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871.
VC快速处理图像的一种方法 总被引:2,自引:0,他引:2
介绍在Microsoft的可视化平台Visual Studios下,如何为图像申请内存、如何将图像读入内存以及如何快速显示内存中的图像等。这些均是软件开发工作者在进行图像处理或编写应用软件时经常面对的问题。通过VC较好地解决了这一问题。 相似文献
872.
存储ERP/MRP系统中的BOM,指针码的存储效率比层次码高得多,但在进行BOM分解计算时仍需要把指针码转换为层次码的形式,为此,本文对该算法进行了改进,即可以不经过指针码向层次码的转化,直接得到BOM的分解结果,大大简化了操作. 相似文献
873.
The consensus regarding quantum measurements rests on two statements: (i) von Neumann’s standard quantum measurement theory leaves undetermined the basis in which observables are measured, and (ii) the environmental decoherence of the measuring device (the “meter”) unambiguously determines the measuring (“pointer”) basis. The latter statement means that the environment monitors (measures) selected observables of the meter and (indirectly) of the system. Equivalently, a measured quantum state must end up in one of the “pointer states” that persist in the presence of the environment. We find that, unless we restrict ourselves to projective measurements, decoherence does not necessarily determine the pointer basis of the meter. Namely, generalized measurements commonly allow the observer to choose from a multitude of alternative pointer bases that provide the same information on the observables, regardless of decoherence. By contrast, the measured observable does not depend on the pointer basis, whether in the presence or in the absence of decoherence. These results grant further support to our notion of Quantum Lamarckism, whereby the observer’s choices play an indispensable role in quantum mechanics. 相似文献
874.
A. Pirrotta 《International Journal of Non》2005,40(8):1088-1101
Monte Carlo technique is constituted of three steps. Therefore, improving such technique in practice means, improving the procedure used in one of the three following steps: (i) sample paths of the stochastic input process, (ii) calculation of the outputs corresponding to the generated input samples by using methods of classical dynamics and (iii) estimating statistics of the output process from sample outputs related to the previous step. For linear and non-linear systems driven by parametric impulsive inputs such as normal or non-normal white noises, a general integration method requires a considerable reduction of the integration step when the impulse occurs, treating the impulse as a physical one, by means of a window function of finite duration. This makes Monte Carlo simulation very prohibitive from a computational time point of view. While knowing the exact jump value of the response at impulse occurring that is expressed by a numerical series, the aforementioned problem is overcome because there is no need to reduce the integration step saving computational time, reliability being equal as shown by means of a numerical example. 相似文献
875.
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877.
Mohamed Boumazgour 《Journal of Mathematical Analysis and Applications》2008,342(1):386-393
We use certain norm inequalities for 2×2 operator matrices to establish norm inequalities for sums of two basic elementary operators on a Hilbert space. Further, we give necessary and sufficient conditions under which the norm of the above sum of elementary operators attains its optimal value. Applications of the inequalities obtained are also considered. 相似文献
878.
Ond?ej F.K. Kalenda 《Journal of Mathematical Analysis and Applications》2008,340(1):81-101
We collect examples of Valdivia compact spaces, their continuous images and associated classes of Banach spaces which appear naturally in various branches of mathematics. We focus on topological constructions generating Valdivia compact spaces, linearly ordered compact spaces, compact groups, L1 spaces, Banach lattices and noncommutative L1 spaces. 相似文献
879.
Xianling Fan 《Journal of Mathematical Analysis and Applications》2008,339(2):1395-1412
We study boundary trace embedding theorems for variable exponent Sobolev space W1,p(⋅)(Ω). Let Ω be an open (bounded or unbounded) domain in RN satisfying strong local Lipschitz condition. Under the hypotheses that p∈L∞(Ω), 1?infp(x)?supp(x)<N, |∇p|∈Lγ(⋅)(Ω), where γ∈L∞(Ω) and infγ(x)>N, we prove that there is a continuous boundary trace embedding W1,p(⋅)(Ω)→Lq(⋅)(∂Ω) provided q(⋅), a measurable function on ∂Ω, satisfies condition for x∈∂Ω. 相似文献
880.
I. Hoveijn 《Journal of Mathematical Analysis and Applications》2008,348(1):530-539
The level of a function f on Rn encloses a region. The volume of a region between two such levels depends on both levels. Fixing one of them the volume becomes a function of the remaining level. We show that if the function f is smooth, the volume function is again smooth for regular values of f. For critical values of f the volume function is only finitely differentiable. The initial motivation for this study comes from Radiotherapy, where such volume functions are used in an optimization process. Thus their differentiability properties become important. 相似文献