• Korean Journal of Ichthyology
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• v.35 no.1
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• pp.50-56
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• 2023

This study is the first to report the biometric information between the length and weight relationships (LWR) and seasonal body condition factors (K) of Sebastes zonatus Chen & Barsukov, 1976 and Thamnaconus modestus (Günther, 1877) inhabiting the waters off Ulleung-do and Dokdo. The LWRs in spring and summer, and all seasons combined were highly correlated (r²>0.959), and the regression slopes of LWRs were significantly different between the spring and summer in both species. The body conditions of the two fish were significantly higher during the spring than during the summer, reflecting their fatness in relation to spawning. The results from this study contribute to the understanding of the biology of S. zonatus and T. modestus and provide useful data for the development of conservation and management plans for these species.

• Journal of Practical Agriculture & Fisheries Research
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• v.17 no.1
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• pp.163-179
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• 2015

The aim of this study is to investigate to which degree farmers did the crop switching and cultivar renewal as a confrontational strategy to climate change, and which problems they had in that process, and then to provide the supporting plans for them. We conducted a questionnaire survey of 15 citrus farmers of the KNCAP graduates in Jeju Island. Most of the survey respondents agreed to the climate change of Jeju Island and the subtropical climate of its coastal area. The farmers have experienced irregular weather such as abnormal high temperature, frequent rain, and droughts, resulting in the harmful insects and new weeds attack. As the climate change strategies, they are adopting a greenhouse culture system, improving a soil drainage using reorganization of planting space, making a new pest management program, and trying to switch a crop to subtropical fruits. It is expected that 50% of the survey respondents have changed their crops or will do; and 73 % of them have changed cultivar or have a plan to do. Only a few farmers directly pointed to a reason for their efforts to change the crops or to renew the cultivars as the anti-climate change strategy, however, most farmers answered the reason was to increase profitability by meeting their consumers' tastes. Presently, it is not the anti-climate change strategy but increase of profitability by meeting the consumers' needs the reason why most of the survey respondents have changed their crops or renewed the cultivars, while a few of them switched their crops to a subtropical fruit trees due to climate change. On the crop switching, they had some difficulties such as a labor shortage, availability of land, operating costs and instable income. On the cultivar renewal, also, they encountered the lack of cultivating techniques for new cultivars and the dim future for the new market. In long-term perspective, Jeju's farmers need new information and educational programs about the effect of climate change on agriculture of Jeju, and cultivation techniques for new crops and new cultivars.

• Journal of The Geomorphological Association of Korea
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• v.27 no.1
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• pp.61-89
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• 2020

The objective of this study is to characterize landslide susceptibility depending on various geo-environmental variables as well as to compare the Frequency Ratio (FR) and Evidential Belief Function (EBF) methods for landslide susceptibility analysis of rainfall-induced landslides. In 2013, a total of 259 landslides occurred in Chuncheon, Gangwon Province, South Korea, due to heavy rainfall events with a total cumulative rainfall of 296~721mm in 106~231 hours duration. Landslides data were mapped with better accuracy using the geographic information system (ArcGIS 10.6 version) based on the historic landslide records in Chuncheon from the National Disaster Management System (NDMS), the 2013 landslide investigation report, orthographic images, and aerial photographs. Then the landslides were randomly split into a testing dataset (70%; 181 landslides) and validation dataset (30%; 78 landslides). First, geo-environmental variables were analyzed by using FR and EBF functions for the full data. The most significant factors related to landslides were altitude (100~200m), slope (15~25°), concave plan curvature, high SPI, young timber age, loose timber density, small timber diameter, artificial forests, coniferous forests, soil depth (50~100cm), very well-drained area, sandy loam soil and so on. Second, the landslide susceptibility index was calculated by using selected geo-environmental variables. The model fit and prediction performance were evaluated using the Receiver Operating Characteristic (ROC) curve and the Area Under Curve (AUC) methods. The AUC values of both model fit and prediction performance were 80.5% and 76.3% for FR and 76.6% and 74.9% for EBF respectively. However, the landslide susceptibility index, with classes of 'very high' and 'high', was detected by 73.1% of landslides in the EBF model rather than the FR model (66.7%). Therefore, the EBF can be a promising method for spatial prediction of landslide occurrence, while the FR is still a powerful method for the landslide susceptibility mapping.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2020.08a
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• pp.69-69
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• 2020

