• Journal of Biosystems Engineering
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• 제34권4호
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• pp.211-219
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• 2009

In the process of oyster mushroom production, loading work of culture medium needs the most intensive labor power and cost. Therefore, the development of culture medium loading machine causes to reduce the manpower and cost. The main objectives of this study are identify cultivating environment, physical properties of culture medium and to make an element design of culture medium loading machine. The results are summarized as follows: 1. The moisture content and density of popularly used culture medium were 70%(w.b), $26\;kg/m^3$, respectively. 2. Pressure of the blower increased as the impeller speed increased, and the opening ratio of pressure controller decreased. 3. Recommendable c1earance(${\delta}$) between an impeller plate and a blower case was 25 mm at an impeller speed of 3183 rpm 4. Discharge device of type B with a hopper and suit was better than type A with a hopper.

• 응용통계연구
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• 제18권1호
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• pp.211-227
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• 2005

현재 통계학과의 수가 급격히 감소하고 있으며 우수한 학생들의 유치가 매우 어려워지는 상황에서 본 연구에서는 통계학과의 발전방향에 대해 다양한 관점에서 연구해 보았다. 특히 외환부족 사태 이후 교직에 대한 선호도가 높아지고 또 7차 교육과정에서 통계 교육이 강화되는 시점에서 통계학에 대한 교직과정을 확대하는 방안 또한 알아보았다. 어느 하나 쉬운 것이 없지만 모두의 다양한 노력이 전제되어야만 더 나은 미래를 만들어 갈 수 있을 것이다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제41회 하계 정기 학술대회 초록집
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• pp.211-211
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• 2011

Nanostructures, with a diversity of shapes, built on substrates have been developed within many research areas. Lithography is one powerful, but complex, technique to make structures at the nanometer scale, such as platinum nanowires for studying CO catalytic reactions [1], or aluminum nanodisks for studying the plasmon effect [2]. In this work, we approach a facile method to construct nanostructures using noble metals on a titania thin film by using self-assembled structures as a pattern. Here, a large-scale silica monolayer is transferred to the titania thin film substrates using a Langmuir-Blodgett trough, followed by the deposition of a thin transition metal layer. Owing to the hexagonal close-packed structure of the silica monolayer, we would obtain a metal nanostructure that includes separated metallic triangles (islands) after removing the patterning silica beads. This nanostructure can be employed to investigate the role of metal-oxide interfaces in CO catalytic reactions by changing the patterning silica particles with different sizes or by replacing the oxide support. The morphology and chemical composition of the structure can be characterized by scanning electron microscopy, atomic force microscopy and X-ray photoelectron spectroscopy. In addition, we modify these islands to a connected island structure by reducing the silica size of the patterning monolayer, which is utilized to generating hot electron flow based on the localized surface plasmon resonance effect of the metal nanostructures.

• 한국식생활문화학회지
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• 제26권3호
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• pp.211-219
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• 2011

To examine the key success factors for long-lasting restaurants, we visited 10 restaurants with 30 or more than 30 years of tradition, located in Seoul and Gyeonggi-do districts, to research these restaurant menus and customer characteristics by observation and interview. The results were analyzed using descriptive statistics. The outstanding feature noted was that each and every restaurant had its own simple and specialized menu. We found that this feature created a virtuous circle that reinforced itself through a positive feedback loop. The simple and specialized menu increased both the cooking efficiency and food quality while it reduced both food and labor costs, this enabled the customers to eat at an affordable price and have generous servings. This lead to customer satisfaction and revisits to the restaurant, which triggered word-of-mouth referral and expansion of their customer base. This in turn created higher operating profit margins that could be reinvested in the business. The secret recipes for cooking, invented by their founders, were passed on from generation to generation. Their customer base included customers of all ages from children to senior people. And their regular customers consisted of neighboring office workers and families traveling from a long distance. We hope that our findings on long-lasting restaurants, especially of the virtuous cycle created due to the simple and specialized menus with secret recipes, will contribute to the development of Korean style long-lasting restaurant model.

• 천문학회지
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• 제37권4호
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• pp.211-216
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• 2004

We present the results of an H I aperture synthesis mosaic of the Large Magellanic Cloud (LMC), made by combining data from 1344 separate pointing centers using the Australia Telescope Compact' Array (ATCA) and the Parkes multibeam receiver. The resolution of the mosaiced images is 50" (<15 pc, using a distance to the LMC of 55kpc). This mosaic, with a spatial resolution .15 times higher than that which had been previously obtained, emphasises the turbulent and fractal structure of the ISM on the small scale, resulting from the dynamical feedback of the star formation processes with the ISM. We also have done a widefield panoramic survey of H$\alpha$ emission from the Magellanic Clouds with an imager mounted on the 16-inch telescope at Siding Spring Observatory. This survey produced H$\alpha$ images which are equal to the ATCA survey in area coverage and resolution. This survey allows us to produce a continuum-subtracted image of the entire LMC. In contrast with its appearance in the H$\alpha$ image, the LMC is remarkably symmetric in H I on the largest scales, with the bulk of the H I residing in a disk of diameter 8. $^{\circ}4$ (7.3 kpc) and a spiral structure is clearly seen. The structure of the neutral atomic ISM in the LMC is dominated by H I filaments combined with numerous shells and holes.

