• 한국초지조사료학회지
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• 제10권3호
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• pp.158-163
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• 1990

This experiment was to study the effect of pure mineral nitrogen fertilizing on seasonal distribution of dry matter yield and the advisable mineral nitrogen amounts on grassland. The results were as follows: 1. With longer regrowth periods the absolute dry matter yields and the nitrogen-efficiences due to nitrogen fertilizing increased substantially, whereas the quality declined at the relatively lesser cutting frequencies. 2. The first cut at 3-cut regimes, the first and fourth cut at 4-cut regimes, and the second and last cut at 5-and 6-cut regimes showed the highest nitrogen-efficiency, respectively. 3. By the sigmaformed process of production curve the most efficient mineral N-dressing rate per ha and cut was calculated: 42-56kg N on the 3-cut areas, 39-55kg N on the 4-cut areas, 38-47kg N on the 5-cut areas and 35-48kg N/ha/cut on the &cut areas. 4. In dependence on site and kind of calculation the economical borders were reached with the following dressings of mineral N/ha/cut: 90-100kg on the 3-cut areas, 70-100kg on the 4-cut areas and 50- 90kg on the 5-and 6-cut areas.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2017년도 추계학술논문요약집
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• pp.189-190
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• 2017

For the concept design of the device, a tool was made to test the simulated fuel rods and cutting force and the cutting force was measured. When 2-CUT and 3-CUT modules were used, the maximum force in 2-CUT at 12.5 mm/s speed change was $197.5kg_f$ and the maximum force at 3-CUT was $363.2kg_f$. The change of force in 2-CUT rapidly increases from about 1 second, and you can see that there are increase and decrease of the force change from about 5 seconds to 18 seconds, and it was rapidly decreased and the cut was made. The force change in 3-CUT has higher force at about 5 seconds later than 2-CUT at the speed of 12.5 mm/s, and you can see that it has the same tendency afterwards. If you search for the force at adequate speed from this cutting force test, 2-CUT module requires less slitting force than 3-CUT module, and the cutting time for 250 mm at 12.5 mm/s was 21 seconds, which can cut 4 m fuel rod in 5 minutes. But, there are cases of not completely slitting with 2-CUT module, so it is necessary to supplement this in the future through experiments.

• 대한산업공학회지
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• 제19권3호
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• pp.51-57
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• 1993

This paper develops 0($n^3$) algorithm to construct a cut-tree generated by Gomory-Hu algorithm. The algorithm only requires node sets defined by the minimal cut in each of the (n-1) maximal flow determinations. Merging computerized facility layout procedure that uses cut-tree concept to generate design skeletons with our algorithm requires less storage space than merging it with Gomory-Hu algorithm. Also, the cut-tree can easily be modified when the (n-1) minimal cut-sets are updated due to changes on arc capacities.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 춘계학술대회 논문집 반도체 재료 센서 박막재료 전자세라믹스
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• pp.116-120
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• 2004

In this paper, we proposed a method to shift the resonant frequency by applying the electric field to microstrip patch antenna using piezoelectric substrates. We fabricated microstrip patch antenna using Y-cut LiNbO3, Quartz and FR-4 substrates. We designed and simulated the microstrip antennas by Ensemble V 7.0 of the simulation too1. We observed the resonant frequency by DC applied electric field in a microstrip patch antenna. When the electric field was 300 V/mm, the resonant frequency agile of Y-cut LiNbO3 microstrip patch antennas were 29 MHz. When the electric field was 400 V/mm, the frequency agile of X-cut, Y-cut and Z-cut quartz microstrip patch antennas were 55.2 MHz, 34.2 MHz and 28.0 MHz, respectively. However, when the electric field was 400 V/mm, the resonant frequency of FR-4 microstrip patch antenna does not changed. It was shown that the resonant frequency agile of Y-cut and Z-cut quartz microstrip patch antennas are due to piezoelectric phenomenon not to be permittivity.

• 설비공학논문집
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• 제4권2호
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• pp.116-122
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• 1992

The purpose of this paper is to determine the cut off flowrate regions of the overflow valve in using L.P gas vassels. The experimental methods were employed to measure the cut off flowrate in the state of constant pressure by using the $N_2$ gas. 1) To determine the optimum cut off flowrate regions, Hose length are required 0.5 meters. 2) Cut off fowrate regions about the each pressure can be suggested as follows. A) Cut off flowrate rigions are $2.0-4.0m^3/hr$ at the pressure of the $1Kg_f/cm^2$. B) Cut off flowrate rigions are$7.0-10.0m^3/hr$ at the pressure of the $10Kg_f/cm^2$.

