No abstract

Manual monitoring of the eutrophication status of water bodies such as a dam is a challenging task. Hence, drone technology can be used in assisting the monitoring work of any water bodies. This study was conducted to develop UAV-based remote sensing to derive indicators in lake water bodies. Four sampling points were chosen for testing where the Normalized Difference Vegetation Index (NDVI) and Normalized Difference Turbidity Index (NDTI) were assessed. DJI Phantom 4 Pro drone was used for the aerial data acquisition. Ex-situ data were also acquired, such as nitrate concentration (N) and phosphate concentration (P). The hyperspectral UAV images were ortho-rectified and geo-referenced in Agisoft PhotoScan software and NDVI value estimation in ArcGIS. Results show the correlation between NDVI values and N and P concentration with coefficients values of 0.7079 for P concentration and 0.7004 for N concentration, respectively. This study confirmed the applicability of remote sensing for water resource management using UAVs, characterized as a quick and easy methodology.

The study shows a numerical analysis on bending behavior of cold-formed steel framing system and the effective cost reduction between perforated and non-perforated steel section in steel framing system. The results are presented in the form of displacement and yield moment. Using finite element analysis software, a total of 26 set of nonlinear analysis were executed to determine the effects of opening spacing, edge distance and thickness of section on bending behavior. The result shows that the increasing of the opening spacing and edge distance would increase the bending capacity. C-channel steel section showed better moment resistance in thicker section. The result was then compared to the C-channel steel section without perforation. From the analysis, it was observed that C-channel steel section without perforation had higher bending capacity than C-channel steel section with perforation in major axis. However, there is a small difference in terms of yield moment when comparing C- channel section with 0.4D of square opening and 0.3L edge opening as well as 0.1L opening space with C-channel section without perforation while reducing the volumes up to 7.28%. Thus, C-channel section with 0.4D of square opening, 0.3L edge opening and 0.1L opening space give a very effective cost reduction.

摘要:为探讨浮游植物群落对海南省小水电建设的响应,分别在海南省主要河流的上游支流已建小水电的蓄水水域与河道、规 划( 未建) 小水电河段采集浮游植物样品进行比较分析。 共鉴定出浮游植物种类 62 个属 178 种,曲壳藻( Achnanthaceae) 、异极 藻( Gomphonema) 、菱形藻( Nitzschia) 、颗粒直链藻( Melosira granulat) 、席藻( Phormidium) 、颤藻( Oscillatoria) 、小球藻( Chlorella vulgaris) 、平裂藻( Merismopedia) 、舟形藻( Navicula) 为主要的优势藻类,浮游植物丰度在 5.

A structure of cognitive unit for survivable system was proposed. Firstly, a hierarchical cognitive structure of survivable system with multilayer cognition function was established, the hierarchical cognitive structure was divided into three planes. Secondly, a cognitive unit structure based on monitor-decide-execute was put forward which has a certain degree of self-management ability, on the basis, introduced the extended cognitive unit structure. Then, a performance analyzing framework of cognitive structure was built to describe the structure and behavior of cognitive process.