Geographic Information System Component Research Articles

A Novel Query Method for Spatial Database Based on Improved K-Nearest Neighbor Algorithm

Spatial database is a spatial information database and is the core component of geographic information systems (GIS). Aiming at the problem that time complexity of k-nearest neighbor (kNN) querying algorithms are proportionate to scale of training samples, an efficient query method for spatial database based on the Spark framework and the reversed k-nearest neighbor (RkNN) is proposed. Firstly, based on the Spark framework, a two-layer indexing structure based on grid and Voronoi diagram is constructed, and an efficient filtering and a refining processing algorithm are proposed. Secondly, the filtering step of proposed algorithm is used to obtain the candidates, and the refining step is used to remove the candidates. Finally, the candidate sets from different regions are merged to get the final result. Results of experiments on real-world datasets validate that the proposed method has better query performance and better stability and significantly improves the processing speed.

Digital twin of the management process of field service teams of an electric grid company

Modern electric grid companies are focused on minimum economically feasible costs and are aimed at improving the efficiency of financial and economic activities through the rational use of resources. The digital twin structure is proposed for the management of field service teams in the event of accidents and technological failures in an electric grid company. The digital twin includes an agent model, a system dynamics model, a geographic information system component, and modules with experiments. The description of the simulation model of management of field service teams in the event of accidents and technological failures is formalized, the input and output information on the model components is highlighted, the information is structured, and the scheme of the system dynamics model is created. Experiment designs for the digital twin of the management of field service teams in the event of accidents and technological failures in order to determine the best reliability and cost indicators are developed. The developed approach can be used to create digital twins of the management process of field service teams in the event of accidents and technological failures for various electric grid companies by selecting the parameters of simulation models according to the statistical reports by electric grid companies and connecting the appropriate GIS modules.

Spatial site selection for a centralized treatment center of livestock excreta: Taking Nantong Town as an example

At present, processing substantial livestock excreta produced by numerous concentrated small–middle-type livestock farms (SMLFs) has been a major problem of livestock farm owners and government departments. To solve this problem, this study established a suitability evaluation system for the spatial layout of a centralized treatment center of livestock excreta (CTCLE). On this basis, combined with the collection points of livestock excreta (CPLEs) determined by spatial clustering algorithm and median center and matched farmlands, the spatial site selection of CTCLE was analyzed using the geographic information system (GIS) spatial analysis method and GIS component development technology. Practical application research was conducted in Nantong Town, and pigs were used as examples. Results showed that most regions of Nantong Town belong to forbidden and unsuitable regions, accounting for 68.63% of the total region of the town. A small part of a highly suitable region (6.428 ha) was determined as potential CTCLE. A total of 839 SMLFs were divided into 61 CPLEs, and the spatial relation between potential CTCLEs and farmlands was established. The spatial sites of 11 CTCLEs in Nantong Town, Minhou County were selected, and the total nitrogen and phosphorus of livestock excreta to be reduced were estimated. The results will provide a scientific basis for the utilization of livestock excreta and the spatial layout planning of livestock and poultry breeding.

Application of geoinformation systems to ensure sustainable development of the city transport system

Population increase and urbanization of cities in all countries in recent decades, therefore, ensuring the development of the urban environment has become an important and relevant issue. The article considers the possibility of using a geographic information system (GIS) to ensure the functioning of the city’s transport systems and the selected basic tools of spatial analysis: transport accessibility of the area, air pollution (emissions), noise pollution, energy consumption, route and transport network, traffic and transport network infrastructure. The main components of GIS in the field of transport are analyzed. In addition, it uses methods for collecting, researching, synthesizing, analyzing, evaluating and presenting data on the transport environment of the city. The development of the urban environment is associated with the creation of transport systems that require large costs for movement and economic feasibility.

