The natural radioactivity levels of Kirkuk oil field are studied using high resolution gamma rays spectrometry. For this reason, soil samples were collected from three sites in the Iraq North Oil Company: Baba Gurgur, Shurau and old process plant (Terkiz). The activity concentrations obtained for 238 U-series ( 226 Ra, 214 Pb, and 214 Bi), 232 Th-series ( 228 Ac, 212 Pb, and 208 Tl) and 40 K. The results have been compared with the worldwide average values.The radium equivalent activity (Ra eq ), the absorbed dose rate (D), the annual effective dose rate (AEDE), the external hazard (H ex ), the internal hazard (H in ) and Gamma radiation representative level Index (I g ) were also obtained and compared with the international recommended values.

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This paper concerned with simulating the behavior of designed control system that tries to govern robot to safely passing a path containing moving obstacle ahead. The used robot carried some specific sensors are used to sense the existence of obstacles along the moving path, these sensors are IR sensor that used to detect the obstacle and visual sensor that used to measure the size and the distance for the obstacle. In order to overcome the obstacle, the controller assumes new transient away point at the far side of the obstacle, and guides the robot to pass through that point. The position of such transient point is depending on the size and direction of the obstacle. Then, whenever the robot close to the transient point, the controller guides the robot to identify the intended path again. This algorithm enables the robot to move far away from the moving obstacle and then back it into planned path.

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Gamma ray buildup factor for two shielding materials, water (Z eff ¼ 7.42) and graphite (Z ¼ 6) for isotropic plane source normally incident within the energy range 4e10 MeV and up to 5 thickness mean free path has been studied. This research has been achieved by writing a simulation computer program in (Visual Basic language version G) and applied depending on Monte Carlo simulation method. The contribution of annihilation effect on the calculation of gamma ray dose buildup factor has been studied for both graphite and water. The results indicated that the calculated values of dose buildup for plane source, when ignoring the contribution of pair production, is less in comparison with the case when the contribution of pair production is taken into consideration. However, the contribution of Compton effect is still more predominant than the effect of annihilation within the range of energy (4e10) MeV.