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Applied Mathematics(A Journal of Chinese Universities) 2008年第3期23卷 331-344页

作者： GAO ying rong Wei-dong School of Mathematical Sciences Inner Mongolia University Hohhot 010021 China

This paper studies a class of multiobjective generalized fractional programming problems, where the numerators of objective functions are the sum of differentiable function and convex function, while the denominators are the difference of differentiable function and convex function. Under the assumption of Calmness Constraint Qualification the Kuhn-Tucker type necessary conditions for efficient solution are given, and the Kuhn-Tucker type sufficient conditions for efficient solution are presented under the assumptions of （F, α, ρ, d）-V-convexity. Subsequently, the optimality conditions for two kinds of duality models are formulated and duality theorems are proved.

关键词： operations research multiobjective generalized fractional programming optimality condition duality theorem generalized convexity

FLUID-STRUCTURE INTERACTION OF HYDRODYNAMIC DAMPER DURING THE RUSH INTO THE WATER CHANNEL

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Journal of Hydrodynamics 2008年第5期20卷 583-590页

作者： XU Qing-xin SHEN rong-ying State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong University Shanghai 200240China

The hydrodynamic damper is a device to decrease the motion of armament carrier by use of the water resistance. When hydrodynamic damper rushes into the water channel with high velocity, it is a complicated flow phenomenon with fluid-structure interaction, free surface and moving interface. Numerical simulation using the Smoothed Particle Hydrodynamics （SPH） method coupled with the Finite Element （FE） method was successfully conducted to predict the dynamic characteristics of hydrodynamic damper. The water resistance, the pressure in the interface and the stress of structure were investigated, and the relationship among the peak of water resistance, initial velocity and actual draught was also discussed. The empirical formula was put forward to predict the water resistance. And it is found that the resistance coefficient is commonly in the range of 0.3 ≤ C ≤ 0.5, when the initial velocity is larger than 50 m/s. It can be seen that the SPH method coupled with the FE method has many obvious advantages over other numerical methods for this complicated flow problem with fluid-structure interaction.

关键词： hydrodynamic damper fluid-structure interaction Smoothed Particle Hydrodynamics (SPH) method Finite Element (FE) method

Syntheses,structures,luminescent and magnetic properties of two coordination polymers based on a flexible multidentate carboxylate ligand

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Chinese Chemical Letters 2015年第5期26卷 499-503页

作者： Dan Tian Xiao-Jing Liu rong-ying Chen ying-Hui Zhang Department of Chemistry and TKL of Metal-and Molecule-Based Material Chemistry Key Laboratory of Advanced Energy Materials Chemistry(MOE)and Collaborative Innovation Center of Chemical Science and Engineering(Tianjin)Nankai University

Two coordination polymers, {[Cu3（tci）2（DMAc）3].6DMAc-2H2O}n （1[） and {[Cu3（tci）2（tpt）2（H2O）2]- 2DMAc-2H2O}n （2）（H3tci = tris（2-carboxyethyl）isocyanurate, tpt = 2,4,6-tris（4-pyridyl）-l,3,5-triazine, DMAc = N,N-dimethylacetamide）, have been constructed under solvothermal conditions. Both polymers were structurally characterized by single crystal X-ray diffraction, elemental analyses, IR spectra, thermogravimetric （TG） analyses and powder X-ray diffraction （RXPD）. 1 shows a （3,4）-connected 2D layer structure comprising Cu2（CO2）4 paddle-wheel units, which are further bridged by C-H.--O interactions to give a 3D supramolecular network. The introduction oftpt produces different framework for 2 that comprises a dinuclear and a mononuclear Cu（II） building units, which are further bridged together by tci3- and tpt ligands to give a 4-connected 2D topological net. Adjacent 2D layers are packed together via C-H...O interactions and π...π stacking interactions to form a 3D supramolecular structure. In addition, the luminescent properties and the solid-state UV-vis spectra of I and 2 were explored. Furthermore, antiferromagnetic exchange interactions were unveiled in the Cu2（COO）4 units of 1. ~ 2015 Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences.

关键词： Coordination polymers X-ray crystallography Copper Magnetic properties Luminescence

An INS/GNSS integrated navigation in GNSS denied environment using recurrent neural network

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Defence Technology（防务技术） 2020年第2期16卷 334-340页

作者： Hai-fa Dai Hong-wei Bian rong-ying Wang Heng Ma Navigation Engineering Lab Naval Engineering UniversityWuhanCO430033China

In view of the failure of GNSS signals,this paper proposes an INS/GNSS integrated navigation method based on the recurrent neural network(RNN).This proposed method utilizes the calculation principle of INS and the memory function of the RNN to estimate the errors of the INS,thereby obtaining a continuous,reliable and high-precision navigation *** performance of the proposed method is firstly demonstrated using an INS/GNSS simulation ***,an experimental test on boat is also conducted to validate the performance of the *** results show a promising application prospect for RNN in the field of positioning for INS/GNSS integrated navigation in the absence of GNSS signal,as it outperforms extreme learning machine(ELM)and EKF by approximately 30%and 60%,respectively.

