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Deep learning model based on PET/CT and combination with Cox proportional hazard model for predicting progression of lung invasive adenocarcinoma after surgery 被引量:1
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作者 LI Yingci WU Dongbo GONG Feifei 《中国医学影像技术》 CSCD 北大核心 2024年第8期1194-1198,共5页
Objective To observe the efficacy of deep learning(DL)model based on PET/CT and its combination with Cox proportional hazard model for predicting progressive disease(PD)of lung invasive adenocarcinoma within 5 years a... Objective To observe the efficacy of deep learning(DL)model based on PET/CT and its combination with Cox proportional hazard model for predicting progressive disease(PD)of lung invasive adenocarcinoma within 5 years after surgery.Methods The clinical,PET/CT and 5-year follow-up data of 250 patients with lung invasive adenocarcinoma were retrospectively analyzed.According to PD or not,the patients were divided into the PD group(n=71)and non-PD group(n=179).The basic data and PET/CT findings were compared between groups,among which the quantitative variables being significant different between groups were transformed to categorical variables using receiver operating characteristic(ROC)curve and corresponding cut-off value.Multivariant Cox proportional hazard model was used to select independent predicting factors of PD of lung invasive adenocarcinoma within 5 years after surgery.The patients were divided into training,validation and test sets at the ratio of 6∶2∶2,and PET/CT data in training set and validation set were used to train model and tuning parameters to build the PET/CT DL model,and the combination model was built in serial connection of DL model and the predictive factors.In test set,the efficacy of each model for predicting PD of lung invasive adenocarcinoma within 5 years after surgery was assessed and compared using the area under the curve(AUC).Results Patients'gender and smoking status,as well as the long diameter,SUV max and SUV mean of lesions measured on PET images,the long diameter,short diameter and type of lesions showed on CT were statistically different between groups(all P<0.05).Smoking(HR=1.787[1.053,3.031],P=0.031)and lesion SUV max>4.15(HR=5.249[1.062,25.945],P=0.042)were both predictors of PD of lung invasive adenocarcinoma within 5 years after surgery.In test set,the AUC of PET/CT DL model for predicting PD was 0.847,of the combination model was 0.890,of the latter was higher than of the former(P=0.036).Conclusion DL model based on PET/CT had high efficacy for predicting PD of lung invasive adenocarcinoma within 5 years after surgery.Combining with Cox proportional hazard model could further improve its predicting efficacy. 展开更多
关键词 adenocarcinoma of lung positron-emission tomography and computed tomography deep learning disease progression
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A progressive framework for rotary motion deblurring
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作者 Jinhui Qin Yong Ma +2 位作者 Jun Huang Fan Fan You Du 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期159-172,共14页
The rotary motion deblurring is an inevitable procedure when the imaging seeker is mounted in the rotating missiles.Traditional rotary motion deblurring methods suffer from ringing artifacts and noise,especially for l... The rotary motion deblurring is an inevitable procedure when the imaging seeker is mounted in the rotating missiles.Traditional rotary motion deblurring methods suffer from ringing artifacts and noise,especially for large blur extents.To solve the above problems,we propose a progressive rotary motion deblurring framework consisting of a coarse deblurring stage and a refinement stage.In the first stage,we design an adaptive blur extents factor(BE factor)to balance noise suppression and details reconstruction.And a novel deconvolution model is proposed based on BE factor.In the second stage,a triplescale deformable module CNN(TDM-CNN)is designed to reduce the ringing artifacts,which can exploit the 2D information of an image and adaptively adjust spatial sampling locations.To establish a standard evaluation benchmark,a real-world rotary motion blur dataset is proposed and released,which includes rotary blurred images and corresponding ground truth images with different blur angles.Experimental results demonstrate that the proposed method outperforms the state-of-the-art models on synthetic and real-world rotary motion blur datasets.The code and dataset are available at https://github.com/JinhuiQin/RotaryDeblurring. 展开更多
关键词 Rotary motion deblurring progressive framework Blur extents factor TDM-CNN
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无线传感器网络的ProgressiveSkyline连续查询
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作者 王镝 吴青泉 陈白尘 《计算机科学与探索》 CSCD 2011年第8期760-768,共9页
