• Journal of Advanced Navigation Technology
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• v.22 no.5
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• pp.449-455
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• 2018

For the size reduction, we propose a microstrip-fed monopole antenna with half X-slot in the radiation patch and cover WLAN dual band 2.4 GHz band (2.4 ~ 2.484 GHz) and 5 GHz band (5.15 ~ 5.825 GHz). The frequency characteristics such as impedance bandwidth and resonant frequencies were satisfied by optimizing the numerical values of various parameters, while the reflection loss in 5 GHz was improved by using defected ground structure (DGS). The proposed antenna is designed and fabricated on a FR-4 substrate with dielectric constant 4.3, thickness of 1.6 mm, and size of $24{\times}41mm^2$. The measured impedance bandwidths (${\mid}S_{11}{\mid}{\leq}-10dB$) of fabricated antenna are 450 MHz (2.27 ~ 2.72 GHz) in 2.4 GHz band and 1340 MHz (4.79 ~ 6.13 GHz) in 5 GHz band which sufficiently satisfied with the IEEE 802. 11n standard in dual band. In particular, radiation patterns which are stable as well as relatively omni-direction could be obtained, and the gain of antennas in each band was 1.31 and 1.98 dBi respectively.

• Journal of Biomedical Engineering Research
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• v.26 no.6
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• pp.393-398
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• 2005

An electromechanical type is the most useful mechanism in the various pumping mechanisms. It, however, requires a movement converting system including a ball screw, a helical cam, or a solenoid-beam spring, which makes the device complex and may lessen reliability. Thus, the authors have hypothesized that an electromagnetic actuator mechanism can eliminate the movement converting system and that thereby enhance the mechanical reliability and operative simplicity of an electro­pneumatic pump. The purpose of this study was to show a novel application of electromagnetic actuator mechanism in pulsatile pump and to provide preliminary data for further evaluations. The electromagnetic actuator consists of stators with a single winding excitation coil and movers with a high energy density neodymium-iron-boron permanent magnet. A 0.5mm diameter wire was used for the excitation coil, and 1000 turns were wound onto the stators core with parallel. A prototype of extracorporeal electro-pneumatic pump was constructed, and the pump performance tests were performed using a mock system to evaluate the efficiency of the electromagnetic actuator mechanism. When forward and backward electric currents were supplied to the excitation coil, the mover effectively moved back and forth. The nominal stroke length of the actuator was 10mm. The actuator dimension was 120mm in diameter and 65mm in height with a mass of 1.4kg. The prototype pump unit was 150mm in diameter, 150mm in thickness and 4.5kg in weight. The maximum force output was 70N at input current of 4.5A and the maximum pump rate was 150 beats per minute. The maximum output was 2.0 L/minute at a rate of 80bpm when the afterload was 100mmHg. The electromagnetic actuator mechanism was successfully applied to construct the prototype of extracorporeal electro­pneumatic pump. The authors provide the above results as a preliminary data for further studies.

• Journal of The Korean Society of Grassland and Forage Science
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• v.31 no.1
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• pp.9-14
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• 2011

This experiment was carried out to breed a very early maturing variety of Italian ryegrass (Lolium multiflorum Lam.) in Grassland and Forage Crops Division, National Institute of Animal Science, RDA, Cheonan from 2009 to 2010. A new variety, 'Green farm' is a diploid variety with green in leaf color and has erect and semi-erect growth habit in late autumn and early spring, respectively. 'Green farm' was on 28 April in heading date as a early-maturing variety. 'Green farm' was also wider by 0.4 mm in flag leaf width, longer by 0.8 cm in flag leaf length and shorter by 5 cm in plant height than those of control variety, 'Florida 80', respectively. 'Green farm' was thicker in stem thickness and stronger in winter hardness than those of the 'Florida 80'. Dry matter (DM) yield (11,790 kg/ha) of 'Green farm' was similar to that of 'Florida 80'. In vitro dry matter digestibility (IVDMD), total digestible nutrient (TDN) and crude protein (CP) of 'Green farm' were 68.7, 63.3 and 10.3% which are 1.9, 1.7 and 0.6% higher than those of 'Florida 80', respectively. Acid detergent fiber (ADF) and neutral detergent fiber (NDF) of 'Green farm' were 32.5 and 54.6% which are 2.2 and 4.3% lower than those of the 'Florida 80', respectively.

