A constitutive model of quasi-Newtonian fluid based on the type of flow is used in abrupt planar contraction now.The numerical results from finite element analysis are consistent with experimental data for stress patt...A constitutive model of quasi-Newtonian fluid based on the type of flow is used in abrupt planar contraction now.The numerical results from finite element analysis are consistent with experimental data for stress patterns and velocityprofiles in the flow field. The chain conformations of polymer melts are then investigated in such a planar contraction byusing the phenomenological model with internal parameters proposed by the author. That is, the shape and orientation ofpolymer chain coils are predicted and discussed in different flow regions of the contraction flow field that possess simpleshear flow, extensional flow, vortical flow, and mixed flow respectively.展开更多
Firstly,I point out the problems in the fruit supply chain management.Then through field survey,we know that busywork flow plays a very important role in the fruit supply chain management.I establish the mathematical ...Firstly,I point out the problems in the fruit supply chain management.Then through field survey,we know that busywork flow plays a very important role in the fruit supply chain management.I establish the mathematical model,to derive that the supply chain management of corporate procurement and supply network is the optimal economic model.In terms of the performance of supply chain,I draw the following conclusions:(i) Busywork flow can achieve the supply chain management,and reduces logistics costs in the whole process of circulation;(ii) Busywork flow can improve logistics services for the customers and reduces coordination costs;(iii) The establishment of modern information system can reduce logistics costs;(iv) Busywork flow can improve distribution efficiency and reduce costs;(v) Busywork flow can reduce and avoid the costs of return of goods;(vi) The operation of the busywork flow can achieve integrated transport and business outsourcing to third-party logistics,thereby reducing costs,reducing transport links,reasonably choosing the means of transport,formulating the optimal transportation plan,improving the mode of transport,and increasing the cargo loading amount.(vii) Busywork flow promotes the use of e-commerce.I also express my own views on upgrade version of corporate procurement and supply network.Finally I point out some problems in the existing corporate procurement and supply network,and put forward the following recommendations:developing township-level 4S fruit shop according to the business development,with the functions of purchasing apple,supplying means of agricultural production,providing technical services and developing market;building " corporate ecological orchard" through holding.展开更多
An integral constitutive equation and a set of material functions for describing the strain history of polymer melts were formulated in terms of the Cauchy-Green and Finger tensors. A simple memory function and the de...An integral constitutive equation and a set of material functions for describing the strain history of polymer melts were formulated in terms of the Cauchy-Green and Finger tensors. A simple memory function and the dependence of ηo and τt on M3.4 were derived from the theory of non-linear viscoelasticity with constraints of entanglements for polymer melts and substituted into the Oldroye-Walters-Fredickson constitutive equation. An integral constitutive equation for polymer melts was consequently obtained. Some material functions of the constitutive equation related to certain 'test flow' are examined as follows : (1) simple steady shear flow; (2) steady elongation flow; (3) small-amplitude oscillatory shear flow; (4) stress growth upon the inception of steady shear elongation flow; (5) stress relaxation (modulus and compllance). These theoretical relations for simple steady shear flow were compared with experimental data from our laboratory and references for various polymer melts and concentrated solutions. A good agreement between the theory and experiment was achieved.展开更多
Polymer chain coils with entanglement is a crucial scale of structures in polymer materials since their relaxationtimes are matching practical processing times.Based on the phenomenological model of polymer chain coil...Polymer chain coils with entanglement is a crucial scale of structures in polymer materials since their relaxationtimes are matching practical processing times.Based on the phenomenological model of polymer chain coils and a new finiteelement approach,we have designed a computer software including solver,pre-and post-processing modules,and developeda digital analysis technology for the morphology of polymer chain coils in flow fields(DAMPC).Using this technology wemay simulate the morphology development of chain coils in various flow fields,such as simple shear flow,elongational flow,and any complex flow at transient or steady state.The applications made up to now show that the software predictions arecomparable with experimental results.展开更多
During B-cell development and maturation,the antigen receptor,which is encoded by the immunoglobulin heavy-(IgH) and light-chain genes,rearrange to associate one of a number of variable,diverse,and joining gene segmen...During B-cell development and maturation,the antigen receptor,which is encoded by the immunoglobulin heavy-(IgH) and light-chain genes,rearrange to associate one of a number of variable,diverse,and joining gene segments.A single mature B-cell expresses an IgH chain and either a kappa or lambda light chain,which is known as allelic or isotypic exclusion.In normal or reactive conditions,lymphoid cells comprise the mixtures of lymphocytes with either kappa or lambda expression.展开更多
