Master's thesis analyses and highlights the most important characteristics of the optimal real time environmental measuring system. Technical implementation of distributed measuring system DEMS (Distributed Environmental Measuring System) with X-DEG (Distributed Environmental Gateway), as a basic gateway is shown. System is primarily built for continuous environmental monitoring and providing and delivering high-quality environmental data in real time.
The introduction presents the role of the Slovenian Environment Agency (SEA), as the institution responsible for providing and delivering high-quality environmental data in real time. Also objectives and guidelines as well as requirements that were followed in designing and developing the optimal measuring system DEMS and the X-DEG platform are presented.
Separate segments of SEA measuring network (meteorological, hydrological and air quality) with basic features and implemented measuring quantities are shortly introduced.
The following chapter presents the implemented DEMS network with integrated supportive virtual servers for managing distributed X-DEG measuring systems and traceable software, hardware and documentation management (Redmine, SVN - Software Versioning And Revision Control System, Wiki, Visualization server).
Fourth chapter presents the design of the X-DEG high performance communication platform with distributed modular concept of hardware and software. Functionality is based on embedded Linux operating system where, from the user point of view, sensor kernels, called sensord modules are running independently. Each sensord can be associated with physical UART or TCP/IP communication channel. It manages the connected sensors and performs data acquisition. Sensord as measuring system constitutive element ensures design of hierarchic tree and node modular structure.
Job manager daemon called JMD module is used as gateway for coordination and data dissemination, supervising sensord performance. It also assures data archiving and periodical data transmission to remote data center. The characteristics of the optimal measuring system that are strongly related with built in software services and functionalities that are implemented at the level of X-DEG communication platform are described.
In the goal to achieve remote measuring networks and data management the platform should be designed with appropriate interfaces and supported by appropriate services.
Furthermore, the implementation of standard user telnet command line interpreter TCLI is described. The xml configuration of the application software (sensord and JMD modules) as a basis of structure hierarchy and functional operation of measuring system is presented.
The implementation of environmental measuring system at the level of sensors and instruments connectivity and integration into measuring network is shown.
The data flow specification at the level of sensord module is presented in chapter 5. Some algorithms for basic continuous meteorological quantities, such as temperature or relative humidity, and example of interval data processing for precipitation are shown.
Conclusion gives the results achieved with the implementation of DEMS and X-DEG as a high-performance measuring system, from the aspect of set objectives and requirements.
X-DEG measuring systems are field-tested and operational functioning at 285 locations of hydrological and meteorological national measuring network. The system was also tested and installed at some air quality measuring sites. Production of installed measuring systems DEMS / X-DEG was performed in SEA laboratory.