• 한국환경농학회지
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• 제40권2호
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• pp.92-98
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• 2021

BACKGROUND: Unintentional residual pesticide in soil derived from preceding crops and the transfer to succeeding crops was considered a critical barrier for positive list system (PLS). Thus, an uncertain risk is predicted for ethoprophos applied at cultivation of preceding crop (Korean cabbage) to succeeding crop (spinach). METHODS AND RESULTS: Ethoprophos was treated on soil following the recommended dose and 5 times dose according to the safe use guidelines for Korean cabbage after seeding. On the 4 days after harvesting of preceding crop, spinach was sowed. The initial residual amounts of ethoprophos on soil (7.081-19.493 mg/kg) were decreased to 3.832-7.218 mg/kg until the harvest of Korean cabbage, and then finally decreased to 0.011-0.079 mg/kg after spinach cultivation. The uptake rates of ethoprophos from soil by Korean cabbage were 0.01-0.03% and distributed to root (0.150-0.903 mg/kg) and shoot (0.021-0.151 mg/kg), respectively. The residual amounts of uptake and translocation from preceding crop cultivated soil to spinach edible part were found to be below LOQ. CONCLUSION: The plant back internal (PBI) for ethoprophos is not recommended during sequential cultivation of leafy vegetables, since the residual amounts of ethoprophos in spinach were less than MRL (0.02 mg/kg).

• 디지털융복합연구
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• 제17권2호
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• pp.31-36
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• 2019

최근 세계경제는 4차 산업혁명이라는 시대의 흐름에 따라 서로 다른 기술 산업 간 융 복합이 활성화되고 새로운 기술이 빠르게 창출되고 있다. 우리나라도 4차 산업혁명에 대응하고 글로벌 경쟁력을 확보하기 위하여 신기술 신서비스 기반의 혁신기술을 육성하고 있으나, 각종 규제로 인하여 신기술 신서비스에 대한 진입이 어려운 실정이다. 이에 정부는 신기술 신서비스를 활용한 혁신사업이 규제의 제약 없이 실험 실증하고 사업화 할 수 있도록 규제샌드박스(Sandbox)가 적용되는 규제자유특구도입을 추진하고 있다.. 본 연구는 지역특화발전특구와 새로이 도입되는 규제자유특구를 비교 연구함으로써, 전국에 획일적으로 적용되는 규제만을 완화하는 지역특화발전특구의 한계를 고찰하고, 규제자유특구가 신기술 기반의 실증 테스트 베드로 육성할 방향과 지역의 혁신성장 거점으로 성장할 방안을 제시하고자 한다.

• 대한의생명과학회지
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• 제24권4호
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• pp.357-364
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• 2018

Manganese (Mn) is used as main materials in various chemical processes of industry, but it suggested that Mn brings about its toxicant by fume or dust through respiratory system and skin barrier. Mn toxicant induces the loss of mental health and life quality by cerebrovascular and skin diseases. Nevertheless, it lefts much unknown on the mechanism and the effectively therapeutic methods about Mn toxicant. Therefore, this study was evaluated the cytotoxicity induced by manganese dioxide ($MnO_2$) in cultured NIH3T3 fibroblasts, and also, the correlation between $MnO_2$-induced cytotoxicity and oxidative stress was examined. While, the effect of Eclipta prostrata L. (EP) extract belong to Compositae was assessed against $MnO_2$-induced cytotoxicity in the view of antioxidative effect for searching the natural resources mitigating or preventing the $MnO_2$-induced cytotoxicity. In this study, $MnO_2$-induced cytotoxicity was revealed as mid-toxic by Borenfreud and Puerner's toxic criteria, and catalase (CAT), an antioxidant prevented $MnO_2$-induced cytotoxicity by the remarkable increase of cell viability in these cultures. While, in the protective effect of EP extract on $MnO_2$-induced cytotoxicity, EP extract effectively prevented the cytotoxicity induced by $MnO_2$ via antioxidative effects such as xanthine oxidase (XO) inhibitory ability and DPPH-radical scavenging ability. From the above results, EP extract showed the effective prevention against $MnO_2$-induced cytotoxicity correlated with oxidative stress by antioxidative effects. Conclusively, this study may be useful to research or development the alternatively therapeutic agent from natural resources like EP extract for the treatment of diseases resulted in oxidative stress.

