Mangroves are woody plant communities that appear in tropical and subtropical regions,mainly in intertidal zones along the coastlines.Despite their considerable benefits to humans and the surrounding environment,their...Mangroves are woody plant communities that appear in tropical and subtropical regions,mainly in intertidal zones along the coastlines.Despite their considerable benefits to humans and the surrounding environment,their existence is threatened by anthropogenic activities and natural drivers.Accordingly,it is vital to conduct efficient efforts to increase mangrove plantations by identifying suitable locations.These efforts are required to support conservation and plantation practices and lower the mortality rate of seedlings.Therefore,identifying ecologically potential areas for plantation practices is mandatory to ensure a higher success rate.This study aimed to identify suitable locations for mangrove plantations along the southern coastal frontiers of Hormozgan,Iran.To this end,we applied a hybrid Fuzzy-DEMATEL-ANP(FDANP)model as a Multi-Criteria Decision Making(MCDM)approach to determine the relative importance of different criteria,combined with geospatial and remote sensing data.In this regard,ten relevant sources of environmental criteria,including meteorological,topographical,and geomorphological,were used in the modeling.The statistical evaluation demonstrated the high potential of the developed approach for suitable location identification.Based on the final results,6.10%and 20.80%of the study area were classified as very-high suitable and very-low suitable areas.The obtained values can elucidate the path for decision-makers and managers for better conservation and plantation planning.Moreover,the utility of charge-free remote sensing data allows cost-effective implementation of such an approach for other regions by interested researchers and governing organizations.展开更多
A new ocean wave and sea surface current monitoring system with horizontally-(HH) and vertically-(VV) polarized X-band radar was developed.Two experiments into the use of the radar system were carried out at two sites...A new ocean wave and sea surface current monitoring system with horizontally-(HH) and vertically-(VV) polarized X-band radar was developed.Two experiments into the use of the radar system were carried out at two sites,respectively,for calibration process in Zhangzi Island of the Yellow Sea,and for validation in the Yellow Sea and South China Sea.Ocean wave parameters and sea surface current velocities were retrieved from the dual polarized radar image sequences based on an inverse method.The results obtained from dual-polarized radar data sets acquired in Zhangzi Island are compared with those from an ocean directional buoy.The results show that ocean wave parameters and sea surface current velocities retrieved from radar image sets are in a good agreement with those observed by the buoy.In particular,it has been found that the vertically-polarized radar is better than the horizontally-polarized radar in retrieving ocean wave parameters,especially in detecting the significant wave height below 1.0 m.展开更多
Building detection in very high resolution (VHR) images is crucial for mapping and analysing urban environments. Since buildings are elevated objects, elevation data need to be integrated with images for reliable dete...Building detection in very high resolution (VHR) images is crucial for mapping and analysing urban environments. Since buildings are elevated objects, elevation data need to be integrated with images for reliable detection. This process requires two critical steps: optical-elevation data co-registration and aboveground elevation calculation. These two steps are still challenging to some extent. Therefore, this paper introduces optical-elevation data co-registration and normalization techniques for generating a dataset that facilitates elevation-based building detection. For achieving accurate co-registration, a dense set of stereo-based elevations is generated and co-registered to their relevant image based on their corresponding image locations. To normalize these co-registered elevations, the bare-earth elevations are detected based on classification information of some terrain-level features after achieving the image co-registration. The developed method was executed and validated. After implementation, 80% overall-quality of detection result was achieved with 94% correct detection. Together, the developed techniques successfully facilitate the incorporation of stereo-based elevations for detecting buildings in VHR remote sensing images.展开更多
This paper introduces some of the image processing techniques developed in the Canada Research Chair in Advanced Geomatics Image Processing Laboratory (CRC-AGIP Lab) and in the Department of Geodesy and Geomatics Engi...This paper introduces some of the image processing techniques developed in the Canada Research Chair in Advanced Geomatics Image Processing Laboratory (CRC-AGIP Lab) and in the Department of Geodesy and Geomatics Engineering (GGE) at the University of New Brunswick (UNB), Canada. The techniques were developed by innovatively/“smartly” utilizing the characteristics of the available very high resolution optical remote sensing images to solve important problems or create new applications in photogrammetry and remote sensing. The techniques to be introduced are: automated image fusion (UNB-PanSharp), satellite image online mapping, street view technology, moving vehicle detection using single set satellite imagery, supervised image segmentation, image matching in smooth areas, and change detection using images from different viewing angles. Because of their broad application potential, some of the techniques have made a global impact, and some have demonstrated the potential for a global impact.展开更多
This article presents the modal frequency recordings of a rigid bridge, monitored by the GPS receivers (Global Positioning System) with a data recording rate of 100 Hz and accelerometers. The GPS data processing was p...This article presents the modal frequency recordings of a rigid bridge, monitored by the GPS receivers (Global Positioning System) with a data recording rate of 100 Hz and accelerometers. The GPS data processing was performed through the double-difference phase, using the adjusted interferometry technique (i.e. phase residue method—PRM®). In the method, the double-difference phase of the carrier L1 is realized by using two satellites only, one was positioned at the zenith of the structure and the other satellite was positioned near the horizon. The results of the parametric adjustment of the PRM observations were finalized through software Interferometry, mathematical algorithm were applied and compared with the accelerometer. The comparison served to validate the use of GPS as a fast and reliable instrument for the preliminary monitoring of the dynamic behavior of the bridge, road artworks which are common in several countries, especially in the Brazilian road network. The data time series from the GPS and accelerometers were processed using the Wavelet. The detection of frequencies means that the combination of 100 Hz GPS receivers and the PRM allows detecting vibrations up to 5 mm. It presented significant results which were never obtained by the Fourier Transform.展开更多
