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A two-layer optimization model for high-speed railway line planning

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第12期12卷 902-912页

作者： Li WANG Li-min JIA yong QIN Jie XU Wen-ting MO State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University Beijing 100044 China

Line planning is the first important strategic element in the railway operation planning process,which will directly affect the successive planning to determine the efficiency of the whole railway system.A two-layer optimization model is proposed within a simulation framework to deal with the high-speed railway (HSR) line planning *** the model,the top layer aims at achieving an optimal stop-schedule set with the service frequencies,and is formulated as a nonlinear program,solved by genetic *** objective of top layer is tominimize the total operation cost and unserved passenger *** a specific stop-schedule,the bottom layer focuses on weighted passenger flow assignment,formulated as a mixed integer program with the objective of maximizing the served passenger volume andminimizing the total travel time for all *** case study on Taiwan HSR shows that the proposed two-layer model is better than the existing *** addition,this model is also illustrated with the Beijing-Shanghai HSR in *** result shows that the two-layer optimization model can reduce computation complexity and that an optimal set of stop-schedules can always be generated with less calculation time.

关键词： Line plan Stop-schedule Passenger assignment High-speed railway (HSR)

Synthesis and AO Resistant Properties of Novel Polyimide Fibers Containing Phenylphosphine Oxide Groups in Main Chain

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Chinese Journal of Polymer Science 2019年第1期37卷 59-67,1-3页

作者： yong Zhao Hong Gao Guo-min Li Fang-Fang Liu Xue-min Dai Zhi-Xin Dong Xue-Peng Qiu Polymer Composites Engineering Laboratory Changchun Institute of Applied Chemistry Chinese Academy of Sciences University of Chinese Academy of Sciences China Academy of Space Technology

A series of co-polyimide(PI)fibers containing phenylphosphine oxide(PPO)group were synthesized by incorporating the bis(4-aminophenoxy)phenyl phosphine oxide(DAPOPPO)monomer into the PI molecular chain followed by dry-jet wet *** effects of DAPOPPO molar content on the atomic oxygen(AO)resistance of the fibers were investigated *** the AO fluence increased from 0to 3.2×1020the mass loss of the fibers showed the dependence on DAPOPPO molar content in co-PI *** PI fiber containing 40%DAPOPPO showed lower mass loss compared to those containing 0%and 20%*** higher AO fluence,the higher DAPOPPO content gave rise to dense carpet-like surface of *** results indicated that the passivated phosphate layer was deposited on the fiber surface when exposed to AO,which effectively prevented fiber from AO *** the DAPOPPO content increasing from 0%to 40%,the retentions of tensile strength and initial modulus for the fibers exhibited obvious growth from 44%to 68%,and 59%to 70%,after AO exposure with the fluence of 3.2×1020The excellent AO resistance benefits the fibers for application in low Earth orbit as flexible construction components.

关键词： Polyimide fibers Bis(4-aminophenoxy)phenyl phosphine oxide(DAPOPPO) Dry-jet wet spinning AO resistance

A mobility compensation method for drones in SG-eloT

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Digital Communications and Networks 2021年第2期7卷 196-200页

作者： Liguo Weng Yanghui Zhang yong Yang min Fang Zelong Yu State Grid Zhejiang Hangzhou Xiaoshan District Power Supply Co. LtdHangzhouZhejiang311202China Zhejiang Design Institute of Water Conservancy&Hydro-Electric Power HangzhouZhejiang310000China Shenyang Aerospace University Shengyan110000China

In order to achieve the specific goal of a smart grid,the concept of electricity Internet of Things(eloT)has been proposed to assist the monitoring and inspection of power transmission line state and optimize the asset *** long power transmission line and the complex field operation environment urge the introduction of drones into the eloT for fast power transmission line inspection,data collection from sensors for further big data analysis,adaptive control of power line voltage,***,drones can also act as a central communication control or relay point to serve the data exchange among sensors,drones and power transmission line maintenance personnel in the scenario where the conventional mobile communication service is not ***,the fast mobility of drones may affect the signal transmission and position estimation performance,which may further deteriorate the networking *** order to solve this problem,a mobility compensation method is proposed,which includes the steps of frequency offset estimation and relative velocity *** the Monte Carlo simulations,the proposed algorithm shows favorable gains compared with the conventional ones.

