103 research outputs found

    Formal extension of the relational model for the management of spatial and spatio-temporal data

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    [Resumen] En los últioms años, se ha realizado un gran esfuerzo investigador en la manipulación de datos especiales y Sistemas de Información Geográfica (SIG). Una clara limitación de las primeras aproximaciones es la falta de integración entre datos geográficos y alfanuméricos. Para resolver esto surge el área de Bases de Datos Espaciales. Los problemas que aparecen en este campo son muchos y complejos. Un primer ejemplo son las peculiaridades de las operaciones espaciales, como el calculo de la intersección espacial de dos superficies. Otro ejemplo es el elegir las estructuras de datos apropiadas (relaciones, capas, etc.) y el conjunto de operaciones adeucado. La combinación con las Bases de Datos Temporales da lugar a las Bases de Datos Espacio-temporales, en las que la inclusión de la dimensión temporal complica más los problemas anteriores. A pesar de la gran cantidad de aproximaciones propuestas, no se ha llegado todavía a una solución satisfactoria. La presente tesis propone una nueva solución que resuelve todos los problemas de modelado de datos espaciales y espacio-temporales resaltados arriba. Parte del trabajo se completó durante el proyecto ""CHOROCRONOS"": A Research Network for Saptiotemporal Database Systems"", financiado por la Unión Europea. El modelo propuesto en la tesis define tres tipos de dato punto, línea y superficie, que encajan perfectamente en la percepción humana. La definición de estos tipos de dato se basa en la definición previa de Quanta Espacial. Las estructuras de datos usadas son las relaciones no anidadas de modelo relacional puro. El conjunto de operaciones relacionales permite alcanzar casi por completo la funcionalidad propuesta en otros modelos. Todas las operaciones han sido definidas en base a un núcleo reducido de operaciones primitvas. Todos los tipos de datos, espaciales, espacio-temporales y convencionales se manipulan de forma uniforme con este conjunto de operaciones

    Disturbance indicators for time series reconstruction and marine ecosystem health impact assessment

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    A systematic reconstruction of Multiple Marine Ecological Disturbances (MMEDs) involving disease occurrence, morbidity and mortality events has been undertaken so that a taxonomy of globally distributed marine disturbance types can be better quantified and common forcing factors identified. Combined disturbance data include indices of morbidity, mortality and disease events affecting humans, marine invertebrates, flora and wildlife populations. In the search for the best disturbance indicators of ecosystem change, the unifying solution for joining data from disparate fields is to organize data into space/time/topic hierarchies that permit convergence of data due to shared and appropriate scaling. The scale of the data selects for compatible methodologies, leading to better data integration, dine series reconstruction and the discovery of new relationships. Information technology approaches designed to assist this process include bibliographic keyword searches, data-mining, data-modeling and geographic information system design. Expert consensus, spatial, temporal, categorical and statistical data reduction methods are used to reclassify thousands of independent anomaly observations into eight functional impact groups representing anoxic-hypoxic, biotoxin-exposure, disease, keystone-chronic, mass-lethal, new-novel-invasive, physically forced and trophic-magnification disturbances. Data extracted from the relational database and Internet (http://www.heedmd.org) geographic information system demonstrate non-random patterns relative to expected dependencies. When data are combined they better reflect response to exogenous forcing factors at larger scales (e.g. North Atlantic and Southern Ocean Oscillation index scales) than is apparent without grouping. New hypotheses have been generated linking MMEDs to climate system forcing , variability and changes within the Northwestern Atlantic Ocean, Gulf of Mexico and Caribbean Sea. A more general global survey known collectively as the Health Ecological and Economic Dimensions (HEED) project demonstrates the potential application of the methodology to the Baltic Sea and other large marine ecosystems. The rescue of multi-decadal climatic, oceanographic, fisheries economic, and public health anomaly data combined with MMED data provides a tool to help researchers create regional disturbance regimes to illustrate disturbance impact. A recommendation for a central data repository is proposed to better coordinate the many data observers, resource managers, and agencies collecting pieces of marine disturbance information needed for monitoring ecosystem condition

    Publications from NIAS: January 1988-June 2013 (NIAS Report No. R23-2014)

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    This report has a bibliographic listing of all the publications from NIAS since inception till June 201

    LIPIcs, Volume 277, GIScience 2023, Complete Volume

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    LIPIcs, Volume 277, GIScience 2023, Complete Volum

