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Analysis of Chemical Research Progress on Graphene
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作者 Xiaoming Cheng Haiyang Bian Ye Ju 《Expert Review of Chinese Chemical》 2024年第1期34-35,共2页
Graphene materials have excellent optical and electrical properties,and in recent years,significant achievements have been made in the chemical improvement and preparation of graphene.This article analyzes the progres... Graphene materials have excellent optical and electrical properties,and in recent years,significant achievements have been made in the chemical improvement and preparation of graphene.This article analyzes the progress in the chemical preparation,chemical modification,surface chemistry,and catalysis of graphene,in order to provide reference for relevant personnel. 展开更多
关键词 GRAPHENE chemical research progress analysis
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Stylistic Analysis on English On-line Chat
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作者 别尽秋 闻扬波 《海外英语》 2013年第6X期224-225,227,共3页
Based on the fact that on-line chat has become the most developing language form in the information age, this article point out the stylistic features of on-line English chat. Though in written language form, such lan... Based on the fact that on-line chat has become the most developing language form in the information age, this article point out the stylistic features of on-line English chat. Though in written language form, such language is spoken language in nature, thus it is worthwhile to analyze this special phaenomenon in lexical and grammatical level. 展开更多
关键词 on-line ENGLISH STYLISTIC analysis LEXICAL grammat
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On-line Batch Process Monitoring and Diagnosing Based on Fisher Discriminant Analysis
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作者 赵旭 邵惠鹤 《Journal of Shanghai Jiaotong university(Science)》 EI 2006年第3期307-312,316,共7页
A new on-line batch process monitoring and diagnosing approach based on Fisher discriminant analysis (FDA) was proposed. This method does not need to predict the future observations of variables, so it is more sensi... A new on-line batch process monitoring and diagnosing approach based on Fisher discriminant analysis (FDA) was proposed. This method does not need to predict the future observations of variables, so it is more sensitive to fault detection and stronger implement for monitoring. In order to improve the monitoring performance, the variables trajectories of batch process are separated into several blocks. The key to the proposed approach for on-line monitoring is to calculate the distance of block data that project to low-dimension Fisher space between new batch and reference batch. Comparing the distance with the predefine threshold, it can be considered whether the batch process is normal or abnormal. Fault diagnosis is performed based on the weights in fault direction calculated by FDA. The proposed method was applied to the simulation model of fed-batch penicillin fermentation and the resuits were compared with those obtained using MPCA. The simulation results clearly show that the on-line monitoring method based on FDA is more efficient than the MPCA. 展开更多
关键词 batch process on-line process monitoring fault diagnosis Fisher discriminant analysis (FDA) multiway principal component analysis (MPCA)
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Mechanics Analysis of Overhead Transmission Lines Based On-line Monitoring
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作者 Lili Dai Yongli Zhu Zehui Liang 《Open Journal of Applied Sciences》 2013年第2期1-4,共4页
At present, the on-line monitoring is widely applied to the power line monitoring. In this paper, a new mechanical calculation model is established according to the on-line monitoring. And this model is based on the p... At present, the on-line monitoring is widely applied to the power line monitoring. In this paper, a new mechanical calculation model is established according to the on-line monitoring. And this model is based on the parameters that tension sensors and angle sensors on suspended points detect, and combines with the parameters of the wire itself, and also considers the deflection angel of wires due to wind. In this model, mechanics parameters of wires are turned into the new coordinate plane after deflection angel of wires due to wind, or windage yaw plane. A statics tension balance equation is built in the vertical direction of the new windage yaw plane. According to the theoretical analysis and algorithm, we verify the accuracy of this newly developed mechanical calculation model. 展开更多