• Journal of The Korean Society of Grassland and Forage Science
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• v.33 no.1
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• pp.10-14
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• 2013

This experiment was carried out to breed an early maturing variety of Italian ryegrass (Lolium multiflorum Lam.) in the Grassland and Forage Crops Division, National Institute of Animal Science, RDA, Cheonan from 2009 to 2011. A new variety, 'Green farm II' is a diploid with green leaves and has a semi-erect growth habit in late autumn and erect growth habit in early spring, respectively. 'Green farm II' was on the $28^{th}$ of April in the heading date as an early-maturing variety. 'Green farm II' was also wider by 0.6 mm in flag leaf width, shorter by 1 cm in flag leaf length and shorter by 1 cm in plant length than those of the control variety, 'Florida 80', respectively. 'Green farm II' was thicker by 0.7 mm in stem thickness and strong in winter hardness. Dry matter (DM) yield (11,452 kg/ha) of 'Green farm II' was similar to that of 'Florida 80'. In vitro dry matter digestibility (IVDMD), total digestible nutrients (TDN), and relative feed value (RFV) of 'Green farm II' were 70.6%, 63.9%, and 114% higher than those of 'Florida 80', respectively. Acid detergent fiber (ADF) and neutral detergent fiber (NDF) of 'Green farm II' were 31.7% and 52.6% which were 3.5% and 6.4% lower than those of 'Florida 80', respectively.

• Archives of Reconstructive Microsurgery
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• v.3 no.1
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• pp.45-53
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• 1994

Suture microvascular anastomosis is time-consuming and tedious and demands long and continuous training. Techinique of anastomosis of microvessel was presented interrupted suture and continuous suture. Recently the unilink instrument system is created as a fast and simple method to achieve high patency rates without long and continuous training in the anastomosis of small vessels. The author experimentally studied the femoral artery of 20 mice(0.5-1.0mm, av. 0.7mm), the femoral vein of 20 mice(0.8-1.6mm, av. 1.2mm) after anastomosis with interrupted suture in 20 cases and continuous sutre in 20 cases. For the unilink apparatus we used the carotid arteries of 15 cases in 14 rabbits(1.0-1.6mm, av. 1.3mm) and facial veins of 12 cases in 14 rabbits(0.9mm-2.2mm, av. 1.5mm). A total of 27 arterial and venous anastomoses were performed. We examined the postoperative patency at immediate, 2 weeks, and 8 weeks. The results were as followings, 1. In the arterial anastomosis the rate of patency was 90%(18/20) in interrupted suture, 90%(18/20) in continuous suture and 93%(13/15) in unilink apparatus. In the venous anastomosis the rate of patency was 90%(18/20) in interrupted suture, 80%(16/20) in continuous suture and 100%(9/9) in unilink apparatus. 2. The mean time for completion of the arterial anastomosis were 12.2 minutes in interrupted suture group, 10.3 minutes in continouous suture group and 8.5 minutes in unillnk apparatus group. The mean time for completion of the venous anastomosis were 13.6 minutes in interrupted suture group, 11.0 minutes in continuous suture group and 6.2 minutes in unilink apparatus group. 3. At the histological examination of suture group, hyperplastic reaction of middle layer and subintimal hyperplasia were observed. In unilink apparatus group, the endothelium layer was continued and the thickness of vessel wall was decreased due to moderate atrophy of the media and mild degree of nonspecific chronic inflammation were seen around the unilink apparatus. 4. No significants was noticied in foreign body reaction among the interrupted, continuous and unilink apparatus group. 5. A case of the arterial anastomosis was released with acting out at 15 minutes after operation. 6. The important factors in the technical problems were accurate apposition of the cut vessel edges in suture group and the proper selection of the ring size and optimal fitting between two rings in unilink apparatus group. Even though the outer diamater of vessel in suture group was different from that in unilink apparatus group the unilink method provides a very safe, fast, and simple way to perform microvascular anastomoses especially in anastomosis of vein. But howerver suture was needed in vessels below 1 mm outer diamater. In that situation continuous suture was benefit than the interrupted suture in operation time.

• Economic and Environmental Geology
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• v.37 no.2
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• pp.207-223
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• 2004

The purpose of this study is to reveal spatial relationships between landslide and geospatial data set, to map the landslide susceptibility using the relationship and to verify the landslide susceptibility using the landslide occurrence data in Boun area in 1998. Landslide locations were detected from aerial photography and field survey, and then topography, soil, forest, and land cover data set were constructed as a spatial database using GIS. Various spatial parameters were used as the landslide occurrence factors. They are slope, aspect, curvature and type of topography, texture, material, drainage and effective thickness of soil. type, age, diameter and density of wood, lithology, distance from lineament and land cover. To calculate the relationship between landslides and geospatial database, Bayesian probability methods, weight of evidence. were applied and the contrast value that is >$W^{+}$->$W^{-}$ were calculated. The landslide susceptibility index was calculated by summation of the contrast value and the landslide susceptibility maps were generated using the index. The landslide susceptibility map can be used to reduce associated hazards, and to plan land cover and construction.

