In this paper we evaluate the feasibility of seamless and efficient integration of terrestrial communication systems with satellite networks. This aspect is considered by standardisation bodies such as ETSI [1], 5 G-P...In this paper we evaluate the feasibility of seamless and efficient integration of terrestrial communication systems with satellite networks. This aspect is considered by standardisation bodies such as ETSI [1], 5 G-PPP [2] and 3 GPP [3]. A comprehensive system is designed and implemented in an emulation prototype, including standard 3 GPP LTE core network functionality [4] with its different layers: networking, data forwarding, control, management and monitoring and is validated through performance measurements. This work is a technical feasibility study of extending terrestrial communication systems with satellite networks as backhaul, increasing the energy efficiency, network robustness during natural disasters as well as being an alternative for peak-time data forwarding of the terrestrial communication services. Due to its global coverage property, terrestrial-satellite integration provides an obvious extension of communication services towards isolated and remote areas and an alternative for rural or highly distributed/highly mobile enterprise networks.展开更多
The monitoring of highwall slopes at open-pit mines is an important task to ensure safe mining. For this reason, several techniques such as total station, radar, terrestrial Light Detection and Ranging (LIDAR) can b...The monitoring of highwall slopes at open-pit mines is an important task to ensure safe mining. For this reason, several techniques such as total station, radar, terrestrial Light Detection and Ranging (LIDAR) can be employed for surface measurement. The objective of this study is to investigate mesh algorithms, which can be used to interpolate 3D models of pit walls. Experiments were carried out at Coc Sau open-pit mine at Quang Ninh province of Vietnam, and at experimental mine of Akademia Gtrniczo-Hutnicza University of Science and Technology in Cracow, Poland. First, 3D point cloud data for the study area was acquired by using terrestrial LIDAR, then was used to generate mesh surfaces using three algorithms--Delaunay 2.5D XY Plane, Delaunay 2.5D Best Fitting Plane, and Mesh from Points. After that, the results were rectified and optimized. Subsequently, the optimized meshes were used for generation of non-uniform rational basis spline (NURBS) surfaces. Then, the NURBS surface accuracy was assessed. The results showed that the average distance between surface and point cloud was within range of 5.6-5.8 mm with deviation of 6.2-6.8 mm, depending on the used mesh. Additionally, the quality of surfaces depends on the quality of input data set and the algorithm used to generate mesh network, and the accuracy of computed NURBS surfaces fitting into pointset was 4-5 times lower than that of optimized mesh fitting. However, the accuracy of the final product allows determining displacements on the level of centimeters.展开更多
Land subsidence phenomena caused by the overexploitation of the aquifers require the holistic knowledge of the geological, tectonic, hydrogeological and especially the geotechnical conditions of the affected sites in ...Land subsidence phenomena caused by the overexploitation of the aquifers require the holistic knowledge of the geological, tectonic, hydrogeological and especially the geotechnical conditions of the affected sites in order to be mitigated. The current paper focuses on the study of the phenomena taking place at the Amyntaio sub-basin, northern Greece, hosting the homonymous open pit coal mine,operating there the last two decades. The mining as well as the rising agriculture activities have led to a significant drawdown of the ground water level triggering extensive ground subsidence phenomena,causing damages at the nearby villages, infrastructure and farmlands. The production and evaluation of engineering geological–geotechnical maps as well as of thematic tectonic and hydrogeological maps proved that the knowledge of this data is crucial for the interpretation of the land subsidence mechanism and the spatial distribution of its effects.展开更多
Strategic environmental assessment (SEA) is the process to evaluate, in a systematic way, the possible environmental impacts caused by decision making such as policy, plan, and program. It is of highly significance ...Strategic environmental assessment (SEA) is the process to evaluate, in a systematic way, the possible environmental impacts caused by decision making such as policy, plan, and program. It is of highly significance to improve decision-making. This article reviewed the researches on SEA as well as its practices in Taiwan, Hong Kong and the mainland of China. The regulations, methodologies, and effect of practices were compared. The regulations on SEA had been enacted at three places respectively. With the largest spatial area and rapid economic development pace, the mainland has carded out more SEA practices recently than the other two places, but their final effect still need to be confirmed. It was said that Hong Kong had acquired considerable experiences on SEA, while practice of SEA at Taiwan lagged behind.展开更多
Sixty springs of the Cuneo Province inland plains were sampled and analyzed for several chemical variables. Multi-variate analysis (PCA) of all the data was undertaken. The first principal component was positively c...Sixty springs of the Cuneo Province inland plains were sampled and analyzed for several chemical variables. Multi-variate analysis (PCA) of all the data was undertaken. The first principal component was positively correlated with chlorides, sulphites, hardness, and negatively correlated with altitude. The second principal component was positively correlated with DO and pH. Results showed that 4 groups of springs could be distinguished on the basis of environmental variables. A small number of springs did not group with the geographically more proximal springs but with another group due to a greater degree of affinity on the basis of the hydrochemical variables.展开更多
