The electromagnetic wave absorption characteristics of composite cement-based building material have attracted much interest in recent times. Researchers have mainly focused on the 2 GHz to 12 GHz frequency range. Mobile and wireless communication systems use frequencies from 800 MHz upwards. The determination of characteristics such as reflection loss, absorption, attenuation and shielding effectiveness are crucial in the evaluation and development of these materials for the building industry. Absorption is an indication of how much of the EMW energy enters the material. Attenuation indicates how much of the absorbed energy is converted into other forms of energy by the material. Shielding effectiveness (SE) is a combination of reflection loss, attenuation and multiple internal reflections and attenuations. This research determined these characteristics by measuring the S11 and S21 parameters of the composite cement-based material in the GSM and WiFi frequency bands. The time domain gating function of a vector network analyser is applied to measure the reflection from the material. The data was then used to obtain the reflection and absorption losses in the frequency bands. The transmission loss was measured by placing the sample in the propagation path between two antennas. MnZn-ferrite and electrolytic manganese dioxide in powder form were evaluated as absorber material to increase the permeability of the cement-based material to improve absorption and attenuation capabilities to create a cost-effective practical electromagnetic wave absorber. The compound of the cement-based material was cement, sifted river sand and filler powder. The results achieved in the research showed the uniqueness of electrolytic manganese dioxide as filler in composite cement based material for electromagnetic wave shielding effectiveness improvement. The combined measurement techniques used in this research were uniquely used to determine the required electromagnetic wave absorption characteristics and shielding effectiveness of 10 dB was measured in the GSM850 and GSM900 frequency bands. / Dissertation (MEng)--University of Pretoria, 2013. / gm2014 / Electrical, Electronic and Computer Engineering / unrestricted

This thesis deals with design, development and testing of device for collecting fly data in ultralight airplane or helicopter. The basic collected value is a count of fly hours of each pilot. Additional fly data are latitude, longitude and altitude. Purpose of this device is a fair pricing for use of the airplane. Another utilization is in analysis of flight path or in pilot training. This device is succesfully made from miniature computer Raspberry Pi and uses GPS data. A reader will be informed about aviation regulations, embedded systems, global positioning system and wireless internet connection.

This work deals with connecting remote devices measure data of various types from physical quantities such as a temperature, a humidity to data displaying CPU or memory usage of the system to the user. The system uses Blockly to controlling logic and dependencies between devices. In the work is used lots of technologies for examples: MQTT, Websockets, GSM, Lightweight Mesh and others. The system is based on microservice which named is Flask. Flask service is an application interface for HTTP services of Python programming language. This can provide measured data by graphs and predefined components for viewing data. For controlling system was used single-board computer Raspberry Pi with a multitouch 7-inch display.

This diploma thesis is based around SMS module for free e-commerce solution. Because of big amount of e-commerce platforms, this dissertation focuses on creating generic solution of SMS module, which will be easily modifiable across individual platforms. The SMS module is used to notify administrators or customers about order changes. Module also contains effective SMS marketing tool, which allows, for a low price, targeting ads in a form of SMS. Including a whole lot of other functions, like statistics, history of outcoming messages, optional language mutation and other settings requested by customers.

Document contains informations about authentication, encryption, data integrity and data authenticity. Next part includes description of well know cryptography protocols, their functions and also their weaknesses. All of these acquired informations were used in concept and final software support for teaching of cryptography protocols, which is able to run on clasic web-browser. Thats why the application was designed as web PHP pages using JavaScript and AJAX, which ensures plaform and OS architecture independency. Besides the descripted and ilustrated part of application there are also interactive parts and animations. The last period contains description of education software and its functions. Source code can be found on the appended CD.

The objective of the diploma thesis is to design a device for positioning of mobile devices using GPS satellites. When coordinates are acquired they can be sent via the GSM network to a user's cell phone or to an SQL server. A web interface has been designed to access the stored data and to show the current device position and the history. This position datalogging system can be used for monitoring vehicles as well as a security system for cars.

This Graduation Theses dissertate about a creation of a drawing documentation at the professional CAE EPLAN Electric P8 system. One original solution of a remote control and of motor-generator monitoring with a mobile phone, short SMS-aided in this case, was used as an example of the drawing documentation. As has allready been noted in previous Bachelor Thesis, this application can be use not only for a remote control of a motor-generator, but this solution is suitable for other electric devices too, which are out of reach of an attendance for example. In our case a generator with 6kVA power is concerned with rated output voltage 230Vac and rated current 25A. The system of a remote control has the advantage that it is created from standard components (electric instruments, a PLC – programmable automat, a GSM modem, an operating panel and the respective program in the PLC).

The master’s thesis describes IMS (IP Multimedia Subsystem) in terms of IMS core ele- ments (functional description, different implementation, signaling etc.) Communication protocols SIP and DIAMETER, together with SNMP protocol, which is used for collecting data are briefly described in this thesis.Thesis is also describing various IMS projects to- gether with Open IMS project, for whom was this surveillance system designed. Next part deals with architecture design of surveillance system along with management options implemented in surveillance system for users and administrators. The main part of master’s thesis deals with the description of the surveillance system for the experimental school Open IMS network and describes the remote configuration of core elements and monitoring of network traffic, together with the monitoring servers performance. The most of the data in the designed surveillance system are processed into graphs, which are regularly updated. The final part of master’s thesis describes the configuration and implementation of monitoring tools MRTG and NfSen that were used in created web based surveillance system.

This master's thesis is focused on VoIP communications. It describes deploy of the operating system OpenWRT, analog interface of router Gigaset SX762 and GSM gateway for receiving or place calls. The paper describes the protocols involved in the communication and basic configuration elements. Deploying IP telephony enables to reduce the cost of operation and provides a number of additional functions.

This project deals with the problematics of self-powered universal GSM/GPRS module which is used for sensorical applications. The first part analyzes features of mobile networks and applying energy from the environment. The second section expalins the various parts and characteristic of their associated components together with some fundamental functions of the technology for possible realization of sensoric module. The third part describes plan for system realisation and fourth parth illustrates achiaved results.