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101.
调节对象参数和运动特性随工况变化的分析   总被引:1,自引:1,他引:0  
水轮机调节对象的许多参数都是随运行工况变化的。以调节对象线性化模型为基础,从1个实例计算人手,计算了不同工况下水轮机传递系数和发电机6个参数的变化情况,进而计算这些参数变化对捌节对象特征根的影响。通过汁算表明,其水力振荡衰减速度与出力有关.而系统的其他运动特性随工况变化较小。  相似文献   
102.
在ERP及其他数据库开发项目中.方便而操作风格一致的录入界面是被用户所广泛要求的。笔者在工程项目中总结了部分用户需要的功能.并在PowerBuilder中以基类的形式实现.在加快工程进度和方便用户方面取得了不错的效果。  相似文献   
103.
Due to their simplicity and intuitiveness, swept surfaces are widely used in many surface modelling applications. In this paper, we present a versatile swept surface technique called the boundary constrained swept surfaces. The most distinct feature is its ability to satisfy boundary constraints, including the shape and tangent conditions at the boundaries of a swept surface. This permits significantly varying surfaces to be both modelled and smoothly assembled, leading to the construction of complex objects. The representation, similar to an ordinary swept surface, is analytical in nature and thus it is light in storage cost and numerically very stable to compute. We also introduce a number of useful shape manipulation tools, such as sculpting forces, to deform a surface both locally and globally. In addition to being a complementary method to the mainstream surface modelling and deformation techniques, we have found it very effective in automatically rebuilding existing complex models. Model reconstruction is arguably one of the most laborious and expensive tasks in modelling complex animated characters. We demonstrate how our technique can be used to automate this process.  相似文献   
104.
Heterogeneous object modeling: A review   总被引:2,自引:0,他引:2  
A review on the recent development in heterogeneous object modeling is provided in this paper. General problems and prevalent solutions to the modeling of heterogeneous objects are investigated. Vigorous heterogeneous object representations are roughly classified into three major categories: evaluated models, unevaluated models and composite models. We reveal their similarities and study their strengths and weaknesses in terms of the representational capacities, intuitiveness, exactness, compactness, efficiency and other criteria. Different design paradigms are briefly reviewed to provide an overview of the state-of-the-art in heterogeneous object design. Finally, open problems and possible future directions are discussed.  相似文献   
105.
AVO技术在寻找薄气层中的应用   总被引:3,自引:0,他引:3  
  相似文献   
106.
CIE TC8‐01 has adopted a new color appearance model: CIECAM021 replaces the CIECAM97s.2 The new model consists of a number of refinements and simplifications of the CIECAM97s color appearance model. This article describes further tests to the robustness of the forward and reverse modes. © 2005 Wiley Periodicals, Inc. Col Res Appl, 30, 99–106, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.20087  相似文献   
107.
The importance of studies of alternative (as compared to traditional) methods of nonlinear stochastic parametric identification is demonstrated. Synthesis of a procedure of identification of the parameter, “discrete observer,” with the use of the criterion, “minimum probability of estimation error,” is proposed for the first time. A model example that demonstrates the efficiency of the proposed approach is considered.  相似文献   
108.
An object design framework for structural engineering   总被引:1,自引:0,他引:1  
Object-oriented principles have introduced several useful concepts for developing complex software systems. As a result, several methodologies have been suggested for the overall design of software systems based on these concepts. Methodologies and frameworks for designing objects that are to be part of the software systems are currently lacking. This paper proposes anobject design framework andmethodology, which utilizes the object-oriented concepts, for planning, organizing and designing structural engineering design objects. Design objects in an integrated structural engineering system are complex and often related to each other in various different ways. The paper also identifies several important relationships among structural engineering design objects. These relationships serve as communication channels through wich design objects send messages to and receive responses from each other. Several examples, drawn from reinforced concrete structures, will be presented to demonstrate the object design methodology and to illustrate how the framework is effective in reducing the complexity of design objects in an integrated structural engineering system.  相似文献   
109.
聂守平  卞松玲  刘峰  李爱民  陶纯堪 《中国激光》1996,23(11):1001-1005
研究了三维目标旋转畸变不变光学相关滤波器组的设计原理,完成了滤波器组参数的计算和编码,以及光学相关识别的计算机模拟。  相似文献   
110.
水下成像的现状和发展动向   总被引:5,自引:0,他引:5  
本文以下水成像在军事,海洋开发工程应用为基础,论述了水下观测和成像中采用微光电视摄像机和激光器件及其系统的技术现状和发展动向。  相似文献   
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