• Korean Journal of Environmental Agriculture
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• v.22 no.2
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• pp.124-129
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• 2003

The objectives of this study are to manufacture an efficient $TiO_2$, photocatalyst and to delineate optimum operational parameters for TCE (trichloroethylene) degradation in a photocatalytic oxidative reactor. The $TiO_2$ photocatalyst irradiated by 365 nm UV light is expected to increase degradation of TCE in solution by a series of photocatalytic oxidations in the reactor. A new membrane $TiO_2$ photocatalyst wns eventually developed by coating a mixture of Davan-C(0.24 wt%) and PVA(0.16 wt%) on the surface of slips using the slip-casting method. Results show that increase in the number of coating of $TiO_2$ sol on surface of photocatalysts and in the surface thickness improved the endurance and photocatalysts, but these physical modifications caused significant decrease in the overall degradation efficiency of TCE. Pre-aeration or recirculation of the influents to the reactors containing TCE increased degradation efficiency of TCE. The optimum operational conditions far the surface area of photocatalysts and UV light intensity appeared to be $1.47\;mL/cm^2$ and $225\;W/cm^2{\times}100$, respectively, in the reactor. Based on the overall experimental results, the photocatalytic oxidation of TCE with the new membrane $TiO_2$ photocatalyst is found to be very effective under the operational conditions delineated in this study.

• Journal of The Korean Society of Grassland and Forage Science
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• v.29 no.4
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• pp.375-382
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• 2009

This study examined the influence of forage source (grass hay and rice straw) and shipping time (24, 26, 28 and 30 months) on feed conversion ratio, growth performance and carcass characteristics of Hanwoo steers. Sixty four Hanwoo steers at 6 months age were fed either grass hay (n=32) or rice straw (n=32) for 24, 26, 28 and 30 months of age. Steers fed on mixed grass hay gained significantly higher body weight at 24, 26, 28 and 30 months compared with those fed on rice straw. Feed efficiency was slightly better in steers fed mixed grass hay compared to those fed rice straw. Back fat thickness and marbling score were increased with the age of steers (p<0.05). Carcass quality traits (meat color, fat color, texture and maturity) were not affected by forage source and shipping time. Shear force, cooking loss and water holding capacity of beef were reduced with advancing age of steers (p<0.05). Moisture content was lower and fat content was higher in beef produced from steers fed mixed grass hay than those fed rice straw (p<0.05). Beef juiciness was reduced with the advancing shipping time of steers. In conclusion, it would be beneficial to feed hay compared with rice straw during whole period of Hanwoo steer to produce high quality beef.

• Korean Journal of Materials Research
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• v.23 no.3
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• pp.155-160
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• 2013

ZnO thin films co-doped with Mg and Ga (MxGyZzO, x + y + z = 1, x = 0.05, y = 0.02 and z = 0.93) were prepared on glass substrates by RF magnetron sputtering with different sputtering powers ranging from 100W to 200W at a substrate temperature of $350^{\circ}C$. The effects of the sputtering power on the structural, morphological, electrical, and optical properties of MGZO thin films were investigated. The X-ray diffraction patterns showed that all the MGZO thin films were grown as a hexagonal wurtzite phase with the preferred orientation on the c-axis without secondary phases such as MgO, $Ga_2O_3$, or $ZnGa_2O_4$. The intensity of the diffraction peak from the (0002) plane of the MGZO thin films was enhanced as the sputtering power increased. The (0002) peak positions of the MGZO thin films was shifted toward, a high diffraction angle as the sputtering power increased. Cross-sectional field emission scanning electron microscopy images of the MGZO thin films showed that all of these films had a columnar structure and their thickness increased with an increase in the sputtering power. MGZO thin film deposited at the sputtering power of 200W showed the best electrical characteristics in terms of the carrier concentration ($4.71{\times}10^{20}cm^{-3}$), charge carrier mobility ($10.2cm^2V^{-1}s^{-1}$) and a minimum resistivity ($1.3{\times}10^{-3}{\Omega}cm$). A UV-visible spectroscopy assessment showed that the MGZO thin films had high transmittance of more than 80 % in the visible region and that the absorption edges of MGZO thin films were very sharp and shifted toward the higher wavelength side, from 270 nm to 340 nm, with an increase in the sputtering power. The band-gap energy of MGZO thin films was widened from 3.74 eV to 3.92 eV with the change in the sputtering power.

• Korean Journal of Medicinal Crop Science
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• v.6 no.3
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• pp.176-180
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• 1998

This experiment was conducted to investigate processing method and usage of dried yam, "Sanyak". Jujube showed the higher value in extract, brix and extract content compared with Danggui and Sanyak. Mixing of Sanyak with Jujube and Danggui was proper to raise extract and taste. Brix and extract content was $1.17^{\circ}$ and 1.80% higher, respectively, in 12 hours of extraction than in 8 hours of extraction. The apt mixing ratio was 3 : 4 : 3 (Sanyak : Danggui : Jujube). By adding 70% of glucose and 10% of lactose to 20% of extract, good viscosity and appearance of paste were obtained. 1.5mm of granule thickness was proper in phase of manufacturing, drying and shaping.