97 research outputs found
Discovering the spatial coverage of the documents through the SpatialCIM Methodology.
The main focus of this paper is to present the SpatialCIM methodology to identify the spatial coverage of the documents in the Brazilian geographic area. This methodology uses a linguistic tool to assist in the entity recognition process. The linguistic tool classifies the recognized entities as person, organization, time and localization, among others. The localization entities are checked using a geographic information system (GIS) in order to extract the Brazilian entity geographic paths. If there are multiple geographic paths for a single entity, the disambiguation process is carried out. This process attempts to locate the best geographic path for an entity considering all the geographic entities in the text. Another important objective of this paper is to show that the disambiguation process improves the geographic classification of the documents considering the obtained geographic paths. The validation process considers a set of news previously labeled by an expert and compared with the results of the disambiguated and non-disambiguated geographic paths. The results showed that the disambiguation process improves the classification compared with the classification without disambiguation. Keywords: Ambiguity problem resolution, spatial coverage identification, toponym resolution
The SpatialCIM methodology for spatial document coverage disambiguation and the entity recognition process aided by linguistic techniques.
Abstract. Nowadays it is becoming more usual for users to take into account the geographical localization of the documents in the retrieval information process. However, the conventional retrieval information systems based on key-word matching do not consider which words can represent geographical entities that are spatially related to other entities in the document. This paper presents the SpatialCIM methodology, which is based on three steps: pre-processing, data expansion and disambiguation. In the pre-processing step, the entity recognition process is carried out with the support of the Rembrandt tool. Additionally, a comparison between the performances regarding the discovery of the location entities in the texts of the Rembrandt tool against the use of a controlled vocabulary corresponding to the Brazilian geographic locations are presented. For the comparison a set of geographic labeled news covering the sugar cane culture in the Portuguese language is used. The results showed a F-measure value increase for the Rembrandt tool from 45% in the non-disambiguated process to 0.50 after disambiguation and from 35% to 38% using the controlled vocabulary. Additionally, the results showed the Rembrandt tool has a minimal amplitude difference between precision and recall, although the controlled vocabulary has always the biggest recall values.GeoDoc 2012, PAKDD 2012
A survey on the geographic scope of textual documents.
Recognizing references to places in texts is needed in many applications, such assearch engines,loca-
tion-based social media and document classification. In this paper we present a survey of methods and
techniques for there cognition and identification of places referenced in texts. We discuss concept sand
terminology, and propose a classification of the solutions given in the literature. We introduce a
definition of the Geographic Scope Resolution (GSR) problem, dividing it in three steps: geoparsing,
reference resolution, and grounding references. Solutions to the first two steps are organized according
to the method used, and solutions to the third step are organized according to the type of out put produced. We found that it is difficult to compare existing solutions directly to one another, because they
of ten create their own bench marking data, targeted to their own problem
Geospatial database generation from digital newspapers: use case for risk and disaster domains.
Dissertation submitted in partial fulfilment of the requirements for the Degree of Master of Science in Geospatial Technologies.The generation of geospatial databases is expensive in terms of time
and money. Many geospatial users still lack spatial data. Geographic
Information Extraction and Retrieval systems can alleviate this problem.
This work proposes a method to populate spatial databases automatically
from the Web. It applies the approach to the risk and disaster domain
taking digital newspapers as a data source. News stories on digital
newspapers contain rich thematic information that can be attached
to places. The use case of automating spatial database generation is
applied to Mexico using placenames. In Mexico, small and medium
disasters occur most years. The facts about these are frequently mentioned
in newspapers but rarely stored as records in national databases.
Therefore, it is difficult to estimate human and material losses of those
events.
This work present two ways to extract information from digital news
using natural languages techniques for distilling the text, and the national
gazetteer codes to achieve placename-attribute disambiguation.
Two outputs are presented; a general one that exposes highly relevant
news, and another that attaches attributes of interest to placenames.
The later achieved a 75% rate of thematic relevance under qualitative
analysis
Enhancing Road Infrastructure Monitoring: Integrating Drones for Weather-Aware Pothole Detection
The abstract outlines the research proposal focused on the utilization of Unmanned Aerial Vehicles (UAVs) for monitoring potholes in road infrastructure affected by various weather conditions. The study aims to investigate how different materials used to fill potholes, such as water, grass, sand, and snow-ice, are impacted by seasonal weather changes, ultimately affecting the performance of pavement structures. By integrating weather-aware monitoring techniques, the research seeks to enhance the rigidity and resilience of road surfaces, thereby contributing to more effective pavement management systems. The proposed methodology involves UAV image-based monitoring combined with advanced super-resolution algorithms to improve image refinement, particularly at high flight altitudes. Through case studies and experimental analysis, the study aims to assess the geometric precision of 3D models generated from aerial images, with a specific focus on road pavement distress monitoring. Overall, the research aims to address the challenges of traditional road failure detection methods by exploring cost-effective 3D detection techniques using UAV technology, thereby ensuring safer roadways for all users
Comparative Study of GIS and Conventional Household Survey Sampling Methods: Feasibility, Cost and Family Planning Coverage Estimates
Background
Household surveys serve as the main source of data on reproductive, maternal, and child health in low and middle-income countries (LMICs). Considering their significant role, ensuring production of high-quality data is imperative. However, the high costs associated with conducting large-scale surveys in LMICs has led to a search for alternative survey sampling methods. This study compared two probability sampling methods: geographic information system (GIS) and conventional sampling. It assessed feasibility of GIS sampling, evaluated equivalence of sampling methods for selected family planning (FP) coverage indicators, and compared implementation costs.
