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On s-semipermutable Subgroups of Finite Groups

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Acta Mathematica Sinica,English Series 2010年第11期26卷 2215-2222页

作者： yang ming li Xuan li HE Yan ming WANG Department of Mathematics Guangdong University of Education Guangzhou 510310 P. R. China Department of Mathematics Guangxi University Nanning 530004 P. R. China Department of Mathematics and lingnan College Sun Yat-Sen University Guangzhou 510275 P. R. China

Suppose that G is a finite group and H is a subgroup of G. We say that H is ssemipermutable in G if HGv = GpH for any Sylow p-subgroup Gp of G with （p, ｜H｜） = 1. We investigate the influence of s-semipermutable su... 详细信息

关键词： s-semipermutable subgroup the generalized Fitting subgroup p-nilpotent group saturated formation

Reduction effect of SLM on the PAPR in MC-CDMA system

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Journal of Systems Engineering and Electronics 2005年第4期16卷 761-766页

作者： Yan Biao yang Juan li ming Coll. of Information Engineering Yangzhou Univ. Yangzhou 225009 P. R. China

The model of the MGCDMA system using selective mapping （SLM） is analyzed and the upper bound of the peak-average power ratio （PAPR） in the system is derived. For the PAPR distribution and the connection between the PAPR and the number of users in the MC-CDMA system using SLM, the simulations are given based on several phase sequences in SLM. The simulation results slow that when randdom sequences, Shapiro-Rudin sequences or Golay complementary sequences are selected as the phase sequences in SLM, SLM has obvious effect on the PAPR reduction in MC-CDMA system and the system PAPR nearly maintains constant as the number of users varies. The maximal PAPR in the MC-CDMA system using SLM（10 ttsers）is about 6.3 which is 3.3 less than that in the common MC-CDMA system （without SLM）.

关键词： multicarrier CDMA selective mapping peak-average power ratio phase sequences.

Microscopic Treatment for the Degree of Freedom Beyond the S-D Model Space

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Chinese Physics Letters 1999年第2期16卷 93-94页

作者： LU Da-hai yang li-ming Department of Physics Peking UniversityBeijing 100871

A microscopic treatment of the collective degrees of freedom of nuclei beyond the S-D model space in interacting boson model is *** a similar line as in the case of defining the seniority particle operator,independent of the S degree of freedom in single j-shell,a modified S,D pairs and generalized OBT(operatorized Bogoliubov transformation)are introduced to separate both the S and D degrees of freedom from the rest in the model space of the nucleus spanned by a set of nucleon creation operators c†jm(j=j1,j2,...).

关键词： operator operators collective

Two new flavanonol glycosides from Gordonia chrysandra

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Chinese Chemical Letters 2008年第1期19卷 61-64页

作者： Kun Wang Jing Zhi yang li Zuo Dong ming Zhang Institute of Materia Medica Chinese Academy of Medical Sciences and Key Laboratory of BioactiveSubstances and Resources Utilization of Chinese Herbal Medicine （Peking Union Medical College） Ministry of Education 1 Xiannongtan Street Beijing 100050 China

Two new flavanonol glycosides named chrysandrosides A and B were isolated from the roots of Gordonia chrysandra Cowan. Their structures were determined by 1D and 2D NMR, FAB-MS techniques and chemical methods. Chrysandrosides A and B showed pronounced hepatoprotective activities against o-galactosamine （o-GalN）-induced toxicity in rat hepatic epithelial stemlike cells （WB-F344）. 2007 Dong ming Zhang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Gordonia chrysandra Cowan Flavanonol Chrysandrosides A and B

Selection for high quality pepper seeds by machine vision and classifiers

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Journal of Integrative Agriculture 2018年第9期17卷 1999-2006页

作者： TU Ke-ling li lin-juan yang li-ming WANG Jian-hua SUN Qun Key Laboratory of Crop Genetic Improvement Department of Plant Genetics and Breeding College of Agriculture and Biotechnology China Agricultural University College of Science China Agricultural University

This research aimed to improve selection of pepper seeds for separating high-quality seeds from low-quality seeds. Past research has shown that seed vigor is significantly related to the seed color and size, thus several physical features were identified as candidate predictors of high seed quality. Image recognition software was used to automate recognition of seed feature quality using 400 kernels of pepper cultivar 101. In addition, binary logistic regression and a neural network were applied to determine models with high predictive value of seed germination. Single-kernel germination tests were conducted to validate the predictive value of the identified features. The best predictors of seed vigor were determined by the highest correlation observed between the physical features and the subsequent fresh weight of seedlings that germinated from the 400 seeds. Correlation analysis showed that fresh weight was significantly positively correlated with eight physical features： three color features （R, a＊, brightness）, width, length, projected area, and single-kernel density, and weight. In contrast, fresh weight significantly negatively correlated with the feature of hue. In analyses of two of the highest correlating single features,＇ germination percentage increased from 59.3 to 71.8% when a＊〉3, and selection rate peaked at 57.8%. Germination percentage increased from 59.3 to 79.4%, and the selection rate reached 76.8%, when single-kernel weight 〉0.0064 g. The most effective model was based on a multilayer perceptron （MLP） neural network, consisting of 15 physical traits as variables, and a stability calculated as 99.4%. Germination percentage in a calibration set of seeds was 79.1% and the selection rate was 90.0%. These results indicated that the model was effective in predicting seed germination based on physical features and could be used as a guide for quality control in seed selection. Automated systems based on machine vision and model classifiers can contribu

