• Food Science and Preservation
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• v.23 no.5
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• pp.746-752
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• 2016

This research was carried out to identify aerodynamic property as a function of moisture content for designing equipment such as for post-harvest management. Terminal velocity of two wheat varieties {Backjjung (B) and Jogyeong (J)} with selected sound, damaged kernel and foreign materials (Wheat stick, Wheat husks) were measured with a designed vertical wind column at different moisture contents from about 9 to 30% wet basis. The results showed that terminal velocity of wheat and foreign materials except of Jogyeong's husks (p<0.05) had a significant difference at p<0.001. With increasing moisture content, the aerodynamic property values of the kernels and foreign materials of the two wheat varieties increased linearly. In detail, terminal velocity of sound and damaged kernel increased from 5.46 to 7.13 m/sec (B) and 7.48 to 8.60 m/sec (J), damaged kernel from 5.91 to 7.00 m/sec (B) and 6.48 to 7.75 m/sec (J). For foreign materials the terminal velocity of wheat stick increased from 2.92 to 4.07 m/sec (B) and 3.74 to 5.22 m/sec (J) whereas that of husks from 1.07 to 1.85 m/sec (B) and 2.02 to 2.33 m/sec (J) each. For air separation of wheat and foreign materials, the air flow should be less than 5.22 m/sec due to the range (1.07~5.22 m/sec) of foreign materials in wheat.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.47 no.5
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• pp.50-60
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• 2010

For the last half a century, the personal computer and software industries have been prosperous due to the incessant evolution of computer systems. In the 21st century, the embedded system market has greatly increased as the market shifted to the mobile gadget field. While a lot of multimedia gadgets such as mobile phone, navigation system, PMP, etc. are pouring into the market, most industrial control systems still rely on 8-bit micro-controllers and simple application software techniques. Unfortunately, the technological barrier which requires additional investment and higher quality manpower to overcome, and the business risks which come from the uncertainty of the market growth and the competitiveness of the resulting products have prevented the companies in the industry from taking advantage of such fancy technologies. However, high performance, low-power and low-cost hardware and software platforms will enable their high-technology products to be developed and recognized by potential clients in the future. This paper presents such a platform for industrial embedded systems. The platform was designed based on Telechips TCC8300 multimedia processor which embedded a variety of parallel hardware for the implementation of multimedia functions. And open-source Embedded Linux, TinyX and GTK+ are used for implementation of GUI to minimize technology costs. In order to estimate the expected performance and power consumption, the performance improvement and the power consumption due to each of enabled hardware sub-systems including YUV2RGB frame converter are measured. An analytic model was devised to check the feasibility of a new application and trade off its performance and power consumption. The validity of the model has been confirmed by implementing a real target system. The cost can be further mitigated by using the hardware parts which are being used for mass production products mostly in the cell-phone market.

• Journal of Dental Rehabilitation and Applied Science
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• v.24 no.4
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• pp.389-403
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• 2008

In Angle's Class III malocclusion, which has higher incidence in Korean than Western, depressed midfacial profile with protruded lower lips and mandible may give rise to many functional, esthetic, psychological, social problems. Due to the different malocclusion incidence according to racial differences, many previous studies focused on the relationship between Class II malocclusion and nasal airway obstruction. Previous studies used lateral cephalography which has limitations of 2 dimensional image with projection error and identification error. Therefore, the purpose of this study was to analyze morphologic differences in the nasal airway between normal occlusion and Angle's Class III malocclusion patients using 3-dimensional facial computed tomography. Thirteen normal occlusion(7 men and 6 women) and sixteen skeletal Class III(7 men and 9 women) patients were selected and 3-dimensional facial computed tomography taking was performed. Comparison between two group in volume and sectional area of nasal airway were carried out. The results were followed. 1. In the comparison of absolute nasal airway volume, oropharyngeal space of experimental group were larger than control group but there are no significant difference in other. 2. In the comparison of relative nasal airway volume, oropharyngeal space of experimental group were larger than control group but there are no significant difference in other. 3. In the oropharyngeal space width on frontal and lateral view, the similar tendency was revealed between two groups. 4. In the lateral curvature of nasal airway, the similar tendency was revealed between two groups.

