Virtual supply chain, as a modern collaborative mode of enterprises, is important to decrease the cost and improve the efficiency and the quality of supply chains, and to satisfy customers. Based on the analysis of th...Virtual supply chain, as a modern collaborative mode of enterprises, is important to decrease the cost and improve the efficiency and the quality of supply chains, and to satisfy customers. Based on the analysis of the conception and characteristics of the virtual supply chain, the architecture of virtual supply chain is built, and corresponding objects, tasks, information and technologies are described. Three operation modes-Order-driven, manufacturer-centered, and retailer-centered are researched. As a case, virtual supply chain is applied in the electronic commerce and networked customization system of ceramic products.展开更多
Based on the definition of technology innovation of agricultural leading enterprises by domestic and foreign experts and scholars,technology innovation of agricultural enterprises is a process of new market increment,...Based on the definition of technology innovation of agricultural leading enterprises by domestic and foreign experts and scholars,technology innovation of agricultural enterprises is a process of new market increment,which uses new knowledge,technology,process and production mode,produces new products,offers new services and realizes commercialization. Characteristics of agricultural technology innovation are introduced,such as obvious regionality,relatively high risk,long-term periodicity and public attribute. Predicament for technology innovation of leading enterprises is analyzed,such as technical constraints,financial constraints and personnel constraints. Technological Innovation Mode can be classified into three modes of independent innovation,imitative innovation and cooperative innovation by the method of technology innovation. Among them,since there are some defects in the technology innovation process,independent innovation and imitative innovation are generally not used for the innovation of agricultural enterprises. Cooperative Innovation Mode can rely on foreign aid,can realize complementary advantages and achievement sharing,and can be widely applied in the agricultural innovation enterprise. Virtual organization in cooperation innovation mode is described,which makes up for technology,capital and human resources barriers in the process of agricultural enterprise innovation. Therefore,this mode is popular among the agricultural innovation enterprise.展开更多
A novel method to estimate DOA of coherent signals impinging on a uniform circular array( UCA) is presented in this paper. A virtual uniform linear array (VULA) is first derived by using spatial DFT technique, transfo...A novel method to estimate DOA of coherent signals impinging on a uniform circular array( UCA) is presented in this paper. A virtual uniform linear array (VULA) is first derived by using spatial DFT technique, transforming the UCA from element space to phase mode space to obtain the properties of ordinary ULA, and then the well known spatial smoothing technique is applied to the VULA so that the lost rank of covariance matrix due to signal coherence can be retrieved. This method makes it feasible to use the simple MUSIC algorithm to estimate DOA of coherent signals impinging on a UCA without heavy computation burden. Simulation results strongly verify the effectiveness of the algorithm.展开更多
This paper presents a scheme for realizing the frequency up-conversion between two collective atomic modes. In the scheme two atomic samples are coupled to a cavity mode. Under the large detuning condition, the two co...This paper presents a scheme for realizing the frequency up-conversion between two collective atomic modes. In the scheme two atomic samples are coupled to a cavity mode. Under the large detuning condition, the two collective atomic modes are coupled via the virtual excitation of the cavity mode and the effective Hamiltonian corresponds to the frequency up-conversion. In the scheme the cavity mode is only virtually excited and thus the process is insensitive to cavity decay.展开更多
文摘Virtual supply chain, as a modern collaborative mode of enterprises, is important to decrease the cost and improve the efficiency and the quality of supply chains, and to satisfy customers. Based on the analysis of the conception and characteristics of the virtual supply chain, the architecture of virtual supply chain is built, and corresponding objects, tasks, information and technologies are described. Three operation modes-Order-driven, manufacturer-centered, and retailer-centered are researched. As a case, virtual supply chain is applied in the electronic commerce and networked customization system of ceramic products.
基金Supported by the Social Science Planning Program of Beijing Municipal Commission of Education (SM201010020003)
文摘Based on the definition of technology innovation of agricultural leading enterprises by domestic and foreign experts and scholars,technology innovation of agricultural enterprises is a process of new market increment,which uses new knowledge,technology,process and production mode,produces new products,offers new services and realizes commercialization. Characteristics of agricultural technology innovation are introduced,such as obvious regionality,relatively high risk,long-term periodicity and public attribute. Predicament for technology innovation of leading enterprises is analyzed,such as technical constraints,financial constraints and personnel constraints. Technological Innovation Mode can be classified into three modes of independent innovation,imitative innovation and cooperative innovation by the method of technology innovation. Among them,since there are some defects in the technology innovation process,independent innovation and imitative innovation are generally not used for the innovation of agricultural enterprises. Cooperative Innovation Mode can rely on foreign aid,can realize complementary advantages and achievement sharing,and can be widely applied in the agricultural innovation enterprise. Virtual organization in cooperation innovation mode is described,which makes up for technology,capital and human resources barriers in the process of agricultural enterprise innovation. Therefore,this mode is popular among the agricultural innovation enterprise.
文摘A novel method to estimate DOA of coherent signals impinging on a uniform circular array( UCA) is presented in this paper. A virtual uniform linear array (VULA) is first derived by using spatial DFT technique, transforming the UCA from element space to phase mode space to obtain the properties of ordinary ULA, and then the well known spatial smoothing technique is applied to the VULA so that the lost rank of covariance matrix due to signal coherence can be retrieved. This method makes it feasible to use the simple MUSIC algorithm to estimate DOA of coherent signals impinging on a UCA without heavy computation burden. Simulation results strongly verify the effectiveness of the algorithm.
基金supported by the Doctoral Foundation of the Ministry of Education of China (Grant No 20070386002)
文摘This paper presents a scheme for realizing the frequency up-conversion between two collective atomic modes. In the scheme two atomic samples are coupled to a cavity mode. Under the large detuning condition, the two collective atomic modes are coupled via the virtual excitation of the cavity mode and the effective Hamiltonian corresponds to the frequency up-conversion. In the scheme the cavity mode is only virtually excited and thus the process is insensitive to cavity decay.