• 한국결정학회지
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• 제7권1호
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• pp.64-72
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• 1996

증기압 제어를 위한 저온부를 없애고, 고온부의 단일 온도영역만으로 GaAs 단결정을 성장 시키는 단일 온도대역 수평 Bridgman(1-T HB: single temperature zone horizontal Bridgman)방식에서는 증기압에 상응할만한 반응관 내부의 압력을 As 초과 유입량의 기화에 의하여 유지해야 하므로 그 양을 정밀하게 결정해 주어야 한다. 이것을 위하여, 우선적으로 Ga-As 계에서의 열화학적 특성을 규명하였고, 이에 근거하여 단일 온도대역 수평 Bridgman 법으로 결정성장할 때의 As 초과 유입량을 GaAs 장입량, 반응관 칫수, 온도구배 등에 의한 일반해로 유도하였다. 따라서 단일 온도대역 수평 Bridgman 법에 의한 GaAs 단결정 성장의 이론적 근거를 마련하였다.

• 대한건축학회연합논문집
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• 제20권6호
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• pp.9-16
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• 2018

The purpose of this research was influenced by the historical background of Japanese modern architecture by the circulation of Kuma Kengo's architectural works and he wanted to look at the values and directions he was pursuing and how they were expressed in his works. The results of the review are summarized as follows. First, metabolism was developed as a reaction of modernism in modern architecture, focusing on growth through infinite reproduction by looking at architecture and cities as organisms and by using unit space as cells. Kuma Kengo, on the other hand, argues that focusing on the possibility of decimation of unit members by sequencing the elements that make up the space smaller than the unit space is closer to an ecological architecture. Second, what Kuma Kengo says is "erase the architecture" that is naturally related to the environment and disappears when its use is exhausted. His argument is expressed in individual architectural works through 'visual erase', 'particle painting of materials' and 'independence through dependency.' Through this, Kuma Kengo's ecological architectural languages were influenced by the ecological causes of metabolism, but they differed from the perspective of seeing architectural circulation as an organism. If metabolism was intended to realize circulation with growth potential based on the module of unit space, Kuma Kengo sought to implement circulation with the extinction of the unit members of space.

• 한국약용작물학회지
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• 제27권2호
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• pp.75-85
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• 2019

Background: Medicinal plants are widely used in Asia. They have proven to be an invaluable asset in modern drug discovery and their demand has been steadily increasing across various industries. Methods and Results: Using 4,867 valid patents related to 12 oriental medicinal plants of 10 country groups, the growth and development potential of patents was evaluated. The cites per patent (CPP) and patent family size (PFS) indices were used to evaluate the market capability and technological level of the collected patents. Meanwhile, the patent impact index (PII) and technology strength (TS) were used to compare the technological competitiveness of patents among various technology types and markets. Both CPP and PFS indices showed that magnolia-vine and balloon flower have numerous core or original patents. Furthermore, an increase in both PII and TS indices was observed. A newly designed intellectual property multi-layer (IPM) model predicted that the medicine, genome and cosmetic categories have a high possibility of patent application growth. Conclusions: The IPM model can be used to provide the scope of particular technology fields for patent development. In addition, this study can assist patents to advance in the international market and guide the development of a national industrial strategy.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제42권
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• pp.23.1-23.11
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• 2020

Background: 4-Hexylresorcinol (4HR) is able to increase angiogenesis. However, its molecular mechanism in the human endothelial cells has not been clarified. Methods: As endothelial cells are important in angiogenesis, we treated the human umbilical vein endothelial cells (HUVECs) with 4HR and investigated protein expressional changes by immunoprecipitation high-performance liquid chromatography (IP-HPLC) using 96 antisera. Results: Here, we found that 4HR upregulated transforming growth factor-β (TGF-β)/SMAD/vascular endothelial growth factor (VEGF) signaling, RAF-B/ERK and p38 signaling, and M2 macrophage polarization pathways. 4HR also increased expression of caspases and subsequent cellular apoptosis. Mechanistically, 4HR increased TGF-β1 production and subsequent activation of SMADs/VEGFs, RAF-B/ERK and p38 signaling, and M2 macrophage polarization. Conclusion: Collectively, 4HR activates TGF-β/SMAD/VEGF signaling in endothelial cells and induced vascular regeneration and remodeling for wound healing.

