[en] The cell lines 679, 679-29 and 622-46 of L. erythrorhizon could be selected on LS agar medium for the production shikonin in cell suspension culture. The shikonin was increased moderately in suspension culture of cell line 622-46 in LS liquid medium containing BA 2 mg·L^-1 and IAA 0.2 mg·L^-1 in the dark, and was increased by adding 1 μM Cu²⁺ and 100 μM methyl jasmonate The accumulation of shikonin in the liquid medium was increased significantly by 2 Gy irradiation to callus of cell line 622-46 and culture in LS liquid medium containing BA 2 mg·L^-1 and IAA 0.2 mg·L^-1 in the dark and shikonin in cell debris was higher by 16 Gy irradiation. The activity of p-hydroxybenzoate geranyltransferase was increased by irradiation of 2 Gy and 16 Gy of γ radiation. Seedling hypocotyles of L. erythrorhizon were infected with Agrogacterium rhizogenes strain 15834 harboring a binary vector with an intron bearing the GUS (β-glucuronidase) gene driven by cauliflower mosaic virus (CaMV) 35S promotor as well as the HPT (hygromycin phosphotransferase) gene as the selection marker. Hairy roots isolated were hygromycin resistant and had integrated GUS gene in DNA. The root tip grown on M-9 medium showed normal pigment production pattern in border cells and root hairs

[en] Inspection and repair of tower structure and lift, instrument calibration have been done. Wireless data transmission to MIPS (Meteorological Information Processing System) has been done after collection in the DAS where environmental assessment can be done by the developed simulation programs in both cases of normal operation and emergency. Wind direction, wind speed, temperature, humidity at 67m, 27m, and 10m height and temperature, humidity, atmospheric pressure, solar radiation, precipitation, and visibility at surface have been measured analyzed with statistical methods. At the site, the prevailing wind directions were SW in spring and summer, NNW in winter season. (author). 6 refs., 9 tabs., 4 figs

[en] In this experiment, callus growth of L. erythrorhizon was increased by exposing to light but the shikonin production was increased in darkness condition and the effects could be increased by irradiation of low dose of gamma radiation. These results suggest that callus growth was the highest when callus was irradiated by 8 Gy of γ-ray and cultured on LS medium contained 2 mg/L BA and 2 mg/L NAA under 16 hours day light, however the production of shikonin form callus of L. erythrorhizon could be accelerated by irradiation of low dose gamma radiation like as 2 Gy and culture of the callus on M-9 medium in darkness. In suspension culture, shikonin production did not increased in proportion to the growth of cell, and the shikonin was increased by 30 Gy of γ-ray irradiation

[en] A radiological dose assessment system named FADAS has been developed. This system is necessary to estimated the radiological consequences against a nuclear accident. Mass-consistent wind field module was adopted for the generation of wind field over the whole domain using the several measured wind data. Random-walk dispersion module is used for the calculation of the distribution of radionuclides in the atmosphere. And volume-equivalent numerical integration method has been developed for the assessment of external gamma exposure given from a randomly distributed radioactive materials and a dose data library has been made for rapid calculation. Field tracer experiments have been carried out for the purpose of analyzing the site-specific meteorological characteristics and increasing the accuracy of wind field generation and atmospheric dispersion module of FADAS. At first, field tracer experiment was carried out over flat terrain covered with rice fields using the gas samplers which were designed and manufactured by the staffs of KAERI. The sampled gas was analyzed using gas chromatograph. SODAR and airsonde were used to measure the upper wind. Korean emergency preparedness system CARE was integrated at Kori 4 nuclear power plants in 1995. One of the main functions of CARE is to estimate the radiological dose. The developed real-time dose assessment system FADAS was adopted in CARE as a tool for the radiological dose assessment. (author). 79 refs., 52 tabs., 94 figs

[en] Highlights: • Analysis of PE-ALD grown HfON thin films using NH_3 and N_2 plasmas. • PE-ALD grown HfON film showed high dielectric constant and thermal stability. • PE-ALD grown HfON film suppressed the interfacial layer. • High leakage current of HfON film was caused by bandgap lowing and band offset. - Abstract: The structural and electrical characteristics of in-situ nitrogen-incorporated plasma enhanced atomic layer deposition (PE-ALD) HfO_xN_y thin films using NH_3 and N_2 plasmas as reactants were comparatively studied. The HfO_xN_y test structures prepared using NH_3 and N_2 plasmas were analyzed by X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and high resolution transmission electron microscopy (HR-TEM) to investigate the chemical composition, crystallinity, and cross-sectional layers including the interfacial layer, respectively. By utilizing NH_3 and N_2 plasmas, the nitrogen-incorporated HfO_xN_y thin films fabricated by in-situ PE-ALD showed a high dielectric constant and thermal stability, which suppresses the interfacial layer and increases the crystallization temperature. The high leakage current densities of the HfO_xN_y thin film test structures fabricated using NH_3 and N_2 plasmas caused by lowering the energy bandgap and band offset are related to the Hf−N bond ratio and dielectric constant

