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Factor Structure and Longitudinal Invariance of the CES-D across Diverse Residential Backgrounds in Chinese Adolescents
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作者 Yanjing Cao Chenchen Xu +2 位作者 Qi Li Shan Lu Jing Xiao 《International Journal of Mental Health Promotion》 2024年第4期261-269,共9页
Background:Valid and reliable measures of depressive symptoms are crucial for understanding risk factors,outcomes,and interventions across rural and urban settings.Despite this need,the longitudinal invariance of thes... Background:Valid and reliable measures of depressive symptoms are crucial for understanding risk factors,outcomes,and interventions across rural and urban settings.Despite this need,the longitudinal invariance of these measures over time remains understudied.This research explores the structural components of the Center for Epidemiological Studies Depression Scale(CES-D)and examines its consistency across various living environments and temporal stability in a cohort of Chinese teenagers.Method:In the initial phase,1,042 adolescents furnished demographic details and undertook the CES-D assessment.After a three-month interval,967 of these participants repeated the CES-D evaluation.The study employed Confirmatory factor analysis(CFA)to scrutinize the scale’s structural integrity.We investigated factorial invariance by conducting a twopronged CFA:one comparing urban vs.rural backgrounds,and another contrasting the results from the initial assessment with those from the follow-up.Results:The CES-D demonstrated adequate reliability in both rural and urban high school student samples.The preliminary four-factor model applied to the CES-D demonstrated a good fit with the collected data.Invariance tests,including multigroup analyses comparing rural and urban samples and longitudinal assessments,confirmed the scale’s invariance.Conclusions:The results suggest that the CES-D serves as a reliable instrument for evaluating depressive symptoms among Chinese adolescents.Its applicability is consistent across different living environments and remains stable over time. 展开更多
关键词 DEPRESSION factor structure measurement invariance Chinese adolescent longitudinal invariance
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Drivers of spatial structure in thinned forests
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作者 Zichun Wang Yaoxiang Li +4 位作者 Guangyu Wang Zheyu Zhang Ya Chen Xiaoli Liu Rundong Peng 《Forest Ecosystems》 SCIE CSCD 2024年第2期202-213,共12页
Background:As is widely known,an increasing number of forest areas were managed to preserve and enhance the health of forest ecosystems.However,previous research on forest management has often overlooked the importanc... Background:As is widely known,an increasing number of forest areas were managed to preserve and enhance the health of forest ecosystems.However,previous research on forest management has often overlooked the importance of structure-based.Aims:Our objectives were to define the direction of structure-based forest management.Subsequently,we investigated the relationships between forest structure and the regeneration,growth,and mortality of trees under different thinning treatments.Ultimately,the drivers of forest structural change were explored.Methods:On the basis of 92 sites selected from northeastern China,with different recovery time (from 1 to 15years) and different thinning intensities (0–59.9%) since the last thinning.Principal component analysis (PCA)identified relationships among factors determining forest spatial structure.The structural equation model (SEM)was used to analyze the driving factors behind the changes in forest spatial structure after thinning.Results:Light thinning (0–20%trees removed) promoted forest regeneration,and heavy thinning (over 35% of trees removed) facilitated forest growth.However,only moderate thinning (20%–35%trees removed) created a reasonable spatial structure.While dead trees were clustered,and they were hardly affected by thinning intensity.Additionally,thinning intensity,recovery time,and altitude indirectly improve the spatial structure of the forest by influencing diameter at breast height (DBH) and canopy area.Conclusion:Creating larger DBH and canopy area through thinning will promote the formation of complex forest structures,which cultivates healthy and stable forests. 展开更多
关键词 THINNING Natural secondary forest Spatial structure Dynamic changes Growth factors structural equation modeling
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Recent developments in the physical structure of solid formulations:a comprehensive review
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作者 Zhe Li Xiaosui Luo +8 位作者 Abid Naeem Qiong Li Yao Zhang Yongmei Guan Lihua Chen Weifeng Zhu Zhengji Jin Yi Feng Liangshan Ming 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2024年第10期877-905,共29页
