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In this study, the design and implementation of a new portable thermoelectric generator of 100 W for low geothermal temperatures has been carried out. For this system, a new SCADA-based testing and measuring system equipped with special software has been developed and employed for the first time. Thus, effects of the hot-cold water flow rates, the temperature differences between the surfaces and the load resistance affecting output power and efficiency of the thermoelectric generator have been investigated by a single testing and measuring system device. In the established SCADA-based testing and measuring system, the hot-cold water flows passed throughout the surfaces of the thermoelectric generator were increased by up to 3.7 and 12.8 l/min, respectively. Then, the temperature difference between the surfaces of the thermoelectric generator was measured as 67°C. When the load resistance of the thermoelectric generator was about 15 Ω, the maximum power of the thermoelectric generator was obtained as 41.6 W and the conversion efficiency was calculated as 3.9%. Also, the SCADAbased testing and measuring system will open up a new stage in examination of various thermoelectric generators.

Many studies show that artificial hypothermia of brain in conditions of anesthesia with the rectal temperature lowered down to 33 degrees C produces pronounced prophylactic effect protecting the brain from anoxia. Out of the methods employed now in clinical practice for reducing the oxygen consumption by the cerebral tissue, the most efficacious is craniocerebral hypothermia (CCH). It is finding even more extensive application in cardiovascular surgery, neurosurgery, neurorenimatology and many other fields of medical practice. In this study, a microcontroller-based designed human brain hypothermia system (HBHS) is designed and constructed. The system is intended for cooling and heating the brain. HBHS consists of a thermoelectric hypothermic helmet, a control and a power unit. Helmet temperature is controlled by 8-bit PIC16F877 microcontroller which is programmed using MPLAB editor. Temperature is converted to 10-bit digital and is controlled automatically by the preset values which have been already entered in the microcontroller. Calibration is controlled and the working range is tested. Temperature of helmet is controlled between -5 and +46 degrees C by microcontroller, with the accuracy of +/-0.5 degrees C.