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Load-balancing strategies address challenges stemming from intensive access and heavy communication traffic on a Web map service platform (WMSP) by collecting workload-related information from cluster-based servers, and distributing tasks to minimize the consumption of computational and caching resources. However, intensive user access has time series patterns that create temporal periodic variations that can be exploited to improve the performance of the WMSP. In this paper, we propose a variable feedback strategy based on time series variations in the intensity of user access to increase the efficiency and reliability of workload feedback with little resource consumption. A task distribution strategy, based on the expected values of the arrival rate that match real-time conditions in workload feedback periods and the real-time processing capability of each cluster-based server, is devised simply and accurately by an association strategy for workload and service rate that supports services insensitive to massive numbers of concurrent access requests. The results of experiments show that the proposed strategy provides quick responses and high throughput for large-scale user access. It implements efficient load balancing for service resource utilization, and can thus improve the stability and capacity of the WMSP server using heterogeneous back-end cloud cluster-based servers.

Selection of construction material sources is an important issue in construction supply chain management. This affects not only the shipping cost and schedule of a construction project, but also its environmental impact. However, material delivery cost and time from the source location to the job site concerning sustainability may not be easily estimated. In this paper, a decision support tool that integrates building information modeling (BIM) and web map service (WMS) for the source selection of sustainable construction materials is presented. The BIM-WMS integrated decision support tool is developed in a form of a BIM-integrated plugin, which can help select sustainable construction material sources through evaluating the final cost and delivery time of the material, as well as calculate location-related credits in some green building standards, such as LEED. The developed plugin will make the selection of sustainable construction material and the calculation of location-related credits in green building certification an easy task, with the goal of minimizing environmental impact.

We present the design, development, and testing of a new software package for generating snow cover maps. Using a custom inverse distance weighting method, we combine volunteer snow reports, cross-country ski track reports and station measurements to fill cloud gaps in the Moderate Resolution Imaging Spectroradiometer (MODIS) snow cover product. The method is demonstrated by producing a continuous daily time step snow probability map dataset for the Czech Republic region. For validation, we checked the ability of our method to reconstruct MODIS snow cover under cloud by simulating cloud cover datasets and comparing estimated snow cover to actual MODIS snow cover. The percent correctly classified indicator showed accuracy between 80 and 90% using this method. The software is available as an R package. The output data sets are published on the HydroShare website for download and through a web map service for re-use in third-party applications.

In green buildings design and construction, evaluating the sustainable effects of site location and transportation to the ecosystem and human life is a critical and difficult task. Works regarding these matters require experience, time, labor, and manual calculations. In recent years, many studies have been conducted to enhance the application of Building Information Modeling (BIM) in green building certifications. However, the application of BIM to site location and transportation analysis is usually considered impractical due to the lack of a powerful map application in present BIM products. The aim of this research is to develop a framework for the integration of BIM and Web Map Service (WMS) technologies for location and transportation analysis in green building certifications. Using Autodesk Revit API and Google Maps API as the development tools, this research converts the integration model into the BIM-integrated plugin in Autodesk Revit. The plugin is used to streamline the certification process of site location and transportation analysis in LEED (Leadership in Energy and Environmental Design), one of the most popular and globally recognized green building standards.

