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普适计算导引
jiangdm 2011-11-5 10:33
目录 1 普适计算的重定位与探讨 authors: 於志文 周兴社 关键词: 普适计算 Mark Weiser 普适计算发展历程 第一阶段(1991~1998年):提出普适计算,追求“以人为中心、无处不在而又不可见”的计算 第二阶段(1999~2004年): WSN 第三阶段(2005~2010年):普适计算的研究趋于细化,多学科交叉融合 普适计算三大顶级学术会议,即UbiComp、PERVASIVE和PerCom 期刊:IEEE Pervasive Computing 个人点评: 从文中并没有理解 Pervasing computing 与 WSN的区别 普适计算的重定位与探讨.pdf 物联网对于计算科学的机遇与挑战.doc
个人分类: Network|0 个评论
review: 基于信任和服务预测的无线接入服务博弈控制方案
jiangdm 2011-10-27 09:10
review:  基于信任和服务预测的无线接入服务博弈控制方案
基于信任和服务预测的无线接入服务博弈控制方案 桂劲松   吴 敏 计算机研究与发展 2012 摘 要  自私的移动节点不仅不会无偿为其他节点转发分组,而且有多占系统资源的动机.为此,提出了一种移动节点与无线接入点之间的接入服务博弈控制方案.方案基于已有移动节点的行为信任等级、请求服务所需的资源要求,预测其未来一定属性组合条件下各个信任和请求服务等级的概率,并结合博弈分析给出了无线接入点接纳移动节点的概率和接纳控制的决策条件.一旦收到某移动节点的接入服务请求,并根据接纳概率,若无线接入点决定处理它,则基于贝叶斯网络模型预测其信任和请求服务等级 的未来值.基于预测值、接纳概率、移动节点的欺骗概率,无线接入点判断是否响应其接入服务请求.应用示例与仿真分析表明,方案对移动节点具有良好的激励作用和较强的服务响应能力,而且博弈消息代价比现有相关方案小. 关键词 无线接入服务;信任预测;服务预测;博弈;激励 1 相关工作与分析 激励机制: 基于信任度的方法、基于支付的方法、基于博弈的方法 -- 基于信任度方法 -- 基于支付的方法 -- 基于博弈的方法: Ad hoc VCG author idea: 信任度 + 博弈 2 基于信任和服务预测的博弈控制方案 2.1 方案概述 2.2 行为信任预测与请求服务等级预测 贝叶斯网络模型 移动节点请求服务的等级预测的贝叶斯基本网络模型可表示为如图3 3 应用示例与仿真分析 4 结论 基于信任和服务预测的无线接入服务博弈控制方案.pdf
个人分类: CHI|0 个评论
DNA计算
jiangdm 2011-10-19 23:43
从计算角度看DNA,我认为是高估了DNA的能力,现在研究整体尺度(大尺度)生物体基本了解;对于小尺度,如基因、DNA,现在正在深入。但是中尺度成为问题的瓶颈,因为它起着承上启下的作用 DNA自组装技术的研究进展及难点.pdf DNA计算的基本代数原理(一).pdf DNA计算机原理进展及难点3.pdf DNA计算机原理进展及难点V.pdf 经典DNA计算模型2.pdf 经典DNA计算模型I 位序列计算模型.pdf DNA计算机原理进展及难点 V 分子的固定技.pdf
个人分类: AI & ML|2 次阅读|0 个评论
review: 自主计算概念模型与实现方法
jiangdm 2011-10-8 11:46
review: 自主计算概念模型与实现方法
自主计算概念模型与实现方法 廖备水, 李石坚, 姚远, 高济 软件学报 ,2008 摘 要: 自主计算是一个新兴的热点研究领域,旨在通过“技术管理技术”的手段隐藏系统管理复杂性,建立用户可指导的、状态觉察的和自适应的计算机系统.目前,自主计算的研究仍处于起步阶段,尚缺乏系统而成熟的理论体系.在阐明自主计算概念的基础上,提出一个自主计算概念模型.该模型刻画了自主元素和自主计算系统的基本工作机制和原理.以该模型为依据,概括性地提出了两类分别 基于知识模型和数学模型的自主计算系统 ,分析它们的优点和不足.最后,给出了自主计算研究展望. 关键词: 自主计算;策略;Agent;Web服务;控制理论 信息系统: 大规模、开放、异构、动态 1 自主计算的定义和概念模型 1.1 自主计算的概念和定义 自主计算(autonomic computing):自配置、自优化、自修复和自保护 2001 IBM :在参照自主神经系统的自我调节机制,以现有的理论和技术(包括面向服务的计算、自适应控制理论、优化理论、基于策略的管理、多主体技术等)为基础构建自主计算系统,使得信息系统在“整体上(holistic)”实现自我管理 自主神经系统: (1-) 自主性: (2-) 状态觉察性: (3-) 自稳态性(homeostasis): 1.2 自主计算概念模型 自主计算系统(autonomic computing systems,ACS) 1.2.1 自主元素 1.2.2 自主计算系统 自主管理者工作机制:    一般来说,AM的基本工作机制可表示为如图2所示的情况(图中PA,PG和PU分别表示动作策略、目标策略和效用函数策略   包含 4个主要步骤 :   ① 自我觉察/上下文觉察;   ② 基于策略的决策;   ③ 目标导向的规划(可选);   ④ 动作/规划执行 自主计算系统  VS multi-agent systems,MAS ACS特点: (1) 需要接受动态的IT策略的指导; (2) 重点研究如何利用个体自主元素的自我管理功能来实现整个系统的动态平衡  从 自主元素组织结构、AM协作关系形成和AM行为编排 等3个主要方面讨论    编排方法:    i)基于动态规划的方法    ii)基于工作流的方法    iii)基于自组织涌现理论的方法 2 两类主要的自主计算实现方法 自主计算系统实现:  1)知识模型方法     Agent技术、Web服务和语义  2)数学模型方法     自适应控制理论,效用函数 2.1.1 方法1:Web服务+动作策略+反应Agent 2.1.2 方法2:语义Web服务+目标策略+慎思Agent 主要技术挑战 : (1) 状态觉察和问题确定:  (a) 在状态信息的获取和过滤方面;  (b) 在问题确定方面,涉及到如何产生和维护症状库、如何判定和追溯处于动态环境中的由多个交互元素引起的问题根源以及如何产生自动关联规则等 (2) 策略的细化和冲突处理:  (a) 从高层IT策略到底层可实施策略的映射和细化是构建该类自主系统的关键环节, 其技术难题是 如何自动地对策略进行细化,并分析和验证细化结果的一致性和完整性;  (b) 策略在实施的过程中,可能引起逻辑上或资源上的冲突,因此,策略冲突处理和自适应成为该类AM决策的主要问题. 