The mechanical properties of deep-sea sediments during the driving process of crawler collectors are essential factors in the design of mining systems.In this study,a crawler load is divided into a normal compression ...The mechanical properties of deep-sea sediments during the driving process of crawler collectors are essential factors in the design of mining systems.In this study,a crawler load is divided into a normal compression load and a horizontal shear load.Then,the internal stress state of sedimentary soil is examined through a theoretical calculation and finite element numerical simulation.Finally,the driving of crawlers is simulated by changing the relative spatial position between the load and stress unit,obtaining the stress path of the soil unit.Based on the calculation results,the effect of the horizontal shear load on the soil stress response is analyzed at different depths,and the spatial variation law of the soil stress path is examined.The results demonstrate that the horizontal shear load has a significant effect on the rotation of the principal stress,and the reverse rotation of the principal stress axis becomes obvious with the increase in the burial depth.The stress path curve of the soil is different at various depths.The spatial variation rule of the stress path of the shallow soil is complex,whereas the stress path curve of the deep soil tends to shrink as the depth increases.The stress path of the corresponding depth should be selected according to the actual research purpose and applied to the laboratory test.展开更多
Effects of environmental factors such as climate,topography,vegetation and soil in shelter forests in Three Gorges Reservoir Region on runoff and sediment yields were monitored to identify dominant environmental facto...Effects of environmental factors such as climate,topography,vegetation and soil in shelter forests in Three Gorges Reservoir Region on runoff and sediment yields were monitored to identify dominant environmental factors controlling runoff and sediment yields in 15 runoff plots in study area by soil sampling,laboratory analysis,stepwise regression analysis and path analysis,and to establish the main control environmental factors that affect runoff and sediment yields. The results showed that soil bulk density,herbaceous cover,slope,and canopy density were the significant factors controlling runoff,and the direct path coefficient of each factor was ranked as canopy closure(-0. 628) > litter thickness(-0. 547) > bulk density( 0. 509) > altitude( 0. 289). The indirect path coefficient was ranked as soil bulk density( 0. 354) >litter thickness(-0. 169) > altitude( 0. 126) > canopy closure(-0. 104). Therefore,canopy closure and litter thickness mainly had direct effects on runoff,while soil bulk density mainly had indirect effects through their contributions to other factors. Herbaceous cover,litter thickness,slope,canopy density,and altitude were the significant factors controlling sediment yields. The direct path coefficient of each factor was ranked as herbaceous cover(-0. 815) > litter thickness(-0. 777) > canopy closure(-0. 624) > slope( 0. 620). The indirect path coefficient was ranked as slope( 0. 272) > litter thickness(-0. 131) > canopy closure(-0. 097) > herbaceous cover(-0. 084). Therefore,herbaceous cover and litter thickness mainly had direct effects on sediment yields,while slope mainly had indirect effects through their contributions to other factors. All the selected environmental factors jointly explained 85. 5% and 78. 3% of runoff and sediment yield variability,respectively. However,there were large values of remaining path coefficients of other factors influencing runoff and sediment yields,which indicated that some important factors are not included and should be taken into account.展开更多
With the rapid development of science and technology and the increasing popularity of the Internet,the number of network users is gradually expanding,and the behavior of network users is becoming more and more complex...With the rapid development of science and technology and the increasing popularity of the Internet,the number of network users is gradually expanding,and the behavior of network users is becoming more and more complex.Users’actual demand for resources on the network application platform is closely related to their historical behavior records.Therefore,it is very important to analyze the user behavior path conversion rate.Therefore,this paper analyses and studies user behavior path based on sales data.Through analyzing the user quality of the website as well as the user’s repurchase rate,repurchase rate and retention rate in the website,we can get some user habits and use the data to guide the website optimization.展开更多
Improvement of yield in rice(Oryza sativa L.) is vital for ensuring food security in China. Both rice breeders and growers need an improved understanding of the relationship between yield and yield-related traits. New...Improvement of yield in rice(Oryza sativa L.) is vital for ensuring food security in China. Both rice breeders and growers need an improved understanding of the relationship between yield and yield-related traits. New indica cultivars(53 in 2007 and 48 in 2008) were grown in Taoyuan,Yunnan province, to identify important components contributing to yield. Additionally, two standard indica rice cultivars with similar yield potentials, II You 107(a large-panicle type) and Xieyou 107(a heavy-panicle type), were planted in Taoyuan, Yunnan province and Nanjing,Jiangsu province, from 2006 to 2008 to evaluate the stability of yield and yield-related attributes.Growth duration(GD), leaf area index(LAI), panicles per m2(PN), and spikelets per m2(SM) were significantly and positively correlated with grain yield(GY) over all years. Sequential path analysis identified PN and panicle weight(PW) as important first-order traits that influenced grain yield. All direct effects were significant, as indicated by bootstrap analysis. Yield potential varied greatly across locations but not across years. Plant height(PH), days from heading to maturity(HM), and grain weight(GW) were stable traits that showed little variation across sites or years, whereas GD(mainly the pre-heading period, PHP) and PN varied significantly across locations. To achieve a yield of 15 t ha-1, a cultivar should have a PH of 110–125 cm, a long GD with HM of approximately 40 days, a PN of 300–400 m-2, and a GW of 29–31 mg.展开更多
Rational planning of agricultural product transport route from initial node to destination node can effectively reduce the cost price of agricultural products,and the calculation of shortest path between any two point...Rational planning of agricultural product transport route from initial node to destination node can effectively reduce the cost price of agricultural products,and the calculation of shortest path between any two points also affects people’s daily travel.Taking Heze Railway Station to Heze College for example,with remote sensing image data as the base map,we conduct vectorization and topological analysis on roads in the target area.With Dijkstra as theoretical basis of shortest path algorithm,we use ArcG IS network analysis method to build road network,and calculate the planning program of the shortest distance path,the shortest path by driving and the shortest path by walking.展开更多
