• Title/Summary/Keyword: Omega-3

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Effect of Post-Annealing and ZTO Thickness of ZTO/GZO Thin Film for Dye-Sensitized Solar Cell

  • Song, Sang-U;Lee, Gyeong-Ju;No, Ji-Hyeong;Park, On-Jeon;Kim, Hwan-Seon;Ji, Min-U;Mun, Byeong-Mu
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.02a
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    • pp.405-406
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    • 2013
  • Ga-doped ZnO (GZO)는 $300^{\circ}C$ 이상의 온도에서는 전기적으로 불안정하기 때문에 CIGS, CdTe, DSC와 같은 태양전지의 높은 공정온도 때문에 사용이 제한적이다. ZTO thin film은 Al2O3, SiO2, TiO2, ZnO tihin film과 비교하여 산소 및 수분에 대하여 투과성이 상대적으로 낮은 것으로 알려져 있다. 따라서 GZO single layer에 비하여 ZTO-GZO multi-layer를 구성하여 TCO를 제작하면, 높은 공정온도에서도 사용 가능하다. 실제 제작된 GZO single layer (300 nm)에서 비저항이 $7.69{\times}10^{-4}{\Omega}{\cdot}cm$에서 $500^{\circ}C$에서 열처리 후 $7.76{\times}10^{-2}{\Omega}{\cdot}cm$으로 급격하게 상승한다. ZTO single layer (420 nm)는 as-grown에서는 측정 불가했지만, $400^{\circ}C$에서 열처리 후 $3.52{\times}10^{-1}{\Omega}{\cdot}cm$ $500^{\circ}C$에서 열처리 후 $4.10{\times}10^{-1}{\Omega}{\cdot}cm$으로 열처리에 따른 큰 변화가 없다. 또한 ZTO-GZO multi-layer (720 nm)의 경우 비저항이 $2.11{\times}10^{-3}{\Omega}{\cdot}cm$에서 $500^{\circ}C$에서 열처리 후 $3.67{\times}10^{-3}{\Omega}{\cdot}cm$으로 GZO에 비하여 상대적으로 변화폭이 작다. 또한 ZTO의 두께에 따른 영향을 확인하기 위하여 ZTO를 2 scan, 4 scan, 6 scan 공정 진행 및 $500^{\circ}C$에서 열처리 후 ZTO, ZTO-GZO thin film의 비저항을 측정하였다. ZTO의 경우 $3.34{\times}10^{-1}{\Omega}{\cdot}cm$ (2 scan), $3.62{\times}10^{-1}{\Omega}{\cdot}cm$ (4 scan), $4.1{\times}10^{-1}{\Omega}{\cdot}cm$ (6 scan)으로 큰 차이가 없으며, ZTO-GZO에서도 $3.73{\times}10^{-3}{\Omega}{\cdot}cm$ (2 scan), $3.42{\times}10^{-3}{\Omega}{\cdot}cm$ (4 scan), $3.67{\times}10^{-3}{\Omega}{\cdot}cm$ (6 scan)으로 큰 차이가 없음을 확인하였다. 염료감응 태양전지에 적용하여 기존에 사용되는 FTO대신에 ZTO-GZO를 사용하며, 가격적 측면, 성능적 측면에서 개선 가능할 것으로 생각된다.

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Dietary Fatty Acid Intakes of Employees in Employee Feeding Operations (사업체 집단급식소 근로자의 지방산 섭취 조사 연구)

