The multi‐objective land allocation problem is to optimize the selection of land for different uses based on a set of decision objectives. For most applications, a geographical information system (GIS) is either absent or loosely coupled through file exchange. In this article the evolutionary algorithm (EA), a heuristic solution method for optimization problems, is integrated with a raster GIS to form a spatial decision support system (SDSS) for multi‐objective conservation reserve design. The SDSS effectively combines the functions of a GIS for data management, analysis, and visualization, with the optimization capability of the EA; and provides a uniform way to solve conservation reserve design problems with different types of constraints and objectives. The SDSS is demonstrated through application to the creation of conservation reserves in Bolivia to protect 17 endemic mammals. 相似文献
The physics behind the spectral energy distribution (SED) of blazars remains open. We assembled 36 blazars to tackle the factors that control their SED. Now, many blazar spec- tra have the "double hump" feature in the radio and far-IR frequencies. For these a parameter, , is created to characterize the behavior of the SED. We found a significant correlation be- tween the broad-line luminosity (LBLR) and . Because LBLR is an indicator of the accreting power of the source in blazars, we derived a linear correlation, ∝ M˙1/3.18, which suggests that the SED of blazars may depend on the accretion rate, like that of BL Lac objects. We also found a significant correlation between ■ and for a sample of 11 blazars (out of one of 36) with available black hole masses. This implies the Eddington accretion ratio may influence the shape of the SED of blazars. 相似文献
1INTRODUCTION In meteorological satellite cloud images, the features of Mesoscale Convective System (MCS) are shown in white bright cloud cluster, cloud band, cloud line, vorti- calcloudsystem,etc. The MCSlife cycle and spatial size usuallyvaryfrom several hours to one day and 100km to approximately 1000km, respectively. In the last two decades, it has been proven that storm and intensive con- vective weather, such as spasmodic thunderstorm and gale, tornado and short macro-precipitati… 相似文献
The relativistic beaming model is adopted to discuss quantitatively the observational differences between radio-selected BL Lac objects (RBLs) and X-ray-selected BL Lac objects (XBLs), and between BL Lac objects and flat spectrum radio quasars (FSRQs). The main results are the following:(1) In the Doppler corrected color-color(αro^in-αox^in) diagram,XBLs and FSRQs occupy separated regions, while RBLs bridge the gap between them. These properties suggest that similar intrinsic physical processes operate in all the objects under a range of intrinsic physical conditions. (2) Our results are consistent with the results of Sambruna, Maraschi and Urry (1996) from other methods. We show the αxox introduced by Sambruna to be a good index for describing the energy distribution because it represents the intrinsic energy distribution and includes the Doppler correction. (3)The Doppler effect of relativistic beaming is the main mechanism, and the physical differences(such as magnetic fields, electron energies) are also important complementary factors for understanding the relation between XBLs and RBLS. 相似文献
This paper has reported the first application of 40Ar/39 Ar dating to orthoclase from Qitianling granite. The resultant plateau ages yielded by three orthoclase specimens 2KL-17, 99LQ-2 and 2KL-31 (Note: The last one was taken from the part of granite which had been attributed to Cailing super-unit of the Indosinian Period by the former researchers) collected from the said granite are (139.57±2.79) Ma, (140.55±2.81) Ma and (144.91±2.90) Ma respectively. The above-mentioned ages represent the closed 40Ar/39 Ar age of the orthoclase. The consistency in age dating results, the similarity in geochemical characteristics and rock textures, and the NW-SE orientation of orthoclase phenocrysts almost throughout the granite, provide evidence for the intimate relationship between the Furong super-unit and the Cailing super-unit that form the main part of the granite, suggesting that they are products of comagmatic conjugate differentiation during the Late Jurassic. This paper also makes a comparison between the Qitianling granite and the Qianlishan granite.