• Journal of Welding and Joining
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• 제20권2호
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• pp.65-70
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• 2002

This study was to evaluate GMA welding characteristics of the A15083-O aluminum alloy according to the shield gas mixing ratio and heat input change. The GMA welding of the base metal was carried out with flour different shield gas mixing ratios(Ar100%+He0%, Ar67%+He33%, Ar50%+He50%, and Ar33%+He67%). Regarding the if1uence on the bead shape of the shield gas mixing ratio and heat input, the bead width was greatest in Ar100%+He0% mixture. But the penetration depth and area were greatest in Ar33%+He67% mixture considering that the lower Ax gas ratio, the higher bead depth and area. Also, dilution was also best in the shield gas mixing ratio. The size and number of deflects were least in Ar33%+He67% mixture. Higher He gas ratio resulted in less deflects detected by the radiographic inspection.

• 펄프종이기술
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• 제34권3호
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• pp.25-31
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• 2002

The purpose of this study was to analyze how the fiber properties and mixing ratio of softwood and hardwood pulp affect on roundness of printed image. Softwood pulp and hardwood pulp were refined to 400 and 600ml CSF by Valley beater and handsheets of 70 g/$m^2$ basis weight were made at different mixing ratios of hardwood and softwood pulp. The roundness, dot area, and shape of the printed dot were measured by Image Analyzer. The depths and shapes of the acridine orange penetration into paper were measured by CLSM. With higher mixing ratio of hardwood pulp, the paper showed higher air-permeability and better formation, especially at lower freeness. The roundness of the printed image became better and the dot size became smaller when the amount of hardwood pulp increased. Penetration depth of acridine orange by CLSM became greater and roundness increased to real circle when the amount of hardwood pulp increased. It was thought that higher mixing ratio of hardwood fibers resulted in efficient penetration by better formation with uniform micro-pore distribution and it increased roundness. It was thought that fiber properties and mixing ratio affected the structure of paper and the shape of the printed dot. This study showed that the measurement of depth of the liquid penetration into paper without destruction and contact was feasible. Moreover, this method showed that the shape of the liquid penetration was measurable.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 춘계 학술발표회
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• pp.123-131
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• 2009

본 연구에서는 2차원 및 3차원 유한요소 해석을 이용하여 심층혼합처리 공법에 의한 연약지반 개량시 개량 심도를 결정 하였고, 그 결과는 다음과 같았다. 1. 2차원 해석 결과는 3차원 해석 결과 보다 약 10% 정도 크게 해석되었다. 2. 연약지반의 치환율이 5%이하 일 때 침하량은 급격히 증가하였다. 3. 심층혼합공법으로 연약지반 개량시 횡방향 간격 3m, 종방향 간격 6m, 그리고 8m의 심도로 개량하는것이 가장 경제적인 것으로 나타났다. 4. 심층혼합공법으로 연약지반 개량시 2차원 유한요소 해석보다 3차원 유한요소 해석으로 결정되어야 한다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2003년도 봄 학술발표회 논문집
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• pp.847-852
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• 2003

The purpose of this paper is to develop the new deep mixing method installed automatic control equipments for the better construction in deep mixing and grouting. Civil, geotechnical, electronic, and communication experts have worked together for a long time for the development of automatic measuring devices using wire and wireless transmitting-receiving set. A series of laboratory and field experiments were carried out to check the reliability and field applicability of this system. New total automatic control system including automatic devices for checking angle, depth and quantity of injected grout was invented from the result of this research.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2006년도 춘계 학술발표회 논문집
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• pp.1155-1158
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• 2006

This paper presents a study on the construction condition and environmental effect of deep soil mixing. Construction condition means the difference in unconfined compressive strength with respect to the depth and location of samples. Environmental effect means alkalinity diffused from soil stabilizer. The experimental results indicate that the unconfined compressive strength vary with respect to the depth, and doesn't show consistency pattern. So, in field application we must decide a mixing ratio enough to satisfy the least unconfined compressive strength. The difference in unconfined compressive strength with respect to the location of samples is negligible. The generation of alkalinity from soil stabilizer is reduced by permeating in non-improved soil and it is expected that the diffusion of alkalinity has no environmental effect on soil and ground water.

