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991.
为适应网络发展的需要 ,有线宽带运营商需要通过一套完整的宽带网络计费管理系统 ,从硬件到软件、从前台到后台对各个方面进行管理 ,实现统一、规范、快速的信息化、网络化电脑管理 ,降低运营成本 ,提高工作效率 ,以过硬的服务质量、优惠的价格、丰富的内容吸引用户。 相似文献
992.
The aim of this study was to demonstrate a correlation between the clinical assessment of narcissistic personality disorder in children and underlying self and object relationships. D. Westen's Social Cognition and Object Relations Scale for the Thematic Apperception Test (1995; D. Westen, N. Lohr, K. Silk, K. Kerber, & S. Goodrich, 1985) was used to compare the object representations of two groups of referred latency-aged children, one for whom narcissistic issues were thought to be primary. Support for the clinical literature, which describes these children as lacking in empathy, struggling with self-esteem regulation, and in poor control of their impulses or aggression, was found. Additionally, a tendency to have a vulnerable sense of identity and to be preoccupied with seeking out and developing relationships with others was found to differentiate these children from peers with similar behavioral and diagnostic profiles. Results obtained have potential implications for the assessment and treatment of narcissistically disturbed children. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
In this paper, we develop call admission control algorithms for SIR-based power-controlled DS-CDMA cellular networks. We consider networks that handle both voice and data services. When a new call (or a handoff call) arrives at a base station requesting for admission, our algorithms will calculate the desired power control setpoints for the new call and all existing calls. We will provide necessary and sufficient conditions under which the power control algorithm will have a feasible solution. These conditions are obtained through deriving the inverse of the matrix used in the calculation of power control setpoints. If there is no feasible solution to power control or if the desired power levels to be received at the base station for some calls are larger than the maximum allowable power limits, the admission request will be rejected. Otherwise, the admission request will be granted. When higher priority is desired for handoff calls, we will allow different thresholds (i.e., different maximum allowable power limits) for new calls and handoff calls. We will develop an adaptive algorithm that adjusts these thresholds in real-time as environment changes. The performance of our algorithms will be shown through computer simulation and compared with existing algorithms. 相似文献
994.
This paper presents a numerical study of piston-driven heat transfer and fluid flow in a plane channel containing a sudden
expansion. The numerical method employed is based on a control-volume-based finite element method for incompressible flow
with a staggered and moving grid and SIMPLER algorithm for pressure-velocity coupling. The numerical results show a good agreement
with the experimental data reported in the literature. Results concerning time and space evolution of the thermal and flow
fields are presented for different values of the expansion ratio, the initial clearance volume, and the piston velocity.
Received: 20 April 2002 / Accepted: 23 January 2003 相似文献
995.
996.
介绍了中国石化山西阳泉石油分公司实施市县石油公司一体化管理体制的工作经验。其具体做法是:采取措施使思想、业务流程和服务与之接轨,开展创省级“青年文明号”活动和加强企业文化建设;实施两级绩效考核,工资与油品吞吐量挂钩;坚持以人为本,长短结合,立足基础,整体提升;用抓好培训、责任和制度的落实及监管,来强化基础管理的效果。 相似文献
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Giovanni Giambene Enrico Zoli 《International Journal of Satellite Communications and Networking》2003,21(2):199-225
In this paper, we investigate a packet access scheme that is able to support mixed traffics in the presence of high propagation delays. Referring to a Time‐Code Division Multiple Access air interface, we propose a Medium Access Control (MAC) protocol based on a random access scheme. A successful attempt grants the use of a slot‐code resource. This protocol is named Adaptive Time Code‐Packet Reservation Multiple Access (ATC‐PRMA), since the access parameters are changed, depending on the traffic load conditions, so as to fulfil Quality of Service requirements. Numerical examples are carried out for the Low Earth Orbit (LEO)‐Mobile Satellite System (MSS) scenario, but all these considerations could be applied to High‐Altitude Platform Stations (HAPSs) as well. In both cases, high propagation delays prevent an immediate feedback to users. An analytical approach is proposed to study the stability of our MAC scheme. Accordingly, we define a criterion for optimizing system performance. The predicted ATC‐PRMA behaviour is supported by simulation results. Finally, we show the performance improvement of ATC‐PRMA with respect to a MAC protocol not employing adaptive parameters. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
1000.