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Effects of protein properties on ultrafiltration membrane fouling performance in water treatment
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作者 Yanyan Ding Baiwen Ma +1 位作者 Huijuan Liu Jiuhui Qu 《环境科学学报:英文版》 SCIE EI CAS CSCD 2019年第3期273-281,共9页
Protein-like substances always induce severe ultrafiltration(UF) membrane fouling. To systematically understand the effect of proteins, regenerated cellulose UF membrane(commonly used for protein separation) performan... Protein-like substances always induce severe ultrafiltration(UF) membrane fouling. To systematically understand the effect of proteins, regenerated cellulose UF membrane(commonly used for protein separation) performance was investigated in the presence of bovine serum albumin(BSA) under various water conditions. Results showed that although trypsin enhanced the membrane flux via proteolysis, catalysis took a long time. Membrane fouling was alleviated at high solution p H and low water temperature owing to the strong electrostatic repulsion force among BSA molecules. Both Na+ and Ca2+could increase membrane flux. However, Ca2+played a bridging role between adjacent BSA molecules,whereas membrane fouling was alleviated via a hydration repulsion force with Na+. The order of influence on membrane fouling was as follows: Ca2+concentration > Na+concentration > pH > temperature > trypsin concentration. Furthermore, a polyvinylidene fluoride UF membrane experiment showed that Ca2+could reduce the fouling induced by BSA. Thus, the differences in UF membrane performance will have application potential for alleviating UF membrane fouling induced by proteins during water treatment. 展开更多
关键词 ULTRAFILTRATION MEMBRANE Protein PROPERTIES Influencing FACTORS MEMBRANE PERFORMANCE
Survey on Factors Influencing the Decline in Chicken Consumption of Urban Residents in Liaoning Province 预览
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作者 Na DING Chunling PAN +1 位作者 Zhe ZHANG Shanshan GAO 《亚洲农业研究:英文版》 2019年第4期11-16,共6页
In order to analyze the key factors influencing the decline in chicken consumption in urban residents in Liaoning Province since2008,and understand the characteristics of chicken consumption behavior of consumers in L... In order to analyze the key factors influencing the decline in chicken consumption in urban residents in Liaoning Province since2008,and understand the characteristics of chicken consumption behavior of consumers in Liaoning Province,this paper used questionnaire survey to analyze the consumption of chicken and chicken products in Shenyang,Dalian,Anshan and Benxi of Liaoning Province. According to the analysis,the main reason for the decline in the chicken consumption is that the growth of pork consumption quickly replaced part of chicken consumption,which may be caused by the consumption preference of local residents. Another important reason is the frequent occurrence of incidents of chicken food quality and safety,leading to the worry about the safety of chicken food and accordingly reducing the times of chicken consumption. In addition,compared with the pork,beef,and mutton,the taste of chicken is slightly worse. In the period of consumption upgrading,the growth and decline of a product is a common phenomenon. 展开更多
关键词 CHICKEN and CHICKEN products CONSUMPTION quantity CONSUMPTION characteristics Influencing FACTORS
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Spatio-temporal evolution of ecologically-sustainable land use in China’s Loess Plateau and detection of its influencing factors
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作者 QU Lu-lu LIU Yan-sui CHEN Zong-feng 《山地科学学报:英文版》 SCIE CSCD 2019年第5期1065-1074,共10页
Ecological land(Eco-land) is a basic resource for human beings to survive, and eco-land use is a strategy, a way to manage the land resource. So, ecologically-sustainable land use is essential for human beings to surv... Ecological land(Eco-land) is a basic resource for human beings to survive, and eco-land use is a strategy, a way to manage the land resource. So, ecologically-sustainable land use is essential for human beings to survive. This paper investigates the spatiotemporal characteristics and mechanisms of urban-rural eco-land using a new and innovative integration way based on eco-land change data in China’s Loess Plateau(LP) prefecture level cities and explores factors of eco-land change. The spatial difference characteristic of eco-land among different level cities in the LP is that: small cities > big cities > middle cities. From 2009 to 2016, the eco-land in the LP from the perspective of urban-rural areas has changed significantly. Significant differences