发展趋势 (1) 知识模型方法和数学模型方法相结合: (2) 标准化和语义相结合: (3) 硬计算和软计算相结合 个人点评: 很遗憾!一般一看到是IBM提出来的,我就认为很水。不是说IBM技术不行,而是说IBM 忽悠概念 能力超强!两三年造个概念,一次俩次还好,太多了就令人烦。我看过文章后,不知道 自主计算 与 Multi-Agent System 有什么本质区别?学习Agent时可参考一下 自主计算概念模型与实现方法.pdf
个人分类: web service|3396 次阅读|0 个评论
review: 安全协议的设计与逻辑分析
jiangdm 2011-9-19 22:56
review: 安全协议的设计与逻辑分析
安全协议的设计与逻辑分析 卿斯汉 2003 Journal of Software 软 件 学 报 Vol.14, No.7 摘 要: 随着网络应用的迅速发展,网络安全的问题日益重要.研究下述课题:安全协议的设计原则;安全协议设计中形式化方法的应用;各种形式化分析方法,特别是逻辑分析方法的特点.另外,还探讨了串空间模型在逻辑分析中的应用以及串空间模型指导安全协议形式化设计的可能性. 关键词: 安全协议;设计;逻辑分析;BAN类逻辑;串空间 密码学 - 安全协议 安全协议: 实体之间认证、实体之间安全地分配密钥或其他各种秘密、确认发送和接收消息的非否认性 安全协议的形式化分析: -- 基于知识与信念推理的模态逻辑方法 -- 基于通信状态机模型的研究方法 -- 基于知识推理的代数方法 -- 基于顺序通信进程的CSP方法 -- 串空间模型 the organization of this paper: 1) 第1节讨论基于知识与信念推理的模态逻辑方法,对BAN逻辑及其扩展: GNY逻辑 、AT逻辑 、VO逻辑 进行详尽的研究,比较它们的特点和优缺点. 2) 第2节讨论BAN类逻辑中:SVO逻辑 ,并研究安全协议的逻辑分析方法和串空间模型 相结合的问题. 3) 第3节讨论安全协议设计原则.然后,通过串空间模型的实例,说明形式化方法如何指导安全协议的正确设计. 4) 第4节是简短的结论,并讨论今后研究的若干方向. 1 安全协议的形式化分析方法 1.1 基于知识与信念推理的模态逻辑方法 1.2 BAN逻辑 BAN逻辑 2 BAN类逻辑分析方法与串空间模型 2.1 SVO逻辑 2.2 串空间模型与BAN类逻辑 模型论语义 串空间模型语义 3 安全协议的设计 3.1 安全协议设计的原则 3.2 应用形式化方法指导安全协议设计 4 结 论 安全协议的设计与逻辑分析.pdf
个人分类: Network|3856 次阅读|0 个评论
韩燕波 蔡维德
jiangdm 2011-8-30 15:49
Contents 1 韩燕波 互联网计算原理与实践 物联网与云计算 面向服务的计算 2 蔡维德 浅谈深析面向服务的软件工程 高可伸缩、动态重构 ——服务计算对软件系统测试的两个挑战 1 韩燕波 韩燕波《互联网计算原理与实践 --探索网格、云和Web X.0背后本质问题和关键技术》 姊妹书:《面向服务的计算 --- 原理和应用》,喻坚,韩燕波,2006 书是一本新书,原来做过Beamer,今天(2011.8.30)想进一步修改Beamer,但本书存在问题是我放弃。 问题: 1)书中各知识点没有有机融合,内容偏散,偏杂。 2)本书引用过多,更像是知识的堆砌, 思考: 1)下一步精读 Tanenbaum A S. Distributed Systems: Principles and Paradigms 2) 关注点 Google AppEngine 和Google三驾马车: BigTable 数据库, GFS (Google文件系统)和 MapReduce (Google分布式 编程模式) Eucalyptus 开源云计算平台 (Amazon EC2 开源实现) Dynamo (key-value分布式数据存储和管理系统, Amazon) Cassandra 开源key-value 分布式数据存储和管理系统,借鉴了Amazon Dynamo 和 Google BigTable Hadoop MapReduce 开源实现 Distibuted Hash Table beamer_互联网计算原理与实践.pdf beamer_互联网计算原理与实践.tex 互联网计算原理与实践.ppt 物联网与云计算 计算机学会通讯 , 2010 韩燕波 赵卓峰 王桂玲 刘 晨 关键词: 物联网 云计算 应用广泛互联与跨域集成 个人点评: 与我思考相近,即云是物联网“后端”,见下图示意 但是,我感觉云计算和sensor Network如何无缝连接却没有很好的研究 物联网与云计算.pdf 面向服务的计算 (book) 喻坚 韩燕波 这本书是老板在复试前送给我看得,至今看得是懂非懂,文章是要造得,与老板申请下来的课题相关,250w,也与自己毕业西息息相关。但是我坚持认为:看文章是一回事,编程实践则是另一回事。 I hear, and I forget. I see, and I remember. I do, and I understand! 面向服务的计算- 原理和应用 喻坚.doc beamer_面向服务的计算_喻坚.tex 2 蔡维德 浅谈深析面向服务的软件工程 读书笔记 蔡维德 浅谈深析面向服务的软件工程.rar 高可伸缩、动态重构 ——服务计算对软件系统测试的两个挑战 白晓颖 蔡维德 宫云战 黄俊飞 CCF通讯 2010 关键词:高可伸缩 动态重构 服务计算 系统测试 1 前言 云计算平台: 多层次的资源共享模式 -- 基础设施即服务(Infrastructure as a Service,IaaS) -- 平台即服务(Platform as a Service,PaaS) -- 数据即服务(Data as a Service,DaaS) -- 软件即服务(Software as a Service,SaaS) SOA: 软件提供、软件使用和软件中介三方分离的体系架构 软件质量: 高可伸缩和动态重构 -- 高可伸缩性 -- 动态重构 2 可伸缩性和动态重构问题 2.1 可伸缩性 2.1.1 从性能提升到降低费用 2.1.2 系统可伸缩性 2.1.3 多租户问题 2.2 动态重构 3 软件系统测试探讨 3.1 若干基本特性 3.1.1 分而治之 3.1.2 协同性 3.2 关键技术 3.2.1 可测试性设计 3.2.2 基于多Agent的模拟技术 3.2.3 动态故障模型 4 结语 高可伸缩 动态重构.pdf