Ecotourism is a sustainable, green and smokeless industry of the society by providing alternative source to the livelihood and local community, in order to re-naturalize the environment to bring the man closer to the ...Ecotourism is a sustainable, green and smokeless industry of the society by providing alternative source to the livelihood and local community, in order to re-naturalize the environment to bring the man closer to the natural environment. The use of web application has changed the way tourists gather information about tourist attraction spots of the research area. The aim of the study is to assess and identify ecotourism attraction sites of Chokie Mountain watersheds for touristic activities to develop a web-based GIS mapping portal for the improvement of nature-based ecotourism activities. The web-based GIS portal for Web Mapping Application is available for the user with the skills necessary to create standard web mapping services. We have implemented web mapping services based on formal cartographic visualization rules in the open source QGIS software and threejs JavaScript plugin. Threejs plugin is used for 3D visualization, interaction and export terrain data, map canvas image and vector data to HTML page and JS. The result of web-based GIS portal supports spatial and non-spatial database of tourist attraction and tourist service data with attractive user interface.展开更多
One of the most powerful functions of Geographic Information System for Transportation (GIS-T) is Dynamic Segmentation (DS), which is used to increase the efficiency and precision of road management by generating segm...One of the most powerful functions of Geographic Information System for Transportation (GIS-T) is Dynamic Segmentation (DS), which is used to increase the efficiency and precision of road management by generating segments based on attributes. The road segments describing transportation data are both spatially and temporally referenced. For a variety of transportation applications, historical road segments must be preserved. This study presents an appropriate approach to preserve and retrieve the historical road segments efficiently. In the proposed method, only the portions of segments of a time stamp that have been changed into new segments rather than storing the entire segments for every old time stamp are recorded .The storage of these portions is based on the type of changes. A recursive algorithm is developed to retrieve all segments for every old time stamp. Experimental results using real data of Tehran City, Iran justify the strength of the proposed approach in many aspects. An important achievement of the results is that database volume for 2006, 2007 and 2008 within the Historical Line Event Table (HLET) is reduced by 70%, 80% and 78%, respectively. The proposed method has the potential to prevent from vast data redundancy and the unnecessary storage of entire segments for each time stamp. Since the present technique is performed on ordinary plain tables that are readable by all GIS software, special software platforms to manage the storage and retrieval of historical segments are not needed. In addition, this method simplifies spatio-temporal queries.展开更多
Objective:To determine the suitable ecological habitats of Aedes(Ae.)aegypti and Ae.albopictus in Iran due to climate change by the 2070s.Methods:All data relating to the spatial distribution of Ae.aegypti and Ae.albo...Objective:To determine the suitable ecological habitats of Aedes(Ae.)aegypti and Ae.albopictus in Iran due to climate change by the 2070s.Methods:All data relating to the spatial distribution of Ae.aegypti and Ae.albopictus worldwide,which indicated the geographical coordinates of the collection sites of these mosquitoes,were extracted from online scientific websites and entered into an Excel file.The effect of climatic and environmental variables on these mosquitoes was evaluated using the MaxEnt model in the current and future climatic conditions in the 2030s,2050s,and 2070s.Results:The most suitable areas for the establishment of Ae.aegypti are located in the southern and northern coastal areas of Iran,based on the model outputs.The modelling result for suitable ecological niches of Ae.albopictus shows that in the current climatic conditions,the southern half of Iran from east to west,and parts of the northern coasts are prone to the presence of this species.In the future,some regions,such as Gilan and Golestan provinces,will have more potential to exist/establish Ae.albopictus.Also,according to the different climate change scenarios,suitable habitats for this species will gradually change to the northwest and west of the country.The temperature of the wettest season of the year(Bio8)and average annual temperature(Bio1)were the most effective factors in predicting the model for Ae.aegypti and Ae.albopictus,respectively.Conclusions:It is required to focus on entomological studies using different collection methods in the vulnerable areas of Iran.The future modelling results can also be used for long-term planning to prevent the entry and establishment of these invasive Aedes vectors in the country.展开更多
Continuous global positioning system （GPS） in northern Sumatra detected signal of the ongoing physical process of postseismic deformation after the M9.2 2004 Sumatra-Andaman earthquake. We analyze the character- ist...Continuous global positioning system （GPS） in northern Sumatra detected signal of the ongoing physical process of postseismic deformation after the M9.2 2004 Sumatra-Andaman earthquake. We analyze the character- istics of postseismic deformation of the 2004 earthquake based on GPS networks operated by BIG, and the others named AGNeSS, and SuGAr networks located in northern Sumatra. We use a simple analytical logarithmic and exponential function to evaluate the postseismic deforma- tion parameters of the 2004 earthquake. We find that GPS data in northern Sumatra during time periods of 2005-2012 are fit better using the logarithmic function with dog of 104.2 ± 0.1 than using the exponential function. Our result clearly indicates that other physical mechanisms of post- seismic deformation should be taken into account rather than a single physical mechanism of afterslip only.展开更多
The Global Navigation Satellite System (GNSS) is widely utilized for accurate positioning.One commonly applied method to obtain precise coordinate estimates is by implementing the relative positioning in network mode....The Global Navigation Satellite System (GNSS) is widely utilized for accurate positioning.One commonly applied method to obtain precise coordinate estimates is by implementing the relative positioning in network mode.However,this approach can be complex and challenging.Fortunately,The Japan Aerospace Exploration Agency (JAXA) offers freely available satellite orbit and clock correction products called Multi-GNSS Advanced Demonstration Tool for Orbit and Clock Analysis (MADOCA),which can enhance positioning accuracy through the precise point positioning (PPP) method.This study focuses on evaluating PPP static mode positioning using MADOCA products and comparing the results with the highly precise relative positioning method.By analyzing a network of 20 GNSS stations in Indonesia,we found that the PPP method using MADOCA products provided favorable positioning estimates.The median discrepancies and the corresponding median absolute deviation (MAD) for easting,northing,and up components were estimated as 9±18 mm,10±9 mm,and 3±40 mm,respectively.These results indicate that PPP with MADOCA products can be a reliable alternative for establishing Indonesia's horizontal control networks,particularly for orders 0,1,2,and 3,and for a broad spectrum of geoscience monitoring activities.However,considerations such as epoch transformations and seismic activities should be taken into account for accurate positioning applications that comply with the definition of the national reference framework.展开更多
