[en] The evolution of the MgO surface in a plasma display panel (PDP) at the initial stage of panel aging has been investigated. The experimental result shows a strong dependence of the surface modification on the waveform of the sustain voltage pulse in the aging process. The MgO surface ws examined with a scanning electron microscopy (SEM) after panel aging for 20 hours. The modified surface area in a cell became broader and more uniform as the rising time of the aging pulse increased, which resulted in a bigger operating voltage margin and an improved panel life. Our results also imply that the optimum aging condition should vary the dimension of the discharge cell changes

No abstract available

No abstract available

[en] Minimum magnitudes (M_c) for estimation of seismicity parameters were analyzed for the earthquake catalog of Korea Meteorological Agency (KMA). The temporal variation of earthquake frequency suggests that a proper M_c be 3.0 for the whole southern part of the Korean Peninsula. The b-value with M_c of 3.0 is estimated to be 1.11, which is larger than those of the previous studies. To see the spatial variation of M_c, the southern part of the peninsula were divided into grids of 0.1 x 0.1 degree. At the greater portion of grid points, the local earthquake catalogs do not satisfy given statistical criteria. The grid points whose local earthquake catalogs meet the criteria mostly distribute in the eastern part. M_c at these points ranges 2.4 to 3.5

[en] Hydrocarbon reserve exploration in deep water is done by geophysical surveys. Previously seismic geophysical surveys were explicitly used but it has indistinct results for both water and hydrocarbon saturated reservoir. Recent development for the detection of hydrocarbon reservoir in deeper water is Marine Controlled Source Electromagnetic (MCSEM) geophysical survey. MCSEM is sensitive to electrical conductivity of rocks by which it can differentiate between hydrocarbon reservoir and water saturated reservoir. MCSEM survey geometry put vital role and may causes for anomalies in synthetic data. Consequentially MCSEM is sensitive to survey geometry (e.g. source dipping, rotation and speed, receivers' orientation etc) which causes anomalies. The interpretation for delineating subsurface structure from survey data need to well understand the effects of survey geometry anomalies. Forward modelling is an alternative rather real time survey to study the aforementioned anomalies. In this paper finite difference method (FDM) is implemented for 2D forward modelling in the sense of qualitative understanding to how induced Electromagnetic (EM) signal changes its overall pattern while interact with physical earth properties. A stratified earth structure is developed and modelled in MatLabTM software to study the behaviour of EM field with physical earth properties. Obtained results of 2D geological models are also discussed in this paper. (author)

[en] This study have been carried out for attempting to develop the minimum requirements of testing methods and procedures for determining engineering properties for foundation bedrock at NPP site. As a first phase study, for the compressive strength and deformation modulus of rock important to the safety evaluation of the bearing capacity and settlement of the foundation, the testing methods and procedures for determining the two characteristic values were reviewed and comparison between each value of the sites under studying was carried out. The data originated from Wolsong 1 spent fuel dry storage site and the NPP sites of Yonggwang 3 · 4, Wolsong 2·3·4, and Ulchin 3·4. Also, re-evaluation was made for the data excluded from original analysis, and especially re-calculation of rock mass deformation modulus of Wolsong unit 2 was conducted by using the settlement data. The analysis result show that the uniaxial compressive and point load tests had been conducted for compressive strength and the jack test, hydraulic pressure meter test, and correlation methods using RQD, RMR, and velocity index were conducted for rock mass deformation modulus. It is also found that there was a tendency to decide characteristic values by selecting the lower value among various test results rather than considering the credibility of the test results

[en] Fault geo-information analysis project is a typical multidisciplinary study, which includes various geological specialties. Majority of the information produced by this study are spatial in nature. Therefore an effective geological information system, gathered by project participants, is essential for organization and analyses of the data. To treat the spatial data properly, basic maps, such as topographic, geologic, shade and satellite image maps are provided. This study therefore, aims to produce the necessary digital maps and an effective s/w for data storage and analyses. Maps. S/W of the previously made geological system is updated. Known problems and functional defects should be upgraded as well. Currently upgraded s/w is efficient enough for various geological information. Therefore a competent training program for s/w usage should be organized and the wide use of the s/w among participants should be encouraged. This report is written especially for the useful reference of field workers

[en] This paper reviews definitions and technical backgrounds of 'capable fault' used in the United States, Japan, China, and IAEA, constraint to age criteria, with an these definitions, eventually to apply it to the developing regulatory standard for nuclear power plant (NPP hereafter) siting in Korea

[en] This paper reviews regulatory standards of geological and seismological investigations applied to nuclear power plant (NPP hereafter) siting in U.S., Japan, China and IAEA, and considers a possible guideline to the ranges and depth of the investigation for NPP siting in Korea, considering geological characteristics revealed from recently performed multidisciplinary researches at and around Korean NPP sites

[en] This paper proposes Korean site-specific criteria based on a review of capable fault criteria used in the United States, Japan, China, and IAEA, and the result of a multi purpose research project to characterize Korean tectonic environment