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A community-centric approach to automated service composition

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Science china(Information Sciences) 2010年第1期53卷 50-63页

作者： liu xuanzhe1,2, huang gang1,2.& mei hong1,2.1School of Electronics Engineering and Computer Science, peking university, beijing 100871, china 2key laboratory of high confidence software technologies, ministry of education, peking university, beijing 100871, china School of Electronics Engineering and Computer Science Peking University key laboratory of high confidence software technologies Ministry of Education Peking University

In the recent years, the web has kept growing rapidly and undergone tremendous changes towards a user-centric environment. With the proliferation of services available on the Internet, millions of users are able to voluntarily participate in and collaborate for their own interests and benefits by means of service composition. However, due to the ever increasing number of services, it then becomes a challenging issue to enable the users to rapidly select and compose the proper services. In this paper, we propose an approach which utilizes service communities for automated service composition. This paper makes three contributions. Firstly, we propose the service community architecture and identify two key components to facilitate service discovery and composition. Secondly, assisted by the service community, we provide two composition types to help users explore the space of potential composition opportunities without having to understand too many details of individual candidate services. Finally, we evaluate our approach by performance analysis and provide a web-based prototype that lowers the entry barrier for the users.

关键词： services computing service composition service community

A software architecture centric self-adaptation approach for Internetware

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Science in china(Series F) 2008年第6期51卷 722-742页

作者： mei hong1,2, huang gang1,2, LAN Ling1,2.& LI JunGuo1,2.1 key laboratory of high confidence software technologies (peking university), ministry of education, beijing 100871, china 2 School of Electronics Engineering and Computer Science, peking university, beijing 100871, china key laboratory of high confidence software technologies (peking university) Ministry of Education School of Electronics Engineering and Computer Science Peking University

Being one of the basic features of Internetware, self-adaptation means that the software system can monitor its runtime state and behavior and adjust them when necessary according to pre-defined policies. Focusing on the three fundamental issues of self-adaptation, including the scope, operability and trustworthiness, a software architecture （SA） centric approach for Internetware＇s self-adaptation is presented in this paper. All of the self-adaptive actions, i.e. monitoring, analyzing, planning and executing, are performed based on SA. In detail, runtime state and behavior of Internetware are represented and changed in the form of runtime soft- ware architecture. The knowledge for self-adaptation is captured, organized and reasoned in the form of SA so that automatic analysis and decision-making are achieved.

关键词： Internetware self-adaptation software architecture middleware

Towards module-based automatic partitioning of Java applications

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Frontiers of Computer Science 2012年第6期6卷 725-740页

作者： Ying ZHANG gang huang Wei ZHANG xuanzhe liu hong mei key laboratory of high confidence software technologies(peking university) Ministry of EducationBeijing 100871China School of Electronics Engineering and Computer Science Peking UniversityBeijing 100871China

When reengineering a monolithic application to be a distributed one, programmers always have to decide how many distributed parts the application should be partitioned, and write many codes related to where a part will be placed on network nodes and how these parts communicate with each other through the network. These codes usually have nothing to do with the business functions of the application, and they are laborious to write. In addition, as the distribution architecture of the application is finalized beforehand, it may not adapt well to the everchanging execution environment. In this paper, we propose DPartner, an automatic partitioning system, to help programmers create a distributed Java application without explicitly writing the distribution-related codes. Unlike the other partitioning systems, DPartner does not partition an application directly into the coarse-grained client and server. Instead, it first partitions the application into several modules where each module performs a relatively independent business function of the application. Then it makes these modules be distributable through automatic bytecode rewriting. These modules can distribute in different nodes and cooperate to work just as the original monolithic application. Such a module-based partitioning approach enables a relatively easy reshaping of the distribution architecture of an application, which facilitates the application adapt to the environmental changes without manual recoding or repartitioning with regard to distribution. This paper gives the detailed design of DPartner, and evaluates it using real-world applications. The evaluation results demonstrate the effectiveness and efficiency of DPartner.

关键词： application partitioning distributed computing,DPartner

iMashup:a mashup-based framework for service composition

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Science china(Information Sciences) 2014年第1期57卷 5-24页

作者： liu xuanzhe huang gang ZHAO Qi mei hong BLAKE M.Brian key laboratory of high confidence software technologies (peking university) Ministry of Education School of Electronics Engineering and Computer Science Peking University Department of Computer Science and Engineering University of Notre Dame

The Web has undergone a tremendous change from a primarily publication platform towards a participatory and"programmable"platform,where a large number of heterogeneous Web-delivered services(including SOAP and RESTful Web services,RSS and Atom feeds)are *** results in the creation of Web mashup applications with rich user ***,the integration of Web-delivered services is still a challenging *** not only requires the developers’tedious eforts in understanding and coordinating heterogeneous service types,but also results in the time-consuming development of user *** this paper,we propose the iMashup composition framework to facilitate mashup development and *** provide a unified mashup component model for the common representation of heterogeneous Web-delivered service *** component model specifies necessary properties and behaviors at both business and user interface *** associate the component model with semantically meaningful tags,so that mashup developers can fast understand the service *** mashup developers can search and put the proper mashup components into the Web browser based composition environment,and connect them by data flows based on the tag-based *** an integration manner might prevent some low-level programming eforts and improve the composition efciency.A series of experimental study are conducted to evaluate our framework.

