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Optimizing Bucket Elevator Performance through a Blend of Discrete Element Method, Response Surface Methodology, and Firefly Algorithm Approaches
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作者 Pirapat Arunyanart Nithitorn Kongkaew Supattarachai Sudsawat 《Computers, Materials & Continua》 SCIE EI 2024年第8期3379-3403,共25页
This research introduces a novel approach to enhancing bucket elevator design and operation through the integration of discrete element method(DEM)simulation,design of experiments(DOE),and metaheuristic optimization a... This research introduces a novel approach to enhancing bucket elevator design and operation through the integration of discrete element method(DEM)simulation,design of experiments(DOE),and metaheuristic optimization algorithms.Specifically,the study employs the firefly algorithm(FA),a metaheuristic optimization technique,to optimize bucket elevator parameters for maximizing transport mass and mass flow rate discharge of granular materials under specified working conditions.The experimental methodology involves several key steps:screening experiments to identify significant factors affecting bucket elevator operation,central composite design(CCD)experiments to further explore these factors,and response surface methodology(RSM)to create predictive models for transport mass and mass flow rate discharge.The FA algorithm is then applied to optimize these models,and the results are validated through simulation and empirical experiments.The study validates the optimized parameters through simulation and empirical experiments,comparing results with DEM simulation.The outcomes demonstrate the effectiveness of the FA algorithm in identifying optimal bucket parameters,showcasing less than 10%and 15%deviation for transport mass and mass flow rate discharge,respectively,between predicted and actual values.Overall,this research provides insights into the critical factors influencing bucket elevator operation and offers a systematic methodology for optimizing bucket parameters,contributing to more efficient material handling in various industrial applications. 展开更多
关键词 Discrete element method(dem) design of experiments(DOE) firefly algorithm(FA) response surface methodology(RSM)
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Interpolation Technique for the Underwater DEM Generated by an Unmanned Surface Vessel
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作者 Shiwei Qin Zili Dai 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第9期3157-3172,共16页
High-resolution underwater digital elevation models(DEMs)are important for water and soil conservation,hydrological analysis,and river channel dredging.In this work,the underwater topography of the Panjing River in Sh... High-resolution underwater digital elevation models(DEMs)are important for water and soil conservation,hydrological analysis,and river channel dredging.In this work,the underwater topography of the Panjing River in Shanghai,China,was measured by an unmanned surface vessel.Five different interpolation methods were used to generate the underwater DEM and their precision and applicability for different underwater landforms were analyzed through cross-validation.The results showed that there was a positive correlation between the interpolation error and the terrain surface roughness.The five interpolation methods were all appropriate for the survey area,but their accuracy varied with different surface roughness.Based on the analysis results,an integrated approach was proposed to automatically select the appropriate interpolation method according to the different surface roughness in the surveying area.This approach improved the overall interpolation precision.The suggested technique provides a reference for the selection of interpolationmethods for underwater DEMdata. 展开更多
关键词 Underwater dem interpolation technique unmanned surface vessel surface roughness
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DEM Numerical Simulation of Abrasive Wear Characteristics of a Bioinspired Ridged Surface 被引量:10
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作者 Mohammad Almagzoub Mohammad Carlo Menon 《Journal of Bionic Engineering》 SCIE EI CSCD 2010年第2期175-181,共7页
