Based on related theories on the evaluation of city plan implementation and the empirical study on Caoyang-Xincun, a residential quarter in Shanghai, the paper explores the community plan implementation from the persp...Based on related theories on the evaluation of city plan implementation and the empirical study on Caoyang-Xincun, a residential quarter in Shanghai, the paper explores the community plan implementation from the perspective of public space. And with the differences and conformities between the plan's blueprint and the reality as the breakthrough point, the paper points out that in terms of differences, the implementation of the Caoyang-Xincun plan has neglected the construction of public space, which influenced the general quality of public life of the residents, while in terms of conformities, the implementation of the plan has produced a positive impact on current public life in the community.展开更多
Multi-commodity flow problems（MCFs） can be found in many areas, such as transportation, communication, and logistics. Therefore, such problems have been studied by a multitude of researchers, and a variety of method...Multi-commodity flow problems（MCFs） can be found in many areas, such as transportation, communication, and logistics. Therefore, such problems have been studied by a multitude of researchers, and a variety of methods have been proposed for solving it. However, most researchers only discuss the properties of different models and algorithms without taking into account the impacts of actual implementation. In fact, the true performance of a method may differ greatly across various implementations. In this paper, several popular optimization solvers for implementations of column generation and Lagrangian relaxation are discussed. In order to test scalability and optimality, three groups of networks with different structures are used as case studies. Results show that column generation outperforms Lagrangian relaxation in most instances, but the latter is better suited to networks with a large number of commodities.展开更多
基金the National Natural Sciences Fundation on "Studies on Urban Planning Implementation Evaluation and Methods" No. 51178315
文摘Based on related theories on the evaluation of city plan implementation and the empirical study on Caoyang-Xincun, a residential quarter in Shanghai, the paper explores the community plan implementation from the perspective of public space. And with the differences and conformities between the plan's blueprint and the reality as the breakthrough point, the paper points out that in terms of differences, the implementation of the Caoyang-Xincun plan has neglected the construction of public space, which influenced the general quality of public life of the residents, while in terms of conformities, the implementation of the plan has produced a positive impact on current public life in the community.
基金supported by research funds from the National Natural Science Foundation of China (Nos. 61521091, 61650110516, 61601013)
文摘Multi-commodity flow problems（MCFs） can be found in many areas, such as transportation, communication, and logistics. Therefore, such problems have been studied by a multitude of researchers, and a variety of methods have been proposed for solving it. However, most researchers only discuss the properties of different models and algorithms without taking into account the impacts of actual implementation. In fact, the true performance of a method may differ greatly across various implementations. In this paper, several popular optimization solvers for implementations of column generation and Lagrangian relaxation are discussed. In order to test scalability and optimality, three groups of networks with different structures are used as case studies. Results show that column generation outperforms Lagrangian relaxation in most instances, but the latter is better suited to networks with a large number of commodities.
