• 한국터널지하공간학회 논문집
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• 제11권4호
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• pp.419-425
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• 2009

최근에 저토피 및 터널 갱구부에 반개착식 공법을 적용하여 구조적인 안전성과 자연친화성을 높인 사례가 증가하고 있다. 반개착식 공법은 저토피구판에시 원지반을 터널 천단아치에 해당하는 기초까지만 굴착하고 아치형 구조달을 설치하여 복토한 후에 터널하반을 굴착하여 기존 개착공법에서 발생되는 지반 과다절취에 따른 대절토 비탈면 발생과 굴착면 보강에 따른 고비용과 불안정성 증대 문제를 해결할 수 있는 공법이다. 본 논문에서는 저토피 구간에서 반개착식으로 굴착한 Braced Rib Arch의 거동에 대하여 연구하였다. 아치형구조물의 Rib Arch는 지간이 1.8 m인 아치형 강재를 간격재는 목재를 사용하였으며 1:10의 축척으로 4.0 m(폭)$\times$3.3 m(높이)$\times$4.0 m(연장)의 크기를 가진 대형토조에서 실험을 수행하였다. 모형실험결과 아치형 구조물에 작용하는 성토하중은 기존 개착터널에서 사용하는 하부구조물의 폭에 해당하는 상부토체의 크기보다 작은 것으로 나타났다.

• 한국식품영양학회지
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• 제27권4호
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• pp.650-659
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• 2014

The purpose of this study was to analyze Hanwoo usage in restaurants and to develop menus of lean cut Hanwoo. Restaurant served customers Hanwoo menus, with the exception of broiled or roasted meat, mainly to provide various menus to customers (4.14), due to customer needs (3.87) and utilizing stocks (3.59). On the other hand, the reason for not providing Hanwoo menus, with the exception of broiled or roasted meat was manpower shortage (3.63), lack of popularity (3.58), low profit (3.29), preservation of Hanwoos' original flavors (3.28) and complex cooking methods (3.22). Concomitantly, the restaurant owners' intentions to apply new menus with lean cut Hanwoo was 73.4%, showing an interest in developing new menus and recipes using lean cut Hanwoo suitable to the changing owner awareness of customer health and trends. This study has established a standard for developing cooking methods and developed menus according to classified recipes for lean cut Hanwoo, based on the survey of restaurants' current status of using Hanwoo and the owners' opinions. 20 menus using lean cut Hanwoo (rump or shank) were developed by $1^{st}$ and $2^{nd}$ cooking experiments, and in-depth interview of experts-groups. Of these, 12 menus suitable for the restaurant were finally selected based on the results of consumer's evaluation using JARS. Structured recipe flow diagram and recipe instructions were developed for future semi-processed or processing foods. Diverse recipe methods using lean cut Hanwoo were obtained from the study, however aggressive public relations work is required for promoting the developed menus.

• 한국통신학회논문지
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• 제14권4호
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• pp.360-368
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• 1989

본 논문에서는 cut-through 스위칭 방식으로 음성과 데이터를 집적하였을때, 그 성능을 분석하고 패켓 스위칭 방식과 비교하였다. 우선 음성과 데이터 패켓이 네트웍 내의 한 node를 cut-through할 확률을 유도하고, 각각의 네트웍 delay의 Laplace transform을 구했다. 분석결과로 부터 cut-through 스위칭 방식이 패켓 스위칭 방식보다 성능이 우수함을 알 수 있다.

• International Journal of Precision Engineering and Manufacturing
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• 제4권3호
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• pp.62-67
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• 2003

The grinding force generated during the grinding process causes an elastic deformation of the workpiece, grinding wheel, and machine system. Thus, the true depth of cut is always smaller than the apparent depth of cut. This is known as machining elasticity phenomenon. The machining elasticity parameter is defined as a ratio between the true depth of cut and the apparent depth of cut. It is an important factor to understand the material removal mechanism of the grinding process. To increase productivity, the value of this machining elasticity parameter must be large. Therefore, it is essential to know the characteristics of this parameter. The objective of this research is to study the effect of the major grinding conditions, such as table speed, depth of cut, on this parameter experimentally, Through this research, it is found that this parameter value is increasing when the table speed is decreasing or the depth of cut is increasing. Also, this parameter value depends on the grinding mode (up grinding, down grinding).

