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Nanlu, China

Southwest University for Nationalities often called Minzu Daxue in English, is a university located in Chengdu, the capital city of Sichuan province. Its student population is largely composed of ethnic minorities, but it has recently opened up to Han Chinese and foreigners as well. Its main campus is located in the southwestern section of the 1st ring road encircling central Chengdu. The university has two other campuses. One is located in Shuangliu county, near the airport; the Taipingyuan campus is outside the second ring road. Wikipedia.

Liu X.,Southwest University for Nationalities | Dang C.,City University of Hong Kong
IEEE Transactions on Automatic Control | Year: 2011

This technical note addresses the stability problem of delayed positive switched linear systems whose subsystems are all positive. Both discrete-time systems and continuous-time systems are studied. In our analysis, the delays in systems can be unbounded. Under certain conditions, several stability results are established by constructing a sequence of functions that are positive, monotonically decreasing, and convergent to zero as time tends to infinity (additionally continuous for continuous-time systems). It turns out that these functions can serve as an upper bound of the systems' trajectories starting from a particular region. Finally, a numerical example is presented to illustrate the obtained results. © 2011 IEEE. Source

Liang P.,Southwest University for Nationalities
Journal of Bionanoscience | Year: 2013

Information industry is booming, among which biological information as an important part in life science research is vital. However, due to its specialization, biological information sharing is lagging behind. This paper is to propose a semantic web framework for modeling a biological information knowledge base. The idea is to apply Common Warehouse Meta-model to generate a meta-model for any biological information, and then describe the meta-model by UML diagram. Instead of mapping UML diagram directly to XMI, a directed acyclic graph is extracted from the UML diagram in order to keep the semantics. The notation of the directed acyclic graph is modified with inserted annotation so that a query can be answered by searching an acyclic path in the directed acyclic graph. Eventually, the answer can be interpreted into a standard XML schema so as to be understood by machine, making a sensible statement for users. Copyright © 2013 American Scientific Publishers. All rights reserved. Source

Kou G.,University of Electronic Science and Technology of China | Ergu D.,Southwest University for Nationalities | Shi Y.,University of Electronic Science and Technology of China
Computers and Operations Research | Year: 2014

Most of the existing disaster assessment models are based on single method, such as expert system, or one of the multi-criteria decision making (MCDM) methods. This paper proposes an efficient disaster assessment expert system, which integrates fuzzy logic, survey questionnaire, Delphi method and MCDM methods. Two simulation experiments on typhoon and earthquake are introduced to validate the integrated expert system. The satisfaction degrees of the proposed model in both cases are 75% and 74.5%, respectively, which are close to the ideal rate (78%) of the proposed model. The experimental results show that the proposed expert system is not only efficient, fast and accurate, but also robust through self-adaptive study and has strong adaptability to different environments. © 2012 Elsevier Ltd. Source

Zhao X.,Bohai University | Zhao X.,China University of Petroleum - East China | Liu X.,Southwest University for Nationalities | Yin S.,Bohai University | Li H.,Bohai University
Automatica | Year: 2014

In this paper, the problems of stability for switched positive linear systems (SPLSs) under arbitrary switching are investigated in a continuous-time context. The so-called "copositive polynomial Lyapunov function" (CPLF) giving a generalization of copositive types of Lyapunov function is first proposed, which is formulated in a higher order form of the positive states of the underlying systems. It is illustrated in this paper that some classical types of Lyapunov functions can be seen as special cases of the proposed CPLF. Then, new stability conditions are developed by the new Lyapunov function approach. It is also proved that the conservativeness of the obtained criteria can be further reduced as the degree of the Lyapunov function increases. A numerical example is given to demonstrate the effectiveness and less conservativeness of the developed techniques. © 2013 Elsevier Ltd. All rights reserved. Source

Wang H.,Shanghai University | Yang S.-T.,Shanghai University | Yang S.-T.,Southwest University for Nationalities | Cao A.,Shanghai University | And 2 more authors.
Accounts of Chemical Research | Year: 2013

A diverse array of carbon nanomaterials (NMs), including fullerene, carbon nanotubes (CNTs), graphene, nanodiamonds, and carbon nanoparticles, have been discovered and widely applied in a variety of industries. Carbon NMs have been detected in the environment and have a strong possibility of entering the human body. The safety of carbon NMs has thus become a serious concern in academia and society. To achieve strict biosafety assessments, researchers need to fully understand the effects and fates of NMs in the human body, including information about absorption, distribution, metabolism, excretion, and toxicity (ADME/T).To acquire the ADME data, researchers must quantify NMs, but carbon NMs are very difficult to quantify in vivo. The carbon background in a typical biological system is high, particularly compared with the much lower concentration of carbon NMs. Moreover, carbon NMs lack a specific detection signal. Therefore, isotopic labeling, with its high sensitivity and specificity, is the first choice to quantify carbon NMs in vivo. Previously, researchers have used many isotopes, including 13C, 14C, 125I, 131I, 3H, 64Cu, 111In, 86Y, 99mTc, and 67Ga, to label carbon NMs. We used these isotopic labeling methods to study the ADME of carbon NMs via different exposure pathways in animal models.Except for the metabolism of carbon NMs, which has seldom been investigated, significant amounts of data have been reported on the in vivo absorption, distribution, excretion, and toxicity of carbon NMs, which have revealed characteristic behaviors of carbon NMs, such as reticuloendothelial system (RES) capture. However, the complexity of the biological systems and diverse preparation and functionalization of the same carbon NMs have led to inconsistent results across different studies. Therefore, the data obtained so far have not provided a compatible and systematic profile of biosafety. Further efforts are needed to address these problems.In this Account, we review the in vivo quantification methods of carbon NMs, focusing on isotopic labeling and tracing methods, and summarize the related labeling, purification, bio-sampling, and detection of carbon NMs. We also address the advantages, applicable situations, and limits of various labeling and tracing methods and propose guidelines for choosing suitable labeling methods. A collective analysis of the ADME information on various carbon NMs in vivo would provide general principles for understanding the fate of carbon NMs and the effects of chemical functionalization and aggregation of carbon NMs on their ADME/T in vivo and their implications in nanotoxicology and biosafety evaluations. © 2012 American Chemical Society. Source

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