• Journal of the Korean Society for Nondestructive Testing
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• v.34 no.3
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• pp.254-259
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• 2014

A pressurized heavy water reactor (PHWR) core has 380 fuel channels contained and supported by a horizontal cylindrical vessel known as the calandria, whereas a pressurized water reactor (PWR) has only a single reactor vessel. The pressure tube, which is a pressure-retaining component, has a 103.4 mm inside diameter ${\times}$ 4.19 mm wall thickness, and is 6.36 m long, made of a zirconium alloy (Zr-2.5 wt% Nb). This provides support for the fuel while transporting the $D_2O$ heat-transfer fluid. The simple tubular geometry invites highly automated inspection, and good approach for all inspection. Similar to all nuclear heat-transfer pressure boundaries, the PHWR pressure tube requires a rigorous, periodic inspection to assess the reactor integrity in accordance with the Korea Nuclear Safety Committee law. Volumetric-based nondestructive evaluation (NDE) techniques utilizing ultrasonic and eddy current testing have been adopted for use in the periodic inspection of the fuel channel. The eddy current testing, as a supplemental NDE method to ultrasonic testing, is used to confirm the flaws primarily detected through ultrasonic testing, however, eddy current testing offers a significant advantage in that its ability to detect surface flaws is superior to that of ultrasonic testing. In this paper, effectiveness of flaw detection and the depth sizing capability by eddy current testing for the inside surface of a pressure tube, will be introduced. As a result of this examination, the ET technique is found to be useful only as a detection technique for defects because it can detect fine defects on the surface with high resolution. However, the ET technique is not recommended for use as a depth sizing method because it has a large degree of error for depth sizing.

• Journal of Fashion Business
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• v.22 no.3
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• pp.122-142
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• 2018

In the virtual fitting system, the use of a 3D avatar is not a simple garment model, but it should be able to reproduce the size and shape of the customer using a fitting system. Although various virtual fitting systems have their own 3D avatar sizing systems and provide 3D avatars that match the size of the customer, there are limitations in realizing the actual body shape in actual use by the consumer. The purpose of this study is to realize a 3D avatar with excellent size and conformity for customer use. Therefore, this study aims to provide basic data for the formation of a 3D standard avatar of Korean women aged in their 20's, by comparing and analyzing the degree of the consumer user friendly system change of a body type, and the consumer's ability in selecting a consumer representative body type. Based on the survey data of 'Size Korea' conducted from 2004 to 2015 at three times, we examined the change of body shape over 10 years. Then, based on the results of 6th and 7th data, 4 factors of the concurrent body shape change of women of the consumer demographic studied were selected through the use of a factor analysis. Following this analysis, the 4 extracted factors were clustered again and finally released 7 representative body types, which were obtained based on height and weight. The size of each representative figure is derived by the use of a regression analysis, and it is used as a basic data for 3D avatar formation of the virtual fitting system.

• Journal of the Korean Wood Science and Technology
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• v.28 no.1
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• pp.71-79
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• 2000

Two linerboards consisting of corrugated board were coated with oxidized starch solutions to investigate the change of their properties and analyze the effect of coating on them. The coating of linerboards with oxidized starch resulted in improvement in the properties related to corrugated board properties by increasing fiber bonding and rigidity. The improvement of ring crush strength by coating was greater in inside linerboard than in outside linerboard. Burst index of linerboards rapidly increased with an initial increase of coating weight, but as the coating weight further increased, there was no increase in burst index. Coating on linerboards with oxidized starch at low coating weight improved stiffness of them. There were no significant changes in tearing resistance of linerboards by coating of oxidized starch. The coating resulted in increase in air resistance and sizing degree of linerboards.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.42 no.1
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• pp.64-73
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• 2010

This study was conducted to modify the surface properties of papers by formation of hydrophobic self-assembled monolayer(SAM) on paper surface with silanes. A base paper I(0.5% AKD) and base paper II(1.0-1.5% AKD) were reacted with silanes(PFDTES, DMDCS, MODDCS) by immersion method and vapor deposition method. Hydrophobic SAMs(contact angle value>$120^{\circ}C$) were obtained on all papers after treatment with $10^{\mu}l$ PFDTES for 15min, with $50^{\mu}l$ DMDCS for 30min, with $50^{\mu}l$ MODDCS for 300min. When applying PFDTES to paper surface, lower silane concentration and shorter reaction time were required, whereas MODDCS with long alkyl chain required the longest reaction time of 300min. The st$\ddot{o}$ckight sizing degree of silane treated papers were increased between 105sec(base paper I) and 130sec(base paper II). The wet tensile strength of PFDTES-treated base papers(I, II) increased by 10-34% after SAM formation. However, the wet tensile strength of the DMDCS-treated base paper(I) was found to decrease from 0.067kN/m to 0.038kN/m; this may due to the cellulose degrading as a result of generated hydrogen chloride when hydroxyl group of cellulose were reacted with DMDCS. No apparent changes of PPS roughness on silane-treated papers are observed. The ATR-IR spectrum showed absorption peak located at 465 and 1200cm-1 which can be assigned to the Si-O-C asymmetric stretching and Si-O-C bonds, respectively.

