• Title/Summary/Keyword: dB difference

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Effect of Zirconium Dioxide in BaO-ZnO-B2O3-SiO2 system on Optical Properties of Color Conversion Glasses

  • Jeong, HyeonJin;Jeon, Dae-Woo;Kim, Jin-Ho;Lee, Young Jin;Lee, MiJai;Hwang, Jonghee;Lee, Jungsoo;Yang, Yunsung;Youk, Sookyung;Park, Tae-Ho;Shin, Dongwook
    • Journal of the Korean Ceramic Society
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    • v.53 no.2
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    • pp.258-262
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    • 2016
  • The effect of zirconium dioxide ($ZrO_2$) on the properties of color conversion glasses was examined in the $BaO-ZnO-B_2O_3-SiO_2$ system. The difference in refractive index between glass and phosphor affect the optical properties of the color conversion glass because of light scattering. Reducing the difference in refractive index is a method to improve the luminous efficacy of color conversion glasses. As a reference, a type of glass that contains 25 mol% of each component was used. To increase the refractive index of the glass samples, the BaO content was increased from 25 to 40 mol%, and $ZrO_2$ was added at levels of 1, 3, and 5 mol%. Color conversion glasses were prepared by sintering a mixture of glass and 5 wt% $YAG:Ce^{3+}$ phosphor. As a result, the refractive index of the glass was found to be dependent on the BaO and $ZrO_2$ contents in the BaO-ZnO-$B_2O_3-SiO_2$ system. As the BaO and $ZrO_2$ contents were increased, the luminous efficacy of the color conversion glass was improved because the refractive index difference between the glass and the $YAG:Ce^{3+}$ phosphor decreased.

Bit-Rate Control Using Histogram Based Rate-Distortion Characteristics (히스토그램 기반의 비트율-왜곡 특성을 이용한 비트율 제어)

  • 홍성훈;유상조;박수열;김성대
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.24 no.9B
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    • pp.1742-1754
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    • 1999
  • In this paper, we propose a rate control scheme, using histogram based rate-distortion (R-D) estimation, which produces a consistent picture quality between consecutive frames. The histogram based R-D estimation used in our rate control scheme offers a closed-form mathematical model that enable us to predict the bits and the distortion generated from an encoded frame at a given quantization parameter (QP) and vice versa. The most attractive feature of the R-D estimation is low complexity of computing the R-D data because its major operation is just to obtain a histogram or weighted histogram of DCT coefficients from an input picture. Furthermore, it is accurate enough to be applied to the practical video coding. Therefore, the proposed rate control scheme using this R-D estimation model is appropriate for the applications requiring low delay and low complexity, and controls the output bit-rate ad quality accurately. Our rate control scheme ensures that the video buffer do not underflow and overflow by satisfying the buffer constraint and, additionally, prevents quality difference between consecutive frames from exceeding certain level by adopting the distortion constraint. In addition, a consistent considering the maximum tolerance BER of the voice service. Also in Rician fading channel of K=6 and K=10, considering CLP=$10^{-3}$ as a criterion, it is observed that the performance improment of about 3.5 dB and 1.5 dB is obtained, respectively, in terms of $E_b$/$N_o$ by employing the concatenated FEC code with pilot symbols.

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Assessment of vitamin $B_6$ status in Korean patients with newly diagnosed type 2 diabetes