This paper presents numerical investigations into a ridged surface whose design is inspired by the geometry of a Farrer’sscallop.The objective of the performed research is to assess if the proposed Bioinspired Ridged... This paper presents numerical investigations into a ridged surface whose design is inspired by the geometry of a Farrer’sscallop.The objective of the performed research is to assess if the proposed Bioinspired Ridged Surface (BRS) can potentiallyimprove wear resistance of soil-engaging components used in agricultural machinery and to validate numerical simulationsperformed using software based on the Discrete Element Method (DEM).The wear performance of the BRS is experimentallydetermined and also compared with a conventional flat surface.Different size of soil particles and relative velocities between theabrasive sand and the testing surfaces are used.Comparative results show that the numerical simulations are in agreement withthe experimental results and support the hypothesis that abrasive wear is greatly reduced by substituting a conventional flatsurface with the BRS. 展开更多
关键词 bioinspired ridged surface abrasive wear numerical simulation Discrete Element Method (dem)
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Study on extracting method of single slope surface shape based on DEM:taking Wanzhou district of three gorges reservoir area as example 被引量:1
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作者 ZHOU Qi-gang YUAN Li-feng 《重庆邮电大学学报(自然科学版)》 2007年第3期276-280,共5页
This paper focused on the extracting method of single slope shape. Applying the software of ARCGIS 9.0, DEM (digital elevation model) was established. From the DEM, topographic characters, including valleys and ridges... This paper focused on the extracting method of single slope shape. Applying the software of ARCGIS 9.0, DEM (digital elevation model) was established. From the DEM, topographic characters, including valleys and ridges were extracted. Some valley lines were extended in order to intersect with the ridges nearby. All slope were divided into different slope surface, which enclosed by valleys and ridges. And the slope surface shapes were defined three types, Line Slope, Upper-concave and lower-convex slope, Upper-convex and lower-concave slope, according to their functions. And the judge formula of single slope surface shape was brought forward. Taking Wanzhou District as test area, it indicates that auto-extracting method of single slope surface shape has high precision relatively. This study can provide references to the studies of region geological disasters prevention and cure. 展开更多
关键词 斜坡表面形状 提取 地理信息系统 数字视图模型
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Application of DEM overlaying technique in surface subsidence identification─a case study in Ruqigou coal mining area of Ningxia,China
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作者 CHEN Li-ding(Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences,Beijing 100085, China) 《Journal of Geographical Sciences》 SCIE CSCD 1999年第1期43-50,共8页
Subsidence occurred in many parts of the world. particularly in densely populated deltaic regions, causing extremely expensive damage. It can be resulted from natural causes. man-made induced causes, or other mixed ca... Subsidence occurred in many parts of the world. particularly in densely populated deltaic regions, causing extremely expensive damage. It can be resulted from natural causes. man-made induced causes, or other mixed causes. For identifying surface subsidence, many techniques have been employed, for example, geodetic monitoring, airborne laser subsidence measurement system,differential S.A.R., interferometry DGPS, and satellite radar measurements. However. all these methods require large time span and a large amount of field work. With the development of GIS techniques, identification of surface subsidence is becoming a relative easy problem. Ruqigou coal mining area was selected as a case study to identify the surface subsidence with DEM (digital elevation model) overlaying techniques. The result shows that DEM overlaying technique is a very useful method on surface subsidence identification. The accuracy of the results are largely dependent on the precision of the data-input. 展开更多
关键词 surface subsidence Rubsidence coal mining area GIS dem overlaying technique
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Automatic Correction of DEM Surface Errors
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作者 Ahmed F. Elaksher 《Journal of Geographic Information System》 2017年第3期326-338,共13页
The automation of extracting planner surfaces is a main field of research in digital photogrammetry. These surfaces are essential to generate three dimensional GIS databases. Surfaces are usually determined from eithe... The automation of extracting planner surfaces is a main field of research in digital photogrammetry. These surfaces are essential to generate three dimensional GIS databases. Surfaces are usually determined from either DEMs or images. Each dataset provides a different type of information. Thus, the combination of the two datasets should enhance the surface reconstruction process. This paper presents a new technique for generating 3D surfaces by combining both correlation-based DEMs and aerial images. The process starts by discriminating DEM points that represent planner surfaces using local statistics of neighboring elevations and intensities and point elevations. A segmented orthophoto is then used to group these points into different regions. The elevations of the points in each region are fed into a least squares adjustment model to compute the best-fit planner surface parameters. Refinement of surface borders is then performed using a region growing algorithm. The RMSE for five test sites showed a spatial accuracy of 5 - 8 cm. 展开更多