Earthquakes pose a significant threat to urban environments,highlighting the need for enhanced seismic resilience.To improve understanding of earthquake dynamics and the interplay of seismic activity across space,this...Earthquakes pose a significant threat to urban environments,highlighting the need for enhanced seismic resilience.To improve understanding of earthquake dynamics and the interplay of seismic activity across space,this study introduces a novel approach for identifying associated regions that exhibit interdependence seismic behavior,revealing a network structure of earthquake interplays.This model was applied to earthquakes exceeding 3.0 Mw in Iran(1976–2023),using a 1°×1°grid.Monthly and seasonal timespans were evaluated to capture potential short-term and long-term interactions.The model revealed a network of interdependent seismic regions in southern and southwestern Iran,predominantly located within the Zagros belt.Notably,the strongest associations were observed between spatial units 45 and 36,located approximately 6°apart in southern Iran.These units exhibited significant association in both monthly and seasonal scenarios,with support values of 0.28 and 0.65,and average confidence values of 0.58 and 0.84,respectively.The second significant bilateral relation was detected between neighboring spatial units 22 and 36,with support values of 0.26 and 0.59,and average confidence values of 0.57 and 0.80,respectively.The recognized structure was compared to the established seismotectonic zoning.This network aligns with established seismotectonic provinces,particularly in the seasonal scenario.The model also identified potential interactions between distinct zones in the monthly scenario,highlighting areas where urban development strategies might need reevaluation.Additionally,the analysis revealed implicit causal relationships between spatial units,pinpointing areas susceptible to or influencing seismic activities elsewhere.These results contribute to a deeper understanding of crustal structure,earthquake propagation,and the potential for seismic activity to trigger earthquakes in nearby or distant areas.This knowledge is crucial for developing effective strategies to build earthquake-resilient cities.展开更多
This study examined wetland trends in the St.Lawrence Seaway(~500,000 km^(2))in Canada over the past four decades.To this end,historical Landsat data within the Google Earth Engine(GEE)big geo data platform were proce...This study examined wetland trends in the St.Lawrence Seaway(~500,000 km^(2))in Canada over the past four decades.To this end,historical Landsat data within the Google Earth Engine(GEE)big geo data platform were processed.Reference samples were scrutinized using the Continuous Change Detection and Classification(CCDC)algorithm to identify spectrally unchanged samples.These spectrally unchanged samples were subsequently employed as training data within an object-based Random Forest(RF)model to generate wetland maps from 1984 to 2021.Subsequently,a change analysis was conducted to calculate the loss and gain of different wetland types.Overall,it was observed that approximately 45%(184,434 km^(2))and 55%(220,778 km^(2))of the entire study area are covered by wetland and non-wetland categories,respectively.It was also observed that 2.46%(12,495 km^(2))of the study area was changed during 40 years.Overall,there was a decline in the Bog and Fen classes,while the Marsh,Swamp,Forest,Grassland/Shrubland,Cropland,and Barren classes had an increase.Finally,the wetland gain and loss were 6,793 km^(2)and 5,701 km^(2),respectively.This study demonstrated that the use of Landsat data,along with advanced machine learning and GEE,could provide valuable assistance for wetland classification and change studies.展开更多
The sedimentation of metals can preserve the historical record of contaminant input from local and regional sources and provide information on the historical changes in regionalwater and sediment quality. We report th...The sedimentation of metals can preserve the historical record of contaminant input from local and regional sources and provide information on the historical changes in regionalwater and sediment quality. We report the 210Pb activities and the heavy metal （Cd, Cr, Cu, Mn, Pb and Zn）depth profiles from sediment cores retrieved in 2010. The mean sedimentation rates of 0.85-1.5 cm/yr aredetermined by 210 Pbdating. The sediments in the tidal flat have recorded heavy metaldeposition and thus allow the establishment of a connection between the temporal evolution of the heavy metal pollution and the historical changes in the economicdevelopment of Lianyungang. The enrichment factors （EF） are calculated to estimate the level of contamination stored in these sediments. The results show that in the studied sites, Cr and Cudisplay low EF values and are mainly from lithogenic origin. For the other studied trace metals, a great variability in the sedimentary record is observed. Significant anthropogenic enrichment over the last 50 years is revealed at the tidal flat that receives fluvial inputs. Zinc is the elementwith the highest EF values, followed by the order of Pb 〉 Cd 〉 Mn 〉 Cu and Cr. The temporal variations of the heavy metals peakduring the late 1980s to the early2000s and show adecreasing trend afterward. The pollution intensity of the tidal flat isdetermined by using EF and thegeo-accumulation index （Igeo ）,which show that, based on the Igeo scale, the tidal flat of Haizhou Bay is unpolluted to moderately polluted.展开更多
Owing to lack of observational data and accurate definition,it is difficult to distinguish the Kuroshio intrusion water from the Pacific Ocean into the South China Sea（SCS）.By using a passive tracer to identify the ...Owing to lack of observational data and accurate definition,it is difficult to distinguish the Kuroshio intrusion water from the Pacific Ocean into the South China Sea（SCS）.By using a passive tracer to identify the Kuroshio water based on an observation-validated three-dimensional numerical model MITgcm,the spatio-temporal variation of the Kuroshio intrusion water into the SCS has been investigated.Our result shows the Kuroshio intrusion is of distinct seasonal variation in both horizontal and vertical directions.In winter,the intruding Kuroshio water reaches the farthest,almost occupying the area from 18°N to 23°N and 114°E to 121°E,with a small branch flowing towards the Taiwan Strait.The intrusion region of the Kuroshio water decreases with depth gradually.However,in summer,the Kuroshio water is confined to the east of 118°E without any branch reaching the Taiwan Strait; meanwhile the intrusion region of the Kuroshio water increases from the surface to the depth about 205 m,then it decreases with depth.The estimated annual mean of Kuroshio Intrusion Transport（KIT） via the Luzon Strait is westward to the SCS in an amount of –3.86×106 m3/s,which is larger than the annual mean of Luzon Strait Transport（LST） of –3.15×106 m3/s.The KIT above 250 m accounts for 60%–80% of the LST throughout the entire water column.By analyzing interannual variation of the Kuroshio intrusion from the year 2003 to 2012,we find that the Kuroshio branch flowing into the Taiwan Strait is the weaker in winter of La Ni？a years than those in El Ni？o and normal years,which may be attributed to the wind stress curl off the southeast China then.Furthermore,the KIT correlates the Ni？o 3.4 index from 2003 to 2012 with a correlation coefficient of 0.41,which is lower than that of the LST with the Ni？o 3.4 index,i.e.,0.78.展开更多
Increasing population in urban areas and limitations of suitable lands for developing houses and urban infrastructure have led to the vertical development in cities.However,these developments are managed by a cadastra...Increasing population in urban areas and limitations of suitable lands for developing houses and urban infrastructure have led to the vertical development in cities.However,these developments are managed by a cadastral system which is mainly two-dimensional and cannot efficiently represent Rights,Restrictions,and Responsibilities(RRRs)in complex scenarios.In fact,a three-dimensional cadastre is required for efficiently registering and representing RRRs.In this paper,a 3D proximity analysis was proposed and implemented to determine RRRs and associated easement rights in non-topology-based data structures.This method can be used to investigate the surrounding spaces of a subject apartment unit or storage in a high-rise.The performance of the developed method was evaluated in a large complex high-rise in Tehran,Iran.The results confirmed that the proposed method can correctly identify the neighbor spaces in complex scenarios.展开更多
