The observation of geomagnetic field variations is an important approach to studying earthquake precursors.Since 1987,the China Earthquake Administration has explored this seismomagnetic relationship.In particular,the...The observation of geomagnetic field variations is an important approach to studying earthquake precursors.Since 1987,the China Earthquake Administration has explored this seismomagnetic relationship.In particular,they studied local magnetic field anomalies over the Chinese mainland for earthquake prediction.Owing to the years of research on the seismomagnetic relationship,earthquake prediction experts have concluded that the compressive magnetic effect,tectonic magnetic effect,electric magnetic fluid effect,and other factors contribute to preearthquake magnetic anomalies.However,this involves a small magnitude of magnetic field changes.It is difficult to relate them to the abnormal changes of the extremely large magnetic field in regions with extreme earthquakes owing to the high cost of professional geomagnetic equipment,thereby limiting large-scale deployment.Moreover,it is difficult to obtain strong magnetic field changes before an earthquake.The Tianjin Earthquake Agency has developed low-cost geomagnetic field observation equipment through the Beijing–Tianjin–Hebei geomagnetic equipment test project.The new system was used to test the availability of equipment and determine the findings based on big data..展开更多
This review presents a comprehensive techno-economic and life-cycle assessment of sustainable aviation fuel(SAF)production from biomass.The critical need for transitioning towards environmentally sustainable alternati...This review presents a comprehensive techno-economic and life-cycle assessment of sustainable aviation fuel(SAF)production from biomass.The critical need for transitioning towards environmentally sustainable alternatives for liquid fuel and aviation industry is first discussed.Key insights encompass the evolutionary progression of biofuel production from first-generation to second-generation biofuels,with a focus on utilizing non-food sources like woody biomass for enhanced sustainability.Available data from the literature on techno-economic assessments of various SAF production pathways are analyzed including production costs,conversion efficiency,and scalability.Moreover,results of lifecycle assessments associated with different SAF production pathways are presented,providing essential insights for decision-making processes.The challenges of scaling up woody biomass-based SAF production are discussed based on the assessment results,and recommendations are proposed to steer stakeholders towards a greener and more sustainable trajectory for aviation operations.展开更多
Taking the construction of PPP project of Guangzhou North Railway Station Comprehensive Transportation Hub as an example,the related measures of construction project quality management and cost control are discussed i...Taking the construction of PPP project of Guangzhou North Railway Station Comprehensive Transportation Hub as an example,the related measures of construction project quality management and cost control are discussed in detail,and it is hoped to have reference.展开更多
CdS/ZnS core-shell microparticles were prepared by a simple two-step method combining ultrasonic spray pyrolysis and chemical bath deposition.The core-shell structures showed enhanced photocatalytic properties compare...CdS/ZnS core-shell microparticles were prepared by a simple two-step method combining ultrasonic spray pyrolysis and chemical bath deposition.The core-shell structures showed enhanced photocatalytic properties compared with those of CdS or ZnS spherical particles.CdS/ZnS photocatalysts with different amount of ZnS loaded as shells were prepared by adjusting the concentrations of Zn and S precursors during synthesis.The optical properties and photocatalytic activity for hydrogen production were investigated and the amount of ZnS loaded as shell was optimized.Thermal annealing and hydrothermal sulfurization treatments were applied to the core-shell structure and both treatments enhanced the material's photocatalytic activity and stability by eliminating crystalline defects and surface states.The result showed that thermal annealing treatment improved the bulk crystallinity and hydrothermal sulfurization improved the surface properties.The sample subjected to both treatments showed the highest photocatalytic activity.These results indicate that CdS/ZnS core-shell microspheres are a simple structure that can be used as efficient photocatalysts.The hydrothermal sulfurization treatment may also be a useful surface treatment for metal sulfide photocatalysts.The simple two-step method provides a promising approach to the large-scale synthesis of core-shell microsphere catalysts.展开更多
The ecological costs of open pit metal mining are quantified, which include lost value of direct eco-services, lost value of indirect eco-services, prevention and restoration costs, and cost of carbon emission from en...The ecological costs of open pit metal mining are quantified, which include lost value of direct eco-services, lost value of indirect eco-services, prevention and restoration costs, and cost of carbon emission from energy consumption. These ecological costs are incorporated in an iterative ultimate pit optimization algorithm. A case study is presented to demonstrate the influence of ecological costs on pit design outcome. The results show that it is possible to internalize ecological costs in mine designs. The pit optimization outcome shifts considerably to the conservative side and the profitability decreases substantially when ecological costs are accounted for.展开更多