  • Ahn, Hee-Jung;Min, Kyung-Wan;Cho, Youn-Ok
    • Nutrition Research and Practice
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    • v.5 no.1
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    • pp.34-39
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    • 2011
  • The purpose of this study was to assess vitamin $B_6$ intake and status in Korean patients with newly diagnosed type 2 diabetes. Sixty-four patients with newly diagnosed type 2 diabetes and 8-11% glycated hemoglobin (A1C), along with 28 age-matched non-diabetic subjects, participated. Dietary vitamin $B_6$ intake was estimated by the 24 hour recall method and plasma pyridoxal 5'-phosphate (PLP) was measured. There was a significant difference in daily total calorie intake between the diabetic and non-diabetic groups ($1,917{\pm}376$ vs $2,093{\pm}311\;kcal$). There were no differences in intake of total vitamin $B_6$ ($2.51{\pm}0.91$ vs $2.53{\pm}0.81\;mg/d$) or vitamin $B_6$/1,000 kcal ($1.31{\pm}0.42$ vs $1.20{\pm}0.32\;mg$) between the diabetic and non-diabetic groups, and I intakes of total vitamin $B_6$ were above the Korean RDA in both groups ($180.0{\pm}57.9$ vs $179.0{\pm}65.4$). There was a higher percentage of diabetic subjects whose plasma PLP concentration was < 30 nmol/L compared to non-diabetic group. Plasma PLP levels tended to be lower in the diabetic subjects than in the non-diabetic subjects, although the difference was not statistically significant due to a large standard deviation ($80.0{\pm}61.2\;nmol/L$ vs $68.2{\pm}38.5\;nmol/L$). Nevertheless, plasma PLP levels should be monitored in pre-diabetic patients with diabetic risk factors as well as in newly diagnosed diabetic patients for long-term management of diabetes, even though this factor is not a major risk factor that contributes to the development of degenerative complications in certain patients.

Design of Millimeterwave Branch-Line Coupler Using Flip-Chip Technology (플립 칩 기술을 이용한 밀리미터파 대역 브랜치라인 커플러의 설계)

  • Yoon, Ho-Sung;Lee, Hai-Young
    • Journal of the Korean Institute of Telematics and Electronics D
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    • v.36D no.9
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    • pp.1-5
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    • 1999
  • In this paper, we proposed a novel branch-line coupler using filp-chip technology. The proposed coupler consists of CPW and inverted microstrip. The CPW is on the GaAs flip-chip substrate, and the inverted microstrip is on the alumina main substrate. The ground plane of the CPW is used as a ground plane of the inverted microstrip. And both the transmission lines are connected by solder bump with each other. The characteristics of thisstructure was calculated by FDTD method. The S21, S31 are -3dB and the phase difference is $90^{\circ}$. The calculated characteristics are the same as those of the regular branch-line coupler. This structure can be applied for various kinds of devices using flipchip technology.

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Study on Electrical Environmental Obstacle Using a 765kV Double Circuit Test Line (765kV 시험선로를 이용한 전기환경장해 특성연구)

  • Kim, Jeong-Boo;Jo, Seong-Sae;Shin, Goo-Yong;Lee, Dong-Il;Yang, Kwang-Ho;Ahn, Hee-Sung;Bae, Jeong-Hyo;Koo, Ja-Yoon;Min, Seok-Weon
    • Proceedings of the KIEE Conference
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    • 1994.07b
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    • pp.1517-1519
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    • 1994
  • This paper describes electrical environmental study of a 765kV double circuit test line. Corona performance on several candidate conductor bundles has been investigated in the corona cage (single phase simulation facility) since 1984. We have known that six RAIL conductor bundle is the most suitable for the 765kV transmission Line, [3] To investigate electrical environmental impact of the future commerciale line, we build a full sacle 765kV test line in 1993. The test results of Audible Noise, Radio Interference, TV Interference from August, 1993 to Jan. 1994 were measured as $48.7[dBA](L_{50})$. $57.4[dB{\mu}V/m]$(Fair weather, $L_{50})$. $14.5[dB${\mu}$V/m]$(Fair weather, $L_{50}$). We have found that the Audible Noise data were very close to the predicted(48.5 [dBA]) by BPA Corona and Field Effects Computer program, however, the RI and TVI data were much higher than predicted(42 [dBmV/m], $7.9[dB{\mu}V/m)$ by the BPA program. We have investigating the reason of the difference. In the constructing of full scale test line, we developed the tubular tower, 765kV test transformer and hardwares of 765kV transmission line insulator strings. Also we will investigate the effects of plants under the 765kV test Line.

