A key problem of electronic commerce (for short e-commerce) is fair exchange which guarantees that at the end of the transaction, either both parties involved in the trausaction receive each other's items or none d...A key problem of electronic commerce (for short e-commerce) is fair exchange which guarantees that at the end of the transaction, either both parties involved in the trausaction receive each other's items or none do. A non-interactive optimistic fair exchange e-commerce protocol model based on the publicly verifiable secret sharing is presented. The main idea of our exchange protocol is to interchange verifiable and recoverable keys of the symmetric encryption for participants' items. So it is especially suitable for exchange of large-size items. Furthermore, our protocol is efficient and simple as it does not need interactive proof system which has been adopted by a large quantity of previously proposed fair exchange protocols. Based on a modified (2,2) secret sharing scheme, a concrete non-interactive fair exchange e-commerce protocol is designed.展开更多
The traditional manner to design public transportation system is to sequentially design the transit network and public bicycle network. A new public transportation system design problem that simultaneously considers b...The traditional manner to design public transportation system is to sequentially design the transit network and public bicycle network. A new public transportation system design problem that simultaneously considers both bus network design and public bicycle network design is proposed. The chemical reaction optimization(CRO) is designed to solve the problem. A shortcoming of CRO is that, when the two-molecule collisions take place, the molecules are randomly picked from the container.Hence, we improve CRO by employing different mating strategies. The computational results confirm the benefits of the mating strategies. Numerical experiments are conducted on the Sioux-Falls network. A comparison with the traditional sequential modeling framework indicates that the proposed approach has a better performance and is more robust. The practical applicability of the approach is proved by employing a real size network.展开更多
The text aims to investigate the relevance of the concept of"public space" and the continuous variations which have changed its meaning. Going beyond the concept of public space, the author can understand the semant...The text aims to investigate the relevance of the concept of"public space" and the continuous variations which have changed its meaning. Going beyond the concept of public space, the author can understand the semantic boundaries of this definition: Today, relational spaces and shared spaces are the forms with which people can express the concept of public space. The gradual spread of new forms of communication has transformed the static view of public space in a more dynamic condition, the distinction between square, street, garden has lost its meaning leaving space to fragments and residues. Contemporary public spaces are defined, as the residual places that come from the abandonment of industries. The large mono-functional voids, which originate from industrial dismantlement, should be strategically reconsidered as new shared public spaces, where the integration between different functions leads to reactivate new forms of re-using of built space.展开更多
While dramatists Tang Xianzu and William Shakespeare lived and worked on two different continents,they shared a literary legacy.As this year marks the 400th year since their passing,a series of cultural events are bei...While dramatists Tang Xianzu and William Shakespeare lived and worked on two different continents,they shared a literary legacy.As this year marks the 400th year since their passing,a series of cultural events are being held to commemorate the literary masters.展开更多
基金This project was partially supported by the National Natural Science Foundation of China (60273049, 90104005).
文摘A key problem of electronic commerce (for short e-commerce) is fair exchange which guarantees that at the end of the transaction, either both parties involved in the trausaction receive each other's items or none do. A non-interactive optimistic fair exchange e-commerce protocol model based on the publicly verifiable secret sharing is presented. The main idea of our exchange protocol is to interchange verifiable and recoverable keys of the symmetric encryption for participants' items. So it is especially suitable for exchange of large-size items. Furthermore, our protocol is efficient and simple as it does not need interactive proof system which has been adopted by a large quantity of previously proposed fair exchange protocols. Based on a modified (2,2) secret sharing scheme, a concrete non-interactive fair exchange e-commerce protocol is designed.
基金Projects(71301115,71271150,71101102)supported by the National Natural Science Foundation of ChinaProject(20130032120009)supported by Specialized Research Fund for the Doctoral Program of Higher Education of China
文摘The traditional manner to design public transportation system is to sequentially design the transit network and public bicycle network. A new public transportation system design problem that simultaneously considers both bus network design and public bicycle network design is proposed. The chemical reaction optimization(CRO) is designed to solve the problem. A shortcoming of CRO is that, when the two-molecule collisions take place, the molecules are randomly picked from the container.Hence, we improve CRO by employing different mating strategies. The computational results confirm the benefits of the mating strategies. Numerical experiments are conducted on the Sioux-Falls network. A comparison with the traditional sequential modeling framework indicates that the proposed approach has a better performance and is more robust. The practical applicability of the approach is proved by employing a real size network.
文摘The text aims to investigate the relevance of the concept of"public space" and the continuous variations which have changed its meaning. Going beyond the concept of public space, the author can understand the semantic boundaries of this definition: Today, relational spaces and shared spaces are the forms with which people can express the concept of public space. The gradual spread of new forms of communication has transformed the static view of public space in a more dynamic condition, the distinction between square, street, garden has lost its meaning leaving space to fragments and residues. Contemporary public spaces are defined, as the residual places that come from the abandonment of industries. The large mono-functional voids, which originate from industrial dismantlement, should be strategically reconsidered as new shared public spaces, where the integration between different functions leads to reactivate new forms of re-using of built space.
文摘While dramatists Tang Xianzu and William Shakespeare lived and worked on two different continents,they shared a literary legacy.As this year marks the 400th year since their passing,a series of cultural events are being held to commemorate the literary masters.