A VDMOS integrated in a 170V scan-driver chip of a plasma display panel (PDP) is described,which is based on epitaxial bipolar-CMOS-DMOS (BCD) technology. Some key considerations and parameters of the design are d...A VDMOS integrated in a 170V scan-driver chip of a plasma display panel (PDP) is described,which is based on epitaxial bipolar-CMOS-DMOS (BCD) technology. Some key considerations and parameters of the design are discussed. The thickness of epitaxial layer is 17μm, the area of a single VDMOS structure cell is 324μm^2, and only 18 photoetching steps are needed in the development process. It is also compatible with standard CMOS, bipo- lar,and p-LDMOS devices. The breakdown voltage of VDMOS in the process control module (PCM) is more than 200V. Five kinds of VDMOS modules are integrated in 64 channel PDP scan-driver IC, and on-line system verifica- tion is done on a LG-model-42v6 PDP.展开更多
In order to eliminate semantic heterogeneity and implement semantic combination in web information integration, the classification ontology is introduced into web information integration. It constructs a standard clas...In order to eliminate semantic heterogeneity and implement semantic combination in web information integration, the classification ontology is introduced into web information integration. It constructs a standard classification ontology based on web-glossary by extracting classified structures of websites and building mappings between them in order to get unified views. Mapping is defined by calculating concept subordinate matching degrees, concept associate matching degrees and concept dominate matching degrees. A web information integration system is realized, which can effectively solve the problem of classification semantic heterogeneity and implement the integration of web information source and the personal configuration of users.展开更多
Optimal control of multi-assets liquidation in view of volatility risk was studied. The analytical solution of optimal strategy was achieved with the calculus of variation. Numerical examples and graphical illustratio...Optimal control of multi-assets liquidation in view of volatility risk was studied. The analytical solution of optimal strategy was achieved with the calculus of variation. Numerical examples and graphical illustrations were also given. The conclusion shows that the optimal strategy is the linear combination of time's hyperbolic sine and hyperbolic cosine. The investor's attitude towards risk can influence the optimal strategy. In order to avoid the uncertainty of the execution cost, the investor with high risk aversion liquidates assets rapidly in the early period. The decrease of liquidation loss is at the cost of the increase of the volatility level.展开更多
In order to reduce the cost of high performance polyvinyl alcohol(PVA) fiber reinforced cementitious material(called engineered cementitious composites,ECC),a ductile ECC material is developed using domestic PVA f...In order to reduce the cost of high performance polyvinyl alcohol(PVA) fiber reinforced cementitious material(called engineered cementitious composites,ECC),a ductile ECC material is developed using domestic PVA fibers along with other local ingredients,such as fly ash,cement and sand.In addition to the economic analysis of ECC,the four-point bending test and the optical microscope are employed to investigate the deflection capacity of ECC,its crack width and the occurrence of the self-healing phenomenon.The experimental results suggest that ECC made with domestic ingredients exhibits larger deformability and the average crack width is controlled around 60 μm.Furthermore,the self-healing behavior is observed in cracks of the specimens after cycles of wet and dry curing.The economic analysis shows that the cost of ECC can be greatly reduced via employing domestic PVA fibers.It is,therefore,feasible to produce low cost ECC material employing domestic PVA fibers,while simultaneously retaining high material ductility.展开更多
A new arrival and departure flight classification method based on the transitive closure algorithm (TCA) is proposed. Firstly, the fuzzy set theory and the transitive closure algorithm are introduced. Then four diff...A new arrival and departure flight classification method based on the transitive closure algorithm (TCA) is proposed. Firstly, the fuzzy set theory and the transitive closure algorithm are introduced. Then four different factors are selected to establish the flight classification model and a method is given to calculate the delay cost for each class. Finally, the proposed method is implemented in the sequencing problems of flights in a terminal area, and results are compared with that of the traditional classification method(TCM). Results show that the new classification model is effective in reducing the expenses of flight delays, thus optimizing the sequences of arrival and departure flights, and improving the efficiency of air traffic control.展开更多