of urban-rural eco-land were identified among various urban growth types, and all the cities in the LP were further classified into four types based on eco-land change trend, with type A and B cities identified as the vital zone and major zone. Taking the eco-fragile region Loess Plateau(LP) as an example, our results demonstrated that the migrants to cities in LP could relieve ecological pressures and promote restoration of ecological vegetation. We have demonstrated that urbanization and the influence of government policy can be discerned through the quantification of the spatial-temporal change of eco-land and suggest that combining both urban and rural eco-land can support more effective land use decisions and provide theoretical basis for the practical application of urban planning, policy-making and sustainable development. What’s more, governments should strive to population mobility and restore vegetation to sustain this fragile ecological environment. 展开更多
关键词 Ecologically-sustainable land use SPATIO-TEMPORAL EVOLUTION influencing factor Population migration LOESS PLATEAU
Quality of Life and its Influencing Factors in Urban Elderly Patients with Chronic Diseases 预览
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作者 Jun Zheng Hong Zhao Xinru Wu 《老年医学(英文)》 2019年第1期22-24,共3页
Objective: To analyze and discuss the quality of life of elderly patients with chronic diseases and its influencing factors. The aim of this study was to provide a theoretical basis for targeted intervention of influe... Objective: To analyze and discuss the quality of life of elderly patients with chronic diseases and its influencing factors. The aim of this study was to provide a theoretical basis for targeted intervention of influencing factors of chronic diseases and improvement of the quality of life of patients. Methods: A total of 1000 elderly patients with chronic diseases in our health center were randomly selected as the study subject. Questionnaire survey was conducted by self-designed questionnaire. The SF-36 quality of life scale was used to evaluate their quality of life;and linear regression model was used to explore the relevant influencing factors. Result: The SF-36 score showed that there was a correlation between the six dimensions, including overall health, physiological function, somatic pain, vitality, social function and mental health, and the number of chronic diseases in elderly patients. With the increase of chronic diseases, the scores of each dimension showed a downward trend. Linear regression analysis showed that age, anxiety and poor sleep quality were the main factors affecting the quality of life in elderly patients with chronic diseases. Conclusion: The quality of life of elderly patients with chronic diseases in our city is poor. In community work, targeted nursing and intervention should be given according to the types of diseases suffered by the elderly. 展开更多
关键词 ELDERLY patients with CHRONIC DISEASES Quality of life Influencing FACTORS
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Dynamic changes in lakes in the Hoh Xil region before and after the 2011 outburst of Zonag Lake
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作者 LIU Wen-hui XIE Chang-wei +6 位作者 ZHAO Lin WU Tong-hua WANG Wu ZHANG Yu-xin YANG Gui-qian ZHU Xiao-fan YUE Guang-yang 《山地科学学报:英文版》 SCIE CSCD 2019年第5期1098-1110,共13页
Zonag, Kusai, Hedin Noel and Yanhu Lakes are independent inland lakes in the Hoh Xil region on the Qinghai-Tibet Plateau. In September2011, Zonag Lake burst after the water level had increased for many years. Floods f... Zonag, Kusai, Hedin Noel and Yanhu Lakes are independent inland lakes in the Hoh Xil region on the Qinghai-Tibet Plateau. In September2011, Zonag Lake burst after the water level had increased for many years. Floods flowed through Kusai and Hedin Noel Lakes into Yanhu Lake;since then, the four small endorheic catchments merged into one larger catchment. This hydrological process caused the rapid shrinkage of Zonag Lake and continuous expansion of Yanhu Lake. In this study,based on satellite images, meteorological data and field investigations, we examined the dynamic changes in the four lakes and analyzed the influencing factors. The results showed that before 2011, the trends in the four lake areas were similar and displayed several stages. The change in the area of Zonag Lake corresponded well to the change in annual precipitation(AP), but the magnitude of the change was less than that of a non-glacier-fed lake. Although increased precipitation was the dominant factor that caused Zonag Lake to expand, increased glacier melting and permafrost thawing due to climate warming also had significant effects. After the 2011 outburst of Zonag Lake, due to the increasing AP and accelerating glacier melting, the increases in water volume of the three lakes were absorbed by Yanhu Lake, and Yanhu Lake expanded considerably. According to the rapid growth rates in water level and lake area, Yanhu Lake is likely to burst in 1-2 years. 展开更多
