• 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.

• 한국환경생태학회지
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• 제29권5호
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• pp.785-790
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• 2015

대면적 개벌의 대안으로서, 대상 개벌은 생산림지의 생태 조건 보전과 임분 재생을 모두 고려하는 작업법이다. 그러나 우리나라에서는 대상 벌채 기법의 적용 및 효율성에 대한 연구를 찾아보기 어렵다. 본 연구는 강원도 삼척에서 2012년부터 2014년까지 소나무림 대상 벌채 (10m, 20m 및 40m) 처리 전 후의 하층식생 반응 및 소나무 재생과 임분 환경 변화와의 상관성을 방형구법을 적용하여 조사 및 분석하였다. 하층식생 피도 및 종다양성은 대상 벌채 넓이에 상관없이 교목 종 및 광선호 종의 확장에 의해 증가하는 경향이었고, 신갈나무, 맑은대쑥 및 산딸기 등의 벌채 후 잔존 교목 및 광선호 종들의 활발한 증가가 관찰되었다. 대상 벌채 구역의 소나무 정착은 수관층 환경 (광량 및 수관열림도) 및 토양나출도와는 정의 상관, 그리고 하층식생 및 임상 목질잔해물의 피도와는 음의 상관을 나타내었다.

• Journal of Pharmaceutical Investigation
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• 제9권2호
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• pp.11-21
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• 1979

It has been reported from our department that a few agents, such as $K_2S_2O_5,\;NaHSO_3,$ nicotinamide have a marked stabilizing effect in vitro on metoclopramide which is relatively unstable compound. In order to study the effect of these stabilizers on the action of metoclopramide in vitro, the fate of this compound combined with $K_2S_2O_5,\;NaHSO_3$ and nicotinamide, respectively, was studied and furthermore, the change of the biological activity of metoclopramide due to these stabilizers was studied by using the isolated stomach strip of rat. The blood concentration of metoclopramide was measured by using Bakke's method at the various time after intravenous injection of the mixed metoclopramide solution with the stabilizers. In order to study the excretion of the drug, rabbits were anesthesized and catheterized into bladder for withdrawal of urine. After intravenous injection of the mixed metoclopramide solution, urine was collected for 5 hours and the conjugated forms of metoclopramide as well as the free form were determined by using Arita's method. In the biological study of the metoclopramide combined with stabilizers, the contractability of the isolated rat stomach strip was observed by using polygraph recorder. The results were following: 1. When metoclopramide was administered with nicotinamide as stabilizer, the blood concentration of the unchanged from and the rate of the clearance of this compound were very similar to that of metoclopramide alone. On the other hand, other stabilizers, $K_2S_2O_5\;and\;NaHSO_3$, brought about 40% decrease in blood concentration of the unchanged form at 15 min after intravenous injection however, the rate of clearance of metoclopramide with $K_2S_2O_5\;or\;NaHSO_3$ was very slow. 2. In the case of urinary excretion, the excretory pattern of the metabolites of metoclopramide with $NaHSO_3$ or nicotinamide was very similar to that of metoclopramide alone. But metodopramide plus $K_2S_2O_5$ group showed the maked depression of excretion for first 1 hour. 3. In composition of metabolites, when metoclopramide was administered with $K_2S_2O_5$ or $NaHSO_3$, the sulfonate conjugation was predominant. But the glucuronic acid conjugation was predominant in metoclopramide plus nicotinamide gronp. 4. In the experiments on the biological activity of the metoclopramide, this compound exhibited the marked contracting effect in isolatd rat stomach strip. Specially, the meetoclopramide combined with $K_2S_2O_5$ showed the strong contraction of the isolated strip, suggesting the potenciating effect of $K_2S_2O_5$ on the action of metoclopramide in the isolated strip.

• 전기화학회지
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• 제2권4호
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• pp.227-231
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• 1999

Carbon paste전극을 백금도금 한 후 이 전극을 사용한 일회용 전류법 glucose센서를 제작하였다. 전극에 시료용액을 가한 후, voltammetry을 이용하여 본 센서의 감응성을 연구하였다. screen printing된 carbon paste전극 표면 위에 전기도금 방법으로 도입된 백금은 센서의 분석성능과 mediator의 전기 화학적 가역성을 크게 향상시켜 준다. 제작된 센서가 $[Fe(CN)_6]^{4-/3-}$에 대한 heterogeneous rate constant는 $1.45\times10^{-2}cm{\cdot}s^{-1}$이며, 이 센서는 적용전위 0.3V vs. Ag/AgCl에서 glucose에 대한 좋은 감응성을 보여주었다. 이 때 glucose에 대한 Michaelis-Menten상수는 24.5mM이다. 일회용 glucose 스트립 센서의 분석성능을 평가하기 위하여 NOVA S.P. Ultra M analyzer와 비교실험을 수행하였다. 이 때 시료용액으로서 $80\~297 mg/dL$ 범위의 glucose를 함유하고 있는 30여 종류의 혈청을 사용하였고, 상관계수는 0.983으로서 정밀도와 정확도가 비교적 우수함을 보여주었다.

• 제어로봇시스템학회논문지
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• 제3권2호
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• pp.179-186
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• 1997

In this paper we suggest a development of surface defect inspection algorithms for cold mill strip. The defects which exist in a surface of cold mill strip have a scattering or singular distribution. This paper consists of preprocessing, feature extraction and defect classification. By preprocessing, the binarized defect image is achieved. In this procedure, Top-hit transform, adaptive thresholding, thinning and noise rejection are used. Especially, Top-hit transform using local min/max operation diminishes the effect of bad lighting. In feature extraction, geometric, moment and co-occurrence matrix features are calculated. For the defect classification, multilayer neural network is used. The proposed algorithm showed 15% error rate.