[en] This study is focused on the study of diffusion in the complex terrain such as in Korea which has mountainous region. To compensate the vertical diffusion coefficients in the Pasquil-Gifford curves, the Gaussian model was compared with the numerical diffusion model using a variational technique. Next, early and chronic exposure doses were calculated with the computed coefficient according to the WASH-1400 scenario. The compensation of vertical dispersion coefficient in two-dimensional x-z plane has been accomplished by comparing the Gaussian plume model with numerical diffusion model. The results show that the concentrations of radioactive effluents over complex terrain are more diluted than those expected over flat terrain. Acute and chronic exposure in the PWR design basis accident-class 8 were analyzed using the CRAC-2 subroutines by the above diffusion coefficient. (Author)

[en] A real-time dose assessment system has been proposed for the rapid estimating of the hazard of a nuclear accident. A mass-consistent wind field generation model has been developed. This wind field generation model can handle the meteorological data transferred from several meteorological posts. Field tracer experiment was carried out with the aim of the specification of the characteristics of Korean micro meteorology and the increasement of the accuracy of the diffusion model. As tracer gas UF₆ was used and 50 persons were dispatched over the flat area of 1 km radius for sampling. The sampled gas was analysed by gas-chromatographer. (Author)

[en] Inspection and repair of tower structure and lift, instrument calibration have been done. Wireless data transmission to MIPS(Meteorological Information Processing System) has been done after collection in the DAS where environmental assessment can be done by the developed simulation programs in both cases of normal operation and emergency. Wind direction, wind speed, temperature, humidity at 67m, 27m, and 10m height and temperature, humidity, atmospheric pressure, solar radiation, precipitation, and visibility at surface have been measured and analyzed with statistical methods. At the site, the prevailing wind directions were SW in spring and summer, NNW in winter season. The calm distributed 28.6% at 67m, 20.5% at 27m, 39.2% at 10m height. 9 tabs., 4 figs., 6 refs. (Author)

[en] Cheap and clean energy can be supplied with nuclear power plant whose accident probability is very low comparing with that of the other industrial facilities. However, the consequences of severe accident of nuclear power plant may result in a critical impact on population and ecosystem over a wide area due to the radioactive effluents released into the atmosphere as was in the case of the Chernobyl accident. Therefore, it is necessary to prepare an effective computer analysis system for real-time dose assessment against a potential severe accident of nuclear facility. The objective of this study is a development of the real-time assessment system of environmental exposure dose in an emergency and the installation of its prototype system. Wind field model satisfying the mass conservation and Monte Carlo diffusion model to save computing time were developed in order to assess real-time diffusion of radioactive effluents in an accident. Comparing studies were done in 3 kinds of typical topographic situation dependent on every atmospheric stability. Data library of exposure doses was documented by several computer calculation so that computation time could be reduced considerably. These results of the computation with data library showed a good agreement with the real calculation by the existing mode in which numerical integration model was used. And a graphic package was established that enabled to display the wind vector, concentration field of radioactives, and distribution of exposure dose every time step on the color graphic terminal. Work station was composed of host computer CDC-CYBER, graphic application processor - TEK 4301, graphic CRT - TEK 4125 and hard copier - TEK 4693 D. (Author)

[en] The computer program REDA(Real-time External Dose Assessment) was developed for the calculation of external gamma doses from radioactive materials in the three dimensional space. Three dimensional integration is necessary in this calculation, but it is very difficult and tedious job to get solutions, due to the complexity of the integral function. In the REDA the hexahedron cell in the atmosphere was assumed as a uniform sphere for the simplification of calculation, and thus triple integration was transformed into a single integration. After obtaining the distribution of radioactive materials with the wind field generating model and the advection-diffusion model, the external gamma dose rates were calculated with the REDA. For the validation of the REDA, the results were compared with those obtained with the model in which the hexahedron cell was assumed as a point source