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Geological risk assessment of traffic engineering construction among 7.0-8.5 magnitude earthquake areas:Practice from the Sichuan-Tibet transport corridor in the eastern Tibetan Plateau
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作者 Ning Zhong Xian-bing Zhang +5 位作者 Chang-bao Guo Zhen Yang Hao Yu Rui-an Wu Yang Wang Hai-bing Li 《China Geology》 CAS CSCD 2024年第4期605-629,共25页
At least 13 active fault zones have developed in the Ya'an-Linzhi section of the Sichuan-Tibet transport corridor,and there have been undergone 17 MS≥7.0 earthquakes,the largest earthquake is 1950 Chayu MS 8.5 ea... At least 13 active fault zones have developed in the Ya'an-Linzhi section of the Sichuan-Tibet transport corridor,and there have been undergone 17 MS≥7.0 earthquakes,the largest earthquake is 1950 Chayu MS 8.5 earthquake,which has very strong seismic activity.Therefore,carrying out engineering construction in the Sichuan-Tibet transport corridor is a huge challenge for geological technological personnel.To determining the spatial geometric distribution,activity of active faults and geological safety risk in the Sichuan-Tibet transport corridor.Based on remote sensing images,ground surveys,and chronological tests,as well as the deep geophysical and current GPS data,we investigated the geometry,segmentation,and paleoearthquake history of five major active fault zones in the Ya'an-Linzhi section of the Sichuan-Tibet transport corridor,namely the Xianshuihe,Litang,Batang,Jiali-Chayu and Lulang-Yigong.The five major fault zones are all Holocene active faults,which contain strike-slip components as well as thrust or normal fault components,and contain multiple branch faults.The Selaha-Kangding segment of the Xianshuihe fault zone,the Maoyaba and Litang segment of the Litang fault zone,the middle segment(Yigong-Tongmai-Bomi)of Jiali-Chayu fault zone and Lulang-Yigong fault zone have the risk of experiencing strong earthquakes in the future,with a high possibility of the occurrence of MS≥7.0 earthquakes.The Jinsha River and the Palong-Zangbu River,which is a high-risk area for geological hazard chain risk in the Ya'an-Linzhi section of the Sichuan-Tibet transport corridor.Construction and safe operation Ya'an-Linzhi section of the Sichuan-Tibet transport corridor,need strengthen analysis the current crustal deformation,stress distribution and fault activity patterns,clarify active faults relationship with large earthquakes,and determine the potential maximum magnitude,epicenters,and risk range.This study provides basic data for understanding the activity,seismicity,and tectonic deformation patterns of the regional faults in the Sichuan-Tibet transport corridor. 展开更多
关键词 Earthquake belt Active fault PALEOEARTHQUAKE Seismicity Earthquake landslide Sichuan-Tibet transport corridor Tectonic deformation pattern Stress distribution Geological disater survey engineering Remote sensing survey
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Optimizing electronic structure through point defect engineering for enhanced electrocatalytic energy conversion
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作者 Wei Ma Jiahao Yao +6 位作者 Fang Xie Xinqi Wang Hao Wan Xiangjian Shen Lili Zhang Menggai Jiao Zhen Zhou 《Green Energy & Environment》 SCIE EI CAS 2025年第1期109-131,共23页
Point defect engineering endows catalysts with novel physical and chemical properties,elevating their electrocatalytic efficiency.The introduction of defects emerges as a promising strategy,effectively modifying the e... Point defect engineering endows catalysts with novel physical and chemical properties,elevating their electrocatalytic efficiency.The introduction of defects emerges as a promising strategy,effectively modifying the electronic structure of active sites.This optimization influences the adsorption energy of intermediates,thereby mitigating reaction energy barriers,altering paths,enhancing selectivity,and ultimately improving the catalytic efficiency of electrocatalysts.To elucidate the impact of defects on the electrocatalytic process,we comprehensively outline the roles of various point defects,their synthetic methodologies,and characterization techniques.Importantly,we consolidate insights into the relationship between point defects and catalytic activity for hydrogen/oxygen evolution and CO_(2)/O_(2)/N_(2) reduction reactions by integrating mechanisms from diverse reactions.This underscores the pivotal role of point defects in enhancing catalytic performance.At last,the principal challenges and prospects associated with point defects in current electrocatalysts are proposed,emphasizing their role in advancing the efficiency of electrochemical energy storage and conversion materials. 展开更多