• The Journal of the Convergence on Culture Technology
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• v.9 no.6
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• pp.257-262
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• 2023

As part of their marketing policy, some suppliers allow retailers a period of credit in anticipation of increasing demand for the products they supply. The opportunity to defer payments on products through credit transactions has the effect of reducing retailers' inventory investment costs, and as a result, retailers determine selling prices in anticipation of increased demand from buyers. This study aims to analyze the inventory model that determines the retailer's selling price and EOQ(Economic Order Quantity) under the assumption that the buyer's demand is an exponentially decreasing function of the retailer's selling price in the credit transaction supply chain consisting of suppliers, retailers, and buyers. The products supplied for problem analysis include the case of deteriorating products that deteriorate over time, and the effect of the credit transaction period, the index of price elasticity and the degree of deterioration on the retailer's selling price and EOQ is analyzed.

• Fashion & Textile Research Journal
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• v.21 no.3
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• pp.318-325
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• 2019

This study analyzes current self-nail tips and nail-tip satisfaction. The study method selected from 3 domestic and 3 overseas companies analyzed current self-nail tips based on brand recognition and sales rate. A questionnaire was conducted on 261 adult women in their 20s and 50s about the satisfaction of nail care and self-nail tips. The results are as follows. As a result to analyze the current nail tips, there were products that did not contain the type of nail tip or the composition and ingredients of the glue. An online survey of the sizes of the current nail tips indicated differences in the sizing system method and that the presented sizes are different. The response rate was the highest for the survey results on why self-nail tips were preferred for respondents who prefer self-nail tips because the price was cheap. The reason why they did not prefer self-nail tips was that the degree of completeness was lower and the fitness was not good. In addition, it showed a high response rate in that the adhesive strength was poor and the size did not fit the nails. Therefore, it is necessary to develop a size for nail types by ergonomic design and develop a self-nail tip that can reduce nail damage.

• Journal of the Korean Home Economics Association
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• v.41 no.3
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• pp.1-15
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• 2003

This study was conducted to analyze the actual wearing conditions and body fit preferences of the middle-aged women's ready-to-wear lower body clothing. The aim was also to analyze lower body recognition, lower body satisfaction, fit preferences and size satisfaction according to age and degree of girth size. A questionnaire was developed and administered to 300 middle-aged women aged 34 to 59. Statistical tests such as descriptive analysis, crosstabs, and X²-tests were conducted to analyze the data and ascertain the differences between the ages. Lower body satisfaction and recognition were compared by T-test. Also, Anova was used to analyze lower body recognition, satisfaction, fit preferences, and size satisfaction according to age and degrees of girth size. The results indicated that women aged 50 to 59 were more dissatisfied with the ready-to-wear sizing system and because of their body shapes had changed, their need for a larger size range system had also increased. Moreover, the element that most affected their purchase of ready-to-wear lower body clothing was the design followed by the size. The women, especially of the ages 50 to 59, showed a tendency to he dissatisfied with their lower bodies and they recognized that their lower bodies had thickened compared to women aged 34 to 39 and 40 to 49. Analysis of body satisfaction, recognition, and fit preference according to girth size showed that the group of larger girth size recognized that their lower bodies were thicker and were more dissatisfied and preferred looser fittings than the groups of smaller women.

• Korean Journal of Construction Engineering and Management
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• v.19 no.5
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• pp.43-52
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• 2018

Generally, research on construction cost has been done mostly regarding its direct cost, thus model regarding indirect cost lacks attention. This research seeks to introduce a model to predict on-site overhead cost for apartment construction projects, which constitutes a big portion in Korean construction industry. We devised an equation of 9th degree via curve-fitting, using multiple on-site actual expense data, which can be used to calculate per-progress rate, per-day on-site overhead cost. We further show prospective usage of the model by applying it on construction projects sizing about 30 billion won. Regarding the fact that previous studies could not recognize pattern changes of a total on-site overhead cost, this model is worthy of its conveniency and thoroughness, as well as providing reasonal ground for its derivation in predicting on-site overhead cost of apartment construction projects.

• Journal of the Korean Society of Clothing and Textiles
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• v.33 no.12
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• pp.1853-1861
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• 2009

Body sizing of has been recognized as an important element affecting the degree of customer satisfaction in the apparel industry. Recent developments in IT technologies have enabled more studies in custom-made apparel systems that comply with the diverse demands from customers in many countries. Diverse methods to obtain personal physical size are being studied. This study estimates the accuracy by developing the system in which the data of length and girth can be calculated through changing a modeling by comparing the data with circular 3-dimensional physical configuration data. This information was computed from the process (such as the conversion to a standardize image) which utilizes the image capture of 2-dimensional three sides (front, side, and rear), contour tracing, and key-node selection and by realizing it in the real world.

• Journal of Korean Society of Disaster and Security
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• v.11 no.1
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• pp.31-38
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• 2018

The 99.1% of small dam and most of the levees in Korea are soil dam which can be constructed with lower cost and less effort compared with ones made of concrete. However, they are so vulnerable to overflow. Sudden collapses of these strucrues lead to increase flow rate rapidly, which may cause catastrophic problems in downstream regions. In this study, the experimental study on the collapse delay effect of riprap that was laid on slope of soil levee was carried out. A prismatic rectangular open channel was used and three different sizes of the riprap were installed on slope of a scaled earth dam. A new formula for the collapse time of the levee with the installation of riprap was presented, using the previous researches and the dimensional analysis. In this process, an unsteady flow condition was considered to derive the deviation time of the riprap. And additional experiments were conducted to understand the effect of reinforcement of riprap, and it was found that the reinforcement of riprap was more effective than twice sizing of intial riprap. If the collapse time is delayed, EAP (Emergency Action Plan) and forecasting can greatly reduce the degree of flood damage. Also, it will be meaningful that the results of this study are used for river design.