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Three-dimensional coordinate transformations are required to harmonise different types of geospatial data accurately. Developing a mathematical model for data fusion relies on ground control points that produce discrepancies between the physical reality and depicted elements. The disparities between the two coordinate systems are known as the grid-to-ground issue that can be minimised by grid-to-grid or map-to-map transformation. This study develops simplified and rapid models for map-matching with global coordinates using regularised regression approaches to improve the accuracy and reliability of geospatial data. The results indicated that the proposed approach provides superior performance and employs any area with high accuracy. [ABSTRACT FROM AUTHOR]

In human computer interaction, proxemics describes the ways that people use space to interact with other people or objects. We focus on proxemic maps, which are virtual maps in immersive environments that react to proxemic interaction. Proxemic maps take advantage of new opportunities brought about by immersive visualization, where virtual maps can be freely positioned in virtual or physical space and adapt themselves relative to the spatial position of the viewer. We discuss proxemic interactions that alter the content and type of maps, including changing scale, symbolization, type of visualization and geometry. We propose a novel transformation that changes the geometry of maps based on their proximity to users. Users move the map back and forth and the map transitions between ring, horizontal, vertical and cylindrical geometries. The ring geometry surrounds the user and aligns features on the map with features in the real world. We implemented the map transformation in virtual reality and conducted a user study to evaluate it. The results of the user study indicate that participants preferred the ring and horizontal geometries. The ring geometry is useful because it simplifies connecting virtual features on the map with real features in the landscape, while the horizontal geometry provides an overall view of the landscape. We further found that combination of different geometries helped the study participants to overcome the limitations of each geometry. [ABSTRACT FROM AUTHOR]

This paper addresses the problem of feature map merging, which is one of the essential techniques for multi-robot systems. If inter-robot measurements are not available for feature map merging, the only way to obtain the map transformation matrix is feature map matching. However, the conventional feature map matching technique requires too much computation time because it has to be iteratively performed to compute the degree of the mismatch between multiple feature maps. This paper proposes a non-iterative feature map merging technique using virtual supporting lines (VSLs) which is also accurate and robust. The proposed technique extracts the spectral information of multiple feature maps using VSLs and obtains the map transformation matrix using the circular cross-correlation between the extracted spectral information of the multiple feature maps. The proposed technique was tested on feature maps produced by experiments with vision sensors, which was performed non-iteratively. In addition, it consistently showed a high acceptance index, which indicates the degree of accuracy for feature map merging. [ABSTRACT FROM AUTHOR]

The adaptive composite map projection technique changes the projection to minimize distortion for the geographic area shown on a map. This article improves the transition between the Lambert azimuthal projection and the transverse equal-area cylindrical projection that are used by adaptive composite projections for portrait-format maps. Originally, a transverse Albers conic projection was suggested for transforming between these two projections, resulting in graticules that are not symmetric relative to the central meridian. We propose the alternative transverse Wagner transformation between the two projections and provide equations and parameters for the transition. The suggested technique results in a graticule that is symmetric relative to the central meridian, and a map transformation that is visually continuous with changing map scale. [ABSTRACT FROM AUTHOR]

In this work, the effect of hydrostatic initial stress is studied with the exited semiconductor material. Electrons are exited at the free surface of the elastic semiconductor medium using the photo-thermal-elastic theory during the transport (diffusion) process. The thermal memories are due to the dual-phase-lag (DPL) relaxation times of the heat conduction equation with a novel model. In this model, the thermal conductivity is chosen as a linear dependent function of the thermal temperature impact which is variable. The effect of gravitational field is taken into account during the two-dimensional (2D) elastic deformation under the impact of an internal heat source. The Kirchhoff transformation mapping is used. The harmonic wave (normal mode) method is applied for the 2D governing equations to obtain the main physical fields analytically. Some thermal and mechanical forces are applied with other elastic-plasma conditions at the free surface of the semiconductor material to get the complete solutions. Some comparisons used a novel parameters which depend on the DPL model and the differences in the thermal conductivity parameters and they are illustrated graphically and discussed. [ABSTRACT FROM AUTHOR]