关键词 Point defect engineering DOPING VACANCY ELECTROCATALYSIS Electronic structure
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Morphology engineering of ZnO micro/nanostructures under mild conditions for optoelectronic application
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作者 Liang Chu Haoyu Shen +3 位作者 Hudie Wei Hongyu Chen Guoqiang Ma Wensheng Yan 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第2期498-503,共6页
Zinc oxide(ZnO)serves as a crucial functional semiconductor with a wide direct bandgap of approximately 3.37 eV.Solvothermal reaction is commonly used in the synthesis of ZnO micro/nanostructures,given its low cost,si... Zinc oxide(ZnO)serves as a crucial functional semiconductor with a wide direct bandgap of approximately 3.37 eV.Solvothermal reaction is commonly used in the synthesis of ZnO micro/nanostructures,given its low cost,simplicity,and easy implementation.Moreover,ZnO morphology engineering has become desirable through the alteration of minor conditions in the reaction process,particularly at room temperature.In this work,ZnO micro/nanostructures were synthesized in a solution by varying the amounts of the ammonia added at low temperatures(including room temperature).The formation of Zn^(2+)complexes by ammonia in the precursor regulated the reaction rate of the morphology engineering of ZnO,which resulted in various structures,such as nanoparticles,nanosheets,microflowers,and single crystals.Finally,the obtained ZnO was used in the optoelectronic application of ultraviolet detectors. 展开更多
关键词 morphology engineering low temperature ZnO nanosheets microflowers ultraviolet detector
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Defect Engineering with Rational Dopants Modulation for High‑Temperature Energy Harvesting in Lead‑Free Piezoceramics
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作者 Kaibiao Xi Jianzhe Guo +2 位作者 Mupeng Zheng Mankang Zhu Yudong Hou 《Nano-Micro Letters》 SCIE EI CAS 2025年第3期87-101,共15页
High temperature piezoelectric energy harvester(HTPEH)is an important solution to replace chemical battery to achieve independent power supply of HT wireless sensors.However,simultaneously excellent performances,inclu... High temperature piezoelectric energy harvester(HTPEH)is an important solution to replace chemical battery to achieve independent power supply of HT wireless sensors.However,simultaneously excellent performances,including high figure of merit(FOM),insulation resistivity(ρ)and depolarization temperature(Td)are indispensable but hard to achieve in lead-free piezoceramics,especially operating at 250°C has not been reported before.Herein,well-balanced performances are achieved in BiFeO3–BaTiO3 ceramics via innovative defect engineering with respect to delicate manganese doping.Due to the synergistic effect of enhancing electrostrictive coefficient by polarization configuration optimization,regulating iron ion oxidation state by high valence manganese ion and stabilizing domain orientation by defect dipole,comprehensive excellent electrical performances(Td=340°C,ρ250°C>10^(7)Ωcm and FOM_(250°C)=4905×10^(–15)m^(2)N^(−1))are realized at the solid solubility limit of manganese ions.The HT-PEHs assembled using the rationally designed piezoceramic can allow for fast charging of commercial electrolytic capacitor at 250°C with high energy conversion efficiency(η=11.43%).These characteristics demonstrate that defect engineering tailored BF-BT can satisfy high-end HT-PEHs requirements,paving a new way in developing selfpowered wireless sensors working in HT environments. 展开更多
关键词 Lead-free piezoceramic Defect engineering Dopants modulation High-temperature Piezoelectric energy harvester
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Defect Engineering:Can it Mitigate Strong Coulomb Effect of Mg^(2+)in Cathode Materials for Rechargeable Magnesium Batteries?
