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231.
232.
In the municipal solid waste (MSW) management system, there are many uncertainties associated with the coefficients and their impact factors. Uncertainties can be normally presented as both membership functions and probabilistic distributions. This study develops a scenario-based fuzzy-stochastic quadratic programming (SFQP) model for identifying an optimal MSW management policy and for allowing dual uncertainties presented as probability distributions and fuzzy sets being communicated into the optimization process. It can also reflect the dynamics of uncertainties and decision processes under a complete set of scenarios. The developed method is applied to a case study of long-term MSW management and planning. The results indicate that reasonable solutions have been generated. They are useful for identifying desired waste-flow-allocation plans and making compromises among system cost, satisfaction degree, and constraint-violation risk. 相似文献
233.
Searching for a counterfeit coin with two unreliable weighings 总被引:1,自引:0,他引:1
We provide a worst-case optimal procedure to identify one unknown heavy coin among N identically looking coins when a balance scale is used and at most two weighing results can be erroneous. The exact minimal number of weighings is determined. This solves completely the weighing problem of the case of two unreliable weighings. 相似文献
234.
235.
Hua Nie 《Journal of Mathematical Analysis and Applications》2007,334(2):889-908
This paper deals with a chemostat model with an internal inhibitor. First, the elementary stability and asymptotic behavior of solutions of the system are determined. Second, the effects of the inhibitor are considered. It turns out that the parameter μ, which measures the effect of the inhibitor, plays a very important role in deciding the stability and longtime behavior of solutions of the system. The results show that if μ is sufficiently large, this model has no coexistence solution and one of the semitrivial equilibria is a global attractor when the maximal growth rate a of the species u lies in certain range; but when a belongs to another range, all positive solutions of this model are governed by a limit problem, and two semitrivial equilibria are bistable. The main tools used here include monotone system theory, degree theory, bifurcation theory and perturbation technique. 相似文献
236.
Kebin Li Shouguo Wang Rongsheng Cheng Xijun Li Denglu Hou Xiangfu Nie Yuheng Zhang 《中国科学A辑(英文版)》1999,42(7):758-762
The ferromagnetic transition temperatures have been measured on two bathes of perovskite manganese oxides such as (La1-x
R
x
)2/3Ca1/3MnO3(R=Ce, Pr, Nd, etc.) and La2/3(Ca1-y
Cd
y
)1/3MnO3. It is found that the (La1-x
R
x
)2/3Ca1/3MnO3 samples have obviously different Curie temperatureT
C
although their (rA) (the average A-site cation radius) are almost identical, and theT
C
in the system of (La1-x
R
x
)2/3Ca1/3MnO3(R=Ce, Pr, Nd, etc.) and La2/3(Ca1-y
Cd
y
)1/3MnO3. It is found that the (La1-x
R
x
)2/3Ca1/3MnO3 compounds increases with increasingy although (rA) decreases slightly. It is suggested that the Curie temperature should be influenced by the average local A-site magnetic
moment in the ferromagnetic perovskite manganite system.
Project supported by the National Natural Science Foundation of China (Grant No. 19504012) and the Chinese Academy of Sciences. 相似文献
237.
238.
介绍了混沌理论中相空间重构技术,应用到结构损伤检测与健康监测中.以单自由度弹簧振子为例分析了基于相空间拓扑结构变化的损伤检测方法的可行性,结果表明,当弹簧的刚度降低,相空间拓扑结构发生明显变化,表明该检测方法是可行的.利用相空间重构技术,直接将结构动态响应以相空间的形式展开,根据损伤前后相空间拓扑结构的变化,提出了新的损伤因子.为了验证该方法的可行性与可靠性,进行了圆拱结构动态实验并进行损伤识别.实验结果表明,该方法能够成功地识别出圆拱结构的损伤位置及损伤程度,且灵敏度较之常用的动力指纹方法有了很大的提高.该方法只需单个测点就能计算出该点损伤因子的值,可作为结构整体参量来监测结构是否存在损伤以及结构健康状况. 相似文献
239.
Ying-Lan Jia Xiang-Yu Fan Ren-Shi Nie Quan-Hua Huang Yong-Lu Jia 《Transport in Porous Media》2013,97(2):253-279
Porous–vuggy carbonate reservoirs consist of both matrix and vug systems. This paper represents the first study of flow issues within a porous–vuggy carbonate reservoir that does not introduce a fracture system. The physical properties of matrix and vug systems are quite different in that vugs are dispersed throughout a reservoir. Assuming spherical vugs, symmetrically distributed pressure, centrifugal flow of fluids and considering media that is directly connected with wellbore as the matrix system, we established and solved a model of well testing and rate decline analysis for porous–vuggy carbonate reservoirs, which consists of a dual porosity flow behavior. Standard log–log type curves are drawn up by numerical simulation and the characteristics of type curves are analyzed thoroughly. Numerical simulations showed that concave type curves are dominated by interporosity flow factor, external boundary conditions, and are the typical response of porous–vuggy carbonate reservoirs. Field data interpretation from Tahe oilfield of China were successfully made and some useful reservoir parameters (e.g., permeability and interporosity flow factor) are obtained from well test interpretation. 相似文献
240.