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21.
Water resources provide the foundation for human development and environmental sustainability. Water shortage occurs more or less in some regions, which usually causes sluggish economic activities, degraded ecology, and even conflicts and disputes over water use sectors. Game theory can better reflect the behaviors of involved stakeholders and has been increasingly employed in water resources management. This paper presents a framework for the allocation of river basin water in a cooperative way. The proposed framework applies the TOPSIS model combined with the entropy weight to determine stakeholders’ initial water share, reallocating water and net benefit by using four solution concepts for crisp and fuzzy games. Finally, the Fallback bargaining model was employed to achieve unanimous agreement over the four solution concepts. The framework was demonstrated with an application to the Dongjiang River Basin, South China. The results showed that, overall, the whole basin gained more total benefits when the players participated in fuzzy coalitions rather than in crisp coalitions, and \(\left\{ {NHS_{Fuzzy} \,and\, SV_{Crisp} } \right\}\) could better distribute the total benefit of the whole basin to each player. This study tested the effectiveness of this framework for the water allocation decision-making in the context of water management in river basins. The results provide technical support for water right trade among the stakeholders at basin scale and have the potential to relieve water use conflicts of the entire basin.  相似文献   
22.
Moisture is one of the important parameters in soil polarized spectrum. It has great significance in soil remote sensing band selection and image interpretation; it also provides the information for soil investigation and analysis on physical and chemical properties. In this paper we tested and analyzed the soil polarized spectrum with different moisture in 350?~?2,500 nm wavelength, to study on the relationship between soil polarized spectral data and moisture, to determine the spectral response and changes in soil moisture, and establish models between spectral data and soil moisture. We also designed a orthogonal test on the various factors that affect soil polarized spectral characteristics, in which we studied soil moisture, polarized angle, detected angle and azimuth of the various factors and their interactions. The results showed it was most significant that the soil moisture and the interaction of soil moisture and polarized angle, followed by the interaction effect of detected angle and moisture, while the polarized angle had a little impact on the soil polarized spectrum.  相似文献   
23.
杨章 《内陆地震》1990,4(2):126-133
根据新疆及苏联天山地区的地震目录和古地震研究成果,将整个天山地区的地震韵律划分为地震世、地震亚世、地震期、地震幕、地震阶五级,探讨了各级韵律的特征。估计了我国天山地区未来地震活动趋势。  相似文献   
24.
本文搜集了现在已知的关于青藏高原地区的各种地球物理场特征,即:该区的地壳与上地幔构造,地磁场要素的分布,航空磁测的结果,古地磁极移轨迹,重力异常与均衡补偿,地热活动与温泉分布,地震活动以及深地震探测等研究结果,来探讨它与大陆板块构造的关系。 研究的初步结果表明,印度洋板块与欧亚板块交接地带的北界为雅鲁藏布江,南界为恒河平原的北缘。喜马拉雅地带为这两大板块碰撞与挤压的过渡带,其宽度约300公里左右。这一地带的大、小地震绝大部分是浅源地震,只在弧形山系和东西弧顶及其转折部位有中源地震。在这一过渡带内水热活动剧烈,重力也不均衡。 雅鲁藏布江以北到当雄一带,地壳厚度为70—73公里,喜马拉雅地区则为68—45公里左右,并向南翘起。地壳由多层介质组成,在下地壳中存在着低速层。断层面解表现为向南逆冲,主压应力轴基本上为南北向和北东向,且与震源深度相关。现在构造活动与地震活动似均逐渐向南移到主边界大断层一带。 在雅鲁藏布江以北,小震震源深度向南递加,而在恒河平原以北,则向北递加。此外,在上述两个地区均有零星的中源地震发生。因此,喜马拉雅地带的南北两侧有相向“俯冲”之势。在兴都库什地区,中源地震震源面北倾;在帕米尔地带,中源地震震源面南倾。因此,震源面构成了“V”字  相似文献   
25.
Nelson pointed out that the wave breaking criterion(H/d)_b for gentle slopes(i<1/100),inwhich H is the wave height and d is the water depth at the breaking point,is smaller than that for beachslopes of i>1/100),i.e.,the value of(H/d)_b for gentle slopes may be smaller than 0.6.Goda indicatedthat the wave breaking criterion given by himself is a result based on theoretical study,so it should be alsocorrect and can be used for gentle beaches,i.e.,the value of(H/d)_b for gentle slopes may be still largerthan 0.7.By use of high order nonlinear wave theory,this problem is analyzed in this study and the reasonwhy there is a large difference between different studies is explained.Moreover,the bottom energy loss dur-ing wave propagation is considered and the critical slope for the absence of wave breaking is also analyzed.  相似文献   
26.
