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Coupled multiphysical model for investigation of influence factors in the application of microbially induced calcite precipitation
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作者 Xuerui Wang Pavan Kumar Bhukya +1 位作者 Dali Naidu Arnepalli Shuang Chen 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期2232-2249,共18页
The study presents a comprehensive coupled thermo-bio-chemo-hydraulic(T-BCH)modeling framework for stabilizing soils using microbially induced calcite precipitation(MICP).The numerical model considers relevant multiph... The study presents a comprehensive coupled thermo-bio-chemo-hydraulic(T-BCH)modeling framework for stabilizing soils using microbially induced calcite precipitation(MICP).The numerical model considers relevant multiphysics involved in MICP,such as bacterial ureolytic activities,biochemical reactions,multiphase and multicomponent transport,and alteration of the porosity and permeability.The model incorporates multiphysical coupling effects through well-established constitutive relations that connect parameters and variables from different physical fields.It was implemented in the open-source finite element code OpenGeoSys(OGS),and a semi-staggered solution strategy was designed to solve the couplings,allowing for flexible model settings.Therefore,the developed model can be easily adapted to simulate MICP applications in different scenarios.The numerical model was employed to analyze the effect of various factors,including temperature,injection strategies,and application scales.Besides,a TBCH modeling study was conducted on the laboratory-scale domain to analyze the effects of temperature on urease activity and precipitated calcium carbonate.To understand the scale dependency of MICP treatment,a large-scale heterogeneous domain was subjected to variable biochemical injection strategies.The simulations conducted at the field-scale guided the selection of an injection strategy to achieve the desired type and amount of precipitation.Additionally,the study emphasized the potential of numerical models as reliable tools for optimizing future developments in field-scale MICP treatment.The present study demonstrates the potential of this numerical framework for designing and optimizing the MICP applications in laboratory-,prototype-,and field-scale scenarios. 展开更多
关键词 MULTIPHYSICS Microbially induced calcite precipitation(MICP) Coupled thermo-bio-chemo-hydraulic(TBCH) model OpenGeoSys(OGS) influence factors
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Short-term inbound rail transit passenger flow prediction based on BILSTM model and influence factor analysis
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作者 Qianru Qi Rongjun Cheng Hongxia Ge 《Digital Transportation and Safety》 2023年第1期12-22,共11页
Accurate and real-time passenger flow prediction of rail transit is an important part of intelligent transportation systems(ITS).According to previous studies,it is found that the prediction effect of a single model i... Accurate and real-time passenger flow prediction of rail transit is an important part of intelligent transportation systems(ITS).According to previous studies,it is found that the prediction effect of a single model is not good for datasets with large changes in passenger flow characteristics and the deep learning model with added influencing factors has better prediction accuracy.In order to provide persuasive passenger flow forecast data for ITS,a deep learning model considering the influencing factors is proposed in this paper.In view of the lack of objective analysis on the selection of influencing factors by predecessors,this paper uses analytic hierarchy processes(AHP)and one-way ANOVA analysis to scientifically select the factor of time characteristics,which classifies and gives weight to the hourly passenger flow through Duncan test.Then,combining the time weight,BILSTM based model considering the hourly travel characteristics factors is proposed.The model performance is verified through the inbound passenger flow of Ningbo rail transit.The proposed model is compared with many current mainstream deep learning algorithms,the effectiveness of the BILSTM model considering influencing factors is validated.Through comparison and analysis with various evaluation indicators and other deep learning models,the results show that the R2 score of the BILSTM model considering influencing factors reaches 0.968,and the MAE value of the BILSTM model without adding influencing factors decreases by 45.61%. 展开更多
关键词 Rail transit passenger flow predict Time travel characteristics BILSTM influence factor Deep learning model
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Review on the decomposition and influence factors of coarse woody debris in forest ecosystem 被引量:10
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作者 ZHOU Li DAI Li-min +1 位作者 GU Hui-yan ZHONG Lei 《Journal of Forestry Research》 SCIE CAS CSCD 2007年第1期48-54,共7页