关键词 Dynamic CHANGE LAKE areas Influencing factors GLACIER CHANGE PERMAFROST thawing Zonag LAKE
Review of Factors Influencing Active Components of Lonicera japonica Thunb. 预览
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作者 Ya SU Yi PEI +5 位作者 Wenjun SUN Yuejun ZHANG Lei ZHAO Changzhong DING Jiangli NIE Baiming WANG 《药用植物研究(英文版)》 2019年第4期5-8,共4页
Lonicera japonica Thunb. is a typical medicinal and edible plant in China. It has antibacterial, anti-oxidant, anti-endotoxin, and anti-inflammatory effects, etc. Its pharmacological action is closely related to its a... Lonicera japonica Thunb. is a typical medicinal and edible plant in China. It has antibacterial, anti-oxidant, anti-endotoxin, and anti-inflammatory effects, etc. Its pharmacological action is closely related to its active components. Based on the results of previous studies, this paper summarized the effects of variety, origin, cultivation conditions, pruning, harvesting period and processing methods on the active components of L. japonica , in the hope of providing theoretical guidance for high-yield and high-quality cultivation of L. japonica. 展开更多
关键词 LONICERA JAPONICA Thunb. ACTIVE COMPONENTS Influencing FACTORS
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Inventory and Spatial Distribution of Landslides Triggered by the 8th August 2017 M_W 6.5 Jiuzhaigou Earthquake, China
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作者 Yingying Tian Chong Xu +3 位作者 Siyuan Ma Xiwei Xu Shiyuan Wang He Zhang 《地球科学学刊:英文版》 SCIE CAS CSCD 2019年第1期206-217,共12页
An accurate and detailed seismic landslide inventory is essential to better understand the landslide mechanism and susceptibility. The 8 th August 2017 MW 6.5 Jiuzhaigou Earthquake of China initiated a large number of... An accurate and detailed seismic landslide inventory is essential to better understand the landslide mechanism and susceptibility. The 8 th August 2017 MW 6.5 Jiuzhaigou Earthquake of China initiated a large number of coseismic landslides. The results of the post-seismic survey show the actual landslide number might be underestimated in previous publications. Coupled with field investigation and visual interpretation on high-resolution remote sensing images before and after the main shock, we established a detailed inventory of landslides triggered by the earthquake. Results show that this event caused at least 4 834 individual landslides with a total area of 9.64 km^2. They are concentrated in an elliptical area of 434 km^2, dominated by medium-and small-scale rock falls and debris slides. Statistics indicate that, except for slope aspect that seems not significantly correlated with the landsliding, these landslides are most common in the places with following features: elevation of 2 800–3 400 m, slope angle greater than 30°, slope positions of upper, middle and flat slopes, and Carboniferous limestone and dolomite. Besides, the landslide area percentage(LAP) and landslide number density(LND) values decrease with the increasing distance to river channels and roads, implying a positive correlation. Instead of centering around the epicenter, most of these coseismic landslides are distributed along the inferred seismogenic fault, which means that the seismogenic structure played a more important role than the location of the epicenter. Remarkable differences in landslide densities along the fault indicate the varied landslide susceptibility which may be attributed to other varied controls along the fault such as the rock mass strength. In sum, this study presents a more detailed inventory of the landslides triggered by the 2017 MW 6.5 Jiuzhaigou Earthquake, describes their distribution pattern and analyzes its control factors, which would be helpful to understand the genesis of the coseismic landslides and furt 展开更多
关键词 Jiuzhaigou EARTHQUAKE COSEISMIC LANDSLIDE LANDSLIDE INVENTORY influencing factors spatial distribution
Myocardial bridge-related coronary heart disease:Independent influencing factors and their predicting value 预览
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作者 Dong-Hui Zhao Qian Fan +2 位作者 Jun-Xia Ning Xin Wang Jia-Yu Tian 《世界临床病例杂志》 2019年第15期1986-1995,共10页