GIS methods for inventory of pacific salmons spawning grounds in the Amur River

Inventory of spawning grounds is an important tool for estimation of pacific salmons abundance and adequate management of their stocks. A set of the most up-to-date, relevant and effective methods based upon geographic information system (GIS) is substantiated, designed, developed and scheduled to implementation for inventory of the spawning grounds in the Amur basin. Abilities of GIS-technologies for optimization of the surveys planning and conducting and for processing, analysis, visualization and presentation of their results due to accelerated, simplified and enhanced workflow are shown. Three components of modern corporative GIS are presented: server, desktop and mobile ones. The system is partially loaded with the data about spawning grounds, tested for the basic operations as data collection, multi-user editing, geoprocessing, spatial analysis, cartographic visualization, protected web publication, etc., and adjusted and improved using the results of this testing for further implementation in complex fisheries surveys in the Amur River basin. Proposed GIS-technology is modifiable and scalable, so can be spread to other species and areas after appropriate modification; the GIS can be specialized for certain practical tasks.

Geographic Information System for Waste Management for the Development of Smart City Governance

The Era of the Industrial Revolution 4.0 has been able to change the paradigm of government towards the contribution of Information Technology in providing fast, precise and accurate services to the public for better information service needs. Trends in Smart City Governance will also increase public and government participation in utilizing application data so that they can provide suggestions and criticisms quickly, easily and accurately. Makassar has a population of 1,469,601 people and is the highest compared to other regions in South Sulawesi. Makassar has produced around 1,200 tons of waste per day that goes to Tamanagappa landfills. Waste generated by each district is different from other districts, so it is necessary to do integrated waste management. To overcome this problem, Makassar City Government applies the Smart City concept that focuses on Smart Environment. This concept aims to reduce and utilize waste and create better energy sources. The research objective is to develop a system that can provide information to the public so that the performance of the Makassar City Sanitation Office becomes effective and integrated. Geographic Information System (GIS) is a system designed to capture, store, manipulate, analyze, organize and display all types of geographic data. GIS components consist of data, software, hardware, users, and applications. Research using the Spiral method with tools or applications used by implementing ArcView, ArcGis, and Map Info. GIS tools used are based on Open Source such as Google Maps by providing various types of libraries that can be directly used. The results showed 90% of respondents agreed that this application could be used.

Semiautomated Metamorphic Testing Approach for Geographic Information Systems: An Empirical Study

A geographic information system (GIS) provides basic location-enabled services for many different applications related to navigation, education, and telecommunications. It is a foundation for analysis and visualization. Testing GIS is critical, but challenging due to the difficulty to assess the correctness of GIS outputs, which is called the test oracle problem of software testing. Metamorphic testing alleviates the problem by constructing metamorphic relations (MRs) among multiple inputs and outputs of the program under test. In this article, a semiautomated metamorphic testing (SAMT) method, based on the formal MR model and an improved adaptive random testing algorithm, was proposed to the GIS. To evaluate the performance of our approach, we conducted a case study on a superficial area calculation program, a typical component of GIS. Six kinds of MR construction methods were suggested for the GIS domain program testing. The experimental results show that SAMT can detect the mutations effectively that could solve the test oracle problem efficiently. More importantly, there is no need to manual participation in the testing process, except for the MR construction.

TOWARDS THE AUTOMATIC DETECTION OF GEOSPATIAL CHANGES BASED ON DIGITAL ELEVATION MODELS PRODUCED BY UAV IMAGERY

Abstract. Reliable and accurate geospatial-databases (Digital Elevation Models, DEMs) are an essential component of Geographic Information Systems (GIS). One of their most important uses is change detection – an invaluable tool for environmental interpretation and evidence-based action. High-performance and inexpensive Unmanned Aerial Vehicles (UAVs) are increasingly used for the acquisition of timely geospatial information (imagery) for the production of DEMs for geospatial change detection. DEMs produced from UAV imagery have very high resolution and very good internal accuracy. However, their absolute location accuracy is inferior to other mapping technologies. Therefore, existing change detection methods, which are based on the point-by-point comparison, will perform poorly when processing DEMs created from UAV imagery since they are limited in reliably separating real physical changes from artifacts related to DEM inherent inaccuracy or errors. This paper presents a novel methodology that overcomes these deficiencies, by implementing a hierarchical analysis and modeling process, in which a sequence of methods is used to automatically identify and match unique homological features, such as building corners or topographic maxima, in the various height models. These provide geospatial anchors that bring out local geospatial discrepancies between the models. Those are then used to "repair" (align) the models to the same geospatial reference system, at which point change-detection is performed. Experimental results showed that when calculating point-by-point height differences, 98.99% of the area was falsely classified as changed, whereas implementing our method adequately detected all the actual changes in the area with no false positives, correctly classifying 0.16% of the area as changed.

