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91.
92.
介绍了如何利用Maxdos等软件将笔记本电脑打造成一个Ghost服务器,同时介绍了如何利用PXE(Pre-boot Execution Environment)、U盘、光盘启动等进行网络恢复。  相似文献   
93.
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   
94.
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   
95.
The characterization of non-stationary signal requires joint time and frequency information. However, time and frequency are a pair of non-commuting variables that cannot constitute a joint probability density in the time-frequency plane. The time-frequency distributions have difficult interpretation problems arising from negative and complex values or spurious components. In this paper, we get time-frequency information from the marginal distributions in rotated directions in the time-frequency plane. The rigorous probability interpretation of the marginal distributions is without any ambiguities. This time-frequency transformation is similar to the computerized axial tomography (CT or CAT) and is applied to signal analysis and signal detection and reveals a lot of advantages especially in the signal detection of the low signal/noise (S/N).  相似文献   
96.
The participation of non-state actors in implementation processes is often understood as a means to increase compliance efficiency. But the implementation of spatial policies frequently focuses on pre-established goals, processes and instruments and thus renders difficult open discourse and shared decision-making. This paper introduces conflict pattern analysis (CPA) as a tool that supports the analysis of the actual actor constellation in order to define efficient approaches that avoid common problems of participatory processes. CPA is a semi-formalised method that helps to identify key-actors, their relations and interaction amongst each other as well as their core beliefs, interests and resources. It aggregates this information to interaction patterns that can be compared, classified and linked to different participatory methods on a theoretically informed basis. Particularly on the local and regional level, this could be the first step for successful (participatory) implementation strategies.  相似文献   
97.
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   
98.
利用有限元软件ANSYS/DYNA,模拟了悬臂和简支钢管混凝土构件的侧向冲击数值,计算了动塑性极限弯矩。  相似文献   
99.
自由幺半群的一族极大自由幺子半群   总被引:1,自引:0,他引:1  
设X*是由字母表X生成的自由幺半群,{B1,B2}是X的任意2—划分,C=B2∪B1XN,N≥1,文[1][2]中证明了C*是自由幺半群X*的幺子半群。以X*为顶点集构造了一个语言图,利用它证明了:对N≥1,C=B2∪XNB1,幺半群C*也是自由幺半群X*的一族极大自由幺子半群.  相似文献   
100.
The geomagnetic fields, which play important roles in the ionospheric dynamo, can greatly affect the global distribution of ionospheric electric fields, currents and other ionospheric electrodynamics phenomena. In the study of ionospheric electrodynamics phenomena, such as the longitudinal variations of ionospheric electric fields, the non-dipolar component of the geomagnetic fields must be taken into account. In this paper, we deduce a theoretical electric field model for ionospheric dynamo at mid- and low-latitude which adopt a modified magnetic apex coordinates system. In the new electric field model, the geomagnetic fields can be calculated from either the IGRF model or the dipole field model, and the neutral winds and conductivities are calculated based on empirical models. Then the dynamo equation for the electric potential is finally solved in terms of the line-by-line iteration method, and the ionospheric electric fields and currents are derived from the calculated potential. Our model can reproduce the main features of the ionospheric electrodynamics processes, so it will be a useful tool for the investigation of the upper atmosphere and ionosphere.  相似文献   
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