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作者 Zhengqing Fan Ruimin Li +3 位作者 Xin Zhang Wanyu Zhao Zhenghui Pan Xiaowei Yang 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期135-159,共25页
Rechargeable magnesium batteries(RMBs)have been considered a promising“post lithium-ion battery”system to meet the rapidly increasing demand of the emerging electric vehicle and grid energy storage market.However,th... Rechargeable magnesium batteries(RMBs)have been considered a promising“post lithium-ion battery”system to meet the rapidly increasing demand of the emerging electric vehicle and grid energy storage market.However,the sluggish diffusion kinetics of bivalent Mg^(2+)in the host material,related to the strong Coulomb effect between Mg^(2+)and host anion lattices,hinders their further development toward practical applications.Defect engineering,regarded as an effective strategy to break through the slow migration puzzle,has been validated in various cathode materials for RMBs.In this review,we first thoroughly understand the intrinsic mechanism of Mg^(2+)diffusion in cathode materials,from which the key factors affecting ion diffusion are further presented.Then,the positive effects of purposely introduced defects,including vacancy and doping,and the corresponding strategies for introducing various defects are discussed.The applications of defect engineering in cathode materials for RMBs with advanced electrochemical properties are also summarized.Finally,the existing challenges and future perspectives of defect engineering in cathode materials for the overall high-performance RMBs are described. 展开更多
关键词 Rechargeable magnesium battery Sluggish diffusion kinetic Defect engineering Cathode materials Ion migration
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Teaching Reform of Environmental Engineering Microbiology Based on OBE Concept in the Context of New Engineering Disciplines
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作者 Shasha LIU Jinhuan DENG Weixiong LIN 《Asian Agricultural Research》 2025年第1期41-43,共3页
In response to meeting the needs of cultivating applied talents in the construction of new engineering disciplines,based on the concept of Outcome-Based Education(OBE),this study analyzes the problems existing in the ... In response to meeting the needs of cultivating applied talents in the construction of new engineering disciplines,based on the concept of Outcome-Based Education(OBE),this study analyzes the problems existing in the teaching of the course Environmental Engineering Microbiology,and put forward some corresponding curriculum reform schemes.According to the target points of professional graduation requirements,the scheme proposes revising the syllabus of Environmental Engineering Microbiology,clarifying the curriculum objectives,updating the teaching content,and reforming the teaching methods.Through these measures,it is intended to achieve the unity of teachers way of"teaching"and students way of"learning",construct a new teaching mode,fully stimulate students subjective initiative,and enhance students innovative consciousness and practical ability.Besides,in this study,a"whole process-diversification"evaluation system is established to comprehensively evaluate students performance in theoretical knowledge learning and practical application,comprehensively evaluate students learning situation,and analyze the teaching effect in real time,so as to achieve continuous improvement,and ultimately achieve the goal of improving classroom quality. 展开更多
关键词 New engineering disciplines Outcome-Based Education(OBE)concept Environmental engineering Microbiology
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Risk Management Techniques in Construction Projects:Development and Assessment of an Innovative
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作者 Ahmed Ali Khatatbeh 《Journal of Civil Engineering and Architecture》 2025年第1期1-8,共8页
Professional and trade skills are required for handling the construction related projects;Construction industries of the present day however lack useful information concerning different practices,patterns and trends i... Professional and trade skills are required for handling the construction related projects;Construction industries of the present day however lack useful information concerning different practices,patterns and trends involved in risk management.Considering this,the present study focuses on the aforementioned variables of risk management by quantitative analysis specifically in the domain of construction industry.This study has used IBM’s SPSS(Statistical Package for Social Sciences)version 25.0 to analyze the results.This study is an initiative to assess the impact of risk management in the construction sector of Jordan.It will assist the construction sector for exploring the limitations with respect to integrate effective risk management.A sense of competition will be developed through a comparison of risk factors of construction projects among the project stakeholders such as contractors should enhance their risk management practices. 展开更多
关键词 CONSTRUCTION Jordanian construction projects risk assessment risk treatment
