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891.
Zuochang Ye Wenjian Yu Zhiping Yu 《Microwave Theory and Techniques》2006,54(5):2128-2137
An efficient algorithm for extraction of three-dimensional (3-D) capacitance on multilayered and lossy substrates is presented. The new algorithm presents a major improvement over the quasi-3-D approach used in a Green's function-based solver and takes into consideration the sidewalls of 3-D conductors. To improve the efficiency of the computation and the transformation of the Green's function, a nonuniform grid is adopted. The most computationally intensive part in the transformation of the Green's function is computed separately as technology-independent matrices Tk foremost. Once computed, Tk can be stored and used for any technology, thus the storage requirement and computational complexity are reduced from O (S/sup 2/) and O (S/sup 2/ log S/sup 2/), respectively, to just O [(log S/sub max/)/sup 2/]. Extensive tests have been performed to verify the new algorithm, and its accuracy has been established by comparing with other programs. 相似文献
892.
重点阐述了我国现代民营陶瓷企业在财务管理环境与财务管理实践中存在的弊端,从加强对现代民营陶瓷企业的财务管理体制研究、无形资产管理问题研究、知识资本及其所有者参与民营陶瓷企业收益分配问题研究和国际财务管理问题研究等四个方面提出了对策。 相似文献
893.
In order to study the influence of cerium ion implantation on the aqueous corrosion behavior of zircaloy-4, specimens were implanted by cerium ions with a fluence range from 1×1016 to 1×1017 ions/cm2 at maximum 150°C, using MEVVA source at an extracted voltage of 40 kV. The valence and elements penetration distribution of the surface layer were analyzed by X-ray photoelectron spectroscopy (XPS) and auger electron spectroscopy (AES) respectively. Glancing angle X-ray diffraction (GAXRD) was employed to examine the phase transformation due to the cerium ion implantation in the oxide films. Three-sweep potentiodynamic polarization measurement was employed to value the aqueous corrosion resistance of zircaloy-4 in a 1 N H2SO4 solution. It was found that a significant improvement in the aqueous corrosion behavior of zircaloy-4 implanted with cerium ions compared with that of the as-received zircaloy-4. The improvement effect will declined with raising the implantation fluence. The bigger is the fluence, the less is the improvement. Finally, the mechanism of the corrosion behavior of the cerium-implanted zircaloy-4 is discussed. 相似文献
894.
拉远基站与系统设备的互联互通 总被引:1,自引:0,他引:1
随着3G牌照发放日期的逐步临近,人们对第3代移动通信(3G)的认识也更加清晰.2G与3G将融合发展,平滑过渡.2G业务增长的数据显示,2G还有很大的发展空间,2G与3G的过渡将是一个长期的过程.3G将首先在一些热点地区、业务量大的地方优先使用,在开始的时候没有必要大规模铺网,只需采用一些拉远基站就可以解决这些地区的3G覆盖问题.文章从网络应用的角度论述了拉远基站在未来3G组网中的重要作用,分析了目前部署3G拉远基站可能存在的问题,对互联互通、站址和网管等问题的解决方法提出了建议. 相似文献
895.
S. Yu. Panov Yu. N. Shapovalov Yu. V. Krasovitskii A. A. Rusanov 《Chemical and Petroleum Engineering》2006,42(11-12):706-709
Pneumopulse regeneration of bag filter has been investigated, and based on it a regression equation for regeneration efficiency has been derived. It has been shown that pulse pressure exerts the dominant influence on the regeneration efficiency. 相似文献
896.
研究了18种具有不同孔结构参数的粒状铜基甲醇合成催化剂孔隙率对有效扩散系数的影响。结果发现,催化剂微孔孔隙率增大,曲节因子亦增大,扩散阻力增加。将孔隙率与催化剂曲节因子关联,得到了半经验方程,用它可估算催化剂的曲节因子。 相似文献
897.
基于SIP协议的IP电话增值业务实现技术 总被引:3,自引:0,他引:3
讨论了SIP协议以及基于SIP协议的IP电话增值业务实现技术 ,并对SIPCGI、CPL、SIPServlets、JAINAPIs等几种SIP编程技术进行了分析与比较 ,归纳总结了开发IP电话增值业务的一般方法 相似文献
898.
E. V. Chernyshev E. N. Veprov V. A. Petrov S. L. Bogdanov T. Yu. Levina T. I. Petrova V. I. Kashinskii A. A. Zonov A. E. Verkhovskii 《Power Technology and Engineering (formerly Hydrotechnical Construction)》2006,40(1):34-37
Results of a study of tube specimens cut from hot-water boilers show that film-forming octadecyl amine (ODA) used in the process
of preservation removes deposition from the surface of the metal. An ODA film is preserved on the surface after repeated washing
of the latter with hot water. The concentration of chlorides at the surface of the metal after treatment with ODA is lower
than before the treatment.
__________
Translated from élektricheskie Stantsii, No. 11, November 2005, pp. 15–18. 相似文献
899.
Though the airborne laser scanning (ALS) technique is becoming more popular in many applications, horizontal accuracy of points scanned by the ALS is not yet satisfactory when compared with the accuracy achieved for vertical positions. One of the major reasons is the drift that occurs in the inertial measurement unit (IMU) during the scanning. This paper presents an algorithm that adjusts for the error that is introduced mainly by the drift of the IMU that renders systematic differences between strips on the same area. For this, we set up an observation equation for strip‐wise adjustments and completed it with tie point and control point coordinates derived from the scanned strips and information from aerial photos. To effectively capture the tie points, we developed a set of procedures that constructs a digital surface model (DSM) with breaklines and then performed feature‐based matching on strips resulting in a set of reliable tie points. Solving the observation equations by the least squares method produced a set of affine transformation equations with 6 parameters that we used to transform the strips for adjusting the horizontal error. Experimental results after evaluation of the accuracy showed a root mean squared error (RMSE) of the adjusted strip points of 0.27 m, which is significant considering the RMSE before adjustment was 0.77 m. 相似文献
900.