• 한국가스학회지
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• 제9권2호
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• pp.22-27
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• 2005

본 연구에서는 LNG로부터 냉열을 활용하여 $^{13}CH_4$과 $^{12}CH_4$을 분리하는 초저온 증류 공정에 대한 전산 모사를 분석한 것이다. 사용한 전산 모사 프로그램은 short-cut 방법으로 사용되는 Smoker식과 FUG(Fenske-Underwood-Gilliland) 방법 두가지를 활용하여 실시하였다. 일반적으로 탄소 동위원소 분리에 대한 기술은 많은 방법들이 연구중에 있으며, 특히 초저온 증류 공정에 의한 분리는 많은 장점으로 인해 상업적으로 활용되고 있다.

• Journal of Biosystems Engineering
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• 제34권4호
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• pp.228-233
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• 2009

In order to cut the round bale easily, a roughage cut-feeder for the round bale was developed in this study. This study consists of two parts. One is development of a cutting mechanism and a performance test reported in the previous paper. This is the second part of the study. For the study, recent trend of traditional cutting system was analyzed. Also, cost of the prototype cut-feeder was analyzed and determine the break-even point of farm size was determined by comparing with traditional method using a traditional cutter. A prototype cut-feeder was investigated with the fact that working performance, fiber length and shape of roughage and feeding quality was good. Operating cost of the prototype cut-feeder decreased rapidly with an increase of farm size. Break-even point in terms of farm size was 36 heads for beef and 28 heads for dairy. Also, costs estimated were 118,000 won/head year and 148,000 won/head year, respectively.

• Asian-Australasian Journal of Animal Sciences
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• 제9권6호
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• pp.737-741
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• 1996

Dry matter yield of reed canarygrass was investigated in uncultivated rice paddy in Korea, and an attempt was made to estimate the most economic and efficient cutting frequency and rates of nitrogen (N) fertilization, for increased production of reed canarygrass. Total dry matter yields of reed canarygrass per year were 7.4-15.7, 8.5-16.1, and 7.5-13.4 tons/ha in 3, 4, and 5 cutting frequencies, respectively, and over the N treatments of 0-120 kg N/ha/cut. When cut 3 or 5 times annually, the 2nd cut produced the highest proportion of total yield at 38.4 and 33.0%, respectively, when cut 4 times the 3rd cut was highest (38.3%). The ranges of economic N level, limiting N level and efficiency of dry matter production were 243.3-293.0, 387.2, and 14.6 kg DM/kg N, respectively. These indicators were particularly low for the 5 cutting frequency possibly because of the unusually high temperature in the summer season. The best cutting frequency for the dry matter production of reed canarygrass in 1994 was 3 per year because of the higher efficiency of dry matter production.

• 한국식품저장유통학회지
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• 제23권5호
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• pp.623-630
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• 2016

