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Exploring multiple equilibria for symmetric 2×2 CES/LES pure exchange economies

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Applied Mathematics(A Journal of Chinese Universities) 2010年第2期25卷 137-154页

作者： shi Xiao-jun ZHANG shun-ming School of Economics and Management Beijing University of Aeronautics and Astronautics Beijing 100191 China China Financial Policy Research Center Renmin University of China Beijing 100872 China

This paper explores the existence of 3 equilibria for symmetric 2-individual 2-good CES/LES pure exchange economies. For certain parameterizations in the economies, we show analytically that there are no more than 3 equilibria. We generalize our analytical results of existence of 3 equilibria for a wide range of parameterizations. Then we provide examples of 3 equilibria and parameter zones of 3 equilibria for CES and CES/LES economies.

关键词： Multiple equilibria Cobb-Douglas utility function CES/LES utility function.

New Model for Image Restoration with Different Boundary Conditions

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Acta Mathematicae Applicatae Sinica 2010年第3期26卷 369-380页

作者： Yu-ying shi Qian-shun Chang Department of Mathematics and Physics North China Electric Power University Beijing 102206 China Institute of Applied Mathematics Academy of Mathematics and Systems Science Beijing 100190 China

In this paper, we propose a new time-dependent model for solving total variation （TV） minimization problems in image restoration. The main idea is applying a priori smoothness on the solution image. Five different B... 详细信息

关键词： image restoration Dirichlet BCs periodic BCs reflecting BCs antireflective BCs mean BCs

Modeling and performance evaluation of the sleep mode in the IEEE 802.16e wireless networks with self-similar traffic

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The Journal of China Universities of Posts and Telecommunications 2009年第4期16卷 34-41页

作者： huo Zhan-qiang JIN shun-fu TIAN Nai-shuo WANG Yan College of Information Science and Engineering Yanshan University Qinhuangdao 066004 China College of Science Yanshan University Qinhuangdao 066004 China School of Computer Science and Engineering Hebei University of Technology Tianjin 300401 China

IEEE 802.16e is currently the latest broadband wireless access standard designed to support mobility. In mobile networks, how to control energy consumption is one of the most important issues for battery-powered mobile stations. The standard proposes an energy saving mechanism named ＇sleep mode＇ for conserving the power of mobile stations. According to the operation principle of the sleep mode for downlink traffic in the type I power saving class, considering the self-similar nature of massive multimedia data in wireless networks, a discrete-time batch arrival Geom^x/G/1 queuing model with a close-down time and multiple vacations is built. The batch size is supposed to be Pareto distributed. By employing an embedded Markov chain method, the average queue length and the average sojourn time of the system model are derived. Correspondingly, the performance measures are obtained of the energy saving rate and the average packet delay time for the sleep mode in the IEEE 802.16e. The numerical results demonstrate the dependency relationships between the system performance measures and the system parameters with different offered loads and different self-similar degrees. Furthermore, a cost model is developed to determine the optimum length of the close-down time for minimizing the total system cost.

关键词： IEEE 802.16e sleep mode close-down self-similar energy saving rate

p75NTR signal transduction suppressed by BFAR and p75NTR interactions

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Science China(Life Sciences) 2012年第4期55卷 367-374页

作者： LI HongMei shi HuiLi huo KeKe State Key Laboratory of Genetic Engineering School of Life Sciences Fudan University Shanghai 200433 China

p75NTR is a low-affinity nerve growth factor receptor, which promotes cell proliferation as a positive modulator of high-affinity receptor TrkA, as well as binds with cell ligands to induce apoptosis and mediate death signals. To analyze the regulatory mechanisms of p75NTR, the present study utilized a new membrane yeast two-hybrid system to screen a human fe- tal brain cDNA library. Results identified BFAR, a novel protein that interacts with p75NTR. Interaction specificity was veri- fied by membrane yeast two-hybrid co-transformation assays, in vitro GST pull-down assays, and in vitro co-irnmunopreci- pitation assays. The fluorescent subcellular localization assay revealed that the two proteins co-localized within the cytoplasm. BFAR overexpression in PC-12 and HEK293T cells inhibited the NFnB and JNK signaling pathway, as determined with the luciferase test. Co-transfected p75NTR and BFAR in HEK293T or PC-12 cells, respectively, increased the percentage of cells in the G2/M phase, decreased the number of S-phase cells, and did not change the number of G0/Gl-phase cells.

关键词： p75NTR BFAR membrane yeast two-hybrid protein-protein interaction apoptosis

Fast cooperative trajectory optimization and test verification for close-range satellite formation using Finite Fourier Series method

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Chinese Journal of Aeronautics 2020年第8期33卷 2224-2229页

作者： Mingying huo Zichen FAN Naiming QI Zhiguo SONG Xin shi School of Astronautics Harbin Institute of TechnologyHarbin 150001China China Academy of Launch Vehicle Technology Beijing 100076China

The process of formation reconfiguration for close-range satellite formation should take into account the risk of collisions between *** this end,this paper presents a method to rapidly generate low-thrust collision-avoidance trajectories in the formation reconfiguration using Finite Fourier Series(FFS).The FFS method can rapidly generate the collision-avoidance threedimensional *** results obtained by the FFS method are used as an initial guess in the Gauss Pseudospectral Method(GPM)solver to verify the applicability of the *** with the GPM method,the FFS method needs very little computing time to obtain the results with very little difference in performance *** verify the effectiveness,the proposed method is tested and validated by a formation control *** satellite simulators in the testbed are used to simulate two-dimensional satellite formation *** simulation and experimental results show that the FFS method can rapidly generate trajectories and effectively reduce the risk of collision between *** fast trajectory generation method has great significance for on-line,constantly satellite formation reconfiguration.

