• Advances in Traditional Medicine
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• 제7권1호
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• pp.94-99
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• 2007

The present study is aimed at finding the effect of B-20 drops, a homoeopathic formulation, in streptozotocin (STZ) induced diabetic rats. B-20 drops comprises of the constituents derived from plants and other natural sources, and are generally prescribed by the homoeopathic physician, in cases of hyperglycemia and diabetes. The elevated levels of fasting blood glucose and pancreatic lipid peroxides observed in rats treated with STZ were significantly reduced by the treatment of B-20 drops. The reduced liver glycogen contents were also brought back to near normal level by B-20 drops treatment in STZ diabetic rats. STZ induced histopathological changes in pancreas and liver was also partially reversed by B-20 drops. The findings indicate that B-20 drops help in improving the glycogen stores in the liver and prevents STZ induced damage through free radicals by decreasing the pancreatic lipid peroxides levels.

• 한국환경보건학회지
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• 제1권1호
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• pp.14-17
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• 1974

A study was carried out to detect of illegal artificial dyes, and to confirm the used rate of illegal dyes in the production process of commercial drops (candy), from Dec. 10, 1972 to Feb. 10, 1973. In this study, it was used thin layer chromatography, the samples were divided into two groups, group A of inscribed trade name and group B of not inscribed trade name. To contrast with group A and group B, 100 samples were randomly collected in the market places, 50 samples from group A and 50 samples from group B. The following conclusions were obtained: 1) used rate of illegal dyes were 2% of group A and 9% of group B. 2) used rate of illegal dyes were 2% of red, 2% of yellow, 1% of violet and 6% of green, not in blue. 3) used rate of illegal dyes 3% of Rhodamine B, 3% of Auramine and 6% of Light green S.F. Yellowish. 4) Out of 20 cases those used mixed dyes, only one case was confirmed as two illegal dyes, and 4 cases were used one illegal dye.

• 대한기계학회논문집B
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• 제22권11호
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• pp.1499-1508
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• 1998

A numerical study is performed to investigate pressure drops, particle trajectories and erosion around orifice plates in pulverized coal pipe lines. Particle impaction rates change significantly with orifice shapes and Stokes numbers. At Reynolds number of $5{\times}10^5$, the pulverized coal flows well with streamlines and do not collide at the orifice plates at small sizes (${\sim}20{\mu}m$). However, the large particles (over $70{\mu}m$) impact on the front face of the orifice and erode the orifice surface. The pressure loss coefficients around the erode orifice are largely different from the designed original orifice.

• 대한전자공학회논문지SD
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• 제37권12호
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• pp.43-49
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• 2000

본 논문에서는 샘플격자를 이용한 새로운 파장가변형 다채널 OADM(Optical Add/Drop Multiplexers)을 제안하고 그 특성을 살펴보았다. 제안된 새로운 파장가변형 다채널 OADM은 한 개의 샘플격자와 한 개 이상의 FBG를 사용하여 격자의 작은 중심파장이동으로도 여러 개의 채널 중에서 한 개이상의 채널을 동시에 추출할 수 있으며, 이때 인접채널간의 제거비가 20[㏈]이상으로 인접채널간 crosstalk 특성이 매우 우수함을 알 수 있었다.

• 대한기계학회논문집B
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• 제20권12호
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• pp.4053-4061
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• 1996

Internal flow characteristics within Y-jet atomizers and the local drop size distribution and cross-sectional averaged drop size at the outside were investigated with the liquid and air injection pressures, mixing port length of atomizers, and the liquid properties taken as parameters. To examine the effect of the liquid viscosity, glycerin-water mixtures were used in this study. The liquid viscosity plays only a minor role in determining the internal flow pattern and the spatial distribution shape of drops, but the drop sizes themselves generally increase with increasing of the liquid viscosity. An empirical correlation for the liquid discharge coefficient at the liquid port was deduced from the experimental results; the liquid discharge coefficient strongly depends on the liquid flow area at the mixing point which is proportional to the local volumetric quality(.betha.$_{Y}$), and the volumetric quality was included in the correlation. Regardless of the value of the liquid viscosity, the compressible flow through the gas port was well represented by the polytropic expansion process(k=1.2), and the mixing point pressure could be simply correlated to the aspect ratio( $l_{m}$/ $d_{m}$) of the mixing port and the air/liquid mass flow rate ratio( $W_{g}$/ $W_{f}$) as reported in the previous study.udy.udy.y.

• 대한기계학회논문집B
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• 제25권9호
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• pp.1219-1226
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• 2001

Pressure drops were measured for the flow boiling process within horizontal rectangular channels. The gap between the upper and the lower plates of each channel ranges from 0.4 to 2mm while the channel width being fixed to 20mm. Refrigerant 113 was used as the test fluid. The mass flux ranges from 50 to 200kg/㎡s and the channel walls were uniformly heated up to 15kW/㎡. The quality range covers from 0.15 to 0.75. The present experimental conditions coincide with the operating conditions of compact heat exchangers in which the liquid and gas flows are laminar and turbulent. The measured results were well represented by the two-phase frictional multiplier of Lee (2001) which has been developed for air-water two-phase flows within the deviation of $\pm$20%.

