• 한국농공학회논문집
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• 제65권3호
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• pp.57-67
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• 2023

A flash drought is a rapid-onset drought that develops over a short period of time as weather and environmental factors change rapidly, unlike general droughts, due to meteorological abnormalities. Abnormally high evapotranspiration rates and rapid declines in soil moisture increase vegetation stress. In addition, crop yields may decrease due to flash droughts during crop growth and may damage agricultural and economic ecosystems. In this study, Flash Drought Intensity Index (FDII) based on soil moisture data from Gravity Recovery Climate Experiment (GRACE) was used to analyze flash drought. FDII, which is calculated using soil moisture percentile, is expressed by multiplying two factors: the rate of intensification and the drought severity. FDII was developed for domestic flash drought events from 2014 to 2018. The flash drought that occurred in 2018, Chungcheongbuk-do showed the highest FDII. FDII was higher in heat wave flash drought than in precipitation deficit flash drought. The results of this study show that FDII is reliable flash drought analysis tool and can be applied to quantitatively analyze the characteristics of flash drought in South Korea.

• 동양고전연구
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• 제57호
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• pp.9-40
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• 2014

이 논문은 임진왜란을 전후한 사회적 대혼란에 대한 여헌(旅軒)의 총체적 고민과 그가 제시한 궁극적 해결방안에 관한 연구이다. 여헌은 조선이 왜란 발생 이전에 이미 대혼란을 겪을 수밖에 없는 사회적 국면에 놓여있었다고 반성하였다. 군신상하(君臣上下)가 모두 의리(義理)에 맞는 삶을 살지 못하였고 국가는 도(道)를 실현하는 방식으로 운영되지 못하였다. 그런 상황에서 왜적의 침략은 홍수와 같은 자연적 재해의 일종일 뿐이어서 임진년 이후 닥친 사회적 대혼란의 총체적 책임을 전적으로 왜적에게 돌릴 수는 없다고 보았다. 여헌은 민심이 기아와 질병으로 인해 이반되고 금수(禽獸)처럼 변하고 있는 지경이었는데 조정이 직접적인 기아 구제보다는 성을 수축하고 군사를 조련하느라 백성들을 더욱 나락으로 내모는 상황에 주목하였다. 그가 보기에 대혼란의 근본 원인은 조선의 군신(君臣)과 사민(士民)이 근본적으로 인심(人心)을 상실하였다는 데 있었고, 전쟁과 그 여파로 금수(禽獸)와 같은 짓을 하게 된 것은 그 내면이 표출된 것에 지나지 않았다. 여헌은 "피란록(避亂錄)"에서 왜란의 백성들의 참상을 상세히 묘사하고 국가정책의 난맥상을 치밀히 분석함으로써, 전사회적 반성을 촉구하고 올바른 극복의 길을 제시하고자 하였다. 특히 여헌은 당시 "주역(周易)"연구에 심혈을 기울이고 있었는데, 이는 길흉화복과 치란흥망의 이치를 명확히 이해하는 것이 사회적 대혼란을 근본적으로 해결하는 합당한 방법이라고 여겼기 때문이다. 여헌이 보기에, 인심이 무너진 시대에서는 사람마다 자신의 일상적인 자리에서 리(理)를 지키고 도(道)를 실현해나가려고 노력해 나가는 것이 가장 근본적인 일이었고, 그것이 바로 자신에게 맡겨진 선비의 사명이었다.

• Asian Pacific Journal of Cancer Prevention
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• 제13권11호
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• pp.5887-5895
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• 2012

Background: To determine the effect of essential oil obtained from a traditionally used medicinal plant Tridax procumbens L, on lung metastasis developed by B16F-10 melanoma cells in C57BL/6 mice. Materials and Methods: Parameters studied were toxicity, lung tumor nodule count, histopathological features, tumor directed capillary vessel formation, apoptosis and expression levels of $P^{53}$ and caspase-3 proteins. Results: In vitro the MTT assay showed cytotoxicity was found to be high as 70.2% of cancer cell death within 24hrs for $50{\mu}g$. In vivo oil treatment significantly inhibited tumor nodule formation by 71.7% when compared with untreated mice. Formation of tumor directed new blood vessels was also found to be inhibited to about 39.5%. TUNEL assays also demonstrated a significant increase in the number of apoptotic positive cells after the treatment. $P^{53}$ and caspase-3 expression was also found to be greater in the essential oil treated group than the normal and cancer group. Conclusions: The present investigation showed significant effects of the essential oil of Tridax procumbens L in preventing lung metastasis by B16F-10 cell line in C57BL/6 mice. Its specific preventive effect on tumor directed angiogenesis and inducing effect on apoptosis warrant further studies at the molecular level to validate the significance of Tridax procumbens L for anticancer therapy.