关键词 PHOTOGRAMMETRY dem ORTHOPHOTO PLANNER surfaceS
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Reconstructing DEM using TLS point cloud data and NURBS surface 被引量:2
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作者 宋冰 郑南山 +2 位作者 厉东伟 陈冉丽 李亮 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第9期3165-3172,共8页
Underground coal mining inevitably results in land surface subsidence.Acquiring information on land surface subsidence is important in the detection of surface change.However,conventional data acquisition techniques c... Underground coal mining inevitably results in land surface subsidence.Acquiring information on land surface subsidence is important in the detection of surface change.However,conventional data acquisition techniques cannot always retrieve information on whole subsidence area.This study focuses on the reconstruction of a digital elevation model(DEM) with terrestrial laser scanning(TLS) point cloud data.Firstly,the methodology of the DEM with terrestrial 3-dimensional laser scanning is introduced.Then,a DEM modeling approach that involves the application of curved non-uniform rational B-splines(NURBS) surface is put forward.Finally,the performance of the DEM modeling approach with different surface inverse methods is demonstrated.The results indicate that the DEM based on the point cloud data and curved NURBS surface can achieve satisfactory accuracy.In addition,the performance of the hyperbolic paraboloid appears to be better than that of the elliptic paraboloid.The reconstructed DEM is continuous and can easily be integrated into other programs.Such features are of great importance in monitoring dynamic ground surface subsidence. 展开更多
关键词 terrestrial 3D laser scanning NURBS surface dem modeling performance analysis
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Application of High-Resolution Remote Sensing Technology in Quantitative Study on Coseismic Surface Rupture Zones: An Example of the 2008 M_w7.2 Yutian Earthquake
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作者 SHAN Xinjian HAN Nana +3 位作者 SONG Xiaogang GONG Wenyu QU Chunyan ZHANG Yingfeng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2018年第6期2468-2469,共2页
Objective Nowadays, high-resolution remote sensing technology has brought new changes to surveys of earthquakes, and the quantitative study of seismic faults based on this technology has become a trend in the world(Ba... Objective Nowadays, high-resolution remote sensing technology has brought new changes to surveys of earthquakes, and the quantitative study of seismic faults based on this technology has become a trend in the world(Barzegari et al., 2017). An Mw 7.2 earthquake occurred in Yutian of Xinjiang on the western end of the Altyn Tagh fault on March 21 st, 2008. It is difficult to access this depopulated zone because of the high altitude and only 1–2 months of snowmelt. This study utilized high-resolution 展开更多
关键词 dem Application of High-Resolution Remote Sensing Technology in Quantitative Study on Coseismic surface Rupture Zones An Example of the 2008 M_w7.2 Yutian Earthquake
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Method for Improving Digital Elevation Model Precision of Consumer Level Unmanned Aerial Vehicles
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作者 Qiuxin XIA Zhong LI +2 位作者 Yong ZHOU Ensi ZHANG Gang YANG 《Meteorological and Environmental Research》 2024年第2期71-77,共7页
Currently,the aerial survey system of low-altitude unmanned aerial vehicles(UAVs)has been widely used in acquiring digital map 4D products,mapping,digital linear maps,and other aspects.However,there are problems,such ... Currently,the aerial survey system of low-altitude unmanned aerial vehicles(UAVs)has been widely used in acquiring digital map 4D products,mapping,digital linear maps,and other aspects.However,there are problems,such as low precision and weak practicability in constructing digital elevation model(DEM)products through the data collected using consumption level UAVs.Therefore,improving the accuracy of DEM products obtained by consumption level UAVs is a crucial and complex issue in the research of UAV aerial survey systems.In