Spring snowmelt peak flow(SSPF) can cause serious damage. Precipitation as rainfall directly contributes to the SSPF and influences the characteristics of the SSPF, while temperature indirectly impacts the SSPF by sha...Spring snowmelt peak flow(SSPF) can cause serious damage. Precipitation as rainfall directly contributes to the SSPF and influences the characteristics of the SSPF, while temperature indirectly impacts the SSPF by shaping snowmelt rate and determining the soil frozen state which partitions snowmelt water into surface runoff and soil infiltration water in spring. It is necessary to identify the important and significant paths of climatic factors influencing the SSPF and provide estimates of the magnitude and significance of hypothesized causal connections between climatic factors and the SSPF.This study used path analysis with a selection of five factors – the antecedent precipitation index(API),spring precipitation(SP), winter precipitation as snowfall(WS), <0°C temperature accumulation in winter(|ATN|), and average >0°C temperature accumulation in spring(AT) – to analyze their influences on the SSPF in the Kaidu River in Xinjiang,China. The results show that |ATN|, AT and WS have a significant correlation with the SSPF, while API and SP do not show a significant correlation. AT and WS directly influence the SSPF, while as the influence of |ATN| on SSPF is indirect through WS and AT. The indirect influence of |ATN| on SSPF through WS accounts for 69% of the total influence of |ATN| on SSPF. Compared to the multiple linear regression method, path analysis provides additional valuable information, including influencing paths from independent variables to the dependent variable as well as direct and indirect impacts of external variables on the internal variable. This information can help improve the description of snow melt and spring runoff in hydrologic models as well as the planning and management of water resources.展开更多
Using correlation and path analysis, the genetic correlation between weight traits and morphological traits was determined in the marine gastropod Glossaulax reiniana. A total of 100 G. reiniana individuals from a wil...Using correlation and path analysis, the genetic correlation between weight traits and morphological traits was determined in the marine gastropod Glossaulax reiniana. A total of 100 G. reiniana individuals from a wild population were used. Shell width( X 1), shell height( X 2), umbo-callus height( X 3), body width( X 4), operculum length( X 5), operculum width( X 6), body weight( Y 1) and soft-tissue weight( Y 2) were measured, and the correlation coefficient matrix calculated. Morphological traits were used as independent variables and weight traits as dependent variables for path coefficient analysis. Path coefficients, correlation indices and determination coefficients were also determined. Results indicate that the correlation coefficients associated with each morphological and weight trait were all highly significant( P <0.01). After deleting redundant independent variables, the following optimum multiple regression equations were obtained using stepwise multiple regression analysis: Y 1 =- 29.317+0.362 X 2 +0.349 X 4 + 1.190 X 5 for body weight; and Y 2 =- 17.292+0.166 X 1 +0.171 X 2 +0.703 X 5, for soft-tissue weight. Operculum height had the highest positive direct correlation with both body weight and soft-tissue weight, which was in accordance with the test results obtained from determinate coefficient analysis. The indication of high genetic correlations between weight traits and morphological traits will provide valuable information for G. reiniana breeding programs.展开更多
Runoff formation is a complex meteorological-hydrological process impacted by many factors,especially in the inland river basin.Based on the data of daily mean air temperature,precipitation and runoff during the perio...Runoff formation is a complex meteorological-hydrological process impacted by many factors,especially in the inland river basin.Based on the data of daily mean air temperature,precipitation and runoff during the period of 1958-2007 in the Kaidu River watershed,this paper analyzed the changes in air temperature,precipitation and runoff and revealed the direct and indirect impacts of daily air temperature and precipitation on daily runoff by path analysis.The results showed that mean temperature time series of the annual,summer and autumn had a significant fluctuant increase during the last 50 years(P < 0.05).Only winter precipitation increased significantly(P < 0.05) with a rate of 1.337 mm/10a.The annual and winter runoff depthes in the last 50 years significantly increased with the rates of 7.11 mm/10a and 1.85 mm/10a,respectively.The driving function of both daily temperature and precipitation on daily runoff in annual and seasonal levels is significant in the Kaidu River watershed by correlation analysis.The result of path analysis showed that the positive effect of daily air temperature on daily runoff depth is much higher than that of daily precipitation in annual,spring,autumn and winter,however,the trend is opposite in summer.展开更多
Operational transfer path analysis(OTPA)is an advanced vibration and noise transfer path identification and contribution evaluation method.However,the application of OTPA to rail transit vehicles considers only the ex...Operational transfer path analysis(OTPA)is an advanced vibration and noise transfer path identification and contribution evaluation method.However,the application of OTPA to rail transit vehicles considers only the excitation amplitude and ignores the influence of the excitation phase.This study considers the influence of the excitation amplitude and phase,and analyzes the contribution of the secondary suspension path to the floor vibration when the metro vehicle runs at 60 km/h,using an analysis based on the OTPA method.The results show that the vertical direction of the anti-rolling torsion bar area provides the maximum contribution to the floor vibration,with a contribution of 22.1%,followed by the longitudinal vibration of the air spring area,with a contribution of 17.1%.Based on the contribution analysis,a transfer path optimization scheme is proposed,which may provide a reference for the optimization of the transfer path of metro vehicles in the future.展开更多
