• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2002년도 Proceedings of the International Welding/Joining Conference-Korea
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• pp.355-360
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• 2002

ElectroSlag Strip Overlaying (ESSO) process has been around since 1970. ESSO process had limited acceptance due to a few problems associated with the use of this process in its very early stage. Limited knowledge and, most significantly, poor quality of the equipment and welding flux gave the ESSO process a bad name. However, this process is well accepted today and used in North America, Europe and Japan. The ESSO process provides low dilution overlays at high deposition rates, excellent and consistent deposit chemistry with excellent surface quality, and virtually no defects. Capitan has taken this process one step further through extensive research and development of the process itself as well as the equipment. The improvement brought to the process warranted the issuance in May 2000 of an US patent. This study demonstrates the feasibility of this process with immediate positive production results. The main achievements of this work are as follows: $\textbullet$ Development of six various strip-flux combinations on three different base materials: carbon steel, $\frac{1}{4}$ Cr/.5 Mo and 2 $\frac{1}{4}$ Cr/l Mo, fully tested with: penetrant, ultrasound, bends, hardness, overlay chemistry, corrosion and hydrogen disbonding. $\textbullet$ 12" dia. 90 hot formed elbows from straight pipe electroslag overlayed with "1 layer" and "2 layer" Alloy 625 $\textbullet$ a very unique development of miniaturized overlaying equipment able to perform overlay in pipe with diameters as low as 10" (254 mm). This development has large applications in the field of offshore, petrochemical, refining, pulp and paper and power generation industries. The aftermath of this development was its immediate acceptance by major end users with the completion of four projects of overlayed pipe in the USA and Far East Asia.

• 대한치과보철학회지
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• 제27권2호
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• pp.53-78
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• 1989

This study was taken to observe the changes of the residual stress in the alloy and to measure 3 dimensional distortions of the long span ceramo-metal bridge. The materials used in this study were Pors-on 4 (Pd-Ag alloy), and Ceramco and Vita VMK 68 powders. The residual stress of the alloy was measured on the six specimens (dia. 8m/m) by the X-ray diffraction stress analyzer according to the kind of ceramic powder and different measuring stages. And, for the measurement of the distortions, fifteen specimens of the anterior 8-unit ceramo-metal brige were fabricated and subjected to the 3-D coordinate measuring machine. Variables included the 2 kinds of a ceramic powder and the presence or absence of a splint bar at the cast metal framework. The measuring stages in both were after casting, after degassing and after glazing. The following conclusions were obtained : 1. The residual stress of the alloy showed increasing tendency for the tension by the ceramic fusing, but there was not significance. 2. The tendency of the distortions in the cast metal frameworks were decrease of the width, the anterior displacement and sagging. 3. The amount of the distortions at the degassing stage were greater than that at the ceramic fusing stage. 4. The splint bar was effective to control the distortion only at ceramic fusing stage. 5. The sagging distortion in the Ceramco firing were even through all measuring stages, but in the Vita firing, pronounced at degassing stage.

• 대한치과보철학회지
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• 제43권1호
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• pp.95-104
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• 2005

Statement of problem. Higher stresses at the cervical bone around dental implants have been seen as a primary cause of the bone resorption at the site. Purpose : To determine the possibility of stress reduction by assembly of different abutment and implant in diameters. Material and methods. Abutments of several different diameters assembled on the top of XiVE$^{(R)}$ implants were axisymmetrically modeled for a series of finite element analyses. Abutments of 3.4, 3.8, 4.5, and 5.5 mm diameters were assumed to be sit on implants of the same or bigger diameters. All the abutments with an exception of 3.4mm dia, are technically possible to be assembled on bigger implants. Main consideration was given to the stresses at the cervical cortical bone induced by loads of parallel to the implant axis. Results and conclusions. 1. Higher stresses were observed at the cervical area of all the models of the same diameters of abutment and future. The peak stresses, which were shown to be a function of the fixture diameter, were from 1-1.85MPa. 2. Difference in the diameters of the abutments and the implants actually reduced the cervical bone stresses. 3. Downsizing of the abutment by one step resulted in 0.1MPa (5%) reduction of the stresses. In light of the relatively lower bone stress, however, this amount of stress reduction was decided to be biomechanically insignificant.

