• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.14 no.11
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• pp.1113-1120
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• 2003

It is expected in the future that the demand of optical subcarrier multiplexing system, in which a number of small size base stations with only antenna and RF transmission are connected to central station using optical fiber, will be increased in the CDMA digital cellular mobile communication network. In this paper, in order to analysis the performance of optical SCM system fur CDMA RF signal transmission, MZ modulator is modelled as a non-linear transfer function with cubic operation. The performance degradation due to multipath signals and other user signals through MB modulator is analyzed and the performance is improved using the Rake receiver.

• Aerospace Engineering and Technology
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• v.1 no.2
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• pp.1-10
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• 2002

Flow computations around forward sweep wing small aircraft have been conducted in this study. The main-wing of the forward-wing small aircraft is composed of two planforms: the inboard wing section with backward sweep angle which is known as strake and the outboard wing section with forward sweep angle. The geometrical discontinuity or kink generated by the combination of these two different planforms requires detailed flow analysis around wing. Four different solvers were used to calculate aerodynamic data and the accuracy of each method is examined. For the convenience of grid generation over the aircraft geometry, the overset grid method was applied. Through this calculation, the basic aerodynamic data of the forward-wing aircraft were provided and the aerodynamic characteristics of the wing is expounded.

• Plant Journal
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• v.12 no.3
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• pp.32-38
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• 2016

In this study, the effect of wake on the energy production of a downstream wind turbine was analyzed on the base of operation practices of wind farm in the coastal complex terrain which has 2 row array of wind turbines. And changes in the variation of wind speed and turbulence intensity was analyzed. In case wind turbines are spaced 4-rotor diameter-apart in the prevailing wind direction, reduction in energy production was confirmed due to the decrease of wind speed and the increase of turbulence intensity by wake. Especially a radical change of wind direction caused wind turbine a sudden stop and energy production significantly reduced. It is considered improvement of yaw brake can prevent the sudden stop and increase energy production.

• Journal of Animal Science and Technology
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• v.47 no.6
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• pp.1001-1008
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• 2005

This study examined the effect of corn processing with varying rumen undegradable protein (RUP) on feed intake, milk yield, its composition and, blood characteristics in Holstein cows during the transitional period (21 days pre partum to 21 days post partum). Twenty Holstein cows were randomly assigned to four diets (five cows/diet), ground corn with 30 % RUP (GCR30), ground corn with 40 % RUP (GCR40), flaked corn with 30 % RUP (FCR30), and flaked corn with 40 % RUP (FCR40). The processed corn with varying RUP was fed in total mixed rations (TMR) to cows. Dry matter intake (DMI) was higher with 40 % RUP diet than with 30 % RUP diet, resulting in higher protein and energy intake by cows during pre and post partum (p＜0.05). However, it was not affected by corn processing during pre and post partum. Similarly milk yield was higher with 40 % RUP diet than with 30 % RUP diet. and milk yield was affected by corn processing at RUP 30 % level. Corn processing did not affected the milk fat and protein contents in dairy cows. The concentration of blood non esterified fatty acid (NEFA) were effected by RUP level with flaked corn, however, it was non-significant with RUP levels when given with ground corn. It is concluded that increasing RUP from 30 % to 40 % in iso-nitrogenous diet could increase milk yield in dairy cows during the transitional phase.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.45 no.3
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• pp.217-225
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• 2017

This research represents comparison and validation of static aerodynamic results in different wind tunnel organizations and EFD-CFD results. KAFA conducted wind tunnel tests with Standard Dynamics Model(SDM) which is based on the NRC model, the same configuration of KARI; and then compared and analyzed similarities and differences of the data from KARI and NRC results for verifying the accuracy of wind tunnel tests. Also, We compared the result of CFD with that of wind tunnel tests and examined strakes effect in static characteristics which are attached on the forward fuselage of SDM for investigating the cause of some discrepancies. From this analysis, there are some discrepancies in Cm tendency between EFD-CFD and it did not show the big difference of aerodynamic characteristics by strake effects. Thus, we need to research additionally for analyzing the different cause of some discrepancies such as vortex structures by the rear strut or intake of SDM and regenerating grid resolution of CFD.

• Journal of the Korean GEO-environmental Society
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• v.16 no.12
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• pp.53-58
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• 2015

Engineers should take great care of characterizing the engineering properties of mudrock, because the uncemented mudrock can be considered as a hard rock in appearance. Therefore, the mudrock samples obtained from the cut slope in Gyeongki-do were tested to evaluate the strength characteristics of uncemented mudrock in this study. The performed tests are index properties, slake durability, and swelling tests for the classification of the mudrock for engineering practice. To evaluate the effect of water on the engineering properties of the uncemented mudrock, resonant column, triaxial compression and direct shear tests with various water contents were performed. With the increasing water contents, stiffness at very small to small strain region and the cohesion value of the strength parameters decrease. Based on the test results, engineers should take great care of evaluating the engineering properties of uncemented mudrock.