BACKGROUND Myocardial bridge(MB)will compress the mural coronary artery(MCA)during the systole and cause myocardial ischemia.In the diagnosis of coronary heart disease(CHD),because the structure of MB is difficult to ... BACKGROUND Myocardial bridge(MB)will compress the mural coronary artery(MCA)during the systole and cause myocardial ischemia.In the diagnosis of coronary heart disease(CHD),because the structure of MB is difficult to be observed by coronary angiography(CAG),the clinical study of the influence of MB on CHD is lacking.With the advancement of computed tomography coronary angiography technology,detailed observations of the MB anatomy have realized.AIM To explore the main influencing factors of MB-related CHD and to find potential indicators for predicting MB-related CHD.METHODS A total of 1718 patients with suspected CHD due to the symptoms of myocardial ischemia were enrolled as subjects.Patients diagnosed with CHD were included in a CHD group,and patients with no significant abnormalities were included in a control group.In the CHD group,patients were divided into an MB-CHD subgroup if MB-related CHD was found.In the control group,patients were divided into a simple MB subgroup if MB was found.The patient's clinical data and MB-related indicators,including the branch of MB,MB type(superficial/deep type),MB length,MB thickness,systolic and diastolic compression of the MCA,and MCA systolic stenosis rate were recorded and compared.Logistic regression analysis was used to explore the independent influencing factors of MD-related CHD.ROC curve was used to analyze the diagnostic efficacy of potential indicators for MB-related CHD.RESULTS There were 1060 cases in the CHD group and 658 cases in the control group,and there were 236 cases in the MB-CHD subgroup and 52 cases in the simple MB subgroup.Multivariate logistic regression analysis showed that the combined MB had a significant effect on the occurrence of CHD(P<0.05).MB thickness,systolic compression,diastolic compression,and MCA systolic stenosis rate had significant effects on the occurrence of MB-related CHD(P<0.05).The area under the curve(AUC)of the combination of these influencing factors for the diagnosis of MB-related CHD was 0.959,which was significantly hig 展开更多
关键词 Myocardial bridge CORONARY heart disease MURAL CORONARY artery COMPUTED tomography CORONARY ANGIOGRAPHY INDEPENDENT influencing factor
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Prediction Model of Coal Reservoir Pressure and its Implication for the Law of Coal Reservoir Depressurization 预览
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作者 YAN Xinlu ZHANG Songhang +5 位作者 TANG Shuheng LI Zhongcheng WANG Kaifeng YI Yongxiang DANG Feng HU Qiuping 《地质学报:英文版》 SCIE CAS CSCD 2019年第3期692-703,共12页
The main methods of coalbed methane(CBM)development are drainage and depressurization,and a precise prediction of coal reservoir pressure is thus crucial for the evaluation of reservoir potentials and the formulation ... The main methods of coalbed methane(CBM)development are drainage and depressurization,and a precise prediction of coal reservoir pressure is thus crucial for the evaluation of reservoir potentials and the formulation of reasonable development plans.This work established a new reservoir pressure prediction model based on the material balance equation(MBE)of coal reservoir,which considers the self-regulating effects of coal reservoirs and the dynamic change of equivalent drainage area(EDA).According to the proposed model,the reservoir pressure can be predicted based on reservoir condition data and the actual production data of a single well.Compared with traditional reservoir pressure prediction models which regard EDA as a fixed value,the proposed model can better predict the average pressure of reservoirs.Moreover,orthogonal experiments were designed to evaluate the sensitivity of reservoir parameters on the reservoir pressure prediction results of this proposed model.The results show that the saturation of irreducible water is the most sensitive parameter,followed by Langmuir volume and reservoir porosity,and Langmuir pressure is the least sensitive parameter.In addition,the pressure drop of reservoirs is negatively correlated with the saturation of irreducible water and the Langmuir volume,while it is positively correlated with porosity.This work analyzed the reservoir pressure drop characteristics of the CBM wells in the Shizhuangnan Block of the Qinshui Basin,and the results show that the CBM reservoir depressurization can be divided into three types,i.e.,rapidly drop type,medium-term stability type,and slowly drop type.The drainage features of wells were reasonably interpreted based on the comprehensive analysis of the reservoir depressurization type;the latter was coupled to the corresponding permeability dynamic change characteristics,eventually proving the applicability of the proposed model. 展开更多
