For Korean nuclear fuel cycle project, it is necessary to design and evaluate the integrity of spent fuel storage. For the design and evaluation of spent fuel storage, it is necessary to evaluate the properties of various materials used in spent fuel storage. The materials previously considered in the design of nuclear power plants were limited to static properties and were listed in design and manufacturing code and standards. However, for the evaluation of the storage containers in scenarios such as transportation and events, dynamic material property evaluations are required. Research on the dynamic properties of materials is generally conducted in the fields of automotive and aerospace, and most of the studies are on metal materials under sheet conditions. Since the structural materials of the storage containers for used nuclear fuel are mostly composed of thick materials, consideration should be given to property evaluation methodology and quantitative comparison. In this study, the mechanical properties of stainless steel material with canister application were evaluated according to the strain rate, and the crack resistance evaluation was also performed. It was confirmed the changes in strength and crack resistance according to the increase in strain rate and observed differences in microstructural hardening behavior.

This study has been conducted to investigate the North Korea water supply system. For this purpose, laws and regulations concerning the North Korea water utilities were analyzed. According to this study, the water supply system of North Korea is similar to that of South Korea. The major difference between these two systems lies in the national water supplier: South Korea has the national water supplier as well as the municipal suppliers, while there is no national water supplier in North Korea. It is noted that the North Korean water utilities depend on outside suppliers for resources necessary for water production such as electricity, chemicals, spare parts, etc. This could damage the North Korean water utilities. If required resources were not delivered properly (deficient quantity and/or at delayed timing), the water suppliers would encounter difficulties in water production.

It is investigated in this study how the water supply system has been developed in North Korea. Articles published in the Rodong Newspaper (North Korea official newspaper) were mainly reviewed for this purpose. It was found in this study that the development of the water supply system in the North Korea was affected by their socioeconomic situations. Their water supply development was categorized into six groups in this study since the first water supply system built in Pyongyang (1910); Occupation period (1910~1945); Introduction period (1946~1950); Restoration period (1951~1960); Advancement period (1961~1970); New village period (1971~1974); Depression period (1974~).

In this study, a MWCNT(multi-wall carbon nanotube) was added to polysulfone(PSf) support layer to improve flux of TFC(thin film composite) RO(reverse osmosis) membrane. Two different kinds of MWCNT were used. Surfaces of some MWCNTs were modified hydrophilically through acid treatment, while those of other MWCNTs were modified through heat treatment to maintain their hydrophobicity. MWCNT/PSf support layer was prepared by adding PSf to the NMP mixed solvent containing 0.1 wt% MWCNTs using a phase inversion method. The surface porosity of the MWCNT/PSf support increased by 42~46% while its surface pore size being maintained. The TFC RO membrane made of MWCNT/PSf support layer showed a 20% flux increase while its salt rejection characteristics is sustained. In addition, the MWCNT/PSf support layer has better mechanical stability than the PSf support layer, there resulting in an increased resistance of flux reduction due to physical pressure.

This study was aimed to examine inorganic fouling and fouling reduction method in direct contact membrane distillation(DCMD) process. Synthetic seawater of NaCl solution with CaCO3 and CaSO4 was used for this purpose. It was found in this study that both CaCO3 and CaSO4 precipitates formed at the membrane surface. More fouling was observed with CaSO4(anhydrite) and CaSO4･0.5H2O(bassanite) than CaSO4･2H2O(gypsum). CaCO3 and gypsum were detected at the membrane surface when concentrates of SWRO(seawater reverse osmosis) were treated by the DCMD process, while gypsum was found with MED(multi effect distillation) concentrates. Air backwash(inside to out) was found more effective in fouling reduction than air scouring.

