凝析气井最小排液气体流量的计算方法

针对凝析气井井底积液的开采状况,该方法通过建立液滴模型并进行受力分析,推导出了计算从井底携带最大直径液滴的气体最小流速的公式,从理论上解决了气井积液的难题。现场实践证明,该计算方法是比较可靠、准确的。通过对三口气井的实验计算,均取得了成功。     

Analysis of GSM/GPRS Cell with Multiple Data Service Classes

This paper is concerned with the performance modelling and evaluationof a General Packet Radio Service (GPRS) for a wireless Global System forMobile telecommunication (GSM) cellinvolving both voice and multiple class data services under a completepartitioning scheme (CPS). The GPRS is modelled as a system ofaccess and transfer queues in tandem having an external multiple classcompound Poisson bursty traffic with geometrically distributedbatches under first-come-first-served (FCFS) and generalised processor-sharing(PS) scheduling disciplines, respectively. The proposed queueing model isvalid for both uplink and downlink connections and provides multiple classdata services with different arrival rates, interarrival-time squaredcoefficients of variation (SCVs), file (burst) sizes and different PSdiscrimination service levels.Based on the principle of maximum entropy (ME), a product formapproximation is characterised for the two queues in tandem, subject to queueing theoretic mean value constraints. The MEsolution implies a decomposition of the system into individual singleserver building block queues, each of which can be analysed inisolation. Consequently, ME closed form expressions and simulation resultsfor the aggregate state probability together with the marginal mean queuelength and blocking probability are divised to assess the credibility of theME solution and also to study the effect of external GPRS bursty traffic uponthe performance of the wireless cell.     

IPTV承载网技术的研究

简要介绍了IPTV系统结构以及IPTV承载网的现状,讨论了已建几种IPTV承载网中的传输路由技术,分析了优缺点,提出一个适应市场和运营需要的解决方案,展望了传输和路由的新技术.     

分析影响隧道围岩稳定性因素

主要对影响隧道围岩稳定性的自然因素如岩石性质及岩体的结构、岩体的天然应力状态、地质构造、地下水进行了详细的分析。     

Improved J and COD estimation by GE/EPRI method in elastic to fully plastic transition zone

It is well known that conventional GE/EPRI method over-estimates the J-integral and crack opening displacement (COD)¹ in the elastic to fully plastic transition zone. The present paper investigates this issue and attempts to rectify this error. An improved GE/EPRI method is proposed with the modifications of α (Ramberg-Osgood coefficient) term in the equation of plastic J and COD. The proposed method has been experimentally and numerically validated.     

万兆以太网交换芯片设计技术

中国以IP为核心的宽带城域网建设正处于高峰阶段,给10G以太网为核心的城域以太网解决方案提供巨大的应用舞台.为了满足中国数据通信市场的需求.中兴通讯研制了10GE以太网产品.文章对这一产品进行了介绍,对其核心芯片--10GE交换芯片进行了分析,给出了芯片的功能、关键技术及芯片功能.     

明代杰出的治黄专家——潘季驯

简述了明代治河专家潘季驯主持治理黄河的背景、思想体系和实施方略及献身精神     

GE90-70 PLC在循环氢压缩机C1101控制系统中的应用

本文介绍了GE90-70PLC在辽阳石化公司炼油厂循环氢压缩机C1101控制系统中的应用，在硬件配置、系统软件、用户程序生成方法及系统调试方面进行阐述。     

高层钢结构顺风向风振加速度的MTMD控制

根据我国荷载规范并利用虚拟激励法和振型降价法，建立了在风荷载作用下设置MTMD时高层钢结构建筑的加速度传递函数，进而导出了设置MTMD时高层钢结构建筑的加速度动力放大系数R明确表达式。MTMD的优化目标是为Min.Min.Max.R。通过最优搜寻可得到MTMD的最优参数及有效性指标。目前的论文通过考虑结构基本周期和离地10m高的平均风速的不同取值，研究其对MTMD最优参数及有效性指标的影响。     

基于反向复用技术的100G光传输的设计与实现

基于PDM-QPSK(偏振复用-正交相位调制)以及相干光加高速DSP技术的100G传输技术在骨干网的应用越来越成熟.然而,此100G传输方案价格依然昂贵,当采用100G应用于底层网络,例如接入网以及数据中心交换机的互联互通时,价格成本考量就显得尤为突出.提出了一种新型的100G传输方案,以反向复用技术与多通道分发(MLD-Multi Lane Distribution)技术为基础并实现了基于此方案的样机设计,并且完成了48小时的160 km的无误码传输测试.实验证明,此方案基于传统单模光纤的100G传输性能良好,且是真正实现了低成本的100G传输方案.