智能动态网络资源分配系统

通过对解决GSM移动通信网络热点区域话务拥塞问题的研究，提出了利用可控功分器实现智能动态网络资源的分配，解决不同种类的话务拥塞问题，并着重讨论了该系统目前的成功运用及前景。     

Uplink Scheduling in CDMA Packet-Data Systems

Uplink scheduling in wireless systems is gaining importance due to arising uplink intensive data services (ftp, image uploads etc.), which could be hampered by the currently in-built asymmetry in favor of the downlink. In this work, we propose and study algorithms for efficient uplink packet-data scheduling in a CDMA cell. The algorithms attempt to maximize system throughput under transmit power limitations on the mobiles assuming instantaneous knowledge of user queues and channels. However no channel statistics or traffic characterization is necessary. Apart from increasing throughput, the algorithms also improve fairness of service among users, hence reducing chances of buffer overflows for poorly located users. The major observation arising from our analysis is that it is advantageous on the uplink to schedule “strong” users one-at-a-time, and “weak” users in larger groups. This contrasts with the downlink where one-at-a-time transmission for all users has shown to be the preferred mode in much previous work. Based on the optimal schedules, we propose less complex and more practical approximate methods, both of which offer significant performance improvement compared to one-at-a-time transmission, and the widely acclaimed Proportional Fair (PF) algorithm, in simulations. When queue content cannot be fed back, we propose a simple modification of PF, Uplink PF (UPF), that offers similar improvement. Hereafter, we refer to users with low recieved power at the base even when transmitting at peak transmit power as “weak” users, and the strongly recieved users at the base as “strong” users. Krishnan Kumaran is currently a member of the Complex Systems Modeling section in the Corporate Strategic Research of ExxonMobil Corp., Clinton, NJ. Formerly, he was a Member of Technical Staff in the Mathematics of Networks and Systems Research Department at Bell Labs in Murray Hill, NJ, where his research interests were in modeling, analysis and simulation of design, resource management and scheduling issues in telecommunication networks. Lijun Qian is an assistant professor in the Department of Electrical Engineering at Prairie View A&M University. He received his B.S. from Tsinghua University in Beijing, M.S. from Technion-Israel Institute of Technology, and Ph.D. from WINLAB, Rutgers University, all in electrical engineering. Before joining PVAMU, he was a researcher at Networks and Systems Research Department of Bell Labs in Murray Hill, NJ. His major research interests are in wireless communications and networking technologies, especially in radio resource management, protocol design, TCP/RLP optimization and MPLS traffic engineering.     

Poly(vinyl pyrrolidone)—C70 complexes in aqueous solutions

Aqueous solutions of poly(vinyl pyrrolidone)-fullerene complexes (PVP-C₇₀) have been studied using static and dynamic light scattering methods. Two diffusive processes were detected. The slow diffusion was interpreted as dynamics of large intermolecular PVP-C₇₀ complexes while the fast diffusion was associated with the presence of individual PVP molecules in solution. It was also shown that the molecular weights and dimensions of PVP-C₇₀ complexes are smaller than for PVP-C₆₀ by a factor of 2.5-3. In aqueous solutions of PVP-C₇₀ complex the depolarization and dissymmetry of scattered light were observed in contrast to PVP-C₆₀ solutions. It reveals the existence of anisotropic structures in PVP-C₇₀ solutions. Intermolecular interactions within PVP-C₇₀ complexes are weak and a hydrodynamic field can destroy complexes.     

A Bluetooth Based Sensor Network for Civil Infrastructure Health Monitoring

Communicating with sensors has long been limited either to wired connections or to proprietary wireless communication protocols. Using a ubiquitous and inexpensive wireless communication technology to create Sensor Area Networks (SANs) will accelerate the extensive deployment of sensor technology. Bluetooth, an emerging, worldwide standard for inexpensive, local wireless communication is a viable choice for SANs because of its inherent support for some of the important requirements – low power, small form factor, low cost and sufficient communication range. In this paper we outline an approach, centered on the Bluetooth technology, to support a sensor network composed of fixed wireless sensors for health monitoring of highways, bridges and other civil infrastructures. We present a topology formation scheme that not only takes into account the traffic generated by different sensors but also the associated link strengths, buffer capacities and energy availability. The algorithm makes no particular assumptions as to the placement of nodes, and not all nodes need to be in radio proximity of each other. The output is a tree shaped scatternet rooted at the sensor hub (data logger) that is balanced in terms of traffic carried on each of the links. We also analyze the scheduling, routing and healing aspects of the resulting sensor-net topology.     