• 한국토양환경학회지
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• 제5권2호
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• pp.55-66
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• 2000

본 실험에 사용된 토양으로는 U. S EPA Synthetic Soil Matrix를 선택하였고, 오염된 토양을 만들기 위하여 건조 토양의 무게 백분율로 4.79%에 해당하는 양만큼의 Pyrene을 Dichlomethane에 녹여 고체상태인 Pyrene을 토양에 오염시켰다. 오염된 시료(50$\pm$0.1mg)를 전기적으로 열적처리하는 열반응기는 외경이 20cm, 높이가 30cm인 실린더 형태로서 Pyrex재질로 제작하고 윗부분과 아래 부분은 알루미늄 플랜지로 밀폐시켰다. 내부에는 stainless steel판(3.5cm$\times$13cm$\times$0.00254m, 3.5cm$\times$13cm$\times$0.00254cm, 302 stainless steel shim)과 두개의 전극봉으로 구성되었다. 각각의 토양을 열적처리하기 위한 조건은 최고온도가 45$0^{\circ}C$에 가온율이 $1130^{\circ}C$/s인 경우, 최고온도 $760^{\circ}C$에 가온율이 $950^{\circ}C$/s인 경우 그리고 최고온도가 $977^{\circ}C$ 에 가온율이 $977^{\circ}C$ /s인 경우를 선정하였다. 토양을 열처리한 후 알루미늄 foil funnel과 glass filter paper에서 타르를 포집하였으며, 타르와 잔류토양 시료내의 물질은 Dichlorornethane을 이용하여 추출하였고 이를 HPLC로 측정하였다. 실험결과, 최고온도가 $455^{\circ}C$ 인 경우 Tar Filter에 포집된 Tar색은 White이었으며 대부분의 성분이 Pyrene으로 나타났다. 최고온도가 $760^{\circ}C$ 인 경우는 Tar의 색이 Pink brown이었으며, 약간의 그을음덩어리(Cluster)가 전극관과 Tar Filter의 표면에서 발견되었다. $977^{\circ}C$ 의 경우 Tar색은 Dark brown이었다. Tar성분을 추출하여 HPLC로 분석한 결과, 6개의 Bipyrene의 isomer가 발견되었으며 그 중에서 bacterial cell이나 human cell에 돌연변이를 유발할 수 있는 매우 유해한 성분으로 분류되는 Cyclopenta(cd) pyrene(CPEP)는 온도 조건 $455^{\circ}C$ 에서는 검출되지 않지만 $760^{\circ}C$ 및 $977^{\circ}C$ 에서는 검출되는 특징을 보였다. 그밖에 미미한 양이지만 C14H10과 C15H10이 검출되었다.

• 대한기계학회논문집B
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• 제41권7호
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• pp.445-453
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• 2017

본 연구에서는 RO용 고압 다단 펌프의 수력 부 성능에 대해서 연구를 수행하였다. 수력 부 설계는 크게 임펠러 설계와 레이디얼 디퓨저 설계로 나뉠 수 있다. 임펠러의 자오면 형상 변화에 따른 유동분포와 성능을 수치 해석적으로 연구하였으며, 임펠러 외경, 출구 폭, eye dia 등은 고정시킨 상태에서 반응 표면 기법을 이용하여 허브 및 쉬라우드 자오면 곡선을 변화 시키면서 성능을 최적화하였다. 해석결과 양정에 가장 큰 영향을 미치는 설계 변수는 ${\varepsilon}Ds$로 나타났으며 효율은 허브 입구 길이 및 쉬라우드 곡선이 가장 큰 영향을 주는 것을 알 수 있었다. 자오면 프로파일을 변경한 결과 기준모델(case 25)에 비해 약 0.5% 효율이 개선됨을 확인할 수 있었다.

• 약학회지
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• 제37권2호
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• pp.136-142
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• 1993

To a suspension of 1-cyclopropyl-6,8-difluoro-1,4-dihydro-7-{3,7-diazabicyclo[3.3.0]oct-1(5)-en-3-yl}-4-oxo-3-quinoline carboxylic acid(C1) in sodium hydroxide solution and water is added dropwise with stirring carbon disulfide. [6R-[6$\alpha$, 7$\beta$(Z)]]-7-[[[2-Amino-4-thiazoly)methoxyimino]-acetyl]amino]-3-[[[[7-( 3-carboxy-1-cyclopropyl-6,8-difluoro-1,4-dihydro-4-oxo-7-guinolonyl)-3,7-diazabicyclo[3.3.0]oct-1(5)-en-3-yl]thioxomethyl]thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-en-2-carboxylic acid (DACD) was synthesized from 1-cyclopropyl-6,8-difluoro-1,4-dihydro-7-[7-(mercapto) thioxomethyl-[3,7-dia zabicyclo[3.3.0]oct-1(5)-en-3-yl}]-4-oxo-3-quinoline carboxylic acid disodium salt(C2) and cefotaxime. The invitro activity of novel dual-action cephalosporin, DACD, was compared with the in vitro activities of CENO(cefotaxime 3'-norfloxacin dithiocarbamate), cefotaxime, and norfloxacin against a variety of bacterial species. In vitro activity of DACD was superior to that of norfloxacin against Streptococcus pyogenes. Against Gram-positive and Gram-negative bacteria, its activity was almost equal to that of CENO.

