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11.
本文以西峰油田董志区长8油藏为例,运用数值模拟技术,研究了水平井组合方式及其井网形式。研究结果表明,水平井是提高特低渗油藏开发效果的有效途径。结合长庆特低渗储层吸水性能好的特点,认为采用直井注水,水平段走向垂直于储层最大主应力方位的水平井采油的井网组合开发效果最佳。 相似文献
12.
针对连城锰矿4号矿段排土场的特点、影响稳定因素及可能产生的危害,在实践中采取了有效的管理措施,防止了排土场危害的产生,保证了排土场的稳定。 相似文献
13.
本文以渤中28-1(BZ28-1)油田N6H水平井为例,从多方面对该井的动态和产能变化进行了系统分析,所用的方法对水平井动态分析有一定的指导意义。 相似文献
14.
本文提出了一种广义最小均方(GLMS)算法,分析了GLMS算法的性能,并根据GLMS算法,导出一种自适应递归滤波(ARF)算法。在推导中,ARF算法避开了超稳定定理,从而考虑自适应系统的严格正实条件和Popov不等式是不必要的。计算机模拟表明ARF算法具有很高的收敛速度。 相似文献
15.
Multi-User MIMO Mobile CDMA Uplink System Employing Turbo Coding and Joint Detection Through a Multipath Rayleigh Fading Channel 总被引:1,自引:1,他引:0
Yasmine A. Fahmy Hebat-Allah M. Mourad Emad K. Al-Hussaini 《Wireless Personal Communications》2006,38(3):325-341
In this paper, a generalized multiple-input multiple-output (MIMO) antenna system that can be fitted to the uplink of a wireless communication system is considered for the general case of multi-user. At the transmitter, the information bits are Turbo coded, then interleaved and passed through a serial-to-parallel converter. The channel is assumed bad urban suffering from multipath Rayleigh fading resulting in inter-symbol and multiple access interferences (ISI and MAI). At the front-end of the receiver, a number of receiving antennas are used followed by a joint multi-user estimator based on the Minimum Mean Square Error Block Linear Equalizer (MMSE-BLE).Computer simulations demonstrate a significant performance improvement in both single user and multi-user cases.This paper depends in parts on that presented at the 11th European Wireless Conference, Cyprus, Nicosia, pp. 187–192, April 2005.
Yasmine A. Fahmy was born in Guiza, Egypt, on June 4, 1976. She received the B.Sc., M.Sc. and Ph.D. degrees in Communication and Electronics engineering from Cairo University, Egypt on 1999, 2001 and 2005 respectively. She is presently an assistant professor at Cairo University, Egypt. Her current field of interest is wireless communication and channel estimation.
Hebat-Allah M. Mourad received her B.Sc., M. Sc. and Ph.D. degrees in electrical communication engineering from Cairo University, Egypt, in 1983, 1987 and 1994 respectively. Since 1983, she has been with the Department of Electronics and Communications, Faculty of Engineering, Cairo University, and is currently associate professor there. Her research interests include optical fiber communications, mobile and satellite communications.
Emad K. Al-Hussaini received his B.Sc degree in Electrical Communication Engineering from Ain-Shams University, Cairo, Egypt, in 1964 and his M.Sc and Ph.D. degrees from Cairo University, Giza, Egypt, in 1974 and 1977, respectively. From 1964 to 1970, he was with the General Egyptian Aeroorganization. Since 1970, he has been with the Department of Electronics and Communications, Faculty of Engineering, Cairo University, and is currently professor there. He was a research fellow at Imperial College, London, UK, and at the Moore School of Electrical Engineering, University of Pennsylvania, Philadelphia, PA, USA, in the academic years 1976/1977 and 1981/1982, respectively. In 1990, he received the Egyptian national encouragement award for outstanding engineering research. He has written several papers for technical international journals and conferences. His research interests include signal processing, fading channel communication, modulation, and cellular mobile radio systems. Dr Al-Hussaini is a senior member of IEEE. He is listed in Marquis Whos Who in the World and in the IBC (International Biographical Center, Cambridge) for outstanding people of the 20th century. 相似文献
16.
云台山隧道进口黄土段施工技术 总被引:2,自引:2,他引:0
从防排水、边仰坡支护、洞口加固、洞内超前支护、钢拱架锚喷联合支护等方面详细介绍了云台山隧道进口黄土段的施工技术,总结了该隧道的施工效果,强调了黄土隧道施工中防排水超前支护预注浆、施工监控的作用,积累了隧道施工经验. 相似文献
17.
改造加热炉系统 提高加热炉热效率 总被引:3,自引:0,他引:3
孙英才 《石油化工设备技术》1998,19(6):21-23
分析了重整装置加热炉热效率低的原因,介绍了提高加热炉热效率采取的几项措施。 相似文献
18.
介绍了双焊缝方矩形钢管生产技术的特点及冷弯等边槽钢孔型设计参数.通过双焊缝方矩形钢管用冷弯等边槽钢的孔型设计、生产,实现了大截面双焊缝方、矩形钢管的生产,满足了客户的需求. 相似文献
19.
In this paper we present an efficient technique for piecewise cubic Bézier approximation of digitized curve. An adaptive breakpoint detection method divides a digital curve into a number of segments and each segment is approximated by a cubic Bézier curve so that the approximation error is minimized. Initial approximated Bézier control points for each of the segments are obtained by interpolation technique i.e. by the reverse recursion of De Castaljau's algorithm. Two methods, two-dimensional logarithmic search algorithm (TDLSA) and an evolutionary search algorithm (ESA), are introduced to find the best-fit Bézier control points from the approximate interpolated control points. ESA based refinement is proved to be better experimentally. Experimental results show that Bézier approximation of a digitized curve is much more accurate and uses less number of points compared to other approximation techniques. 相似文献
20.
塔里木油田水平井优化设计方法及跟踪效果评价 总被引:8,自引:5,他引:3
塔里木油田坚持“稀井高产”的开发原则,不仅利用水平井技术实现了新油田整体高效开发,而且在老油田综合调整中也取得了巨大成效,还成功应用于气藏及凝析气藏的开发,以水平井技术为主实现了气田开发高水平和高效益,逐渐形成了一套比较成熟的适合塔里木气区实际的水平井优化设计技术。 \r\n 相似文献