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On Constacyclic Codes over Zp1p2…pt
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作者 Derong XIE Qunying LIAO 《数学年刊:B辑英文版》 SCIE CSCD 2019年第4期555-566,共12页
Let t ≥ 2 be an integer, and let p1, ···, ptbe distinct primes. By using algebraic properties, the present paper gives a sufficient and necessary condition for the existence of non-trivial self-orthogo... Let t ≥ 2 be an integer, and let p1, ···, ptbe distinct primes. By using algebraic properties, the present paper gives a sufficient and necessary condition for the existence of non-trivial self-orthogonal cyclic codes over the ring Zp1p2···ptand the corresponding explicit enumerating formula. And it proves that there does not exist any self-dual cyclic code over Zp1p2···pt. 展开更多
关键词 IDEAL ISOMORPHISM Constacyclic CODE Self-orthogonal CODE Self-orthogonal CYCLIC CODE
GPS静态精密单点定位算法精度分析 被引量:1
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作者 符华年 张旭东 胡玉坤 《测绘通报》 CSCD 北大核心 2019年第2期95-98,共4页
采用精密轨道和钟差,利用Bernese软件解算得到亚洲地区13个IGS跟踪站的站坐标、对流层ZTD和接收机钟差,将解算的结果与CODE发布的结果对比发现:静态PPP算法解算的N方向收敛精度明显优于E方向和U方向,4~6 h后,坐标偏差在1 cm左右;NEU RM... 采用精密轨道和钟差,利用Bernese软件解算得到亚洲地区13个IGS跟踪站的站坐标、对流层ZTD和接收机钟差,将解算的结果与CODE发布的结果对比发现:静态PPP算法解算的N方向收敛精度明显优于E方向和U方向,4~6 h后,坐标偏差在1 cm左右;NEU RMS均值分别为0.45、0.29、0.69 cm,ZTD RMS均值为0.85 cm,接收机钟差RMS均值为0.14 ns。试验表明:精密单点定位算法具有较高的精度和可靠性,可为实际工程测量及相关地球物理信号研究提供理论依据。 展开更多
关键词 CODE IGS跟踪站 对流层ZTD 接收机钟差
Toward using Cloud Elasticity on the Internet of Things Landscape 预览
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作者 Rodrigo da Rosa Righi Márcio Miguel Gomes +2 位作者 Cristiano Andrá da Costa Helge Parzyjegla Hans-Ulrich Heiss 《大数据与云创新》 2019年第1期1-20,共20页
The digital universe is growing at significant rates in recent years. One of the main responsible for this sentence is the Internet of Things (IoT), or IoT, which requires a middleware that should be capable to handle... The digital universe is growing at significant rates in recent years. One of the main responsible for this sentence is the Internet of Things (IoT), or IoT, which requires a middleware that should be capable to handle this increase of data volume at real time. Particularly, data can arrive in the middleware in parallel as in terms of input data from radiofrequency identification readers as request-reply query operations from the user’s side. Solutions modeled at software, hardware, and/or architecture levels present limitations to handle such load, facing the problem of scalability in the IoT scope. In this context, this article presents a model denoted Eliot - elasticity-driven IoT - which combines both cloud and high-performance computing to address the IoT scalability problem in a novel electronic product code (EPC) global-compliant architecture. Particularly, we keep the same application programming interface but offer an elastic EPC information services (EPCISs) component in the cloud, which is designed as a collection of virtual machines (VMs) that are allocated and deallocated on the fly in accordance with the system load. Based on the Eliot model, we developed a prototype that could run over any black box EPCglobal-compliant middleware. We selected the Fosstrak for this role, which is currently one of the most used IoT middlewares. Thus, the prototype acts as an upper layer over the Fosstrak to offer a better throughput and latency performances in an effortless way. The results are encouraging, where Eliot outperforms the non-elastic approach both in terms of response time and request throughput. 展开更多