Problem: The power & electric outages cause business disruptions that result in economic impacts to cities. A web map service (WMS), as a RESTful API with URL, that makes real-time information of power outage and economic loss estimation accessible and available across the web would be valuable and important for decision makers in smart cities and smart energy utility. Objective: This paper presents a web-based system that is capable of creating real-time WMS. Our system enables geo-enabled applications (such as web mapping, mobile GIS app, operations dashboard) to access, query, and display a web map of real-time outage status and economic loss information associated with outages in the county scale. Method: Our method is based on the Internet of Things (IoT), web services, GIS web services, web mapping, and web GIS (Geographic Information Systems). To implement our system, we used esri ArcGIS for Server, SQL Server Spatial, Amazon Web Services, and C#.NET. The system architecture consists of autonomous computer program, spatial database, GIS Server, cloud computing platform, a WMS, web feature service (WFS). Our insight is in real-time by continuously 1) connecting to web sensors and collecting outage data, 2) connecting to web services for calculating economics loss associated with outages, 4) manipulating (modify, insert, delete) our spatial database over the Internet, 4) publishing a real-time WMS. Result: The system implementation resulted in a back-end server that includes /serves a real-time WMS. A data record includes: name of county, name of state that contains this county, total number of costumers located within the county, total number of costumers without electricity who are located into the county, and total economic losses (modeled as total jobs loss, total GDP loss, and total cost in $) caused by outages for the county. Findings: Real-time WMS created by our system can be used by applications to display and query a web map of electric outage status and their macroeconomic loss in real-time. They provide a decision support tool for disaster emergency management in the energy sector by aiding in prioritization of restoration operations and recovery phase in electric utilities in order to reduce the economic impact of outages. Our system provides an important platform for smart cities, real-time GIS, Internet on Things, map-based crowdsourcing applications, real-time intelligent systems, and for real-time monitoring and analytical applications.

We describe ncWMS, an implementation of the Open Geospatial Consortium’s Web Map Service \ud (WMS) specification for multidimensional gridded environmental data. ncWMS can read data in a \ud large number of common scientific data formats – notably the NetCDF format with the Climate and \ud Forecast conventions – then efficiently generate map imagery in thousands of different coordinate \ud reference systems. It is designed to require minimal configuration from the system administrator \ud and, when used in conjunction with a suitable client tool, provides end users with an interactive \ud means for visualizing data without the need to download large files or interpret complex metadata. \ud It is also used as a “bridging” tool providing interoperability between the environmental science \ud community and users of geographic information systems. ncWMS implements a number of \ud extensions to the WMS standard in order to fulfil some common scientific requirements, including \ud the ability to generate plots representing timeseries and vertical sections. We discuss these \ud extensions and their impact upon present and future interoperability. We discuss the conceptual \ud mapping between the WMS data model and the data models used by gridded data formats, \ud highlighting areas in which the mapping is incomplete or ambiguous. We discuss the architecture of \ud the system and particular technical innovations of note, including the algorithms used for fast data \ud reading and image generation. ncWMS has been widely adopted within the environmental data \ud community and we discuss some of the ways in which the software is integrated within data \ud infrastructures and portals.

The effectiveness of decision-making processes in the agricultural domain can be improved by integrating current local environmental and agromonitoring with the Geographic Information System (GIS) and wireless sensor networks (WSNs). The presented paper describes conceptual approaches to context-based cartographic visualization methods for agricultural and metrological data acquired by WSN and a portal prototype for integrated visualization. Each sensor used for agricultural applications has a location and can be placed within a broader spatial context. In our study, sensor characteristics (soil temperature and moisture, atmospheric temperature and moisture) were automatically monitored at frequent intervals and these readings were aggregated with geospatial data from both local and remote (Web Map Service) sources. An experimental portal for the integration and visualization of sensor data and geospatial data was designed and prototyped on the basis of an open source interoperable platform. Conceptual approaches were successfully implemented on four experimental small-plot fields planted with different crop species and operated using different soil tillage practices. Experimental fields were situated in the southeast of the Czech Republic. Very Long range Identification Tag (VLIT) technology was used for wireless communication. Sensor observations verified differences in agrometeorological variables for the conventional tillage of soil and the no-tillage variant. Contextual cartographic visualization was successfully deployed for map view, dynamic cartographic symbology, and the dynamic measurement chart.