precision elevation measurement,the geodetic height of a certain number of ground points with reasonable distribution in the region is often obtained first.Then,the normal height of the ground points is obtained by leveling,and the elevation residual value surface of the region is fitted.Finally,the normal height of the points to be solved in the region is obtained by fitting the elevation residual surface.Therefore,the elevation residual fitting method was used to improve the accuracy of consumer UAV DEM products in this study.First,a high-quality ground point cloud was obtained by constructing the gradient filtering-cloth simulation filtering(GF-CSF)model.Second,an abnormal elevation fitting residual DEM model was constructed.Lastly,the final DEM was obtained using the DEM difference method.The experimental results show that among the 20 random sampling inspection points,the average elevation residual was 2.3 mm,and the root mean square error(RMSE)was 16.7 mm after the DEM accuracy was improved by the method.The average elevation residual without improving the DEM accuracy was 28.6 mm,and RMSE was 33.7 mm. 展开更多
关键词 UAV aerial survey GF CSF dem surface fitting
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A Study on the Physical Properties of Banana Straw Based on the Discrete Element Method
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作者 Sen Zhang Jie Jiang Yuedong Wang 《Fluid Dynamics & Materials Processing》 EI 2023年第5期1159-1172,共14页
To improve the application of discrete element models(DEM)to the design of agricultural crushers,in this study a new highly accurate model is elaborated.The model takes into account the fiber structure,porous nature o... To improve the application of discrete element models(DEM)to the design of agricultural crushers,in this study a new highly accurate model is elaborated.The model takes into account the fiber structure,porous nature of the material and the leaf sheath coating structure.Dedicated experimental tests are conducted to determine the required“intrinsic”and basic contact parameters of the considered banana straw materials.A large number of bonding parameters are examined in relation to the particle aggregation model in order to characterize different actual banana straws.Using the particle surface energy contact model,the viscosity characteristics of the crushed material are determined together with the related stacking angle(considered as the main response factor).Through single factor experiment analysis,it is found that when the surface energy is 0.9 J·m-2,the relative error between simulations and physical experiments is 5.288%. 展开更多
关键词 Banana straw discrete element model contact model surface energy dem
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Impact of land cover change on land surface temperature: A case study of Spiti Valley 被引量:3
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作者 KUMAR Pankaj HUSAIN Arif +1 位作者 SINGH Ram Babu KUMAR Manish 《Journal of Mountain Science》 SCIE CSCD 2018年第8期1658-1670,共13页
Land surface temperature(LST) is the skin temperature of the earth surface. LST depends on the amount of sunlight received by any geographical area. Apart from sun light, LST is also affected by the land cover, which ... Land surface temperature(LST) is the skin temperature of the earth surface. LST depends on the amount of sunlight received by any geographical area. Apart from sun light, LST is also affected by the land cover, which leads to change in land surface temperature. Impact of land cover change(LCC) on LST has been assessed using Landsat TM5, Landsat 8 TIRS/OLI and Digital Elevation Model(ASTER) for Spiti Valley, Himachal Pradesh, India. In the present study, Spiti valley was divided into three altitudinal zones to check the pattern of changing land cover along different altitudes and LST was calculated for all the four land cover categories extracted from remote sensing data for the years of 1990 and 2015. Matrix table was used as a technique to evaluate the land cover change between two different years. Matrix table shows that as a whole, about 2,151,647 ha(30%) area of Spiti valley experienced change in land cover in the last 25 years. The result also shows vegetation and water bodies increased by 107,560.2 ha(605.87%) and 45 ha(0.98%), respectively. Snow cover and barren land decreased by 19,016.5 ha(23.92%) and 88,589(14.14%), during the study period. A significant increase has been noticed in vegetation amongst all land cover types. Minimum, maximum and mean LST for three altitudinal zones have been calculated. The mean LST recorded was 11℃ in 1990 but it rose by 2℃ and reached to 13℃ in 2015. Changes in LST were obtained for each land cover categories. The mean temperature of different land cover types was calculated by averaging value of all pixels of a given land cover types. The mean LST of vegetation, barren land, snow cover and water body increased by 6℃, 9℃, 1℃, and 7℃, respectively. Further, relationships between LST, Normalized Difference Snow Index(NDSI), and Normalised Difference Vegetation Index(NDVI) were established using Linear Regression. 展开更多