Mapping Violent Presence of Armed Actors in Colombia

Abstract. Heat maps and Early Warning Systems have traditionally contributed to identifying and managing risks associated with crime trends, health hazards, and natural disasters. However, their application to analyzing civil war dynamics still is at an early stage. To address this need, this research integrates Natural Language Processing (NLP) tools and Geographic Information Systems (GIS) to generate an interactive map of the violent presence of armed actors in the Colombian civil war between 1988 and 2017. The NLP component generates fine-grained geo-location data of armed actors' violent presence. The GIS component then uses the geo-referenced data to present dynamic clusters of four main types of actors: Government forces, Insurgent organizations, Paramilitary groups, and Criminal organizations. Each type of actors is further disaggregated into a multitude of specific armed organizations. Based on anomalies in the spatio-temporal trends identified in the data, we develop an EWS methodology to detect “emerging”, “intense”, and “critical” cases. This application contributes to the efforts of the academic and policy communities to understanding the spatio-temporal dynamics of political violence and promoting sustainable peace in civil war settings.

Memphis FitKids: implementing a mobile-friendly web-based application to enhance parents\u2019 participation in improving child health

BackgroundChild obesity is a major public health challenge, increasing the risk of chronic medical conditions such as type 2 diabetes, metabolic syndrome, and hypertension. Among U.S. states, Tennessee has one of the highest rates of child obesity. Emerging communication technologies can help to deliver highly disseminable population-level interventions to improve health behavior. The aim of this paper is to report the implementation and the evaluation of the reach of Memphis FitKids, a web-based application, intended to promote healthy behaviors for families and children.MethodsA community-level demonstration project, Memphis FitKids, was developed and implemented in Tennessee’s Greater Memphis Area. This application (www.memphisfitkids.org) was designed for parents to assess their children’s obesity risk through determinants such as weight, diet, physical activity, screen time, and sleep adequacy. A built-in “FitCheck” tool used this collected information to create a report with tailored recommendations on how to make healthy changes. A Geographic Information Systems component was implemented to suggest low-cost neighborhood resources that support a healthy lifestyle. A social marketing framework was used to develop and implement FitKids, and a Community Advisory Board with representatives from community partners (e.g., the YMCA of Memphis, the Pink Palace Family of Museums, and the Memphis Public Library) supported the implementation of the project. Five kiosks distributed in the community served as public access points to provide a broad reach across socioeconomic strata. Presentations at community events and the use of Facebook facilitated the promotion of FitKids. Website traffic and Facebook usage were evaluated with Google Analytics and Facebook Insights, respectively.ResultsIn Tennessee, 33,505 users completed 38,429 FitCheck sessions between July 2014 and December 2016. Among these, 6763 sessions were completed at the five kiosks in the community. FitKids was presented at 112 community events and the social media posts reached 23,767 unique Facebook users.ConclusionsThe Memphis FitKids demonstration project showed that web-based health tools may be a viable strategy to increase access to information about healthy weight and lifestyle options for families. Mobile-friendly web-based applications like Memphis FitKids may also serve health professionals in their efforts to support their clients in adopting healthy behaviors.

