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981.
E. M. Lavrishcheva 《Cybernetics and Systems Analysis》2008,44(3):324-332
A new interpretation of software engineering from scientific, engineering, and practical standpoints is proposed. Software
engineering is defined as a successor of programming and computer science, namely, its management theory. Features and attributes
of software engineering as an original discipline are founded. The structure, content, and concepts of this discipline and
its basic elements are presented.
__________
Translated from Kibernetika i Sistemnyi Analiz, No. 3, pp. 19–28, May–June 2008. 相似文献
982.
Richard A. Foulds David M. Saxe Arthur W. JoyceIII Sergei Adamovich 《Virtual Reality》2008,12(2):87-97
The sensory-motor skills of persons with neuromuscular disabilities have been shown to be enhanced by intensive and repetitive
therapeutic interventions. This paper describes a form of low immersion virtual reality and a prototype, open source system
that allow a user with significant physical disability to actively interact with computer-generated objects whose behaviors
promote a game-like interaction. Unlike fully immersive and haptic virtual reality, this approach frees the user from head-mounted
displays and gloves. It extracts the user’s real-time silhouette from the output of a remote video camera and uses that two-dimensional
outline to interact with graphical objects on screen. In contrast to video games that have been modified with specialized
interfaces, this virtual interaction system promotes the repetitive use of goal directed movements of the arms and body, which
are essential to promote cortical reorganization, as well as discourage unwanted changes in muscle tissue that result in contracture.
A prototype system demonstrates the potential of low immersion technology to motivate users and encourage participation in
therapy. It also offers the potential of accommodating the sensory-motor skills of individuals with very significant impairment.
The behaviors of the computer-generated graphics can be altered to allow use by those with very limited range of motion and/or
motor control. These behaviors can be adjusted to provide a continuing challenge as the user’s skills improve. This prototype
is described in terms of functional capabilities that include a silhouette extraction from a video image, and generation of
graphical objects that interact with the silhouette. The work is extended with a discussion of a more sophisticated region
of interest detection algorithm that can select specific parts of the body. 相似文献
983.
Eric Bouwers Martin Bravenboer Eelco Visser 《Electronic Notes in Theoretical Computer Science》2008,203(2):85
A wide range of parser generators are used to generate parsers for programming languages. The grammar formalisms that come with parser generators provide different approaches for defining operator precedence. Some generators (e.g. YACC) support precedence declarations, others require the grammar to be unambiguous, thus encoding the precedence rules. Even if the grammar formalism provides precedence rules, a particular grammar might not use it. The result is grammar variants implementing the same language. For the C language, the GNU Compiler uses YACC with precedence rules, the C-Transformers uses SDF without priorities, while the SDF library does use priorities. For PHP, Zend uses YACC with precedence rules, whereas PHP-front uses SDF with priority and associativity declarations.The variance between grammars raises the question if the precedence rules of one grammar are compatible with those of another. This is usually not obvious, since some languages have complex precedence rules. Also, for some parser generators the semantics of precedence rules is defined operationally, which makes it hard to reason about their effect on the defined language. We present a method and tool for comparing the precedence rules of different grammars and parser generators. Although it is undecidable whether two grammars define the same language, this tool provides support for comparing and recovering precedence rules, which is especially useful for reliable migration of a grammar from one grammar formalism to another. We evaluate our method by the application to non-trivial mainstream programming languages, such as PHP and C. 相似文献
984.
Modeling and verification of a telecommunication application using live sequence charts and the Play-Engine tool 总被引:1,自引:0,他引:1
We apply the scenario-based approach to modeling, via the language of live sequence charts (LSCs) and the Play-Engine tool
to a real-world complex telecommunication service, . It allows a user to call for help from a doctor, the fire brigade, a car maintenance service, etc. These kinds of services
are built on top of an embedded platform, using both new and existing service components, and their complexity stems from
their distributed architecture, the various time constraints they entail, and their rapidly evolving underlying systems. A
well known problem in this class of telecommunication applications is that of feature interaction, whereby a new feature might
cause problems in the execution of existing features. Our approach provides a methodology for high-level modeling of telecommunication
applications that can help in detecting feature interaction at early development stages. We exhibit the results of applying
the methodology to the specification, animation and formal verification of the Depannage service.