关键词 Land surface temperature Land cover change Normalised difference snow index Normalised Difference Vegetation Index dem Remote Sensing GIS Linear Regression
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Estimation of Ground Deformation Caused by the Earthquake (M7.2) in Japan,2008,from the Geomorphic Image Analysis of High Resolution LiDAR DEMs 被引量:2
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作者 MUKOYAMA Sakae 《Journal of Mountain Science》 SCIE CSCD 2011年第2期239-245,共7页
In this study, a new method for quantitative and efficient measurement for the ground surface movement was developed. The feature of this technique is to identify geomorphic characteristics by image matching analysis,... In this study, a new method for quantitative and efficient measurement for the ground surface movement was developed. The feature of this technique is to identify geomorphic characteristics by image matching analysis, using the intelligent images made from high resolution DEM(Digital Elevation Model). This method is useful to extract the small ground displacement where the surface shape was not intensely deformed. 展开更多
关键词 Ground deformation Ground surface movement Digital Elevation Model(dem Geomorphic image analysis JAPAN
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Spatio-temporal variation of land surface temperature and temperature lapse rate over mountainous Kashmir Himalaya 被引量:6
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作者 Shakil Ahmad ROMSHOO Mohammd RAFIQ Irfan RASHID 《Journal of Mountain Science》 SCIE CSCD 2018年第3期563-576,共14页
In this study, Land Surface Temperature(LST) and its lapse rate over the mountainous Kashmir Himalaya was estimated using MODIS data and correlated with the observed in-situ air temperature(Tair) data. Comparison betw... In this study, Land Surface Temperature(LST) and its lapse rate over the mountainous Kashmir Himalaya was estimated using MODIS data and correlated with the observed in-situ air temperature(Tair) data. Comparison between the MODIS LST and Tair showed a close agreement with the maximum error of the estimate ±1°C and the correlation coefficient >0.90. Analysis of the LST data from 2002-2012 showed an increasing trend at all the selected locations except at a site located in the southeastern part of Kashmir valley. Using the GTOPO30 DEM, MODIS LST data was used to estimate the actual temperature lapse rate(ATLR) along various transects across Kashmir Himalaya, which showed significant variations in space and time ranging from 0.3°C to 1.2°C per 100 m altitude change. This observation is at variance with the standard temperature lapse rate(STLR) of 0.65°C used universally in most of the hydrological and other land surface models. Snowmelt Runoff Model(SRM) was used to determine the efficacy of using the ATLR for simulating the stream flows in one of the glaciated and snow-covered watersheds in Kashmir. The use of ATLR in the SRM model improved the R2 between the observed and predicted streamflows from 0.92 to 0.97.It is hoped that the operational use of satellite-derived LST and ATLR shall improve the understanding and quantification of various processes related to climate, hydrology and ecosystem in the mountainous and data-scarce Himalaya where the use of temperature and ATLR are critical parameters for understanding various land surface and climate processes. 展开更多
关键词 MODIS Land surface Temperature Lapse Rate dem Snowmelt Runoff Model Himalaya
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Methods for the construction of DEMs of artificial slopes considering morphological features and semantic information
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作者 XU Yan ZHAO Ming-wei +4 位作者 LU Jie WANG Chun JIANG Ling YANG Can-can HUANG Xiao-li 《Journal of Mountain Science》 SCIE CSCD 2022年第2期563-577,共15页
