Thermal Analysis of Biological Tissues Exposed To Electromagnetic Fields by Using Pennes' Bio-Heat Transfer Equation

In this paper, a complete electromagnetic and thermal analysis has been performed based on the Pennes’ bioheat transfer equation. Although there are many studies on the solution of Pennes Bio Heat Transfer Equation (BHTE) in the literature, most of these studies are based on numerical methods. In this study, a mathematically different approach is adopted, which makes this study different from other studies in the literature. Moreover, any numerical method is not utilized in this paper. The analytic solutions have been used to investigate the effects of the thermal diffusivity and the temperature-dependent perfusion component on the temperature distribution. The analytical expression obtained can provide a good knowledge of thermal behaviour of living tissues. The results present that; thermal behaviour of any biological tissue can be evaluated with the help of Pennes’ BHTE. Also, derived analytic analysis of the BHTE can be used for any tissue. Additionally, the results present that the analytic solution of BHTE is so valuable for the thermal behaviour research of any biological tissue. Topics such as thermal parameters measurement, and clinical therapy can be analysed by utilizing this study.&nbsp;</p

Determination of Electrical Values of Tissue Equivalent Liquids Prepared for 900 MHz Frequency by Using Soft Computing Methods

In this paper, an application of artificial neural network (ANN) for the prediction of electrical parameters in a human brain equivalent liquid (BEL), resulting from mixing different chemicals is presented. In the first phase of the study, different chemicals are used to produce the best BEL that meets the electrical values of IEEE 1528. 17 different chemicals are used by trying different combinations. After the experimental phase of study, electrical values of the BELs are measured for 900 MHz that was used in GSM communications. It is possible to prepare thousands of different tissue-like liquids with the 17 different chemicals used in this study. However, it is practically impossible to prepare thousands of tissue-like fluids and is not suitable in terms of scientific working principles. Therefore, the use of ANN is found to be very useful in terms of the prediction of electrical values of the BELs. This study is the first in the literature in which ANN is used to determine the electrical properties of chemicals. Moreover, the success of ANN in this study proved that the electrical values of all liquids with a determined stoichiometry can be determined by using soft computing methods.</p

Development of the GSM System in Turkey and The Role of Base Stations on Electromagnetic Pollution

The importance and the use of mobile communication systems are getting increasing attention worldwide. The use of mobile communication systems is shown as one of the biggest factor of electromagnetic force and intensity. World Health Organization and the other organizations have published many papers about this topic. A number of experts, especially in the developed countries, have stressed the risk of the electromagnetic pollution. Although using mobile phone is a personal preference, the establishment and the planning of the base station is not under control. In this viewpoint, we realized a number of measurements about the GSM 900 and DCS 1800 systems in Erciyes University. As a first part of this study, we employed a spectrum analyzer with a directional antenna for the determination of the electromagnetic pollution emitted by the base stations. Then the measured values are compared with the critical values that were reported by national and international organizations. Finally in the last part of this study the reader will find the possible effects of increasing the number of base stations on the electromagnetic pollution