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71.
The paper is devoted to developing methods for control of ecological-economic systems consisting of three hierarchically subordinate subjects of control. In describing the dynamics of a system state, equations in partial derivatives that are solved numerically according to a semi-implicit scheme of the finite-difference method are used. To achieve its main goal (maintenance of an ecological subsystem in stable state), the subject of control of the upper level applies different control methods. Methods of hierarchical control (motivation, enforcement, and persuasion) that differ in the direction of action (on the objective function or domain of admissible controls) are proposed; examples of their use are represented and a comparative analysis of the obtained results is made. 相似文献
72.
We propose a visualization based approach for digital signature authentication. Using our method, the speed and pressure aspects of a digital signature process can be clearly and intuitively conveyed to the user for digital signature authentication. Our design takes into account both the expressiveness and aesthetics of the derived visual patterns. With the visual aid provided by our method, digital signatures can be authenticated with better accuracy than using existing methods—even novices can examine the authenticity of a digital signature in most situations using our method. To validate the effectiveness of our method, we conducted a comprehensive user study which confirms positively the advantages of our approach. Our method can be employed as a new security enhancement measure for a range of business and legal applications in reality which involve digital signature authorization and authentication. 相似文献
73.
74.
Dan Song Ruofeng Tong Jian Chang Xiaosong Yang Min Tang Jian Jun Zhang 《Computer Graphics Forum》2016,35(7):147-156
Estimation of 3D body shapes from dressed‐human photos is an important but challenging problem in virtual fitting. We propose a novel automatic framework to efficiently estimate 3D body shapes under clothes. We construct a database of 3D naked and dressed body pairs, based on which we learn how to predict 3D positions of body landmarks (which further constrain a parametric human body model) automatically according to dressed‐human silhouettes. Critical vertices are selected on 3D registered human bodies as landmarks to represent body shapes, so as to avoid the time‐consuming vertices correspondences finding process for parametric body reconstruction. Our method can estimate 3D body shapes from dressed‐human silhouettes within 4 seconds, while the fastest method reported previously need 1 minute. In addition, our estimation error is within the size tolerance for clothing industry. We dress 6042 naked bodies with 3 sets of common clothes by physically based cloth simulation technique. To the best of our knowledge, We are the first to construct such a database containing 3D naked and dressed body pairs and our database may contribute to the areas of human body shapes estimation and cloth simulation. 相似文献
75.
ATM论坛将基于速率的流量控制选定为ABR业务的流量控制方法。通过对基于速率的流量控制和基于凭证的流量控制方法的研究,提出了一种信元丢弃流量控制原则,该模型继承了基于凭证方法的记数机制,通过设定高低缓存门限和调节速率升降因数来控制源端速率,仿真结果表明,这种控制机制不仅能够保证缓存的充分利用,而且能够提高其在减少信元丢失等方面的性能。 相似文献
76.
77.
Attempts to carry out the hydroformylation of allyldiethylamine homogeneously catalyzed by rhodium complexes led to unexpected formation of N,N,N,N-tetraethyl-1,4-diaminobutane and 4-(diethylamino)-1-butanole as final products. The role of the catalyst on the product formation and the reaction mechanism are briefly discussed. 相似文献
78.
Comments on the effect of yttrium on the early stages of oxidation of alumina formers 总被引:3,自引:0,他引:3
Jerzy Jedliński 《Oxidation of Metals》1993,39(1-2):55-60
79.
R. Feng Jon G. Houseman A. E. R. Downe J. T. Arnason 《Journal of chemical ecology》1993,19(9):2047-2054
The biochemical basis for the tolerance of the European corn borer,Ostrinia nubilalis, to the phototoxin-terthienyl was investigated by measuring the midgut polysubstrate monooxygenases and glutathioneS-transferase activities.-Terthienyl administered in the diet to the corn borers increased the level of cytochromeb
5, NADH-cytochromec reductase,O-demethylase, and glutathioneS-transferase activities. The induced detoxification enzyme activities should enable the corn borer to metabolize-terthienyl more efficiently and therefore render the corn borer highly tolerant to-terthienyl. 相似文献
80.
介绍了在实际教学中应用VHDL设计出一种能产生m序列数字信号的发生器.该序列发生器具有序列长度和反馈连接设置,能产生多种m序列波形的特点.在软件上采用Altera公司的MAX+plusⅡ,完成m序列发生器的软件设计及仿真工作.通过北京百科融创科技有限公司的RC-EDA-IV型系统的开发板以及Altera公司的max7000s中的EPM7128SLC84-15芯片进行硬件下载测试,用数字示波器观察生成的m序列波形,实现了主要技术指标中的各项要求. 相似文献