본 연구는 신선편이 양파의 포장방법 및 저장온도가 신선편이 양파의 선도유지 및 품질에 미치는 영향을 알아보기 위해 저온 저장 중인 양파를 뿌리 및 줄기 부분을 절단하고 껍질을 제거하는 등 최소로 가공한 양파를 준비하였다. 최소가공 한 신선편이 양파는 polyethylene(PE, $50{\mu}m$) 필름에 밀봉 포장하거나 polyethylene/polypropylene(PE/PP, $100{\mu}m$) 필름에 진공 포장하고, $4^{\circ}C$ 및 $10^{\circ}C$에 저장하면서 21일 동안 미생물 분석, 색도, 산도, pH, 포장 내 기체변화, 관능적 품질을 조사하였다. 미생물 분석 결과 총 세균 및 대장균군의 밀도는 포장방법보다는 신선편이 양파의 저장온도에 큰 영향을 받았으며, $10^{\circ}C$보다는 $4^{\circ}C$에 저장했을 때 세균의 밀도가 낮았다. 곰팡이는 PE 필름에 밀봉 포장하여 $10^{\circ}C$에 저장했을 때 저장 13일부터 다른 처리구에 비해 현저히 높은 밀도를 보였다. 그러나 대장균은 모든 처리구에서 조사기간 동안 검출되지 않았다. 신선편이 양파의 표면 색도값($L^*$, $a^*$, $b^*$)은 포장방법이나 저장온도에 따른 차이는 없었으며, 다만 PE/PP에 진공 포장하여 $10^{\circ}C$에 저장 했을 때 저장 5일부터 17일까지 다른 처리구보다 현저히 높은 색차값(${\Delta}E$)을 나타내었다(p<0.05). 신선편이 양파의 산도는 포장방법 및 저장온도에 따른 영향은 없었으며, pH는 PE/PP 필름에 진공 포장하여 $10^{\circ}C$에 저장했을 때 저장시간이 지나면서 점차 증가하는 경향이었다. PE 필름에 신선편이 양파를 밀봉하고 포장 내 기체조성 변화를 조사한 결과 저장온도 간에 현저한 차이를 나타내었으며, $4^{\circ}C$에서 보다 $10^{\circ}C$에서 높은 $CO_2$ 농도와 낮은 $O_2$ 농도를 나타내었다(p<0.05). 신선편이 양파의 외관 품질은 저장시간이 지나면서 점차 낮게 평가되었으며, 특히 저장 13일 이후부터는 포장방법 및 저장온도에 따라 현저한 차이를 보였다(p<0.05). 신선편이 양파의 관능적 품질은 저장온도에 보다 큰 영향을 받았으며, 동일한 저장 온도에서는 PE 필름에 밀봉한 양파보다는 PE/PP 필름에 진공 포장한 신선편이 양파의 품질이 더 양호하였다. 결과를 종합해보면 신선편이 양파를 PE/PP 필름에 진공 포장하고 $4^{\circ}C$에 저장 유통하는 것이 유통기한 연장 및 품질유지에 가장 효과적인 것으로 판단된다.

• 한국초지조사료학회지
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• 제14권4호
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• pp.257-263
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• 1994

The experiment was canied out to investigate the effects of cutting frequencies (3, 4 and 5 cuts per year) in relation to fertilization of mineral nitrogen on crude protein yield and the contents of crude protein and acid detergent fibre in orchardgms(Dacty1is glomerata L.). Tne results are as follows : 1. The content of crude protein increased according to the increase in cutting frequency and showed the highest in the 1st cut in all treatments. At 4 and 5 cutting frequencies per year, the content of crude protein increased in a large extent according to the increased fertilization of mineral nitrogen. However at 3 cutting frequency, the content of cmde protein appeared higher for no application of mineral nitrogen than for the treatments with fertilization. 2. 'Ihe content of acid detergent fibre(ADF) was considerably reduced at 4 and 5 cutting frequencies and in all treatments, the lowest were recorded in the 1st cut or in the last cut. At 3, 4 and 5 cutting frequencies, the highest ADF were shown in the 2nd cut, 3rd cut and 3rd cut respectively. However, the general trend was that the content of ADF was greatly reduced according to increased level of mineral nitrogen fertilization. 3. The yeild of cmde protein was the highest at 5 cutting frequency(l.2 ton DMIha) and it indicated that the yield of cmde protein increased in accordance to the increase in fertilization of mineral nitrogen and cutting frequency. 4. In all treatments, positive correlation(p<0.001) between the yeilds of crude protein and annual dry matter yield appeared. Negative correIation(p

• Preventive Nutrition and Food Science
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• 제17권3호
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• pp.210-216
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• 2012

The use of suitable sanitizers can increase the quality of fresh-cut produce and reduce the risk of foodborne illnesses. The objective of this study was to compare the washing effects of 100 mg/L sodium hypochlorite (SH) and 500 mg/L acidified sodium chlorite (ASC) on the prevention of enzymatic browning and the growth of microbial populations, including aerobic plate counts, E. coli, and coliforms, throughout storage at $4^{\circ}C$ and $10^{\circ}C$. Fresh-cut zucchini, cucumbers, green bell peppers, and root vegetables such as potatoes, sweet potatoes, carrots, and radishes were used. Compared to SH washing, ASC washing significantly (p<0.05) reduced microbial contamination on the fresh-cut produce and prevented browning of fresh-cut potatoes and sweet potatoes during storage. More effective inhibition of aerobic plate counts and coliforms growth was observed on fresh-cut produce treated with ASC during storage at $10^{\circ}C$. Polyphenol oxidase (PPO) activity of fresh-cut potatoes and sweet potatoes was more effectively inhibited after washing with ASC. The use of 500 mg/L ASC can provide effective antimicrobial and anti-browning treatments of fresh-cut produce, including processed root vegetables.