The levels of Indoor radon can increase in newly built apartments that mainly use construction materials such as concrete. However, radon measurement in newly built buildings has only been implemented recently, and there is a lack of sufficient data for radon management purposes. This study aimed to determine the levels of indoor radon in newly built apartments by regions, sizes of household, and floor (lower, middle, upper floor), and to explore the trend of radon reduction by time according to ventilation methods. Indoor radon was measured in 48 households in four regions (Gyeonggi-do and Gangwon-do). Measurements were performed for 48 hours and 24 hours under closed and ventilated conditions using real-time measurement devices FRD400 and RAD7, respectively. To analyze changes in radon concentration by floors, data were collected by dividing households into lower, middle, and upper floors according to their vertical height. The concentrations of indoor radon ranged from 12.1 Bq/m3 to 559.0 Bq/m3 when windows were closed and 12.0 Bq/m3~500.0 Bq/m3 when ventilated (including both mechanical and natural ventilation). On average, the concentration of closed conditions of household when sealed (arithmetic average 185.3 Bq/m3) was 1.5 times higher than the concentration during ventilation (including mechanical and natural ventilation: 123.8 Bq/m3), and around three times higher than the average for mechanical ventilation (65.7 Bq/m3). It was found that the indoor radon concentration statistically increased as the height increased and the size of the house became smaller. Typically, it took 7 to 8 hours to exceed the standard of 148 Bq/m3 after windows were closed. It decreased to less than 148 Bq/m3 within 3 to 4 hours after operating the mechanical ventilation system. However, in the case of natural ventilation, it takes more than 24 hours to reach below the standard value, and the concentrations stagnated after 24 hours. In conclusion, radon concentration in narrow spaces can be relatively high if ventilation is not sufficient due to the nature of apartments with wall-type structures. Therefore, it is necessary to prepare various radon reduction measures according to floor, size, and ventilation methods.

As global warming and consumer’s preference for tropical/subtropical fruits increase, the number of orchards cultivating tropical/subtropical fruits in Korea is increasing. Accordingly, concerns about the introduction of exotic invasive pests that host tropical fruits. In this study, efficacy of ethyl formate(EF), as alternative to methyl bromide(MB), was evaluated. Commercial trial of EF was conducted in mango post-harvest storage conditions for controlling Scirtothrips dorsalis. Application of 10 g/m3 of EF for 4 hours at 10 ℃ showed proven efficacy on S. dorsalis without any phytotoxic damage on mango fruits in that condition.

The formation of CaCO3 in microalgal culture is investigated and applied for effective separation of microalgae. The presence of several cationic ions in the culture medium mediates the formation of 3 types of mineral precipitates depending on the concentration of mineral precursors, Ca2+ and CO3 2−, amorphous nano-flakes, rhombohedral calcites, and spherical vaterites. While amorphous phased precipitates are formed for all concentrations of mineral precursor, only calcites are formed for 30 mM solutions of mineral precursor, and mixtures of calcites and vaterites are formed for 50 and 100 mM solutions of mineral precursor. The harvesting efficiency is also dependent on the concentration of the mineral precursor: from 90 % for 10 mM to 99 % for 100 mM after 60 mins’ of gravitational sedimentation. The formation of nano-flakes on the surface of microalgal cells induces the flocculation of microalgae by breaking the stable dispersion. The negatively charged surface of the microalgal cell is compatible not only with nano-flake attachment but also with the growth of calcitic crystals in which microalgal cells are embedded.

