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Water resources planning based on complex system dynamics: A case study of Tianjin city 总被引:4,自引:0,他引:4
X.H. Zhang H.W. Zhang B. Chen G.Q. Chen X.H. Zhao 《Communications in Nonlinear Science & Numerical Simulation》2008,13(10):2328-2336
A complex system dynamic (SD) model focusing on water resources, termed as TianjinSD, is developed for the integrated and scientific management of the water resources of Tianjin, which contains information feedback that governs interactions in the system and is capable of synthesizing component-level knowledge into system behavior simulation at an integrated level, thus presenting reasonable predictive results for policy-making on water resources allocation and management. As for the Tianjin city, interactions among 96 components for 12 years are explored and four planning alternatives are chosen, one of which is based on the conventional mode assuming that the existing pattern of human activities will be prevailed, while the others are alternative planning designs based on the interaction of local authorities and planning researchers. Optimal mode is therefore obtained according to different scenarios when compared the simulation results for evaluation of different decisions and dynamic consequences. 相似文献
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天津地区人血六种化学元素正常值测定 总被引:2,自引:0,他引:2
何兴泉 《广东微量元素科学》1994,1(2):48-51
报道了天津地区人血液六种化学元素Cu,Zn,Fe,Ca,Ma,Mn的正常值及其测定方法,并与国内各地报道的正常值及同一地区不同单位测定的正常值进行比较,结果发现存在不同程度的差异,有的甚至过大,认为在一些问题没有解决前,最好自己测定正常值,与非健康者进行比较,才有可比性,否则,借鉴他人或其它地区的正常值会出现误差以至得出错误结论。 相似文献
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以京津风沙源区的草地为研究对象,选取中国自主B J-1、HJ数据及国外应用最为广泛的LandsatTM为数据源,结合地面同步实测草地植被覆盖度、叶面积指数和地上生物量数据,系统比较三个传感器在草地生理参数估算方面的差异与能力.研究结果表明:(1)HJ-1B与Landsat TM的红光波段与草地生理参量有更高相关性,而B J-1相对较弱,但BJ-1近红外波段在草地生理参量遥感估算上明显优于HJ-1B与Landsat TM; (2)Landsat TM的植被指数在估测草地生理参量时好于HJ-1B与BJ-1数据,HJ-1B植被指数的表现优于BJ-1;(3)相对于植被指数,全波段多元回归模型可以提升草地生理参量估测精度,基于Landsat TM与HJ-1B的提升效果微弱,而基于BJ-1数据的估算精度有明显提高,其中基于BJ-1估算叶面积指数达到了最高精度(R2 =0.61,RMSEP=0.15).总体来说,自主国产遥感数据有其自己特色,可供深入研究及推广应用的潜力很大. 相似文献
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We introduce a class of structured tensors, called generalized row strictly diagonally dominant tensors, and discuss some relationships between it and several classes of structured tensors, including nonnegative tensors, Btensors, and strictly copositive tensors. In particular, we give estimations on upper and lower bounds of solutions to the tensor complementarity problem (TCP) when the involved tensor is a generalized row strictly diagonally dominant tensor with all positive diagonal entries. The main advantage of the results obtained in this paper is that both bounds we obtained depend only on the tensor and constant vector involved in the TCP;and hence, they are very easy to calculate. 相似文献
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Evolution of cooperation in the spatial public goods game with the third-order reputation evaluation
In this letter, in order to deeply explore the role of individual reputation in the evolutionary game dynamics, we present a new third-order reputation evaluation model to discuss the evolution of cooperation in the spatial public goods game. In the current model, we should not only consider the strategy (cooperation, C or defection, D) of a focal player, but also take his own reputation and his opponent's reputation status into account. Among them, the individual reputation will be divided into being good and bad according to the specified threshold, and the good player will be endowed with the more influential strategy transfer ability, which further helps to create the clusters of cooperative and good players within the population and then fosters the cooperation. A large plethora of experimental simulation results indicate that four rules under the third-order reputation mechanism can lead to the promotion of cooperation when compared to the traditional public goods game model. The current work is conductive to a better understanding of the persistence and emergence of collective cooperation in real-world systems. 相似文献
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