  • 정은정
    • Journal of Nutrition and Health
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    • v.29 no.1
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    • pp.9-21
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    • 1996
  • This study was carried out to evaluate the fatty acid intakes of employees in employee feeding operations in Seoul and to provide prudent dietary guidelines with special concern on dietary fat. Four establishments were selected in large scale group and other four were selected as small scale group according to feeding numbers and food cost. Food intake was measured by substracting the leftover from the averaged portion amount. The leftover was measured by the modified aggregate selection plate waste measurement technique. The results were as follows : Employees from the large scale institution consumed more energy, protein, carbohydrate and niacin compared to those from the small scale institution(p<0.05). The mean calorie compositions of carbohydrate, protein and fat of all subjects were 66.7, 16.4 and 16.9%. The mean fat intake was 12.1g/lunch. Linoleic acid(C18:2 $\omega$6, 3.67g) was the most abundant fatty acid contained in the diet, followed by oleic acid (C18:1 $\omega$9, 3.53g) and palmitic acid(C16:0, 1.83g). The subjects consumed 5.2g polyunsaturated fatty acids(PUFA), 4.6g monounsaturated fatty acid(MUFA), 3.2g saturated fatty acid(SFA) per lunch per person. The average ratios of P/M/S and $\omega$6/$\omega$3 fatty acids were 1.6/1.5/1.0 and 8.5/1/0., respectively. the dietary $\omega$3 fatty acid status can be improved, even though the ratios found belong to the desirable range, by including $\omega$3 fatty acid rich-foods such as bean products and seafoods more frequently in the diet. Caution is needed for higher unsaturated nature of $\omega$3 series fatty acids to be prevented from peroxidation.

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BLOCH-TYPE SPACE RELATED WITH NORMAL FUNCTION

  • Choi, Ki Seong
    • Journal of the Chungcheong Mathematical Society
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    • v.24 no.3
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    • pp.533-541
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    • 2011
  • Let ${\omega}$ be a normal function. In this paper, we will extend the concept of Bloch space to Bloch-type space related with normal function ${\omega}$. We will investigate the properties of Bloch-type space ${\mathcal{B}}_{\omega}$ and the little Bloch-type space ${\mathcal{B}}_{{\omega},0}$ with weight ${\omega}$.

Stability Analysis of Combination Resonance Responses of a Circular Plate with Internal Resonance (내부공진을 가진 원판의 조합공진응답의 안정성 해석)

  • 이원경;김철홍
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 1993.04a
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    • pp.23-29
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    • 1993
  • 내부공진 (.omega.$_{3}$ = .omega.$_{1}$ + 2.omega.$_{2}$)을 가진 원판 의 조합공진(.OMEGA. = 2.omega.$_{1}$ + .omega.$_{2}$)응답의 안정성 을 해석한 결과 다음과 같은 결론을 얻었다. 1) 모든 진폭이 0(.alpha.$_{1}$=.alpha.$_{2}$=.alpha.$_{3}$=0)인 공진응답 은 매개변수의 값에 관계없이 안정하다. 2) 모든 진폭이 0이 아닌 (.alpha.$_{1}$.neq.0, .alpha.$_{2}$.neq.0, .alpha.$_{3}$.neq.0) 공진응답은 쌍으로 존재하는데 진폭이 큰 응답(upper branch)은 안정하나 진폭이 작은 응답(lower branch)은 불안정하다. 3) 진폭이 0이 아닌 공진응답이 존재하지 않는 경우에는 선형계와 마찬가지 로 모든 진폭이 0이 공진응답(결과적으로 비공진 응답)이 계의 응답을 지배 하지만 모든 진폭이 0이 아닌 공진응답이 존재하는 경우에는 안정한 공진응 답이 2개이므로 초기조건이 실제의 응답을 결정하게 된다.

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Some Notes on the Fourier Series of an Almost Periodic Weakly Stationary Process

  • You, Hi-Se
    • Journal of the Korean Statistical Society
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    • v.3 no.1
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    • pp.13-16
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    • 1974
  • In my former paper [3] I defined an almost periodicity of weakly sationary random processes (a.p.w.s.p.) and presented some basic results of it. In this paper I shall present some notes on the Fourier series of an a.p.w.s.p., resulting from [3]. All the conditions at the introduction of [3] are assumed to hold without repreating them here. The essential facts are as follows : The weakly stationary process $X(t,\omega), t\in(-\infty,\infty), \omega\in\Omega$, defined on a probability space $(\Omega,a,P)$, has a spectral representation $$X(t,\omega)=\int_{-\infty}^{infty}{e^{it\lambda\xi}(d\lambda,\omega)},$$ where $\xi(\lambda)$ is a random measure. Then, the continuous covariance $\rho(\mu) = E(X(t+u) X(t))$ has the form $$\rho(u)=\int_{-\infty}^{infty}{e^{iu\lambda}F(d\lambda)},$$ $E$\mid$\xi(\lambda+0)-\xi(\lambda-0)$\mid$^2 = F(\lambda+0) - F(\lambda-0) \lambda\in(-\infty,\infty)$, assumimg that $\rho(u)$ is a uniformly almost periodic function.