The research performance of top universities in China is revealed in this study and analyzed using the essential science indicators(ESI) database.Different types of bibliometric indicators are applied in this study,in...The research performance of top universities in China is revealed in this study and analyzed using the essential science indicators(ESI) database.Different types of bibliometric indicators are applied in this study,including publication output and impact indicators.This study finds that the academic performance of universities in China is advancing rapidly,with many universities coming out near the top of the rankings,especially in terms of quantity of papers.The quantitative performance of universities in China is remarkable.The research results show that there is a considerable gap between quality and quantity of research output at the top universities of China,with research influence concentrated on some specific fields for selected universities.Engineering,Chemistry and Material Science are the fields with relatively outstanding performance in the top universities.展开更多
In this research,the Factor Analysis model of measuring provincial low carbon development in China has been constructed.Based on data from 30 provinces,an empirical study was developed to measure comprehensive low car...In this research,the Factor Analysis model of measuring provincial low carbon development in China has been constructed.Based on data from 30 provinces,an empirical study was developed to measure comprehensive low carbon development using the Factor Analysis model(Principal Components method and Normalized Varimax Rotation).The results reveal that the provincial marks of low carbon development are generally low and only nine provinces have high marks(more than 0.80).The results also show significant regional disparity.The provincial marks of the eastern region are higher than both the middle and western provinces of China's Mainland.All of the provinces with high marks(more than 0.90) are located in the eastern region,and those with the lowest marks(0.60) are located in the middle region.Furthermore,regional disparity in low carbon development follows the same pattern as economic development in China.Finally,some suggestions for decision-makers are presented.展开更多
Digital elevation model (DEM) is the most popular product for three-dimensional (3D) digital representation of bare Earth surface and can be produced by many techniques with different characteristics and ground sa...Digital elevation model (DEM) is the most popular product for three-dimensional (3D) digital representation of bare Earth surface and can be produced by many techniques with different characteristics and ground sampling distances (GSD). Space-borne opti- cal and synthetic aperture radar (SAR) imaging are two of the most preferred and modern techniques for DEM generation. Using them, global DEMs that cover almost entire Earth are produced with low cost and time saving processing. In this study, we aimed to assess the Satellite pour robservation de la Terre-5 (SPOT-5), High Resolution Stereoscopic (HRS), the Advanced Space-borne Thermal Emission and Reflection Radiometer (ASTER), and the Shuttle Radar Topography Mission (SRTM) C-band global DEMs, produced with space-borne optical and SAR imaging. For the assessment, a reference DEM derived from 1 : 1000 scaled digital photogrammetric maps was used. The study is performed in 100 km2 study area in Istanbul including various land classes such as open land, forest, built-up land, scrub and rough terrain obtained from Landsat data. The analyses were realized considering three vertical accuracy types as fundamental, supplemental, and consolidated, defined by national digital elevation program (NDEP) of USA. The results showed that, vertical accuracy of SRTM C-band DEM is better than optical models in all three accuracy types despite having the largest grid spacing. The result of SPOT-5 HRS DEM is very close by SRTM and superior in comparison with ASTER models.展开更多
Global historical land use datasets are widely used in global environmental change studies; however, uncertainties in the included pasture data have not been evaluated. In this study, using trend, relative difference ...Global historical land use datasets are widely used in global environmental change studies; however, uncertainties in the included pasture data have not been evaluated. In this study, using trend, relative difference ratio(RDR), and spatial comparisons, we evaluated the accuracy of China pasture data in the HYDE(versions 3.1 and 3.2), SAGE, and PJ datasets using historical document-based reconstructions, including the land use datasets for China covering 1935–1997(hereafter Ge-dataset)and Northeast China covering the 1700 s–2000(hereafter Ye-dataset), and the satellite-based China's Land-Use/cover Datasets(CLUDs) for 1980–2015. Four important results were obtained.(1) China pasture area in the HYDE, SAGE, and PJ datasets and grassland area in the Ge-dataset, Ye-dataset, and CLUDs show both disparate trends and large differences in absolute values.(2)Spatially, 50.9%, 52.8%, and 63.0% pasture/grassland grids in 2000 had RDRs greater than 60% between HYDE3.1, HYDE3.2,and SAGE datasets, and CLUDs, respectively. The percentage of grids with RDRs less than 20% were 24.9%, 26.7%, and 16.0%,respectively.(3) Based on HYDE3.2, the spatial distribution of pasture in Northeast China over the last 300 year has expanded,which is in contrast to the results from the Ye-dataset, which shows the spatial distribution of grassland shrinking because of human reclamation activities.(4) The large contrasts between the global datasets and Chinese native datasets are due to differences in pasture/grassland definitions, land use practices, and spatial reconstruction methods.展开更多
基金part of the ESA ARTES 1 study"SatCom integration with LTE-based core network emulator"contract no.ESA 4000111941/15/NL/EM.