This paper addresses the problem of grid map merging for multi-robot systems, which can be resolved by acquiring the map transformation matrix (MTM) among robot maps. Without the initial correspondence or any rendezvous among robots, the only way to acquire the MTM is to find and match the common regions of individual robot maps. This paper proposes a novel map merging technique which is capable of merging individual robot maps by matching the spectral information of robot maps. The proposed technique extracts the spectra of robot maps and enhances the extracted spectra using visual landmarks. Then, the MTM is accurately acquired by finding the maximum cross-correlation among the enhanced spectra. Experimental results in outdoor environments show that the proposed technique was performed successfully. Also, the comparison result shows that the map merging errors were significantly reduced by the proposed technique. [ABSTRACT FROM AUTHOR]

The synthesis of phase functions to manipulate free propagation characteristics of fields is of fundamental concern in wave-optical engineering. In optical and digital holography, two basic approaches have been proposed: the use of diffuse illumination and the application of map transformation techniques. While the first approach uses a scattering concept, the latter applies geometrical optics arguments. In today's optical engineering, both concepts constitute two extreme cases of the general phase synthesis problem which is typically solved by projection algorithms. Characteristics of diffuser-type and mapping-type approaches in phase synthesis are compared with special emphasis on bandwidth, smoothing and information distribution constraints. As a basic tool, iterative Fourier transform algorithms are developed and applied, which do not stagnate in phase vortexes. [ABSTRACT FROM AUTHOR]

Palantir is among the most secretive and understudied surveillance firms globally. The company supplies information technology solutions for data integration and tracking to police and government agencies, humanitarian organizations, and corporations. To illuminate and learn more about Palantir's opaque surveillance practices, we begin by sketching Palantir's company history and contract network, followed by an explanation of key terms associated with Palantir's technology area and a description of the firm's platform ecosystem. We then summarize current scholarship on Palantir's continuing role in policing, intelligence, and security operations. Our primary contribution and analysis are a computational topic modeling of Palantir's surveillance patents (n = 155), including their topics and themes. We end by discussing the concept of infrastructuring to understand Palantir as a surveillance platform, where we theorize information standards like administrative metadata as phenomena for structuring social worlds in and through access to digital information. [ABSTRACT FROM AUTHOR]

Deep learning-based segmentation methods have demonstrated significant performance over their traditional counterparts. However, striving for better accuracy with such networks usually leads to the deterioration of the network's computational efficiency, thereby rendering them inefficient for deployment on resource constraint devices. Establishing the required tradeoff between the accuracy of pixel prediction and computational efficiency remains challenging. In this article, a lightweight multiscale segmentation framework is proposed. We leverage the representation power of different receptive fields to attain optimal accuracy while maintaining computational efficiency by embedding the sparse network architecture with the depthwise separable convolution at the multiscale level. Experimental results from two challenging remote sensing segmentation datasets show that the proposed network can achieve substantial pixel prediction accuracy at relatively low computational overhead compared to state-of-the-art networks. [ABSTRACT FROM AUTHOR]

The novel coronavirus (COVID-19) pandemic is a public health emergency of international concern that caused disaster consequences all over the world. To mitigate and manage the pandemic, geographical information systems (GIS)-based spatial analysis has been used in a key role. To this aim, many GIS-based maps are produced by many national and international institutions. However, the produced maps are prepared by conventional methods and the features in these maps representing by their areal size. This paper proposes the diffusion-based cartograms for visualization of the COVID-19 outbreak. In the study, daily country-level data of the first 150 days of the COVID-19 outbreak were obtained from WHO, and the spread and spatial patterns of the epidemic were presented according to the number of confirmed cases and deaths. As a result of the study, it was observed that the cartogram is a powerful visualization tool and superior to the classical methods. [ABSTRACT FROM AUTHOR]

