Interval Reliability and Optimum Preventive Maintenance Policy

This paper discusses an interval reliability R(x, T) of a 1-unit system with repair. The R(x, T) is derived explicitly for the case in which T and x are distributed exponentially. This paper also discusses the optimum preventive maintenance policies maximizing the limiting interval reliability when T is constant and maximizing the interval reliability when T has an exponential distribution.     

A Confidence Interval for the Barlow-Scheuer Reliability Growth Model

Barlow & Scheuer proposed a useful scheme for estimating reliability growth of a system undergoing developmental testing and offered a conservative lower s-confidence bound. This paper shows how a less conservative lower s-confidence bound can be found by using an equivalent model for system reliability.     

Interval Reliability of An n-Unit System With Single Repair Facility

This paper derives the interval reliability of an n-unit standby redundant system with warm standbys. The derivation uses renewal theory and regeneration-point techniques. The solution is obtained in the form of Laplace transforms; the transforms can be readily inverted for some special cases.     

Reliability Sampling Plans Under Progressive Type-I Interval Censoring Using Cost Functions

This paper gives a reliability sampling plan for progressively type I interval censored life tests when the lifetime follows the exponential distribution. We use the maximum likelihood method to obtain the point estimation of the parameter of failure time distribution. We provide an approach to establish reliability sampling plans which minimize the total cost of life testing under given consumer's and producer's risks. Some numerical studies are investigated to illustrate the proposed approach.      

HP-41C Programs for Bayesian Binomial and Exponential Interval Estimation with a Uniform Prior on the Reliability

HP-41C handheld calculator programs are presented for Bayes interval estimation of: 1) the reliability R of a component for binomial data; 2) both R and the MTBF for exponential data. In both cases, the ``ignorance' prior is employed: uniform on R over the range 0 to 1. The input data are numbers of trials and successes for the binomial case; and test time, mission time and failures for the exponential. This paper describes the models and includes the programs.     

Enabling multimedia applications for factory automation

Emerging multimedia communication and processing technologies enable many factory applications. However, these technologies are advancing at a prodigious pace. Therefore, designing, managing, and upgrading these networks within this fast-paced environment represents a formidable challenge. The various enabling technologies and the standards that control their use are the subject of this paper. Special emphasis is given to the use of these technologies to support developments on the factory floor. This strategy involves the use of video, audio, and data communications, as well as the inherent processing involved. The role that local area networks and the Internet play in the development of future factory applications is also discussed     

Enabling power management for network-attached computers

Power management is an emerging area of interest for network management. This article reviews current developments and describes methods for enabling power management in network-attached computers. © 1998 John Wiley & Sons, Ltd.     

扬声器的可靠性和可靠性试验

阐述了扬声器的可靠性和可靠性试验的主要问题,从试验目的、试验应力和失效数据等方面讨论了扬声器可靠性和可靠性试验,在扬声器的设计和制造阶段进行可靠性工作十分重要。     

SiGe为3G无线通信提供技术支撑

三代(3G)无线通信正在快速地变成现实.3G得以成功实施,一个重要的原因是在传输的两端扮演了支撑角色的锗硅(SiGe)双极和BiCMOS工艺技术.在手机中,SiGe在更低的电压下给射频(RF)发射机和接收机带来更快的速率,在支持3 G多媒体通信所必需的更高带宽的同时,保持功耗降低.基站也从SiGe受益:高速的数据转换器和运算放大器成功地用更宽的带宽处理更多的通道.虽然SiGe的基本特性对两种应用而言是相似的,但对应于每种应用背后的半导体工艺之间有差别.     

Enabling Technologies for Next-Generation Optical Packet-Switching Networks

The optical packet-switching network is considered to be one of the most promising solutions for end-to-end delivery of high-bitrate data, video, and voice signals across optical networks of the future. Optical label switching (OLS) technology incurs simpler extraction and processing of the labels so that the optical packets can be routed with low latency to the destinations. We have developed several key enabling technologies for integrated optical networks, including optical label generation, label swapping, optical buffering, clock recovery, and wavelength conversion. We have designed and experimentally demonstrated these enabling techniques that can provide efficient broadband services in future optical networks.     

Displays for Mobile Communications Enabling New Markets and Applications

Displays directly affect the functionality of wireless terminals andresulting applications available to users of next generation wirelessnetworks. Limitations in the human visual system and in direct viewdisplay technologies, enable a host of new types of display technologiesto be developed that offer original equipment manufacturers (OEMs) newproduct design opportunities. Without these advances in displaydevelopment, the complete multimedia experience of next generationnetworks will go unfulfilled. This paper describes the current state ofdisplay technology for the mobile communications market, illustratessome emerging technologies that show promise for incorporation in futuremobile terminals, and lastly elaborates on microdisplay technologies andhow they can enable the true 3G experience in mobile terminals.     

