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181.
F. H. van Heesch M. A. Klompenhouwer G. de Haan 《Journal of the Society for Information Display》2008,16(10):1009-1019
Abstract— The spatio‐temporal aperture and sample rate of a video display determines both the static and dynamic resolution of the video signal that is rendered. The dynamic display characteristics like the visibility of large‐area flicker, motion judder, and motion blur can be derived from the frame rate and the temporal extent of the pixel aperture (i.e., the temporal aperture). For example, liquid‐crystal displays (LCDs) have an aperture that is relatively small in the spatial dimension and wide in the temporal domain. Consequently, moving objects displayed on an LCD suffer from motion blur. Especially in TV applications, the temporal dimension has a large impact on the overall picture quality. The temporal aperture, together with the frame rate, is shown to predict the amount of perceived large‐area flicker, motion judder, and motion blur and also the performance of motion‐blur reduction algorithms for LCDs. From this analysis it is further determined how to obtain the optimal temporal aperture of a television display, for which not only properties of the human visual system (HVS), but also the properties of the video signal have to be taken into account. 相似文献
182.
A JEOL JEM-3000F field emission, analytical, high-resolution transmission electron microscope (HRTEM) was used to study InN films grown on sapphire substrates. It was found that, while the InN films maintained the hexagonal (wurtzite) structure, InN nanodomains with a cubic (zincblende) structure were also formed in the films. Nanobeam electron diffraction techniques were applied for identification of the cubic phase. The identification of the cubic InN was confirmed by HRTEM structural imaging. The cubic InN nanodomains are 3-10 nm in diameter, and are orientated in two different orientations with their [110](cubic) and [110](cubic) axes parallel to each other and their (111)(cubic) planes parallel to the (0001)(hex) plane of the hexagonal InN. 相似文献
183.
Full instrumental rationality and perfect institutions are two cornerstoneassumptions underlying neoclassical models. However, in the real world, thesetwo assumptions never hold, especially not in developing countries. In thispaper, we develop a game theoretical model to investigate if relaxations inthe full instrumental rationality and perfect institutions premise can explainthe conflicts that have been occurring between the various principals in theNarok district in Kenya with regard to land tenure and use. 相似文献
184.
非均匀抽样网格简化 总被引:2,自引:0,他引:2
提出了一种考虑视点空间中某些重要视点的非均匀抽样网格简化的新方法,是在借鉴了Garland-Heckbert方法的基础上提出的,是一种考虑外观相似性的简化算法。给出并证明了两个判定边界的定理,为抽样提供了理论依据。在简化过程中,该算法通过采用视点空间中某些重要视点对模型进行抽样,使抽中的顶点对(轮廓附近的顶点对)得到适当保护。该算法除具有Garland-Heckbert方法的长处外,还可以在三角面片数较少的情况下(50多个三角面片),尽可能保持模型的重要外观特征,给出了计算0-1图像的外观相似性误差的公式,通过该公式对简化结果进行比较,证明提出的简化算法对保持模型的外观特征是行之有效的。最后对该算法的时间和空间复杂性进行了分析。 相似文献
185.
针对并行设计中冲突协商策略的选取和优化解的非唯一性问题,给出了冲突的数学描述形式以及冲突原因的数学解释,证明了合作策略的优越性,研究了基于Nash定理的冲突协商解的存在性和唯一性,并给出一种协商模型以及具体应用实例. 相似文献
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189.
This paper studies the problem of detecting multiplechanges at unknown times in the mean level of elision in thetrimeter sequences of the Orestes, a play written by theAncient Greek dramatist Euripides (485–406 B.C.). Change-detection statistics proposed by MacNeill (1978) and Jandhayala and MacNeill(1991) are adopted for this purpose. Analysis of the trimetersequences yields several points of change. A general explanation fortheir occurrence appears to be that Euripides varies his use ofelision according to the emotional content of his text, i.e., heseems to change the form to support the content and, thus, seems touse elision frequency as a dramatic instrument. 相似文献
190.
Judy A. Townley 《International journal of parallel programming》1980,9(2):93-116
Resolution theory offers a simple, complete method for proving theorems but is generally considered impractical. The theorems we are interested in proving arise in the analysis of programs and usually involve quantification. We have developed a system for proving these theorems using resolution, but have embedded in it a simplifier as the central component. The simplifier is an integrated collection of algorithms for normalizing arithmetic, relational, and logical expressions. The knowledge in the simplifier is encoded in procedures, rather than as axioms or rules. We use the simplifier to prove certain theorems, reduce the clutter in theorems, and reduce the cost of unification, Inherent in the normal form algorithms is the notion of strengthening (e.g., inferringa =b froma b ANDb a). We have incorporated the notion into the unification algorithm as well. The design of the system permits its use along a spectrum from pure resolution to resolution with interpretation of the arithmetic and relational operators. Strengthening is a heuristic that permits the movement along this spectrum. We call the approachi-resolution.i-resolution does not preserve completeness; it does define a means for approaching completeness efficiently and systematically. It thus attempts to provide a pragmatic approach to mechanical theorem proving. 相似文献