Solid formulations represent the most widely used dosage forms,and their structural attributes significantly impact the efficacy of drugs.Consequently,delving into the study of solid formulation structures is of param... Solid formulations represent the most widely used dosage forms,and their structural attributes significantly impact the efficacy of drugs.Consequently,delving into the study of solid formulation structures is of paramount importance.This paper employs bibliometrics to summarize references on solid formulations and physical structure over the past 5 years,providing a visual representation through CiteSpace.Additionally,we explore influential factors affecting the structure of solid formulations at three distinct levels:raw material,intermediate,and final product.It delves into the discussion of various characterization techniques employed to analyze the physical structure of solid formulations.The techniques include scanning electron microscopy,transmission electron microscopy,X-ray diffraction,nuclear magnetic resonance,LF-nuclear magnetic resonance,thermal analysis,and terahertz.Emphasis is placed on the significance of investigating formulation structures,serving as a found ational step for future research and development in this field.This comprehensive approach aims to contribute to the understanding and advancement of solid formulations for enhanced drug effectiveness. 展开更多
关键词 Solid formulations Physical structure CITESPACE Affecting factors Physical characterization
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Identification of time-varying system and energy-based optimization of adaptive control in seismically excited structure
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作者 Elham Aghabarari Fereidoun Amini Pedram Ghaderi 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第1期227-240,共14页
The combination of structural health monitoring and vibration control is of great importance to provide components of smart structures.While synthetic algorithms have been proposed,adaptive control that is compatible ... The combination of structural health monitoring and vibration control is of great importance to provide components of smart structures.While synthetic algorithms have been proposed,adaptive control that is compatible with changing conditions still needs to be used,and time-varying systems are required to be simultaneously estimated with the application of adaptive control.In this research,the identification of structural time-varying dynamic characteristics and optimized simple adaptive control are integrated.First,reduced variations of physical parameters are estimated online using the multiple forgetting factor recursive least squares(MFRLS)method.Then,the energy from the structural vibration is simultaneously specified to optimize the control force with the identified parameters to be operational.Optimization is also performed based on the probability density function of the energy under the seismic excitation at any time.Finally,the optimal control force is obtained by the simple adaptive control(SAC)algorithm and energy coefficient.A numerical example and benchmark structure are employed to investigate the efficiency of the proposed approach.The simulation results revealed the effectiveness of the integrated online identification and optimal adaptive control in systems. 展开更多
关键词 integrated online identification time-varying systems structural energy multiple forgetting factor recursive least squares optimal simple adaptive control algorithm
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The Interrelationship between Culture and Capital Structure:Evidence from International Retailers
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作者 Sisi Xu 《Proceedings of Business and Economic Studies》 2024年第2期66-72,共7页
The present study investigates the influence of cultural factors in 2022 on the capital structure of global retailers.There are sixteen retailers from eight countries in the sample.In recent times,numerous academician... The present study investigates the influence of cultural factors in 2022 on the capital structure of global retailers.There are sixteen retailers from eight countries in the sample.In recent times,numerous academicians have taken an interest in examining the capital structure and business model of retailers,owing to their swift and consistent growth.However,the fact that the majority of research originates from the retailers’host country gives rise to debate regarding the applicability of the capital structure of said retailers to countries with distinct cultural environments.Consequently,academics have begun to investigate whether the capital structure of multinational retailers is impacted by the diversity of national cultures. 展开更多