关键词： Inertial navigation system(INS) Global navigation satellite system(GNSS) Integrated navigation Recurrent neural network(RNN)

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Chinese Medical Sciences Journal 2008年第3期23卷 162-165页

作者： Chun-yan Zhang rong rong Xiao-ying Wang Department of Radiology Peking University First Hospital Functional Imaging Center Advanced Academy of Interdisciplinary Sciences Peking University Beijing 100034

Objective To investigate the signal intensity and apparent diffusion coefficient (ADC) of bone marrow of normal adult man on diffusion weighted imaging (DWI). Methods Fifteen healthy volunteers and thirty-eight patients with benign prostatic hyperplasia or normal prostate were enrolled in this study, with age range 28-82 years old (mean 55.26 ± 18.05 years). All people were examined with large field DWI on a 3.0T magnetic resonance scanner, which ranges from the top of head to the lower limb. The signal-to-noise ratio (SNR) on the DWI and ADC of lumber vertebra at renal hilum level, left ilium and superior segment of left femur were measured. The measured SNR and ADC value of the above sites were compared by one way analysis of variance and their correlations with age were investigated by Pearson's correlation analysis. Results The SNR of lumber vertebra, left ilium and left femur showed no significant difference (F = 0.271, P = 0.763). The SNR of lumber vertebra (r = 0.309, P = 0.024) and left ilium (r = 0.359, P = 0.008) showed positive correlation with age, while the SNR of left femur showed no correlation with age (r = -0.163, P = 0.283). The ADC of lumber vertebra [(0.617 ± 0.177) ×10-3 mm2/s] was significantly higher than that of left ilium [(0.404 ± 0.112) ×10-3 mm2/s, P < 0.001] and left femur [(0.362 ± 0.092) ×10-3 mm2/s, P < 0.001], while the ADC of left ilium and left femur had no significant difference. The ADC of lumber vertebra, left ilium and left femur showed no correlation with age. Conclusion Understanding of age-related changes of normal adult bone marrow on DWI is very important to differentiate the normal bone marrow and abnormal lesions.

关键词： diffusion weighted imaging magnetic resonance imaging bone marrow

Pathogenesis of NASH and Promising Natural Products

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Chinese Journal of Natural Medicines 2021年第1期19卷 12-27页

作者： LENG ying-rong ZHANG Mei-Hui LUO Jian-Guang ZHANG Hao State Key Laboratory of Natural Medicines and Jiangsu Key Laboratory of Bioactive Natural Product Research School of Traditional Chinese PharmacyChina Pharmaceutical UniversityNanjing 210009China

Nonalcoholic steatohepatitis(NASH)is a common clinical condition that can lead to advanced liver *** mechanism of the diaease progression,which is lacking effective therapy,remains ***,there is a need to understand the pathogenic mechanisms responsible for disease development and progression in order to develop innovative *** accomplish this goal,experimental animal models that recapitulate the human disease are ***,an increasing number of studies have focused on natural constituents from medicinal plants which have been emerged as a new hope for *** review summarized the pathogenesis of NASH,animal models commonly used,and the promising targets for *** also reviewed the natural constituents as potential NASH therapeutic agents.

关键词： NASH Natural medicine Animal model Target Pathogenesis

Flexibility in matching

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Fundamental Research 2021年第5期1卷 627-630页

作者： Huan Zheng ying rong Antai College of Economics and Management Shanghai Jiao Tong UniversityShanghai 200030China

We examine a service system that matches jobs and candidates with different ability levels.A candidate’s ability will affect the possibility of obtaining a high return on a job *** on the property that the jobs to be assigned to a candidate are substituted in an assignment problem,we propose a novel random parameter generating process to demonstrate that the expected reward increases with the ability level of a candidate at a diminishing *** observation is consistent with the classic result in process flexibility literature that a little flexibility(i.e.,ability level)can capture the most *** observations can help a company decide the proper level of ability.