Debris flows and landslides, extensively developing and frequently occurring along Parlung Zangbo, seriously damage the Highway from Sichuan to Tiebt(G318) at Bomi County. The disastrous debris flows of the Tianmo Wat...Debris flows and landslides, extensively developing and frequently occurring along Parlung Zangbo, seriously damage the Highway from Sichuan to Tiebt(G318) at Bomi County. The disastrous debris flows of the Tianmo Watershed on Sept. 4, 2007, July 25, 2010 and Sept. 4, 2010, blocked Parlung Zangbo River and produced dammed lakes, whose outburst flow made 50 m high terrace collapse at the opposite bank due to intense scouring on the foot of the terrace. As a result, the traffic was interrupted for 16 days in 2010 because that 900 m highway base was destructed and 430 m ruined. These debris flows were initiated by the glacial melting which was induced by continuous higher temperature and the following intensive rainfall, and expanded by moraines along channels and then blocked Parlung Zangbo. At the outlet of watershed,the density, velocity and peak discharge of debris flow was 2.06 t/m3, 12.7 m/s and 3334 m3/s, respectively. When the discharge at the outlet and the deposition volume into river exceeds 2125 m3/s and 126×103 m3, respectively, debris flow will completely blocked Parlung Zangbo. Moreover,if the shear stress of river flow on the foot of terrace and the inclination angel of terrace overruns 0. 377 N/m2 and 26°, respectively, the unconsolidated terrace will be eroded by outburst flow and collapse. It was strongly recommended for mitigation that identify and evade disastrous debris flows, reduce the junction angel of channels between river and watershed, build protecting wall for highway base and keep appropriate distance between highway and the edge of unconsolidated terrace.展开更多
The Wulipo landslide, triggered by heavy rainfall on July 10, 2013, transformed into debris flow,resulted in the destruction of 12 houses, 44 deaths, and 117 missing. Our systematic investigation has led to the follow...The Wulipo landslide, triggered by heavy rainfall on July 10, 2013, transformed into debris flow,resulted in the destruction of 12 houses, 44 deaths, and 117 missing. Our systematic investigation has led to the following results and to a new understanding about the formation and evolution process of this hazard. The fundamental factors of the formation of the landslide are a high-steep free surface at the front of the slide mass and the sandstone-mudstone mixed stratum structure of the slope. The inducing factor of the landslide is hydrostatic and hydrodynamic pressure change caused by heavy continuous rainfall. The geological mechanical model of the landslide can be summarized as "instability-translational slide-tension fracture-collapse" and the formation mechanism as "translational landslide induced by heavy rainfall". The total volume of the landslide is 124.6×104 m3, and 16.3% of the sliding mass was dropped down from the cliff and transformed into debris flow during the sliding process, which enlarged 46.7% of the original sliding deposit area. The final accumulation area is found to be 9.2×104 m2. The hazard is a typical example of a disaster chain involving landslide and its induced debris flow. The concealment and disaster chain effect is the main reason for the heavy damage. In future risk assessment, it is suggested to enhance the research onpotential landslide identification for weakly intercalated slopes. By considering the influence of the behaviors of landslide-induced debris flow, the disaster area could be determined more reasonably.展开更多
In this paper, we focus on the intermediate nodes of network and quantification of level of commodity and its cost on each node because intermediate nodes have stocking capacities which we generally see in the supply ...In this paper, we focus on the intermediate nodes of network and quantification of level of commodity and its cost on each node because intermediate nodes have stocking capacities which we generally see in the supply chain network. The commodity is supplied from a node to node in response to the power form of demand at a particular time. Since the traffic intensity of the demand of commodity also affects the flow of the commodity in the network, hence study of flow of commodity in the network is believed to be a significant contribution in this area. Several cases of quantifying the level of commodity in different situations as well as the cost analysis of incoming and outgoing commodity at a particular node have been thoroughly discussed in the paper. The present problem, presumably seeks to contribute to managerial decision making in supply chain network.展开更多
In this paper, we demonstrate that the eco-industrial network equilibrium model of link flow version previously introduced can be reformulated as a transportation network equilibrium problem of path flow version. Then...In this paper, we demonstrate that the eco-industrial network equilibrium model of link flow version previously introduced can be reformulated as a transportation network equilibrium problem of path flow version. Then, some methodological tools mainly applied in the field of transportation science can be used to discuss the eco-industrial chain network problem. What the highlighted contribution lies in is that the paper not only expands theory of supply chain model with reducing path flow but also generalizes the traditional transportation network equilibrium problem by new applications.展开更多
基金This work was supported by the research grants from the National Nature Science Foundation of China (No. 20174024) and the Special Founds for Major State Basic Research Projects (G199906408)
文摘A constitutive model of quasi-Newtonian fluid based on the type of flow is used in abrupt planar contraction now.The numerical results from finite element analysis are consistent with experimental data for stress patterns and velocityprofiles in the flow field. The chain conformations of polymer melts are then investigated in such a planar contraction byusing the phenomenological model with internal parameters proposed by the author. That is, the shape and orientation ofpolymer chain coils are predicted and discussed in different flow regions of the contraction flow field that possess simpleshear flow, extensional flow, vortical flow, and mixed flow respectively.
