• Nuclear Engineering and Technology
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• v.55 no.9
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• pp.3342-3351
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• 2023

High-density polyethylene (HDPE) pipelines in nuclear power plants (NPPs) have to meet high requirements for seismic performance. HDPE pipes have been proved to have good seismic performance, but joints are the weak links in the pipelines, and pipeline failures usually initiate from the defects inside the joints. Limited data are available on the seismic performance of butt-fusion joints of HDPE pipelines in NPPs, especially in terms of defects changes inside the joints after earthquakes. In this paper, full-scale shaking table tests were performed on a test section of suspended HDPE pipelines in an NPP, which included straight pipes, elbows, and 10 butt-fusion joints. During the tests, the seismic load-induced strain of the joints was analyzed by strain gauges, and it was much smaller than the internal pressure and self-weight-induced strain. Before and after the shaking table tests, phased array ultrasonic testing (PA-UT) was conducted to detect defects inside the joints. The locations, numbers, and dimensions of the defects were analyzed. It was found that defects were more likely to occur in elbows joints. No new defect was observed after the shaking table tests, and the defects showed no significant growth, indicating the satisfactory seismic performance of the butt-fusion joints.

• Journal of the Korean Society of Food Culture
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• v.24 no.1
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• pp.23-32
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• 2009

This study was conducted to generate fundamental data required by food coordinators and food space creators for planning and directing table settings. The results of this study were then used to suggest an ideal model of table settings for Korean-style food equipped with simple, sophisticated, and practical characteristics. Specifically, this study evaluated the importance of hygiene (safety, cleanness, arrangement), decoration (dignity, form, stylishness, presentation of food on plates), naturalness (seasonal beauty, comfortableness, natural beauty), and modernity (modern style, chic style, urban style). These factors were evaluated according to the preference of the table setting and the characteristics of the meeting, which fit various meal cultures, times, places, and objectives. The results of this study indicate that people prefer hygiene and decoration for family meetings (bansang setting), hygiene and modernity for friendly meetings (simple buffet setting), hygiene and decoration for company meetings (simple buffet setting), and hygiene and decoration for academic meetings (tea party). Hygiene and decoration were highly evaluated in most cases, which indicates that individuals at meetings for special purposes give weight to the meeting's atmosphere, but also consider the hygiene and cleanliness of the food.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2001.04a
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• pp.461-467
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• 2001

Shaking table tests were performed with full scale models of stone parapet on the ancient rampart. The objectives of these tests are to study the seismic behavior of the parapet and to obtain quantitative estimation of the intensities of historical earthquakes. Two test models were made based on the structure of the parapet remnant of a mountain fortress in Bukhan-San located in Seoul. Two types of infilling material are considered. The responses to models were tested subjected to three kinds of input motion.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.34 no.1
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• pp.97-102
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• 2011

This study was performed to design and develop an ergonomic equipment for strawberry sorting and packing in agricultural working environments. Potential risk of work related musculo-skeletal disorders associated with farm workers performing strawberry sorting and packing was analyzed through interviews, field surveys, work measurement, and working posture evaluation. For the evaluation of working posture, we used REBA, OWAS, and RULA assessment methods to identify multi-factorial risk factors. Based on the result of comprehensive assessment, a new concept of multi-level rotating table for strawberry sorting and packing was proposed to modify awkward working postures and improve the effectiveness of the farm work. Finally, the characteristics and effectiveness of new equipment was discussed in terms of improvements in productivity, safety, and subjective ratings of farm workers. The results of analysis showed that working conditions improved significantly.

• Journal of Wellbeing Management and Applied Psychology
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• v.7 no.3
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• pp.73-95
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• 2024

Purpose: Since August 2000, the small-scale environmental impact assessment system has prevented indiscriminate development. However, its qualitative reports lack objectivity and consistency. This study analyzes these issues through literature and expert surveys and proposes improvements. Research Methodology: Samples were selected based on regional consultation numbers. Mitigation measures were categorized into qualitative and quantitative factors. Issues were identified, and improvements suggested. The Delphi method helped select evaluation items and propose a scoring table. Results and Conclusions: The Delphi method selected 14 absolute and 22 relative evaluation items, excluding 3 invalid ones. A 100-point scoring table was created, with points assigned based on element significance. A 1-point bonus was added for top-scoring elements to promote eco-friendly planning.

