Abstract Model Checking for Web Services

Web-services are highly distributed programs, and concurrent software is notoriously error-prone. Model checking is a powerful technique to find bugs in concurrent systems. However, the existing model checkers have no enough ability to support for the programming languages and communication mechanisms used for Web services. We propose to use Kripke structures as means of modeling Web service. This paper presents an automated way to extract formal models from programs implementing Web services using predicate abstraction for abstract model checking. The abstract models are checked by means of a model checker that implements automatic abstraction refinement. These results enable the verification of the applications that implement Web services.

Abstract models for heat engines

We retrospect three abstract models for heat engines which include a classic abstract model in textbook of thermal physics,a primary abstract model for finite-time heat engines,and a refined abstract model for finite-time heat engines.The detailed models of heat engines in literature of finite-time thermodynamics may be mapped into the refined abstract model.The future developments based on the refined abstract model are also surveyed.

Masked Sentence Model Based on BERT for Move Recognition in Medical Scientific Abstracts

Purpose:Mo ve recognition in scientific abstracts is an NLP task of classifying sentences of the abstracts into different types of language units.To improve the performance of move recognition in scientific abstracts,a novel model of move recognition is proposed that outperforms the BERT-based method.Design/methodology/approach:Prevalent models based on BERT for sentence classification often classify sentences without considering the context of the sentences.In this paper,inspired by the BERT masked language model(MLM),we propose a novel model called the masked sentence model that integrates the content and contextual information of the sentences in move recognition.Experiments are conducted on the benchmark dataset PubMed 20K RCT in three steps.Then,we compare our model with HSLN-RNN,BERT-based and SciBERT using the same dataset.Findings:Compared with the BERT-based and SciBERT models,the F1 score of our model outperforms them by 4.96%and 4.34%,respectively,which shows the feasibility and effectiveness of the novel model and the result of our model comes closest to the state-of-theart results of HSLN-RNN at present.Research limitations:The sequential features of move labels are not considered,which might be one of the reasons why HSLN-RNN has better performance.Our model is restricted to dealing with biomedical English literature because we use a dataset from PubMed,which is a typical biomedical database,to fine-tune our model.Practical implications:The proposed model is better and simpler in identifying move structures in scientific abstracts and is worthy of text classification experiments for capturing contextual features of sentences.Originality/value:T he study proposes a masked sentence model based on BERT that considers the contextual features of the sentences in abstracts in a new way.The performance of this classification model is significantly improved by rebuilding the input layer without changing the structure of neural networks.

Influence of Software Modeling and Design on Domain-Specific Abstract Thinking: Student’s Perspective

Software engineering has been taught at many institutions as individual course for many years. Recently, many higher education institutions offer a BSc degree in Software Engineering. Software engineers are required, especially at the small enterprises, to play many roles, and sometimes simultaneously. Beside the technical and managerial skills, software engineers should have additional intellectual skills such as domain-specific abstract thinking. Therefore, software engineering curriculum should help the students to build and improve their skills to meet the labor market needs. This study aims to explore the perceptions of software engineering students on the influence of learning software modeling and design on their domain-specific abstract thinking. Also, we explore the role of the course project in improving their domain-specific abstract thinking. The study results have shown that, most of the surveyed students believe that learning and practicing modeling and design concepts contribute to their ability to think abstractly on specific domain. However, this finding is influenced by the students’ lack of the comprehension of some modeling and design aspects (e.g., generalization). We believe that, such aspects should be introduced to the students at early levels of software engineering curriculum, which certainly will improve their ability to think abstractly on specific domain.

Conversion of Object Oriented System into Software Product Line with Delta Modeling Abstract Behavioral Specification

This article contains a system conversion from object oriented design into Software Product Line (SPL) using delta modeling of Abstract Behavioral Specification (ABS). ABS is a modeling language which targets system with high level of variety and supports SPL development with delta modeling. The case study of this thesis is a digital library system called Library Automation and Digital Archive (LONTAR). Originally, LONTAR only uses SOAP-based web service. With ABS, LONTAR will be converted into SPL and implement another web service called REST. The motivation of this conversion of LONTAR from object oriented into SPL is because it is easier to develop system with ABS than using regular object oriented. Product definition in ABS is relatively easier than creating a new subclass and do customization to make it works well.