关键词 OVERHEAD Transmission Line on-line Monitoring Mechanical analysis Tension ANGLE ICING Windage Yaw
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Bioinformatics analysis of ferroptosis in spinal cord injury 被引量:10
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作者 Jin-Ze Li Bao-You Fan +8 位作者 Tao Sun Xiao-Xiong Wang Jun-Jin Li Jian-Ping Zhang Guang-Jin Gu Wen-Yuan Shen De-Rong Liu Zhi-Jian Wei Shi-Qing Feng 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第3期626-633,共8页
Ferroptosis plays a key role in aggravating the progression of spinal cord injury(SCI),but the specific mechanism remains unknown.In this study,we constructed a rat model of T10 SCI using a modified Allen method.We id... Ferroptosis plays a key role in aggravating the progression of spinal cord injury(SCI),but the specific mechanism remains unknown.In this study,we constructed a rat model of T10 SCI using a modified Allen method.We identified 48,44,and 27 ferroptosis genes that were differentially expressed at 1,3,and 7 days after SCI induction.Compared with the sham group and other SCI subgroups,the subgroup at 1 day after SCI showed increased expression of the ferroptosis marker acyl-CoA synthetase long-chain family member 4 and the oxidative stress marker malondialdehyde in the injured spinal cord while glutathione in the injured spinal cord was lower.These findings with our bioinformatics results suggested that 1 day after SCI was the important period of ferroptosis progression.Bioinformatics analysis identified the following top ten hub ferroptosis genes in the subgroup at 1 day after SCI:STAT3,JUN,TLR4,ATF3,HMOX1,MAPK1,MAPK9,PTGS2,VEGFA,and RELA.Real-time polymerase chain reaction on rat spinal cord tissue confirmed that STAT3,JUN,TLR4,ATF3,HMOX1,PTGS2,and RELA mRNA levels were up-regulated and VEGFA,MAPK1 and MAPK9 mRNA levels were down-regulated.Ten potential compounds were predicted using the DSigDB database as potential drugs or molecules targeting ferroptosis to repair SCI.We also constructed a ferroptosis-related mRNA-miRNA-lncRNA network in SCI that included 66 lncRNAs,10 miRNAs,and 12 genes.Our results help further the understanding of the mechanism underlying ferroptosis in SCI. 展开更多
关键词 bioinformatics drug ferroptosis Gene Ontology enrichment analysis gene-miRNA network Kyoto Encyclopedia of Genes and Genomes pathway mRNA-miRNA-lncRNA network progression spinal cord injury
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Methods for Progressive Collapse Analysis of Building Structures Under Blast and Impact Loads 被引量:5
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作者 李忠献 师燕超 《Transactions of Tianjin University》 EI CAS 2008年第5期329-339,共11页
Progressive collapse of building structures under blast and impact loads has attracted great attention all over the world. Progressive collapse analysis is essential for an economic and safe design of building structu... Progressive collapse of building structures under blast and impact loads has attracted great attention all over the world. Progressive collapse analysis is essential for an economic and safe design of building structures against progressive collapse to blast and impact loads. Because of the catastrophic nature of progressive collapse and the potentially high cost of constructing or retrofitting buildings to resist it, it is imperative that the progressive collapse analysis methods be reliable. For engineers, their methodology to carry out progressive collapse evaluation need not only be accurate and concise, but also be easily used and works fast. Thus, many researchers have been spending lots of effort in developing reliable, efficient and straightforward progressive collapse analysis methods recently. In the present paper, current progressive collapse analysis methods available in the literature are reviewed. Their suitability, applicability and reliability are discussed. Our recent proposed new method for progressive collapse analysis of reinforced concrete frames under blast loads is also introduced. 展开更多
关键词 progressive collapse analysis building structures blast load impact load
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Risk factors for progressive ischemic stroke: A retrospective analysis 被引量:2
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作者 Ding Qin Junhong Chen Hongyun Jiao Jing Yi Ying Zhang Fengsheng Li 《Neural Regeneration Research》 SCIE CAS CSCD 2007年第11期698-701,共4页
