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991.
计算机应用技术促进了流程工业的变革和发展,并日益渗透到流程工业的各个方面。文章以流程工业中的化工行业为重点,论述了计算机在流程工业自动控制、故障诊断与检测、软测量等领域的应用原理与方法,阐明了计算机是提高企业自动化和信息化水平的关键,阐述了化工流程工业中计算机的应用技术发展所面临的问题并就其发展提出若干建议。 相似文献
992.
Defining the meaning of tabular mathematical expressions 总被引:2,自引:0,他引:2
Ying Jin 《Science of Computer Programming》2010,75(11):980-1000
Mathematical expressions in tabular form (also called “tabular expressions” or “tables”) have been shown to be useful for documenting and analysing software systems. They are usually easier to read than conventional mathematical expressions but are no less precise. They can be used wherever mathematical expressions are used. To avoid misunderstandings, and to support users with trustworthy tools, the meaning of these expressions must be fully defined.This paper presents a new method for defining the meaning of tabular expressions. Each definition of an expression type names the expression’s constituents, and provides a restriction schema and one or more evaluation schemas. The restriction schema defines the class of well-formed expressions of the type. An evaluation schema maps a well-formed tabular expression of the type to a mathematical expression of a previously defined type. Since the meaning of conventional mathematical expressions is well known, describing an equivalent expression fully defines the meaning of a tabular expression.In this approach, indexation is used to decouple the appearance of a tabular expression from its semantics. A tabular expression is an indexed set of grids; a grid is an indexed set of expressions. The expressions in a grid can be either conventional expressions or tabular expressions of a previously defined type.Defining the meaning of a tabular expression in this way facilitates the building of tools that faithfully implement the semantics. The decoupling of syntax and semantics by means of indices overcomes some limitations of older approaches.The method presented in the paper is illustrated by defining several previously known types of tabular expressions and some new ones. The use of the new model to build a suite of tools for the input, presentation, validation, evaluation, simplification, conversion and composition of tabular expressions is discussed. 相似文献
993.
Jeff Winter Author Vitae Kari Rönkkö Author Vitae 《Journal of Systems and Software》2010,83(11):2059-2072
This article presents an experience report where we compare 8 years of experience of product related usability testing and evaluation with principles for software process improvement (SPI). In theory the product and the process views are often seen to be complementary, but studies of industry have demonstrated the opposite. Therefore, more empirical studies are needed to understand and improve the present situation. We find areas of close agreement as well as areas where our work illuminates new characteristics. It has been identified that successful SPI is dependent upon being successfully combined with a business orientation. Usability and business orientation also have strong connections although this has not been extensively addressed in SPI publications. Reasons for this could be that usability focuses on product metrics whilst today's SPI mainly focuses on process metrics. Also because today's SPI is dominated by striving towards a standardized, controllable, and predictable software engineering process; whilst successful usability efforts in organisations are more about creating a creative organisational culture advocating a useful product throughout the development and product life cycle. We provide a study and discussion that supports future development when combining usability and product focus with SPI, in particular if these efforts are related to usability process improvement efforts. 相似文献
994.
Bettina Biel Author Vitae Volker Gruhn Author Vitae 《Journal of Systems and Software》2010,83(11):2031-2044
Designing easy to use mobile applications is a difficult task. In order to optimize the development of a usable mobile application, it is necessary to consider the mobile usage context for the design and the evaluation of the user-system interaction of a mobile application. In our research we designed a method that aligns the inspection method “Software ArchitecTure analysis of Usability Requirements realizatioN” SATURN and a mobile usability evaluation in the form of a user test. We propose to use mobile context factors and thus requirements as a common basis for both inspection and user test. After conducting both analysis and user test, the results described as usability problems are mapped and discussed. The mobile context factors identified define and describe the usage context of a mobile application. We exemplify and apply our approach in a case study. This allows us to show how our method can be used to identify more usability problems than with each method separately. Additionally, we could confirm the validity and identified the severity of usability problems found by both methods. Our work presents how a combination of both methods allows to address usability issues in a more holistic way. We argue that the increased quantity and quality of results can lead to a reduction of the number of iterations required in early stages of an iterative software development process. 相似文献
995.
996.
Recent developments in computing and mobile technologies have enabled the mobile and ubiquitous learning approach, which situates students in an environment that combines real-world and digital-world learning resources. Although such an approach seems to be innovative and interesting, several problems have been revealed when applying it to practical learning activities. One major problem is owing to the lack of proper learning strategies or tools that can guide or assist the students to learn in such a complex learning scenario. Students might feel excited or interested when using the mobile devices to learn in the real world; however, their learning achievements could be disappointing. To cope with this problem, in this study, a knowledge engineering approach is proposed to develop Mindtools for such innovative learning scenarios. Experimental results from a natural science course of an elementary school show that this innovative approach not only enhances learning motivation, but also improves the learning achievements of the students. 相似文献
997.
基于工学结合的网络综合布线教学改革实践 总被引:1,自引:0,他引:1
钟达夫 《数字社区&智能家居》2010,(6):1348-1349
该文阐述了网络综合布线在课程体系的作用,提出了工学结合的教学设计和教学方法,最后给出教学改革产生的教学效果。 相似文献
998.
该文将模糊集的相关理论应用到软件可靠性评价上面,取得了较好的评价效果。论文首先介绍了模糊集的相关理论,利用在软件工程中具有一定模糊度的“软件可靠性”的概念对软件可靠性评价方法进行了论述。该方法无论是理论上,还是在软件可靠性评价中的应用方面,都充分体现了模糊集的特殊价值,并值得计算机软件人员在今后进行较为深入的研究。 相似文献
999.
该文围绕培养应用型人才,突出应用能力培养这个目标出发,从教学内容、教学组织和方法、实践环节、能力培养四个方面进行网络安全课程教学改革探讨。 相似文献
1000.
李霞婷 《数字社区&智能家居》2010,(8)
我院经过多年的努力与改革,不断完善值班管理系统功能,并取得了初步的成效。该文结合我院实际情况,从建设原则、设计实施、运行情况及解决方案等几个方面,分析了我院值班管理系统建设中需要解决的一些问题和一些开发心得。 相似文献