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基于RDBMS的智能决策支持系统的研究与设计 总被引:4,自引:0,他引:4
文章研究了基于RDBMS的智能决策支持系统(IDSS)的结构模型,提出了IDSS三种基本知识库(事实库,模型库,规则库)的设计方案和问题求解算法。IDSS是在传统的管理信息系统基础上辅助用户做出决策的智能信息系统,是数据库技术和实用信息系统发展的必然趋势。 相似文献
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一个基于组件技术的商业DSS设计与实现 总被引:1,自引:0,他引:1
介绍一个商流计划决策支持系统的设计思想和实现方法 ,并讨论开发基于知识的决策支持系统的策略。对决策支持系统中的问题处理系统和模型库的组织提出了新观点 ,给出PPS的功能结构和模型的三层表示法。把组件技术引入到系统设计与实现中来 ,用三层Client/Server结构来实现DSS。 相似文献
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本文介绍了一种财务分析信息系统的功能组成和设计思想,论述了系统提供的模型描述语言以及模型计算流程,并阐述了该系统的实际工作中的应用。 相似文献
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In this work we considered the stability of a single-bit high-order sigma-delta modulator under dc input. A new approach for stability analysis is proposed. A nonlinear circle map is suggested to model the dynamics of the modulator. An analogy between the dynamics of the sigma-delta modulator and the sinusoidal digital phase-locked loop (DPLL) is studied and an approximate fixed point solution is presented with stability criteria. Suggestions for designing stabilized high-order systems are presented. 相似文献
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《Ergonomics》2012,55(10):1515-1529
The study investigated the effects of using a lower body prototype exoskeleton (EXO) on static limits of stability and postural sway. Measurements were taken with participants, 10 US Army enlisted men, standing on a force platform. The men were tested with and without the EXO (15 kg) while carrying military loads of 20, 40 and 55 kg. Body lean to the left and right was significantly less and postural sway excursions and maximal range of movement were significantly reduced when the EXO was used. Hurst values indicated that body sway was less random over short-term time intervals and more random over long-term intervals with the EXO than without it. Feedback to the user's balance control mechanisms most likely was changed with the EXO. The reduced sway and relatively small changes in sway with increasing load weights suggest that the EXO structure may have functioned to provide a bracing effect on the body. 相似文献
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基于边顶点重要度的网格简化算法及应用 总被引:3,自引:0,他引:3
基于三角形网格边折叠简化思想,提出一种基于边顶点重要度简化算法,采用一种改进的三角形网格数据结构,在预处理中利用二叉树对顶点重要度进行快速排序并记录三角形合并关系,得到所需分辨率下的近似网格模型。 相似文献
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G. Nandakumar 《Computers in Industry》1985,6(1):15-21
This paper describes the development of a Bills of Material Processor (BOM) and shows how a relational data base system could greatly simplify the design and implementation of the processor on a computer. It describes the steps leading to the structuring of the data files based on data obtained from a manufacturing industry. Examples used in the discussion are real in that they refer to the actual development of a BOM processor using the RAPPORT relational data management system. 相似文献
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This paper presents the application of a hybrid controller to the optimization of the movement of a mobile robot. Through hybrid controller processes, the optimal angle and velocity of a robot moving in a work space was determined. More effective movement resulted from these hybrid controller processes. The experimental scenarios involved a five-versus-five soccer game and a MATLAB simulation, where the proposed system dynamically assigned the robot to the target position. The hybrid controller was able to choose a better position according to the circumstances encountered. The hybrid controller that is proposed includes a support vector machine and a fuzzy logic controller. We used the method of generalized predictive control to predict the target position, and the support vector machine to determine the optimal angle and velocity required for the mobile robot to reach the goal. First, we used the generalized predictive control to predict the target position. Then, the support vector machine is used to classify the angle that must be followed by the mobile robot to reach the goal. Next, a fuzzy logic controller is designed to determine the velocity of the left and right wheels of the mobile robot. Thus generated, the velocity was optimized according to the measures obtained by the support vector machine. Finally, based on the optimal velocity of robot, the output membership function was modified. Consequently, the proposed hybrid controller allowed the robot to reach the goal quickly and effectively. 相似文献