冷彪  仇文革  杜诚 《岩土力学》2006,27(Z1):385-388
在隧道施工过程中,为了解开挖方量以及隧道前方的地质构造等信息,有必要对掌子面图像进行分析。传统分析中大多数以人工素描为主,效果因人而异。为了克服传统方法的局限,将图形、图像处理及三维建模技术引入对掌子面图像的处理中,建立隧道掌子面地质图像画像系统,对一系列跟踪拍摄的掌子面图像进行处理,自动提取出掌子面上不同岩层的边界,获取岩层的特征信息,以此对围岩分级。根据相邻掌子面上岩层目标的对应关系,建立起隧道的三维模型,为隧道施工提供必要的参考信息。  相似文献   
27.
It is necessary for China to establish a feasible method to verify whether an emergency evacuation plan (EEP) provides timely evacuation under the threat of flooding as a result of dam failure. Based on simulating the inundation area resulting from failure of the Huaxi Dam, this paper puts forward a quantitative approach to assess the effectiveness of an EEP by estimating the evacuation clearance times. Differences between urban and rural areas are considered, and two transportation modes are selected. Total evacuation clearance times in rural and urban areas are 135 and 80?min, respectively. Results show that total evacuation clearance times are longer than the time it takes for the flood wave to reach some communities in the area. The paper also makes some suggestions on how to decrease the total clearance time and thus enhance the effectiveness of the EEP for the Huaxi Dam.  相似文献   
28.
The objective of this study was to investigate the correlation of visibility with chemical composition of Kaohsiung aerosols. Daytime visibility was observed around noon at two observation sites in metropolitan Kaohsiung, Taiwan in the years of 1999 and 2000. Both seasonal and diurnal variation patterns of visibility were observed in the region. Ambient aerosols were sampled and analyzed for 11 constituents, including water-soluble ionic species (Cl, NO3, SO4−2, NH4+, K+, Na+, Ca+2, and Mg+2) and carbonaceous contents (OC, EC, and TC), to characterize the chemical composition of Kaohsiung aerosols. Furthermore, a stepwise multiple linear regression model was developed to elucidate the influence of aerosol species on visibility impairments. The results showed that sulfate was the dominant species that affected both light scattering coefficient and visibility. On average, the percentage contributions of visibility degrading species to light scattering coefficient were 29% for sulfate, 28% for nitrate, 22% for total carbon, and 21% for PM2.5-remainder. An empirical regression model of visibility based on sulfate, nitrate, and relative humidity was also developed. The model showed that sulfate in PM2.5 was the most sensitive species to visibility variation, suggesting that the reduction of sulfate in PM2.5 could effectively improve the visibility of metropolitan Kaohsiung. During the investigation period, an event of Asian dusts intruded metropolitan Kaohsiung and dramatically increased the aerosol loadings, especially in the coarse particles. However, local visual air quality did not degrade accordingly during the Asian dust event because both visibility and light scattering coefficient are affected mainly by the fine particles. The results are discussed in detail in the paper.  相似文献   
29.
SEED格式STEIM2数据压缩算法在实时地震数据传输中的应用   总被引:8,自引:1,他引:8  
在一定带宽内,及时、高效、无失真地传输地震数据是地震数据传输的基本要求,SEED格式给出的数据格式在数据压缩方面有其独到之处,但SEED格式没有定义数据正确性和完整性保证机制和检验方法,因而影响实时传输中的使用。本文提出一种基于SEED格式的STEIM2数据压缩算法,同EDAS数据包形式兼容的实时压缩数据包编码方法,来实现实时压缩数据的传输。经理论评估和实际数据检验,它容易实现,效率高,安全,可靠,完全可以应用于实时数据传输。  相似文献   
30.
套管井剩余油饱和度监测技术是研究剩余油分布最重要的测井方法.针对研究区块中-低孔隙度、中-低渗透率、高矿化度地层水的油藏特点与饱和度监测的现状,对比研究了现有监测技术与仪器装备的性能指标,同时考虑脉冲中子、非弹性散射与地层中元素的相互作用的特性,提出了适用于这种不同油藏地质特点的剩余油饱和度监测系列优化方案.针对某区块编制了整体监测方案,并且对监测资料进行精细处理与解释.多口井实施和应用表明,该方案与应用效果良好.  相似文献   
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