相似文献
Hillel Kugler (Corresponding author)Email: |
985.
Martin Ebner Michael Kickmeier-Rust Andreas Holzinger 《Universal Access in the Information Society》2008,7(4):199-207
Wikis are a website technology for mass collaborative authoring. Today, wikis are increasingly used for educational purposes.
Basically, the most important asset of wikis is free and easy access for end users: everybody can contribute, comment and
edit—following the principles of Universal access. Consequently, wikis are ideally suited for collaborative learning and a
number of studies reported a great success of wikis in terms of active participation, collaboration, and a rapidly growing
content. However, the wikis success in education was often linked either to direct incentives or even pressure. This paper
strongly argues that this contradicts the original intentions of wikis and, furthermore, weakens the psycho-pedagogical impact.
A study is presented which focuses on investigating the success of wikis in higher education, when students are neither enforced to contribute nor directly rewarded similar to the principles of Wikipedia. Amazingly, the results show that, in total, none of the N = 287 students created new articles or edited existing ones during a whole semester. It is concluded that the use of Wiki-Systems
in educational settings is much more complicated, and it needs more time to develop a kind of “give-and-take” generation. 相似文献
986.
This paper contextualises, describes and discusses a student project which takes a particular exploratory approach to using
mathematical surface definition as a language and vehicle for co-rational design co-authorship for architecture and engineering.
The project has two authors, one from an architectural and one from an engineering educational background. It investigates
the metaphorical and operational role of mathematics in the design process and outcomes. 相似文献
987.
煤矿井下无线传感网络通信关键技术的研究 总被引:4,自引:0,他引:4
煤矿井下环境监测是无线传感网络的应用之一,要求监测数据必须通过土壤、煤岩传输,这给无线通信技术提出了新的挑战。文章分析了煤矿井下无线传感网络通信技术面临的问题,证明了井下信道特性与土壤、煤岩特性,特别是与湿度相关。为降低能耗、克服高损耗,文章在分析了陆地无线传感网络的通信协议的基础上,对无线传感网络的通信协议提出了修改建议。此外,为提高网络效率和可靠性,提出了跨层管理协议的设计方法。 相似文献
988.
989.
Luiz Marcio Cysneiros Julio Cesar Sampaio do Prado Leite Jaime de Melo Sabat Neto 《Requirements Engineering》2001,6(2):97-115
The development of complex information systems calls for conceptual models that describe aspects beyond entities and activities.
In particular, recent research has pointed out that conceptual models need to model goals, in order to capture the intentions
which underlie complex situations within an organisational context. This paper focuses on one class of goals, namely non-functional
requirements (NFR), which need to be captured and analysed from the very early phases of the software development process.
The paper presents a framework for integrating NFRs into the ER and OO models. This framework has been validated by two case
studies, one of which is very large. The results of the case studies suggest that goal modelling during early phases can lead
to a more productive and complete modelling activity. 相似文献
990.
Clarisse Sieckenius de Souza Simone Diniz Junqueira Barbosa Raquel Oliveira Prates 《Knowledge》2001,14(8):461-465
Designing software involves good perception, good reasoning, and a talent to express oneself effectively through programming and interactive languages. Semiotic theories can help HCI designers increase their power to perceive, reason and communicate. By presenting some of the results we have reached with semiotic engineering over the last few years, we suggest that the main contributions of semiotic theory in supporting HCI design are: to provide designers with new perceptions on the process and product of HCI design; to bind together all the stages of software development and use, giving them a unique homogeneous treatment; and to pose innovative questions that extend the frontiers of HCI investigations. 相似文献