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In multiobjective optimization, trade-off analysis plays an important role in determining most preferred solution. This paper presents an explicit interactive trade-off analysis based on the surrogate worth trade-off function to determine the best compromised solution. In the multiobjective framework thermal power dispatch problem is undertaken in which four objectives viz. cost, NOx emission, SOx emission and COx emission are minimized simultaneously. The interactive process is implemented using a weighting method by regulating the relative weights of objectives in systematic manner. Hence the weighting method facilitates to simulate the trade-offrelation between the conflicting objectives in non-inferior domain. Exploiting fuzzy decision making theory to access the indifference band, interaction with the decision maker is obtained via surrogate worth trade-off (SWT) functions of the objectives. The surrogate worth trade-off functions are constructed in the functional space and then transformed into the decision space, so the surrogate worth trade-off functions of objectives relate the decision maker's preferences to non-inferior solutions through optimal weight patterns. The optimal solution of thermal power dispatch problem is obtained by considering real and reactive power losses. Decoupled load flow analysis is performed to find the transmission losses. The validity of the proposed method is demonstrated on 11-bus, 17-lines IEEE system, comprising of three generators. 相似文献
333.
Evidence from three-dimensional seismic reflectivity images for enhanced melt supply beneath mid-ocean-ridge discontinuities 总被引:1,自引:0,他引:1
Kent GM Singh SC Harding AJ Sinha MC Orcutt JA Barton PJ White RS Bazin S Hobbs RW Tong CH Pye JW 《Nature》2000,406(6796):614-618
Quantifying the melt distribution and crustal structure across ridge-axis discontinuities is essential for understanding the relationship between magmatic, tectonic and petrologic segmentation of mid-ocean-ridge spreading centres. The geometry and continuity of magma bodies beneath features such as overlapping spreading centres can strongly influence the composition of erupted lavas and may give insight into the underlying pattern of mantle flow. Here we present three-dimensional images of seismic reflectivity beneath a mid-ocean ridge to investigate the nature of melt distribution across a ridge-axis discontinuity. Reflectivity slices through the 9 degrees 03' N overlapping spreading centre on East Pacific Rise suggest that it has a robust magma supply, with melt bodies underlying both limbs and ponding of melt beneath large areas of the overlap basin. The geometry of melt distribution beneath this offset is inconsistent with large-scale, crustal redistribution of melt away from centres of upwelling. The complex distribution of melt seems instead to be caused by a combination of vertical melt transport from the underlying mantle and subsequent focusing of melt beneath a magma freezing boundary in the mid-crust. 相似文献
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在1440-1530 ℃,通过X射线装置观测了石墨还原CaO-SiO2-Al2O3-FeO熔渣(CaO/SiO2=0.75-1.5)中FeO反应过程中渣的起泡行为,测定了熔渣的起泡指数和起泡率等参数。结果表明,熔渣的起泡率随熔渣中FeO的初己考叭墼疃鹊纳叨龃蟆? 相似文献