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61.
Yasuo Kanai 《Proceedings of the American Mathematical Society》1999,127(10):3073-3080
In this paper, we present some relations between generalized distributivity of quotient algebras and Mahlo operations, and show that the distributivity implies some variants of stationary relections.
62.
It is common to schedule project activities first, then the utilization of equipment and its operating crew is planned based on such schedule. Real world experiences indicate that activity scheduling can be heavily impacted by the resources needed. In particular, if a project requires highly specialized and expensive equipment type, then one needs to take into account the schedule and cost of such resources in developing the project schedule. 相似文献
63.
Ákos Császár 《Acta Mathematica Hungarica》2005,108(4):351-354
Summary In the paper [5], several operations on generalized topologies are considered. They are not monotone in general, but an old result on monotonicity may be sharpened. 相似文献
64.
La Agusu T. Idehara M. Kamada T. Hayashi V. N. Manuilov O. Dumbrajs K. Yatsui W. Jiang 《International Journal of Infrared and Millimeter Waves》2005,26(5):637-655
Designs of cavities for fundamental and high harmonic operation in Large Orbit Gyrotron (LOG) are discussed. The fundamental operation allows one to use beam currents in the range from 200 A to 300 A achieve output power of the order of 9–10 MW at frequency 143.6 GHz. Mode competition calculations show that stable oscillations in the TE1,4 mode using high beam currents are possible even with the pitch factor 1.3 which is significantly lower than the design value 1.55. For the second harmonic operation, the maximum current used for excitation of the TE2,4 mode is 60 A and the optimum magnetic field is 7.6 T. A cavity design for fourth harmonic operation using the TE4,4 mode is also presented. 相似文献
65.
The axioms of iteration 2-theories capture, up to isomorphism, the equational properties of iteration in conjunction with horizontal and vertical composition in all algebraically complete categories. We give a concrete representation of the free iteration 2-theory generated by a 2-signature. 相似文献
66.
A scheduling model for a production system including machining, setup and assembly operations is considered. Production of a number of single-item products is ordered. Each product is made by assembling a set of several different parts. First, the parts are manufactured in a flow-shop consisting of multiple machines. Then, they are assembled into products on a single assembly stage. Setup operation and setup time are needed when a machine starts processing the parts or it changes items. The operations are partitioned into several blocks. Each block consists of the machining operations, the setup operations, and the assembly operation(s) for one or several products. The parts of the same item in a block are processed successively. The objective function is the mean completion time for all products. We consider a problem to partition the operations into blocks and sequence the parts in each block so as to minimize the objective function. Solution procedures using pseudo-dynamic programming and a branch-and-bound method are proposed. Computational experiments are carried out to evaluate the performance of the solution procedures. It has been found that a good near-optimal schedule is obtained efficiently by the proposed solution procedures. 相似文献
67.
1IntroductionAconsiderableresearcheforthasbeenmadeduringthepastfewyearstodevelopopticallogicoperationsbasedonphotorefractivem... 相似文献
68.
Xinhuan Feng Linghao Cheng Jie Li Zhaohui Li Bai-ou Guan 《Optics & Laser Technology》2011,43(7):1355-1357
A simple approach for photonic generation of a tunable microwave signal is proposed and successfully demonstrated. By mixing the output from a single-longitudinal-mode Brillouin fiber ring laser with the reflected laser pump at photodetector, a microwave signal at the Brillouin shift can be obtained. Since the Brillouin shift can be changed by tuning the pump wavelength, tunable microwave can be generated. As a result a microwave signal tunable from 10.39 to 10.67 GHz has been achieved, with linewidth less than 600 KHz. 相似文献
69.
A novel algorithm for branch cut phase unwrapping 总被引:1,自引:0,他引:1
Dongliang ZhengFeipeng Da 《Optics and Lasers in Engineering》2011,49(5):609-617
Branch cut method is a powerful noise-immune algorithm for correct phase unwrapping of noisy phase maps. The shortest branch cut length promises the optimal unwrapping result of the wrapped phase maps. A new algorithm is proposed to search for the shortest branch cut length by simple exchange operation. Although the algorithm is on the basis of stochastic search techniques, it has a high probability of finding the shortest branch cut length or an approximation of it. Compared with the traditional algorithms, the algorithm is fast and competitive. 相似文献
70.
浅析相关系数的显著性检验 总被引:2,自引:0,他引:2
本文用最小二乘法作直线拟合,给出相关系数显著性检验的判断方法,指出了用概率理论判断线性相关的必要性。 相似文献