Methods
Concurrent cross-sectional surveys using the two sampling methods were implemented in the same 150 clusters in Burkina Faso. For GIS method, free satellite images were used to digitize cluster boundaries and potentially residential structures. Feasibility was assessed using embedded mixed methods. Equivalence threshold (+/- 5 percentage points) to compare FP indicators was defined using confidence interval (CI) approach. Costs were estimated using micro-costing from international donor’s perspective. Average and incremental costs-per-cluster and costs-per-completed-interview were calculated.
Results
In conventional method, 14,610 households were enumerated; 3,021 households sampled. In GIS method, 58,120 structures were digitized; 3,371 households sampled. There was no statistically significant difference in the survey response rates for occupied dwellings among the two sampling methods (p=0.089). Qualitative results documented the advantages and challenges experienced during implementation of GIS method.
Of the 9,907 eligible women selected, 4,370 were in conventional method, 3,913 in GIS and 1,624 in both methods. The CIs of sociodemographic variables and FP indicators overlapped across both methods. Sampling methods yielded equivalent estimates of modern contraceptive prevalence and unmet need for FP. Cost difference between the methods was 266 and 13 and $4 less per completed interview, in the urban and rural areas, respectively.
Conclusion
Using GIS for large-scale, probability-based household surveys is feasible in both urban and rural settings, if recent, high-resolution satellite images are available. It should be considered a valid alternative for deriving unbiased population coverage estimates in resource-constrained settings
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Extracting Computational Representations of Place with Social Sensing
Place-based GIS are at the forefront of GIScience research and characterized by textual descriptions, human conceptualizations as well as the spatial-semantic relationships among places. The concepts of places are difficult to handle in geographic information science and systems because of their intrinsic vagueness. They arise from the complex interaction of individuals, society, and the environment. The exact delineation of vague regions is challenging as their borders are vague and the membership within a region varies non-monotonically and as a function of context. Consequently, vague regions are difficult to handle computationally, e.g., in spatial analysis, cartography, geographic information retrieval, and GIS workflows in general. The emergence of big data brings new opportunities for us to understand the place semantics from large-scale volunteered geographic information and data streams, such as geotags, texts, activity streams, and GPS trajectories. The term "social sensing" describes such individual-level big geospatial data and the associated analysis methods. In this dissertation, I present a generalizable, data-driven framework that complements classical top-down approaches by extracting the representations of vague cognitive regions and function regions from bottom-up approaches using spatial statistics and machine learning techniques with various social sensing sources. I demonstrate how to derive crisp boundaries for cognitive and functional regions from points of interest data, and show how natural language processing techniques can enrich our understanding of places and form a foundation for the semantic characterization of place types and the generalization of regions. This work makes contributions to the development of computational methodologies for extracting vague cognitive regions and functional regions using data-driven approaches as well as the novel semantic generalization processing technique
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Detecting the Presence of Disease by Unifying Two Methods of Remote Sensing.
There is currently no effective tool available to quickly and economically measure a change in landmass in the setting of biomedical professionals and environmental specialists. The purpose of this study is to structure and demonstrate a statistical change-detection method using remotely sensed data that can detect the presence of an infectious land borne disease. Data sources included the Texas Department of Health database, which provided the types of infectious land borne diseases and indicated the geographical area to study. Methods of data collection included the gathering of images produced by digital orthophoto quadrangle and aerial videography and Landsat. Also, a method was developed to identify statistically the severity of changes of the landmass over a three-year period. Data analysis included using a unique statistical detection procedure to measure the severity of change in landmass when a disease was not present and when the disease was present. The statistical detection method was applied to two different remotely sensed platform types and again to two like remotely sensed platform types. The results indicated that when the statistical change detection method was used for two different types of remote sensing mediums (i.e.-digital orthophoto quadrangle and aerial videography), the results were negative due to skewed and unreliable data. However, when two like remote sensing mediums were used (i.e.- videography to videography and Landsat to Landsat) the results were positive and the data were reliable
Applications of Internet of Things
This book introduces the Special Issue entitled “Applications of Internet of Things”, of ISPRS International Journal of Geo-Information. Topics covered in this issue include three main parts: (I) intelligent transportation systems (ITSs), (II) location-based services (LBSs), and (III) sensing techniques and applications. Three papers on ITSs are as follows: (1) “Vehicle positioning and speed estimation based on cellular network signals for urban roads,” by Lai and Kuo; (2) “A method for traffic congestion clustering judgment based on grey relational analysis,” by Zhang et al.; and (3) “Smartphone-based pedestrian’s avoidance behavior recognition towards opportunistic road anomaly detection,” by Ishikawa and Fujinami. Three papers on LBSs are as follows: (1) “A high-efficiency method of mobile positioning based on commercial vehicle operation data,” by Chen et al.; (2) “Efficient location privacy-preserving k-anonymity method based on the credible chain,” by Wang et al.; and (3) “Proximity-based asynchronous messaging platform for location-based Internet of things service,” by Gon Jo et al. Two papers on sensing techniques and applications are as follows: (1) “Detection of electronic anklet wearers’ groupings throughout telematics monitoring,” by Machado et al.; and (2) “Camera coverage estimation based on multistage grid subdivision,” by Wang et al
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