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SELF-PREPARATION OF BATHYTHERMOGRAPH SMOKED-GLASS SLIDE (Bathythermograph Smoked-glass slide의 간역제작법)

  • HUE Jong Soo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.1 no.2
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    • pp.135-137
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    • 1968
  • Bathythermograph (B. T) has been coumonly used to obtain a records of water temperature in the depth of 270m from the surface. We have, however, experienced some difficulties in obtaining smoked or coated glass which is used for the bathythermograph in this region, Therefore I introduce a easy method of preparing the smoked-glass slide. Preparing method is as follows. 1. Glass slides must be cleaned by dipping into the concentrated solution of sodium hydroxide ana hydrochloric acid then rinsing with hot water and polishing with a clean gauge. 2. The cleaned slide is immersed in the wax solution for coating, and dried on the filter paper. The Wax solution is prepared as follow : 1g of white wax is dissolved in 200CC of benzol or 1g of lard is dissolved in 300CC of gasoline. 3. A slide held in a fingertip is smoked on the flame of alcohol lamp, or Meter burner. When alcohol lamp is used the fuel alcohol must contain 1/5 of benzol, and when Meker burner is used, the air intake must be blocked up. The smoking on the glass slide should be light and uniform, after smoking the slide is cooled down. 4. The smoked glass slide is again dipped into the wax solution using a fingertip and the excessive wax solution on the slide is absorbed on the filter paper and drain off. 5. Thus prepared smoked slide can be used for B.T.

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Compatibility Study of Excipients for Pravastatin Tablet (Pravastatin 정제 연구를 위한 첨가제와의 적합성 연구)

  • Kim, Kang Min
    • Journal of Life Science
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    • v.28 no.4
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    • pp.472-477
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    • 2018
  • Pravastatin sodium is a 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitor used in the treatment of hypercholesterolemia by reducing cholesterol biosynthesis. Pharmaceutical excipients of commonly used including water, diluents, stabilizers, disintegrants, lubricants and colorants, and were identified for compatibility. All tests were performed by means of physical mixture of pravastatin and the excipients, which were placed in a press-through-pack (PTP) and incubated under accelerated conditions ($40^{\circ}C$ and 75% relative humidity) for 3 months. The blends of pravastatin with all excipients developed white, off white, and light brown powders, which showed no changes upon visual analysis. Accelerated conditions changed the degradation profile of pravastatin calcium in the HPLC system when mixed with different excipients. Although most excipients can have minor effects on pravastatin stability, the major degradation product from pravastatin was lactone. Low-level interaction (assay and impurity) was induced by all excipients except for microcrystalline cellulose and croscarmellose sodium. These excipients increased lactone impurity in 3 months by as much as 0.22% and 0.18% respectively. The total mixture slightly increased the lactone impurity (by 0.43% in 3 months) of pravastatin. There was no change in the assays of all excipients. These results will be helpful in studying tablet size reductions for convenience of use.

Study on the Prediction of Lateral and Yawing Behaviors of a Leading Vehicle in a Train Collision (철도차량 충돌 시 선두차량의 횡 및 요잉 거동 예측 연구)

  • Kim, Jun Woo;Jeong, Eui Cheol;Koo, Jeong Seo
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.41 no.2
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    • pp.95-101
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    • 2017
  • In this study, we derived theoretical equations for the zigzag movement of a leading vehicle, which is the most frequent behavior in train accidents, by using a simplified spring-mass model for the rolling stock. In order to solve the equations of motion, we applied the Runge-Kutta method, which is the typical numerical analysis method used for differential equations. Furthermore, the lateral displacement of the wheel-set at the wheel-rail interface was estimated using kinetic energy. In order to verify the derived equations, we compared the theoretical and simulated results under various collision conditions. The maximum relative deviations of the lateral displacements were 0.8 [%] ~ 4.7 [%] in light collisions and 0.6 [%] ~ 5.1 [%] under derailment conditions. When an accident is simulated, these theoretical equations can be used to predict the overall behavior and obtain the offset of the body-to-body link as the initial perturbation.

