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Exact Periodic-Wave Solutions for(2+1)-Dimensional Boussinesq Equation and (3.1)-Dimensional KP Equation

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Communications in Theoretical Physics 2004年第8期42卷 239-241页

作者： ZHAO Qiang LIU Shi-Kuo FU Zun-Tao School of Physics, Peking university, beijing 100871, China School of Physics Peking University Beijing 100871 China

The(2+1)-dimensional Boussinesq equation and(3.1)-dimensional KP equation are studied by using theextended Jacobi elliptic-function *** exact periodic-wave solutions for the two equations are obtained.

关键词： Jacobi elliptic-function method (2+l)-dimensional Boussinesq equation (3.l)-dimensional KP equation periodic-wave solutions

Impact of the Cooperation Project on Indoor Air Quality of Farmer Household

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Impact of the Cooperation Project on Indoor Air Quality of F...

Structure of augmentation quotients of finite homocyclic abelian groups

作者： Xiao Junhua Guo Jianbin Dong Renjie China Agriculture university,beijing 100083.Jin Xiaobin Medical Science Department of beijing university,beijing 100083.Chen Xiaofu Academy of Planning and Design of the Ministry of Agriculture,beijing 100026

At the project demonstration site,174.farmer households are selected before and after the implementation of the Cooperation Project for testing of indoor air *** hourly concentration of CO and SO in the indoor air of sample farmer households has dropped by 74. and 98% respectively,and the average PMconcentration is dropped by 4.%,the average NH concentration improved by 57%.Through comparison and quantitative analysis,this article proves that domestic energy use model featuring biogas,solar energy and high efficiency firewood saving stoves can greatly improve indoor air quality and the health of farmers.

关键词： renewable energy integrated development indoor air quality inspection and testing

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Science China Mathematics 2007年第9期50卷 1280-1288页

作者： Guo-ping TANG School of Mathematical Sciences,Graduate university of Chinese Academy of Sciences,beijing 10004.,China School of Mathematical Sciences Graduate University of Chinese Academy of Sciences Beijing China

Let G be a finite abelian group and its Sylow p-subgroup a direct product of copies of a cyclic group of order p r , i.e., a finite homocyclic abelian group. Let Δ n (G) denote the n-th power of the augmentation ideal Δ(G) of the integral group ring ?G. The paper gives an explicit structure of the consecutive quotient group Q n (G) = Δ n (G)/Δ n+1(G) for any natural number n and as a consequence settles a problem of Karpilovsky for this particular class of finite abelian groups.

关键词： integral group ring augmentation ideal consecutive quotient of augmentation ideal 16S3. 20C05

THE EXISTENCE OF OVERLARGE SETS OF IDEMPOTENT QUASIGROUPS

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Acta Mathematica Scientia 2004年第2期24卷 165-170页

作者：常彦勋雷建国 DepartmentofMathematics BeijingJiaotongUniversityBeijing100044China

A idempotent quasigroup (Q, o) of order n is equivalent to an n(n-1)×3.partial orthogonal array in which all of rows consist of 3.distinct elements. Let X be a (n+1)-set. Denote by T(n+1) the set of (n+1)n(n-1) ordered triples of X with the property that the 3.coordinates of each ordered triple are distinct. An overlarge set of idempotent quasigroups of order n is a partition of T(n+1) into n+1 n(n-1)×3.partial orthogonal arrays A_x, x∈X based on X\{x}. This article gives an almost complete solution of overlarge sets of idempotent quasigroups.

关键词： Pairwise balanced design conjugate invariant subgroup overlarge set of idempotent quasigroups

Decremental Learning based on Sample-Weighted Support Vector Regression

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Wave coupling between the Tianshan orogen and the deformations in its south and north foreland basins in Cenozoic

第24.中国控制与决策会议

作者： Li Qing 1,2 , Wang Ling 1,2* , Zhang De Zheng 3.,Zhang Wei Cun 1,2 1. School of Automation & Electrical Engineering, university of Science and Technology beijing, beijing {3. China 2. Key Laboratory of Advanced Control of Iron and Steel Process (Ministry of Education), beijing {3. China3. School of Computer & Communication Engineering, university of Science and Technology beijing, beijing {3. China

In this paper, a new modeling method-decremental learning based on sample-weighted SVR（DSWSVR） is proposed, which introduces the decremental learning strategy into sample selection based on support vector regression （SVR）. DSWSVR differs from SVR in that it builds a new sample set, where some sample in the original sample set are weighted differently to account for its representative to improve the prediction ability of the algorithm. Simulation results show that the proposed algorithm can improve the performance of the SVR modeling.