Future manufacturing systems need to be more flexible, to embrace tougher and constantly changing market demands. They need to make better use of plant data, ideally utilising all data from the entire plant. Low-level data should be refined to real-time information for decision-making, to facilitate competitiveness through informed and timely decisions. The Line Information System Architecture (LISA), is presented in this paper. It is an event-driven architecture featuring loose coupling, a prototype-oriented information model and formalised transformation services. LISA is designed to enable flexible factory integration and data utilisation. The focus of LISA is on integration of devices and services on all levels, simplifying hardware changes and integration of new smart services as well as supporting continuous improvements on information visualisation and control. The architecture has been evaluated on both real industrial data and industrial demonstrators and it is also being installed at a large automotive company. This article is an extended and revised version of the paper presented at the 2015 IFAC Symposium on Information Control in Manufacturing (INCOM 2015). The paper has been restructured in regards to the order and title of the chapters, and additional information about the integration between devices and services aspects have been added. The introduction and the general structure of the paper now better highlight the contributions of the paper and the uniqueness of the framework. [ABSTRACT FROM AUTHOR]

In this investigation, the variable thermal conductivity, which depends on a linear function of temperature, is studied during photothermal excitation processes. The influence of the external magnetic field in the context of volumetrically heat source (optically external source) of an elastic semiconductor medium is investigated. The influence of pulse heat flux and thermal memory of the generalized thermoelasticity theory is taken into consideration. The governing equations are obtained in one dimension (1D) by cylindrical coordinates. The interactions between Photo (carrier density)-elastic and magneto-thermal waves are described analytically. The Laplace transform method in 1D is used to obtain the solutions of principal physical field quantities under investigation. The mechanical deformation during the mechanical loads and thermal gradient temperature are applied on the outer surface of the medium. Fourier series expansion and some numerical techniques are used to get the complete solution of physical fields in the physical time-domain. The resulting physical quantities are obtained numerically, discussed, and graphically presented for an example of a semiconductor material. [ABSTRACT FROM AUTHOR]

Historical maps contain rich geographic information about the past of a region. They are sometimes the only source of information before the availability of digital maps. Despite their valuable content, it is often challenging to access and use the information in historical maps, due to their forms of paper-based maps or scanned images. It is even more time-consuming and labor-intensive to conduct an analysis that requires a synthesis of the information from multiple historical maps. To facilitate the use of the geographic information contained in historical maps, one way is to build a geographic knowledge graph (GKG) from them. This paper proposes a general workflow for completing one important step of building such a GKG, namely aligning the same geographic entities from different maps. We present this workflow and the related methods for implementation, and systematically evaluate their performances using two different datasets of historical maps. The evaluation results show that machine learning and deep learning models for matching place names are sensitive to the thresholds learned from the training data, and a combination of measures based on string similarity, spatial distance, and approximate topological relation achieves the best performance with an average F-score of 0.89. [ABSTRACT FROM AUTHOR]

The amount of data exchanged via the Internet is increasing nowadays. Hence, data security is termed as a serious issue while communication of data is processed over the Internet. Everyone needs their data to be safe during the process of communication. Steganography is the process of hiding a message, audio, image, or video by embedding it into another image, audio, message, or video. It is employed to protect secret data from malicious attacks. This paper presents a categorization of the steganography based on technical and non-technical steganography and also categorized based on its domain. Issues related to steganography are quality of stego images, payload capacity, mean square error, structural similarity (SSIM), Image Fidelity (IF), and Normalized Cross-Correlation (NCC) and robustness. Researchers have already done commendable research in the area of image steganography. Still, it is important to feature the upsides and downsides of the current systems of steganography. The objective of the paper is to examine and scrutinize the different algorithms of steganography based on parameters like PSNR, MSE, and Robustness. Based on the analysis of these parameters and all the issues, this paper concludes with recommendations for producing high-quality stego images, high-payload capacity, and robust techniques of steganography. [ABSTRACT FROM AUTHOR]

