• Journal of the Korean Geotechnical Society
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• v.38 no.3
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• pp.35-42
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• 2022

The N-value from the Standard Penetration Test (SPT), which is one of the representative in-situ test, is an important index that provides basic geological information and the depth of the bearing layer for the design of geotechnical structures. In the aspect of time and cost-effectiveness, there is a need to carry out a representative sampling test. However, the various variability and uncertainty are existing in the soil layer, so it is difficult to grasp the characteristics of the entire field from the limited test results. Thus the spatial interpolation techniques such as Kriging and IDW (inverse distance weighted) have been used for predicting unknown point from existing data. Recently, in order to increase the accuracy of interpolation results, studies that combine the geotechnics and deep learning method have been conducted. In this study, based on the SPT results of about 22,000 holes of ground survey, a comparative study was conducted to predict the depth of the bearing layer using deep learning methods and IDW. The average error among the prediction results of the bearing layer of each analysis model was 3.01 m for IDW, 3.22 m and 2.46 m for fully connected network and PointNet, respectively. The standard deviation was 3.99 for IDW, 3.95 and 3.54 for fully connected network and PointNet. As a result, the point net deep learing algorithm showed improved results compared to IDW and other deep learning method.

• The Journal of the Acoustical Society of Korea
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• v.42 no.3
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• pp.243-249
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• 2023

The occurrence of cavitation on the propeller is directly linked to the naval ship's survivability, and it is necessary to design a propeller shape that delays the cavitation inception. However, the propeller cavitation can occur under various operating conditions, thus it is important to identify whether the propeller cavitation exists during operation as well as in the design phase. To this end, it is necessary to use noise or vibration signals on board to monitor the cavitation inception. In this study, a hydrophone and an accelerometer were installed on the ship hull right above the propeller to compare the performance of analyzing cavitation inception between acoustic and vibration signals. Also, a high speed camera was used to visually observe the occurrence of cavitation through an observation window. The measured results showed that the spectral shapes between acoustic and vibration signals were different, but the level increases at each frequency band and the overall level of the frequency band from 1 kHz to 10 kHz showed a similar tendency. The Detection of Envelope Modulation On Noise (DEMON) analysis also showed similar results for both acoustic and vibration signals, confirming that both hydrophones and accelerometers can be utilized in the analysis of cavitation inception.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.23 no.3
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• pp.159-166
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• 2023

This study analyzed what consumer characteristics affect the experience of using overseas direct purchase at a time when the overseas direct purchase market is rapidly increasing and consumers' interest in overseas direct purchase is increasing accordingly. For the study, personal data from the 2022 Korea Media Panel Survey were used, and data from 6,734 people who responded "yes" or "no" to whether or not to use overseas direct purchase among 9,941 total respondents were used for analysis. In addition, three variables (demographic, media utilization status, values and lifestyle) were selected among the items of the Korea Media Panel Survey. First, general characteristics were analyzed fo 6,734 people, then, Chi-square test and t-test were performed for comparative analysis between each variable according to the use of overseas direct purchase. Finally, logistic regression analysis was performed to identify the factors affecting overseas direct purchase. As a result of the analysis, 4 out of 5 demographic variables, 2 out of 3 media utilization variables, and 3 out of 7 values and lifestyle variables were derived as decisive factors for using overseas direct purchase. These results can be used to establish marketing strategies that can increase the use of consumers through domestic shopping malls, such as providing differentiated services for the sale of overseas direct shopping products on domestic shopping sites.

• Journal of Applied Biological Chemistry
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• v.65 no.1
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• pp.7-15
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• 2022

Volatile and non-volatile metabolite profiles of sugar-immersed raspberry liquid during different storage periods were analyzed and comparative analysis with their general characteristics, antioxidant activity, and sensory quality was evaluated to better understand the effect of the storage period on the quality of ugar-immersed raspberry liquid. During storage, a browning reaction occurred, resulting in a change in color and the production of volatile compounds. At the beginning of storage, sucrose was completely decomposed into fructose and glucose, and the sweetness was rapidly reduced, but the increase in succinic acid increased the sour taste. Most volatile compounds increased with an increase of the storage period, and especially, the contents of citronellol, octanoic acid, and hexanoic acid, which are known as antioxidants, showed the highest content in 10 day-sample, showing the highest antioxidant activity at this time. Although a further study on bacterial profiles and browning reaction during the storage will be needed, the results of this study showed that the quality of sugar-soaked raspberry extract was significantly affected by the storage period and can be used as basic data for commercialization of ugar-immersed raspberry liquid.

• Journal of Digital Convergence
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• v.20 no.3
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• pp.517-527
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• 2022

This study aimed to compare changes in cognitive function, depression and ability to perform activity of daily living (ADL) in patients with dementia, mild cognitive impairment (MCI), and ischemic stroke (IS) and to identify factors associated with changes in instrumental ADL. A total of 86 patients (dementia=30, MCI=32, and IS=24) were included to analyse cognitive function, depression, and basic and instrumental ADL obtained at the time of diagnosis and 1 year after baseline. Repeated measures analysis of variance and multiple linear regression were used. A significant group by time interaction was found in executive function (p=.037) and instrumental ADL (p=.023) across groups. The MCI group has little change in executive function and instrumental ADL from the baseline to 1 year after diagnosis while other two groups showed changes with the dementia group showing declines and the group of IS having improvement in these factors over time. Changes in executive function(p=.030) and basic ADL (p<.001) explained 26.9% in the variance of changes in instrumental ADL. These findings showed a different changing pattern in executive function during the first year after diagnosis of dementia, MCI, and IS which have cognitive changes as their main symptoms, probably leading to a different changing pattern in instrumental ADL. Healthcare professionals should routinely assess for executive function and instrumental ADL problems and intervene to maintain and improve these functional outcomes immediately after disease.