文摘Firstly,I point out the problems in the fruit supply chain management.Then through field survey,we know that busywork flow plays a very important role in the fruit supply chain management.I establish the mathematical model,to derive that the supply chain management of corporate procurement and supply network is the optimal economic model.In terms of the performance of supply chain,I draw the following conclusions:(i) Busywork flow can achieve the supply chain management,and reduces logistics costs in the whole process of circulation;(ii) Busywork flow can improve logistics services for the customers and reduces coordination costs;(iii) The establishment of modern information system can reduce logistics costs;(iv) Busywork flow can improve distribution efficiency and reduce costs;(v) Busywork flow can reduce and avoid the costs of return of goods;(vi) The operation of the busywork flow can achieve integrated transport and business outsourcing to third-party logistics,thereby reducing costs,reducing transport links,reasonably choosing the means of transport,formulating the optimal transportation plan,improving the mode of transport,and increasing the cargo loading amount.(vii) Busywork flow promotes the use of e-commerce.I also express my own views on upgrade version of corporate procurement and supply network.Finally I point out some problems in the existing corporate procurement and supply network,and put forward the following recommendations:developing township-level 4S fruit shop according to the business development,with the functions of purchasing apple,supplying means of agricultural production,providing technical services and developing market;building " corporate ecological orchard" through holding.
文摘An integral constitutive equation and a set of material functions for describing the strain history of polymer melts were formulated in terms of the Cauchy-Green and Finger tensors. A simple memory function and the dependence of ηo and τt on M3.4 were derived from the theory of non-linear viscoelasticity with constraints of entanglements for polymer melts and substituted into the Oldroye-Walters-Fredickson constitutive equation. An integral constitutive equation for polymer melts was consequently obtained. Some material functions of the constitutive equation related to certain 'test flow' are examined as follows : (1) simple steady shear flow; (2) steady elongation flow; (3) small-amplitude oscillatory shear flow; (4) stress growth upon the inception of steady shear elongation flow; (5) stress relaxation (modulus and compllance). These theoretical relations for simple steady shear flow were compared with experimental data from our laboratory and references for various polymer melts and concentrated solutions. A good agreement between the theory and experiment was achieved.
基金This work was supported by the research grants from the National Natural Science Foundation of China(No.50290090No.20204007+2 种基金No.20174024)National 863 project of China(No.2002AA336120)the Doctoral Foundation of National Education Committee of China(
文摘Polymer chain coils with entanglement is a crucial scale of structures in polymer materials since their relaxationtimes are matching practical processing times.Based on the phenomenological model of polymer chain coils and a new finiteelement approach,we have designed a computer software including solver,pre-and post-processing modules,and developeda digital analysis technology for the morphology of polymer chain coils in flow fields(DAMPC).Using this technology wemay simulate the morphology development of chain coils in various flow fields,such as simple shear flow,elongational flow,and any complex flow at transient or steady state.The applications made up to now show that the software predictions arecomparable with experimental results.
文摘During B-cell development and maturation,the antigen receptor,which is encoded by the immunoglobulin heavy-(IgH) and light-chain genes,rearrange to associate one of a number of variable,diverse,and joining gene segments.A single mature B-cell expresses an IgH chain and either a kappa or lambda light chain,which is known as allelic or isotypic exclusion.In normal or reactive conditions,lymphoid cells comprise the mixtures of lymphocytes with either kappa or lambda expression.