关键词 coalbed METHANE PRESSURE PREDICTION EQUIVALENT drainage area influencing factors PRESSURE DROP types Qinshui Basin
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Analysis of PM2.5 concentrations in Heilongjiang Province associated with forest cover and other factors 预览
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作者 Yu Zheng San Li +2 位作者 Chuanshan Zou Xiaojian Ma Guocai Zhang 《林业研究:英文版》 CAS CSCD 2019年第1期269-276,共8页
Atmospheric particulate matter(PM2.5)seriously influences air quality.It is considered one of the main environmental triggers for lung and heart diseases.Air pollutants can be adsorbed by forest.In this study we inves... Atmospheric particulate matter(PM2.5)seriously influences air quality.It is considered one of the main environmental triggers for lung and heart diseases.Air pollutants can be adsorbed by forest.In this study we investigated the effect of forest cover on urban PM2.5 concentrations in 12 cities in Heilongjiang Province,China.The forest cover in each city was constant throughout the study period.The average daily concentration of PM2.5 in 12 cities was below 75 lg/m3 during the non-heating period but exceeded this level during heating period.Furthermore,there were more moderate pollution days in six cities.This indicated that forests had the ability to reduce the concentration of PM2.5 but the main cause of air pollution was excessive human interference and artificial heating in winter.We classified the 12 cities according to the average PM2.5 concentrations.The relationship between PM2.5 concentrations and forest cover was obtained by integrating forest cover,land area,heated areas and number of vehicles in cities.Finally,considering the complexity of PM2.5 formation and based on the theory of random forestry,we selected six cities and analyzed their meteorological and air pollutant data.The main factors affecting PM2.5 concentrations were PM10,NO2,CO and SO2 in air pollutants while meteorological factors were secondary. 展开更多
关键词 FOREST COVER Heilongjiang PROVINCE Influencing factor PM2.5 CONCENTRATIONS RANDOM FOREST
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A Modified CES Production Function Model and Its Application in Calculating the Contribution Rate of Energy and Other Influencing Factors to Economic Growth 预览
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作者 Maolin CHENG Guojun SHI Yun HAN 《系统科学与信息学报:英文版》 CSCD 2019年第2期161-172,共12页
In the analysis of economic growth factors, the constant elasticity of substitution(CES)production function model is used to calculate the contribution rates of influencing factors to economic growth. However, the tra... In the analysis of economic growth factors, the constant elasticity of substitution(CES)production function model is used to calculate the contribution rates of influencing factors to economic growth. However, the traditional CES production function model fails to consider the staged characteristics of economic growth. Therefore, this study provides a modified model of the CES production function. With regard to its application, a new method for calculating the contribution rates of energy and other influencing factors to economic growth is proposed using a modified CES production function model. This work concludes by calculating the contribution rates of Chinese energy and other influencing factors to economic growth. 展开更多
关键词 CES production function influencing factors ECONOMIC growth CONTRIBUTION rate
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Analysis on influencing factors of patients experience in community health centers of Shenzhen,China 预览
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作者 CHANG Feifei CHEN Xianhui +1 位作者 HUANG Hong WANG Qiang 《中西医结合护理(中英文)》 2019年第1期224-230,共7页
Objective To investigate the patients experience in community health centers(CHCs)and explore its associated factors.Methods A cross-sectional study was conducted among 330 patients who visited CHCs in Shenzhen,China ... Objective To investigate the patients experience in community health centers(CHCs)and explore its associated factors.Methods A cross-sectional study was conducted among 330 patients who visited CHCs in Shenzhen,China from January to March 2018.Dependent variable was patient experience.Key descriptive variables were age,gender,marital status,working status groups,visits frequency for the past 6 months,whether patients had signed a family doctor,whether trusted in family doctor,whether had chronic diseases.Results Questionnaires for 300 patients were assessed.In the univariate analysis,patients experience total score was significantly associated with marital status(P<0.1),working status groups(P<0.1),frequency of visit for the past 6 months(P<0.05),whether had signed a family doctor(P<0.05),whether trusted in family doctor(P<0.05),whether had chronic diseases(P<0.05).The multivariate analysis showed that unmarried patients(P=0.011,OR=2.96,95%CI:1.24-5.43)and had signed a family doctor(P=0.023,OR=0.44,95%CI:0.22-0.85)were more likely to get a higher score.Conclusions Findings of this study showed a medium-level score of patients experience in the community.Patients had a quite good experience and more interventions should be focused upon the influence factors to improve patients experience. 展开更多
