To investigate the impact of temporary structures on the mechanical behavior of shaped bridge towers during the construction process,the Dianbu River Special Bridge was selected as the engineering background.A finite ...To investigate the impact of temporary structures on the mechanical behavior of shaped bridge towers during the construction process,the Dianbu River Special Bridge was selected as the engineering background.A finite element model of the middle tower column during the construction stage was established using ABAQUS to analyze the effects of key parameters,including the angle and pretension of temporary cables,as well as the wall thickness and diameter of temporary diagonal braces.The study examines how these parameters influence the stresses at the towergirder consolidation.The results indicate that the angle of temporary cables significantly affects the tensile stresses at the tower-girder consolidation,while its impact on compressive stresses is minimal.Among all parameters,the pretension of temporary cables has the most pronounced effect on the stresses at the tower-girder consolidation.In contrast,the wall thickness of temporary diagonal braces has only a minor influence,whereas the diameter of temporary diagonal braces has an almost negligible impact.These findings provide valuable insights for optimizing the design and arrangement of temporary support structures in similar bridge construction projects.展开更多
The function of Green Technology Innovation (GTI) in the Eco-Industrial Management (ELM) appears more and more important, but the research on how much this function plays is scarce. The influence of Green Technolo...The function of Green Technology Innovation (GTI) in the Eco-Industrial Management (ELM) appears more and more important, but the research on how much this function plays is scarce. The influence of Green Technology Innovation to the Eco-Industrial Management has gradually received the academic and the industrial attention. In this article an empirical research was attempted to inspect whether such influence exists and to what value. The study attempts to empirically explore the influencing degree of GTI on EIM in China based on the double logarithmic regression equation.展开更多
Based on the previous research,a total of 10 risk indices are selected according to the specific situation in Sichuan Province,such as natural risk,resource constraint risk,internal management risk,capital risk,techni...Based on the previous research,a total of 10 risk indices are selected according to the specific situation in Sichuan Province,such as natural risk,resource constraint risk,internal management risk,capital risk,technical input and output risk,market risk,contract credit risk,property risk and policy support risk.According to the questionnaire survey by cooperative economic organization of Sichuan Province,principal component analysis is used to analyze the importance and influence degree of the operation risk of rural cooperative economic organization.Result shows that in the operation of cooperative economic organization,management risk has greater influence degree and importance degree,which should be paid special attention to.Capital,property,price fluctuation,and quality of members have great degree of risk and are paid little attention to.The technical input and output risk and the contract credit risk have relatively low impact on the operation risk of cooperative economic organization and their importance is relatively low.Therefore,we should continue to maintain its advantages.Nature,resource constraint and policy support have relatively high risk awareness and low influence degree,belonging to the factors with priority attention which are controlled to some extent.Finally,suggestions are put forward,such as enhancing the management level of cooperative economic organizations,strengthening the farmer's risk awareness,and improving the risk aversion ability of cooperative economic organization.展开更多
An importance analysis model for computer numerical control(CNC)lathe subsystems was proposed.The model was based on technique for order preference by similarity to an ideal solution(TOPSIS)and considered the stru...An importance analysis model for computer numerical control(CNC)lathe subsystems was proposed.The model was based on technique for order preference by similarity to an ideal solution(TOPSIS)and considered the structure correlation between subsystems and the complete machine,the fault correlation of each subsystem and so on.The model can obtain a comprehensive sequencing of subsystems based on their importance to the complete machine.It lays a theoretical foundation for reliability allocation.展开更多
In order to analyze the deformation and stress characteristics of the pile foundation on the slope<span><span><span style="font-family:" capt",serif;"="" pro="" m...In order to analyze the deformation and stress characteristics of the pile foundation on the slope<span><span><span style="font-family:" capt",serif;"="" pro="" minion="">, </span></span></span><span><span><span style="font-family:" capt",serif;"="" pro="" minion="">this paper uses the finite element software Abaqus for numerical simulation.</span></span></span><span><span><span style="font-family:" capt",serif;"="" pro="" minion=""> </span></span></span><span><span><span style="font-family:" capt",serif;"="" pro="" minion="">The displacement and stress data of pile under different working conditions (the combination of heap load and vertical load and horizontal load and inclined load) were collected</span></span></span><span><span><span style="font-family:" capt",serif;"="" pro="" minion="">;</span></span></span><span><span><span style="font-family:" capt",serif;"="" pro="" minion="">the distribution of pile displacement, axial force and bending moment were analyzed. Simulation results show that: slope top loading has little effect on vertical displacement</span></span></span><span><span><span style="font-family:" capt",serif;"="" pro="" minion="">;</span></span></span><span><span><span style="font-family:" capt",serif;"="" pro="" minion=""> when the heap load exceeds 200 kPa, the horizontal displacement is greatly affected. Pile axial force decreases with pile burial depth</span></span></span><span><span><span style="font-family:" capt",serif;"="" pro="" minion="">;</span></span></span><span><span><span style="font-family:" capt",serif;"="" pro="" minion="">pile lateral resistance plays a more adequate role in the rock and soil layer. The bending moment of double pile foundation is positive at the top and negative at the bottom.</span></span></span><span><span><span style="font-family:" capt",serif;"="" pro="" minion=""> </span></span></span><span><span><span style="font-family:" capt",serif;"="" pro="" minion="">Applied oblique load has obvious p-Δ effect.</span></span></span>展开更多