• 한국가스학회지
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• 제20권4호
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• pp.50-57
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• 2016

도시가스사업법령에서는 매설된 강관에는 부식을 방지하기 위하여 전기방식 조치를 하도록 하고 있다. 미국 등 국외에서 방식전위기준은 방식전류가 흐르는 상태에서 포화황산동 기준전극으로 -850 mV(On potential) 이하로 하도록 하고 있으며, 이 경우 전압강하(IR-Drop)를 고려하도록 하고 있다. 그러나, 국내의 방식전위 기준은 포화황산동 기준전극으로 -850mV 이하로 하도록 규정하고 있을 뿐, 전압강하를 고려하도록 규정하고 있지 않다. 다만, KGS GC202에서 가스시설에 대한 전위측정은 가능한 한 가스시설과 가까운 위치에서 기준전극으로 실시하도록 하고 있다. 본 연구에서는 기준전극을 매설배관 주위, 지표면 및 지표면 하부 50cm에 각각 설치하여 방식전위를 측정하고, 측정위치에 따른 전위값을 비교하여 전압강하를 분석하였다. 전위 측정결과 기준전극을 매설배관 가까이에 위치하였을 때 IR-Drop이 가장 적고, 지표면에 기준전극을 위치할 때 IR-Drop 값이 가장 큼을 확인하였다. 따라서, 고체기준전극을 매설하는 경우에는 가능한 한 매설배관 가까이에 설치할 것을 제안하였다. 또한, 기존에 설치된 배관의 원격전위 측정을 위해서는 기존에 설치된 전위측정용터미널(T/B) 하부에 고체기준전극을 매설할 수 있도록 전기방식 기준전극 설치 기준 개정(안)을 제시하였다.

• 한국방사선학회논문지
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• 제5권2호
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• pp.59-66
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• 2011

경부 CT검사 시 선속경화인공물(Beam Hardening Artifact)에 의해 제 6번 7번 경추 및 추간판 등의 질환 및 그밖에 해부학적 구조를 정확히 구분하기에 어려움이 있다. 경부 CT검사를 시행할 경우 자세의 변화방법을 적용한 견관절의 방향과 위치에 따른 영상평가 및 커널값의 변화에 따른 영상평가를 통하여 선속경화 인공물의 원인을 알아보고 가장 적절한 검사자세 및 Kernel값을 실험을 통하여 알아보고자 하였다. 경부 CT검사를 위해 내원한 환자 30명(2010년 7월1일 ~ 2010년 12월31일까지 내원한 환자)을 대상으로 Somatom Sensation 16(Siemens, Enlarge, Germany)장비를 이용하였고, workstation은 AW 4.4 version(GE, USA)을 이용하였다. 환자 자세는 견관절의 방향과 위치에 따라 세가지 자세로 변화를 주었으며 양쪽 팔을 편안하게 위치시킨 바로 누운 자세(group N), 왼쪽 팔을 거상 시킨 자세(group S) 그리고 양손을 외 선위(eversion)시켜 최대한 아래로 내리는 자세(group P)로 견관절의 방향을 변화를 주어 스캔을 시행하였고, 두 번째로 영상 재구성 방법을 이용하여 스캔 데이터에 커널값을 B10(very smooth), B20(smooth), B30(medium smooth), B40(medium), B50(medium sharp), B60(sharp), B70(very sharp)로 변화를 주어 재구성 하였다. 검사자세의 변화와 Kernel값의 변화를 주어 얻어진 영상 데이터를 이용하여 각 각의 노이즈 값 측정과 영상평가를 통하여 분석해보았다. 경부 CT검사 시 검사자세는 양손을 외선위(eversion)시켜 최대한 아래로 내리는 자세(group P)로 하며, 커널 값은 B40(medium)또는 B50(medium sharp)으로 재구성할 경우 가장 적절한 자세와 커널값으로 분석되어 임상에 적용 시 매우 유용할 것으로 사료된다.

• 대한기계학회논문집B
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• 제23권7호
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• pp.881-892
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• 1999

Experiment was performed to study the characteristics of pressure drop of multi-channel tubes for automotive condenser using HFC-134a. Single phase liquid and two phase flow pressure drop were measured in one rectangular plain and three micro-fin tubes with 10 channels. Data are presented for the following range of variables: mass flux(200 to $600kg/m^2s$), and inlet saturation pressure of the refrigerant(1.0 and 1.6MPa). For subcooled flow, pressure drops are 10% and 12% higher than that predicted by the Petukhov equation with hydraulic diameter respectively. Two-phase flow pressure drop are compared with the previously proposed correlations, and well predicted by modified correlation that was derived from Traviss correlation. and correlated within -30~+20%. Also experimental data are correlated within -56%~+18% by Webb's prediction method based on the equivalent mass velocity concept originally proposed by Akers et al.

• 대한인간공학회지
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• 제20권2호
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• pp.83-97
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• 2001

Korea has become an aged society according to the UN specifications. The number of the aged population will increase drastically, and the number of single aged people will also increase. Products used in our daily life are manufactured within the normal capabilities of people. Thus, aged people have encountering problems in using them. Numerous products are used in our daily lives. The purpose of this study is to find the acceptable torque for aged people to open the caps of processed food containers. Depending on the size and shape of the opening hand, hand operation has been classified into three categories. A total of one hundred and nine people participated in this study. Fifty nine people in the 20-30 year old range and fifty people in their 60-70's. Results of the study are as follows: 1) For all categories the acceptable cap torque data for the aged people are established. To satisfy 95% of the aged people, it was found that $74N{\cdot}cm$ for type A caps, and $141N{\cdot}cm$ for B type caps. and $214N{\cdot}cm$ for type C were the acceptable torque levels. 2) The appropriate level of torque for opening the cap was found to be 70% of the maximum torque for the aged people.(71.4% for type A. 71.4% for type B. 72.2% for type C). 3) Capabilities of the 70's drops sharply in function related to opening cap (maximum torque, gripping force, and wrist movement range). 4) Among aged subjects, 65.0% for type A, 42.0% for type B, and 68.8% for type C, had difficulties in opening the container caps.