个人分类: CHI|1 次阅读|0 个评论
review: TOWARD NATURE-INSPIRED Computing
jiangdm 2011-8-17 21:08
contents 1 TOWARD NATURE-INSPIRED COMPUTING 2 丁永生《自然计算与网络智能》 《TOWARD NATURE-INSPIRED COMPUTING》 Jiming Liu and K.C. Tsui CACM 2006 Abstract: NIC-based systems utilize autonomous entities that self-organize to achieve the goals of systems modeling and problem solving 文献类型: 导论性文章 研究目标:Nature-inspired Computing 研究方法: 1, 作者提出 prototype for autonomous entities 2, 指出 autonomous entities 五个特性 比基尼: 难点 重点 疑点 个人点评: 与我思路中的 Immune Computing 相近,以后进一步阅读 文章不足之处: 作者其它文献脉络 相关重要文献 TOWARD NATURE-INSPIRED.pdf beamer_toward_nature-inspired_computing.tex beamer_toward_nature-inspired_computing.pdf 面向自治计算介绍.pdf 书评:丁永生《自然计算与网络智能》 自然计算(Nature-Inspired Computing)是从社会学、经济学或生物学启发,抽象构建其数学模型并设计计算模型及算法,例如进化计算、免疫计算等。在知识细分工和大融合的趋势下,自然计算已在多个领域得到应用,如多目标优化、智能控制及计量经济学等。 本书各章分别从免疫计算、生态学、经济系统、社会网络角度出发,研究Internet computing。但是个人以为此书标题写得吸引人,其中内容却如蜻蜓点水一般。可借鉴之处就是看看其部分参考文献:
个人分类: AI & ML|1 次阅读|0 个评论
review: A Formalisation of Adaptable Pervasive Flows
jiangdm 2011-8-9 09:33
《A Formalisation of Adaptable Pervasive Flows》, Antonio Bucchiarone, Alberto Lluch Lafuente, Annapaola Marconi, and Marco Pistore WS-FM 2009 Abstract. Adaptable Pervasive Flows is a novel workflow-based paradigm for the design and execution of pervasive applications, where dynamic workflows situated in the real world are able to modify their execution in order to adapt to changes in their environment. In this paper, we study a formalisation of such flows by means of a formal flow language. More precisely, we define APFoL (Adaptable Pervasive Flow Language) and formalise its textual notation by encoding it in Blite, a formalisation of WS-BPEL. The encoding in Blite equips the language with a formal semantics and enables the use of automated verification techniques. We illustrate the approach with an example of a Warehouse Case Study. 个人点评: 作者扩展WS-BPEL为APFoL,用Blite(process algebra)加以形式化,将应用于Prevasive computing,其扩展基点是:1) flexible; 2) adaptive A Formalisation of Adaptable Pervasive Flows.pdf beamer_Formalisation_Adaptable_Pervasive_Flows.pdf
个人分类: Formal method|1 次阅读|0 个评论
review: A Tool for Integrating Pervasive Services and Simula
jiangdm 2011-8-6 08:51