• 한국세라믹학회지
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• 제46권2호
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• pp.211-218
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• 2009

For the Y5V characteristic MLCC which is very prone to crack, it is important to to find out the basic cause of the crack. After finding out the crack origin, the materials and processes should be developed to remove the crack. The microstructures of the cracks were investigated using the fractographic method for the various types of cracks such as an exterior crack, a cyclic thermal shock crack, and an piezo-electric crack. It was found out that the crack origin was the pore at the end of the Ni inner electrode after bake-out. Even though the three dimensional crack shapes were different, the crack origins were seemed to be similar. The exterior crack could grow from the origin with the aids of residual and applied stress. FEM (finite element method) analysis was used to calculate the stress distribution of residual and applied stress. And the concept of fracture mechanics was applied for the explanation of the crack initiation and propagation from the stresses concentration.

• 디지털융복합연구
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• 제15권9호
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• pp.211-221
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• 2017

반도체 산업은 임베디드 소프트웨어를 통해 운영 통제되는 자동화설비를 통해 첨단상품을 생산한다. 반도체를 생산하는 로봇과 각종 설비의 임베디드 소프트웨어 유지보수는 제품의 품질과 신뢰성 제고를 위한 필수적인 과정으로 반도체 장비의 라이프 사이클을 고려할 때 상당히 높은 비중을 차지하는 활동영역이다. 그러나 이 분야에 대한 학술적 관심사는 그리 높지 않는데, 본 연구에서는 반도체 웨이퍼 생산장비를 구동하는 소프트웨어 관련 문제로 보고된 사건을 대상으로 502개의 데이터를 무작위 추출방식으로 수집하여 임베디드 소프트웨어의 유지보수 노력에 영향을 미치는 요인들을 분석해 보았다. 결론으로 실무적인 시사점도 제시하였다.

• Journal of Electrochemical Science and Technology
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• 제2권4호
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• pp.211-215
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• 2011

Flexible sheets consisting of acrylonitrile-butadiene rubber (NBR) and carbon nanotube (CNT) are newly prepared varying the composition (CNT 20-25 wt.%) for use as a current collector of supercapacitor electrodes. The as-prepared CNT/NBR is electrodeposited with aniline using potentiodynamic cyclic voltammetry to yield a polyaniline (PANI)/CNT/NBR composite electrode. It is confirmed that the electrical conductivity of CNT/NBR current collector can be enhanced as the content of CNT increases. Cyclic voltammetry result shows that the sample of PANI/CNT(25 wt.%)/NBR composite achieves a maximum specific capacitance ($134.9\;F\;g^{-1}$) at $5\;mV\;s^{-1}$. Such supercapacitor application is possibly originated from the synergistic effects consisting of higher polarity of nitrile groups in NBR, conducting pathway of CNT, and electroactive property of PANI.

• 한국정보전자통신기술학회논문지
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• 제5권4호
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• pp.211-215
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• 2012

대형의료기기는 환자 진단과 치료 행위에 있어서 매우 중요한 기기이다. 이런 대형의료기기를 사용하여 환자를 진단 또는 치료할 때 의료기기의 회로 내에서 갑작스런 전류의 변화는 회로의 단락 등 매우 심각한 문제를 일으킨다. 특히 회로 내에서 전류변환기에 큰 부하가 걸리게 한다. 이것으로 인해 변환기는 포화에 이르게 되는데 이것은 철심코일 인턱터의 magnetic curve에 기인한다. 이와 같이 변환기가 saturate에 이르게 되면 1차 측과 2차 측의 변환 비율이 깨지게 되고 회로가 단락되는 문제가 발생하게 된다. 이 논문 에서는 대형의료기기에 사용되는 current 변환기의 입력 측에 갑작스런 큰 전류 변화가 발생 했을 때 일어나는 그에 따른 포화 상태와 그의 2차 측 전류의 변화를 simulation 해본다.

• Interaction and multiscale mechanics
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• 제6권2호
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• pp.211-235
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• 2013

An incompressible smoothed particle hydrodynamics (ISPH) method based on the incremental pressure projection method is developed in this study. The Rayleigh-B$\acute{e}$nard convection in a square enclosure is used as a validation case and the results obtained by the proposed ISPH model are compared to the benchmark solutions. The comparison shows that the established ISPH method has a good performance in terms of accuracy. Subsequently, the proposed ISPH method is employed to simulate natural convection from a heated cylinder in a square enclosure. It shows that the predictions obtained by the ISPH method are in good agreements with the results obtained by previous studies using alternative numerical methods. A rotating and heated cylinder is also considered to study the effect of the rotation on the heat transfer process in the enclosure space. The numerical results show that for a square enclosure at, the addition of kinetic energy in the form of rotation does not enhance the heat transfer process. The method is also applied to simulate forced convection from a circular cylinder in an unbounded uniform flow. In terms of results, it turns out that the proposed ISPH model is capable to simulate heat transfer problems with the complex and moving boundaries.