Web mapping has become a popular way of distributing interactive digital maps over the internet. Instead of dynamically generating map images on the fly, those can be pre-generated and served from a server-side cache for faster retrieval. However, these caches can grow unmanageably in size when the cartography covers mid to large areas for multiple rendering scales. This forces modest organizations to use partial caches containing just a subset of the total tiles, and makes their services less attractive than other mapping services like Google Maps or Microsoft Bing Maps. This work proposes a neural-network-based intelligent system that predicts which areas are likely to be requested in the future from a catalog of geographic features and a short history of past requests. These priority regions can be used by a tile prefetching policy to achieve an optimal population of the cache. Neural networks are trained and validated using supervised learning with real data-sets from a public nation-wide web map service. Trace-driven simulations demonstrate that accurate long-term predictions, up to 90% in terms of cache-hit ratio, can be obtained with the proposed model by prefetching a low fraction, only the 20% of the total tiles, and with a short training period.

By applying advanced Geospatial Data Abstraction Library (GDAL) and BigTIFF technology in a Geographical Information System (GIS) with Service Oriented Architecture (SOA), this study has derived global datasets using tile-based input data and implemented Virtual Web Map Service (VWMS) and Virtual Web Coverage Service (VWCS) to provide software tools for visualization and acquisition of global data. Taking MODIS Normalized Difference Vegetation Index (NDVI) as an example, this study proves the feasibility, efficiency and features of the proposed approach.

Combining emission inventory methods and geographic information systems (GIS) remains a key issue for environmental modelling and management purposes. This paper examines the development of a web GIS application as part of an emission inventory system that produces maps and files with spatial allocated emissions in a grid format. The study is not confined in the maps produced but also presents the features and capabilities of a web application that can be used by every user even without any prior knowledge of the GIS field. The development of the application was based on open source software tools such as MapServer for the GIS functions, PostgreSQL and PostGIS for the data management and HTML, PHP and JavaScript as programming languages. In addition, background processes are used in an innovative manner to handle the time consuming and computational costly procedures of the application. Furthermore, a web map service was created to provide maps to other clients such as the Google Maps API v3 that is used as part of the user interface. The output of the application includes maps in vector and raster format, maps with temporal resolution on daily and hourly basis, grid files that can be used by air quality management systems and grid files consistent with the European Monitoring and Evaluation Programme Grid. Although the system was developed and validated for the Republic of Cyprus covering a remarkable wide range of pollutant and emissions sources, it can be easily customized for use in other countries or smaller areas, as long as geospatial and activity data are available.

Orthoimages are essential in many Web applications to facilitate the background context that helps to understand other georeferenced information. Catalogues and service registries of Spatial Data Infrastructures do not necessarily register all the services providing access to imagery data on the Web, and it is not easy to automatically identify whether the data offered by a Web service are directly imagery data or not. This work presents a method for an automatic detection of the orthoimage layers offered by Web Map Services. The method combines two types of heuristics. The first one consists in analysing the text in the capabilities document. The second type is content-based heuristics, which analyse the content offered by the Web Map Service layers. These heuristics gather and analyse the colour features of a sample collection of image fragments that represent the offered content. An experiment has been performed over a set of Web Map Service layers, which have been fetched from a repository of capabilities documents gathered from the Web. This has proven the efficiency of the method (precision of 87% and recall of 60%). This functionality has been offered as a Web Processing Service, and it has been integrated within the Virtual Spain project to provide a catalogue of orthoimages and build realistic 3D views.