《A Tool for Integrating Pervasive Services and Simulating Their Composition》, Ehsan Ullah Warriach, Eirini Kaldeli, Jaap Bresser, Alexander Lazovik, and Marco Aiello ICSOC 2010, Abstract. As computation and services are pervading our working and living environments, it is important for researchers and developers to have tools to simulate and visualize possible executions of the services and their compositions. The major challenge for such tools is to integrate highly heterogeneous components and to provide a link with the physical environment. We extend our previous work on the RuG ViSi tool , in a number of ways: first, we provide a customizable and interactive middleware based on open standards (UPnP and OSGi) ; second, we allow any composition engine to guide the simulation and visualization (not only predefined compositions using BPEL) ; third, the interaction with simulated or physical devices is modular and bidirectional, i.e., a device can change the state of the simulation. In the demo, we use an AI planner to guide the simulation, a number of simulated UPnP devices, a real device running Java, and a two room apartment. The related video is available at http://www.youtube.com/watch?v=2w_UIwRqtBY . The EU Smart Homes for All (SM4All) project: goal: apply a Service Oriented Computing approach to the smart home 个人点评: 工程角度研究论文,用SOC增加理论水分 学术文章分两类: 工程类: 如google GFS,MapReduce等论文,始于解决问题,重视实用,强调集成。但从理论角度,并不太新,而是从数学,控制理论等多角度建模。换而言之,理论只是起抽象,提升文章理论的作用 学术类: 更多时将理论瞎套用在热点问题上,也就所谓的 “锤子理论 ”,不管行不行,先砸再说。不管理论是否适用,先出文章再说。 A Tool for Integrating Pervasive Services and Simulating Their Composition.pdf
个人分类: web service|2227 次阅读|0 个评论
review: A journey to highly dynamic, self-adaptive service
jiangdm 2011-6-6 20:08
综述 A journey to highly dynamic, self-adaptive service-based applications Abstract: Future software systems will operate in a highly dynamic world. Systems will need to operate correctly despite of unespected changes in factors such as environmental conditions, user requirements, technology, legal regulations, and market opportunities. They will have to operate in a constantly evolving environment that includes people, content, electronic devices, and legacy systems. They will thus need the ability to continuously adapt themselves in an automated manner to react to those changes. To realize dynamic, self-adaptive systems, the service concept has emerged as a suitable abstraction mechanism. Together with the concept of the service-oriented architecture (SOA), this led to the development of technologies, standards, and methods to build service-based applications by flexibly aggregating individual services. This article discusses how those concepts came to be by taking two complementary