一种用于网络安全的过滤代理服务器

随着对万维网使用的增多 ,人们对网络的有效性、性能和安全更加关注。目前 ,事实上因特网上的所有用户都是易受攻击的 ,网络安全问题已经成为人们关注的焦点 ,并对计算机和电信工业带来了恐慌。本文论述了一种过滤式代理服务器设计和实现的细节。通过该代理服务器 ,防火墙后面的客户系统可以有效地访问Web服务器 ,并且其本身安全并不受到威胁。此外 ,本文还介绍了一种通过删除GIF动画来克服带宽瓶颈问题和通过地址转换来解决IP地址紧缺的方法。     

利用WINDOWS实现“Internet”连接共享方案的设计与实现

针对局域网中“Internet”连接共享 ,提出了一种利用Windows新特性共享上网的方案 ,实现了“Internet”连接共享。较以前采用Wingate、Sygete等软件做一个代理服务器的方法速度更快 ,实现更方便 ,并节省了系统资源     

军工企业引入市场竞争机制的难点与对策

党的十六大明确提出了“深化国防科技工业体制改革.坚持寓军于民,建立健全竞争、评价.监督和激励机制.增强自主创新能力.加快国防科技和武器装备发展”的指示和要求。我们要进一步解放思想.大胆实践.开拓创新.努力把握社会主义市场经济的内在要求和运行特点,自觉遵循客观规律,坚持军民结合.寓军于民.促进军民良性互动.协调发展。建立和完善寓军于民的新体制和四个机制.核心和关键是要建立和完善市场竞争机制.打破封闭垄断,通过市场竞争合理配置和有效利用军工资源。     

评功评奖“三大件”

军功章 刚入伍的新兵,有两大愿望.一是摸 枪.二是戴军功章.紧握钢枪是军人的使命, 胸前有枚军功章是军人的荣誉.兵们的胸中 写满荣誉感和使命感.部队才会有战斗力. 第一次和军功章照面,总是悴然心动 的.心河似投入一粒石子溅起水珠泛起层 层波浪,渴望化为火焰在心头烘烤.看看 摸摸兵们幻现出自己戴军功章的情景 想像咀嚼个中的滋味.之后,闪闪的军功 章会常在眼前浮现.梦中的空间也全是那 银亮的色泽. 通晓军功章具有.发电功能“的干部. 会常常故意制造兵们和军功章约会的机会. 新兵到连队,搞一次英模报告会是固定节 目。在连队.类似的报告会…     

到二郎镇听酒的故事

好一个二郎滩,四面都是山. 天天背盐巴,顿顿菜汤淡. 古蔺是贫困县,幸好出酒,而且出好酒. 世事都是公平的.上帝关上一扇门,就会打开一扇窗.上苍加给你辛劳的生活,又赐予你酒. 一进二郎镇,一股浓郁的酒香扑鼻而来,事实上,沿途总有一阵阵的酒香飘进车窗. 从成都出发,汽车颠簸8小时,到了泸州市古蔺县二郎镇.崇山峻岭之中,现出一方人居.不由感慨蜀道之难、川民之苦.     

R.M.S系列丛书

为推动我国装备研制中可靠性、维修性和保障性(R.M.S)工作的开展,国防科工委军用标准化中心近几年组织翻译、编写了一系列很有参考价值的图书.这些图书包括;《R.M.S译文选》十二册,《R.M.S标准宣贯教材》九册,《R.M.S译丛》七册.另外还有一些与R.M.S有关的参考书,共有三十余册.是参与装备论证、设计、生产、监造、使用和维修工作的广大科技工作者开展可靠性、维修性、保障性等工作必备的参考资料,是工程技术院校的大中专学生和研究生的参考书与教材,是装备研制单位、科研单位的资料室和工程技术院校的图书馆必藏的图书.装甲兵工程学院参与了部分图书的翻译、编写、出版工作.     