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Compact, Wavelength-selectable, Energy-ratio Variable Nd:YAG Laser at Mid-ultraviolet for Chemical Warfare Agent Detection

  • Kim, Jae-Ihn;Cho, Ki Ho;Lee, Jae-Hwan;Ha, Yeon-Chul
    • Current Optics and Photonics
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    • v.3 no.3
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    • pp.243-247
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    • 2019
  • We have developed a compact, wavelength-selectable, Q-switched Nd:YAG laser at mid ultraviolet for chemical warfare agent detection. The fundamental wave at 1064 nm is delivered by a pulsed solid state laser incorporating with a square-type Nd:YAG rod in a resonator closed by two crossed Porro prisms for environmental reliability. The output energy at 213 nm ($5{\omega}$) and 266 nm ($4{\omega}$) by ${\chi}^{(2)}$ process in the sequentially disposed BBO crystals are measured to be 6.8 mJ and 15.1 mJ, respectively. The output wavelength is selected for $5{\omega}$ and $4{\omega}$ by a motorized wavelength switch. The energy ratio of the $5{\omega}$ to the $4{\omega}$ is varied from 0.05 to 0.85 by controlling the phase matching temperature of the nonlinear crystal for sum-frequency generation without change of the output pulse parameters.

STATISTICS OF GRAVITATIONAL LENSING BY A GALAXY IN CLUSTER OR IN FIELD

  • YOON SO-YOON;PARK MYEONG-GU
    • Journal of The Korean Astronomical Society
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    • v.29 no.2
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    • pp.119-136
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    • 1996
  • To examine the effect of neighboring galaxies on the gravitational lensing statistics, we performed numerical simulations of lensing by many galaxies. The models consist of a galaxy in the rich cluster like Coma, or a galaxy surrounded by field galaxies in $\Omega_0 = 1$ universe with $\Omega_{gal} = 0.1,\;\Omega_{gal} = 0.3\;or\;\Omega_{gal}=1.0\;,\;where\;\Omega_{gal}$ is the total mass in galaxies. Field galaxies either have the same mass or follow Schechter luminosity function and luminosity-velocity relation. Each lensing galaxy is assumed to be singular isothermal sphere (SIS) with finite cutoff radius. In most simulations, the lensing is mainly due to the single galaxy. But in $\Omega_{gal} = 3$ universe, one out of five simulations have 'collective lensing' event in which more than two galaxies collectively produce multiple images. These cases cannot be incorporated into the simple 'standard' lensing statistics calculations. In cases where 'collective lensing' does not occur, distribution of image separation changes from delta function to bimodal distribution due to shear induced by the surrounding galaxies. The amount of spread in the distribution is from a few $\%\;up\;to\;50\%$ of the mean image separation in case when the galaxy is in the Coma-like cluster or when the galaxy is in the field with $\Omega_{gal} = 0.1\;or\;\Omega_{gal}=0.3.$ The mean of the image separation changes less than $5\%$ compared with a single lens case. Cross section for multiple image lensing turns out to be relatively insensitive to the presence of the neighboring galaxies, changing less than $5\%$ for Coma-like cluster and $\Omega_{gal}=0.1,\;0.3$ universe cases. So we conclude that Coma-like cluster or field galaxies whose total mass density $\Omega_{gal}<0.3$ do not significantly affect the probability of multiple image lensing if we exclude the 'collective lensing' cases. However, the distribution of the image separations can be significantly affected especially if the 'collective lensing' cases are included. Therefore, the effects of surrounding galaxies may not be negligible when statistics of lensing is used to deduce the cosmological informations.

