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91.
A multimedia presentation is a synchronized, and possibly interactive, delivery of multimedia data to users. We expect that, in the future, multimedia presentations will be stored into and queried from multimedia databases. In an earlier work, we have designed a graphical query language, called GVISUAL, that allows users to query multimedia presentations based on content information. In this paper, we discuss GVISUAL query processing techniques for multimedia presentations. More specifically, we discuss the translation of GVISUAL queries into an operator-based language, called O-Algebra, with three new operators, and efficient implementations of the new O-Algebra operators using a coding system called nodecodes.  相似文献   
92.
High throughput biological data need to be processed, analyzed, and interpreted to address problems in life sciences. Bioinformatics, computational biology, and systems biology deal with biological problems using computational methods. Clustering is one of the methods used to gain insight into biological processes, particularly at the genomics level. Clearly, clustering can be used in many areas of biological data analysis. However, this paper presents a review of the current clustering algorithms designed especially for analyzing gene expression data. It is also intended to introduce one of the main problems in bioinformatics – clustering gene expression data – to the operations research community.  相似文献   
93.
The main purpose of this study was to investigate the views of primary students about interactive whiteboard [IWB] use in their classes from attitudinal and pedagogical perspectives. Research was designed as an empirical approach to phenomenology. Data was collected from fifty primary students (fourth to eighth) through focus group interviews. Nvivo 9 qualitative data analysis software was used to analyze data. Results showed that students like instruction with IWB especially for such reasons/capabilities as practical and economical use, better visual presentation, and test-based use. Students were predominantly uncomfortable with the technical problems. They believed that instruction with IWB positively impacted their learning especially because of visualization and contextualization, effective presentation, test-based use, and motivational factors. Finally it was inferred that IWBs were not used to their full potential, and both technical problems and common practices indicated that teachers were still at an initial stage of transmission to instruction with IWB and they needed both technical and pedagogical training.  相似文献   
94.
This paper considers the problem of multirobot coordination in pick-and-place tasks on a conveyor band. The robot team is composed of identical robots with mutually exclusive, but neighboring workspaces. The products are fed in at one end of the band, move through each workspace sequentially until being picked up and are collected at the other end—if not picked up interim. Each robot has the same task—that is picking up and packaging as many products as possible. We propose an approach based on noncooperative game theory where each robot uses local observations of the conveyor band and their neighbors' actions in order to decide on its actions. The developed algorithm has been implemented and tested in a simulated manufacturing environment using Webots. Results obtained from the simulations are analyzed using a variety of statistical performance measures.  相似文献   
95.
Multiscale modeling and integration of physiological models carry challenges due to the complex nature of physiological processes. High coupling within and among scales present a significant challenge in constructing and integrating multiscale physiological models. In order to deal with such challenges in a systematic way, there is a significant need for an information technology framework together with related analytical and computational tools that will facilitate integration of models and simulations of complex biological systems. Physiological Model Simulation, Integration and Modeling Framework (Phy-SIM) is an information technology framework providing the tools to facilitate development, integration and simulation of integrated models of human physiology. Phy-SIM brings software level solutions to the challenges raised by the complex nature of physiological systems. The aim of Phy-SIM, and this paper is to lay some foundation with the new approaches such as information flow and modular representation of the physiological models. The ultimate goal is to enhance the development of both the models and the integration approaches of multiscale physiological processes and thus this paper focuses on the design approaches that would achieve such a goal.  相似文献   
96.
采用溶胶-凝胶方法制备了Ti(1-x)CoxO2样品。研究了不同的热处理温度和掺杂浓度对样品晶型和颗粒尺寸的影响。样品400℃热处理呈锐钛矿相,600℃转变为全红石相并且晶粒尺寸明显增大。掺杂对晶型没有影响,但是随掺杂量的增大晶格常数减小。  相似文献   
97.
高性能混凝土配合比设计的试验研究   总被引:2,自引:0,他引:2  
从对HPC组成、结构的认识出发,借鉴利用拨开系数求砂率的方法,提出了一种新的HPC配制方法,并通过试验证实该方法是完全可行的.  相似文献   
98.
文中就无刷柴油发电机的两个输入量,设计了基于单个神经元的双PSD控制器,其智能控制方法简单,响应速度快,MATLAB仿真结果表明,这种控制器对于非线性被控系统具有良好的适应性和鲁棒性.  相似文献   
99.
虚拟现实技术及其在现代医学中的应用   总被引:12,自引:0,他引:12  
虚拟现实是近年来发展起来的一项新的技术,它已经被广泛地应用于许多领域,特别是在医学领域.本文在简述虚拟现实技术的基础上,从虚拟人、辅助诊断和手术、虚拟手术模拟以及虚拟的远程医疗系统四个方面介绍了虚拟现实在医学上的应用.  相似文献   
100.
670 t/h锅炉燃烧系统改造   总被引:1,自引:0,他引:1  
针对扬州发电有限公司200Mw机组4号炉(670t/h)长期存在锅炉灰渣可燃特含量偏高、锅炉效率偏低问题,在详细试验的基础上.对4号炉三次风燃烧系统进行了改造。改造后试验结果表明,4号炉在制粉系统运行条件下,锅炉效率提高2%以上。  相似文献   
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