关键词 Internet of THINGS CLOUD ELASTICITY ELECTRONIC PRODUCT CODE global Performance Adaptivity ELECTRONIC PRODUCT CODE information services
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给水排水和消防设计规范关联性问题探讨 预览
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作者 刘洪令 《给水排水》 CSCD 北大核心 2019年第4期140-144,共5页
给水排水和消防设计需要遵循较多的设计规范,在实际工程设计中,发现一些相关规范的关联性条文存在不协调的现象。针对现行给水排水设计规范及相关建筑规范的规定,对规范间关联性条文在工程设计中出现的不协调、执行难等问题进行了系统分... 给水排水和消防设计需要遵循较多的设计规范,在实际工程设计中,发现一些相关规范的关联性条文存在不协调的现象。针对现行给水排水设计规范及相关建筑规范的规定,对规范间关联性条文在工程设计中出现的不协调、执行难等问题进行了系统分析,指出了规范编制中加强关联性条文的协调性、统一性,对工程设计的质量保证具有重要意义。 展开更多
关键词 规范 关联性 消防水箱补水管标高 厨房排水地漏 同层排水 轻便水龙
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Polychronous automata and their use for formal validation of AADL models
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作者 Thierry GAUTIER Clement GUY +3 位作者 Alexandre HONORAT Paul LE GUERNIC Jean-Pierre TALPIN Loic BESNARD 《中国计算机科学前沿:英文版》 SCIE EI CSCD 2019年第4期677-697,共21页
This paper investigates how state diagrams can be best represented in the polychronous model of computation (MoC) and proposes to use this model for code validation of behavior specifications in architecture analysis ... This paper investigates how state diagrams can be best represented in the polychronous model of computation (MoC) and proposes to use this model for code validation of behavior specifications in architecture analysis & design language (AADL). In this relational MoC, the basic objects are signals, which are related through dataflow equations. Signals are associated with logical clocks, which provide the capability to describe systems in which components obey multiple clock rates. We propose a model of finite-state automata, called polychronous automata, which is based on clock relationships. A specificity of this model is that an automaton is submitted to clock constraints, which allows one to specify a wide range of control-related configurations, being either reactive or restrictive with respect to their control environment. A semantic model is defined for these polychronous automata, which relies on boolean algebra of clocks. Based on a previously defined modeling method for AADL software architectures using the polychronous MoC, the proposed model is used as a formal model for the AADL behavior annex. This is illustrated with a case study involving an adaptive cruise control system. 展开更多
关键词 architecture modeling FORMAL SEMANTICS finitestate AUTOMATON polychronous model synchronous CONCURRENCY code generation AADL
轴心受压构件稳定承载力的规范差异研究 预览
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作者 陈娟婷 陈素华 《钢结构(中英文)》 2019年第9期79-82,102共5页
由于我国建筑和交通领域钢结构行业设计标准的不同,各个规范体系下的同一构件的稳定性计算结果也不尽相同,通过一则轴心受压构件稳定承载力的计算实例,详细比较其应力比的差别并分析其差异产生的原因,希望推进业内对该问题的进一步研究。
关键词 轴心受压 稳定 规范
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Template-based AADL automatic code generation
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作者 Kai HU Zhangbo DUAN +2 位作者 Jiye WANG Lingchao GAO Lihong SHANG 《中国计算机科学前沿:英文版》 SCIE EI CSCD 2019年第4期698-714,共17页