关键词： Support Vector Regression (SVR) Decremental Learning Weighted Sample Genetic Algorithm

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Science China Earth Sciences 2008年第S2期51卷 61-69页

作者： CHEN ShuPing1,2,TANG LiangJie & YU YiXin1,2 1 State Key Laboratory of Petroleum Resource and Prospecting,China university of Petroleum,beijing 10224.,China 2 Department of Geoscience,China university of Petroleum,beijing 10224.,China State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum Beijing China Department of Geoscience China University of Petroleum Beijing China

Attention has been paid to the deformations in the south and north foreland basins of the Tianshan Mountains and their relations to the tectonic movements of the mountains. Based on the seismic data interpretation and field work,the tectonic features,tectonic styles,controlling factors of deformation,deformation time,and their relationships in the three tectonic units were comparably studied. The Ce-nozoic deformations in the two foreland basins were characterized by zonation from south to north,segmentation from west to east,and layering from deep to shallow. The tectonic styles are compres-sive ones,including both basement-involved and cover-detaching. The two foreland basins underwent several times of deformation in Cenozoic and the deformations were transmitted from the Tianshan orogen to the inner basin. The deformation dynamics of the south and north foreland basins of the Tianshan Mountains can be represented by dynamics of orogenic wedges. In terms of the deformations of the wedges with wave-like features,the concept of a wave orogenic wedge was put forward,and a double wave orogenic wedge model was established.

关键词： Tianshan orogen basin-mountain coupling tectonics wave orogenic wedge

Anti-spermatogenic Effects of Ethanol Extract of Mucuna Urens

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Journal of Reproduction and Contraception 2009年第3期20卷 161-168页

作者： Hannah Edim Etta Udoh Paul Bassey Eneobong Effiom Eneobong Okon Bassey Okon Biological Science Department Cross River University of Technology Environmental Biology and Zoology Department University of Calabar Genetics and Biotechnology Department University of Calabar Animal Science Department Faculty of AgricultureUniversity of Calabar

Objective To investigate the age-long claim by the locales that the food thickener, M. urens seed, has antispermatogenic, hence, antifertility effects in man. Methods Eight-week old male Albino rats were used as the mammalian model for this study. They were assigned to four groups of 6 rats each and treatment with the ethanol extract was for a period of 14.d. The treatment regimes were 70 mg/kg, 14. mg/kg, 210 mg/kg and 0 mg/kg BW in groups A, B, C and D, respectively. Extracts were prepared by Soxhlet extraction using 80% ethanol as the extracting solvent. The stock solution was prepared by dissolving 1 g of the paste extract in 10 ml corn oil （vehicle） to make up 100 mg/ml concentration. At the end of the treatment, sperm from the distal caudal epididymis was collected and analyzed for sperm count, sperm motility and sperm morphology. Results Significant reduction was observed in sperm count and sperm motility （P〈0.05）. The mean sperm count for group A was 6.27±0.02×10^6, for group B was 6.16±0.02×10^6 and group C had 6.0±0.0×10^6 sperm cells The control （group D） had a mean sperm count of 6.50±0.09×10^6 which was higher than that of any treated group. Results of the sperm motility test gave the following mean rates for motile sperm cells after treatment： group A, 57.6±% 2.1; group B, 50.0±4.0; group C, 4..0±4.0. The control had the highest mean motility rate of 72.3.2.1. The observed sperm abnormalities included unusual head with large acrosome, looped tailpiece, mid piece with distal droplet, pin head, pyriform head and long *** The anti-spermatogenic effects of the extract on the sperm in the Albino rat may lead to reduction of fertility.

关键词： Mucuna urens anti-spermatogenic sperm count sperm motility sperm morphology

Design of an MRI quadrature-data acquisition card

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Progress in Natural Science:Materials International 2006年第3期16卷 255-259页

作者： JIANG Zhongde, ZU Donglin and GU Xiaofang (Institute of Heavy Ion Physics, beijing Key Laboratory of Medical Physics & Engineering, School of Physics, Peking university,beijing 100871, China) Institute of Heavy Ion Physics Beijing Key Laboratory of Medical Physics and Engineering School of Physics Peking University Beijing 100871 China

A design of a quadrature-data acquisition card based on peripheral component interconnect (PCI) bus for mini-type magnetic resonance imaging (MRI) system is reported. It uses two high speed analog-to-digital converters (ADCs) to sample the MRI signals and two static random access memories (SRAMs) to store the data which will be read to the computer by PCI bus after sampling. All the logic control signals on the card are generated by the field programmable gate array (FPGA). The software Foundation3.1 is used to design the FPGA and achieve useful result after simulating and implementing. The card has some merits that normal commercial cards do not have. For example, the sampling parameters can be varied according to different pulse sequences.

关键词： MRI data acquisition FPGA PCI bus.

CRYSTALLIZATION AND MAGNETIC PROPERTIES OF AMORPHOUS Nd_6Fe_(81)B_(13.ALLOY

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Acta Metallurgica Sinica(English Letters) 1991年第8期4卷 98-102页

作者： GU Benxi ZHAI Hongru Nanjing university,Nanjing,ChinaSHEN Baogen Institute of Physics,Academia Sinica,beijing,China Nanjing Univ Nanjing China

The magnetic properties and the crystallization and its influence on the magnetic and struc- tural properties for rapidly quenched amorphous Nd_6Fe_(81)B-(13. alloy have been *** low temperature magnetic properties,the Curie temperature and the crystallization behavior are discussed.A small addition(6at.-%)of Nd in amorphous Fe-B alloys increases largely the crystallization temperature T_x but causes a decrease of the Curie temperature Tc·A new phase was observed in the sample annealed at 873.K.

关键词： amorphous alloy magnetic properties crystallization structure