식물체가 건조 스트레스를 받으면 각 기관 물질 생산의 변이, 분화 및 발달 억제를 통해서 식물의 생산활동을 현저히 저하시켜, 식물의 생장, 형태, 개체발생 및 대사생리에 영향을 미치는 것으로 연구되어 왔다. 최근 기후 온난화로 인해 온도가 점진적으로 상승하고 가뭄과 같은 이상기상이 빈번하게 발생함에 따라 많은 노지 작물의 농업 생산성이 약화되고 있다. 배추는 우리나라의 대표적인 식품 중 하나인 김치의 주재료로 연중 안정적인 생산과 공급이 필요시 되지만, 배추의 경우 건조 조건에서 엽육조직의 붕괴와 같은 생리장해가 발생되기 때문에 최근 발생되고 있는 이상 기후의 영향으로 안정적인 생산이 어려워지고 있는 실정이다. 하지만, 배추에서는 이상 기후에 대응이 가능한 내건성 품종의 육성을 위한 연구는 미흡한 실정이다. 따라서 본 연구에서는 내건성이 높은 배추 개발을 위한 기초소재를 찾는 것을 목적으로 농촌진흥청 유전자원센터에서 보존하고 있는 재래종 배추 30계통을 분양받아 강릉원주대학교 생명과학대학 내의 조직배양실을 이용하여 연구를 수행하였다. 배지는 Tissue Culture Square Dish(125×125×20mm)에 Agar를 녹여 40ml씩 분주하여 고체배지를 조성한 후, 건조 처리구 Polyrthylene glycol 6000(PEG) 0%(Control), 20%(Mild Stress), 30%(Severe Stress)를 설정하여 60ml씩 추가 분주하여 배양기 28℃에서 15시간 처리를 하였다. 분양받은 각 계통의 종자는 1% 차아염소산 나트륨으로 10분간 종자표면을 살균한 후, 5번 정도 멸균수로 헹군 후, 표면 살균한 재래종 종자를 고체배지 시험관에 6립씩 치상하였다. 식물체 생육은 각 처리구별 3반복으로 하였으며 주간 12시간 주기, 광도 2,400Lux, 온도 20℃의 조직배양실에서 치상 후 7일간 생육하였다. 치상 후 7일간 생육시킨 식물체를 채취하여 지상부생체중, 지하부 생체중, 뿌리 길이를 측정하였으며, 지상부와 지하부로 나누어 50℃에서 72시간 건조시킨 후, 건물 생산량을 조사하였다. 본 실험 결과 건조 처리(PEG-6000)는 배추의 생장을 저해하였지만, 생육 저해 정도는 계통간의 차이가 있는 것을 관찰할 수 있었으며 무처리구와 스트레스 처리구간의 생장량 변화 정도를 기반으로 군집분석을 수행한 결과 'IT110483'과 'IT104903' 계통이 실험에 공시된 계통들 중 상대적으로 강한 건조 내성을 가진 것을 확인할 수 있었다. 따라서, 재래종 배추 계통 중 일부는 건조내성이 강한 새로운 배추 품종을 육성하는데 있어 유용하게 이용될 수 있을 것으로 사료된다.

• Korean Journal of Organic Agriculture
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• v.32 no.1
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• pp.107-125
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• 2024

Three types of veterinary antibiotics, including oxytetracycline (OTC) and chlortetracycline (CTC) of tetracycline class and amoxicillin (AMX) of penicilline class, were artificially introduced into the irrigation water. The residue of veterinary antibiotics in the soil, the absorption-translocation of veterinary antibiotics into the red lettuce and young radish plant, and crops yield were investigated according to the agricultural water irrigation method (surface drip irrigation, underground drip irrigation, and sprinkler irrigation). There was no significant difference in the residue and translocation of veterinary antibiotics in the soils and crops according to the irrigation method and type of veterinary antibiotics (p>0.05). For the edible parts of red lettuce and young radish, all three types of veterinary antibiotics were found to be below the detection limit, indicating that the safety of the crops was secured. The translocation factor of red lettuce and young radish were found to be less than 0.3 and 0.2, respectively. However, continuous introduction of veterinary antibiotics in agricultural arable lands may have negative effects by affecting soil microbial activity and soil microbe species diversity, so continuous management is deemed necessary.

