• Title/Summary/Keyword: D D C

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A Study of Selection of Existing A.C. Transmission Facilities for Use with D.C. (기존 교류선로의 직류변환 송전방식에 있어서 선정기법에 관한 연구)

  • Kim, D.J.;Moon, Y.H.;Lee, D.I.;Yoon, J.Y.;Yang, K.H.
    • Proceedings of the KIEE Conference
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    • 2002.11b
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    • pp.283-285
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    • 2002
  • The paper describes a study of selection of existing a.c. Transmission facilities converted fur use with d.c. system. In order to increasing the power transfer capability of existing a.c. transmission facilities, d.c. is one of good alternatives. Some advantages and disadvantages of this method are discussed, and the selection method of existing transmission facilities for use with d.c. considering economics and stability is presented in this paper.

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Analysis on the Interference Effects between HAPS and NGSO Systems in the Feeder Link (HAPS와 NGSO 시스템의 Feeder Link상의 간섭분석)

  • 문승영;김봉석;강영흥
    • Proceedings of the Korea Electromagnetic Engineering Society Conference
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    • 2000.11a
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    • pp.34-38
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    • 2000
  • In this paper, interference effects between NGSO and HAPS in the feeder link have been simulated and analyzed by means of calculating excess time percent and duration below the C/I protection ratio. As the results, in the case of HAPS interference into NGSO, it can be obtained that the lowest C/I values are 27.42dB in 50km and 12.73dB in 20Km of HAPS altitudes, respectively. And in the case of NGSO interference into HAPS, it can be obtained that the lowest C/I values are 13.94dB and 10.42dB respectively. HAPS system has more interference reception from other systems or effects more interference into other systems as its altitude is lower. Also, the lowest C/I values are appeared at difference time with its altitude.

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Bleaching of Oak Kraft Pulp by O, Eo and C/D Stage (O, Eo 및 C/D단계를 이용한 신갈나무 크라프트펄프표백)

  • 김동호;백기현
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.29 no.3
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    • pp.43-50
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    • 1997
  • The purpose of this study was to decrease pollutants of effluents from KP bleaching. Multistage bleaching that combined with O, Eo, and C/D stage was conducted, after optimum bleaching conditions of O, Eo, and C/D stage were determined. Moreover the properties for bleached pulps and pollution level of bleaching effluent were measured by each standard method. Due to increase on the brightness and delignification of pulps by O, Eo, and C/D stage bleaching. It was possible that bleaching sequences were reduced from five stage to four stage. In addition to, OC/DEoD and OC/DEopD bleaching sequences had higher brightness than CEDED bleaching sequence. The pulps bleached by O and Eo stage had higher in tensile index than conventional bleaching sequences with the similar results in burst and tear index. While each bleaching sequences had little differences, bleaching sequences with Eo stage had higher in physical properties than with Eop stage. The pollution level measured by Chemical Oxygen Demand(COD), Biochemical Oxygen Demand(BOD) and Color of bleaching effluents were much lower in combined bleaching sequences of O, Eo and C/D stage than that of CEDED sequence. Particularly, a pollution index of bleaching effluents generated by C/DEoDEB and OC/DEopDED bleaching sequences were lower than that from the other bleaching sequences.

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The Effect of Sea Tangle Supplementation and Exercise Training on Blood Glucose and Lipid Profile in Rats (다시마 보충과 운동훈련이 흰쥐의 혈당과 혈중지질에 미치는 영향)