BACKGROUND: Progressive ischemic stroke has higher fatality rate and disability rate than common cerebral infarction, thus it is very significant to investigate the early predicting factors related to the occurrence ... BACKGROUND: Progressive ischemic stroke has higher fatality rate and disability rate than common cerebral infarction, thus it is very significant to investigate the early predicting factors related to the occurrence of progressive ischemic stroke, the potential pathological mechanism and the risk factors of early intervention for preventing the occurrence of progressive ischemic stroke and ameliorating its outcome. OBJECTIVE: To analyze the possible related risk factors in patients with progressive ishcemic stroke, so as to provide reference for the prevention and treatment of progressive ishcemic stroke. DESIGN: A retrospective analysis. SETTING: Department of Neurology, General Hospital of Beijing Coal Mining Group. PARTICIPANTS: Totally 280 patients with progressive ischemic stroke were selected from the Department of Neurology, General Hospital of Beijing Coal Mining Group from March 2002 to June 2006, including 192 males and 88 females, with a mean age of (62±7) years old. They were all accorded with the diagnostic standards for cerebral infarction set by the Fourth National Academic Meeting for Cerebrovascular Disease in 1995, and confired by CT or MRI, admitted within 24 hours after attack, and the neurological defect progressed gradually or aggravated in gradients within 72 hours after attack, and the aggravation of neurological defect was defined as the neurological deficit score decreased by more than 2 points. Meanwhile, 200 inpatients with non-progressive ischemic stroke (135 males and 65 females) were selected as the control group. METHODS: After admission, a univariate analysis of variance was conducted using the factors of blood pressure, history of diabetes mellitus, fever, leukocytosis, levels of blood lipids, fibrinogen, blood glucose and plasma homocysteine, cerebral arterial stenosis, and CT symptoms of early infarction, and the significant factors were involved in the multivariate non-conditional Logistic regression analysis. MAIN OUTCOME MEASURES: Results of the univariate analysis of variance of the factors related to progressive ischemic stroke; Results of the multivariate regression analysis. RESULTS: All the 480 patients were involved in the analysis of results. ① Results of the univariate analysis variance: There were significantly more patients with fever, leukocytosis, history of diabetes mellitus, cerebral arterial stenosis and CT symptoms of early infarction in the progressive ischemic stroke group than in the control group (P 〈 0.01); The levels of blood glucose and fibrinogen in the progressive ischemic stroke group were significantly higher than those in the control group, while the level of blood pressure was significantly lower than that in the control group (P 〈 0.05 - 0.01). ② Results of the multivariate Logistic regression analysis: The independent predicting factors for progressive ischemic stroke were history of diabetes mellitus, fever, leukocytosis, cerebral arterial stenosis, CT symptoms of early infarction, blood glucose and blood pressure (OR =2.61,2.96, 3.79, 1.03, 3.57, 2.68, 95% CI 0.92 - 3.59, P 〈 0.05 - 0.01). CONCLUSION: History of diabetes mellitus, fever, leukocytosis, levels of blood pressure, blood glucose, cerebral arterial stenosis and CT symptoms of early infarction are the risk factors for progress ischemic stroke 展开更多
关键词 progress ischemic stroke risk factors retrospective analysis
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The Research Progress and Prospect Analysis of Germ-Remaining Rice Whitener 被引量:2
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作者 WAN Zhihua XIA Jiqing KANG Defu 《Journal of Northeast Agricultural University(English Edition)》 CAS 2008年第2期84-87,共4页
In this paper, the backdrop and significance of the research of germ-remaining rice whitener firstly were expatiated. Then, the study progress in China and overseas was summarized. Lastly, the research prospect of thi... In this paper, the backdrop and significance of the research of germ-remaining rice whitener firstly were expatiated. Then, the study progress in China and overseas was summarized. Lastly, the research prospect of this kind of whitener in China was analyzed. It is hoped that it can coach the design of germ-remaining rice whitener. 展开更多
关键词 germ-remaining rice whitening technics research progress prospect analysis
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Knowledge Map of Soil Nutrient Migration Analysis Based on WOS (Web of Science) Database
