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31.
在电磁驱动原理的基础上,设计并研制了一种磁能驱动的微型泵。微型泵的整体尺寸约为Φ11mm×4mm,腔室半径为5mm,深2mm。利用方差分析方法对实验数据进行了检验,验证了前期微型泵研究中获得的性能参数的正确性。为了进一步缩小微型泵体积、简化控制方式和外围电路,针对微型泵的能源部分,开展了单双电源的对比实验研究,并获得了较好的实验结果。  相似文献   
32.
案例—任务驱动模式的计算机程序语言教学探究   总被引:2,自引:0,他引:2  
案例—任务驱动式教学是将案例和任务驱动教学有机结合的一种新教学方法,该方法目前在计算机程序语言教学中正处于探索和尝试阶段。本文针对传统计算机程序语言教学的不足,分析研究了案例—任务驱动式教学运用于计算机程序语言课程教学的可行性和实施策略,形成了计算机程序语言案例—任务驱动教学模式。  相似文献   
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Driven by the emergence of mobile and pervasive computing there is a growing demand for context‐aware software systems that can dynamically adapt to their run‐time environment. We present the results of project MADAM that has delivered a comprehensive solution for the development and operation of context‐aware, self‐adaptive applications. The main contributions of MADAM are (a) a sophisticated middleware that supports the dynamic adaptation of component‐based applications, and (b) an innovative model‐driven development methodology that is based on abstract adaptation models and corresponding model‐to‐code transformations. MADAM has demonstrated the viability of a general, integrated approach to application‐level adaptation. We discuss our experiences with two real‐world case studies that were built using the MADAM approach. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
35.
乔得吉  肖卫东 《计算机科学》2016,43(Z6):489-492
出于信息安全和业务需要,人们在彼此逻辑或物理隔离的局域网环境中浏览和处理信息,但是又不想丧失网络互联带来的便利和强大的信息处理能力。通过数据传输与同步机制,模拟广域网环境、避免信息孤岛是一种现实可行的选择。给出了一种基于XML的任务驱动的数据传输与同步方法,通过分析数据传输场景,设定了基于XML的任务数据模板和任务结果数据模板,借助于具体的信息化系统,基于相应的模板,自动生成任务数据包及任务数据结果包,以数据光盘进行信息传输,通过数据寻址、定位及导入操作实现了数据同步功能。通过该数据通路,实现了各级彼此独立的信息系统的互联,用户犹如在一个互联的广域网环境中进行数据处理。该方法大大提升了信息系统的安全性,降低了铺设或租用线路的成本,解决了各级网络之间不连通导致的信息壁垒,更符合现阶段特殊行业使用网络环境的要求。  相似文献   
36.
In this work, a method for fast design optimization of broadband antennas is considered. The approach is based on a feature‐based optimization (FBO) concept where reflection characteristics of the structure at hand are formulated in terms of suitably defined feature points. Redefinition of the design problem allows for reducing the design optimization cost, because the dependence of feature point coordinates on antenna dimensions is less nonlinear than for the original frequency characteristics (here, S‐parameters). This results in faster convergence of the optimization algorithm. The cost of the design process is further reduced using variable‐fidelity electromagnetic (EM) simulation models. In case of UWB antennas, the feature points are defined, among others, as the levels of the reflection characteristic at its local in‐band maxima, as well as location of the frequency point which corresponds to acceptable reflection around the lower corner frequency within the UWB band. Also, the number of characteristic points depends on antenna topology and its dimensions. Performance of FBO‐based design optimization is demonstrated using two examples of planar UWB antennas. Moreover, the computational cost of the approach is compared with conventional optimization driven by a pattern search algorithm. Experimental validation of the numerical results is also provided.  相似文献   
37.
Human activity recognition is an effective approach for identifying the characteristics of historical data. In the past decades, different shallow classifiers and handcrafted features were used to identify the activities from the sensor data. These approaches are configured for offline processing and are not suitable for sequential data. This article proposes an adaptive framework for human activity recognition using a deep learning mechanism. This deep learning approach forms the deep belief network (DBN), which contains a visible layer and hidden layers. The processing of raw sensor data is performed by these layers and the activity is identified at the top most layers. The DBN is tested using the real time environment with the help of mobile devices that contain an accelerometer, a magnetometer, and a gyroscope. The results are analyzed with the metrics of precision, recall, and the F1-score. The results proved that the proposed method has a higher F1_score when compared to the existing approach.  相似文献   
38.
To allow efficient and user‐friendly development of a component‐based application, component systems have to provide a rather complex development infrastructure, including a tool for component composition, component repository, and a run‐time infrastructure. In this paper, we present and evaluate benefits of using meta‐modeling during the process of defining a component system and also during creation of the development and run‐time infrastructures. Most of the presented arguments are based on a broad practical experience with designing the component systems SOFA and SOFA 2; the former designed in a classical ad hoc ‘manual’ way, whereas the latter with the help of meta‐modeling. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
39.
"任务驱动法"是建立在建构主义教学理论基础上的教学法,作为建构者——教师,仅是学习的指导者、辅助者、咨询者、导航者,而学生才是教与学活动中的主体,在具体教学过程中,我们应将大量时间留给学生带着驱动"任务"进行研究性学习。目前,我国中学信息技术课程中普遍采用这一教学法,即在具体教学过程中,我们应尽量压缩教师讲授内容的时间,而将大量的时间留给学生进行研究性学习。本文就如何优化信息技术课程谈几点思考。  相似文献   
40.
Test-driven development (TDD) is a software development practice that has been used sporadically for decades. With this practice, a software engineer cycles minute-by-minute between writing failing unit tests and writing implementation code to pass those tests. Test-driven development has recently re-emerged as a critical enabling practice of agile software development methodologies. However, little empirical evidence supports or refutes the utility of this practice in an industrial context. Case studies were conducted with three development teams at Microsoft and one at IBM that have adopted TDD. The results of the case studies indicate that the pre-release defect density of the four products decreased between 40% and 90% relative to similar projects that did not use the TDD practice. Subjectively, the teams experienced a 15–35% increase in initial development time after adopting TDD.
Laurie WilliamsEmail:

Nachiappan Nagappan   is a researcher in the Software Reliability Research group at Microsoft Research. He received his MS and PhD from North Carolina State University in 2002 and 2005, respectively. His research interests are in software reliability, software measurement and empirical software engineering. Dr. E. Michael Maximilien   (aka “max”) is a research staff member at IBM’s Almaden Research Center in San Jose, California. Prior to joining ARC, he spent ten years at IBM’s Research Triangle Park, N.C., in software development and architecture. He led various small- to medium-sized teams, designing and developing enterprise and embedded Java™ software; he is a founding member and contributor to three worldwide Java and UML industry standards. His primary research interests lie in distributed systems and software engineering, especially Web services and APIs, mashups, Web 2.0, SOA (service-oriented architecture), and Agile methods and practices. He can be reached through his Web site (maximilien.org) and blog (blog.maximilien.com). Thirumalesh Bhat   is a Development Manager at Microsoft Corporation. He has worked on several versions of Windows and other commercial software systems at Microsoft. He is interested in software reliability, testing, metrics and software processes. Laurie Williams   is an associate professor of computer science at North Carolina State University. She teaches software engineering and software reliability and testing. Prior to joining NCSU, she worked at IBM for nine years, including several years as a manager of a software testing department and as a project manager for a large software project. She was one of the founders of the XP Universe conference in 2001, the first US-based conference on agile software development. She is also the lead author of the Pair Programming Illuminated book and a co-editor of the Extreme Programming Perspectives book.   相似文献   
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