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Characterization and correlation of engineering properties with microstructure in peanuts:A microscopic to macroscopic analysis
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作者 Fei Xiang Zhenyuan Li +9 位作者 Yichen Zheng Caixia Ding Benu Adhikari Xiaojie Ma Xuebing Xu Jinjin Zhu Bello Zaki Abubakar Aimin Shi Hui Hu Qiang Wang 《Journal of Integrative Agriculture》 2025年第1期339-352,共14页
Peanut varieties are diverse globally,with their characters and nutrition determining the product quality.However,the comparative analysis and statistical analysis of key quality indicators for peanut kernels across t... Peanut varieties are diverse globally,with their characters and nutrition determining the product quality.However,the comparative analysis and statistical analysis of key quality indicators for peanut kernels across the world remains relatively limited,impeding the comprehensive evaluation of peanut quality and hindering the industry development on a global scale.This study aimed to compare and analyze the apparent morphology,microstructure,single-cell structure,engineering and mechanical properties,as well as major nutrient contents of peanut kernels from 10 different cultivars representing major peanut-producing countries.The surface and cross-section microstructure of the peanut kernels exhibited a dense“blocky”appearance with a distinct cellular structure.The lipid droplets were predominantly spherical with a regular distribution within the cells.The single-cell structure of the kernels from these 10 peanut cultivars demonstrated varying morphologies and dimensions,which exhibited correlations with their mechanical and engineering properties.Furthermore,the mass loss versus temperature profiles of the peanut kernels revealed five distinct stages,corresponding to moisture loss,volatile loss,protein denaturation,and the degradation of various biomacromolecules.Variations were also observed in the lipid,protein,and sucrose contents,texture,bulk density,true density,porosity,geometric mean diameter,and sphericity among the diferent peanut varieties.This study establishes relationships and correlations among microstructure,engineering properties,and nutritional composition of commonly grown peanut varieties in major peanut-processing countries.The findings provide valuable insights into peanut quality evaluation,empowering the peanut industry to enhance their processing and product development efforts. 展开更多
关键词 peanut kernels apparent morphology MICROSTRUCTURE engineering properties mechanical properties
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An integrated approach for GLOF hazard,vulnerability and risk assessment in the Karakoram Mountain Range of northern Pakistan
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作者 Sajid ULLAH Muhammad SHAFIQUE +2 位作者 Ghazanfar Ali KHATTAK Attaullah SHAH Yaseen ULLAH 《Journal of Mountain Science》 2025年第1期142-155,共14页
Climate change and rising temperatures are accelerating the rate of deglaciation in the Hindu Kush Karakoram Himalaya(HKH)ranges,leading to the formation of new glacial lakes and the expansion of existing ones.These l... Climate change and rising temperatures are accelerating the rate of deglaciation in the Hindu Kush Karakoram Himalaya(HKH)ranges,leading to the formation of new glacial lakes and the expansion of existing ones.These lakes are often vulnerable to failure,posing a significant threat to downstream communities and infrastructure.Therefore,a comprehensive assessment of Glacier-Lake Outburst Flood(GLOF)hazards and risk assessment is crucial to evaluate flood runout characteristics and identify settlements and infrastructure that are exposed and vulnerable to floods,aiding in the development and implementation of risk reduction strategies.This study aims to simulate a GLOF event induced by the Shisper glacier lake in northern Pakistan,using the HEC-RAS,and to assess its impact on settlements,infrastructure,and agricultural land.For the hydrometeorological analysis of the GLOF event,topographic data from unmanned aerial vehicles(UAVs),stream profiles,discharge data,Manning's roughness coefficient(n),and land use/land cover(LULC)were analyzed using HEC-RAS and geographic information system(GIS).During the GLOF event on May 7,2022,a maximum water depth of 6.3 m and a maximum velocity of 9.5 m/s were recorded.Based on the runout characteristics of this event,vulnerability and risk assessments have been calculated.The physical,social,and environmental vulnerabilities of the at-risk elements were evaluated using the analytical hierarchy process(AHP)and integrated with the hazard data to develop a risk map.The study identified the areas,infrastructure and settlements susceptible to GLOF hazard to support the development and implementation of targeted and evidence-based mitigation and adaptation strategies. 展开更多
关键词 GLOF Hazard assessment Glacial lake HEC-RAS Vulnerability and risk Shisper glacier
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Do Child–Turcotte–Pugh and nutritional assessments predict survival in cirrhosis: A longitudinal study