竞技运动专家的认知优势及其形成机制——基于自动性特点和抽象化表征

目前对于竞技运动专家如何从长期训练中获得和迁移、提炼和更新专业知识与技能的机制尚未有清晰的阐释。基于专家-新手范式的研究表明,从表征学习的角度看竞技运动专家的认知优势主要体现在注意优势和记忆优势两方面,而竞技运动专家知识与技能的自动性特点和抽象化表征是其认知优势效应形成的两个关键原因。从生成模型的角度探讨竞技运动专家知识系统的抽象化表征机制,为能更好地理解竞技运动专家的认知优势效应,助其突破认知局限性提供了新的理论依据。

数学基本思想在集合教学中的运用

为帮助学生全面深入地理解集合概念,对数学基本思想在集合教学中的运用进行了研究。数学基本思想一般包括抽象、推理与模型,教师从集合概念的抽象性、集合关系的抽象性出发,引导学生理解数学抽象思想;从集合推理运算的基础、集合恒等式的推理与证明出发,引导学生理解数学推理思想;从计数与概率论、数理逻辑中的集合模型出发,引导学生理解数学模型思想。

Review of Software Model-Checking Techniques for Dealing with Error Detection in Program Codes

Debugging software code has been a challenge for software developers since the early days of computer programming. A simple need, because the world is run by software. So perhaps the biggest engineering challenge is finding ways to make software more reliable. This review provides an overview of techniques developed over time in the field of software model checking to solve the problem of detecting errors in program code. In addition, the challenges posed by this technology are discussed and ways to mitigate them in future research and applications are proposed. A comprehensive examination of the various model verification methods used to detect program code errors is intended to lay the foundation for future research in this area.

外部注意力增强语义交互的阅读理解模型

针对传统抽取式阅读理解模型未充分考虑问答样本之间潜在相关性的问题,通过RoBERTa对问题与段落进行编码,利用外部注意力Exatt增强语义交互层特征获取能力,提出外部注意力增强语义交互的阅读理解模型,捕获问题与段落中蕴涵的语义特征和不同问答样本之间的潜在相关性。实验结果表明,在CMRC2018和构建的电力安规问答数据集上,在评价指标EM和F1两方面,该方法较基线模型分别最高提高了0.737%和2.556%。

基于误差分治的神经网络验证

随着神经网络技术的快速发展,其在自动驾驶、智能制造、医疗诊断等安全攸关领域得到了广泛应用,神经网络的可信保障变得至关重要.然而,由于神经网络具有脆弱性,轻微的扰动经常会导致错误的结果,因此采用形式化验证的手段来保障神经网络安全可信是非常重要的.目前神经网络的验证方法主要关注分析的精度,而易忽略运行效率.在验证一些复杂网络的安全性质时,较大规模的状态空间可能会导致验证方法不可行或者无法求解等问题.为了减少神经网络的状态空间,提高验证效率,提出一种基于过近似误差分治的神经网络形式化验证方法.该方法利用可达性分析技术计算非线性节点的上下界,并采用一种改进的符号线性松弛方法减少了非线性节点边界计算过程中的过近似误差.通过计算节点过近似误差的直接和间接影响,将节点的约束进行细化,从而将原始验证问题划分为一组子问题,其混合整数规划(MILP)公式具有较少的约束数量.所提方法已实现为工具NNVerifier,并通过实验在经典的3个数据集上训练的4个基于ReLU的全连接基准网络进行性质验证和评估.实验结果表明,NNVerifier的验证效率比现有的完备验证技术提高了37.18%.

