• 보존과학연구
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• 통권34호
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• pp.110-122
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• 2013

정선 정암사 수마노탑의 부재는 탄산염암 중에서 돌로마이트이다. 이 탑은 전면에 걸쳐 백화에 의한 화학적 풍화가 진행되고 있고 기단부와 5층 이상의 옥개에서 부재간의 이격이 관찰되고 있다. 또한 부재 이격사이로 생물학적 풍화가 진행되고 있으며 3,5,6,7층 옥개에서 이탈부재가 관찰된다. 건 습식세척으로 생물과 백화일부를 제거하고, 스팀세척으로 잔여백화를 제거하였으며 기단부의 녹흔은 옥살산을 사용한 습포법으로 제거하였다. 이탈부재는 L-30과 Por-rok을 사용하여 고정시켰고, 기단부와 5층 이상의 옥개상부는 Por-rok을 사용하여 방수처리 하였다. 시공 후 방수처리한 구간에서는 백화현상이 나타나는 정도가 미약한것을 확인할 수 있었으므로 방수효과와 동시에 백화저감에도 효과가 있는 것으로 판단된다.

• 한국의사학회지
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• 제33권1호
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• pp.43-57
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• 2020

Essence of the Hwangchil tree (黃漆樹 Dendropanax morbiferus H.Lév.) has been used for various purposes, like waxing emperor's armors, covering an astrology board, or, during the Silla Dynasty, burying it to block something bad in the soil symbolically. Essence of the Hwangchil tree was known to have remarkable preservation effects such as waterproofing, damp-proofing, rust-proofing, and moth-proofing as well as not being easily peeled off from even soft surfaces like paper. There is a record in Prescriptions for Epidemic diseases of Cows, Horses, Sheep, and Pigs (牛馬羊猪染疫病治療方), published in 1541, of Hwangchil that is local to Jeju Island being used instead of benzoin (安息香), of burning Hwangchil, and of making cows inhale its smoke to prevent plague among them. Along the same lines, there are records in the Local Chronicle of Tamra (耽羅志) and the Book of Earth Geography (輿地圖書) that identify Hwangchil with benzoin. In Seonghosaseol (星湖僿說), a book written by Lee Yik in around 1760, it is acknowledged that Hwangchil could be medicinal herb. In 2000, Ahn Duk-Kyun registered the roots and branches of Hwangchil tree as 'Boncho' (本草 herbal medicine) in the Pictorial Book of Korean Medicinals (韓國本草圖鑑) and presented the method of taking it for medical purpose. Researchers have suggested that Hwangchil essence as well as diverse parts of the plant such as its roots, branches, leaves, flowers, fruits, and gum have various meaningful medicinal properties. Regarding the history and recent researches of using Hwangchil tree, it has various medicinal probabilities such as, 'dispersing miasma' (辟邪), 'opening holes' (開竅), 'waking the heart' (醒心), 'smoothing spirits' (安神), 'piercing the block' (疎泄), 'removing the old and welcoming the new' (去故生新). This paper contributes ideas about how to expand the uses of Hwangchil Tree.

• Journal of Advanced Marine Engineering and Technology
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• 제22권1호
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• pp.67-76
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• 1998

Friction materials for brake linings and clutches have severe performance requirements. The principal function of such frictional elements is to convert kinetic energy to heat, and then either to absorb or to dissipate heat. In order to achieve these objectives, the coefficient of friction must be as high as possible, independent of variations in operating conditions, and the necessary energy conversion must be accomplished with a minimum of wear on the contacting parts. In this study, Al powder, Al bronze powder and Mo powder used in general for automobile brake was sprayed on automobile brake disc to restrain rust and to maintain friction performance. Dynamo and corrosion tests have been carried out. It is concluded that the sprayed disc with Al bronze powder has the most improved frictional performance and anti-corrosive characteristics. The main results obtained can be summarized as follows; 1. From the corrosion current density test for gray cast iron and sprayed disc with powders of Al, Al bronze and Mo, it was cleared that the spray treatment with Al bronze powder showed the most superior anti-corrosive characteristics than other powders. 2. By anode polarization toward the noble direction from corrosion potential, corrosion current density with sprayed brake disc by Al-bronze powder was the lowest. 3. Mean frictional coefficients obtained from dynamo test are as follows : the sprayed disc with Al(99.99%) powder was 0.190 ; the sprayed disc with Al-bronze powder was 0.312 ; the sprayed disc with Mo powder was 0.257 ; the non-sprayed disc of gray cast iron was 0.331. In the case of the sprayed disc Al-bronze powder showed the most excellent frictional characteristics . 4. Amount of burnish quantity obtained from burnish test by dynamometer is as follows : the sprayed disc with Al-powder was 1.079 mm : the sprayed disc with Al-bronze powder was 0.155 mm : the sprayed disc with Mo powder was 0.253 mm : the non-sprayed disc of gray cast iron was 0.241 mm. Al-bronze powder also showed the most excellent burnish characteristics.