As human activities increase,artificially modified terrain is increasingly widely distributed in road,hydrological,and urban construction.Artificially modified terrain plays an important role in protecting from geolog... As human activities increase,artificially modified terrain is increasingly widely distributed in road,hydrological,and urban construction.Artificially modified terrain plays an important role in protecting from geological disasters and in the planning and design of urban landscapes.Compared with natural slopes,artificial slopes have obvious morphological characteristics.Traditional modeling methods are no longer suitable for digital elevation model(DEM)modeling of artificial slopes because they often seriously distort the DEM results.In this paper,from the perspective of morphological characteristics,artificial slopes are divided into two types,namely,regular slopes and irregular slopes,based on whether the top and bottom lines of the artificial slope are parallel.Then,according to the morphological characteristics of the two types of slopes,the following DEM construction methods are designed:the first method(perpendicular+inverse distance weighted)is suitable for regular slopes,and the second method(perpendicular+high-accuracy surface modeling)is suitable for irregular slopes.Finally,a DEM construction test is carried out using the artificial slopes in the study area.The results show that for the regular and irregular slopes in the study area,the construction method proposed in this paper has significant advantages in morphological accuracy over the traditional method(triangulated irregular network),and the elevation accuracy method is also superior to the traditional method(using this method,the mean error and standard deviation error of the regular slope DEM are 0.08 m and 0.13 m,respectively,and those of the irregular slope DEM are 0.08 m and 0.06 m).In addition,the top lines and bottom lines can be included in the DEM construction of the background area after processing the elevation information of the boundary line to realize a smooth transition in the boundary between the artificial slope and the background area. 展开更多
关键词 Artificial slopes dem Morphological characteristics Triangulated irregular network High-accuracy surface modeling
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Integration of Point and Remote Sensing Data for Monitoring Surface Runoff around Madinah City, Saudi Arabia
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作者 ElSayed Ali Hermas Ibrahim Mohammed El-Barodi Khalid Al-Ghamdi 《Advances in Remote Sensing》 2015年第4期287-302,共16页
In response to sporadic rainy storms, the fluvial catchments in the northern, eastern and southern regimes of Medina City produce surface runoff that varies in the frequency and magnitude. The determination of the mos... In response to sporadic rainy storms, the fluvial catchments in the northern, eastern and southern regimes of Medina City produce surface runoff that varies in the frequency and magnitude. The determination of the most frequently flowing catchment(s) through each precipitation event and the spatial characteristics of surface runoff still represent gaps in understanding the hydrological processes associated with flash floods in arid environments. The lack of data in particular precipitation records at reliable temporal and spatial scales is considered one of the essential constraints in understanding these issues. The integration of point precipitation records and the multi-temporal satellite imagery such as LandSat TM and the Tropical Rainfall Monitoring Mission (TRMM) helped retrieve significant surface runoff events through two decades of the last century around Madinah City. The spectral signatures of surface runoff have been clearly identified from the optical remote sensing images acquired after each precipitation event. Investigating the spectral signatures of surface runoff along with its corresponding precipitation records from both Madinah climatic station and the TRMM monthly precipitation indicated that 1) there is no specific threshold of the amount of precipitation required for developing surface runoff;2) while Madinah climatic station provided records of precipitation on the majority of surface runoff, it did not provide records on some monitored surface runoff events;3) the spatial distribution and magnitude of the monthly precipitation of the TRMM images of 1998 have been conformed with all surface runoff events developed in W. Al-Aqeeq;and 4) W. Al-Aqeeq is considered the most frequently flowing valley around Madinah City because it developed surface runoff in response to all the precipitation events. These results emphasize the necessity of establishing a number of climatic and gauge stations in selective locations within the drainage basins around Madinah City. This proposition can facilitate studying the various rainfall and runoff characteristics for designing proper surface water harvesting strategy. 展开更多
关键词 surface RUNofF REMOTE Sensing TRMM Madinach CITY dem
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Creation and Analysis of Earth’s Surface Roughness Maps from Airborne LiDAR Measurements in Downtown Urban Landscape
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作者 Fahmy F. F. Asal 《Journal of Geographic Information System》 2019年第2期212-238,共27页