基于Transformer模型的文本自动摘要生成

论文探讨文本摘要的自动生成技术,其任务是产生能够表达文本主要含义的简明摘要。传统的Seq2Seq结构模型对长期特征和全局特征的捕获和存储能力有限,导致所生成的摘要中缺乏重要信息。因此,论文基于Transformer模型提出了一种新的生成式文本摘要模型RC-Transformer-PGN(RCTP)。该模型首先使用了一个附加的基于双向GRU的编码器来扩展Transformer模型,以捕获顺序上下文表示并提高局部信息的捕捉能力,其次引入指针生成网络以及覆盖机制缓解未登录词和重复词问题。在CNN/Daily Mail数据集上的实验结果表明论文模型与基线模型相比更具竞争力。

基于交互引导的问答对联合生成模型

大规模问答对的自动生成在知识问答库构建和机器阅读理解等许多应用具有关键价值.尽管其重要性已得到广泛认可,现有问答对生成方法仍面临着严峻挑战.首先,在传统的问答对生成模型中,抽取式的答案获取方法难以适用于复杂的自然交互场景.相比较而言,生成式模型通过对文本的语义理解,能够自动生成表述更加自然的答案.其次,对于问答对生成任务来说,为了防止生成的答案和问题出现语义上的不匹配,需要更全面地捕捉并增强答案生成和问题生成两个子任务之间的交互.最后,由于答案抽取和问题生成存在任务难度的差异,这两个任务在联合训练的过程中会出现任务之间的优化不平衡问题.为此,本文提出了一个基于交互引导的问答对联合生成模型(Interaction-Guided Joint Abstractive QAPs Generation Model,IGJA-QAP).具体而言,本文设计了一个带有答案引导的多头门机制的联合生成模型,同时对两个子任务进行统一建模并有效地捕获和增强它们之间的信息交互,从而可以生成语义上匹配的问答对.本文在三个大规模数据集SQuAD、NewQA和CoQA上进行了综合全面的实验分析.本文提出的模型在答案生成任务上METEOR值平均分别超出其他最佳方法3.0%、5.9%和4.3%,问题生成任务上METEOR值平均分别超出其他最佳方法1.5%、0.5%和2.1%.实验结果表明,本文提出的模型达到了目前最高的性能.

基于Abstract Factory模式的C#实现

随着面向对象设计技术的日益广泛运用,作为可复用技术基础的设计模式也得到了深入研究。本文结合C#语言,就创建模式中的AbstractFactory给出了一种可行的实现方式。

面向不可移动文物自然灾害风险图生成的领域特定语言

针对当前不可移动文物自然灾害风险图生成领域需求快速增长、经常变更,而现有程序及工具无法满足实际使用需要的问题,提出了一种构建语义模型的方法,在语义模型的基础之上,为不可移动文物领域专家设计了一种贴近自然语言的领域特定语言(DSL)。首先,通过对不可移动文物本体各项指标数据、风险图生成方法和流程进行深入研究,提取出业务模型。之后,通过分析业务模型,抽象出风险值计算规则的元计算单元,构建语义模型。在此基础之上,设计出一种可表述语义模型中所有语义的领域特定语言。该语言脚本可由领域专家自行编写,能快速高效地生成风险图,且易于扩展,满足需求经常变更的要求。与目前国内外主流的通过地理信息系统(GIS)方法生成风险图相比,利用DSL生成风险图可缩短66.7%以上的工作时长。

基于关键词异构图的生成式摘要研究

生成式摘要是自然语言处理中的重要任务,它帮助人们从海量文本中提取简洁而重要的信息.目前主流的生成式摘要模型是基于深度学习的序列到序列模型,这类模型生成的摘要质量更高.但由于缺乏对原文中关键词和句子之间的依赖关系的关注,现有模型生成的摘要仍然存在语义不明、重要信息含量低等问题.针对这个问题,提出了一种基于关键词异构图的生成式摘要模型.该模型通过从原始文本中提取关键词,将其与句子共同作为输入构建异构图,进而学习关键词和句子之间的依赖关系.文档编码器和图编码器分别用于学习文本知识和异构图中的依赖关系.此外,在解码器中采用分层图注意力机制来提高模型在生成摘要时对显著信息的关注.在CNN/Daily Mail和XSum数据集上进行了充分的实验,实验结果表明,所提模型在ROUGE评价指标上有了显著的提升.进一步的人类评估结果显示,所提模型所生成的摘要比基线模型包含更多的关键信息,并具有更高的可读性.