• 동력기계공학회지
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• 제10권2호
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• pp.104-110
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• 2006

Corrosion has been around for all of recorded history. Cathodic protection is the electrical solution to the corrosion problem. Corrosion is not exactly a new topic. It has been around since the beginning of time. Corrosion is simply the loss of material resulting from current leaving a metal, following through a medium, and returning to the metal at a different point. Corrosion takes many forms and has various names, such as oxidation, rust, chemical, and bacteria action. Regardless of the agent, all corrosion is the result of electrical current flow. Various methods are used to treat corrosion or to try to prevent ti. Some of these include chemical treatment. coatings, and electrical current. Especially, proper impressed current can stop corrosive action on the protected surface. In this article, we introduce the Impressed Current Cathodic Protection (ICCP) Control and monitoring system developed by ourselves. The ICCP system is composed of a power supply, anode, reference electrode and controller. The main issue is to control the current flow on the desired value such that it is possible to force a metal to be more negative(cathodic) than the natural state. From the this process, we can achieve the cathodic protection. Of course, in the developed system, the necessary functions are possessed, such as remote control, monitoring of system fault detection etc. Some experimental results show the system performance and usefulness.

• 아시안잔디학회지
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• 제20권1호
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• pp.1-10
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• 2006

본 실험은 한국잔디 신품종 '밀록'(특허출원: 10-2005-0110051)의 개발에 관한 것으로, 국내외에서 수집한 한국잔디류중 우수계통 MJ8를 선발 한 후, 인공자식을 통하여 변이를 확대하였으며, 이들 중에서 품질이 우수한 계통(MJ8S-9)을 선발한 것이다. 신품종 '밀록'은 밀도가 기존의 한국잔디류와 비교해 가장 높았고, 또한 녹색도가 높아 우수한 잔디 품질을 보이며, 녹병에 대한 저항성이 높았다. 형태적 특성으로 엽폭은 4.2rnm로 중엽형이며, 잎 각도는 52.5도로 넓어 광합성 효율이 높다. 지면으로부터 최하위 엽의 잎몸 기부까지의 길이가 1.9cm로 짧아 낮게 깎을 수 있는 특성을 갖고 있다. 또한 '밀록'은 지상 포복경의 색이 황록색이며, RAPD 분석에서 특이밴드를 갖고 있어 다른 잔디류와 식별성이 높은 영양 번식형 신품종이다.

• Corrosion Science and Technology
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• 제2권4호
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• pp.183-188
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• 2003

Corrosion of carbon and weathering steels were evaluated under 3 environmental exposures in Thailand (urban, rural and marine) for a year. The seasonal study was designed to determine different corrosion mechanisms by 6 months of dry season and 6 months of rainy season in a year. The sheltered exposure racks were used to determine the washing effect of min. At each site, climatic and pollutants analyses were carried out. The present study showed that the difference in corrosion rates of carbon and weathering steels was not so distinguished in both rural (AIT) and urban (TISTR) environments. The corrosion rate of weathering steel was somewhat lower than that of carbon steel and the decreasing tendency of corrosion rate with time was slightly higher for weathering steel than for carbon steel. In marine (Rayong) environment, the corrosion rate was higher and the effect of wet and dry seasons was observed. The corrosion rate in 6 dry months was higher for direct exposure than for sheltered exposure. However, in 6 rainy months. the corrosion rate of sheltered exposure was higher than that of direct exposure. In direct exposure for I year, that is, the first 6 dry months and the next 6 rainy months, the corrosion rate decreased with time. but in sheltered exposure, the corrosion rate did not decrease with time. instead, increased in the next 6 rainy months. This indicated that the protect ive layer formed in the first 6 dry months could be destroyed by high deposition of chloride to r sheltered exposure in the next 6 rainy months; whereas the rust layer for direct exposure could be kept sound due to washing effect in rainy season, even though the deposition rate of chloride was almost the same for direct and sheltered exposures. In marine environment, the weathering steel showed higher corrosion resistance than carbon steel but its corrosion rate was higher than those in other environments.

