Web Processing Service Research Articles

Interoperable web sharing of environmental models using OGC web processing service and Open Modeling Interface (OpenMI)

With the advancement of Web technologies, the service-oriented approach has become increasingly popular to share and couple environmental models. Interoperability is critical to the access and integration of Web services. The OGC Web Processing Service (WPS) defines an interoperable protocol for process execution on the Web. However, it has limitations in supporting time-step calculations that are usually required by complex models, e.g., time marching models. The Open Modeling Interface (OpenMI) standard brings about interoperability for time-step based interactions between modeling components. This paper introduces an approach to sharing environmental models on the Web by coupling OpenMI and WPS. Key issues, including maintaining state, data representation, model description, and model execution, are considered in our approach. An open-source software is developed to support the deployment of the environment models in an interoperable way. TOPMODEL and SWMM5 use cases illustrate the applicability of the approach and implementation.

Web-Based Sea Level Change Simulation System Using PNG Elevation Tiles and Smart Tile Architecture

We have developed a web-based processing system that can simulate positive and negative sea level changes globally by selecting the best Digital Elevation Model (DEM) for a target region from multiple DEMs. A PNG elevation tile format is used as the DEM format, which reduces the DEM data size. The PNG tile format implements client-based processing, and the DEM data are provided from different websites. In addition, the smart tile architecture is adopted, which enables on-demand simulation by adding a tile conversion process (i.e., a DEM selection process) during image drawing by using JavaScript. To demonstrate the system, we have employed three DEMs, i.e., the Geospatial Information Authority of Japan (GSI) map (~10-m resolution), the ASTER Global Digital Elevation Models (ASTER GDEM version 3) as global land area (~30-m resolution), and the General Bathymetric Chart of the Oceans as bathymetric data (~1000-m resolution). The ASTER Global Water Bodies Database is also used in the data selection process. The GSI provides their DEM in a PNG elevation tile format, and the other data are provided by the Geological Survey of Japan in PNG elevation tile format. We assume the current DEM sea level as 0 m, and the sea level can be changed to an arbitrary integer value (−10,000 to 10,000 m). Combining ASTER GDEM for land and GEBCO for sea makes it possible to target DEM of the whole earth. Moreover, it was shown that if a higher resolution DEM is available, it is possible to combine the higher resolution DEM in that area. The combining the PNG elevation tile format with the smart tile architecture demonstrates the possibilities of a client-based web processing service like that of the server-based OGC Web Processing Service.

WPS ENABLED SDI: AN OPEN SOURCE APPROACH TO PROVIDE GEOPROCESSING IN WEB ENVIRONMENT

Abstract. Sharing and management of geospatial data among different communities and users is a challenge which is suitably addressed by Spatial Data Infrastructure (SDI). SDI helps people in the discovery, editing, processing and visualization of spatial data. The user can download the data from SDI and process it using the local resources. However, large volume and heterogeneity of data make this processing difficult at the client end. This problem can be resolved by orchestrating the Web Processing Service (WPS) with SDI. WPS is a service interface through which geoprocessing can be done over the internet. In this paper, a WPS enabled SDI framework with OGC compliant services is conceptualized and developed. It is based on the three tier client server architecture. OGC services are provided through GeoServer. WPS extension of GeoServer is used to perform geospatial data processing and analysis. The developed framework is utilized to create a public health SDI prototype using Open Source Software (OSS). The integration of WPS with SDI demonstrates how the various data analysis operations of WPS can be performed over the web on distributed data sources provided by SDI.

Automatic data matching for geospatial models: a new paradigm for geospatial data and models sharing

ABSTRACTWith the development of global climate and environmental research, geospatial models are becoming more comprehensive and complex and, therefore require more and more input data. In order to improve the efficiency and to save time, labour and money during the preparation of input data, after a discussion of other related studies, this paper describes a new framework that matches existing open web data with geospatial models. The basic idea and general framework are introduced first; four key issues are then studied in detail. The advantages of the new framework are that it can automatically judge whether the open data is the consistent with the input data of the geospatial model according to data similarity values based on unified description factors; if they are not fully consistent, the differences can be intelligently handled using corresponding web processing services and finally, fully matched data can be obtained for use in the geospatial model. Thus, this framework may lead to the development of a new paradigm that links and promotes geospatial data and models sharing. This will not only lead to the greater application of geospatial models, but also greatly amplify the value and usability of open data.

