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Global Convergence of a Modified PRP Conjugate Gradient Method

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Journal of Mathematical Research and Exposition 2010年第1期30卷 141-148页

作者： Hai Dong HUANG Yan jun li zeng Xin WEI College of Mathematics and Information Science Guangxi University Guangxi 530004 P. R. China

In this paper, a modified formula for βk^PRP is proposed for the conjugate gradient method of solving unconstrained optimization problems. The value of βk^PRP keeps nonnegative independent of the line search. Under mild conditions, the global convergence of modified PRP method with the strong Wolfe-Powell line search is established. Preliminary numerical results show that the modified method is efficient.

关键词： unconstrained optimization conjugate gradient method global convergence.

Study of waveguide coupling efficiency in hybrid silicon lasers

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Optoelectronics Letters 2008年第4期4卷 239-242页

作者： RAN Qi-jiang HAN Pei-de QUAN Yu-jun GAO li-peng zeng Fan-ping ZHAO Chun-hua State Key Laboratory of Integrated Optoelectronics Institute of Semiconductors Chinese Academy of Science Beijing 100083 China

This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon *** find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP *** coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 *** result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 ***,our invariable coupling power technique is simpler than Intel's.

关键词：混合硅激光器波导耦合效率激光技术

A Hybrid Genetic Algorithm for Vehicle Routing Problem with Complex Constraints

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International Journal of Plant Engineering and Management 2006年第2期11卷 88-96页

作者： CHEN Yan LU jun li zeng-zhi School of Electronics and Information Engineering Xi＇an Jiaotong University Xi＇an 710049 P. R. China

Most research on the Vehicle Routing Problem （VRP） is focused on standard conditions, which is not suitable for specific cases. A Hybrid Genetic Algorithm is proposed to solve a Vehicle Routing Problem （VRP） with complex side constraints. A novel coding method is designed especially for side constraints. A greedy algorithm combined with a random algorithm is introduced to enable the diversity of the initial population, as well as a local optimization algorithm employed to improve the searching efficiency. In order to evaluate the performance, this mechanism has been implemented in an oil distribution center, the experimental and executing results show that the near global optimal solution can be easily and quickly obtained by this method, and the solution is definitely satisfactory in the VRP application.

关键词： genetic algorithm vehicle routing problem greedy algorithm complex constraints

Cinobufotalin prevents bone loss induced by ovariectomy in mice through the BMPs/SMAD and Wnt/β-catenin signaling pathways

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Animal Models and Experimental Medicine 2024年第3期7卷 208-221页

作者： Da-zhuang Lu li-jun zeng Yang li Ran-li Gu Meng-long Hu Ping Zhang Peng Yu Xiao Zhang Zheng-wei Xie Hao liu Yong-sheng Zhou Department of Prosthodontics Peking University School and Hospital of StomatologyBeijingChina National Center of Stomatology BeijingChina National Clinical Research Center for Oral Diseases BeijingChina Beijing Key Laboratory of Digital Stomatology BeijingChina Department of Cariology and Endodontology Peking University School and Hospital of StomatologyBeijingChina Peking University International Cancer Institute Peking University Health Science CenterPeking UniversityBeijingChina Central Laboratory Peking University School and Hospital of StomatologyBeijingChina National Engineering Research Center of Oral Biomaterials and Digital Medical Devices BeijingChina

Background:Osteoporosis is a chronic bone disease characterized by bone loss and decreased bone ***,current anti-resorptive drugs carry a risk of various *** deep learning-based efficacy prediction system(DLEPS)is a forecasting tool that can effectively compete in drug screening and prediction based on gene expression *** study aimed to explore the protective effect and potential mechanisms of cinobufotalin(CB),a traditional Chinese medicine(TCM),on bone ***:DLEPS was employed for screening anti-osteoporotic agents according to gene profile changes in primary ***-CT,histological and morphological analysis were applied for the bone protective detection of CB,and the osteogenic differentiation/function in human bone marrow mesenchymal stem cells(hBMMSCs)were also *** underlying mechanism was verified using qRT-PCR,Western blot(WB),immunofluorescence(IF),***:A safe concentration(0.25mg/kg in vivo,0.05μM in vitro)of CB could effectively preserve bone mass in estrogen deficiency-induced bone loss and promote osteogenic differentiation/function of *** BMPs/SMAD and Wnt/β-catenin signaling pathways participated in CB-induced osteogenic differentiation,further regulating the expression of osteogenesis-associated factors,and ultimately promoting ***:Our study demonstrated that CB could significantly reverse estrogen deficiency-induced bone loss,further promoting osteogenic differentiation/function of hBMMSCs,with BMPs/SMAD and Wnt/β-catenin signaling pathways involved.