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作者 Randhall B Carteri Claudio A Marroni +4 位作者 Luis F Ferreira Letícia P Pinto Juliana Czermainski Cristiane V Tovo Sabrina A Fernandes 《World Journal of Hepatology》 2025年第1期29-40,共12页
BACKGROUND Cirrhotic patients face heightened energy demands,leading to rapid glycogen depletion,protein degradation,oxidative stress,and inflammation,which drive disease progression and complications.These disruption... BACKGROUND Cirrhotic patients face heightened energy demands,leading to rapid glycogen depletion,protein degradation,oxidative stress,and inflammation,which drive disease progression and complications.These disruptions cause cellular damage and parenchymal changes,resulting in vascular alterations,portal hypertension,and liver dysfunction,significantly affecting patient prognosis.AIM To analyze the association between Child–Turcotte–Pugh(CTP)scores and di-fferent nutritional indicators with survival in a 15-year follow-up cohort.METHODS This was a retrospective cohort study with 129 cirrhotic patients of both sexes aged>18 years.Diagnosis of cirrhosis was made by liver biopsy.The first year of data collection was 2007,and data regarding outcomes were collected in 2023.Data were gathered from medical records,and grouped by different methods,including CTP,handgrip strength,and triceps skinfold cutoffs.The prognostic values for mortality were assessed using Kaplan–Meier curves and multivariate binary logistic regression models.RESULTS The coefficient for CTP was the only statistically significant variable(Wald=5.193,P=0.023).This suggests that with a negative change in CTP classification score,the odds of survival decrease 52.6%.The other evaluated variables did not significantly predict survival outcomes in the model.Kaplan–Meier survival curves also indicated that CTP classification was the only significant predictor.CONCLUSION Although different classifications showed specific differences in stratification,only CTP showed significant predictive potential.CTP score remains a simple and effective predictive tool for cirrhotic patients even after longer follow-up. 展开更多
关键词 Liver cirrhosis Child–Turcotte–Pugh PROGNOSIS Liver transplantation Nutritional assessment
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From earthquake resistance structure to earthquake resilience city–urban seismic resilience assessment
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作者 Xie Lili Zhao Yonggang +1 位作者 Wen Weiping Zhai Changhai 《Earthquake Engineering and Engineering Vibration》 2025年第1期1-13,共13页
Earthquakes pose significant perils to the built environment in urban areas.To avert the calamitous aftermath of earthquakes,it is imperative to construct seismic resilient cities.Due to the intricacy of the concept o... Earthquakes pose significant perils to the built environment in urban areas.To avert the calamitous aftermath of earthquakes,it is imperative to construct seismic resilient cities.Due to the intricacy of the concept of urban seismic resilience(USR),its assessment is a large-scale system engineering issue.The assessment of USR should be based on the notion of urban seismic capacity(USC)assessment,which includes casualties,economic loss,and recovery time as criteria.Functionality loss is also included in the assessment of USR in addition to these criteria.The assessment indicator system comprising five dimensions(building and lifeline infrastructure,environment,society,economy,and institution)and 20 indicators has been devised to quantify USR.The analytical hierarchy process(AHP)is utilized to compute the weights of the criteria,dimensions,and indicators in the urban seismic resilience assessment(USRA)indicator system.When the necessary data for a city are obtainable,the seismic resilience of that city can be assessed using this framework.To illustrate the proposed methodology,a moderate-sized city in China was selected as a case study.The assessment results indicate a high level of USR,suggesting that the city possesses strong capabilities to withstand and recover from potential future earthquakes. 展开更多
关键词 urban seismic capacity urban seismic resilience assessment analytic hierarchy process functionality loss
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Vibration safety assessment and parameter analysis of buried oil pipelines based on vibration isolation holes under strong surface impact
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作者 Wang Guobo Mei Hua +4 位作者 Wang Jianning He Wei Yin Yao Zhai Yuxin Zuo Pengfei 《Earthquake Engineering and Engineering Vibration》 2025年第1期69-82,共14页