ANNs （Artificial neural networks） are used extensively in remote sensing image processing. It has been proven that BPNNs （back-propagation neural networks） have high attainable classification accuracy. However, th...ANNs （Artificial neural networks） are used extensively in remote sensing image processing. It has been proven that BPNNs （back-propagation neural networks） have high attainable classification accuracy. However, there is a noticeable variation in the achieved accuracies due to different network designs and implementations. Hence, researchers usually need to conduct several experimental trials before they can finalize the network design. This is a time consuming process which significantly reduces the effectiveness of using BPNNs and the final design may still not be optimal. Therefore, there is a need to see whether there are some common guidelines for effective design and implementation of BPNNs. With this aim in mind, this paper attempts to find and summarize the common guidelines suggested by different authors through literature review and discussion of the findings. To provide readers with background and contextual information, some ANN fundamentals are also introduced.展开更多
The integration of optical images and elevation data is of great importance for 3D-assisted mapping applications. Very high resolution (VHR) satellite images provide ideal geo-data for mapping building information. Si...The integration of optical images and elevation data is of great importance for 3D-assisted mapping applications. Very high resolution (VHR) satellite images provide ideal geo-data for mapping building information. Since buildings are inherently elevated objects, these images need to be co-registered with their elevation data for reliable building detection results. However, accurate co-registration is extremely difficult for off-nadir VHR images acquired over dense urban areas. Therefore, this research proposes a Disparity-Based Elevation Co-Registration (DECR) method for generating a Line-of-Sight Digital Surface Model (LoS-DSM) to efficiently achieve image-elevation data co-registration with pixel-level accuracy. Relative to the traditional photogrammetric approach, the RMSE value of the derived elevations is found to be less than 2 pixels. The applicability of the DECR method is demonstrated through elevation-based building detection (EBD) in a challenging dense urban area. The quality of the detection result is found to be more than 90%. Additionally, the detected objects were geo-referenced successfully to their correct ground locations to allow direct integration with other maps. In comparison to the original LoS-DSM development algorithm, the DECR algorithm is more efficient by reducing the calculation steps, preserving the co-registration accuracy, and minimizing the need for elevation normalization in dense urban areas.展开更多
In the change detection application of remote sensing, commonly the variation in the brightness values of the pixels/objects in bi-temporal image is used as an indicator for detecting changes. However, there exist eff...In the change detection application of remote sensing, commonly the variation in the brightness values of the pixels/objects in bi-temporal image is used as an indicator for detecting changes. However, there exist effects, other than a change in the objects that can cause variations in the brightness values. One of the effects is the illumination difference on steep surfaces mainly steeproofs of houses in very high resolution images, specifically in off-nadir images. This can introduce the problem of false change detection results. This problem becomes more serious in images with different view-angles. In this study, we propose a methodology to improve the building change detection accuracy using imagery taken under different illumination conditions and different view-angles. This is done by using the Patch-Wise Co-Registration (PWCR) method to overcome the misregistration problem caused by view-angle difference and applying Topographic Correction (TC) methods on pixel intensities to attenuate the effect of illumination angle variation on the building roofs. To select a proper TC method, four of the most widely used correction methods, namely C-correction, Minnaert, Enhanced Minnaert (for slope), and Cosine Correction are evaluated in this study. The results proved that the proposed methodology is capable to improve the change detection accuracy. Specifically, the correction using the C-correction and Enhanced Minnaert improved the change detection accuracy by around 35% in an area with a large number of steep-roof houses imaged under various solar angles.展开更多
Structured study of spatial objects and their relationships leads to a better cognition of the geospatial information and creates the concept of context at a higher level of abstraction.This study is aimed at providin...Structured study of spatial objects and their relationships leads to a better cognition of the geospatial information and creates the concept of context at a higher level of abstraction.This study is aimed at providing a comprehensive definition of the context for geospatial objects.A combination of binary qualitative spatial relationships(i.e.direction,distance,and topological relations)among the members of a set of spatial objects will be used accordingly.In addition,by incorporating the general concept of context,obtained from either static data(attributes in a database)or dynamic data(sensors),the compact context of spatial objects will be introduced.Our framework for presentation of the involved knowledge and conception about the objects in context is also explored using ontology and description logic because of powerful conceptualization of relationships,either spatial or non-spatial,integrally.For this purpose,the hierarchies of main structure and object properties are formed at first.The constraint and characteristics of classes,such as subclasses,equivalent classes,cardinality etc.,and object properties,such as being functional,transitive,symmetric,asymmetric,inverse functional,disjoint etc.,are discovered and presented in more detail using web ontology language in description logic mode.The implementation is then performed in the framework of semantic web and extensible markup language syntaxes.The method ultimately facilitates,spatial reasoning by effective querying in a semantic framework taking pellet reasoner and SPARQL(a recursive acronym for SPARQL Protocol and RDF Query Language).展开更多
In many deformation analyses,the partial derivatives at the interpolated scattered data points are required.In this paper,the Gaussian Radial Basis Functions(GRBF)is proposed for the interpolation and differentiation ...In many deformation analyses,the partial derivatives at the interpolated scattered data points are required.In this paper,the Gaussian Radial Basis Functions(GRBF)is proposed for the interpolation and differentiation of the scattered data in the vertical deformation analysis.For the optimal selection of the shape parameter,which is crucial in the GRBF interpolation,two methods are used:the Power Gaussian Radial Basis Functions(PGRBF)and Leave One Out Cross Validation(LOOCV)(LGRBF).We compared the PGRBF and LGRBF to the traditional interpolation methods such as the Finite Element Method(FEM),polynomials,Moving Least Squares(MLS),and the usual GRBF in both the simulated and actual Interferometric Synthetic Aperture Radar(InSAR)data.The estimated results showed that the surface interpolation accuracy was greatly improved by LGRBF and PGRBF methods in comparison withFEM,polynomial,and MLS methods.Finally,LGRBF and PGRBF interpolation methods are used to compute invariant vertical deformation parameters,i.e.,changes in Gaussian and mean Curvatures in the Groningen area in the North of Netherlands.展开更多
基金funded by Erasmus+ICM programme for a 3-month and 5-month stay at Lund University,Lund,Sweden,and thank the European Union.
