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This paper presents a new procedure for the optimization of the mooring design of floating platforms, in which an automatic design sequence is also established. Regarding the optimization philosophy, the following aspects are dealt with:
- • The optimization of the platform heading and its mooring pattern, taking into account the environmental force spreading;
- • optimum line length or line tension for each mooring line, associated to the optimization of the mooring line materials and sizes.
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Mateus Dantas de Paula Marta Gómez Giménez Aidin Niamir Martin Thurner Thomas Hickler 《International Journal of Digital Earth》2020,13(2):262-277
ABSTRACTGlobal, fast and accessible monitoring of biodiversity is one of the main pillars of the efforts undertaken in order to revert it loss. The Group on Earth Observations Biodiversity Observation Network (GEO-BON) provided an expert-based definition of the biological properties that should be monitored, the Essential Biodiversity Variables (EBVs). Initiatives to provide indicators for EBVs rely on global, freely available remote sensing (RS) products in combination with empirical models and field data, and are invaluable for decision making. In this study, we provide alternatives for the expansion and improvement of the EBV indicators, by suggesting current and future data from the European Space Agencýs COPERNICUS and explore the potential of RS-integrated Dynamic Global Vegetation Models (DGVMs) for the estimation of EBVs. Our review found that mainly due to the inclusion of the Sentinel constellation, Copernicus products have similar or superior potential for EBV indicator estimation in relation to their NASA counterparts. DGVMs simulate the ecosystem level EBVs (ecosystem function and structure), and when integrated with remote sensing data have great potential to not only offer improved estimation of current states but to provide projection of ecosystem impacts. We suggest that focus on producing EBV relevant outputs should be a priority within the research community, to support biodiversity preservation efforts. 相似文献
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Forest soil is an important component of the natural environment, and is a primary medium for many biological activities. In this study, soil loss and displacement by excavator and bulldozer （heavy equipments） were measured on cut and fills slopes of forest roads located in Mazandaran province, lran. The volumes of soil losses were estimated by prismoidal analyses of cut and fill slopes deformation between two time treatments （under subgrading and two years later） in slope classes of 30-50% and 50-70%. Weights of soil losses were calculated by multiplying the volumes of soil losses （cm^3） to the general bulk density （1.3g/cm^3）. Soil displaced area by heavy equipment was evaluated according to earth working width. Results indicated that heavy equipment has significant effect on deformation of cut slope gradient and fill slope length （p〈0.0001）. During the two-year period, the cut （p〈0.0002） and fill （p〈0.0001） slope gradients were significantly deformed in different slope classes. The average soil loss by excavator and bulldozer were 160.35 t/ha·yr and 429.09 t/ha·yr, respectively. Moreover, the soil displaced area during the subgrading process by bulldozer was greater than excavator in both two slope classes （p〈0.05）. Soil loss and displacement in forest roads can be rednced by applying powerful excavators in subgrading project, especially in steep terrains. 相似文献
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Prediction of the soil erosion in a forest and sediment yield from road network through GIS and SEDMODL 总被引：3，自引：0，他引：3
This study was conducted to classify water erosion risk for a deciduous forest and to predict the amount of sediment yield from forest road network. GIS in combination with AHP was used for determining the soil erosion risk degrees of forest. Beside, sediment yield from forest roads with gravel and asphalted surfacing was estimated using SEDMODL. Rainfall simulator was used in calibration and validation process of model. Results showed that 47.9% of forest soil is classified from moderate to very high vulnerability. 32.3% of roads were located in soil erosion risk class of very high. This class is generally found in the eastern region of forest, while areas with very low risk are found in the south western part. 14.6% of the forest roads were ranked as having very low sediment yield. Only 61 segments out of 339 segments of forest road network delivered sediment to the ravine network. The estimated annual sediment yield for all of road sections by SEDMODL and rainfall simulator were 10,935.45 and 10,509.29 g m-2, respectively. Results of the calibration and validation process showed that the variation accounted for in the predicted values by SEDMODL with the observed values under rainfall simulation was 3.90%. Best management practices （BMP） must be considered for the areas with high degrees of erosion risk. 相似文献
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