• 한국직업건강간호학회지
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• 제31권4호
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• pp.187-197
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• 2022

Background: This study explores the pathways of nurse turnover in long-term care hospitals (LTCHs) and its underlying conditions in Korea. Although the factors of staying or leaving of nurses in LTCHs have been reported, few studies have examined the trajectory and conditions of nurses staying in and leaving LTCHs. Methods: A qualitative study design with a grounded theory approach was conducted. Data were collected in one-to-one interviews. Purposive and theoretical sampling led to the inclusion of 20 registered nurses from 15 LTCHs in South Korea. Results: Seeking work-life balance was the core category of the nurses' turnover pathway. The consequences of the nurses' turnover pathway were categorized into three groups: thriving, surviving, and leaving. Thriving nurses found meaning in their work, fostered good relationships, and saw opportunities for growth. Surviving nurses were enduring their jobs in LTCHs, having a work-life balance, and supportive nursing leaders. Leaving group nurses wished to leave LTCHs due to a lack of professional growth, unappealing work, continued conflict, and social stigma. Conclusion: This study provided the trajectory and conditions for nurses to enter, stay, move, or leave. Understanding the pathways for staying or leaving can be used as a strategy for successful retention of registered nurses in LTCHs.

• 대기
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• 제33권5호
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• pp.457-475
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• 2023

Accurately predicting localized heavy rainfall is challenging without high-resolution mesoscale cloud information in the numerical model's initial field, as precipitation intensity and amount vary significantly across regions. In the Korean Peninsula, the radar observation network covers the entire country, providing high-resolution data on hydrometeors which is suitable for data assimilation (DA). During the pre-processing stage, radar reflectivity is classified into hydrometeors (e.g., rain, snow, graupel) using the background temperature field. The mixing ratio of each hydrometeor is converted and inputted into a numerical model. Moreover, assimilating saturated water vapor mixing ratio and decomposing radar radial velocity into a three-dimensional wind vector improves the atmospheric dynamic field. This study presents radar DA experiments using a numerical prediction model to enhance the wind, water vapor, and hydrometeor mixing ratio information. The impact of radar DA on precipitation prediction is analyzed separately for each radar component. Assimilating radial velocity improves the dynamic field, while assimilating hydrometeor mixing ratio reduces the spin-up period in cloud microphysical processes, simulating initial precipitation growth. Assimilating water vapor mixing ratio further captures a moist atmospheric environment, maintaining continuous growth of hydrometeors, resulting in concentrated heavy rainfall. Overall, the radar DA experiment showed a 32.78% improvement in precipitation forecast accuracy compared to experiments without DA across four cases. Further research in related fields is necessary to improve predictions of mesoscale heavy rainfall in South Korea, mitigating its impact on human life and property.

• 산경연구논집
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• 제15권6호
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• pp.1-7
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• 2024

Purpose: This study aims to explore the significance and potential strategies for revitalizing local currency systems. Designed for use within specific regions or communities, local currencies play a crucial role in supporting and revitalizing local economies. By promoting local consumption and supporting local businesses, local currencies contribute to economic growth and job creation at the community level. Research design, data and methodology: The research methodology involves a comprehensive review of existing literature and various case studies to analyze the effectiveness and sustainability of local currencies. The literature review investigates the theoretical background and diverse implementation cases of local currencies, while the case studies identify the success factors and challenges faced by actual local currency initiatives. Results: This paper confirms that local currencies contribute to economic growth and job creation at the community level by promoting local consumption and supporting local businesses. Additionally, this study investigates the economic, social, and environmental impacts of local currencies. Conclusion: In conclusion, this study analyzes the challenges faced by local currency systems and proposes strategies to enhance their effectiveness and sustainability. These strategies are expected to provide practical assistance in the development and implementation of local currencies, contributing to the revitalization of local economies and the sustainable development of local communities.

• 한국산학기술학회논문지
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• 제15권4호
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• pp.2376-2381
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• 2014