Expenditure on wells constitute a significant part of the operational costs for a petroleum enterprise, where most of the cost results from drilling. This has prompted drilling departments to continuously look for wa...Expenditure on wells constitute a significant part of the operational costs for a petroleum enterprise, where most of the cost results from drilling. This has prompted drilling departments to continuously look for ways to reduce their drilling costs and be as efficient as possible. A system called the Drilling Comprehensive Information Management and Application System (DCIMAS) is developed and presented here, with an aim at collecting, storing and making full use of the valuable well data and information relating to all drilling activities and operations. The DCIMAS comprises three main parts, including a data collection and transmission system, a data warehouse (DW) management system, and an integrated platform of core applications. With the support of the application platform, the DW management system is introduced, whereby the operation data are captured at well sites and transmitted electronically to a data warehouse via transmission equipment and ETL (extract, transformation and load) tools. With the high quality of the data guaranteed, our central task is to make the best use of the operation data and information for drilling analysis and to provide further information to guide later production stages. Applications have been developed and integrated on a uniform platform to interface directly with different layers of the multi-tier DW. Now, engineers in every department spend less time on data handling and more time on applying technology in their real work with the system.展开更多
Aiming to minimize the total production costs in a single planning period, a nonlinear integer programming model for remanufacturing production plans is established considering the influence of different qualities of ...Aiming to minimize the total production costs in a single planning period, a nonlinear integer programming model for remanufacturing production plans is established considering the influence of different qualities of returns acting on production cost. Three different remanufacturing and discarding strategies are adopted to analyze the change rules of the total production costs. The results returns is greater than indicate that when the number of remanufacturing returns of high the demand, preferentially quality and discarding those of low quality can bring better economic benefits due to manufacturing cost reduction. However, when the number of returns is smaller than the demand, there is no need to consider grading of returns, whereas new demand of remanufacturing. parts are required to satisfy the展开更多
A two-level supply chain model involving one supplier and one retailer with linear demand is developed, and supply chain coordination mechanisms under asymmetric information (the retailer' s cost structure is asymme...A two-level supply chain model involving one supplier and one retailer with linear demand is developed, and supply chain coordination mechanisms under asymmetric information (the retailer' s cost structure is asymmetric information) are proposed by employing game theory in two scenarios: coordination mechanisms under asymmetric information in a regular scenario (without disruption); and coordination mechanisms under asymmetric information in an irregular scenario ( with retailer cost disruptions). It is optimal for the supply chain to maintain the original production plan and to guarantee a steadily running system if variations of retailer costs are sufficiently low and do not exceed an upper bound. This shows that the original production plan has certain robustness under disruptions. Decisions must be re-made if a retailer' s cost change is greater and exceeds an upper bound. Impacts of retailer cost disruptions on the order quantity, the retail price, the wholesale price and each party' s as well as the system' s expected profits are investigated through numerical analyses.展开更多
The inherent mechanism of size effect in micro-sheet material behavior of plastic forming was explained by the surface layer model and theory of metal crystal plasticity. A size-dependant constitutive model based on t...The inherent mechanism of size effect in micro-sheet material behavior of plastic forming was explained by the surface layer model and theory of metal crystal plasticity. A size-dependant constitutive model based on the surface layer model was established by introducing the scale parameters and modifying the classical Hall-Petch equation. The influence of the geometric dimensions and the grain size on the flow behavior of the material was discussed using the new material constitutive model. The results show that, the flow stress decreases while the sheet metal thickness decreases when the grain size keeps constant, and the micro-sheet metal with a larger grain size is more easily to be influenced by the size effects. The material constitutive model established is validated by the stress-strain curve of the micro-sheet metal with different thicknesses derived from the tensile experiments. The rationality of the material model is verified by the fact that the calculation results are consistent with the experimental results.展开更多