Coarse woody debris (CWD) is an important and particular component of forest ecosystems and is extremely important to forest health. This review describes the decomposition process, decomposition model and influence... Coarse woody debris (CWD) is an important and particular component of forest ecosystems and is extremely important to forest health. This review describes the decomposition process, decomposition model and influence factors. CWD decomposition is a complex and continuous process and characterizes many biological and physical processes, including biological respiration, leaching, and fragmentation. All these processes have closed relationships between each other and work synergistically. During decomposition, there are many controlling factors mainly including site conditions (temperature, humidity, and OJCO2concentration), woody substrate quality (diameter, species and compound) and organism in CWD. The decomposition rate is generally expresses through a constant k which indicate the percent mass, volume or density loss over time, and can be determined by long-term monitoring, chronosequence approach and the radio between input and the total mass. Now using mathematical models to simulate decomposition patterns and estimate the decomposition rate is widely applied, especially the exponential model. We brought forward that managing and utilizing for the CWD in forest was a primary objective on all forest lands. And it is should be intensified to integrate many related research subjects and to carry a comprehensive, long-term and multi-scale research which mainly focus on seven sections. 展开更多
关键词 Coarse woody debris Decomposition Forest ecosystem influence factors
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The influence factors of gas-bearing and geological characteristics of Niutitang Formation shale in the southern margin of Xuefeng Mountain ancient uplift: A case of Well Huangdi 1 被引量:4
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作者 Ming-na Ge Ke Chen +2 位作者 Xiang-lin Chen Chao Wang Shu-jing Bao 《China Geology》 2020年第4期533-544,共12页
In order to evaluate the geological characteristics and gas-bearing factors of Niutitang Formation within the Lower Cambrian of northern Guizhou,the Huangping area located at the southern edge of the ancient uplift be... In order to evaluate the geological characteristics and gas-bearing factors of Niutitang Formation within the Lower Cambrian of northern Guizhou,the Huangping area located at the southern edge of the ancient uplift belt of Xuefeng Mountain was selected as the target area,and Well Huangdi 1 was drilled for the geological survey of shale gas.Through geological background analysis and well logging and laboratory analysis such as organic geochemical test,gas content analysis,isothermal adsorption,and specific surface area experiments on Well Huangdi 1,the results show that the Niutitang Formation is a deep-water shelf,trough-like folds and thrust fault.The thickness of black shale is 119.95 m,of which carbonaceous shale is 89.6 m.The average value of organic carbon content is 3.55%,kerogen vitrinite reflectance value is 2.37% and kerogen type is sapropel-type.The brittle mineral content is 51%(quartz 38%),clay mineral content is 38.3%.The value of porosity and permeability are 0.5%and 0.0014 mD,which the reservoir of the Niutitang Formation belongs to low permeability with characteristics of ultra-low porosity.The gas content is 0.09‒1.31 m^3/t with a high-value area and a second high-value area.By comparing with the geological parameters of adjacent wells in the adjacent area,the accumulation model of“sediment control zone,Ro control zone,structure controlling reservoir”in the study area is proposed.Therefore,deep-water shelf-slope facies,Ro is between high maturity-early stage of overmaturity and well-preserved zones in the Niutitang Formation in this area are favorable direction for the next step of shale gas exploration. 展开更多
关键词 Shale gas Gas-bearing Well Huangdi 1 influence factors Niutitang Formation Xuefeng Mountain ancient uplift Oil and gas exploration engineering Lower Cambrian Guizhou Province China
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Study on Influence Factors of Pressure Injury Risk in the Elderly Inpatients with Kidney Disease Based on LASSO Regression 被引量:4
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作者 Ling Liu Chunhua Wang +5 位作者 Lianghong Yin Jiayi Wang Hong Yang Yingxue Zhong Zhiwei Mou Yu Chen 《Open Journal of Preventive Medicine》 2020年第6期95-107,共13页
