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[en] Over ten years ago, it was established that the most frequent reason that motivates a panel survey on transport studies is the evaluation of a change in the transportation system, or a specific transportation-planning project, especially when the project involves novel elements. From a statistical viewpoint, a panel survey has the definite advantage to offer more accurate estimatesof changes than cross-sectional surveys for the same sample size. Observing travel patterns of individuals and households overseveral consecutive days, has offered insights into activity scheduling and travel planning. Variability in travel patterns has important policy implications as well, but how much effort is worth to design a panel survey? To evaluate the effects of the transport policies introduced in Madrid during the last five years, a ‘short-long’ panel survey wasbuilt, based on a sample of a Madrid-worker subpopulation most affected by those recent changes in transport policy. The paper describes both the design and construction of the panel based on GPS technology, and presents some results based on an analysis of its two waves; for example, it registered an increment of public transport use and walking trips in 10%. The panel overcomes the known attrition problem thanks to providing incentives, maintaining contact, using the same interviewer for the same respondents, and conducting face-to-face interviews. (Author)
[en] Systems that allow users to store and retrieve spatial data, provide for analyses of spatial data, and offer highly detailed display of spatial data are referred to as geographic information systems, or more typically, GIS. Since their initial usage in the 1960s, GISs have evolved as a means of assembling and analyzing diverse data pertaining to specific geographical areas, with spatial locations of the data serving as the organizational basis for the information systems. The structure of GISs is built around spatial identifiers and the methods used to encode data for storage and manipulation. This paper examines how GIS has been used in typical environmental assessment, its use for cumulative impact assessment, and explores litigation that occurred in the United States Federal court system where GIS was used in some aspect of cumulative effects. The paper also summarizes fifteen case studies that range from area wide transportation planning to wildlife and habitat impacts, and draws together a few lessons learned from this review of literature and litigation.
[en] The IAEA Department of Safeguards is proposing a spatial data delivery process for state submission of site declaration maps. This new initiative is in support of the Department's Geospatial Exploitation System (GES) which utilizes spatial data from a multitude of sources to enable spatial analysis to verify declarations. Worldwide, many sites deliver declaration maps produced with spatially enabled technologies, such as Geographic Information Systems (GIS), however, the actual spatial data that enables the map production is absent. This paper will present how Bruce Power is using GIS to manage safeguard information for its site and why supporting the digital submission of spatial data to the IAEA, as part of the state declaration, both modernizes and simplifies the submission process while also supporting the objectives of the IAEA GES. (author)
[en] There is increasing focus on the role small-scale decentralised renewable energy developments could play in helping the UK meet its target of over 15% renewable energy by the year 2020 and alter energy behaviours through active community engagement. Upland areas are considered key areas where such community-based developments could occur due to their natural resources and range of community scales. This study uses GIS-based techniques to develop a methodology that assesses the regional-scale potential for community-based renewable electricity across Cumbria and whether a combination of these developments at the community-scale could make a significant contribution to local electricity consumption. This methodology looks at a range of technologies including hydro-power, wind-power, solar PV and bioenergy. The results suggest there is ample resource available for small communities by combining a mix of localised renewable electricity developments, which is highlighted through energy scenarios for a selected community. Further work will investigate whether this potential can be realised in reality by looking at resource resilience and community-level acceptability. - Highlights: ► A mix of wind, solar, bioenergy and hydro-power options are presented for Cumbria, UK. ► High resolution spatial analysis is conducted focussing on localised developments. ► Locations with sufficient renewable electricity potential were identified. ► Renewable options are explored further through a town case study. ► Scenarios consider different scales, mixes and contributions to local energy demand.