Evaluation of the Radiation Pneumonia Development Risk in Lung Cancer Cases

  • Yilmaz, Sercan;Adas, Yasemin Guzle;Hicsonmez, Ayse;Andrieu, Meltem Nalca;Akyurek, Serap;Gokce, Saban Cakir
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.17
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    • pp.7371-7375
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    • 2014
  • Background: Concurrent chemo-radiotherapy is the recommended standard treatment modality for patients with locally advanced lung cancer. The purpose of three-dimensional conformal radiotherapy (3DCRT) is to minimize normal tissue damage while a high dose can be delivered to the tumor. The most common dose limiting side effect of thoracic RT is radiation pneumonia (RP). In this study we evaluated the relationship between dose-volume histogram parameters and radiation pneumonitis. This study targeted prediction of the possible development of RP and evaluation of the relationship between dose-volume histogram (DVH) parameters and RP in patients undergoing 3DCRT. Materials and Methods: DVHs of 41 lung cancer patients treated with 3DCRT were evaluated with respect to the development of grade ${\geq}2$ RP by excluding gross tumor volume (GTV) and planned target volume (PTV) from total (TL) and ipsilateral (IPSI) lung volume. Results: Were admitted statistically significant for p<0.05. Conclusions: The cut-off values for V5, V13, V20, V30, V45 and the mean dose of TL-GTV; and V13, V20,V30 and the mean dose of TL-PTV were statistically significant for the development of Grade ${\geq}2$ RP. No statistically significant results related to the development of Grade ${\geq}2$ RP were observed for the ipsilateral lung and the evaluation of PTV volume. A controlled and careful evaluation of the dose-volume histograms is important to assess Grade ${\geq}2$ RP development of the lung cancer patients treated with concurrent chemo-radiotherapy. In the light of the obtained data it can be said that RP development may be avoided by the proper analysis of the dose volume histograms and the application of optimal treatment plans.

Laser Speckle Imaging Using Adaptive Windowing Method (적응 윈도우 기법을 사용한 레이저 스펙클 영상의 처리)

  • Jin, Ho-Young;Shin, Hyun-Chool
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.47 no.1
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    • pp.97-102
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    • 2010
  • A laser speckle is a random pattern that has a granular appearance produced by reflected light when a coherent laser illuminates an irregular course surface. Most important property of laser speckle is detecting micro-vascular. Speckle image needs image processing to detect micro-vascular. This paper proposes a new image processing method for laser speckle, adaptive window method that adaptively processes laser speckle images in the spatial. Conventional fixed window based LASCA has shortcoming in that it uses the same window size regardless of target areas. Inherently laser speckle contains undesired noise. Thus a large window is helpful for removing the noise but it results in low resolution of image. Otherwise a small window may detect micro vascular but it has limits in noise removal. To overcome this trade-off, we newly introduce the concept of adaptive window method to conventional laser speckle image analysis. We have compared conventional LASCA and its variants with the proposed method in terms of image quality and processing complexity.

Studies on the method for promoting the germination of sod seed (잔디종자의 발아촉진에 관한 연구)

  • Jae-Young Cho;Bong-Ku Kim
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.4 no.1
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    • pp.125-129
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    • 1968
  • For the study of method for promoting the germination of Korean sod seeds harvseted newly some physical and chemical treatments were tested in this experiment. The summarized results of these tests are as follows: 1. Storage of wet seed in low temperature of 0~$2^{\circ}C$ during 2~30 days was seemed the most effective treatment for promoting the germination of sod seed. 2. The treatment that Soaking and mixing up the seeds in cone sulphuric acid about one and half minutes and then washing off in the water promoted fairly the germination of sod seeds. 3. Better germination of sod seeds was found in the light than in the dark or soil. 4. Cutting the top of seed and crushing of seed coat with sand seemed to promote slightly the germination of sod seeds. 5. No promoting effect for germination of sod seeds was found with treatments of Gibberellin, $NH_4$ $NO_3$ and NAA.

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SPECTROSCOPIC AND PHOTOMETRIC STUDY OF STARBURST GALAXIES: OPTICAL AND NEAR INFRARED PROPERTIES OF A BLUE COMPACT DWARF GALAXY MRK 49 IN THE VIRGO CLUSTER