关键词 PATIENTS EXPERIENCE influencing factors COMMUNITY health CENTERS family DOCTOR chronic disease
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新疆石河子地区成年眼外伤住院患者分析
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作者 张培莉 杨炜 +2 位作者 孟新丹 李军 张芳 《中华眼外伤职业眼病杂志》 2019年第4期263-269,共7页
目的分析新疆石河子地区成年眼外伤住院患者的临床特征及预后影响因素。方法对2007年1月至2017年12月的1532例(1607眼)成年眼外伤的资料进行回顾性研究。结果眼外伤患者以青年男性、汉族为主;多在夏季户外发生;致伤原因多为钝器伤;类型... 目的分析新疆石河子地区成年眼外伤住院患者的临床特征及预后影响因素。方法对2007年1月至2017年12月的1532例(1607眼)成年眼外伤的资料进行回顾性研究。结果眼外伤患者以青年男性、汉族为主;多在夏季户外发生;致伤原因多为钝器伤;类型以挫伤和穿孔伤为主;并发症以外伤性前房积血等多见。与眼外伤视力预后差的相关因素:年龄在38~47岁之间有564例,占36.8%;开放性眼外伤546例,占35.6%;外伤性白内障190例,占12.4%;晶状体脱位48例,占3.1%;玻璃体积血101例,占6.6%;视网膜脱离35例,占2.3%;眼球摘除术后22例,占1.4%。结论新疆石河子地区成年眼外伤住院患者以汉族男性为主,多发生在户外由钝器引起,可分为挫伤和穿孔伤的临床特征。眼外伤致盲率极高,需提供多种方式预防眼外伤的发生。 展开更多
关键词 外伤 成年 因素 影响 视力
Influencing factors and growth state classification of a natural Metasequoia population 预览
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作者 Mu Liu Zhongke Feng +1 位作者 Chenghui Ma Liyan Yang 《林业研究:英文版》 CAS CSCD 2019年第1期337-345,共9页
By analyzing the importance of influencing factors and conducting a comparative study of the effects of different sorting algorithms,a new method is proposed that is suitable for classifying the growth state of a natu... By analyzing the importance of influencing factors and conducting a comparative study of the effects of different sorting algorithms,a new method is proposed that is suitable for classifying the growth state of a natural Metasequoia glyptostroboides Hu and W.C.Cheng population.We studied 2817 M.glyptostroboides trees over 100 years old and analyzed their growth state by measuring 15 factors from stumpage,site condition,and environmental data.The dimensionality of all factors were reduced using the random forest algorithm,and we classified the remaining factors using the following algorithms:random forest,back-propagation(BP)neural networks,and support vector machine(SVM).The applicability of each sorting algorithm was analyzed.When all the d factors are used for classification and modeling,the model’s overall accuracy,kappa coefficient and test accuracy were 85.5%,0.739 and 85.8%,respectively.By reducing the dimensionality of the factors using the random forest algorithm,11 factors most strongly influenced the classifications of the growth state of the Metasequoia population:diameter at breast height,height,crown width,age from stumpage data;longitude,latitude,elevation,slope aspect,gradient and slope position from the site condition data;and the edge of the field from the environmental data.For classifying the Metasequoia population,the random forest algorithm has the highest overall accuracy at 87.2%,which is 3.4 and 2.3%higher than the BP neural networks and SVM algorithms,respectively.The SVM algorithm is superior to the random forest algorithm with respect to classifying the state of mortality.The combination of the random forest and SVM algorithms and their combined information can be used to classify and predict the growth state of this natural M.glyptostroboides population to provide a scientific basis for its effective protection. 展开更多
关键词 METASEQUOIA glyptostroboides GROWTH state RANDOM FOREST Support VECTOR machine(SVM) Influencing factor
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Stress distribution and surrounding rock control of mining near to the overlying coal pillar in the working face 预览
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作者 Rui Gao Bin Yu Xiangbin Meng 《矿业科学技术学报:英文版》 CSCD 2019年第6期881-887,共7页