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作者 Jiafeng Wang Jingsheng Chen +2 位作者 Qiuliang Cai Jinsheng Huang Liuqiang Zhou 《Agricultural Sciences》 CAS 2023年第3期398-421,共24页
It is important to understand the research trends and hotspots of global soil nutrient migration and control. Based on the core collection of WOS (Web of Science), citespace knowledge map analysis tool was used to ana... It is important to understand the research trends and hotspots of global soil nutrient migration and control. Based on the core collection of WOS (Web of Science), citespace knowledge map analysis tool was used to analyze the number of publications, cooperation networks, disciplines, research hotspots and frontier trends on nutrient migration in soil. The results showed that: the number of publications on the study of soil nutrient migration showed a good growth from 1990 to 2021. 173 countries had cooperative relationships. The number of articles published in the United States and China was significantly higher than that in other countries, while Chinese Academy of Sciences was the institution with the largest number of publications. It was a comprehensive system that permeates with agriculture, environmental science, botany and other disciplines. The research of nutrient migration in soil mainly focused on the measures of microbial community in different land types to promote nutrient transformation, improve soil fertility and reduce nutrient loss. In the future, the research trends will be the management measures of soil nutrient loss, the relationship between the change of soil nutrient and plant community diversity, and the remediation of agricultural contaminated soil. Through the above analysis, there was an overall understanding of soil nutrient migration. The research on nutrient migration may continue to increase in the future. It is suggested that Chinese research institutions, teams and universities need to strengthen international cooperation, and speed up their integration with the international community. 展开更多
关键词 CiteSpace Soil Nutrients Visual analysis Research progress Nutrient Migration
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A Recursive Method of Time-Frequency Analysis for the Signal Processing of Flutter Test with Progression Variable Speed 被引量:1
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作者 宋叔飚 裴承鸣 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2005年第3期213-217,共5页
Focused on the non-statlonarity and real-time analysis of signal in flutter test with progression variable speed (FTPVS), a new method of recursive time-frequency analysis is presented. The time-varying system is tr... Focused on the non-statlonarity and real-time analysis of signal in flutter test with progression variable speed (FTPVS), a new method of recursive time-frequency analysis is presented. The time-varying system is tracked on-line by building a time-varying parameter model, and then the relevant parameter spectrum can be obtained. The feasibility and advantages of the method are examined by digital simulation. The results of FTPVS at low-speed wind-tunnel promise the engineering application perspective of the method. 展开更多
关键词 flutter test with progression variable speed (FTPVS) non-stationary signal processing recursive time-frequency analysis (RTFA)
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Progressive failure analysis of composite structure based on micro- and macro-mechanics models 被引量:1
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作者 孙志刚 阮绍明 +1 位作者 陈磊 宋迎东 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第8期2980-2988,共9页
Based on parameter design language, a program of progressive failure analysis in composite structures is proposed. In this program, the relationship between macro- and micro-mechanics is established and the macro stre... Based on parameter design language, a program of progressive failure analysis in composite structures is proposed. In this program, the relationship between macro- and micro-mechanics is established and the macro stress distribution of the composite structure is calculated by commercial finite element software. According to the macro-stress, the damaged point is found and the micro-stress distribution of representative volume element is calculated by finite-volume direct averaging micromechanics(FVDAM). Compared with the results calculated by failure criterion based on macro-stress field(the maximum stress criteria and Hashin criteria) and micro-stress field(Huang model), it is proven that the failure analysis based on macro- and micro-mechanics model is feasible and efficient. 展开更多
