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Near generalized balanced tournament designs with block sizes 4 and 5

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Science China mathematics 2009年第9期52卷 1927-1938页

作者： SHAN xiuLing1, 2.1 department of mathematics, Beijing Jiaotong {2., Beijing 100044, China 2.College of mathematics and Information Science, Hebei normal {2., Shijiazhuang 050016, China department of mathematics Beijing Jiaotong University Beijing 100044 China College of mathematics and Information Science Hebei Normal University Shijiazhuang 050016 China

A near generalized balanced tournament design, or an NGBTD(k,m) in short, is a (km+1,k,k-1)-BIBD defined on a (km+1)-set V . Its blocks can be arranged into an m×(km+1) array in such a way that (1) the blocks in every column of the array form a partial parallel class partitioning V\{x} for some point x, and (2. every element of V is contained in precise k cells of each row. In this paper, we completely solve the existence of NGBTD(4,m) and almost completely solve the existence of NGBTD(5,m) with four exceptions.

关键词： near generalized balanced tournament designs frame generalized doubly resolvable packing constructions existence 05B05

Energy consumption simulations of rural residential buildings considering differences in energy use behavior among family members

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Building Simulation 2024年第8期17卷 1335-1358页

作者： xi Luo Lina Du School of Building Services Science and Engineering Xi'an University of Architecture and Technology(XAUAT)Xi'an 710055China State Key Laboratory of Green Building Xi'an 710055China

The“average occupant”methodology is widely used in energy consumption simulations of residential buildings;however,it fails to consider the differences in energy use behavior among family *** on a field survey on the Central shaanxi Plain,to identify the energy use behavior patterns of typical families,a stochastic energy use behavior model considering differences in energy use behavior among family members was proposed,to improve the accuracy of energy consumption simulations of residential *** results indicated that the surveyed rural families could be classified into the following four types depending on specific energy use behavior patterns:families of one elderly couple,families of one middle-aged couple,families of one elderly couple and one child,and families of one couple and one ***,on typical summer days,the results of daily building energy consumption simulation obtained by the“average occupant”methodology were 2..39%and 2.%lower than the simulation results obtained by the model proposed in this study for families of one elderly couple and families of one middle-aged couple,and 13.05%and 2..05%higher for families of one elderly couple and one child,and families of one couple and one *** typical winter days,for the four types of families,the results of daily building energy consumption simulation obtained by the“average occupant”methodology were 2..69%,10.84%,1.2.%,and 8.39%lower than the simulation results obtained by the model proposed in this study,respectively.

关键词： typical energy use behavior pattern differences in occupant behavior building energy consumption simulation stochastic energy use behavior simulation

Recurrence spectra of He atoms in strong external fields

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Science China(Physics,Mechanics & Astronomy) 2004年第4期47卷 477-484页

作者： LIN Shenglu1, LI Hongyun1, WANG Dehua2. ZHAO Wenli1 & GAO Feng1 1. department of Physics, Shandong normal {2., Jinan 2.0014, China 2. department of mathematics and Physics, Shandong Institute of Architecture and Engineering, Jinan 2.0014, China 1. department of Physics Shandong Normal University 250014 Jinan China 2. department of mathematics and Physics Shandong Institute of Architecture and Engineering 250014 Jinan China

By employing a model potential including the electron exchange energy, we extend the semiclassical closed orbit theory to study the multielectron atoms. Using special region-splitting consistent and iterative method, we figure out the closed orbits in the corresponding classical system and calculate the recurrence spectra of triplet helium atoms in parallel electric and magnetic fields at scaled energy ε=?0.03,n≈40,n=0. The core-scattering effects have been taken into account, which lead to more peaks in the spectra. It has also been confirmed by means of the direct comparison between the spectral portrait in such a plot and those of hydrogen case. In order to compare the theoretic results with experiment, we investigate the closed orbits and recurrence spectra of helium atoms for the similar exchange potential but applied only by single electric field at scaled energy ε=?2.7 case. The spectra are in good agreement with the experimental observation. We conclude that our model is correct and it is necessary to consider the exchange effect for determining the photoabsorption spectra of multielectron atoms in strong external fields.

关键词： exchange potential, recurrence spectra, semiclassical closed orbit theory, core-scattering.

