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A revisit to MacKay algorithm and its application to deep network compression

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Frontiers of Computer Science 2020年第4期14卷 39-54页

作者： Chune li Yongyi MAO Richong ZHANG jinpeng huai School of Computer Science and Engineering Beihang UniversityBeijing100191China School of Electrical Engineering and Computer Science University of OttawaOttawaK1N6N5Canada

An iterative procedure introduced in MacKay’s evidence framework is often used for estimating the hyperparameter in empirical *** with the use of a particular form of prior,the estimation of the hyperparameter reduces to an automatic relevance determination model,which provides a soft way of pruning model *** the effectiveness of this estimation procedure,it has stayed primarily as a heuristic to date and its application to deep neural network has not yet been *** paper formally investigates the mathematical nature of this procedure and justifies it as a well-principled algorithm framework,which we call the MacKay *** an application,we demonstrate its use in deep neural networks,which have typically complicated structure with millions of parameters and can be pruned to reduce the memory requirement and boost computational *** experiments,we adopt MacKay algorithm to prune the parameters of both simple networks such as LeNet,deep convolution VGG-like networks,and residual netowrks for large image classification *** results show that the algorithm can compress neural networks to a high level of sparsity with little loss of prediction accuracy,which is comparable with the state-of-the-art.

关键词： deep learning MacKay algorithm model compression neural network

Big graph search： challenges and techniques

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Frontiers of Computer Science 2016年第3期10卷 387-398页

作者： Shuai MA Jia li Chunming HU Xuelian liN jinpeng huai State Key Laboratory of Software Development Environment School of Computer Science and Engineering Beihang University Beijing 100191 China

On one hand, compared with traditional rela- tional and XML models, graphs have more expressive power and are widely used today. On the other hand, various ap- plications of social computing trigger the pressing need of a new search paradigm. In this article, we argue that big graph search is the one filling this gap. We first introduce the ap- plication of graph search in various scenarios. We then for- malize the graph search problem, and give an analysis of graph search from an evolutionary point of view, followed by the evidences from both the industry and academia. After that, we analyze the difficulties and challenges of big graph search. Finally, we present three classes of techniques to- wards big graph search： query techniques, data techniques and distributed computing techniques.

关键词： graph search big data query techniques data techniques distributed computing

CROWN:A service grid middleware with trust management mechanism

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Science in China(Series F) 2006年第6期49卷 731-758页

作者： huai jinpeng HU Chunming li Jianxin SUN Hailong WO Tianyu School of Computer Science & Engineering Beihang University Beijing 100083 China

Based on a proposed Web service-based grid architecture, a service grid middleware system called CROWN is designed in this paper. As the two kernel points of the middleware, the overlay-based distributed grid resource management mechanism is proposed, and the policy-based distributed access control mechanism with the capability of automatic negotiation of the access control policy and trust management and negotiation is also discussed in this paper. Experience of CROWN testbed deployment and application development shows that the middleware can support the typical scenarios such as computing-intensive applications, data-intensive applications and mass information processing applications.

关键词： Grid computing service grid middleware resource management distributed access control trust management CROWN.

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多自治域协同环境中群组通信的安全访问控制

计算机研究与发展 2005年第9期42卷 1558-1563页

作者：张煜张文燚李先贤怀进鹏北京航空航天大学计算机学院北京100083

支持多自治域协作的安全通信环境是大规模分布式应用的基础,群通信由于高效、可伸缩等特点,成为这种协作环境的一种基本通信方式.然而,由于没有集中的控制中心,实体分别隶属于异构的自治域且动态变化,引发了大量新的安全访问控制问题.... 详细信息

支持多自治域协作的安全通信环境是大规模分布式应用的基础,群通信由于高效、可伸缩等特点,成为这种协作环境的一种基本通信方式.然而,由于没有集中的控制中心,实体分别隶属于异构的自治域且动态变化,引发了大量新的安全访问控制问题.针对多域协作的异构性和动态性特点,提出一套基于角色的分布式信任管理的解决方案,重点解决了动态联合授权以及基于属性的委托授权.在此基础上建立了一套较完整的安全通信体系,包括安全策略的协商、信任证的颁发、信任证与安全策略的一致性验证以及用户访问权限论证等.它为多域协作环境的群通信提供了更加灵活、可靠、安全的访问控制模式.