随着传感器技术的进步,无线传感器网络支持复杂查询在现实应用中越来越重要。Skyline查询由于可用于多种标准下的决策而受到广泛关注。对无线传感器网络中Skyline连续查询进行了研究,提出了一种增量(progressive)算法来解决静态数据集中... 随着传感器技术的进步,无线传感器网络支持复杂查询在现实应用中越来越重要。Skyline查询由于可用于多种标准下的决策而受到广泛关注。对无线传感器网络中Skyline连续查询进行了研究,提出了一种增量(progressive)算法来解决静态数据集中的Skyline查询求解问题,这种增量算法能够递增返回Skyline结果,而无需事先扫描整个数据集。设计了一种新颖的算法来解决流数据集中的Skyline查询维护问题。通过实验对算法性能进行了验证,结果表明,该算法能够大大延长网络的生命周期。 展开更多
关键词 无线传感器网络 SKYLINE查询 progressive算法
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Statistical analysis of generalized exponential distribution under progressive censoring with binomial removals 被引量:11
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作者 Weian Yan Yimin Shi +1 位作者 Baowei Song Zhaoyong Mao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第4期707-714,共8页
The estimation of generalized exponential distribution based on progressive censoring with binomial removals is presented, where the number of units removed at each failure time follows a binomial distribution. Maximu... The estimation of generalized exponential distribution based on progressive censoring with binomial removals is presented, where the number of units removed at each failure time follows a binomial distribution. Maximum likelihood estimators of the parameters and their confidence intervals are derived. The expected time required to complete the life test under this censoring scheme is investigated. Finally, the numerical examples are given to illustrate some theoretical results by means of Monte-Carlo simulation. 展开更多
关键词 binomial removal progressive censoring maximumlikelihood estimator expected experiment time generalized exponential distribution.
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One-step green method to prepare progressive burning gun propellant through gradient denitration strategy 被引量:10
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作者 Shi-ying Li Yu Li +2 位作者 Ya-jun Ding Hao Liang Zhong-liang Xiao 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第4期135-143,共9页
Gradiently denitrated gun propellant(GDGP)prepared by a“gradient denitration”strategy is obviously superior in progressive burning performance to the traditional deterred gun propellant.Currently,the preparation of ... Gradiently denitrated gun propellant(GDGP)prepared by a“gradient denitration”strategy is obviously superior in progressive burning performance to the traditional deterred gun propellant.Currently,the preparation of GDGP employed a tedious two-step method involving organic solvents,which hinders the large-scale preparation of GDGP.In this paper,GDGP was successfully prepared via a novelty and environmentally friendly one-step method.The obtained samples were characterized by FT-IR,Raman,SEM and XPS.The results showed that the content of nitrate groups gradiently increased from the surface to the core in the surface layer of GDGP and the surface layer of GDGP exhibited a higher compaction than that of raw gun propellant,with a well-preserved nitrocellulose structure.The denitration process enabled the propellant surface with regressive energy density and good progressive burning performance,as confirmed by oxygen bomb and closed bomb test.At the same time,the effects of different solvents on the component loss of propellant were compared.The result showed that water caused the least component loss.Finally,the stability of GDGP was confirmed by methyl-violet test.This work not only provided environmentally friendly,simple and economic preparation of GDGP,but also confirmed the stability of GDGP prepared by this method. 展开更多
关键词 Gradiently denitrated gun propellant One-step green method DENITRATION progressive burning Stability
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Inference for dependence competing risks from bivariate exponential model under generalized progressive hybrid censoring with partially observed failure causes 被引量:2
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作者 WANG Liang LI Huanyu MA Jin'ge 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第1期201-208,共8页
Inference are considered for the dependence competing risks model by using the Marshal-Olkin bivariate exponential distribution. Under generalized progressively hybrid censoring with partially observed failure causes,... Inference are considered for the dependence competing risks model by using the Marshal-Olkin bivariate exponential distribution. Under generalized progressively hybrid censoring with partially observed failure causes, the maximum likelihood estimators are established, and the approximate confidence intervals are also constructed via the observed Fisher information matrix.Moreover, Bayes estimates and highest probability density credible intervals are presented and the importance sampling technique is used to compute corresponding results. Finally, the numerical analysis is proposed for illustration. 展开更多
关键词 DEPENDENCE competing risk generalized progressIVE HYBRID CENSORING BIVARIATE exponential distribution Bayesian inference.
