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961.
Shortest path problem with uncertain arc lengths 总被引:2,自引:0,他引:2
Yuan Gao 《Computers & Mathematics with Applications》2011,62(6):2591-2600
Uncertainty theory provides a new tool to deal with the shortest path problem with nondeterministic arc lengths. With help from the operational law of uncertainty theory, this paper gives the uncertainty distribution of the shortest path length. Also, it investigates solutions to the α-shortest path and the most shortest path in an uncertain network. It points out that there exists an equivalence relation between the α-shortest path in an uncertain network and the shortest path in a corresponding deterministic network, which leads to an effective algorithm to find the α-shortest path and the most shortest path. Roughly speaking, this algorithm can be broken down into two parts: constructing a deterministic network and then invoking the Dijkstra algorithm. 相似文献
962.
V. Coscia 《Computers & Mathematics with Applications》2011,62(10):3902-3911
This paper aims at showing how the so-called mathematical kinetic theory for active particles can be properly developed to propose a new system biology approach. The investigation begins with an analysis of complexity in biological systems, continues with reviewing a general methodology to reduce complexity and furnishes the mathematical tools to describe the time evolution of such systems by capturing all their features. 相似文献
963.
M. RahaeifardM.H. Kahrobaiyan M. AsghariM.T. Ahmadian 《Sensors and actuators. A, Physical》2011,171(2):370-374
This paper investigates the deflection and static pull-in voltage of microcantilevers based on the modified couple stress theory, a non-classic continuum theory capable to predict the size effects for structures in micron and sub-micron scales. It is shown that the couple stress theory can remove the gap between the experimental observations and the classical theory based simulations for the static pull-in voltage. 相似文献
964.
A.-C. SalaünAuthor Vitae F. Le BihanAuthor VitaeT. Mohammed-BrahimAuthor Vitae 《Sensors and actuators. B, Chemical》2011,158(1):138-143
High sensitivity to chemical species of sub-micron gap Suspended-Gate FETs (more than 200 mV/pH for example) is explained from the charge distribution induced by the high field in the sub-micronic gap under the gate-bridge. Modeling of Metal-Electrolyte-Insulator-Silicon (MEIS) capacitor, which is the basic vertical structure of the transistor, is performed to highlight this effect through the response to the pH change of the solution filling the gap. The analytical model is based on the 2D-numerical resolution of Poisson's equation. The response of quasi-static C(V) plots versus pH is simulated using both electrolyte charge distribution and site-binding theory considering the influence of sites densities on silicon nitride. Device modeling and simulated/experimental electrical characteristics are presented. Effect of the gap thickness on the pH sensitivity is also discussed in this study. 相似文献
965.
Kyung Min ByunAuthor VitaeNak-Hyeon KimAuthor Vitae Yeong Hwan KoAuthor VitaeJae Su YuAuthor Vitae 《Sensors and actuators. B, Chemical》2011,155(1):375-379
We demonstrated an enhanced surface plasmon resonance detection incorporating ZnO nanorod arrays (NRAs) built on a thin gold film. ZnO NRAs were fabricated by wet chemical growth method and used for the detection of DNA hybridization. Experimental results exhibited that ZnO NRAs provided a notable sensitivity improvement by more than 3 times, which is attributed to an increase in the surface reaction area. The measured sensitivity enhancement matched well with the numerical analyses based on the effective medium theory. Our approach is intended to show the feasibility and extend the applicability of the ZnO-based SPR biosensor to diverse biomolecular binding events. 相似文献
966.
Context
Although reliability is a major concern of most open source projects, research on this problem has attracted attention only recently. In addition, the optimal version-dating for open source software considering its special properties is not yet discussed.Objective
In this paper, the reliability analysis and optimal version-updating for open source software are studied.Method
A modified non-homogeneous Poisson process model is developed for open source software reliability modeling and analysis. Based on this model, optimal version-updating for open source software is investigated as well. In the decision process, the rapid release strategy and the level of reliability are the two most important factors. However, they are essentially contradicting with each other. In order to consider these two conflicting factors simultaneously, a new decision model based on multi-attribute utility theory is proposed.Results
Our models are tested on the real world data sets from two famous open source projects: Apache and GNOME. It is found that traditional software reliability models provide overestimations of the reliability of open source software. In addition, the proposed decision model can help management to make a rational decision on the optimal version-updating for open source software.Conclusion
Empirical results reveal that the proposed model for open source software reliability can describe the failure process more accurately. Furthermore, it can be seen that the proposed decision model can assist management to appropriately determine the optimal version-update time for open source software. 相似文献967.
为了能够在认知无线电网络中有效、准确地检测出授权用户,提出了基于改进的证据理论的合作频谱感知方案设计方法.根据各个次用户对授权用户进行多次本地检测得出的时域DS融合结果,设计并改进融合顺序和融合结构,将多个时域DS融合结果送到融合中心进行空域DS融合,得到最终判决.在此基础上,给出了融合顺序、融合结构的改变对算法性能的... 相似文献
968.
提出一种新的基于证据理论的数据融合的双效水印算法.首先应用水印公式构造特殊的水印嵌入后条件,根据嵌入系数之间的定性分析提取鲁棒水印;利用嵌入系数之间的定量分析能提取脆弱水印,并能准确定位篡改的区域.其次在嵌入过程中还使用纠错码对水印信息进行调和,把水印重复嵌入到图像信息的不同位置,以便利用纠错码的辅助信息来估计出提取的... 相似文献
969.
针对无线传感器网络的任务如何在最短时间内完成且充分利用网络资源的问题,提出了一种基于可分负载理论的无线传感器网络任务调度算法(WDTA).该算法根据网络中各个节点的处理能力和节点间的通信能力,将总任务从SINK节点下发至网络中.通过去除节点间的通信干扰来提高资源利用率和减少总任务完成时间.算法在两种分群结构的异构网络环境下进行了分析,得到了在各个节点上最合理的任务分配方案,以及最短的任务完成所需时间.理论分析了基于可分负载理论的无线传感器网络任务调度的极限情况.实验结果表明WDTA算法能够通过合理分配任务,而减少任务完成时间及节点能耗.该方案可以作为设计大规模无线传感器网络的原则. 相似文献
970.
The refined process structure tree 总被引:2,自引:0,他引:2