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Mahutga M.C.,University of California at Riverside | Ma X.,Chinese Academy of Governance | Smith D.A.,University of Utah | Timberlake M.,University of California at Irvine
Urban Studies | Year: 2010

This paper reports results from an analysis of the relationship between the structure of the city-to-city network of global airline passenger flows and the interstate world system. While many scholars suggest that the broader parameters of the world system structure the urban hierarchy embedded within or articulated to it, others argue that the urban hierarchy is decoupling from the world system. The analyses show that there has been some modest convergence in the distribution of power in the world city system. Moreover, they suggest that the mechanism for this convergence is the upward mobility of cities located in the semi-periphery and the east Asian region. The paper closes by considering the implication of these findings for a larger understanding of the relationship between globalisation, the structure of the world city system and its articulation with the world system. © 2010 Urban Studies Journal Limited.

Wang J.,University of Science and Technology Beijing | Deng Y.,Chinese Academy of Governance | Gao Y.,University of Science and Technology Beijing
Proceedings - 2013 4th International Conference on Digital Manufacturing and Automation, ICDMA 2013 | Year: 2013

Emergency evacuation is an important means to reduce casualties in coping with emergencies. Before issuing evacuation orders, forecasting the population size is the basis of all the evacuation plans. In previous studies, researchers usually use resident population or a fixed value instead of the population size of evacuation, without considering the diversity of the number of evacuees at different times. Based on a statistical analysis of the number of people going in and out at school accommodation area, according to the changing rule of the number of evacuees at different times, this paper presents a method using conversion factors to calculate the number of evacuees in a specific area, and verifies differences in gender and education also can cause the fluctuations of the number, which provides methodological guidance for forecasting the population size in emergency evacuation. © 2013 IEEE.

Ma X.,Chinese Academy of Governance | Timberlake M.,University of Utah
Urban Studies | Year: 2013

The research constitutes the first effort to test the claim found in the world city theoretical literature that, as world cities strengthen ties with each other, their linkages with their countries' hinterlands and national urban systems will weaken. This research offers a more nuanced exploration of this hypothesis by taking into account variation in the nature of the state across countries in which world cities are located as well as the source of global capital in the world cities. Specifically, the research reported here suggests that three types of world cities-market-centred bourgeois world cities (MWC), state-centred political bureaucratic world cities (SWC) and dual-role world cities (DWC)-entail different deterritorialisation outcomes. Three countries that have prototypical global cities-Japan (SWC), China (DWC) and the US (MWC) are compared, applying longitudinal network modelling to relational data on national city networks. From 1993 to 2007, more globally connected MWCs weakened their national ties. In contrast, higher global status has no significant effect on the integration of SWCs or DWCs with their national urban systems. This indicates that the type of state, but not the source of capital, conditions whether the world city will deterritorialise vis-à-vis its national city system. © 2012 Urban Studies Journal Limited.

Liu M.,Chinese Academy of Governance | Feng T.,Lanzhou University of Technology | Smith P.,AIT Austrian Institute of Technology | Hutchison D.,Lancaster University
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2013

Computer networks, widely used by enterprises and individuals nowadays, are still vulnerable when facing traffic injection, human mistakes, malicious attacks and other failures though we spend much more time and cost on security, dependability, performability, survivability, and risk assessment to make the network provide resilient services. This is because these measures are commonly viewed as closely related but a practical means of linking them is often not achieved. Network resilience research brings together all the planning that the network can be managed at a holistic view of resilience management. This paper focuses on network resilience management from "reactive" paradigm to a "proactive" one through Situational Awareness (SA) of internal factors of network and external ones of complex, dynamic and heterogeneous network environment. After surveying the research of network resilience and resilience assessment in the network, we give a model to discuss how to construct awareness of resilience issues which includes four stages. The first step is to get the situational elements about what we are interested in. Second, to understand what happened and what is going on in the networks, pattern learning and pattern matching are exploited to identify challenge. Then, to make proactive resilience management, we need to predict challenges and look for potential ones at this stage. At the fourth stage, resilience management can help take actions of remediation and recovery according to the policy of defender and attacker. After that, the two players' behaviors of defender and attacker are modeled in the same model by using Extended Generalized Stochastic Game Nets (EGSGN) which combines Game theory into Stochastic Petri Nets. Finally, we give a case study to show how to use EGSGN to depict the network resilience situation in the same model. © 2013 Springer-Verlag.

Shao K.,University of Science and Technology Beijing | Zhai Y.,Chinese Academy of Governance | Sui H.,University of Science and Technology Beijing | Zhang C.,Wenzhou University
ICIC Express Letters | Year: 2014

Class imbalance is a very common occurrence in data mining and knowledge discovery fields where the classes in a dataset are not equally represented. Learning models based on these datasets are often unpractical just as most machine learning algorithms tend to predict the samples in the minority classes as the majority one. To better address and solve this problem, we proposed quantum-inspired evolutionary algorithm for classification in imbalanced dataset (QEA-LFID). The QEA-LFID approach employs the quantum-inspired evolutionary mechanism for selecting samples from the majority classes to alleviate the imbalance problem. Furthermore, we proposed the sample quantum gene and a fitness function built on the prediction precision of the minority and majority classes as well as the classifiers. An extensive empirical investigation involving multiple real-world datasets is performed, and comparative results show that QEA-LFID has the faster convergence rate, the stronger global optimization ability and the shorter computing time as well as the perfect performance. © 2014 ISSN 1881-803X.

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