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Experimental Investigation of R(ω), T(ω) and L(ω) for Multi-Layer SRRs and Wires Metamaterials

  • Luo, Hao;Wang, Xian;Liao, Zhangqi;Wang, Tao;Gong, Rongzhou
    • Journal of electromagnetic engineering and science
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    • v.10 no.3
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    • pp.186-189
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    • 2010
  • Reflection(R($\omega$)), transmission(T($\omega$)) and loss(L($\omega$)) characteristics of multi-layer metamaterials are investigated experimentally in free space with the incident EM waves perpendicular to the substrate plane. The sample is made of split-ring resonators(SRRs) and wires which are the typical model of metamaterials. The R($\omega$) and T($\omega$) of multi-layer metamaterials have been calculated from the measured S-parameters. In this paper, we got the impedance-matched result according to the curves of R($\omega$), meanwhile the T($\omega$) decreased with increasing number of layers. At last, we attained the result that the L($\omega$) gets to nearly 98% around 8 GHz, with R($\omega$)=T($\omega$)=0. The design presented in this paper achieves experimented loss near unity.

Omega-3 Polyunsaturated Fatty Acid for Cholestasis due to Bile Duct Paucity

  • Bae, Sun Hwan;Park, Hee Sun;Han, Hye Seung;Yun, Ik Jin
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.17 no.2
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    • pp.121-124
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    • 2014
  • Omega (${\omega}$)-3 polyunsaturated fatty acids appear to be effective in preventing and treating parenteral nutrition-associated liver disease, and several mechanisms were proposed for this observation. An 8-week-old male infant with cholestasis and acholic stool was diagnosed non-syndromic intrahepatic interlobular bile duct paucity by open-wedge liver biopsy. Initially he was treated with usual supportive medical therapy, including ursodeoxycholic acid. However, the clinical status and laboratory tests did not improve. Omega (${\omega}$)-3 polyunsaturated fatty acids (initially intravenous administration and oral administration later), were started and his liver function, including aminotransferase level and bilirubin levels normalized, and the ivory stool color turned green. We report the possible effectiveness of ${\omega}$-3 polyunsaturated fatty acids as a potent choleretic agent for non-syndromic intrahepatic interlobular bile duct paucity, a very rare structural pediatric hepatic disease.

Review on the Efficacy of Omega-3 in the Treatment of Attention-Deficit Hyperactivity Disorder (주의력결핍 과잉행동장애에서 오메가-3의 효과에 대한 고찰)

  • Park, So-Young;Lee, Soyoung Irene;Lee, Moon-Soo
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.27 no.1
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    • pp.31-38
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    • 2016
  • Pharmacotherapy is considered the first line therapy in attention-deficit hyperactivity disorder (ADHD). Many patients also choose complementary medicine such as dietary supplements. Omega-3 has shown some efficacy for improving ADHD symptoms in several studies. The goal of this review is to integrate the previous research findings on omega-3 and understand the issues worth considering in the treatment of ADHD. The terms "attention deficit disorder with hyperactivity", "omega-3", and "dietary supplements" were searched on PubMed, Cochrane, and Google scholar. The search was further limited to clinical trials, reviews, and meta-analyses. Trials that examined treatments for ADHD, used randomized design, and placebo-controlled trials were included. Eighteen clinical trials with a total of 1,141 participants were included in this review. Fifteen trials had parallel designs, comparing an omega-3/6 polyunsaturated fatty acid (PUFAs) or a combination of both to a placebo and three compared omega-3/6 PUFAs to a placebo and psycho-stimulants. Seven of the included trials showed significant improvements in groups receiving omega-3/6 PUFAs compared to placebo groups, however, 11 trials showed no significant differences. Evidence that PUFAs supplementation provides benefits for ADHD was yet limited. Mixed results were due to selection variability criteria, variability of supplementation, and short follow-up intervals.