文摘Mangroves are woody plant communities that appear in tropical and subtropical regions,mainly in intertidal zones along the coastlines.Despite their considerable benefits to humans and the surrounding environment,their existence is threatened by anthropogenic activities and natural drivers.Accordingly,it is vital to conduct efficient efforts to increase mangrove plantations by identifying suitable locations.These efforts are required to support conservation and plantation practices and lower the mortality rate of seedlings.Therefore,identifying ecologically potential areas for plantation practices is mandatory to ensure a higher success rate.This study aimed to identify suitable locations for mangrove plantations along the southern coastal frontiers of Hormozgan,Iran.To this end,we applied a hybrid Fuzzy-DEMATEL-ANP(FDANP)model as a Multi-Criteria Decision Making(MCDM)approach to determine the relative importance of different criteria,combined with geospatial and remote sensing data.In this regard,ten relevant sources of environmental criteria,including meteorological,topographical,and geomorphological,were used in the modeling.The statistical evaluation demonstrated the high potential of the developed approach for suitable location identification.Based on the final results,6.10%and 20.80%of the study area were classified as very-high suitable and very-low suitable areas.The obtained values can elucidate the path for decision-makers and managers for better conservation and plantation planning.Moreover,the utility of charge-free remote sensing data allows cost-effective implementation of such an approach for other regions by interested researchers and governing organizations.
基金Supported by the Knowledge Innovation Program of the Chinese Academy of Sciences (Nos.KZCX1-YW-12-04,KZCX2-YW-201)the Instrument Developing Project of the Chinese Academy of Sciences (No.YZ200724)
文摘A new ocean wave and sea surface current monitoring system with horizontally-(HH) and vertically-(VV) polarized X-band radar was developed.Two experiments into the use of the radar system were carried out at two sites,respectively,for calibration process in Zhangzi Island of the Yellow Sea,and for validation in the Yellow Sea and South China Sea.Ocean wave parameters and sea surface current velocities were retrieved from the dual polarized radar image sequences based on an inverse method.The results obtained from dual-polarized radar data sets acquired in Zhangzi Island are compared with those from an ocean directional buoy.The results show that ocean wave parameters and sea surface current velocities retrieved from radar image sets are in a good agreement with those observed by the buoy.In particular,it has been found that the vertically-polarized radar is better than the horizontally-polarized radar in retrieving ocean wave parameters,especially in detecting the significant wave height below 1.0 m.
文摘Building detection in very high resolution (VHR) images is crucial for mapping and analysing urban environments. Since buildings are elevated objects, elevation data need to be integrated with images for reliable detection. This process requires two critical steps: optical-elevation data co-registration and aboveground elevation calculation. These two steps are still challenging to some extent. Therefore, this paper introduces optical-elevation data co-registration and normalization techniques for generating a dataset that facilitates elevation-based building detection. For achieving accurate co-registration, a dense set of stereo-based elevations is generated and co-registered to their relevant image based on their corresponding image locations. To normalize these co-registered elevations, the bare-earth elevations are detected based on classification information of some terrain-level features after achieving the image co-registration. The developed method was executed and validated. After implementation, 80% overall-quality of detection result was achieved with 94% correct detection. Together, the developed techniques successfully facilitate the incorporation of stereo-based elevations for detecting buildings in VHR remote sensing images.
文摘This paper introduces some of the image processing techniques developed in the Canada Research Chair in Advanced Geomatics Image Processing Laboratory (CRC-AGIP Lab) and in the Department of Geodesy and Geomatics Engineering (GGE) at the University of New Brunswick (UNB), Canada. The techniques were developed by innovatively/“smartly” utilizing the characteristics of the available very high resolution optical remote sensing images to solve important problems or create new applications in photogrammetry and remote sensing. The techniques to be introduced are: automated image fusion (UNB-PanSharp), satellite image online mapping, street view technology, moving vehicle detection using single set satellite imagery, supervised image segmentation, image matching in smooth areas, and change detection using images from different viewing angles. Because of their broad application potential, some of the techniques have made a global impact, and some have demonstrated the potential for a global impact.
文摘This article presents the modal frequency recordings of a rigid bridge, monitored by the GPS receivers (Global Positioning System) with a data recording rate of 100 Hz and accelerometers. The GPS data processing was performed through the double-difference phase, using the adjusted interferometry technique (i.e. phase residue method—PRM®). In the method, the double-difference phase of the carrier L1 is realized by using two satellites only, one was positioned at the zenith of the structure and the other satellite was positioned near the horizon. The results of the parametric adjustment of the PRM observations were finalized through software Interferometry, mathematical algorithm were applied and compared with the accelerometer. The comparison served to validate the use of GPS as a fast and reliable instrument for the preliminary monitoring of the dynamic behavior of the bridge, road artworks which are common in several countries, especially in the Brazilian road network. The data time series from the GPS and accelerometers were processed using the Wavelet. The detection of frequencies means that the combination of 100 Hz GPS receivers and the PRM allows detecting vibrations up to 5 mm. It presented significant results which were never obtained by the Fourier Transform.