关键词 composite progressive analysis finite-volume direct averaging micromechanics (FVDAM) failure criteria
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The risks, degree of malignancy and clinical progression of prostate cancer associated with the MDM2 T309G polymorphism: a meta-analysis 被引量:4
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作者 Jie Yang Wen Gao +5 位作者 Ning-Hong Song Wei Wang Jie-Xiu Zhang Pei Lu Li-Xin Hua Min Gu 《Asian Journal of Andrology》 SCIE CAS CSCD 2012年第5期726-731,共6页
To determine the risk, malignant degree and clinical progression of prostate cancer (PCa) associated with mouse double-minute 2 protein (MDM2) T309G variants, a meta-analysis was performed on all eligible publishe... To determine the risk, malignant degree and clinical progression of prostate cancer (PCa) associated with mouse double-minute 2 protein (MDM2) T309G variants, a meta-analysis was performed on all eligible published studies. Odds ratios (ORs) with 95% confidence intervals (CIs) were estimated to assess these associations in seven studies that included 5151 cases and 1003 controls. In the overall analysis, the 309G allele was significantly associated with a decreased PCa risk (0R=0.85, 95% CI: 0.74-0.97); this was also the case for the homozygous comparison (0R--0.72, 95% Ch 0.55-0.95) and the dominant genetic model (0R=0.79, 95% Ch 0.65-0.96). The 309G allele was also found to be significantly associated with lower degrees of PCa malignancy (0R=0.85, 95% Ch 0.75-0.96) in the overall analysis, as well as in the heterozygous comparison (0R=0.79, 95% Ch 0.65-0.96), homozygous comparison (0R=0.76, 95% Ch 0.58-0.98) and dominant genetic model (0R=0.81, 95% CI: 0.68-0.96). Furthermore, grouping analysis showed that the 309G allele in Caucasians was significantly correlated with a decreased PCa risk (0R=0.77, 95% Ch 0.61-0.96); this was also the case in the homozygous comparison (0R=0.51, 95% Ch 0.31-0.86). The grouping analysis also showed that the 309G variant in Caucasians was significantly associated with a lower degree of PCa malignancy in all of the genetic models. In addition, we found that the 309G variant in Caucasians was significantly associated with a slower PCa clinical progression in all of the genetic models. In summary, our meta-analysis showed that the MDM2 309G variant was significantly associated with a decreased PCa risk, lower malignant degree and slower clinical progression in Caucasians, but there was no obvious association in the Asian population. 展开更多
关键词 clinical progression malignant degree MDM2 META-analysis POLYMORPHISM prostate cancer risk
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Progress and Statistical Analysis of Journals on Electrical Engineering in China 被引量:1
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作者 QIN Jie LIN Liang-zhen QI Zhi-ping MA Yu-huan SHEN Guo-liao JING Bo-hong 《电工电能新技术》 CSCD 北大核心 2009年第3期77-80,共4页
The paper has introduced the journals on electrical engineering in China in detail, presented its publication year, the distributions for all elec. eng. journals and its core journals, the position and level of the jo... The paper has introduced the journals on electrical engineering in China in detail, presented its publication year, the distributions for all elec. eng. journals and its core journals, the position and level of the journals, its main journal evaluation indexes, its core journal proportion and inclusion info. by famous international database. The paper offers much information about the journals on electrical engineering in China to readers, and also points out present problems and gives suggestion. 展开更多
关键词 《电工电能新技术》 期刊 编辑工作 发行工作
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Progressive Collapse Analysis of an FPSO Vessel Hull Girder Under Vertical Bending Considering Different Corrosion Models
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作者 Zorareh Nouri Mohammad Reza Khedmati 《Journal of Marine Science and Application》 CSCD 2020年第4期674-692,共19页