<strong>Objective</strong>: This paper aims to explore clinical status and related influence factors of pressure injury (PI) in the elderly inpatients with kidney disease, so as to provide reference for th... <strong>Objective</strong>: This paper aims to explore clinical status and related influence factors of pressure injury (PI) in the elderly inpatients with kidney disease, so as to provide reference for the prevention and treatment of PI in the elderly inpatients with kidney disease. <strong>Methods</strong>: Retrospective collection method is adopted to collect 158 clinical cases of the elderly inpatients with kidney disease aged ≥ 60 in the Nephrology Department, the First Affiliated Hospital of Jinan University from January 2017 to December 2019, and then least absolute shrinkage and selection Operator (LASSO) regression analysis is used to analyze 17 possible influence factors;finally Logistic regression model is established to analyze and screen influence factors of risk. <strong>Results</strong>: 1) Among 158 elderly inpatients with medium and high risk of PI, the incidence of PI is 20.25%;the most common stage of injury is stage I (42.5%);sacrococcygeal (60%) is the high-risk site of pressure injury. 2) LASSO regression analysis shows that history of present respiratory infection/respiratory failure (<em>β </em>= 1.2714. <em>P</em> < 0.05) and hospitalization time (<em>β</em> = 0.4177. <em>P </em>< 0.05) are independent factors influencing PI risk in the elderly inpatients with kidney disease. <strong>Concl</strong><strong>usio</strong><strong>n</strong>: The elderly patients with kidney disease and PI risk are the high incidence population of hospital acquired PI;for the elderly inpatients with kidney disease and having respiratory infection history or respiratory failure, prolonged hospitalization will significantly increase the risk of PI. Therefore, targeted preventive and control measures should be taken to reduce the incidence of PI. 展开更多
关键词 Least Absolute Shrinkage and Selection Operator The Elderly Inpatients with Kidney Disease Pressure Injury influence factors NURSING
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The Need and Its Influence Factors for Community-based Rehabilitation Services for Disabled Persons in One District in Beijing 被引量:1
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作者 HONG DAI HUI XUE +1 位作者 ZONG-JIE YIN AND ZHONG-XIN XIAO 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2006年第6期495-497,共3页
Purpose To explore the needs for basic community-based rehabilitation services for disabled persons in Xuanwu District, Beijing, China, and to identify factors which influence disabled persons to accept rehabilitation... Purpose To explore the needs for basic community-based rehabilitation services for disabled persons in Xuanwu District, Beijing, China, and to identify factors which influence disabled persons to accept rehabilitation services. Method One hundred and eight disabled persons were selected by systematic sampling and simple random sampling to assess their needs for community-based rehabilitation services. Results Of the interviewees, 57A% needed the community-based rehabilitation services, but only 13.9% took advantage of it. The main factors influencing the interviewees to accept these services were cost (P〈0.05), knowledge about rehabilitation medicine (P〈0.05); and the belief in the therapeutic benefit of the community-based rehabilitation service (P〈0.05). Conclusion A considerable gap exists between the supply of community-based rehabilitation services in Beijing and the needs for these services by disabled residents underscoring the need for improved availability, and for additional research. 展开更多
关键词 DISABLED Rehabilitation services influence factors Functional Independence Measure (FIM)
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Influence factors for successful corneal donation among Chinese adults: data from Nanjing between 2001 and 2012 被引量:1
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作者 Li-Xun Chen Qing-Huai Liu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2014年第6期984-987,共4页
AIM: To investigate the factors that may influence the successful corneal donation among adults in China.METHODS: This retrospective study was conducted in2012. The eligible participants were all the adults registered... AIM: To investigate the factors that may influence the successful corneal donation among adults in China.METHODS: This retrospective study was conducted in2012. The eligible participants were all the adults registered in Nanjing Red Cross Eye Bank to donate their corneas after death during the period of 2001 and 2012.Multivariate logistic regression models were applied to investigate the influence factors for successful donation,the outcome events. RESULTS: Totally, 210 of 328(64.0%) registered potential donors successfully donated their corneas after death. The mean(SD) age at registration was 64.7(12.5)for all participants, with 65.5(10.1) and 63.2(15.8) for successful and unsuccessful donors, respectively. With multivariate logistic regression analysis, five factors, the willingness of donation, age, education level, residence area, and cause of death were identified to be associated with successful corneal donation.CONCLUSION: The willingness of donation and some socio-demographic factors might substantially affect their successful donation after death for people who registered to donate corneas. 展开更多
