• Journal of Korean Society of Forest Science
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• v.3 no.1
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• pp.36-42
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• 1963

The results obtained are summarized as follows: 1. In both years of 1960 and 1961, the flowering times, fading times of flowers, mature times of fruits of 63 chestnut varieties grown at Choosan area, Chon Nam, have been investigated. Almost the ages of trees were 26-year-old and they are growing on the brown forest soil well drained with relatively thick surface soil. 2. Non-significant difference in flowering time by the varieties has been found between the years. The carliests in floweing time are Toyotama-wase, The isho-wase, Asami-wase, Umehira-wase, i.e., bloomed on May, 22, or a little later. 3. The fading dates of flowers of each varieties almost linearly correlated to the flowering date. The blooming period of each varieties was about 10 to 12 days. 4. Linear correlation between mature time and blooming time are observed, i.e., the earlier the blooming time comes, the earlier is the mature time of chestnut fruit. 5. The varieties having the smallest sized seed, are Otomune and Boji-kuri, however, those having the large one, are Ho-gin, Katayama, Ohara-wase.

• Korean Journal of Poultry Science
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• v.32 no.1
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• pp.15-21
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• 2005

This Study was conducted to investigate the effects of microbial phytase in low phosphirus and calcium level diet on the performance and nutrient digestibility in laying hens. One hundred ninety two, 50 wks old, ISA brown commerical layers were used for 12 weeks feeding trial after 7-d adjustment period. Four dietary treatments included CON(control; Co.), P2 ($0.06\%$ Natuphos, BASF) and P3 ($0.06\%$ PHOSMAX, GENOFOCUS). Ca and available P concentrations of P1, P2 and P3 were 90 and $50\%$ of NRC recommecdations to accentuate difference in response to phytase availability. In whole period, egg production was not affected by treatments. At 12 weeks, egg weight was significantly increased in adding phytase treatments (P<0.05). Egg shell thickness was increased in P1, P2 and P3 treatments compared with control (P<0.05) at 9 weeks. Ca concentration of serum tended to decrease in P1 treatment without significant difference (P>0.05). Ca and P concentrations of tibia were higher in layers fed dietary phyrase than those fed control diet without significant difference (P>0.05). Digestibilities of DM, N and ash were improved in P1 treatment compared with P2 and P3 treatments (P<0.05). Ca and P digestibilities were the highest in P2 treatment (P>0.05), but was not significant difference between control and P1 treatments.

• Tuberculosis and Respiratory Diseases
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• v.58 no.3
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• pp.276-284
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• 2005

Backgraound : There have been many reports on the pathogenesis of sepsis-induced acute respiratory distress syndrome(ARDS) but, the precise mechanism has not been elucidated. This study examined the protective effect of an inhibition of platelet activating factor(PAF) remodeling and the adhesion molecule on the oxidative stress of the lungs in rats with an endotoxin induced acute lung injury(ALI). Methods : ALI was induced in Sprague-Dawley rats by instilling an E-coli endotoxin into the trachea. Ketotifen and fucoidan were used respectively to inhibit PAF remodeling and adhesion molecule. The lung leak index, lung myeloperoxidase(MPO) activity, bronchoalveolar lavage(BAL) fluid neutrophil count and lyso PAF acetyltransferase activity(AT), were measured and an ultrastructural study and cytochemical electron microscopy were performed. Results : The lung leak index, lung MPO activity, BAL fluid neutrophil count and lyso PAF AT activity was higher in the endotoxin-treated rats. In addition, severe destruction of the pulmonary architecture and increased hydrogen peroxide production were identified. These changes were reversed by ketotifen. However, fucoidan did not appear to have any protective effects. Conclusion : The inhibition of PAF remodeling appeared to be effective in decreasing the endotoxin-induced ALI. In addition, this effect might be derived from the inhibition of neutrophilic oxidative stress. However, the inhibition of the adhesion molecules by fucoidan appeared to be ineffective in decreasing the endotoxin-induced ALI.

