• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.53-54
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• 2007

Charged particle type display using particles which have opposite charge and color is based on effect of reversible optical property due to electric field. we designed mask pattern for fabrication of the charged particle type display based on glass substrate and investigated cell gap dependent of driving voltage and selectively driving method. the panel driven by our selectively driving method, we could obtain image which had vary little crosstalk caused by electrical interference and conform the last image maintained by memory effect without additional voltage.

• Proceedings of the KIEE Conference
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• 1993.07b
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• pp.645-647
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• 1993

Surface breakdown characteristics are investigated under metallic-particle contaminated conditions in $SF_6$ gas. The main results show that a rib increases breakdown voltage by a corona stabilization effect and the elongation of discharge path. The breakdown voltage at higher pressures than 4 atm may be estimated on the basis of mean breakdown field strength($E_{BD}$) and discharge length(L) which depend on gas pressure and surface shape.

• Journal of Advanced Marine Engineering and Technology
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• v.29 no.2
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• pp.161-167
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• 2005

The improvements of the propulsive engine efficiencies could reduce the fuel consumption. Therefore. for a marine main diesel engine the substantial increase of stroke bore ratio. so that the engine speed can be significantly reduced in order to increase the Propulsive efficiency. As a typical example. a Sulzer RTA 60C engine has acylinder diameter of 600 mm and each cylinder is capable of delivering 2.369 kW in the speed range 91-114 rpm. In order to Provide basic data for thermal system of marine engine. this work performs an experimental study of heat transfer in a square channel with one rib-roughened wall under sin91e mode of reciprocating oscillation. A selection of heat transfer measurements illustrates the manner by which the reciprocating channel with two opposite heating walls has the higher heat transfer Performance than with four heating wall.

• The Journal of Engineering Geology
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• v.30 no.3
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• pp.237-251
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• 2020

This study examined structural analysis of supports in tunnel and displacement and underground stress of tunnel by measurement, in order to evaluate the performance of high-strength lattice girders developed as a substitute for H-profiles. According to the three-dimensional nonlinear structural analysis results of the tunnel support, the load and displacement relationship between the H-profiles and the high-strength lattice girders showed almost the same behavior, and the maximum load of the high-strength lattice girders were 1.0 to 1.2 times greater than the H-profiles. By the results of the three-dimensional tunnel cross-section analysis of the supports, the axial force was occurred largely in the lower left and right sides of the tunnel, and showed a similar trend to the field test values. In the results of the measurement of the roof settlement and rod extension, the final displacement of the steel arch rib (H-profile) and high-strength lattice girder section in tunnel was converged to a constant value without significant difference within the first management standard of 23.5 mm. According to the results of underground displacement measurement, the final change amount of the two support sections showed a slight displacement change, but converged to a constant value within the first management standard of 10 mm. By the results of measurement of shotcrete stress and steel arch rib stress, the final change amount of the two support sections showed a slight stress change, but converged to a constant value within the first management standard of 81.1 kg/㎠ and 54.2 tonf.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.1
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• pp.143-150
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• 2013

The aim of the pilot study was to evaluate slaughter characteristics and carcass composition of indigenous long fat tailed sheep and Small East African goats purchased from the auction markets slaughtered at 1.5 to 2 yrs of age and 20 kg to 25 kg live weight. The animals were slaughtered according to halal standard procedures. The left half carcasses were jointed into eight wholesale joints, and dissected into muscles, fat and bone, which were weighed separately. Sheep had greater (p<0.05) slaughter BW (22.29 kg vs 20.50 kg) and empty BW (20.17 kg vs 18.67 kg) than goats (p<0.05). Dressing percentages were lower (p<0.001) in sheep than goats when carcass weight was expressed as percentage of slaughter BW (42.31% and 47.15%) and empty BW (46.75% and 51.79%). Sheep carcasses had lower (p<0.001) proportion (66.18% vs 71.64%) of muscles and higher (p<0.001) proportion of fat (7.41% vs 3.44%) than goat carcasses. Sheep had proportionally lighter (p<0.001) shoulder (18.89% vs 22.68%) and heavier (p<0.05) proportion of chump (7.916% vs 6.76%) and main rib (8.12% vs 7.07%). Sheep had more (p<0.001) muscles in the leg (28.83% vs 27.08%) and main rib (7.62% vs 6.36%) than goats. Sheep had less (p<0.001) muscles (20.28% vs 23.56%) in shoulder joints when expressed as percentage of total muscle of carcasses. It is concluded that there are differences in sheep and goat both in terms of carcass and joint yields and composition. The present study also implies that there is need to consider setting different meat cuts and prices for these cuts when one takes into account the differences in muscle distribution within joints in sheep and goats.

