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81.
确定保障能力薄弱环节对提高部队保障能力至关重要,目前保障能力薄弱环节确定有指标评估得分法和权重法两种方法,两种方法均存在一定的片面性。针对存在的问题,提出一种基于指标裕度空间和权重的求指标薄弱度的方法查找、确定保障能力薄弱环节,并且将集对分析的思想应用到指标优化和指标裕度空间的分析求取上,使指标薄弱度更加精确。最后结合某基层一级保障单位进行实例,运用Matlab软件仿真模型,进行保障能力指标薄弱度分析,并与目前存在的两种方法对比分析,实践证明所提出的方法更适用于保障能力薄弱环节的确定。 相似文献
82.
随着国家3G牌照的发放,支持3G移动通讯的设备开发已经成为通讯产业和嵌入式系统发展的热点.嵌入式Linux因其源代码开放、可定制等特点而在嵌入式系统开发中得到广泛应用,而基于3G通讯模块的设备驱动是开发3G终端设备和服务的基础.文中讨论了嵌入式Linux环境下的设备文件管理、USB系统结构,详细分析了USB驱动骨架,并结合arm系列S3C2440处理器和支持TD-SCDMA的通讯模块LC6311,实现嵌入式Linux系统下的3G通讯模块设备驱动开发,并给出了测试验证实例. 相似文献
83.
Fault tolerant control for singular systems with actuator saturation and nonlinear perturbation 总被引:1,自引:0,他引:1
In this paper, the problem of robust fault tolerant control for a class of singular systems subject to both time-varying state-dependent nonlinear perturbation and actuator saturation is investigated. A sufficient condition for the existence of a fixed-gain controller is first proposed which guarantees the regularity, impulse-free and stability of the closed-loop system under all possible faults. An optimization problem with LMI constraints is formulated to determine the largest contractively invariant ellipsoid. An adaptive fault tolerant controller is then developed to compensate for the failure effects on the system by estimating the fault and updating the design parameter matrices online. Both of these two controllers are in the form of a saturation avoidance feedback with the advantage of relatively small actuator capacities compared with the high gain counterpart. An example is included to illustrate the proposed procedures and their effectiveness. 相似文献
84.
Yi-Wei Ci Zhan Zhang De-Cheng Zuo Zhi-Bo Wu Xiao-Zong Yang 《Information Processing Letters》2010,110(5):182-187
In fault-tolerant computing, the approach of causal message logging provides on-demand stable logging and enables the independent recovery of nodes. It imposes the requirement that the dependency between non-deterministic events needs to be known for nodes. The dependency information is disseminated through messages. A central problem in traditional causal message logging is that if the message logging progress of nodes cannot be effectively tracked, some redundant dependency information will be piggybacked on the messages. In this paper, a dependency mining based approach is proposed. It tries to detect the message logging progress of nodes only from the dependency between non-deterministic events, without needing to piggyback an additional dependency vector or dependency matrix on each message. 相似文献
85.
深入分析了论域变化与决策表条件信息熵的变化原理,在此基础上提出一种新的决策表属性约简算法. 该算法通过不断将决策表中一定属性集下协调的部分从论域中去除,把不协调的部分作为新的论域做进一步处理,逐步减少参与属性约简的对象数,可以在一定程度上降低求取属性约简的计算量,实验数据表明该算法是高效的. 相似文献
86.
This paper addresses the analysis problem of asymptotic stability for a class of uncertain neural networks with Markovian jumping parameters and time delays. The considered transition probabilities are assumed to be partially unknown. The parameter uncertainties are considered to be norm-bounded. A sufficient condition for the stability of the addressed neural networks is derived, which is expressed in terms of a set of linear matrix inequalities. A numerical example is given to verify the effectiveness of the developed results. 相似文献
87.
A robust scheduling method is proposed to solve uncertain scheduling problems. An uncertain scheduling problem is modeled by a set of workflow models, and then a scheduling scheme (solution) of the problem can be evaluated by workflow simulations executed with the workflow models in the set. A multi-objective immune algorithm is presented to find Pareto optimal robust scheduling schemes that have good performance for each model in the set. The two optimization objectives for scheduling schemes are the indices of the optimality and robustness of the scheduling results. An antibody represents a resource allocation scheme, and the methods of antibody coding and decoding are designed to deal with resource conflicts during workflow simulations. Experimental tests show that the proposed method can generate a robust scheduling scheme that is insensitive to uncertain scheduling environments. 相似文献
88.
Heng Qi Yuhong Liu Xuan Wang Feng Shen Yong Yu Tao Chen Tiechuan Zuo 《Microsystem Technologies》2009,15(2):297-300
Excimer laser ablation technique was introduced into this work to fabricate a passive planar micromixer on the PMMA substrate.
T-junction shaped and width-changed S-shaped microchannels were both designed in this micromixer to enhance mixing effect.
The mixing experiment of distilled water and Rhodamine B with injection flow rate of 500 and 1,500 μm/s validates the mixing
effectivity of this micromixer, and indicates the feasibility of excimer laser ablation in the microfabrication of μ-TAS device. 相似文献
89.
This paper investigates the robust finite-time consensus problem of multi-agent systems in networks with undirected topology. Global nonlinear consensus protocols augmented with a variable structure are constructed with the aid of Lyapunov functions for each single-integrator agent dynamics in the presence of external disturbances. In particular, it is shown that the finite settling time of the proposed general framework for robust consensus design is upper bounded for any initial condition. This makes it possible for network consensus problems to design and estimate the convergence time offline for a multi-agent team with a given undirected information flow. Finally, simulation results are presented to demonstrate the performance and effectiveness of our finite-time protocols. 相似文献
90.
学校教学机房大多是采用服务器+有盘工作站架构的局域网,局域网络的安全对保障基于计算机的教学十分重要.本文介绍了保护Windows NT局域网网络安全的一些措施,通过我系局域网运行情况来看,较好的保证了网络的安全,为我系教学提供了良好的保证. 相似文献