The present study was carried out to access correlation coefficient, path analysis and genetic variability among twenty one locally developed maize hybrids for ten characters. Positive and significant genotypic, pheno...The present study was carried out to access correlation coefficient, path analysis and genetic variability among twenty one locally developed maize hybrids for ten characters. Positive and significant genotypic, phenotypic correlation coefficient were recorded for yield with anthesis silking interval (rg = 1.00**, rp = 0.96**), cob diameter (rg = 0.99** and rp = 0.95**) and ear height (rg = 0.98** and rp = 0.94**). But days to 50% tasseling had moderate but significant positive correlation at both phenotypic and genotypic level. High genotypic coefficient of variation (GCV) was obtained from thousand seed weight, days to 50% silking, cob diameter and anthesis silking interval. The highest phenotypic coefficient of variation (PCV) was observed in thousand seed weight followed by days to 50% silking and cob diameter. The highest heritability (Hb) was observed for cob diameter (95.25) followed by days to 50% silking (94.15), days to maturity (93.85) and ear height (93.06). The characters with high GCV and higher values of heritability indicated high potential for selection. Anthesis silking interval (0.79) had the highest positive direct effect on yield followed by cob diameter (0.31), cob length (0.31) and plant height (0.04) indicating the effectiveness of direct selection. While some other characters such as days to 50% tasseling (-0.12), days to 50% silking (-1.78), ear height (-1.16), days to maturity (-0.64) exhibited indirect negative effect on yield indicating the effectiveness of indirect selection.展开更多
The problem of farmers' income growth is the key of issues concerning agriculture,countryside and farmers,so the farmers' income growth is the fundamental starting point for agricultural and rural economic dev...The problem of farmers' income growth is the key of issues concerning agriculture,countryside and farmers,so the farmers' income growth is the fundamental starting point for agricultural and rural economic development. In this paper,we use the statistics concerning farmers' income in Yunnan Province from 1995 to 2012,to perform the path analysis of components of farmers' income in Yunnan Province,study the path of influence of components of farmers' income on farmers' net income,and then set forth the policy recommendations for increasing farmers' income in Yunnan Province.展开更多
Hubei Province is one of the critical grain production regions in China with the quantitative cultivated landand good natural condition; it plays an important role in grain security in China. However, owing to rapid e...Hubei Province is one of the critical grain production regions in China with the quantitative cultivated landand good natural condition; it plays an important role in grain security in China. However, owing to rapid economicgrowth, population pressures, anthropogenic activities, and natural disasters, the quality of the cultivated land hassignificantly decreased in recent years and environmental resources are under increasing stress. In order to research onthe mechanism of the change of the cultivated land, this paper analyzes qualitatively the influencing factors of thecultivated land change in Hubei Province from 1978 to 2004, and distinguishes the direct factors from indirect influentones by means of the approach of the path analysis. The result shows that the area of the rent land in the total non-agricultural land, the total population growth and the fixed asset investment are the main factors deciding the change ofthe cultivated land. Meanwhile, the density of the transportation network, the proportion of per capita income of ruralcitizens to that of urban citizens, non-agricultural gross domestic production’s share of the total GDP has a less directeffect but a more indirect influence on the decrease of the cultivated land in Hubei Province. The result means that whilesome factors have less direct influence on the change of the cultivated land, its indirect influence are significant, viceversa. Thus it’s necessary to adopt a comprehensive measurement to protect the cultivated land.展开更多
The targeted poverty alleviation policy isone of the important methods to solve the problemof poverty in China. After the implementation of thetargeted poverty alleviation policy in China, someresults have shown posit...The targeted poverty alleviation policy isone of the important methods to solve the problemof poverty in China. After the implementation of thetargeted poverty alleviation policy in China, someresults have shown positive. However, due to theshortage of resources and talents for poverty alleviation,there are still some shortcomings in the targeted povertyalleviation work. In the process of targeted povertyalleviation, if we can promote social work to participatein targeted poverty alleviation and use a wider rangeof social forces to provide more professional andtargeted assistance work for the poor, we will achievethe final sprint for the success of targeted povertyalleviation in China and a well-off society. Based onthe actual situation of China’s current targeted povertyalleviation work, this article takes the relationship andcontent of rural social work in Sichuan Province aspart of the targeted poverty alleviation as well as thedifficulties it faces. The analysis focuses on the pathof rural social work in Sichuan Province to targetedpoverty alleviation and aims to provide more referencesuggestions for targeted poverty alleviation in China.展开更多
Passengers’demands for riding comfort have been getting higher and higher as the high-speed railway develops.Scientific methods to analyze the interior noise of the high-speed train are needed and the operational tra...Passengers’demands for riding comfort have been getting higher and higher as the high-speed railway develops.Scientific methods to analyze the interior noise of the high-speed train are needed and the operational transfer path analysis(OTPA)method provides a theoretical basis and guidance for the noise control of the train and overcomes the shortcomings of the traditional method,which has high test efficiency and can be carried out during the working state of the targeted machine.The OTPA model is established from the aspects of“path reference point-target point”and“sound source reference point-target point”.As for the mechanism of the noise transmission path,an assumption is made that the direct sound propagation is ignored,and the symmetric sound source and the symmetric path are merged.Using the operational test data and the OTPA method,combined with the results of spherical array sound source identification,the path contribution and sound source contribution of the interior noise are analyzed,respectively,from aspects of the total value and spectrum.The results show that the OTPA conforms to the calculation results of the spherical array sound source identification.At low speed,the contribution of the floor path and the contribution of the bogie sources are dominant.When the speed is greater than 300 km/h,the contribution of the roof path is dominant.Moreover,for the carriage with a pantograph,the lifted pantograph is an obvious source.The noise from the exterior sources of the train transfer into the interior mainly through the form of structural excitation,and the contribution of air excitation is non-significant.Certain analyses of train parts provide guides for the interior noise control.展开更多