• Steel and Composite Structures
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• v.24 no.2
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• pp.249-264
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• 2017

In this paper free linear vibration of lattice composite conical shells will be investigated. Lattice composite conical shell consists of composite helical ribs and thin outer skin. A smeared method is employed to obtain the variable coefficients of stiffness of conical shell. The ribs are modeled as a beam and in addition to the axial loads, endure shear loads and bending moments. Therefore, theoretical formulations are based on first-order shear deformation theory of shell. For verification of the obtained results, comparison is made with those available in open literature. Also, using FEM software the 3D finite element model of composite lattice conical shell is built and analyzed. Comparing results of analytical and numerical analyses show a good agreement between them. Some special cases as variation of geometric parameters of lattice part, effect of the boundary conditions and influence of the circumferential wave numbers on the natural frequencies of the conical shell are studied. It is concluded, when mass and the geometrical ratio of the composite lattice conical shell do not change, increment the semi vertex angle of cone leads to increase the natural frequencies. Moreover for shell thicknesses greater than a specific value, the presence of the lattice structure has not significant effect on the natural frequencies. The obtained results have novelty and can be used for further and future researches.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.41 no.10
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• pp.667-673
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• 2017

We investigated the temperature uniformity in an anode-supported solid oxide fuel cell, using the open source computational fluid dynamics (CFD) toolbox, OpenFOAM. Numerical simulation was performed in three different flow paths, i.e., co-flow, counter-flow, and cross-flow paths. Gas flow in a porous electrode was calculated using effective diffusivity while considering the effect of interconnect rib. A lumped internal resistance model derived from a semi-empirical correlation was implemented for the calculation of electrochemical reaction. The result showed that the counter-flow path displayed the most uniform temperature distribution.

• Asian-Australasian Journal of Animal Sciences
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• v.1 no.1
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• pp.1-5
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• 1988

Ninety feeder steers, predominantly Herefords weighing 280 kg, were assigned at random to each of nine diets: basal (high concentrate); 25 or 50% of untreated rice straw (25- or 50 URS) or ammoniated rice straw (25- or 50 ARS); a 50:50 mixture of URS - alfalfa or ARS - alfalfa replacing a proportion of the basal at 25 and 50%. Animals were slaughtered after 154 or 161 days of feeding. The cattle fed 50% URS had the lowest (P<.05) carcass weight, dressing & external fat thickness, kidney, pelvic and heart fat, rib eye area, marbling score, quality and yield grades, followed by cattle fed 50% ARS, 50% rice straw/alfalfa, and 25% rice straw alone or 25% rice straw/alfalfa mixture. Ammoniation of rice straw improved all measured traits. A 25% substitution of basal diet with untreated or ammoniated rice straw and a 50% substitution with rice straw/alfalfa mixture did not significantly affect carcass traits compared to the basal group. Only 50% ARS and 50% URS cattle showed differences in body composition (P<.05) with lower fat and higher water and protein contents. No significant differences were found in shear value, panel tenderness, connective tissue, juiciness, flavor and overall palatability of meat from steers fed the basal, ARS or URS diets.

• 한국전산유체공학회:학술대회논문집
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• 2008.03b
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• pp.117-120
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• 2008

Numerical simulations and experiment of a hydrodynamic and thermally developed turbulent flow through square ducts (3.0 ${\times}$ 3.0 cm) with twisted tape inserts and with twisted tape inserts plus interrupted ribs are conducted to investigate regionally averaged heat transfer and friction factors. Turbulent swirl flows having Reynolds numbers ranging from 8,900 to 29,000, a rib height-to-channel hydraulic diameter(e/D$_h$) of 0.067, and a length-to-hydraulic diameter(L/D$_h$) of 30, are considered. The square ribs are arranged to follow the trace of the twisted tape and along the flow direction defined as axial interrupted ribs. The twisted tape has 0.1 mm thick carbon steel sheet with diameter of 2.8 cm, length of 90 cm, and 2.5 turns. Each wall is composed of isolated aluminum sections, and two cases of surface heating are set. The results show that uneven surface heating enhances the heat transfer coefficient over uniform heating conditions, and square ducts with twisted tape inserts plus interrupted ribs produces the best overall transfer performance.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.11
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• pp.1555-1559
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• 2001

In the first study of a series of experiment samples were taken from 11-13th rib of Hungarian Simmental (HS, n=22) and Holstein-Friesian (HF, n=18) cull cows. In the second one, that of females (n=15) and males (n=12) of HF breed was analysed for amino acid composition, and biological value (BV) of proteins. No significant influence of either breed or slaughter weight was established in this study. Thus, the essential amino acid content and biological value of the proteins in Hungarian Simmental breed are practically the same as in the Holstein-Friesian. On the other hand, gender proved to be a significant factor influencing the amino acid profile of beef proteins, as the quantity of essential amino acids turned out to be significantly larger in females than in males. No statistical difference could be established for the non-essential amino acids and BV between the two genders.