心理测试

左脑右脑风格不同,测你用脑的风格因为用脑的不同,所以在风格上也会有很大的不同,让我们一起做个智商测试,看看你的左脑和右脑风格都是如何。1.对于发型,你会:A.尝试各种造型B.有时会试着改变C.几乎从不改变2.如果急需决断的时候,你会:A.凭直觉决定B.小事当机立断,大事认真思考C.左思右想,难以决断3.正在制订旅行计划,你会:A.渴望冒险,不怕危险B.一般不会冒险,但也会根据周围的意见,做适当改变C.经过了曾经的失败,要慎重制     

1989年我校在国际会议和国外刊物上发表的学术论文

1.一系.范子杰研究生,刘瑞岩副教授,季南教授.Model Parameter Estimationof A Large Missile Form Multi—shaker Random Excitation Test.TheInternational Model Analysis Conference(1989.2 U.S.A).2.一系.刘瑞岩副教授,季南教授,余少华研究生.Dynamic Optimization ofMachine Tool Structures.IST International Machinery Monitoring andDiagnostic Conference(1989.9.U.S.A).3.一系.洪志泉副教授,汤亦兵研究生.A Semi-analytical Calculation forDynamic Response of Underground Composite Structure Under Blast Loa-ding.Second International Conference on Development and Design with     

人生之中的22颗定时炸弹

下面的迹象标志着压力,你如果在22项中占有7项以上的话,那么你的压力就太大了。 1.双手冰凉2.经常眨眼——眼睛疲劳3.经常头痛4.高血压5.呼吸很浅或不均匀6.容易急躁或发怒7.坐下时膝盖紧张8.食欲时好时坏9.幽默感减少10.对性不感兴趣11.失眠12.睡眠过度13.胃不舒服14.思考吃力15.大量饮酒16.过度吸烟17.常使用镇静剂18.心情紧张19.紧咬牙齿20.忧虑21.面对挑战有准备不充分的感觉22.常嗑手指 下面有一些减轻压力的方法     

蕴涵深刻哲理的座右铭:“耐得寂寞”

著名作家姚雪垠有一则座右铭:耐得寂寞,勤学苦练.他还对这一座右铭作了耐人寻味的注脚:“我们有许多研究学术的,搞创作的,吃亏在不能耐得寂寞,总是怕别人忘记了他.由于耐不得寂寞,就不能深入地做学问.不能勤学苦练.他不知道耐得寂寞,才能不寂寞.耐不得寂寞,偏偏寂寞.”这里.姚雪垠虽然讲的是研究学术和搞创作,然而,其中却蕴涵着深刻的哲理.     

服务器虚拟化技术在消防信息中心的应用

针对信息中心服务器数量增长过快引起的诸多问题,提出了基于Citrix XenServer虚拟软件构架虚拟服务器环境,并对原有服务器资源进行整合,将其应用到消防信息中心系统的服务器部署中。新方案明显的提高了服务器的利用率,并降低了硬件投资,有效地减少了运营和维护成本。     

Development of proxy relationships: a case study of the Lebanese Civil War

Proxy warfare is a consistent element in international warfare. However, it is unclear why proxy relationships form in cases where states have multiple options of groups to support. Existing research identifies the presence of transnational constituencies, shared interstate rivalries, and moderate relative strength of militant groups as highly influential on the development of a proxy relationship. This study examines the presence of these variables within the context of the Lebanese Civil War. The results of this demonstrate that each state places greater importance on some variables and ignores others when choosing a proxy. Additionally, this study further demonstrates the presence of new variables that are key to the development of proxy relationships.     

基于虚拟服务器的负载均衡技术研究与实现

Intemet业务量的激增和网络应用特殊化,都使得负载均衡成为迫切需求。Linux虚拟服务器按传输层连接对集群节点进行业务分配,能便捷而高效地实现负载均衡。对Linux虚拟服务器集群的结构与原理进行讨论,重点阐述了满足不同应用需要的4种负载均衡算法,并在Linux操作系统环境下构建了虚拟服务器集群,测试了负载响应、服务性能、调度器备份。结果表明,虚拟服务器集群技术较大幅度地提高了系统的综合性能。     

Optimal control of an M/G/1 queue with impatient priority customers

An optimal operating policy is characterized for the infinite‐horizon average‐cost case of a single server queueing control problem. The server may be turned on at arrival epochs or off at departure epochs. Two classes of customers, each of them arriving according to an independent Poisson processes, are considered. An arriving 1‐customer enters the system if the server is turned on upon his arrival, or if the server is on and idle. In the former case, the 1‐customer is selected for service ahead of those customers waiting in the system; otherwise he leaves the system immediately. 2‐Customers remain in the system until they complete their service requirements. Under a linear cost structure, this paper shows that a stationary optimal policy exists such that either (1) leaves the server on at all times, or (2) turns the server off when the system is empty. In the latter case, we show that the stationary optimal policy is a threshold strategy, this feature being commonplace in most of priority queueing systems and inventory models. However, the optimal policy in our model is determined by two thresholds instead of one. © 2001 John Wiley & Sons, Inc. Naval Research Logistics 48: 201–209, 2001     