In the paper presented, 99 single seed descent barley lines as well as their parental forms Roland and Apex were studied. The grain weight components and their interrelations were analyzed using simple coefficients of...In the paper presented, 99 single seed descent barley lines as well as their parental forms Roland and Apex were studied. The grain weight components and their interrelations were analyzed using simple coefficients of correlation. The direct and indirect effects of such components on grain weight per plant and 1 000-grain weight were estimated using path analysis. In the 2006 and 2007, the spike length and number of spikelets per spike were the determinants of grain weight. Genetic parameters as additive and epistasis effects were estimated for all studied traits. The results indicate the importance of both additive and epistasis gene effects of number of spikes per plant, grain weight per spike, grain number per plant and grain weight per plant in this study.展开更多
Undergraduate student’s satisfaction is fundamental to creating and implementing successful higher education.The present study sought to identify the factors and analyses impact on satisfaction and service quality.Th...Undergraduate student’s satisfaction is fundamental to creating and implementing successful higher education.The present study sought to identify the factors and analyses impact on satisfaction and service quality.The research was carried out in Chinese higher education institution,with a sample of 1660 students.Based on the higher education satisfaction questionnaire,the“optimal path”model of problem improvement was constructed by applying the“structural equation model”,satisfaction and importance matrix diagram,improvement effect size and other tools.Eight major areas of three-dimensional improvement of“satisfaction,importance,and improvement effect”were formed.Identify the issues that students have urgent demands,high importance,and strong improvement effects.Scientifically analyze the main attention focus of each subgroup of students.Concentrate superior resources and strengths,formulate targeted measures and make key breakthroughs based on“light”,“heavy”,“slow”,“urgent”and“classified”.Provide suggestions for improving student’s satisfaction and promoting the development of high-quality connotative and characteristic development in higher education.展开更多
The contents of carbon(C),nitrogen(N),and phosphorus(P)in soil-microorganisms-plant significantly affect tea quality by altering the main quality components of tea,such as tea polyphenols,amino acids,and caffeine.Howev...The contents of carbon(C),nitrogen(N),and phosphorus(P)in soil-microorganisms-plant significantly affect tea quality by altering the main quality components of tea,such as tea polyphenols,amino acids,and caffeine.However,few studies have quantified the effects of these factors on the main quality components of tea.The study aimed to explore the interactions of C,N,and P in soil-microorganisms-plants and the effects of these factors on the main quality components of tea by using the path analysis method.The results indicated that(1)The contents of C,N,and P in soil,microorganisms,and tea plants were highly correlated and collinear,and showed significant correlations with the main quality components of tea.(2)Optimal regression equations were established to esti-mate tea polyphenol,amino acid,catechin,caffeine,and water extract content based on C,N,and P contents in soil,microorganisms,and tea plants(R^(2)=0.923,0.726,0.954,0.848,and 0.883,respectively).(3)Pathway analysis showed that microbial biomass phosphorus(MBP),root phosphorus,branch nitrogen,and microbial biomass carbon(MBC)were the largest direct impact factors on tea polyphenol,catechin,water extracts,amino acid,and caffeine content,respectively.Leaf carbon,root phosphorus,and leaf nitrogen were the largest indirect impact factors on tea polyphenol,catechin,and water extract content,respectively.Leaf carbon indirectly affected tea polyphenol content mainly by altering MBP content.Root phosphorus indirectly affected catechin content mainly by altering soil organic carbon content.Leaf nitrogen indirectly affected water extract content mainly by altering branch nitrogen content.The research results provide the scientific basis for reasonable fertilization in tea gardens and tea quality improvement.展开更多
Kumamoto oysters(Crassostrea sikamea)are important marine aquaculture shellfish because of their taste and round shell shape.Due to its small size,selective breeding is required to improve its market size,but there ar...Kumamoto oysters(Crassostrea sikamea)are important marine aquaculture shellfish because of their taste and round shell shape.Due to its small size,selective breeding is required to improve its market size,but there are no reports on traits suitable for direction selection and reproductive productivity of Kumamoto oysters of different ages.In this study,path analysis and one-way ANOVA were used to explore the influential indices of oyster body weight and fecundity.The results showed that shell height was the main factor affecting the body weight of Kumamoto oysters at one-year-old and two-year-old,followed by shell length.Body weight was the main factor influencing fecundity,and shell height showed a significant correlation with fecundity.Therefore,shell height should be considered the first parameter for selection when selecting Kumamoto oysters for body weight as the direct selection target.When one-year-old and two-year-old Kumamoto oysters were selected as parents from Xiangshan Bay,hatching parameters and growth parameters of F1 generation larvae were measured.The fecundity and egg diameters were 1.72×10^(6)and 46.60±3.62μm,respectively,which were significantly greater than one-aged oysters(5.86×10^(5),40.26±3.52μm).The hatching parameters(fertilized egg size,fertilization rate,and hatching rate)and larval growth performance(D-stage veliger and veliger)were similar and did not differ significantly(P>0.05),and after metamorphosis,there was also no significant difference in shell height size at 40 days of age(P>0.05).Therefore,there was no significant effect of age on reproduction,larval development,and the early growth of Kumamoto oysters.These results could provide a basis for parental sources and proper traits for Kumamoto oyster selection,which is beneficial to developing and utilizing this excellent germplasm resource.展开更多
基金supported by the National Natural Science Foundation of China(Nos.U1906234,51822904,51579082)the Fundamental Research Funds for the Central Universities(No.2020MS027).
