• Title/Summary/Keyword: hartmann

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A Study on The Effect of Humidity and Temperature of Hydroxy Propyl Methyl Cellulose Dust (Hydroxy Propyl Methyl Cellulose 분진의 습도와 온도에 대한 영향성 연구)

  • Lim Woo-Sub;Mok Yun-Soo;Choi Jae-Wook
    • Journal of the Korean Society of Safety
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    • v.19 no.3 s.67
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    • pp.65-69
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    • 2004
  • This study was performed with Hartmann type dust explosion apparatus and Godbert-Greenwald furnace apparatus in order to research the effect of temperature and humidity affecting LEL, minimum ignition temperature of Hydroxy Propyl Methyl Cellulose. The experimental determinations in the range between $20^{\circ}C\;and\;60^{\circ}C$ of temperature was not affected $LEL(180g/m^3)$ but LEL showed $200g/m^3\;and\;250g/m^3\;at\;80^{|circ}C\;and\;100^{\circ}C$. As the change of humidity LEL was $180g/m^3\;for\;50\%,\;200g/m^3\;for\;60\%\;and\;250g/m^3\;for\;70\%$ but dust explosion didn't occur over $80\%$. The ignition temperature of HPMC dust clouds was increased as increasing of humidity. So, the minimum ignition temperatures at $50\%,\;60\%,\;70\%\;80\%$ of humidity was $363^{\circ}C,\;375^{\circ}C,\;397^{\circ}C,\;405^{\circ}C$.

A Study of Optical Properties of Intraocular Lenses and of Measurement of the Index of Reflection for an Unknown Liquid

  • Joo, Won Don;Jung, Mee Suk
    • Journal of the Optical Society of Korea
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    • v.16 no.3
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    • pp.236-242
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    • 2012
  • In general, such methods as interferometers or wavefront sensors are commonly used for testing of an optical system and optical components. In these cases, the surrounding environments are unlikely to affect the measurements. On the other hand, intraocular lenses of hydrophilic materials with special properties experience a certain difficulty in testing the optical properties. An intraocular lens is dried in the air, which causes deformation and changes the optical characteristics such as index of refraction and thickness. Thus, it is hard to measure the optical characteristics of an intraocular lens by using common methods. In this study, a special structure is used for measuring of the transmission wavefront aberration and effective focal length of an intraocular lens of hydrophilic materials by using a Shark-Hartmann sensor among the various measuring methods. As an application of this measuring method, this study shows a simple method to measure the index of refraction of unknown liquids with a plano-convex lens with a well known index of refraction. Also, this method is used to measure the optical properties of a plano-convex such as index of refraction and curvature by using a liquid with a well known index of refraction.

Experimental Preservation of Isolated Rabbit Lung for Transplantation (이식을 위한 가토 적출 폐의 실험적 보존 방법)

  • 김수현;김송명
    • Journal of Chest Surgery
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    • v.29 no.9
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    • pp.931-939
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    • 1996
  • An experimental comparative study was done to determine the protective effects of three preservation solutions on isolated rabbit heart-lung bloc during acute ischemia and reperfusion of the lung during lung transplantation. Thirty Isolated rabbit heart-lung blocs were divided into 3 groups , group I(n:9) was preserved with Hartmann's solution, group II(n: 10) with modified University of Wisconsin solution, and group III(n: 1 1) with Kosin solution. The isolated heart-lung blocs were washed with Hartmann's so ution. Aftar infusion of each preservation solution into pulmonary artery, the heart-lung bloc was stored at 4'c cold preservation solution for each group for 4 hours and .then the heart-lung blocs were reventilated and reperfused. The changes of weight of heart-lung blocs, airway pressure, percent change of PCO2, level of lactate and adenosine deaminase(ADA) and microscopic structure of the lung parenchyme were evaluated. Results were as follows 1. A change of weight of the heart lung bloc after reperfusion was lowest in group 111(p< .05) 2. The airway pressure increased after reperfusion in group I but decreased in group II, and II. Especially in group II, post-reperfusion airway pressure returned to level lower than that of en-bloc resection. 3. Pulmonary artery pressure during reperfusion after 4 hour preservation was lowest in group III, and pulmonary artery pressure in group II was higher than in group I(P> 0.1). 4. The level of lactate and ADA in the lung tissue were higher in group III than in group I and II(P< .05) 5. The percent change of PCO2 in perfusate was slightly higher in group III than group I and II. 6. Microscopic changes in lung tissue after reperfusion were diffuse pulmonary edema, expansion of inter- stitial tissue, focal aggregation of erythrocytes, and basement membrane abnormalities, but no differences were found among the three groups. In conclusion, the protective effects of modified University of Wisconsin solution and Kosin solution were slightly superior to Hartmann's solution.

