• Korean Journal of Radiology
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• v.24 no.4
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• pp.294-304
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• 2023

Objective: We aimed to investigate whether image standardization using deep learning-based computed tomography (CT) image conversion would improve the performance of deep learning-based automated hepatic segmentation across various reconstruction methods. Materials and Methods: We collected contrast-enhanced dual-energy CT of the abdomen that was obtained using various reconstruction methods, including filtered back projection, iterative reconstruction, optimum contrast, and monoenergetic images with 40, 60, and 80 keV. A deep learning based image conversion algorithm was developed to standardize the CT images using 142 CT examinations (128 for training and 14 for tuning). A separate set of 43 CT examinations from 42 patients (mean age, 10.1 years) was used as the test data. A commercial software program (MEDIP PRO v2.0.0.0, MEDICALIP Co. Ltd.) based on 2D U-NET was used to create liver segmentation masks with liver volume. The original 80 keV images were used as the ground truth. We used the paired t-test to compare the segmentation performance in the Dice similarity coefficient (DSC) and difference ratio of the liver volume relative to the ground truth volume before and after image standardization. The concordance correlation coefficient (CCC) was used to assess the agreement between the segmented liver volume and ground-truth volume. Results: The original CT images showed variable and poor segmentation performances. The standardized images achieved significantly higher DSCs for liver segmentation than the original images (DSC [original, 5.40%-91.27%] vs. [standardized, 93.16%-96.74%], all P < 0.001). The difference ratio of liver volume also decreased significantly after image conversion (original, 9.84%-91.37% vs. standardized, 1.99%-4.41%). In all protocols, CCCs improved after image conversion (original, -0.006-0.964 vs. standardized, 0.990-0.998). Conclusion: Deep learning-based CT image standardization can improve the performance of automated hepatic segmentation using CT images reconstructed using various methods. Deep learning-based CT image conversion may have the potential to improve the generalizability of the segmentation network.

• Agricultural and Biosystems Engineering
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• v.3 no.1
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• pp.29-34
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• 2002

Two charging methods of electrostatic nozzle, i.e. induction and ionized field corona charging, were designed and evaluated for orchard sprayer application. An artificial (metallic) target was constructed and used in this experiment. The charge-to-mass ratio for the induction electrode was measured by using the Faraday cage. Two conventional pressure-swirl nozzles have been employed with different orifice diameters under the same experimental operating conditions. A commercial pressure-swirl nozzle with orifice diameter of 1.0 was used for the conventional spray. The diameter of the electrostatic was 0.59 mm. The experiment was carried out for individual nozzle sprays at $0^{\circ}$, $20^{\circ}$ and $50^{\circ}$ oriented angles and three nozzles, sprayed simultaneously at a distance of 1.0 and 2.0 m from the nozzle tip to the target. The nozzles were mounted on a carriage with constant speed of 1.26 km/h with a blower attached. The weighing method was employed to evaluate for the spray deposition, ground loss and estimated drift. The results show more promising for the induction charging method, especially at $20^{\circ}$oriented angle at a distance of 1.0 m from the target for a single nozzle and when all three nozzles were operated simultaneously for spray deposition. The results of the induction charging method show promising with the developed electrostatic technique.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.11 no.6
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• pp.143-152
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• 2008

A comparative analysis of rooftop greening in Korea and Japan was carried out to understand current status of rooftop greening creation and technology and to give directions to frame a policy or plan on rooftop greening in Korea. Besides literature studies, questionnaire survey to Korean and Japanese experts on rooftop greening were done. As results, the annual creation areas, the types and the scales of rooftop greening in Seoul and Tokyo until 2007 were analysed and the satisfaction on the creation areas and technologies, the preference types, the present levels of and the most important parts among policies (support systems), technologies (creation methods), materials, maintenances and user programs for the development or expansion of rooftop greening in Korea and Japan were compared. The creation areas of rooftop greening in Seoul until 2007 was around 15% in Tokyo but the increasing rate of those in Seoul was faster than in Tokyo. Korean needs for the improvement on the rooftop greening systems and technologies were higher than Japanese, but both desired the expansion of rooftop greening areas in both countries. Korean preferred semi-intensive rooftop greening system but Japanese preferred intensive system. Korean and Japanese rooftop greening experts preferred policies (support systems) and technologies (creation methods) for the most important part for the development or expansion of rooftop greening in both countries.

• Steel and Composite Structures
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• v.20 no.4
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• pp.777-799
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• 2016

One of the major components for performance based seismic design is accurate estimation of critical seismic demand parameters. While nonlinear seismic analysis is the most appropriate analysis method for estimation of seismic demand parameters, this method is very time consuming and complex. Single mode pushover analysis method, N2 method and multi-mode pushover analysis method, modal pushover analysis (MPA) are two nonlinear static methods that have recently been used for seismic performance evaluation of few lateral load-resisting systems. This paper further investigates the applicability of N2 and MPA methods for estimating the seismic demands of ductile unstiffened steel plate shear walls (SPSWs). Three different unstiffened SPSWs (4-, 8-, and 15-storey) designed according to capacity design approach were analysed under artificial and real ground motions for Vancouver. A comparison of seismic response quantities such as, height-wise distribution of floor displacements, storey drifts estimated using N2 and MPA methods with more accurate nonlinear seismic analysis indicates that both N2 and MPA procedures can reasonably estimates the peak top displacements for low-rise SPSW buildings. In addition, MPA procedure provides better predictions of inter-storey drifts for taller SPSW. The MPA procedure has been extended to provide better estimate of base shear of SPSW.