关键词 cornea donation influence factors China
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Influence Factors of Phosphorus Removal by Chemical Method in Sewage Treatment System 被引量:1
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作者 Dan Song Subo Yang 《Meteorological and Environmental Research》 CAS 2013年第7期50-52,共3页
[Objective] The research aimed to study influence factors of phosphorus removal by chemical method in sewage treatment system. [ Method] In different reaction systems, removal effect of the phosphorus in sewage by dos... [Objective] The research aimed to study influence factors of phosphorus removal by chemical method in sewage treatment system. [ Method] In different reaction systems, removal effect of the phosphorus in sewage by dosing lime and influence of the constraint factor were stud- ied. [ Result] Lime precipitation method treating high-concentration phosphorus wastewater could not only decline cost of phosphorus removal by chemical method, but also reach better treatment effect under suitable stirring and precipitation conditions by controlling alkalinity and pH. Phosphor- us content of chemical sludge after treatment could reach 9% -12%, with higher recyclable value. E Conclusion] Lime method treating phosphorus- rich sewage was more economic than low-concentration phosphorus sewage, and had very great potential for recycling phosphorus. 展开更多
关键词 Lime method Removal effect of phosphorus influence factor Sewage treatment system China
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Hydrolysis kinetics of atrazine and influence factors
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作者 LEI Zhi-fang YE Chang-ming WANG Xing-jun 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2001年第1期99-103,共5页
The hydrolysis kinetics of atrazine in distilled water and leaching water from soil, and they influence factors were studied by incubation at 35degreesC and HPLC analysis method. The kinetic process of atrazine hydrol... The hydrolysis kinetics of atrazine in distilled water and leaching water from soil, and they influence factors were studied by incubation at 35degreesC and HPLC analysis method. The kinetic process of atrazine hydrolysis can be described by the first-order reaction law. The results showed that the hydrolysis rate constants k in leaching water and distilled water were 1.606 x 10(-3)/d and 1.055 x 10(-3)/d, respectively; the half-life of atrazine hydrolysis in distilled water at pH 3, pH 4.5 and pH 8 were 373 days, 522 days and 657 days respectively. The results also showed that the proton in reaction solution can catalyze the atrazine hydrolysis; humic acid and NH4+ etc. substances in aqueous solution can facilitate atrazine hydrolysis; rate constants of atrazine hydrolysis with humic acid and NH4NO3 were 2.431 X 10(-3)/d and 1.498 X 10(-3)/d respectively which were 2.3 and 1.42 times of control(1.055 X 10(-3)/d); anion NO3- can inhibit catalysis of humic acid to atrazine hydrolysis. 展开更多
关键词 ATRAZINE hydrolysis kinetics influence factors
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Influence factors on the ground surface rupture zone induced by buried normal fault dislocation
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作者 Jianfeng Qi Fengjunnan Liu +1 位作者 Xiangyu Yang Yang Zhao 《Earthquake Science》 2020年第2期62-71,共10页
The seismic disaster presents a zonal distribution along the fault strike.In this paper,rupture zone of ground surface soil caused by the uniform dislocation,inclined dislocation and warped dislocation of buried norma... The seismic disaster presents a zonal distribution along the fault strike.In this paper,rupture zone of ground surface soil caused by the uniform dislocation,inclined dislocation and warped dislocation of buried normal fault are studied by constituting a three-dimensional finite element model in Automatic Dynamic Incremental Nonlinear Analysis(ADINA).According to the critical value of surface rupture,the variational features and influencing factors of width and starting position of the"avoiding zone"in engineering construction are analyzed by using 96 model calculations.The main results are as follows:(1)Since the rupture zone of the ground surface soil from the point of mechanics is different from the"avoidance zone"from the point of engineering safety,the equivalent plastic strain and the total displacement ratio should be considered to evaluate the effect of the seismic ground movement on buildings.(2)During fault dislocation,plastic failure firstly occurred on the ground surface soil of the footwall side,and then the larger deformation gradually moved to the side of the hanging wall of the fault with the increase of fault displacement.(3)When the vertical displacement of buried fault reaches 3 m,the width of"avoiding zone"in engineering construction varies within the range of 10-90 m,which is most affected by the thickness of overlying soil and the dip angle of the fault. 展开更多