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Comparison of old-old aged women's bodice pattern using 3D anthropometric data

  • Cha, Su-Joung
    • Journal of the Korea Society of Computer and Information
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    • v.23 no.11
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    • pp.111-122
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    • 2018
  • The purpose of this study was to investigate the bodice prototype method suitable for the upper body shape of old-old aged women using the 3D anthropometric data. And it was to provide the basic data for the upper body garments of old-old aged women. In the overall appearance evaluation, the B pattern was rated as 4.00, and it was evaluated as the most suitable for the bodice prototype of the old-old aged woman. The E pattern was rated lower than normal, and the L pattern and the S pattern were found to be inadequate for older female bodice prototypes. As a result of the measurement of the waist and bust air gap of bodice prototype, the air gap of the bust was not significantly different between the patterns. But the waist air gap showed the largest difference between the L pattern and the S pattern. As a result of evaluating the appearance, the amount of space in the state of 3D simulation, and the air gap, the pattern B appeared to be the most appropriate prototype for the old-old aged women's body shape. However, there is a tendency that the shoulder end point is biased toward the back, so it is necessary to set the inclination of the back shoulder line to be more gentle. Conversely, the front shoulder should be more inclined. In the case of the 3D simulation, the B pattern showed that the other parts generally fit well. In the case of the 3D simulation program used in this study, it was evaluated that it is suitable only for the normal body shape because it is impossible to set the isometric angle which is one of the characteristics of the older female body shape. A study on the bodice prototype suitable for the bent body shape should be carried out through experiments on the actual body shape of various elderly women. In order to cope with the increase of elderly people who are familiar with digital, I think it is necessary to develop an avatar that reflects the old female body shape.

Differences in serum ferritin and vitamin D levels of Korean women with obesity and severe obesity (비만과 고도비만 한국 여성의 혈청 페리틴과 비타민 D 수준의 비교)

  • Kang, Nan Hui;Park, Ji Sook;Lee, Hongchan;Yim, Jung-Eun
    • Journal of Nutrition and Health
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    • v.53 no.4
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    • pp.381-389
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    • 2020
  • Purpose: This study examined the relationships among serum ferritin, vitamin D, folate, iron, and vitamin B12 as indicators of obesity. The results provide the basic data for the prevention and treatment of obese and severely obese people. Methods: This study selected 44 people from 18 years of age or older to 59 years. This study used the indicators of the body mass index (BMI) to analyze obesity as the obesity group (BMI of 25.0-29.9 kg/㎡) and as the severe obesity group (BMI ≥ 30.0 kg/㎡). Of the 44 subjects, 23 and 21 subjects were in the obesity and severe obesity groups, respectively. Their height, weight, body fat, skeletal muscle mass measured using bioimpedance analysis, and measured serum nutrients and biochemical parameters. Results: The obesity group showed a significantly lower age, body weight, BMI and body composition, body fat mass, and body fat percentage, and the height was significantly lower in the severe obesity group. The results of the biochemical parameters of the subjects showed that the levels of aspartate transaminase, alanine transaminase, hemoglobin A1c, total cholesterol, and triglyceride were within the normal range, and there was no significant difference between the 2 groups. The levels of folate, vitamin B12, 25-hydroxyvitamin D3, iron, and ferritin were almost normal, and there was no significant difference between the 2 groups. Conclusion: This study revealed an association with the serum nutrients and obesity, but there was no difference between the obesity group and severe obesity group. Observations of the nutrient levels in not only the blood in obesity and severe obesity but also in red blood cells and tissues will be necessary.

Effect of Feeding Induced Molting on the Visceral Organs and Blood Component Profile in Laying Hens (비절식 강제 환우 방법이 산란계의 장기 비율과 혈액 성상에 미치는 영향)