文摘In this paper we evaluate the feasibility of seamless and efficient integration of terrestrial communication systems with satellite networks. This aspect is considered by standardisation bodies such as ETSI [1], 5 G-PPP [2] and 3 GPP [3]. A comprehensive system is designed and implemented in an emulation prototype, including standard 3 GPP LTE core network functionality [4] with its different layers: networking, data forwarding, control, management and monitoring and is validated through performance measurements. This work is a technical feasibility study of extending terrestrial communication systems with satellite networks as backhaul, increasing the energy efficiency, network robustness during natural disasters as well as being an alternative for peak-time data forwarding of the terrestrial communication services. Due to its global coverage property, terrestrial-satellite integration provides an obvious extension of communication services towards isolated and remote areas and an alternative for rural or highly distributed/highly mobile enterprise networks.
文摘The monitoring of highwall slopes at open-pit mines is an important task to ensure safe mining. For this reason, several techniques such as total station, radar, terrestrial Light Detection and Ranging (LIDAR) can be employed for surface measurement. The objective of this study is to investigate mesh algorithms, which can be used to interpolate 3D models of pit walls. Experiments were carried out at Coc Sau open-pit mine at Quang Ninh province of Vietnam, and at experimental mine of Akademia Gtrniczo-Hutnicza University of Science and Technology in Cracow, Poland. First, 3D point cloud data for the study area was acquired by using terrestrial LIDAR, then was used to generate mesh surfaces using three algorithms--Delaunay 2.5D XY Plane, Delaunay 2.5D Best Fitting Plane, and Mesh from Points. After that, the results were rectified and optimized. Subsequently, the optimized meshes were used for generation of non-uniform rational basis spline (NURBS) surfaces. Then, the NURBS surface accuracy was assessed. The results showed that the average distance between surface and point cloud was within range of 5.6-5.8 mm with deviation of 6.2-6.8 mm, depending on the used mesh. Additionally, the quality of surfaces depends on the quality of input data set and the algorithm used to generate mesh network, and the accuracy of computed NURBS surfaces fitting into pointset was 4-5 times lower than that of optimized mesh fitting. However, the accuracy of the final product allows determining displacements on the level of centimeters.
文摘Land subsidence phenomena caused by the overexploitation of the aquifers require the holistic knowledge of the geological, tectonic, hydrogeological and especially the geotechnical conditions of the affected sites in order to be mitigated. The current paper focuses on the study of the phenomena taking place at the Amyntaio sub-basin, northern Greece, hosting the homonymous open pit coal mine,operating there the last two decades. The mining as well as the rising agriculture activities have led to a significant drawdown of the ground water level triggering extensive ground subsidence phenomena,causing damages at the nearby villages, infrastructure and farmlands. The production and evaluation of engineering geological–geotechnical maps as well as of thematic tectonic and hydrogeological maps proved that the knowledge of this data is crucial for the interpretation of the land subsidence mechanism and the spatial distribution of its effects.
文摘Strategic environmental assessment (SEA) is the process to evaluate, in a systematic way, the possible environmental impacts caused by decision making such as policy, plan, and program. It is of highly significance to improve decision-making. This article reviewed the researches on SEA as well as its practices in Taiwan, Hong Kong and the mainland of China. The regulations, methodologies, and effect of practices were compared. The regulations on SEA had been enacted at three places respectively. With the largest spatial area and rapid economic development pace, the mainland has carded out more SEA practices recently than the other two places, but their final effect still need to be confirmed. It was said that Hong Kong had acquired considerable experiences on SEA, while practice of SEA at Taiwan lagged behind.
文摘Sixty springs of the Cuneo Province inland plains were sampled and analyzed for several chemical variables. Multi-variate analysis (PCA) of all the data was undertaken. The first principal component was positively correlated with chlorides, sulphites, hardness, and negatively correlated with altitude. The second principal component was positively correlated with DO and pH. Results showed that 4 groups of springs could be distinguished on the basis of environmental variables. A small number of springs did not group with the geographically more proximal springs but with another group due to a greater degree of affinity on the basis of the hydrochemical variables.
