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H. Ackermann T. Azemoon W. Gabriel D. Lüke H.D. Mertiens H.D. Reich G. Specht E. Ganssauge F. Janata D. Schmidt 《Nuclear Physics B》1978,133(3):397-407
We report measurements of kaon electroproduction from a hydrogen target carried out at DESY. The invariant cross section for the reaction ep → eK+ + anything is given as a function of the variables q2, W, x, p2⊥ and φ in the following region: . Finally we compare our data with a quark-parton model. 相似文献
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Daniel Reem Simeon Reich Alexander J. Zaslavski 《Journal of Fixed Point Theory and Applications》2007,1(1):149-157
We establish two fixed point theorems for certain mappings of contractive type. The first result is concerned with the case
where such mappings take a nonempty, closed subset of a complete metric space X into X, and the second with an application of the continuation method to the case where they satisfy the Leray–Schauder boundary
condition in Banach spaces. 相似文献
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Colin J. Cotter David A. Ham Christopher C. Pain Sebastian Reich 《Journal of computational physics》2009,228(2):336-348
We introduce a new mixed finite element for solving the 2- and 3-dimensional wave equations and equations of incompressible flow. The element, which we refer to as , uses discontinuous piecewise linear functions for velocity and continuous piecewise quadratic functions for pressure. The aim of introducing the mixed formulation is to produce a new flexible element choice for triangular and tetrahedral meshes which satisfies the LBB stability condition and hence has no spurious zero-energy modes. The advantage of this particular element choice is that the mass matrix for velocity is block diagonal so it can be trivially inverted; it also allows the order of the pressure to be increased to quadratic whilst maintaining LBB stability which has benefits in geophysical applications with Coriolis forces. We give a normal mode analysis of the semi-discrete wave equation in one dimension which shows that the element pair is stable, and demonstrate that the element is stable with numerical integrations of the wave equation in two dimensions, an analysis of the resultant discrete Laplace operator in two and three dimensions on various meshes which shows that the element pair does not have any spurious modes. We provide convergence tests for the element pair which confirm that the element is stable since the convergence rate of the numerical solution is quadratic. 相似文献
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Dr. Axel Reich 《Mathematische Zeitschrift》1970,116(3):218-234
Ohne ZusammenfassungDiese Arbeit wurde von der Deutschen Forschungsgemeinschaft unterstützt. 相似文献
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The proposed method for the recognition of peaks in a chromatogram is based on the k-nearest neighbour (KNN) algorithm, in which the chromatogram is compared with a predefined peak profile. A critical part of the KNN algorithm is the selection of the distance measure used to calculate the similarity between points in the pattern space. Here, five different distance functions are evaluated. In addition to the euclidian distance, which was used in the initial tests of the algorithm, the correlation coefficient, the cross-correlation, and the angle between two vectors and its cosine are tested. All these distance measures show satisfactory behaviour. Their different characteristics are discussed. 相似文献