Size Of Spatial Units Research Articles

A real-time intelligent monitoring method for indoor evacuee distribution based on deep learning and spatial division

Providing real-time and detailed indoor evacuee distribution information is of great significance for the on-site formulating and dynamic adjustment of indoor emergency evacuation strategies. However, due to limitations in hardware costs and privacy protection, existing video surveillance and other evacuee counting methods cannot achieve real-time and accurate monitoring of the number and distribution of evacuees in all indoor areas. To solve the problem, using video data from an indoor surveillance system as a data source, an intelligent monitoring method for indoor pedestrian real-time distribution based on deep learning and spatial division is proposed. Firstly, the whole indoor area is divided many subareas according to the layout of indoor space and the size of spatial units. Then, deep learning detection and tracking algorithms are used to detect and track evacuees to achieve the number of evacuees at the boundary of each subarea and their movement directions; Finally, the numbers of evacuees entering and leaving each subarea are counted to obtain the spatial distribution information of evacuees. The experimental results show that within an appropriate monitoring distance, the proposed method achieves an average F1 score of 91.85% for evacuee counting at the boundaries of each subarea, with a processing speed of 22 FPS. More comprehensive and accurate real-time monitoring of evacuee distribution in the entire indoor space can be achieved, including no covered areas of cameras. It not only helps to formulate on-site emergency evacuation in case of a fire, but also enhances the daily operation and management capabilities of buildings.

How visually effective are animated cartograms? Potential improvements based on the example of segregation in Bogotá (1993-2005)

Cartograms have long been used to highlight the uneven distribution of a phenomenon over a given area. On these maps, the size of spatial units is proportional to their weight (the number of inhabitants, amount of CO2 emitted, etc.). Over the past twenty or so years, the benefits of adding movement to this type of map–mainly to assess changes over time and space–have been discussed. Several methods have been suggested for constructing animated cartograms, and efficient algorithms are now available to distort spatial units. Nevertheless, rendering a second variable on an animated cartogram remains a challenge, generally giving rather poor results. In this article we experiment with a way of improving the effectiveness of such animated cartograms, by conjointly using spatial smoothing. We demonstrate the potential of combining these two mapping techniques in animated mode to visualize changes in socio-residential segregation over time, using the example of Bogotá (Colombia) from 1993 to 2005.

Do the size and shape of spatial units jeopardize the road mortality-risk factors estimates?

We aimed to evaluate the role of spatial units with different shapes and sizes on road-kill modeling for small vertebrate species. We used the road-kill records of two reptiles, water snake (Helicops infrataeniatus) and D’Orbigny's slider turtle (Trachemys dorbigni), and three mammals, white-eared opossum (Didelphis albiventris), coypu (Myocastor coypus) and Molina's Hog-nosed skunk (Conepatus chinga). Hierarchical partitioning was used to evaluate the independent influence of different land-use classes on road-kill by varying the shape and size of the spatial units. Variables that most explained road-kill were consistent over the different spatial unit types. The standard size seemed to be a reasonable solution for these species. Prior analysis with several sizes and shapes is needed to identify the appropriate spatial unit to model road-kill occurrence for larger vertebrates with different history traits.

Methodological Issues in Cross-Border Analyses of European Small-Area Data: A Case Study

The growing trends for political and economic integration within the European Union signal a need for improved cohesion of national data sets to allow for comparative cross-national research on socioeconomic topics. Difficulties in achieving comparability of variables and spatial bases can apply whether analysis is undertaken at the most macro level (that of entire nations) or at more micro spatial scales. In this paper we will discuss the methodological problems which can arise from comparative cross-border analysis by using small-area census data within Ireland (North and South) as illustration. As this analysis demonstrates, limited overlap between the specific variables in national data sets, different national contexts for socioeconomic indicators, and variations between data sets in the size of spatial units can all cause analytical problems at this spatial scale. In particular, scale mixing can potentially result in very misleading interpretations. Possible solutions to these problems are discussed, and policy recommendations are made in relation to microscale spatial data sets at the national, as well as at the pan-European, level.