• 대한조선학회 특별논문집
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• 대한조선학회 2006년도 특별논문집
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• pp.46-52
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• 2006

For ships, heat resistant coating is applied on the aluminized steel pipe systems dealing with high temperature steam over $200^{\circ}C$. The coatings on these steam pipes should retain both heat resistance and anti-corrosion properties to provide long-term resistance against coating defects (rust, delamination and crack) under the harsh outdoor environment including repeated seawater wetting and condensation. Thus, it is important to improve the coating qualities and to reduce maintenance works for these steam pipe systems. In this study, five different commercial heat resistant coatings (A, B, C, D, E) were selected for evaluation. Various physical properties of these coatings were evaluated on the coatings applied on the aluminized steam pipes. FT-IR analysis was also employed to identify the factors contributing the degree of heat resistance and durability of each coating material. The results indicated that the heat resistance capacity of coatings increased with the increase of silicon content as well as the decrease of substituent content. Both products C and D showed the best coating qualifies, which can be standard coating systems for future steam pipe areas.

• 열처리공학회지
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• 제19권4호
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• pp.200-207
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• 2006

In addition to the basic properties of the base and top coating agents, corrosion resistance of non-chrome magni 565 coating and characteristics of coating film when coated to steel substrate were studied. The system had a good wettability at room temperature. Moreover, both the contact angle and surface tension were affected little by the viscosity of coating agent and surface roughness of the steel substrate. And the samples coated with optimal conditions showed a great corrosion resistance in salt spray test with 1500 hours or longer of initial appearance time of rust. The coating film was composed of overlapping layer of zinc and aluminium flakes, and the thickness of base coat increased with an increase of base coat viscosity. Based on the C-F peaks of 1,1-Difluoroethaen homo-polymer, it was thought that the base coat was an inorganic polymer bond layer. Meanwhile, the top coat showed C-F peaks of polytetrafluoroethylene with C-H peaks of phenol in FT-IR analysis. From the lower weight loss of base coat in TG analysis, it was thought that cross linking density of base coat was larger than that of top coat. It was thought that the small exothermic reactions observed in DSC curves were due to the thermosetting resins contained in the coating agents. Compared to the non-coated specimen, the coated sample showed more higher polarization resistance and corrosion potential with lower corrosion current density.

• 원예과학기술지
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• 제30권3호
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• pp.325-328
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• 2012

'My Sun'은 경기도농업기술원에서 2009년도에 육성한 분화용 국화 신품종으로 2005년도에 오렌지 계열 분화용 국화 'Omega Time Orange' 품종을 모본으로 하고 흰색 'Tasman' 품종을 부본으로 교배하여 얻었다. 이 품종은 노란색 꽃잎을 가진 초장이 짧은 홑꽃이다. 2006-2009년까지 춘계 촉성재배와 동계 억제재배를 포함하는 특성검정을 수행하였다. 'My Sun' 품종의 자연개화기는 10월 13일이며, 전조재배와 차광재배로 개화가 조절되어 주년 재배가 가능하다. 화경은 21mm, 착화수는 본당 34.4매이고 꽃잎수는 20.4매이다. 엽색은 녹색(Green Group 137A)이고 초장은 13.3cm이다. 개화소요일수는 춘계에는 단일처리 후 42일 정도이며, 분지수는 겨울철에는 3.4개 정도를 가진다. 이 품종은 흰녹병 저항성이고 대조품종에 비해 기호도가 높은 편이었다.

• Weed & Turfgrass Science
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• 제3권2호
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• pp.121-129
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• 2014

본 연구에서는 2013년 잔디 재배지에서 발생하는 병해와 Rhizoctonia spp. 밀도를 조사하였다. 진주포장에서 갈색퍼짐병(Large patch)이 35% 발생하였고, 9월에 녹병이 발생하였다. 갈색마름병은 남해지역에서 9월과 10월을 거쳐 발생하였으며 7월 초 피시움잎마름병이 대발생 하였고, 동전마름병(Dollar spot)의 경우 전체 면적에 3%에 달하는 면적이 심각하게 피해를 입은 포장도 있는 것으로 조사되었다. 진주 대평에서 페어리링과 갈색퍼짐병이 발생하였다. 전북고창에서는 페어리링과 테이크올패치가 나타났으며 충북청주에서는 다수의 포장에서 갈색마름병이 관찰되었다. 경기평택에서는 갈색마름병, 도열병, 썸머패취, 커브라리아엽고병, 커브라리아엽고병과 녹조의 복합피해가 나타났다. 전염원 밀도는 장성, 진주, 산청과 남해지역 모두 시간이 지날수록 증가하는 것으로 나타났다. 병 발생과 병원균을 조사한 결과 골프코스에서 나타나는 병해와 유사한 것으로 나타났다.