  • Sung, Eon-Chang;Kyeong, Jae-Mann;Byun, Yong-Ik
    • Journal of The Korean Astronomical Society
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    • v.41 no.5
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    • pp.121-137
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    • 2008
  • We present optical and near-infrared imaging and long-slit spectroscopy for the blue compact dwarf galaxy (BCD) Mrk 49 in the Virgo Cluster. The surface brightness distribution analysis shows that Mrk 49 consists of an off-centered blue bright compact core of r = 10" and a red faint outer exponential envelope. The $H_{\alpha}$ image and color difference suggest that these two components have different stellar populations: a high surface brightness population of massive young stars and an underlying low surface brightness population of older stars. The redder near-infrared colors of the inner most region suggest that the near-infrared flux of Mrk 49 originates from evolved massive stars associated with the current star-forming activity. The total apparent magnitude is $B_T\;=\;14.32$ mag and the mean effective surface brightness is ${\mu}_{eff}(B)\;=\;21.56$ mag $arcsec^{-2}$. Long-slit spectroscopy shows that Mrk 49 rotates apparently as a solid body within r = 10" in a plane at position angle 55 degrees with an amplitude of about $20\;km\;sec^{-1}$. The measured radial velocity of Mrk 49 was derived as $1,535\;km\;sec^{-1}$; and the total mass of stars and gases is in the range of 3 to $6\;{\times}\;10^9\;M_{\odot}$. The mass-to-light ratios for the central region of Mrk 49 in I and B band are estimated 1.0 and 0.5, respectively. The upper limit of the dark matter to visible matter ratio seems to be < 5. The oxygen abundance is $12\;+\;\log(O/H)\;=\;8.21\;{\pm}\; 0.1$ which is about one quarter of the solar value while the relative helium abundance appears to be similar to that of the sun.

A Fast-Switching Current-Pulse Driver for LED Backlight (LED 백라이트를 위한 고속 스위칭 전류-펄스 드라이버)

  • Yang, Byung-Do;Lee, Yong-Kyu
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.46 no.7
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    • pp.39-46
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    • 2009
  • A fast-switching current-pulse driver for light emitting diode (LED) backlight is proposed. It uses a regulated drain current mirror (RD-CM) [1] and a high-voltage NMOS transistor (HV-NMOS). It achieves the fast-response current-pulse switching by using a dynamic gain-boosting amplifier (DGB-AMP). The DGB-AMP does not discharge the large HV-NMOS gate capacitance of the RD-CM when the output current switch turns off. Therefore, it does not need to charge the HV-NMOS gate capacitance when the switch turns on. The proposed current-pulse driver achieves the fast current switching by removing the repetitive gate discharging and charging. Simulation results were verified with measurements performed on a fabricated chip using a 5V/40V 0.5um BCD process. It reduces the switching delay to 360ns from 700ns of the conventional current-pulse driver.

A Study on the Chattering under Cryogenic Flow Test of a Oxidizer Shutoff Valve (산화제 개폐밸브의 극저온 유동시험에서 채터링의 고찰)

  • Lee, JoongYoup;Han, SangYeop;Lee, SooYong
    • Aerospace Engineering and Technology
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    • v.12 no.2
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    • pp.108-117
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    • 2013
  • The oxidizer shutoff valve of a gas generator controls the mass flow rate of the propellant of a rocket engine using pilot pressure and spring the force of the valve. The developing oxidizer shutoff valve can be shut off if the pilot pressure is removed from the actuator. Therefore, force balancing is necessary to analyze the characteristics of the forces with respect to the opening and closing of the valve in order to evaluate its performance. In light of this, the valve has been designed to adjust the control pressure required to open the poppet and to determine the working fluid pressure at which the valve starts to close. Under cryogenic flow test as a tests level of C.R.T(Control Random Test), the chattering phenomena occurred due to much leakage of a metal seat section. The pressure for chattering of the oxidizer valve is predicted at about 11 bar using force balancing analysis.

A Black and White Comics Generation Procedure for the Video Frame Image using Region Extension based on HSV Color Model (HSV 색상 모델과 영역 확장 기법을 이용한 동영상 프레임 이미지의 흑백 만화 카투닝 알고리즘)

  • Ryu, Dong-Sung;Cho, Hwan-Gue
    • Journal of KIISE:Computer Systems and Theory
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    • v.35 no.12
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    • pp.560-567
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    • 2008
  • In this paper, we discuss a simple and straightforward binarization procedure which can generate black/white comics from the video frame image. Generally, the region of human's skin is colored white or light gray, while the dark region is filled with the irregular but regular patterns like hatching in most of the black/white comics. Note that it is not enough for simple threshold method to perform this work. Our procedure is decoupled into four processes. First, we use bilateral filter to suppress noise color variation and reserve boundaries. Then, we perform mean-shift segmentation for each similar colored pixels to be clustered. Third, the clustered regions are merged and extended by our region extension algorithm considering each color of their regions. Finally, we decide which pixels are on or off using by our dynamic binarization method based on the HSV color model. Our novel black/white cartooning procedure was so successful to render comic cuts from a well-known cinema in a resonable time and manual intervention.