文摘The mechanical properties of deep-sea sediments during the driving process of crawler collectors are essential factors in the design of mining systems.In this study,a crawler load is divided into a normal compression load and a horizontal shear load.Then,the internal stress state of sedimentary soil is examined through a theoretical calculation and finite element numerical simulation.Finally,the driving of crawlers is simulated by changing the relative spatial position between the load and stress unit,obtaining the stress path of the soil unit.Based on the calculation results,the effect of the horizontal shear load on the soil stress response is analyzed at different depths,and the spatial variation law of the soil stress path is examined.The results demonstrate that the horizontal shear load has a significant effect on the rotation of the principal stress,and the reverse rotation of the principal stress axis becomes obvious with the increase in the burial depth.The stress path curve of the soil is different at various depths.The spatial variation rule of the stress path of the shallow soil is complex,whereas the stress path curve of the deep soil tends to shrink as the depth increases.The stress path of the corresponding depth should be selected according to the actual research purpose and applied to the laboratory test.
基金Supported by National Key Technology Research and Development Program of the Ministry of Science and Technology of China(2015BAD07B04)Key Science and Technology Program of Henan Province,China(152102110059)
文摘Effects of environmental factors such as climate,topography,vegetation and soil in shelter forests in Three Gorges Reservoir Region on runoff and sediment yields were monitored to identify dominant environmental factors controlling runoff and sediment yields in 15 runoff plots in study area by soil sampling,laboratory analysis,stepwise regression analysis and path analysis,and to establish the main control environmental factors that affect runoff and sediment yields. The results showed that soil bulk density,herbaceous cover,slope,and canopy density were the significant factors controlling runoff,and the direct path coefficient of each factor was ranked as canopy closure(-0. 628) > litter thickness(-0. 547) > bulk density( 0. 509) > altitude( 0. 289). The indirect path coefficient was ranked as soil bulk density( 0. 354) >litter thickness(-0. 169) > altitude( 0. 126) > canopy closure(-0. 104). Therefore,canopy closure and litter thickness mainly had direct effects on runoff,while soil bulk density mainly had indirect effects through their contributions to other factors. Herbaceous cover,litter thickness,slope,canopy density,and altitude were the significant factors controlling sediment yields. The direct path coefficient of each factor was ranked as herbaceous cover(-0. 815) > litter thickness(-0. 777) > canopy closure(-0. 624) > slope( 0. 620). The indirect path coefficient was ranked as slope( 0. 272) > litter thickness(-0. 131) > canopy closure(-0. 097) > herbaceous cover(-0. 084). Therefore,herbaceous cover and litter thickness mainly had direct effects on sediment yields,while slope mainly had indirect effects through their contributions to other factors. All the selected environmental factors jointly explained 85. 5% and 78. 3% of runoff and sediment yield variability,respectively. However,there were large values of remaining path coefficients of other factors influencing runoff and sediment yields,which indicated that some important factors are not included and should be taken into account.
基金funded by the Open Foundation for the University Innovation Platform in the Hunan Province,grant number 18K103Open project,Grant Number 20181901CRP03,20181901CRP04,20181901CRP05+1 种基金Hunan Provincial Education Science 13th Five-Year Plan(Grant No.XJK016BXX001),Social Science Foundation of Hunan Province(Grant No.17YBA049)supported by the project 18K103。
文摘With the rapid development of science and technology and the increasing popularity of the Internet,the number of network users is gradually expanding,and the behavior of network users is becoming more and more complex.Users’actual demand for resources on the network application platform is closely related to their historical behavior records.Therefore,it is very important to analyze the user behavior path conversion rate.Therefore,this paper analyses and studies user behavior path based on sales data.Through analyzing the user quality of the website as well as the user’s repurchase rate,repurchase rate and retention rate in the website,we can get some user habits and use the data to guide the website optimization.
基金supported by the National Key Technology R&D Program of China (2011BAD16B14, 2012BAD20B05, 2012BAD04B08, and 2013BAD20B05)
文摘Improvement of yield in rice(Oryza sativa L.) is vital for ensuring food security in China. Both rice breeders and growers need an improved understanding of the relationship between yield and yield-related traits. New indica cultivars(53 in 2007 and 48 in 2008) were grown in Taoyuan,Yunnan province, to identify important components contributing to yield. Additionally, two standard indica rice cultivars with similar yield potentials, II You 107(a large-panicle type) and Xieyou 107(a heavy-panicle type), were planted in Taoyuan, Yunnan province and Nanjing,Jiangsu province, from 2006 to 2008 to evaluate the stability of yield and yield-related attributes.Growth duration(GD), leaf area index(LAI), panicles per m2(PN), and spikelets per m2(SM) were significantly and positively correlated with grain yield(GY) over all years. Sequential path analysis identified PN and panicle weight(PW) as important first-order traits that influenced grain yield. All direct effects were significant, as indicated by bootstrap analysis. Yield potential varied greatly across locations but not across years. Plant height(PH), days from heading to maturity(HM), and grain weight(GW) were stable traits that showed little variation across sites or years, whereas GD(mainly the pre-heading period, PHP) and PN varied significantly across locations. To achieve a yield of 15 t ha-1, a cultivar should have a PH of 110–125 cm, a long GD with HM of approximately 40 days, a PN of 300–400 m-2, and a GW of 29–31 mg.