Nowadays,with the increasing operational life of ships,the aging effects on their structural behavior need to be investigated precisely.With the corrosive marine environment taken into consideration,one of the importa... Nowadays,with the increasing operational life of ships,the aging effects on their structural behavior need to be investigated precisely.With the corrosive marine environment taken into consideration,one of the important effects of aging that must be studied is thickness degradation.In this paper,with the use of previously proposed equivalent thickness formulations for corroded plates,the progressive collapse analysis software HULLST is enhanced,and then,the effects of different corrosion models of uniform,random,pitting,and tanker pattern types on the ultimate and residual strengths of a floating production,storage,and offloading vessel hull girder are evaluated for the ages of 0 to 25 years.Results reveal that the uniform corrosion and random corrosion models have close outcomes.The value of relative reduction in the ultimate strength of ship hull girder(compared with the intact condition)ranges roughly from 6%for the age of 5 years to 17%for the age of 25 years in the hogging mode.The relative reduction in the ultimate strength ranges from 4%to 16%in the sagging mode.Pitting corrosion and tanker pattern(random)corrosion models lead to higher relative reductions in ultimate strength.The pitting corrosion model leads to a 16%–32%relative reduction in the ultimate strength for the ages of 5–25 years of the ship in either hogging or sagging.The tanker pattern(random)corrosion model leads to a 6%–37%relative reduction in the ultimate strength in the hogging mode and 3%–31%in the sagging mode at ship ages of 5 to 25 years. 展开更多
关键词 Uniform corrosion Random corrosion Pitting corrosion Tanker pattern corrosion progressive collapse analysis Vertical bending Ultimate strength Residual strength
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Influence of Assembly Parameters on Tensile Behavior of Hybrid CMC and Superalloy Bolted Joints by Progressive Damage Analysis
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作者 Chao Lv Feng Li +3 位作者 Shuyuan Zhao Qian Sun Mingrui Li Xinyang Sun 《Journal of Harbin Institute of Technology(New Series)》 CAS 2021年第3期53-60,共8页
With the considerable applications of ceramic matrix composites(CMC) in aircraft engineering, the design of CMC bolted joint gains paramount attention because of its capacity to to improve load-bearing efficiency of a... With the considerable applications of ceramic matrix composites(CMC) in aircraft engineering, the design of CMC bolted joint gains paramount attention because of its capacity to to improve load-bearing efficiency of aircraft key structure. In this work, a 3 D finite element model was established to predict tensile performance and failure modes of single-lap, single-bolt 2 D C/SiC composite, and superalloy joint, which considers the progressive damage behavior of 2 D woven C/SiC composites. On the basis of the developed progressive damage model, a parametric study was carried out to illustrate the effects of bolt preload and bolt-hole clearance on mechanical behaviors of the hybrid bolted joint. It was found that the increase in the value of bolt preload made the failure load grow first and then drop, and the optimum value of bolt preload 5.00 kN generated 56.47% rise in the initial failure load and 22.83% rise in the final failure load for the bolted joint in comparison with zero preload case. As the clearance increased from 0 to 2.00%, the initial and final failure loads respectively declined by 45.88% and 24.02% for 2.00% bolt-hole clearance relative to the neat-fit case. The loss in failure loads can be reduced to compressive stress concentration around the fastening hole-edge area, leading to the appearance of earlier damages by the introduction of increasing bolt hole clearance. 展开更多
关键词 ceramic matrix composite progressive damage analysis tensile performance bolt preload bolt-hole clearance
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Progressive Analysis of Bearing Failure in Pin-Loaded Composite Laminates Using an Elasto-Plastic Damage Model
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作者 Kang Xue 《Materials Sciences and Applications》 2018年第7期576-595,共20页
Bearing failure of composite laminate is very complicated due to the complexity of different failure mechanisms and their interactions. In this paper, an elasto-plastic damage model is built up to describe the process... Bearing failure of composite laminate is very complicated due to the complexity of different failure mechanisms and their interactions. In this paper, an elasto-plastic damage model is built up to describe the process of failure in composite laminates subjected to bearing load. Non-linear behavior of composite before failure is taken into consideration by using a modified Sun-Chen one parameter plasticity model. LaRC05 failure criteria are employed to predict the initiation of failure and the evolution of failure is described by a CDM based stiffness degradation model. Both theory and some application issues like parameter determination are discussed according to phenomenon of experiments. The model is firstly validated by several experiment results of unidirectional laminate and then applicated into the progressive analysis of bearing failure in pin-loaded multidirectional laminates, both intralaminar and interlaminar damage are taken into consideration. The result of finite element analysis is compared with experiment results;it shows good agreements in both mechanical response and progress of failure, so the model can be evaluated to be effective and practical in bearing failure analysis of composite laminates. 展开更多