关键词 buried normal fault surface rupture avoiding zone numerical simulation influence factors
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Analysis on the Climatic Change Characteristics of the Snow Cover Days and Its Influence Factors in Suzhou during Recent 50 Years
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作者 ZHAO Xue-song WANG Dong ZHOU Gui-bin 《Meteorological and Environmental Research》 CAS 2011年第9期40-42,共3页
[Objective] The research aimed to study climatic variation characteristics of snow cover days and its influence factors in Suzhou of Anhui Province during recent 50 years. [Method] According to annual snow cover days ... [Objective] The research aimed to study climatic variation characteristics of snow cover days and its influence factors in Suzhou of Anhui Province during recent 50 years. [Method] According to annual snow cover days and correlated data in Suzhou during 1961-2010, by using linear trend method, accumulative anomaly and complete correlation coefficient method, etc., the climatic variation characteristics of snow cover days and its influence factors in Suzhou were analyzed. [Result] In recent 50 years, the snow cover period in Suzhou presented shortened trend. Except days of snow cover (≥20 cm), the annual snow cover days at each thickness all showed varying degrees of decrease trend. The annual snow cover days had wavy decline trend, and the decline amplitude was 0.84 d/10 a. From the 1960s to prior period of the 1970s, the annual snow cover days presented increase trend. From middle and later periods of the 1970s to middle period of the 1980s, the snow cover days was less and gradually increased from later period of the 1980s to the early 1990s. From middle period of the 1990s to 2003, it entered into less snow period again. From 2004 to now, it presented oscillation of snowy and less-snow alternating. The main climatic factor which affected annual snow cover days in Suzhou was average temperature. The second one was average surface temperature. [Conclusion] The research provided theoretical basis for analyzing climate variation in Suzhou under the background of global climate warming. 展开更多
关键词 Snow cover days Climate change CHARACTERISTIC influence factor SUZHOU China
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Analysis on Farmers’ Straw Marketization Behavior and Its Influence Factors: A Case Study of Hubei Province
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作者 Zhanzhan ZHANG 《Asian Agricultural Research》 2017年第6期48-52,共5页
Crop straw has huge resource potential. It has an important significance for realizing waste recycling and improving eco-environment to prefect straw marketization system and sufficiently stimulate farmers’ straw mar... Crop straw has huge resource potential. It has an important significance for realizing waste recycling and improving eco-environment to prefect straw marketization system and sufficiently stimulate farmers’ straw marketization behavior. Based on 427 copies of investigation data on farmers,influence mechanism framework of farmers’ straw marketization behavior is constructed,and key factors of farmers’ straw marketization behavior are analyzed. Results show that farmers joining in straw marketization account for 42. 1%; in influence factors of farmers’ straw marketization behavior,cultivated land area,market price level,logistics satisfaction and air quality perception have significantly positive impacts on farmers’ straw marketization behavior,while education degree,agricultural income proportion and traffic convenience have significantly negative impacts on farmers’ straw marketization behavior. Therefore,it needs strengthening propaganda intensity,carrying out reasonable subsidies and support,encouraging and breeding new type of organization,and establishing and improving the price mechanism of straw marketization to perfect straw marketization construction. 展开更多
关键词 STRAW Farmers’ marketization behavior Logistic model influence factors Hubei Province
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Empirical Research on Influence Factors of "Leading Enterprise + Farmer" Channel Stability-Taking Personal Relation as the Regulated Variable
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作者 Xinxin DING Daosheng LI Mojing CHEN 《Asian Agricultural Research》 2017年第1期41-46,共6页
In the cooperation model of leading enterprise + farmer,channel stability is always a prominent problem. Based on previous researches,taking farmers in Hainan region as investigation object,the influence factors of ch... In the cooperation model of leading enterprise + farmer,channel stability is always a prominent problem. Based on previous researches,taking farmers in Hainan region as investigation object,the influence factors of channel stability of leading enterprise + farmer are studied by combining the background of formal contract and using the combination method of theory and demonstration. Contract item design,trading cost,product specificity,power structure,information asymmetry and social relationship are contained in analytic framework to establish theoretic model. Research results show that in formal channel management,when contract clause design is more explicit,product specificity is stronger,power structure is more balanced,information share degree is higher,and trading cost is lower,channel is more stable,and farmer's willing to renew contract is stronger. Meanwhile,social relationship plays stronger regulation role. 展开更多