  • Hwang, Hye-Jin;Kwak, Yi-Sub;Kim, Hyang-Suk;Choi, Yung-Hyun;Kim, Byung-Woo;Kwon, Hyun-Ju;Yoon, Byung-Kon
    • Journal of Life Science
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    • v.20 no.5
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    • pp.805-810
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    • 2010
  • The purpose of this study was to investigate the effect of Sea Tangle supplementation and exercise training on blood glucose and lipid profile in rats. Twenty seven, 4-week old male Sprague-Dawley rats were divided into the control group (C, n=9), sea tangle group (D, n=9) and sea tangle+exercise group (D+T, n=9). Exercise training was performed 5 days a week using a treadmill running program for 6 weeks (5 m/min, 0% grade, 30 min). There was no difference in blood glucose (C: $175.9{\pm}47.5$, D: $173.9{\pm}34.0$, D+T: $165.0{\pm}38.0\;mg/dl$) and triglyceride (C: $251.1{\pm}91.8$, D: $215.0{\pm}90.0$, D+T: $200.0{\pm}89.3\;mg/dl$) among the groups. Total cholesterol value of the D+T group ($81.8{\pm}11.2\;mg/dl$) was significantly lower than that of the C ($103.0{\pm}13.5\;mg/dl$) and D ($102.1{\pm}14.5\;mg/dl$) groups. High density lipoprotein cholesterol (HDL-C) was significantly high in the D+T ($40.9{\pm}9.7\;mg/dl$) group compared with the C ($32.6{\pm}3.8\;mg/dl$) group and D ($31.7{\pm}7.3\;mg/dl$) group. The value of low density lipoprotein cholesterol (LDL-C) for the D ($98.0{\pm}41.0\;mg/dl$) group was statistically lower than the C($114.5{\pm}41.8\;mg/dl$) group, and higher than the D+T ($91.2{\pm}41.7\;mg/dl$) group. In conclusion, sea tangle injection and exercise had a positive effect on blood lipid profiles.

Enrichment of Vitamins $D_3$, K and Iron in Eggs of Laying Hens

  • Park, S.W.;Namkung, H.;Ahn, H.J.;Paik, I.K.
    • Asian-Australasian Journal of Animal Sciences
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    • v.18 no.2
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    • pp.226-229
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    • 2005
  • An experiment was conducted to produce eggs enriched with vitamins $D_3$, K and iron in eggs. Six hundred 97-wk-old ISA Brown force molted hens were allocated to completely randomized block arrangement of six dietary treatments: T1; control (C), T2; C+4,000 IU vitamin $D_3$+2.5 mg vitamin K+100 ppm Fe, T3; C+8,000 IU vitamin $D_3$+5.0 mg vitamin K+100 ppm Fe, T4; C+12,000 IU vitamin $D_3$+7.5 mg vitamin K+100 ppm Fe, T5; C+16,000 IU vitamin $D_3$+10.0 mg vitamin K+100 ppm Fe, T6; C+20,000 IU vitamin $D_3$+12.5 mg vitamin K+100 ppm Fe. Fe was supplemented with Fe-methionine. Each treatment consisted of five replicates of ten cages with two birds per cage. Egg production and egg weight were highest in T2 and incidence of soft and broken egg was highest in T6. Haugh unit was not different among treatments although it tended to be increased as dietary vitamins $D_3$ and K increased. Eggshell strength was not different among treatment. Concentrations of vitamin $D_3$ and K in egg yolk increased and plateaued approximately 20 days after feeding supplemented diets. The level of these vitamins peaked at 12,000 IU/kg vitamin $D_3$ and 7.5 mg/kg vitamin K supplementation and then decreased at the higher than these supplementation levels. The peak concentrations of vitamin $D_3$ and vitamin K were 4.6 times and 4.8 times greater than the control, respectively. Supplementary Fe also increased Fe content in egg yolk. It is concluded that vitamin $D_3$ and K in eggs can be effectively enriched by proper supplementation time and level of these vitamins.

Friedewald-Estimated Versus Directly Measured LDL-Cholesterol: KNHANES 2009-2010 (LDL-콜레스테롤의 Friedewald 계산값과 실측값 비교: 국민건강영양조사 2009-2010)

  • Jang, Sungok;Lee, Jongseok
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.8
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    • pp.5492-5500
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    • 2015
  • Low-density lipoprotein cholesterol (LDL-C) is a major modifiable risk factor for cardio- cerebrovascular disease. In clinical practice, however, it is primarily calculated using the Friedewald formula as a cost-effective method. The aim of this study was to compare Friedewald-estimated and directly measured LDL-C values and assess the concordance in guideline LDL-C risk classification between the two methods. The data were derived from the 2009 and 2010 Korea National Health and Nutrition Survey (KNHANES). Analysis was done for 4,319 subjects with lipid panels-total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), directly measured LDL-C using an enzymatic homogeneous assay, and triglycerides (TG). For subjects with TG lower than 400 mg/dL, Friedewald-estimated and directly measured LDL-C were highly correlated (r = 0.958, p < 0.001) and overall concordance was 82.7%. As TG increased, overall concordance decreased. Overall concordance was 85.4% at TG lower than 150 mg/dL; 78.2% at TG of 150-199 mg/dL; and 71.4% at TG of 200-399 mg/dL. The Friedewld equation tended to overestimate LDL-C when TG are of < 150 mg/dL; however, underestimate LDL-C when TG are of ${\geq}150mg/dL$. As a result, Friedewald estimation misclassified 382 subjects (9.1%) in a higher category versus 348 subjects (8.3%) in a lower category. Our findings suggest that overestimation of LDL-C by the Friedewald formula can be a great problem as well as underestimation.