Image space analysis for variational inequalities with cone constraints and applications to traffic equilibria

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Science China mathematics 2012年第4期55卷 851-868页

作者： LI Jun 1,& HUANG NanJing 2.1 College of mathematics and Information,China West normal {2.,Nanchong 637009,China 2.department of mathematics,Sichuan {2.,Chengdu 610064,China 1. College of mathematics and Information China West Normal University Nanchong 637009 China2. Department of Mathematics Sichuan University Chengdu 610064 China

In this paper,the image space analysis (for short,ISA) is employed to investigate variational in- equalities (for short,VI) with cone *** separation for VI with cone constraints is characterized by using the normal cone to a regularization of the image,and saddle points of the generalized Lagrangian func- ***-type necessary and sufficient optimality conditions for VI with cone constraints are presented by using a separation *** functions and weak sharpness for VI with cone constraints are also investi- ***,the obtained results are applied to standard and time-dependent traffic equilibria introduced by Daniele,Maugeri and Oettli.

关键词： variational inequality image space analysis linear separation necessary and sufficient optimalitycondition traffic equilibrium

A trust region algorithm for bilevel programing problems

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Chinese Science Bulletin 1998年第10期43卷 820-824页

作者： LIU Guoshan 1, HAN Jiye 2.and WANG Shouyang 3 1. department of mathematics, Beijing {2. university, Beijing 100875, China 2. Institute of Applied mathematics, Chinese Academy of Sciences, Beijing 100080, China 3. Institute of Systems Science, Chi department of mathematics Beijing Normal University Beijing China Institute of Applied mathematics Chinese Academy of Sciences Beijing China Institute of Systems Science Chinese Academy of Sciences Beijing China

A trust region algorithm is proposed for solving bilevel programming problems where the lower level programming problem is a strongly convex programming problem with linear constraints. This algorithm is based on a tr... 详细信息

关键词： bilevel programming problem trust region algorithm global convergence.

LONGTIME BEHAVIOR FOR THE ACTIVATOR-INHIBITOR MODEL

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Systems Science and Mathematical Sciences 2000年第3期13卷 285-291页

作者： WU Jianhua(department of mathematics,{2., xi’an 710062. China)HUANG Aixiang(department of Mathimatics, xi’an Jiaotong university, xi’an 710049, China) 陕西师范大学数学系陕西西安 710062 西安交通大学数学系陕西西安

The paper first discusses the longtime behavior of the activator-inhibitor model, the existence of the maximal attractor is given. Then using the mathematical induction and the properties of linear semigroup, the regularity result for the maximal attractor is obtained. Next, it is proved that its Hausdorff or fractal dimension is ***, further estimates are verilied by Rothe’s inequality and fractional operators, and the existence of inertial manifold is then proved.

关键词： Maximal attractor estimate of dimension inertial manifold activatorinhibitor model

Origin of the Red Earth sequence on the northeastern Tibetan Plateau and its implications for regional aridity since the middle Miocene

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Science China Earth Sciences 2006年第5期49卷 505-517页

作者： WANG xianyan1,7, LU Huayu1,2. JI Junfeg3, WANG xiaoyong1,7, ZHAO Jingbo4, HUANG Baochun5 & LI Zhen6 1. SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, xi’an 710075, China 2. department of Urban and Resources Sciences, Nanjing university, Nanjing 2.0093, China 3. department of Earth Sciences, Nanjing university, Nanjing 2.0093, China 4. department of Geography, shaanxi normal university, xi’an 710062. China 5. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 10002., China 6 department of Geography, Qinghai normal university, xining 810008, China 7. Graduate School of the Chinese Academy of Sciences, Beijing 100039, China 1. SKLLQG Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China 7. Graduate School of the Chinese Academy of Sciences Beijing 100039 China 2. department of Urban and Resources Sciences Nanjing University Nanjing 210093 China 3. department of Earth Sciences Nanjing University Nanjing 210093 China 4. department of Geography Shaanxi Normal University Xi’an 710062 China 5. Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China 6. department of Geography Qinghai Normal University Xining 810008 China