SMODERP2D SOIL EROSION MODEL ENTERING AN OPEN SOURCE ERA WITH GPU-BASED PARALLELIZATION

Abstract. SMODERP2D is a runoff-soil erosion physically-based distributed episodic model used for calculation and prediction processes at agricultural areas and small watersheds. The core of the model is a raster based cell-by-cell mass balance calculation which includes the key hydrological processes, such as effective precipitation, surface runoff and stream network routing. Effective precipitation, the forcing of the runoff and erosion processes, is reduced by surface retention and infiltration. Surface runoff consists of two components: slower sheet and concentrated rapid rill flow. Stream network routing is performed line-by-line in the user predefined polyline layer.SMODERP is a long-term project driven by the Department of Landscape Water Conservation at the Czech Technical University in Prague. At the beginning, SMODERP has been developed as a surface runoff simulated by profile model (1D). Later the model has been redesigned using a spatially distributed method. This version is named SMODERP2D. Ongoing development is focused on obtaining parameters of the hydrological models, incorporating new infiltration and flow routing routines, and conceptualization of a rill flow and rill development. The model belongs to a family of so-called GIS-based hydrological models utilizing capabilities of GIS software for geospatial data processing. Importantly, the SMODERP2D project is currently entering an open source world. Originally the model could be run only in proprietary Esri ArcGIS platform. A new version of the model presented by this manuscript adds support for two key open source GIS platforms, GRASS GIS and QGIS. A newly developed GRASS module and QGIS plugin significantly increases the accessibility of the SMODERP2D model for research purposes and also for engineering practice.Middle scale distributed hydrological models often encounter with high computation costs and long model runtime. Long runtime is caused by high-resolution input data which is easily available nowadays. The project also includes an experimental version of the SMODERP2D model enabling the parallelization of computations. This parallelization is done using TensorFlow, and its goal is to decrease the time needed for its run. It is supported by both CPU and GPU. Parallelization of computations is an important step towards providing SMODERP2D web processing services in order to allow quick and easy integration to highly specialized platforms such as Atlas Ltd.

JupyTEP IDE as an Online Tool for Earth Observation Data Processing

The paper describes a new tool called JupyTEP integrated development environment (IDE), which is an online integrated development environment for earth observation data processing available in the cloud. This work is a result of the project entitled “JupyTEP IDE—Jupyter-based IDE as an interactive and collaborative environment for the development of notebook style EO algorithms on network of exploitation platforms infrastructure” carried out in cooperation with European Space Agency. The main goal of this project was to provide a universal earth observation data processing tool to the community. JupyTEP IDE is an extension of Jupyter software ecosystem with customization of existing components for the needs of earth observation scientists and other professional and non-professional users. The approach is based on configuration, customization, adaptation, and extension of Jupyter, Jupyter Hub, and Docker components on earth observation data cloud infrastructure in the most flexible way; integration with accessible libraries and earth observation data tools (sentinel application platform (SNAP), geospatial data abstraction library (GDAL), etc.); adaptation of existing web processing service (WPS)-oriented earth observation services. The user-oriented product is based on a web-related user interface in the form of extended and modified Jupyter user interface (frontend) with customized layout, earth observation data processing extension, and a set of predefined notebooks, widgets, and tools. The final IDE is addressed to the remote sensing experts and other users who intend to develop Jupyter notebooks with the reuse of embedded tools, common WPS interfaces, and existing notebooks. The paper describes the background of the system, its architecture, and possible use cases.