Paleomagnetic Study in a Folded Zone of Hsuehshan Range,Northeastern Coast of Taiwan

The spatial variation of the fractal dimension and its geologic implicationsare studied using an empirical approach.The fractal parameters,including the surface's fractal dimension,D(subscript surf),the angular fractal dimension,D(subscript ang),the gamma(γ)value and the break-distance(R),are derived bythe variogram method.Synthetic surfaces are generated by the successiverandom addition(SRA)method by assigning different values to the Hurstexponent.Two test sites were selected to study the link between the fractalparameters and the geologic features.The following conclusions can bedrawn from this research:(1)The fractal parameters of a landscape surfaceare region-dependent and scale-dependent.The spatial distribution offractal parameters should be studied in a suitable size of spatial unit.(2)The angled variogram method can readily disclose the anisotropic natureof a landscape surface.(3)The surface's fractal dimension reflects the litho-logic variations underlying a landscape surface,and the gamma value reflectsthe topographic relief of the surface.(4)The mean direction and thevector resultant of angular fractal dimensions have a close relation withthe major geological structures of the landscape.

Locating objects and communicating about locations: Organizational differences in children's searching and direction-giving.

Two studies examined spatial organization reflected in searches for objects and descriptions of locations. Six-year-olds and adults retrieved objects hidden on the floors of a house or directed another person about how to retrieve them. Of particular interest was whether children's searches and directions reflected clustering of locations by floors. Six-year-olds' searches were more organized than their directions, but a follow-up study demonstrated that they could produce organized directions if prompted. Analyses of the content and structure of spatial information in directions indicated that children and adults communicated the information in an order of decreasing size of spatial unit. Results are discussed in terms of factors underlying spatially organized searching and directiongiving. Locating objects and places is a practical task that occupies a great deal of everyday human and animal behavior. A major concern of infants and young children, for example, is finding and maintaining proximity to their primary caregiver (Carr, Dabbs, & Carr, 1975). Adults also spend a considerable amount of time searching for valued items such as car keys, checkbooks, and papers containing important pieces of information. Likewise, children and adults frequently are confronted with requests from others to tell them the whereabouts of missing objects. A daily routine in many households, for example, is getting children to describe where they put their shoes or the last place they remember seeing their homework. Clearly, children's skill in searching for missing objects and describing their whereabouts has important practical consequences. Understanding these skills also has theoretical implications for understanding the development of children's referential communication skills and how spatial information is extracted from the surrounding environment and from memory. Children as young as 4 years are capable of spatially organized searches in situations in which there are relatively few locations that are subdivided into a small number of spatial clusters. For example, Wellman, Somerville, Revelle, Haake, and Sophian (1984) found that 4- and 5-year-olds minimized the number of traverses they made between two clusters of loca

GIS modelling of agricultural soil loss in a plains glacial landscape

Soil erosion on the Canadian Interior Plains is an economic and environmental problem which threatens the sustainability of annual crop production. The conventional approach to regional assessment of erosion risk is the interpretation of soil maps and evaluation of empirical soil loss equations. Use of pre-existing spatial units (quarter-sections, fields, soil map units) simplifies data storage and management, but produces very approximate models of soil landscapes, lacking the spatial resolution of the original maps. Furthermore, a dichotomy exists between the scale of erosional processes and the size of spatial unit in a typical regional study. Parameter values averaged over heterogeneous map units represent a misuse of process models derived from plot-scale experiments. This paper describes the use of a geographic information system (GIS) to model glacial landscapes and evaluate relative erosion risk at a sub-field scale over large areas. When soil and geological surveys, land cover data, and digital elevation models are combined in a GIS, landscapes can be stratified according to the dominant controls on wind and water erosion. This approach ensures geographic integrity and the best soil loss estimates with available data. Maximum use of digital geologic surveys awaits the availability of the three-dimensional GIS.