• Title/Summary/Keyword: 자탄

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Influence of Dietary Activated Coconut Charcoal on Egg Quality and Plasma Cholesterol Level in Laying Hens (산란계에서 활성야자탄의 첨가가 계란의 품질 및 혈장 콜레스테롤 함량에 미치는 영향)

  • 민병준;김인호;이원백;홍종욱;김지훈;권오석;이상환
    • Korean Journal of Poultry Science
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    • v.29 no.1
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    • pp.13-18
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    • 2002
  • This study was conducted to investigate the effects of dietary activated coconut charcoal (ACC) on Performance, e99 quality and Plasma cholesterol level of Plasma in laying hens. One hundred forty four, 47-wk-old, ISA Brown commercial layers were used in a 28-d feeding trial after a 7-d adjustment Period. Four dietary treatments were 0, 0.5, 1.0 and 1.5e% levees of ACC supplemented to a corn-soybean meal basal diet. Egg Production was significantly increased as the levels of ACC increased. However, egg weight was significantly decreased by the addition of ACC in diets. Egg shell breaking strength tended to decrease as the level of ACC increased, however, no significance was found in this respect. As the levels of ACC increased, egg shell thickness decreased significantly. Although not significant, yolk color tended to increase by the addition of ACC. Egg folk index were significantly increased by the addition of ACC In diet. No significant difference was found among four treatments in total cholesterol, HDL cholesterol, and LDL+VLDL cholesterol concentrations in plasma. In conclusion, dietary supplementation of ACC to layer diets could be used to increase egg Production, and yolk index.

다연장로케트 MLRS

  • Kim, Jong-Ho
    • Defense and Technology
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    • no.5 s.87
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    • pp.46-49
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    • 1986
  • 지극히 짧은 시간에 대량의 화력을 발휘하는 다연장로케트. 그 최신형이 MLRS. 자탄, 지뢰, 종말유도자탄을 내장하여 침공제이제대를 저지하는 가장 유효한 무기체계이다.

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Quantitative Analysis of Initial Dispersion Condition Effects on Randomness of Magnus Rotor Bomblet (Magnus Rotor 자탄의 초기 방출조건이 분산도에 미치는 영향에 대한 정량적 분석)

  • Bai, Ikhyun
    • Journal of the Korea Society for Simulation
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    • v.28 no.3
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    • pp.83-89
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    • 2019
  • This research describes quantitative effects of initial dispersion conditions upon the dispersion randomness of Magnus rotor bomblets. Ratios of the missile spin rate to the missile velocity, a, flight path angles, ${\gamma}$ and altitudes, h, were changed to investigate their effects on dispersion randomness. Dispersion was analyzed through calculation of 6 degree of freedom motion equation with aerodynamic coefficients from wind tunnel experiments. In order to analyze the randomness, regression analysis is adopted to calculate the coefficient of determination. The optimized ratio of the missile spin rate to the missile velocity and flight path angle were obtained and the dispersion altitudes had more effect on the dispersion diameter and had less effect on dispersion than other parameters.

Numerical simulation of the aerodynamic characteristics on the grid-fin adapted sub-munition with low aspect ratio under transonic condition (그리드핀을 적용한 작은 세장비를 갖는 자탄의 천음속 공력특성 전산해석)

  • Yoo, Jae-Hun;Kim, Chang Kee;Choi, Yoon Jeong;Lim, Ye Seul
    • Journal of the Korea Society for Simulation
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    • v.28 no.2
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    • pp.23-33
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    • 2019
  • A sub-munition which has low aspect ratio does not have flight stability and control of drag force under free-fall condition. In order to satisfy those problems, fin, which is called grid-fin, is designed instead of conventional flight fins and adapted to the sub-munition. The base model of the sub-munition is firstly set and numerical simulation of the model is conducted under transonic condition that is free-fall range of the sub-munition. Wind test is secondly performed to verify the simulation result. The result shows that grid fin adapted sub-munition has high drag force, but the flight stability is still needed. In order to enhance the flight stability, two additional grid-fins are designed which modify web-thickness and numerical simulations of modified models are conducted. As the results, the thinnest web-thickness grid-fin has the highest flight stability and still maintains high drag coefficient. Based on these results, design of grid-fin adapted sub-munition is completed, the path trajectory of the sub-munition can be predicted with acquired aerodynamic datum and it is expected that grid fin can be used to various shape of the flight vehicle and bomb.