• Journal of Sensor Science and Technology
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• v.33 no.1
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• pp.40-47
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• 2024

The creation of vertically aligned one-dimensional (1D) nanostructures through the decoration of n-type tin oxide (SnO₂) on p-type chromium oxide (Cr₂O₃) constitutes an effective strategy for enhancing gas sensing performance. These heterostructures are deposited in multiple stages using a glancing angle deposition technique with an electron beam evaporator, resulting in a reduction in the surface porosity of the nanorods as SnO₂ is incorporated. In comparison to Cr₂O₃ films, the bare Cr₂O₃ nanorods exhibits a response 3.3 times greater to 50 ppm H₂S at 300℃, while the SnO₂-decorated Cr₂O₃ nanorods demonstrate an eleven-fold increase in response. Furthermore, when subjected to various gases (CH₄, H₂S, CO₂, H₂), a notable selectivity toward H₂S is observed. This study paves the way for the development of p-type semiconductor sensors with heightened selectivity and sensitivity towards H₂S, thus advancing the prospects of gas sensor technology.

• Journal of the Korean Society of Radiology
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• v.81 no.6
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• pp.1397-1411
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• 2020

Purpose To survey the perception, knowledge, wishes, and expectations of Korean radiology residents regarding artificial intelligence (AI) in radiology. Materials and Methods From June 4th to 7th, 2019, questionnaires comprising 19 questions related to AI were distributed to 113 radiology residents. Results were analyzed based on factors such as the year of residency and location and number of beds of the hospital. Results A total of 101 (89.4%) residents filled out the questionnaire. Fifty (49.5%) respondents had studied AI harder than the average while 68 (67.3%) had a similar or higher understanding of AI than the average. In addition, the self-evaluation and knowledge level of AI were significantly higher for radiology residents at hospitals located in Seoul and Gyeonggi-do compared to radiology residents at hospitals located in other regions. Furthermore, the self-evaluation and knowledge level of AI were significantly lower in junior residents than in residents in the 4th year of training. Of the 101 respondents, only 16 (15.8%) had experiences in AI-related study while 91 (90%) were willing to participate in AI-related study in the future. Conclusion Organizational efforts through a radiology society would be needed to meet the need of radiology trainees for AI education and to promote the role of radiologists more adequately in the era of medical AI.

• The Journal of Internal Korean Medicine
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• v.45 no.2
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• pp.208-218
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• 2024

We report a case of generalized dystonia that developed from oromandibular dystonia and improved following Korean medicine treatment. The patient was hospitalized for 18 days and treated with herbal medicine, mainly Hyeongbangsabaek-san and Soyangbowi-tang, acupuncture, electroacupuncture, pharmacopuncture, cupping, and moxibustion. To evaluate the clinical effects of the treatment, we used the Unified Dystonia Rating Scale (UDRS) and Global Dystonia Severity Rating Scale (GDS) and checked dyskinesia occurrence in a diary recorded by the patient's guardian. After 18 days of hospitalization, the UDRS for the trunk, upper extremities, and lower face improved by more than 50%, and the GDS for the whole region, except the larynx and lower face, also improved. In addition, the maximum duration of dystonia decreased from 6 hours to 3 hours, and the pain and numbness associated with dystonia disappeared. This case suggests that Korean medicine treatment is effective in treating generalized dystonia.

• Geophysics and Geophysical Exploration
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• v.27 no.1
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• pp.37-50
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• 2024

The magnetotelluric (MT) survey can be affected by external environmental factors. In particular, when acquiring MT data in islands, it is essential to consider the combined effect of topography and sea to understand the results and make accurate interpretations. To analyze the MT response (apparent resistivity, phase) with consideration of the effect of topography and sea, a small cone-shaped island model surrounded by deep sea was created. Two-dimensional (2-D) and three-dimensional (3-D) forward modeling were performed on the terrain model considering topography and the island model considering both topography and sea. The 2-D MT response did not reflect the topographic and sea effect of the direction orthogonal to the 2-D profile. The 3-D MT response included topographic and sea effects in all directions. The XY and YX components of the apparent resistivity were separated on undulating topography, such as a hill. A conductor at 1 km below sea level could be distinguished from topographic and sea effects in the MT response, and low resistivity anomaly was attenuated at greater depths. This study will facilitate understanding of field data measured on small islands.