关键词 ELASTO-PLASTIC Damage Composite LAMINATES BEARING FAILURE progressIVE analysis
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Progressive Failure Analysis of Quasi-isotropic Self-reinforced Polyethylene Composites by Comparing Unsupervised and Supervised Classifications of Acoustic Emission Data
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作者 杨璧玲 黄龙全 梁海先 《Journal of Donghua University(English Edition)》 EI CAS 2014年第4期468-473,共6页
Unsupervised and supervised pattern recognition( PR)techniques are used to classify the acoustic emission( AE) data originating from the quasi-isotropic self-reinforced polyethylene composites,in order to identify the... Unsupervised and supervised pattern recognition( PR)techniques are used to classify the acoustic emission( AE) data originating from the quasi-isotropic self-reinforced polyethylene composites,in order to identify the various mechanisms in the multiangle-ply thermoplastic composites. Ultra-high molecular weight polyethylene / low density polyethylene( UHMWPE / LDPE)composites were made and tested under quasi-static tensile load. The failure process was monitored by the AE technique. The collected AE signals were classified by unsupervised and supervised PR techniques, respectively. AE signals were clustered with unsupervised PR scheme automatically and mathematically. While in the supervised PR scheme,the labeled AE data from simple lay-up UHMWPE / LDPE laminates were utilized as the reference data.Comparison was drawn according to the analytical results. Fracture surfaces of the UHMWPE / LDPE specimens were observed by a scanning electron microscope( SEM) for some physical support. By combining both classification results with the observation results,correlations were established between the AE signal classes and their originating damage modes. The comparison between the two classifying schemes showed a good agreement in the main damage modes and their failure process. It indicates both PR techniques are powerful for the complicated thermoplastic composites. Supervised PR scheme can lead to a more precise classification in that a suitable reference data set is input. 展开更多
关键词 ultra-high molecular weight polyethylene / low density polyethylene(UHMWPE / LDPE) composites THERMOPLASTIC progressive failure analysis damage modes pattern recognition(PR) acoustic emission(AE)
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Research Progress and Review of Green Infrastructure:Visual Analysis of CiteSpace Based on WOS Database
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作者 Yun CHU Xiang JI Yukun HE 《Meteorological and Environmental Research》 CAS 2022年第2期43-49,共7页
In recent years,global ecological and environmental problems have gradually become prominent,and green infrastructure(GI),as one of the effective measures to deal with environmental problems,has gradually attracted at... In recent years,global ecological and environmental problems have gradually become prominent,and green infrastructure(GI),as one of the effective measures to deal with environmental problems,has gradually attracted attention from various fields.In this paper,green infrastructure is taken as the research object,and a total of 1950 related documents in the core database of"web of science"from 1995 to 2021 are taken as the basic data source.By using CiteSpace visualization software,the network of scholars,the distribution characteristics of journals,highly cited articles,prominent keywords,research hotspots and future research trends of related documents are analyzed.The analysis results show that the research on green infrastructure at home and abroad continues to increase;the research on green infrastructure mainly focuses on urban planning,ecosystem services,ecological environment and other issues;the research field of green infrastructure has gradually changed from traditional research fields such as urban planning,architectural engineering and ecology to land use management,urban healthy development,urban sustainable development,physical heat radiation and other fields;at present,research on green infrastructure mainly involves urban planning,ecology and other fields;the future research on green infrastructure will involve the field of physical heat radiation.The purpose is to provide valuable scientific basis and theoretical basis for the future green infrastructure construction in China. 展开更多
