• 대한공업교육학회지
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• v.35 no.2
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• pp.224-237
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• 2010

When the underwater structure sails high speed, noise and vibration propagate to the sensor in the nose of the dome. In this paper, to avoid this kind of noise and vibration CRP(Carbon Reinforced Plastic) material and SNORE ring(Self-NOise REduction Ring) are attached at the curved structure and simulates its isolation characteristics using commercial software. Vibration displacement and stress are calculated at the planar sensor array. The material of the curved structure is aluminum and maximum outer diameter is 53Omm, 215mm in length, 270mm in planar diameter, respectively. Based on the simulation results, reduction ratio of the received normal stress at the sensor is above 95% at the frequency of 12kHz and 15kHz. At the mid point of the planar sensor the normal stress is higher than 20mm and 40mm apart. This results can be used to increase the sensitivity of the acoustic sensor as a basic data.

• Fashion & Textile Research Journal
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• v.18 no.3
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• pp.380-386
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• 2016

This study examined the stainability and functionality of cotton dyed with the extract of Salvia Plebia R. Br. as a research preceding the development of health functional materials and fashion products with a healing motif. The CIELAB measurements of the cotton fabric dyed with the extract of Salvia Plebia R. Br. showed 73.32 for $L^*$, 1.7 for $a^*$, and 37.78 for $b^*$, while the Munsell measurements exhibited 2.63Y in color, 7.18 of brightness, and 5.49 of chroma. The degree of staining resulting from color fastness to laundering, and that resulting from color fastness to perspiration (acid and alkaline), as well as the level of color fastness to crocking (wet and dry) all stayed between relatively higher levels of 4 and 5. The fabric dyed also exhibited SPF 50+, an outstanding sun blocking performance. The deodorization rate was also excellent, rising from 97% to over 99% when the time elapsed increased from 30 minutes to 120 minutes. The fabric dyed also showed a 99.6% antimicrobial activity against staphylococcus aureus ATCC 6538, and a 71.4% antimicrobial activity against Klebsiella pneumoniae ATCC 4352. The aforementioned findings indicate that fabrics dyed with the extract of Salvia Plebia R. Br. contain the potential to be developed for use as health-related materials and fashion products that promote healing.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.22 no.9
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• pp.912-918
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• 2011

In this paper, a composite right-/left-handed(CRLH) rectangular waveguide satisfying a balanced condition above the cut-off frequency is presented. The proposed structure consists of one shorted stub and two twisted H-plane irises which produce an effectively negative permeability and permittivity, respectively. The CRLH structure can independently control the series and shunt resonance frequencies of a CRLH transmission line which determine the left-handed(LH) and right-handed(RH) bands due to a minimized coupling between a shorted stub and twisted H-plane irises. Thus, the design of the CRLH waveguide satisfying a balanced condition is possible. To analyze the CRLH structure, a crossly connected equivalent circuit is derived. The simulated and measured results confirm that the proposed CRLH waveguide has a transmission property without a band gap among the LH and RH bands.

• Journal of the Korean Chemical Society
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• v.54 no.4
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• pp.460-464
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• 2010

We manufactured functional contact lens materials using 2-hydroxy-4-methoxy-benzophenone, titanium(VI) isopropoxide and nanogold, nanoplatinum with UV-blocking and antimicrobial effects. Contact lens was manufactured by cast mould method. The resulting mixture was copolymerized by heating at $70^{\circ}C$ for about 40 min, at $80^{\circ}C$ for about 40 min, and finally at $100^{\circ}C$ for about 40 min. The refractive index of 1.434 ~ 1.436, water content of 35.24 ~ 36.32%, and visible transmittance of 88.3 ~ 90.8% were obtained for the contact lens materials. The polymer materials satisfied the physical properties required to make the material suitable to be applied as a functional material for ophthalmological purposes.

• Korean Chemical Engineering Research
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• v.60 no.4
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• pp.557-563
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• 2022

In order to measure the allergen penetration of micropore fabrics, it is necessary to develop a convenient and appropriate experimental method for measuring a pore size of micropore fabrics. In this study, a simple and economical experimental apparatus was developed for the analysis of the pore size of micropore fabrics by measuring the weight reduction rate. In addition, the allergen blocking properties was evaluated by measuring the pore sizes of various fabrics. According to this study, the size of the pores of the microporous fabric could be obtained by measuring the weight reduction rates. In addition, higher weight reduction rate was obtained as the suction pressure passing through the particle permeation device decreased and the suction time was increased. It is expected that the developed experimental method and apparatus can be utilized as an experimental standard for quality control methods to verify the effectiveness of micropore fabrics used for house dust mite blocking bedding.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.4
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• pp.618-623
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• 2008

In an attempt to find natural sources of antioxidants and whitening agents, comparisons of the antioxidative and tyrosinase inhibitory activities of various ethanol extracts of Eucommiae Cortex, Salviae miltiorrhizae radix, Aurantii nobilis pericarpium and Cnidii rhizoma were carried out. Comparison of the four ethanol extracts revealed that, Aurantii nobilis pericarpium had the highest electron-donating ability(79.0%),; however, Salviae miltiorrhizae radix had the highest SOD-like ability(21.9%). The xanthine oxidase experiment exhibited a hindrance effect of 79.3% in Salviae miltiorrhizae radix, 57.5% in Eucommiae cortex and 71.9% in Aurantii nobilis pericarpium. A tyrosinase inhibitory activity assay was conducted to evaluate the whitening effects of the extracts, The tyrosinase inhibitory activity was 12.4% in the Eucommiae cortex, 22.8% in the Salviae miltiorrhizae radix, 27.5% in the Aurantii nobilis pericarpium and 59.5% in the Cnidii rhizoma. Based on these results, we suggest that the ethanol extracts of Eucommiae cortex, Salviae miltiorrhizae radix, Aurantii nobilis pericarpium and Cnidii rhizoma. can be used as food and cosmetic ingredients.

