Development of a service oriented architecture based geographic information system in earth sciences

Yer bilimlerinde servis odaklı mimari ile coğrafi bilgi sistemi oluşturulması

Abstract

The studies of recent crustal movements are based on analyses of repeated geodetic measurements, and their combination with results of geophysical and geological investigations. It is obvious that a single data producer can not produce useful datasets and information without integrating data from others because one scientist’s results become another’s data. So, the problem to be solved naturally has an interdisciplinary character. However, earth scientists traditionally work on one aspect of the problem and they have a tradition of sharing of data but they are willing to share it if asked. Because of this, the resources are being wasted in duplicative efforts. However, the goal is for data to evolve it into information, and then into knowledge as quickly and effectively as possible. In order to do this, calculations and analysis need to bring to the desktops of researchers, decision-makers, and educators. The aim of this study is to develop a service-oriented architecture (SOA) based Geographic Information System (GIS) that enables linking and sharing multidisciplinary earth science data, tools, and software and to provide a wide range of users access to the system and in this way to build an easy-to-use interactive access to data and analysis environment to study earthquakes in Turkey. In this study, a system was developed to access the earth science data that is available now and data which will be coming online, and to provide users easy access to computation and visualization tools. This study is a motivation for developing the necessary information technology infrastructure applicable to earth science areas. It speeds up the scientific discovery process. It is scalable to accommodate future growth and changes since the framework is based on the service oriented architecture. This architecture allows the modules to be written in separate programming languages, and to be run on different computers over the Internet. GIS is used as a user interface. The functional requirements of the system are the various information technologies. It includes many types of data and algorithms from the field of the earth sciences, computers, GIS, networking and databases. In the study, several software tools are used for processing input data, storing them, and presenting on the web. Most of them are open source programs. Therefore, this study shows the usability of open source software in earth science studies. The study represents a system for calculating strain and analysis of outputs. There are different kinds of methods to obtain strain. Geodetic methods of repeated determination of position are used to obtain and monitor strain accumulation and analysis. The results are affected by the determination of the small regions in which the strain is assumed as homogeneous. In this study, strain from geodetic velocities and also from seismic data is obtained. Seismic hazard assessment depends on the ability to understand where strain in the Earth’s crust is accommodated and how much of this strain is accommodated seismically. So strain rate maps can be used to visualize the present day deformation of Earth’s crust. In the method used, the model grid is continuous in longitudinal and latitudinal directions and covers the study area, Turkey, between 30°N and 45°S and between 20°W and 45°E. The model is calculated on a regular grid. Each grid area is 0.5° x 0.5° in dimension whether an area is considered to be deforming or not is based primarily on seismicity occurrence. This study involves the development of an Internet based system that brings together data, tools, computations and users in a single efficient framework to be used for earthquake related application. A portal based architecture has been adopted in the user interface and service oriented architecture in the middleware. Portals provide users with a single point of access to the system. They also provide a dynamic environment and interactive capabilities. The benefits of this architecture include flexibility and scalability. It also promotes reusability of components. This minimizes the need for new coding. One of the main advantages of Web services is that it does not raise issues of firewalls since it can support any communication protocol. Furthermore, Web services can significantly reduce the data volume and computing resources at the user side. Web services are considered as the next generation of distributed systems because of their advantages such as interoperability.

Özet

Yerkabuğu deformasyonu çalışmaları, tekrarlı jeodezik ölçmelerin analizi ve bunların jeolojik ve jeofizik araştırmalardan elde edilen sonuçlar ile birlikte değerlendirilmesine dayanır. Bir disiplinin ürettiği sonuç, diğer bir disiplinin girdi verisi olduğundan, tek tip veri üreten bir çalışmanın, diğer çalışmalardan üretilmiş değişik tipteki verileri kendi verisi ile entegre etmediği sürece anlamlı bilgi üretemeyeceği açıktır. Bu da göstermektedir ki, çözülmesi gereken problem doğal olarak disiplinlerarası bir karaktere sahiptir. Ancak yer bilimciler genellikle problemin bir yanı üzerine çalışmakta ve sadece istendiğinde verisini paylaşma eğilimindedirler. Bu nedenle kaynaklar, tekrar tekrar aynı çalışmalar üzerinde boşuna harcanmış olmaktadır. Halbuki günümüzde verinin mümkün olduğu kadar çabuk ve efektif olarak bilgiye dönüşmesi gerekmektedir. Bunu gerçekleştirebilmek için hesap ve analiz ortamlarının araştırmacıların, karar vericilerin ve eğitimcilerin masaüstü bilgisayarlarına taşınmış olması gerekmektedir. Bu çalışmanın amacı, çok disiplinli yer bilimleri verilerini, araçlarını ve yazılımlarını birbirine bağlayan ve paylaşımını sağlayan servis odaklı mimari yapıda bir Coğrafi Bilgi Sisteminin oluşturulması ve bu sisteme farklı seviyelerde kullanıcıların (bilimadamı, eğitimci, karar verici vd.) ulaşımının sağlanması ve böylece Türkiye’de depremler ile ilgili çalışma yapmak isteyenlerin, kolay kullanım arayüzü ile interaktif olarak veriye, hesap ve analiz ortamına ulaşmasının sağlanmasıdır. Servis odaklı mimari farklı işletim sistemleri ve platformlarda çalışan ve farklı programlama dilleri ile yaratılmış uygulamalardan elde edilecek dağıtık bilginin belli amaçlar için biraraya gelmesini sağlayan bir çözümdür.