基金Supported by Science Foundation of Heze University(XY14SK14)
文摘Rational planning of agricultural product transport route from initial node to destination node can effectively reduce the cost price of agricultural products,and the calculation of shortest path between any two points also affects people’s daily travel.Taking Heze Railway Station to Heze College for example,with remote sensing image data as the base map,we conduct vectorization and topological analysis on roads in the target area.With Dijkstra as theoretical basis of shortest path algorithm,we use ArcG IS network analysis method to build road network,and calculate the planning program of the shortest distance path,the shortest path by driving and the shortest path by walking.
基金financially supported by the Project of State Key Basic R & D Program of China (973 Program, Grant No. 2010CB951002)the key deployment project of Chinese Academy of Sciences (Grant No. KZZD-EW-12-2)Chinese Academy of Sciences Visiting Professorship for Senior International Scientists (Grant No. 2011T2Z40)
文摘Spring snowmelt peak flow(SSPF) can cause serious damage. Precipitation as rainfall directly contributes to the SSPF and influences the characteristics of the SSPF, while temperature indirectly impacts the SSPF by shaping snowmelt rate and determining the soil frozen state which partitions snowmelt water into surface runoff and soil infiltration water in spring. It is necessary to identify the important and significant paths of climatic factors influencing the SSPF and provide estimates of the magnitude and significance of hypothesized causal connections between climatic factors and the SSPF.This study used path analysis with a selection of five factors – the antecedent precipitation index(API),spring precipitation(SP), winter precipitation as snowfall(WS), <0°C temperature accumulation in winter(|ATN|), and average >0°C temperature accumulation in spring(AT) – to analyze their influences on the SSPF in the Kaidu River in Xinjiang,China. The results show that |ATN|, AT and WS have a significant correlation with the SSPF, while API and SP do not show a significant correlation. AT and WS directly influence the SSPF, while as the influence of |ATN| on SSPF is indirect through WS and AT. The indirect influence of |ATN| on SSPF through WS accounts for 69% of the total influence of |ATN| on SSPF. Compared to the multiple linear regression method, path analysis provides additional valuable information, including influencing paths from independent variables to the dependent variable as well as direct and indirect impacts of external variables on the internal variable. This information can help improve the description of snow melt and spring runoff in hydrologic models as well as the planning and management of water resources.
基金Supported by the Modern Agro-Industry Technology Research System(No.CARS-48)
文摘Using correlation and path analysis, the genetic correlation between weight traits and morphological traits was determined in the marine gastropod Glossaulax reiniana. A total of 100 G. reiniana individuals from a wild population were used. Shell width( X 1), shell height( X 2), umbo-callus height( X 3), body width( X 4), operculum length( X 5), operculum width( X 6), body weight( Y 1) and soft-tissue weight( Y 2) were measured, and the correlation coefficient matrix calculated. Morphological traits were used as independent variables and weight traits as dependent variables for path coefficient analysis. Path coefficients, correlation indices and determination coefficients were also determined. Results indicate that the correlation coefficients associated with each morphological and weight trait were all highly significant( P <0.01). After deleting redundant independent variables, the following optimum multiple regression equations were obtained using stepwise multiple regression analysis: Y 1 =- 29.317+0.362 X 2 +0.349 X 4 + 1.190 X 5 for body weight; and Y 2 =- 17.292+0.166 X 1 +0.171 X 2 +0.703 X 5, for soft-tissue weight. Operculum height had the highest positive direct correlation with both body weight and soft-tissue weight, which was in accordance with the test results obtained from determinate coefficient analysis. The indication of high genetic correlations between weight traits and morphological traits will provide valuable information for G. reiniana breeding programs.
基金supported by the National Natural Sciences Foundation of China (40871027)the Initial Project of State Key Basic R & D Program of China (2009CB426309)the Knowledge Innovation Project of Chinese Academy of Sciences (KZCX2-YW-334)
文摘Runoff formation is a complex meteorological-hydrological process impacted by many factors,especially in the inland river basin.Based on the data of daily mean air temperature,precipitation and runoff during the period of 1958-2007 in the Kaidu River watershed,this paper analyzed the changes in air temperature,precipitation and runoff and revealed the direct and indirect impacts of daily air temperature and precipitation on daily runoff by path analysis.The results showed that mean temperature time series of the annual,summer and autumn had a significant fluctuant increase during the last 50 years(P < 0.05).Only winter precipitation increased significantly(P < 0.05) with a rate of 1.337 mm/10a.The annual and winter runoff depthes in the last 50 years significantly increased with the rates of 7.11 mm/10a and 1.85 mm/10a,respectively.The driving function of both daily temperature and precipitation on daily runoff in annual and seasonal levels is significant in the Kaidu River watershed by correlation analysis.The result of path analysis showed that the positive effect of daily air temperature on daily runoff depth is much higher than that of daily precipitation in annual,spring,autumn and winter,however,the trend is opposite in summer.
基金Supported by National Natural Science Foundation of China(Grant Nos.U1934203,U1734201)Sichuan Science and Technology Program(Grant No.2020YJ0254)Fundamental Research Funds for the State Key Laboratory of Traction Power(Grant No.2019-Q02).
文摘Operational transfer path analysis(OTPA)is an advanced vibration and noise transfer path identification and contribution evaluation method.However,the application of OTPA to rail transit vehicles considers only the excitation amplitude and ignores the influence of the excitation phase.This study considers the influence of the excitation amplitude and phase,and analyzes the contribution of the secondary suspension path to the floor vibration when the metro vehicle runs at 60 km/h,using an analysis based on the OTPA method.The results show that the vertical direction of the anti-rolling torsion bar area provides the maximum contribution to the floor vibration,with a contribution of 22.1%,followed by the longitudinal vibration of the air spring area,with a contribution of 17.1%.Based on the contribution analysis,a transfer path optimization scheme is proposed,which may provide a reference for the optimization of the transfer path of metro vehicles in the future.