A provenance metadata model integrating ISO geospatial lineage and the OGC WPS: Conceptual model and implementation

AbstractNowadays, there are still some gaps in the description of provenance metadata. These gaps prevent the capture of comprehensive provenance, useful for reuse and reproducibility. In addition, the lack of automated tools for capturing provenance hinders the broad generation and compilation of provenance information. This work presents a provenance engine (PE) that captures and represents provenance information using a combination of the Web Processing Service (WPS) standard and the ISO 19115 geospatial lineage model. The PE, developed within the MiraMon GIS & RS software, automatically records detailed information about sources and processes. The PE also includes a metadata editor that shows a graphical representation of the provenance and allows users to complement provenance information by adding missing processes or deleting redundant process steps or sources, thus building a consistent geospatial workflow. One use case is presented to demonstrate the usefulness and effectiveness of the PE: the generation of a radiometric pseudo‐invariant areas bench for the Iberian Peninsula. This remote‐sensing use case shows how provenance can be automatically captured, also in a non‐sequential complex flow, and its essential role in the automation and replication tasks in work with very large amounts of geospatial data.

Evaluación automática de la calidad de datos geoespaciales mediante servicios web

The geomatics sector is going through a data overload scenario which new geospatial datasets are generated almost daily. However there are few or nothing infor- mation about the quality of these datasets, and they should be evaluated aiming to provide users some information about their quality. In this context we propose a solution for the automatic quality evaluation of geospatial datasets using the web services platform. This approach is compound by automatic evaluation procedures for quality control of topological consistency, completeness, and positional accuracy described in the Brazilian quality standard. Some procedures require an external dataset for comparison purposes. Hence we provide a set of synthetic datasets and apply over them an experimental design aiming to select suitable methods to find the correspondences between datasets. The solution has an interoperability tier that links users and automatic procedures using the standardized interface of Web Processing Service (WPS). Our results showed that the automatic procedure works very similar to the manual one.

A web service based advanced traveller information system for itinerary planning in an uncertain multimodal network

This article intends to provide an advanced traveller information system based on open geospatial consortium (OGC) standards to perform a fuzzy bi-criteria shortest-path analysis for a multimodal transportation network. To do so, chaining of OGC web services is used to resolve interoperability problems among distributed and heterogeneous resource data. First, a web feature service is assigned to each mode of transportation to gather and convert the data to a standard format, such as geographic markup language. Then, the obtained data are combined to model and construct the multimodal transportation network. Subsequently, a web processing service is designed for performing a fuzzy bi-criteria shortest-path analysis in the multimodal transportation network. Finally, the best routes between the origin–destination pair are presented on a digital map by using a web map service. In the study, among various route-selection criteria, travel time and comfort are considered. To model these criteria, the fuzzy set theory is utilized. By using fuzzy decision tables and a Tsukamoto fuzzy inference system, the desirability of the routes is calculated. The results of comparison among the four travel routes between various origin–destination pairs indicate that the proposed system could be an applicable tool for providing pre-trip information and assisting multimodal travellers under uncertain conditions.

Development of optimal routing service for emergency scenarios using pgRouting and FOSS4G

This study aims to implement a system for Emergency Routing Decision Planning (ERDP) based on Service Oriented Architecture. A Web-based system is implemented to facilitate ubiquitous dynamic routing services on up-to-date road network data. Integration of Dijkstra’s shortest path and Analytic Hierarchy Process (AHP) algorithms has facilitated improved weighted travel-time computation. Route computations are done considering situation at source, transit and destinations. The AHP is used to prioritize amongst possible destinations considering impedance factors affecting travel time. The routing algorithm is deployed as Web Processing Service (WPS) using the ZOO-Project Platform. Two scenarios for application of the ERDP Web services are demonstrated. In the first scenario of medical emergency, the ERDP computes routes between patient’s location, emergency car to hospital in proximity of accident site considering dynamic factors such as conditions of road network, the patient’s state and availability of medical facilities and expertise in the target hospital. In the second scenario of a disaster situation, the GRASS GIS r.sim.water simulation model for overland flow under excess rainfall conditions was integrated into the ERDP system as a WPS. The result of the simulation is used to automatically update the road network database and new routes are computed based on existing conditions. The system is developed using Free and Open Source Software for Geoinformatics (FOSS4G) stack and is amenable to customization to support other emergencies such as fire, debris flow and tsunami. Integration with Sensor Observation Services for automatic data updates from CCTV camera and weather stations could further improve utility as a real-time ERDP system.