Enabling Components for Multi-Standard Software Radio Base Stations

Receiver and transmitter technology is an enablingfactor for the software radio concept, with analogueto digital conversion being the limiting performancefactor. The requirement for common hardware forseveral different systems leads to parameterizedmodules and higher integration levels. Moduledefinition is closely related to the architecturalchallenges of receiver design. Emerging multi-mode base stations favour larger hardware granularity. Thesoftware radio approach reduces the hardwarecomplexity of a cell site from several racks ofdiscrete single-channel radios to one or two shelvesof open architecture modules.This paper presents critical functional blocks forwide-band multi-mode base stations based on thesoftware radio concept. Major component specificationsare reviewed showing the implications on systemdesign. Functional and performance parameters foranalogue to digital converters (ADCs), digital toanalogue converters (DACs), digital down and upconverters are illustrated using specific products.Applications are presented by revisiting existingtransceiver architectures in the framework of nextgeneration wireless standards.     

为老式设备提供蓝牙支持的简单解决方案

随着蓝牙技术的应用不断增加,大规模消费类应用的范围和数量也日益明晰.目前,蓝牙技术主要应用于手机或耳机,当然,支持蓝牙功能的笔记本电脑和PDA也逐渐流行(参看图1).蓝牙技术的优点使得支持蓝牙的设备越来越多.但与许多基于新技术的产品一样,遗留系统(或称老系统)的存在使用户接受的速度受到一定的影响.     

Interval algorithm for homophonic coding

It is shown that the idea of the successive refinement of interval partitions, which plays the key role in the interval algorithm for random number generation proposed by Han and Hoshi (see ibid., vol.43, p.599-611, 1997) is also applicable to the homophonic coding. An interval algorithm for homophonic coding is introduced which produces an independent and identically distributed (i.i.d.) sequence with probability p. Lower and upper bounds for the expected codeword length are given. Based on this, an interval algorithm for fixed-to-variable homophonic coding is established. The expected codeword length per source letter converges to H(X)/H(p) in probability as the block length tends to infinity, where H(X) is the entropy rate of the source X. The algorithm is asymptotically optimal. An algorithm for fixed-to-fixed homophonic coding is also established. The decoding error probability tends to zero as the block length tends to infinity. Homophonic coding with cost is generally considered. The expected cost of the codeword per source letter converges to c¯H(X)/H(p) in probability as the block length tends to infinity, where, c¯ denotes the average cost of a source letter. The main contribution of this paper can be regarded as a novel application of Elias' coding technique to homophonic coding. Intrinsic relations among these algorithms, the interval algorithm for random number generation and the arithmetic code are also discussed     

Interval estimates for yield modeling

Follows statistical convention by calling estimates point estimates. Defect density is a random phenomenon; thus a function of defect density, namely yield, will also be a random variable. An analysis is proposed of the yield model that allows calculation of interval bounds for yield, based on flexible defect models. An examination is also made of the interval estimates for yield from an individual wafer, and the confidence intervals for average yield for a given type of wafer.     

Determining Component Reliability and Redundancy for Optimum System Reliability

The usual constrained reliability optimization problem is extended to include determining the optimal level of component reliability and the number of redundancies in each stage. With cost, weight, and volume constraints, the problem is one in which the component reliability is a variable, and the optimal trade-off between adding components and improving individual component reliability is determined. This is a mixed integer nonlinear programming problem in which the system reliability is to be maximized as a function of component reliability level and the number of components used at each stage. The model is illustrated with three general non linear constraints imposed on the system. The Hooke and Jeeves pattern search technique in combination with the heuristic approach by Aggarwal et al, is used to solve the problem. The Hooke and Jeeves pattern search technique is a sequential search routine for maximizing the system reliability, RS (R, X). The argument in the Hooke and Jeeves pattern search is the component reliability, R, which is varied according to exploratory moves and pattern moves until the maximum of RS (R, X) is obtained. The heuristic approach is applied to each value of the component reliability, R, to obtain the optimal number of redundancies, X, which maximizes RS (R, X) for the stated R.     

Optical Transceivers for Fiber-to-the-Premises Applications: System Requirements and Enabling Technologies

A comprehensive review of the optical transceivers for fiber-to-the-premises applications is presented, with emphasis on system requirements and enabling technologies. Recent progress in photonic integration to realize low-cost, high-performance, and compact optical transceivers for the optical network terminal is reviewed