The electrocaloric effect can be observed in pyroelectric materials based on conversion between electrical and thermal energy, and can be utilized for the future environment-friendly refrigeration technology. Especially, a strong electrocaloric effect is expected in materials in which field-induced phase transition can be achieved. Emerging fluoritestructure ferroelectrics such as doped hafnia and zirconia, first discovered in 2011, are considered the most promising materials for next-generation semiconductor devices. Besides application of fluorite-structure ferroelectrics for semiconductor devices based on their scalability and CMOS-compatibility, field-induced phase transition has been suggested as another interesting phenomenon for various energy-related applications such as solid-state cooling with electrocaloric effect as well as energy conversion/storage and IR/piezoelectric sensors. Especially, their giant electrocaloric effect is considered promising for solid-state-cooling. However, the electrocaloric effect of fluorite-structure oxides based on field-induced phase transition has not been reviewed to date. In this review, therefore, the electrocaloric effect accompanied by field-induced phase transition in fluorite-structure ferroelectrics is comprehensively reviewed from fundamentals to potential applications.

ICT 기반의 해충 이미지 전송 시스템은 담배거세미나방과 파밤나방을 예찰하고 방제하는데 필요한 효과적인 유인 해충 전송수단이다. 시설 온실내 담배거세미나방과 파밤나방을 유인하기 위하여 스마트 트랩을 이용하였다. 스마트트랩은 나방류 해충유인을 위해 성페로몬 4종 장착하였으며 유인된 해충은 특수 카메라를 이용하여 이미지 촬영이 가능하였다. 또한, 해충유인 발광트랩 처리구는 황색광을 사용한 발광 트랩을 사용하였다. 또한 대조구로 기존에 널리 사용되는 델타트랩은 한 종류의 성페로몬을 장착하여 유인력 검정에 이용하였다. 성페로몬 한 종류만 사용한 델타트랩 처리는 담배거세미나방 페로몬 루어를 사용하였고, 4종류의 성페로몬을 설치한 스마트 트랩 처리구는 담배거세미나방, 뒷날개흰나방, 파밤나방, 왕담배나방용 성페로몬 루어를 사용하였다. 실험은 2018년 6월 1일부터 8월 31일까지 함안 시설원예연구소의 13m2의 소형비닐하우스에서 수행하였으며 공시작물은 파프리카 ‘시로코’ 품종과 토마토 ‘데프니스’ 품종을 사용하였다. 나방류 해충의 유인력 검정결과 파프리카와 토마토를 식재한 온실 모두 성페로몬 루어 한 종류를 설치한 델타트랩보다 유인발광 트랩 처리구에서 높은 나방류 유인율을 나타내었다. 시험기간 유인발광 트랩의 경우 유인 포획된 총 나방수는 파프리카 온실에서 평균 97마리, 토마토 온실에서 75마리가 유인 포획되어 가장 높았다. 그러나, 성페로몬 1종 및 4종을 설치한 델타트랩 및 스마트트랩처리구는 두 개의 온실 모두 평균 5마리 이하의 유인율을 나타내었다. 따라서, 시설내 나방류 예찰 및 유인 방제하기 위해서는 기존 성페로몬만 사용하기 보다는 유인발광 트랩을 함께 설치하는 것이 나방류 유인포획에 효과적이라고 판단되었다.

Riptortus pedestris is a major agricultural pest in Korea. To manage this pest, it is necessary to understand the complete life history of R. pedestris. However, most studies have focused on the summer period when the pest attacks crops. Therefore, we conducted laboratory and field experiment to identify overwintering behavior of adult R. pedestris. First, we conducted two laboratory experiments to examine overwintering habitat preferences and spatial distribution of R. pedestris in the habitat. Second, we conducted field survey to characterize overwintering sites of R. pedestris in diverse landscapes. In the laboratory conditions, R. pedestris almost exclusively showed overwintering behavior in the leaf litter arena (63%) among the structures tested (rocks: 3%; rotten wood: 0%). And spatial distribution of R. pedestris showed solitary behavior in leaf litters. In the field, we located 12 individuals of overwintering adults from the urban areas, whereas no individuals were found from the high-elevation mountains and agricultural landscapes. Our results suggest that R. pedestris mainly use leaf litter as an overwintering structure, with solitary behavior, and low-elevation forested areas near urban landscapes seem to be more preferred overwintering sites.