• Journal of Magnetics
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• 제4권1호
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• pp.5-9
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• 1999

Effect of sulfur segregation on tertiary recrystallization and magnetic induction during final annealing was investigated in a 3% Si-Fe electrical strip containing 6 ppm(LS) and 15 ppm(HS) sulfur. During final annealing, Auger peak height of segregated sulfur on the surface of the strips reached a maximum, and then decreased to low level with increasing annealing time, which is attributed to sulfur segregation and evaporation. The magnetic induction of the thin-gauged 3% Si strip was inversely proportional to the Auger peak height of segregated sulfur on the surface. The overall profile for surface segregation of sulfur and B10 was observed, irrespective of sulfur content in Si-Fe strips, but the peaks of LS strips appeared earlier than those of HS strips. The grain growth rate of the LS strips during final annealing was faster than that of the HS strips, which may be attributed to the pinning effects of segregated sulfur. With increasing final annealing temperature, B10 value increased rapidly and the saturation level in B10 increased.

• 대한소아치과학회지
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• 제32권1호
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• pp.67-74
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• 2005

본 연구의 목적은 타액 분비량, 타액의 완충능력 그리고 타액 내 뮤탄스 연쇄상구균 수를 측정하여 치아 우식경험도와의 상관관계를 분석하기 위하여 시행하였다. 81명의 평균연령 26.1세인 81명의 전북대학교 치과대학생을 대상으로 구강내 우식경험지수를 조사한 후 타액 분비량을 측정하였고, 시판 중인 Dentobuffer Strip 키트와 Dentocult SM-Strip mutans 키트(Orion Diagnostica, Finland)를 사용하여 타액의 완충능력과 뮤탄스 연쇄상구균 수를 평가한 결과, 다음의 결론을 얻었다. 1. 조사 대상자의 평균 DMFT와 DMFS는 6.57과 12.65를 나타냈다. 2. 일반적으로 우식경험지수가 높을수록 타액 분비량이 낮아지는 경향을 보였으나, 이 중 자극성타액 분비량과 DMFT사이에서만 통계적으로 유의한 차이를 나타냈다(P<0.05). 3. 타액의 완충능력과 우식경험도 사이의 관계에서 타액의 PH가 낮아짐에 따라 DMFT와 DMFS는 증가하였으며, 특히 DMFT의 경우 통계적으로 유의한 결과를 보였다(P<0.05). 4. 타액 내 뮤탄스 연쇄상구균의 수가 높을수록 DMFT와 DMFS가 높게 나타났으며 통계적으로 유의한 차이를 나타냈다(p<0.05). 5. 자극성 타액 분비량이 낮을수록, 타액의 완충능력이 낮을수록, 그리고 타액 내 뮤탄스 연쇄상구균 수가 많을수록 더 높은 우식경험도를 나타냈다.

• 한국수학사학회지
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• 제13권2호
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• pp.87-94
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• 2000

This paper investigates history and modern developments concerning spatial decay estimates for solutions in a semi-infinite cylinder or strip, in which model equations are defined with appropriate homogeneous lateral boundary conditions and initial conditions but left end boundary data are assumed. Our aim is to show this Saint-Venant type decay rate dependent critically on the Poincare constant resulting from characterizing variational principles.

• Geomechanics and Engineering
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• 제22권3호
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• pp.197-206
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• 2020

Reutilization of solid waste such as Tire Derived Aggregate (TDA) and mixing it with soft soil for backfill material not only reduces the required volume of backfill soil (i.e., sand-mining procedures; reinforcement), but also preserves the environment from pollution by recycling. TDA is a widely-used material that has a good track record for improving sustainable construction. This paper attempted to investigate the performance of Kaolin-TDA mixtures as a backfill material underneath a strip footing and close to a retaining wall. For this purpose, different types of TDA i.e., powdery, shredded, small-size granular (1-4 mm) and large-size granular (5-8 mm), were mixed with Kaolin at 0, 20, 40, and 60% by weight. Static surcharge load with the rate of 10 kPa per min was applied on the strip footing until the failure of footing happened. The behaviour of samples K80-G (1-4 mm) 20 and K80-G (5-8 mm) 20 were identical to that of pure Kaolin, except that the maximum footing stress had grown by roughly three times (300-310 kPa). Therefore, it can be concluded that the total flexibility of the backfill and shear strength of the strip footing have been increased by adding the TDA. The results indicate that, a significant increase in the failure vertical stress of the footing is observed at the optimum mixture content. In addition, the TDA increases the elasticity behaviour of the backfill.

• 대한전자공학회논문지SD
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• 제41권12호
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• pp.13-19
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• 2004

반도체 또는 평판디스플레이 제조에 있어 노광공정 후의 PR(photo-resist) 제거 공정으로서 기존의 황산기반 용액을 대체하는 고농도 오존 수 생성 기술에 대한 연구를 수행하였다. 세라믹 연면방전구조의 오존발생장치를 개발하여, 0.5［ℓ/min］의 산소 유량에서 최대 12［wt%］이상의 오존가스 농도를 얻었으며, 이를 고농도로 물과 혼합하기 위한 고효율 오존접촉장치를 개발하였다. 오존 수 생성 실험 결과, 오존가스 10［wt%］에서 80［ppm］이상의 오존 수 농도를 달성하였으며, 70［ppm］의 오존 수에서 PR 제거율 147［nm/min］의 양호한 결과를 얻었다.