关键词 Cultural factors Capital structure Global retailers Business model National cultures
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Network autoregression model with grouped factor structures
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作者 ZHANG Zhiyuan ZHU Xuening 《中山大学学报(自然科学版)(中英文)》 CAS CSCD 北大核心 2023年第5期24-37,共14页
Network autoregression and factor model are effective methods for modeling network time series data.In this study,we propose a network autoregression model with a factor structure that incorporates a latent group stru... Network autoregression and factor model are effective methods for modeling network time series data.In this study,we propose a network autoregression model with a factor structure that incorporates a latent group structure to address nodal heterogeneity within the network.An iterative algorithm is employed to minimize a least-squares objective function,allowing for simultaneous estimation of both the parameters and the group structure.To determine the unknown number of groups and factors,a PIC criterion is introduced.Additionally,statistical inference of the estimated parameters is presented.To assess the validity of the proposed estimation and inference procedures,we conduct extensive numerical studies.We also demonstrate the utility of our model using a stock dataset obtained from the Chinese A-Share stock market. 展开更多
关键词 network autoregression factor structure HETEROGENEITY latent group structure network time series
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Performance-based global reliability assessment of a high-rise frame-core tube structure subjected to multi-dimensional stochastic earthquakes 被引量:2
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作者 Liu Zhangjun Ruan Xinxin Liu Zixin 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2022年第2期395-415,共21页
When evaluating the seismic safety and reliability of complex engineering structures,it is a critical problem to reasonably consider the randomness and multi-dimensional nature of ground motions.To this end,a proposed... When evaluating the seismic safety and reliability of complex engineering structures,it is a critical problem to reasonably consider the randomness and multi-dimensional nature of ground motions.To this end,a proposed modeling strategy of multi-dimensional stochastic earthquakes is addressed in this study.This improved seismic model has several merits that enable it to better provide seismic analyses of structures.Specifically,at first,the ground motion model is compatible with the design response spectrum.Secondly,the evolutionary power spectrum involved in the model and the design response spectrum are constructed accordingly with sufficient consideration of the correlation between different seismic components.Thirdly,the random function-based dimension-reduction representation is applied,by which seismic modeling is established,with three elementary random variables.Numerical simulations of multi-dimensional stochastic ground motions in a specific design scenario indicate the effectiveness of the proposed modeling strategy.Moreover,the multi-dimensional seismic response and the global reliability of a high-rise frame-core tube structure is discussed in detail to further illustrate the engineering applicability of the proposed method.The analytical investigations demonstrate that the suggested stochastic model of multi-dimensional ground motion is available for accurate seismic response analysis and dynamic reliability assessment of complex engineering structures for performance-based seismic resistance design. 展开更多
关键词 multi-dimensional stochastic ground motion dimension-reduction representation frame-core tube structure global dynamic reliability performance-based seismic design
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Genetic Structure of Reaumuria soongorica Population in Fukang Desert, Xinjiang and Its Relationship with Ecological Factors 被引量:13
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作者 徐莉 王祎玲 +5 位作者 王戌梅 张林静 岳明 顾峰雪 潘晓玲 赵桂仿 《Acta Botanica Sinica》 CSCD 2003年第7期787-794,共8页
