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51.
The honeycomb rectangular torus is an attractive alternative to existing networks such as mesh-connected networks in parallel and distributed applications because of its low network cost and well-structured connectivity. Assume that m and n are positive even integers with n ? 4. It is known that every honeycomb rectangular torus HReT(m,n) is a 3-regular bipartite graph. We prove that in any HReT(m,n), there exist three internally-disjoint spanning paths joining x and y whenever x and y belong to different partite sets. Moreover, for any pair of vertices x and y in the same partite set, there exists a vertex z in the partite set not containing x and y, such that there exist three internally-disjoint spanning paths of G-{z} joining x and y. Furthermore, for any three vertices x, y, and z of the same partite set there exist three internally-disjoint spanning paths of G-{z} joining x and y if and only if n ? 6 or m = 2.  相似文献   
52.
基于IPv6校园网的智能选课系统的J2EE架构的设计与实现   总被引:2,自引:0,他引:2  
刘敏  滕华  董文  谯石 《数据通信》2006,(3):56-58
通过分析IPv6校园网自主学习模式下的自主选课问题,提出了利用J2EE技术构建基于IPv6校园网的智能选课系统的总体结构及具体实现.  相似文献   
53.
徐腾 《中国人造板》2006,13(8):23-23,28
厚单板染色加工难以获得良好的透染性、均染性和较高的色牢度。采用高温高压工艺和分散性、渗透性较好的染料浸染厚单板,可以获得良好的染色效果。  相似文献   
54.
By using Cokelet's wave theory,the limiting wave height and the relative waveangular frequency in wave-current field were calculated in this paper.It is indicated by numeri-cal calculation that if the water depth is not too small,the result given by authors'calculationare very close to the results of limiting wave height by Dalrymple(1975)and to the data of rel-ative wave angular frequency by linear wave theory;but if water depth is rather small,thereare some discrepancy,  相似文献   
55.
While many scholars of organizational innovations have examined characteristics of innovations such as relative advantage and complexity and how they facilitate the adoption of an innovation by organizations, others have used mathematical models to fit diffusion patterns. In this study, the authors attempt to integrate these two areas of inquiry and explore the possibilities to predict diffusion patterns based on characteristics of the innovation and the adopting entities. Based on a cross-sectional sample of 313 large American firms, 20 information technology (IT) innovations were examined and their diffusion patterns assessed with respect to models that espoused internal and external influence. The mixed influence model (Bass model) was chosen as a robust common representation for the set of diffusion patterns. However, the external influence as represented by the coefficient of innovation was found to be extremely small and the internal influence dominates for all innovations. The other two parameters of the model, the saturation level and the coefficient of imitation, which represents internal influence, were then used to perform a cluster analysis. Five clusters of technologies emerged, and the potential relationships between their innovation characteristics and diffusion patterns were explored. Rigorous examination of these potential relationships by future researchers may result in practical methods for predicting patterns of IT innovation diffusion based on innovation and technology characteristics  相似文献   
56.
MT3 shows apparently different properties and function fromMT1 even though they have 70% sequence homology. Possibly thetwo inserts, Thr5 and a negatively charged hexapeptide at position-55in MT3, play important roles. A series of MT3 variants aroundthe EAAEAE hexapeptide have been prepared by site-directed mutagenesisand their properties and reactivity towards pH, EDTA and DTNBhave been studied. Our detailed studies revealed that the EAAEAEinsert is essential to the property of MT3. It is the hexapeptideinsert, to some extent, making the MT3  相似文献   
57.
The authors describe an experiment, a model, and an analytic method for on/off vs. continuous policy evaluation. The methodology was developed and verified through experimentation. An experimental life-test of small DC motors was designed and performed; it involved on/off cycling vs. continuous operation under multiple stresses. A stress-factor reliability model based on the two-parameter Weibull proportional-hazards life distribution was fitted to the data. The analysis provides an estimate of the model parameters for the life distribution of the DC motors under two operating policies, while under multiple stresses. The characteristic life was related to the explanatory covariates: voltage, on/off cycling, and load. Due to the proportional hazards (common Weibull shape) nature of the model, acceleration factors were calculated to relate the stress levels. The reliability model was extended to develop a simple rule to aid in a decision between on/off cycling and continuous-run policies (to achieve higher reliability). The proposed model (with covariates) allows a much broader approach to reliability modeling than the usual Weibull model (without covariates) because it predicts the reliability under various environmental combinations  相似文献   
58.
针对火焰动画难以快速建模和绘制的问题,提出了完全利用GPU过程化生成火焰动画的高效算法。先用建模工具在预处理阶段构建一个由平面正方形组成的三维模型,在绘制阶段通过GPU编程对这些方形进行Billboard方式的变换,并用一些简单公式对他们的运动方式、大小和颜色来用过程化方式进行控制,最后通过alpha混合得到最终结果。算法完全在GPU里实现,能满足实时的绘制要求。  相似文献   
59.
光学遥感舰船目标识别方法   总被引:1,自引:0,他引:1       下载免费PDF全文
提出一种基于粗糙集理论和分层判别回归技术的光学遥感舰船目标识别方法。该方法首先提出新的光学遥感舰船识别特征———面积比编码,并与四类特征组合作为备选特征;然后基于粗糙集理论按同可区分度来计算各备选特征的重要性权值,自动选择出对正确识别贡献较大的特征组合;最后根据分层判别回归原理生成分类判决树来识别光学遥感舰船目标。实验结果表明,本文方法在识别精度和速度方面优于最近邻和支持向量机方法,且通用可行。  相似文献   
60.
方霞  滕云辉 《办公自动化》2012,(16):23-24,38
大学生物品交换系统的宗旨在于不求回报无偿付出,在充分利用各种资源的同时,培养学生的勤俭节约意识和"低碳"意识,加强学生之间的联系与互动,促进节约型校园的发展,并且符合近年来一直倡导的"和谐校园"与"低碳校园"的要求。系统基于B/S结构,采用ASP作为系统开发语言,使用SQL SERVER 2000数据库作为整个交易系统的数据库服务器,提供数据存储和调用,实现基于B/S结构的大学生物品交换系统。  相似文献   
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