Computational implementation of a GIS developed tool for prediction of dynamic ground movement and deformation due to underground extraction sequence

In the last century, there has been a significant development in the evaluation of methods to predict ground movement due to underground extraction. Some remarkable developments in three-dimensional computational methods have been supported in civil engineering, subsidence engineering and mining engineering practice. However, ground movement problem due to mining extraction sequence is effectively four dimensional (4D). A rational prediction is getting more and more important for long-term underground mining planning. Hence, computer-based analytical methods that realistically simulate spatially distributed time-dependent ground movement process are needed for the reliable long-term underground mining planning to minimize the surface environmental damages. In this research, a new computational system is developed to simulate four-dimensional (4D) ground movement by combining a stochastic medium theory, Knothe time-delay model and geographic information system (GIS) technology. All the calculations are implemented by a computational program, in which the components of GIS are used to fulfill the spatial–temporal analysis model. In this paper a tight coupling strategy based on component object model of GIS technology is used to overcome the problems of complex three-dimensional extraction model and spatial data integration. Moreover, the implementation of computational of the interfaces of the developed tool is described. The GIS based developed tool is validated by two study cases. The developed computational tool and models are achieved within the GIS system so the effective and efficient calculation methodology can be obtained, so the simulation problems of 4D ground movement due to underground mining extraction sequence can be solved by implementation of the developed tool in GIS.

True orthoimage generation by mutual recovery of occlusion areas

Demand for orthoimages is increasing as a crucial component of geographic information systems (GISs). Orthoimages are geometrically equivalent to planimetric maps, which show true geographic locations of terrain features. To produce orthoimages, geometric distortions from camera tilt and relief displacement from perspective images must be corrected. Traditionally, removing such distortions has been accomplished by differential rectification in a pixel-by-pixel fashion. However, this method cannot produce true orthoimages because of the double-mapping problem. We propose a method of generating patch-based true orthoimages for surface patches in buildings. The proposed method utilizes three-dimensional (3D) building model data. Patches from the data were projected onto aerial images to extract image patches and analysis of the superstructures was performed. Because orthoimages are generated for each building, the orthoimage quality is enhanced when using building data with a high level of detail. Instead of performing the complex visibility analysis of existing approaches, this article identifies occlusion areas based on unit surfaces of buildings and presents mutual recovery of occlusions using multiple images. To evaluate the feasibility of the method, experiments were performed with real datasets: (1) a building with a dome superstructure, (2) high-rise buildings close to each other, and (3) buildings with various shapes.

Built Environment And Physical Activity In Urban Delhi: The Carrs-Gis Study

Objective Cardiometabolic diseases (CMD) are a major cause of mortality and morbidity worldwide. Among South Asians the onset is at a much younger age and involves all sections of the society. A major risk factor for CMD is inadequate physical activity (PA). 'Built environment' plays an important role in influencing participation in PA. However, the relationship between neighbourhood built environment and PA has been sparsely investigated in Low and Middle Incomes Countries. The primary objective of the present study was to objectively assess and study the relationship between Physical activity and Built environment in Urban Delhi. Method The Geographical Information System component of the Centre for Cardiometabolic Risk Reduction for South Asia Surveillance study (CARRS-GIS study) carried out in 3 major South Asian cities; New Delhi, Chennai and Karachi aims to study the relationship between built environment, CMD and their risk factors in South Asia. We located all study households; neighbourhood built environment features and performed GIS analysis of participant data overlaid on geographic data. PA data was measured using a culturally adapted version of the International Physical Activity Questionnaire and transformed to Metabolic Equivalent Task scores. Cluster analysis was carried out using the hotspot tool in ArcGIS. Results As part of the study we geocoded 8423 households from 350 clusters. Preliminary analyses from Delhi show a mixed picture with varying levels of PA in study neighbourhoods. Cluster analysis revealed statistically significant hot and cold spots. High physical activity clusters (hotspots) seemed to have better access to green and open spaces. PA Coldspots were found to be hotspots of higher than average Systolic Blood Pressure and Fasting Blood Glucose levels. Conclusion Exploratory spatial analysis shows that physical activity is related to neighbourhood built environment and other CMD risk factors in urban Delhi.