Genetic structure and differentiation of Reaumuria soongorica (Pall.) Maxim population from the desert of Fukang, Xinjiang, were assessed by means of random amplified polymorphic DNA (RAPD) markers. High genetic diver... Genetic structure and differentiation of Reaumuria soongorica (Pall.) Maxim population from the desert of Fukang, Xinjiang, were assessed by means of random amplified polymorphic DNA (RAPD) markers. High genetic diversity and differentiation were revealed in the population of R soongorica by 15 random primers. One hundred and thirty-six individuals from seven subpopulations were sampled in the study. Seventy-one loci have been detected, and among them 69 were polymorphic. The mean proportion of polymorphic loci (PPB) was 97.18%. The analyses of Shannon information index (0.307 5), Nei's gene diversity (0.312 7) and G(ST)(0.312 0) indicated that there were more genetic variations within the subpopulations than those among the subpopulations. The results of AMOVA analysis showed that 61.58% of the genetic variations existed within subpopulations, and 38.02% among the subpopulations. The gene flow among the subpopulations of R soongorica (Nm = 1.102 8) was much less than that of the common anemophytes (Nm = 5.24), so genetic differentiation among the subpopulations occurred to some extent. Additionally, through the use of clustering and the correlation analyses, we found that the genetic structure of natural population of R soongorica was related to some ecological factors (soil factors mainly) of the oasis-desert transition zone. The genetic diversity level of R soongorica had negative correlation with the content of total soil P and Cl significantly (P < 0.05). On the contrary, it had significant positive correlation with CO32- (P < 0.05), showing that the distribution of the individuals of R soongorica in the sampled areas correlates with certain soluble salt. Furthermore, the genetic diversity of the natural population of R soongorica increased with the decreasing of the content of soil organic matters, water, total N and total P in soil. The paper concluded that the microenvironment ecological factors played an important role in the adaptive evolution of R soongorica population. 展开更多
关键词 Reaumuria soongorica genetic structure ecological factors desert plant
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Analysis on Fuji Apple Tree Structures and Related Factors under Different Pruning Modes 被引量:1
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作者 郝婕 索相敏 +4 位作者 李学营 魏亮 王献革 鄢新民 冯建忠 《Agricultural Science & Technology》 CAS 2017年第12期2528-2531,2535,共5页
To determine the correlations between the tree structuresof Fuji apple with different pruning modes and each factor, the data about 3 tree structures which were free spindle short shoot, free spindle long shoot and sl... To determine the correlations between the tree structuresof Fuji apple with different pruning modes and each factor, the data about 3 tree structures which were free spindle short shoot, free spindle long shoot and slenderspindle short shoot in Xingtang County of Hebai Province were investigated, then by SPSS anal- ysis, the correlations between the taperingness and each growth factor of inserted small branch were compared. The results showed that the taperingness of central trunk of free spindle dwarf-shoot Fuji apple treeshad negative correlations with each factor of inserted small branch, while the taperingness of central trunk of free spin- dle long-shoot Fuji apple treeshad positive correlations with each factor of inserted small branch, the taperingness of central trunk of slenderspindle short-shootFuji ap- ple treeshad negative correlation with total thickness of inserted small branch, but had positive correlations with other factors. This study can provide a scientifictheo- retical basis for the pruning technology of high-density planting trees grafting by dwarfing self-rooted rootstock. 展开更多
关键词 PRUNING Fuji apple Tree structures Analysis of related factors
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Correlation Between the Animal Community Structure and Environmental Factors in Dongbei Cave and Shuijiang Cave of Guizhou Province 被引量:9
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作者 黎道洪 《Zoological Research》 CAS CSCD 北大核心 2006年第5期481-488,共8页
Mollusks, arthropods and chordates which were visible to the naked eye were observed and collected in Dongbei and Shuijiang caves of Libo county five times between February and July from 2002 to 2005. Four hundred and... Mollusks, arthropods and chordates which were visible to the naked eye were observed and collected in Dongbei and Shuijiang caves of Libo county five times between February and July from 2002 to 2005. Four hundred and forty samples from Dongbei Cave were classified into three phyla, five classes, 10 orders, 20 families and 39 species or groups of species. Four hundred and ninety-eight samples from Shuijiang Cave were classified into three phyla, six classes, 11 orders, 20 families and 25 species or groups of species. Six animal communities were identified in the light belt of the two caves according to their species types and numbers of individuals in the light belt of two cave. The communities which have the highest values of species richness community diversity, maximum diversity, evenness, dominance and community similarity are respectively: B (4. 1059), H (2.4716), B (3.3322), E (0.9042), C (0.3442) and A - C (0. 