• 대한간호학회지
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• 제42권6호
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• pp.879-888
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• 2012

Purpose: There is evidence that parent-child cohesion is a potentially influential factor in children's self-esteem and acculturation. However, no research to date has examined cohesion with parents as a potential pathway between Korean proficiency and self-esteem or acculturation among children from multicultural families. This study was done to address these limitations by examining whether and to what extent cohesion with parents mediated the effect of Korean proficiency on self-esteem and acculturation among children from multicultural families. Methods: Data were collected from a sample of 138 mothers and their children living in Seoul, Daegu, Kyungi province, and Kyungpook province. Multiple regression analysis was used to examine the relationships between the variables of interest. Mediation effects of cohesion with parents were tested by following the procedure recommended by Baron and Kenny (1986). Results: Cohesion with parents partially mediated the relationship between Korean proficiency and self-esteem. For children's acculturation, the effect of Korean proficiency was partially mediated through father-child cohesion. Mother-child cohesion completely mediated the relationship between Korean proficiency and acculturation. Conclusion: These findings suggest that to help children from multicultural families experiencing difficulties with self-esteem or acculturation, it might be useful to develop programs that are aimed at strengthen cohesion with parents.

• 한국생물정보학회:학술대회논문집
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• 한국생물정보시스템생물학회 2005년도 BIOINFO 2005
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• pp.319-324
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• 2005

An integrated approach for prostate cancer detection using proteomic data is presented. Due to the high-dimensional feature of proteomic data, the discrete wavelet transform (DWT) is used in the first-stage for data reduction as well as noise removal. After the process of DWT, the dimensionality is reduced from 43,556 to 1,599. Thus, each sample of proteomic data can be represented by 1599 wavelet coefficients. In the second stage, a voting method is used to select a common set of wavelet coefficients for all samples together. This produces a 987-dimension subspace of wavelet coefficients. In the third stage, the Autoassociator algorithm reduces the dimensionality from 987 to 400. Finally, the artificial neural network (ANN) is applied on the 400-dimension space for prostate cancer detection. The integrated approach is examined on 9 categories of 2-class experiments, and also 3- and 4-class experiments. All of the experiments were run 10 times of ten-fold cross-validation (i. e. 10 partitions with 100 runs). For 9 categories of 2-class experiments, the average testing accuracies are between 81% and 96%, and the average testing accuracies of 3- and 4-way classifications are 85% and 84%, respectively. The integrated approach achieves exciting results for the early detection and diagnosis of prostate cancer.

• 정보과학회 논문지
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• 제42권3호
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• pp.379-389
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• 2015

Phase Change Memory (PCM 또는 PRAM), Magneto Resistive RAM (MRAM)과 같은 차세대 비휘발성 메모리가 등장하면서, Dynamic Random-Access Memory (DRAM)을 PRAM으로 대체하는 연구가 활발히 진행되고 있다. 본 논문에서는 PRAM을 메인 메모리로 사용하는 시스템에서 지금까지 널리 사용되고 있는 기존의 조인 알고리즘(블록 네스티드 조인, 소트-머지 조인, 그레이스 해시 조인, 하이브리드 해시 조인)들을 사용했을 때 발생하는 내구성과 성능 문제를 비교, 분석한다. 본 연구의 실험결과에 의하면 기존의 조인 알고리즘들을 PRAM에 맞게 재설계해야 하는 필요성이 제기되었다. 특히, 본 연구는 조인 알고리즘들을 PRAM에 적용했을 때 발생하는 이슈들을 과학적으로 규명한 첫 시도이다. 그리고 기존의 조인 알고리즘들을 PRAM에 적용했을 때 발생하는 내구성과 성능을 비교하기 위한 PRAM 기반의 시스템을 모델링하고 시뮬레이터를 구현한 것에 연구의 의의를 둘 수 있다.

• Archives of Plastic Surgery
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• 제45권5호
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• pp.395-402
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• 2018

Increased emphasis on competency-based learning modules and widespread departure from traditional models of Halstedian apprenticeship have made surgical simulation an increasingly appealing component of medical education. Surgical simulators are available in numerous modalities, including virtual, synthetic, animal, and non-living models. The ideal surgical simulator would facilitate the acquisition and refinement of surgical skills prior to clinical application, by mimicking the size, color, texture, recoil, and environment of the operating room. Simulation training has proven helpful for advancing specific surgical skills and techniques, aiding in early and late resident learning curves. In this review, the current applications and potential benefits of incorporating simulation-based surgical training into residency curriculum are explored in depth, specifically in the context of plastic surgery. Despite the prevalence of simulation-based training models, there is a paucity of research on integration into resident programs. Current curriculums emphasize the ability to identify anatomical landmarks and procedural steps through virtual simulation. Although transfer of these skills to the operating room is promising, careful attention must be paid to mastery versus memorization. In the authors' opinions, curriculums should involve step-wise employment of diverse models in different stages of training to assess milestones. To date, the simulation of tactile experience that is reminiscent of real-time clinical scenarios remains challenging, and a sophisticated model has yet to be established.