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The stability robustness is considered for linear time invariant (LTI) systems with rationally independent multiple time delays against delay uncertainties. The problem is known to be notoriously complex, primarily because the systems are infinite dimensional due to delays. Multiplicity of the delays in this study complicates the analysis even further. And “rationally independent” feature of the delays makes the problem prohibitively challenging as opposed to the TDS with commensurate time delays (where time delays are rationally related). A unique framework is described for this broadly studied problem and the enabling propositions are proven. We show that this procedure analytically reveals all possible stability regions exclusively in the space of the delays. As an added strength, it does not require the delay-free system under consideration to be stable. Our methodology offers a resolution to this question, which has been studied from variety of directions in the past four decades. None of these respectable investigations can, however, deliver an exact and exhaustive robustness declaration. From this stand point the new method has a unique contribution. 相似文献
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大规模城市三维景观实时浏览解决方案研究及实现 总被引:2,自引:1,他引:2
如何实现大规模城市三维景观实时快速浏览是城市景观可视化中的关键问题之一。主要从空间数据组织、管理、调度方面讨论了这一问题,给出了以多层次细节模型简化技术和动态可见裁剪技术为主要技术的解决方案,最后介绍了一个开发城市三维景观实例系统M3DVIEW。 相似文献
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一个中文新词识别特征的研究 总被引:7,自引:0,他引:7
未登录词识别是汉语自动分词的难题之一。中文新词多为时间敏感词或者领域相关词汇,占据未登录词很大比例。针对新词识别问 题,首先总结了已有新词识别特征,然后引入了一个语言学特征。实验结果表明该特征可以提高新词识别率。 相似文献
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Kalyn Tung Michael Miller John Colombi Daniel Uribe Suzanne Smith 《Journal of the Society for Information Display》2014,22(10):535-544
Previous research has demonstrated a loss of helmet‐mounted display (HMD) legibility for users exposed to whole body vibration. A pair of human factors studies was conducted to evaluate the effect of whole body vibration on eye, head, and helmet movements for seated users of a HMD while conducting simple fixation and smooth pursuit tracking tasks. These experiments confirmed that vertical eye motion can be demonstrated, that is consistent with the human visual systems' response to the vestibular–ocular reflex (VOR). Helmet slippage was also shown to occur, which could exacerbate loss of display legibility. The largest amplitudes in eye movements were observed during exposure to sinusoidal vibration in the 4–6 Hz range, which is consistent with the frequencies that past research has associated with whole‐body resonance and the largest decrease in display legibility. Further, the measured eye movements appeared to be correlated with both the angular acceleration of the user's head and the angular slippage of the user's helmet. This research demonstrates that the loss of legibility while wearing HMDs likely results from a combination of VOR‐triggered eye movements and movement of the display. Future compensation algorithms should consider adjusting the display in response to both VOR‐triggered eye and HMD motion. 相似文献
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集设计和评审为一体的协同产品开发平台的设计与实现 总被引:2,自引:0,他引:2
利用先进的网络技术,CSCW技术,设计了一个集产品设计与专家评审于一体的协同产品开发平台,通过该平台将分散于各地的设计人员,评审专家紧密地联系起来,共同参与项目开发的全过程,此外,并就实现协同开发的关键技术进行了深入的探讨。 相似文献
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Mohammad Anwar Hosen Mohd Azlan HussainFarouq S. Mjalli 《Control Engineering Practice》2011,19(5):454-467
Controlling batch polymerization reactors imposes great operational difficulties due to the complex reaction kinetics, inherent process nonlinearities and the continuous demand for running these reactors at varying operating conditions needed to produce different polymer grades. Model predictive control (MPC) has become the leading technology of advanced nonlinear control adopted for such chemical process industries. The usual practice for operating polymerization reactors is to optimize the reactor temperature profile since the end use properties of the product polymer depend highly on temperature. This is because the end use properties of the product polymer depend highly on temperature. The reactor is then run to track the optimized temperature set-point profile. In this work, a neural network-model predictive control (NN-MPC) algorithm was implemented to control the temperature of a polystyrene (PS) batch reactors and the controller set-point tracking and load rejection performance was investigated. In this approach, a neural network model is trained to predict the future process response over the specified horizon. The predictions are passed to a numerical optimization routine which attempts to minimize a specified cost function to calculate a suitable control signal at each sample instant. The performance results of the NN-MPC were compared with a conventional PID controller. Based on the experimental results, it is concluded that the NN-MPC performance is superior to the conventional PID controller especially during process startup. The NN-MPC resulted in smoother controller moves and less variability. 相似文献
