Optimal Replacement Policy for Cold Standby System

Investigators are attracted by the complexity and significance of preventive maintenance problem,and there are hundreds of maintenance models and methods to solve the maintenance problems of companies and army,going with a lot of investigative harvests. However,one-component system or series system is focused by most of the literature.The problem of preventive maintenance（PM） on cold standby repairable system does not attach importance despite the fact that the cold standby repairable system is ubiquitous in engineering systems.In this paper,an optimal replacement model for gamma deteriorating system is studied.This methodology presented uses a gamma distribution to model the material degradation,and the impact of imperfect maintenance actions on system reliability is investigated.After an imperfect maintenance action,the state of a degrading system is assumed as a random variable and the maintenance time follows a geometric process.A maintenance policy（N）is applied by which the system will be repaired whenever it experiences the Nth PM,and an optimal policy（N~＊） could be determined numerically or analytically for minimizing the long-run average cost per unit time.A numerical example about how to confirm the optimal maintenance time by the inspecting information of liquid coupling device is given to demonstrate the use of this policy.This paper presents a condition-based replacement policy for cold standby repairable system under continuous monitoring.Its contribution embody in two aspects,relaxing the restrictions of hypothesis and investigating the condition-based maintenance policy of the cold standby repairable system which is ignored by others.

Optimal Apparoch for Replacement Intervals of Warm Standby System

The protection device with low price and high maintenance cost can be used for a long time.In order to improve availability of protection system,a method of increasing redundancy and periodic replacement is proposed.Firstly,the equivalent model of cumulative failure probability was established.Then,the wasting time of the spare part is converted into the working time of the using part.Considering the optimization objective,under the strategy of block replacement,the availability model in infinite period with the maximum availability and the cost model in finite period with the minimum cost are established separately.In this case,we seek out the optimum replacement interval and verify the applicability and validity of the model through contrast and analysis.Finally,the paper gives a brief discussion of future research area about warm standby system maintenance.

Bayesian and Multiple Bayesian Analysis of the Reliability Performances for Series System with Cold Standby Units

By using Bayesian and multiple Bayesian method, the failure probability, reliability and mean time to failure(MTTF) of series system with cold standby units are estimated. At last, we compare the two estimators by means of Monte_Carlo simulation.

Availability and Profit Optimization of Series-Parallel System with Linear Consecutive Cold Standby Units

In this paper, we study availability and profit optimization of a series-parallel system consisting of three subsystems A, B and C in which A and B are cold standby. Subsystem A consists of linear consecutive k-out-of-n units while subsystems B and C consist of a single unit each. The system works if any of A or B and C work. The objective of this study is to maximize the steady-state availability and profit. To solve the optimization problem, different numbers of units for n = 2, 3, 4, 5 in subsystem A are considered. Explicit expressions for busy period of repairmen, steady-state availability and profit function are derived using linear first order differential equations. Several cases are analyzed graphically for n = 2, 3, 4, 5 to investigate the effects of various system parameters on availability and profit. The paper also presents graphical comparison for specific values of system parameters and finds that the optimal system configuration is when n = 5.

Reliability analysis for a cold standby system under stepwise Poisson shocks

In this paper,a two-dissimilar-component cold standby repairable system maintained by a repairmanis investigated.The system fails due to either intrinsic factors or external shocks.Assume that shocks arrive according to a stepwise Poisson process,the intensity of which varies with respect to the number of failures of the working component.Repair after failure is imperfect.Using the supplementary variable method and the vector Markov process theory,we obtain some important reliability index for the system.By the renewal reward theorem,an optimal replacement policy N∗is derived by minimising the average cost rate of the system.Numerical examples are presented to validate the theoretical results.

Standby Redundancy Allocation for a Coherent System under Its Signature Point Process Representation

Willing to work in reliability theory in a general set up, under stochastically dependence conditions, we intend to characterize a not identically spare standby redundancy operation through compensator transform under a complete information level, the physic approach, that is, observing its component lifetime. We intend to optimize system reliability under standby redundancy allocation of its components, particularly, under minimal standby redundancy. To get results, we will use a coherent system representation through a signature point process.

