Investigation of Natural Effective Gamma Dose Rates case study: Ardabil Province in Iran

Gamma rays pose enough energy to form charged particles and adversely affect human health. Since, the external exposure of human beings to natural environmental gamma radiation normally exceeds that from all man-made sources combined, natural background gamma dose rates and corresponding annual effective doses were determined for selected cities of Ardabil province from 2009 to 2010. Outdoor gamma dose rates were measured using an Ion Chamber Survey Meter in 105 locations in selected districts. Average absorbed dose for Ardabil, Sar-Ein, Germy, Neer, Shourabil Recreational Lake, and Kosar were determined as 265, 219, 344, 233, 352, and 358 nSvh-1, respectively. Although dose rates recorded for Germi and Kosar are comparable with some areas with high natural radiation background, however, the dose rates in other districts are well below the levels reported for such locations. Average annual effective dose due to indoor and outdoor gamma radiation for Ardabil province was estimated to be 1.73 (1.35-2.39) mSv, which is on average 2 times higher than the world population weighted average

Digital position and velocity determination in controlled drive systems

Motion control of robotic or manipulator joints, tool machines axes or more genrally of drive systems require accurate position, velocity and possibly acceleration control. Today, these controls are almost always realized using digital controllers. Therefore, digital position, velocity and accelleration informations must be precise and accurate. To mini mize the sensor numbers as well as the wiring, the velocity and accellereation informations are often numerically computed form the positino. Different algorithms can be used : simple difference, polynomial interpolation, ex-quad interpolation,extrapolator, observer. The type of sensor, its precision and its location as well as the sampling time and the used alghorithm strongly effect the quality of the computed quantities (velocity and/or accelleration) and therefore the control performance. This paper analyses the static dynamic performances of different digital position and velocity measurements

Assessment of Indoor Gamma Radiation and Related Annual Effective Dose in Zanjan, IRAN

"n "n "nBackgrounds and Objectives: Due to importance of ionizing radiation on human health, many studies have been performed to measure the background gamma radiation all around the world as well as some cities in lran. According to this fact that everybody spends almost 80% of his time in indoor areas, this study was carried out to measure the amount of background gamma radiation in indoor areas in Zanjan city located in northwest of Iran to determine the annual effective dose of the city residents."nMaterials and Methods: To determine the dose rate of background gamma radiation in indoors, 30 dwelling (in the main geographical directions and in the downtown areas) were selected. All of them were one floor and iron roofed. A Geiger-Muller detector (RDS-110) calibrated by Cs-137 was used in each livings room of each dwellings that performed in one meter far from the earth. In 30 minute 30 values was recorded. The mean value was considered as indoor gamma dose rate in each dwelling."nResults: The mean value of dose rate in Zanajn indoor areas due to gamma background radiation was determined 146±25 nGy/h. According to the results and findings in our previous study about gamma background radiation in outdoor areas in Zanjan, the annual effective dose was determined and 0.87 mSv for Zanjan city residents. "nConclusion: The annual effective dose of Zanjan city residents due to the gamma background radiation is 0.87 mSv that in comparison with UNSCEAR-2000 report is higher than the mean value for the world (0.48 mSv)

Natural radioactivity levels of 226Ra and 40K in soil of Zanjan province, Iran

Radioactivity concentration of naturally occurring radionuclides, 226Ra and 40K, in soil samples of Zanjan province, in north-west of Iran and from 21 geographical areas was measured by gamma spectrometry. The activity concentration of 226Ra ranged from 58.4±1.8 to 132±3.1 Bq kg-1 with the mean value of 88.5±22.9 Bq kg-1. The activity concentration of 40K ranged from 267±5.9 to 791±8.1 Bq kg-1 with the mean value of 497.4±162.6 Bq kg-1. The mean values for absorbed dose rate in air and annual effective dose were determined as 62.6±16.5 nGy h-1 and 0.076±0.02 mSv, respectively. © The Author 2010. Published by Oxford University Press. All rights reserved