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开展“三性”模式教学 培养复合型人才 被引量:12
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作者 袁晓明 王宏宇 +1 位作者 刘苏 刘会霞 《实验科学与技术》 2011年第1期67-69,179,共4页
针对目前机械专业实验教学的现状,按照"模块化-递进式"的思想,对"三性"即综合性、设计性和创新性实验教学模式进行了探索,给出了实验教学模式具体的实施措施。通过该实验教学模式的实践,实验教学效果取得了长足的进... 针对目前机械专业实验教学的现状,按照"模块化-递进式"的思想,对"三性"即综合性、设计性和创新性实验教学模式进行了探索,给出了实验教学模式具体的实施措施。通过该实验教学模式的实践,实验教学效果取得了长足的进步,学生的工程意识、综合能力和创新能力有了明显提高。 展开更多
关键词 实验教学 “三性”模式 模块化 递进式
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CUMULATIVE EFFECTS OF DIFFERENT CULTIVATING PATTERNS ON PROPERTIES OF ALBIC SOIL IN SANJIANG PLAIN 被引量:2
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作者 YUAN Zhao-hua LU Xian-guo ZHOU Jia 《Chinese Geographical Science》 SCIE CSCD 2006年第2期133-140,共8页
This paper studied the cumulative effects of different cultivating patterns on the properties of albic soils in the Sanjiang Plain using correlation analysis. The results showed that the physical and chemical properti... This paper studied the cumulative effects of different cultivating patterns on the properties of albic soils in the Sanjiang Plain using correlation analysis. The results showed that the physical and chemical properties of the albic soil changed greatly when it was cultivated as farmland. As for physical properties of the soil, bulk density and specific gravity increased gradually, the porosity and field capacity decreased gradually year by year, but they increased after being abandoned. As for chemical properties, pH increased, organic matter and other nutrients decreased with increasing of the cultivating years. For the albic soil cultivated with forage, the cumulative effects were apparently strengthened with the increase of cultivating years, especially for the bulk density, total porosity, capillary porosity and capillary moisture capacity. Moreover, fertilization also had great effects on the albic soil. Applying magnetism ferti- lizer improved the physical properties such as bulk density, soil moisture and porosity, raised the utilization rate of nitrogen and phosphorus fertilizer. Compared with nutrient fertilizer, utilization of the magnetism fertilizer made production increase by 5.9%-13.9%. At the same time, using organic material and loosing the albic layer could improve not only the physical, chemical and biological properties of the cultivating layer, but also the ill properties of the albic layer, thus making organic carbon and heavy fraction carbon contents increase, and biological activity increase obviously. 展开更多
关键词 cultivating pattern albic soil soil property Sanjiang Plain
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8-Weighted-Type Fractional Fourier Transform Based Three-Branch Transmission Method 被引量:3
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作者 Jing Li Xuejun Sha +1 位作者 Xiaojie Fang Lin Mei 《China Communications》 SCIE CSCD 2018年第9期147-159,共13页
To improve the bit error rate(BER) performance of multiple input multiple output(MIMO) systems with low complexity, a three-branch transmission scheme employing 8-weighted-type fractional Fourier transform(8-WFRFT) mo... To improve the bit error rate(BER) performance of multiple input multiple output(MIMO) systems with low complexity, a three-branch transmission scheme employing 8-weighted-type fractional Fourier transform(8-WFRFT) module is proposed. In the proposed scheme, the original signal is first decomposed into eight sub-signals and then merged into three component signals by the same carrier pattern. The three signals have mathematical constraint relations among themselves that can counteract the channel fading. They are simultaneously transmitted via three independent antennas after delay regulating. At the receiver, an inverse 8-WFRFT module is employed to obtain the estimated original signal by processing the received signal. Then, the bit error rate(BER) performance, transmitting power, transmission rate, power spectrum and computational complexity of the proposed scheme are analysed in detail. Numerical results show that the proposed scheme has a superior performance compared to STBC based three-antenna transmission scheme, in terms of BER performance. 展开更多
关键词 8-weighted-type fractional Fourier transform (8-WFRFT) bit error rate (BER) low complexity multiple input multiple output (MIMO)
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Numerical Investigation on Effect of Vapor Split Ratio to Performance and Operability for Dividing Wall Column 被引量:4
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作者 Laleh Torab Maralani 袁希钢 +2 位作者 罗祎青 龚超 余国琮 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第1期72-78,共7页