关键词： Flexibility Service operations Matching and assignment

Traditional Chinese medicine network pharmacology study on exploring the mechanism of Xuebijing Injection in the treatment of coronavirus disease 2019

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Chinese Journal of Natural Medicines 2020年第12期18卷 941-951页

作者： XING Yan HUA ying-rong SHANG Jing GE Wei-Hong LIAO Jun School of Science China Pharmaceutical UniversityNanjing 211198China School of Pharmacy China Pharmaceutical UniversityNanjing 211198China School of Traditional Chinese Pharmacy China Pharmaceutical UniversityNanjing 211198China Department of Pharmacy Nanjing Drum Tower HospitalNanjing 210008China

As a representative drug for the treatment of severe community-acquired pneumonia and sepsis,Xuebijing(XBJ)injection is also one of the recommended drugs for the prevention and treatment of coronavirus disease 2019(COVID-19),but its treatment mechanism for COVID-19 is still ***,this study aims to explore the potential mechanism of XBJ injection in the treatment of COVID-19 employing network pharmacology and molecular docking *** corresponding target genes of 45 main active ingredients in XBJ injection and COVID-19 were obtained by using multiple database retrieval and literature mining.102 overlapping targets of them were screened as the core targets for *** built the PPI network,TCM-compound-target-disease,and disease-target-pathway networks with the help of Cytoscape 3.6.1 *** that,utilized DAVID to perform gene ontology(GO)function enrichment analysis and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment analysis to predict the action mechanism of overlapping ***,by applying molecular docking technology,all compounds were docked with COVID-193 CL protease(3 CLpro),spike protein(S protein),and angiotensin-converting enzyme II(ACE2).The results indicated that quercetin,luteolin,apigenin and other compounds in XBJ injection could affect TNF,MAPK1,IL6 and other overlapping ***,anhydrosafflor yellow B(AHSYB),salvianolic acid B(SAB),and rutin could combine with COVID-19 crucial proteins,and then played the role of anti-inflammatory,antiviral and immune response to treat *** study revealed the multiple active components,multiple targets,and multiple pathways of XBJ injection in the treatment of COVID-19,which provided a new perspective for the study of the mechanism of traditional Chinese medicine(TCM)in the treatment of COVID-19.

关键词： Network pharmacology Molecular docking Xuebijing injection COVID-19

Synthesis and properties of polyfluorene copolymers bearing thiophene and porphyrin

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Chinese Chemical Letters 2007年第7期18卷 879-882页

作者： Xing Xu Hao Chen Xian rong Cai ying Li Qing Jiang College of Chemistry Sichuan University Chengdu 610064 China

To search for more wider absorption and higher charge carriers mobilities materials of polymer solar cell, a series of soluble alternating polyfluorene copolymers were synthesized by palladium-catalyzed Suzuki coupling reaction. Their structures were determined by 1H NMR, IR and UV-vis. And their UV-vis absorption spectra indicated that they had strong absorption over 600 nm spectral range and nearly cover 400-700 nm visible region. The band gaps of copolymers calculated according to cyclic voltammetry （CV） were between 1.96 and 2.03 eV. Polymer：TiO2 bulk-heterojunction films were made from mixtures of polymer and titanium isopropoxide, a precursor for TiO2, via hydrolysis in air overnight. The photoluminescence at 380-800 nm of the blend film of PT-TPP20 （5 mg/mL）：Ti（OC3H7）4 （80 μL/mL）（20% volume fraction） was significantly quenched in the 50% Ti（OC3H7）4 blend film, indicating that rapid and efficient separation of photoinduced electron-hole pairs.

关键词： Polyfluorene copolymers Synthesis Absorption Bulk-heterojunction

Synthesis and Crystal Structure of 4-(4,6-dimethoxyl -pyrimidin-2-yl)-3-thiourea Carboxylic Acid Methyl Ester

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Chinese Journal of Structural Chemistry 2006年第2期25卷 168-172页

作者： HUANG Jie SONG Ji-rong REN ying-Hui XU Kang-Zhen MA Hai-Xia Department of Chemical Engineering Shanxi Key Laboratory of Physico-inorganic Chemistry Northwest Univers＇ity Xi＇an 710069 China

The title compound 4-（4,6-dimethoxylpyrimidin-2-yl）-3-thiourea carboxylic acid methyl ester was synthesized by the reaction of 2-amino-4,6-dimethoxyl pyrimidine, potassium thiocyanate and methyl chloroformate in ethyl acetate. Single crystals suitable for X-ray measurement were obtained by recrystallization with the solvent of dimethyl formamide at the room temperature. The structure was characterized by elemental analysis and IR and determined by X-ray diffraction analysis＇ Crystallographic data： C9H12N4O4S, Mr = 272.29, monoclinic, space group C2/m with a = 1.6672（3）, b = 0.66383（12）, c = 1.1617（2） nm, β = 109.275（2）°, V = 1.2136（4） nm^3, Dc = 1.490 g/cm^3,μ = 0.281 mm^-1, F（000） = 568, Z = 4, R1 = 0.0341and wR2 = 0.1042.

关键词： 4-(4,6-dimethoxylpyrimidin-2-yl)-3-thiourea carboxylic acid methyl ester synthesis X-ray diffraction