Research on basic characteristics of complex system brittleness

The goal of this paper is to research one new characteristic of complex system. Brittleness, which is one new characteritic of complex system, is presented in this paper. The linguistic and qualitative descriptions of complex system are also given in this paper. Otherwise, the qualitative description of complex system is presented at first. On the basis of analyzing the existing brittleness problems, linguistic description and mathematic description of brittleness are given as well. Three kinds of phenomena to judge brittleness of complex system are also given, based on catastrophe theory. Basic characteristics of brittleness are given on the basis of its mathematic description. Two critical point sets are defined by using catastrophe theory. The definition of brittleness and its related theory can serve the control of complex system, and provide theoretical basis for the design and control of complex system.

Brittleness research on complex system based on brittle link entropy

As the scale of complex system is growing larger and larger, interferences from internal and outer system can result in the collapse of one subsystem in a complex system. They will not only make one subsystem collapse but also influence the other subsystems. Moreover, the whole complex system can collapse consequently. The mechanism of collapse of complex system is clue to the brittleness of complex system that is presented and argued as the basic characteristic in this paper. It is the brittleness link entropy between subsystems that leads to the collapse of whole system. Effective ways that can be adopted to reduce the brittleness entropy can see the successful control of brittleness.

Research Framework for Ecosystem Vulnerability:Measurement, Prediction, and Risk Assessment

The fragility of ecosystem health has become a key factor hindering the sustainable development of the ecological environment. Through a review of published research from domestic and foreign scholars, starting from the endogenous logic of studies in the field of ecosystem vulnerability(EV), this paper sorts out the literature on the aspects of measurement models, prediction methods and risk assessment, comprehensively defines the research category and scientific framework of EV, and analyzes the research ideas and development trends. We arrived at the following conclusions: 1) The connotation of ecosystem vulnerability not only embodies the change in the vulnerability of the natural environment, but it also reflects the irreversible damage to the ecosystem caused by excessive development and industrial production activities. 2) The setting of ecosystem vulnerability indices should aim to fully reflect the essential features of that vulnerability, which should include the index systems of natural, social, economic and other related factors. 3) There are many types of ecosystem vulnerability measurement methods, prediction models and risk evaluation models, which have different focuses and advantages. The most appropriate method should be adopted for conducting comprehensive and systematic evaluation, prediction and estimation according to the different representation and evolution mechanisms of the chosen research object and regional ecosystem vulnerability. 4) Based on the regional system characteristics, corresponding risk management measures should be proposed, and pertinent policy suggestions should be put forward to improve the ecological safety and sustainable development of an ecologically vulnerable area.