Simplifying the deployment of OGC web processing services (WPS) for environmental modelling – Introducing Tethys WPS Server

Developing a complex environmental modelling web application or “web app” can be a challenging task that requires integration of various models and data sources with ever-changing Internet technologies. Service-Oriented Architecture (SOA) has been shown to be useful for building complex modelling workflows. However, compared with other types of web services, such as those for data delivery and mapping, the implementation of Open Geospatial Consortium (OGC) web processing services (WPS) for environmental modelling and data analysis is not very common. This problem stems, in part, from the lack of tools to simplify the development and deployment of WPS for the broad and complex set of environmental modelling applications. This paper presents the development and testing of a ready-to-use WPS implementation called Tethys WPS Server, which provides a formalized way to expose web app functionality as standardized WPS alongside a web app's graphical user interface. The WPS server is created based on Tethys Platform by leveraging PyWPS. Three Tethys web apps are developed to demonstrate how web app functionality(s) can be exposed as WPS using Tethys WPS Server, and to show how these WPS can be coupled to build a complex modelling web app. Moreover, we demonstrate that the services hosted on Tethys WPS Server follow OGC standards correctly and can be used successfully by third party applications and clients that support the OGC WPS specification.

Online image classification and analysis using OGC web processing service

The online geoprocessing and analysis using state-of-the-art technology are offering automated analytical tools to a large group of users. This paper describes an online geoprocessing and analysis framework, which allows an inexperienced user to perform unsupervised classification of remote sensing data. The parallel computing based geoprocessing and analysis framework adopted in this work has been implemented using Free and Open Source Software for Geospatial (FOSS4G). Web Processing Service (WPS) based geoprocessing framework facilitates the deployment of unsupervised classification algorithm on the web in a standardized way. However, it is dynamic in nature to deploy other geoprocessing algorithms. The developed system describes how to process remote sensing data (Sentinel-2, Landsat-8, etc.) for classification and sharing the interoperable results in a distributed environment. To validate the classification results, a prototype architecture based on participatory GIS is developed for field data collection, accuracy assessment and online dissemination. The accuracy assessment (i.e., overall accuracy, Kappa coefficient) is performed to validate the derived classification results using collected field data.

OGER++: hybrid multi-type entity recognition

BackgroundWe present a text-mining tool for recognizing biomedical entities in scientific literature. OGER++ is a hybrid system for named entity recognition and concept recognition (linking), which combines a dictionary-based annotator with a corpus-based disambiguation component. The annotator uses an efficient look-up strategy combined with a normalization method for matching spelling variants. The disambiguation classifier is implemented as a feed-forward neural network which acts as a postfilter to the previous step.ResultsWe evaluated the system in terms of processing speed and annotation quality. In the speed benchmarks, the OGER++ web service processes 9.7 abstracts or 0.9 full-text documents per second. On the CRAFT corpus, we achieved 71.4% and 56.7% F1 for named entity recognition and concept recognition, respectively.ConclusionsCombining knowledge-based and data-driven components allows creating a system with competitive performance in biomedical text mining.

