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931.
932.
以组件技术为基础 ,从软件工程的角度介绍了运用ASP技术 ,在Web服务器IIS4 0上 ,通过CDOforNTS组件 ,以网页的形式发送邮件的方法 ,给出了CDO与ADO相结合实现邮件批量发送的例子。  相似文献   
933.
本文以北华航天工业学院图书馆的电子显示屏的使用为例,介绍了高校图书馆电子显示屏通过一定的控制方式显示文字、图形、二维或三维动画、电视等各种信息的方法,实现文本、图像、视频等多种内容形式的播放,彰显出电子显示屏在图书馆对外宣传服务中的优越性。  相似文献   
934.
We study the structure and kinetic properties of slow-mode shocks near the plasma sheet boundary layer (PSBL) associated with magnetic reconnection by Cluster observation. The presence of slow-mode shocks is confirmed by traditional Rankine–Hugoniot (RH) analysis and Monte-Carlo shock fitting method. The Walén analysis, applied to the tailward flow associated with slow-mode shocks, also supports that plasma was accelerated across a Petschek-type slow-mode shock connected to the diffusion region. Back-streaming ions were observed on the shock layer, and cold ions were accelerated and heated by slow-mode shocks. In addition, whistler and electrostatic solitary waves were observed around the slow-mode shocks. These waves might be excited by the observed field-aligned electron beams near the shocks.  相似文献   
935.
Problems of regularization in celestial mechanics and astrodynamics are considered, and basic regular quaternion models for celestial mechanics and astrodynamics are presented. It is shown that the effectiveness of analytical studies and numerical solutions to boundary value problems of controlling the trajectory motion of spacecraft can be improved by using quaternion models of astrodynamics. In this second part of the paper, specific singularity-type features (division by zero) are considered. They result from using classical equations in angular variables (particularly in Euler variables) in celestial mechanics and astrodynamics and can be eliminated by using Euler (Rodrigues-Hamilton) parameters and Hamilton quaternions. Basic regular (in the above sense) quaternion models of celestial mechanics and astrodynamics are considered; these include equations of trajectory motion written in nonholonomic, orbital, and ideal moving trihedrals whose rotational motions are described by Euler parameters and quaternions of turn; and quaternion equations of instantaneous orbit orientation of a celestial body (spacecraft). New quaternion regular equations are derived for the perturbed three-dimensional two-body problem (spacecraft trajectory motion). These equations are constructed using ideal rectangular Hansen coordinates and quaternion variables, and they have additional advantages over those known for regular Kustaanheimo-Stiefel equations.  相似文献   
936.
在制品管理中条码技术的应用   总被引:2,自引:0,他引:2  
针对面向订单的单件、小批量生产制造企业,设计了一套条码数据采集系统,分析了主要运作流程和功能模块.在在制品的管理中提出了基于不同级别的工件生产状态定义,并给出了相应的加工、检验判定准则.经实际使用证明条码技术运用于工业现场是可行的.  相似文献   
937.
针对JL8飞机部分重要口盖防雨存在的问题,在查找和分析原因的基础上,提出了解决重要口盖防雨设计的改进措施。  相似文献   
938.
In this paper, a proper choice of technological parameters for a shot peening process is considered, namely, the shot diameter, shot blast velocity, density of shot material, and depth of a plastically deformed layer-depending on the material being processed. The data presented can be used in calculations of technological parameters of FV monolithic panel shaping.  相似文献   
939.
The results of a preliminary analysis of microperturbations on the International Space Station during physical exercises of the crew are presented. The goal of this paper is to identify the parameters of perturbations when physical exercises are performed. The results of measurements by sensors of microaccelerations of both Russian and American segments during physical exercises in the service module of the Russian segment are analyzed.  相似文献   
940.
In order to observe exoplanets we propose a space-based achromatic stellar coronagraph combined with a 0.8–1.5 m telescope. We develop an achromatic common path interferometer for observing an exoplanet (a faint off-axis source) on the background of a hoste star (bright axial source). An image of the star and its copy acquire an achromatic phase shift by 180° and interfere in antiphase. The achromatic phase shift is caused by geometric phase in the scheme of a three-dimensional interferometer. The interference process divides spatially the dark and light fields of the star image redirecting them to the opposite sides of a beam splitter. The interference process does not weaken the image of a planet, with equal intensities it is redirected to both sides of a beam splitter. The suggested scheme of common path interferometer ensures mechanical stability. The background signal is experimentally demonstrated to be reduced by six orders of magnitude.  相似文献   
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