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951.
Colour is the most widely used attribute in image retrieval and object recognition. A technique known as histogram intersection has been widely studied and is considered to be effective for color‐image indexing. The key issue of this algorithm is the selection of an appropriate color space and optimal quantization of the selected color space. The goal of this article is to measure the model performance in predicting human judgment in similarity measurement for various images, to explore the capability of the model with a wide set of color spaces, and to find the optimal quantization of the selected color spaces. Six color spaces and twelve quantization levels are involved in evaluating the performance of histogram intersection. The categorical judgment and rank order experiments were conducted to measure image similarity. The CIELAB color space was found to perform at least as good as or better than the other color spaces tested, and the ability to predict image similarity increased with the number of bins used in the histograms, for up to 512 bins (8 per channel). With more than 512 bins, further improvement was negligible for the image datasets used in this study. © 2005 Wiley Periodicals, Inc. Col Res Appl, 30, 265–274, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.20122 相似文献
952.
The use of a sequential linear complementarity problem (SLCP) algorithm for finding a global minimum of bilinear programming problem (BLP) or a concave quadratic program (CQP) is examined. The algorithm consists of solving a sequence of linear complementarity problems (LCP). A branch-and-bound method is also considered in this study. This algorithm is based on the reformulation of a BLP into an LCP with a linear function to minimize. Computational experience with small and medium scale BLPs and CQPs indicates that the SLCP algorithm is quite efficient in finding a global minimum (or at least a solution that is quite near the optimum), but it is, in general, unable to establish that such a solution has been found. An algorithm to find a lower-bound for the BLP can overcome this drawback in some cases. Furthermore the SLCP algorithm is shown to be robust and compares favorably with the branch-and-bound method and another alternative technique. 相似文献
953.
Bernard H. Carson 《Computers & Education》1991,16(4)
The determination of planar properties—cross sectional areas, centroids, moments of inertia, and so forth—plays a central role in the solution of many diverse engineering problems. Despite the increasing availability of computational power to engineers and students alike in recent years with the advent of small desktop computers, however, the traditionally laborious and error-prone methods of making these determinations, involving area decomposition or strip integration, are still being taught to the present generation of engineering students, mostly due to a lack of suitable alternative techniques. These classical methods are found to be particularly difficult to adapt to general computational algorithms. This work presents a novel approach, requiring only the peripheral points of any planar area as inputs, and is ideally suited for numerical methods. It is shown that all planar properties of technical interest can be generated, once and for all, with straightforward algorithms that are readily programmed in any scientific computing language, or adapted to typical spreadsheet formats. These algorithms are fully general and require no decision-making on the part of the user. Various worked examples are presented. 相似文献
954.
K. Fujii J. Fujimoto H. Hayashii R. Kajikawa Y. Masatani H. Ozaki A. Sugiyama R. Suzaki S. Suzuki T.Y. Tsukamoto T.F. Tsukamoto S. Uno S. Iwata 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1985,236(1):55-63
We constructed and tested a prototype gas sampling electromagnetic calorimeter of the Pb-proportional tube sandwich type. The calorimeter uses conductive plastic tubes and cathode pad readout with a tower structure which resulted in reasonable energy and spatial resolutions for electrons in the momentum range 0.5–4.0 GeV/c; /c). This paper describes the test and the performance studied under various conditions. 相似文献
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959.
Brown Michael T.; White Michael J.; Gerstein Lawrence H. 《Canadian Metallurgical Quarterly》1989,36(2):183
Examined the association between self-monitoring and occupational preferences. 237 undergraduates completed Snyder and Gangestad's (1986) revised self-monitoring scale and Holland's (1977) Vocational Preference Inventory (VPI). Regression analyses showed that men who valued congruence between their beliefs and behavior (i.e., low self-monitors) preferred social occupations. Men who were inclined to modify their behavior to fit social situations (i.e., high self-monitors) preferred enterprising occupations. In contrast, high self-monitoring women preferred artistic occupations. It is argued that these gender-neutral occupations permit high self-monitoring women to use their social skills but without the constraints found in male dominated enterprising occupations. Results support the assumption that people prefer occupations compatible with their social skills. Implications for career counseling and further research are noted. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
960.
Examined the theory that chronic migraine headaches can lead to permanent changes in brain function in 71 female college students. Ss were 20 classic migraineurs, 27 common migraineurs, and 24 controls. No significant group differences were found on the Halstead Reitan Neuropsychological Test Battery and additional memory tests. Classic migraineurs had significantly higher scores than common migraineurs on the Hysteria and Paranoia scales of the Minnesota Multiphasic Personality Inventory (MMPI) and significantly higher scores than the controls on Hypochondriasis and Hysteria scales. Explanations for the lack of cognitive deficits in this group are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献