Operability problem of dividing wall column (DWC) raised by vapor split was investigated by numerically analyzing four cases defined by different compositions of a three-component mixture. DWCs were firstly designed f... Operability problem of dividing wall column (DWC) raised by vapor split was investigated by numerically analyzing four cases defined by different compositions of a three-component mixture. DWCs were firstly designed for each case by optimizing the vapor split to the two sides of the dividing wall, and then their feasibilities and total annual costs in operation were evaluated against different vapor split ratios. The analysis on the operability of the DWC for four cases was made based on two scenarios: (1) vapor split is shifted by the vapor resistance difference between the column sections in the two sides of the dividing wall and (2) the feed composition is changed. It was demonstrated that the positioning of the dividing wall and the decision on the vapor split may affect significantly the operability of a DWC. 展开更多
关键词 dividing wall column vapor split ratio OPERABILITY
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Three-Dimensional Modes of Fiber Suspensions in the Taylor-Couette Flow
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作者 万占鸿 林建忠 游振江 《Journal of Donghua University(English Edition)》 EI CAS 2007年第1期57-63,共7页
The linear stability analysis of the fiber suspension Taylor-Couette flow against axisymmetric and non-axisymmetric disturbances is investigated. A generalized complex eigenvalue problem generated from the linearized ... The linear stability analysis of the fiber suspension Taylor-Couette flow against axisymmetric and non-axisymmetric disturbances is investigated. A generalized complex eigenvalue problem generated from the linearized set of the three-dimensional governing system equations around the basic Couette azimuthal solution are solved numerically with the Chebyshev spectral method. In a wide range of radius ratios and the magnitudes of counter rotating, critical bifurcation thresholds from the axisymmetric Couette flow to the flow with different azimuthal wave numbers are obtained. The complex dispersion relations of the linearized stability equation system for vortex patterns with different azimuthal wave number are calculated for real axial wave numbers for axially extended vortex structures. 展开更多
关键词 fiber suspensions Taylor-Couette flow hydrodynamic instability.
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THE SPECTRAL THEORY OF CONTRACTIONSON PONTRYAGIN SPACES Π_k(II) 被引量:1
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作者 YAN SHAOZONG CHEN XIAOMAN ZHANG JIANGUO(Institute Of Mathematics,Fudan Unlversityt Shanghai 200433,China) 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 1994年第3期361-372,共12页
This the continuation of[8].The main purpose ofth0 paper Is to gi、 both general formof any unitary extension and unitary dilation of a contraction of Π_k associated with its trianglemodel.
关键词 Pontryagin space CONTRACTION Unitary dilation Unitary extension Triangle model.
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MINIMIZING A LINEAR FRACTIONAL FUNCTION SUBJECT TO A SYSTEM OF SUP-T EQUATIONS WITH A CONTINUOUS ARCHIMEDEAN TRIANGULAR NORM 被引量:1
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作者 Pingke LI Edward P.Fitts Department of Industrial and Systems Engineering,North Carolina State University,Raleigh,NC 27695-7906,US Shu-Cherng FANG Edward P.Fitts Department of Industrial and Systems Engineering,North Carolina State University,Raleigh,NC 27695-7906,USA Department of Mathematical Sciences,Tsinghua University,Beijing 100084,China College of Management,Dalian University of Technology,Dalian 116024,China. 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2009年第1期49-62,共14页
This paper shows that the problem of minimizing a linear fractional function subject to asystem of sup-T equations with a continuous Archimedean triangular norm T can be reduced to a 0-1linear fractional optimization ... This paper shows that the problem of minimizing a linear fractional function subject to asystem of sup-T equations with a continuous Archimedean triangular norm T can be reduced to a 0-1linear fractional optimization problem in polynomial time.Consequently,parametrization techniques,e.g.,Dinkelbach's algorithm,can be applied by solving a classical set covering problem in each iteration.Similar reduction can also be performed on the sup-T equation constrained optimization problems withan objective function being monotone in each variable separately.This method could be extended aswell to the case in which the triangular norm is non-Archimedean. 展开更多
关键词 Fractional optimization fuzzy relational equations triangular norms.
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