• 한국지반신소재학회논문집
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• 제21권4호
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• pp.21-29
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• 2022

주방식 공법(room-and-pillar method) 또는 격자형 지하공간은 굴착부를 일정한 간격으로 직교하도록 굴착하여 자연 암반을 구조체로 활용하여 공간을 형성해 나가는 공법을 말한다. 이러한 굴착은 굴착 방향과 순서에 따라 최대 변위가 발생하는 굴착 단계와 크기가 다르게 나타날 수 있다. 본 연구에서는 격자형 굴착공정의 최적 설계를 위하여 숏크리트 및 록볼트 등 지보재가 설치되는 것을 고려하여 특정 지반조건에서의 격자형 지하공간 설계 및 시공 시 안정성과 시공성을 해석적으로 검토하였다. 해석적 방법을 사용하여 지반조건을 설정하고 일정 상재하중 하에서 굴착단계와 시공 종류별로 암주 응력과 천단 변위를 확인하였다. 공간의 높이는 8m로 일반 사무실 크기보다 높게 설정하여 장비나 플랜트 시설을 감안하여 검토되었다. 또한, 숏크리트와 록볼트를 고려하여 지보재 설치에 따른 변위 제어의 정도를 검토하였다.

• JSTS:Journal of Semiconductor Technology and Science
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• 제7권3호
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• pp.161-165
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• 2007

In this paper, mesoporous Pt on micro pillars Pt electrode is newly designed, fabricated, and characterized on silicon substrate for non-enzymatic electrochemical sensor micro-chip integrated with CMOS readout circuitry. The fabricated micro/nano Pt electrode has cylindrical hexangular arrayed nano Pt pores with a diameter of 3.2 nm which is formed on top of the micro pillars Pt electrode with approximately $6{\mu}m$ in diameter, $6{\mu}m$ in space, and $50{\mu}m$ in height. The measured current responses of the fabricated plane Pt, mesoporous Pt, and mesoporous Pt on the micro pillar Pt electrodes are approximately $9.9nA/mm^2,\;6.72{\mu}A/mm^2,\;and\;7.67{\mu}A/mm^2$ in 10mM glucose solution with 0.1M phosphate buffered saline (PBS) solution, respectively. In addition, the measured current responses of the fabricated plane Pt, mesoporous Pt, and mesoporous Pt on the micro pillar Pt electrodes are approximately $0.15{\mu}A/mm^2,\;0.56{\mu}A/mm^2,\;and\;0.74{\mu}A/mm^2$ in 0.1mM ascorbic acid (AA) solution with 0.1M phosphate buffered saline (PBS) solution, respectively. This experimental results show that the proposed micro/nano Pt electrode is highly sensitive and promising for CMOS integrated non-enzymatic electrochemical sensor applications. Since the micro-pillar Pt electrode can also be utilized with a micro-fluidic mixer in the sensor chip, the sensor chip can be much smaller, cheaper, and easier to be fabricated.

• 터널과지하공간
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• 제24권6호
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• pp.464-472
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• 2014

환기제어 시설을 설치하지 않고 모든 공간을 개방한 형태의 대단면 주방식 채굴 작업장에 설치하는 국부선풍기의 운전에 따른 기류유동형태는 재순환을 포함하고 있어 복잡하고 정량화가 어렵고 환기효율 또한 매우 낮은 편이다. 본 논문에서는 국부선풍기의 운전에 따라 하류편의 기류 운동에너지 증가 및 정압강하 현상인 벤츄리(venturi) 효과로 인접갱도로부터 기류가 유입되어 기류 유동방향으로 환기량이 증가하는 현상을 선풍기 종류 및 설치방법 별로 CFD분석하였다. 분석대상 선풍기는 축류선풍기 1종류 및 프로펠러 선풍기 2종류이며 축류선풍기 중심점 설치 위치를 1.0, 1.5, 2.0m로 변경함에 따른 벤츄리 효과의 차이를 분석하였다. 연구결과는 공기질 개선을 통한 작업환경 관리를 위한 국부 환기의 경제성 및 효율성을 제고하는데 기여할 것으로 기대된다.

• ETRI Journal
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• 제35권4호
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• pp.625-631
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• 2013

For the formation of solder bumps with a fine pitch of 130 ${\mu}m$ on a printed circuit board substrate, low-volume solder on pad (LVSoP) technology using a maskless method is developed for SAC305 solder with a high melting temperature of $220^{\circ}C$. The solder bump maker (SBM) paste and its process are quantitatively optimized to obtain a uniform solder bump height, which is almost equal to the height of the solder resist. For an understanding of chemorheological phenomena of SBM paste, differential scanning calorimetry, viscosity measurement, and physical flowing of SBM paste are precisely characterized and observed during LVSoP processing. The average height of the solder bumps and their maximum and minimum values are 14.7 ${\mu}m$, 18.3 ${\mu}m$, and 12.0 ${\mu}m$, respectively. It is expected that maskless LVSoP technology can be effectively used for a fine-pitch interconnection of a Cu pillar in the semiconductor packaging field.