viewpoints. On the one hand, it evaluates the progress in software technologies and methodologies that led to the service concept and SOA. On the other hand, it discusses how the evolution of the requirements, and in particular business goals, influenced the progress towards highly dynamic self-adaptive systems. Finally, based on a discussion of the current state of the art, this article points out the possible future evolution of the field. Keywords: Service-oriented computing · Services · Adaptive systems ·Self-adaptation 文章: 1)a historical perspective 2)Current technology and methods for service-based applications 该部分围绕 (Figure 5)Layers and aspects relevant for service-based applications 3)Today’s technology and methods vs. application scenarios present two application scenarios: Federated organizations A pervasive computing scenario 4)Open issues and challenges 从以下六个方面讨论 Business process management Service composition and coordination Service infrastructure Analysis, design, and development Service quality definition, negotiation, and assurance Run-time adaptation Context beamer_journey_serivces.pdf A journey to highly dynamic, self-adaptive service-based applications.pdf
个人分类: web service|2690 次阅读|0 个评论
A quick introduction to membrane computing
jiangdm 2011-5-4 15:38
《A quick introduction to membrane computing》,The Journal of Logic and Algebraic Programming,Elsevier,2010 A B S T R A C T: Membrane computing is a branch of natural computing inspired from the architecture and the functioning of biological cells. The obtained computing models are distributed parallel devices, called P systems, processing multisets of objects in the compartments defined by hierarchical or more general arrangements of membranes. Many classes of P systems were investigated – mainly fromthe point of viewofcomputing power andcomputing efficiency; also, a series of applications (especially in modeling biological processes) were reported. This note is a short and informal introduction to this research area, introducing a few basic notions, research topics, types of results, and pointing out to some relevant references. review: membrane computing --- a branch of natural computing which abstracts computing models from the architecture and the functioning of living cells, as well as from the organization of cells in tissues, organs (brain included) or other higher order structures such as colonies of cells (e.g., of bacteria). The main ingredients of a P systemare (i) the membrane structure, delimiting compartments where (ii) multisets of objects evolve according to (iii) (reaction) rules of a biochemical inspiration. the main issues