• 마이크로전자및패키징학회지
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• 제18권4호
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• pp.33-38
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• 2011

p형 $(Bi_{0.2}Sb_{0.8})_2Te_3$ 분말을 기계적 합금화 공정으로 제조하여 가압소결 후 가압소결온도에 따른 열전특성을 분석하였다. 가압소결온도를 $350^{\circ}C$에서 $550^{\circ}C$로 증가시킴에 따라 상온에서 측정한 Seebeck 계수가 237 ${\mu}V/K$에서 210 ${\mu}V/K$로 감소하고 전기비저항이 2.25 $m{\Omega}-cm$에서 1.34 $m{\Omega}-cm$로 감소하였으며, power factor가 $25.0{\times}10^{-4}W/m-K^2$에서 $32.9{\times}10^{-4}W/m-K^2$로 증가하였다. $350{\sim}550^{\circ}C$의 온도범위에서 가압소결한 시편들 중에서, $500^{\circ}C$에서 가압소결한 $(Bi_{0.2}Sb_{0.8})_2Te_3$ 가압소결체가 상온에서 1.09 및 $75^{\circ}C$에서 1.2의 가장 높은 무차원 성능지수를 나타내었다.

• Journal of Nutrition and Health
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• 제32권8호
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• pp.897-907
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• 1999

The purpose of this study was to investigate the pattern of individual fatty acid intake and to compare total serum lipid levels and total serum fatty acid composition of elementary school children in Seoul by fish and meat intakes. The subjects were divided into High-Fish / Low-Meat(HFLM, n=49) and Low-Fish/High-Meat(LFHM, n=47) group. The total energy from fat of HFLM and LFHM group was 22.0 and 30.0% respectively. The average intake of cholesterol was 237-287mg in HFLM group and 358-387mg in LFHM group. The average P/M/S ratio for all subjects was 1.1-1.4/1.1 - 1.2/1.0, which was very similar to desired ratio. The $\omega$6/$\omega$3 ratio of dietary fatty acids of HFLM and LFHM group were 8.0-10.9 and 18.9-29.3 respectively, which in case of LFHM group, was fat beyond the suggested range, 4/1 - 10.1. Serum lipid levels of all subjects fell within the normal range and there was no significant difference in serum lipid levels between HFLM and LFHM groups, except for HDL-cholesterol in upper grades(4th-6th grades). In lower grades(1st-3rd grades), serum PUFA composition of HFLM (40.8%) group was significantly higher than that of LFHM (38.3%) group (p<0.05) and SFA composition of HFLM(33.8%) was significantly lower than that of LFHM group, (p<0.001) between them. The $\omega$6/$\omega$3 ratio of serum fatty acid tended to be higher in LFHM than in HFLM group but there was no significant difference between two groups. This study suggests that the dietary fat pattern of growing children could affect the change in total serum fatty acid composition though it did not influence serum lipid levels significantly. Energy and EPA intakes were negatively correlated with HDL-cholesterol levels(p<0.05). Serum fatty acid compositions were more closely correlated with serum triglyceride(TG) levels than serum cholesterol levels. Especially, total SFA (p<0.001) and individual SFA, such as C14:0(p<0.001) and C16:0(p<0.001)compositions were positively correlated with serum TG levels, but stearic acid(p<0.01) was negatively correlated with it.

• 한국토양비료학회지
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• 제44권3호
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• pp.492-497
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• 2011