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Analysis of progressive failure of pillar and instabilitycriterion based on gradient-dependent plasticity 被引量:8
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作者 王学滨 《Journal of Central South University of Technology》 2004年第4期445-450,共6页
A mechanical model for strain softening pillar is proposed considering the characteristics of progressive shear failure and strain localization. The pillar undergoes elastic, strain softening and slabbing stages. In t... A mechanical model for strain softening pillar is proposed considering the characteristics of progressive shear failure and strain localization. The pillar undergoes elastic, strain softening and slabbing stages. In the elastic stage, vertical compressive stress and deformation at upper end of pillar are uniform, while in the strain softening stage there appears nonuniform due to occurrence of shear bands, leading to the decrease of load-carrying capacity. In addition, the size of failure zone increases in the strain softening stage and reaches its maximum value when slabbing begins. In the latter two stages, the size of elastic core always decreases. In the slabbing stage, the size of failure zone remains a constant and the pillar becomes thinner. Total deformation of the pillar is derived by linearly elastic Hookes law and gradient-dependent plasticity where thickness of localization band is determined according to the characteristic length. Post-peak stiffness is proposed according to analytical solution of averaged compressive stress-average deformation curve. Instability criterion of the pillar and roof strata system is proposed analytically (using) instability condition given by Salamon. It is found that the constitutive parameters of material of pillar, the geometrical size of pillar and the number of shear bands influence the stability of the system; stress gradient controls the starting time of slabbing, however it has no influence on the post-peak stiffness of the pillar. 展开更多
关键词 instability criterion strain softening pillar strain localization shear band progressive failure (slabbing ) rock burst
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Progressive failure processes of reinforced slopes based on general particle dynamic method 被引量:4
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作者 赵毅 周小平 钱七虎 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第10期4049-4055,共7页
In order to resolve grid distortions in finite element method(FEM), the meshless numerical method which is called general particle dynamics(GPD) was presented to simulate the large deformation and failure of geomateri... In order to resolve grid distortions in finite element method(FEM), the meshless numerical method which is called general particle dynamics(GPD) was presented to simulate the large deformation and failure of geomaterials. The Mohr-Coulomb strength criterion was implemented into the code to describe the elasto-brittle behaviours of geomaterials while the solid-structure(reinforcing pile) interaction was simulated as an elasto-brittle material. The Weibull statistical approach was applied to describing the heterogeneity of geomaterials. As an application of general particle dynamics to slopes, the interaction between the slopes and the reinforcing pile was modelled. The contact between the geomaterials and the reinforcing pile was modelled by using the coupling condition associated with a Lennard-Jones repulsive force. The safety factor, corresponding to the minimum shear strength reduction factor "R", was obtained, and the slip surface of the slope was determined. The numerical results are in good agreement with those obtained from limit equilibrium method and finite element method. It indicates that the proposed geomaterial-structure interaction algorithm works well in the GPD framework. 展开更多
关键词 general particle dynamic algorithm(GPD) slope stability progressive failure process geomaterial-structure interaction
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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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Research Progress on Northern Leaf Blight in Corn 被引量:2
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作者 ZHAO Yingnan WANG Zhenhua 《Journal of Northeast Agricultural University(English Edition)》 CAS 2009年第2期66-71,共6页
The northem corn leaf blight is one of the most serious diseases in maize production. The research progress on etiology, generation law and control strategy, antigen identification, resistance mechanism and inheritanc... The northem corn leaf blight is one of the most serious diseases in maize production. The research progress on etiology, generation law and control strategy, antigen identification, resistance mechanism and inheritance of this disease was discussed. And the research work which should be enhanced in China was pointed out, such as mechanism of resistance inheritance, developing function marker, gene mining, screening resistance resource and dominant physiological race in different areas. 展开更多
关键词 CORN northern leaf blight progress
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A statistical inference for generalized Rayleigh model under Type-Ⅱ progressive censoring with binomial removals 被引量:2
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作者 REN Junru GUI Wenhao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第1期206-223,共18页