studied concern the computing power (in comparison with standard models from computability theory, especially Turing machines/Chomsky grammars and their restrictions) the computing efficiency (the possibility of using parallelism for solving computationally hard problems in a feasible time). there are three main types of P systems: (i) cell-like P systems, (ii) tissue-like P systems, and (iii) neural-like P systems. web site: http://ppage.psystems.eu A quick introduction to membrane computing.pdf Membrane computing and programming.pdf 补充中文文献:《自然计算的新分支———膜计算》,计算机学报,2010.2 摘 要  作为自然计算的新分支,膜计算是当前计算机科学、数学、生物学和人工智能等多学科交叉的研究热点. 概述膜计算的最新动态,以一个简单膜系统为例介绍膜计算的基本概念和基本原理,从细胞型、组织型和神经型三类膜系统以及它们的计算能力和计算效率方面介绍膜计算理论研究进展,通过概括膜计算国内外应用研究成果讨论其应用前景和方向,并从软硬件发展历程分析膜系统软硬实现研究现状.最后给出有关膜计算研究的重要网络资源、热点研究领域和重点关注的问题 自然计算的新分支—膜计算.pdf
个人分类: AI & ML|3193 次阅读|0 个评论
[转载]Cloud computing
zuojun 2010-11-7 04:32
From wikipedia: Criticism of the term This article's Criticism or Controversy section(s) may mean the article does not present a neutral point of view of the subject . It may be better to integrate the material in those sections into the article as a whole. (March 2010) During a video interview, Forrester Research VP Frank Gillett expresses criticism about the nature of and motivations behind the push for cloud computing. He describes what he calls cloud washing in the industry whereby companies relabel their products as cloud computing resulting in a lot of marketing innovation on top of real innovation. The result is a lot of overblown hype surrounding cloud computing. Gillett sees cloud computing as revolutionary in the long term but over-hyped and misunderstood in the short term, representing more of a gradual shift in our thinking about computer systems and not a sudden transformational change. Larry Ellison , CEO of Oracle Corporation has stated that cloud computing has been defined as everything that we already do and that it will have no effect except to change the wording on some of our ads. Oracle Corporation has since launched a cloud computing center and worldwide tour. Forrester Research Principal Analyst John Rymer dismisses Ellison's remarks by stating that his comments are complete nonsense and he knows it. Richard Stallman said that cloud computing was simply a trap aimed at forcing more people to buy into locked, proprietary systems that would cost them more and more over time. It's stupidity. It's worse than stupidity: it's a marketing hype campaign, he told The Guardian. Somebody is saying this is inevitable and whenever you hear somebody saying that, it's very likely to be a set of businesses campaigning to make it true.