  • Na, J.C.;Park, S.B.;Yu, D.J.;Bang, H.T.;Kim, S.H.;Kang, G.H.;Kim, H.K.;Choi, H.C.;HwangBo, J.;Kang, B.S.;Suh, O.S.;Jang, B.G.;Choi, J.T.
    • Korean Journal of Poultry Science
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    • v.35 no.4
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    • pp.375-380
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    • 2009
  • This study was conducted to investigate the effect of feeding induced molting on the visceral organs and blood component profile in laying hens and designed to test 400 flocks of 60 week old Leghorn laying hens for 34 weeks. A total of four molting treatment methods by including the molted with customary molting by fasting method (c), feeding single diet of corn (T1), feeding single diet of wheat bran (T2) and feeding single diet of alfalfa meal (T3) were tested, and each treatment was repeated for 5 times, and 20 laying hens were randomly assigned in an cage for each repeat. As the result of the experiment, ovary was $2.03{\sim}6%$ and oviduct was $2.51{\sim}3.47%$ in visceral organs for body weight at pre-molting term, but there was no significant difference. At post-molting, no significant difference was found, ovary was $0.25{\sim}0.41%$, uterus of control, T1, T2 and T3 was 1.12%, 0.82%, 0.48% and 0.90%, respectively. T2 was significantly lower than control, T3 (p<0.05) at the 50% of egg production. Ovary was $2.20{\sim}2.60%$ and oviduct was $2.98{\sim}3.45%$. In addition, ovary was $2.65{\sim}3.01%$, oviduct was $3.23{\sim}3.64%$ at the peak egg production, but there was no significant difference by non-feeding and feeding molting treatments. In blood component profile, cholesterol was $179.8{\sim}245.7\;mg/dL$ at pre-molting, but there was no significant difference and at post-molting, concentration of cholestrol in control, T1, T2 and T3 was 353.6, 229.1, 261.8 and 300.6 mg/dL, respectively. T1 was significantly lower than control and T3 (p<0.05). In addition, first laying day was $228.1{\sim}271.8\;mg/dL$, 50% of egg production was $236.5{\sim}284.8\;mg/dL$, there was no significant difference. Concentration of cholestrol in control, T1, T2 and T3 was 324.1, 591.6, 363.0 and 315.6 mg/dL, respectively, at the peak egg production period. T1 was significantly higher than other treatment (p<0.05).

Characteristic Analysis of a Magnet for Magnetically Levitated Vehicle using FLUX3D (FLUX3D를 이용한 자기부상용 전자석의 특성 해석)

  • Lee, Jae-Kun;Shin, Pan-Seok
    • Proceedings of the KIEE Conference
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    • 1996.07a
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    • pp.127-129
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    • 1996
  • A 3-dimensional analysis is desired for a magnet of magnetically levitated vehicle because the geometrical shape of the magnet is complicated and nonsymmetric. A FEM package of FLUX3D is used to analyze the characteristic of the magnet. Various quantities could be observed like levitation force, flux density distribution along the air gap, edge and fringing effect, leakage flux pattern, etc. The simulation results from FLUX3D are compared with those of 2-D analysis and test results. There are a little difference between results due to the boundary conditions and magnetized B-H curve of the core.

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Parametric studies on convection during the physical vapor transport of mercurous chloride ($Hg_2Cl_2$)

  • Kim, Geug-Tae;Lee, Kyong-Hwan
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.14 no.6
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    • pp.281-289
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    • 2004
  • The temperature hump is found to be most efficient in suppressing parasitic nucleation. With the temperature humps, there are found to be observed in undersaturations along the transport path for convective-diffusive processes ranging from $D_{AB}$ = 0.0584 $\textrm{cm}^2$/s to 0.584 $\textrm{cm}^2$/s, axial positions from 0 to 7.5 cm. With decreasing Ar = 5 to 3.5, the temperature difference is increased because of the imposed nonlinear temperature profile but the rate is decreased. For 2 $\leq$ Ar $\leq$ 3.5, the rate is increased with the aspect ratio as well as the temperature difference. Such an occurrence of a critical aspect ratio is likely to be due to the effect of sidewall and much small temperature difference. The rate is decreased exponentially with the aspect ratio for 2 $\leq$ Ar $\leq$ 10. Also, the rate is exponentially decreased with partial pressure of component B, P for 1 $\leq$ P $\leq$ 100 Torr.$ B/ $\leq$ 100 Torr.