检索结果-南通市图书馆

Repair tolerance assessment for aircraft composite structures using Bayesian updating

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2024年第6期37卷 360-391页

作者： xin LI Hongfu zuo Bin YANG School of Automotive and Rail Transit Nanjing Institute of TechnologyNanjing 211167China Civil Aviation Key Laboratory of Aircraft Health Monitoring and Intelligent Maintenance College of Civil AviationNanjing University of Aeronautics and AstronauticsNanjing 211106China

Detection and repair of composite damage is crucial to ensure the safety and reliability of aircraft structures.A novel approach to quantitatively evaluate the repair tolerance of composite structures in civil aircraft based on Bayesian updating is *** method incorporates historical damage inspection data to determine the prior distribution of damage size,which is then updated with newly collected damage size data using Bayesian *** Carlo simulation is employed to investigate the probability of failure and estimate maintenance costs,considering various factors such as the frequency and timing of damage events,damage detection,structural strength,gust loads,and maintenance expenses throughout the lifecycle of composite *** and economic factors are considered to establish a lower threshold for repairs and an upper threshold for maintenance based on the occurrence of accidental impact *** of the effectiveness and feasibility of a quantitative assessment method for repair tolerance is conducted using damage statistics data from civil aircraft routes utilizing the structural skin panels of composite outer *** results demonstrate that the method proposed in conjunction with extensive simulations and full utilization of field damage inspection data can effectively simulate unexpected impact damage situations that may occur during civil aircraft service and evaluate the reliability and economic feasibility of the repair of *** research findings hold significant theoretical and practical value for the preparation of documents for continued airworthiness of composite structures,including structural repair manuals and maintenance programs.

关键词： Composite structures Repair tolerance Maintenance Bayesian updating Probability of failure

A Dietary Supplement Jinghuosu Ameliorates Reproductive Damage Induced by Tripterygium Glycosides

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Integrative Medicine 2024年第4期30卷 330-338页

作者： MA Jing SUN Bo TE Li-ger HUANG xin zuo xin HAN Xiao-ke wang Shu-song Hebei Key Laboratory of Reproductive Medicine Hebei Institute of Reproductive HealthHebei Reproductive Health HospitalShijiazhuang(050071)China Graduate School of Hebei Medical University Shijiazhuang(050017)China School of Chemistry and Materials Science Hebei Normal UniversityShijiazhuang(050024)China xingtai Infertility Specialist Hospital XingtaiHebei Province(054000)China

Objective To determine the possible protective effects of Jinghuosu,a dietary supplement(DS),on tripterygium glycosides(TG)-induced reproductive system injury in rats and its underlying *** A reproductive damage model was established in rats by feeding of ***-eight male Sprague Dawley rats were randomly divided into 4 groups using a random number table(n=7 in each):control(C)group,model(M)group,DS group and L-carnitine(LC)*** in M,DS and LC groups received 40 mg/kg TGs *** from the 5th week,after administration of TGs for 4 h every day,rats in DS and LC groups were administered with 2.7 g/kg DS and 0.21 g/kg LC,respectively,for protective treatment over the next 4 *** in Group C continued to receive the control ***-eosin staining was used for histopathological analysis of rat testicular ***-linked immunosorbent assay was performed to measure alkaline phosphatase(ALP),lactate dehydrogenase,alcohol dehydrogenase,total antioxidant capacity(T-AOC),superoxide dismutase,glutathione peroxidase(GSH-Px),and malondialdehyde(MDA)*** assay was used to determine the serum testosterone *** real-time PCR and Western blotting were conducted to analyze the expression of genes and proteins related to the testosterone synthesis pathway and the nuclear factor erythroid 2-related factor 2/heme oxygenase 1 antioxidant *** Oral administration of TGs induced significant increases in the testicular levels of zinc transporter 1 and MDA(P<0.05).On the other hand,sperm concentration,sperm motility,and serum testosterone,serum zinc,testicular zinc,Zrt-,Irt-like protein 1,ALP,luteinizing hormone(LH)receptor,steroidogenic acute regulatory protein,Cytochrome P450 family 11 subfamily A member 1,3β-hydroxysteroid dehydrogenase 1 T-AOC,GSH-Px,nuclear factor erythroid 2-related factor 2,heme oxygenase-1 and NAD(P)H:quinone oxidoreductase 1 levels decreased following TG