5251). The community diversity and correlation of environmental factors were also studied. The temperature, humidity, content of CO2 and N2, content of organic matter and some inorganic salts in soil were analyzed by Pearson correlation. The results showed that the content of organic matter in soil is positively related to species number, species richness and maximum community diversity, with correlations of 0. 885, 0.909, 0. 868 respectively (two-tailed significance test, P ≤ 0. 05), and significantly positively related to diversity, with the coefficient of 0.611, (two-tailed significance test, P ≤ 0. 1). This suggests that the content of organic matter in soil is one of the important elements influencing the community variation of cave animals. Outside the cave, temperature and humidity are important factors impacting on community diver- sity. As the temperature in all seasons in the cave is stable and the humidity is always high (above 90% ), the temperature and humidity have weak correlation to community diversity in caves. 展开更多
关键词 Animal community structure Environmental factor Dongbei Cave Shuijiang Cave Guizhou province
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Research on Regional Land Use Structure Change and Influencing Factors——A Case Study of Yining City in Xinjiang
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作者 刘志有 蒲春玲 +1 位作者 董嘉琪 赵晓洁 《Agricultural Science & Technology》 CAS 2012年第12期2655-2657,2662,共4页
This paper analyzes the land use status and land use structure change in 1995-2004 in Yining City, revealing that the agricultural land area has decreased rapidly, and construction land has increased dramatically. Mor... This paper analyzes the land use status and land use structure change in 1995-2004 in Yining City, revealing that the agricultural land area has decreased rapidly, and construction land has increased dramatically. Moreover, this paper inves- tigates the relation of economy, urbanization, location, land system policy with land use structure, and puts forward rationalization proposal for optimization of land use structure, to provide reference for land use measurements in the future. 展开更多
关键词 Land use structure Yining City Influence factors
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Community structure and controlled factor of attached green algae on the Porphyra yezoensis aquaculture rafts in the Subei Shoal, China 被引量:6
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作者 LI Yan XIAO Jie +6 位作者 DING Lanping WANG Zongling SONG Wei FANG Song FAN Shiliang LI Ruixiang ZHANG Xuelei 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第8期93-99,共7页
This study analyzes the community structure, the quantity changes of the algae and the effect of important environmental factors and estimates the total biomass of the attached green algae in the survey areas. The stu... This study analyzes the community structure, the quantity changes of the algae and the effect of important environmental factors and estimates the total biomass of the attached green algae in the survey areas. The study uses data from surveys of the attached green algae on the Porphyra yezoensis aquaculture rafts and data regarding the environmental factors from October 2010 to April 2011 in the Subei Shoal. The attached green algae on the rafts included Ulva prolifera, Capsosiphon groenlandicus, U. linza, U. intestinalis, U. clathrata, and U. cornpressa. The biomass changes of the attached green algae exhibited an inverted parabola: the biomass was the highest (14 898 t) in April, and was the second highest (2 034 t) in November; it was lowest in February (only 729 t) and increased sharply from March to April. The species diversity differed significantly among the seasons. In September and October, when the P. yezoensis aquaculture rafts were initially set up, the attached green algae had a high biodiversity, while from December to the next February, a variety of green algae species coexisted on the rafts, although the biomass was low, and from March to April, as the biomass increased sharply, the species diversity dropped to the minimum. During this time, C. groenlandicus was apparently dominant with the maximum biomass proportion up to 80%, while the U. prolifera proportion increased exponentially to 20% to 40%. The water temperature had a direct regulating effect on the biomass and the species succession of the attached green algae. The estimation of the community dynamics and the biomass of the green algae provided the evidence needed to track the origin of the large-scale green tide in the southern Yellow Sea. 展开更多
关键词 Porphyra yezoensis aquaculture attached green algae community structure controlled factor SubeiShoal
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Influence of environmental factors on corrosion damage of aircraft structure 被引量:4