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The generation of leak along the pipeline carrying crude oils and liquid fuels results enormous financial loss to the industry and also affects the public health. Hence, the leak detection and localization problem has always been a major concern for the companies. In spite of the various techniques developed, accuracy and time involved in the prediction is still a matter of concern. In this paper, a novel leak detection scheme based on rough set theory and support vector machine (SVM) is proposed to overcome the problem of false leak detection. In this approach, ‘rough set theory’ is explored to reduce the length of experimental data as well as generate rules. It is embedded to enhance the decision making process. Further, SVM classifier is employed to inspect the cases that could not be detected by applied rules. For the computational training of SVM, this paper uses swarm intelligence technique: artificial bee colony (ABC) algorithm, which imitates intelligent food searching behavior of honey bees. The results of proposed leak detection scheme with ABC are compared with those obtained by using particle swarm optimization (PSO) and one of its variants, so-called enhanced particle swarm optimization (EPSO). The experimental results advocate the use of propounded method for detecting leaks with maximum accuracy. 相似文献
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Ute C. Herzfeld Bruce F. Wallin Carlton J. LeuschenJoel Plummer 《Computers & Geosciences》2011,37(11):1793-1801
The objective of this paper is to derive an algorithm for preserving important subscale morphologic characteristics at grids of lower-resolution, in particular for linear features such as canyons and ridge lines. The development of such an algorithm is necessitated by applications that require reduced spatial resolution, as is common in cartographic generalization, GIS applications, and geophysical modeling. Since any algorithm that results in weighted averages, including optimum interpolation and ordinary kriging, cannot reproduce correct depths, a new algorithm is designed based on principles of mathematical morphology. The algorithm described here is applied to derive a subglacial bed of the Greenland Ice Sheet that includes the trough of Jakobshavn Isbræ as a continuous canyon at correct depth in a low-resolution (5-km) digital elevation model (DEM). Data from recent airborne radar measurements of the elevation of the subglacial bed as part of the CReSIS project are utilized. The morphologic algorithm is designed with geophysical ice-sheet modeling in mind, in the following context. Currently occurring changes in the Earth's climate and the cryosphere cause changes in sea level, and the societal relevance of these natural processes motivates estimation of maximal sea-level rise in the medium-term future. The fast-moving outlet glaciers are more sensitive to climatic change than other parts of the Greenland ice sheet. Jakobshavn Isbrae, the fastest-moving ice stream in Greenland, follows a subglacial geologic trough. Since the existence of the trough causes the acceleration of the slow-moving inland ice in the Jakobshavn region and the formation of the ice stream, correct representation of the trough in a DEM is essential to model changes in the dynamics of the ice sheet and resultant sea-level predictions, even if current ice-sheet models can typically be run only at 5-km resolution. The DEM resultant from this study helps to bridge the conceptual gap between data analysis and geophysical modeling approaches. It is available as SeaRISE Greenland bed data set dev1.2 at http://websrv.cs.umt.edu/isis/index.php/SeaRISE_Assessment. 相似文献
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This study explores the possibility of creating landslide susceptibility mappings by using two types of data: (i) an existing subjective geomorphic mapping; and (ii) landslides already identified in the area analyzed. The analysis is conducted using a type of Artificial Neural Network (ANN) named Learning Vector Quantization. For the subjective geomorphic mapping various definitions of stability were considered/analyzed, some using a 2-class system and some using a 5-class system.The study concludes that mappings using an existing subjective geomorphic classification and based on two stability classes can be successfully replicated with the ANN-based approach. However, mappings based on existing landslides and on the 5-class system do not yield results sufficiently accurate for practical applications. Creation of landslide susceptibility mappings involved utilization of data of numerous types (numerical and class-type variables). This study also investigated various methods of data coding and identified the most appropriate method for this type of analysis. 相似文献