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91.
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采用一种有别于传统嵌入式系统开发过程的新型开发方法:从概念到实现.以一个简单的乘法为例,利用Simulink、Embedded MATIAB、Real-Time Workshop等工具,在MATLAB平台上一次性完成从算法模型仿真到嵌入式代码生成的过程.之后在生成的代码中添加硬件接口并编译,经Proteus虚拟硬件测试... 相似文献
93.
在应变式火炮膛压测试仪中,直流不平衡电桥测量电路是测量火炮膛压信号的核心环节。由于电阻应变计阻值有一定的偏差,使得电桥在初始时达不到平衡,导致测试仪在没有应变时输出信号有为负值的可能性,致使测试仪所测得的数据无法以计算机数值校正方法实现。对于传统的机械电位器,手动调节的方法无法满足应变式火炮膛压测试仪封闭式、小体积的要求。本文设计的MSP430F2002单片机和MAX5402数字电位器所构成的电桥平衡自调节电路,具有结构简单、占用空间小、功耗低、可靠性高等特性,完全符合火炮膛压测试仪的要求。1电桥平衡自调节原理在火炮膛压测试仪中,考虑到测试仪壳体结构的限制以及低功耗的要求,采用的电桥为1/4直 相似文献
94.
Kung Chen Shu-Chun Weng Jia-Yin Lin Meng Wang Siau-Cheng Khoo 《Higher-Order and Symbolic Computation》2011,24(1-2):151-189
Many side-effecting programming activities, such as profiling and tracing, can be formulated as crosscutting concerns and be framed as side-effecting aspects in the aspect-oriented programming paradigm. The benefit gained from this separation of concerns is particularly evident in purely functional programming, as adding such aspects using techniques such as monadification will generally lead to crosscutting changes. This paper presents an approach to provide side-effecting aspects for lazy purely functional languages in a user transparent fashion. We propose a simple yet direct state manipulation construct for developing side-effecting aspects and devise a systematic monadification scheme to translate the woven code to monadic style purely functional code. Furthermore, we present a static and dynamic semantics of the aspect programs and reason about the correctness of our monadification scheme with respect to them. 相似文献
95.
针对户外复杂环境中的增强现实三维注册问题,提出一种基于随动控制的跟踪注册方法.所提出的方法通过惯性跟踪器实时获取角度跟踪数据,通过步进电机驱动高精度随动转台随动控制实景摄像机旋转,之后根据跟踪结果在虚实三维空间中建立摄像机模型,注册配准虚实摄像机的角度信息.所提出的随动控制使得跟踪器的误差不直接影响虚实叠加,降低了环境因素的影响.系统滞后和误差的实验数据分析表明所提出的方法提高了跟踪的稳定和精确性,在圆明园大水法遗址的实地应用结果证明了系统的实用性. 相似文献
96.
Yiliu Weng Xianlong Jin Zhijie Zhao Yuan Cao Jianwei Wang 《Simulation Modelling Practice and Theory》2010,18(6):752-767
Globalization and increasing market competition are forcing the automotive industry to develop technology that will enable more efficient collaboration between carmakers and their suppliers. One of the options that can meet this demand is to adopt grid technology in the collaboration process. For the system to be successfully applied, the trust relationship among Virtual Organization (VO) members becomes a very important factor. Systems lacking in secure mechanisms require all the collaborating members to fully trust each other, and thus make their application quite limited. Based on grid technology, this paper proposes a collaborative simulation system for vehicle crash safety design, and discusses the trust relationship among VO members. The grid middleware VEGA and web services working for the collaboration also contribute to the simulation system. Also, a test bed is set up on the basis of the Local Area Network (LAN). At the end of this paper, a real case involving a carmaker and a door supplier is presented to demonstrate how the grid-based collaborative simulation system works. 相似文献
97.
Wei-Chu Weng 《Advances in Engineering Software》2011,42(6):398-407
In this paper, we propose and implement a website of post-processing system for finite element analysis (WebDFEA). Finite element analysis is a computer-aided engineering tool and is popular for static/dynamic structure analysis. It includes three processing systems where post-processing system is to graphically demonstrate the analysis result of a structure model analyzed by finite element method. WebDFEA performs as a website. It is cross-platform because it can auto-detect a client computer platform and auto-download proper OpenGL API for drawing computer graphics. It can draw precise graphics on webpage which can be free controlled by the mouse as a manner in professional software. A database server is involved to store finite element model data and its analysis result. The graphic user interface (GUI) of WebDFEA is a flexible GUI comprising three parts: the switch buttons designed by HTML, the display board and the color bar both developed in Java. The three components are independent and cooperative with each other. They can be recombined without running errors for different purposes. A ship hull section with half a hatch is chosen as the study case to test WebDFEA website. Its finite element model comprises 11,442 triangle elements (shapes). The timeframe starting when WebDFEA is connected to the end when the model is demonstrated is acceptable. 相似文献
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99.
Effects of three‐dimensional virtual reality and traditional training methods on mental workload and training performance 下载免费PDF全文
Chin‐Jung Chao Sheng‐Yu Wu Yi‐Jan Yau Weng‐Yan Feng Feng‐Yi Tseng 《人机工程学与制造业中的人性因素》2017,27(4):187-196
Industries will implement effective training programs to improve training performance, and an ideal training performance occurs under proper mental workload (MWL). Virtual reality (VR) has recently been widely utilized in training; however, only a few studies have investigated its effects on MWL and training performance simultaneously. The purpose of this study is to investigate the effects of VR training and traditional training methods, such as technical manuals (TM) and multimedia films (MF), on training performance and MWL. The results of the performance measurement show that VR training is considered the best training method compared to TM and MF, particularly in the case of complex tasks. The results of physiological measurements (GSR [galvanic skin response], LF% [low frequency], and LF/HF [high frequency] ratio) show a significant difference between reading TM and using computer (MF and VR), wherein the latter has a lower MWL. However, no significant difference in subjective MWL assessment (NASA‐TLX [task load index]) and HF% measurement is found. 相似文献
100.
Yang Cheng-Hsing Weng Chi-Yao Lin Yih-Kai Liu Kuan-Liang 《Multimedia Tools and Applications》2017,76(22):23699-23720
Multimedia Tools and Applications - Reversible data hiding based on prediction methods is a data hiding technique wherein secret bits can be efficiently hidden into cover images. In this paper, we... 相似文献