Durability zonation standard (DZS) is proposed to provide useful parameters for durable concrete structure design. It deals not only with the influence of environment on structures, but also with types, functions an...Durability zonation standard (DZS) is proposed to provide useful parameters for durable concrete structure design. It deals not only with the influence of environment on structures, but also with types, functions and importance of structures based on the theory of life cycle cost(LCC). First, the basic concept of DZS for concrete structure design is defined. Then the basic principles for DZS are established. The factors for zonation according to natural environmental conditions and structural importance are identified. The usefulness of DZS by citing a real application for concrete highway bridges in Zhejiang Province is demonstrated. Finally, durability regulations are provided accordingly to zonation.展开更多
China's economic growth is heavily influenced by exports, while reconciling environmental regulation and economic growth requires handling the relationship between environmental regulation and industrial competitiven...China's economic growth is heavily influenced by exports, while reconciling environmental regulation and economic growth requires handling the relationship between environmental regulation and industrial competitiveness well. The effects of environmental regulation on industrial competitiveness are largely subject to the institutional design of environmental regulation. Despite numerous studies on the relationship between environmental regulation and industrial competitiveness, a consensus has yet to be reached. Aside from differences in research methodology, these studies failed to give sufficient consideration to the impact of environmental regulation on industrial competitiveness. Such effects can be negative or positive depending on the design of environmental regulatory policy. This paper has investigated the relationship between environmental regulation and the competitiveness of China's iron and steel industry and discovered that tighter environmental regulation does not diminish the competitiveness of the iron and steel industry since the policy design of environmental regulation accommodates the tolerance of advanced production capacity and includes a reasonable cost sharing mechanism. This discovery is of important reference for China to develop rational policy design to balance the relationship between environmental regulation and industrial competitiveness.展开更多
Traditionally governance structures are classified into "hierarchy or market" or "equity or non-equity." However,such classifications may not be effective in characterizing all governance structures of research an...Traditionally governance structures are classified into "hierarchy or market" or "equity or non-equity." However,such classifications may not be effective in characterizing all governance structures of research and development(R D) alliances.Therefore,the first objective of this study is to investigate why there exist different organizational governance structures in managing R D alliances;the second objective of this study is to give strategic advice in choosing appropriate forms with respect to various characteristics of R D alliances.Through the theoretical lens that integrate both transaction cost economics(TCE) and the resource-based view(RBV),a model that focuses on six major factors is developed for determining governance structure choices,namely,technological uncertainty,cultural difference,asset specificity,technology complementarity,appropriability of the individual firm's know-how,and trust.An R D alliance with higher technological uncertainty,larger cultural differences,and greater concerns for protecting an individual's know-how is more likely to adopt non-integrated alliances as the governing structure.An R D alliance with a higher degree of asset-specificity,greater technology complementarity and greater trust among partnering organizations is more likely to adopt integrated alliances as the governing structure;an R D alliance in the face of lower technological uncertainty will tend to adopt integrated alliances.The more aligned the choice of the governance structure with its determinants,the better the R D alliance will perform,and vice versa.展开更多
基金supported by the Spark Program of Earthquake Science and Technology(No.XH23003C).
文摘The observation of geomagnetic field variations is an important approach to studying earthquake precursors.Since 1987,the China Earthquake Administration has explored this seismomagnetic relationship.In particular,they studied local magnetic field anomalies over the Chinese mainland for earthquake prediction.Owing to the years of research on the seismomagnetic relationship,earthquake prediction experts have concluded that the compressive magnetic effect,tectonic magnetic effect,electric magnetic fluid effect,and other factors contribute to preearthquake magnetic anomalies.However,this involves a small magnitude of magnetic field changes.It is difficult to relate them to the abnormal changes of the extremely large magnetic field in regions with extreme earthquakes owing to the high cost of professional geomagnetic equipment,thereby limiting large-scale deployment.Moreover,it is difficult to obtain strong magnetic field changes before an earthquake.The Tianjin Earthquake Agency has developed low-cost geomagnetic field observation equipment through the Beijing–Tianjin–Hebei geomagnetic equipment test project.The new system was used to test the availability of equipment and determine the findings based on big data..