Embedded real-time systems employ a variety of operating system platforms. Consequently, for automatic code generation, considerable redevelopment is needed when the platform changes. This results in major challenges ... Embedded real-time systems employ a variety of operating system platforms. Consequently, for automatic code generation, considerable redevelopment is needed when the platform changes. This results in major challenges with respect to the automatic code generation process of the architecture analysis and design language (AADL). In this paper, we propose a method of template-based automatic code generation to address this issue. Templates are used as carriers of automatic code generation rules from AADL to the object platform. These templates can be easily modified for different platforms. Automatic code generation for different platforms can be accomplished by formulating the corresponding generation rules and transformation templates. We design a set of code generation templates from AADL to the object platform and develop an automatic code generation tool. Finally, we take a typical data processing unit (DPU) system as a case study to test the tool. It is demonstrated that the autogenerated codes can be compiled and executed successfully on the object platform. 展开更多
关键词 REAL-TIME system TEMPLATE FORMAL methods AADL automatic CODE GENERATION
西门子Multimobil 10移动X光机无代码故障的分析与维修 预览
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作者 张冕 程广斌 +1 位作者 杨洪钢 刘阳 《中国医疗器械信息》 2019年第13期180-181,共2页
介绍西门子Multimobil 10移动X光机的无故障代码的案例,从分析其框图组成入手,做出了详细分析最后尝试解决了问题。
关键词 移动床边X射线机 故障 代码
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时间密码CODE 11.59
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作者 殷鹏 《商业周刊(中文版)》 2019年第15期86-88,共3页
爱彼(Audemars Piguet)CODE 11.59系列腕引起制表业热议。13枚腕表搭载6款白产机芯,其中包括4款复杂功能时计,这个自产能力非常强大。CODE 11.59系列也是爱彼首次推出同时适合男士与女士佩戴的腕表系列,表壳圆弧的流线造型造就绝佳的佩... 爱彼(Audemars Piguet)CODE 11.59系列腕引起制表业热议。13枚腕表搭载6款白产机芯,其中包括4款复杂功能时计,这个自产能力非常强大。CODE 11.59系列也是爱彼首次推出同时适合男士与女士佩戴的腕表系列,表壳圆弧的流线造型造就绝佳的佩戴舒适度。 展开更多
关键词 CODE 密码 时间 舒适度 线造型 腕表 制表
基于ICEM-CFD的中子学力学耦合程序研制 预览
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作者 袁宝新 郑杰 +1 位作者 杨万奎 曾和荣 《装备环境工程》 CAS 2019年第2期32-36,共5页
目的针对反应堆工程分析中面临的中子学力学耦合这一问题,在同一软件框架下实现中子学力学多物理场计算。方法利用商业CAD前处理软件ICEM-CFD对堆芯几何进行网格剖分,开发基于有限元方法的中子学力学耦合计算程序,对同一堆芯网格划分进... 目的针对反应堆工程分析中面临的中子学力学耦合这一问题,在同一软件框架下实现中子学力学多物理场计算。方法利用商业CAD前处理软件ICEM-CFD对堆芯几何进行网格剖分,开发基于有限元方法的中子学力学耦合计算程序,对同一堆芯网格划分进行中子学和力学计算。结果初步实现了基于同一软件框架下网格层面的中子学力学耦合计算,得到了中子学力学初步耦合的计算结果。结论通过基准例题对程序进行计算校验,该耦合程序计算能力是可信的。 展开更多
关键词 ICEM-CFD 中子学 力学 耦合 程序
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Decomposing Composite Changes for Code Review and Regression Test Selection in Evolving Software
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作者 Bo Guo Young-Woo Kwon Myoungkyu Song 《计算机科学技术学报:英文版》 SCIE EI CSCD 2019年第2期416-436,共21页
Inspecting and testing code changes typically require a significant amount of developer effort.As a system evolves,developers often create composite changes by mixing multiple development issues,as opposed to addressi... Inspecting and testing code changes typically require a significant amount of developer effort.As a system evolves,developers often create composite changes by mixing multiple development issues,as opposed to addressing one independent issue—an atomic change.Inspecting composite changes often becomes time-consuming and error-prone.To test unrelated edits on composite changes,rerunning all regression tests may require excessive time.To address the problem,we present an interactive technique for change decomposition to support code reviews and regression test selection,called ChgCutter.When a developer specifies code change within a diff patch,ChgCutter partitions composite changes into a set of related