个人分类: From the U.S.|2196 次阅读|0 个评论
The cloud issue you really can't ignore
feicheng 2010-9-28 09:28
Maybe it's time to rethink the cloud. Yeah, I know -- at this point, most IT shops haven't thought through the cloud the first time. But Microsoft's recent troubles keeping its cloud services available to users shine a harsh light on the issue of cloud availability and reliability. Trouble is, those are the wrong things to be thinking about. Sure, it sounds bad when a vendor as big as Microsoft can't keep its cloud network running. It's not comforting to know that Google , Amazon , Rackspace and other cloud providers have had outages too. So has software-as-a-service king Salesforce.com . Look, the cloud involves too many miles of somebody else's wire between users and their applications for networking hiccups to be eliminated completely. But cloud availability will get better. It's a problem that cloud vendors know about -- and know they have to solve. Let's think about a much bigger problem: The cloud is a good place to move a stand-alone virtualized server (or it will be, once vendors get their availability act together). But how much of your current data center falls into that category? Don't answer yet. First, think about all your virtual-server applications that don't really stand alone. They talk to shared data stores or other applications. Their performance literally depends on how far data has to travel. Inside your data center, that's trivial. But up in the cloud, millions of round trips could be necessary between an application in the cloud and data in your IT shop. Even at light speed, that takes time. Maybe you're thinking you could send the whole group of applications that use the same data stores up to the cloud. No more round trips, right? But one key principle of cloud computing is that you never know exactly where an app will run. With some providers, apps and data could end up communicating between New York, Silicon Valley, Seattle and Mumbai -- and total network latency could go from a problem to a catastrophe. You can solve those problems. But that might mean redesigning how those applications work, how they communicate and how they interact. Now think about this: That's the pretty part of your data center. Then there's the ugly stuff, the part we don't like to think about. Apps that, say, scrape some mainframe screens, combine their contents with data from specialized industry-vertical software, then run the result through legacy business logic that no one has touched in years for fear of breaking a critical piece of some department's business process. Our data centers are littered with that kind of cruft, accumulated over decades as we've moved from one IT paradigm to the next. There's never time or money to fix it because, kludgy as it is, it still does what users need, and untangling it will be all IT cost with no business-side benefit. But without that untangling, it will never work in the cloud. So here's something worth thinking about: How much of what's in your data center is ready for the cloud? How much of it will have to be reconfigured, rebuilt or re-architected before you'll be able to move it up to the cloud? How much will never be cloudworthy? And do you really think you'll have thought that all through before Microsoft learns how to run a network? Read more about Cloud Computing in Computerworld's Cloud Computing Topic Center. 来自: Computerworld
个人分类: 一般认识|1900 次阅读|0 个评论
P 不等于 NP, HP研究员Vinay Deolalikar的工作
qizhwei 2010-8-10 17:34
HP研究员VinayDeolalikar也许会拿走Clay研究所的大奖,8月6号的论文打破了计算机理论界的最大的难题,P=NP?一系列的证明都是以"ifP=NPthen"开头,以后也许不用再写了,这个证明将会产生新的结果,搞理论的同学们有一堆事情可以做了.如证明成功,见证了一个伟大的数学证明,属于人类的思想洞察力和VinayDeolalikar本人的原创力! http://rjlipton.wordpress.com/2010/08/08/a-proof-that-p-is-not-equal-to-np/ AseriousproofthatclaimstohaveresolvedtheP=NPquestion. VinayDeolalikarisaPrincipalResearchScientistatHPLabswhohasdoneimportantresearchinvariousareasofnetworks.Healsohasworkedoncomplexitytheory,includingpreviousworkoninfiniteversionsoftheP=NPquestion.HehasjustclaimedthathehasaproofthatPisnotequaltoNP.That’sright:.Noinfiniteversion.Therealdeal. TodayIwilltalkabouthispaper.SofarIhaveonlyhadachancetoglanceatthepaper;Iwilllookatitmorecarefullyinthefuture.Idonotknowwhattothinkrightnow,butIamcertainlyhopeful. 论文全文: http://www.hpl.hp.com/personal/Vinay_Deolalikar/Papers/pnp12pt.pdf
个人分类: 学术探讨|7551 次阅读|0 个评论
Grid computing of spatial statistics:using the TeraGrid for Gi*(d) analysis
guodanhuai 2010-3-24 15:56
Wang, S., M. K. Cowles, et al. (2008). Grid computing of spatial statistics: using the TeraGrid forGi* analysis. Concurrency and Computation: Practice and Experience 20(14): 1697-1720. The massive quantities of geographic information that are collected by modern sensing technologies are difficult to use and understand without data reduction methods that summarize distributions and report salient trends. Statistical analyses, therefore, are increasingly being used to analyze large geographic data sets over a broad spectrum of spatial and temporal scales. Computational Grids coordinate the use of distributed computational resources to form a large virtual supercomputer that can be applied to solve computationally intensive problems in science, engineering, and commerce. This paper presents a solution to computing a spatial statistic, Gi*(d) using Grids. Our approach is based on a quadtree-based domain decomposition that uses task-scheduling algorithms based on GridShell and Condor. Computational experiments carried out on the TeraGrid were designed to evaluate the performance of solution processes. The Grid-based approach to computing values for Gi*(d) shows improved performance over the sequential algorithm while also solving larger problem sizes. The solution demonstrated not only advances knowledge about the application of the Grid in spatial statistics applications but also provides insights into the design of Grid middleware for other computationally intensive applications. Copyright 2008 John Wiley Sons, Ltd.