关键词 Formal control Channel stability RELATIONSHIP influence factor
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Total Factor Productivity and Influence Factors of Economic Environment in the Yellow River Delta
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作者 SHAN Changqing 《Journal of Landscape Research》 2016年第5期93-96,共4页
The paper analyzed total factor productivity of Binzhou City, and key factors that influence its economic growth and effluent discharge. The results showed that(i) production efficiency of the city during 2005–2013 k... The paper analyzed total factor productivity of Binzhou City, and key factors that influence its economic growth and effluent discharge. The results showed that(i) production efficiency of the city during 2005–2013 kept stable, mean of Malmquist-Luenberger index was 1.044,9 without considering effluent discharge, and the average annual increase rate was 4.49%, and that was 1.020,4 considering effluent discharge, the average annual increase rate was 2.04%, and the increase rate reduced by 2.45%.(ii) GDP growth showed significant negative correlation and positive correlation with capital input and energy input, but insignificant negative correlation and positive correlation with labor force input and technological progress.(iii) Effluent discharge showed insignificant negative correlation and positive correlation with capital input and energy input, but significant negative correlation and positive correlation with labor force input and technological progress. 展开更多
关键词 The Yellow River Delta Total factor productivity Economic environment influence factor
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Study on the Key Influence Factors of Environmental Mass Incidents by Delphi-PCA-Frequency Analysis Composite Method
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作者 Chuai Xiaoming HAN Jingwen +1 位作者 Zhou Ying Wang Jiajia 《Meteorological and Environmental Research》 CAS 2018年第3期54-59,共6页
In order to prevent and control environmental mass incidents,by comprehensively using literature research,case analysis and logical reasoning method,27 factors influencing environmental mass incidents were selected. A... In order to prevent and control environmental mass incidents,by comprehensively using literature research,case analysis and logical reasoning method,27 factors influencing environmental mass incidents were selected. Among them,15 key influencing factors were screened by Delphi-PCA-frequency analysis composite method. The key influencing factors were analyzed,and corresponding countermeasures were put forward. 展开更多
关键词 Environmental mass incidents Delphi-PCA-frequency analysis Key influence factors
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Influence Factors of Farmers' Willingness to Poverty Alleviation Relocation in South Shaanxi Province 被引量:1
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作者 Liang GUO Bo YANG Yanling CHI 《Asian Agricultural Research》 2017年第12期17-22,共6页
In southern Shaanxi,far from the core areas of politics and economy,the conditions are inconvenient and farmers have been threatened by geology,floods for many years,resulting in a large population of poor people.The ... In southern Shaanxi,far from the core areas of politics and economy,the conditions are inconvenient and farmers have been threatened by geology,floods for many years,resulting in a large population of poor people.The relocation of poverty alleviation project in southern Shaanxi is helpful for improving living standards of people in disaster-stricken areas.Based on the field survey,this paper analyzed 274 valid questionnaires and established a Logistic Regression Analysis Model.The result shows that the health status of head of household,road type before relocation,annual loss of disasters,and changes in the family income after relocation have a greater influence on the relocation willingness of farmers,while the educational level of householder,the distance from the original place of residence to the town and market,the condition of household electricity before relocation and other factors have a little influence on the relocation willingness of farmers. 展开更多
关键词 Disaster-stricken areas of southern Shaanxi Poverty alleviation relocation Willingness of farmers influencing factors
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A Problem Not to Be Ignored: The Influencing Factors of Mobile Phone Addiction and Its Influence on Sleep Quality