[en] The coordinate transforming of geography information system includes two kinds of transforming, map projection and coordinate-transforming. This paper proposed a arithmetic of coordinate-transforming, it implement the transforming between the longitude-latitude coordinate and the screen coordinate and apply it in the GIS. The preferable effect was made. (authors)
[en] This Technical Report concerns to some relevant concepts in Cartography and GIS. We will define terms and functions as scale, projection, cartographic syntaxes. We'll specify some Geographic Information, formats, sources... Finally, we will study about GIS applications and, specially, how CIEMAT is working with that, and what is the future of this technology. (Author) 71 refs
[en] In this work, we propose a hierarchical extension of the polygonality index as the means to characterize geographical planar networks. By considering successive neighborhoods around each node, it is possible to obtain more complete information about the spatial order of the network at progressive spatial scales. The potential of the methodology is illustrated with respect to synthetic and real geographical networks
[en] Water erosion is a major problem in the world; it results from the agricultural intensification, the climatic variations, the nature and use of soil. The study of erosion risk requires the understanding the factor from which he is influenced. So it facilitates the decision-making regarding the proper management and restoration of soils. Several studies on erosion in Tunisia have been made. The present study aims to develop an easy method, based on the integration of map data (administrative boundaries, soil layers) and statistical data (rainfall) in a GIS for the identification and mapping of vulnerable soils to erosion. The methodology used, was to retain and study the parameters of the relevant factors influencing the phenomenon (the erosivite of rainfall, the topographic index, the occupation of grounds and the soil erodibility). Then after a consolidation of individual parameters of these different factors, they have been folded under the ArcView GIS 3.2a as a model of vulnerability of soils previously established. The model established by a tree of entrance. He allows the crossing of five factors(mailmen) (the erosivite of the rain (R), pedological card(map) ( K ), card(map) of activity(occupation) of ground ( C ), digital model of the ground ( MNT), the factor(mailman) of arrangement(development) ( P )) in the tree of entered and this led to the realization of the erosion hazard map. Then the result of the erosion hazard is crossed to determine the soil loss map. The results were used to locate five classes of vulnerabilities of soil erosion (very low, low, medium, high and very high). These results are used to simulate water conservation management scenarios end the fight against erosion.
[en] This review paper is focused on groundwater level monitoring using levelogger and the importance of long-term groundwater level data. The levelogger provides an inexpensive and convenient method to measure level, temperature and conductivity all in one probe. It can provide real time view as data is being recorded by the connected data logger. Water-level measurements from observation wells are the principal source of information about the hydrologic stresses acting on aquifers and how these stresses affect ground-water recharge, storage, and discharge. Long-term and systematic measurements of water levels provide essential data needed to evaluate changes in the resource over time to develop ground-water models, forecast trends and monitor the effectiveness of groundwater management. A significant advantage of this method of data collection and reporting are the groundwater level data can be updated real time. The accessibility of water level data is greatly enhanced by the Geographic Information System (GIS) to visually illustrate the locations of observation wells relative to relevant topographic, geologic, or hydrologic features. GIS and internet greatly enhance the capability for retrieval and transmittal of water-level data to potential users. (author)
[en] Expansive soils can be categorized as one of the geohazards observed in the urban environment, representing a silent hazard to buildings and infrastructure. To evaluate this problematic soil it is necessary to know some of its geotechnical properties. Generally, the average values of soil properties are used in the methods which characterize the geological formation and the lithological group, which causes a great degree of uncertainty. To overcome this problem, this study proposes a procedure for estimating and modelling the principle soil properties that have an impact on expansive soils. The selected case study is located in the Hermanos Cruz neighbourhood in the city of Pinar del Rio in Cuba. The investigation was organized into the following stages: primary assessment of the potential expansiveness of the soils, modelling of the soil properties utilizing 3D geostatistical methods and finally the cartographic representation of the potential Expansiveness of soils on a Geographic Information System (GIS) platform at different depth zones which are of importance in the construction of shallow foundations of engineering works. The application of this methodology in the Hermanos Cruz neighbourhood revealed that its soils possess a potential expansiveness of low to medium, apart from some isolated zones which show a potential expansiveness of medium to high. (Author)