关键词： SG-eloT Drones Mobility Frequency offset compensation

Compact Continuous-Wave Nd:YVO4 Laser with Self-Raman Conversion and Sum Frequency Generation

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Chinese Physics Letters 2011年第5期28卷 111-113页

作者： ZHU Hai-yong ZHANG Ge DUAN Yan-min HUANG Cheng-Hui WEI yong College of Physics and Electronic Information Wenzhou UniversityWenzhou 325035 Key Laboratory of Optoelectronic Materials Chemistry and Physics Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002

Low threshold and compact cw Nd:YVO_(4)self-Raman lasers at 1176 nm and sum-frequency mixing of fundamental and first-Stokes wavelengths are demonstrated.A 20-mm Nd:YVO_(4)crystal is adopted in a compact plane-concave *** results show that the cw Raman conversion is sensitive to cavity *** an incident pump power of 22.5 W,output power of 1.53 W at 1175.6 nm is achieved,corresponding to the threshold of only 0.8 W and the slop efficiency of 8.1%.Intra-cavity sum-frequency generation is realized in a type-Ⅱphase-matching cut KTP crystal,480 m W at 558.6 nm is obtained at incident pump power of 12 W.

关键词： pump resonator cavity

Eff ects of early standardized enteral nutrition on preventing acute muscle loss in the acute exacerbation of chronic obstructive pulmonary disease patients with mechanical ventilation

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World Journal of Emergency Medicine 2023年第3期14卷 193-197页

作者： Yue Li yong-peng Xie Xiao-min Li Tao Lu School of International Pharmaceutical Business China Pharmaceutical UniversityNanjing 210009China Department of Emergency and Critical Care Medicine Lianyungang Clinical College of Nanjing Medical UniversityLianyungang 222000China

BACKGROUND:To investigate the eff ects of early standardized enteral nutrition(EN)on the crosssectional area of erector spine muscle(ESMcsa),plasma growth diff erentiation factor-15(GDF-15),and 28-day mortality of acute exacerbation of chronic obstructive pulmonary disease(AECOPD)patients with invasive mechanical ventilation(MV).METHODS:A total of 97 AECOPD patients with invasive MV were screened in the ICUs of the First People's Hospital of *** conventional EN group(stage Ⅰ)and early standardized EN group(stage Ⅱ)included 46 and 51 patients,*** loss and GDF-15 levels on days 1 and 7 of ICU admission and 28-day survival rates were ***:On day 7,the ESMcsa of the early standardized EN group was significantly higher than that of the conventional EN group,while the plasma GDF-15 levels were significantly lower than those in the conventional EN group(ESMcsa:28.426±6.130 cm^(2) vs.25.205±6.127 cm^(2);GDF-15:1661.608±558.820 pg/mL vs.2541.000±634.845 pg/mL;all P<0.001).The 28-day survival rates of the patients in the early standardized EN group and conventional EN group were 80.40%and 73.90%,respectively(P=0.406).CONCLUSION:ESMcsa loss in AECOPD patients with MV was correlated with GDF-15 levels,both of which indicated acute muscular atrophy and skeletal muscle *** standardized EN may prevent acute muscle loss and intensive care unit-acquired weakness(ICU-AW)in AECOPD patients.

关键词： Acute exacerbation of chronic obstructive pulmonary disease Enteral nutrition Cross-sectional area Erector spine muscle Growth diff erentiation factor-15 Intensive care unit-acquired weakness(ICU-AW) Prognosis

Coordination bonds reinforcing mechanical strength of silicon anode to improve the electrochemical stability

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Rare Metals 2024年第11期43卷 5690-5700页

作者： Jin-Huan Li Hong-Qiang Xu min Wu Quan Du yong-Bo Kuang Bo Yin Hai-yong He Key Laboratory of Advanced Fuel Cells and Electrolyzers Technology of Zhejiang Province Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China University of Chinese Academy of Sciences Beijing 101400China Chemistry and Chemical Engineering College Gannan Normal UniversityGanzhou 341000China

The severe volumetric expansion and poor conductivity of silicon when used as anode in lithium-ion batteries present challenges in maintaining the stability of electrochemical ***,the binding between silicon nanoparticles and carbon nanotubes(CNTs)is achieved by the utilization of sodium alginate(S A),which is then strengthened by the coordination between Ca^(2+)and the carboxyl group(-COO^(-))of SA,resulting in a stable conductive network with ionic transport *** consolidated binding relationship enables silicon-based anode material to possess high mechanical strength and strong deformation resistance,preventing the separation of silicon from CNTs ***,this silicon-based anode material demonstrates a discharge specific capacity of811 mAh·g^(-1)after 100 cycles at a current density of 1 A·g^(-1),and exhibits high rate performance,with a discharge specific capacity of 1612 mAh·g^(-1)at 2 A·g^(-1).