Strong surface impact will produce strong vibration,which will pose a threat to the safety of nearby buried pipelines and other important lifeline projects.Based on the verified numerical method,a comprehensive numeri... Strong surface impact will produce strong vibration,which will pose a threat to the safety of nearby buried pipelines and other important lifeline projects.Based on the verified numerical method,a comprehensive numerical parameter analysis is conducted on the key influencing factors of the vibration isolation hole(VIH),which include hole diameter,hole net spacing,hole depth,hole number,hole arrangement,and soil parameters.The results indicate that a smaller ratio of net spacing to hole diameter,the deeper the hole,the multi-row hole,the hole adoption of staggered arrangements,and better site soil conditions can enhance the efficiency of the VIH barrier.The average maximum vibration reduction efficiency within the vibration isolation area can reach 42.2%.The vibration safety of adjacent oil pipelines during a dynamic compaction projection was evaluated according to existing standards,and the measurement of the VIH was recommended to reduce excessive vibration.The single-row vibration isolation scheme and three-row staggered arrangement with the same hole parameters are suggested according to different cases.The research findings can serve as a reference for the vibration safety analysis,assessment,and control of adjacent underground facilities under the influence of strong surface impact loads. 展开更多
关键词 vibration isolation hole buried oil pipeline strong surface impact vibration velocity vibration safety assessment
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Assessment of the hip-spine relationship in total hip arthroplasty for childhood hip disorders sequelae
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作者 Cong-Ke Shu Hai-Song Liang +2 位作者 Xin-Wen Bai Yu Deng Qi-Long Jiang 《World Journal of Orthopedics》 2025年第1期86-88,共3页
In this article,we comment on the article by Oommen et al.Oommen et al provided a comprehensive overview of the management of hip centre restoration in total hip arthroplasty(THA)for childhood hip disorder sequelae.Gi... In this article,we comment on the article by Oommen et al.Oommen et al provided a comprehensive overview of the management of hip centre restoration in total hip arthroplasty(THA)for childhood hip disorder sequelae.Given the developmental disparity in this population,specific preoperative planning is an essential prerequisite for the success of THA procedures.In the review by Oommen et al,assessments of acetabular and femoral anatomic variations were fully described.However,spinal malalignment and stiffness are common in physical and radiological examinations and should be taken into careful consideration when planning surgical procedures.Poor outcomes of THA for patients with comorbid hip and spinopelvic pathologies have been widely reported,especially for hips with childhood disorder sequelae.Therefore,in this editorial,we would like to emphasize the need for a thorough hip-spine evaluation of patients with childhood hip disorder sequelae before THA. 展开更多
关键词 Relationship between the hip and spine Total hip arthroplasty Childhood disorder sequelae Preoperative assessment Hip-spine classification
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Vulnerability assessment of UAV engine to laser based on improved shotline method
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作者 Le Liu Chengyang Xu +3 位作者 Changbin Zheng Sheng Cai Chunrui Wang Jin Guo 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期588-600,共13页
Laser anti-drone technology is entering the sequence of actual combat,and it is necessary to consider the vulnerability of typical functional parts of UAVs.Since the concept of"vulnerability"was proposed,a v... Laser anti-drone technology is entering the sequence of actual combat,and it is necessary to consider the vulnerability of typical functional parts of UAVs.Since the concept of"vulnerability"was proposed,a variety of analysis programs for battlefield targets to traditional weapons have been developed,but a comprehensive assessment methodology for targets'vulnerability to laser is still missing.Based on the shotline method,this paper proposes a method that equates laser beam to shotline array,an efficient vulnerability analysis program of target to laser is established by this method,and the program includes the circuit board and the wire into the vulnerability analysis category,which improves the precision of the vulnerability analysis.Taking the UAV engine part as the target of vulnerability analysis,combine with the"life-death unit method"to calculate the laser penetration rate of various materials of the UAV,and the influence of laser weapon system parameters and striking orientation on the killing probability is quantified after introducing the penetration rate into the vulnerability analysis program.The quantitative analysis method proposed in this paper has certain general expansibility,which can provide a fresh idea for the vulnerability analysis of other targets to laser. 展开更多
关键词 Laser weapon Laser damage VULNERABILITY UAV enginE Killing probability
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Rapid post-earthquake safety assessment of low-rise reinforced concrete structures
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作者 Koji Tsuchimoto Yasutaka Narazaki Billie F.Spencer,Jr. 《Earthquake Engineering and Engineering Vibration》 2025年第1期101-112,共12页