关键词：群通信信任管理访问控制联合授权

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安全协议的攻击分类及其安全性评估

计算机研究与发展 2005年第7期42卷 1100-1107页

作者：卓继亮李先贤李建欣怀进鹏北京航空航天大学计算机学院北京100083

对安全协议的安全性进行全面评估是十分重要的,但难度非常大.目前大量的研究工作主要集中于分析开放网络环境下安全协议的一些特定安全属性,例如,秘密性和认证性等.为了更全面地评估安全协议的安全防护能力,从攻击者的能力和攻击后果两... 详细信息

对安全协议的安全性进行全面评估是十分重要的,但难度非常大.目前大量的研究工作主要集中于分析开放网络环境下安全协议的一些特定安全属性,例如,秘密性和认证性等.为了更全面地评估安全协议的安全防护能力,从攻击者的能力和攻击后果两个角度,提出一种新的安全协议攻击分类,并分析了不同攻击类型的特点与机理.在此基础上,探讨了安全协议的一种安全性评估框架,有助于更客观地评价安全协议的实际安全防护能力和设计新的协议.

关键词：安全协议攻击分类安全性评估形式化方法

AutoSyn:A new approach to automated synthesis of composite web services with correctness guarantee

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Science in China(Series F) 2009年第9期52卷 1534-1549页

作者： huai jinpeng1,2,DENG Ting1,2,li xianxian1,2,DU ZongXia1,2 & GUO HuiPeng1,2 1 National Laboratory of Software Development Environment,Beihang University,Beijing 100191,China 2 School of Computer Science & Engineering,Beihang University,Beijing 100191,China National Laboratory of Software Development Environment Beihang University Beijing 100191 China School of Computer Science & Engineering Beihang University Beijing 100191 China

How to compose existing web services automatically and to guarantee the correctness of the design （e.g. freeness of deadlock and unspecified reception, and temporal constraints） is an important and challenging problem in web services. Most existing approaches require a detailed specification of the desired behaviors of a composite service beforehand and then perform certain formal verification to guarantee the correctness of the design, which makes the composition process both complex and time-consuming. In this paper, we propose a novel approach, referred to as AutoSyn to compose web services, where the correctness is guaranteed in the synthesis process. For a given set of services, a composite service is automatically constructed based on L＊ algorithm, which guarantees that the composite service is the most general way of coordinating services so that the correctness is ensured. We show the soundness and completeness of our solution and give a set of optimization techniques for reducing the time consumption. We have implemented a prototype system of AutoSyn and evaluated the effectiveness and efficiency of AutoSyn through an experimental study.

关键词： business protocol synthesis composite service correctness constraints L* algorithm

Reliability-aware automatic composition approach for web services

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Science China(Information Sciences) 2012年第4期55卷 921-937页

作者： li Mu 1,2,li Bo 1,2 & huai jinpeng 1,2 1 State Key Laboratory of Software Development Environment,Beihang University,Beijing 100191,China 2 School of Computer Science and Engineering,Beihang University,Beijing 100191,China 1. State Key Laboratory of Software Development Environment Beihang University Beijing 100191 China2. School of Computer Science and Engineering Beihang University Beijing 100191 China