Geographic Information Science (GIS) Major in China has been developing and flourishing for nearly 40 years. Chinese educators have made many achievements on major construction in GIS. However, opportunities and challenges coexist under the new situation of 'Double First-Rate' major construction in China. Thus, investigating and analysing the major status comprehensively are necessary for enhancing the development of the GIS major. This study analyses the enrolment magnitude of undergraduate and postgraduate students, student development, construction of teaching team and professional curriculum construction for GIS majors in mainland Chinese universities. The professional survey results showed that there are about 30,000 undergraduates and 4,000 postgraduates who graduate with GIS degrees every year. However, most of the undergraduates in this major do not take gGIS as their first choice in college major selection. In addition, 190 colleges and universities have set up GIS majors, who have played an important role in the development of GIS and industry. These colleges and universities are mostly concentrated in China's central and eastern regions. The Education and Popularization Science Working Committee of the China Association for Geographic Information Society and the Ministry of Education's Education Committee and other institutions have also organized several meaningful activities to strengthen the guidance of the GIS professional construction. A complete education system has been established to train undergraduates and postgraduates for the development of the geographic information industry in China. [ABSTRACT FROM AUTHOR]

Copyright of Annals of the American Association of Geographers is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Geospatial data are now widely available to the general public thanks to geoportals and online mapping platforms. However, creating a map involves more than just combining data layers. Thus we develop cartographic functions for geoportals to support better visual hierarchy in user map mashups. This includes a couple of preparatory steps followed by a smart cartographic background symbolization derived from the original layer style. We evaluate different approaches to background symbolization: greyscale, desaturation, and smart background. The different background symbolization methods are analysed with two concrete map examples and evaluated with a survey. The smart background symbolization developed in this work improves the visual hierarchy of the map mashup by reducing the visual importance of the background layers. [ABSTRACT FROM AUTHOR]

Nowadays, lean implementation seems to be very effective when combined with technologies like radio frequency identification (RFID) but a gap has been observed regarding the availability of certain lean implementation approaches that practice this confluence. Keeping this requirement in view, an extensive systematic literature study has been conducted to first confirm this gap and then to propose an implementation approach by selecting the right approach, methodologies, tools and steps from previous literature. In order to achieve this task, 39 most relevant previous lean implementation approaches have been selected through rigorous search and selection (based on studying their originality, methodology, objectives and limitations) which first confirmed the gap and then enlighten that 56% of previous implementation approaches have utilised 'implementation framework' as the most common approach and the common methodologies utilised were case study and literature review. Moreover, about 25.6% of previous approaches have utilised Value Stream Mapping (VSM) for lean implementation and Technology-Organisation-Environment (TOE) framework was considered as the most appropriate methodology for RFID deployment. So, these statistics were further utilised to invent an implementation framework comprising 21 steps and four implementation phases in which confluence of VSM and TOE has been effectively utilised to achieve successful deployment of technology combined lean. [ABSTRACT FROM AUTHOR]

Trajectory analysis has attracted growing attention in the research field of geography. Beyond traditional moving object trajectories, another type of trajectory exists in which the coordinates are object attributes rather than geographical coordinates. In this paper, a framework to analyse these so-called attribute trajectories is proposed that uses four techniques typically employed in the analysis of moving object trajectories: the Reeb graph, the similarity matrix, the convoy and the mega-convoy. The Reeb graph provides the ability to visualise the temporal dynamics of attribute similarities. The similarity matrix is a supplement of the Reeb graph whose purpose is to visualise the pairwise similarities among the attributes. Moreover, the similarity matrix forms a basis for clustering. The convoy highlights objects whose attributes remain similar for a sufficiently long period. The mega-convoy reduces the number of convoys and reveals their evolutionary histories by merging overlapping convoys. A small real-world meteorological dataset is used as an example to illustrate the attribute trajectory analysis framework and the techniques. This paper aims to form a starting point for applying trajectory analysis techniques in many research fields. [ABSTRACT FROM AUTHOR]