In this paper,a physical model of coal roadway which is clamped by upper and lower softrock with extra thickness was built according to the characteristics of soft rock strata in china's western mining area.Then,a...In this paper,a physical model of coal roadway which is clamped by upper and lower softrock with extra thickness was built according to the characteristics of soft rock strata in china's western mining area.Then,a series of orthogonal numerical experiments were carried out by selecting the strength and stiffness parameters of soft rock and coal seam as well as the in situ stress of soft rock strata as experimental factors and roadway displacements(convergence displacements of sides,displacement of roof to floor)as experimental indexes.By constructing the F statistics with different inspection levels,evaluation method for influence of the experimental factors on stability indexes were defined.Thus,influence degrees of specified parameters on the stability of roadway were divided into five classes as follows:highly significant influence,significant influence,relatively significant influence,little significant influence,and no influence respectively which realize the quantitative analysis of the influence degrees of experimental factors.The finite element calculation results showed that main failure mode of coal roadway that usually showed as tension failure of coal seam in roof and deformation factors of coal seam had the most remarkable effect on roadway displacements.The conclusions provide theoretical basis for further analysis of the mechanism of"roof burst"in roadway maintenance.展开更多
In-network caching is one of the most important issues in content centric networking (CCN), which may extremely influence the performance of the caching system. Although much work has been done for in-network cachin...In-network caching is one of the most important issues in content centric networking (CCN), which may extremely influence the performance of the caching system. Although much work has been done for in-network caching scheme design in CCN, most of them have not addressed the multiple network attribute parameters jointly during caching algorithm design. Hence, to fill this gap, a new in-network caching based on grey relational analysis (GRA) is proposed. The authors firstly define two newly metric parameters named request influence degree (RID) and cache replacement rate, respectively. The RID indicates the importance of one node along the content delivery path from the view of the interest packets arriving The cache replacement rate is used to denote the caching load of the node. Then combining hops a request traveling from the users and the node traffic, four network attribute parameters are considered during the in-network caching algorithm design. Based on these four network parameters, a GRA based in-network caching algorithm is proposed, which can significantly improve the performance of CCN. Finally, extensive simulation based on ndnSIM is demonstrated that the GRA-based caching scheme can achieve the lower load in the source server and the less average hops than the existing the betweeness (Betw) scheme and the ALWAYS scheme.展开更多
In previous studies the value of ecosystem services was evaluated microscopically by ecological indicators such as soil properties,biomass,carbon storage,oxygen release,water quality,and others.In this paper,the spati...In previous studies the value of ecosystem services was evaluated microscopically by ecological indicators such as soil properties,biomass,carbon storage,oxygen release,water quality,and others.In this paper,the spatial heterogeneity of ecosystem services in Liuyang River basin was studied from the perspective of Geographic Information System(GIS)based spatial relationships by using a combination of geographic data and spatial analysis technologies.The Liuyang River basin was divided into grids with a resolution of 1km×1km.The weights of factors that affect the value of ecosystem services(such as topography,geological disasters,roads,scenic spots,vegetation coverage,and plant net primary productivity)were evaluated using the entropy method and analytic hierarchy process(AHP)in order to investigate the influence of natural and social factors on the value of ecosystem services in a quantitative manner.The results demonstrate that the value of ecosystem services is mainly affected by vegetation coverage,plant net primary productivity,and road network density.The value of ecosystem services grows with the increase in either vegetation coverage,plant net primary productivity,or road network density.Different types of land play different roles in ecosystem services.Cultivated land,grassland,and water each have significant supply and regulating functions while forest has significant regulating and supporting functions.The value of ecosystem services of cultivated land and water that are closely related to human activity is significantly influenced by spatial heterogeneity.In contrast,the effect of spatial heterogeneity on the value of ecosystem services of forest land and grassland that are located in mountains and hills,far away from the human accumulation zone,is insignificant.展开更多
文摘To investigate the impact of temporary structures on the mechanical behavior of shaped bridge towers during the construction process,the Dianbu River Special Bridge was selected as the engineering background.A finite element model of the middle tower column during the construction stage was established using ABAQUS to analyze the effects of key parameters,including the angle and pretension of temporary cables,as well as the wall thickness and diameter of temporary diagonal braces.The study examines how these parameters influence the stresses at the towergirder consolidation.The results indicate that the angle of temporary cables significantly affects the tensile stresses at the tower-girder consolidation,while its impact on compressive stresses is minimal.Among all parameters,the pretension of temporary cables has the most pronounced effect on the stresses at the tower-girder consolidation.In contrast,the wall thickness of temporary diagonal braces has only a minor influence,whereas the diameter of temporary diagonal braces has an almost negligible impact.These findings provide valuable insights for optimizing the design and arrangement of temporary support structures in similar bridge construction projects.