경남지역 과수원 토양 25개소를 대상으로 2010년에 미생물 군집을 분석하고 토성, 지형 및 작물별 주요 변동요인을 주성분 분석으로 해석하였다. 경남지역 과수원 토양 평균값은 총 FAME 함량이 $332nmol\;g^{-1}$이었으며 총 세균 함량은 $94nmol\;g^{-1}$, 그람음성 세균 함량은 $46nmol\;g^{-1}$, 그람양성 세균은 $42nmol\;g^{-1}$, 방선균 함량은 $4.8nmol\;g^{-1}$, 곰팡이 함량은 $54nmol\;g^{-1}$, 내생균근균 함량은 $9.1nmol\;g^{-1}$ 이었다. 미생물의 환경스트레스 지수인 토양 cy19:0과 18:$1{\omega}7c$ 비율은 사양토에서 0.36으로 양토 0.80 보다 유의적으로 낮아 (p<0.05) 토양 미생물의 스트레스가 적었다. 과수원 토양 평균 미생물은 총 세균이 28.1%, 곰팡이 15.9%, 그람음성 세균은 13.6%, 그람양성 세균은 12.5%, 내생균근균 2.8%, 방선균 1.4%의 비율을 나타냈다. 복숭아 재배지의 토양 그람음성 세균 군집은 15.2%로서 배 재배지 12.8%에 비해 유의적으로 높은 비율을 나타냈다 (p<0.05). 주성분 분석결과 지형, 토성, 작물별 유의적인 차이가 없었으며 토양 미생물 군집의 다양성을 관리하기 위해 지속적인 모니터링이 필요할 것으로 생각된다.

• 한국식품영양학회지
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• 제23권4호
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• pp.516-525
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• 2010

아마인의 유용성분에 대해서 알아보고 가열과정을 통한 성분변화 및 다른 종유작물과 유지의 물리화학적 성분과 비교, 평가하였다. 조지방은 37~43%, 탄수화물은 30~35%, 조단백질은 18~23%, 조회분은 3~4% 그리고 수분 함량은 0.2~6.8%의 함량을 나타내었다. 식이섬유 함량은 생아마인보다 가열 처리한 볶음 아마인에서 SDF의 함량이 증가한 것을 알 수 있었다. 하지만 상대적으로 IDF의 함량도 감소하기 때문에 TDF의 함량은 큰 차이를 보이지 않았다. 그리고 총 식이섬유 함량은 28~31%로 높은 함량을 보였다. 또한 아마인의 주요 유용성분을 살펴본 결과, 비타민은 ${\gamma}$-tocopherol(E), 아미노산은 agrginine, aspartic acid, glutamic acid가 높은 함량을 보였다. 이들은 생아마인보다 볶음 아마인에서 낮은 함량을 나타내었다. 아마인의 무기물 함량을 분석한 결과, 칼슘, 칼륨, 마그네슘, 인이 주요 구성성분이었다. 물리화학적인 특징으로 요오드가, 비누화가, 산가를 분석하였으며, 브라운 아마인유는 각각 204.1 g/100 g, 193.6 mg/g, 1.59 mg/g을 나타내었으며, 골드 아마인유는 각각 203.0 g/100 g, 189.9 mg/g, 2.35 mg/g으로 조사되었다. 아마인유의 지방산 함량에서는 전체적인 구성 비율을 볼 때 ${\alpha}$-linolenic acid(ALA, C18:3n-3)가 약 55.5~56.1% 로 가장 높은 함량을 차지하였다. 그리고 브라운보다는 골드 아마인유의 ${\alpha}$-linolenic acid의 함량이 약간 높았다. 높은 ${\alpha}$-linolenic acid 함량은 아마인유가 오메가-3 지방산이 강화된 식품 개발에 좋은 자원이 될 것으로 사료된다. 또한 다가 불포화지방산 함량이 약 71%로 함유되어 있으며, ${\alpha}$-linolenic acid 등 필수지방산의 함량이 높아 식품의 영양학적인 의의가 크며, 양질의 식용유로 사용 가능할 것이다.

• 상하수도학회지
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• 제25권4호
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• pp.591-596
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• 2011

Surface floating air cathode microbial fuel cell (MFC) having horizontal flow was developed for the application of MFC technology. RVC (Reticulated vitreous carbon) coated with anyline was used as anode electrode and carbon cloth coated with Pt (5.0 g Pt/$m^2$, GDE LT250EW, E-TEK) was used as cathode electrode. As results of continuous operation with changing the flow rate from 4.3 mL/min to 9.5 mL/min, maximum power density of 4.5 W/$m^3$ was acquired at 5.4 mL/min, which was at 0.35 m/hr of flow velocity under anode electrode. When the ratio of cathode surface area to anode surface area($A_c/A_a$) was changed to 1.0, 0.5, and 0.25, the maximum power density of 2.7 W/$m^3$ was shown at the ratio of 1.0. As the ratio decreased from 1.0 to 0.25, the power density also decreased, which is caused by increasing the internal resistance resulted from reducing the surface area to contact with oxygen. Actually, internal resistances of the ratio of 1.0, 0.5, and 0.25 were 63.75${\Omega}$, 142.18${\Omega}$, and 206.12${\Omega}$, respectively.

