光盘刻录DIY

刻录前的准备很多朋友对刻录光盘有错误的认识,认为只要买好点的空白片（如金盘）就可十拿九稳,一旦刻盘失败,就认定是光盘刻录机的问题。其实不然,有时,刻录前的准备工作可以起到事半功倍的效用。首先在ＣＭＯＳ设置里关闭防毒功能和省电功能;其次,在Ｗｉｏｎｄｏｗｓ９５／９８里关闭电源保护功能和屏幕保护程序;再次,在刻录光碟前先对存放所要刻录的资料的硬盘进行查错和整理;最后在Ｗｉｎｄｏｗｓ９５／９８里尽量减少常驻内存程序,特别要关闭防火墙功能。至此刻录前的准备工作算是基本完成了。不过有一点笔者认为还是有必要…     

磁光盘录音机及其发展

本文介绍了磁光盘录／放的基本原理原理，简介了ＢＩＲＴＶ‘９７展出的三种磁光盘录音机，展望了磁光盘技术和磁光盘录音机今后的发展。     

An electrostatically suspended contactless platform

Electrostatic suspension of a silicon disk with explicit control of the lateral translational degrees-of-freedom is reported. The transduction subsystem configures electrode pairs to exert electrostatic forces on the disk and to also measure differential capacitances related to the disk position. Disk sidewall forcing electrodes are not necessary to control the disk’s lateral position because tilting the disk relative to the plane of the electrodes exerts lateral forces on the disk. Despite the fact that the disk’s lateral and angular degrees-of-freedom are strongly coupled, the system is not strongly stabilizable using only the disk’s vertical position and tilt estimates derived from electrode–disk gap measurements. Nevertheless, a stabilizing controller is proposed and lateral position measurements are added for regulating the disk’s in-plane position. Extensive experimental results corroborate the model and analysis.     

碟片式激光烧蚀微推力器靶盘利用率优化

碟片式激光烧蚀推力器的总冲与靶盘上烧蚀点数量线性相关,提高靶盘利用率有利于在有限的靶面上得到更多的烧蚀点。为了优化靶盘利用率,文中首先对激光烧蚀微推力器进行了结构设计和分析,对靶盘上的烧蚀点分布问题进行了理论建模,提出了串珠法和套圈法两种分析方法,分别设计了圆圈路径、螺旋路径和六角密排三种实际烧蚀点分布方式。通过计算,分析比较了三种分布方式下,靶盘尺寸和烧蚀点尺寸对靶盘利用率的影响规律。结果表明,六角密排的靶盘利用率理论最高可达90.64%,圆圈路径和螺旋路径的靶盘利用率理论最高可达78.54%;靶盘利用率受到靶盘尺寸和烧蚀点尺寸的影响,靶盘尺寸较小时,圆圈路径的靶盘利用率相对较大,靶盘尺寸较大时,六角密排的靶盘利用率较大;三种分布方式各有特点,在应用上各有侧重。该研究为充分利用碟片式激光烧蚀推力器的靶盘提供了理论指导和设计参考,对推力器的工程化设计有一定借鉴意义。     

Technology decomposition theory and magnetic disk technology

Technical change in the magnetic disk technology is investigated in light of technology decomposition theory proposed previously by the author (see ibid., vol.36, no.1, p.37-46 (1989)). The trends that provide the technical and technological measures of cost performance are presented. The technology decomposition for magnetic disk technology is postulated and the constituent values computed. Technology decomposition theory and the findings from disk technology evolution are discussed. The constituent values for magnetic disk technology are the same as have been found previously. The transfer ratio for magnet disk technology is the same as the transfer ratio found previously for microelectronics technology. The characteristics of technical change, i.e. initial effect, manufacturing constituents and concavity, are also present in the technical change of magnetic disk technology     

光盘信息符统计特性的激光散斑测试

采用激光散斑的方法研究了CD光盘的刻录质量.由于标志光盘信息符的凹凸结构导致了光盘表面微结构的光学粗糙性,光盘不同区域被激光照射后在测量空间形成散斑图像,通过分析光盘不同区域产生的散斑图的统计相关性及对比度值的变化,对光盘的刻录质量进行了定性研究.结果显示,刻录质量好的光盘,其不同区域的散斑相关性好,散斑对比度值高且起...     

