• Resources Recycling
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• v.26 no.5
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• pp.61-66
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• 2017

Vanadium Dioxide has been investigated for use as a "spectrally-selective" window coating to block infrared transmission and reduce the loss of building interior heat through windows. The preparation of thermochromic $VO_2$ powder by the reductive reaction with hydrogen was studied. The reductive reaction method has many advantages of easy and mass production of $VO_2$ powder according to controlled reaction without semi-conductor equipments like sputter and beam evaporator. The reaction temperature, time, concentration of reductive gas, post-annealing condition and W addition as dopant would affect the characterization of $VO_2$ powder and its thermochromism. Many applications for electrical device and energy-saving technologies is expected.

• Korean Journal of Remote Sensing
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• v.22 no.6
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• pp.601-612
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• 2006

This study proposes RAG (Region Adjancency Graph)-based image segmentation for large imagery in remote sensing. The proposed algorithm uses CN-chain linking for computational efficiency and multi-window operation of sliding structure for memory efficiency. Region-merging due to RAG is a process to find an edge of the best merge and update the graph according to the merge. The CN-chain linking constructs a chain of the closest neighbors and finds the edge for merging two adjacent regions. It makes the computation time increase as much as an exact multiple in the increasement of image size. An RNV (Regional Neighbor Vector) is used to update the RAG according to the change in image configuration due to merging at each step. The analysis of large images requires an enormous amount of computational memory. The proposed sliding multi-window operation with horizontal structure considerably the memory capacity required for the analysis and then make it possible to apply the RAG-based segmentation for very large images. In this study, the proposed algorithm has been extensively evaluated using simulated images and the results have shown its potentiality for the application of remotely-sensed imagery.

• Journal of Digital Convergence
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• v.17 no.10
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• pp.321-327
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• 2019

The purpose of this study is to develop a smart device-based Language Rehabilitation Program (LRP) to improve communication ability for the patients with language disability. The content of the LRP includes a variety of semantic categories and grammatical elements and consists of 17 semantic categories, 29 tasks and 3780 items to improve comprehension/production ability at word level, semantic category level, sentence level and discourse level. We developed LRP as a Windows-base management program and an Android-base language rehabilitation application. LRP was developed into an application for smart devices, providing real-time delivery of training contents, measurement and database of training task results, and patient progress and monitoring. A follow-up study will be conducted on the verification of the language rehabilitation effect using LRP by patients with language disability.

• Journal of the Korean Society of Propulsion Engineers
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• v.17 no.2
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• pp.39-45
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• 2013

Basically, in order to apply solid propellant as ignition source to high energy metal particle combustion system, we analyzed combustion characteristics of the HTPB/AP/Al, HTPE/AP/Al propellants by using a strand burner. The propellants were tested in a high-pressure windowed strand burner, which was pressurized up to 300 psia with pure argon gas. Strand burner was visualized with two quartz windows and ignition was accomplished by a 10 W $CO_2$ laser. The burning rate of propellant was measured with high-speed camera method for frame analysis and photodiode method for combustion time analysis. Emission spectrum was measured with spectrometer at 300 nm ~ 800 nm and 1500 nm ~ 5000 nm and then we analyzed species during propellant combustion.

• Journal of the Korea Convergence Society
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• v.12 no.9
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• pp.323-330
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• 2021

Purpose: This study aimed to identify the maternal functioning and related factors among early postpartum women. Methods: In this cross-sectional study, 243 women recruited from three women's hospitals. Participants completed a structured questionnaire in on-line or off-line between 6 and 12 weeks postpartum. Data were analyzed using descriptive statistics, the t-test, analysis of variance, Pearson correlation coefficients, and stepwise multiple regression with SPSS for Windows ver. 25.0. Results: The mean score for the maternal functioning was 73.28±16.78 out of 120 points. Maternal functioning was associated with postpartum depression (r=-.57 p<.001), and spousal and family support (r=.54, p<.001). According to the stepwise multiple regression, postpartum depression (β=-0.43, p<.001), spouse and family support (β=0.39, p<.001), employment (β=0.12, p=.012) and delivery method (β=-0.10 p=.026) had a significant relationship with the maternal functioning among postpartum women. These variables had an explanatory power of 49.0% for maternal functioning. Conclusion: It is necessary to develop and implement a maternal intervention program focused on alleviating postpartum depression and improving spouse and family support. This study will be the starting point for various studies by identifying the maternal functioning of postpartum women for the first time in Korea.