Modeling and analysis of flexible queueing systems

We consider queueing systems with multiple classes of customers and heterogeneous servers where customers have the flexibility of being processed by more than one server and servers possess the capability of processing more than one customer class. We provide a unified framework for the modeling and analysis of these systems under arbitrary customer and server flexibility and for a rich set of control policies that includes customer/server‐specific priority schemes for server and customer selection. We use our models to generate several insights into the effect of system configuration and control policies. In particular, we examine the relationship between flexibility, control policies and throughput under varying assumptions for system parameters. © 2004 Wiley Periodicals, Inc. Naval Research Logistics, 2004     

‘What is in a Name?’: The Role of (Different) Identities in the Multiple Proxy Wars in Syria

Abstract

Post-uprisings Middle East politics is frequently described as a ‘regional cold war’ involving proxy warfare that emphasises the role of shared identities linking external and local actors. But does the ‘content’ of identities impact proxy war dynamics? This article considers the present ‘battle for Syria’, a local conflict that became a theatre for multiple proxy wars involving actors emphasising identities on various levels, most notably national, religious/ sect and ethnic. It suggests that identity content does matter, with global powers more reluctant than regional players to back groups identifying at sub-national level, while foreign non-state actors are enthusiastic backers of sub-national identity.     

Optimal control of noncollaborative servers in two‐stage tandem queueing systems

We consider two‐stage tandem queueing systems with dedicated servers in each station and a flexible server that is trained to serve both stations. We assume no arrivals, exponential service times, and linear holding costs for jobs present in the system. We study the optimal dynamic assignment of servers to jobs assuming a noncollaborative work discipline with idling and preemptions allowed. For larger holding costs in the first station, we show that (i) nonidling policies are optimal and (ii) if the flexible server is not faster than the dedicated servers, the optimal server allocation strategy has a threshold‐type structure. For all other cases, we provide numerical results that support the optimality of threshold‐type policies. Our numerical experiments also indicate that when the flexible server is faster than the dedicated server of the second station, the optimal policy may have counterintuitive properties, which is not the case when a collaborative service discipline is assumed. © 2014 Wiley Periodicals, Inc. Naval Research Logistics 61: 435–446, 2014     

Stochastic analysis of a single server retrial queue with general retrial times

Retrial queueing systems are widely used in teletraffic theory and computer and communication networks. Although there has been a rapid growth in the literature on retrial queueing systems, the research on retrial queues with nonexponential retrial times is very limited. This paper is concerned with the analytical treatment of an M/G/1 retrial queue with general retrial times. Our queueing model is different from most single server retrial queueing models in several respectives. First, customers who find the server busy are queued in the orbit in accordance with an FCFS (first‐come‐first‐served) discipline and only the customer at the head of the queue is allowed for access to the server. Besides, a retrial time begins (if applicable) only when the server completes a service rather upon a service attempt failure. We carry out an extensive analysis of the queue, including a necessary and sufficient condition for the system to be stable, the steady state distribution of the server state and the orbit length, the waiting time distribution, the busy period, and other related quantities. Finally, we study the joint distribution of the server state and the orbit length in non‐stationary regime. © 1999 John Wiley & Sons, Inc. Naval Research Logistics 46: 561–581, 1999     

基于Linux虚拟服务器的负载均衡技术探讨

Internet业务量的激增和网络应用特殊化都使得负载均衡成为迫切需求。如何实现网络服务器负载均衡是一个急待解决的新课题。而LVS是一个具有良好的扩展性、高可靠性、高性能、高可用性的基于Linux系统的服务器集群,利用它可以较好解决这一问题。针对Linux虚拟服务器集群的负载均衡技术,探讨了其体系结构、工作方式、负载均衡算法,并以一简单的应用实例介绍了其具体实现。这样可以在很大程度上减轻网络的负载,提高网络的效率,是未来网络服务器技术的主要发展方向之一。     

On a single-server queue with state-dependent service

This paper discusses a class of queueing models in which the service time of a customer al a single server facility is dependent on the queue size at the onset of its service. The Laplace transform for the wait in queue distribution is derived and the utilization of the server is given when the arrival is a homogeneous Poisson process.