关键词 Green infrastructure Research progress COMMENTS CITESPACE Visual analysis
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Systematic review and Meta-analysis comparing modified cross-linking and standard cross-linking for progressive keratoconus 被引量:1
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作者 Yang Liu Yi Liu +5 位作者 Ying-Nan Zhang Ai-Peng Li Jing Zhang Qing-Feng Liang Ying Jie Zhi-Qiang Pan 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2017年第9期1419-1429,共11页
AIM:To compare the effectiveness and safety between modified cross-linking(MC)and standard cross-linking(SC)in mild or moderate progressive keratoconus.METHODS:Eligible studies were retrieved from four electroni... AIM:To compare the effectiveness and safety between modified cross-linking(MC)and standard cross-linking(SC)in mild or moderate progressive keratoconus.METHODS:Eligible studies were retrieved from four electronic databases,including CENTRAL,Clinical Trials gov,Pup Med and OVID MEDLINE.We set post-surgical maximum K value(Kmax)as the primary outcome.In addition,uncorrected and corrected distant visual acuity(UDVA and UDVA),spherical equivalent(SE),endothelial cell density(ECD),central cornea thickness(CCT)and depth of demarcation line(DDL)were Meta-analyzed as secondary outcomes.Mean differences for these outcomes were pooled through either a random-effect model or fixed-effect model according to data heterogeneity.RESULTS:Twenty-four comparative studies either on accelerated cross-linking(AC)compared with SC or on transepithelial cross-linking(TC)compared with SC were included and pooled for analysis.The results indicated that MC was significantly inferior to SC at delaying Kmax deterioration[AC vs SC 0.49(95%CI:0.04-0.94,I2=75%,P=0.03);TC vs SC 1.15(95%CI:0.54-1.75,I2=50%,P=0.0002)].SE decreased significantly for SC when compared to AC[0.62(95%CI:0.38-0.86,I2=22%,P〈0.00001)].DDL of SC was more significantly deeper than that of TC[-133.49(95%CI:-145.94 to-121.04,I2=33%,P〈0.00001)].Other outcomes demonstrated comparable results between MC and SC.CONCLUSION:SC is more favorable at halting the progression of keratoconus,but visual acuity improvement showed comparable results between MCs and SC. 展开更多
关键词 progressive keratoconus cross-linking standardcross-linking accelerated cross-linking trans-epithelial cross-linking META-analysis
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Nonlinear Analysis of Progressive Collapse of Reinforced Concrete(RC)Building by Different Kinds of Column Removal
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作者 Wenchen Ma Lei Jia 《Frontiers Research of Architecture and Engineering》 2020年第1期1-6,共6页
Building collapse mostly can be caused by the loss of loading capacity in a primary structural component,resulting in the failure of surrounding elements,which in turn cause a failure propagation.Progressive collapses... Building collapse mostly can be caused by the loss of loading capacity in a primary structural component,resulting in the failure of surrounding elements,which in turn cause a failure propagation.Progressive collapses may be accidental,due to design deficiencies or errors,material failure or natural phenomenon(e.g.earthquakes)but it can be prevented by upgrade the concrete components’material[1,2].Well-engineered RC buildings generally have a good performance under normal loading conditions.However,faulty design,construction errors,material deterioration,and overloading are always occurred.When part of structure fails,the total load in the whole system will not disappear,which means the load will be redistributed unevenly to the adjacent part of structure.This phenomenon revealed that sustained high stresses in RC elements can lead to catastrophic collapse.Due to very few of papers did the research on the RC elements under high stress level sustained load,relevant experiments should be performed in this area.This paper gives the suggestions about how to apply the load in an experiment if researchers want to know the behavior of elements near to collapse especially focus on RC columns. 展开更多
关键词 progressIVE COLLAPSE of RC structure Nonlinear analysis of RC BUILDING RC behavior under high stress level
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