THE STUDY ON THE NOISE IN THE VESSEL -Effect of the Noise Control by the Noise Arresting Rooms- (선박소음에 관한 연구 -방음실에 의한 소음제어효과실험-)

  • PARK Jung-Hee
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.9 no.3
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    • pp.215-221
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    • 1976
  • In this study, noise arresting effect of the noise control room from the transmission of surrounding noise was tested when the packing noise control rooms were set up in the test room in which the prerecorded noise from an engine room was reradiated at the same level as the original pressure. The inner space of control room A is $3.389m^3(1.19\times1.19\times2.14m)$ having walls furnished with plywood board 9mm in thickness and noise control room door$(60\times45cm) $ and illumination lamp are placed. In case of the control room B, noise absorption board(10mm fiber board which holds the corntype concavity with diameter of 5mm, depth 5mm, space 15mm) is adhered to the internal ceiling and styrol foam boards(20mm) to the walls. The other struction is same as the control room A. Type C is the same as B except wool board(Glass Fiber, 33mm) on the walls. Type D is same as type A except that the thickness of wall is 12mm and wood pyramid type cone$(5\times5\times13cm)$ is adhered to the ceiling ana walls(Fig. 1). When the recorded noise and vibrated noise were controlled in various levels. The noise pressure which passed through the control rooms was measured by sound level meter(Bruel & Kjar 2205, measuring range 37-140dB). In order to calculate the absorption rate in the control rooms the noise pressure was measured at different distances when the recorded noise pressure was radiated. The followings are the results obtained from the experiment. 1. When the noise pressure of the test room was 60dB, transmission rate of type A was $69.7\%$ and increased $3.3\%$ per 10dB. At the same condition, the rate was $53.9\%$ and increased $4.5\%$ per 10dB in type D. Type D was the most effective in noise arresting of the four and the effect was D,C,B and A in order(Fig.2). 2. When the oscillator sound and vessels noise were radiated in 1,000Hz, at one meter distance to the type A and D, the oscillator sound pressure were 77dB and 73dB, while the vessels noise pressure were 73.3dB and 66.2dB respectivley(Fig.3). 3. Refering to the influence of the frequency to the lower oscillator sound(1,000Hz) pressure, both type C and D were almost same at 140cm but type C was 0.3dB lower than type D at 20cm distance(Fig.4).

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CAUCHY-RASSIAS STABILITY OF A GENERALIZED ADDITIVE MAPPING IN BANACH MODULES AND ISOMORPHISMS IN C*-ALGEBRAS

  • Shin, Dong Yun;Park, Choonkil
    • Journal of the Chungcheong Mathematical Society
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    • v.24 no.4
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    • pp.617-630
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    • 2011
  • Let X, Y be vector spaces, and let r be 2 or 4. It is shown that if an odd mapping $f:X{\rightarrow}Y$ satisfies the functional equation $${\hspace{50}}rf(\frac{\sum_{j=1}^{d}\;x_j} {r})+\;{\sum\limits_{\iota(j)=0,1 \atop {\sum_{j=1}^{d}}\;{\iota}(j)=l}}\;rf(\frac{\sum_{j=1}^{d}{(-1)^{\iota(j)}x_j}}{r}) \\({\ddag}){\hspace{160}}=(_{d-1}C_l-_{d-1}C_{l-1}+1)\;{\sum\limits_{j=1}^{d}\;f(x_j)}$$ then the odd mapping $f:X{\rightarrow}Y$ is additive, and we prove the Cauchy-Rassias stability of the functional equation in Banach modules over a unital $C^*$-algebra. As an application, we show that every almost linear bijection $h:{\mathcal{A}}{\rightarrow}{\mathcal{B}}$ of a unital $C^*$-algebra ${\mathcal{A}}$ onto a unital $C^*$-algebra ${\mathcal{B}}$ is a $C^*$-algebra isomorphism when $h(2^nuy)=h(2^nu)h(y)$ for all unitaries $u{\in}{\mathcal{A}}$, all $y{\in}{\mathcal{A}}$, and $n=0,1,2,{\cdots}$.