• Journal of Environmental Science International
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• v.27 no.10
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• pp.831-844
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• 2018

Riverbank Filtration (RBF) is a kind of indirect artificial recharge method and is useful in obtaining higher-quality source water than surface water when procuring municipal water. This study evaluated optimal riverbank filtered water and the productivity of the radial collector wells on Ttansum Island in the area downstream of the Nakdong River, where Gimhae City is constructing a municipal water plant for the purpose of acquiring high-quality water. The RBF wells are planned to provide water to the citizens of Gimhae City through municipal water works. Groundwater flow modeling was performed with the following four scenarios: (a) 9 radial collector wells, (b) 10 radial collector wells, (c) 10 radial collector wells and two additional vertical wells, and (d) 12 radial collector wells. This study can be useful in determineing the optimum production rate of bank filtrated water not only in this study area but also in other places in Korea.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.18 no.6
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• pp.15-25
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• 2015

The growth of impermeable layers in the city center due to today's urban development is emerging as a major cause of urban heat island effects as well as recurring inland flood damages. In order to cope with such disasters caused by climatic changes, an artificial ground afforestation system is suggested as a fundamental solution that addresses both water environment and heat environment. For the afforestation system to replace the current disaster prevention facilities, quantitative performance verification through related numerical analysis models and actual survey monitoring is necessary. Therefore, this study seeks to propose the performance predication method for the heat environment of the afforestation system by looking into correlations between measurements by physical vegetation indicators such as LAI and FVC and forecasts from FASST, a vegetation canopy model used by US Corps of Engineers.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.9
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• pp.787-792
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• 2007

To understand the effects of forest fires on polymer insulators for transmission lines, the forest fire simulation tests were performed with polymer and porcelain insulators at Gochang testing center. These tests consisted of energizing 90 kV at line-to-ground voltage of 154 kV lines and open flame rising up to $600-630^{\circ}C$ as being measured at insulator surface. Mechanical and electrical characteristics such as specific mechanical load, leakage current, low frequency dry flashover voltage and impulse flashover voltage were analyzed for the polymer insulators before, during and after simulation tests compared with porcelain insulators. At the end of fire simulation tests, there was no detrimental deterioration of any insulators. All insulators passed the criteria of KEPCO specification. This study showed that forest fire simulation had no impact on polymer insulators.

• Journal of the Korean Institute of Landscape Architecture
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• v.32 no.1
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• pp.139-156
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• 2004

All Papers on Ecological Landscape Degign in KILA from 1973 to 2003 are listed herein for finding research issues and trends. The emerging field of Ecological studies of landscape design is based on Landscape Ecology and Watershed Ecology, the Principles of which can be applied to surveying and evaluation, Planning and design, construction and management focusing preservation of wildlife habitat and niche. This field can be classified into six categories: 1. Sustainable site planning and index, 2. Ecological planning process and regulation, 3. landscape ecology and biotope map, 4. Watershed and eco corridor project, 5. Urban forestry and environment, and 6. artificial ground and restoration ecology. The following is the summary of the findings from Paper review: 1. Sustainable index shall be studied about more specified sites. Water recycling facilities, and reservation wet land need to be studied. 2. Policy and legislation research on Ecological design shall be researched by expanding of the application field. Nature park planning and management fields shall be considered as the main theme of green networking Parts. 3. Landscape Ecological studies should be connected to practical surveying data, e.g. the eco-maps published by Environment Ministry. Traditional culture and science should be joined with the modem science. 4. Eco-corridor planning will go with the scenarios and theories of watershed ecology. 5. Urban forestry shall be studied with the wildlife's behavior and habitat. 6. Restoration engineering techniques should be reconsidered with the wildlife's existence and environmental affiliation.

• Journal of the Korea Fashion and Costume Design Association
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• v.4 no.1
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• pp.173-183
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• 2002

The orchid has a very elegant color and various forms in the nature or the ground for human life and the mother of life, The purpose of this study is to express some creative formative art by using the orchid as motive, and thereby, suggest the possibility of an artistic modern costume design by reviewing the texture of the materials. The results of this study can be summarized as follows; First, it was confirmed through this study that the orchid with diverse forms and colors can be used as design motive in almost infinitely diverse ways, and that all the artificial forms or structures contain the elements of natural beauty. Second, the luxurious and rich sense of orchid‘s color can be maximized by using the complementary contrast effect of the dyeing technique and the color gradation effect through harmony among similar colors. Third, a high value-added costume can be created to meet modern men’s aesthetic desire by using such embroidery techniques as crochet, weaving, dyeing, beads embroidery and art flower. Fourth, different effects of texture can be rendered by using different materials of various textures and characteristics. In addition, the possibility of creative expression for costume as formative art can be enhanced by expanding the expressions of the materials.

• Journal of Biosystems Engineering
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• v.32 no.3
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• pp.145-152
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• 2007

Uniformity of spray deposit is one of the important factors in spray performance affecting efficacy of pest management. Distributions of spray deposit on artificial targets were measured and analyzed to enhance the efficiency of spray application. The research was studied to understand the deposition characteristics of spray droplets and to determine the optimum conditions of chemical application. The deposit and its pattern by the lower fan speed was more uniform and higher than that by the higher fan speed. The upward blasting distance was limited within 3 m, but the limit to the ground level was expanded the distance more than 3.5 m because of the accumulated droplets. When the fan speed was higher at the distance of 2.5 m, deposit reached to maximum. When the distance increased, deposit was getting lower. At the both fan speeds, the deposit was concentrated below $30^{\circ}$ because of the gravitation and the resistance of wind. This research can be useful in designing an orchard sprayer and its operation for various tree canopies. To achieve a uniform distribution of deposit using the air-blast type orchard sprayer, the application rate from the middle boom should be increased as the air velocity to the upward increased. The spray rate to the side boom should be limited in a minimal level.