• 산업기술연구
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• 제26권A호
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• pp.109-117
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• 2006

This study is an numerical study of predicting the behavior of anchor embedded in weathered rocks, subjected to uplift loads, about ultimate pullout capacity and the failure mechanism. Factors influencing the behavior of anchors were investigated by reviewing the data about in-situ anchor tests performing numerical modelling with changing the bondage length of anchor, diameter of anchor body and diameter of tenden, and by Correlations between those factors were evaluated to apply them to predict the behavior of anchors. As results of numerical analysis, a linear relationship between bondage length, diameter of anchor body and diameter of tenden with ultimate pullout capacity was obtained on the one hand, from the result of numerical analysis changing the Young's modulus of weathered rock, this parameter was found to inflence to load-displacement and ultimate pullout capacity within the range of 10%, which was mot so significant to affect.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 추계학술대회
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• pp.1598-1603
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• 2004

This paper is an experimental study on the performance characteristic with a variation of capillary diameter and length. The performance characteristic of a refrigeration system is predicted that it is occurring changes of flow pattern and pressure drop in a capillary tube because of reduction of capillary diameter 0.74 to 0.6 mm. The difference between experimental results and analytical results is mainly caused by values of friction factor for using to calculate pressure drop through a small diameter capillary tube under 0.74mm. The experimental equation is derived from capillary tube test data using curve fitting method.

• 대한조선학회지
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• 제3권1호
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• pp.11-18
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• 1966

In a polarized light field, triangular plate bracket specimen of CR-39 with lightening hole were subjected to tension. The variables of the models used in the experiment were taken in the range of length-depth $ratio=0.583{\sim}1.715$, eccentricity of lightening hole from the geometrical center of $bracket=-1/4"{\sim}+1/4"$, and the lightening hole $diameter=1/2"{\sim}2"$. The isoclinics were drawn and from those the stress trajectories were constructed. Then the distributions of boundary stress around the lightening holes were determined from the isochromatic fringe pattern. The conclusions reached in this investigation are as follows: 1. Maximum stresses of the hole boundary are gradually increased when the diameter of the lightning hole increase. 2. Maximum stresses of the lightning hole boundary are decreased gradually when the eccentricity of the lightning hole from the geometrical center of the bracket to the farther side from the free end. 3. If the minimum distances from the free end of the brackets to the lightening hole boundaries are equal, the variation of the maximum stresses are in a small range for the change of lightening hole diameter and its location. 4. When the length-depth ratios are smaller than 0.8, the maximum stresses increase steeply. In the range of $0.8{\sim}1.2$ maximum stresses increase gradually and thereafter increase rapidly when the length-depth ratio of the bracket increase for the same diameter of a lightening hole.

• 동력기계공학회지
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• 제4권3호
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• pp.34-39
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• 2000

Performance data in the literature on air lift pumps have been based primarily on pumps of long length and large diameter (high lift pumps). Since mariculture operations involve pumps of relatively short length and small diameter, performance data are required for efficient operation. To provide such data, an experimental apparatus was designed and fabricated to test all lift pumps from 2.1 to 3.4 cm inside diameter and from 40 to 300 cm in length. Instrumentation was provided to measure water flow rate and air flow rate as well as water temperature, air temperature, and pressure throughout the system. Results from this study correlate well with high lift pump data in that, for a given pump geometry, maximum water flow occurs for a specific air flow rate. Driving the pump with air flows larger or smaller than this optimum flow rate will decrease the pumping rate. The optimum flows are significantly different for low lift pumps compared to high lift pumps. However, the pumping rate for low lift pumps approaches that for high lift pumps with increasing length.

• Journal of the Korean Wood Science and Technology
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• 제24권1호
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• pp.1-10
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• 1996

The frequency distribution diagrams of Korean diffuse-porous woods, 36 families, 75 genera, 145 species, 215 specimens in relation to habit and phenology were analyzed. As the habit character changes from shrub to tree, such quantitative features as vessel frequency, percentage of solitary vessels, length/diameter(L/D) ratio of vessel element decreased but tangential vessel diameter, fiber length/vessel element length(F/V) ratio increased. Qualitative features such as helical vessel wall thickening, diffuse distribution of longitudinal parenchyma, heterogeneous ray composition decreased, while alternate intervessel pits, libriform wood fiber, simple perforations increase. As the phenology character changes from evergreen to deciduous species, such quantitative features as percentage of solitary vessels, vessel element length and L/D ratio decreased but tangential vessel diameter, F/V ratio increased. Diffuse distribution of longitudinal parenchyma, heterogeneous ray composition, and crystals in qualitative features decreased, while alternate intervessel pits, libriform wood fiber, simple perforation of vessel element, ray width and ray height increased.

• 대한치과기공학회지
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• 제6권1호
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• pp.19-26
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• 1984

This Experimental study was performed to study the effect of the heat soaking and the diameter of pattern on the casting ability of three nonprecious alloys manufactured for porcelain-metal restorations, with respect to their ability to reproduce test pieces by casting over a selected range of uniform diameters. Samples of total 60 were constructed and divided into 6 groups according to the two variables, the diameter and the heat soaking. The completed cast samples were examined visually and measured with a caliper calibrated to 0.05mm. The results obtained were as follows: 1. Length cast was significantly related to the diameter to be cast, especially in the case of the marrowest diameter of 230m. 2. Length cast not significantly related to the heat soaking. 3. The completeness of casting was significantly related to the diameter to be cast, particularly in the case of the narrowest diameter of 230m. 4. The completeness of casting was not significantly related to the heat soaking. 5. All of the three nonprecious alloys used for this experiment were significantly different from an ideal alloy in the completeness of casting.