基金supported by the Key Program of National Natural Science Found of China(Grant No.41030742)the Grand Program of National Natural Science Found of China(Grant No.41190084)
文摘Debris flows and landslides, extensively developing and frequently occurring along Parlung Zangbo, seriously damage the Highway from Sichuan to Tiebt(G318) at Bomi County. The disastrous debris flows of the Tianmo Watershed on Sept. 4, 2007, July 25, 2010 and Sept. 4, 2010, blocked Parlung Zangbo River and produced dammed lakes, whose outburst flow made 50 m high terrace collapse at the opposite bank due to intense scouring on the foot of the terrace. As a result, the traffic was interrupted for 16 days in 2010 because that 900 m highway base was destructed and 430 m ruined. These debris flows were initiated by the glacial melting which was induced by continuous higher temperature and the following intensive rainfall, and expanded by moraines along channels and then blocked Parlung Zangbo. At the outlet of watershed,the density, velocity and peak discharge of debris flow was 2.06 t/m3, 12.7 m/s and 3334 m3/s, respectively. When the discharge at the outlet and the deposition volume into river exceeds 2125 m3/s and 126×103 m3, respectively, debris flow will completely blocked Parlung Zangbo. Moreover,if the shear stress of river flow on the foot of terrace and the inclination angel of terrace overruns 0. 377 N/m2 and 26°, respectively, the unconsolidated terrace will be eroded by outburst flow and collapse. It was strongly recommended for mitigation that identify and evade disastrous debris flows, reduce the junction angel of channels between river and watershed, build protecting wall for highway base and keep appropriate distance between highway and the edge of unconsolidated terrace.
基金funded by the key project of Sichuan province (Grand No. 2014SZ0163)the National Natural Science Foundation of China (Grant No. 41372301)the Key Deployment Project of Chinese Academy of Sciences (Grant No. KZZD-EW-05-01-02)
文摘The Wulipo landslide, triggered by heavy rainfall on July 10, 2013, transformed into debris flow,resulted in the destruction of 12 houses, 44 deaths, and 117 missing. Our systematic investigation has led to the following results and to a new understanding about the formation and evolution process of this hazard. The fundamental factors of the formation of the landslide are a high-steep free surface at the front of the slide mass and the sandstone-mudstone mixed stratum structure of the slope. The inducing factor of the landslide is hydrostatic and hydrodynamic pressure change caused by heavy continuous rainfall. The geological mechanical model of the landslide can be summarized as "instability-translational slide-tension fracture-collapse" and the formation mechanism as "translational landslide induced by heavy rainfall". The total volume of the landslide is 124.6×104 m3, and 16.3% of the sliding mass was dropped down from the cliff and transformed into debris flow during the sliding process, which enlarged 46.7% of the original sliding deposit area. The final accumulation area is found to be 9.2×104 m2. The hazard is a typical example of a disaster chain involving landslide and its induced debris flow. The concealment and disaster chain effect is the main reason for the heavy damage. In future risk assessment, it is suggested to enhance the research onpotential landslide identification for weakly intercalated slopes. By considering the influence of the behaviors of landslide-induced debris flow, the disaster area could be determined more reasonably.
文摘In this paper, we focus on the intermediate nodes of network and quantification of level of commodity and its cost on each node because intermediate nodes have stocking capacities which we generally see in the supply chain network. The commodity is supplied from a node to node in response to the power form of demand at a particular time. Since the traffic intensity of the demand of commodity also affects the flow of the commodity in the network, hence study of flow of commodity in the network is believed to be a significant contribution in this area. Several cases of quantifying the level of commodity in different situations as well as the cost analysis of incoming and outgoing commodity at a particular node have been thoroughly discussed in the paper. The present problem, presumably seeks to contribute to managerial decision making in supply chain network.
基金Sponsored by the Fundamental Research Funds for the Central Universitiesthe Research Funds of Renmin University of China(Grant No.13XNH169)
文摘In this paper, we demonstrate that the eco-industrial network equilibrium model of link flow version previously introduced can be reformulated as a transportation network equilibrium problem of path flow version. Then, some methodological tools mainly applied in the field of transportation science can be used to discuss the eco-industrial chain network problem. What the highlighted contribution lies in is that the paper not only expands theory of supply chain model with reducing path flow but also generalizes the traditional transportation network equilibrium problem by new applications.