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941.
Lijiang River is the core of Guilin's landscape. Protecting the ecological environment of Lijiang River Basin has become a national strategy. In this paper, Lijiang River Basin was used as the research area. The GF-1 multispectral image and SAR image were used as the data source. The wavelet fusion algorithm was used to fuse the GF-1 multispectral image and the SAR VV polarized backscatter image. Using random forest algorithm to construct a high-precision recognition model for GF-1 multispectral imagery, GF-1 and sentinel fusion images. The model can extract rivers, coniferous forests, broad-leaved forests, paddy fields, drylands, residential land and other land types that are closely related to the ecological environment of the Lijiang River. The results show that ①the overall accuracy based on GF-1 image classification reaches 96.15% in the 95% confidence interval, and the overall accuracy based on GF-1 and sentinel-1A backscatter coefficient reaches 94.40%. ②The classification accuracy of rivers, broad-leaved forests and drylands based on GF-1 multispectral images reached 97.74%, 93.20%, and 90.90%. They are 7.57%, 8.96%, and 1.22% higher than those based on the fused GF-1 multispectral and SAR data, respectively. The classification accuracy of the other features is similar. ③In the fusion of GF-1 multispectral and SAR data, wavelet transform was used for image fusion. It was found that the karst topography of the fusion image was prominent, which increased the difference of the features of the ground features. 相似文献
942.
We use theory and research to argue that a cultural concept of God profoundly influences female psychological development. God, as the most mythologically and historically significant transitional object, influences the developmental path of an object representation of God, the related self-representation, and the child's future relationship to a larger cultural arena of human living. We use a clinical case example to illustrate how a positive transference and an alternative concept of God mutually influence the elaboration of a God representation derived from a maternal imago, which in turn frees the patient to explore her early object representations. We close by stressing that a culture's myths and symbols, particularly the culture's God concept, have theoretical and clinical relevance in the psychological development of the individual. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
943.
本文报导了全息图拍摄时的衬底曝光,远场数和高斯光束束腰等参数对微粒场全总图再现象的对比度和分辨率的影响。讨论了适用于微粒场全息图计算机自动处理的最佳参数选择。 相似文献
944.
Helmer Strik Albert Russel Henk Van Den Heuvel Catia Cucchiarini Lou Boves 《International Journal of Speech Technology》1997,2(2):121-131
In the Netherlands there is a nationwide premium rate telephone number that can be dialed to obtain information about various forms of public transport. In 1996 this number was called more than twelve million times. Human operators managed to handle only about nine million of these calls. In order to answer more of these calls, a spoken dialog system was developed to automate part of this service. The automation component concerns information about journeys between two train stations.The starting point of our research was an existing German information system. This system was ported to Dutch. A bootstrapping method was used to collect the data, which in turn were used to improve the system itself. 相似文献
945.
946.
推导了两个倾斜平界面构成的三维展状介质空间中各个地面观测点的自激自收距离和各个界面的等效界面的计算公式。用三维快速射线追踪法计算了12个地质模型在3000m炮检距范围内共中心点道集分别在各个界面和等效界面的旅行时间,结果表明两者很接近,初步验证了三维地下空间中的等效界面定理,为三维地震勘探资料数字处理提供了理论依据. 相似文献
947.
ZnO系半导体陶瓷气敏传感器的进展 总被引:4,自引:0,他引:4
本文综述了ZnO系气敏半导体材料的发展慨况,讨论了元件的结构与气敏效应的关系,评述了解释ZnO系气敏材料性质的敏感机理,探讨了目前存在的问题及今后的发展方向。 相似文献
948.
针对具有自由曲面的机械产品的型面设计与加工,本文介绍了一个具有一定特色的CAD/CAM系统。 相似文献
949.
在江西省万安县蔗区,通过合理勤施重施氮肥和喷施植物生长调节剂,使加速繁殖的川糖79-701实现了10个月内两次采苗,最高繁殖倍数达60倍,证明霜冻蔗区也能通过“一年两采法”加速良种繁殖。 相似文献
950.
Jiang Yajun Lou Zhenliang Li Minghui 《The International Journal of Advanced Manufacturing Technology》2006,28(11-12):1071-1077
NC milling operation has become one of the main means of mold manufacturing in recent years, and the determination of milling conditions is important to assure the quality and minimize the costs of molds. This paper first constructs an optimization model of machining parameters for mold milling operations, focusing on minimizing the production costs. Then, based on the properties of the machining parameters database, it also proposes an extended model of fuzzy and rough sets theory for incomplete information systems, including incomplete continuous attribute values, and applies the model to rules learning from the machining database. Thus, by rule reasoning, the feasible solution space of optimization model can be easily established. At last, an example is presented to detail the optimization of machining parameters in the case of the cavity milling of an injection plastic mold. 相似文献