• 한국환경복원기술학회지
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• 제11권5호
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• pp.92-103
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• 2008

Development of new approaches to achieve naturally good ecological potential of forest road cut-slope by making the best use of advantages of gabion systems with vegetation base materials to prevent slope failure and erosion, in the area with highly erodible soil. As a result on the type analysis of gabion systems already installed in road cut-slopes, gabion systems were generally established to prevent slope failure. Existing gabion systems can be divided into monolithic and modular system and can be divided into ten subtypes according to the purpose of establishment and combination of other measures. As a result on the monitoring of erosion amount from forest road cut-slopes in the test applications, the order of erosion amount from largest to smallest is as follows : the curved road cut-slope site where normal gabion system was established ($7,911cm^3$); the control site ($7,632cm^3$); the straight road cut-slope site where normal gabion system was established ($7,301cm^3$); the curved road cut-slope site where the new gabion system was established ($5,684cm^3$); and the straight road cut-slope site where the new gabion system ($5,325cm^3$). Therefore, the result shows that the new gabion system is more effective than the normal gabion system to reduce erosion amount from forest ! road cut-slopes. During the study period, vegetation coverages of the straight and curved road cut-slope site where the new gabion system was established were about 45% and about 36%, so average vegetation coverage of the sites where the new gabion systems was established was higher than the sites where the normal gabion systems was established. Therefore, it was concluded that the new gabion system can be more effective for cut-slope revegetation.

• 아시안잔디학회지
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• 제7권2_3호
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• pp.121-127
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• 1993

This experiment was carried out to compare the varietal differences of dry matter production in rend canarygrass. The varieties examined were Common, Venture, Castor, Palaton and Venture. Reed canarygrass was harvested three times annually, 1st cut(1O, May), 2nd cut(31, July), and 3rd cut(10, Oct.), respectively. The results were summarized as follows ; 1. Dry matter yield were not significant difference between varieties and for the interaction of variety$\times$cut. But, there was significant difference between cuts. 2. There was not significant difference in dry matter yield between the first cut and second cut. But, the dry matter yield of the third cut was poor than the other two cuts. Thus, the average dry matter yield of varieties were 806.1 kg, 730.8kg and 495.8kg /l0a in the first, second and third cut, respectively. 3. In Venture and Palaton, the percentage of dry matter distribution in spring was higher than that of other varieties. In Common, Castor and Vantage, they were not significantly different between the percentage of dry matter distribution in each cut. Above the results suggested that the first group of varieties(Venture and Palaton) were suited to meadow and last group of varieties(Common, Castor and Vantage) were suited to pasture. 4. Average total dry matter yield of varieties was 2,032kg /l0a/yr,(ranged from 1,922kg to 2,180 kg /l0a /yr.)

• 지질공학
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• 제20권2호
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• pp.147-153
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• 2010

투수성이 낮은 매질로 설치되는 차수벽(Cut-off wall)은 댐 지역 비상여수로 터널 지역에서 지하수의 흐름을 차단하기 위한 기능을 갖는다. 임하댐의 3개 비상여수로 터널 입구부에 차수벽 설치시 지하수 유입의 차단 효과를 평가하기 위하여 MODFLOW 모델링을 활용하였다. 규모와 설치 방향 등을 고려하여 3가지 차수벽 설치 방안이 검토되었는데, 모델링을 통하여 추정된 비상여수로 터널내로 유입되는 지하수량은 약 64.26~65.49 $m^3/day$이며, 이중에서 차수벽 구간을 통과하여 유입되는 지하수량은 약 44.08~45.31 $m^3/day$로서 방안별로 유사한 것으로 나타났다. 따라서, 본 연구지역에서는 방안별 차수 효과보다는 시공성, 환경파괴의 최소성 등을 고려하여 최적의 차수벽 설치 방안을 제안하였다.

• 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.

• 한국통신학회논문지
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• 제22권1호
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• pp.89-95
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• 1997

X-cut y-propagation $LiNbO_{3}$ 광변조기를 해석하고, 광대역 변조특성을 얻기 위한 설계조건을 구한다. 먼저, 구성된 전극에 대하여 최대 변조효율을 얻기 위한 광도파로의 최적위치를 찾고, 다양한 설계조건에 따른 구동전압, 특성 임피던스, M/W 변조파 유효굴절율을 계산하였으며, 이와 같은 수치적 해석을 위해 유한요소법(FEM: Finite Element Method)을 사용하였다. 그리고 사용된 설계 틀의 유용성을 확인하기 위하여 Becker의 결과와 비교평가 하였다. 본 논문에서는 ridge형 도파로구조의 x-cut $LiNbO_{3}$ 광변조기에 대한 다양한 계산을 통하여, 결과적으로 $1.3{\mu}{\textrm{m}}$의 광신호에 대하여 1.8 V.cm의 구동전압과 특성임피던스 $48.13{\Omega}$ M/W(microwave) 변조파 유효굴절율 2.168을 가치는 x-cut $LiNbO_{3}$ 광변조기를 설계하였다.