of rice. Results of this study could assist plant breeders in developing rice varieties with improved genetic traits and high eating quality. 相似文献