Mobile Application and a Web-Based Geographic Information System for Sharing Geological Hazards Information in East and Southeast Asia

This paper presents a mobile application and a web-based geographic information system for an efficient and cost-effective sharing of geological hazards information in East and Southeast Asia. The information system uses the Open Geospatial Consortium (OGC), Web Map Service (WMS) and Web Processing Service (WPS) for spatial data rendition and processing online. Free and Open Source Software (FOSS) is also used for other important spatial data processing and sharing operations. WMS and WPS are formulated to access and view the geological hazard data in the system’s database. The mobile application is developed to access and share the system’s geospatial contents by sending requests to these web services. The application also makes geological hazard mitigation measures more effective by incorporating the mobile device’s GPS location information with geological hazard data. Information like the distance from the nearest active fault, active volcano and earthquake hypocenter can be easily determined using the application. The mobile application provides an interface for the users to easily access geological hazard information such as active fault, active volcanoes, shorelines inundated by tsunamis, and historical and real time seismic events. The widespread use of mobile devices with Internet connection makes geological hazard information dissemination very efficient using the application. The mobile application is called G-EVER Mobile. G-EVER stands for Asia Pacific Region Global Earthquake and Volcanic Eruption Risk Management consortium. The application can be accessed at https://ccop-geoinfo.org/gever-mo/index.php.

Geoinformation Sharing System for East and Southeast Asia Using SDI, OGC Web Services and FOSS

This paper presents an innovative, cost-effective and efficient web-based sharing system for geoscience information among the countries in East and Southeast Asia. The information system’s main components are organized following the Spatial Data Infrastructure (SDI) model. It also uses the Open Geospatial Consortium (OGC) Web Map Service (WMS) and Web Processing Service (WPS) for online spatial data rendition and processing, respectively. Free and Open Source Software (FOSS) are also used for other important spatial data processing functions. The geospatial contents of the information system are stored and managed using the open source software PostgreSQL and its PostGIS extension. The information system makes spatial data sharing more efficient and organized by formulating a hierarchical information content classification scheme and the option for the users to put up their own customized WebGIS portals. These give users the option to show their chosen geospatial contents on their own web-based platform. The information system also makes spatial data sharing more flexible by providing data owners the choice to determine the data access privileges for each user or group of users. It also provides module for processing, rendering and sharing Japan’s ASTER satellite images. The information system is called GSi for Geoinformation Sharing Infrastructure for East and Southeast Asia. The URL of the web-based information system is https://ccop-gsi.org/main/index.html.

The dynamic reconfiguration approach for fault-tolerance web service composition based on multi-level VCSOP

The dynamism of web service on the internet brings new needs to build autonomous services. In practical environments, Web services could occur many incidents with unacceptable information and generate a large number of undesirable solutions. Thus, it becomes an additionally urgent challenge on how to adjust service-based applications to meet highly dynamic environments and fast-changing business requirements. A self-reconfigurable application becomes a necessity to produce an adequate web service process. To cope with this hindrance, the present paper proposes a sensor and repair-based algorithm to achieve reliability at the component level before a system crash occurs. We adopt a new sensor method based on project management rules to detect the faulty region on a workflow. After that, we applied the repair algorithm: such as a single service (SSR) and multiple service reconfiguration (MSR) that systematically search to find a new nearby solution. In MSR algorithm we referred to a new multi-level VCSOP with Harmony Search (HS) metaheuristic to quickly recover the faulty region without system crash. The results show that our proposed method could recover the original instance of the faulty region without user integration and in a very acceptable time regarding the recomposing process.

Exploring cloud-based Web Processing Service: A case study on the implementation of CMAQ as a Service

As an important tool for air quality simulation, the Community Multiscale Air Quality (CMAQ) model is widely used in the environmental modeling community. However, setting up and running the CMAQ model could be challenging for many scientists, especially when they have limited computing resources and little experience in handling large-scale input data. In this study, we explore the cloud-based Web Processing Service (WPS) and present the Cloud WPS framework to support implementing Earth science model as WPS. Specifically, to make CMAQ easier to use for scientists through the latest standard-based Web service technology, CMAQ-WS, a prototype of CMAQ as a Service, is developed and tested. The result of the experiment shows the framework significantly improves not only the performance of but also ease of use of the CMAQ model thus providing great benefits to the environmental modeling community. Meanwhile, the proposed framework provides a general solution to integrate Earth science model, WPS, and cloud infrastructure, which can greatly reduce the workload of Earth scientists.