• The Journal of Engineering Geology
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• v.28 no.1
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• pp.69-79
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• 2018

The Korean government attempts to reduce $CO_2$ emissions by 37% to 314.7 Mt $CO_2$, down from the estimated 850.6 Mt $CO_2$ until 2030 in order to confront green house effect. In this context, in 2014, Korean government launched $CO_2$ Storage Environmental Management Research (K-COSEM) Center for carrying out pilot-scale research on $CO_2$ leakage from underground $CO_2$ storage facilities. For the detection of $CO_2$ leakage, it is necessary to identify hydrologeological and geophysical characteristics of the subject area. In the study site of Naesan-ri, Daeso-myeon, Eumseong-gun, Chungbuk Province, two times injection tests (June 28-July 24, 2017 and August 07-September 11, 2017) of $CO_2$ and $SF_6$ dissolved waters, respectively, was conducted to understand the leakage behavior of $CO_2$ from underground. The injection well was drilled to a depth of 24 m with a 21-m casing and screen interval of 21~24 m depth. Two times resistivity surveys on August 18, 2017 and September 1, 2017, were conducted for revealing the flow of the injected water as well as the electrical properties of the study site. The study results have shown that the high-resistivity zone and the low-resistivity zone are clearly contrasted with each other and the flow direction of the injected water is similar to natural groundwater flow. Besides, the low resistivity zone is widely formed from the depth of injection to the shallow topsoil, indicating that the weathered zone of high permeability has high $CO_2$ leakage potential.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2018.06a
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• pp.135-135
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• 2018

천이금속 질화물 코팅은 우수한 기계적 특성들로 인해 공구 코팅으로 많이 사용 되어왔다. 그 중에서도 특히 Cr계 경질 코팅은 높은 경도와 낮은 표면조도, 우수한 마찰특성 등 뛰어난 기계적 특성을 나타내므로 공구 코팅으로의 적용 가능성이 크다. 그러나 최근 공구산업의 발전으로 인해 공구가 더욱 가혹한 환경에서 사용됨에 따라, 공구의 수명을 향상시키고 보호하기 위해 코팅의 높은 밀착력이 요구되고 있으며, 모재와 코팅 사이에 중간층을 합성함으로써 공구의 밀착력을 향상시키는 연구가 활발히 진행되고 있다. 이전 연구에서 모재/중간층/코팅간의 경도와 탄성계수 비율(H/E ratio)의 구배가 코팅의 밀착력에 큰 영향을 미치는 것으로 확인되었다. 그러므로, WC 모재와 Cr계 코팅의 중간값의 H/E ratio를 갖는 중간층의 합성을 통해 코팅의 밀착력을 향상시킬 수 있을 것으로 판단된다. 본 연구에서는, 코팅의 밀착력을 향상시키기 위해 다양한 중간층을 증착한 CrZrN, CrAlN 코팅을 비대칭 마그네트론 스퍼터링 장비를 이용하여 합성하였다. 모재로는 디스크 형상의 WC-6wt.%Co 시편을 사용하였고 Cr, Zr, Si, Al single 타겟을 이용하여 Cr, CrN, CrZrN, CrZrSiN 등의 중간층이 증착된 코팅을 합성했다. 코팅의 합금상, 경도 및 탄성계수, 미세조직 및 조성, 표면 조도을 확인하기 위해 X-ray diffractometer (XRD), Fischer scope, field-emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDS), atomic force microscopy를 사용하였고, 코팅의 밀착 특성을 분석하기 위해 scratch tester와 optical microscopy (OM)를 이용하였다. 코팅의 내열성을 확인하기 위해 코팅을 furnace에 넣어 공기중에서 500, 600, 700, 800, 900, $1,000^{\circ}C$로 30분 동안 annealing 한 후에 nano-indentation을 사용하여 경도를 측정하였다. CrZrN 및 CrAlN 코팅을 나노 인덴테이션으로 분석한 결과, 모든 코팅의 경도(33.4-35.8 GPa)와 탄성계수(384.1-391.4 GPa)는 중간층의 종류에 상관없이 비슷한 값을 보인 것으로 확인됐다. 그러나, 코팅의 마찰계수는 중간층의 종류에 따라 다른 값을 보였다. CrZrN 코팅의 경우 CrN 합금상 중간층을 갖을 때 가장 낮은 값을 보였으며, CrAlN 코팅의 경우 CrN/CrZrSiN 중간층을 증착하였을때 마찰계수는 0.34로 CrZrN 중간층을 증착하였을 때(0.41)에 비해 낮은 값을 보였다. 또한, 코팅의 마모율 및 마모폭도 비슷한 경향을 보인 것으로 보아, CrN/CrZrSiN 중간층을 합성한 CrAlN 코팅의 내마모성이 상대적으로 우수한 것으로 판단된다. 코팅의 밀착력의 경우도 마찰계수와 비슷한 경향을 보였다. 이것은 중간층의 H/E ratio가 코팅의 내마모성에 미치는 영향에 의한 결과로 사료된다. H/E ratio는 파단시의 최대 탄성 변형율로써, 모재/중간층/코팅의 H/E ratio 구배에 따라 코팅 내의 응력의 완화 정도가 변하게 된다. WC 모재 (H/E=0.040)와 CrAlN 코팅(H/E=0.089) 사이에서 CrN, CrZrSiN 중간층의 H/E ratio는 각각 0.076, 0.083으로 모재/중간층/코팅의 H/E ratio 구배가 점차 증가함을 확인 할 수 있었고, 일정 응력이 지속적으로 가해지면서 진행되는 마모시험중에 CrN과 CrZrSiN 중간층이 WC와 CrAlN 코팅 사이에서 코팅 내부의 응력구배를 완화시키는 역할을 함으로써 CrAlN 코팅의 내마모성이 향상된 것으로 판단된다. 모든 코팅을 열처리 후 경도 분석 결과, CrN/CrZrSiN 중간층을 증착한 CrAlN 코팅은 $1,000^{\circ}C$까지 약 28GPa의 높은 경도를 유지한 것으로 확인 되었고, 이는 CrZrSiN 중간층 내에 존재하는 SiNx 비정질상의 우수한 내산화성에 의한 결과로 판단된다.