关键词： dietary supplement Jinghuosu tripterygium glycosides reproductive damage infertility

Long-term exposure to aryl hydrocarbon receptor agonist neburon induces reproductive toxicity in male zebrafish(Danio rerio)

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2024年第8期142卷 193-203页

作者： Fucong Zhang Chen Tang Yue Zhu Qian wang xin Huang Chunyan Yang Chengyong He Zhenghong zuo Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems School of Life SciencesXiamen UniversityXiamen 361102China

Neburon is a phenylurea herbicide that is widely used worldwide,but its toxicity is poorly *** our previous study,we found that neburon has strong aryl hydrocarbon receptor(AhR)agonist activity,but whether it causes reproductive toxicity is not *** the present study,zebrafish were conducted as a model organism to evaluate whether environmental concentrations of neburon(0.1,1 and 10μg/L)induce reproductive disorder in *** exposure to neburon for 150 days from embryo to adult,that the average spawning egg number in high concentration group was 106.40,which was significantly lower than 193.00in control *** result was mainly due to the abnormal male reproductive behavior caused by abnormal transcription of genes associated with reproductive behavior in the brain,such as *** proportions of spermatozoa in the medium and high concentration groups were 82.40%and 83.84%,respectively,which were significantly lower than 89.45%in control *** result was mainly caused by hormonal disturbances and an increased proportion of apoptotic *** hormonal disruption was due to the significant changes in the transcription levels of key genes in the hypothalamus-pituitary-gonadal axis following neburon *** treatment also significantly activated the AhR signaling pathway,causing oxidative stress damage and eventually leading to a significant increase in apoptosis in the exposed ***,these data filled the currently more vacant profile of neburon toxicity and might provide information to assess the ecotoxicity of neburon on male reproduction at environmentally relevant concentrations.

关键词： Zebrafish Neburon Male reproductive toxicity HPG axis AhR agonist

Comparative Analysis of Diagonal and Centrifugal Compressors with Synergy Theory in Compressed Air Energy Storage System

在线全文

学校读者我要写书评

暂无评论

Journal of Thermal Science 2024年第4期33卷 1325-1339页

作者： ZHANG Yuxin zuo Zhitao ZHOU xin GUO Wenbin CHEN Haisheng Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China National Energy Large Scale Physical Energy Storage Technologies R&D Center of Bijie Bijie551700China Nanjing Institute of Future Energy System IETCASNanjing211135China

Energy storage technology is an essential part of the efficient energy *** air energy storage(CAES)is considered to be one of the most promising large-scale physical energy storage *** is favored because of its low-cost,long-life,environmentally friendly and low-carbon *** compressor is the core component of CAES,and the performance is critical to the overall system *** importance is not only reflected in the design point,but also in the continuous efficient operation under variable working *** diagonal compressor is currently the focus of the developing large-scale CAES because of its stronger flow capacity compared with traditional centrifugal *** the diagonal compressor has the higher single stage pressure ratio compared with axial *** this paper,the full three dimensional numerical simulation technologies with synergy theory are used to compare and analyze the internal flow *** performance of the centrifugal and diagonal impellers that are optimized under the same requirements for large-scale CAES has been *** relationship between the internal flow characteristics and performance of the centrifugal and diagonal impellers with the change of mass flow rates and total inlet temperature is given qualitatively and *** the cosine value of the synergy angle is high,the local flow loss is *** smaller proportion of the positive area is the pursuit of *** comparative analysis,it is concluded that the internal flow and performance changes of centrifugal and diagonal impellers are *** results confirm the superiority and feasibility of the off-design performance of the diagonal compressor applied to the developing large-scale CAES.