This paper considers the parameters and reliability characteristics estimation problem of the generalized Rayleigh distribution under progressively Type-Ⅱ censoring with random removals,that is,the number of units re... This paper considers the parameters and reliability characteristics estimation problem of the generalized Rayleigh distribution under progressively Type-Ⅱ censoring with random removals,that is,the number of units removed at each failure time follows the binomial distribution.The maximum likelihood estimation and the Bayesian estimation are derived.In the meanwhile,through a great quantity of Monte Carlo simulation experiments we have studied different hyperparameters as well as symmetric and asymmetric loss functions in the Bayesian estimation procedure.A real industrial case is presented to justify and illustrate the proposed methods.We also investigate the expected experimentation time and discuss the influence of the parameters on the termination point to complete the censoring test. 展开更多
关键词 Type-Ⅱprogressive censoring with random removals generalized Rayleigh distribution reliability characteristic maximum likelihood estimation Markov chain Monte Carlo method expected experimentation time
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PROGRESS OF SMCE CHEMISTRY RESEARCH IN CHINA DURING 1995─1997 被引量:1
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作者 WANG Shi-jie OUYANG Zi-yuan (State Key Laboratorp of Environmental Geochemistry,Institute of Geochemistry, The Chinese Academy of Sciences, Guiyang 550002) 《空间科学学报》 CAS CSCD 北大核心 1998年第S1期21-26,共6页
Over the past years Chinese space chemists have done much work on space chemistry and related disciplines, especially on the solar nebular evolution,meteorjtes, comparative planetology and the origin and evolution of ... Over the past years Chinese space chemists have done much work on space chemistry and related disciplines, especially on the solar nebular evolution,meteorjtes, comparative planetology and the origin and evolution of the Earth.In this paper, the authors outline the main achievements and briefly describe some new views and hypotheses. 展开更多
关键词 progress SPACE CHEMISTRY
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Research Progress in Microbiological Degradation of Bensulfuron-Methyl Herbicide 被引量:1
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作者 XIONG Minghua LI Chunyan 《Journal of Northeast Agricultural University(English Edition)》 CAS 2009年第1期81-85,共5页
This paper reviewed the strategies and methods of screening for microorganisms having strong ability bensulfuron-methyl (BSM), and discussed BSM degradation pathways and factors affecting its microbial metabolism pr... This paper reviewed the strategies and methods of screening for microorganisms having strong ability bensulfuron-methyl (BSM), and discussed BSM degradation pathways and factors affecting its microbial metabolism prospected the research emphasis in the future to remove Finally, it 展开更多
关键词 BENSULFURON-METHYL microbiological degradation progress
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E-Bayesian estimation for competing risk model under progressively hybrid censoring 被引量:3
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作者 Min Wu Yimin Shi Yan Wang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第4期936-944,共9页
This paper considers the Bayesian and expected Bayesian(E-Bayesian) estimations of the parameter and reliability function for competing risk model from Gompertz distribution under Type-I progressively hybrid censori... This paper considers the Bayesian and expected Bayesian(E-Bayesian) estimations of the parameter and reliability function for competing risk model from Gompertz distribution under Type-I progressively hybrid censoring scheme(PHCS). The estimations are obtained based on Gamma conjugate prior for the parameter under squared error(SE) and Linex loss functions. The simulation results are provided for the comparison purpose and one data set is analyzed. 展开更多
关键词 Bayesian estimation expected Bayesian(E-Bayesian) estimation Gompertz distribution Type-I progressively hybrid censoring
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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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Cotton germplasm improvement and progress in Pakistan 被引量:2
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作者 RAZZAQ Abdul ZAFAR Muhammad Mubashar +5 位作者 ALI Arfan HAFEEZ Abdul BATOOL Wajeeha SHI Yuzhen GONG Wankui YUAN Youlu 《Journal of Cotton Research》 2021年第1期76-89,共14页
Cotton(Gossypium spp.)contributes significantly to the economy of cotton-producing countries.Pakistan is the fourth-largest producer of cotton after China,the USA and India.The average yield of cotton is about 570.99 ... Cotton(Gossypium spp.)contributes significantly to the economy of cotton-producing countries.Pakistan is the fourth-largest producer of cotton after China,the USA and India.The average yield of cotton is about 570.99 kg.hm^(−2) in Pakistan.Climate change and different biotic stresses are causing reduction in cotton production.Transgenic approaches have unique advantage to tackle all these problems.However,how to confer permanent resistance in cotton against insects through genetic modification,is still a big challenge to address.Development of transgenic cotton has been proven to be effective.But its effectiveness depends upon several factors,including heterogeneity,seed purity,diffusion of varieties,backcrossing and ethical concerns.Cotton biotechnology was initiated in Pakistan in 1992–1993 with a focus on acquiring cotton leaf curl virus(CLCuV)-resistant insect-resistant,and improving fiber quality.This review summarizes the use of molecular markers,QTLs,GWAS,and gene cloning for cotton germplasm improvement,particularly in Pakistan. 展开更多
