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991.
高校实行岗位聘任制涉及到每位教职工的利益,在社会上人事制度改革不断推进的同时,教职工们已经比较认同了聘任制、合同制、任期制等现代人事管理模式。本文在问卷调查统计基础上,应用假设检验法、归纳、分析了教职工们对竞聘的心理活动、评价及思想顾虑;提出了改进竞聘工作的建议。 相似文献
992.
CHEN Tong 《声学学报:英文版》1995,(2)
I.IntroductionInmanycasesthecontinuityofsoundpropagationwithinatubeisbrokenbyaperturesonthetubewallsuchastoneholesonthemainboreofwoodwindmusicalinstruments,rectangularsound-windowofChineseinstrumentshengetc.Thediscontinuityhaseffectonwavccncoun-tCringit.Keefestudicdasing1etoneholeofwoodwindinstrumentandrepresenteditbyaT-sectionequiva1entcirc.it[11.Inthispaper,theapertureontubewa1lisstudiedfromdifferentpointofview,a1thoughtheGreen'sfunctionmethodisalsousedinthetheoreticalana1ysis.Moresimp1er… 相似文献
993.
三维形貌测试系统中的数字信号处理技术 总被引:2,自引:0,他引:2
本文采用一种基于数字滤波的正文解调算法,用于三维形貌测试系统中相位分布的计算。文中考察了频域理想低通滤波器、三阶巴特沃思滤波器、有限冲击响应滤波器以及空域均值滤波器,通过分析滤波器性能和比较处理结果,得出均值滤波器或有限冲击响应滤波器比较适用于类似于变形光栅的窄带信号。采用数字处理方法,可以由一帧变形光栅图迅速、精确地重建物体的形貌。 相似文献
994.
Scanning patterns of a modified AC magnetic bridge are established through the use of finite-width flaws. From these patterns,
the widths and depths of surface flaws can be determined. The technique was also applied fatigue cracks. 相似文献
995.
996.
Alexander G. Yushchenko Sergey F. Shibalkin 《International Journal of Infrared and Millimeter Waves》2007,28(8):621-626
An original transmission line based on a planar waveguide splitter with central dielectric filling is considered. A rigorous
electrodynamics model is presented for calculating propagation parameters of odd eigenmodes. It was determined that the physics
of the wave processes of the line for odd modes is identical to the physics of closed structures, though the structure geometry
is of semi-open character. Numerical experiments prove that new line is very promising for different millimeter wave applications,
such as band pass filters, test fixture, antennae and three-dimensional integrated circuits (TDIC). 相似文献
997.
Weiyi Liang Junhong Wang Hui Zhang 《International Journal of Infrared and Millimeter Waves》2007,28(1):43-50
The Generalized Transmission Line Equations are employed to analyze the circuit parameters of the microstrip lines. The static
distributed capacitances and inductances of non-uniform microstrip lines are extracted. By comparing the differences between
the port’s S-parameters respectively obtained by the extracted static circuit parameters using circuit method and by the Method
of Moment directly, the applicable frequency range of the extracted static distributed circuit parameters can be found. The
results show that the extracted static circuit parameters can be used in a frequency band from DC up to millimeter wave.
This work was supported in part by the National Natural Science Foundation of China under grant no. 60471053, and in part
by the Program for New Century Excellent Talents in University, MOE, China. 相似文献
998.
In banking, the default behaviour of the counterpart is not only of interest for the pricing of transactions under credit risk but also for the assessment of a portfolio credit risk. We develop a test against the hypothesis that default intensities are chronologically constant within a group of similar counterparts, e.g. a rating class. The Kolmogorov–Smirnov‐type test builds up on the asymptotic normality of counting processes in event history analysis. The right censoring accommodates for Markov processes with more than one no‐absorbing state. A simulation study and two examples of rating systems demonstrate that partial homogeneity can be assumed, however occasionally, certain migrations must be modelled and estimated inhomogeneously. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
999.
本文在分析二值 BiCMOS 电路及“开关信号理论”的基础上, 用开关级设计方法提出了新的三值 BiCMOS 电路. 与 CMOS 三值电路相比,新的电路的驱动能力明显要强得多, 因而在大电容负载条件下有更 好的速度性能. 相似文献
1000.
Nir Ailon Bernard Chazelle Seshadhri Comandur Ding Liu 《Random Structures and Algorithms》2007,31(3):371-383
In standard property testing, the task is to distinguish between objects that have a property 𝒫 and those that are ε‐far from 𝒫, for some ε > 0. In this setting, it is perfectly acceptable for the tester to provide a negative answer for every input object that does not satisfy 𝒫. This implies that property testing in and of itself cannot be expected to yield any information whatsoever about the distance from the object to the property. We address this problem in this paper, restricting our attention to monotonicity testing. A function f : {1,…,n} ↦ R is at distance εf from being monotone if it can (and must) be modified at εfn places to become monotone. For any fixed δ > 0, we compute, with probability at least 2/3, an interval [(1/2 − δ)ε,ε] that encloses εf. The running time of our algorithm is O(εf−1 log log εf− 1 log n), which is optimal within a factor of loglog εf−1 and represents a substantial improvement over previous work. We give a second algorithm with an expected running time of O(εf−1 log nlog log log n). Finally, we extend our results to multivariate functions. © 2007 Wiley Periodicals, Inc. Random Struct. Alg., 2007 相似文献