关键词： service composition mashup component model Web-delivered service

software techniques for Internet Computing:Current situation and future trend

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Chinese Science Bulletin 2010年第31期55卷 3510-3516页

作者： mei hong liu xuanzhe key laboratory of high confidence software technologies(peking university) Ministry of EducationBeijing 100871China School of Electronics Engineering and Computer Science Peking UniversityBeijing 100871China

The fast development of the Internet has extended wider space for Information and Communications Technology(ICT),and it has brought a series of challenges for traditional software theories,models,approaches and *** paper looks back some popular Internet-based new computing paradigms and application schemas,discusses the current status and the future trend of software technologies for Internet Computing,including topics of software model,software runtime supporting platform,software development methodologies and software quality measurement and assurance.

关键词： Internet software technique software methodology Internetware

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网构软件研究:回顾与展望

科学通报 2022年第32期67卷 3780-3792页

作者：梅宏黄罡刘譞哲张颖北京大学计算机学院北京100871 高可信软件技术教育部重点实验室(北京大学) 北京100871

软件作为计算系统的“灵魂”,是信息技术产业的核心组成部分,也正在成为数字经济时代支撑社会运行的重要“基础设施”.进入21世纪以来,互联网及其延伸网络形成了开放、动态、难控的复杂计算环境,对传统的软件范型与技术提出了巨大挑战,... 详细信息

软件作为计算系统的“灵魂”,是信息技术产业的核心组成部分,也正在成为数字经济时代支撑社会运行的重要“基础设施”.进入21世纪以来,互联网及其延伸网络形成了开放、动态、难控的复杂计算环境,对传统的软件范型与技术提出了巨大挑战,也蕴含了技术体系重大变革的新机遇.来自北京大学、南京大学和中国科学院的学者于2000年提出“网构软件”这一面向互联网的新型软件范型,经过20余年的努力,在其基本模型、开发方法、运行支撑和质量评估与保障等方面,均取得一系列重要的研究进展,形成了系统化的创新成果,产生了广泛的学术和产业影响.本文从软件范型入手,以互联网及其延伸网络形成的复杂计算环境为线索,回顾网构软件的研究进展,并展望未来的研究工作.

关键词：互联网软件范型网构软件软件体系结构

面向移动Web应用的浏览器缓存性能度量与优化

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软件学报 2020年第7期31卷 1980-1996页

作者：马郓刘譞哲梅宏清华大学软件学院北京100084 高可信软件技术教育部重点实验室(北京大学) 北京100871

随着移动互联网的飞速发展,用户越来越多地通过移动设备访问Web应用.浏览器为Web应用提供基本的计算、渲染等运行时支撑,其缓存机制可以支持Web应用直接从本地而不是通过网络来获取可复用资源,不仅能够减少整体的执行时间从而提升应用... 详细信息

随着移动互联网的飞速发展,用户越来越多地通过移动设备访问Web应用.浏览器为Web应用提供基本的计算、渲染等运行时支撑,其缓存机制可以支持Web应用直接从本地而不是通过网络来获取可复用资源,不仅能够减少整体的执行时间从而提升应用加载速度,还能够减少网络流量使用和电池电量消耗,从而保证移动Web用户体验.近年来,围绕面向移动Web应用的浏览器缓存优化得到了国内外学术界和工业界的广泛关注.然而,现有研究工作大多都是从网络层面关注浏览器缓存的整体性能,未充分考虑移动互联网用户访问行为的差异性和动态性,以及Web应用自身持续演化对浏览器实际缓存性能的影响.针对这一问题,首先设计了一种新型主动式缓存度量实验,通过仿真用户的访问行为来分析移动Web应用实际资源使用情况,揭示了浏览器缓存的理论性能上限和实际性能之间的巨大差距,并发现了造成这一差距的3个主要原因:重复请求别名资源、启发式过期时间和保守的过期时间配置.基于此发现,从应用层和平台层分别提出了两种浏览器缓存性能优化方案,并实现了原型系统.实验结果表明,采用两种方法分别平均可减少8%~51%和4%~58%的网络流量,且系统开销较小.