2008년 글로벌금융위기 이후 더욱 심화된 기업간 양극화 문제의 해소와 관련하여 현재 대중소기업간 동반성장의 필요성이 그 어느 때보다 크게 대두되고 있다. 이에 본고는 KISVALUE를 통해 517개(대기업 80개, 중소기업 437개) 경기지역 소재 IT기업의 15년(1996~2010년)간의 기업패널 자료를 구축하고 pooled OLS 기법을 이용하여 Gibrat 법칙 및 Jovanovich 가설의 성립여부에 대한 엄밀한 분석을 시도하였다. 실증분석 결과, 기업의 규모를 대리하는 추정계수 값이 1보다 작게 나타나 기업의 규모와 성장률간에는 상관관계가 없다는 Gibrat법칙은 성립하지 않는 것으로 나타났다. 반면, 기업의 업력을 대리하는 추정계수 값이 유의하게 음(-)의 값을 나타내고 있어 기업의 업력과 성장률간에는 역의 상관관계가 있다는 Jovanovic 가설은 성립하는 것으로 나타났다. 이상의 분석결과는 대체로 기업의 업력이 짧은 중소기업은 업력이 긴 대기업보다 성장률이 높을 수 있음을 의미하고, 또한 수출 및 기술혁신 지향적인 기업일수록 기업의 성장률이 높은 것으로 나타났다.

• 한국환경농학회지
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• 제32권4호
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• pp.273-278
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• 2013

BACKGROUND: Total petroleum hydrocarbons (TPH), which are main materials of soil contamination by oil, are a term used for any mixture of hydrocarbons. Korea Ministry of Environment established the maximum permissible level of TPH in farmland by 500 mg/kg, and reported that the TPH level of soil in 266 installation such as gas station, transport company, and military unit ranged from 1,356 to 55,117 mg/kg and were much higher than the maximum permissible level in 2011. METHODS AND RESULTS: To determine the effect of TPH on crops, we investigated the effect of gasoline, kerosene, and diesel on the germination and radicle growth of mainly consumed crops. The germination rates of control in investigated all crops ranged from 80.0-100%. The germination and radicle growth in majority of investigated crops were not inhibited even at 2,500 mg/L. However, germination in onion, leek, and green perilla and radicle growth in leek, rape, tomato, and green perilla were significantly inhibited by increasing concentrations of gasoline, kerosene and diesel treatment. Germination and radicle growth inhibition of green perilla by kerosene and diesel were the highest, the percent inhibition at the 500 mg/L were 100 and 98.6%, 100 and 88.2%, respectively. 50% inhibition of germination in green perilla by kerosene and diesel were 39.96 and 29.87 mg/L, and 50% inhibition of radicle growth were 52.76 and 177.96 mg/L, respectively. Conclusion(s): These results suggest the possibility that the maximum permissible level of TPH might to be established general level with exception by crops.

• Journal of Animal Science and Technology
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• 제58권10호
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• pp.37.1-37.10
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• 2016

Background: Providing of insufficient nutrients limits the potential growth of pig, while feeding of excessive nutrients increases the economic loss and causes environment pollution. For these reasons, phase feeding had been introduced in swine farm for improving animal production. This experiment was conducted to evaluate the effects of dietary energy levels and phase feeding by protein levels on growth performance, blood profiles and carcass characteristics in growing-finishing pigs. Methods: A total of 128 growing pigs ([Yorkshire ${\times}$ Landrace] ${\times}$ Duroc), averaging $26.62{\pm}3.07kg$ body weight, were assigned in a $2{\times}4$ factorial arrangement with 4 pigs per pen. The first factor was two dietary energy level (3,265 kcal of ME/kg or 3,365 kcal of ME/kg), and the second factor was four different levels of dietary protein by phase feeding (1growing(G)-2finishing(F) phases, 2G-2F phases, 2G-3F phases and 2G-3F phases with low CP requirement). Results: In feeding trial, there was no significant difference in growth performance. The BUN concentration was decreased as dietary protein level decreased in 6 week and blood creatinine was increased in 13 week when pigs were fed diets with different dietary energy level. The digestibility of crude fat was improved as dietary energy levels increased and excretion of urinary nitrogen was reduced when low protein diet was provided. Chemical compositions of longissimus muscle were not affected by dietary treatments. In backfat thickness ($P_2$) at 13 week, pigs fed high energy diet had thicker backfat thickness (P = 0.06) and pigs fed low protein diet showed the trend of backfat thinness reduction (P = 0.09). In addition, water holding capacity was decreased (P = 0.01) and cooking loss was increased (P = 0.07) as dietary protein level reduced. When pigs were fed high energy diet with low subdivision of phase feeding, days to 120 kg market weight was reached earlier compared to other treatments. Conclusion: Feeding the low energy diet and subdivision of growing-finishing phase by dietary protein levels had no significant effect on growth performance and carcass characteristics. Also, phase feeding with low energy and low protein diet had no negative effects on growth performance, carcass characteristics but economical profits was improved.