关键词： BMPs/SMAD bone loss cinobufotalin hBMMSCs osteogenesis osteoporosis Wnt/β-catenin signaling pathways

Effect of Fe content on microstructures and properties of Ti6Al4V alloy with combinatorial approach

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Transactions of Nonferrous Metals Society of China 2018年第9期28卷 1714-1723页

作者： Di WU li-gang ZHANG li-bin liU Wei-min BAI li-jun zeng School of Materials Science and Engineering Central South UniversityChangsha 410083China ZIK Virtuhcon TU Bergakademie FreibergFuchsmühlenweg 9D-09596 FreibergGermany Key Laboratory of Non-ferrous Metallic Materials Science and Engineering of Ministry of Education Central South UniversityChangsha 410083China

A combinatorial approach was applied to investigating the influence of Fe content on the microstructures and properties of Ti6Al4V alloy.A diffusion couple was manufactured with Ti6Al4V and Ti6Al4V20Fe alloys and annealed at 1000°C for 600 h to obtain a wide range of *** combining electron probe micro-analysis(EPMA),scanning electron microscopy(SEM)and nanoindentation,the relationships between composition and microstructure as well as hardness were *** is found that after aging the Ti6Al4V5Fe sample contains reasonable(about 55%)volume fraction of fineαphase and shows the peak hardness among the Ti6Al4VxFe ***,it is a promising candidate for the development of titanium ***-STEM and XRD reveal that after quenching from the singleβphase field,the metastableα''lamellae form in the Ti6Al4V5Fe alloy,and on subsequent isothermal aging,theα''lamellae become coarse and act as precursors/preferential nucleation sites for the stableαphase.

关键词： diffusion multiple Ti6Al4VxFe alloys composition microstructure hardness HAADF-STEM

First Diels-Alder Addct of [60] Fullerene with a Piperidinoxanthate

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有机化学 2003年第Z1期23卷 124-124页

作者： WEN li-jun zeng He-Ping Department of Chemistry South China Normal University Guangzhou 510631 Department of Chemistry South China Normal University Guangzhou 510631

　　In the search for intramolecular energy and electron transfer phenomena in [ 60 ] fullerene donor-containing molecules, some electron donor fragments have been covalently linked to the fullerene core. [1 ～4] Only in very fewcases has reliable evidence of thermal or photoinduced intramolecular electron transfer processes been reported. [5]With the aim of promoting an intramolecular electron transfer we sought to develop a novel type of 6-chlorophenazine derivative of [60]fullerene in which the 6-chloro-phenazine core is directly attached by two σ-bonds to the ball giving rise to a different and more rigid spatial orientation of the HOMO of the 6-chloro-phenazine addend with respect to the LUMO of [60]fullerene.……

关键词： electron transfer processes electron donor type of

Efficacy of the DumonTM Stent in the Treatment of Airway Gastric Fistula： A Case Series Involving 16 Patients

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Chinese Medical Journal 2017年第17期130卷 2119-2120页

作者： Ming-Yao Ke Rui Huang lian-Cheng lin jun-li zeng Xue-Mei Wu Department of the Respiratory Centre Xiamen Second Hospital Teaching Hospital of Xiamen Medical University Xiamen Fujian 361000 China

Airway gastric fistula （AGF） is a rare but dangerous complication following esophagectomy for esophageal cancer,with an incidence rate of 0.3-1.9%.[1] For AGF,the primary goal is closure of the fistula between the digestive and respiratory tracts to avert ongoing soilage of the *** surgical repair remains the definitive treatment,it is associated with a mortality rate of 32%.[2]With the development of interventional therapy,airway stenting has become an effective palliative treatment for *** （Novatech,France） stents have been successfully used to treat AGF for years.[3] We conducted this retrospective study to explore the value of these devices to treat AGF.

关键词： Airway Gastric Fistula Complications DumonTM Stent Efficacy

The Design of the TZ-2 High Voltage Modulator

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Southwestern Institute of Physics Annual Report

Southwestern Institute of Physics Annual Report 2006年第1期 79-80页

作者： WANG Mingwei KANG Zihua HUANG Zhihui RAO jun li Bo zeng Tieliu

This paper introduces the design of the TZ-2 high voltage modulator for electron cyclotron resonance heating （ECRH） on HL-2A tokamak. The high voltage power supplies （HVPS） for the cyclotron have to operate advantageously and flexibly, with high stabilization and good insulation to high-voltage. Moreover, the HVPS must carry out the function of protection quickly, for insure the security of people and devices in the experiment on HL-2A. In this year, the HVPS with these modulators satisfies the requirement of the experiment of HL-2A.

关键词： High-voltage pulse Tetrode Over-current protection

Uniform measure attractors for non-autonomous stochastic evolution systems

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Acta Mathematica Sinica,English Series 2025年

作者： Dingshi li Ran li Tianhao zeng School of Mathematics Southwest Jiaotong University

This paper is concerned with uniform measure attractors for non-autonomous stochastic evolution systems. We first introduce the concept of uniform measure attractor and then provide a sufficient criterion for existence and uniqueness of such attractors. As an application, we prove the existence and uniqueness of uniform measure attractors for the stochastic Navier-Stokes equations with deterministic almost-periodic forcing and nonlinear diffusion terms.

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