• Journal of Nutrition and Health
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• 제33권1호
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• pp.13-22
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• 2000

Effects of high fat diet and/or endurance exercise training on hepatic total and phospholipid(PL) fatty acid compositions were evaluated in rats fed one of the following diets for 31 days. control diet(CD, 5 wt% corn oil) or high fat diet(HFD, 35 wt% corn oil). Half of the rats in each group were exercise-trained regularly on a treadmill for 90 minutes/day during the entire feeding period. Total and PL fatty acid compositions of hepatic lipid extracts were determined by a gas-liquid chromatograph),. Endurance exercise training did not change the daily food intake, but significantly reduced body weight gain and feed efficiency ratio of rats, which were most prominent in animals fed HFD. Exercise training did not significantly change the percentages of ∑saturated fatty acids (SFA) and ∑polyunsaturated fatty acids(PUEA), but decreased the percentage of ∑monounsaturated fatty acids(MUFA) in hepatic total fatty acids, which might be associated with the decrease in (equation omitted) 9-desaturation index of hepatic total fatty acid metabolism. Exercise training significantly lowered the percentages of 16 : 0 and 22 : 5$\omega$3, and increased the percentages of 20 : 1 and 20 : 3$\omega$3 in both total and PL fatty acid compositions in rat liver. Both total fatty acid and PL fatty acid compositions of rat liver responded more sensitively to changes in dietary fat content than to endurance exercise training in this study. Feeding HFD, whoch contains high level of linoleic acid(LA, 18 : 2$\omega$6), significantly decreased the percentages of ∑SFA and $\Sigma$MUFA, and increased the percentages of ∑PUFA and ∑$\omega$6 fatty acids of hepatic total fatty acids. Hepatic total fatty acid composition was affected by dietary fat content and dietary fatty acid composition more sensitively than those found in hepatic PL fatty acid composition. HFD significantly decreased most of desaturation indices, while exercise training significantly decreased elongation index(20 : 5$\omega$3⇒22 : 5$\omega$3) of hepatic total and PL fatty acid metabolism in rats. (Korean J Nutrition 33(1) : 13-22, 2000)

• Transactions on Electrical and Electronic Materials
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• 제9권2호
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• pp.67-72
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• 2008

Al-doped p-type ZnO thin films were fabricated by RF magnetron sputtering on n-Si (100) and homo-buffer layers in pure oxygen ambient. ZnO ceramic mixed with 2 wt% $Al_2O_3$ was selected as a sputtering target. XRD spectra show that the Al-doped ZnO thin films have ZnO crystal structure. Hall Effect experiments with Van der Pauw configuration show that p-type carrier concentrations are arranged from $1.66{\times}10^{16}$ to $4.04{\times}10^{18}\;cm^{-2}$, mobilities from 0.194 to $198\;cm^2V{-1}s^{-1}$ and resistivities from 0.0963 to $18.4\;{\Omega}cm$. FESEM cross section images of different parts of a p-type ZnO:Al thin film annealed at $800^{\circ}C$ show a compact structure. Measurement for same sample shows that density is $5.40\;cm^{-3}$ which is smaller than theoretically calculated value of $5.67\;cm^{-3}$. Photoluminescence (PL) spectra at 10 K show a shoulder peak of p-type ZnO film at about 3.117 eV which is ascribed to electron transition from donor level to acceptor level (DAP).