文摘Ecotourism is a sustainable, green and smokeless industry of the society by providing alternative source to the livelihood and local community, in order to re-naturalize the environment to bring the man closer to the natural environment. The use of web application has changed the way tourists gather information about tourist attraction spots of the research area. The aim of the study is to assess and identify ecotourism attraction sites of Chokie Mountain watersheds for touristic activities to develop a web-based GIS mapping portal for the improvement of nature-based ecotourism activities. The web-based GIS portal for Web Mapping Application is available for the user with the skills necessary to create standard web mapping services. We have implemented web mapping services based on formal cartographic visualization rules in the open source QGIS software and threejs JavaScript plugin. Threejs plugin is used for 3D visualization, interaction and export terrain data, map canvas image and vector data to HTML page and JS. The result of web-based GIS portal supports spatial and non-spatial database of tourist attraction and tourist service data with attractive user interface.
文摘One of the most powerful functions of Geographic Information System for Transportation (GIS-T) is Dynamic Segmentation (DS), which is used to increase the efficiency and precision of road management by generating segments based on attributes. The road segments describing transportation data are both spatially and temporally referenced. For a variety of transportation applications, historical road segments must be preserved. This study presents an appropriate approach to preserve and retrieve the historical road segments efficiently. In the proposed method, only the portions of segments of a time stamp that have been changed into new segments rather than storing the entire segments for every old time stamp are recorded .The storage of these portions is based on the type of changes. A recursive algorithm is developed to retrieve all segments for every old time stamp. Experimental results using real data of Tehran City, Iran justify the strength of the proposed approach in many aspects. An important achievement of the results is that database volume for 2006, 2007 and 2008 within the Historical Line Event Table (HLET) is reduced by 70%, 80% and 78%, respectively. The proposed method has the potential to prevent from vast data redundancy and the unnecessary storage of entire segments for each time stamp. Since the present technique is performed on ordinary plain tables that are readable by all GIS software, special software platforms to manage the storage and retrieval of historical segments are not needed. In addition, this method simplifies spatio-temporal queries.
基金Research Deputy,Tehran University of Medical Sciences,grant No.46857。
文摘Objective:To determine the suitable ecological habitats of Aedes(Ae.)aegypti and Ae.albopictus in Iran due to climate change by the 2070s.Methods:All data relating to the spatial distribution of Ae.aegypti and Ae.albopictus worldwide,which indicated the geographical coordinates of the collection sites of these mosquitoes,were extracted from online scientific websites and entered into an Excel file.The effect of climatic and environmental variables on these mosquitoes was evaluated using the MaxEnt model in the current and future climatic conditions in the 2030s,2050s,and 2070s.Results:The most suitable areas for the establishment of Ae.aegypti are located in the southern and northern coastal areas of Iran,based on the model outputs.The modelling result for suitable ecological niches of Ae.albopictus shows that in the current climatic conditions,the southern half of Iran from east to west,and parts of the northern coasts are prone to the presence of this species.In the future,some regions,such as Gilan and Golestan provinces,will have more potential to exist/establish Ae.albopictus.Also,according to the different climate change scenarios,suitable habitats for this species will gradually change to the northwest and west of the country.The temperature of the wettest season of the year(Bio8)and average annual temperature(Bio1)were the most effective factors in predicting the model for Ae.aegypti and Ae.albopictus,respectively.Conclusions:It is required to focus on entomological studies using different collection methods in the vulnerable areas of Iran.The future modelling results can also be used for long-term planning to prevent the entry and establishment of these invasive Aedes vectors in the country.
基金funded by the PLN APJ of Sukabumi No.203/060/APJ-SKI/2010Indonesia Endowment Fund for Education(LPDP) No.PRJ1048/LPDP/2015the Australian Department of Foreign Affairs and Trade(DFAT) for Graduate Research on Earthquake and Active Tectonics at the Bandung Institute of Technology
文摘Continuous global positioning system （GPS） in northern Sumatra detected signal of the ongoing physical process of postseismic deformation after the M9.2 2004 Sumatra-Andaman earthquake. We analyze the character- istics of postseismic deformation of the 2004 earthquake based on GPS networks operated by BIG, and the others named AGNeSS, and SuGAr networks located in northern Sumatra. We use a simple analytical logarithmic and exponential function to evaluate the postseismic deforma- tion parameters of the 2004 earthquake. We find that GPS data in northern Sumatra during time periods of 2005-2012 are fit better using the logarithmic function with dog of 104.2 ± 0.1 than using the exponential function. Our result clearly indicates that other physical mechanisms of post- seismic deformation should be taken into account rather than a single physical mechanism of afterslip only.
文摘The Global Navigation Satellite System (GNSS) is widely utilized for accurate positioning.One commonly applied method to obtain precise coordinate estimates is by implementing the relative positioning in network mode.However,this approach can be complex and challenging.Fortunately,The Japan Aerospace Exploration Agency (JAXA) offers freely available satellite orbit and clock correction products called Multi-GNSS Advanced Demonstration Tool for Orbit and Clock Analysis (MADOCA),which can enhance positioning accuracy through the precise point positioning (PPP) method.This study focuses on evaluating PPP static mode positioning using MADOCA products and comparing the results with the highly precise relative positioning method.By analyzing a network of 20 GNSS stations in Indonesia,we found that the PPP method using MADOCA products provided favorable positioning estimates.The median discrepancies and the corresponding median absolute deviation (MAD) for easting,northing,and up components were estimated as 9±18 mm,10±9 mm,and 3±40 mm,respectively.These results indicate that PPP with MADOCA products can be a reliable alternative for establishing Indonesia's horizontal control networks,particularly for orders 0,1,2,and 3,and for a broad spectrum of geoscience monitoring activities.However,considerations such as epoch transformations and seismic activities should be taken into account for accurate positioning applications that comply with the definition of the national reference framework.