Many countries throughout the world have experienced large earthquakes,which cause building damage or collapse.After such earthquakes,structures must be inspected rapidly to judge whether they are safe to reoccupy.To ... Many countries throughout the world have experienced large earthquakes,which cause building damage or collapse.After such earthquakes,structures must be inspected rapidly to judge whether they are safe to reoccupy.To facilitate the inspection process,the authors previously developed a rapid building safety assessment system using sparse acceleration measurements for steel framed buildings.The proposed system modeled nonlinearity in the measurement data using a calibrated simplified lumped-mass model and convolutional neural networks(CNNs),based on which the buildinglevel damage index was estimated rapidly after earthquakes.The proposed system was validated for a nonlinear 3D numerical model of a five-story steel building,and later for a large-scale specimen of an 18-story building in Japan tested on the E-Defense shaking table.However,the applicability of the safety assessment system for reinforced concrete(RC)structures with complex hysteretic material nonlinearity has yet to be explored;the previous approach based on a simplified lumpedmass model with a Bouc-Wen hysteretic model does not accurately represent the inherent nonlinear behavior and resulting damage states of RC structures.This study extends the rapid building safety assessment system to low-rise RC moment resisting frame structures representing typical residential apartments in Japan.First,a safety classification for RC structures based on a damage index consistent with the current state of practice is defined.Then,a 3D nonlinear numerical model of a two-story moment frame structure is created.A simplified lumped-mass nonlinear model is developed and calibrated using the 3D model,incorporating the Takeda degradation model for the RC material nonlinearity.This model is used to simulate the seismic response and associated damage sensitive features(DSF)for random ground motion.The resulting database of responses is used to train a convolutional neural network(CNN)that performs rapid safety assessment.The developed system is validated using the 3D nonlinear analysis model subjected to historical earthquakes.The results indicate the applicability of the proposed system for RC structures following seismic events. 展开更多
关键词 rapid post-earthquake safety assessment ACCELERATION interstory drift angle damage sensitive feature convolutional neural network RC structure simplified non-linear analysis model Takeda degradation model
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TDFAD APPROACH TO HIGH TEMPERATURE DEFECT ASSESSMENT AND ITS ENGINEERING APPLICATION 被引量:4
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作者 XuanFuzhen TuShandong WangZhengdong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2004年第4期537-542,共6页
From the idea of failure of defective structures at high temperature beingcontrolled by two mechanisms: fast fracture due to creep crack growth initiating at the crack tipand creep rupture on the weakened section, a t... From the idea of failure of defective structures at high temperature beingcontrolled by two mechanisms: fast fracture due to creep crack growth initiating at the crack tipand creep rupture on the weakened section, a time-dependent failure assessment diagram (TDFAD) isdeveloped on the basis of the time dependent crack tip parameter J integral. According to theproposed TDFAD method, detailed crack initiation and creep crack growth analysis is avoided insafety assessments of high temperature structures by performing simple calculations of stressintensity factor and limit load. To evaluate the creep toughness parameter K_(mat), three differentexpressions are suggested on the basis of experimental load-line displacement, creep crackinitiation and growth parameters as well as the isochronous stress-strain curve. The influence ofservice factors such as temperature and service-time on the proposed TDFAD is discussed by using theproperties of 2.25CrlMo steel and an example is also presented to illustrate the approach. 展开更多
关键词 Defective structure Safety assessment CREEP High temperature Time-dependent failure assessment diagram
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Risk assessment and management in underground rock engineering——an overview 被引量:2
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作者 Edwin T Brown 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE 2012年第3期193-204,共12页
This paper attempts to provide an overview of risk assessment and management practice in underground rock engineering based on a review of the international literature and some personal experience. It is noted that th... This paper attempts to provide an overview of risk assessment and management practice in underground rock engineering based on a review of the international literature and some personal experience. It is noted that the terminologies used in risk assessment and management studies may vary from country to country. Probabilistic risk analysis is probably the most widely-used approach to risk assessment in rock engineering and in geotechnical engineering more broadly. It is concluded that great potential exists to augment the existing probabilistic methods by the use of Bayesian networks and decision analysis techniques to allow reasoning under uncertainty and to update probabilities, material properties and analyses as further data become available throughout the various stages of a project. Examples are given of the use of these methods in underground excavation engineering in China and elsewhere, and opportunities for their further application are identified. 展开更多