The occurrence of overlying coal pillar(OCP)exerts a strong effect on the stress and strain distribution of the surrounding rock in the stope.In this paper,the stress distribution characteristics are analyzed via the ... The occurrence of overlying coal pillar(OCP)exerts a strong effect on the stress and strain distribution of the surrounding rock in the stope.In this paper,the stress distribution characteristics are analyzed via the numerical calculation with the account of OCP presence or absence.In addition,this study revealed the joint effect of side pressure relief area of the goaf and stress concentration in OCP on the final stress distribution.Furthermore,the rules of abutment stress distribution affected by three influencing factors,namely horizontal-vertical distances between OCP and working face and buried depth of OCP,are analyzed.The functional model linking the peak stress of surrounding rock with the above influencing factors is developed.The field application of the above results proved that the rib spalling and deformation of a 2.95 m-high and 5.66 m-wide roadway could be efficiently controlled by rationally adjusting working states of the support,and adopting the hydraulic prop coordinated with the p type metal beam and anchor cable to strengthen the surrounding rock of working face and roadway,respectively.The proposed measures are considered appropriate to satisfy the safe operation requirements. 展开更多
关键词 Overlying coal pillar(OCP) Stress distribution Influencing factors Surrounding rock control
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Effect of 3.0T Magnetic resonance SWI and MRS on early diagnosis of Neonatal HIE and Regression analysis of related predictive factors
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作者 Xia Li Wei Zhang +1 位作者 Dan Liu Yi-Wen Zeng 《海南医科大学学报(英文版)》 2019年第1期75-78,共4页
Objective:To investigate the value of 3.0T magnetic resonance imaging (MR) susceptibility weighted imaging (SWI) and magnetic resonance spectrum (MRS) in evaluating the brain injury degree in neonates with hypoxic-isc... Objective:To investigate the value of 3.0T magnetic resonance imaging (MR) susceptibility weighted imaging (SWI) and magnetic resonance spectrum (MRS) in evaluating the brain injury degree in neonates with hypoxic-ischemic encephalopathy (HIE) and the related predictive factors of early diagnosis of HIE.Methods: 60 cases of neonatal HIE diagnosed in our hospital from October 2014 to March 2016 were analyzed statistically. Then the detection rate of SWI and MRS in detecting intracranial hemorrhage foci and the number of injured lobes was compared, the correlation among clinical grading, SWI grading, and MRS grading was also analyzed, thereafter, the predictive factors of early diagnosis of HIE were determined. Results: Among the 60 cases of HIE, the detection rate of SWI and MRS was 91.4% and 100%, respectively. The general data of HIE patients with different injury degrees were statistically different (P<0.05), and there was a significant correlation between clinical grading, SWI grading and MRS grading (P<0.05), while the clinical grading detection had no difference between two methods (P>0.05);For the detection of the number of damaged brain lobes, SWI was better than MRS in mild clinical grading (P<0.05), with no difference in the rest degrees (P>0.05). Multivariate logistic regression analysis showed that meconium stained amniotic fluid, cord entanglement and Apgar score were independent predictors of HIE (P<0.05). Conclusion: 3.0T MR SWI and MRS, as newly developed MRI imaging techniques in recent years, are highly sensitive to intracranial hemorrhage in neonates, which can noninvasively judge the severity of brain injury in HIE newborns from the quantitatively analysis of changes of specific biochemical components and biochemical indicators. 展开更多
关键词 HIE BRAIN INJURY MRI Influencing factors
Spatial Pattern Characteristics and Influencing Factors of National Forest Cities in China 预览
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作者 HAN Jing TANG Beipei HOU Shaojing 《景观研究:英文版》 2019年第5期35-40,共6页
In view of the deficiency of national forest cities in the exploration of spatial pattern and influencing factors,this paper adopted the methods of nearest neighbor analysis,kernel density analysis and unbalanced inde... In view of the deficiency of national forest cities in the exploration of spatial pattern and influencing factors,this paper adopted the methods of nearest neighbor analysis,kernel density analysis and unbalanced index calculation to analyze the spatial agglomeration pattern and spatial differentiation pattern of national forest cities.The factors affecting the selection and distribution of national forest cities were investigated by using the geographic detector and GWR model.The research results show that:① National forest cities show a spatial aggregation pattern of “east and west sparse,gradient change”,whose distribution is closely related to the climatic area;② The number of national garden cities,forest coverage rate,urbanization rate and local general budget income are four factors that have significant influence on the selection and distribution of national forest cities;③ The four significant influencing factors all have different degrees of spatial non-stationarity,and their two-factor and nonlinear enhancement effects can be generated after two interactions,among which the enhancement effect is the most obvious when the local general budget income interacts with other factors. 展开更多