文摘Earthquakes pose a significant threat to urban environments,highlighting the need for enhanced seismic resilience.To improve understanding of earthquake dynamics and the interplay of seismic activity across space,this study introduces a novel approach for identifying associated regions that exhibit interdependence seismic behavior,revealing a network structure of earthquake interplays.This model was applied to earthquakes exceeding 3.0 Mw in Iran(1976–2023),using a 1°×1°grid.Monthly and seasonal timespans were evaluated to capture potential short-term and long-term interactions.The model revealed a network of interdependent seismic regions in southern and southwestern Iran,predominantly located within the Zagros belt.Notably,the strongest associations were observed between spatial units 45 and 36,located approximately 6°apart in southern Iran.These units exhibited significant association in both monthly and seasonal scenarios,with support values of 0.28 and 0.65,and average confidence values of 0.58 and 0.84,respectively.The second significant bilateral relation was detected between neighboring spatial units 22 and 36,with support values of 0.26 and 0.59,and average confidence values of 0.57 and 0.80,respectively.The recognized structure was compared to the established seismotectonic zoning.This network aligns with established seismotectonic provinces,particularly in the seasonal scenario.The model also identified potential interactions between distinct zones in the monthly scenario,highlighting areas where urban development strategies might need reevaluation.Additionally,the analysis revealed implicit causal relationships between spatial units,pinpointing areas susceptible to or influencing seismic activities elsewhere.These results contribute to a deeper understanding of crustal structure,earthquake propagation,and the potential for seismic activity to trigger earthquakes in nearby or distant areas.This knowledge is crucial for developing effective strategies to build earthquake-resilient cities.
文摘This study examined wetland trends in the St.Lawrence Seaway(~500,000 km^(2))in Canada over the past four decades.To this end,historical Landsat data within the Google Earth Engine(GEE)big geo data platform were processed.Reference samples were scrutinized using the Continuous Change Detection and Classification(CCDC)algorithm to identify spectrally unchanged samples.These spectrally unchanged samples were subsequently employed as training data within an object-based Random Forest(RF)model to generate wetland maps from 1984 to 2021.Subsequently,a change analysis was conducted to calculate the loss and gain of different wetland types.Overall,it was observed that approximately 45%(184,434 km^(2))and 55%(220,778 km^(2))of the entire study area are covered by wetland and non-wetland categories,respectively.It was also observed that 2.46%(12,495 km^(2))of the study area was changed during 40 years.Overall,there was a decline in the Bog and Fen classes,while the Marsh,Swamp,Forest,Grassland/Shrubland,Cropland,and Barren classes had an increase.Finally,the wetland gain and loss were 6,793 km^(2)and 5,701 km^(2),respectively.This study demonstrated that the use of Landsat data,along with advanced machine learning and GEE,could provide valuable assistance for wetland classification and change studies.
基金supported by the Open Fund of State Key Laboratory of Pollution Control and Resources Reuse(No.PCRRF11024)the Fostering Project of Major Research Plan of National Natural Sciences Foundation of China(No.91025022)+3 种基金the Natural Science Foundation of Huaihai Institute of Technology(No.Z2011001)the Priming Scientific Research Foundation for the Junior Teachersin Huaihai Institute of Technology(No.KQ09041)the Project of Innovation from Undergraduate in Jiangsu Province(No.SY201311641107001) the project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘The sedimentation of metals can preserve the historical record of contaminant input from local and regional sources and provide information on the historical changes in regionalwater and sediment quality. We report the 210Pb activities and the heavy metal （Cd, Cr, Cu, Mn, Pb and Zn）depth profiles from sediment cores retrieved in 2010. The mean sedimentation rates of 0.85-1.5 cm/yr aredetermined by 210 Pbdating. The sediments in the tidal flat have recorded heavy metaldeposition and thus allow the establishment of a connection between the temporal evolution of the heavy metal pollution and the historical changes in the economicdevelopment of Lianyungang. The enrichment factors （EF） are calculated to estimate the level of contamination stored in these sediments. The results show that in the studied sites, Cr and Cudisplay low EF values and are mainly from lithogenic origin. For the other studied trace metals, a great variability in the sedimentary record is observed. Significant anthropogenic enrichment over the last 50 years is revealed at the tidal flat that receives fluvial inputs. Zinc is the elementwith the highest EF values, followed by the order of Pb 〉 Cd 〉 Mn 〉 Cu and Cr. The temporal variations of the heavy metals peakduring the late 1980s to the early2000s and show adecreasing trend afterward. The pollution intensity of the tidal flat isdetermined by using EF and thegeo-accumulation index （Igeo ）,which show that, based on the Igeo scale, the tidal flat of Haizhou Bay is unpolluted to moderately polluted.
基金The Special Fund of Strategic Leading Science and Technology from Chinese Academy of Sciences under contract Nos XDA11020305 and XDA13030103the National Basic Research Program of China under contract No.2013CB956101+1 种基金the National Science Foundation Council Grant of China under contract Nos 41206009,41430964 and 41521005the Chinese Academy of Sciences/State Administration of Foreign Experts Affairs International Partnership Program for Creative Research Teams under contract No.20140491532
文摘Owing to lack of observational data and accurate definition,it is difficult to distinguish the Kuroshio intrusion water from the Pacific Ocean into the South China Sea（SCS）.By using a passive tracer to identify the Kuroshio water based on an observation-validated three-dimensional numerical model MITgcm,the spatio-temporal variation of the Kuroshio intrusion water into the SCS has been investigated.Our result shows the Kuroshio intrusion is of distinct seasonal variation in both horizontal and vertical directions.In winter,the intruding Kuroshio water reaches the farthest,almost occupying the area from 18°N to 23°N and 114°E to 121°E,with a small branch flowing towards the Taiwan Strait.The intrusion region of the Kuroshio water decreases with depth gradually.However,in summer,the Kuroshio water is confined to the east of 118°E without any branch reaching the Taiwan Strait; meanwhile the intrusion region of the Kuroshio water increases from the surface to the depth about 205 m,then it decreases with depth.The estimated annual mean of Kuroshio Intrusion Transport（KIT） via the Luzon Strait is westward to the SCS in an amount of –3.86×106 m3/s,which is larger than the annual mean of Luzon Strait Transport（LST） of –3.15×106 m3/s.The KIT above 250 m accounts for 60%–80% of the LST throughout the entire water column.By analyzing interannual variation of the Kuroshio intrusion from the year 2003 to 2012,we find that the Kuroshio branch flowing into the Taiwan Strait is the weaker in winter of La Ni？a years than those in El Ni？o and normal years,which may be attributed to the wind stress curl off the southeast China then.Furthermore,the KIT correlates the Ni？o 3.4 index from 2003 to 2012 with a correlation coefficient of 0.41,which is lower than that of the LST with the Ni？o 3.4 index,i.e.,0.78.