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作者 Keliang Ren,) Shiwu Gao, Pingping Liu, and Yan Dong Department of Physics & Electrical Information, Ningxia University, Ningxia 750021, China 《Theoretical & Applied Mechanics Letters》 CAS 2011年第6期18-21,共4页
Corrosion is one of the important structural integrity concerns of aging aircraft, and it is estimated that a significant portion of airframe maintenance budgets is directed towards corrosion-related problems for both... Corrosion is one of the important structural integrity concerns of aging aircraft, and it is estimated that a significant portion of airframe maintenance budgets is directed towards corrosion-related problems for both military and commercial aircraft. In order to better understand how environmental factors influence the corrosion damage initiation and propagation on aircraft structure and to predict pre-corrosion test pieces of fatigue life and structural integrity of an effective approach, this paper uses the cellular automaton (CA) method to character the effect of electrolyte concentrations, dissolution probabilities, and temperature on the corrosion damage of a metal structure exposed to an aggressive environment, and the procedure for applying the local rules between the cells of the CA to simulate the corrosion damage evolution is formulated. The simulation results show that the different electrolyte concentrations, dissolution probabilities and temperature, the laws of the dissolution current with time are investigated and they obey the time power function. 展开更多
关键词 aircraft structure corrosion damage environmental factors cellular automaton simula- tions
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Factor input structure,environmental policies,and the export quality upgrade:a perspective of heterogeneity 被引量:3
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作者 Jiayue Liu Jing Xie 《Chinese Journal of Population,Resources and Environment》 2018年第1期67-76,共10页
In the analysis of how environmental regulation affects the comparative advantage of trade,existing literature ignores industry's inherent heterogeneity, which draws remarkably different conclusions. In view of th... In the analysis of how environmental regulation affects the comparative advantage of trade,existing literature ignores industry's inherent heterogeneity, which draws remarkably different conclusions. In view of this, the paper analyzed the mechanism of environmental regulation on the export quality of different industries from the perspective of factor input structure heterogeneity. Based on the panel data of China's manufacturing industry, the paper used the system generalized method of moments method to examine the heterogeneity influence of environmental regulation on manufacturing export quality. The study found that, first, environmental regulation affected the export quality upgrade of the manufacturing sector through offset effect and compensation effect, and the direction of the impact would mainly depend on the industry's factor input structure. Second, for industries with larger fixed-asset investment(FAI) ratio in the factor input structure, the current environmental regulation policy was not conducive to the export quality upgrading of the industries. However, there was a significant U-shaped dynamic relationship between them. As environmental regulations became stricter, when regulatory stringency went beyond the inflection point, the policy would promote the upgrading of export quality. But for industries with smaller proportion of FAI, environmental regulation exerted a favorable impact on the export quality upgrade, following a J-shaped marginal growth curve.Third, for industries with different factor input structure, their export quality had been effectively upgraded as expected by factors like human capital investment, independent R&D, technology introduction, and foreign direct investment; but raising per capita capital stock and expanding enterprise size did not produce significant direct impact on export quality upgrade. These conclusions remained robust after using different measurement methods and replacing with other variables. Therefore, this paper suggests that governments should take industry heterogeneity into consideration and formulate differentiated hierarchical environmental policies.Besides, they should strengthen the enforcement of the current environmental regulation policies. By doing so, enterprises are forced to improve their technology and product quality so that they can better cope with rising compliance costs, eliminate backward industries, and resolve excess capacity. In this way, the economic structure would be transformed and upgraded from the supply side. 展开更多
关键词 Environmental regulation export quality factor input structure industry heterogeneity
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Stability influence factors analysis and construction of a deep beam anchorage structure in roadway roof 被引量:8
