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81.
本文简要介绍网上电子银行系统的基本结构。重点讲述信息传送服务器 ,并给出该系统的设计例。  相似文献   
82.
邱雪芹 《山东冶金》1997,19(3):18-20
本文阐述了在WINDOWS环境下开发电脑,电视、电话信息查询系统系统的基本思想、硬软件环境和具体实施方法,并介绍了软件流程。  相似文献   
83.
C.S. Li  P.K. Hopke 《Indoor air》1992,2(2):84-100
Air cleaning as a means of mitigating the risks arising from exposure to indoor radon progeny has been evaluated in a single-family house in the north eastem US. using an automated, semi-continuous activity-weighted size distribution measurement system. The measurements included radon concentration, condensation nuclei count, and activity-weighted size distribution of radon decay products. Measurements were made in the house with and without an operating air filtration system and with various particle sources common to normal indoor activities operating. Aerosols were generated by running water in a shower, candle burning, cigarette smoking, vacuuming, opening doors, and cooking. Using a room model, the changes in attachment rates, average attachment diameters, and deposition rates of the unattached fraction with and without the air cleaning system were calculated. In the presence of active aerosol sources, the air filtration unit typically reduced the concentration of particles within the hour following the end of particle generation. After candle burning, cigarette smoking, and vacuuming in the bedroom, the reductions of PAEC by air filtration are about 60% with the air filtration system operating in the bedroom. During cooking in the kitchen, the reductions of PAEC in the bedroom with the air filtration system were about 40%. However, for all cases the dose reductions were smaller than the particle and PAEC reductions. For those particles that were generated within the bedroom, there was a 20% to 50% reduction in dose. In the case of cooking where the door was open and particles infiltrated from the rest of the house, the dose reduction was only 5% on average and appears to be insignificant. Thus, the dose reductions were h e r than the reductions in activity concentration, but there were no cases where the estimated dose actually increased.  相似文献   
84.
A new principle and arrangement for directly determining the angle of incidence of an optical beam on an object are proposed and demonstrated. The novelty of the approach lies in the realization of a ‘smart object’, which extracts a portion of the incident beam's power into an optical waveguide attached to the object's surface or embedded in its body for converting the angle of incidence into the position of a guided beam with finite lateral extent. This ‘integrated optical light pointer’ beam is accomplished by means of creating additional degrees of freedom on the target in two different ways. While a first type is based on introducing spatial variations of the waveguide thickness, a second type makes use of a chirp of the grating periodicity. The feasibility for practical applications has been experimentally demonstrated by a direct comparison with a commercial high-resolution encoder, resulting in an r.m.s. error of <30′'. Measurements have been performed for chips fabricated based on replicated polycarbonate substrates and with no external optics, showing the great potential of this approach for realizing low-cost yet high-performance miniature goniometers.  相似文献   
85.
针对双组分等温平行反应体系,分析讨论了以提高催化剂活性和选择性为目标时催化剂活性组分的最优分布形式(为δ-函数分布),并给出了确定这种反应体系的催化剂的最佳活性层位置的计算方法。结果表明:以提高选择性为目标的最佳活性层位置比以提高活性为目标的要更靠近催化剂核心,实用的最优位置应介于二者之间。最后,本文还研究了反应动力学级数、本性选择性以及内扩散模数(Thiele 模数)等因素对最佳活性层位置的影响。  相似文献   
86.
87.
本文通过焊接试验对奥氏体不锈钢绕带容器环板与绕带焊接工艺进行了研究分析,并得出了合理的焊接方法和工艺参数。  相似文献   
88.
本文就如何发挥高校教研室的职能作用记述了本教研室所采取的具体方法和措施。  相似文献   
89.
A well‐known control system which can reduce the adverse effects of disturbances is a disturbance observer. However, in many cases of mechanical systems, system disturbances which do not satisfy the matching condition may be imposed. Therefore, it may be difficult to reduce the adverse effects of the disturbances by the traditional disturbance observer. In this paper, a method of control system synthesis for disturbance rejection using a dual observer is proposed. This method is based on the zeroing induced by the disturbance localization problem. This problem may be solved by dividing the state space into observable subspace and unobservable subspace. As compared with an H controller based on perfect observation, the usefulness of the proposed control system for disturbance rejection is demonstrated by numerical simulations for a two‐mass spring system. © 2002 Scripta Technica, Electr Eng Jpn, 138(4): 50–60, 2002; DOI 10.1002/eej.1138  相似文献   
90.
排气系统在注射模中的应用   总被引:2,自引:0,他引:2  
介绍了排气系统在注射模中的重要性,排气系统位置的选择,排气系统的种类以及应用等  相似文献   
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