• 한국식생활문화학회지
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• 제25권5호
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• pp.625-632
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• 2010

The purpose of this study was to investigate the appropriate water content in high omega-3 fatty acid Saury nuggets for the desirable texture. The approach was made with adding water and onion at various levels (0~20%). The main ingredients of the nuggets included saury mince, mild pizza cheese, and hydrated textured soy protein concentrate. The formulated products were molded (dia. 4.5, thickness 1.5 cm, 20 g), lightly battered, and flash fried for 4 min. at $160^{\circ}C$, and then frozen until tested. The frozen nuggets were cooked at $165^{\circ}C$ and subjected to sensory evaluations, texture analysis, and water content analysis during warming (0~60 min), as well as assessments of acid, peroxide, and TBA values (during 10 days of storage at $24^{\circ}C$). In the sensory evaluation, preference for texture was highest in the nuggets made with a 15% onion level. The hardness of the nuggets increased with increasing onion level. Moisture content was highest in the nuggets made with a 20% water level. Changes in hardness during warming (0~60 min) of Saury nuggets containing various water and onion levels increased in nuggets made with the 20% water level. The acid, peroxide, and TBA values of the Saury nuggets made with herbs and oriental herbal extracts decreased up to 10 days of storage.

• 한국융합학회논문지
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• 제9권8호
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• pp.117-125
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• 2018

본 연구에서는 각막굴절수술 후 콘택트렌즈 착용 실태, 유통 중인 콘택트렌즈의 베이스커브와 직경을 조사하여, 변형된 각막에 콘택트렌즈를 착용하였을 때 렌즈 움직임과 착용양상을 확인해보고자 하였다. 각막굴절수술 후 16.5%가 콘택트렌즈를 착용한 경험이 있었다. 또한, 콘택트렌즈의 베이스커브는 8.6 mm, 직경은 14.0 mm가 가장 많은 비중을 차지하였다. 각막굴절수술 한 24안의 각막은 편평하였으며, 콘택트렌즈를 착용했을 때 렌즈는 이측과 하측으로 모두 이동하였다. 각막굴절수술 후 콘택트렌즈 착용으로 불편함을 느낄 수 있어 렌즈 착용시 상세한 설명과 한정적인 렌즈의 종류로 정교한 피팅이 필요하며, 콘택트렌즈의 산업과 임상적인 연구에서 융합이 필요할 것이라고 생각된다.

• 한국초지조사료학회지
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• 제8권2호
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• pp.77-84
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• 1988

This experiment was conducted to investigate the morphological and structual characters and the dry weight of plant (DW/pl.) concerned vegetational structure of orchardgrass pastures by the times of year, from 1 year to 7 year previous, 1986 through 1980, alternately. this experiment was carried out on the experimental fields of Yonsei University. The results are summarized as follows: 1. Population density (PD) was extremely decreased by the times of year. 2. Pasture productivity was highest at 3 year old pasture, was lowest at 5 year old pasture and was recovered at 7 year old pasture. 3. Recovery of pasture productivity was followed the increase of dry weight of plant (DW/pl.) and number of tillers per plant (NT/pl.) 4. The population density of 7 year old pasture was 14 plants per square meter. 5. The number of tillers per plant (NT/pl.), dry weight of plant (DW/pl.) plant length (PL), and plant size (PS) was frequently showed the highest values by the times of established year. 6. The stubble diameter (DIA), stubble area (SB), plant size (PS), distance between neibour plant (DIS) and leaf area index (LAI) was increased according to the times of year. 7. The dry weight of plant (DW/pl.) was positively significant correlations with the number of tillers per plant (NT/pl.) all of the established pastures, but the dry weight of a tiller (WT) was tended to increase of correlations with the dry weight of plant (DW/pl.) by the times of year. 8. Differences between morphological and structual characters was recognized according to the times of year.

• 한국수자원학회논문집
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• 제34권5호
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• pp.415-426
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• 2001

재해영향평가제도가 시행된 이후 평가서에는 홍수량 산정 및 개발로 인해 증가된 유출량에 대한 대처방안으로 저류지용량을 산정할 때 임계지속기간의 개념을 도입하여 각종 수문량이 산정된다. 임계지속기간은 수공구조물의 종류, 유역특성과 계획강우의 시간적분포 및 재현기가, 유출모형에 따라 변화한다. 본 연구에서는 저류지 설계시 소요용량을 결정하기 위해 기존 연구에서 제안한 바 있는 저류비의 개념을 이용하여 산정된 저류지용량과 강우지속기간에 따른 저류지용적이 최대가 되는 때의 저류지용적 등을 비교·분석함으로써 저류지 설계시 적정용량을 산정하는 방법을 제안하였다. 추후 유출수문곡선으로부터 최대부하를 야기시키는 계획강우의 임계지속기간을 정하는 문제는 다양한 유출모형과 실적자료를 통한 강우-유출해석과 연계시켜야 할 것으로 판단된다.