气象装备供应保障管理系统的改进与完善

以J2EE技术为核心,根据国家级、省级用户的需求,从增加省级库、国家级查询全国气象装备数据库、自动入库、自动盘点等方面对原气象装备供应保障系统进行了升级完善。该系统在新疆气象技术装备中心投入试验与使用,结果表明:该系统能够实现省级可增加本级气象装备库、装备调拨自动入库以及库存自动盘点等多种功能,满足了省级、国家级不同用户的需求,为未来全国气象装备信息化管理奠定了基础。     

科技政策实施效果的模糊综合评价

针对科技政策实施效果影响因素具有复杂性和随机性且其评价有一定难度这一问题,在分析现有评价方法的基础上,引入价值准则指标,建立了科技政策实施效果评价指标体系,采用模糊综合评价方法对某市科技政策实施效果进行了评价.     

大牛地气田大98井区水平井开发技术政策研究

大牛地气田剩余未动用储量大部分为Ⅱ—Ⅲ类低品位储量,水平井开发将是气田产能建设的主要方式。因此,优化研究多级压裂水平井开发技术政策很重要。基于多级压裂水平井数值模拟概念模型,对单井设计、压裂缝、井网和井距进行研究,结果表明:单井水平段延伸方向应垂直于最大主应力方向,水平段位于气层中部最好,压裂缝尽量穿过含气砂体并以锯齿型分布最优,平均压裂半缝长为158 m,平均压裂缝间距为112 m,采用排状交错井网最优。结合数值模拟法、动态分析法及经济评价法,确定大98井区合理井距为1 000~1 200 m,根端距为700 m。     

关于对矿山5G网络的安全接入的研究

本文对矿山5G网络的安全接入的重要性进行了分析,从矿山5G网络基础设施的安全方案、支持数据机密性、权限管理以及敏感信息保护四个方面提出了矿山5G网络的安全接入措施。     

High‐performance execution of service compositions: a multicore‐aware engine design

Although modern computer hardware offers an increasing number of processing elements organized in nonuniform memory access (NUMA) architectures, prevailing middleware engines for executing business processes, workflows, and Web service compositions have not been optimized for properly exploiting the abundant processing resources of such machines. Amongst others, factors limiting performance are inefficient thread scheduling by the operating system, which can result in suboptimal use of system memory and CPU caches, and sequential code sections that cannot take advantage of multiple available cores. In this article, we study the performance of the JOpera process execution engine on recent multicore machines. We first evaluate its performance without any dedicated optimization for multicore hardware, showing that additional cores do not significantly improve performance, although the engine has a multithreaded design. Therefore, we apply optimizations on the basis of replication together with an improved, hardware‐aware usage of the underlying resources such as NUMA nodes and CPU caches. Thanks to our optimizations, we achieve speedups from a factor of 2 up to a factor of 20 (depending on the target machine) when compared with a baseline execution ‘as is’. Copyright © 2012 John Wiley & Sons, Ltd.     

一类输电网损分摊方法的积分路径相关性简析

利用功率微增量进行求和是目前输电损耗分摊中的一类代表性方法。文中讨论了该类方法所存在的积分路径相关性问题,表明等步长划分积分区间本身即是一类特殊且并无明显理论依据的求和(积分)路径,至少到目前为止,尚无相关理论可以支持这类特解在理论体系上的恰当性。对该类方法而言,如何克服其所存在的求和路径相关性问题仍然是一个开放的、有待解决的问题。     

变电站远程维护系统的多用户接入控制

随着无人变电站自动化程度的提高,充分利用变电站的网络通信的硬件资源,完善自动化系统．变电站远程维护系统RMS(Remote Maintenance System)已经在某些地区实现。变电站自动化对信息互换的需求．使得远程用户的Internet接入成为可能。因此RMS多用户的安全接入成为迫切需要解决的问题。通过分析RMS的多用户结构。提出了利用远端拨号认证RADIUS(Remote Authentication Dial In User Service)协议的网络接入方案。开发了基于角色的权限控制RBAC(Role Based Access Control)模型的权限分配．严格限制用户的权限。     

Dr．COM认证环境下Internet接入共享与仿真

为了满足企业内、外网之间灵活访问的需求,设计了一个改进的Internet接入共享方案,基于路由和远程访问服务和网络地址转换技术,成功实现了Dr．COM宽带认证环境下主机和移动终端的网络接入共享,并在VMware虚拟机上仿真某企业网络．改进后的方案,无需购置专用硬件路由器,具有成本低、软硬件可扩充性强、组网灵活等优点,尤其适用于中小型企业,并为工程技术人员研究In—ternet接入提供了有益参考．     