    Faculty Publications and Creative Works 1997

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    One of the ways we recognize our faculty at the University of New Mexico is through this annual publication which highlights our faculty\u27s scholarly and creative activities and achievements and serves as a compendium of UNM faculty efforts during the 1997 calendar year. Faculty Publications and Creative Works strives to illustrate the depth and breadth of research activities performed throughout our University\u27s laboratories, studios and classrooms. We believe that the communication of individual research is a significant method of sharing concepts and thoughts and ultimately inspiring the birth of new of ideas. In support of this, UNM faculty during 1997 produced over 2,770 works, including 2,398 scholarly papers and articles, 72 books, 63 book chapters, 82 reviews, 151 creative works and 4 patents. We are proud of the accomplishments of our faculty which are in part reflected in this book, which illustrates the diversity of intellectual pursuits in support of research and education at the University of New Mexico. Nasir Ahmed Interim Associate Provost for Research and Dean of Graduate Studie

    Three Essays on Law Enforcement and Emergency Response Information Sharing and Collaboration: An Insider Perspective

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    This dissertation identifies what may be done to overcome barriers to information sharing among federal, tribal, state, and local law enforcement agencies and emergency responders. Social, technical, and policy factors related to information sharing and collaboration in the law enforcement and emergency response communities are examined. This research improves information sharing and cooperation in this area. Policing in most societies exists in a state of dynamic tension between forces that tend to isolate it and those that tend to integrate its functioning with other social structures (Clark, 1965). Critical incidents and crimes today cross jurisdictions and involve multiple stakeholders and levels. Law enforcement and emergency response agencies at federal, tribal, state, and local levels, including private sector entities, gather information and resources but do not effectively share this with each other. Despite mandates to improve information sharing and cooperation, gaps remain perhaps because there is no clear understanding of what the barriers to information sharing are. Information sharing is examined using a multi-method, primarily qualitative, approach. A model for information sharing is presented that identifies social, technical, and policy factors as influencers. Facets of General Systems Theory, Socio-technical Theory, and Stakeholder Theory (among others) are considered in this context. Information sharing is the subject of the first work of the dissertation: a theoretical piece arguing for use of a conceptual framework consisting of social, technical, and policy factors. Social, technology, and policy factors are investigated in the second essay. That essay introduces a new transformative technology, edgeware, that allows for unprecedented connectivity among devices. Social and policy implications for crisis response are examined in light of having technological barriers to sharing resources reduced. Human and other factors relevant to information sharing and collaboration are further examined through a case study of the Central New York Interoperable Communications Consortium (CNYICC) Network, a five-county collaboration involving law enforcement, public safety, government, and non-government participants. The three included essays have a common focus vis-à-vis information sharing and collaboration in law enforcement and emergency response. The propositions here include: (P1) Information sharing is affected by social, technical, and policy factors, and this conceptualization frames the problem of information sharing in a way that it can be commonly understood by government and non-government stakeholders. The next proposition involves the role of technology, policy, and social systems in information sharing: (P2) Social and policy factors influence information sharing more than technical factors (assuming it is physically possible to connect and/or share). A third proposition investigated is: (P3) Social factors play the greatest role in the creation and sustaining of information sharing relationships. The findings provide a greater understanding of the forces that impact public safety agencies as they consider information sharing and will, it is hoped, lead to identifiable solutions to the problem from a new perspective

    12th International Conference on Geographic Information Science: GIScience 2023, September 12–15, 2023, Leeds, UK

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    No abstract available

    Getting the Word Out: A Study of Assistance Information Made Available to Low-Income People through County Websites

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    Electronic government (e-government) is vetted as a mechanism to deliver government information and services to the public with efficiency, cost-effectiveness, and greater democratization. The impacts to low-income people can be significant but the topic remains largely unexplored by research. This new study establishes a research agenda to examine the social impacts (rather than the technology focus) of that space wherein assistance information is deployed digitally and a low-income person seeks and retrieves it. This dissertation examines how information about Medicaid, Supplemental Nutrition Assistance Program ("food stamps), and Temporary Assistance to Needy Families ("welfare") are delivered electronically. Case studies of three Maryland counties 1) examine information to understand what is made available on-line, 2) examine the state and county statutes, strategies, and policies issued on-line to understand expectations, requirements, and implementation decisions, and 3) compare implementations and alignment with statutory mandates. The research identified commonalities and gaps between the mandates and implementation. In particular, state statutes support delivering services and information digitally across multiple platforms. This is being implemented for some county services but notably, not for assistance services for low-income people. This obviates opportunities to reduce the stigma, effort, and costs in applying for services and for realizing greater efficiency in assistance delivery by Departments of Social Services. This gap perpetuates low-income people as a "separate but unequal" class, making this a question of civil rights, and issues of income and full-realized citizenship. This exploratory research provides a new lens through which to expand current information theory models such as information poverty, small worlds, and digital inclusion. It can help identify mechanisms to address. This research can help policymakers to address the intersection of technology; changes in demographics, technology access, and literacy; income; citizenship; biases designed into automation; and organization efficiency. Finally, it can help inform a practical framework with which counties can determine how closely program information and delivery meet public needs and evaluate the impacts of e-government
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