• Tunnel and Underground Space
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• v.29 no.2
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• pp.89-107
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• 2019

Rock joints have an extremely important role in analyzing the mechanical stability and hydraulic characteristics of rock mass structures. Most rock joint parameters are generally indicated as a distribution by statistical techniques. In this research, calculation technique of Joint Center Volume (JCV) is analyzed, which is required for estimating the size distribution having the largest uncertainty among the joint parameters, then a new technique is proposed which is applicable regardless of the shape of survey window. The existing theoretical JCV calculation technique can be applied only to the plane window, and the complete enumeration techniques show the limitations in joint trace type and analysis time. This research aims to overcome the limitations in survey window shape and joint trace type through calculating JCV by using Monte Carlo simulation. The applicability of proposed technique is validated through the estimation results at non-planar survey windows such as curved surface and tunnel surface.

• Journal of the Korea Convergence Society
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• v.12 no.2
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• pp.147-154
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• 2021

This study focused on the fitting window structure provided by the virtual fitting service web page. We analyzed the current cases and identified the user's needs for the service through usability assessment, survey, and FGI experiments. As a result of the design, the fitting window of the existing web page was opened at the same time as the site was accessed to improve the hassle of using the icons due to their small size and poor visibility. In the case of fitting windows, the problem of information delivery was supplemented so that even the initial user could understand the fitting map of the existing method, and additional items needed for user propensity were provided so that the service could be used accurately and easily. As a result of this study, it can be used as a basic research material in future virtual fitting service studies and is expected to provide good implications to fashion marketers.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.14 no.1
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• pp.113-119
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• 2004

Exponentiation is widely used in practical applications related with cryptography, and as the discrete log is easily solved in case of a low exponent n, a large exponent n is needed for a more secure system. However. since the time complexity for exponentiation algorithm increases in proportion to the n figure, the development of an exponentiation algorithm that can quickly process the results is becoming a crucial problem. In this paper, we propose a parallel exponentiation algorithm which can reduce the number of rounds with a fixed number of processors, where the field elements are in GF($2^m$), and also analyzed the round bound of the proposed algorithm. The proposed method uses window method which divides the exponent in a particular bit length and make idle processors in window value computation phase to multiply some terms of windows where the values are already computed. By this way. the proposed method has improved round bound.

• Journal of the Korea Fashion and Costume Design Association
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• v.23 no.2
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• pp.133-146
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• 2021

It is important to conduct an anthropometric study to develop garment patterns to accommodate the changes found in the body size and type of men in their 30s, to effectively address fit dissatisfaction. Thus, this study aims to explore changes in the lower body sizes and body types of men in their 30s, and provide basic measurements for designing pants patterns. For this purpose, key anthropometric dimensions for the lower body of men in their 30s, which were acquired by the 6th (2010) and 7th (2015) survey conducted by Size Korea, were analyzed using SPSS 24.0 for Windows. Independent sample t-tests were conducted on major lower body sizes to track changes over time. Factor and cluster analyses were used to classify lower body types. From the comparison of the 6th (2010) and 7th (2015) surveys, it was found that the overall lower body size of men in their 30s were increasing in the height-related aspects, circumference, thickness, and width-as well as body weight and BMI. The five factors were derived to determine the typical lower body types of men in their 30s and the body types were classified into three categories through cluster analysis: (1) those with the largest body size, body volume, and obesity, (2) those with smallest body size, lower body volume, and obesity degree, visually the most skinny type, (3) those with BMI and weight that are the smallest, like Type 2, but the main circumference of the lower body is lower. In order to visually look at the statistical analysis, results were presented by producing a avatar based on the main lower body values.

• Women's Health Nursing
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• v.26 no.4
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• pp.318-325
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• 2020

Purpose: The purpose of this study was to identify the influence of self-differentiation, psychological discomfort, and marital dyadic adjustment on maternal-fetal attachment in primigravida. Methods: In total, 108 primigravida participated in this descriptive correlational study. The participants answered self-report questionnaires. Data were collected from January to May, 2020, and were analyzed using descriptive statistics, the t-test, analysis of variance, Pearson correlation coefficients, and hierarchical multiple regression with SPSS for Windows ver. 23.0. Results: The mean age of the primigravida was 31.66 years. The mean score for the degree of maternal-fetal attachment was 76.81 out of 96 points. Participants' scores for maternal-fetal attachment differed significantly based on age (t=2.08 p=.039) and marital status (t=2.05, p=.043). Maternal-fetal attachment was significantly negatively correlated with psychological discomfort (r=-.39, p<.001), and significantly positively correlated with self-differentiation (r=.36, p<.001) and marital dyadic adjustment (r=.36, p<.001). Self-differentiation explained 24.1% of variance in participants' maternal-fetal attachment, and its effect was statistically significant (F=7.79, p<.001). Conclusion: In primigravida, more self-differentiation was associated with stronger maternal-fetal attachment. To strengthen maternal-fetal attachment in primigravidae, educational program that increases the level of self-differentiation and minimizes psychological discomfort may be helpful for first time pregnant women. Additionally, it is recommended to provide nursing interventions to encourage couples to work together throughout the gestational period.