BVW系列编辑录像机常见故障判别

ＢＶＷ系列编辑录像机是索尼公司广播级模拟分量式的。ＢＥＴＡＣＡＭＢＶＷ录像机一般在省级或较大市级电视台使用较多。下面以ＢＶＷ－７５Ｐ为列，就使用中常见的几种故障介绍一下自己的判断方法，以求迅速找出其故障部位，对症下药。ＢＶＷ型录像机和ＰＶＷ型录像机一...     

HDPE／顺丁橡胶共混材料磨蚀速率的研究

用自制的旋臂式磨蚀实验仪，研究了高密度聚乙烯（ＨＤＰＥ）／顺丁橡胶、高密度聚乙烯和４５＾＃钢在攀枝花尾矿矿浆中的磨蚀速率与磨蚀温度和磨蚀时间的关系。结果表明，在２０－４８℃时，Ｗ（ＨＤＰＥ／ｃｉｓ－ＢＲ）和Ｗ（ＨＤＰＥ）分别保持在０．１７－０．２０ｍｍ／ａ和０．２２－０．３０ｍｍ／ａ。在５５℃时，Ｗ（ＨＤＰＥ／ｃｉｓ－ＢＲ和Ｗ（ＨＤＰＥ）分别增加至０．２８和０．３９ｍｍ／ａ，在２０－５５℃时，Ｗ（     

用ASP技术实现企业WEB网页

目前在许多单位里,象ＷＯＲＤ、ＥＸＣＥＬ或ＷＰＳ该类文档文件已成为重要的数据信息资源,在ＩＮＴＲＡＮＥＴＷＥＢ平台上如何高效率地管理这些信息资源是一个需要解决的问题。本文是利用ＡＳＰ技术开发一个基于ＷＥＢ的应用程序,实现在ＷＥＢ页面上浏览目录文件,很轻易地做到诸如ＷＯＲＤ、ＥＸＣＥＬ和ＷＰＳ等文档文件的查阅和下载,大大地减少信息维护的工作量。     

国内期刊纵览

20 0 0 0 80 1　电沉积ＲＥ Ｎｉ Ｗ Ｐ Ｂ4 Ｃ ＰＴＦＥ———郭忠诚 .电镀与涂饰 (双月刊 ) ,2 0 0 0 ,19( 3 ) :1研究了ＲＥ Ｎｉ Ｗ Ｐ Ｂ4 Ｃ ＰＴＦＥ复合镀层的性能。结果表明 ,热处理温度对ＲＥ Ｎｉ Ｗ Ｐ Ｂ4 Ｃ ＰＴＦＥ复合镀层的硬度影响很大 ,当温度达到 40 0℃时 ,复合镀层的硬度达到极大值 ( 114 5ＨＶ) ;在同一热处理温度下 ,当保温时间达到 3ｈ ,镀层的硬度值最佳。当热处理温度达到 3 0 0℃时 ,ＲＥ Ｎｉ Ｗ Ｐ Ｂ4 Ｃ ＰＴＦＥ复合镀层的耐磨性最好。高温氧化试验表明 ,ＲＥ Ｎｉ Ｗ Ｐ Ｂ4 Ｃ ＰＴＦＥ复合镀层随氧化…     

高性能2.5Gb／s用的DFB—LD／EA单片集成器件

报导了采用全ＭＯＣＶＤ生长的１．５５μｍ的单片集成ＤＦＢ＝ＬＤ／ＥＡ组件的 在ＤＷＤＭ系统上的传输测试结果，出纤功率Ｐｆ≥２．５ｍＷ＠Ｉｆ＝７５ｍＡ，边模抑制比ＳＭＳＲ〉３５ｄＢ，调制器反向偏压为２．５Ｖ时的消光比为１４ｄＢ，该发射模块在２．５Ｇｂ／ｓＤＷＤＭ系统上进行了传输试验，传输２４０Ｋｍ后无误码，其通道代价≤１ｄＢ＠ＢＥＲ＝１０＾－１２。     

雅马哈GC2020BⅡ2路压缩／限幅器功能与操作

雅马哈ＧＣ２０２０ＢⅡ２路压缩／限幅器功能与操作张沁（１）ＰＯＷＥＲＳＷＩＴＣＨ（电源开关）：设备总开关。（２）ＬＩＮＫＳＷＩＴＣＨ（连接开关）：这个开关用来决定ＧＣ２０２０ＢⅡ是处于双路单声状态，还是处于立体声状态。在双路单声道状态时，通道１和通道...     