Cordycepin (3’-deoxyadenosin), a polyadenylation specific inhibitor, is the main functional component in Cordyceps militaris which is one of the top three famous traditional Chinese medicine. It has been shown to possess many pharmacological activities including immunologically stimulating, anti-cancer, anti-bacterial, and anti-virus, anti-infection effects. However, its anti-cancer molecular mechanisms are poorly understood. In this study, the apoptotic effects by cordycepin were investigates in human leukemia cells. Treatment of cordycepin significantly inhibited cells growth in a concentrationdependent manner by inducing apoptosis, as evidenced by morphological change and apoptotic cell death such as formation of apoptotic bodies, DNA fragmentation and increased populations of sub-G1. Induction of apoptosis by cordycepin was associated with modulation of Bcl-2 and inhibitor of apoptosis proteins (IAP) family expression. Cordycepin also increased reactive oxygen species (ROS) generation, activation of casepase-3, caspase-8, caspase-9, cleavage of poly(ADP-ribose) polymerase (PARP), β-catenin and phospholipase C (PLC)-γ1 protein. The quenching of ROS generation by N-acetyl-L-cysteine administration, a scavenger of ROS, reversed the cordycepin-induced apoptosis effects. Theresults suggested that cordycepin may be a potential chemotherapeutic agent for the treatment of leukemia patients [This work was supported by Blue-Bio Industry RIC at Dong-Eui University as a RIC (08-06-07) program of ITEP under Ministry of Knowledge Economy].

본 논문은 전략적 제휴를 조직간 학습과정으로 규정하고, 각각의 제휴 파트너들이 전략적 제휴를 통해 어떤 학습 유형을 추구하느냐에 따라 조직간 지식 이전의 속도가 차이난다고 설정하였다. 제휴 파트너들의 조직학습 유형(지식 탐색과 지식 활용)이 서로 다를 경우는 여타 경우에 비해 상대적으로 지식이전의 속도가 빠를 것이며, 제휴 파트너들의 조직학습 유형이 모두 지식 활용인 경우는 다른 경우에 비해 상대적으로 지식이전의 속도가 늦을 것이다. 본 논문은 생수 산업에서 다국적 기업과 현지기업간의 합작투자 사례분석을 통해 이 같은 명제들을 살펴보았다. 사례 분석 결과 상호 보완적인 지식 기반은 학습 제휴의 강력한 동기가 될 수 있지만, 아울러 성공 체험을 바탕으로 축적된 지식은 조직간 학습에 걸림돌이 될 수도 있었다.

최근 국제경쟁력에 대한 연구와 토론이 매우 활발함에도 불구하고 아직까지 국제경쟁력과 관련된 각종 논의들이 체계화되지 못하고 있다. 본 연구에서는 무역이론, 해외직접투자이론, 글로벌 전략이론, Porter(1990)의 Diamond 모델 등 기존의 국제경쟁력 연구를 패러다임 차원에서 분석하였다. 기존 연구들은 국제경쟁력을 창출하는 주체(subject), 연구의 분석단위(unit of analysis), 국제경쟁력의 원천(sources)과 결과(outcomes) 개념들을 혼동하고 있거나 본국 (home base)과 다국적 기업의 역할에 대해 서로 다른 가정을 하고 있었다. 앞으로의 국제경쟁력 연구는 개발 기업이나 산업이 아닌 산업 군집(cluster)을 연구대상으로 하여 그동안 각기 별도로 논의되었던 기업, 산업, 국가 차원의 경쟁력 요인을 통합하는 노력을 기울여야 할 것이다. 이때 통합 모델의 이론적 근거로 제도론적 접근법을 들 수 있다. 제도론적 접근법에서는 기업의 행동이 영향을 미치는 특정 국가에 내재하는 제도들간의 관계(arrangements) 혹은 연결 메카니즘(mechanism)에서 국제경쟁력의 원천을 탐구하는 것이다. 다만, 한가지 주의할 점은 국가간경쟁력 모델을 기업에 적용시키거나 기업경쟁력 모델을 국가 차원으로 확장시켜 통합 모델을 만들어서는 안된다는 것이다.