关键词 NATIONAL FOREST CITIES Distribution pattern Influencing factors GeoDetectors GWR model
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Factors Influencing Second Language Learners’Goal Setting 预览
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作者 郭志霞 《海外英语》 2019年第3期20-22,共3页
Goalsetting,as one of the most important meta-cognitive strategies in learning,has gained considerable attention(Bruce,2011).A number of studies have focused on the positive effect of goal setting in sustaining motiva... Goalsetting,as one of the most important meta-cognitive strategies in learning,has gained considerable attention(Bruce,2011).A number of studies have focused on the positive effect of goal setting in sustaining motivation,promoting self-efficacy and fostering autonomy.However,few research seems to examine the factors that influence second language learners’goal setting.The current study aims to address this gap by investigating the goal setting processes of two postgraduate learners at Tianjin Foreign Studies Universities.Interviews were triangulated to obtain a deep understanding.Findings revealed that motivation,self-efficacy,learning strategy,time management can all have influences on the language learners’goal-setting. 展开更多
关键词 GOAL-SETTING influencing FACTORS MOTIVATION SECOND LANGUAGE LEARNER
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Reform of the World Trade Organization:Challenges, Progress, and China’s Position 预览
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作者 Ke Jing 《现代国际关系:英文版》 2019年第4期21-41,共21页
Since the founding of the World Trade Organization(WTO), the high heterogeneity among its members and the difficulty of coordinating those members’ interests, coupled with the guiding principle of consensus decision-... Since the founding of the World Trade Organization(WTO), the high heterogeneity among its members and the difficulty of coordinating those members’ interests, coupled with the guiding principle of consensus decision-making, have repeatedly led WTO negotiations into deadlocks.Recently, the US, increasingly dissatisfied with the distribution of interests in the current international economic system, has been forcing its major trading partners to make concessions more frequently, using unilateral trade policies intended to reshape the global trade order. Thus, WTO reform is becoming even more complicated due to increased competition among great powers. Expanding regionalism is also likely to turn into a tool for geopolitical competition, posing a greater threat to the institutional basis of the multilateral trading system. China should support the multilateral trading system and guide reforms toward justice,inclusiveness, and openness. Furthermore, as it accelerates the pace of its own reform and opening up, China should narrow its divergence of rules with western countries within reasonable scope, ensure that due attention is given to the appeals of developing countries, and defend the goals and principles of the WTO. 展开更多
关键词 WTO REFORM CHALLENGES influencing FACTORS China's POSITIONS
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Application of Anti-leakage Construction Technology in Housing Construction 预览
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作者 Can Chen 《建筑发展研究》 2019年第1期1-4,共4页
With the continuous development and progress of the market economy,the number of building construction projects is increasing.In order to effectively improve the quality of housing construction projects,relevant depar... With the continuous development and progress of the market economy,the number of building construction projects is increasing.In order to effectively improve the quality of housing construction projects,relevant departments must actively promote various quality supervision and management technologies in order to fundamentally improve the construction engineering technology.The monitoring effect to a certain extent achieves the sustainable development goals of the quality of construction projects.This paper combines the case to analyse the factors affecting the operation of anti-leakage construction technology in the construction project,and discusses the application path of technology in the construction of housing construction. 展开更多
关键词 ANTI-LEAKAGE CONSTRUCTION TECHNOLOGY HOUSING CONSTRUCTION influencing FACTORS APPLICATION
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