The Earth’s surface roughness constitutes an important parameter in terrain analysis for studying different environmental and engineering problems. Authors gave different definitions and measures for the earth’s sur... The Earth’s surface roughness constitutes an important parameter in terrain analysis for studying different environmental and engineering problems. Authors gave different definitions and measures for the earth’s surface roughness that usually depend on exploitation of digital elevation data for its reliable determination. This research aimed at exploring the different approaches for defining and extraction of the Earth’s surface roughness from Airborne LiDAR Measurements. It also aimed at evaluating the effects of the window size of the standard deviation filter on the created roughness maps in downtown landscapes using three known approaches namely;standard deviation filtering of the Digital Elevation Model (DEM), standard deviation filtering of the slope gradient model and standard deviation filtering of the profile curvature model. In this context, different roughness maps have been created from Airborne LiDAR measurements of the City of Toronto, Canada using the three filtering approaches with varying window sizes. Visual analysis has shown color tones of small roughness values with smooth textures dominate the roughness maps from small window sizes of the standard deviation filter, however, increasing the window sizes has produced wider variations of the color tones and rougher texture roughness maps. The standard deviations and ranges of the roughness maps from LiDAR DEM have increased due to increasing the filter window size while the skewness and kurtosis have decreased due to increasing the window size, indicating that the roughness maps from larger window sizes are statistically more symmetrical and more consistent. Thus, kurtosis has decreased by 53% and 82% due to increasing the window size to 7 × 7 and 15 × 15 respectively. The standard deviations of the roughness maps from the slope gradient model have increased due to increasing the window size till 15 × 15 while they have decreased with more increases. However, skewness has decreased due to increasing the window size till 15 × 15 and the kurtosis has decreased with higher rate till window size of 11 × 11. In the roughness maps from the profile curvature model, the ranges and skewness have decreased by 93.6% and 82.6% respectively due to increasing the window size to 15 × 15 while, kurtosis has decreased by 58.6%, 76.3% and 93.76% due to increases in the filter window size to 5 × 5, 7 × 7 and 15 × 15 respectively. 展开更多
关键词 surface ROUGHNESS Urban Landscape Airborne LiDAR DSM/dem/DTM SLOPE Gradient Profile CURVATURE Standard Deviation Filtering Spatial ANALYSIS
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Surface Area Estimation, Volume Change Detection in Lime Stone Quarry, Tirunelveli District Using Cartosat-1 Generated Digital Elevation Model (DEM)
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作者 Sudalaimuthu Karuppasamy Sudalayandi Kaliappan +1 位作者 R. Karthiga C. Divya 《Circuits and Systems》 2016年第6期849-858,共10页
The objective of the study was to estimate the change detection in a surface area and volume ana- lysis of the lime stone quarry for the year 2006 and 2014 in Mannur, Tirunelveli district, Tamilnadu. Though the mining... The objective of the study was to estimate the change detection in a surface area and volume ana- lysis of the lime stone quarry for the year 2006 and 2014 in Mannur, Tirunelveli district, Tamilnadu. Though the mining activities are essential for the cement factory, it depletes the ground water table and causes pollution to the Environment. The Integration of Remote Sensing and GIS are effective for analyzing the impact of quarrying on natural resources. In this study, Cartosat-1 satellite data generated Digital Elevation Model (DEM) for measuring surface area and the volume of Lime stone quarry. Temporal volume change study is essential for the government to restrain the misuse of the natural resources by the private sector. In 2006, the surface area and volume of lime stone excavated by 8 mining quarries was 1,991,759.68 m<sup>2</sup> and 112,398,931.9 m<sup>3</sup> respectively. Meanwhile, the surface area utilized and volume of limestone production by the quarry was increased to 2,881,384.64 m<sup>2</sup> and 156,806,929.9 m<sup>3</sup> respectively during the year<sup> </sup>2014. In these 8 years period, quarry surface area utilization increased by 30% and limestone production increased by 28% was observed. This study is useful for the government to monitor the natural resources restrain to over use by the private sector. 展开更多
