Information-measuring complex and database of mid-latitude...

Internet Technologies in Borok Geophysical Observatory

[68] There is most operatively and conveniently for users to access the data via Internet. If users deal with any database parts, distributed on any media, then they can use access and processing programs, designed for the Internet too. Thus, the interface is unified, allowing the user to get data from the database web server via Internet as well as from the database media on the personal computer without Internet access. The free-of-charge software with open sources is used to provide the Internet access and to design the database processing programs. So, the data processing programs of Borok Geophysical Observatory database are written in Pascal and C programming languages supported by Linux. Programs of data requests processing are written in Perl 4 language using the CGI interface. All database software was developed and distributed under the GNU General Public License.

[69] The free access data of the Borok Geophysical Observatory database are located in the data directories of the database server. They include the data on geomagnetic field variations, ULF geomagnetic pulsations, atmospheric electric field vertical component and meteorological data.

Figure 7

[70] The visual information on all geophysical fields, accessible via Internet, is located in corresponding subdirectories (Magnet, Geopuls, Electric and Weather) as the gif files, produced by the data processing software. The separate files contain the common information on the presented data (files index.html), the description of the measuring complex and sensors (sensors.html), database manuals (help.html), and also data request forms (request.html). The visual information files (pictograms, trade marks, plots and spectral-temporal diagrams) are stored in the subdirectories img. The scheme of the database web server is presented on Figure 7. All text information has HTML format, the visual information is presented in gif and jpeg formats. The database home page (http://geobrk.adm.yar.ru:1352/index.html) references to web sites of the organizations supporting the database. There are links to web sites of Russian Academy of Sciences (http://www.ras.ru), the Russian Foundation for Basic Research (http://www.rfbr.ru), the Schmidt Institute of Physics of the Earth (http://www.ifz.ru), Borok Geophysical Observatory (http://wwwbrk.adm.yar.ru) and Geoelectromagnetic Monitoring Laboratory (http://wwwbrk.adm.yar.ru/gemm/index_e.html).

Figure 8

[71] From the home page the web-site visitor can go to database manuals, to rules of the road and to the geophysical data pages, presented the results of measurements of geomagnetic variations, ULF geomagnetic pulsations, atmosphere electric field and meteorological parameters. The home page and page with site map are presented on Figure 8.

[72] All web-site pages have in the left side the menu with links to current level sub-items and logo of Borok Geophysical Observatory, linking to web-site home page.

[73] The menu items referencing to the data viewing (View Data) specify not html files, but the program to generate html-file to view the data. On the first call (without parameters) the program generates the html-file which displays the selected geophysical parameter of the last day or month. Thus the graphic files generated by the data processing programs are used. On next calls from earlier generated files the program gets as parameter the date of the data set to visualize. The program creates the html files displaying the selected geophysical parameter for the selected date. Thus generation of html-pages to view the data is invisible for the user, who goes from one date to another, using the references at the generated html-pages.

Figure 9

[74] To provide data safety and to prevent hacker attacks the raw data files are locked. The data, requested by database users, are formed by the database web-site software. The user requests the data by filling the data request form, special for each data type; however the algorithm to processing of the data request form is identical to all data types. Data display page and an example of the data request form for the geomagnetic field variations are presented on Figure 9. The user has to fulfill the form fields Time Interval (pointing year, month, day and hour), First Name (pointing user's name), Surname (pointing user's family name), E-mail (the e-mail address). After processing of the data request the user receives via e-mail the confirmation on request processing.

[75] The data are sent to the user by e-mail, simultaneously the database administrator is notified on the received data request and the request information is stored in the special log-file on the database server. Thus, the control of data requests with the database administrator is provided.

[76] The database collective users get the data via the routine data receiving. The sent data, their format and periodicity of sending are established by the arrangement with customers. Also depending on requirements and opportunities of customers the data transfer can be provided via e-mail or via the ftp-server. So, the data of geomagnetic field variations are daily transferred via e-mail to the Institut de Physique du Globe de Paris (France) and via the ftp-protocol to the Lancaster University (Great Britain).

[77] Because the slow Internet access to the geophysical observatories, located far from large towns, the mirrors of database site are created to improve the Internet access to the database. The web site of Borok Geophysical Observatory database (http://geobrk.adm.yar.ru:1352) has the mirror (http://geodata.borok.ru), located on the web server of Network Information Center of Space Research Institute (Moscow). The mirror is the full-function copy of the original web site of the database of middle-latitude Borok Geophysical Observatory, providing the graphic data, programs of generation of display pages, the data request forms, the database manuals and help information. The geophysical data are not transferred to the mirror. When they are requested by the visitor of the mirror, the data requests are sent to the database web site to process by the web-site software.

[78] The access to the geophysical data via Internet can be provided by the International geophysical networks as well as by the geophysical observatories. Borok Geophysical Observatory is the member of the Sub-Auroral Magnetometers Network (SAMNET) and the International near Real Time Magnetic Observatories Network (INTERMAGNET).

[79] Originally the data on magnetic field variations, digitizing by the SAMNET data logging system, were collected on the ZIP-disk and were transferred to the main server of SAMNET by the operator each week. In 2001 magnetic station SAMNET has been included in a local data logging network that has allowed to accumulate the registered data in the database server and to make daily automatic data sending via e-mail to the main server of SAMNET. Since 2003 the observation data are sent to the main server of SAMNET, located in the Lancaster University (http://www.dcs.lancs.ac.uk/iono/samnet) via ftp-report each day.

[80] The standard automatic magnetic observatory INTERMAGNET, installed in Borok Geophysical Observatory, includes vector fluxgate-magnetometer to measure three components of the geomagnetic field, scalar proton magnetometer to measure the magnetic field total value, GPS to synchronize the measurement data with universal time, power supply units, the electronic equipment and the data logging computer. Geomagnetic measurements are carried out with the resolution 0.1 nT. The sampling rate of scalar magnetometer is 1 minute. The data from vector magnetometer are read each 5 s, are filtered by the Gauss smoothing filter, centered in the minute interval. The received minute data of the geomagnetic field observation are collected in the diskette and are transferred to the database server manually each day, whence the data are automatically sent via e-mail to the geomagnetic information node in the Institut de Physique du Globe de Paris (http://obsmag.ipgp.jussieu.fr). Within the framework of INTERMAGNET program Borok Geophysical Observatory staff make the geomagnetic field absolute measurements two times per week. The results of these measurements are necessary to check and correct the data coming from the automatic magnetic observatory. The data of absolute measurements are weekly sent to the Institut de Physique du Globe de Paris via e-mail.