文摘The present study was carried out to access correlation coefficient, path analysis and genetic variability among twenty one locally developed maize hybrids for ten characters. Positive and significant genotypic, phenotypic correlation coefficient were recorded for yield with anthesis silking interval (rg = 1.00**, rp = 0.96**), cob diameter (rg = 0.99** and rp = 0.95**) and ear height (rg = 0.98** and rp = 0.94**). But days to 50% tasseling had moderate but significant positive correlation at both phenotypic and genotypic level. High genotypic coefficient of variation (GCV) was obtained from thousand seed weight, days to 50% silking, cob diameter and anthesis silking interval. The highest phenotypic coefficient of variation (PCV) was observed in thousand seed weight followed by days to 50% silking and cob diameter. The highest heritability (Hb) was observed for cob diameter (95.25) followed by days to 50% silking (94.15), days to maturity (93.85) and ear height (93.06). The characters with high GCV and higher values of heritability indicated high potential for selection. Anthesis silking interval (0.79) had the highest positive direct effect on yield followed by cob diameter (0.31), cob length (0.31) and plant height (0.04) indicating the effectiveness of direct selection. While some other characters such as days to 50% tasseling (-0.12), days to 50% silking (-1.78), ear height (-1.16), days to maturity (-0.64) exhibited indirect negative effect on yield indicating the effectiveness of indirect selection.
文摘The problem of farmers' income growth is the key of issues concerning agriculture,countryside and farmers,so the farmers' income growth is the fundamental starting point for agricultural and rural economic development. In this paper,we use the statistics concerning farmers' income in Yunnan Province from 1995 to 2012,to perform the path analysis of components of farmers' income in Yunnan Province,study the path of influence of components of farmers' income on farmers' net income,and then set forth the policy recommendations for increasing farmers' income in Yunnan Province.
基金This paper is supported by National Natural Science Foundation of China （Grant No. 40541001 ）Major Program of National Natural Science Foundation of China （Grant No. 40535024）Beijing Municipal Natural Science Foundation （Grant No. 8062020）.
文摘Hubei Province is one of the critical grain production regions in China with the quantitative cultivated landand good natural condition; it plays an important role in grain security in China. However, owing to rapid economicgrowth, population pressures, anthropogenic activities, and natural disasters, the quality of the cultivated land hassignificantly decreased in recent years and environmental resources are under increasing stress. In order to research onthe mechanism of the change of the cultivated land, this paper analyzes qualitatively the influencing factors of thecultivated land change in Hubei Province from 1978 to 2004, and distinguishes the direct factors from indirect influentones by means of the approach of the path analysis. The result shows that the area of the rent land in the total non-agricultural land, the total population growth and the fixed asset investment are the main factors deciding the change ofthe cultivated land. Meanwhile, the density of the transportation network, the proportion of per capita income of ruralcitizens to that of urban citizens, non-agricultural gross domestic production’s share of the total GDP has a less directeffect but a more indirect influence on the decrease of the cultivated land in Hubei Province. The result means that whilesome factors have less direct influence on the change of the cultivated land, its indirect influence are significant, viceversa. Thus it’s necessary to adopt a comprehensive measurement to protect the cultivated land.
基金2019 Sichuan Rural Community Governance Research Center(SQZL2019C04)2019 Sichuan New Rural Culture Construction Research Center(SCXN2019-011)+1 种基金2019 Sichuan Research Center for Application and Development of Educational Informatization(JYXX19-020)2019 Center for Early Childhood Education Research,Sichuan(CECER-2019-C03).
文摘The targeted poverty alleviation policy isone of the important methods to solve the problemof poverty in China. After the implementation of thetargeted poverty alleviation policy in China, someresults have shown positive. However, due to theshortage of resources and talents for poverty alleviation,there are still some shortcomings in the targeted povertyalleviation work. In the process of targeted povertyalleviation, if we can promote social work to participatein targeted poverty alleviation and use a wider rangeof social forces to provide more professional andtargeted assistance work for the poor, we will achievethe final sprint for the success of targeted povertyalleviation in China and a well-off society. Based onthe actual situation of China’s current targeted povertyalleviation work, this article takes the relationship andcontent of rural social work in Sichuan Province aspart of the targeted poverty alleviation as well as thedifficulties it faces. The analysis focuses on the pathof rural social work in Sichuan Province to targetedpoverty alleviation and aims to provide more referencesuggestions for targeted poverty alleviation in China.
文摘Passengers’demands for riding comfort have been getting higher and higher as the high-speed railway develops.Scientific methods to analyze the interior noise of the high-speed train are needed and the operational transfer path analysis(OTPA)method provides a theoretical basis and guidance for the noise control of the train and overcomes the shortcomings of the traditional method,which has high test efficiency and can be carried out during the working state of the targeted machine.The OTPA model is established from the aspects of“path reference point-target point”and“sound source reference point-target point”.As for the mechanism of the noise transmission path,an assumption is made that the direct sound propagation is ignored,and the symmetric sound source and the symmetric path are merged.Using the operational test data and the OTPA method,combined with the results of spherical array sound source identification,the path contribution and sound source contribution of the interior noise are analyzed,respectively,from aspects of the total value and spectrum.The results show that the OTPA conforms to the calculation results of the spherical array sound source identification.At low speed,the contribution of the floor path and the contribution of the bogie sources are dominant.When the speed is greater than 300 km/h,the contribution of the roof path is dominant.Moreover,for the carriage with a pantograph,the lifted pantograph is an obvious source.The noise from the exterior sources of the train transfer into the interior mainly through the form of structural excitation,and the contribution of air excitation is non-significant.Certain analyses of train parts provide guides for the interior noise control.