文摘This review presents a comprehensive techno-economic and life-cycle assessment of sustainable aviation fuel(SAF)production from biomass.The critical need for transitioning towards environmentally sustainable alternatives for liquid fuel and aviation industry is first discussed.Key insights encompass the evolutionary progression of biofuel production from first-generation to second-generation biofuels,with a focus on utilizing non-food sources like woody biomass for enhanced sustainability.Available data from the literature on techno-economic assessments of various SAF production pathways are analyzed including production costs,conversion efficiency,and scalability.Moreover,results of lifecycle assessments associated with different SAF production pathways are presented,providing essential insights for decision-making processes.The challenges of scaling up woody biomass-based SAF production are discussed based on the assessment results,and recommendations are proposed to steer stakeholders towards a greener and more sustainable trajectory for aviation operations.
文摘Taking the construction of PPP project of Guangzhou North Railway Station Comprehensive Transportation Hub as an example,the related measures of construction project quality management and cost control are discussed in detail,and it is hoped to have reference.
基金supported by the National Natural Science Foundation of China(51202186,51323011)the Fundamental Research Funds for the Central University(xjj2016039)~~
文摘CdS/ZnS core-shell microparticles were prepared by a simple two-step method combining ultrasonic spray pyrolysis and chemical bath deposition.The core-shell structures showed enhanced photocatalytic properties compared with those of CdS or ZnS spherical particles.CdS/ZnS photocatalysts with different amount of ZnS loaded as shells were prepared by adjusting the concentrations of Zn and S precursors during synthesis.The optical properties and photocatalytic activity for hydrogen production were investigated and the amount of ZnS loaded as shell was optimized.Thermal annealing and hydrothermal sulfurization treatments were applied to the core-shell structure and both treatments enhanced the material's photocatalytic activity and stability by eliminating crystalline defects and surface states.The result showed that thermal annealing treatment improved the bulk crystallinity and hydrothermal sulfurization improved the surface properties.The sample subjected to both treatments showed the highest photocatalytic activity.These results indicate that CdS/ZnS core-shell microspheres are a simple structure that can be used as efficient photocatalysts.The hydrothermal sulfurization treatment may also be a useful surface treatment for metal sulfide photocatalysts.The simple two-step method provides a promising approach to the large-scale synthesis of core-shell microsphere catalysts.
基金Project(50974041)supported by the National Natural Science Foundation of ChinaProject(NCET-11-0073)supported by Program for New Century Excellent Talents in University of Ministry of Education of China+1 种基金Project(201102065)supported by the Natural Science Foundation of Liaoning Province,ChinaProject(2012921075)supported by the Ten Million Talent Project of Liaoning Province,China
文摘The ecological costs of open pit metal mining are quantified, which include lost value of direct eco-services, lost value of indirect eco-services, prevention and restoration costs, and cost of carbon emission from energy consumption. These ecological costs are incorporated in an iterative ultimate pit optimization algorithm. A case study is presented to demonstrate the influence of ecological costs on pit design outcome. The results show that it is possible to internalize ecological costs in mine designs. The pit optimization outcome shifts considerably to the conservative side and the profitability decreases substantially when ecological costs are accounted for.
文摘A VDMOS integrated in a 170V scan-driver chip of a plasma display panel (PDP) is described,which is based on epitaxial bipolar-CMOS-DMOS (BCD) technology. Some key considerations and parameters of the design are discussed. The thickness of epitaxial layer is 17μm, the area of a single VDMOS structure cell is 324μm^2, and only 18 photoetching steps are needed in the development process. It is also compatible with standard CMOS, bipo- lar,and p-LDMOS devices. The breakdown voltage of VDMOS in the process control module (PCM) is more than 200V. Five kinds of VDMOS modules are integrated in 64 channel PDP scan-driver IC, and on-line system verifica- tion is done on a LG-model-42v6 PDP.
基金The National Key Technologies R&D Program ofChina during the10th Five-Year Plan Period (No.2004BA721A05).
文摘In order to eliminate semantic heterogeneity and implement semantic combination in web information integration, the classification ontology is introduced into web information integration. It constructs a standard classification ontology based on web-glossary by extracting classified structures of websites and building mappings between them in order to get unified views. Mapping is defined by calculating concept subordinate matching degrees, concept associate matching degrees and concept dominate matching degrees. A web information integration system is realized, which can effectively solve the problem of classification semantic heterogeneity and implement the integration of web information source and the personal configuration of users.