• 펄프종이기술
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• 제42권1호
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• pp.7-12
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• 2010

Morphological characteristics of hemp fiber were investigated using a light microscope in order to provide fundamental data for the use of hemp as a papermaking law material. Phloem of hemp is composed of cortical parenchyma cells and bast fiber with thick walls while xylem is composed of vessel, wood fiber and ray parenchyma cells. Also there are solitary pore and radial pore multiple which exist in diffuse porous pattern. Ray cells consist of uniseriate rays and thin walled ray parenchyma cells. Wood fibers are composed of three types: a large diameter fiber with longer length; a large diameter fiber with shorter length; a small diameter fiber with medium length. Vessel elements are composed of: a medium length one; a longer length one; the one whose both end walls have ligules or tails. Parenchyma cells in xylem and pit parenchyma cells have completely different size and shape. For bast fiber, the average length is about 4.4 mm and the width is about $30.5\;{\mu}m$; for vessel element, $600.0\;{\mu}m$ in length and $493.6\;{\mu}m$ in width; for wood fiber, $1000\;{\mu}m$ and $38.9\;{\mu}m$; for parenchyma cell, $50\;{\mu}m$ and $26.4\;{\mu}m$.

• Journal of Korean Neurosurgical Society
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• 제56권2호
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• pp.91-97
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• 2014

Objective : The purpose of this study was to evaluate demographic and clinical factors affecting the common femoral artery diameter and length, and anatomical relationship between the femoral head and the common femoral artery during angiography. Methods : We retrospectively reviewed 109 femoral angiograms. We collected the clinical data of the patients and estimated the common femoral artery diameter and length. We divided the areas in the angiogram from cephalic to caudal direction (zone 0 to 5). The lowest levels of the inferior epigastric artery loop and points of the common femoral artery bifurcation were checked. Results : The luminal diameter of the common femoral artery was $6.19{\pm}1.20mm$. Height, weight, body surface area, as well as common femoral artery diameter were significantly greater in men than in women (p<0.005). The length of the common femoral artery was $27.59{\pm}8.87mm$. Height, weight and body surface area showed strong positive relationships with common femoral artery diameter. All of the inferior epigastric artery loops were located above the center of the femoral head. The point of common femoral artery bifurcation was above the center of the femoral head in 4.59% of femoral angiograms. Conclusions : Males and patients with a high body surface area have a larger common femoral artery diameter. The cumulative probability of optimal targeting between the lowest margin of the inferior epigastric artery loop and the common femoral artery bifurcation is the highest in zone 3 puncture.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2005년도 Proceedings of The 6th korea-china joint workshop on nuclear waste management
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• pp.258-268
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• 2005

A new approach has been adopted to remove the hot particulates from nuclear facilities, KAERI, South Korea, by using the new compact cyclone train, made of steel ness steel, with optional vortex finder length. Flow rate results showed a dramatic change in removal efficiency, performance was changed with the change of exit tube length. The 15 m/s flow rate was found suitable one for new equipment with the 49 mm optimum exit tube length for 76 mm cyclone body diameter. Results shows the removal efficiency for $1\;{\mu}m$ was more than $65\%$ and for $10\;{\mu}m$ was seen ${\~}97\%$. Over 15 m/s flow rate, was not shown much different in removal efficiency. The removal efficiency increased with the flow rate, and pressure drop. Cut size diameter decrease with the inlet flow rate. Cut size diameter found lowest with 49 mm exit tube length and 15 m/s flow rate. For filters the performance decreased with the inlet velocity increased.

• Asian-Australasian Journal of Animal Sciences
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• 제24권4호
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• pp.449-456
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• 2011

Eighteen different biometric traits in 407 Kankrej cows from their breeding zone, i.e. Palanpur district of Gujarat, India, were recorded and analyzed by factor analysis to explain body conformation. The averages of body length, height at withers, height at shoulder, height at knee, heart girth, paunch girth, face length, face width, horn length, horn diameter, distance between horns, ear length, ear width, neck length, neck diameter, tail length with switch, tail length without switch and distance between hip bones were $123.44{\pm}0.37$, $124.49{\pm}0.28$, $94.68{\pm}0.30$, $38.2{\pm}0.14$, $162.56{\pm}0.56$, $178.95{\pm}0.70$, $44.09{\pm}0.10$, $15.91{\pm}0.05$, $42.47{\pm}0.53$, $26.07{\pm}0.19$, $13.34{\pm}0.08$, $31.24{\pm}0.12$, $16.10{\pm}0.05$, $50.63{\pm}0.18$, $73.21{\pm}0.32$, $111.62{\pm}0.53$, $89.34{\pm}0.34$ and $17.28{\pm}0.10\;cm$, respectively. The correlation coefficients between different traits ranged from -0.806 (horn diameter and distance between horns) to 0.815 (heart girth and paunch girth). Most of the correlations were positive and significant. Factor analysis with promax rotation with power 3 revealed three factors which explained about 66.02% of the total variation. Factor 1 described the cow body and explained 38.89% of total variation. The second factor described the front view/face of the cow and explained 19.68% of total variation. The third factor described the back of the cow and explained 7.44% of total variation. It was necessary to include some more variables for factor 3 to obtain a reliable estimate of the back view of the cow. The lower communities shown for distance between horns, horn diameter, ear width and neck diameter indicated that these traits did not contribute effectively to explaining body conformation and can be dropped from recording, whereas all other traits are important and needed to explain body conformation in Kankrej cows. The result suggests that principal component analysis (PCA) could be used in breeding programs with a drastic reduction in the number of biometric traits to be recorded to explain body conformation.