关键词： compressed air energy storage synergy theory diagonal compressor centrifugal compressor comparative analysis

Detection of UAV Target Based on Continuous Radon Transform and Matched Filtering Process for Passive Bistatic Radar

在线全文

学校读者我要写书评

暂无评论

Journal of Beijing Institute of Technology 2024年第1期33卷 9-18页

作者： Luo zuo Yuefei Yan Jun wang xin Sang Yan wang Dongming Ge Lihao Ping Zhihai wang Congsi wang Guangzhou Institute of Technology Xidian UniversityGuangzhou 510555China National Laboratory of Radar Signal Processing Xidian UniversityXi’an710071China School of Information and Control Engineering Xi’an University of Architecture and TechnologyXi’anShaanxi 710055China CETC Wuhu Diamond Aircraft Manufacturing Co. LtdWuhuAnhui 241000China Beijing Space Vehicle General Design Department Beijing 100094China CETC No.38 Research Institute Hefei 230088China

Long-time integration technique is an effective way of improving target detection performance for unmanned aerial vehicle(UAV)in the passive bistatic radar(PBR),while range migration(RM)and Doppler frequency migration(DFM)may have a major effect due to the target *** paper proposed an innovative long-time coherent integration approach,regarded as Continuous Radon-matched filtering process(CRMFP),for low-observable UAV target in passive bistatic *** not only mitigates the RM by collaborative research in range and velocity dimensions but also compensates the DFM and ensures the coherent integration through the matched filtering process(MFP).Numerical and real-life data following detailed analysis verify that the proposed method can overcome the Doppler mismatch influence and acquire comparable detection performance.

关键词： passive bistatic radar unmanned aerial vehicle long-time coherent integration Radon-matched filtering process

Large eddy simulation of boundary layer combustion of hydrogen and hydrocarbon fuel films in a modeled scramjet combustor

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2024年第7期37卷 109-133页

作者： Jianfei WEI Silong ZHANG Jingying zuo xin LI Jiang QIN Wen BAO School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China

Supersonic fuel film cooling is a promising way to simultaneously reduce the severe wall heat and friction load of the internal passage in a scramjet engine when operating at hypersonic *** eddy simulations were performed to investigate the cooling and wall friction characteristics of hydrogen and hydrocarbon films under inert and reactive *** results show that the essential difference of the turbulent state in the mixing layer contributes to the totally different behaviors of the cooling and wall friction reduction performances of the two fuel *** turbulent transport processes between the hydrogen film and the mainstream are much weaker as compared to the case of hydrocarbon film,making inert hydrogen rather superior in cooling and friction reduction ***,the increase of wall temperature for hydrogen film under the inert case is mainly driven by the loss of hydrogen with high heat capacity instead of by direct heat ***,the film cooling performance severely deteriorates when the hydrogen film burns due to presence of severe heat release sources near the *** the other hand,combustion of hydrocarbon film in the boundary layer can remarkably improve its originally barely-satisfactory cooling and friction reduction performance to the level comparable to that of hydrogen film,due to the suppression of turbulent transport processes in the mixing layer and presence of heat absorption sources near the ***,the hydrogen film is more advantageous in friction reduction,while the hydrocarbon film is more suitable for cooling.

关键词： Supersonic film cooling Hydrogen Hydrocarbon Boundary layer combustion Large eddy simulation

The deleterious effects and potential therapeutic strategy of fluorene-9-bisphenol on circadian activity and liver diseases in zebrafish and mice

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2024年第11期145卷 13-27页

作者： Shuhui Zhang Xiang zuo Jialu Luan Huijuan Bai Zhenhua Fu Mingzhu Sun xin Zhao Xizeng Feng College of Life Science State Key Laboratory of Medicinal Chemical BiologyThe Key Laboratory of Bioactive MaterialsMinistry of EducationNankai UniversityTianjin 300071China Institute of Robotics&Automatic Information System College of Artificial IntelligenceNankai UniversityTianjin 300071China

Increasing evidence indicates that disturbance of the clock genes,which leads to systemic endocrine perturbation,plays a crucial role in the pathogenesis of metabolic and liver ***-9-bisphenol(BHPF)is utilized in the manufacturing of plastic materials but its biological effects on liver homeostasis remain *** impacts and involved mechanisms of BHPF on the liver diseases,metabolism,and circadian clock were comprehensively studied by zebrafish andmouse *** therapeutic effect of melatonin(MT)was also *** and mousemodels with either acute exposure(0.5 and 1μmol/L,1-4 days post-fertilization)or chronic oral exposure(0.5 and 50 mg/(kg·2 days),30 days)were established with various BHPF ***,we identified a crucial role for estrogenic regulation in liver development and circadian locomotor rhythms damaged by BHPF in a zebrafish *** mice showed chaos in circadian activity through the imbalance of circadian clock component Brain and Muscle Aryl hydrocarbon receptor nuclear translocator-like 1 in the liver and *** liver sexual dimorphic alteration alongwith reduced growth hormone and estrogens played a critical role in damaged glucose metabolism,hepatic inflammation,and fibrosis induced by ***,sleep improvement by exogenous MT alleviated BHPF-related glucose metabolism and liver injury in *** proposed the pathogenesis of metabolic and liver disease resulting from BHPF and promising targeted therapy for livermetabolism disorders associated with endocrine perturbation *** results might play a warning role in the administration of endocrine-disrupting chemicals in everyday life and various industry applications.

