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711.
A new methodology for water resources multicriteria decision making under uncertainty 总被引:1,自引:0,他引:1
A multiciteria decision making problem in water resource is addressed through the generation of fuzzy Pareto optimal set. Methodology is using positive and negative ideal solutions (Lai, Y.-J., Liu, T.-Y., Hwang, C.L. (1994). TOPSIS for MODM. European Journal of Operational Research 76, 486-500) and a set of weights assigned to the objective functions in fuzzy triangular form. Solution of the problem is obtained by transforming each objective function into a set of three objective functions. A planning problem of multicriteria waste water treatment from the literature is used as an illustrative example to demonstrate the utility of the proposed methodology. The obtained fuzzy Pareto solution set has been compared with the deterministic solution set. It is shown that the proposed approach can: (a) capture the uncertainty associated with the assignment of weights; and (b) provide the decision makers with a wider range of solutions to select from. 相似文献
712.
青藏高原北缘三危山断裂晚第四纪以来的逆冲运动及其深部构造特征 总被引:1,自引:0,他引:1
三危山断裂为阿尔金断裂带东段的重要分支,位于青藏高原北缘北向扩展的前缘位置,为一条左旋走滑兼逆冲的活动断裂。通过卫片解译和野外实际调查,发现三危山主断裂穿过鸣沙山后,向西至党河水库及阳关镇附近以断层陡坎的形式出露地表。由阳关镇段向西至党河水库段,穿过鸣沙山至三危山主断裂,断层陡坎的形态由复杂变简单,落差基本集中于2~6m,但呈现逐渐减小的趋势,水平位移量也逐渐变小,反映了断裂活动强度由西向东逐渐减弱的特点。探槽和剖面解译结果显示,该段断裂错断下更新统玉门组(Qp1)砂岩和砾岩、中更新统酒泉组(Qp2)砂砾石层以及上更新统(Qp3)冲洪积砂砾石层。卫片解译、野外实地调查和深部大地电磁(MT)剖面的解译结果表明,南截山断裂向西在莫高窟南侧与三危山断裂交汇,二者在深部向阿尔金断裂收敛,上述三条断裂共同构成区域挤压性非对称半正花状构造。高原北缘的扩展是通过一系列北东-南西向走滑断裂活动及其所夹地块向北东运动和挤压实现。 相似文献
713.
714.
介绍了终止相产生的机理,及其震源计算方法—解方程组法的原理,运用该方法对厦门市数字地震台网记录的9.21集集地震的波形进行终止相识别,首次利用短周期记录终止相方法得到了9.21集集地震的破裂长度、破裂走向、破裂速度等参数,研究结果与现场考察结果基本吻合。 相似文献
715.
为了研究产生于流体力学边界层理论的混合对流方程解的性质,通过研究与混合对流方程等价的奇异积分方程正解的存在性和单调性,获得了混合对流方程凸解的存在性和凸解模的上下界,并将这些性质应用于估计混合对流方程中剪应力函数模的上下界. 相似文献
716.
利用重处理的二维地震测线对南黄海盆地北凹进行了精细的构造解释,揭示了三种不同类型的正反转构造样式,分别是中南部的逆冲型、东部的压扭型和北部的褶皱型,主要受控于其所处的不同构造位置。通过典型地震测线的平衡剖面分析,并结合区域构造动力学背景分析,认为北凹至少发生了三幕构造正反转,主要受控于不同地质时期太平洋板块对欧亚大陆俯冲速度和角度的改变。其中,三垛组沉积之后,太平洋板块俯冲角度逐步由北西向转为南西西向,并且俯冲速度明显增大,使得北凹处于北东南西向挤压环境中,广泛发育正反转构造,这也是最强烈的一幕正反转,表现为强烈的逆断层活动和地层剥蚀。过度的正反转作用可能对北凹油气藏的形成造成了不利的影响。 相似文献
717.
Seawater Intrusion in Semi-Closed Convergent Estuaries (Case Study of Moroccan Atlantic Estuaries): Application of Salinity Analytical Models 总被引:1,自引:0,他引:1
Salinity is an important parameter influencing the water quality of estuaries, and can constitute a serious problem to society due to the need for freshwater for industry and agriculture. Therefore, the determination of salt intrusion length in estuaries is a challenge for managers as well as scientists in this field. The managers tend to use simple and reliable tools for salinity variation. Although 2-D and 3-D numerical models are common tools for the prediction of salinity intrusion now, analytical models of salinity variation are much more efficient, and also require minimal sets of river data. In this paper, two analytical solutions, Brockway and Savenije used worldwide to assess longitudinal salinity variation in alluvial estuaries, are applied to the Moroccan Atlantic semi-closed estuaries, i.e., Sebou and Loukkos. The solutions are derived from salt convection-dispersion equations, with different assumptions for the dispersion coefficient. The estuaries' bathymetry is described by an exponential function. The performance of these two solutions was evaluated by comparing their results with field-measured salinity data. The Brockway model's salinity predictions performs well to observations especially in downstream reaches of the two estuaries (Sebou: R2 = 0.95, root mean square error [RMSE] = 1.50‰, normalized root mean square error [NRMSE] = 3.45‰; Loukkos: R2 = 0.95, RMSE = 1.13‰, NRMSE = 3.01‰), while the Savenije model outperformed the Brockway's model and is better to predict salt intrusion length and salinity variation along the two estuaries (Sebou: R2 = 0.97, RMSE = 1.15‰, NRMSE = 2.85‰; Loukkos: R2 = 0.98, RMSE = 0.95‰, NRMSE = 1.94‰). This revealed that both analytical solutions apply well to the estimation of salinity variation and the prediction of salt intrusion in these two estuaries. 相似文献
718.
Mountain skiing has become a popular winter ecotourism activity in China. Studying the loyalty of eco-tourists from the perspective of tourist experience is important to the continued development of mountain ski tourism. Based on the flow experience theory, we developed and tested a structural equation model to examine relationships among flow experience, positive emotions and the loyalty of eco-tourists. Survey data from 324 eco-tourists with skiing experience at Daweishan Mountain Ski Resort was used for exploratory factor, confirmatory factor and path analyses. Results revealed five dimensions of flow experiences of eco-tourists: Concentration on task at hand, Loss of self-consciousness, Transformation of time, Autotelic experience, and Challenge-skill balance. As hypothesized, influences of Transformation of time, Autotelic experience and Challenge-skill balance on positive emotions were significant and positive. Concentration on task at hand, Autotelic experience, Challenge-skill balance and positive emotions positively influenced the loyalty of eco-tourists. Suggestions for developing ecotourism products are discussed such as designing a conductive environment to activate flow experience, providing personalized service to promote positive emotion, and developing experiential tourism activities. 相似文献
719.
720.
A. J. Hale 《Geophysical Journal International》2008,174(1):391-417