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作者 Zihan Ji Lian Zhou 《Health》 2024年第5期459-469,共11页
Background and Objective: With the popularity and widespread use of mobile phones, the effects of mobile phone dependence and addiction on individuals’ physical and mental health have attracted more and more attentio... Background and Objective: With the popularity and widespread use of mobile phones, the effects of mobile phone dependence and addiction on individuals’ physical and mental health have attracted more and more attention. The present study aims to analyze the current state of mobile phone addiction and its impact on sleep quality within the population, while also exploring the influence of related factors on sleep quality. Ultimately, this research will provide a scientific foundation for targeted intervention measures and strategies. Methods: A total of 253 permanent residents in Nanjing were randomly selected as study subjects. The Mobile Phone Addiction Index (MPAI) and Pittsburgh Sleep Quality Index (PSQI) were used to evaluate the degree of smartphone addiction and sleep quality of the study subjects. Body mass index (BMI) was measured according to standardized procedures. Independent sample t-test, Chi-square test, rank sum test and multiple linear regression were used to analyze the correlation between mobile phone addiction and sleep quality, and P Results: 117 people (46.2%) were addicted to mobile phones. Chi-square test showed that the rate of mobile phone addiction in drinking group was significantly higher than that in non-drinking group (P P P P P P P P P P Conclusion: Mobile phone addiction may lead to shorter sleep duration and reduce sleep efficiency. The withdrawal of mobile phone addiction may have a negative impact on sleep quality. According to the characteristics of the population, appropriate comprehensive intervention measures should be taken to build an effective evaluation system, so as to reduce the impact of mobile phone addiction and withdrawal problems on sleep and improve sleep quality. 展开更多
关键词 Mobile Phone Addiction Influencing factors WITHDRAWAL Sleep Quality
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Numerical study on the wave pattern characteristic of air layer in cavity and the effects of multiple influence factors
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作者 Xiao-song Zhang Xue-qin Ji +3 位作者 Lei-qiang Chen Li-jin Gao Hong-bo Huang Fang-wen Hong 《Journal of Hydrodynamics》 SCIE EI CSCD 2023年第5期923-941,共19页
Air-layer drag reduction (ALDR) technology for ship energy saving is getting more and more attention in recent years because of the outstanding drag reduction effect. In order to promote practical application, it is n... Air-layer drag reduction (ALDR) technology for ship energy saving is getting more and more attention in recent years because of the outstanding drag reduction effect. In order to promote practical application, it is necessary to fully understand the two phase flow characteristics of the air layer. Recent experimental studies have shown that the surface of the air layer presents wave pattern, which has an important influence on its damage risk. However, it is difficult to measure the wave pattern quantificationally due to the interference of equipment. The main goal of the present paper is to investigate the wave pattern characteristic of air layer in cavity using numerical simulation method. On this basis, the effect of flow and geometric influence factors are discussed to understand the key control conditions. A computational fluid dynamics (CFD) numerical method based on Reynolds averaged Navier-Stokes (RANS) equations and volume of fluid (VOF) interface capturing method is established, and has been successfully applied in the simulation of air layer wave pattern. Both 2-D and 3-D simulations are carried out, aiming at analyzing air-water interface flow and vortex flow directly. Based on the simulation results, several important conclusions about the mechanism of air layer wave pattern can be obtained. Firstly, it is found to be an inherent characteristic that the wave height of the upstream air layer is higher than that of the downstream. The extremely high wave peak is easy to contact with the flat plate, leading to the breakup of air layer and a “central blank area” phenomenon. With the help of flow analysis, it is found that this characteristic is mainly caused by the strong counterclockwise vortex behind the bow wedge block. Secondly, the air layer stability is reduced with the increase of water flow velocity by affecting the wave height. There is a saturation point of air flow rate to reach maximum thickness of air layer. Thirdly, cavity configuration has obvious influence on air layer stability by influencing vortex flow field. The increase of cavity depth and width can aggravate the unsteady and nonlinear characteristics of air layer. Finally, comprehensive design criteria are concluded from the view of geometrical configuration and flow conditions. A cavity with the moderate depth and width can avoid the upstream damage of air layer. Longitudinal position of air nozzles should be set within the low pressure zone behind the wedge block for stable air layer formation. 展开更多