电位差计微机控制检定系统的软件设计

本介绍运用ＩＥＥＥ－４８８８接口，联接１０８１七位半数字万用表，应用ＧＷＢＡＳＩＣ语言，制作完成可对ＵＪ３３ａ，ＵＪ３６等便携式电位差计进行检定的微机辅助检定系统。     

α，ω－对乙氧羰氧基苯甲酸聚乙二醇酯液晶的合成及转变性能研究

用模型化合物的方法，合成了一系列含柔性间隔链段芳香聚醚酯液晶化合物（ＰＥＥＣＢ－ｎ），通过１ＨＮＭＲ、ＤＳＣ、正交偏光显微镜、ＷＡＸＤ等手段，对其结构和液晶态转变进行了表征。     

合金粉末柔性布的制备及微观结构研究

采用轧制工艺，将一定配比的合金粉末（ＮｉＣｒＢＳｉ粉、ＷＣ颗粒）与连结物混合制备成具有良好柔性的合金粉末布，用作钎涂层原材料。ＳＥＭ分析表明，在轧制过程中，颗粒状的连接物发生结构变化，形成纵横交错的纤维，成为合金粉末的载体。合金粉末的颗粒尺寸、形状对柔性的强度有影响     

电化学方法制备非晶态铬工艺的研究

本文研究了从三价铬电镀溶液中获得非晶态铬镀层的工艺，用ＥＤＸ和ＷＤＸ测定了镀层的组成，表明镀层是由铬和少量的碳组成：用Ｘ—射线衍射测定了镀层的结构；发现镀层在２θ为４３°时，有非晶态的特征峰“ＢｒｏｎｄＧａｕｓｉｏｎＰｅａｋ”；并且用ＥＧ＆ＧＰＡＲＣ电化学软件研究了电镀溶液的电化学行为。     

基于SQL Server的蛋白质二级结构预测样本集数据库的构建

基于SQL Server数据库管理系统,将蛋白质二级结构预测的样本集CB513、CB396和RS126组织起来,建立了数据库DataSet,并配置了一个IIS服务器以方便网络查询.该数据库将蛋白质二级结构预测样本集有效地组织起来,实现了规范化、结构化统一管理,便于存储、检索和分析数据,减少错误的发生.通过该数据库可以提取供蛋白质二级结构预测研究的样本、序列转换、变换编码以及分析评价预测结果等,取代许多传统编程处理文本文件的繁琐工作,大大提高效率,促进工作的开展.     

Apache服务器监控系统的研究

针对Apache服务器介绍了一个远程监控系统。它提供了有效的监控机制,使管理者及时了解服务器的工作状态及工作性能;其良好的管理界面使管理者从繁杂的命令行工作方式解脱出来,方便地进行管理;其安全的通信机制使监控系统与服务器异地运行而减少对服务器性能的影响。     

Linux下高性能网络服务器的设计

本文讨论了Linux下一种高性能网络服务器的设计,采用线程池和内存池技术,AIO技术和缓存技术以及消息队列可以大幅度提升系统性能,减少服务端开销,可胜任高负荷高吞吐量环境需求,测试表明该系统性能优势在高负荷情况尤其明显。     

邮件服务器过载问题的前置式过滤技术

针对邮件服务器由于垃圾邮件过多而造成超负荷问题,提出并设计了一前置式邮件过滤系统.该系统首先在路由器级上通过轻量级TCP指纹分析实现垃圾邮件检测和过滤,然后在邮件服务器上,通过IP地址行为判断进入服务器的邮件是否为垃圾邮件,以此来缓解或解决邮件服务器可能发生的过载问题.该设计具有计算简单、实现容易等特点.实验结果表明,这种前置式邮件过滤系统的可行性和有效性,是目前常规反垃圾邮件技术较好的补充.     