Major oil exporters may profit rather than lose, in a carbon-constrained world

The Organization of Petroleum Exporting Countries (OPEC) claims compensation for losses in expected oil export revenues due to CO₂ mitigation measures in developing countries. These losses are expected for two primary reasons: a reduction in the consumption of oil in importing countries and a reduction in the producer price of oil (taxation in an importing country implies a transfer of rents from producers to consumers). So far, most studies have focused on these two mechanisms and corroborated that revenue losses for OPEC are to be expected. However, there are also mechanisms that may be expected to raise the price of oil products. In a cost-effective regime for dealing with climate change, i.e., a regime in which all or most countries participate and in which the same carbon price is applied on all carbon-emitting activities, the cost of using unconventional oil, or synthetic diesel from coal, will increase even more than the cost of using conventional oil. Given that reserves of conventional oil are expected to dwindle over time, heavy oils and coal to liquids might set the long-run price for liquid fuels, which means that the price of oil would increase beyond the carbon fee; i.e., the rent on conventional oil would increase. We use an energy-economic optimization model to analyze these three mechanisms. We find that the net present value of OPEC revenue from conventional oil increases slightly (at most by 4 percent) with a global CO₂ restriction regime. We also consider conditions under which this result does not hold.     

Sensitivity and Coding of Opportunistic ALOHA in Sensor Networks with Mobile Access

We consider a distributed medium access protocol, Opportunistic ALOHA, for reachback in sensor networks with mobile access points (AP). We briefly discuss some properties of the protocol, like throughput and transmission control for an orthogonal CDMA physical layer. We then consider the incorporation of necessary side information like location into the transmission control and numerically demonstrate the loss in throughput in the absence of such information. Through simulations, we discuss the robustness and sensitivity of the protocol under various modeling errors and propose strategies to allow for errors in estimation of some parameters without reduction in the throughput. For networks, where the sensors are allowed to collaborate, we consider three coding schemes for reliable transmission: spreading code independent, spreading code dependent transmission and coding across sensors. These schemes are compared in terms of achievable rates and random coding error exponents. The coding across sensors scheme has comparable achievable rates to the spreading code dependent scheme, but requires the additional transmission of sensor ID. However, the scheme does not require the mobile AP to send data through the beacon unlike the other two schemes. The use of these coding schemes to overcome sensitivity is demonstrated through simulations. Parvathinathan Venkitasubramaniam was born in India in 1981. He received his B.Tech. degree from the department of Electrical Engineering, Indian Institute of Technology, Madras in 2002. He joined the School of Electrical and Computer Engineering, Cornell University, Ithaca, NY, in 2002 and he is working toward his Ph.D. degree. He is a recipient of the 2004 Leonard G. Abraham Award (with S. Adireddy and L. Tong) from the IEEE Communications Society. His research interests include random-access protocols,sensor networks, and information theory. Srihari Adireddy was born in India in 1977. He received the B.Tech. degree from the Department of Electrical Engineering, Indian Institute of Technology, Madras, and M.S. and Ph. D. degrees from the School of Electrical and Computer Engineering, Cornell University, Ithaca, NY in 2001 and 2003 respectively. Currently, he is working at Silicon Laboratories, Austin, TX. He is a recipient of the 2004 Leonard G. Abraham Award (with P. Venkitasubramaniam and L. Tong) from the IEEE Communications Society. His research interests include signal processing, information theory, and random-access protocols. Lang Tong received the B.E. degree from Tsinghua University, Beijing, China, in 1985, and M.S. and Ph.D. degrees in electrical engineering in 1987 and 1990, respectively, from the University of Notre Dame, Notre Dame, Indiana. He was a Postdoctoral Research Affiliate at the Information Systems Laboratory, Stanford University in 1991. Currently, he is a Professor in the School of Electrical and Computer Engineering, Cornell University, Ithaca, New York. Dr. Tong received Young Investigator Award rom the Office of Naval Research in 1996, and the Outstanding Young Author Award from the IEEE Circuits and Systems Society in 1991, the 2004 IEEE Signal Processing Society Best Paper Award (with M. Dong), the 2004 Leonard G. Abraham Prize Paper Award from the IEEE Communications Society (with P. Venkitasubramaniam and S. Adireddy). His areas of interest include statistical signal processing, adaptive receiver design for communication systems, signal processing for communication networks, and information theory.