Oracle standby database的建立与维护

Standbydatabase是oracle数据库的一种有效容错方式,可用来进行数据灾难恢复。详细介绍了Standbydatabase的建立过程和如何对Standbydatabase进行维护,并给出了常见问题的解决方法。

Sybase Replication server Warm Standby复制技术及其应用

提出了一套较完善的、基于数据库级的数据复制技术;分析了SybaseReplicationserverWarmStandby的技术优势、特征和适用范围;并具体描述了该前沿技术在实际应用中的实现过程。

STRUCTURES OF SYSTEMS WITH EXPONENTIAL LIFE DISTRIBUTIONS

Structures of monotone systems and cold standby systems with exponen-tial life distributions and dependent components are studied. It is shown that a mono-tone system composed of components with multivariate HNBUE life distributions isessentially a series system composed of components with multivariate exponential lifedistributions. Also, it is proved that for cold standby systems composed of componentswith multivariate NBU life distributions, all but oue of the components are degenerateat zero while the remaining one is exponential. In addition, several equivalent char-acterizations of multivariate exponential distribution are provided in the multivariateHNBUE life distribution class which include many existing results as special cases.

基于西门子网络设备的某港口工业以太网环网冗余应用

环网冗余以及双环网络之间的Standby连接,提供了工业生产体系中部署标准化、融合和安全的网络,为使用工业物联网奠定了坚实基础。相比传统的通信错误恢复机制,能够在正常通信链路发生故障时,利用冗余路径保证实时数据通信不间断,更好地满足高实时高可靠性的应用场景。

经济适用的医院冗灾信息系统建设利用ORACLE STANDBY建设医院冗灾系统

近几年,随着医院信息化建设的快速发展,很多医院都上了HI(S医院信息系统)、LI(S检验信息系统)以及PAC(S医学影像系统)。计算机的应用几乎渗透到医院的所有部门。在高度信息化医院中,网络中心如果出现重大事故(如:系统崩溃、火灾等)造成数据丢失。这将给医院带来的损失将是无法想象的。所以医院信息化建设中,冗灾系统的建设是重要的组成部分。

Simulation realization of skip cycle mode integrated control circuit in the switching power supply with low standby loss

This paper explores and proposes a design solution of an integrated skip cycle mode （SCM） control circuit with a simple structure. The design is simulated and implemented with XD10H-1.0μm modular DIMOS 650 V process. In order to meet the requirement of a wide temperature range and high yields of products, the schematic extracted from the layout is simulated with five process corners at 27℃ and 90℃. Simulation results demonstrate that the proposed integrated circuit is immune to noise and achieves skipping cycle control when switching mode power supply （SMPS） works with low load or without load.

An Improved SOI CMOS Technology Based Circuit Technique for Effective Reduction of Standby Subthreshold Leakage

Silicon-on-insulator (SOI) CMOS technology is a very attractive option for implementing digital integrated circuits for low power applications. This paper presents migration of standby subthreshold leakage control technique from a bulk CMOS to SOI CMOS technology. An improved SOI CMOS technology based circuit technique for effective reduction of standby subthreshold leakage power dissipation is proposed in this paper. The proposed technique is validated through design and simulation of a one-bit full adder circuit at a temperature of 27℃, supply voltage, VDD of 0.90 V in 120 nm SOI CMOS technology. Existing standby subthreshold leakage control techniques in CMOS bulk technology are compared with the proposed technique in SOI CMOS technology. Both the proposed and existing techniques are also implemented in SOI CMOS technology and compared. Reduction in standby subthreshold leakage power dissipation by reduction factors of 54x and 45x foraone-bit full adder circuit was achieved using our proposed SOI CMOS technology based circuit technique in comparison with existing techniques such as MTCMOS technique and SCCMOS technique respectively in CMOS bulk technology. Dynamic power dissipation was also reduced significantly by using this proposed SOI CMOS technology based circuit technique. Standby subthreshold leakage power dissipation and dynamic power dissipation were also reduced significantly using the proposed circuit technique in comparison with other existing techniques, when all circuit techniques were implemented in SOI CMOS technology. All simulations were performed using Microwindver 3.1 EDA tool.

“Standby” EMT and “immune cell trapping” structure as novel mechanisms for limiting neuronal damage after CNS injury

The central nervous system （CNS） contains the two most important organs, the brain and spinal cord, for the orchestration of the mental and physical activities of life. Because of its importance, the human body has evolved barrier systems to protect CNS tissue from the external environment. This barrier is a membrane composed of tightly apposed cells and is selectively permeable to specific molecules by way of membrane transporters.

