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排序方式: 共有1341条查询结果,搜索用时 109 毫秒
81.
朱静 《数字社区&智能家居》2006,(12):190-191,206
本文介绍了在PC机平台上设计实现GPS应用程序的方法。重点讨论了PC机与GPS接收机通讯程序设计,以及对GPS信息的提取与分离处理的实现。文中给出了PC机与GPS接收器的硬件连接图以及关键实现程序。 相似文献
82.
Gerd Kunert 《Computing》2002,69(3):265-272
This paper considers a singularly perturbed reaction diffusion problem. It is investigated whether adaptive approaches are
successful to design robust solution procedures. A key ingredient is the a posteriori error estimator. Since robust and mathematically analysed error estimation is possible in the energy norm, the focus is on this choice of norm and its implications. The numerical performance for several model problems confirms
that the proposed adaptive algorithm (in conjunction with an energy norm error estimator) produces optimal results. Hence
the energy norm is suitable for the purpose considered here. The investigations also provide valuable justification for forthcoming
research.
Received October 25, 2001; revised July 12, 2002 Published online: October 24, 2002 相似文献
83.
We present C2 quasi-interpolating schemes with tension properties. The B-splines like functions used in the quasi-interpolanting schemes are parametric cubic curves and their shape can be easily controlled via tension parameters which have an immediate geometric interpretation. Applications to the problem of approximation of curves with shape-constraints are discussed. 相似文献
84.
In this paper Hopfield neural networks with continuously distributed delays are considered. Without assuming the global Lipschitz conditions of activation functions, sufficient conditions for the existence and exponential stability of the almost periodic solutions are established by using the fixed point theorem and differential inequality techniques. The results of this paper are new and they complement previously known results. 相似文献
85.
叙述了新钢公司炼钢厂高性能建筑结构用钢的开发冶炼实践。摸索出转炉低磷钢水冶炼、LF炉钢水精炼及4号连铸机浇注等工艺方法。 相似文献
86.
Lee A. Gladwin 《Cryptologia》2013,37(3):199-211
Abstract The discovery of intercepts in the Japanese “Orange Translations” regarding the sinking of merchant ships (marus) bearing allied POWs led to the conclusion that the Joint Intelligence Center Pacific Ocean Area (JICPOA) gave latitudes and longitudes of these vessels to the Commander, Submarine Force, Pacific (ComSubPac) knowing that POWs would be killed. An examination of the “Orange Translations” reveals that most of the intercepts are from the Japanese Water Transport Code (2468) system, not the “Maru Code” (JN-11). The author concludes that while JICPOA provided ComSubPac with convoy coordinates, they were unaware of the presence of POWs on the marus. 相似文献
87.
Frederick D. Parker 《Cryptologia》2013,37(4):295-313
In 1941, the United States Navy intercepted enough Japanese naval messages to predict the attack on Pearl Harbor if the code which protected them had been solved. The messages would have disclosed that, while the Japanese government cynically conducted diplomatic negotiations with the United States, the Japanese Combined Fleet under Admiral Isoroku Yamamoto, beginning as early as September 1941, systematically prepared ships, crews, weapons, tactics, and a complicated fuel supply system for the most ambitious operation ever undertaken by the Japanese navy. Details of Japan's intentions were hidden from Navy cryptanalysts because of limited manpower resources and because all Japanese navy codes were assigned a lower priority than Japanese diplomatic codes and German submarine threat. 相似文献
88.
David Kahn 《Cryptologia》2013,37(4):273-294
American codebreakers achieved remarkable success in solving Japanese codes, but could not prevent the surprise attack on Pearl Harbor because the Japanese never transmitted anything about the attack on the airwaves. 相似文献
89.
Gene clusters are becoming promising tools for gene identification. The study reveals the purposive genomic distribution of genes toward higher inheritance rates of intact metabolic pathways/phenotypes and, thereby, higher fitness. The co-localization of co-expressed, co-interacting, and functionally related genes was found as genome-wide trends in humans, mouse, golden eagle, rice fish, Drosophila, peanut, and Arabidopsis. As anticipated, the analyses verified the co-segregation of co-localized events. A negative correlation was notable between the likelihood of co-localization events and the inter-loci distances. The evolution of genomic blocks was also found convergent and uniform along the chromosomal arms. Calling a genomic block responsible for adjacent metabolic reactions is therefore recommended for identification of candidate genes and interpretation of cellular functions. As a case story, a function in the metabolism of energy and secondary metabolites was proposed for Slc25A44, based on its genomic local information. Slc25A44 was further characterized as an essential housekeeping gene which has been under evolutionary purifying pressure and belongs to the phylogenetic ETC-clade of SLC25s. Pathway enrichment mapped the Slc25A44s to the energy metabolism. The expression of peanut and human Slc25A44s in oocytes and Saccharomyces cerevisiae strains confirmed the transport of common precursors for secondary metabolites and ubiquinone. These results suggest that SLC25A44 is a mitochondrion-ER-nucleus zone transporter with biotechnological applications. Finally, a conserved three-amino acid signature on the cytosolic face of transport cavity was found important for rational engineering of SLC25s. 相似文献
90.
Abstract. This article investigates home attributes that attract residential burglars in choosing a target. These attributes are the location of the home, its physical appearance, demographic characteristics of the residents, and the security precautions present. The theoretical foundation of the empirical model is the criminal utility maximization behavior that considers costs and benefits as formulated by Becker. However, this article introduces to the model the spatial dimension of the burglar's search for a target. The incidence of burglary is the dependent variable and is measured in a dichotomy scale. The empirical analysis utilizes a survey database of burgled and non-burgled homes that was conducted by the researchers. A logit model is used for the investigation, and the effects of the explanatory variables are calculated as probabilities. The database is unique in the wealth of attributes of individual homes that are relevant to burglars'decision process. 相似文献