A computer-assisted framework is proposed to support the manual construction of cartograms. The framework employs a joint triangulation, similar to that used in rubber-sheeting, to define a piecewise affine transformation between map space and cartogram space. This guarantees preservation of all topological relations within and among transformed datasets with insertion of a finite number of points. To support intuitive user control of cartogram appearance, methods are developed to translate generically defined user adjustments of the cartogram into mesh vertex positions on either the source map mesh or cartogram mesh. The framework is implemented in a working prototype application and used to create sample cartograms of the USA and China. Results are compared with cartograms produced using diffusion and carto3f algorithms in terms of accuracy, aesthetic appearance, and approximate construction time. Qualitative aspects of the manual construction process are also discussed. [ABSTRACT FROM AUTHOR]

An efficient hyperchaos-based combinational domain encryption scheme for securing iris images during transmission over unsecured data networks or database storage is presented in this article. From the region of interest (ROI) of an iris image, distinctive features are strategically extracted for template creation. The significant part, i.e., the ROI of an iris image, is encrypted in a transformational domain and the nonsignificant region is encrypted in a spatial domain. The advantage of this encryption scheme is increased key space and high degree of security compared to 1-D chaos-based systems. Apart from security, another advantage is reduced computational time compared to conventional encryption schemes implemented in either the spatial or frequency domain. The proposed scheme inherits the advantages of increased key space due to transform orders of the fractional wavelet transform (FrWT) and complex dynamical characteristics of hyperchaos, making the proposed scheme resistant to attacks. The properties of the FrWT and hyperchaos complement each other, making the system efficient and highly robust. Experimental results indicate that the proposed scheme reduces the computational time without compromising the security. Further security analysis is done for various attacks such as differential, statistical, and perceptual attacks, which give promising results and indicate that the proposed encryption scheme is efficient and robust. [ABSTRACT FROM PUBLISHER]

Rural geotourism looks at the natural resources of the territory as a means of promoting a specialized, educational, sustainable tourism. This is an increasingly sought-after activity. This paper presents a rural georoute across a high mountain village, highlighting the remarkable value of the geological heritage of biological trace fossils and physical sedimentary structures exposed on street pavements and façades of houses. A series of tourist georesources were created and implemented: educational and interpretive panels, videos, QR codes, geoapps and games, all of which promote and disseminate the exceptional geological content and the history of the earth through the use of new technologies (smartphones, ipod, etc.). All this is intended as a means to make geotourism a natural tourism, favoring experiences, whilst explaining the natural environment and its temporal and spatial dimensions, offering opportunities for socio-economic development and job creation in rural areas with problems of depopulation. [ABSTRACT FROM AUTHOR]

Enhancers are short regulatory sequences bound by sequence-specific transcription factors and play a major role in the spatiotemporal specificity of gene expression patterns in development and disease. While it is now possible to identify enhancer regions genomewide in both cultured cells and primary tissues using epigenomic approaches, it has been more challenging to develop methods to understand the function of individual enhancers because enhancers are located far from the gene(s) that they regulate. However, it is essential to identify target genes of enhancers not only so that we can understand the role of enhancers in disease but also because this information will assist in the development of future therapeutic options. After reviewing models of enhancer function, we discuss recent methods for identifying target genes of enhancers. First, we describe chromatin structure-based approaches for directly mapping interactions between enhancers and promoters. Second, we describe the use of correlation-based approaches to link enhancer state with the activity of nearby promoters and/or gene expression. Third, we describe how to test the function of specific enhancers experimentally by perturbing enhancer–target relationships using high-throughput reporter assays and genome editing. Finally, we conclude by discussing as yet unanswered questions concerning how enhancers function, how target genes can be identified, and how to distinguish direct from indirect changes in gene expression mediated by individual enhancers. [ABSTRACT FROM PUBLISHER]

