Properties of bentonite, mainly used as buffer and/or backfill materials, will evolve with time due to thermo-hydro-mechanical-chemical (THMC) processes, which could deteriorate the long-term integrity of the engineered barrier system. In particular, degradation of the backfill in the evolution processes makes it impossible to sufficiently perform the safety functions assigned to prevent groundwater infiltration and retard radionuclide transport. To phenomenologically understand the performance degradation to be caused by evolution, it is essential to conduct the demonstration test for backfill material under the deep geological disposal environment. Accordingly, in this paper, we suggest types of tests and items to be measured for identifying the performance evolution of backfill for the Deep Geological Repository (DGR) in Korea, based on the review results on the performance assessment methodology conducted for the operating license application in Finland. Some of insights derived from reviewing the Finnish case are as follows: 1) The THMC evolution characteristics of backfill material are mainly originated from hydro-mechanical and/or hydrochemical processes driven by the groundwater behavior. 2) These evolutions could occur immediately upon installation of backfill materials and vary depending on characteristics of backfill and groundwater. 3) Through the demonstration experiments with various scales, the hydro-mechanical evolution (e.g. advection and mechanical erosion) of the backfill due to changes in hydraulic behavior could be identified. 4) The hydro-chemical evolution (e.g. alteration and microbial activity) could be identified by analyzing the fully-saturated backfill after completing the experiment. Given the findings, it is judged that the following studies should be first conducted for the candidate backfill materials of the domestic DGR. a) Lab-scale experiment: Measurement for dry density and swelling pressure due to saturation of various backfill materials, time required to reach full saturation, and change in hydraulic conductivity with injection pressure. b) Pilot-scale experiment: Measurement for the mass loss due to erosion; Investigation on the fracture (piping channel) forming and resealing in the saturation process; Identification of the hydro-mechanical evolution with the test scale. c) Post-experiment dismantling analysis for saturated backfill: Measurement of dry density, and contents of organic and harmful substances; Investigation of water content distribution and homogenization of density differences; Identification of the hydro-chemical evolution with groundwater conditions. The results of this study could be directly used to establishing the experimental plan for verifying performance of backfill materials of DGR in Korea, provided that the domestic data such as facility design and site characteristics (including information on groundwater) are acquired.

본 연구는 당대 시인이 시각적 이미지를 접하는 수단, 즉 ‘보다’의 의미를 나타내 는 시어 중에서 ‘뒤돌다’라는 특별한 의미소를 지닌 ‘顧’라는 시어를 집중적으로 분석 했다. 뒤를 돌아보는 행위의 대상은 당시에서 주로 시인 자신, 자신을 알아봐주는 지 기, 본인을 등용할 수 있는 집권자, 자신을 상징하는 그림자, 과거와 역사, 자신의 고 향 혹은 꿈을 이룰 수 있는 도성 등이 있다. 이 대상들은 모두 ‘자신’이란 개념과 관 련이 있었고, 시인이 시 안에 담은 ‘자신’의 정서와 긴밀한 관계를 맺고 있다. 본고는 이러한 대상들을 뒤돌아보았을 때 ‘顧’가 어떠한 의미를 나타내는지 고찰했다. 또한, ‘뒤’ 또는 ‘후방’이라는 ‘顧’의 의미소가 나타내는 부정적인 뉘앙스와 개념적 은유에 입각하여 ‘顧’의 의미가 시인의 감정 및 사상과 정확히 어떠한 관계가 있고, ‘顧’자가 어째서 시인의 처지와 정서를 드러내는 데 최적화되어 있는지 문학적 각도에서 연구 했다.

제자백가의 각 학파는 비록 주장하는 사상이 서로 다를지라도 동일 사물에 대해서 언급하여 의견을 전달하는 경우도 상당히 많다. 그러한 사물 중에는 발명품이나 도구도 포함되는데, 본고는 그 가운데 規矩, 즉 그림쇠와 곡자를 고찰하였다. 구체적으로는 제자백가의 대표적인 사상가들이 規矩를 어떠한 의미로 자신의 문장에서 거론 하였는지, 이 도구들이 그들이 주장하는 내용과 어떠한 연관이 있는지, 작가간에 規 矩란 용어를 제시하는 방식에 있어서 공통점이 있는지 등 문제에 대해 분석했다. 또한, 사상가들이 본인들의 담론에서 規矩를 선택한 이유와, 그것을 통해서 추측 가능 한 당시의 사회상, 아울러 당시 사람들이 세계를 어떤 식으로 인식했는지 분석했다.

Despite the accident rate for fishing vessels accounts for 70% of all maritime accidents, few studies on such accidents have been done and most of the them mainly focus on causes and mitigation policies to reduce that accident rate. Thus, this risk analysis on sea accidents is the first to be performed for the successful and efficient implementation of accident reducing measures. In risk analysis, risk is calculated based on the combination of frequency and the consequence of an accident, and is usually expressed as a single number. However, there exists uncertainty in the risk calculation process if one uses a limited number of data for analysis. Therefore, in the study we propose a probabilistic simulation method to forecast risk not as a single number, but in a range of possible risk values. For the capability of the proposed method, using the criteria with the ALARP region, we show the possible risk values spanning across the different risk regions, whereas the single risk value calculated from the existing method lies in one of the risk regions. Therefore, a decision maker could employ appropriate risk mitigation options to handle the risks lying in different regions. For this study, we used fishing vessel accident data from 1988 to 2016.

Bacterial diversity based on the denaturing gradient gel electrophoresis (DGGE) analysis of PCR-amplified 16S rRNA gene sequences was determined for soil samples from two abandoned mine sites and the corresponding enrichment cultures using soil sample as

Ultrafine copper powder was prepared from slurry with hydrazine, a reductant, under . The influence of various reaction parameters such as temperature, reaction time, molar ratio of , PvP and NaOH to Cu in aqueous solution had been studied on the morphology and powder phase of Cu powders obtained. The production ratio of Cu from CuO was increased with the ratio of and the temperature. When the ratio of was higher than 2.5 and the temperature was higher than , CuO was completely reduced into Cu within 40 min. The crystalline size of Cu obtained became fine as the temperature increase, whereas the aggregation degree of particles was increased with the reaction time. The morphology of Cu powder depended on that of the precursor of CuO and processing conditions. The average particle size was about

Monodispersed flaky silver powder was obtained by controlling the ratios of and Agin in a mixed solution of ethylene glycol and ammonia with an addition of PVP. The effects of on its morphology and size were investigated. In molar ratio was found to be an important reaction factor for the nucleation and crystal growth of Ag powder. The synthesis of flaky powder was optimized at over 6 of molar ratio increased, the size of precipitates was increased regardless of the amount of Pt. In the absence of , the morphology and size of reduced Ag powder were found to be irregular in shape in diameter. However, homogenized fine Ag powder was obtained due to heterogeneous nucleation when used as a cat-alyst, and flaky one was synthesized with the addition of Pt over of Pt/Ag.

A strategic decision making on location selection for product transportation includes many tangible and untangible factors. To choose the best locations is a difficult job in the sense that objectives usually conflict with each other. In this paper, we consider a multi stage multi criteria transshipment problem with different types of items to be transported from the sources to the destination points. For the optimization of the problem, a goal programming formulation will be presented in which the location selection for each product type will be determined under the multi objective criteria. In the study, we generalize the transshipment model with a variety of product types and finite number of different intermediate nodes between origins and destinations. For the selection of the criteria we selected the costs(fixed cost and transportation cost), location numbers, and unsatisfied demand for each type of products in multi stage transportation, which are the main goals in transshipment modelling problems. The related conditions are also modelled through linear formats.