System theory,pressure-state-response and drivingpressure-state-impact-response model have been applied to establishing China's dynamic tracking evaluation system of natural resources security in this article.Base...System theory,pressure-state-response and drivingpressure-state-impact-response model have been applied to establishing China's dynamic tracking evaluation system of natural resources security in this article.Based on analytic hierarchy process and Delphi methods,the natural resources security situation has been evaluated systematically from 1991 to 2007.The result showed that the overall level of China's natural resources security presented a downtrend from 1991 to 2007.The basic reasons are the pressure indicators such as population,GDP,natural resources trade increased gradually,resulting in tension and fragility of natural resources security.展开更多
In the analysis of the system of anchoring bar and wall rock in small strain and longitudinal vibration dynamic response, the influence of the cement grouting as well as the rock layer on the anchor bar can be evaluat...In the analysis of the system of anchoring bar and wall rock in small strain and longitudinal vibration dynamic response, the influence of the cement grouting as well as the rock layer on the anchor bar can be evaluated as the two kinds of parameters: the dynamic stiffness and the damp, which are the vital reference of the anchorage quality. Based on the analytic solution to the dynamic equation of the integrated anchor bar, the new approach which combines genetic algorithm and the toolbox of Matlab is applied to solve the problem of multi-parameters reverse deduction for integrated anchorage system in dynamic testing. Using the traits of the self-organizing, self-adapting and the fast convergence speed of the genetic algorithm, the optimum of all possible solutions to dynamic parameters is obtained by calculating the project instances. Examples show that the method presented in this paper is effective and reliable.展开更多
基金supported by the National Natural Science Foundation of China(Grant nos.70873119 and 40871253)Chinese Academy of Sciences Knowledge Innovation Program(Grant no.066U0401SZ)
文摘System theory,pressure-state-response and drivingpressure-state-impact-response model have been applied to establishing China's dynamic tracking evaluation system of natural resources security in this article.Based on analytic hierarchy process and Delphi methods,the natural resources security situation has been evaluated systematically from 1991 to 2007.The result showed that the overall level of China's natural resources security presented a downtrend from 1991 to 2007.The basic reasons are the pressure indicators such as population,GDP,natural resources trade increased gradually,resulting in tension and fragility of natural resources security.
基金Funded by the Natural Science Foundation of China (50378096) and Key Technology Item of Education Ministry (03138).
文摘In the analysis of the system of anchoring bar and wall rock in small strain and longitudinal vibration dynamic response, the influence of the cement grouting as well as the rock layer on the anchor bar can be evaluated as the two kinds of parameters: the dynamic stiffness and the damp, which are the vital reference of the anchorage quality. Based on the analytic solution to the dynamic equation of the integrated anchor bar, the new approach which combines genetic algorithm and the toolbox of Matlab is applied to solve the problem of multi-parameters reverse deduction for integrated anchorage system in dynamic testing. Using the traits of the self-organizing, self-adapting and the fast convergence speed of the genetic algorithm, the optimum of all possible solutions to dynamic parameters is obtained by calculating the project instances. Examples show that the method presented in this paper is effective and reliable.