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作者 Xie Shengrong Gao Mingming +4 位作者 Chen Dongdong Sun Yanding Pan Hao Su Hai Lan Shizhong 《International Journal of Mining Science and Technology》 EI CSCD 2018年第3期445-451,共7页
Deep beam anchorage structures based on spatial distribution analysis of the cable prestressed field have been proposed for roadway roof support, Stability and other factors that influence deep beam structures are stu... Deep beam anchorage structures based on spatial distribution analysis of the cable prestressed field have been proposed for roadway roof support, Stability and other factors that influence deep beam structures are studied in this paper using mechanical calculations, numerical analysis and field measurements, A mechanical model of deep beam structure subjected to multiple loading is established, including analysis of roof support in the return airway of S1203 working face in the Yuwu coal mine, China, The expression of maximum shear stress in the deep beam structure is deduced according to the stress superposition criterion, It is found that the primary factors affecting deep beam structure stability are deep beam thickness, cable pre-tension and cable spacing, The variation of maximum shear stress distribution and prestressed field diffusion effects according to various factors are analyzed using Matlah and FLAC3DTM software, and practical support parameters of the S1203 return airway roof are determined, According to the observations of rock pressure, there is no evidence of roof separation, and the maximum values of roof subsidence and convergence of wall rock are 72 and 48 mm, respectively, The results show that the proposed roof support design with a deep beam structure is feasible and achieves effective control of the roadway roof, 展开更多
关键词 Support structure Deep beam Maximum shear stress Influencing factors Stability control Roadway roof
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Influencing Factors and Dynamic Mechanism of Industrial Structure from the Perspective of Supply-side Reform 被引量:2
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作者 Deng GAO Shuhui SHAO 《Asian Agricultural Research》 2018年第12期37-40,共4页
The supply-side reform is an important measure for the high-quality development of China's economy in the new era. The purpose of this paper is to explore the mechanism and influence of technological progress,huma... The supply-side reform is an important measure for the high-quality development of China's economy in the new era. The purpose of this paper is to explore the mechanism and influence of technological progress,human capital,consumption demand,resource endowment and government intervention on the adjustment and upgrading of industrial structure,and to deepen the understanding of supply-side reform. 展开更多
关键词 Supply-side REFORM INDUSTRIAL structure Influencing factorS Dynamic mechanism
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Factor Structure of the Center for Epidemiologic Studies Depression Scale in South Korea 被引量:2
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作者 Shuntaro Aoki Akira Tsuda +4 位作者 Satoshi Horiuchi Euiyeon Kim Mayu Naruse Aki Tsuchiyagaito Kwangshik Hong 《Open Journal of Medical Psychology》 2014年第4期301-305,共5页
Results of previous studies from North America reported that only 14 out of the 20 items from the Center for Epidemiologic Studies Depression Scale (CES-D) were required to assess negative affect, somatic symptoms, an... Results of previous studies from North America reported that only 14 out of the 20 items from the Center for Epidemiologic Studies Depression Scale (CES-D) were required to assess negative affect, somatic symptoms, and anhedonia. However, it remains unclear whether this three-factor structure of the CES-D would be valid in South Korea. The purpose of this study is to examine the validity of the three-factor structure with a Korean version of the CES-D. The participants were Korean college students (N = 215), elementary school teachers (N = 234), and parents of elementary school students (N = 230). Confirmatory factor analysis was performed to examine the scale’s validity. Results indicated that the three-factor structure showed acceptable fit to data (comparative fit index = 0.95;root mean square error of approximation = 0.06). The findings indicated that the three-factor structure of the CES-D was valid in South Korea. 展开更多
关键词 DEPRESSIVE SYMPTOMS CES-D factor structure SOUTH Korea
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Influence of Recycled Aggregate Composites on the Factor of Safety of Earthen Structures 被引量:2
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作者 Md. Zakaria Hossain 《International Journal of Geosciences》 2013年第5期844-849,共6页
