Automatic Landform Recognition from the Perspective of Watershed Spatial Structure Based on Digital Elevation Models

To solve the disadvantages of high difficulty and complexity in studying the spatial topological relation method on different resolution remote sensing images, this paper proposes a spatial topological relationship model based on GeoSOT, which is one of the global subdivision grids. To express spatial objects on different resolution remote sensing images, this paper introduces the spatial objects subdivision location identification. Then, the model calculates spatial topological relation by comparing location identifications in combined table. At last, test shows that it is feasible to analyze the spatial objects topological relations based on GeoSOT and it has high efficiency operation significantly, especially for complicated spatial objects.

Identifying the geographic distribution and erosion risks of various soil erosion regions are critical inputs to the implementation of extensive and effective land protection planning. To obtain more accurate and sufficient erosion information on a large scope, this paper introduced the complex network theory to quantitatively simulate the topographic spatial structure and topological relationship of the erosion area. The watershed was selected as the basic study unit and the directed weighted complex network (DWCN) of each watershed was constructed from DEM data. The directed weighted complex network factor (DWCNF) of each watershed was calculated by the DWCN. After combining DWCNFs with existing SEEF, the soil erosion types and risks of sample areas in the Chinese Loess Plateau were identified by the random forest model. The results show that in both typical and atypical sample areas, the identification performance of soil erosion by combining DWCNFs with existing SEEFs was performed better than that by employing only the DWCNFs or SEEFs dataset. It is suggested that the quantitative description of the spatial structure and topological relationship of the watershed from the perspective of a complex network contributes to obtaining more accurate soil erosion information. The DWCNF of structural entropy, betweenness centrality, and degree centrality were of high importance, which can reliably and effectively identify the types and risks of soil erosion, thus providing a broader factor reference for relevant research. The method proposed in this paper of vectoring terrain into complex network structures is also a novel sight for geological research under complex terrain conditions.

The research of parallel mechanism (PM) configuration involves many problems. From topology to configuration, dimensional constraint, etc., how to establish the relationship between topology and configuration with effective methods is a long-term challenge for the configuration design. In this paper, the chemical molecular spatial structure (CMSS) is linked with the configuration of symmetrical parallel mechanism (SPM). Starting from the methane molecule (CH4), a spatial structural topological relation is obtained. Based on graph theory and the spatial structural topological relation, a new expression method with topological graph and its kinematic pair adjacency matrix for spatial SPM is proposed. Then, the expression and analysis for the characteristics of spatial SPM are obtained. Finally, by taking the 3-RPS PM and the 3-RRC PM as examples, the effectiveness and corresponding consistency of the proposed expression method are successfully verified. The proposed new expression method paves the way for the subsequent digital and automated design and analysis of the SPM configuration.

Digital Elevation Model (DEM) is main input for watershed modelling. Recently, (DEM) is available online for free in different accuracies, and spatial resolutions as a product of several remote sensing satellites. Hence, it is necessary to find out which one is the best for watershed modeling in the study area. In this study, the different accuracies 30m spatial resolution DEMs of (Copernicus, SRTM, and ASTER) can be examined by using Remote sensing (RS) and Geographic Information systems (GIS) techniques to delineate and calculate the topographic characteristics for five different size and topography watersheds (Swaidy, Garlond, Khuwayr Hirah, Naqab, and Kalak) located on both sides of the Mosul reservoir in the northeastern part of Iraq. The analysis results can be led to find that the Copernicus (GLO-30) 30 m resolution DEM is the optimum and most accurate DEM in the selected study area at the vertical accuracy (1.3521 m) and with 95% confidence level is (2.6502 m) represented by the minimum Root Mean Square Error (RMSE) of the elevations differences between check points (MOWR elevations and LIDAR DEM 1 m resolution) and the used DEMs. The watershed delineation and calculated topographic characteristics (watersheds boundary, elevations, area, perimeter and slope areas) are affected by DEM accuracy. Where the considerable accuracy of the differences is with the (Copernicus-SRTM) DEMS at the minimum RMSE of watersheds characteristics.

The spatial characteristics and structure of the exhibition display design are summarized through the analysis of the topological relationship of the exhibition display spatial structure, and the RCTG algorithm in IBM technology is applied to extract the above-described exhibition spatial topological relationship. Based on the actual situation of the exhibition design, the structural space constraint relationship is determined, and at the same time, the model API provided by the BIM platform is called to construct the component model based on the topological constraint relationship. Aiming at the problems of large differences in lighting distribution and large differences in color in the process of exhibition display design, we optimize such problems through visual element processing operations and realize visual element configuration from three aspects: color, picture, and white space. A case study of the exhibition designed in this paper is conducted by setting the model parameters. The results present that in the simulation analysis of scene combination optimization when, the entry rate grows to 18vis./min, at this time, the user’s overall exhibition viewing satisfaction reaches the peak, and the optimal limit number of people is 46. In addition, in the lighting analysis of the side interface + top interface of the exhibition, 30% high side windows + 25% decentralized strip skylights (B1+F1) have the highest values of each lighting, the proportion of area with a lighting coefficient of >2% (99.497%), the proportion of area with an illuminance of 400lux (91.571), the average lighting coefficient (7.046), and the uniformity of lighting (0.192). This study verifies the practical feasibility of research on exhibition display design based on topology optimization through experimental analysis.

