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121.
张超英 《贵州科技工程职业学院学报》2007,2(2):53-56
探讨了高职院图书馆的现状,提出了高职院图书馆发展的方向,并论述了高职院图书馆的定位问题,最后对图书馆信息资源的建设进行了思考。为建设一个高效、便利的高职院图书馆提供一种思路。 相似文献
122.
文章介绍了黄土湿陷性试验的两种试验方法,对黄土湿陷机理作了简要分析,并对双线法的误差及其修正进行了讨论。 相似文献
123.
文章介绍了为提高物理课堂的教学效果,要充分调动物理课的“本味”和“趣味”,达到学生爱学、乐学的目的。 相似文献
124.
125.
Rein Vihalemm 《Foundations of Science》2007,12(3):223-234
The philosophical analysis of chemistry has advanced at such a pace during the last dozen years that the existence of philosophy of chemistry as an autonomous discipline cannot be doubted any more. The present paper will attempt to analyse the experience of philosophy of chemistry at the, so to say, meta-level. Philosophers of chemistry have especially stressed that all sciences need not be similar to physics. They have tried to argue for chemistry as its own type of science and for a pluralistic understanding of science in general. However, when stressing the specific character of chemistry, philosophers do not always analyse the question ‘What is science?’ theoretically. It is obvious that a ‘monistic’ understanding of science should not be based simply on physics as the epitome of science, regarding it as a historical accident that physics has obtained this status. The author’s point is that the philosophical and methodological image of science should not be chosen arbitrarily; instead, it should be theoretically elaborated as an idealization (theoretical model) substantiated on the historical practice of science. It is argued that although physics has, in a sense, justifiably obtained the status of a paradigm of science, chemistry, which is not simply a physical science, but a discipline with a dual character, is also relevant for elaborating a theoretical model of science. The theoretical model of science is a good tool for examining various issues in philosophy of chemistry as well as in philosophy of science or science studies generally. 相似文献
126.
Global Optimization in Any Minkowski Metric: A Permutation-Translation Simulated Annealing Algorithm for Multidimensional Scaling 总被引:3,自引:1,他引:2
It is well known that considering a non-Euclidean Minkowski metric in Multidimensional Scaling, either for the distance model
or for the loss function, increases the computational problem of local minima considerably. In this paper, we propose an algorithm
in which both the loss function and the composition rule can be considered in any Minkowski metric, using a multivariate randomly
alternating Simulated Annealing procedure with permutation and translation phases. The algorithm has been implemented in Fortran
and tested over classical and simulated data matrices with sizes up to 200 objects. A study has been carried out with some
of the common loss functions to determine the most suitable values for the main parameters. The experimental results confirm
the theoretical expectation that Simulated Annealing is a suitable strategy to deal by itself with the optimization problems
in Multidimensional Scaling, in particular for City-Block, Euclidean and Infinity metrics. 相似文献
127.
张锐梅 《哈尔滨师范大学自然科学学报》2008,24(4)
研究可分拟满Steiner树的结构性质与最优可分拟满Steiner树的生成算法. 相似文献
128.
S. K. MISHRA Shouyang WANG K. K. LAI 《系统科学与复杂性》2007,20(3):344-349
In this paper, we introduce a new class of generalized convex function, namely, a-pseudounivex function, by combining the concepts of pseudo-univex and α-invex functions. Further, we establish some relationships between vector variational-like inequality problems and vector optimization problems under the assumptions of α-pseudo-univex functions. Results obtained in this paper present a refinement and improvement of previously known results. 相似文献
129.
非寿险投资型产品是带有投资性质的非寿险保险产品.现阶段,大力发展非寿险投资型产品是满足多样化金融需求,做大做强非寿险业的客观需要.目前,我国非寿险投资型产品起步晚,规模小,发展很不充分.针对发展过程中的经验教训和出现的问题,应从增加资金运用透明度、提高资金运用专业化、创新产品开发机制等方面采取措施,促进非寿险投资型产品迅速发展. 相似文献
130.
Hong Zhang Kui Zhang Ying Mu Ning Yao Robert J. Sclabassi Mingui Sun 《自然科学进展(英文版)》2008,18(12):1507-1512
Image-based gait analysis as a means of biometric identification has attracted much research attention. Most of the existing methods focus on human identification, posture analysis and movement tracking. There have been few investigations on measuring the carried load based on the carrier's gait characteristics by automatic image processing. Nevertheless, this measurement is very useful in a number of applications, such as the study of the carried load on the postural development of children and adolescence. In this paper, we investigate how to automatically estimate the carried weight from a sequence of images. We present a method to extract human gait silhouette based on an observation that humans tend to minimize the energy during motion. We compute several angles of body leaning and determine the relationship of the carried weight, the leaning angles and the centroid location according to a human kinetic study. Our weight determination method has been verified successfully by experiments. 相似文献