Copyright of Regional Studies is the property of Routledge and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The assessment of natural events that can turn into disasters where people live is usually accompanied by maps visualising the specific topic in its spatial setting and putting the physical environment into the main focus. Suchconventionalmapping approaches, however, can often fail to give an intuitive understanding of the underlying quantitative dimension of the associated risk to people and a fuller appreciation of the interrelation between humans and their natural environment. The method presented here demonstrates an alternative way of mapping environmental risk. A gridded cartogram approach is introduced and illustrated with examples drawn from data documenting globally significant earthquakes that have occurred since 2150 BC.Gridded cartogramsare a new map projection. They are created by starting with an equally distributed grid onto which a density-equalising cartogram technique is applied. Each individual grid cell is resized according to specific quantitative information. The underlying grid ensures the preservation of an accurate geographic reference to therealworld. It allows gridded cartograms to be used as basemaps, new projections, onto which other information can be mapped. Earthquake intensity on a gridded population cartogram highlights those zones where most people live in these risk environments and minimises information about where earthquakes still occur, but where they matter less for human populations. Gridded cartograms also allow any other quantitative data to be used in the actual transformation. This is demonstrated with gridded cartograms from earthquake intensity data, resulting in very unusual depictions and new perspectives of the surface of the planet. [ABSTRACT FROM AUTHOR]

This paper examines the spatial patterns of non-work activities for 34 drivers in the Southeast Michigan region. Capitalizing upon a unique global positioning systems (GPS) dataset and GIS visualization techniques, this study quantifies the spatial distributions of non-work activities for drivers with different commuting distances, and for non-work activities that are chained in different types of travel (commute travel vs. non-commute travel). We find a strong dependence of non-work activity locations on commuting distances, and an influence of commuting routes on non-work activities chained in all types of travel. The results underline the importance of commuting routes in shaping the spatial configuration of non-work activities. [ABSTRACT FROM AUTHOR]

In the present study, the multi-temporal satellite images of IRS P6 LISS III were used to map waterlogging dynamics over different seasons. An area of 594.36 km2(6.75%) and 4.17 km2(0.04%) was affected by surface waterlogging during pre and postmonsoon season, respectively. The average annual groundwater level fluctuations were calculated using 18 years (1990–2007) pre and postmonsoon groundwater level data to identify the areas which are under groundwater induced waterlogging conditions. The soil map clearly indicates that salinity and sodicity exhibit the highest severity and occur in areas with shallow groundwater levels. The hydrogeomorphical units mapped using IRS P6 LISS III satellite images are flood plain, alluvial plain, paleochannels, and oxbow lakes. The study revealed that 44.65% areas have very good to excellent groundwater resources. The litholog data clearly indicate an alternating sequence of clay and sand in which deep aquifers made up of coarse sand would be best suited for adequate water supply and good groundwater quality. The integrated study utilizing digital spatial data pertaining to waterlogging, soil salinity, water level fluctuation, and lithological variation proved that planning of any surface and subsurface water resources development activity should be taken up after assessments of said parameters. [ABSTRACT FROM PUBLISHER]

This article presents a fast, free-form rubber-sheet (Carto3F) algorithm for the construction of contiguous area cartograms. Rubber-sheet algorithms are influential and popular because of their conceptual simplicity. Existing rubber-sheet algorithms, however, tend to be algorithmically inefficient and computationally slow. More critically, they cannot completely preserve topology. Carto3F specifically improves rubber-sheet algorithms in these two aspects. First, with a spatial structure of quadtree and a mathematical condition for topological equivalence, Carto3F can prevent topological errors and guarantees topological integrity. Second, Carto3F is designed with efficiency as a priority. Its efficiency is primarily gained through using the auxiliary quadtree to reduce the number of points to be transformed. Furthermore, Carto3F allows parallel computation and can fully take advantage of the increasingly common multi-core, multi-thread processors. Based on the mathematical analysis, Carto3F also mitigates the effect of force cancellation that is inherent in rubber-sheet algorithms. On a computer equipped with a 2.4-GHz quad-core CPU, Carto3F can produce quality population cartograms of the United States, China, and the world within 1 second, 18 seconds, and 8 minutes, respectively. Quantitative measures show that Carto3F outperforms the optimized rubber-sheet algorithm and the diffusion algorithm in both transformation effectiveness and computational efficiency. [ABSTRACT FROM PUBLISHER]