关键词 Cartosat-1 Lime Stone Quarry surface Area PHOTOGRAMMETRY LPS dem
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Modeled Surface Observations for Spatial Analysis of Landscape Dynamics
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作者 Manoel do Couto Fernandes Tata Lacale Canal dos Santos +2 位作者 Pedro Henrique Ferreira Coura Paulo Marcio Leal de Menezes Alan Jose Salomao Graca 《Journal of Geographic Information System》 2013年第4期409-417,共9页
Landscape dynamics is a geoecological characteristic that defines changes in a landscape spatial structure and function during an established time scale. In this kind of analysis, geoprocessing is an essential tool, b... Landscape dynamics is a geoecological characteristic that defines changes in a landscape spatial structure and function during an established time scale. In this kind of analysis, geoprocessing is an essential tool, because it combines several technologies that help in this work. However, the majority of landscape dynamic investigations do not consider the dimensionality of the data and the information to be used, which is projected not measured from modeled (real) surface observations, and presents underestimated results, mainly in irregular relief landscapes. Considering that, this paper intends to assess the difference between observations on modeled and planimetric surfaces on the interpretation of landscape dynamics. The study was conducted in the massif of Tijuca, Rio de Janeiro (Brazil) using land use and soil cover maps of different times and a digital elevation models (DEM) generated based on a triangular irregular. The results show an increase of dynamic areas values when observations were carried out on modeled surface, as well as the deforestation rate (17.57% or 0.13 km2/year). This survey showed higher values in comparison with observations on planimetric surface, characterizing more realistic interpretations of how the structural elements and analyses made from these are structured in the landscape. 展开更多
关键词 dem Modeled surface Landscape Change
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矿区沉陷DEM多重滤波方法研究
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作者 姚顽强 蒙延斌 +1 位作者 郑俊良 薛志强 《煤矿安全》 CAS 北大核心 2024年第1期167-175,共9页
针对传统地表移动监测方法周期较长、工作量大的问题,通过无人机LiDAR和点云滤波获取地面点云,并构建沉陷DEM,实现地表沉陷监测的方法具有快速、高效的优势;由于现有点云滤波和插值算法构建的沉陷DEM模型仍会包含噪声,限制了该技术在矿... 针对传统地表移动监测方法周期较长、工作量大的问题,通过无人机LiDAR和点云滤波获取地面点云,并构建沉陷DEM,实现地表沉陷监测的方法具有快速、高效的优势;由于现有点云滤波和插值算法构建的沉陷DEM模型仍会包含噪声,限制了该技术在矿区的普及,因此,进一步研究了沉陷DEM噪声的去除方法,对比分析了多重滤波与经典滤波方法。实验分析结果表明:在几种去噪方法中,中值滤波组合维纳滤波的去噪效果最好,保留了下沉盆地的细节特征,能够满足矿区地表形变监测的基本要求。 展开更多
关键词 无人机LiDAR 地表沉陷 点云滤波 沉陷dem 多重滤波
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Re-assessing Vegetation Carbon Storage and Emissions from Land Use Change in China Using Surface Area 被引量:4
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作者 HE Qingsong TAN Shukui +2 位作者 XIE Peng LIU Yaolin LI Jing 《Chinese Geographical Science》 SCIE CSCD 2019年第4期601-613,共13页
Land surface area estimation can provide basic information for accurately estimating vegetation carbon storage under complex terrain. This study selected China, a country dominated by mountains, as an example, and cal... Land surface area estimation can provide basic information for accurately estimating vegetation carbon storage under complex terrain. This study selected China, a country dominated by mountains, as an example, and calculated terrestrial vegetation carbon storage(VCS) for 2000 and 2015 using land surface area and traditional ellipsoid area. The land surface area is estimated by a triangular network on the high precision digital elevation model.The results showed that: 1) The VCS estimated by the surface area measurement in 2000 and 2015 were 0.676 and0.692 Pg C(1 Pg = 1015 g) higher than the VCS calculated using the ellipsoid area, respectively. 2) As the elevation increases, the differences between VCS estimated by surface area measurement and ellipsoid area measurement are expanding. Specially, a clear gap was present starting from an elevation of 500 m, with the relative error exceeds8.99%. 3) The total amount of carbon emitted due to land use change reached 0.114 Pg C. The conversions of forestland and grassland to other land use type are the main reasons of the loss of vegetation carbon storage, resulting in a total amount of biomass carbon storage decreased by 0.942 and 0.111 Pg C, respectively. This study was a preliminary exploration of incorporating land surface area as a factor in resource estimation, which can help more accurately understand the status of resources and the environment in the region. 展开更多
关键词 carbon storage LAND use CHANGE surface area RESOURCE estimation ellipsoidal area China
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