• 정보관리학회지
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• 제33권4호
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• pp.159-174
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• 2016

본 연구는 관계 마케팅 분야의 핵심 개념인 전환비용을 도서관 분야에 적용하기 위하여, 문헌 조사 및 면접 조사에 근거하여 대학 도서관 이용자들이 지각하는 전환비용을 정의한 후, 전환비용에 관한 척도를 개발하고 그 타당성을 검증하였다, 또한 210명의 대학 도서관 이용자들을 대상으로 수행된 설문 조사를 통하여 이들이 지각하는 전환비용이 도서관에 대한 태도적, 행동적 충성도에 미치는 영향을 조사하였다. 도서관 이용자들이 지각하는 전환 비용은 이용자가 사용 중인 도서관에서 다른 도서관으로 전환하는 경우 발생하는 절차적, 관계적 비용으로 정의되었다. 조사 결과, 절차적 전환비용 및 관계적 전환비용은 이용자 만족도와 함께 정서적 몰입을 통해 행동적 충성도에 영향을 미치는 것으로 나타났다. 이러한 결과를 토대로 한 이론적, 실무적 시사점이 논의되었다.

• 정보관리학회지
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• 제34권3호
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• pp.67-87
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• 2017

본 연구는 대학 도서관 이용 만족도가 대학생의 대학 생활 만족도에 미치는 영향을 파악하고자 하였다. 이를 위하여 서울 소재 두 곳의 사립 대학교 대학생들 360명을 대상으로 두 차례의 설문조사를 실시하였다. 일차 조사 결과, 시설 만족도와 교육 서비스 만족도의 영향을 통제한 상황에서, 대학 도서관 이용 만족도가 대학 생활 만족도에 유의한 영향을 미치는 것으로 나타났다. 이차 조사에서는 도서관 서비스 품질 변수를 세 가지 차원(직원, 자원 및 서비스, 시설 및 환경)으로 추가하였으며, 분석 결과, 도서관 서비스 품질이 도서관 이용 만족도에 유의한 영향을 미치고, 도서관 이용 만족도는 대학 생활 만족도에 유의한 영향을 미치는 것으로 재확인되었다. 또한 두 집단 분석 결과, 도서관 이용 수준이 높은 집단에서 낮은 집단보다 도서관 이용 만족도가 대학 생활 만족도에 미치는 영향이 더 높은 것으로 나타났다. 이러한 결과를 토대로 한 이론적, 실무적 시사점이 논의되었다.

• Journal of Forest and Environmental Science
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• 제36권3호
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• pp.225-232
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• 2020

Chemical modification of wood is an effective method to enhance the biological durability of wood with no toxic effect on the environment. In this study, wood of Triplochiton scleroxylon was modified using acetylation techniques. A total of one hundred wood blocks, (each 20×20×60 mm) obtained from a 22-year old T. scleroxylon tree were conditioned and acetylated at 120℃ in a bioreactor containing acetic anhydride for 60, 120, 180, 240 and 300 minutes. The percentage weight gain of acetylated wood was determined. The untreated (control) and treated blocks were exposed to Pleurotus ostreatus (white rot fungus) and Fibroporia vaillanti (brown rot fungus) after which moisture content (MC) and weight loss (WL) was monitored for 16 weeks. Data were analysed using descriptive and inferential statistics at p<0.05 level of significance. The percentage weight gain of acetylated wood samples increased with time from 10.4% (60 minutes) to 22.7% (300 minutes). MC of untreated blocks inoculated with Pleurotus ostreatus was significantly higher than those of Fibroporia vaillantii after 16 weeks exposure. There was no significant difference in the MC of the of the acetylated samples for the two fungi after 300 minutes reaction time. The WL of untreated blocks inoculated with Fibroporia vaillantii was higher than those of Pleurotus ostreatus, however, the two fungi showed no significant difference in the WL for the acetylated samples after 16 weeks exposure. Acetylation prevents moisture absorption and inhibition of fungi growth in acetylated wood compared to untreated wood, thereby enhancing the durability of Triplochiton scleroxylon.