• Journal of the Korean Geophysical Society
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• v.2 no.1
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• pp.9-26
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• 1999

The Ulleung Basin (Tsushima Basin) in the southwestern East Sea (Japan Sea) is floored by a crust whose affinity is not known whether oceanic or thinned continental. This ambiguity resulted in unconstrained mechanisms of basin evolution. The present work attempts to define the nature of the crust of the Ulleung Basin and its tectonic evolution using seismic wide-angle reflection and refraction data recorded on ocean bottom seismometers (OBSs). Although the thickness of (10 km) of the crust is greater than typical oceanic crust, tau-p analysis of OBS data and forward modeling by 2-D ray tracing suggest that it is oceanic in character: (1) the crust consists of laterally consistent upper and lower layers that are typical of oceanic layers 2 and 3 in seismic velocity and gradient distribution and (2) layer 2C, the transition between layer 2 and layer 3 in oceanic crust, is manifested by a continuous velocity increase from 5.7 to 6.3 km/s over the thickness interval of about 1 km between the upper and lower layers. Therefore it is not likely that the Ulleung Basin was formed by the crustal extension of the southwestern Japan Arc where crustal structure is typically continental. Instead, the thickness of the crust and its velocity structure suggest that the Ulleung Basin was formed by seafloor spreading in a region of hotter than normal mantle surrounding a distant mantle plume, not directly above the core of the plume. It seems that the mantle plume was located in northeast China. This suggestion is consistent with geochemical data that indicate the influence of a mantle plume on the production of volcanic rocks in and around the Ulleung Basin. Thus we propose that the opening models of the southwestern East Sea should incorporate seafloor spreading and the influence of a mantle plume rather than the extension of the crust of the Japan Arc.

• Geophysics and Geophysical Exploration
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• v.15 no.1
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• pp.39-46
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• 2012

Recently, stratigraphic reservoirs are getting more attention than structural reservoirs which have mostly developed. However, recognizing stratigraphic thin gas reservoirs in a stacked section is usually difficult because of tuning effects. Moreover, if the reflections from the brine-saturated region of a thin layer have the same polarity with those from the gas-saturated region, we could not easily identify the gas reservoir with conventional data processing technique. In this study, we introduced a way to delineate the gas-saturated region in a thin layer reservoir using a spectral decomposition method. First of all, amplitude spectrum with the variation of the frequency and the incident angle was investigated for the medium which represents property of Class 3, Class 1 or Class 4 AVO response. The results show that the maximum difference in the amplitude spectra between brine and gas-saturated thin layers occurs around the peak frequency independent of the incident angle and the type of AVO responses. In addition, the amplitude spectra of the gas-saturated zone are greater than those of brine-saturated one in Class 3 and Class 4 at the peak frequency while those of phenomenon occur oppositely in Class 1. Based on the results, we applied spectral decomposition method to the stacked section in order to distinguish the gas-saturated zone from the brine-saturated zone in a thin layer reservoir. To verify our new method, we constructed a thin-layer velocity model which contains both gas and brine-saturated zones which have the same reflection polarities. As a result, in the spectral decomposed sections near the peak frequency obtained by Wigner-Ville Distribution (WVD), we could identify the difference between reflections from gas- and brinesaturated region in the thin layer reservoir, which was hardly distinguishable in the stacked section.

• Food Science and Preservation
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• v.22 no.5
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• pp.652-659
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• 2015

The physical properties of wheat kernels were determined as a function of moisture content to optimize the design of equipment for post-harvest management. Several properties, including bulk density, dynamic repose angle, one thousand-kernel weight, specific gravity, length, width, thickness, and area of two wheat cultivars (Baekjjung: B and Jogyeong: J ), were studied in the moisture range from approximately 9% to 30% wet basis. As moisture increased, length increased linearly from 6.42 to 7.20 mm (B) and 8.71 to 9.15 mm (J), width increased from 2.90 to 3.49 mm (B) and 4.12 to 4.43 mm (J), thickness from 2.94 to 3.20 mm (B) and 3.29 to 3.63 mm (J), and area from 14.13 to $19.44mm^2$ (B) and 27.75 to $31.25mm^2$ (J). Additionally, the dynamic repose angle and one thousand-kernel weight increased linearly from $46.3^{\circ}$ to $54.0^{\circ}$ (B) and $46.3^{\circ}$ to $54.5^{\circ}$ (J) and from 32.26 to 41.51 g (B) and 45.30 to 63.07 g (J), respectively, as the moisture content increased. Based on the experimental measurements, only the bulk density and specific gravity decreased from 754.0 to $664.1kgm^{-3}$ (B) and 776.1 to $660.0kgm^{-3}$ (J) and from 1.2950 to 1.2265 (B) and 1.3379 to 1.2671 (J), respectively, as moisture content increased.