文摘Increasing population in urban areas and limitations of suitable lands for developing houses and urban infrastructure have led to the vertical development in cities.However,these developments are managed by a cadastral system which is mainly two-dimensional and cannot efficiently represent Rights,Restrictions,and Responsibilities(RRRs)in complex scenarios.In fact,a three-dimensional cadastre is required for efficiently registering and representing RRRs.In this paper,a 3D proximity analysis was proposed and implemented to determine RRRs and associated easement rights in non-topology-based data structures.This method can be used to investigate the surrounding spaces of a subject apartment unit or storage in a high-rise.The performance of the developed method was evaluated in a large complex high-rise in Tehran,Iran.The results confirmed that the proposed method can correctly identify the neighbor spaces in complex scenarios.
文摘ANNs （Artificial neural networks） are used extensively in remote sensing image processing. It has been proven that BPNNs （back-propagation neural networks） have high attainable classification accuracy. However, there is a noticeable variation in the achieved accuracies due to different network designs and implementations. Hence, researchers usually need to conduct several experimental trials before they can finalize the network design. This is a time consuming process which significantly reduces the effectiveness of using BPNNs and the final design may still not be optimal. Therefore, there is a need to see whether there are some common guidelines for effective design and implementation of BPNNs. With this aim in mind, this paper attempts to find and summarize the common guidelines suggested by different authors through literature review and discussion of the findings. To provide readers with background and contextual information, some ANN fundamentals are also introduced.
文摘The integration of optical images and elevation data is of great importance for 3D-assisted mapping applications. Very high resolution (VHR) satellite images provide ideal geo-data for mapping building information. Since buildings are inherently elevated objects, these images need to be co-registered with their elevation data for reliable building detection results. However, accurate co-registration is extremely difficult for off-nadir VHR images acquired over dense urban areas. Therefore, this research proposes a Disparity-Based Elevation Co-Registration (DECR) method for generating a Line-of-Sight Digital Surface Model (LoS-DSM) to efficiently achieve image-elevation data co-registration with pixel-level accuracy. Relative to the traditional photogrammetric approach, the RMSE value of the derived elevations is found to be less than 2 pixels. The applicability of the DECR method is demonstrated through elevation-based building detection (EBD) in a challenging dense urban area. The quality of the detection result is found to be more than 90%. Additionally, the detected objects were geo-referenced successfully to their correct ground locations to allow direct integration with other maps. In comparison to the original LoS-DSM development algorithm, the DECR algorithm is more efficient by reducing the calculation steps, preserving the co-registration accuracy, and minimizing the need for elevation normalization in dense urban areas.
文摘In the change detection application of remote sensing, commonly the variation in the brightness values of the pixels/objects in bi-temporal image is used as an indicator for detecting changes. However, there exist effects, other than a change in the objects that can cause variations in the brightness values. One of the effects is the illumination difference on steep surfaces mainly steeproofs of houses in very high resolution images, specifically in off-nadir images. This can introduce the problem of false change detection results. This problem becomes more serious in images with different view-angles. In this study, we propose a methodology to improve the building change detection accuracy using imagery taken under different illumination conditions and different view-angles. This is done by using the Patch-Wise Co-Registration (PWCR) method to overcome the misregistration problem caused by view-angle difference and applying Topographic Correction (TC) methods on pixel intensities to attenuate the effect of illumination angle variation on the building roofs. To select a proper TC method, four of the most widely used correction methods, namely C-correction, Minnaert, Enhanced Minnaert (for slope), and Cosine Correction are evaluated in this study. The results proved that the proposed methodology is capable to improve the change detection accuracy. Specifically, the correction using the C-correction and Enhanced Minnaert improved the change detection accuracy by around 35% in an area with a large number of steep-roof houses imaged under various solar angles.
文摘Structured study of spatial objects and their relationships leads to a better cognition of the geospatial information and creates the concept of context at a higher level of abstraction.This study is aimed at providing a comprehensive definition of the context for geospatial objects.A combination of binary qualitative spatial relationships(i.e.direction,distance,and topological relations)among the members of a set of spatial objects will be used accordingly.In addition,by incorporating the general concept of context,obtained from either static data(attributes in a database)or dynamic data(sensors),the compact context of spatial objects will be introduced.Our framework for presentation of the involved knowledge and conception about the objects in context is also explored using ontology and description logic because of powerful conceptualization of relationships,either spatial or non-spatial,integrally.For this purpose,the hierarchies of main structure and object properties are formed at first.The constraint and characteristics of classes,such as subclasses,equivalent classes,cardinality etc.,and object properties,such as being functional,transitive,symmetric,asymmetric,inverse functional,disjoint etc.,are discovered and presented in more detail using web ontology language in description logic mode.The implementation is then performed in the framework of semantic web and extensible markup language syntaxes.The method ultimately facilitates,spatial reasoning by effective querying in a semantic framework taking pellet reasoner and SPARQL(a recursive acronym for SPARQL Protocol and RDF Query Language).
文摘In many deformation analyses,the partial derivatives at the interpolated scattered data points are required.In this paper,the Gaussian Radial Basis Functions(GRBF)is proposed for the interpolation and differentiation of the scattered data in the vertical deformation analysis.For the optimal selection of the shape parameter,which is crucial in the GRBF interpolation,two methods are used:the Power Gaussian Radial Basis Functions(PGRBF)and Leave One Out Cross Validation(LOOCV)(LGRBF).We compared the PGRBF and LGRBF to the traditional interpolation methods such as the Finite Element Method(FEM),polynomials,Moving Least Squares(MLS),and the usual GRBF in both the simulated and actual Interferometric Synthetic Aperture Radar(InSAR)data.The estimated results showed that the surface interpolation accuracy was greatly improved by LGRBF and PGRBF methods in comparison withFEM,polynomial,and MLS methods.Finally,LGRBF and PGRBF interpolation methods are used to compute invariant vertical deformation parameters,i.e.,changes in Gaussian and mean Curvatures in the Groningen area in the North of Netherlands.