Minimizing the makespan for the two-machine scheduling problem with a single server: Two algorithms for very large instances

This article considers the problem of scheduling a given set of n jobs on two identical parallel machines with a single server. Each job must be processed on one of the machines. Before processing, the server has to set up the relevant machine. The objective is to minimize the makespan. For this unary NP-hard problem, two fast constructive algorithms with a complexity of O(n²) are presented. The performance of these algorithms is evaluated for instances with up to 10,000 jobs. Computational results indicate that the algorithms have an excellent performance for very large instances so that the obtained objective function values are very close to a lower bound, and in many cases even an optimal solution is achieved. Superiority over all existing algorithms is obtained by sequencing the jobs on the two machines so that the machine idle time and the server waiting time are minimized. In doing so, the characteristics of an optimal solution resulting from its relevant lower bound are taken into account.     

Studying the effect of server side-constraints on the makespan of the no-wait flow-shop problem with sequence-dependent set-up times

This paper deals with the problem of scheduling the no-wait flow-shop system with sequence-dependent set-up times and server side-constraints. No-wait constraints state that there should be no waiting time between consecutive operations of jobs. In addition, sequence-dependent set-up times are considered for each operation. This means that the set-up time of an operation on its respective machine is dependent on the previous operation on the same machine. Moreover, the problem consists of server side-constraints i.e. not all machines have a dedicated server to prepare them for an operation. In other words, several machines share a common server. The considered performance measure is makespan. This problem is proved to be strongly NP-Hard. To deal with the problem, two genetic algorithms are developed. In order to evaluate the performance of the developed frameworks, a large number of benchmark problems are selected and solved with different server limitation scenarios. Computational results confirm that both of the proposed algorithms are efficient and competitive. The developed algorithms are able to improve many of the best-known solutions of the test problems from the literature. Moreover, the effect of the server side-constraints on the makespan of the test problems is explained using the computational results.     

Fuzzy simulation approach to multi-task scheduling in uncertain distributed server systems

The efficient scheduling of tasks in distributed server systems is of great importance to minimise the response time and thus improve the performance of such systems. This paper presents an integrated fuzzy simulation approach to improve the performance of distributed server systems. Performance is defined in terms of time-varying distributions of job arrival, job parallelism and task service demand with fuzzy parameters. In order to achieve the most efficient policies for job scheduling in this fuzzy system, an integrated fuzzy simulation approach is used. This is the first study that uses fuzzy simulation for performance improvement of uncertain distributed server systems.     

Ameliorate Security by Introducing Security Server in Software Defined Network

Software Defined Network (SDN) deals with huge data processing units which possess network management. However, due to centralization behavior ensuring security in SDN is the major concern. In this work to ensure security, a security server has been at its aid to check the vulnerability of the networks and to keep an eye on the packet according to the screening policies. A Secure Shell Connection (SSH) is established by the security server which does a frequent inspection of the network’s logs. Malware detection and the Intrusion Detection System policies are also incorporated in the server for the effective scanning of the packets. In response to a suspicious log or the packets in the SDN network there is a change in the security norms. Hence the proposed work updates the security policies in accordance with the attacker mentality.     

实现PACS持续可用性的思路探讨与实施方案研究

目的解决PACS临床应用中PACS持续可用性的方案探讨。方法构建三重模块冗余配置的持续可用性影像服务器,通过其中的TMR表决器实现服务器核心的失效备援,由具有失效备援功能的SCSI接口分别连接镜像硬盘、RAID控制器和DLT控制器以形成CA影像服务器的完整系统架构,再用CA影像服务器取代PACS中可能的单一故障点（single point of failure,SPOF）组件。结果使整个PACS具有了99．999％的最高系统可用性比率。结论TMR类CA影像服务器的诸多优势,使其非常适宜于大型医学影像网络和数据库的应用。     

刀片服务器散热系统噪声实验研究

通过实验测量并且综合气动声学相关知识进行噪声源识别,根据实验得到的数据结果判断服务器的噪声主要来源是风扇的旋转噪声并且求得噪声的频率值。同时运用UG（Unigraphics）建立了服务器风扇框的CAD（Computer Aided Design）模型,运用CFD（Computational Fluid Dynamics）软件FLUENT针对风扇框的流场进行仿真研究,针对服务器的噪声源的特性以及流场模拟结果设计了一个吸声导流槽,并取得了满意的降噪效果。