文摘Optimal control of multi-assets liquidation in view of volatility risk was studied. The analytical solution of optimal strategy was achieved with the calculus of variation. Numerical examples and graphical illustrations were also given. The conclusion shows that the optimal strategy is the linear combination of time's hyperbolic sine and hyperbolic cosine. The investor's attitude towards risk can influence the optimal strategy. In order to avoid the uncertainty of the execution cost, the investor with high risk aversion liquidates assets rapidly in the early period. The decrease of liquidation loss is at the cost of the increase of the volatility level.
基金The National Natural Science Foundation of China (No.51008071,51278097)the Natural Science Foundation of Jiangsu Province(No.BK2010413)+2 种基金Teaching & Research Excellence Grant for Young Faculty Member at Southeast Universitythe Program for Special Talents in Six Major Fields of Jiangsu Province(No.2011-JZ-011)the Scientific Research Innovation Project for College Graduates in Jiangsu Province(No.CXLX_0136)
文摘In order to reduce the cost of high performance polyvinyl alcohol(PVA) fiber reinforced cementitious material(called engineered cementitious composites,ECC),a ductile ECC material is developed using domestic PVA fibers along with other local ingredients,such as fly ash,cement and sand.In addition to the economic analysis of ECC,the four-point bending test and the optical microscope are employed to investigate the deflection capacity of ECC,its crack width and the occurrence of the self-healing phenomenon.The experimental results suggest that ECC made with domestic ingredients exhibits larger deformability and the average crack width is controlled around 60 μm.Furthermore,the self-healing behavior is observed in cracks of the specimens after cycles of wet and dry curing.The economic analysis shows that the cost of ECC can be greatly reduced via employing domestic PVA fibers.It is,therefore,feasible to produce low cost ECC material employing domestic PVA fibers,while simultaneously retaining high material ductility.
文摘A new arrival and departure flight classification method based on the transitive closure algorithm (TCA) is proposed. Firstly, the fuzzy set theory and the transitive closure algorithm are introduced. Then four different factors are selected to establish the flight classification model and a method is given to calculate the delay cost for each class. Finally, the proposed method is implemented in the sequencing problems of flights in a terminal area, and results are compared with that of the traditional classification method(TCM). Results show that the new classification model is effective in reducing the expenses of flight delays, thus optimizing the sequences of arrival and departure flights, and improving the efficiency of air traffic control.
文摘Expenditure on wells constitute a significant part of the operational costs for a petroleum enterprise, where most of the cost results from drilling. This has prompted drilling departments to continuously look for ways to reduce their drilling costs and be as efficient as possible. A system called the Drilling Comprehensive Information Management and Application System (DCIMAS) is developed and presented here, with an aim at collecting, storing and making full use of the valuable well data and information relating to all drilling activities and operations. The DCIMAS comprises three main parts, including a data collection and transmission system, a data warehouse (DW) management system, and an integrated platform of core applications. With the support of the application platform, the DW management system is introduced, whereby the operation data are captured at well sites and transmitted electronically to a data warehouse via transmission equipment and ETL (extract, transformation and load) tools. With the high quality of the data guaranteed, our central task is to make the best use of the operation data and information for drilling analysis and to provide further information to guide later production stages. Applications have been developed and integrated on a uniform platform to interface directly with different layers of the multi-tier DW. Now, engineers in every department spend less time on data handling and more time on applying technology in their real work with the system.
基金The National Natural Science Foundation of China(No.70671022)
文摘Aiming to minimize the total production costs in a single planning period, a nonlinear integer programming model for remanufacturing production plans is established considering the influence of different qualities of returns acting on production cost. Three different remanufacturing and discarding strategies are adopted to analyze the change rules of the total production costs. The results returns is greater than indicate that when the number of remanufacturing returns of high the demand, preferentially quality and discarding those of low quality can bring better economic benefits due to manufacturing cost reduction. However, when the number of returns is smaller than the demand, there is no need to consider grading of returns, whereas new demand of remanufacturing. parts are required to satisfy the
基金The National Natural Science Foundation of China(No70671021)Jiangsu Postdoctoral Foundation (No0601015C)
文摘A two-level supply chain model involving one supplier and one retailer with linear demand is developed, and supply chain coordination mechanisms under asymmetric information (the retailer' s cost structure is asymmetric information) are proposed by employing game theory in two scenarios: coordination mechanisms under asymmetric information in a regular scenario (without disruption); and coordination mechanisms under asymmetric information in an irregular scenario ( with retailer cost disruptions). It is optimal for the supply chain to maintain the original production plan and to guarantee a steadily running system if variations of retailer costs are sufficiently low and do not exceed an upper bound. This shows that the original production plan has certain robustness under disruptions. Decisions must be re-made if a retailer' s cost change is greater and exceeds an upper bound. Impacts of retailer cost disruptions on the order quantity, the retail price, the wholesale price and each party' s as well as the system' s expected profits are investigated through numerical analyses.