• Journal of the Korean Society of Radiology
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• v.9 no.4
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• pp.219-225
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• 2015

This study aims to evaluates the image quality of CR and DR that are scanned with the use of the attachable carbon heater X-ray scanner table equipped with heating device by measuring SNR and CNR before and after the attachment of the said table. In the aluminum staircase testing, CR increased SNR and CNR when attached with the table, while DR decreased SNR and CNR. In the human-body model phantom testing, CR increased SNR and CNR only in the low-energy low-dose radiation and the high-energy high-dose radiation, but decreased SNR and CNR under all other conditions. In conclusion, the use of such table can make the patient feel comfortable by removing his or her anxiety, thus helping the testing, but in the actual clinical application thereof, if the thickness and material of the bottom film and the protective film, including the carbon heater, are not considered, it affects the picture quality, thereby requiring continuous research on the use of such table.

• Journal of radiological science and technology
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• v.46 no.4
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• pp.295-301
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• 2023

In addition to protocol adjustments during CT examinations, the height of the CT table can also affect image quality. Therefore, this study aimed to investigate the change in image quality depending on the height of the table in brain CT, which accounts for a large proportion of CT examinations, by measuring signal to contrast to noise ratio (CNR) and noise power spectrum (NPS) using the head phantom and evaluating them. The head phantom images were acquired using Philips Brilliance iCT 256. When the image was acquired, the table height was adjusted to 815, 865, 915, 965, 1015, and 1030 mm, respectively, and each scan was performed 3 times for each height. The CNR result showed the highest value at 965 mm, which is the height adjacent to the center of the head phantom. NPS showed the lowest NPS at 915 mm, the center of the head phantom in the low frequency region. From these results, it can be seen that the height of the table in CT examination is closely related to the image quality, and it can be seen the characteristics of image quality according to CT table through quantitative evaluation methods such as CNR and NPS.

• Journal of the Korean Society of Radiology
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• v.11 no.6
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• pp.453-458
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• 2017

Computed Tomography (CT) provides information on the Diagnostic Reference Level Computed Tomography Dose Index (CTDI) and Dose Length Product (DLP) for accurate diagnosis of patients. However, it does not provide a dose change according to the table height for the diagnostic reference level provided by the CT equipment. The purpose of this study was to evaluate the image and dose according to the table height change using phantom (PMMA: Polymethyl Methacrylate) in order to find the optimal image and the minimum dose during computed tomography examination. When examining using a 32 cm PMMA phantom with the same thickness as the abdomen of an adult, there was little change in dose with table height. However, the noise evaluation of the image caused a high fluctuation of noise depending on the table height. and in the case of the 16 cm PMMA phantom, the change of the noise was small, but the dose change was about 30%. In conclusion, the location of the patient and the center of the detector are important during computed tomography (CT) examinations. In addition, table height setting is considered to be important for examinations with optimized image and minimum dose.

• Human Ecology Research
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• v.54 no.3
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• pp.333-349
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• 2016

This study develops and evaluates a game-based lesson plan applied to the 'Food Culture' unit of a high school Home Economics class. We developed, implemented, and evaluated lesson plans for seven periods that contained 'the Korean food table setting card,' 'the world's food culture card,' and the procedure for cards games according to the Analysis, Design, Development, Implementation, and Evaluation (ADDIE) model. 'The Korean food table setting card' consisted of 'the Korean food table setting order card' to easily understand 10 types of Korean traditional daily meals based on pictures and 'the Korean food table setting food card' to easily understand Korean traditional food based on 104 kinds of food picture and quick response (QR) code. 'The world's food culture card' consisted of 'the world's food culture quiz card' to help learners easily understand influential food culture formation factors, features of food culture, typical foods from 16 countries, and 'the world's traditional food card' to help learners easily understand typical foods from 16 countries through 63 kinds of pictures. Respective 'game guides' were also developed. High school students who studied the game-based Home Economics classes and who participated in the 'Food Culture' unit, could easily and enjoyably learn the food culture of Korea (and other countries), actively participate in learning activities, and understood the content of food culture. In addition, they evaluated that the game-based instruction was easy to remember with minimal memorizing.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2009.10a
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• pp.19-20
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• 2009