In this study, six composite reinforcements such as cement composite made of Abandoned Cell Husks (ASH), Stones, Wood chips, Concrete and Bricks have been used along with control specimen. It is known that the materia... In this study, six composite reinforcements such as cement composite made of Abandoned Cell Husks (ASH), Stones, Wood chips, Concrete and Bricks have been used along with control specimen. It is known that the material used in earth reinforcement applications must be safe against tension failure and adhesion failure for its effective utilization in the field and reliable design of earth structures. Single type of material can provide limited reinforcement capability in reinforced earth structures due to its low frictional resistance and poor cohesion. For an optimal response, therefore, composite reinforcement, that fulfils both the requirements such as possess adequate tensile strength and adequate frictional resistance, is getting considerable attention. Slope stability analyses containing six types of reinforcement have been performed. Stability of the slope has been quantified using minimum factor of safety corresponding to critical slip surface. It was observed that the composite reinforcement whose surface treated by brick aggregate enhanced the factor of safety significantly. The paper also depicted the design aids of reinforced slope in terms of embedding lengths and spacing of reinforcements. 展开更多
关键词 Earthen structureS Stability factor COMPOSITE REINFORCEMENT Recycled AGGREGATE
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Preparation and Structure of a New Coagulation Factor XI Catalytic Domain for Drug Discovery 被引量:1
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作者 江龙光 袁彩 +4 位作者 陈宏炜 王宇 赵宝玉 张旭 黄明东 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第7期1021-1029,共9页
Human blood coagulation factor XI (FXI) is a key enzyme in the amplification phase of blood coagulation cascade, and is recognized as an important target for anti-coagulant development in recent years. We designed a... Human blood coagulation factor XI (FXI) is a key enzyme in the amplification phase of blood coagulation cascade, and is recognized as an important target for anti-coagulant development in recent years. We designed a new mutant form of FXIa catalytic domain rhFXI370-607 (N73Q-N113Q-C123S), and report here the facile preparation, protein crystallization, and crystal structure of this protein. We highlight a few unique structural features of FXIa after comparison with the trypsin family serine proteases at sequence and structural levels. This work provides a foundation to develop new small molecular FXIa inhibitors with increased potency and specificity. 展开更多
关键词 human blood coagulation factor XI crystal structure serine proteases INHIBITORS
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Community Structure of the Phytoplankton and Its Relationship with Environmental Factor in Lower Reaches of the Yellow River 被引量:4
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作者 WANG Xiao-chen YANG Xing-zhong +3 位作者 LV Bin-bin XING Juan-juan ZHANG Jian-jun LIU Jing 《Meteorological and Environmental Research》 2012年第7期1-4,共4页
[ Objective] The research aimed to study community structure of the phytoplankton and its relationship with environmental factor in lower reaches of the Yellow River. [ Method] From April to June in 2011, phytoplankto... [ Objective] The research aimed to study community structure of the phytoplankton and its relationship with environmental factor in lower reaches of the Yellow River. [ Method] From April to June in 2011, phytoplankton was conducted qualitative and quantitative researches in Lijin in lower reaches of the Yellow River. By combining population characteristics of the phytoplankton, its'relationship with environmental factor was dis- cussed. [ Result] 114 species and 5 phylum of phytoplankton were observed in the whole river section. The abundance of phytoplankton was 0.90 ×104 -303.35×104 ind/m3, and mean was 27.20 ×104 ind/m3. The biomass of phytoplankton was 0.008-5.890 mg/m3, and mean was 0.641 mg/m3. Shannon-Weaver diversity index, Pielou evenness index and Simpson's diversity index were respectively 1.59, 0.36 and 0.55. SPSS data analysis indicated that transparency was the uppermost environmental factor affected phytoplankton abundance. Phytoplankton abundance had posi- tive correlation with transparency, and the regression equation was y= -393.8 +115.5×-11 .lx2 +0.35x3(n=18, R2 =0.952, F=92.665, P〈0.01 ). [ Conclusion] The community structure of phytoplankton was unstable, and transparency was the uppermost environmental factor affected phyto- plankton abundance in lower reaches of the Yellow River. 展开更多
关键词 PHYTOPLANKTON Community structure Environmental factor Lower reaches of the Yellow River China
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