关键词： Collision-avoidance Finite Fourier Series(FFS) Satellite formation reconfiguration Satellite simulators Shape-Based(SB)method

Cycloartane triterpenoid and its glucoside isolated from Cassia occidentalis

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Chinese Journal of Natural Medicines 2017年第12期15卷 950-954页

作者： LI shi-Fei LI shun-Lin Institute of Molecular Science Shanxi University State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of Botany Chinese Academy of Sciences

In the present study, one new cycloartane triterpenoid, named cycloccidentalic acid C(1) and its glucoside, cycloccidentaliside VI(2) were isolated from the whole plant of Cassia occidentalis. Their structures were elucidated by a combinational analyses of 1D and 2D NMR data and HRMS. Compound 2 showed modest anti-HIV-1 activity with EC_(50) value of 1.44 μmol·L^(-1) and TI(Therapeutic Index) value of 15.59.

关键词： Cycloartane triterpenoid Cassia occidentalis Cycloccidentalic acid C Cycloccidentaliside Ⅵ

Three-dimensional hierarchical MoS_2/CoS_2 heterostructure arrays for highly efficient electrocatalytic hydrogen evolution

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Green Energy & Environment 2017年第2期2卷 134-141页

作者： Canbin Ouyang shi Feng Jia huo Shuangyin Wang State Key Laboratory of Chem/Bio-Sensing and Chemometrics Provincial Hunan Key Laboratory for Graphene Materials and Devices College of Chemistry and Chemical Engineering Hunan University

Developing non-expensive, highly active and highly stable electrocatalysts for hydrogen evolution has aroused extensive attention, owing to the necessity of novel clean and sustainable energy carriers. In this paper, we report a synthesis of free-standing three-dimensional hierarchical MoS_2/CoS_2 heterostructure arrays through a convenient process. The investigation of electrocatalytic HER performance suggests that the MoS_2/CoS_2 hybrid catalyst exhibits significant enhancement in HER(onsetpotential and potential at a current density of 100 mA cm^(-2) are 20 mV and125 mV, respectively) and superior durability(no shift of current density is observed after a continuous scanning of 3000 times) compared with individual CoS_2 and MoS_2. The superior HER performance was attributed to the formation of the interface between CoS_2 and MoS_2 through the electrochemical characterization, Raman, XPS analysis, and the control experiment. The lower onsetpotential, higher current density, excellent durability, and the free-standing structure of the three-dimensional hierarchical MoS_2/CoS_2 heterostructure array make it a promising cathode catalyst suitable for widespread application.

关键词： MoS2/CoS2 Heterostructure array Free-standing Hydrogen evolution reaction

5,10,15,20-Tetrakis(p-4-fluorobenzoyloxy)phenyl Porphyrin and Its Transition Metal Complexes

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Chemical Research in Chinese Universities 2006年第4期22卷 419-422页

作者： LIU Wei shi Tong-shun LIU Guo-fa College of Materials Science and Engineering Shandong University of TechnologyZibo 255049 P. R. China College of Chemistry Jilin University Changchun 130023 P. R. China

The properties of porphyrins can be changed through the choice of peripheral substituents and inserted metal ions. To obtain porphyrin complexes with novel structures, 5,10, 15,20-tetrakis（p-4-fluorobenzoyloxy） phenyl perphyrin（TFBOPPH2 ） and its transition metal complexes {TFBOPPM [ M = Mn（ Ⅲ ）, Fe（ Ⅲ ）, Co（ Ⅱ ）, Ni（ Ⅱ ）, Cu（ Ⅱ ） and Zn（ Ⅱ ） ] } were synthesized and characterized by means of UV-Vis, IR photoacoustic speetrumetry, ^1H NMR, elemental analyses, molar conductance, and XPS methods. A structure is proposed, in which one porphyrln molecule is coordinated with a transition metal ion in a tetradentate fashion, while the chlorine ion is the balaneeable anion in Fe（ Ⅲ ） and Mn（ Ⅲ ） complexes.

关键词： Porphyrin Synthesis Transition metal Complex

A New Species of the Genus Hebius Thompson,1913(Serpentes:Natricidae)from Yunnan,China

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Asian Herpetological Research 2023年第3期14卷 212-226页

作者： shun MA Shengchao shi Budian AYI Jianping JIANG Chengdu Institute of Biology Chinese Academy of SciencesChengdu 610041SichuanChina University of Chinese Academy of Sciences Beijing 100049China College of Life Sciences Sichuan UniversityChengdu 610065SichuanChina Mangkang Biodiversity and Ecological Station Tibet Ecological Safety Monitor NetworkChangdu 854500TibetChina

A new keelback snake of the genus Hebius,*** ***.,is reported from Jingdong in Yunnan,China based on a combination of molecular and morphological *** closest to *** and *** phylogenetically,this new species is genetically distinct amongst congeners with the mitochondrial Cyt b uncorrected p-distance ranging from 9.5%(***)to 14.8%(***).In addition,this new species can be distinguished from its congeners by a combination of the following morphological characters:(1)body cylindrical,tail relatively short,TaL/TL 0.235–0.243;(2)dorsal scale rows 19-19-17;(3)ventrals 163–166,cloacal plate divided,subcaudals 71–74 pairs;(4)supralabials 8,the first two contact with the nasals;(5)infralabials 9 or 10,preocular 1,postoculars 3;(6)body dorsum sandy beige with the sides yellowish-brown decorated with two brick-red stripes on the dorsolateral scale rows in life;(7)sutures between the labials brick-red in life and taupe in preservative;(8)ventral light yellow with the outer part of each scale brick-red in life;(9)ventrolateral stripes present.

关键词： Hebius jingdongensis sp.nov. molecular phylogeny morphology taxonomy Yunnan province