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.
•Access intensity has time series patterns that create temporal periodic variations.•A workload feedback strategy matches time series variations in access intensity.•A task distribution strategy is devised simply by an association table.•The method achieves efficient load balancing for service resource utilization.
•The WMSP trajectory of micro process of the browsing behavior is defined.•Dimensionality reduction achieves the simplification of the WMSP trajectory.•A novel HGMM model is proposed to model spatial ...structure of the WMSP trajectory.•Using RF to filter fake browsing interest based on the spatial attributes.
Mining the browsing behavior on the web map service platforms (WMSPs) can help to understand the users’ access intentions and provide recommendations. Although WMSPs are popular, the research on browsing behavior is in its infancy. The zoom-in indicates interest increasing whereas the zoom-out indicates interest decreasing. We defined the micro process of the users’ browsing behavior as the trajectory on the WMSP (WMSP trajectory) reflecting the change of interest. Modeling the WMSP trajectory and extracting its maximum browsing interest (BI) are our objectives. WMSP trajectory has multi-dimensional and multi-granular attributes due to the pyramid model of tiles organization making it challenging to achieve that. We constructed a space–time cube to scan the WMSP trajectory and reduce dimensionality. A new hierarchical Gaussian mixture model (HGMM) was proposed to construct minimum trajectory spanning trees via recursive clustering to model the multi-granular spatial structure and extract BIs. The Random Forest model was used to improve the BIs extraction accuracy. We evaluated the effectiveness of the proposed model using real-world data from Tianditu and proved the HGMM is superior to the GMM. This article will help to make WMSPs intelligent.
We present three main research fields in which multimedia cartography and the study of the effectiveness of multimedia maps are currently taking place. In each of these fields, we describe how ...published research is embedded in the broader context of map design and user studies. The research refers to contemporary technological trends such as web HTML5 standards, virtual reality, eye tracking, or 3D printing. Efficiency, performance, and usability studies of multimedia maps were also included. The research published in this issue is interdisciplinary. They combine traditional mapping methods with new technologies. They are searching for new places for cartography in, e.g., the environment of computer games. They combine the design of the map with its perception by users.
This paper summarises the results of an inventory of abandoned underground mines within the Nízký Jeseník Upland (Czechia, Central Europe). The area has a long and complex history of mining. During ...the period between the 11th and 13th centuries, the upland was the centre of ore mining, and later, during the 18th and 19th centuries, it transitioned into slate mining for roofing. From 2016 through 2018, we collected detailed data from 137 mines to better understand their parameters and functioning within the contemporary landscape. The data were mainly focused on the geomorphic character of underground mines, as the existing inventories focus on various other aspects. The results were processed into an interactive web map using ArcGIS Online's online mapping software. Relations between parameters were assessed using three methods: the χ2 test for a contingency table, ANOVA and linear regression.
Sea level rise, a consequence of climate change, is one of the biggest challenges that countries and regions with coastal lowlands will face in the medium term. This study proposes a methodology for ...assessing the vulnerability to sea-level rise on the Atlantic coast of mainland Portugal. Some scenarios of extreme sea levels for different return periods and extreme flooding events were estimated for 2050 and 2100, as proposed by the European Directive 2007/60/EC. A set of physical parameters are considered for the multi-attribute analysis based on the Analytic Hierarchy Process, in order to define a Physical Vulnerability Index fundamental to assess coastal vulnerability. For each sea-level rise scenario, coastal vulnerability maps, with a spatial resolution of 20 m, are produced at a national scale to identify areas more vulnerable to sea-level rise, which are key elements for triggering adaptation plans for such vulnerable regions. For 2050 and 2100, it is estimated that there will be 903 and 1146 km2 of vulnerable areas, respectively; the Lisbon district being identified as the most vulnerable in both scenarios. Results are available as a Web Map Service for the Portuguese public entities, and through a web map viewer for the public and communities in general.
Several factors influence the global-scale cognitive map. The use of school books, atlases and web maps all play an essential role in the development of geographical knowledge of adolescents. This ...research examines the impact of the educational system versus web maps on the adolescents' mental map. Through a specially designed web application, university students and secondary school pupils estimated the real proportion of countries and continents compared to Europe. Participants with a more theoretical background or wider knowledge about map projections and its distortions estimated the real proportions more accurately. This research also found that the Robinson projection, commonly used in schoolbooks and atlases, is the best-known map projection among adolescents. However, the influence of web maps could not be proven since no Mercator effect was found. Education is of undeniable importance, and therefore, educational materials that encourage people to look more carefully and critically at maps should be further developed.
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.
•WMS (Web Map Service) is integrated directly and internally within a BIM authoring tool.•The BIM-WMS integration framework could help with green building certification.•A Revit LEED plugin was developed to showcase the practicability of the framework.
PDF
