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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. {2.,{2.,2.1School of Electronics Engineering and Computer Science, peking University, beijing 100871, china 2.8} laboratory of high confidence {12. technologies, Ministry of Education, peking University, beijing 100871, china 1. School of Electronics Engineering and Computer Science Peking University Beijing 100871 China2. Key Laboratory of High Confidence Software Technologies Ministry of Education Peking University Beijing 100871 China

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. {2.,2. LAN Ling1,2.& LI JunGuo1,{2. (peking University), Ministry of Education, beijing 100871, china 2.School of Electronics Engineering and Computer Science, peking University, beijing 100871, china 1. key laboratory of {2. {2. software technologies (peking University) Ministry of Education Beijing 100871 China 2. School of Electronics Engineering and Computer Science Peking University Beijing 100871 China

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 {2. liu hong mei key laboratory of {2. {2. 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 {2. {2. ZHAO Qi mei hong BLAKE M.Brian key laboratory of {2. {2. 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 {2. xuanzhe key laboratory of {2. {2. 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 {2. 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2.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2.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2.00年提出“网构软件”这一面向互联网的新型软件范型,经过2.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

Epidemiology and factors predicting survival of amyotrophic lateral sclerosis in a large Chinese cohort

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Chinese Medical Journal 2021年第18期134卷 2231-2236页

作者： Ming Gao Na liu Xue-mei Li liu-Wen Chao hong-Qi Lin Yan Wang Yan Sun Chen huang Xiao-{2. Li Min Deng Institute of Medical Innovation and Research Peking University Third HospitalBeijing 100191China Department of Neurology Peking University Third HospitalBeijing 100191China Department of Neurology Affiliated Hospital of Weifang Medical UniversityWeifangShandong 261000China Department of Anesthesiology Fuwai Central China Cardiovascular HospitalZhengzhouHenan 450000China

Background:Amyotrophic lateral sclerosis(ALS)is a fatal neurodegenerative disorder associated with loss of motor *** objective was to explore the epidemiology,clinical features,and survival factors of 1809 patients with ***:We analyzed 1809 ALS patients,who were recruited from the peking University Third Hospital from January 2.05 to December *** data and disease-related parameters were ***-meier curves were used to compare survival *** proportional hazards function and the hazard ratio were used to identify adjusted prognostic ***:The results showed that the average annual incidence in {2. alone was 0.38 cases/100,000 person-years and the mean age of onset was 48.88±11.35(95%{2. interval[CI]:48.17–49.85)*** median survival time from onset to death/tracheostomy was 58.89±33.03(95%CI:51.46–63.84)*** the adjusted Cox proportional hazard model,age of onset,diagnosis delay,rate of disease progression(Amyotrophic Lateral Sclerosis Functional Rating Scale Revised decline[points/month]),and body mass index all had an independent effect on survival in ***:Our study provides information on epidemiology,clinical features,and survival factors of patients with ALS in *** results can be helpful in clinical practice,clinical trial design,and validation of new tools to predict disease progression.

关键词： Amyotrophic lateral sclerosis Epidemiology Clinical features Occupation Survival factors

Low WT1 transcript levels at diagnosis predicted poor outcomes of acute myeloid leukemia patients with t(8;2.) who received chemotherapy or allogeneic hematopoietic stem cell transplantation

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Chinese Journal of Cancer 2016年第7期35卷 350-358页

作者： Ya-Zhen Qin Yu Wang hong-Hu Zhu Robert Peter Gale mei-Jie Zhang Qian Jiang Hao Jiang Lan-Ping Xu Huan Chen Xiao-Hui Zhang Yan-Rong {2. Yue-Yun Lai Bin Jiang Kai-Yan {2. Xiao-Jun huang peking University People's Hospital Peking University Institute of HematologyBeijing Key Laboratory of Hematopoietic Stem Cell Transplantation No.11 Xizhimen South Street Beijing P.R. China Haematology Research Center Division of Experimental MedicineDepartment of MedicineImperial College London London SW72AZUK Biostatistics Division Medical College of Wisconsin Milwaukee WI53226USA peking-Tsinghua Center for Life Sciences Beijing 100871P.R. China

Background:Acute myeloid leukemia(AML) with t(8;2.) is a heterogeneous *** AML patients with t(8;2.) who have a poor prognosis despite achieving remission is important for determining the best subsequent *** study aimed to evaluate the impact of Wilm tumor gene-1(WT1) transcript levels and cellular homolog of the viral oncogene v-KIT receptor tyrosine kinase(C-KIT) mutations at diagnosis,and RUNXTRUNX1T1 transcript levels after the second consolidation chemotherapy cycle on ***:Eighty-eight AML patients with t(8;2.) who received chemotherapy only or allogeneic hematopoietic stem cell transplantation(allo-HSCT) were *** who achieved remission,received two or more cycles of consolidation chemotherapy,and had a positive measureable residual disease(MRD) test result(defined as 1-RUNX1T1 transcript levels compared to baseline) after 2.8 cycles of consolidation chemotherapy were recommended to receive *** who had a negative MRD test result were recommended to receive further chemotherapy up to only 8 ***1 transcript levels and C-KIT mutations at diagnosis,and RUNX1-RUNX1T1 transcript levels after the second consolidation chemotherapy cycle were ***:Patients who had a C-KIT mutation had significantly lower WTl transcript levels than patients who did not have a C-KIT mutation(6.7%± 10.6%vs.19.5%± 19.9%,P 1).Low WTl transcript levels(high cumulative incidence of relapse in all patients(hazard ratio[HR]= 3.53,2.30,and 11.49;95%confidence interval[CI]1.64-7.6{2..82.7.56,and 4.43-2..82.P = 0.002.0.034,and 1,respectively);these conditions were also independently associated with low leukemia-free survival(HR =3.71,2.33,and 5.85;95%CI 1.82.7.56,1.17-4.64,and 2.75-12.44;P < 0.00

关键词：异基因造血干细胞移植转录水平白血病 WT1 患者化疗诊断预后

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