In this paper,we study the reliability-aware synthesis problem for composing available services automatically and guaranteeing that the composed result satisfies the specification,such as temporal constraints of functionality and reliability,centered on a synthesis model for mediator of web services composition (CSM).This approach focuses on handling attributes and state relations,and permitting users and services to operate over them,i.e.,read /write their data values and compare them according to a dense state *** show that the reliability-aware synthesis problem for the specification is EXPTIME-complete and we give an exponential-time algorithm (CSM-NSA) which for a given formula ψ and a synthesis model,synthesizes available services in the library satisfying ψ over the synthesis model (if they exist) or responds with "not satisfiable" (otherwise).The specification ψ is a fragment of PCTL (probabilistic computation tree logic),obtained from "ordinary" CTL (computation tree logic) by replacing the EX,AX,EU and AU operation with their quantitative counterparts X >p,X =1,U >p,and U =1,*** opposed to NSA,we provide a more effective algorithm to replace the NSA algorithm called CSM-HSA (heuristic synthesis algorithm).Though HSA is an incomplete algorithm,the answer is *** experiments show that the HSA algorithm solves the problem of reliability-aware service synthesis effectively and efficiently.

关键词： reliability web services synthesis problem synthesis model heuristic algorithm

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网格计算环境中的安全信任协商系统

北京航空航天大学学报 2006年第3期32卷 347-351页

作者：张荣清李建欣怀进鹏北京航空航天大学计算机学院北京100083

网格技术促进了广域网络环境下的资源共享和协同工作.然而,在网格环境中,服务的提供方和请求方往往位于不同的安全域,如何为位于不同安全区域的陌生主体间动态地建立信任关系成为一项应用难题.基于信任管理基础设施,通过协作主体间信任... 详细信息

网格技术促进了广域网络环境下的资源共享和协同工作.然而,在网格环境中,服务的提供方和请求方往往位于不同的安全域,如何为位于不同安全区域的陌生主体间动态地建立信任关系成为一项应用难题.基于信任管理基础设施,通过协作主体间信任证、访问控制策略的交互披露逐渐为各方建立信任关系,设计并实现了一个保护协商方隐私信息的安全信任协商系统.该系统采用一种基于属性的委托授权信任证、访问控制策略及一致性验证算法,实现策略的动态调整,从而生成满足访问控制策略的所有最小可满足信任证集,能够使理论上存在的信任关系得以自动建立.通过在CROWN平台中的应用,显示该系统能够满足网格应用中信任自动建立和敏感信息保护的需求.

关键词：网络信任管理信任协商一致性验证器协商策略

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基于VMM层系统调用分析的软件完整性验证

计算机研究与发展 2011年第8期48卷 1438-1446页

作者：李博李建欣胡春明沃天宇怀进鹏北京航空航天大学计算机学院北京100191

在虚拟化云计算平台中,如何保证其上运行软件的可信性是云平台广泛应用的关键.完整性测量与验证技术是保证软件系统可信性的一种主要方法.然而,现有的软件完整性验证系统大多需要修改操作系统内核,很难为大规模虚拟机环境中的众多异构... 详细信息

在虚拟化云计算平台中,如何保证其上运行软件的可信性是云平台广泛应用的关键.完整性测量与验证技术是保证软件系统可信性的一种主要方法.然而,现有的软件完整性验证系统大多需要修改操作系统内核,很难为大规模虚拟机环境中的众多异构系统提供一致解决方案,且无法抵御内核级恶意攻击.针对当前方法在兼容性、安全性以及可管理性上存在的问题,设计并实现了一种在VMM层基于系统调用分析技术来验证软件完整性的方法VMGuard.它通过截获客户操作系统中的系统调用来识别软件加载,并基于系统调用关联性分析和虚拟机文件系统元数据重构技术来验证客户操作系统中软件的完整性.在Qemu和KVM两种主流虚拟化平台上实现了VMGuard,并通过实验评测VMGuard的有效性和性能.实验结果表明,VMGuard能够有效验证客户操作系统中软件的完整性,且性能开销在10%以内.

关键词：云计算虚拟化完整性验证系统调用分析软件加载