• 한국초전도ㆍ저온공학회논문지
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• 제9권1호
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• pp.76-81
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• 2007

This paper deals with the characteristics of a small scale $high-T_c$ superconducting(HTSC) levitation system. The levitation tester. which models after electrodynamic suspension(EDS) maglev, consists of one HTSC magnet, a reaction plate, and force measuring components. Instead of moving magnet, AC current was applied to the fixed HTSC magnet. The magnet also has persistent current switch(PCS). The inductance of the magnet was 18.5 mH and total joint resistance of the magnet was $5.74{\times}10^{-7}\Omega$. AC current was applied into the HTSC magnet with various frequencies and the levitation force was calculated and measured. According to the increase of the vehicle speed, the levitation force was saturated.

• 대한수학회지
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• 제59권2호
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• pp.353-365
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• 2022

Let 𝓐 be the collection of analytic functions f defined in 𝔻 := {ξ ∈ ℂ : |ξ| < 1} such that f(0) = f'(0) - 1 = 0. Using the concept of subordination (≺), we define $$S^*_{\ell}\;:=\;\{f{\in}A:\;\frac{{\xi}f^{\prime}({\xi})}{f({\xi})}{\prec}{\Phi}_{\ell}(\xi)=1+{\sqrt{2}{\xi}}+{\frac{{\xi}^2}{2}},\;{\xi}{\in}{\mathbb{D}}\}$$, where the function 𝚽_ℓ(ξ) maps 𝔻 univalently onto the region Ω_ℓ bounded by the limacon curve (9u² + 9v² - 18u + 5)² - 16(9u² + 9v² - 6u + 1) = 0. For 0 < r < 1, let 𝔻_r := {ξ ∈ ℂ : |ξ| < r} and 𝒢 be some geometrically defined subfamily of 𝓐. In this paper, we find the largest number 𝜌 ∈ (0, 1) and some function f₀ ∈ 𝒢 such that for each f ∈ 𝒢 𝓛_f (𝔻_r) ⊂ Ω_ℓ for every 0 < r ≤ 𝜌, and $${\mathcal{L} _{f_0}}({\partial}{\mathbb{D}_{\rho})\;{\cap}\;{\partial}{\Omega}_{\ell}\;{\not=}\;{\emptyset}$$, where the function 𝓛_f : 𝔻 → ℂ is given by $${\mathcal{L}}_f({\xi})\;:=\;{\frac{{\xi}f^{\prime}(\xi)}{f(\xi)}},\;f{\in}{\mathcal{A}}$$. Moreover, certain graphical illustrations are provided in support of the results discussed in this paper.

• 한국축산식품학회지
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• 제34권5호
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• pp.622-629
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• 2014

The present study was conducted to compare the growth performance, carcass characteristics, and meat quality of the egg-type male growing chicken (EM), white-mini broiler (WB), and commercial broiler (Ross 308, CB). A total of 360 1-d-old chicks were reared together using a completely randomized design with 4 replicates for each group under the identical feeding and rearing conditions. The ADG and gain:feed were the highest in CB, intermediate in WB, and the lowest in EM (p<0.05), and the live and carcass weights of CB and EM were significantly higher than those of WB (p<0.05). The pH of breast meat from WB and CB was significantly higher (p<0.05) than that from EM with a similar body weight. The EM had the lowest moisture (p<0.05) and the highest protein content (p<0.05), whereas the fat and ash contents were not different among groups. The mystiric acid (C14:0), palmitoleic acid (C16:1 ${\omega}7$), and oleic acid (C18:1 ${\omega}9$) levels were significantly higher in breast meat from CB (p<0.05). The monounsaturated fatty acid (MUFA) content showed the highest (p<0.05) levels in CB. In contrast, the polyunsaturated fatty acid (PUFA) contents of breast meat, including linoleic acid (C18:2 ${\omega}6$) and arachidonic acid (C20:4 ${\omega}6$), were higher (p<0.05) in EM and WB than in CB. In conclusion, the EM and WB had less growth performances in comparison with CB, but they each had some unique features (taste, flavor, and physiological characteristics) when raised under the identical rearing and feeding conditions.