• The Journal of Korean Orthopaedic Ultrasound Society
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• v.7 no.1
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• pp.28-32
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• 2014

Purpose: We aim to determine sciatic nerve bifurcation location and depth at the level of the popliteal fossa in Korean female. Materials and Methods: Thirty three subjects were enrolled in Korean female. M-turbo ultrasound system (SonoSite, bothell, WA, USA)with 38 mm high frequency linear array transducer, 13-6 MHz probe was used for ultrasound measurements. With subject lying prone, the location of the sciatic nerve in relation to the popliteal crease and skin to nerve distance were assessed via ultrasound. Analyses were performed with SAS version 9.3 using multiple linear regression. Results: Thirty three subjects were enrolled. Distance from the popliteal crease to the sciatic nerve was 4.5-7.5 (mean 5.7 cm), and the depth of the sciatic nerve from the skin was 1.8-3.2 (mean 2.4 cm). Multiple linear regression for the usefulness of the model has a p value of 0.036, shows between weight and depth. Conclusion: We show that variability exists for sciatic nerve bifurcation location in Korean female, The success rate is creased if consider the relations between weight and depth when performs sciatic nerve block in Korean female. In our study, a sciatic nerve block is recommend that performed 7.5 cm proximal to the crease in the popliteal fossa.

• Journal of Digital Convergence
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• v.17 no.11
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• pp.207-213
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• 2019

The fuel-cut coast-down driving mode is activated when the acceleration pedal is released with transmission gear engaged, and it's a default function for electronic-controlled engine of vehicles. The fuel economy becomes better because fuel injection stops during fuel-cut driving mode. A fuel-cut detection method is suggested in the study and it's based on the speed, acceleration and road gradient data from GPS sensor. It detects fuel-cut driving mode by comparing calculated acceleration and realtime acceleration value. The one is estimated with driving resistance in the condition of fuel-cut driving and the other is from GPS sensor. The detection accuracy is about 80% when the method is verified with road driving data. The result is estimated with 9,600 data set of vehicle speed, acceleration, fuel consumption and road gradient from test driving on the road of 12km during 16 minutes, and the road slope is rather high. It's easy to detect fuel-cut without injector signal obtained by connecting wire. The detection error is from the fact that the variation range of speed, acceleration and road gradient data, used for road resistance force, is larger than the value of fuel consumption data.

• Journal of Korean Society of Forest Science
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• v.100 no.3
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• pp.483-493
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• 2011

Erosion control dams play a primary role in preventing or controlling natural disasters (landslide and debris flow etc.) and also conserve ecosystem in forested watersheds. This study examines structural characteristics of the dams such as the height of ecosystem control and the ecosystem permeability of the erosion control dams under standard drawings and the existing construction works. The objective of this study was to characterize the type classification of erosion control dams as ecosystem. Average permeability was highest on eco-piller dam (63.0%), followed in increasing order by wire rope (13.9%), silt dam (10.9%), multifunctional dam (7.2%), and gravity dam (0.4%). The height of ecosystem control was highest on gravity dam (3.2 m), followed in increasing order by multifunctional dam (1.7 m), wire rope dam (1.2 m), silt dam (0.6 m), and eco-piller dam (0.0 m). Criteria for defining the height of ecosystem control was indefinite. We grouped erosion control dams into three functional types (eco-connection, eco-semi connection, and eco-disconnection) by considering physical and structural characteristics such as the ecosystem permeability and the height of ecosystem control. The type of eco-connection (permeability > 20%) had connection areas from streambed to adjacent riparian areas, and these connection areas serve as ecosystem corridors for fauna and flora. Typical wildlife species includes mammals, reptiles, amphibians, and fishes. The type of eco-semi connection (5% < permeability < 20%) had < 2 m in the eco-barrier height from streambed, however, this type of dams partially serve as wildlife corridors and often provide fish ways. The type of eco-disconnection (permeability < 5%) had > 2 m in the eco-barrier height from streambed, thereby preventing wildlife movement.

• Asian Journal of Turfgrass Science
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• v.23 no.1
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• pp.35-44
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• 2009

This study was carried out to examine the growth performance of 4 species of cool-season grasses and 4 species of zoysiagrasses under salt injury in Seo-san reclaimed area. Grasses were grown on the plots with capillary water interruption layer (WCWIL) and without capillary water interruption layer (WOCWIL) soil systems. Cool-season grass and seeding-type zoysiagrass plots were seeded on 6 Jun, 2006. Vegetative zoysiagrass 'Junggi' was established by sprigging and 'Senock' and 'Millock' were plugged. Electric conductivities of irrigation water (ECw) ranged from 0.28 to $3.3\;dS{\cdot}m^{-1}$. Electric conductivities (ECe) of the soil with capillary water interruption layer and without capillary water interruption layer ranged from 0.55 to $9.4\;dS{\cdot}m^{-1}$ and from 1.84 to $9.4\;dS{\cdot}m^{-1}$ respectively. Leaf color, turf quality, coverage rates, and growth rates were rated visually for 2 years. Zoysiagrass 'Junggi', creeping bentgrass, zoysiagrass 'Senock' and 'Millock' showed acceptable growth at salty fairway condition, while Kentucky bluegrass, perennial ryegrass, Kentucky bluegrass mixed with perennial ryegrass, and seeded zoysiagrass 'Zenith' showed establishment rates below 70%. These results will be useful when choosing turf grass species and cultivars for the golf courses in reclaimed land area.