关键词：移动Web应用浏览器缓存性能度量性能优化

Association between Perceived Stressfulness of Stressful Life Events and the Suicidal Risk in Chinese Patients with Major Depressive Disorder

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Chinese Medical Journal 2018年第8期131卷 912-919页

作者： Jing-Yu Lin Yu huang Yun-Ai Su Xin Yu Xiao-Zhen Lyu Qi liu Tian-mei Si Clinical Psychopharmacology Division Peking University Sixth Hospital National Clinical Research Center for Mental Disorders and Key Laboratory of Mental Health Ministry of Health (Peking University) Beijing 100191 China National Engineering Research Center for software Engineering Peking University Beijing 100871 China

Background： Patients with major depressive disorder （MDD） usually have high risk of suicidality. Few studies have investigated the effects of stressful life events （SLEs） on the risk of suicide in Chinese patients who have developed MDD. This study aimed to investigate the impact of SLEs on suicidal risk in Chinese patients with MDD. Methods： In total, 1029 patients with MDD were included from nine psychiatric hospitals to evaluate the impact of SLEs on suicidal risk. Patients fulfilling the Mini-International Neuropsychiatric Interview （MINI） criteria for MDD were included in the study. Patients were excluded if they had lifetime or current diagnoses of psychotic disorder, bipolar disorder, and alcohol or substance dependence. Depressive symptoms were assessed by the 17-item Harnilton Depression Scale （HAMD-17）. The suicidal risk of MDD patients was determined by the suicide risk module of MINI. SLEs were assessed by the Life Events Scale. Results： No gender difference was found for suicidal risk in MDD patients. Patients with suicidal risk had younger ages, lower education levels, more drinking behavior, and lower marriage rate, and fewer people had child and more severe depressive symptoms than nonsuicidal risk group. high-level perceived stressfulness （HPS） and number of SLEs that patients were exposed to were significantly greater in patients with suicidal risk than patients without. In multivariate logistic analysis, HPS of SLEs （odds ratio [OR] = 1.54, 95% confidence interval [C1]： 1.16-2.05, P = 0.003） and depressive symptoms （OR = 1.08.95% CI： 1.05-1.11, P 〈 0.001 ） were associated with suicidal risk even after adjustment of gender, age, marriage, drinking behavior, and childless. Conclusions： HPS of SLEs is associated with suicide risk in Chinese patients with MDD. Further suicide prevention programs targeting this risk factor are needed. Trial Registration： ***： NCT02023567; https：//***/ct2/show/NCTO2023567？term=NCTO2023567＆r

关键词： Life Stresses: Major Depressive Disorder: Suicide

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数据驱动的移动应用用户接受度建模与预测

软件学报 2020年第11期31卷 3364-3379页

作者：陆璇陈震鹏刘譞哲梅宏高可信软件技术教育部重点实验室(北京大学) 北京100871 北京大学软件工程研究所北京100871

应用市场(appmarket)已经成为互联网环境下软件应用开发和交付的一种主流模式.相对于传统模式,应用市场模式下,软件的交付周期更短,用户的反馈更快,最终用户和开发者之间的联系更加紧密和直接.为应对激烈的竞争和动态演变的用户需求,移... 详细信息

应用市场(appmarket)已经成为互联网环境下软件应用开发和交付的一种主流模式.相对于传统模式,应用市场模式下,软件的交付周期更短,用户的反馈更快,最终用户和开发者之间的联系更加紧密和直接.为应对激烈的竞争和动态演变的用户需求,移动应用开发者必须以快速迭代的方式不断更新应用,修复错误缺陷,完善应用质量,提升用户体验.因此,如何正确和综合理解用户对软件的接受程度(简称用户接受度),是应用市场模式下软件开发需考量的重要因素.近年来兴起的软件解析学(softwareanalytics)关注大数据分析技术在软件行业中的具体应用,对软件生命周期中大规模、多种类的相关数据进行挖掘和分析,被认为是帮助开发者提取有效信息、作出正确决策的有效途径.从软件解析学的角度,首先论证了为移动应用构建综合的用户接受度指标模型的必要性和可行性,并从用户评价数据、操作数据、交互行为数据这3个维度给出基本的用户接受度指标.在此基础上,使用大规模真实数据集,在目标用户群体预测、用户规模预测和更新效果预测等典型的用户接受度指标预测问题中,结合具体指标,提取移动应用生命周期不同阶段的重要特征,以协同过滤、回归融合、概率模型等方法验证用户接受度的可预测性,并讨论了预测结果与特征在移动应用开发过程中可能提供的指导.

关键词：用户接受度应用市场移动应用软件解析学数据驱动