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991.
This paper discusses the design of materials that utilize embedded computational techniques to demonstrate the capacity to learn, adapt and develop responsive behaviors that are shaped over time. The focus is on materials that develop time-based relationships based on a level of ‘experience’ they accumulate from long-term interaction with their users and environment. Materials with ‘computational experience’ are demonstrated with two designs: an interactive rocking chair that utilizes its material properties and computational abilities to manage its own energy production and consumption while providing physical and mental exercises to its user; and an LED-based, reconfigurable display that adjusts its content based on its interaction with its user while monitoring its internal conditions, environmental factors and usage. These examples are used to discuss the design of computational ‘styles’ for materials that would not only allow them to express signature characteristics embedded in their physical properties and computational behavior but also function as features that would evolve in response to interaction patterns and accumulated experiences. Throughout the paper, behavior-driven material practices are presented and their potential to influence the look, feel and functionalities of products and spaces are discussed.  相似文献   
992.
Space crews are in need for excellent cognitive support to perform nominal and off-nominal actions. This paper presents a coherent cognitive engineering methodology for the design of such support, which may be used to establish adequate usability, context-specific support that is integrated into astronaut’s task performance and/or electronic partners who enhance human–machine team’s resilience. It comprises (a) usability guidelines, measures and methods, (b) a general process guide that integrates task procedure design into user interface design and a software framework to implement such support and (c) theories, methods and tools to analyse, model and test future human–machine collaborations in space. In empirical studies, the knowledge base and tools for crew support are continuously being extended, refined and maintained.  相似文献   
993.
Along with the improvement of the key technologies for pervasive computing, the design of applications itself has emerged as a notable research area. A design should decide which features go into the application of supporting its context-awareness and ascertaining how well those features add value for users with an acceptable user experience. This paper initially identifies the challenges in designing and evaluating pervasive applications. It then presents a condensed survey of prototyping techniques and existing toolkits with the aim of understanding how the design issues have been addressed by research prototypes. At the end, we describe various open issues with suggestions of possible ways to extend the capabilities of current prototyping toolkits.  相似文献   
994.
Structural optimization with frequency constraints is highly nonlinear dynamic optimization problems. Genetic algorithm (GA) has greater advantage in global optimization for nonlinear problem than optimality criteria and mathematical programming methods, but it needs more computational time and numerous eigenvalue reanalysis. To speed up the design process, an adaptive eigenvalue reanalysis method for GA-based structural optimization is presented. This reanalysis technique is derived primarily on the Kirsch’s combined approximations method, which is also highly accurate for case of repeated eigenvalues problem. The required number of basis vectors at every generation is adaptively determined and the rules for selecting initial number of basis vectors are given. Numerical examples of truss design are presented to validate the reanalysis-based frequency optimization. The results demonstrate that the adaptive eigenvalue reanalysis affects very slightly the accuracy of the optimal solutions and significantly reduces the computational time involved in the design process of large-scale structures.  相似文献   
995.
Connectivity is very important to enable ubiquitous computing. Wireless communication plays a continual key role in future ubiquitous network where all devices need to be connected freely. Ultra-wideband (UWB) radio is a new method of short-range wireless technology which is suit for ubiquitous computing. In this paper, we provided the potentials of impulse radio UWB (IR-UWB) technology in ubiquitous computing environments. Our study investigated possible communication methods which can be used in ubiquitous network. Comparisons between different communication technologies demonstrated that UWB-based solutions can support identification, location, sensing, and connectivity. In addition, we proposed two typical schemes which show how IR-UWB is used in ubiquitous computing.  相似文献   
996.
采用瞬变电磁法勘探到的信号中包含大量的强干扰信号,如不剔除强干扰信号,反演得到的计算结果误差较大。针对该问题,提出了一种基于LabVIEW的瞬变电磁数据采集及预处理系统的设计方案。该系统采用数据采集卡USB2089采集二次涡流场信号,并将其转换为计算机能处理的数字信号,然后通过LabVIEW平台的功能流程、功能算法剔除数字信号中的强干扰信号,从而实现对瞬变电磁数据的有效采集。仿真结果表明,该系统可剔除瞬变电磁数据中的强干扰信号,保证了数据采集的准确性。  相似文献   
997.
基于GA算法的无线躯体传感网络的自适应优化研究   总被引:1,自引:0,他引:1  
将无线躯体传感网络技术结合到井下异常时的人员搜救系统中,在井下出现异常时,实现人员位置信息与生理状况信息的采集,有助于营救人员制定高效的营救方案,从而显著提高井下人员搜救水平;将遗传算法应用于井下无线传感网络的多目标优化设计,设计了井下网络的组网策略,制定了适当的编码机制,并结合多方面重要参数,建立了适应度函数;通过MATLAB仿真表明了基于遗传算法的网络设计能够很好地优化能量管理,并使网络生命周期达到最长。  相似文献   
998.
针对网域内简单背景下目标感知识别处理速度慢、准确率低的问题,提出了基于最优算法组合的目标检测方法;该方法将多种图像处理方法融入目标识别算法中,在采用不同算法对采集到的图像进行预处理、分割和特征提取效果比较的基础上,确定出最优算法组合并设计实验验证其可靠性和鲁棒性;试验结果表明该方法能够快速有效的判别行人目标,识别率达到96.67%,解决了网域内目标检测问题;与其他单一算法相比具有处理速度更快、判别更加有效,实时性高等特点,明显优于一般算法。  相似文献   
999.
为了保证冷库内货物质量、维持其最佳储藏环境、提高冷库自动化水平,设计了一款冷库智能监控系统;系统以LPC2103为核心,利用传感器、信号调理电路进行数据采集,并结合软件实现对冷库环境参数的控制;分布式采样点的硬件布局克服了冷库环境参数不均匀,波动性大的缺陷,通过软件滤波算法与智能控制方法进一步屏蔽了信号传输的干扰,为控制设备提供了准确的指令;对温度参数进行记录与分析的实验结果表明,系统误差小并能够准确、及时的调节环境,因此系统结构简单,运行稳定,调控方便,能够有效保证储藏货物质量.  相似文献   
1000.
随着现代被测对象复杂性的增加以及单一接口形式测试总线产品种类的限制,大多情况下必须要构建多总线平台一体化测试系统;然而不同接口形式的测试设备时钟同步和触发机制不同,多总线平台一体化过程中时钟同步和触发的统一是必须要考虑的问题;在提出了基于硬线的方式、基于PTP的方式以及混合方式三种时钟同步和触发设计的同时,以在研项目硬件设备为平台,对其性能进行了测试;结果显示,方案不同同步精度不同,基于硬线和PTP的方式最大同步偏差分别为50ns和523ns,可适用于不同的测试场景.  相似文献   
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