• 한국콘텐츠학회논문지
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• 제19권6호
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• pp.655-662
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• 2019

본 연구는 현상학적 해석학을 바탕으로 저소득 조손가정의 조모와의 심층면담을 통해 조모의 양육의 어려움과 양육스트레스에 대해 이해하고자 질적 연구를 수행하였다. 연구결과 저소득 조손가정 조모의 양육스트레스 경험은 경제적 어려움, 노후의 걸림돌이 된 손자녀, 양육의 막막함으로 나타났다. 이러한 연구결과를 토대로 새롭게 부각되고 있는 조손가정 조모의 양육스트레스를 경감시키고 삶의 질을 향상시키기 위한 사회복지개입 방향과 역할을 구체화할 수 있는 근거를 제공하는데 그 의의가 있다. 연구결과를 바탕으로 몇 가지 제언을 한다면 첫째, 현재 시행 중인 지원사업을 재검토하여 지원내용을 확대할 필요가 있다. 둘째, 저소득 조손가정 조모의 양육스트레스와 우울감을 감소시키기 위해 지지프로그램의 개발과 사회적 지원이 필요하다. 조모의 양육에 도움이 될 수 있는 교육 문화와 더불어 멘토링 프로그램을 만들어 부족한 원조관계망을 보완하는 지원도 함께 고려되어야 할 것이다.

• 전기전자학회논문지
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• 제23권3호
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• pp.1108-1111
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• 2019

본 논문은 LLC 공진 컨버터에 적합한 자동화 권선 변압기 설계에 대한 포괄적인 방법에 대해서 나타낸다. 기존의 LLC 공진 변압기는 하나의 보빈에 모든 권선이 감겨져 있기 때문에 자동화 권선 구현이 어렵다는 문제점이 있다. 따라서 본 논문에서는 절연 테이프와 배리어 테이프가 없이 다중 보빈으로 자동 권선이 가능한 LLC 공진 변압기를 제안하였으며 제안한 LLC 공진 변압기의 설계 절차에 대해서도 나타내었다. Maxwell 3D 시뮬레이션 툴을 이용하여 제안한 LLC 공진 변압기의 해석 및 모델링을 상세하게 기술되었으며 또한 3D 모델링에 의해 제작된 제안한 LLC 공진 변압기를 이용하여 프로타입 150W LLC 공진 컨버터를 실험을 통해 확인하였다.

• 한국프랜차이즈경영연구
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• 제11권1호
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• pp.7-17
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• 2020

Purpose - As the competition in the foodservice franchise industry and the market becomes fierce and the entry barrier is lowered, the foodservice franchisor and franchisees strive to increase their competitive advantage in the market. Therefore, the franchisor and franchisees use experience management strategies to enhance the positive experiences of customers visiting the stores. In this regard, this study examines the effects of customer-oriented activities (physical-, social-, health-, and service-oriented activities) on utilitarian and hedonic values, and loyalty using stimulus-organism-response (S-O-R) model and value-expectancy theory. Research design, data, methodology - The data were collected from panels of online survey company, who visited a foodservice franchisee within last month. The survey was conducted for about 15 days from March 7, 2019 to March 21, 2019, and about 3,500 e-mails and messages were distributed to ask for the survey. A total 412 responded and completed the questionnaires. Of the 412 completed questionaires, 12 were discarded due to missing and misinformation data and 400 were retained for further data analysis. Results --The results showed that social oriented activities, health oriented activities, and service oriented activities had positive effects on hedonic value, while physical oriented activities did not have a significant effect on hedonic value. Health oriented activities and service oriented activities had positive effects on utilitarian value, while physical oriented activities and social oriented activities had no significant effects on utilitarian value. Hedonic and utilitarian values also have a positive effect on loyalty. Conclusions - First, food service franchises should provide services and menus in consideration of the health of customers. When a customer visits the store, franchisee should provide more health-oriented food or materials and clean and comfortable conditions so as not to threaten the health of the customer. Second, the food service franchise must build a service-oriented system. Foodservice franchisor need to provide continuous service training not only to the franchisees, but also to the employees of the franchisees. Third, franchise should design a store where customers can form social exchanges through providing various information exchange to customers and making the store as a local community center.

• Journal of Radiation Protection and Research
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• 제45권4호
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• pp.163-170
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• 2020

Background: Gut microflora contributes to the nutritional metabolism of the host and to strengthen its immune system. However, if the intestinal barrier function of the living body is destroyed by radiation exposure, the intestinal bacteria harm the health of the host and cause sepsis. Therefore, this study aims to trace short-term radiation-induced changes in the mouse gut microflora-dominant bacterial genus, and analyze the degree of intestinal epithelial damage. Materials and Methods: Mice were irradiated with 0, 2, 4, 8 Gy X-rays, and the gut microflora and intestinal epithelial changes were analyzed 72 hours later. Five representative genera of Actinobacteria, Firmicutes, and Bacteroidetes were analyzed in fecal samples, and the intestine was pathologically analyzed by Hematoxylin-Eosin and Alcian blue staining. In addition, DNA fragmentation was evaluated by the TdT-mediated dUTP nick-end labeling (TUNEL) assay. Results and Discussion: The small intestine showed shortened villi and reduced number of goblet cells upon 8 Gy irradiation. The large intestine epithelium showed no significant morphological changes, but the number of goblet cells were reduced in a radiation dose-dependent manner. Moreover, the small intestinal epithelium of 8 Gy-irradiated mice showed significant DNA damaged, whereas the large intestine epithelium was damaged in a dose-dependent manner. Overall, the large intestine epithelium showed less recovery potential upon radiation exposure than the small intestinal epithelium. Analysis of the intestinal flora revealed fluctuations in lactic acid bacteria excretion after irradiation regardless of the morphological changes of intestinal epithelium. Altogether, it became clear that radiation exposure could cause an immediate change of their excretion. Conclusion: This study revealed changes in the intestinal epithelium and intestinal microbiota that may pave the way for the identification of novel biomarkers of radiation-induced gastrointestinal disorders and develop new therapeutic strategies to treat patients with acute radiation syndrome.