• Korean Journal of Food Science and Technology
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• v.36 no.2
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• pp.276-282
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• 2004

Barley flakes were developed by extrusion cooking using broken kernels, by-products of the barley pearling process. Broken kernels from both non-waxy and waxy barley broken kernels were sufficiently gelatinized at the barrel temperature of over $100^{\circ}C$ and the moisture content of broken kernels of over 35%. Cutting and flaking roll separating properties of pellets prepared from non-waxy barley broken kernels were better than those of waxy barley broken kernels. Characteristics of pellets prepared by extrusion cooking in different mixing ratios of non-waxy and waxy barley broken kernels were investigated. As the mixing ratio of waxy barley broken kernels increased, RVA peak viscosity, apparent viscosity, and yield stress of prepared pellets decreased, while flow behavior index increased. As the mixing ratio of waxy barley broken kernels increased, compressive strength and bulk density of deep-fat fried flakes drastically decreased, and the size of air cells on cross-section increased, and thickness of cell-constituting bodies decreased. Sensory evaluation results showed that acceptability for texture and taste of flakes inclosed as the mixing ratio of waxy barley broken kernels increased, and optimum mixing level of waxy barley broken kernels appeared to be 30-40%.

• Economic and Environmental Geology
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• v.35 no.3
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• pp.273-284
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• 2002

The Gravity-Geologic Method (GGM) was implemented for bathymetric determinations in the Drake Passage, Antarctica, using global marine Free-air Gravity Anomalies (FAGA) data sets by Sandwell and Smith (1997) and local echo sounding measurements. Of the 6548 bathymetric sounding measurements, two thirds of these points were used as control depths, while the remaining values were used as checkpoints. A density contrast of 9.0 gm/㎤ was selected based on the checkpoints predictions with changes in the density contrast assumed between the seawater and ocean bottom topographic mass. Control depths from the echo soundings were used to determine regional gravity components that were removed from FAGA to estimate the gravity effects of the bathymetry. These gravity effects were converted to bathymetry by inversion. In particular, a selective merging technique was developed to effectively combine the echo sounding depths with the GGM bathymetiy to enhance high frequency components along the shipborne sounding tracklines. For the rugged bathymetry of the research area, the GGM bathymetry shows correlation coefficients (CC) of 0.91, 0.92, and 0.85 with local shipborne sounding by KORDI, GEODAS, and a global ETOPO5 model, respectively. The enhanced GGM by selective merging shows imploved CCs of 0.948 and 0.954 with GEODAS and Smith & Sandwell (1997)'s predictions with RMS differences of 449.8 and 441.3 meters. The global marine FAGA data sets and other bathymetric models ensure that the GGM can be used in conjunction with shipborne bathymetry from echo sounding to extend the coverage into the unmapped regions, which should generate better results than simply gridding the sparse data or relying upon lower resolution global data sets such as ETOPO5.

• Food Engineering Progress
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• v.14 no.2
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• pp.99-105
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• 2010

Proximate composition of whole hemp seed, paste viscosity of whole hemp seed pellets, bulk density, color, compression force, water solubility and absorption index and bowl life of whole hemp seed flakes manufactured by extrusion process were determined to evaluate whole hemp seed as flake additive. Extrusion process conditions were 35% of moisture content and 90, 100 and 110$^{\circ}C$ of barrel temperature. Content of moisture content, crude protein, crude fat, crude ash from whole hemp seed were 5.67${\pm}$0.02%, 25.93${\pm}$0.16%, 28.21${\pm}$0.56% and 7.70${\pm}$0.08%, respectively. The pellets hemp seed at 100 or 110$^{\circ}C$ had higher paste viscosity as compared to those pellet at 90$^{\circ}C$. The bulk density values of all hemp seed flakes were between 0.24 to 0.43 g/mL, depending on the barrel temperatures. The hardness of flake increased with decreasing percentage of hemp seed in flakes. An increase in barrel temperature from 90$^{\circ}C$ to 110$^{\circ}C$ resulted in increase of WSI and decrease of WAI. The bowl life of hemp seed flakes was increased from 5.8 to 15.5 min with the decrease in percentage of hemp seed. The highest overall quality was showed in flake added with 20% of hemp seed.

• Proceedings of the Costume Culture Conference
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• 2003.09a
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• pp.39-40
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• 2003

메이크업(Make up)은 일상생활에서 여성들의 전체 ‘룩(Look)’을 구성하는데 없어서는 안될 중요한 요소이다. 여성들은 상황에 맞게 자신들의 의상을 선택하고 머리손질을 하며 화장을 한다. 제니퍼 크레이크(2001)는 ‘화장은 인격과 지위라는 속성뿐 아니라 성적 속성을 구성한다’고 밝히면서 메이크업을 여성성 표현을 위한 바디테크닉의 하나로 간주했다. 즉, 여성들은 메이크업을 통해 여성들만이 가지는 특유의 미를 발산함으로써 자기만족과 이성에 대한 관심을 유도한다. (중략)