基金Supported by the National Natural Science Fund Program(No.71073153)
文摘The research performance of top universities in China is revealed in this study and analyzed using the essential science indicators(ESI) database.Different types of bibliometric indicators are applied in this study,including publication output and impact indicators.This study finds that the academic performance of universities in China is advancing rapidly,with many universities coming out near the top of the rankings,especially in terms of quantity of papers.The quantitative performance of universities in China is remarkable.The research results show that there is a considerable gap between quality and quantity of research output at the top universities of China,with research influence concentrated on some specific fields for selected universities.Engineering,Chemistry and Material Science are the fields with relatively outstanding performance in the top universities.
基金supported by Chinese National Science & Technology Board (Grant No. 2009DFB90120)
文摘In this research,the Factor Analysis model of measuring provincial low carbon development in China has been constructed.Based on data from 30 provinces,an empirical study was developed to measure comprehensive low carbon development using the Factor Analysis model(Principal Components method and Normalized Varimax Rotation).The results reveal that the provincial marks of low carbon development are generally low and only nine provinces have high marks(more than 0.80).The results also show significant regional disparity.The provincial marks of the eastern region are higher than both the middle and western provinces of China's Mainland.All of the provinces with high marks(more than 0.90) are located in the eastern region,and those with the lowest marks(0.60) are located in the middle region.Furthermore,regional disparity in low carbon development follows the same pattern as economic development in China.Finally,some suggestions for decision-makers are presented.
基金Under the auspices of Scientific Research Project Coordinatorship of Yildiz Technical University,Turkey(No.20100503KAP01)
文摘Digital elevation model (DEM) is the most popular product for three-dimensional (3D) digital representation of bare Earth surface and can be produced by many techniques with different characteristics and ground sampling distances (GSD). Space-borne opti- cal and synthetic aperture radar (SAR) imaging are two of the most preferred and modern techniques for DEM generation. Using them, global DEMs that cover almost entire Earth are produced with low cost and time saving processing. In this study, we aimed to assess the Satellite pour robservation de la Terre-5 (SPOT-5), High Resolution Stereoscopic (HRS), the Advanced Space-borne Thermal Emission and Reflection Radiometer (ASTER), and the Shuttle Radar Topography Mission (SRTM) C-band global DEMs, produced with space-borne optical and SAR imaging. For the assessment, a reference DEM derived from 1 : 1000 scaled digital photogrammetric maps was used. The study is performed in 100 km2 study area in Istanbul including various land classes such as open land, forest, built-up land, scrub and rough terrain obtained from Landsat data. The analyses were realized considering three vertical accuracy types as fundamental, supplemental, and consolidated, defined by national digital elevation program (NDEP) of USA. The results showed that, vertical accuracy of SRTM C-band DEM is better than optical models in all three accuracy types despite having the largest grid spacing. The result of SPOT-5 HRS DEM is very close by SRTM and superior in comparison with ASTER models.
基金supported by the National Key Research and Development Program of China on Global Change (Grant No. 2017YFA0603304)the National Natural Science Foundation of China (Grant Nos. 41671149, 41701228)
文摘Global historical land use datasets are widely used in global environmental change studies; however, uncertainties in the included pasture data have not been evaluated. In this study, using trend, relative difference ratio(RDR), and spatial comparisons, we evaluated the accuracy of China pasture data in the HYDE(versions 3.1 and 3.2), SAGE, and PJ datasets using historical document-based reconstructions, including the land use datasets for China covering 1935–1997(hereafter Ge-dataset)and Northeast China covering the 1700 s–2000(hereafter Ye-dataset), and the satellite-based China's Land-Use/cover Datasets(CLUDs) for 1980–2015. Four important results were obtained.(1) China pasture area in the HYDE, SAGE, and PJ datasets and grassland area in the Ge-dataset, Ye-dataset, and CLUDs show both disparate trends and large differences in absolute values.(2)Spatially, 50.9%, 52.8%, and 63.0% pasture/grassland grids in 2000 had RDRs greater than 60% between HYDE3.1, HYDE3.2,and SAGE datasets, and CLUDs, respectively. The percentage of grids with RDRs less than 20% were 24.9%, 26.7%, and 16.0%,respectively.(3) Based on HYDE3.2, the spatial distribution of pasture in Northeast China over the last 300 year has expanded,which is in contrast to the results from the Ye-dataset, which shows the spatial distribution of grassland shrinking because of human reclamation activities.(4) The large contrasts between the global datasets and Chinese native datasets are due to differences in pasture/grassland definitions, land use practices, and spatial reconstruction methods.