个人分类: GIsystem & GIscience|3840 次阅读|0 个评论
云计算的定义
Jiyi 2009-7-28 21:20
维基百科(Wikipedia.org)对云计算的定义: 云计算是分布式计算技术的一种,其最基本的概念,是通过网络将庞大的计算处理程序自动分拆成无数个较小的子程序,再交由多部服务器所组成的庞大系统进行搜寻和计算分析,最后将处理结果回传给用户.通过这项技术,网络服务提供者可以在数秒内,处理数以千万计甚至亿计的信息,达到和超级计算机同样强大效能的网络服务. 加州大学伯克利分校(University of California at Berkeley)的Michael Armbrust等对云计算的定义: 云计算包括互联网上各种服务形式的应用以及这些服务所依托数据中心的软硬件设施,这些应用服务一直被称作软件即服务(SaaS),而数据中心的软硬件设施就是所谓的云, 云计算就是SaaS和效用计算.云分为公共云(Public Cloud)和私有云(Private Cloud). 云计算(Cloud computing)是一种基于互联网的超级计算模式,其原理非常类似于网格计算.它是把存储在大量分布式计算机产品中的大量数据和处理器资源整合在一起协同工作.作为一种新兴的共享基础架构的方法,它可以将巨大的系统池连接在一起以提供各种IT 服务.这使得企业能够将资源切换到需要的应用上,根据需求访问计算机和存储系统. 云安全联盟(Cloud Security Alliance, CSA)的研究报告提出的SPI模型(SPI Model)把云计算的服务形式分为基础架构即服务(Infrastructure as a Service,IaaS),平台即服务(Platform as a Service,PaaS)和软件即服务(Software as a Service,SaaS)三大类。开放云宣言组织(Open Cloud Manifesto)则根据研究的需要把云计算细分成终端用户―云、企业―云―终端用户、企业―云(综合)、企业―云―企业、企业―云(便携式)、私有(内部)云等6种模式。 作为网络时代的新计算形式,云计算是以数据、用户和服务为三大中心为导向的.在功能方面,真正的云计算平台应该能具备以下三方面的功能特性. ⑴提供资源――包括计算、存储及网络资源,需要服务提供者架设出规模巨大的全球化的数据库及存储中心,能够实现海量的存储、出色的安全性和高度的隐私性和可靠性.此外,它还应是高效的、低价的、节省能源的. ⑵提供动态的数据服务――包括原始数据、半结构化数据和经过处理的结构化数据,一个优秀的云计算架构一定要有提供大规模数据存储、分享、管理、挖掘、搜索、分析和服务的智能. ⑶提供云计算平台――包括软件开发API、环境和工具.云计算需要真正形成一个有生命力、有黏性、可持续发展的生态系统.
个人分类: 未分类|7358 次阅读|0 个评论
计算科技哲学---伦理学问题研究资料
huangfuqiang 2008-11-7 15:50
Social and ethical issues in computer science social: issues about computers in society social, political and legal ethical: making decisions about what is right Social informatics Rob Kling : . . . is the interdisciplinary study of the design, uses and consequences of information technologies that takes into account their interaction with institutional and cultural contexts. What is Social Informatics and Why Does it Matter? on Ethical Issues in Computing Social and ethical issues in computer science
个人分类: 信息&工程&逻辑哲学|3334 次阅读|0 个评论

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