Pharmacological Profile of KR-31125, an Orally Active AT1 Receptor Antagonist (안지오텐신 수용체 리간드 KR-31125의 생체 내 활성에 관한 연구)

  • Lee, Sung-Hou
    • Journal of Life Science
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    • v.20 no.7
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    • pp.969-976
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    • 2010
  • In vivo studies of KR-31125 (2-butyl-5-dimethoxymethyl-6-phenyl-7-methyl-3-[[2'-(1H-tetrazol-5-yl) biphenyl-4-yl]methyl]-3H-imidazo[4,5-b]pyridine) were performed in pithed rats, conscious angiotensin II (AII) challenged normotensive rats, renal hypertensive rats (RHRs) and furosemide-treated beagle dogs. KR-31125 induced a non-parallel right shift in the dose-pressor response curve to AII ($ID_{50}$: 0.095 mg/kg) with a dose-dependent reduction in the maximum responses in pithed rats. Compared to losartan, this antagonistic effect was about 18 times more potent, presenting competitive antagonism. Other agonists such as norepinephrine and vasopressin did not alter the responses induced by KR-31125. Orally administered KR-31125 had no agonistic effect and dose-dependently inhibited the pressor response to AII with a slightly weaker potency ($ID_{50}$: 0.25 and 0.47 mg/kg, respectively) in the AII-challenged normotensive rat model, but with a more rapid onset of action than losartan (time to $E_{max}$: 30 min for KR-31125 and 6 hr for losartan). KR-31125 produced a dose-dependent antihypertensive effect with a higher potency than losartan in RHRs, and these effects were confirmed in furosemide-treated dogs where they presented a dose-dependent and long-lasting (>8 hr) antihypertensive effect with a rapid onset of action (time to $E_{max}$: 2-4 hr), as well as a 20-fold greater potency than losartan. These results suggest that KR-31125 is a potent, orally active $AT_1$ receptor antagonist that can be applied to the development of new diagnostic and research tools as an added exploratory potential of $AT_1$ receptor antagonist.

A STUDY ON AERODYNAMIC ANALYSIS OF A SUB-MUNITION WITH DRAG RIBBON (항력리본이 장착된 자탄의 공력 해석 연구)

  • Kang, Seung-Hee;Kim, Jin-Suk;Ahn, Sung-Ho
    • Journal of computational fluids engineering
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    • v.16 no.4
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    • pp.14-20
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    • 2011
  • The initial unfolding motion simulation of a sub-munition with drag ribbon for precision guidance and reliable operation has been investigated by analyzing its unsteady aerodynamic load and fluid structure interaction. The effects of change in the ribbon configuration and flow angle are numerically studied using a commercial software "XFLOW" based on Lattice-Boltzmann Method. It is shown that the motion is affect adversely by the separation bubble formed posterior part of the fuselage. The rolling moment for arming of the sub-munition is increased with angle of attack and rotational movement.

Simulation and Analysis of Top-Attack Smart Submunition Descent Motions and Target Searching Footprint (상부공격 지능자탄의 낙하운동 및 탐색경로 시뮬레이션)

  • Kim, Ki-Pyo;Chang, Kwe-Hyun;Choi, Sang-Kyung;Hong, Jong-Tai
    • Journal of the Korea Institute of Military Science and Technology
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    • v.11 no.6
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    • pp.5-13
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    • 2008
  • A smart submunition drops through the expected trajectory to have a appropriate target searching footprint for the armored ground vehicles. Parachutes can be used as a tool to decelerate and spin the submunition. Usually submunition's descent velocity, spin rate, submunition inclination angle against vertical and dynamic stability affect to its target searching footprint. Therefore it is important to design optimal parachute and load configuration for the overall system performance. In this paper we described the dynamic motion of submunition by the mathematical model of parachute and load. Through the computer simulation we can analyze the submunition footprint affected by parachute and load design.