Effect of temperature on the phenology of Chilo partellus (Swinhoe) (Lepidoptera, Crambidae); simulation and visualization of the potential future distribution of C. partellus in Africa under warmer temperatures through the development of life-table parameters.

Maize (Zea mays) is a major staple food in Africa. However, maize production is severely reduced by damage caused by feeding lepidopteran pests. In East and Southern Africa, Chilo partellus is one of the most damaging cereal stem borers mainly found in the warmer lowland areas. In this study, it was hypothesized that the future distribution and abundance of C. partellus may be affected greatly by the current global warming. The temperature-dependent population growth potential of C. partellus was studied on artificial diet under laboratory conditions at six constant temperatures (15, 18, 20, 25, 28, 30, 32 and 35°C), relative humidity of 75±5% and a photoperiod of L12:L12h. Several non-linear models were fitted to the data to model development time, mortality and reproduction of the insect species. Cohort updating algorithm and rate summation approach were stochastically used for simulating age and stage structure populations and generate life-table parameters. For spatial analysis of the pest risk, three generic risk indices (index of establishment, generation number and activity index) were visualized in the geographical information system component of the advanced Insect Life Cycle modeling (ILCYM) software. To predict the future distribution of C. partellus we used the climate change scenario A1B obtained from WorldClim and CCAFS databases. The maps were compared with available data on the current distribution of C. partellus in Kenya. The results show that the development times of the different stages decreased with increasing temperatures ranging from 18 to 35°C; at the extreme temperatures, 15 and 38°C, no egg could hatch and no larvae completed development. The study concludes that C. partellus may potentially expands its range into higher altitude areas, highland tropics and moist transitional regions, with the highest maize potential where the species has not been recorded yet. This has serious implication in terms of food security since these areas produce approximately 80% of the total maize in East Africa.

The Method to Display the Distribution of Groundwater Pollution Dynamically with COMGIS Based on Visual Developing Platform

Groundwater pollution shold be visulazed by spatial maps, in order to know how the spatial pollutant situation is, the visualization analysis is adopted to analyse the regional pollution with monitoring data. Map is a visual means of symbolic expression to map data, ArcObjects provides a number of symbolic objects to render thematic maps, and these component objects are consisted with three series of Color, Symbol and Renderer. On the development platform C#.NET, taking geographic information system components (COMGIS), the thematic map program is designed and implemented by C# language and Arc Objects component, which is run correctly, thematic maps can be loaded to display the legend, and the grade levels number can be calculated automatically and set by user freely.

An oil spill surveillance program for Lake Pontchartrain

This article describes an oil spill surveillance strategy implemented in response to BP's 2010 MC252 oil well blowout in the Gulf of Mexico. A three-pronged strategy consisted of Geographic Information System (GIS) monitoring of the surface slick, hydrodynamic modeling of the potential movement of the slick within the Basin, and weekly field reconnaissance. Our analysis was completed in near real time during the event and the results and predictions helped local responders minimize oiling impacts in Lake Pontchartrain. No prior planning was undertaken before this crisis response, and this article reports our support activities as they happened. For the GIS component, a remote sensing derived surface slick outline layer was obtained to produce near daily maps showing the slick's proximity to Lake Pontchartrain along with weather conditions and deployed response assets. This regular monitoring of the slicks' location was complemented by hydrodynamic numerical modeling that simulated the currents that determined the trajectories of oil particles. These data were ground-truthed through weekly reconnaissance trips that assessed the potential routes of oil penetration into Lake Pontchartrain for the presence of sheen, tarballs, and other oil constituents. Despite the ad hoc design and on-the-fly implementation, these three assessments provided consistent and actionable information.