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The Effect of Myopic Degree on the Change of Higher-order Aberrations Induced by Aging (근시도가 나이에 따라 유발되는 고위수차의 변화에 미치는 영향)

  • Ryu, Nam-Yul;Park, Kyoung-Hee;Kim, So-Ra;Park, Mi-Jung
    • Journal of Korean Ophthalmic Optics Society
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    • v.19 no.3
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    • pp.353-362
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    • 2014
  • Purpose: The present study was aimed to investigate the change of higher-order aberrations induced by aging and the effect of myopic degree on the correlation between age and higher-order aberrations. Methods: The higher-order aberrations in 931 eyes aged from 20 to 60 were measured by using a LADARWave device employing Hartmann-Shack system to analyze the effect of myopic degree measured by manifest refraction test on higher-order aberrations. Results: Coma and vertical coma aberrations were significantly decreased by the increase of myopic degree while vertical astigmatic aberration was significantly increased. The correlations of age and coma, vertical coma, spherical, vertical trefoil, horizontal trefoil, vertical astigmatic, horizontal astigmatic and vertical tetrafoil aberrations depended on the myopic degree, except for horizontal coma and horizontal tetrafoil aberrations. Conclusions: It is suggested to consider the myopic degree for the refractive correction including the laser surgery based on the present result that higher-order aberrations are affected by the myopic degree.

Effects of Starvation and Perioperative Fluid Therapy on the Blood Glucose Concentrations during Anesthesia in Children (소아마취시 금식과 수액투여가 혈당농도에 미치는 영향)

  • Suh, Ill-Sook;Song, Sun-Ok;Park, Dae-Pal
    • Journal of Yeungnam Medical Science
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    • v.1 no.1
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    • pp.89-93
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    • 1984
  • This study included 38 children patients of less than 4 years old and 18kg body weight. 93 After 8 hours of starvation, the children were divided into 2 groups: Group I received Hartmann's solution and Group II received Hartmann's dextrose solution. In both groups, the rates of infusion were 10ml/kg/hr before and during operation and blood samples were collected just before and 1 hr after induction of anesthesia, respectively. The results were as follows; 1) In the Group I, blood glucose concentration just before induction was decreased than control values that was checked at ward, and 1 hr values after induction was significantly increased than control values. 2) In the Group II, blood glucose concentration was increased just before and 1hr after induction than control values significantly respectively. 3) In the blood glucose concentration 1 hr after induction, difference between Group I and Group II was not significant. 4) In children, duration of starvation about 8 hrs did not significant influence on blood glucose concentration although dextrose was not administered.

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Modal Control of Adaptive Optical System for Wavefront Correction (파면보정을 위한 적응광학계의 Modal 제어)

  • 서영석;백성훈;박승규;김철중;양준묵
    • Proceedings of the Optical Society of Korea Conference
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    • 2002.07a
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    • pp.32-33
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    • 2002
  • 적응광학계(adaptive optics system ; AO)는 파면을 파면측정장치로 측정하고 제어용 컴퓨터를 사용하여 파면보정장치를 구동함으로써 파면의 왜곡 및 수차를 보정하는 장치로, 최근 천문학 및 의료분야에서 활용되고 있다. 적응광학계의 제어는 파면을 영역별로 나누어 제어하는 zonal 방법과 모드로부터 제어하는 modal 방법이 있다. 본 연구에서는 파면 측정 장치(wavefront sensor ; WFS)인 Shack-Hartmann sensor로 측정된 파면의 기울기 정보로부터 Zernike 다항식의 계수를 계산하여 수차의 정보를 구현하고, 왜곡된 파면을 실시간으로 보정하기 위하여 Zernike 계수로부터 위상을 재구성한 후 보정장치인 변형거울을 제어하는 방법으로 파면을 보정하였다. (중략)

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Scolelepis (Scolelepis) kudenovi (Polychaeta: Spionidae) new to Korea

  • Choi, Hyun Ki;Yoon, Seong Myeong
    • Journal of Species Research
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    • v.5 no.3
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    • pp.355-358
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    • 2016
  • A spionid polychaete, Scolelepis (Scolelepis) kudenovi Hartmann-Schroder, 1981, is newly reported from Korean waters with description and illustration. Scolelepis (Scolelepis) kudenovi is characterized by a combination of the following morphological features: the notopodial setae are present on the setiger 1; the occipital tentacle is absent; the branchiae are partially fused to the notopodial postsetal lamellae; the notopodial and neuropodial hooded hooks are bidentate only; the notopodial hooded hooks are present on the posterior setigers. A key to Scolelepis species from Korean waters is provided in this paper.

Two-Parameter Study on the Jet Regurgitant Mode of Resonant Tube

  • Chang, Se-Myong;Lee, Soogab
    • The Journal of the Acoustical Society of Korea
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    • v.19 no.2E
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    • pp.20-26
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    • 2000
  • A conceptual simplified model of Hartmann-Sprenger tube is suggested and investigated to decouple the regurgitant mode in the present paper. In spite of high nonlinearity, the acoustic behavior of this resonant tube system is dependent on wavelength and depth of the tube. The effect of forcing frequency and tube geometry on jet regurgitant mode are studied and discussed. With a conventional axisymmetric Euler code, sensitive acoustic problems are solved and validated by comparison with analytic theories.

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