关键词： pepper seed image processing machine vision seed vigor binary logistic regression multilayer perceptron neural network

Discrimination of individual seed viability by using the oxygen consumption technique and headspace-gas chromatography-ion mobility spectrometry

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Journal of Integrative Agriculture 2023年第3期22卷 727-737页

作者： TU Ke-ling YIN Yu-lin yang li-ming WANG Jian-hua SUN Qun Department of Seed Science and Biotechnology College of Agronomy and BiotechnologyChina Agricultural University/The Innovation Center(Beijing)of Crop Seeds Whole-Process Technology ResearchMinistry of Agriculture and Rural Affairs/Beijing Key Laboratory of Crop Genetic ImprovementBeijing 100193P.R.China College of Arts and Science of Hubei Normal University Huangshi 435109P.R.China College of Science China Agricultural UniversityBeijing 100083P.R.China

Identifying and selecting high-quality seeds is crucial for improving crop *** purpose of this study was to improve the selection of crop seeds based on separating vital seeds from dead seeds,by predicting the potential germination ability of each seed,and thus improving seed *** methods of oxygen consumption (Q) of seeds and the headspace-gas chromatography-ion mobility spectrometry(HS-GC-IMS) were evaluated for identifying the viability of individual ***,the oxygen consumption technique showed clear differences among the values related to respiratory characteristics for seeds that were either vital or not,and the discrimination ability of final oxygen consumption(Q_(120)) was achieved not only in sweet corn seeds but also in pepper and wheat ***,Qtwas established as a new variable to shorten the measuring process in the Q2 (oxygen sensor) procedure,which was significantly related to the viability of individual *** minimize seed damage during measurement,the timing for viability evaluation was pinpointed at the 12,6 and 9 h for pepper,sweet corn,and wheat seeds based on the new variables concerning oxygen consumption (i.e.,Q_(12),Q_(6)and Q_(9),respectively).The accuracies of viability prediction were 91.9,97.7 and 96.2%,*** seeds were identified and hence discarded,leading to an enhancement in the quality of the seed lot as indicated by an increase in germination percentage,from 86.6,90.9,and 53.8%to all at 100%.We then used the HS-GC-IMS to determine the viability of individual sweet corn seeds,noting that corn seed has a heavier weight so the volatile gas components are more likely to be detected.A total of 48 chromatographic peaks were identified,among which 38 target compounds were characterized,including alcohols,aldehydes,acids and ***,there were no significant differences between the vital and dead seeds,due to the trace amount volatile composition differences among the individual ***

关键词： headspace-gas chromatography-ion mobility spectrometry oxygen consumption seed respiration sweet corn tomato wheat

Sub-cover-avoidance Properties and the Structure of Finite Groups

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Communications in Mathematical Research 2009年第5期25卷 418-428页

作者： li yang-ming PENG KANG-TAI Deparment of Matheraatics Guangdong Institute of Education Guangzhou 510310 Department of Mathematics Nanchang University Nanchang 330047

A subgroup H of a group G is said to have the sub-cover-avoidance property in G ffthereis a chief series 1 = G0 ≤ G1 ≤…≤ Gn - G, such that Gi-1（H ∩ Gi） G for every i = 1,2,... ,l. In this paper, we give some characteristic conditions for a group to be solvable under the assumptions that some subgroups of a group satisfy the sub-cover-avoidance property.

关键词： sub-cover-avoidance property maximal subgroup Sylow subgroup,solvable group

On X-s-Permutable Subgroups of a Finite Group

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Journal of Mathematical Research and Exposition 2010年第5期30卷 876-882页

作者： Min Bang SU yang ming li Department of Mathematics Foshan University Guangdong 528000 P. R. China Department of Mathematics Guangdong University of Education Guangdong 510310 P. R. China

Let X be a nonempty subset of a group G. A subgroup H of G is said to be X- s-permutable in G if there exists an element x E X such that HP^x = P^xH for every Sylow subgroup P of G. In this paper, some new results are... 详细信息

关键词： finite group X-s-permutable subgroup the generalized Fitting subgroup formation.

Effect of activated NH_3 on SO_2 removal by pulse corona discharge plasma in flue gas

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Journal of Environmental Sciences 2000年第4期12卷 448-451页

作者： li Jie, WU Yan, WANG Ning\|hui, yang li\|ming (Institute of Electrostatics, Dalian University of Technology, Dalian 116023, China) 大连理工大学辽宁大连 1 1 6 0 2

NH 3 activated electrode is placed in front of the electrode system of pulse corona discharge plasma. There are nozzles on the electrode. Positive DC high\|voltage is applied on the nozzle\|plate gap. NH\-3 is injected into the reactor through nozzles, at the same time, activated and treated. These nozzles were proposed in order to make the additional gas pass through corona discharge regions near the tip of nozzles and increase the mount of radicals. The aim is to improve the De\|SO\-2 efficiency by pulse discharge plasma in flue gas. The following topics are investigated and discussed in the paper: De\|SO\-2 effect of single NH\-3\|activated electrode, De\|SO\-2 effect of activated NH\-3, the relationship between stoichiometric ratio of NH\-3 to SO\-2 and De\|SO\-2 effect of activated NH\-3, mechanism of activated NH\-3 De\|SO\-2 effect. The experimental result indicates that the De\|SO\-2 efficiency can be increased 5%—10% by activated NH\-3 on the original base of De\|SO\-2 efficiency.

关键词： activated NH_3 De-SO_2 pulse discharge