关键词 Air layer drag reduction wave pattern of air-water interface numerical simulation multiple influence factors vortex flow fields
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Quantitative Evaluation of Heavy Metal Pollution and Its Influencing Factors in Water Bodies of Karst Areas
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作者 Dijin MU Shizhen XIAO 《Meteorological and Environmental Research》 2024年第1期75-82,共8页
At present, there is relatively little research on the synergistic effects of heavy metals in soil, sediment, and bedrock on heavy metal pollution in water bodies. In this paper, heavy metals in soil, sediment, bedroc... At present, there is relatively little research on the synergistic effects of heavy metals in soil, sediment, and bedrock on heavy metal pollution in water bodies. In this paper, heavy metals in soil, sediment, bedrock, and water of a typical karst watershed in southwest China were investigated. The results indicated that the average values of heavy metals in soil and sediment were relatively higher than those in bedrock except for Ni and As. During the research period, As and Cd were the main heavy metal elements polluting the soil and sediment in the study area, while water bodies were mainly polluted by Ni, As, and Cd. The pollution assessment indicated that there were instances of poor or very poor water quality in the study area during the study period;the soil as a whole was slightly polluted by Cd and As;sediment was subject to moderate Cd pollution and mild As pollution. Analysis of geochemical form for heavy metals showed that heavy metals in soil and sediment were mainly in residual form, and the proportions of exchangeable As and Cd were relatively high. Multiple statistical analysis showed that heavy metals in sediment, soil, and bedrock explained 23.8%, 16.8%, and 16.2% of the changes in heavy metals of water, respectively. The research results can provide scientific basis for the prevention and control of heavy metal pollution in water bodies. 展开更多
关键词 Water body SEDIMENT Soil BEDROCK Speciation forms POLLUTION influence factor
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Factors affecting land dissection density in geomorphological regions of China
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作者 SUN Xiaolin ZHAO Yinjun +4 位作者 PENG Peihao CHENG Weiming WEI Yongping YANG Ronghao LI Jiaxu 《Journal of Mountain Science》 SCIE CSCD 2024年第4期1372-1387,共16页
Land dissection density(LDD)provides morphological evidence regarding prior intense soil erosion and quantifies the distribution of land dissections.A comprehensive understanding of the potential factors influencing t... Land dissection density(LDD)provides morphological evidence regarding prior intense soil erosion and quantifies the distribution of land dissections.A comprehensive understanding of the potential factors influencing the spatial pattern and value of the LDD is vital in geological disasters,soil erosion,and other related domains.Land dissection phenomena in China affects large areas with different morphological,pedological,and climatic characteristics.Prior studies have focused on the potential factors influencing the LDD at a watershed scale.However,these results are insufficient to reflect the status quo of dissection development and its primary influencing factors on a national scale.LDD’s spatial patterns and the dominant factors at a regional scale in millions of square kilometers remain to be ascertained.This study used the geomorphon-based method and the geographical detector model to quantify the spatial pattern of LDD over China and identify the dominant factors affecting this pattern in China’s six first-order geomorphological regions(GR1~GR6).The results yield the following findings:(1)LDD in China ranges from 0~4.55 km/km^(2),which is larger in central and eastern regions than in other regions of China;(2)dominant factors and their dominant risk subcategories vary with each geomorphological region’s primary internal and external forces;(3)the influence of natural factors is more significant on the large regional scale in millions of square kilometers compared to anthropogenic factors;relief degree of land surface(RDLS)is dominant in GR1,GR2,and GR5;the slope is dominant in GR6,soil type is dominant in GR3 and GR4,and lithology plays a critical role in the dominant interactions of GR3,GR4,and GR6;(4)the interactions between factors on LDD’s spatial pattern have a more significant effect than individual factors. 展开更多
关键词 Land dissection density Influencing factors Regional scale Spatial pattern Geographical detector model Geomorphon-based method China
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