关于管理信息化工作的思考

本文探讨在管理信息化工作的关键内容,分析了信息、信息工具与管理工作的关系,强调信息数据的重要性。认为信息是管理工作的主要内容,信息的载体从纸张介质向电磁介质转化,信息工具因此发生了重要变化。管理工作是对工作中产生的信息进行处理,信息量的大小决定了组织结构,信息的如何处理决定了管理的工作流程。管理信息化工作要从信息载体变化的前提出发,考虑这个转变所带来的各种困难,充分应用信息工具的各种资源。在管理信息化工作中应考虑企业的成本和效益。管理系统应从业务出发,打破部门的界限,从数据源头开始,着重考虑权限的榨制,增强灵活性和适应性。     

Large-scale fabrication of bioinspired fibers for directional water collection

Spider-silk inspired functional fibers with periodic spindle-knots and the ability to collect water in a directional manner are fabricated on a large scale using a fluid coating method. The fabrication process is investigated in detail, considering factors like the fiber-drawing velocity, solution viscosity, and surface tension. These bioinspired fibers are inexpensive and durable, which makes it possible to collect water from fog in a similar manner to a spider's web.     

送电线路跨越高速铁路迁移改造措施

随着国家扩大内需计划的深入开展,各地基础建设全面铺开,新建越来越多的高速铁路、高速公路或高等级公路,在这样的大环境下,无疑使得数量众多运行中的输电线路面临改造问题.这种输电线路的改造工作往往时间紧迫、数量众多,如若对改造中的一些相关影响因素考虑不周全,将会严重影响工期、制约整体工程的施工进度,甚至会影响到送电线路的安全...     

HULL GESTURE AND RESISTANCE PREDICTION OF HIGH-SPEED VESSELS

Since trim and sinkage are significant while vessels are advancing forward with high speed, the predicted vessel resistance based on restrained model theory or experiment may not be real resistance of vessels during voyage. It is necessary to take the influence of hull gesture into account for oredicting the resistance of high-speed ship. In the present work the resistance problem of high speed ship is treated with the viscous flow theory, and the dynamic mesh technique is adopted to coincide with variation of hull gesture of high speed vessel on voyage. The simulation of the models of S60 ship and a trimaran moving in towing tank with high speed are conducted by using the above theory and technique. The corresponding numerical results are in good agreement with the experimental data. It indicates that the resistance prediction for high speed vessels should take hull gesture into consideration and the dynamic mesh method proposed here is effective in calculating the resistance of high speed vessels.     

海上油田含聚合物污水水质对储层保护技术的影响

研究含聚合物(含聚)污水水质对储层的伤害为确定含聚污水回注储层的可行性提供了依据。以渤海绥中36-1油田含聚污水为例,利用偏光显微镜、扫描电镜、核磁共振仪等,通过岩心动态损害实验分别对污水中的乳化油、悬浮物和产出聚合物浓度及粒径中值进行了评价,分析了含聚污水回注对储层的伤害机理。结果表明,含聚污水中油、悬浮物、聚合物三者的协同作用是主要伤害源,且对储层的伤害程度随着单一水质指标的增大而增加;由于聚合物分子的吸附聚集作用而形成高强度的可变形团状集合体,是造成岩心孔隙喉道堵塞的关键因素;含聚污水进入储层对孔喉的堵塞形式是优先堵塞大-中孔喉,并逐步由内滤饼向外滤饼的堵塞形式转化。优化含聚污水水处理工艺及现行加药方式,是解决含聚污水处理问题的关键。     

利用紫外光刻技术进行SU8胶的研究

SU 8光刻胶优异的性能在MEMS技术的发展重得到了广泛的应用 ,已经成为MEMS研究中必不可少的方法之一。SU 8光刻胶能够进行厚度达毫米的结构研究工作 ,另一方面SU 8结构具有很好的侧面垂直结构 ,通过控制工艺参数 ,能够获得满意的SU 8胶结构。SU 8光刻胶已应用于LIGA技术的标准化掩模制造工艺和一些器件的研究工作。在SU8胶研究过程中 ,克服了许多技术难题 ,使得这一技术能够应用到实际的需要中。     

金属卤化物气体放电灯启动问题的探讨

本文介绍了分别改变灯内填充物含量即 NaI 和 ScI 含量的方法,探讨此变化与光源气体放电参数的关系,从而分析和研究金属卤化物灯的启动特性,从而寻求延长光源寿命的途径。     

A 22-kHz multibit switched-capacitor sigma-delta D/A converter with92 dB dynamic range

A time- and capacitor-multiplexing technique for use in a highly linear switched-capacitor multibit DAC in sigma-delta data converters is presented. The technique uses subintervals in the sample clock to deliver multiple charge packets to holding capacitors. It avoids distortion effects caused by mismatched capacitors and finite opamp gain. A five-level switched-capacitor DAC using the proposed technique was designed as part of an audio-band multibit sigma-delta D/A converter that achieved a dynamic range of 92 dB and a THD of -93 dB with a low oversampling ratio of 32. No trimming, calibration, or dynamic matching scheme was required. The five-level SC DAC has been fabricated in a 2-μm CMOS process, and testing confirmed the anticipated theoretical results     

交互电视与应用

交互电视（ITV）是一种基础结构。这种结构提供了为数众多的硬件、软件和应用平台，这一点很像INTERNET。INTERNET也是一种结构，在它的上面有很多的硬件（服务器、客户机、调制解调器）、软件（WWW浏览器、WWW服务器程序、电子邮件服务器、通讯协议）和服务（FTP、电子邮件、新闻组、WWW）。     

A multiple access scheme for multimedia traffic in wireless ATM

This paper proposes a multiple access scheme for the forthcoming wireless ATM (Asynchronous Transfer Mode) system. Such ATM compatible wireless systems are motivated by the rapidly increasing demand for wireless extensions to broadband networks, which are expected to support mixed broadband services including Constant Bit Rate (CBR), Variable Bit Rate (VBR), and Available Bit Rate (ABR) traffic. Since these different traffics have very different performance requirements, the multiple access scheme design is very challenging. In this paper, we propose a multiple access scheme called Dynamic Time Division Multiple Access with Piggybacked Reservation (DTDMA/PR), attempting to achieve higher statistical multiplexing efficiency in the mixed VBR/CBR/ABR traffic scenario. The basic idea is to exploit two levels of reservation. The first level deals with the isochronous nature of CBR and VBR traffic and the bursty nature of ABR traffic by using the ALOHA reservation procedure. The second level exploits the piggybacked reservation approach to cope with the dynamic feature of VBR traffic in order to increase the multiplexing efficiency. An analytical model is also developed in this paper and verified by simulation. Numerical examples are given to gain some insight into the protocol itself.