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71.
The reverse construction and analysis of the networks of molecular interactions are essential for understanding their functions within cells. In this paper, a logic network model is constructed to investigate the complicated regulation mechanism of shoot genes of Arabidopsis Thaliana in response to stimuli. The dynamics of the complicated logic network is analyzed, discussed, and simulated. The simulation results show that the logic network of the active genes of shoot eventually evolves into eleven attractors under the stimuli, including five 1-periodic and six 2-periodic attractors. Our work provides valuable reference and guidance for biologists to understand and explain Arabidopsis’ response to external stimuli by experiments.  相似文献   
72.
The approach of available transfer capability (denoted as ATC) incorporating wind generation has been paid very high attention since the development of wind generation. Based on the maximum function, this paper presents an ATC model. The characteristic of the new model is twofold. First, it considers wind turbines connected to power system and static security of power system simultaneously. Second, it is a system of semismooth equations and can be solved easily. By using the smoothing strategy, a smoothing Newton method is adopted for solving the proposed new ATC model. Numerical simulation results of the IEEE 30-bus and 118-bus system show that the new model and algorithm are feasible and effective. The impact of wind turbines connected to power system on ATC is also analyzed.  相似文献   
73.
<正> This paper considers finite-time χ-consensus problem for a multi-agent system with firstorderindividual dynamics and switching interaction topologies.Several distributed finite-time consensusrules are constructed for multi-agent dynamics in a unified way with the help of Lyapunovfunction and graph theory as well as homogeneity.Time-invariant non-smooth forms of finite-timeneighbor-based controllers are proposed and a numerical example is shown for illustration.  相似文献   
74.
<正> This paper analyzes performance of optimal channel estimation and multiuser detection(MUD) in a block-fading code-division multiple-access (CDMA) channel on the assumptions of randomspreading and large-system limit,by using the replica method developed in statistical mechanics.The authors find that the asymptotic spectral efficiency of the linear minimum mean-squared error(LMMSE) MUD which was proposed and analyzed by Evans and Tse in 2000 is indistinguishable fromthat of the optimal MUD for small system loads.Our results imply that performance of MUD scarcelyimproves even if one spends more computational cost than that of the LMMSE MUD,i.e.,at most thecube of the number of users,on the above-described conditions.  相似文献   
75.
<正> This paper considers the problem of actuator failure compensation for a class of nonlinearsystems in the form of output-feedback.MT-filters are exploited to estimate the unmeasured states.The backsteppping technique is used to construct the controller recursively.The proposed compensationscheme can grantee the boundedness of all the closed-loop signals and asymptotic output tracking.Thetheoretical results are illustrated by a simulation example.  相似文献   
76.
<正> This paper discusses the null boundary controllability of two PDE's,modeling a compositesolid with different physical properties in each layer.Interface conditions are imposed.  相似文献   
77.
<正> This paper formulates and analyzes a line search method for general nonlinear equalityconstrained optimization based on filter methods for step acceptance and secant methods for searchdirection.The feature of the new algorithm is that the secant algorithm is used to produce a searchdirection,a backtracking line search procedure is used to generate step size,some filtered rules areused to determine step acceptance,second order correction technique is used to reduce infeasibility andovercome the Maratos effect.Global convergence properties of this method are analyzed:under mildassumptions it is showed that every limit point of the sequence of iterates generated by the algorithmis feasible,and that there exists at least one limit point that is a stationary point for the problem.Moreover,it is also established that the Maratos effect can be overcome in our new approach by addingsecond order correction steps so that fast local superlinear convergence to a second order sufficient localsolution is achieved.Finally,the results of numerical experiments are reported to show the effectivenessof the line search filter secant method.  相似文献   
78.
为改变零售业缺货的现状,供应商管理库存(VMI)被广泛应用,同时配送中心的配送与调度效率就成为影响零售商缺货与否的关键。本文在考虑销售损失的基础上,研究了配送中心配送时的调度策略。假设由缺货引起的销售损失与缺货时间平方成正比,首先给出了完全信息下的最优离线策略。然后,引入占线方法,研究各销售点需求序列未知情况下,提出了权衡销售损失最大的优先处理策略,并将其竞争比m+2M/3m与先来先处理、按销售损失最大处理两个传统策略进行了对比。  相似文献   
79.
根据迫零检测(zero forcing,ZF)结合排序干扰消除(ordered successive interference cancellation,OSIC)的接收机结构,并针对功率控制理想和非理想两种场景,分别基于随机配对调度准则和机会主义配对调度(opportunistic)准则分析了VMIMO-AS系统容量的下限和上限.最后的蒙特·卡罗仿真取得和理论分析基本一致的仿真结果,从而进一步验证了理论分析的正确性.  相似文献   
80.
RZWQM模型介绍及其应用进展   总被引:1,自引:0,他引:1  
首先总述了美国RZWQM的研制过程、模拟功能以及模拟的流程,随后分别介绍了RZWQM 6个主要过程:物理过程、土壤化学过程、养分过程、杀虫剂过程、作物生长过程和管理过程;讨论了模型应用过程的注意事项,并探讨了RZWQM98新版本特征;最后对RZWQM模型的应用进展进行了综述,认为RZWQM在模拟作物生长和水分、养分和杀虫剂在作物根区内的运移是很有用的工具。  相似文献   
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