文摘The function of Green Technology Innovation (GTI) in the Eco-Industrial Management (ELM) appears more and more important, but the research on how much this function plays is scarce. The influence of Green Technology Innovation to the Eco-Industrial Management has gradually received the academic and the industrial attention. In this article an empirical research was attempted to inspect whether such influence exists and to what value. The study attempts to empirically explore the influencing degree of GTI on EIM in China based on the double logarithmic regression equation.
基金Supported by the Subject of Sichuan Center for Rural Development Research(CR0713)
文摘Based on the previous research,a total of 10 risk indices are selected according to the specific situation in Sichuan Province,such as natural risk,resource constraint risk,internal management risk,capital risk,technical input and output risk,market risk,contract credit risk,property risk and policy support risk.According to the questionnaire survey by cooperative economic organization of Sichuan Province,principal component analysis is used to analyze the importance and influence degree of the operation risk of rural cooperative economic organization.Result shows that in the operation of cooperative economic organization,management risk has greater influence degree and importance degree,which should be paid special attention to.Capital,property,price fluctuation,and quality of members have great degree of risk and are paid little attention to.The technical input and output risk and the contract credit risk have relatively low impact on the operation risk of cooperative economic organization and their importance is relatively low.Therefore,we should continue to maintain its advantages.Nature,resource constraint and policy support have relatively high risk awareness and low influence degree,belonging to the factors with priority attention which are controlled to some extent.Finally,suggestions are put forward,such as enhancing the management level of cooperative economic organizations,strengthening the farmer's risk awareness,and improving the risk aversion ability of cooperative economic organization.
基金Supported by the Project of Jilin Province(20150101025JC)the National Natural Science Foundation of China(51175222)
文摘An importance analysis model for computer numerical control(CNC)lathe subsystems was proposed.The model was based on technique for order preference by similarity to an ideal solution(TOPSIS)and considered the structure correlation between subsystems and the complete machine,the fault correlation of each subsystem and so on.The model can obtain a comprehensive sequencing of subsystems based on their importance to the complete machine.It lays a theoretical foundation for reliability allocation.
文摘In order to analyze the deformation and stress characteristics of the pile foundation on the slope<span><span><span style="font-family:" capt",serif;"="" pro="" minion="">, </span></span></span><span><span><span style="font-family:" capt",serif;"="" pro="" minion="">this paper uses the finite element software Abaqus for numerical simulation.</span></span></span><span><span><span style="font-family:" capt",serif;"="" pro="" minion=""> </span></span></span><span><span><span style="font-family:" capt",serif;"="" pro="" minion="">The displacement and stress data of pile under different working conditions (the combination of heap load and vertical load and horizontal load and inclined load) were collected</span></span></span><span><span><span style="font-family:" capt",serif;"="" pro="" minion="">;</span></span></span><span><span><span style="font-family:" capt",serif;"="" pro="" minion="">the distribution of pile displacement, axial force and bending moment were analyzed. Simulation results show that: slope top loading has little effect on vertical displacement</span></span></span><span><span><span style="font-family:" capt",serif;"="" pro="" minion="">;</span></span></span><span><span><span style="font-family:" capt",serif;"="" pro="" minion=""> when the heap load exceeds 200 kPa, the horizontal displacement is greatly affected. Pile axial force decreases with pile burial depth</span></span></span><span><span><span style="font-family:" capt",serif;"="" pro="" minion="">;</span></span></span><span><span><span style="font-family:" capt",serif;"="" pro="" minion="">pile lateral resistance plays a more adequate role in the rock and soil layer. The bending moment of double pile foundation is positive at the top and negative at the bottom.</span></span></span><span><span><span style="font-family:" capt",serif;"="" pro="" minion=""> </span></span></span><span><span><span style="font-family:" capt",serif;"="" pro="" minion="">Applied oblique load has obvious p-Δ effect.</span></span></span>
基金supported by the National Natural Science Foundation of China(Grant No.51174128)the Specialized Research Fund for the Doctoral Program of Higher Education of China(Grant No.20123718110007).