A characteristic bitmap coding method for vector elements based on self-adaptive gridding

Spatial index is a key component of Geographic Information Systems (GISystems). To date, an increasing number of spatial indexes have been developed to enhance the efficiency of spatial analysis and spatial query. Approximate expressions are adopted in the foundation of spatial index construction, to assist data organisation, e.g., bounding box of vector elements can be employed to build R-tree index. However, R-tree index using such bounding box expresses elements approximately, which usually results in redundancy and excessiveness due to inherent roughness of this method. This study proposes a characteristic bitmap coding method, termed the QCODE method, which generates approximate expressions of vector elements based on self-adaptive gridding. Based on the sizes of vector elements, this method selects the grid at an appropriate level in a self-adaptive manner, discretises the vector elements into grids through a rasterisation operation, as well as compresses and encodes this information as the code of a characteristic bitmap, i.e., the QCODE. The ‘bit’ data type is used in the design of QCODE to restrict the approximate expression of vector elements into finite bytes, providing more precise filtering as compared to the case in which only bounding box is used. With its distinct characteristics, the QCODE is introduced for the improvement of R-tree index. The results of experiments show that, combined with R-tree index, this method can reduce the filtering amount of vector elements as required for spatial analysis, and accelerate the execution efficiency of the entire process of GIS spatial analysis.

Spatial Analysis for Groundwater Pollution Based on Monitoring Data by COMGIS

Groundwater pollution is an important issue in recent years, in order to know how the spatial pollutant situation is, the visualization analysis is adopted to analyse the regional pollution with monitoring data. Monitoring data can be easily acquired, which is the basis for spatial analysis, with the GIS software, the vector layer of monitoring data can be established, and environmental pollution monitoring data can be dynamically managed by point vector layer. On the development platform VB.NET, taking geographic information system components (COMGIS) to design and develop software to come true the spatial analysis function, with the design techniques, various space interpolation methods can be loaded to realize the spatial analysis, such as IDW, Krige, Spline, Trend. These methods can be used to acquire the data of unknown pollutant region by loading the monitoring data layer. With the spatial interpolation method, visual spatial analysis function for groundwater pollution can be realized easily with monitoring data.

A geostatistical approach to spatial density distributions of sika deer (Cervus nippon)

Sika deer (Cervus nippon) cause serious damage to trees in Japanese forests. Browsing, bark stripping, and tree abrasion with antlers account for 50% of total wildlife damage over the past decade. The extent of forest damage depends on deer population density. We determined the spatial distribution of sika deer population density on Mt. Hiko (Fukuoka Prefecture, southwestern Japan). We also investigated changes in population density distribution over time. Determinants of population density were examined, with particular emphasis on the hunting cull. Deer densities in 1999 and 2004 were estimated by fecal pellet counts at 86 sites. We used kriging, a geostatistical technique that is a component of geographic information systems, to interpolate site-specific point data over large areas of landscape. Mapping procedures showed that high-density (≥30.0 deer km−2) and low-density sections of landscape (≤10.0 deer km−2) decreased in areal extent between 1999 and 2004. Contractions of high-density sections were attributable to intensive hunting. In low-density landscape sections, reduced hunting pressure allowed increased persistence of adult animals whose high fecundity led to population growth and higher deer densities. Landscape tracts with medium deer densities (10.0–30.0 deer km−2) expanded, adding further difficulties to the task of wildlife management. Given the scale of the problems caused by deer, it is clear that reliable estimates of population size across space and time are essential components of the wildlife manager's toolbox.

Surveying general prospects and challenges of GIS implementation in developing countries: a SWOT–AHP approach

We propose a combined method based on the strengths, weaknesses, opportunities and threats (SWOT) and analytic hierarchy process (AHP) to investigate the challenges and prospects of adopting geographic information systems (GIS) in developing countries. In this context, we identify, group, and analyse SWOT indicators in relation to the main GIS components: data, people, and technology. The relative significance of each SWOT indicator and its related SWOT groups in each GIS component is quantified. The method is then applied in a situation assessment of GIS adoption in the governmental organisations and strategic planning. The SWOT–AHP approach proves to be very useful in identifying and quantifying the relative significance of the major factors affecting GIS implementation, and effectively facilitates GIS strategic planning.