The Red Earth deposit around xining, northeastern Tibetan Plateau, has beenstudied in terms of soil micro-structure, grain-size distribution, major- and trace-elementchemistry and magne-tostratigraphy. Field investigations indicate that the Red Earth sequenceconsists of 2. visually definable yellow-brown and weakly-developed soils interbedded with reddishstrongly-developed soils, and has a similar structure to the aeolian Red Clay deposit on the ChineseLoess Plateau. Grain-size analysis shows that the Red Earth deposit is very fine-grained with anegligible sand fraction ( > 63 μm). Thin-section observations under light microscopy show that thedeposit has a clayey texture and the coarse fraction ( > 10 μm) mainly consists of quartz,feldspar and micas. Pyroxene and hornblende were also observed. This mineralogical composition ofthe coarse fraction is similar to that of the Quaternary loess. In addition, all of the mineralgrains are semi angular semi-angular and are generally finer than 63 μm. There is a good agreementbetween the major and minor trace element chemistry of loess-soil units and the Red Earth *** REE distributions of the loess-soil and the Red Earth deposit are similar in shape, withenriched LREE and fairly flat HREE profiles and a clear negative Eu anomaly. The geochemicalcharacteristics of the Red Earth deposit are also identical to those of upper continental crust,thus indicating a wind-blown origin. Magnetostratigraphic investigation shows that onset of the RedEarth deposition predates 11.4 Ma BP (13.6 Ma at a nearby site). The distribution of the reportedMiocene aeolian loess at Qin''an of the Loess Plateau is still unknown. Our results indicate thatthis aeolian deposit had extended to the northeastern Tibetan Plateau by at least the middleMiocene. The similarity of the element geochemistry between the Red Earth deposit and the overlyingloess shows that they may have similar sources and dynamic transport system, and may indicate thatthe

关键词： Red Earth deposit, Northeastern Tibetan Plateau, aeolian deposit, aridity of Asia, the middle Miocene.

Superconductivity of small metal grains

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Science China(Physics,Mechanics & Astronomy) 2005年第4期48卷 431-441页

作者： ZHENG Renrong1 CHEN Zhiqian2.& ZHU Shunquan1,3 1. department of Physics, Shanghai normal {2., Shanghai 2.02.4, China 2. department of Physics, Southwest normal {2., Chongqing 400715, China 3. department of Computer and Electric Technology, Shanghai Business School, Shanghai 2.1400, China 1. department of Physics Shanghai Normal University 200234 Shanghai China 2. department of Physics Southwest Normal University 400715 Chongqing China 3. department of Computer and Electric Technology Shanghai Business School 201400 Shanghai China

The formulas of the energy gap and superconducting critical temperature appropriate for systems with both odd and even number of electrons are derived; the bases of the derivations are BCS theory and energy level statistics. Numerical results qualitatively agree with the experimental phenomena. i.e., the superconductivity of small metallic grains will first enhance then decrease to zero when the grain are getting smaller and smaller. The calculations indicate that the above phenomena happen in the metallic grains belonging to Gaussian Orthogonal Ensemble (GOE) and Gaussian Unitary ensemble (GUE) with zero spin; The superconductivity of small metallic grains in Gaussian Symplectic Ensemble (GSE) will monotonically decrease to zero with the decreasing of the grain size. The analyses suggest that the superconductivity enhancements come from pairing and the balance of the strengths between spin-orbital coupling and external magnetic field. In order to take the latter into account, it is necessary to include the level statistics given by Random Matrix Theory (RMT) in describing small metallic grains.

关键词： size effect, superconductivity enhancements, small metallic grains.

Approach to synthesis of novel chiral 3-chloro-2.5H)- furanone and its application in asymmetric reactions

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Chinese Science Bulletin 2000年第8期45卷 711-716页

作者： HUANG Hui & CHEN Qinghua1. department of Chemistry, Tonghua Teacher’s College, Tonghua 134002. China 2. department of Chemistry, Beijing {2. university, Beijing 100875, China department of Chemistry Tonghua Teacher’s College Tonghua China department of Chemistry Beijing Normal University Beijing China

The synthetic method of the novel chiral synthon, 5-/-menthyloxy-3-chloro-2.(5H)-furanone 5a and its application in asymmetric reactions were investigated. 5a is easily obtained in highly optical purity, and acts as a stable acceptor of Michael addition with oxygen nucleophiles in tandem double Michael addition / internal nucieophilic substitution to offer the spiro-cyclopropane derivative containing four stereogenic centers 8, which it is difficult to obtain by routine methods. The synthetic methods for 5a and 8 are reported in detail and the new compounds are identified on the basis of their analytical data and spectroscopic data, such as UV, IR, H NMR,13 C NMR, MS and elementary analysis. The absolute configuration of the interesting spiro-cyclopropanes, spiro [1-chloro-4-(/-menthyloxy)-5-oxo-6-oxa-biscyclo[3.1.0]hexane-2.3i(4’-/-menthyloxy-5’-/-menthyloxy- butyrolactone)] 8 was established by X-ray crystallography. This result can provide important synthetic strategy in synthesis of some complex

关键词： new chiral synthon. 5-l-menthyloxy-3-chloro-2.(5H)-furanone absolute configuration spiro-cyclopropane derivative containing multiple chiral centers.