• 한국해양학회지
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• 제27권2호
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• pp.154-163
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• 1992

박테리아의 개체수와 생산량의 분포률, 그리고 하구 혼합 (estuarine mixing)이 이들 분포에 미치는 영향을 조사하기 위해, 1990년 10월부터 1991년 8월까지 만경강 및 동진강 하구의 유광대에서 박테리아의 개체수, 생산량, 수온 및 염분도를 3번 조사 하였다. 제한된 조사에도 불구하고 조사기간에 나타난 박테리아의 개체수와 생산량은 넓은 범위의 값을 보였다. 각각 0.4-5.8$\times$10/SUP 9/ 1/SUP -1/와 0.1-22.2 ug C /SUP -1/ d/SUP -1/이었다. 이는 박테리아의 성장이, 하구에서 매우 유동적임을 나타냈다. 흥미롭게도 박테리아의 개체수는 대부분의 수임이 얕은 정점의 표면 아래에서 증가하 였으나, 박테리아의 생산량은 뚜렷이 감소하였다. 이러한 현상은 하구 혼합에 의해서 설명될 수 있을 것으로 판단되며, mixing diagrams의 분석은 하구 혼합이 박테리아 개 체수와 생산량을 conservative하게 혼합하기도 하나, 박테리아 개체수를 증가시키며, 생산량을 감소시키는 작용을 하였으며를 보여주었다. 이것은 하구 혼합의 역할이 박테 리아의 개체수와 생산량의 분포에 따라서 하구에서의 생지화학적 순환에 있어서 중요 함을 제시하였다.

• 한국환경복원기술학회지
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• 제18권1호
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• pp.153-163
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• 2015

The study was conducted to develop ecological restoration method of damaged area in DMZ vicinities. As the material for the ecological restoration, forest soil and trees waste have been used. Forest soils were collected for experiments in Yanggu, Gangwon Province. Effect of ecological restoration was analyzed through germination experiment. Germination experiment was performed using 12 kinds of woody and herbaceous seeds. Woody and herbaceous seed germination in test pot was relatively evenly. Mixed material consisting of forest soil and trees waste seemed a possibility as the material for the restoration. The effects on seed germination were higher in the case of mixing more than 70% by volume ratio of local resources. Total number germinated individuals were different depending on the mixing ratio of soil sampling depth. Individual plants showed different trends depending on the experimental combination. Results of the woody seed germination were affected only in the soil sampling depth. Seed germination of herbaceous received a combined effect on soil sampling depth and mixing ratio.

• 한국해양학회지
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• 제6권2호
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• pp.85-91
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• 1971

The origin of the Tsushima Current water was investigated with a discussion on the western North Pacific Central Water. The Tsushima Current water is formed by the mixing of the Kuroshio surface water and the East China Sea water. The area where the mixing takes place remarkably is found to be the marginal region of the continental shelf of the East China Sea at the depth from 100 to 200 meters.

• 한국지반신소재학회논문집
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• 제19권1호
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• pp.35-44
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• 2020

연약지반 개량 공법 중 심층혼합공법에 대한 설계 기법으로는 복합지반으로 해석하는 방법과 말뚝지반으로 해석하는 방법이 있다. 그러나 이러한 해석에 대한 비교 연구는 부족한 실정으로 설계 시 해석 기준을 명확하게 정의 내리는 것에 어려움이 있다. 본 연구에서는 2차원 및 3차원 해석을 통해 성토 높이와 연약지반의 심도, 보강구간의 치환율을 변화시키며 각 조건별로 복합지반과 말뚝지반을 가정하여 해석하였다. 그 결과 최저 개량 심도는 3차원 해석에 비해 2차원 해석 결과가 6.85~9.08% 더 깊은 결과를 도출하였다. 또한 말뚝지반 해석의 경우 복합지반 해석에 비해 개량 심도는 12.22~14.45% 더 깊은 것을 확인하였다. 이 결과를 통하여 보다 정확한 설계를 위해서는 2차원 해석보다는 3차원 해석을 실시해야 하고, 경제적인 설계를 위해서는 복합지반으로 해석해야 하며, 안정적인 설계를 위해서는 말뚝지반 해석을 실시해야 된다고 판단된다.

• 한국분무공학회지
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• 제4권3호
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• pp.32-41
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• 1999

In this research, internal-mixing twin-fluid atomizer using sonic energy is designed and manufactured. We are trying to intimate high efficiency twin-fluid atomizer to obtain good liquid atomization in the low pressure region. Define of geometric form of atomizer, characteristics of spray is influenced by position, depth and height variation of cavity resonator, variation of sound intensity and resonant sound frequency with liquid flow rate. The liquid atomization is promoted by multi-stage disintegration of mixing flow of gas with liquid and the optimum condition of position and depth of cavity resonator according to sonic energy is obtained from the condition at a=2.5mm and L=2mm. The velocity distribution of droplets shows negative value due to recirculation region at the center of axial, and as the radial direction distance is far, the velocity distribution of droplets decrease slowly after having a maximum value. However velocity and SMD show nearly uniform distribution at the down stream and as result compared to Nukiyama and Tanasawa's equation. atomization of mixing flow with air and liquid dispersing from the outlet of the nozzle is promoted by the effect of collision at the cavity resonator.