关键词： Lithium-ion batteries Silicon Mechanical strength Chemical coordination Cycle stability

Calculation of groundwater head distribution with a close barrier during excavation dewatering in confined aquifer

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Geoscience Frontiers 2021年第2期12卷 791-803页

作者： Hai-min Lyu Shui-Long Shen yong-Xia Wu An-Nan Zhou MOE Key Laboratory of Intelligent Manufacturing Technology Department of Civil and Environmental EngineeringCollege of EngineeringShantou UniversityGuangdongChina State Key Laboratory of Internet of Things for Smart City University of MacaoMacaoChina College of Mechanical and Automotive Engineering Shanghai University of Engineering ScienceShanghai201620China Civil and Infrastructure Discipline School of EngineeringRoyal Melbourne Institute of Technology(RMIT)MelbourneVic3001Australia

When pumping is conducted in confined aquifer inside excavation pit(waterproof curtain),the direction of the groundwater seepage outside the excavation changes from horizontal to vertical owing to the existence of the curtain *** is no analytical calculation method for the groundwater head distribution induced by dewatering inside *** paper first analyses the mechanism of the blocking effects from a close barrier in confined ***,a simple equation based on analytical solution is proposed to calculate groundwater heads inside and outside of the excavation pit with waterproof curtain(hereafter refer to close barrier)in a confined *** distribution of groundwater head is derived according to two conditions:(i)pumping with a constant water head,and(ii)pumping with a constant flow *** proposed calculation equation is verified by both numerical simulation and experimental *** comparisons demonstrate that the proposed model can be applied in engineering practice of excavation.

关键词： Confined aquifer Waterproof curtain Dewatering Groundwater head

Suxiao Jiuxin Pills Prevent Ventricular Fibrillation from Inhibiting L-type Calcium Currents CaV1.2 in vivo and in vitro

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Chinese Journal of Integrative Medicine 2023年第2期29卷 108-118页

作者： QI Jian-yong KANG Dong-yuan YU Juan ZHANG min-zhou Acute Myocardial Infarction Key Laboratory of Chinese Medicine in Guangzhou the 2nd Affiliated Hospital of Guangzhou University of Chinese MedicineGuangdong Province Hospital of Chinese MedicineGuangzhou 510006China Intensive Care Research Team of Traditional Chinese Medicine the 2nd Affiliated Hospital of Guangzhou University of Chinese MedicineGuangdong Province Hospital of Chinese MedicineGuangzhou 510006China Animal Center the 2nd Affiliated Hospital of Guangzhou University of Chinese MedicineGuangdong Province Hospital of Chinese MedicineGuangdong Province Academy of Chinese MedicineGuangzhou 510006China

Objective: To investigate whether Suxiao Jiuxin Pills(SJP), a Chinese herbal remedy, is an anti-ventricular fibrillation(VF) agent. Methods: VF was induced by isoproterenolol(ISO) intraperitoneal injection followed by electrical pacing in mice and rabbits. The effects of SJP on the L-type calcium channel current(CaV1.2), voltage-dependent sodium channel current(INa), rapid and slow delayed rectifier potassium channel current(IKr and IKs, respectively) were studied by whole-cell patch-clamp method. Computer simulation was implemented to incorporate the experimental data of SJP effects on the CaV1.2 current into the action potential(AP) and pseudo-electrocardiography(pseudo-ECG) models. Results: SJP prevented VF induction and reduced VF durations significantly in mice and rabbits. Patch-clamp experiments revealed that SJP decreased the peak amplitude of the CaV1.2 current with a half maximal concentration(IC50) value of 16.9 mg/L(SJP-30 mg/L, –32.8±6.1 pA;Verapamil, –16.2±1.8 pA;vs. control, –234.5±16.7 pA, P0.05). Computer simulation showed that SJP-reduced CaV1.2 current shortened the AP duration,transiting VF into sinus rhythm in pseudo-ECG. Conclusion: SJP reduced VF via inhibiting the CaV1.2 current with in vivo, in vitro, and in silico studies, which provide experimental basis for SJP anti-VF clinical application.

关键词： Suxiao Jiuxin Pills ventricular fibrillation patch clamp simulation CaV1.2

A chirality indicator for the walls and the surfaces of silica nanotubes

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Chinese Chemical Letters 2013年第8期24卷 770-772页

作者： Feng-Wen Hou Li-min Wu yong-min Guo Yi Li Bao-Zong Li Key Laboratory of Organic Synthesis of Jiangsu Province College of ChemistryChemical Engineering and Materials ScienceSoochow University

Single-handed helical silica nanotubes were prepared according to the literature procedures,using the self-assemblies of a pair of chiral cationic low-molecular-weight gelators as the templates.A chirality indicator,4,4＇-bis（triethoxysilyl）-1,1＇-biphenyl,was developed to determine the chirality of the silica *** chirality of the surfaces and the bulky walls of the silica nanotubes were understood from the twist of the biphenylene rings.

关键词： Sol-gel transcription Nanoparticles Silica nanotubes Self-assembly Chirality indicator