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91.
陈慧南 《计算机工程与科学》2000,22(1):89-91
本文讨论基于扩充的着色网的事件驱动用户界面规范的实例问题。我们使用扩充的着色网作为对话模型表达互软件的人机交互行为。文中简述了扩充的着色网对话模型,给出 其对象一联系模型及核心算法,最后给出产将扩充的着色网表达的事件驱动用户界面规范转换成可视编程环境的语言程序的方法。 相似文献
92.
为了保证管理软件在整个生命周期内都具有可信性,在ICEMDA架构基础上融入可信性理论与方
法,提出了一种可信管理软件的模型驱动构造参考方法.通过分析国内外的研究现状,明确界定了管理软件
可信性概念,给出可信性判定问题描述.结果表明该方法以ICEMDA各层次上的构造体为中心,逐层进行可
信模型描述、可信指标度量、可信性判定与优化,借助ICEMDA的模型语义保持技术实现各层间可信性的保
持与传递,并以业务构件PSM模型的可信性判定为例简要介绍了该体系的具体实施机制 相似文献
93.
针对当前运行于不可预测开放环境下的嵌入式多使命复杂关键型系统,需要减少运行成本和处理不可预测工作负载情况的问题,文章提出一种混合关键度驱动的非对称式过载保护最小空闲调度策略。系统过载时,为共享同一处理器的不同关键度任务提供非对称式保护,禁止低关键度任务干扰高关键度任务,完全避免了传统的"关键度反转"问题。在恢复暂时阻塞的不同关键度任务时,在速率单调调度的基础上,引入关键度主导的截止期驱动动态调度策略,可使潜在处理器利用率达到100%。实验结果表明,这种新算法的综合性能优于当前已有的混合关键度任务调度算法。 相似文献
94.
Self‐adaptive software is a closed‐loop system, since it continuously monitors its context (i.e. environment) and/or self (i.e. software entities) in order to adapt itself properly to changes. We believe that representing adaptation goals explicitly and tracing them at run‐time are helpful in decision making for adaptation. While goal‐driven models are used in requirements engineering, they have not been utilized systematically yet for run‐time adaptation. To address this research gap, this article focuses on the deciding process in self‐adaptive software, and proposes the Goal‐Action‐Attribute Model (GAAM). An action selection mechanism, based on cooperative decision making, is also proposed that uses GAAM to select the appropriate adaptation action(s). The emphasis is on building a light‐weight and scalable run‐time model which needs less design and tuning effort comparing with a typical rule‐based approach. The GAAM and action selection mechanism are evaluated using a set of experiments on a simulated multi‐tier enterprise application, and two sample ordinal and cardinal action preference lists. The evaluation is accomplished based on a systematic design of experiment and a detailed statistical analysis in order to investigate several research questions. The findings are promising, considering the obtained results, and other impacts of the approach on engineering self‐adaptive software. Although, one case study is not enough to generalize the findings, and the proposed mechanism does not always outperform a typical rule‐based approach, less effort, scalability, and flexibility of GAAM are remarkable. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
95.
Engineer Bainomugisha Jorge Vallejos Elisa Gonzalez Boix Pascal Costanza Theo D'Hondt Wolfgang De Meuter 《Software》2012,42(3):331-356
The iPhone SDK provides a powerful platform for the development of applications that make use of iPhone capabilities, such as sensors, GPS, Wi‐Fi, or Bluetooth connectivity. We observe that so far the development of iPhone applications has mostly been restricted to using Objective‐C. However, developing applications in plain Objective‐C on the iPhone OS suffers from limitations, such as the need for explicit memory management and lack of syntactic extension mechanism. Moreover, when developing distributed applications in Objective‐C, programmers have to manually deal with distribution concerns, such as service discovery, remote communication, and failure handling. In this paper, we discuss our experience in porting the Scheme programming language to the iPhone OS and how it can be used together with Objective‐C to develop iPhone applications. To support the interaction between Scheme programs and the underlying iPhone APIs, we have implemented a language symbiosis layer that enables programmers to access the iPhone SDK libraries from Scheme. In addition, we have designed high‐level distribution constructs to ease the development of distributed iPhone applications in an event‐driven style. We validate and discuss these constructs with a series of examples, including an iPod controller, a maps application, and a distributed multiplayer Scrabble‐like game. We discuss the lessons learned from this experience for other programming language ports to mobile platforms. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
96.
Design patterns codify proven solutions to recurring design problems. Their proper use within a development context requires that: (i) we understand them; (ii) we ascertain their applicability or relevance to the design problem at hand; and (iii) we apply them faithfully to the problem at hand. We argue that an explicit representation of the design problem solved by a design pattern is key to supporting the three tasks in an integrated fashion. We propose a model‐driven representation of design patterns consisting of triples < MP, MS, T > where MP is a model of the problem solved by the pattern, MS is a model of the solution proposed by the pattern, and T is a model transformation of an instance of the problem into an instance of the solution. Given an object‐oriented design model, we look for model fragments that match MP (call them instances of MP), and when one is found, we apply the transformation T yielding an instance of MS. Easier said than done. Experimentation with an Eclipse Modeling Framework‐based implementation of our approach applied to a number of open‐source software application's raised fundamental questions about: (i) the nature of design patterns in general, and the ones that lend themselves to our approach, and (ii) our understanding and codification of seemingly simple design patterns. In this paper, we present the principles behind our approach, report on the results of applying the approach to the Gang of Four (GoF) design patterns, and discuss the representability of design problems solved by these patterns. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
97.
A new dimmer using a mental-oxide-semiconductor field-effect transistor (MOSFET) for alternating-current (AC) directly driven
light-emitting-diode (LED) lamp was presented. The control method of proposed dimmer is pulse width control (PWM) method.
Compared with the conventional phase-controlled dimmer, the proposed PWM dimmer can produce sine wave and did not cause harmonics
problem. Furthermore, the proposed control method did not amplify the light flicker due to the independence of input voltage.
Therefore, the PWM dimmer can be used as the dimmer of the AC LED lamp instead of the conventional phase-controlled dimmer.
The experimental result shows that the proposed PWM dimmer has good performances. 相似文献
98.
宋亚军 《河南机电高等专科学校学报》2013,(1):83-86
词汇学习是英语学习的重要组成部分,但词汇学习问题依然是教师和学生面对的棘手问题。文章主要探讨了依靠多媒体手段下的语料库数据驱动方法和建构主义学习理论相结合的学生自主学习能力的培养模式,实践表明这种模式在培养学生学习兴趣和提高学生词汇能力方面的确有积极作用。 相似文献
99.
100.
随着现代工业过程的不断发展,自动化设备越来越复杂。系统的安全性与可靠性是设备现代化的重要方面。数据驱动的故障诊断技术是复杂工业生产过程安全性与可靠性的重要保障之一。传统的Fisher判别分析方法:常常忽视了量纲在各过程变量特征提取过程中的影响。本文在回顾传统Fisher判别分析理论的基础上,指出了量纲及量纲标准化过程对判别分析过程产生的影响,并建立了一种相对Fisher判别分析方法:。先通过预处理的方法:消除量纲差异带来的虚假影响,然后根据系统要求对观测数据做相对化变换,从而更有效地获取各观测数据的代表信息及不同运行模式的判断阈值。最后,利用计算机仿真实验验证了本文方法:的有效性。 相似文献