Sensor Data Storage System (SDSS) is a repository in the form of a data base contenting sensor data from monitoring stations and serving for their use and management. Central place in the SDSS data base takes a the concept of Time series which is a sequence of Measurements of one Measurement parameter (for example, temperature or wind speed) in specified Units of measurement at one Station in a three-dimensional point by a Device with a given Serial number. If the measurement conditions change (for example, the measuring device or its location was changed), then one time series is finished and another is began. Often, one physical device identified by its serial number can contain several sensors, measuring or calculating several parameters at the same time (for example, temperature and relative air humidity).Work with SDSS is implemented in a special program accessible through the Web-interface and consisting of several Web-pages, a composition of which depends on the user category. For unregistered users and registered specialists (see Data Access Policy and User Categories) 3 pages: Map, Measurements and Help are available. First two of them allow to display the data in the form of time series plots (section Building time series graphs).
SDSS is a multi-lingual system so it can be used in any language. Any user who speaks in foreign language, if desired, can act as an interpreter, translating all the terms of SDSS to his/her national language on the special page Dictionary.
Most of information in the SDSS is open. But if the data owner for some reason decides to restrict access to them upto some range of users, such an opportunity exists in SDSS. Because of this as well as in relation to the needs of the system itself, all SDSS users are divided into categories. At firstirst of all, they are divided into registered and unregistered users. Latter have the access to all open data and can use them at their discretion, if it does not contradict the rules specified by the data owner in the attached meta information. Registered users can be included to one of following 4 categories:
The users of the category that are below in the list inherit all the rights of the higher category.
Measurement parameter is a property of an object, event, phenomena which is instrumentally observed (for example, wind speed, air temperature).
Device is a sensor device that allows you to register values of the measured parameter. One device can consist of several sensors and so can register several parameters. The device can also be a computer program, the result of which is the calculated values of one of the measured parameters.
Station is a named place with device or device group installed there. In SDSS, area objects can act as stations if their areas are represented as single whole, for example, the level of lake surface.
Time series is a value sequence of one parameter, measured by a physical device during some time at given point ofn 3D space. If the вумшсу producing the measurements is moved in space or replaced by another of the same or different model, the previous series is completed and a new one begins.
Time series block - several time series produced at one point in 3D space by a single physical device. If the device measures / calculates several parameters, then the block contains same time series. The block is characterized by the fact that all its time series have the same measurement time, correspond to the same device and one observation point.
Input data descriptor is a keyword under which the values of the measured parameter arrive to SDSS. The data with the same descriptor and belonging to same data group have the same unit of measurement and refers to one measurement parameter.
Data group is a set of input data with their own descriptors placed in files of same type (with same structure and from one source). Different data groups can contain the data of one measured parameter, but under different descriptors, for example, AirTC in group hymetd and Ta in group meteod.
Specification is a set of technical characteristics of device, defining its peculiarities.
Technical characteristic - description of one of device peculiarity. Each device characteristic is given by its name and value. For example, minimum permissible temperature = -20°C or sensor accuracy = 0.1°С.