There are three questions arise in radioactivity measurements: (1) Dose the measured value originate from the radioactivity being present in the sample? (2) Is the measurement procedure suitable for the intended measurement purpose with respect to the requirements? (3) What is a range of values fairly sure our true value lies in with a specified probability? These three questions are answered by determining characteristic limits (decision threshold, detection limit and limits of the coverage interval), which are widely used as part of quality assurance in radioactivity measurements. In the past, numerous papers have focused on the questions in different ways, and have drawn a variety of conclusions about the meaning of the different characteristic limits using various terms and symbols. In recent years, substantial efforts were made in order to obtain a systematic and unified way to calculate and express these limits. As a result, the ISO 11929 Series which specify a procedure for calculation of the characteristic limits have been developed. This paper is focused on the calculations of characteristic limits for noble gas monitor (NGM204 monitor) that offers the continuous measurements of radioactive noble gases discharged from the stacks of the HANARO reactor facility. The calculations are based on the standard ISO 11929 as well as the traditional formulas provided by NUREG 1576, ANSI N42-18, ANSI N42-17 and DIN 25482. A comparison is made among the results obtained from the formulas given in each literature.

자기필터시스템을 이용한 원자로 냉각재로부터의 방사성 부식생성물 제거는 원자력 발전소의 운전 및 유지보수 종사자에 대한 방사선 피폭 준위를 낮추는 방법으로 많은 연구가 이루어지는 분야 중 하나이다. 그 결과, 보다 높은 신뢰성과 여과성능을 갖춘 자기필터를 개발하고자 수화학 분야에서는 많은 연구가 이루어지고 있다. 본 연구에서는 부식생성물의 자기적 성질을 이용하여 원자력 발전소 냉각재내의 방사성 부식생성물을 제거하기 위해 영구자석과 전자석 이 조합된 자기필터 시스템을 개발하였다. 영구자석은 부식생성물의 여과를 위해 사용되며 전자석은 아주 미세한 콜로이드 부식생성물 입자의 크기를 증가시키기 위한 응집에 이용된다. 선행 연구에서 영구자석만을 사용한 필터 실험결과 대부분의 부식생성물 입자에 대해 만족할만한 수준의 제거효율을 달성하였으며 특히, 크기가 5m 이상인 입자의 경우 제거효율은 90를 상회하였다. 전자석을 이용한 응집 실험결과 화학응집제의 첨가 없이 대부분의 부식생성물 입자가 전자기장에 의해 응집하여 크기가 5m 이상으로 증가되어 응집실험에 대해 전반적으로 만족스러운 결과를 도출하였다. 따라서, 영구자석과 전자석이 조합된 자기필터시스템은 방사성 부식생성물 제거를 위한효과적인 방법으로 높은 제거효율을 보여주리라 여겨진다.

방사성핵종의 특성, 섭취형태 그리고 내부피폭 감시주기는 작업자의 방사성핵종 섭취량 및 내부피폭선량 평가 결과에 중요한 영향을 줄 수 있다. 따라서 방사성핵종이 흡입섭취 될 경우 섭취형태(급성 또는 만성) 및 내부피폭 감시주기에 따른 섭취량 평가 오차를 계산하였다. 섭취 핵종으로는 /I(Type F), Cs(Type F), U(Type M, Type S)를 고려하였고, 방사능입자크기(AMAD)는 1 와 5 를 고려하였다. 섭취형태에 따라 평가된 섭취량의 상대오차는 방사성핵종, 흡수형태 그리고 내부피폭 감시주기에 따라 달랐으나, 입자크기에 의한 영향은 거의 없었다. 섭취형태 가정에 따른 섭취량 평가 오차를 10% 미만으로 줄일 수 있는 내부피폭 최대감시주기는 /I(Type F)에 대해 60일, Cs(Type F)에 대해 180일, U(Type M)에 대해 90일, 그리고 U(Type S)에 대해 360일로 나타났다.

정확한 in vitro 전사가 일어날 수 있는 진딧물의 세포추출액을 제조하였다. 전사를 직접 조절할 수 있는 단백질 인자를 규명하기 위하여 전사개시점과 그의 상류에 결합하는 DNA 결합단백질을 탐색했다. 전사개시점을 포함하는 단편 A(-194/23)에는 52kDa, 50kDa, 40kDa의 단백질들이 결합했으며 전사개시점 상류의 DNA 단편 B(-393/-263)에는 52kDa, 50kDa, 40kDa의 단백질들이 결합한 반면 DNA 단편 C(-263/-195)는 53kDa단백질만이 결합했다. 그리고 이들 DNA 결합단백질들의 DNA 결합 활성에는 양이온이 요구되었다.

It is assumed that air temperature and light intensity may influence thermal image of plants but little effort has been made to these environmental factors. We conducted this study to investigate the effects of these environmental factors on the thermal image of rice and thus to optimize the condition for thermal image acquisition for high-throughput screening of salt-tolerant rice. Rice (Oryza sativa cv. Chucheong-byeo) seedlings at the four-leaf stage were treated with 0, 50, and 100 mM of NaCl for salt stress. Thermal images (T420, FLIR, Sweden) were taken at 1 and 2 days after salt treatment under 4 different air temperatures and 3 light intensities. Thermal images were analyzed using FLIR Tools 3.1 (FLIR systems Inc., USA) and MATLAB 8.1 (The MathWorks Inc., USA). Rice leaf temperature increased significantly with increasing air temperature and light intensity, resulting in greater discrimination between salt-stressed and unstressed rice plants. Our results thus conclude that environmental conditions such as air temperature and light intensity affect rice thermal image and their optimization is essential for better image acquisition and high-throughput screening system based on thermal image analysis

The purpose of this study was to establish a system for plant fluorescence image acquisition and to verify the possibility of plant fluorescence image analysis as a non-destructive method to screen the salt tolerance of soybean (Glycine max). Two-weeks-old seedlings of soybean at the V1 growth stage were treated with 0, 50, and 100 mM of NaCl for salt stress and plant fluorescence images were taken by CCD camera (EOS-600D, Canon, Japan) equipped with band pass filter (XNiteBPB, LPD LLC, USA) at 0, 15, 30, 60, 120 and 240 second after blue light exposure at 1 day after treatment. Red color intensity was extracted using MatLab 8.1 (The MathWorks Inc., USA) for estimation of plant fluorescence intensity. Red color intensity of soybean image decreased 0 (F0-10) to 240 (F240-250) second after blue light exposure irrespective of NaCl concentration, while F0-10/F240-250 decreased with NaCl concentration, resulting in significant relationship with plant fluorescence (Fv/Fm) and salt stress intensity. Therefore, our results suggest that our plant fluorescence image acquisition and analysis methods can be a part of high-throughput screening system for salt tolerance of soybean varieties

This study was conducted to investigate plant body temperature response of soybean (Glycine max) to saline stress. Two-weeks-old seedlings of soybean in V1 growth stage were treated with 0, 10, 20, 40, 80 and 160 mM of NaCl for salt stress. Thermal images acquired using Flir T-420 (US) were obtained at 4 days after treatment. Soybean leaf temperature increased with increasing NaCl concentration, resulting in significant positive correlation between soybean leaf temperature and stress intensity (P < 0.01). Leaf temperature of soybean was significantly different at 160 mM of NaCl, where no visual symptom was observed. Therefore, soybean leaf temperature can be used for evaluating the response of soybean to salt stress as a non-destructive and phenomic parameter. Non-destructive diagnosis of soybean leaf temperature may be a key parameter in a high throughput screening (HTS) system in breeding program for salt stress tolerance soybean cultivars.