关键词 Bayesian networks probabilistic risk analysis risk analysis risk management underground rock engineering
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Role of bioengineering structures made of willow cuttings in marly sediment trapping: assessment of three real-size experiments in the Southern French Alps 被引量:1
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作者 Freddy REY 《Journal of Mountain Science》 SCIE CSCD 2018年第2期225-236,共12页
Improving knowledge on the ability of bioengineering structures made of willow cuttings to enhance efficient and sustainable sediment trapping in marly gullies in the Southern French Alps under a mountainous Mediterra... Improving knowledge on the ability of bioengineering structures made of willow cuttings to enhance efficient and sustainable sediment trapping in marly gullies in the Southern French Alps under a mountainous Mediterranean climate, to decreasesediment trapped per experiment, the mean annual values reached 0.25, 0.14 and 0.08 m3 yr-1 in experiments C, A and B, respectively. Maximum values for one structure reached 1.94 m3 per year in experiment C. The significance of the volumes ofsediment yield at their outlets, is a key issue today for the international scientific community working in geosciences and ecology. This study therefore aims to assess three real-size experiments(A, B and C) carried out between 2003 and 2013 in this environment. A total of 157 bioengineering structures using purple and white willow(Salix purpurea and Salix incana)cuttings – which have been shown to resprout and survive more than 2 years after their installation,corresponding to brush layers with brush mats on wooden sills(BLM), 1.2 m wide and 2 m long,installed on the floors of 33 experimental marly gullies, were monitored. The results showed that sediment trapping occurred upstream of the vegetation barriers from the 1 st year onwards.Considering the depth of sediment trapped per experiment, the mean annual values reached 11.2 cm yr-1 after 3 years in experiment A, 7.7 cm yr-1 after 2–4 years in experiment C and 5.1 cm yr-1 after 5 years in experiment B. Occasionally, BLMs showed that they could trap up to 16 and 15 cm yr-1 in experiments A and C, respectively. Considering the volumes oftrapped sediment and the sustainability of sediment trapping are discussed, and rules for bioengineering strategies are proposed. 展开更多
关键词 Erosion Marly gully Vegetation barriers Ecological engineering SALIX
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THE RISK ASSESSMENT OF THE LONG-DISTANCE OILPIPELINE ENGINEERING
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作者 Wang Jinghua Mu Congru(Institute of Geography, CAS, Beijing 100101People’s Republic of China) 《Journal of Geographical Sciences》 SCIE CSCD 1996年第1期78-83,共6页
The oilfield construction and long-distance oil pipeline engineering has been developed extensively in China. The risk assessment of oil industry will, however, be an important objective to cope with the development o... The oilfield construction and long-distance oil pipeline engineering has been developed extensively in China. The risk assessment of oil industry will, however, be an important objective to cope with the development of oil industry , The risk assessment of oil industry has many subjects worthy to be studied.The major purpose of the paper is to research the risk cases of long-distance oil pipeline engineering in Ganshu and Shaanxi provinces. 展开更多
关键词 long-distance oil pipeline risk assessment engineering GANSU SHAANXI
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Engineering critical assessment on welding flaws of the X65 UOE girth weld based on CRACKWISE
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作者 WANG Huailong QIAN Weifang 《Baosteel Technical Research》 CAS 2017年第3期36-42,共7页
Focused on the girth weld of a φ762 x 28.6 mm (X65) offshore UOE pipe, the fracture toughness properties at different weld joint positions were tested. Meanwhile,the largest size of different cracks under service c... Focused on the girth weld of a φ762 x 28.6 mm (X65) offshore UOE pipe, the fracture toughness properties at different weld joint positions were tested. Meanwhile,the largest size of different cracks under service condition was calculated by using CRACKWISE. The service life of the UOE pipe with postulated crack-like flaws was calculated by considering various fatigue factors, such as vibrations caused by ocean current and fluctuations of inner pressure. The assessment process and results can be used to direct the repair of weld flaws laid in pipes or to assess the reliability of in-serving pipes. 展开更多
关键词 engineering critical assessment fracture toughness crack tip opening displacement(CTOD) UOE pipe
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