网格资源管理系统模型研究

网格资源管理系统是网格计算系统的重要组成部分。文章分析了网格资源管理系统的功能需求，具体论述了该模型的原型系统，最后介绍了相关研究工作。     

论建立动态勘探目标评价体系的迫切必要性

从国际上通行的油气勘探评价工作重点,中国石油所面临的"已逐步进入一个不断在老区范围内开展精细勘探、在老区范围内开展新区块、新层系勘探以获得主要的储量增长"的新的勘探形势,现有地质研究中各专题研究与具体勘探目标评价脱节等多个方面,论述了在中国石油内部建立一套动态勘探目标评价体系的迫切必要性;并在此基础上阐述了一个完整的动态勘探目标评价体系应包括的主要内容;最后对该体系的建设进行了可行性分析。     

爆破震动作用下新浇基础混凝土的安全震动速度研究

针对新浇筑混凝土的爆破震动控制,设法利用爆破地震波(Rayleigh波)作用下的新浇筑基础混凝土受力状态的理论分析和动力有限元计算,确定的新浇筑混凝土中的震动速度及动拉应变分布,并结合不同龄期下新浇筑混凝土的允许极限拉应变,从理论上确定新浇筑基础混凝土的安全震动速度及主要影响因素.理论分析结果和计算实例表明,新浇筑基础混凝土的允许震动速度值随基岩对新浇筑混凝土的基础约束程度的提高和随混凝土强度的降低而降低,我国现行采用的新浇筑大体积混凝土基础面上的质点安全震动速度值具有较大的安全储备.     

Scheduling Algorithms for Packet-Oriented MAC Protocols in Wireless Multimedia Systems

Future generation wireless multimediacommunications will require efficient Medium AccessControl (MAC) protocols able to guarantee suitable Qualityof Service (QoS) levels for different traffic classes whileachieving a high utilization of radio resources. This paperproposes a new scheduling technique to be adopted at the MAClevel in wireless access systems, named Dynamic Scheduling-Time DivisionDuplexing (DS-TDD), that efficiently managesvideo, voice, Web and background traffics. A theoretical approachis proposed in this paper to evaluate the DS-TDD performance withvoice and Web traffics. Simulation results have permitted tohighlight the following promising characteristics of the DS-TDDscheme: (i) a high capacity of real-time traffics isattained with a QoS insensitive to Web and background trafficloads; (ii) a high throughput can be guaranteed whilepreserving the QoS levels of the different traffic classes;(iii) heavier downlink traffic loads do not modify the QoSof uplink traffics. Finally, extensive comparisons with differentscheduling schemes proposed in the literature have permitted tohighlight the better performanceof DS-TDD.     

动态矩阵控制在浆料浓度控制系统中的应用

针对PTA生产中浆料配制过程这一有纯滞后、大时间常数的非线性系统，进行系统的动态机理分析，与工作点附近的线性化，在此基础上设计DMC-PID串级加前馈控制方案。目前该系统在扬子石化化工厂PTA装置上已成功投运。     

生存能力技术及其实现案例研究

生存能力技术谋求增强系统在面临攻击、失效等灾难情况下仍能继续提供服务的能力。本文提出了以多样化分布式动态备份技术和主动漂移机制为手段，以被保护目标的机动性和隐蔽性为目的的生存能力技术模型。提出了多样化体系理论及其实现案例，基于该理论设计并实现了自适应TOM方法。最后通过模拟和测试探讨了生存能力的评价方法，并验证了本文的结果。