ESD SPICE model and measurements for a hard disk drive

A simple lumped RLC model for a hard disk drive is developed and used in SPICE circuit simulations. Simulation results were compared with experimental measurements using a special “hybrid” disk drive to validate the SPICE model. The voltage on and between the head and disk inside the drive were modeled during an ESD event to the baseplate and/or disk. Experimental measurements and SPICE modeling show that if the disk grounded when there is a large disk-to-base resistance, then head-to-disk electrical breakdown can occur. It is concluded that an electrical model is valuable in developing an understanding of the effects of ESD on a hard disk drive.     

磁盘阵列上虚拟磁盘的管理

随着计算机技术的发展,数据量急速增如,数据管理成为一个研究热点。磁盘阵列的出现极大地改善了数据管理的性能。在使用磁盘阵列时,往往把它划分为多个逻辑磁盘,磁盘的大小不能改变。这种方法降低了磁盘空间的利用效率。为了解决这个问题,可以把磁盘阵列划分为一个或多个共享存储池。每个共享存储池管理多个虚拟磁盘。这些虚拟磁盘共同使用共享存储池的磁盘空间。为了协调多个虚拟磁盘同时向共享存储池读写数据的问题,设计了一个调度算法。使用这种方法,实现了对磁盘阵列的有效管理。     

Analysis of repair algorithms for mirrored-disk systems

This paper analyzes the effects of several disk-repair algorithms (DRA) for a mirrored disk subsystem (RAID-1). The main interest is in disk faults and how the repair-process copies data, for user requests, `from a fault-free disk to a spare disk' with the least performance-degradation. This study compares how various DRA affect system performance. Two DRA are compared and two access patterns (uniform and nonuniform) are studied to establish their effects on the repair process and performance. Sector faults are repaired using the reassign block facility in the SCSI protocol. When the `mean load of the disk subsystem is moderate' and the `sector repair time is of the same order of magnitude as the mean disk request processing time', then the differences between various DRA are minor. Simulation results indicate that the performance degradation of user disk requests can be reduced by introducing a short delay in the repair algorithm, A new algorithm (DRA 3) for detecting sector faults is presented. It scans the disk space, while no user disk-requests are issued, and using the advanced statistics of SCSI disks detects deteriorated media. Its advantage is that it can repair the disk subsystem before data are actually lost due to a media defect     

Resonance characteristics of whispering-gallery modes in anelliptic dielectric disk resonator

This paper presents a novel calculation method for resonance characteristics of an elliptic dielectric disk resonator. In the elliptic resonator, electromagnetic energy propagates as a whispering gallery (WG) mode along the edge region of the dielectric disk. In the novel analysis, a local propagation constant of the WG mode at each point of the elliptic disk edge is represented by a propagation constant of a WG mode in a circular disk whose radius of curvature, material constants, and thickness are equal to those of the elliptic disk. Therefore, we can easily calculate the resonance characteristics of the elliptic dielectric disk resonator by applying a conventional technique for the circular dielectric disk. The calculated results of the resonant frequencies and field distribution are well confirmed by experiments     

一种管理磁盘存储空间的新方法

本文提出并探讨了一种管理磁盘存储空间的新方法－区间管理法（ＩＭＭ）。这种方法把磁盘存储空间视为若干连续块区间的集合，将物理上连续的空间分配给每个写请求，这为高速存取提供了支持。文中给出了ＩＭＭ的分配和回收算法流程，并作了可行性模拟。模拟结果表明，ＩＭＭ是一种有效的盘空间管理方法。     

浅谈RAID技术与硬盘存储技术的发展

硬盘容量的不断加大使得存储视频的介质从盘到硬盘、从盘带播出过滤到应用视频服务器成为现实，但如何保证硬盘存储与播出的安全性和稳定性呢？为此简要介绍了RAID技术的发展以及如何解决硬盘存储和播出的安全和稳定问题。