EXPOSING AND PROVIDING ACCESS TO INDIAN BIORESOURCE INFORMATION NETWORK (IBIN) SPECIES OCCURRENCE DATASET AS WEB SERVICE USING OGC WPS STANDARD

Abstract. Species occurrence data are collected by many researchers worldwide as record of species present at a specific time at some defined place as part of biological field investigation serving as primary or secondary dataset. These datasets reside in separate silos across numerous distributed systems having different formats limiting its usage to full potential. IBIN portal provides a single window for accessing myriad spatial/non-spatial data on bioresources of the country. To promote reuse of occurrence dataset among organizations in an interoperable format including support for integration across various platforms & programming languages, it is been exposed as web service using OGC Web Processing Service (WPS) standard. WPS provides standardized interface for performing online geo-processing by exposing spatial processes, algorithms and calculations thereby enabling machine to machine communication and wider usage in various scenarios (e.g. service chaining etc.). Open source ZOO-project is used for developing the ‘Species Search’ WPS service. WPS takes inputs as either the species name or bounding box or shapefile defining the area of interest and returns queryable OGC complaint Web Map Service (WMS) as output with specie(s) occurrences represented in grid (5km x 5km) format, with each grid possessing attributes like specie(s) name, family, state, medicinal detail etc. WPS process can be invoked asynchronously, enabling proper feedback regarding status of the job submitted. JavaScript based web client for consuming this service has also been developed along with custom QGIS plugin to allow potential users to access the same in GIS software for wider reusability.

Full Meta Object profiling for flexible geoprocessing workflows

AbstractThe design and running of complex geoprocessing workflows is an increasingly common geospatial modelling and analysis task. The Business Process Model and Notation (BPMN) standard, which provides a graphical representation of a workflow, allows stakeholders to discuss the scientific conceptual approach behind this modelling while also defining a machine‐readable encoding in XML. Previous research has enabled the orchestration of Open Geospatial Consortium Web Processing Services (WPS) with a BPMN workflow engine. However, the need for direct access to predefined data inputs and outputs results in a lack of flexibility during composition of the workflow and of efficiency during execution. This article develops metadata profiling approaches, described as two possible configurations, which enable workflow management at the meta‐level through a coupling with a metadata catalogue. Specifically, a WPS profile and a BPMN profile are developed and tested using open‐source components to achieve this coupling. A case study in the context of an event mapping task applied within a big data framework and based on analysis of the Global Database of Event Language and Tone database illustrates the two different architectures.

A Performance Evaluation of a Geo-Spatial Image Processing Service Based on Open Source PaaS Cloud Computing Using Cloud Foundry on OpenStack

Recently, web application services based on cloud computing technologies are being offered. In the web-based application field of geo-spatial data management or processing, data processing services are produced or operated using various information communication technologies. Platform-as-a-Service (PaaS) is a type of cloud computing service model that provides a platform that allows service providers to implement, execute, and manage applications without the complexity of establishing and maintaining the lower-level infrastructure components, typically related to application development and launching. There are advantages, in terms of cost-effectiveness and service development expansion, of applying non-proprietary PaaS cloud computing. Nevertheless, there have not been many studies on the use of PaaS technologies to build geo-spatial application services. This study was based on open source PaaS technologies used in a geo-spatial image processing service, and it aimed to evaluate the performance of that service in relation to the Web Processing Service (WPS) 2.0 specification, based on the Open Geospatial Consortium (OGC) after a test application deployment using the configured service supported by a cloud environment. Using these components, the performance of an edge extraction algorithm on the test system in three cases, of 300, 500, and 700 threads, was assessed through a comparison test with another test system, in the same three cases, using Infrastructure-as-a-Service (IaaS) without Load Balancer-as-a-Service (LBaaS). According to the experiment results, in all the test cases of WPS execution considered in this study, the PaaS-based geo-spatial service had a greater performance and lower error rates than the IaaS-based cloud without LBaaS.