The resolution of digital elevation model (DEM) used for watershed delineation and data extracted from the delineated watershed relevant to hydrography plays an important role in the calibration of hydrological models. The effect of DEM resolution on the drainage length, watershed area and average slope are studied in many earlier works. DEM resolution can have impact on hydrologic modeling parameters, water quality simulation results. The impacts of DEM resolution on results of the watershed response and water quality modeling are studied using HSPF (Hydrologic Simulation Program Fortran) model applied to a watershed in Kentucky in this study. Three major streams in this watershed are impaired due to pathogen pollution according to the current state of Kentucky water quality standard set for recreation. The effects of DEM resolution on water quality modeling and calibration for fecal coliform bacteria are studied using a HSPF model. Results from this study indicate that the DEM resolution affects hydrography parameters of the delineated watershed, influence the calibration process, and the non-point and point source loadings to the streams in the watershed.

Representing topological information for the Semantic Web often involves qualitative defined natural language terms such as “In”. This can be the case when exact coordinates of spatial regions are not available or they are unreliable. Topological spatial relations are the most important aspect of spatial representation and reasoning. In addition to topology, often the exact size of regions is not known as well, but the relations between sizes (e.g., larger, equal) are known. In this work we propose and evaluate an integrated representation of topological relations (RCC-5 and RCC-8) and qualitative size relations using OWL object properties and axioms, combined with reasoning rules expressed using SWRL, embedded into the ontology. Different representations are implemented and evaluated.KeywordsSpatial Representation and ReasoningSemantic WebRules

Cloud computing technology is changing the mode of the spatial information industry which is applied and provides new ideas for it. Since Hadoop platform provides easy expansion, high performance, high fault tolerance and other advantages, we propose a novel vector spatial data storage schema based on it to solve the problems on how to use cloud computing technology to directly manage spatial data and present data topological relations. Firstly, vector spatial data storage schema is designed based on column-oriented storage structures and key/value mapping to express spatial topological relations. Secondly, we design middleware and merge with vector spatial data storage schema in order to directly store spatial data and present geospatial data access refinement schemes based on GeoTools toolkit. Thirdly, we verify the middleware and the data storage schema through Hadoop cluster experiments. Comprehensive experiments demonstrate that our proposal is efficient and applicable to directly storing large-scale vector spatial data and timely express spatial topological relations.

For remote sensing imagery, spatial relationships are extracted by segmentation and classification. Unlike traditional vector relationships, spatial relationship reasoning is equivalent to constraint satisfaction problems in the image process. Based on 9-intersect model, the paper discuss spatial topological relationship between image objects to provide a theoretical and technical support for low levels of image segmentation, high-level analysis.

Models for data representation and presentation in WebGIS systems are based on concepts of borderlines, nets, territory, space and place, and the representation of abstract concepts are transmitted through graphic form, by means of images, photographs or cartographic representations of regions. The topological, projective, and Euclidean spatial relations connected with the process of world construction and conception promote experiences lived in space and that involve sensations, perception, and conception, which together with human emotional and rational characteristics, allow the elaboration of mental models. This paper presents a model and its prototype for interpretation, representation and presentation of geographical information based on sounds so as to allow information interpretation and analysis in WebGIS systems. In order to check the efficiency and effectiveness of the proposed methodology, a computer prototype applied to Google Maps was developed, in which the proposed method was applied and tested with a group of blind people.

Role and member selection in team formation using resource estimation for large-scale multi-agent systems

In this paper, we extend our previous work on deformable image registration to inhomogenous tissues. Inhomogenous tissues include the tissues with embedded tumors, which is common in clinical applications. It is a very challenging task since the registration method that works for homogenous tissues may not work well with inhomogenous tissues. The maximum error normally occurs in the regions with tumors and often exceeds the acceptable error threshold. In this paper, we propose a new error correction method with adaptive weighting to reduce the maximum registration error. Our previous fast deformable registration method is used in the inner loop. We have also proposed a new evaluation metric average error of deformation field (AEDF) to evaluate the registration accuracy in regions between vessels and bifurcation points. We have validated the proposed method using liver MR images from human subjects. AEDF results show that the proposed method can greatly reduce the maximum registration errors when compared with the previous method with no adaptive weighting. The proposed method has the potential to be used in clinical applications to reduce registration errors in regions with tumors.

The development of formal models of spatial relations is a topic of great importance in spatial reasoning, geographic information systems (GIS) and computer vision, and has gained much attention from researchers across these research areas during the past two decades. In recent years significant achievements have been made on the development of models of spatial relations between spatial objects with precisely defined boundaries. However, these models cannot be directly applied to spatial objects with indeterminate boundaries which are found in many applications in geographic analysis and image understanding. This article develops a method for approximately analyzing binary topological relations between geographic regions with indeterminate boundaries based upon previous work on topological spatial relations and fuzzy sets. In addition, examples are given to demonstrate the method and related concepts. It is shown that the eight binary topological relations between regions in a two-dimensional space can be easily determined by the method.

In this paper, we present an approach to comparing control flow graphs of binary programs by matching their basic blocks. We first set up an initial match and propagate it to reach a stable state. We consider the matched pairs to identify overall similarities. To evaluate the proposed method, we perform experiments on real-world Java applications, and compare their performance with previous structural matching method. In the experimental results, the proposed method shows more reliable results than previous method at distinguishing similar control flow graphs.

This letter proposes a more advanced joint maximum a posteriori (MAP) adaptation using a prior model based on a probabilistic scheme utilizing the bilinear transformation (BIT) concept. The proposed method not only has scalable parameters but is also based on a single prior distribution without the heuristic parameters of the previous joint BIT-MAP method. Experiment results, irrespective of the amount of adaptation data, show that the proposed method leads to a consistent improvement over the previous method.