• The Journal of Engineering Geology
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• v.14 no.1
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• pp.29-46
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• 2004

It is important to identify geometries of fracture that act as a conduit of fluid flow for characterization of ground water flow in fractured rock. Fracture geometries control hydraulic conductivity and stream lines in a rock mass. However, we have difficulties to acquire whole geometric data of fractures in a field scale because of discontinuous distribution of outcrops and impossibility of continuous collecting of subsurface data. Therefore, it is needed to develop a method to describe whole feature of a target fracture geometry. This study suggests a new approach to develop a method to characterize on the whole feature of a target fracture geometry based on the Fourier transform. After sampling of specimens along a target fracture from borehole cores, effective frequencies among roughness components were selected by the Fourier transform on each specimen. Then, the selected effective frequencies were averaged on each frequency. Because the averaged spectrum includes all the frequency profiles of each specimen, it shows the representative components of the fracture roughness of the target fracture. The inverse Fourier transform is conducted to reconstruct an averaged whole roughness feature after low pass filtering. The reconstructed roughness feature also shows the representative roughness of the target subsurface fracture including the geometrical characteristics of each specimen. It also means that overall roughness feature by scaling up of a fracture. In order to identify the characteristics of permeability coefficients along the target fracture, fracture models were constructed based on the reconstructed roughness feature. The computation of permeability coefficient was performed by the homogenization analysis that can calculate accurate permeability coefficients with full consideration of fracture geometry. The results show a range between $10^{-4}{\;}and{\;}10^{-3}{\;}cm/sec$, indicating reasonable values of permeability coefficient along a large fracture. This approach will be effectively applied to the analysis of permeability characteristics along a large fracture as well as identification of the whole feature of a fracture in a field scale.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.6
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• pp.666-672
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• 1997

Twenty years' daily mean air temperature data was used to calculate the critical early seeding date(CESD), the optimum heading date(OHD), the critical late heading date for stable ripening(CHDR) and the critical late ripening date(CLRD) for rice seeded on dry paddy in different agroclimatic zones in Korea. The CESD was defined as the first day with mean air temperature of 13$^{\circ}C$, and the OHD as the first day of the 40 consecutive days with mean air temperature of 22$^{\circ}C$ or above after heading. The CHDR was defined as the date after which the cumulative daily mean air temperature would be at least 76$0^{\circ}C$. Lastly, the CLRD was defined as the last day when daily mean air temperature remains above 15$^{\circ}C$. This information was used for the estimation of periods from the earliest date of seeding to optimum heading date, the latest possible date of heading and the latest possible date of ripening in respective regions. For instance, in Suwon, those respective periods mentioned were found to be 104days, 124days, and 165days.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.62 no.4
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• pp.333-345
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• 2017

The potato tuber is known as a rich source of essential nutrients, used throughout the world. Although potato-breeding programs share some priorities, the major objective is to increase the genetic potential for yield through breeding or to eliminate hazards that reduce yield. Glycoalkaloids, which are considered a serious hazard to human health, accumulate naturally in potatoes during growth, harvesting, transportation, and storage. Here, we used the AMMI (additive main effects and multiplicative interaction) and GGE (Genotype main effect and genotype by environment interaction) biplot model, to evaluate tuber yield stability and glycoalkaloid content in six potato cultivars across three locations during 2012/2013. The environment on tuber yield had the greatest effect and accounted for 33.0% of the total sum squares; genotypes accounted for 3.8% and $G{\times}E$ interaction accounted for 11.1% which is the nest highest contribution. Conversely, the genotype on glycoalkaloid had the greatest effect and accounted for 82.4% of the total sum squares), whereas environment and $G{\times}E$ effects on this trait accounted for only 0.4% and 3.7%, respectively. Furthermore, potato genotype 'Superior', which covers most of the cultivated area, exhibited high yield performance with stability. 'Goun', which showed lower glycoalkaloid content, was the most suitable and desirable genotype. Results showed that, while tuber yield was more affected by the environment, glycoalkaloid content was more dependent on genotype. Further, the use of the AMMI and GGE biplot model generated more interactive visuals, facilitated the identification of superior genotypes, and suggested decisions on a variety of recommendations for specific environments.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.10
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• pp.916-927
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• 2010

In general water treatment process, the disinfection process by chlorine is used to prevent water borne disease and microbial regrowth in water distribution system. Because chlorines were reacted with organic matter, carcinogens such as disinfection by-products (DBPs) were produced in drinking water. Therefore, a suitable injection of chlorine is need to decrease DBPs. Rechlorination in water pipelines or reservoirs are recently increased to secure the residual chlorine in the end of water pipelines. EPANET 2.0 developed by the U.S. Environmental Protection Agency (EPA) is used to compute the optimal chlorine injection in water treatment plant and to predict the dosage of rechlorination into water distribution system. The bulk decay constant ($k_{bulk}$) was drawn by bottle test and the wall decay constant ($k_{wall}$) was derived from using systermatic analysis method for water quality modeling in target region. In order to predict water quality based on hydraulic analysis model, residual chlorine concentration was forecasted in water distribution system. The formation of DBPs such as trihalomethanes (THMs) was verified with chlorine dosage in lab-scale test. The bulk decay constant ($k_{bulk}$) was rapidly decreased with increasing temperature in the early time. In the case of 25 degrees celsius, the bulk decay constant ($k_{bulk}$) decreased over half after 25 hours later. In this study, there were able to calculate about optimal rechlorine dosage and select on profitable sites in the network map.