Economic Assessment of Standby Diesel Generator for Peak Reduction in Commercial and Industrial Buildings:A Case Study in Malaysia

This paper outlines the barriers and potential benefits of using standby diesel generators in mitigating the peak demands for commercial and industrial customers. The feasibility of utilizing the standby diesel generators to reduce the electricity bills for customers is carried out by using the hybrid optimization model for electric renewable(HOMER)software. The size of the standby diesel generator and its operational duration are determined based on the lowest cost of electricity obtained from the evaluations. The economic assessments demonstrate that there is potential to reduce the electricity bills for commercial and industrial customers under the existing fuel price and tariffs. The commercial customers under the tariff C2 have the highest potential to save their electricity bills with the use of standby diesel generators for peak reduction. This study demonstrates the potential of the standby diesel generators in peak reduction.

Optimization of a Multi-node System Reliability Model

In order to improve the reliability of an electronic or a computer system, redundant components always need to be added as part of the system. When an active component falls, a standby component will be activated to guarantee the system in operation continuously. The standby component and the switching device have been usually assumed to be continuously functional duriv,g the setup of the reliability model. In fact, it is these two asstuxtptions that induce deviations during modeling and introduce variances for the system reliability design. Through modeling and optiming the dependability of the synchronous clock system that decomposed from a multi-node system, a new reliability model which takes these two elements into consideration has been developed. Simulation results demonstrate that the upgraded reliability model is closer Io the actual dependability of the real system. The capability of the system reliability design is also improved as a result.

New Hybrid Digital Circuit Design Techniques for Reducing Subthreshold Leakage Power in Standby Mode

In this paper, four new hybrid digital circuit design techniques, namely, hybrid multi-threshold CMOS complete stack technique, hybrid multi-threshold CMOS partial stack technique, hybrid super cutoff complete stack technique and hybrid super cutoff partial stack technique, have been proposed to reduce the subthreshold leakage power dissipation in standby modes. Techniques available in literature are compared with our proposed hybrid circuit design techniques. Performance parameters such as subthreshold leakage power dissipation in active and standby modes, dynamic power dissipation and propagation delay, are compared using existing and proposed hybrid techniques for a two input AND gate. Reduction of subthreshold leakage power dissipation in standby mode is given more importance, in comparison with the other circuit design performance parameters. It is found that there is reduction in subthreshold leakage power dissipation in standby and active modes by 3.5× and 1.15× respectively using the proposed hybrid super cutoff complete stack technique as compared to the existing multi-threshold CMOS (MTCMOS) technique. Also a saving of 2.50× and 1.04× in subthreshold leakage power dissipation in standby and active modes respectively were observed using hybrid super cutoff complete stack technique as compared to the existing super cutoff CMOS (SCCMOS) technique. The proposed hybrid super cutoff stack technique proved to perform better in terms of subthreshold leakage power dissipation in standby mode in comparison with other techniques. Simulation results using Microwind EDA tool in 65 nm CMOS technology is provided in this paper.

Advanced Burst Mode Control to Reduce the Standby Power of Flyback Converter

This paper we proposed advanced burst mode control technique to reduce the standby power consumption of the switch mode power supply (SMPS). To reduce the standby power consumption, most of the converter use burst mode or skip mode control technique. However Conventional standby mode control techniques have some problems such as audible noise and poor regulation. In proposed techniques, basically, the burst mode control technique is employed to reduce the fundamental switching frequency while limiting the peak drain current. But, in proposed technique, to improve the regulation characteristic, burst period of the proposed technique is shorter than that of the conventional burst mode technique. And also, to reduce the switching loss increase due to the short burst period, burst switching signal of the proposed technique is partially skipped. By using proposed advanced burst mode control technique, calculated standby power is 0.695W while standby power of the conventional burst mode control is 1.014W.

ORACLE Standby数据库工作原理及程序设计

通过分析ORACLE Standby数据库的建立、维护和应用的方法,相对于其他的Oracle产品的设置,Standby数据库的技术是简单的,容易设置的。探讨如何将Standby与Rman、Flashback等技术相结合,建立一套更为行之有效的数据安全容灾方案。

StandbyServer 32:开始供货

许多网络管理者想得到一种随 时可用的、热替换式服务器的安全性,但功能强大的Novell公司的SFT Ⅲ的高昂价格又使他们犹豫。幸运的是Vinca公司的StandbyServer32可以提供一个可靠的、价格合理的替代方案,它能在服务器失效时使您的用户得以恢复并继续运行。 StaadbyServer 32(ISA总线式的2599美元,EISA总线或微通道式的2999美元)应用NetWare的磁盘镜像特征通过高速连接把你服务器上的数据备份到另外的机器上。如果一台服务器垮掉了,你可以把服务器操作移向第二台PC机,然后在几分钟内重新连接你的用户。 与SFT Ⅲ不同的是第二台PC机不必与主服务器相同。