• Journal of the Daesoon Academy of Sciences
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• v.35
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• pp.217-253
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• 2020

This study analyzes the principles of the 'Earthly Paradise' (仙境, the realm of immortals), 'Virtuous Concordance of Yin and Yang' (陰陽合德), and the 'Reordering Works of Heaven and Earth' (天地公事) while combining them with Joseon art. Therefore, this study aims to discover the context wherein the concept of Taiji in 'Daesoon Truth,' deeply penetrates into Joseon art. Doing so reveals how 'Daesoon Thought' is embedded in the lives and customs of the Korean people. In addition, this study follows a review of the sentiments and intellectual traditions of the Korean people based on 'Daesoon Thought' and creative works. Moreover, 'Daesoon Thought' brings all of this to the forefront in academics and art at the cosmological level. The purpose of this research is to vividly reveal the core of 'Daesoon Thought' as a visual image. Through this, the combination of 'Daesoon Thought' and Joseon art will secure both data and reality at the same time. As part of this, this study deals with the world of 'Daesoon Thought' as a cosmological Taiji principle. This concept is revealed in Joseon art, which is analyzed and examined from the viewpoint of art philosophy. First, as a way to make use of 'Daesoon Thought,' 'Daesoon Truth' was developed and directly applied to Joseon art. In this way, reflections on Korean life within 'Daesoon Thought' can be revealed. In this regard, the selection of Joseon art used in this study highlights creative works that have been deeply ingrained into people's lives. For example, as 'Daesoon Thought' appears to focus on the genre painting, folk painting, and landscape painting of the Joseon Dynasty, attention is given to verifying these cases. This study analyzes 'Daesoon Thought,' which borrows from Joseon art, from the perspective of art philosophy. Accordingly, attempts are made to find examples of the 'Virtuous Concordance of Yin and Yang' and Tai-Ji in Joseon art which became a basis by which 'Daesoon Thought' was communicated to people. In addition, appreciating 'Daesoon Thought' in Joseon art is an opportunity to vividly examine not only the Joseon art style but also the life, consciousness, and mental world of the Korean people. As part of this, Chapter 2 made several findings related to the formation of 'Daesoon Thought.' In Chapter 3, the structures of the ideas of 'Earthly Paradise' and 'Virtuous Concordance of Yin and Yang' were likewise found to have support. And 'The Reordering Works of Heaven and Earth' and Tai-Ji were found in depictions of metaphysical laws. To this end, the laws of 'The Reordering Works of Heaven and Earth' and the structure of Tai-Ji were combined. In chapter 4, we analyzed the 'Daesoon Thought' in the life and work of the Korean people at the level of the convergence of 'Daeesoon Thought' and Joseon art. The analysis of works provides a glimpse into the precise identity of 'Daesoon Thought' as observable in Joseon art, as doing so is useful for generating empirical data. For example, works such as Tai-Jido, Ssanggeum Daemu, Jusachaebujeokdo, Hwajogi Myeonghwabundo, and Gyeongdodo are objects that inspired descriptions of 'Earthly Paradise', 'Virtuous Concordance of Yin and Yang,' and 'The Reordering Works of Heaven and Earth.' As a result, Tai-Ji which appears in 'Daesoon Thought', proved the status of people in Joseon art. Given all of these statements, the Tai-Ji idea pursued by Daesoon Thought is a providence that follows change as all things are mutually created. In other words, it was derived that Tai-Ji ideology sits profoundly in the lives of the Korean people and responds mutually to the providence that converges with 'Mutual Beneficence.'