长文本摘要生成:基于Pegasus模型的STM32论文摘要生成分割策略研究

研究探讨了使用预训练的Pegasus模型进行长文本摘要时,不同文本分割方法对摘要质量的影响。收集来自知网的200篇关于STM32单片机的学术论文作为实验文本,比较了滑动窗口、句子分割、段落分割及滑动窗口加句子分割四种分割法的长文本摘要生成效果。实验使用ROUGE(Recall-Oriented Understudy for Gisting Evaluation)指标对生成的摘要进行评估,并对实验结果进行了详细分析。在生成摘要的质量方面,段落分割法表现出色,其ROUGE-1、ROUGE-2和ROUGE-L评分分别达到了30.85、7.60和20.15,轻微超过了句子分割法的评分,且显著优于句子分割加滑动窗口法。该研究旨在为研究者和开发者提供关于长文本摘要的实践经验和见解。

融合卷积收缩门控的生成式文本摘要方法

在深度学习技术的推动下,基于编码器-解码器架构并结合注意力机制的序列到序列模型成为文本摘要研究中应用最广泛的模型之一,尤其在生成式文本摘要任务中取得显著效果。然而,现有的采用循环神经网络的模型存在并行能力不足和时效低下的局限性,无法充分概括有用信息,忽视单词与句子间的联系,易产生冗余重复或语义不相关的摘要。为此,提出一种基于Transformer和卷积收缩门控的文本摘要方法。利用BERT作为编码器,提取不同层次的文本表征得到上下文编码,采用卷积收缩门控单元调整编码权重,强化全局相关性,去除无用信息的干扰,过滤后得到最终的编码输出,并通过设计基础Transformer解码模块、共享编码器的解码模块和采用生成式预训练Transformer(GPT)的解码模块3种不同的解码器,加强编码器与解码器的关联,以此探索能生成高质量摘要的模型结构。在LCSTS和CNNDM数据集上的实验结果表明,相比主流基准模型,设计的TCSG、ES-TCSG和GPT-TCSG模型的评价分数增量均不低于1.0,验证了该方法的有效性和可行性。

基于模块化Abstract-Refine算法框架的软件模型检测方法

Abstract-Refine(抽象—精炼)方法是软件模型检测领域中较为有效的设计思想,具有较高的通用性和效率优势,但目前并没有一个框架可以对其精确进行描述及实现有效的模块化使用和替换.本文提出了一种模块化的Abstract-Refine算法框架,分析和解释了Abstract-Refine算法所接受的输入程序的精细结构和特性,并对Abstract-Refine算法和相关子算法运用平衡操作符做以模块化解耦,使得子算法的修改和更换不需要依赖对上层的变更.经过实验验证,本方法可有效实现传统算法模块化解耦,同时不对原算法的性能造成冲击.

Verifying the accuracy of interlocking tables for railway signalling systems using abstract state machines

Railway transportation system is a critical sector where design methods and techniques are defined by international standards in order to reduce possible risks to an acceptable minimum level. CENELEC 50128 strongly recommends the utilization of finite state machines during system modelling stage and formal proof methods during the verifi- cation and testing stages of control algorithms. Due to the high importance of interlocking table at the design state of a sig- nalization system, the modelling and verification of inter- locking tables are examined in this work. For this purpose, abstract state machines are used as a modelling tool. The developed models have been performed in a generalized structure such that the model control can be done automatically for the interlocking systems. In this study, NuSMV is used at the verification state. Also, the consistency of the developed models has been supervised through fault injection. The developed models and software components are applied on a real railway station operated by Metro Istanbul Co.

A Contrastive Genre Analysis of English Abstract in Linguistic Journals Written by Chinese and English Writers

This paper contrastively studies the generic structures of sixty abstracts from English teaching and learning journals written by Chinese writers and English native writers.Analysis of the data is based on Swales' IMRD(Introduction-Method-Result-Discussion) model and all the data are coded through SPSS.Result indicates 1) English natives tend to write longer than Chinese.2) The rhetorical structure of the abstract tends to be more complete in the international journals.3) English natives tend to write more about the background details while the Chinese natives focus more on the result explanation.It is hoped that this comparison would shed some lights on abstract writing for Chinese writers.