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481.
Iraklis Giannakis Panagiotis Tsourlos Costas Papazachos George Vargemezis Antonios Giannopoulos Nikos Papadopoulos Fabio Tosti Amir Alani 《Geophysical Prospecting》2019,67(7):1948-1964
Self-potential is a passive geophysical method that can be applied in a straightforward manner with minimum requirements in the field. Nonetheless, interpretation of self-potential data is particularly challenging due to the inherited non-uniqueness present in all potential methods. Incorporating information regarding the target of interest can facilitate interpretation and increase the reliability of the final output. In the current paper, a novel method for detecting multiple sheet-like targets is presented. A numerical framework is initially described that simulates sheet-like bodies in an arbitrary 2D resistivity distribution. A scattered field formulation based on finite differences is employed that allows the edges of the sheet to be independent of the grid geometry. A novel analytical solution for two-layered models is derived and subsequently used to validate the accuracy of the proposed numerical scheme. Lastly, a hybrid optimization is proposed that couples linear least-squares with particle-swarm optimization in order to effectively locate the edges of multiple sheet-like bodies. Through numerical and real data, it is proven that the hybrid optimization overcomes local minimal that occurs in complex resistivity distributions and converges substantially faster compared to traditional particle-swarm optimization. 相似文献
482.
Effects of Dietary Protein Level on Growth and Utilization of Protein and Energy by Juvenile Mangrove Red Snapper (Lutjanus argentimaculatus ) 总被引:1,自引:1,他引:0
1Introduction The mangrove red snapper,Lutjanus argentimacu-latus(Forsskal,1775)is a carnivorous,warm-watereuryhaline fish that is considerably cultured in South-east Asia,Southern China and the Middle East(Le-ung et al.,1999;Estudillo et at.,2000;Ng et al.,2000;Catacutan et al.,2001).In Pakistan,it isknown for its good quality meat and also for its highconsumption rate.Although it fetches a premiumprice at local markets(Anonymous,2002),the in-creasing demand has generated interest towar… 相似文献
483.
China Ocean Engineering - One of the important phases of designing a craft is stability analysis and optimization of the drag force in cruise speed. In this research the longitudinal and lateral... 相似文献
484.
Alireza Kashian Abbas Rajabifard Kai-Florian Richter Yiqun Chen 《International journal of geographical information science》2019,33(7):1420-1443
In the past decade, Volunteered Geographic Information (VGI) has emerged as a new source of geographic information, making it a cheap and universal competitor to existing authoritative data sources. The growing popularity of VGI platforms, such as OpenStreetMap (OSM), would trigger malicious activities such as vandalism or spam. Similarly, wrong entries by unexperienced contributors adds to the complexities and directly impact the reliability of such databases. While there are some existing methods and tools for monitoring OSM data quality, there is still a lack of advanced mechanisms for automatic validation. This paper presents a new recommender tool which evaluates the positional plausibility of incoming POI registrations in OSM by generating near real-time validation scores. Similar to machine learning techniques, the tool discovers, stores and reapplies binary distance-based coexistence patterns between one specific POI and its surrounding objects. To clarify the idea, basic concepts about analysing coexistence patterns including design methodology and algorithms are covered in this context. Furthermore, the results of two case studies are presented to demonstrate the analytical power and reliability of the proposed technique. The encouraging results of this new recommendation tool elevates the need for developing reliable quality assurance systems in OSM and other VGI projects. 相似文献
485.
Natural Resources Research - In this work, a quantifier-guided ordered weighted averaging (OWA) method was employed for mineral potential mapping (MPM) in Nowchun Cu–Mo prospect, SE Iran. The... 相似文献
486.
Agi Augustine Junin Radzuan Abbas Azza Gbadamosi Afeez Azli Nur Bashirah 《Natural Resources Research》2020,29(2):1427-1446
Natural Resources Research - Nano-particles can localize at oil–water (O/W) interface, reduce residual oil saturation, increase the viscosity of brine and decrease the viscosity of crude oil... 相似文献
487.
摘 要:开展塔克拉玛干沙漠沙垄起伏地形夏季地表温度观测试验,旨在为塔克拉玛干沙漠环境陆面过程研究提供科学依据。2019年6月7日至9月2日在塔中地区,沿沙垄迎风坡以及背风坡底部、中部、上部、顶点及垄间谷地共设8个地表温度观测点。结果表明:(1)夏季沙垄地表温度最高温出现在垄间谷地,为74.63 ℃,最低温出现在迎风坡底部,为10.52 ℃;地表温度一天中在7:00左右达到最低,15:00左右达到最高。(2)晴天、多云以及浮尘天各观测点地表温度日均变化曲线呈单峰型,降水、扬沙及沙尘暴天呈双峰型;地表温度的最高温与日均值最大值均出现在晴天的垄间谷地,地表温度的最低温及日均值最小值均出现在降水天的迎风坡底部。(3)沙垄顶点与两个底部最大温差范围是顶点与背风坡底部在晴天的温差范围,为0~18.62 ℃,最小温差范围是顶点与迎风坡底部在降水天的温差范围,为0.01~6.18 ℃;迎风坡和背风坡在晴天地表温度温差范围最大,为0.01~16.93 ℃,在降水天温差范围最小,为0.01~4.15 ℃;顶点与两个底部夏季综合温差范围在0~18.62 ℃,迎风坡与背风坡夏季综合温差范围为0~16.93 ℃。塔克拉玛干沙漠地表温度受典型天气影响变化类型多样,沙垄顶点与底部、迎风坡与背风坡地表温度差异受风力及地形作用明显。 相似文献
488.
基于巴基斯坦不同气候区4个代表站(卡拉奇、雅各布阿巴德、奎达、德罗什)1979—2018年地面观测资料和ERA-Interim气温资料,利用一元线性回归、Mann-Kendall突变检验和Morlet小波分析,分析其气温时空变化特征。结果表明:(1)巴基斯坦过去40 a经历了先降温后增温的过程,除北部山区年平均气温增温趋势显著,四季总体都有增温,春秋两季增温趋势显著。巴基斯坦于1998年左右发生气温突变,年平均气温存在4~5、12、20~22和32 a的周期。(2)ERAInterim再分析资料与地面观测数据拟合分析显示两者相关性达到极显著水平,除北部山区外,在大部分区域误差较小,能够较好地反映巴基斯坦气温的变化特征。(3)巴基斯坦年、季平均气温空间分布地带性明显,高温区位于南部印度河平原、三角洲地区,低温区分布在北部山区,年、春季、秋季平均气温变化在空间上总体均呈现明显增长趋势. 相似文献