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21.
太极学说在普通高校太极拳教学中的运用 总被引:2,自引:1,他引:1
就将太极学说运用到太极拳教学中,提出了几种阴阳辩证的教学方法.实践证明,这些教学方法可达到事半功倍的效果,应该在普通高校太极拳教学中广泛推广. 相似文献
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23.
Changeable size moving window partial least squares (CSMWPLS) and searching combination moving window partial least squares (SCMWPLS) are proposed to search for an optimized spectral interval and an optimized combination of spectral regions from informative regions obtained by a previously proposed spectral interval selection method, moving window partial least squares (MWPLSR) [Anal. Chem. 74 (2002) 3555]. The utilization of informative regions aims to construct better PLS models than those based on the whole spectral points. The purpose of CSMWPLS and SCMWPLS is to optimize the informative regions and their combination to further improve the prediction ability of the PLS models. The results of their application to an open-path (OP)/FT-IR spectra data set show that the proposed methods, especially SCMWPLS can find out an optimized combination, with which one can improve, often significantly, the performance of the corresponding PLS model, in terms of low prediction error, root mean square error of prediction (RMSEP) with the reasonable latent variable (LVs) number, comparing with the results obtained using whole spectra or direct combination of informative regions for a compound. Regions consisting of the combinations obtained can easily be explained by the existence of IR absorption bands in those spectral regions. 相似文献
24.
Spectral quantities of cyclopropane, cyclobutane, cyclohexane, and of several derivatives, have been calculated by a semiempirical all-valence electron SCF-CI MO method. In cyclopropane, HOMO is practically localized in the carbon-frame, and LVMO is purely so. In cyclobutane, these two MO's are based on C-H bonds, while cyclohexane holds an intermediate position. Despite the overall similarity-experimental and computed-of the spectra of these molecules, assignments are non-parallel. Like cyclopropane, cyclobutane can extend conjugation, but to a diminished degree; cyclohexane behaves in this respect like an acyclic alkane. An interpretation of this gradation, in terms of the nature of high-lying MO's, is proposed. 相似文献
25.
为了降低城市交通拥堵及空气污染程度,本文在现有研究的基础上引入罚款政策,利用系统动力学方法原理构建了机动车污染物减排管控模型。通过仿真和比较分析来探索空气污染收费(Air pollution charging fee,简称APCF)、罚款(penalty)和补贴(subsidy)政策(简称A-P-S策略)的作用效果。研究结果表明:一方面,组合策略具有多重绩效,不但能够降低污染损失(经济-环境效益)、死亡人口的生命价值(社会-经济效益)、交通拥堵程度(社会效益)和机动车污染物总量(环境效益),而且能大大改善环境生态承载力(环境效益)和机动车非法出行增长量(社会安全绩效);另一方面,政策在实施过程中也会遇到一定的局限性,如初期的滞后性,后期的“褪色”效应和“反弹”效应,因此,从长期来看,需要及时调整组合方案。最后,根据仿真结果提出了相应的政策建议,进而为城市交通和环保等相关部门提供决策参考。 相似文献
26.
根据实测数据,以多车道公路桥梁车辆荷载效应组合为背景,基于ISO2394提出的原则,探讨了荷载效应组合系数的统计方法,以合理确定参与组合的各种荷载的设计值. 相似文献
27.
赵森 《河北师范大学学报(自然科学版)》1998,22(4):530-533
首次提出递法推引j-j耦合谱项,计算结果很好,该法能抓住关键通过手算快速求出组合组态((j)^n)的J值。最后,对计算结果进行了验证。 相似文献
28.
Some of the blending interpolation methods (which) stated by a convex combination technique are presented. This includes C1 ,C2 blending triangular interpolanls and C1 -blending quadrilateral inter polanls for surfaces. The mentioned methods can be generalized to the construction of C" blending interpolants. 相似文献
29.
Catalytic Enantioselective Reduction of Prochiral Ketones with Chiral Ferrocenyl Amino Alcohols 总被引:1,自引:0,他引:1
The asymmetric reduction of prochiral ketones was catalyzed by a class of recoverable and highly stable chiral ferrocenyl amino alcohols derived from natural amino acids to yield optically active secondary alcohols in high chemical yields and moderate to good enantiomeric excesses. 相似文献
30.
J. David Pinkston Thomas E. Delaney Donald J. Bowling Thomas L. Chester 《Journal of separation science》1991,14(6):401-406
Components of hamster feces ranging from low molecular weight fatty acids through the expected range of triglycerides have been eluted in a single SFC run with simultaneous pressure and temperature programming. Temperature programming from 140°C to 240°C was required to provide optimum conditions for separation of the fatty acids and to move the elution region of the sterol esters away from that of the triglycerides. Data from chemical ionization and electron impact mass spectrometry of compounds separated by SFC were used to confirm identities suggested by retention measurements and to provide tentative identities of unknown compounds. SFC with flame ionization detection was used to compare Soxhlet extraction, off-line supercritical fluid extraction (SFE), and on-line SFE of the feces. Although samples obtained by Soxhlet extraction and SFE produced very similar chromatograms, SFE required far less time and consumed much smaller quantities of organic solvent. 相似文献