atomic changes,which is more cohesive and self-contained regarding the issue being addressed.For composite change inspection,it generates an intermediate program version that only includes a related change subset using program dependence relationships.For cost reduction during regression testing,it safely selects only affected tests responsible for changes to an intermediate version.In the evaluation,we apply ChgCutter to 28 composite changes in four open source projects.ChgCutter partitions these changes with 95.7% accuracy,while selecting affected tests with 89.0% accuracy.We conduct a user study with professional software engineers at PayPal and find that ChgCutter is helpful in understanding and validating composite changes,scaling to industry projects. 展开更多
关键词 SOFTWARE maintenance and evolution CODE review test SELECTION PROGRAM SLICING
伯恩斯坦“语码”理论对阶层固化问题的分析与解决 预览
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作者 徐苗苗 《学术交流》 CSSCI 北大核心 2019年第4期137-144,192共9页
语言社会学家巴兹尔·伯恩斯坦受到布迪厄的符号暴力论、萨丕尔语言实在论与福柯的权力话语观的影响,提出"语码"概念,并将语码分化作为社会阶层固化的根源,在此基础上,伯恩斯坦探究了语码分化背后的社会权力关系结构:一... 语言社会学家巴兹尔·伯恩斯坦受到布迪厄的符号暴力论、萨丕尔语言实在论与福柯的权力话语观的影响,提出"语码"概念,并将语码分化作为社会阶层固化的根源,在此基础上,伯恩斯坦探究了语码分化背后的社会权力关系结构:一方面强调社会权力关系结构对语码形成的决定作用,另一方面则指出语码对维护社会权力关系结构的反作用。为解决这一问题,伯恩斯坦主张应在家庭教育中保持两种语码的均衡,在学校教育中去除刻板印象的影响,应关注语码转换过程中的情境要素,通过这三个途径实现教育场域的话语建构,以重新整合分化的社会阶层,打破语码分化对社会流动的限制。 展开更多
关键词 巴兹尔·伯恩斯坦 语码 阶层 权力关系
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埃及规范对确定土层基本物理力学参数的要求 预览
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作者 付开隆 李朝辉 杨举 《高速铁路技术》 2019年第5期15-20,共6页
本文通过埃及斋月十日城项目及货运铁路的初勘全过程实际工作,搜集了丰富的现场及实验室有关数据,较系统全面地总结了照埃及规范确定土层基本物理力学参数的方法,并与我国相关规范进行对比,可为埃及其它工程提供借鉴。
关键词 埃及 规范 勘察 标准贯入 颗粒分析 试验
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季冻区客运专线隧道局部存水冻胀对衬砌力学性能的影响分析 预览
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作者 王雪来 崔光耀 +1 位作者 侯占鳌 吕晓聪 《高速铁路技术》 2019年第5期21-24,40共5页
本文依托吉图珲客运专线五峰山隧道,运用局部存水冻胀模型,采用有限元数值模拟技术,对不同积冰位置情况下,局部存水冻胀力对隧道衬砌力学性能的影响进行了分析。研究结果表明:(1)局部存水冻胀将对隧道结构安全造成一定的不利影响,存水... 本文依托吉图珲客运专线五峰山隧道,运用局部存水冻胀模型,采用有限元数值模拟技术,对不同积冰位置情况下,局部存水冻胀力对隧道衬砌力学性能的影响进行了分析。研究结果表明:(1)局部存水冻胀将对隧道结构安全造成一定的不利影响,存水位置不同,影响程度有所差别;(2)积冰位置处弯矩值较未积冰时显著提高,当隧道拱顶、拱肩、拱腰处积冰时,隧道安全系数相较于无冻胀力作用时都会降低,且当拱顶处积冰时,安全系数降低更为显著。研究成果可为季冻区隧道抗冻设计及冻害整治提供参考。 展开更多
关键词 季冻区 客运专线 隧道 局部存水冻胀 力学性能
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Designing a nuclear battery based on the Mo-99 radioactive source soluble in water and aqua regia in order to use in early tests 预览
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作者 Zohreh Movahedian Hossein Tavakoli-Anbaran 《核技术:英文版》 SCIE CAS CSCD 2019年第3期37-45,共9页
Today, millions of electrocommunication, electric, medical, and industrial devices use battery. Batteries with long life and high energy density seem to be essential in medical, military, oil and mining, aerospace are... Today, millions of electrocommunication, electric, medical, and industrial devices use battery. Batteries with long life and high energy density seem to be essential in medical, military, oil and mining, aerospace areas as well as conditions in which access is difficult and in situations where replacement or recharging of battery is costly. In this regard, the use of radiation energy resulting from radioactive materials and its conversion to electric energy can be effective in making batteries. In the present study, various Mo-99 radioisotope values with a half-life of 65.98 h were used as a soluble radioactive source in two materials of water and