关键词 Genetic progress Bt Cotton GWAS Cotton biology Cotton economy Molecular markers
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NEW PROGRESS IN MINERAL PROCESSING——REPORT ON FIRST INTERNATIONAL CONFERENCE ON MODERN PROCESS MINERALOGY AND MINERAL PROCESSING 被引量:1
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作者 Shi Daxin (Beijing General Research Institute of Mining and Metallurgy, Beijing 100044) 《有色金属》 CSCD 1993年第3期81-84,共4页
The first International Conference on Modern Process Mineralogy and Mineral Processing, organized by the Nonferrous Metals Society of China and hosted by Beijing General Research Institute of Mining and Metallurgy,was... The first International Conference on Modern Process Mineralogy and Mineral Processing, organized by the Nonferrous Metals Society of China and hosted by Beijing General Research Institute of Mining and Metallurgy,was held on September 22-25,1992,in Beijing,China.About 350 scholars and experts from 25 countries and regions showed up at the conference and 130 papers were presented,among them 98 papers are of mineral processing.Some of the papers given in mineral processing are summed up as follows. 展开更多
关键词 NEW progress IN MINERAL PROCESSING REPORT ON FIRST INTERNATIONAL CONFERENCE ON MODERN PROCESS MINERALOGY AND MINERAL PROCESSING
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Progressive collapse resisting capacity of reinforced concrete load bearing wall structures 被引量:1
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作者 Alireza Rahai Alireza Shahin Farzad Hatami 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第7期2730-2738,共9页
Reinforced concrete(RC) load bearing wall is widely used in high-rise and mid-rise buildings. Due to the number of walls in plan and reduction in lateral force portion, this system is not only stronger against earthqu... Reinforced concrete(RC) load bearing wall is widely used in high-rise and mid-rise buildings. Due to the number of walls in plan and reduction in lateral force portion, this system is not only stronger against earthquakes, but also more economical. The effect of progressive collapse caused by removal of load bearing elements, in various positions in plan and stories of the RC load bearing wall system was evaluated by nonlinear dynamic and static analyses. For this purpose, three-dimensional model of 10-story structure was selected. The analysis results indicated stability, strength and stiffness of the RC load-bearing wall system against progressive collapse. It was observed that the most critical condition for removal of load bearing walls was the instantaneous removal of the surrounding walls located at the corners of the building where the sections of the load bearing elements were changed. In this case, the maximum vertical displacement was limited to 6.3 mm and the structure failed after applying the load of 10 times the axial load bored by removed elements. Comparison between the results of the nonlinear dynamic and static analyses demonstrated that the "load factor" parameter was a reasonable criterion to evaluate the progressive collapse potential of the structure. 展开更多
关键词 reinforced concrete(RC) load bearing wall structure progressive collapse fiber sections nonlinear analysis load factor method
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Research Progress and Direction of Huangshan Granite Formation and Evolution
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作者 Wei Li,Jinhua Pan,Jinfang Han,Cheng Wang Management Office of Mt.Huangshan Global Geopark,Huangshan 245800,China. 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期302-302,共1页
Mt.Huangshan is a well-known scenic and historic interest area which is characterized by granite land-forms.Since the approval of membership to the Global Geopark Network,the management committee of Huangshan Scenic A... Mt.Huangshan is a well-known scenic and historic interest area which is characterized by granite land-forms.Since the approval of membership to the Global Geopark Network,the management committee of Huangshan Scenic Area has carried out a series of study and international correlation research of Huangshan granite formation and evolution.Based on the field observation,sampling。 展开更多
关键词 Huangshan GRANITE FORMATION and EVOLUTION progress
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National Report on Space Medicine Progress in 2012–2014
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作者 LI Yinghui ZHANG Xiaoyou +6 位作者 WAN Yumin DING Bai LIU Zhaoxia LING Shukuan BAI Yanqiang CHEN Shanguang LIU Shujuan 《空间科学学报》 CAS CSCD 北大核心 2014年第5期740-746,共7页
The application of manned spaceflight makes a great impetus on the development of space medicine. With the deep growth of Chinese manned space, our national space medicine has attained great achievements. In this pape... The application of manned spaceflight makes a great impetus on the development of space medicine. With the deep growth of Chinese manned space, our national space medicine has attained great achievements. In this paper, the basic research of Space Medicine and its application in China during 2012–2014 were briefly reviewed. 展开更多
关键词 SPACEFLIGHT SPACE MEDICINE progress
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