This article relates about some results of an interdisciplinary research project analyzing influencing factors of children's spatial orientation competence in real space carried out by geography educators and psychologists. The focus is on the concept of representation as a theoretical foundation. The research design for collecting data of independent and dependent variables (map-based orientation competence, MBO), and the self-developed measuring instrument are explained. Altogether, 328 pupils of third, fourth, and fifth grade (aged 8–12 years) were tested. The orientation competence of children in strange spaces was slightly above the average, and grew with age. The most spectacular increase was detected on the transition from third to fourth grade. Additionally, boys scored higher than girls. The results also showed that along with age and gender, spatial intelligence (mental rotation) and previous knowledge shape MBO. A limited influence can be attributed to self-concept and previous experiences, while interest has no influence on MBO at all. [ABSTRACT FROM AUTHOR]

Due to rapid technological improvements, it has become easy to acquire remote-sensing images. Therefore, mapping through remote sensing has become convenient and readily available, which saves time and resources. Nevertheless, some key steps need to be performed during the mapping process, including line generalization and smoothing. The former involves retaining the key characteristics of the original map, whereas the latter removes any unnecessary points; both procedures improve the quality of the final map. Many different theoretical and methodological approaches to smoothing and generalization have been proposed by researchers. In this study, we used the Douglas–Peucker method and Topfer and Pillewizer's law to obtain the optimum threshold length. To achieve this threshold, the following were carried out: (1) small-scale line generalization and (2) line generalization by an intermediate map scale transform. From the line generalization and smoothing process, a boundary line map of Little Okinawa Island was subsequently produced. The results of our study may serve as a valuable tool for future remote-sensing mapping tasks. [ABSTRACT FROM AUTHOR]

Historical to recent spatial variability in surface waterlogging was evaluated using a topographical map of 1925 and satellite images of 1975, 1988, 1999 and 2006. A visual satellite image interpretation technique was used to delineate waterlogged areas and associated infrastructure details. Areas of 31, 73.89, 163.86, 143.61 and 102.59 km2 were found to be affected by surface waterlogging during 1925, 1975, 1988, 1999 and 2006, respectively. A sharp increase in waterlogging from 1925 to 1975 is attributed to the functioning of irrigation projects in the region. The very high areas under waterlogging during 1988 and 1999 reflect intensification of agricultural activity. A substantial decrease in waterlogging during 2006 is attributed to the implementation of government wasteland reclamation measures. The area statistics of waterlogging computed for the buffer zone along select features showed that the maximum waterlogging occurs along canals and railways followed by rivers and the least along roads. [ABSTRACT FROM AUTHOR]

This article focuses on the use of map-based multicriteria analysis to develop a negotiation support tool for land use allocation. Spatial multicriteria analysis is used to make explicit trade-offs between objectives and to provide guidance and feedback on the land use changes negotiated by the participants. Digital maps are the means of communication among workshop participants, and an interactive mapping device (the ‘Touch table’) is used as the interface. Participants are informed about the relevant trade-offs on the map and use this information to change the land use maps. The approach is tested during a negotiation session as part of the land use planning process of the Bodegraven polder, a peat meadow area in the Netherlands. [ABSTRACT FROM AUTHOR]

Interpolation procedures are widely used in science, especially in sciences that involve spatial data and continuous phenomena that can be depicted on a continuous spatial surface. Interpolation makes use of accurate and qualitative sampling data in order to produce a continuous representation of the phenomenon in question. The accuracy of the data used for interpolation directly affects the results. This research examines error propagation within the Inverse Distance Weighted (IDW) method, applied as a means of representing the earth's relief. Interpolation of a DEM within contours on a topographical map is considered to be a three-stage procedure. The first stage is the digitising of the contours depicted on the analogue map. Errors involved in this stage are propagated to the second stage, the geometric transformation of coordinates of these digitised contours. Additional errors due to the application of the transformation model are embedded within the results thus obtained. Finally, the errors are propagated to the third stage. Errors are magnified due to the application of an interpolation method, in our case, the IDW method. Any stage of the procedure can be considered separately. The procedure aims to cover the situation where a DEM is created using an analogue topographical map in conjunction with the IDW interpolation method. [ABSTRACT FROM PUBLISHER]