A-KRS는 한국원자력연구원에서 개발한 파이로프로세싱 처리된 폐기물을 처분하는 개념이다. 고준위 방사성폐기물은 파이로프로세싱에 의하여 최소화되며, 최종 발생된 고준위 방사성폐기물은 모나자이트 세라믹 폐기물 형태로 제조된다. 모나자이트 세라믹 폐기물은 처분공에 영구 처분되어 열을 발생시킨다. 발생된 열은 폐기물을 보호하는 캐니스터 및 완충재의 온도를 상승시켜 설계 기준을 초과 시킬 수 있다. 온도는 처분공 간의 거리로 조절 가능하며 한국원자력연구원에서 해석한 바 있다. 한국원자력연구원에서 해석한 경계조건은 완벽 접촉을 가정한 것이기 때문에, 최초 처분 시에 발생하는 간격에 의해 발생하는 열 저항에 의한 온도 분포는 알 수 없다. 이를 보완하기 위하여, 본 논문에서는 최초 처분 시 존재하는 간격에 의한 열 전달 해석을 수행하였다. 또한 발열체와 캐니스터 간의 공극을 추가하여 온도 분포 해석을 수행하였다. COMSOL 전산해석 소프트웨어를 이용하여 열전달 해석을 수행하였다.

In Korea, species of the genus Ptecticus Loew, 1855 (Family Stratiomyidae) have been known as three species, P. aurifer (Walker, 1854), P. matsumurae Lindner, 1936 and P. japonicus (Thunberg, 1789) (= P. tenebrifer (Walker, 1849)). Additionally, an unrecorded species, P. sinchangensis Ôuchi, 1938, is founded in South Korea. We therefore report the species for the first time in Korea with morphological diagnoses and key for the identification of species of the genus. In total, the members of the genus Ptecticus are officially recognized as four species in Korea.

Interconnected meso/microporous activated carbons were prepared from pumpkin seeds using a simple chemical activation method. The porous carbon materials were prepared at different temperatures (PS-600, PS-700, PS-800, and PS-900) and demonstrated huge surface areas (645–2029 m2 g–1) with excellent pore volumes (0.27–1.30 cm3 g–1). The wellcondensed graphitic structure of the prepared activated carbon materials was confirmed by Raman and X-ray diffraction analyses. The presence of heteroatoms (O and N) in the carbon materials was confirmed by X-ray photoemission spectroscopy. High resolution transmission electron microscopic images and selected area diffraction patters further revealed the porous structure and amorphous nature of the prepared electrode materials. The resultant porous carbons (PS-600, PS-700, PS-800, and PS-900) were utilized as electrode material for supercapacitors. To our delight, the PS-900 demonstrated a maximum specific capacitance (Cs) of 303 F g–1 in 1.0 M H2SO4 at a scan rate of 5 mV. The electrochemical impedance spectra confirmed the poor electrical resistance of the electrode materials. Moreover, the stability of the PS-900 was found to be excellent (no significant change in the Cs even after 6000 cycles).

Although Agaricus bisporus mushroom is a popular mushroom consumed world-widely, the application of common bio-elements to verify its geographical origin remains highly limited. Therefore, this study aimed to verify whether the six cultivation regions in Korea of A. bisporus could be determined by the stable isotope composition analysis of bio-elements, which are unique and abundant in most living creatures. δ13C, δ15N, δ18O, and δ34S in A. bisporus were influenced by the region, cultivar, and the interactions between these two factors (P < 0.05). In particular, the effect of cultivation region was more significant to the isotope ratio profiles as compared to the mushroom cultivar effect. During the cultivation period of A. bisporus, the C, N, O, and S isotopic fractionation was observed between the mushroom and cultivation medium, note higher in the mushroom (P < 0.05). Two dimensional plot of δ15N, δ18O, or δ34S effectively distinguished the cultivation regions, Nonsan, Buyeo, Boryung, Daegu, and/or Gyeongju examined in this study. Further, these isotope ratio profiles measured in this study would be statistically analyzed with various chemometrics to provide isotope markers for the authenticity of geographical origin. Our preliminary case study improves our understanding of how the isotope composition of A. bisporus varies with respect to cultivation regions and cultivars. In conclusion, the analysis of stable isotope ratios is a suitable potential tool for discrimination between the cultivation origins of A. bisporus collected from Korea, with potential application to other countries after certain validation steps required.

