• East Asian mathematical journal
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• 제19권1호
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• pp.151-164
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• 2003

Throughout this paper, we will consider that R is a near-ring and G is an R-group. We initiate the study of monogenic and strongly monogenic R-groups and their basic properties. Also, we investigate some properties of D.G. R-groups, faithful R-groups and monogenic R-groups and we determine that when near-rings are rings.

• 한국수학교육학회지시리즈B:순수및응용수학
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• 제18권4호
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• pp.305-312
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• 2011

In this paper, we denote that R is a near-ring and G an R-group. We initiate the study of the substructures of R and G. Next, we investigate some properties of R-groups, d.g. near-rings and monogenic (R, S)-groups.

• Carbon letters
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• 제12권2호
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• pp.70-80
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• 2011

Two pitches with different average molecular structures were electrospun and compared in terms of the properties of their fibers after oxidative stabilization, carbonization, and activation. The precursor with a higher molecular weight and greater content of aliphatic groups (Pitch A) resulted in better solubility and spinnability compared to that with a lower molecular weight and lower aliphatic group content (Pitch B). The electrical conductivity of the carbon fiber web from Pitch A of 67 S/cm was higher than that from Pitch B of 52 S/cm. The carbon fiber web based on Pitch A was activated more readily with lower activation energy, resulting in a higher specific surface area compared to the carbon fiber based on Pitch B (Pitch A, 2053 $m^2/g$; Pitch B, 1374 $m^2/g$).

• 대한수학회지
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• 제51권4호
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• pp.655-663
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• 2014

Let R be a ring with identity, X(R) the set of all nonzero, non-units of R and G(R) the group of all units of R. We show that for a matrix ring $M_n(D)$, $n{\geq}2$, if a, b are singular matrices of the same rank, then ${\mid}o_{\ell}(a){\mid}={\mid}o_{\ell}(b){\mid}$, where $o_{\ell}(a)$ and $o_{\ell}(b)$ are the orbits of a and b, respectively, under the left regular action. We also show that for a semisimple Artinian ring R such that $X(R){\neq}{\emptyset}$, $$R{{\sim_=}}{\oplus}^m_{i=1}M_n_i(D_i)$$, with $D_i$ infinite division rings of the same cardinalities or R is isomorphic to the ring of $2{\times}2$ matrices over a finite field if and only if ${\mid}o_{\ell}(x){\mid}={\mid}o_{\ell}(y){\mid}$ for all $x,y{\in}X(R)$.

• 한국작물학회지
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• 제51권4호
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• pp.340-347
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• 2006

Soyasaponins $A_1$, DDMP-conjugated group B soyasaponins ${\alpha}g\;and\;{\beta}g$, non-DDMP counterpart soyasaponin I, II+III, and DDMP moiety were quantified in the large-, midium-, and small-seed soybean varieties. Protein contents were ranged from 38.1% to 41.8%, and oil contents were ranged from 15.5% to 18.9%, respectively. Oil contents in the large-seed varieties were significantly higher than those of medium- and small-seed varieties. Among detected soyasaponin peaks, ${\beta}g$ was a major soyasaponin in DDMP-conjugated group B soyasaponins followed by soyasaponin I, DDMP moiety and $A_1$. Soyasaponin concentration among different seed size soybean varieties. The soyasaponin concentration of mediumseed ($4014.5{\mu}g/g$) was slightly higher than those of largeseed ($3755.0{\mu}g/g$) and small-seed varieties ($3620.3{\mu}g/g$), however, the differences was statistically not significant. The composition rates of soyasaponins in the large-size seeds were 9.4% of soyasaponin $A_1$, 26.5% of DDMP-conjugated soyasaponins, 49.9% of non-DDMP counterpart soyasaponins, and 14.2% of DDMP moiety, respectively. Similar results were observed in the composition ratios of middle- and small-size seeds. Oil content and C:N ratio showed the significant positive correlations with total soyasaponin concentration, while the 100-seed weight, fiber, and ash contents showed the negative correlations with total soyasaponin but statistically not significant. It was noted that protein contents didn't have any relationship with group A, group B, DDMP moiety, and total soyasaponin. This fact suggested that protein contents are not affects the variation of soyasaponin concentration.

• 소성∙가공
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• 제22권4호
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• pp.183-188
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• 2013

Scroll compressors are widely used in air conditioning systems and in automobiles due to their low pressure loss, minimal vibrations, and light-weight. Open-die forging with back pressure is used to forge the rotating scroll, and it requires special care since the forging die can be severely damaged at the fixed end of the spiral cavity similar to a fracture of a cantilever beam. To overcome the inevitable weakness of the forging die due to such damage, an innovative design is necessary. In this study, structural analysis using the finite element method was conducted to determine the reason for the fracture of the forging die. A novel design to avoid stress concentrations and vertical deflection, causing serious damage to the die, is suggested.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.63-66
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• 2001

원자력발전소는 지진과 같은 자연재해나 극한 운전조건에서 방사능물질이 외부로 누출되는 것을 방지하도록 설계 되어야한다. 따라서 이와 관련된 안전등급기기는 원전설비의 정상운전조건뿐 아니라 원전설계기준 사고조건(DBE, Design Basis Events)에서도 그 안전성 관련 기능이 검증되어야 한다. 본 연구에서는 국내 원자력 발전소의 다양한 환경조건을 만족하며 엄격한 기기검증요건에 따라 당사가 수행한 안전등급(Class 1E) 저압 유도전동기의 개발사례를 중심으로 방사능노출시험, 가속열노화해석 및 시험, 내진해석 및 시험으로 구성되는 기기검증의 절차와 방법을 제시하였다.