aqua regia. Then, by comparing the results of the Monte Carlo simulations program MCNPX for these two solutions, it was found that when the water is used instead of aqua regia (for idealization), the values of the superficial current of electrons, the volumetric flux of electrons, and the deposited energy in the volume containing the radioactive solution increased by 10.80, 4.10, and 13.80%, respectively. Also, the short-circuit current and energy conversion efficiency of this battery with a concentration of 0.01 molar, Mo-99 dissolved in the aqua regia are 0.79 lA and 16.47%, respectively. 展开更多
关键词 Nuclear battery RADIOACTIVE solution MCNPX code Mo-99
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Different cracking temperature rice straw biological carbon on SoilCh4,N2O Emissions Influence Analysis 预览
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作者 Hai Zhao 《探索-土壤科学》 2019年第1期13-19,共7页
Biological carbon can effective reducing greenhouse gas(Ch4,N2O)EmissionsDifferent cracking temperature under biological carbon of paddy field soilCh4,N2OEmissions of influence and mechanism need to further explore.Th... Biological carbon can effective reducing greenhouse gas(Ch4,N2O)EmissionsDifferent cracking temperature under biological carbon of paddy field soilCh4,N2OEmissions of influence and mechanism need to further explore.This study use two Raw Material Origin(Harbin,Danyang)Rice Straw biological carbonTo Jiangsu Province Danyang typical rice rotation field for study areaStudy Applied Different cracking temperature rice straw biological carbon on SoilCh4,N2OEmissions of influence.Results show that:(1)Compared with conventional fertilizationApplied300,500,700Crack Solution of Danyang and Harbin rice straw biological carbonCh4Cumulative emissions respectively reduce10.38%,21.09%,13.28%And42.83%,65.29%,55.44%N2OCumulative emissions respectively reduce42.77%,53.54%,51.19%And45.34%,48.51%,48.40%;(2)By greenhouse gas emissions strength formula calculatedApplied500 Cracking of Danyang and Harbin rice straw biological carbon respectively300 ,700 Reduce27.09%,25.85%And40.54%,8.09%;(3)Analysis500 Crack Solution Temperature of biological carbon emission reduction effect is better300 ,700 The main reason is applied three cracking biological carbon afterSoil of methane ancient Bacteria abundance value reduceAnd500 Lower300 ,700 Biological CarbonAverage reduce48.33%,29.35%.At the same time applied500 Biological carbon soil nitrification bacteria abundance lower than applied300 ,700 Students. 展开更多
关键词 X712 LITERATURE identification CODE
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Z编码的使用分析及对策
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作者 江千红 徐敏慧 +2 位作者 郑盼 吴丽娟 郭佳奕 《中国病案》 2019年第4期33-36,共4页
国际疾病分类第21章Z编码(Z00-Z99)是最后分类章,用于归类影响健康状态和与保健机构接触的因素。Z编码由于与ICD-10的其他章节差别较大,同时涉及到内外妇儿等多个临床科室,使用率较高,故在实际编码工作中较易出现问题。通过病案回顾分... 国际疾病分类第21章Z编码(Z00-Z99)是最后分类章,用于归类影响健康状态和与保健机构接触的因素。Z编码由于与ICD-10的其他章节差别较大,同时涉及到内外妇儿等多个临床科室,使用率较高,故在实际编码工作中较易出现问题。通过病案回顾分析的方式,对部分Z编码的使用进行分析,指出易错编码、漏编码的情况,有效结合编码原则与病案首页诊疗信息基础上作出正确编码。医疗机构应当通过专业培训提升编码员技术能力,加强编码员与临床医师的双向沟通等措施,不断提高编码准确性,为开展卫生信息统计、医疗质量管理、DRGs工作,提供高质量的数据信息。 展开更多
关键词 Z编码 ICD-10 使用分析
花山岩画文化创意产品创新设计模型探究 预览
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作者 林俊宏 《工业设计》 2019年第8期125-126,共2页
探究花山岩画文化创意产品的创新设计模型路径,分析花山岩画具有多重身份以及当前花山岩画文化创意产品设计的研究现状,分别从花山岩画的“三化”和其文化创意产品设计的“三特色”进行编码,探究花山岩画文化创意产品创新设计的新思路。
关键词 花山岩画 文化创意产品 创新设计 编码 模型