关键词： Fluorene-9-bisphenol(BHPF) Melatonin Circadian activity Endocrine perturbation Liver diseases Female behavior Hepatic sexual dimorphism

Employee Stock Ownership Plans and Stock-price Informativeness

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

China & World Economy 2024年第3期32卷 162-190页

作者： Yuehua zuo xin Huang Xiaojun Liu Yunhao Dai School of Economics Huazhong University of Science and TechnologyChina School of Economics and Modern Economics Research Center Huazhong University of Science and TechnologyChina

This study examines the impact of employee stock ownership plans(ESOPs)on stock-price informativeness in Chinese stock *** findings indicate that firms implementing ESOPs experienced an average 11.89 percent increase in stock-price *** plans improved stock-price informativeness through increased external attention and *** event study shows that ESOPs gave rise to an announcement effect,driven by anticipated performance improvements and the novelty associated with ESOPs.A mechanism analysis demonstrates that the implementation of ESOPs attracted market attention,and the increased market supervision resulting from this mitigated the moral hazards of management associated with *** with more positive signals exerted a greater ***,ESOPs that prioritized management incentives gained more recognition in the *** the incentive effects of ESOPs were weaker than those of equity incentive plans and the ESOPs lost novelty over time,the annual announcement effect diminished *** findings underscore the necessity of strengthening ESOP incentives for continued optimization of priceefficiency.

关键词： announcement effect corporate governance employee stock ownership plan stock-price informativeness

Fractal model of spontaneous imbibition in low-permeability reservoirs coupled with heterogeneity of pore seepage channels and threshold pressure

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Petroleum Science 2024年第2期21卷 1002-1017页

作者： Ming-Sheng zuo Hao Chen Xi-Liang Liu Hai-Peng Liu Yi Wu xin-Yu Qi National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China College of Safety and Ocean Engineering China University of Petroleum(Beijing)Beijing102249China

Spontaneous imbibition(SI)is an important mechanism for enhancing oil recovery in low-permeability *** to the strong heterogeneity,and the non-Darcy flow,the construction of SI model for lowpermeability reservoirs is extremely ***,traditional SI models based on single or averaged capillary tortuosity ignore the influence of heterogeneity of pore seepage channels and the threshold pressure(TP)on ***,in this work,based on capillary model and fractal theory,a mathematical model of characterizing SI considering heterogeneity of pore seepage channels is *** this basis,the threshold pressure was introduced to determine the pore radius at which the wetted phase can displace *** proposed new SI model was verified by imbibition experimental *** study shows that for weakly heterogeneous cores with permeability of 0-1 m D,the traditional SI model can characterize the imbibition process relatively accurately,and the new imbibition model can increase the coefficient of determination by 1.05 ***,traditional model has serious deviations in predicting the imbibition recovery for cores with permeability of 10-50 m *** new SI model coupling with heterogeneity of pore seepage channels and threshold pressure effectively solves this problem,and the determination coefficient is increased from 0.344 to 0.922,which is increased by2.68 *** low-permeability reservoirs,the production of the oil in transitional pores(0.01-0.1μm)and mesopores(0.1-1μm)significantly affects the imbibition recovery,as the research shows that when the heterogeneity of pore seepage channels is ignored,the oil recovery in transitional pores and mesopores decreases by 7.54%and 4.26%,*** analysis shows that increasing interfacial tension,decreasing contact angle,oil-water viscosity ratio and threshold pressure will increase imbibition *** addition,there are critical values for the influence of these factors o

关键词： Spontaneous imbibition Low-permeability reservoir Fractal model Threshold pressure Capillary tube