• Journal of Animal Science and Technology
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• 제47권5호
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• pp.899-904
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• 2005

본 연구는 강제낙각이 사슴뿔의 성장에 미치는 영향을 구명하기 위하여 꽃사슴 18두를 공시하여 뿔이 낙각 되기 40여일 전 강제 낙각을 실시하여 녹용생산량, 녹용길이 및 낙각시기에 미치는 영향을 조사하였으며 그 결과를 요약하면 다음과 같다. 1)뿔의 성장개시는 1차 년도에서 양쪽 절단구가 대조구에 비해 15일 정도 늦었으며, 다음 해 낙각시기는 절단구가 대조구보다 11-14일 빨랐다(P<0.05). 2)녹용 생산량은 1차년도에서 대조구, 한쪽 절단구 및 양쪽 절단구가 각각 775, 835 및 757g 이었고, 2차년도에서는 각각 1,004, 1,194 및 998g으로 한쪽 절단구의 녹용 생산량이 가장 많았으나 처리간에 유의성은 없었다. 3)녹용의 길이는 대조구, 한쪽 절단구 및 양쪽 절단구가 각각 25.8, 27.4 및 31.5 cm로 대조구에 비하여 한쪽 절단구 및 양쪽 절단구가 1년차에는 각각 1.6, 5.7cm 더 길었으며(P<0.05), 2년차에서도 각각 대조구보다 2.7, 2.4cm 더 길었다(P<0.05). 이러한 결과는 녹용의 생산시기 조절을 위하여 강제낙각을 응용한다면 녹용의 생산시기를 늦추거나 앞당기는데 충분히 활용할 수 있을 것으로 생각된다.

• Asian-Australasian Journal of Animal Sciences
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• 제18권3호
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• pp.375-383
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• 2005

An experiment was conducted to study the protective role of polyherbal feed supplement (Growell) during induced mycotoxicosis in broilers. A total of 240 Vencobb broilers were divided at day old stage into eight equal groups. Group A served as control and was given plain feed, group B, D, F and H were given Growell at 0.35 g/kg of feed. Group C, D, G and H were given dietary aflatoxin $B_1$ at 0.2 ppm and groups E, F, G and H were given ochratoxin A at 0.2 ppm in feed to study effect of Growell on individual aflatoxicosis, ochratoxicosis and combined mycotoxicosis of broilers. The chicks were given their respective feeds from 1st day to 6th week of age and were vaccinated at 7th and 28th day of age with Lasota strain of Newcastle disease virus. There was no statistically significant effect of mycotoxins individually or in combination on body weight of broilers. However, body weights were highest in group B and lowest in co-mycotoxicated group G. Feed conversion ratio was best in group B followed by A, D, F, E, H and G. Significant improvement in haemoglobin values was observed in broilers due to feeding of Growell in ochratoxin and co-mycotoxicated groups. There was no significant effect of mycotoxin treatment on PCV, TEC and TLC of broilers. Due to single and combined mycotoxicosis, there was reduction in serum total protein, albumin, cholesterol and triglyceride and rise in alkaline phosphatase, creatinine and uric acid levels. Supplementation of diets with Growell reduced the alterations induced due to mycotoxins. There was a significant rise in per cent organ weight of liver and reduction of that of spleen, bursa of Fabricius and thymus of broilers fed mycotoxins. Protection from alteration in per cent organ weight of these organ by supplementation of Growell was recorded. The observed impaired immune response and histopathological changes in liver, kidney, spleen, bursa of Fabricius and thymus of broilers given mycotoxins were protected by supplementation of Growell.

• 한국가금학회지
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• 제33권2호
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• pp.159-164
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• 2006

본 연구는 사료와 음수에 함유된 염분 수준이 육계 초기 병아리에 미치는 영향을 조사하기 위하여 실시하였다. 1일령 초생추(Hubbard)를 공시하여 14일 동안 시험을 수행하였다. 시험 1에서, 사료내 염분 함량은 0, 0.25, 0.5, 0.75, 1.0, 2.0, 3.0, 4.0%로 조절하여 8처리구 처리구당 3반복, 반복당 12수씩 총 288수에 급여하였고, 시험 2에서, 음수내 염분 함 량은 0, 0.1, 0.2, 0.5, 1.0%로 조절하여 5처리구 처리구당 3반복, 반복당 12수씩 총 180수에 공급하였다. 시험 1의 경우에, 사료 섭취량과 증체량은 사료내 염분 함량이 증가할수록 감소하는 경향이었다. 특히 4% 처리구에서 각각 481 g과 168 g으로 가장 낮았으며, 폐사율은 75%로 가장 높았다. 시험 2의 경우에는, 음수 1% 처리구에서 사료 섭취량과 증체량은 각각 427 g과 162 g이었고, 폐사율은 77.8%로 가장 높았다. 염 중독 증상을 나타낸 닭들은 갈증, 식욕부진, 기립불능, 졸림, 경련 등을 나타내었고, 부검 소견에서는 복수증, 심낭수종, 심비대, 각종 장기의 출혈 등이 나타났다. 이상의 결과로 육계 초기에서 사료내 염분 함량이 3%, 음수내 염분 함량은 1% 이상에서 뚜렷한 생산성의 저하는 물론 생리 해부학적인 염분중독 증상이 나타남을 알 수 있다.