Ensuring interoperability between WebGIS applications is essential for maximizing access to data, data sharing, and data manipulation. Interoperability is maximized through the adoption of best practices, use of open standards, and utilization of spatial data infrastructure (SDI). While many of the interoperability challenges like infrastructure, data exchange, and file formats are common between applications, some regions like the Arctic present specific challenges including the need for presenting data in one or more polar projections. This paper describes the Arctic Research Mapping Application (ARMAP) suite of online interactive maps, web services, and virtual globes (the ARMAP suite; http://armap.org/) and several of the interoperability challenges and solutions encountered in development to date. ARMAP is a unique science and logistic tool supporting United States and international Arctic science by providing users with the ability to access, query, and browse information and data. Access to data services include a text-based search utility, an Internet Map Server client (ArcIMS), a lightweight Flex client, ArcGIS Explorer and Google Earth virtual globes, and Open Geospatial Consortium (OGC) compliant web services, such as Web Map Service (WMS) and Web Feature Service (WFS). Through the ARMAP suite, users can view a variety of Arctic map layers and explore pertinent information about United States Arctic research efforts. The Arctic Research Logistics Support Service (ARLSS) database is the informational underpinning of ARMAP. Avoiding duplication of effort has been a key priority in the development of the ARMAP applications. The ARMAP suite incorporates best practices that facilitate interoperability such as Federal Geographic Data Committee (FGDC) metadata standards, web services for embedding external data and serving framework layers, and open standards such as Open Geospatial Consortium (OGC) compliant web services. Many of the features and capabilities of ARMAP are expected to greatly enhance the development of an Arctic SDI.

Over the past 10 years, there have been great advances in the interoperability technologies in geographic information science. More than 10,000 map layers are available online today through Open Geospatial Consortium (OGC) specified interfaces, such as Web Map Service (WMS), Web Feature Service (WFS), and Web Coverage Service (WCS). These map layers are persistently serving the geospatial communities; however, our empirical study found that their potential value has not been fully exploited. Frequently, a targeted map cannot be composed because some published map servers are unavailable. This problem becomes more serious when a map is composed of several layers from different servers. These services are geographically distributed and maintained by various hosts; therefore, simply waiting for service improvement on the host side cannot solve this problem. In this paper, we proposed a new approach and developed a mechanism that allows clients to select the best map layers at run-time. The selection is based on the results of continuous monitoring and evaluation of the quality of WMSs. Based on Service Oriented Architecture (SOA), this approach includes quality monitoring and evaluation modules. Quality factors are taken into account during the process of registration, search, and bind. The OGC capability document is extended to include WMS quality information. Three prototype systems were developed in this study to demonstrate: (a) how WMS layers are monitored and evaluated, (b) how the subjective evaluation of WMS quality by a user is collected, and (c) how this can be a feasible method to fuse WMS resources suitable for decision making.

Surveillance and exchange of gathered information guides emergency response as well as long-term planning. In this paper we have discussed about the Open GIS, which can be very well utilized during different health hazards and in response to that some immediate actions can be taken up based on the available latest information in the said system. Open Source Web GIS software systems have reached a stage of maturity, sophistication, robustness and stability, and usability and user friendliness rivaling that of commercial, proprietary GIS and Web GIS server products. The Open Source Web GIS community is also actively embracing OGC (Open Geospatial Consortium) standards, including WMS (Web Map Service). WMS enables the creation of Web maps that have layers coming from multiple different remote servers/sources. Here we present one easy to implement .Web GIS server solution that is based on the Open Source Map Server. With the help of step-by-step instructions, interested readers running mainstream machines and with no prior technical experience in Web GIS or Internet map servers will be able to publish their own health maps on the Web and add to those maps additional layers retrieved from Remote WMS servers. All problems with planning and management are related to location, they are geographically referenced and require spatial analysis and presentation, an Open GIS on any compatible GIS platform will be very helpful tool for planning and decision making in emergency management. The geographical information system (GIS) is a tool used generically for any computer based capability for manipulating geographical data. The hardware and software functions of GIS include data input, data storage, data management (data manipulation, updating, changing, exchange) and data reporting (retrieval, presentation, analysis, combination, etc.).All of these actions and operations are applied to GIS as a tool that forms its database. The paper describes the types of the GIS data formats (vector, raster), database object definitions, relationships, geometric features, and the data organization structure. Some GIS applications and examples are given for better understanding of how GIS data can be used in GIS applications, with the respect to data formats, including surface elevation and slope from Digital Elevation Model data (DEM), with the applicability in water industry.