基金Project(50975163)supported by the National Natural Science Foundation of ChinaProject(IRT0931)supported by Program for Changjiang Scholars and Innovative Research Team in University of Ministry of Education of China
文摘The inherent mechanism of size effect in micro-sheet material behavior of plastic forming was explained by the surface layer model and theory of metal crystal plasticity. A size-dependant constitutive model based on the surface layer model was established by introducing the scale parameters and modifying the classical Hall-Petch equation. The influence of the geometric dimensions and the grain size on the flow behavior of the material was discussed using the new material constitutive model. The results show that, the flow stress decreases while the sheet metal thickness decreases when the grain size keeps constant, and the micro-sheet metal with a larger grain size is more easily to be influenced by the size effects. The material constitutive model established is validated by the stress-strain curve of the micro-sheet metal with different thicknesses derived from the tensile experiments. The rationality of the material model is verified by the fact that the calculation results are consistent with the experimental results.
基金The Key Project of National Natural Science Foun-dation of China (No50538070)
文摘Durability zonation standard (DZS) is proposed to provide useful parameters for durable concrete structure design. It deals not only with the influence of environment on structures, but also with types, functions and importance of structures based on the theory of life cycle cost(LCC). First, the basic concept of DZS for concrete structure design is defined. Then the basic principles for DZS are established. The factors for zonation according to natural environmental conditions and structural importance are identified. The usefulness of DZS by citing a real application for concrete highway bridges in Zhejiang Province is demonstrated. Finally, durability regulations are provided accordingly to zonation.
文摘China's economic growth is heavily influenced by exports, while reconciling environmental regulation and economic growth requires handling the relationship between environmental regulation and industrial competitiveness well. The effects of environmental regulation on industrial competitiveness are largely subject to the institutional design of environmental regulation. Despite numerous studies on the relationship between environmental regulation and industrial competitiveness, a consensus has yet to be reached. Aside from differences in research methodology, these studies failed to give sufficient consideration to the impact of environmental regulation on industrial competitiveness. Such effects can be negative or positive depending on the design of environmental regulatory policy. This paper has investigated the relationship between environmental regulation and the competitiveness of China's iron and steel industry and discovered that tighter environmental regulation does not diminish the competitiveness of the iron and steel industry since the policy design of environmental regulation accommodates the tolerance of advanced production capacity and includes a reasonable cost sharing mechanism. This discovery is of important reference for China to develop rational policy design to balance the relationship between environmental regulation and industrial competitiveness.
基金The Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘Traditionally governance structures are classified into "hierarchy or market" or "equity or non-equity." However,such classifications may not be effective in characterizing all governance structures of research and development(R D) alliances.Therefore,the first objective of this study is to investigate why there exist different organizational governance structures in managing R D alliances;the second objective of this study is to give strategic advice in choosing appropriate forms with respect to various characteristics of R D alliances.Through the theoretical lens that integrate both transaction cost economics(TCE) and the resource-based view(RBV),a model that focuses on six major factors is developed for determining governance structure choices,namely,technological uncertainty,cultural difference,asset specificity,technology complementarity,appropriability of the individual firm's know-how,and trust.An R D alliance with higher technological uncertainty,larger cultural differences,and greater concerns for protecting an individual's know-how is more likely to adopt non-integrated alliances as the governing structure.An R D alliance with a higher degree of asset-specificity,greater technology complementarity and greater trust among partnering organizations is more likely to adopt integrated alliances as the governing structure;an R D alliance in the face of lower technological uncertainty will tend to adopt integrated alliances.The more aligned the choice of the governance structure with its determinants,the better the R D alliance will perform,and vice versa.