文摘In this paper,a physical model of coal roadway which is clamped by upper and lower softrock with extra thickness was built according to the characteristics of soft rock strata in china's western mining area.Then,a series of orthogonal numerical experiments were carried out by selecting the strength and stiffness parameters of soft rock and coal seam as well as the in situ stress of soft rock strata as experimental factors and roadway displacements(convergence displacements of sides,displacement of roof to floor)as experimental indexes.By constructing the F statistics with different inspection levels,evaluation method for influence of the experimental factors on stability indexes were defined.Thus,influence degrees of specified parameters on the stability of roadway were divided into five classes as follows:highly significant influence,significant influence,relatively significant influence,little significant influence,and no influence respectively which realize the quantitative analysis of the influence degrees of experimental factors.The finite element calculation results showed that main failure mode of coal roadway that usually showed as tension failure of coal seam in roof and deformation factors of coal seam had the most remarkable effect on roadway displacements.The conclusions provide theoretical basis for further analysis of the mechanism of"roof burst"in roadway maintenance.
基金supported by the National Basic Research Programs of China(2012CB315801,2011CB302901)the Fundamental Research Funds for the Central Universities(2013RC0113,2012RC0120)
文摘In-network caching is one of the most important issues in content centric networking (CCN), which may extremely influence the performance of the caching system. Although much work has been done for in-network caching scheme design in CCN, most of them have not addressed the multiple network attribute parameters jointly during caching algorithm design. Hence, to fill this gap, a new in-network caching based on grey relational analysis (GRA) is proposed. The authors firstly define two newly metric parameters named request influence degree (RID) and cache replacement rate, respectively. The RID indicates the importance of one node along the content delivery path from the view of the interest packets arriving The cache replacement rate is used to denote the caching load of the node. Then combining hops a request traveling from the users and the node traffic, four network attribute parameters are considered during the in-network caching algorithm design. Based on these four network parameters, a GRA based in-network caching algorithm is proposed, which can significantly improve the performance of CCN. Finally, extensive simulation based on ndnSIM is demonstrated that the GRA-based caching scheme can achieve the lower load in the source server and the less average hops than the existing the betweeness (Betw) scheme and the ALWAYS scheme.
基金The Natural Science Foundation of Hunan Province of China(2018JJ2115)
文摘In previous studies the value of ecosystem services was evaluated microscopically by ecological indicators such as soil properties,biomass,carbon storage,oxygen release,water quality,and others.In this paper,the spatial heterogeneity of ecosystem services in Liuyang River basin was studied from the perspective of Geographic Information System(GIS)based spatial relationships by using a combination of geographic data and spatial analysis technologies.The Liuyang River basin was divided into grids with a resolution of 1km×1km.The weights of factors that affect the value of ecosystem services(such as topography,geological disasters,roads,scenic spots,vegetation coverage,and plant net primary productivity)were evaluated using the entropy method and analytic hierarchy process(AHP)in order to investigate the influence of natural and social factors on the value of ecosystem services in a quantitative manner.The results demonstrate that the value of ecosystem services is mainly affected by vegetation coverage,plant net primary productivity,and road network density.The value of ecosystem services grows with the increase in either vegetation coverage,plant net primary productivity,or road network density.Different types of land play different roles in ecosystem services.Cultivated land,grassland,and water each have significant supply and regulating functions while forest has significant regulating and supporting functions.The value of ecosystem services of cultivated land and water that are closely related to human activity is significantly influenced by spatial heterogeneity.In contrast,the effect of spatial heterogeneity on the value of ecosystem services of forest land and grassland that are located in mountains and hills,far away from the human accumulation zone,is insignificant.