文摘In the paper presented, 99 single seed descent barley lines as well as their parental forms Roland and Apex were studied. The grain weight components and their interrelations were analyzed using simple coefficients of correlation. The direct and indirect effects of such components on grain weight per plant and 1 000-grain weight were estimated using path analysis. In the 2006 and 2007, the spike length and number of spikelets per spike were the determinants of grain weight. Genetic parameters as additive and epistasis effects were estimated for all studied traits. The results indicate the importance of both additive and epistasis gene effects of number of spikes per plant, grain weight per spike, grain number per plant and grain weight per plant in this study.
基金supported by the Chongqing Education Science Planning funds,and the project is 2021-GX-114.
文摘Undergraduate student’s satisfaction is fundamental to creating and implementing successful higher education.The present study sought to identify the factors and analyses impact on satisfaction and service quality.The research was carried out in Chinese higher education institution,with a sample of 1660 students.Based on the higher education satisfaction questionnaire,the“optimal path”model of problem improvement was constructed by applying the“structural equation model”,satisfaction and importance matrix diagram,improvement effect size and other tools.Eight major areas of three-dimensional improvement of“satisfaction,importance,and improvement effect”were formed.Identify the issues that students have urgent demands,high importance,and strong improvement effects.Scientifically analyze the main attention focus of each subgroup of students.Concentrate superior resources and strengths,formulate targeted measures and make key breakthroughs based on“light”,“heavy”,“slow”,“urgent”and“classified”.Provide suggestions for improving student’s satisfaction and promoting the development of high-quality connotative and characteristic development in higher education.
基金This work was supported by Guizhou Provincial Basic Research Program(Natural Science),Grant Number Qiankehejichu-ZK[2021]YB133Guizhou Provincial Scientific and Technological Program,Grant Number Qiankehehoubuzhu[2020]3001National Natural Science Foundation of China-Guizhou Provincial People’s Government Karst Science Research Centre(U1612442).
文摘The contents of carbon(C),nitrogen(N),and phosphorus(P)in soil-microorganisms-plant significantly affect tea quality by altering the main quality components of tea,such as tea polyphenols,amino acids,and caffeine.However,few studies have quantified the effects of these factors on the main quality components of tea.The study aimed to explore the interactions of C,N,and P in soil-microorganisms-plants and the effects of these factors on the main quality components of tea by using the path analysis method.The results indicated that(1)The contents of C,N,and P in soil,microorganisms,and tea plants were highly correlated and collinear,and showed significant correlations with the main quality components of tea.(2)Optimal regression equations were established to esti-mate tea polyphenol,amino acid,catechin,caffeine,and water extract content based on C,N,and P contents in soil,microorganisms,and tea plants(R^(2)=0.923,0.726,0.954,0.848,and 0.883,respectively).(3)Pathway analysis showed that microbial biomass phosphorus(MBP),root phosphorus,branch nitrogen,and microbial biomass carbon(MBC)were the largest direct impact factors on tea polyphenol,catechin,water extracts,amino acid,and caffeine content,respectively.Leaf carbon,root phosphorus,and leaf nitrogen were the largest indirect impact factors on tea polyphenol,catechin,and water extract content,respectively.Leaf carbon indirectly affected tea polyphenol content mainly by altering MBP content.Root phosphorus indirectly affected catechin content mainly by altering soil organic carbon content.Leaf nitrogen indirectly affected water extract content mainly by altering branch nitrogen content.The research results provide the scientific basis for reasonable fertilization in tea gardens and tea quality improvement.
基金supported by grants from the“3315”Innovative Team of Ningbo City,the Science and Technology Planning Project of Ningbo City(2021S009).
文摘Kumamoto oysters(Crassostrea sikamea)are important marine aquaculture shellfish because of their taste and round shell shape.Due to its small size,selective breeding is required to improve its market size,but there are no reports on traits suitable for direction selection and reproductive productivity of Kumamoto oysters of different ages.In this study,path analysis and one-way ANOVA were used to explore the influential indices of oyster body weight and fecundity.The results showed that shell height was the main factor affecting the body weight of Kumamoto oysters at one-year-old and two-year-old,followed by shell length.Body weight was the main factor influencing fecundity,and shell height showed a significant correlation with fecundity.Therefore,shell height should be considered the first parameter for selection when selecting Kumamoto oysters for body weight as the direct selection target.When one-year-old and two-year-old Kumamoto oysters were selected as parents from Xiangshan Bay,hatching parameters and growth parameters of F1 generation larvae were measured.The fecundity and egg diameters were 1.72×10^(6)and 46.60±3.62μm,respectively,which were significantly greater than one-aged oysters(5.86×10^(5),40.26±3.52μm).The hatching parameters(fertilized egg size,fertilization rate,and hatching rate)and larval growth performance(D-stage veliger and veliger)were similar and did not differ significantly(P>0.05),and after metamorphosis,there was also no significant difference in shell height size at 40 days of age(P>0.05).Therefore,there was no significant effect of age on reproduction,larval development,and the early growth of Kumamoto oysters.These results could provide a basis for parental sources and proper traits for Kumamoto oyster selection,which is beneficial to developing and utilizing this excellent germplasm resource.