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A Query Expansion Method Based on Evolving Source Code
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作者 JIN Huan XIONG Lei 《武汉大学学报:自然科学英文版》 CAS CSCD 2019年第5期391-399,共9页
The existing query expansion(QE) methods cannot find the most users-requested source code version at times due to the over-expansion resulting from noises. To solve this problem, we propose a QE method based on evolvi... The existing query expansion(QE) methods cannot find the most users-requested source code version at times due to the over-expansion resulting from noises. To solve this problem, we propose a QE method based on evolving contexts(EC) that are added/deleted terms and their dependent terms during code evolution. On expanding a query, we appended the added terms as relevant terms, and excluded the deleted terms as noisy terms. We also developed a QE-integrating framework based on the Support Vector Machine(SVM) Ranking, called QESR, to simultaneously integrate multiple QE methods. Our experiment shows that QESR outperforms the state-of-the-art QE methods CodeHow and Query Expansion based on Crowd Knowledge(QECK) by 13%-16% in terms of precision when the first query result is inspected. 展开更多
关键词 code SEARCH QUERY EXPANSION crowd KNOWLEDGE EVOLVING CONTEXT
Code Attention: translating source code to comments by exploiting the code constructs
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作者 Wenhao ZHENG Hongyu ZHOU +1 位作者 Ming LI Jianxin WU 《中国计算机科学前沿:英文版》 SCIE EI CSCD 2019年第3期565-578,共14页
Appropriate comments of code snippets provide insight for code functionality, which are helpful for program comprehension. However, due to the great cost of authoring with the comments, many code projects do not conta... Appropriate comments of code snippets provide insight for code functionality, which are helpful for program comprehension. However, due to the great cost of authoring with the comments, many code projects do not contain adequate comments. Automatic comment generation techniques have been proposed to generate comments from pieces of code in order to alleviate the human efforts in annotating the code. Most existing approaches attempt to exploit certain correlations (usually manually given) between code and generated comments, which could be easily violated if coding patterns change and hence the performance of comment generation declines. In addition, recent approaches ignore exploiting the code constructs and leveraging the code snippets like plain text. Furthermore, previous datasets are also too small to validate the methods and show their advantage. In this paper, we propose a new attention mechanism called CodeAttention to translate code to comments, which is able to utilize the code constructs, such as critical statements, symbols and keywords. By focusing on these specific points, CodeAttention could understand the semantic meanings of code better than previous methods. To verify our approach in wider coding patterns, we build a large dataset from open projects in GitHub. Experimental results in this large dataset demonstrate that the proposed method has better performance over existing approaches in both objective and subjective evaluation. We also perform ablation studies to determine effects of different parts in CodeAttention. 展开更多
关键词 software mining machine learning CODE COMMENT generation recurrent neural network ATTENTION mechanism
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