Seawater desalination market after global economic crisis has been stalled due to the market uncertainties and decreased demand in desalination. It is important to review the status of the market and to estimate the appropriate share of Forward osmosis-Reverse Osmosis (FO-RO) hybrid desalination technology by figuring out the outlook of the desalination market. Main part of the desalination market will still be MENA (Middle East and North Africa) in the near future due to the fast population increase and high dependency of fossil fuel in the region. The market for FO-RO hybrid technology, however, might be smaller than the conventional SWRO desalination market anyway because of aesthetic issues from using wastewater as raw water and higher costs associated with capex. Therefore, it is essential to improve FO membrane performance and system operation technologies in order to make the hybrid technology attractive compared to the conventional SWRO technology.

The main objective of this paper is to develop computer simulation program for performance evaluation and cost estimation of a reverse osmosis (RO) and pressure-retarded osmosis (PRO) hybrid process to propose guidelines for its economic competitiveness use in the field. A solution-diffusion model modified with film theory and a simple cost model was applied to the simulation program. Using the simulation program, the effects of various factors, including the Operating conditions, membrane properties, and cost parameters on the RO and RO-PRO hybrid process performance and cost were examined. The simulation results showed that the RO-PRO hybrid process can be economically competitive with the RO process when electricity cost is more than 0.2 $/kWh, the PRO membrane cost is same as RO membrane cost, the power density is more than 8 W/m2 and PRO recovery is same as 1/(1-RO recovery).

23 완전요인배치법에 의해 설계된 반응조건에 따라 컨벡 션오븐을 반응기로 하여 제조된 starch citrate들의 반응성( 반응효율, 몰치환도), 저항전분 함량 및 페이스팅 점도 특 성을 조사하고, 분석된 특성치들을 이용한 요인분산분석을 통해 주요인들(전분종류, pH, 반응온도) 및 이들의 상호작 용들이 starch citrate의 특성에 미치는 영향을 조사하였다. 아밀로오스 함량(전분종류)의 증가는 반응효율, 저항전분 함량을 증가시켰으며 페이스팅 점도 특성치들을 감소시키 는 효과를 나타내었다. pH의 증가는 반응효율, 몰치환도, 저항전분 함량을 감소시켰으나 반응온도는 반대의 경향을 나타내었다. 페이스팅 점도 특성에 있어 pH의 증가는 페이 스팅 온도, 최고점도, 최저점도, 최종점도 등을 증가시켰으 나 반응온도의 증가는 감소시키는 효과를 나타내었다. 한 편 주요인들의 상호작용에 있어 전분종류-pH와 pH-반응온 도는 반응효율, 몰치환도 및 저항전분 함량에 정도의 차이 는 있지만 유의적인 영향을 미쳤으나 전분종류-반응온도의 상호작용은 이들 특성치들에 대한 유의적인 효과를 나타내 지 않았다. 페이스팅 점도 특성들에 대해 전분종류-pH, 전 분종류-반응온도 및 pH-반응온도의 상호작용들은 유의적인 효과를 나타내었으며, 특히 전분종류-pH와 전분종류-반응 온도의 상호작용들은 페이스팅 점도 특성치들의 감소를 초 래하였다. 결과적으로 생전분의 건조중량 대비 10%의 구 연산, 3시간의 반응시간과 본 연구에서 채택된 반응조건들 의 범위 내에서 생전분의 아밀로오스 함량이 높을수록, pH 는 낮을수록, 반응온도는 높을수록 starch citrate의 저항전 분 함량이 증가하며, 생전분의 아밀로오스 함량이 낮을수 록, pH가 높을수록, 반응온도가 높을수록 페이스팅 점도와 같은 물리적 기능성이 향상된 starch citrate를 얻을 수 있 을 것으로 판단된다.