• 대한기계학회논문집A
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• 제36권8호
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• pp.929-934
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• 2012

본 연구에서는 레이저 TWB로 용접된 이종재료의 동적 특성에 대한 해석이 수행되었다. 해석프로그램은 Hyper works 10.0으로 Solver는 LS-DYNA v.971, 모델링 요소는 2D-Shell, 요소 수는 35,641개, 노드 수는 36,561개이다. 충격속도는 10 km/h이다. 상 하부의 용접선 높이에 따르는 영향을 연구하기 위하여, 하부의 길이를 300 mm와 400 mm로 하였다. 얻어진 결론은 다음과 같다. 길이 300 mm인 하부 재료 SPFC980의 변형은 가장 작고, 충돌 흡수 에너지는 가장 크다. 하부 냉연강 기준으로 TWB의 위치가 짧을수록 성능이 우수하게 나타났다. 즉, 상대적으로 상부 고강도강인 SABC1470 재료가 차지하는 비율에 따라 성능이 좌우되었다. 하부 재료 SPFH590은 큰 변형이 나타났고, 충돌성능은 SPFC980보다 현저히 떨어졌다. 따라서 충돌 성능 해석 결과에서 하부 재료 SPFC980인 길이 300 mm가 가장 우수한 것으로 나타났다.

• 산업공학
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• 제21권1호
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• pp.43-50
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• 2008

Understanding consumers' latent desires for product form has now become a critical issue in product design. Accordingly, product development processes is rapidly changing from product-oriented development to user-centered development. Driver visibility is considered as an important element of driving posture packaging in automobile interior design. This study presents a systematic process for driver visibility analysis approached from affective engineering method that provides design variable selection and screening with respect to the image/impression element of the human visibility. Also, the analysis of front visibility, often called the feeling of "openness", in motor vehicle interior design, is selected and practiced a case study using the systematic process proposed in this study. Twenty six participants evaluated the feeling of openness for thirty motor vehicles following the perceived scale of affective design factors. The results showed that variables such as the height of head lining, the height of cluster housing, the gradient of windshield and the volume of A-pillar were the critical design variables which affect the feeling of openness in a motor vehicle.

• 건축역사연구
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• 제6권3호
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• pp.9-22
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• 1997

The Wooden Stupa of Hwangnyongsa Temple, existed from Shilla to Koryo Dynasty, is recognized as a typical model of the Korean wooden stupa. The related records on this stupa are found in some historical documents including The Chronicles of the Three States ${\ulcorner}$三國史記${\lrcorner}$. This study, through the interpretation of these documents, attempts to discuss and analyse design and structural methods of the stupa, viz., i) the relationship with both Chinese and Japanese wooden stupa, ii) the height, iii) each floor's linking methods, iv) the 'Noban' (Basement of the upper part), v) structure of the 'Simju' (Central pillar) and vi) the stairs and the handrails. The results of this study would be hopefully used for the further researches as well as the restoration of this precious architectural asset.

• 한국컴퓨터정보학회논문지
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• 제23권9호
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• pp.97-105
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• 2018

The purpose of this study was to analyze the measurement data of 13 ~ 18 year old male students and to characterize the body shape of the lower body, Through this, I tried to provide basic data for the production of pants for adolescent men's students. As a result of analyzing the body shape factor of the lower half, two factors were classified. 'Vertical factor' of the lower body composed of the circumference, thickness, and width, and the 'horizontal factor' of the lower body composed of the length and height. The body shape of the lower half was classified into four categories according to the circumference and length of the lower half of the male students, such as 'short bird legs', 'long crane legs', 'short pillar' and 'long pillar'. In the study of Hong Eun-hee (2005), body type was classified according to horizontal factor and vertical factor like this study. By age, boys aged 13 to 14 can see that the lower body is thin and short, the lower body is thin and long body is 15-16 years old, and the lower body is relatively thick and long body is 17-18 years old. As the age increases, the growth in the vertical direction occurs first and the growth in the horizontal direction occurs. It is thought that it is necessary to set a different amount of allowance for setting the length and the circumference according to the age of the youth. When the age is young, the amount of allowance in the circumferential direction should be increased, and the amount of allowance in the longitudinal direction after 15 years of age should be increased more than other age groups.

• 설비공학논문집
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• 제22권2호
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• pp.64-69
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• 2010

We investigated the variation in contact angle of a nano-sized water droplet on a nano stripe-patterned surface using molecular dynamics simulation. By changing the height and width of the stripe pillar, and the gap width of the stripes, we observed the contact angle of water droplet in equilibrium. When the surface energies were 0.1 and 0.3 kcal/mol, the calculated contact angles were in good agreement with the Cassie and Baxter equation. However, when the surface energy is 0.5 kcal/mol, the contact angles are observed to be perturbed along the Cassie and Baxter equation.

• 대한인간공학회지
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• 제25권3호
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• pp.25-32
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• 2006

As national income increases, consumers began to place a great deal of weight on products or quality of their life. They would like to have products which are more convenient to use and could meet their emotional desire in addition to its basic functional requirements. An automobile is one of the transportation system for human beings and the factor such as safety or environmentaly-friendly is regarded as important things resulting from it's popularization. In fact, domestic design technology leaves much to be desired compared with excellent manufacturing techniques. For this reason, some problems, like lowering of usage, could be caused by introducing technological data as it is from overseas. A survey of domestic car users has found that the most preferred condition (step height) is 460~495cm when they get in and out of their car. Men use their visual information and then get in the car, taking motion fit for each condition when automobile condition is changed. In other words, men get in cars actively within the range of conditions used for this study. These results were found from a motion study, when getting in a car, and checking the possibility of getting injury in accordance with the change of condition as well.