• 한국지구과학회지
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• 제42권6호
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• pp.605-622
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• 2021

Seasonal forecasting has numerous socioeconomic benefits because it can be used for disaster mitigation. Therefore, it is necessary to diagnose and improve the seasonal forecast model. Moreover, the model performance is partly related to the ocean model. This study evaluated the hindcast performance in the upper ocean of the Global Seasonal Forecasting System version 5-Global Couple Configuration 2 (GloSea5-GC2) using a multivariable integrated evaluation method. The normalized potential temperature, salinity, zonal and meridional currents, and sea surface height anomalies were evaluated. Model performance was affected by the target month and was found to be better in the Pacific than in the Atlantic. An increase in lead time led to a decrease in overall model performance, along with decreases in interannual variability, pattern similarity, and root mean square vector deviation. Improving the performance for ocean currents is a more critical than enhancing the performance for other evaluated variables. The tropical Pacific showed the best accuracy in the surface layer, but a spring predictability barrier was present. At the depth of 301 m, the north Pacific and tropical Atlantic exhibited the best and worst accuracies, respectively. These findings provide fundamental evidence for the ocean forecasting performance of GloSea5.

• Journal of Forest and Environmental Science
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• 제38권2호
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• pp.128-132
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• 2022

Wild boars (Sus scrofa) not only cause crop damage and human casualties, but also facilitate the spread of many infectious diseases in domestic animals and humans. To determine the efficiency of a fencing system in blocking the movement of wild boars, long-term monitoring was performed in a fenced area in Bukhansan National Park using camera traps. Upon monitoring for a period of 46 months, there was a 72.6% reduction in the number of wild boar appearances in the fence-enclosed area, compared to that in the unenclosed area. For 20 months after the fence installation, the blocking effect of the fence was effective enough to reduce the appearance of wild boars by 92.6% in the fence-enclosed area, compared to that in the unenclosed area. The blocking effect of the fence remained effective for 20 months after its installation, after which its effectiveness decreased. Maintaining a fence for a long time is likely to lead to habitat fragmentation. It can also block the movement of other wild animals, including the endangered species - the long-tailed goral. This study suggests a 20-month retention period for the fences installed to inhibit the movement of wild boars in wide forests such as Gangwon-do in South Korea. To identify how long the blocking effect of the fences lasts, further studies are needed focusing on the length and height of the fence, and the conditions of the ground surface.

• Journal of Korea Trade
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• 제24권6호
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• pp.115-134
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• 2020

Purpose - International trade leads to the international division of labor, improving the efficiency of the global economic system. Transport costs are a more serious barrier to international trade than customs tariffs. An increase in competition in the transport sector may thus lead to a reduction in transport costs. However, if a carrier's nationality significantly influences transport costs, simply adding more competing carriers of different nationalities would be ineffective. Therefore, it is necessary to establish national or regional carriers to influence competition and reduce transport costs. This study investigates this "nationality effect" by treating Hanjin Shipping's collapse as a natural experiment. Design/methodology - The theoretical basis of this study is the 3rd-degree price discrimination in container shipping market. By using the monthly data of container freight rates of Korea, China and Japan, this study shows the so-called Korea Premiums, which are the empirical counterparts of nationality effect in Korea container shipping market. For this empirical investigation, the structural model with state-space form is used and the dummy models are also estimated. In addition, because China has been also affected by the Hanjin's collapse, the China premiums are considered too. Findings - Compared with Japan's case, it is shown that there had been the so-called Korea premiums since the collapse of Hanjin Shipping. These results are robust from both the state-space model and dummy models. The time pattern of Korea premiums was consistent with the market evolution, especially the pattern of substitutability in container shipping markets. In addition, this paper shows the magnitude of Korea premiums. Originality/value - The argument of this study that the nationality effect can be interpreted as an extended concept of the home market effect is original, which is expected to evoke future research efforts. Further, the discussion on the shipping industrial policy from both horizontal and vertical aspects will provide the relevant policy makers with solid information, especially for the policy coordination in a global scale.