• Anayses & Alternatives
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• v.2 no.1
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• pp.5-29
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• 2018

Models of South-North Korean economic integration have the problem of circular reasoning. While many studies argue that South-North Korean economic integration would contribute to alleviate security risks in the Korean peninsular, they emphasize the success of any economic model of inter-Korean economic integration is subject to favorable geo-political and security environment. It is a failure in distinguishing between goals and constraints. After identifying three major goals of South-North Korean economic cooperation, this study shows the trilemma among the goals; they are 1) formation of a complete economic community, 2) maintaining independent sovereignty of the two Koreas, 3) promotion of mutual economic interests. The trilemma suggests that it is theoretically impossible to achieve the above three goals at the same time. Only two goals are achievable simultaneously. This study argues that the most practical option is to pursue the combination of goals 2) and 3) considering the complex political and security environment around the Korean peninsular. Recognizing that North Korea is the least developed country in the Northeast Asia region, South Korea's initiatives for inter-Korean economic cooperation should focus on assisting industrialization and integration of the North Korea economy into the Northeast Asian regional production sharing structure. In view of the 'flying geese model' of the sequential industrialization in the region, the least developed economic status of North Korea can partially be explained by its failure to participate in the production network in the region as well as lack of effective implementation of appropriate industrial policy. Therefore, promotion of industrialization of North Korea should be the immediate goal of economic cooperation between North and South Korea. It is an interesting fact that North Korea has rapidly expanded its apparel exports in recent years. It could mean that the North Korean economy is actively responding to the dynamics of international comparative advantage structure, although the production activities are limited to exports to China since the closure of the Gaesung Industrial Complex. The recent increase in apparel export is a starting point for incorporating the Easy Import Substitution fulfilling both domestic and neighboring regional demand of North Korea. It could help integrate North Korea's industry into the production network of Northeast Asia. An immediate policy implication is that the economic cooperation between the two Koreas should focus on facilitating this process and supporting North Korea's industrial policy through South Korea's contribution of capital, technology, and service intermediary inputs.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.6 no.9
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• pp.201-210
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• 2016

The purpose of this study is to explore the process of multicultural perception change of university students who have participated in multicultural mentoring. From May to December of the year 2015, the researcher conducted continuous e-mail interviews as well as in-depth interviews with mentors who participated in multicultural mentoring at I university. The interview contents were transcribed and comparative analysis was done. The result of the study is as follows. The process of multicultural perception change of mentors were discovered to be change in stereotypes, prejudice and ideas on multiculture, difference detection and social desire. They realized that stereotypes and prejudice were the errors of generalization due to their ideas on multiculture which were developed through media. Through mentoring activities the mentors reflected on the inherent negative ideas on multiculture, thus changing their ideas and thoughts. Also, the difference detection acknowledged cultural diversity along with the understanding of the cultural environment of mentees. Social desire expressed their wish for the change of perception in the cultures of others along with the positive change of multicultural perception through mentees. Thus, it was discovered that multicultural mentoring activities are sufficient prerequisites to change the social perception of multiculture from personal interest.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.7 no.8
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• pp.189-199
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• 2017

The purpose of this study is to compare the grid usage that is common to Leonardo da Vinci and J.N.L. Durand in the process of designing the architectural plan. In the days when there was no proper measurement tool, auxiliary lines relied entirely on the architect's personal mindset and design convenience. Therefore, it is considered that studying the auxiliary lines drawn by the architects will be useful for studying the human perception system. Among auxiliary lines, the grid has been used by many architects. Leonardo da Vinci and J.N.L. Durand are famous. However, these two show a significant different grid usage. As auxiliary grid and space ares added the center of the Leonardo da Vinci grid continues to move, and the grid in his sketch is becoming a building space itself. So I call it 'conceptual grid'. In the case of J.N.L. Durand, the one center of the grid is always at the center of the drawing. That is, all the positions of the grid can be determined in phase around a common point, and all of the same specifications are assumed. The grid is a kind of filter. That's why his grid is a visual abstraction of the process of thinking. In this paper, I will call the grid of J.N.L. Durand as 'abstract grid'.

• Science of Emotion and Sensibility
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• v.25 no.4
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• pp.45-52
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• 2022

Recently, interest in and demand for sensors that recognize physical activity and their products are increasing. In particular, the development of wearable materials that are flexible, stretchable, and able to detect the user's biological signals is drawing attention. In this study, an experiment was conducted to improve the dip-coating efficiency of a single-walled carbon nanotube dispersion solution after fine holes were made in a hydrophobic material with a micro needle. In this study, dip-coating was performed with a material that was not penetrated, and comparative analysis was performed. The electrical conductivity of the sensor was measured when the sensor was stretched using a strain universal testing machine (Dacell Co. Ltd., Seoul, Korea) and a multimeter (Keysight Technologies, Santa Rosa, CA, USA) was used to measure resistance. It was found that the electrical conductivity of a sensor that was subjected to needling was at least 16 times better than that of a sensor that was not. In addition, the gauge factor was excellent, relative to the initial resistance of the sensor, so good performance as a sensor could be confirmed. Here, the dip-coating efficiency of hydrophobic materials, which have superior physical properties to hydrophilic materials but are not suitable due to their high surface tension, can be adopted to more effectively detect body movements and manufacture sensors with excellent durability and usability.

• 한국체육학회지인문사회과학편
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• v.57 no.1
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• pp.135-149
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• 2018

The aim of this study was to determine importance of coaching knowledge and university curriculum from the perspectives of physical activity lectures. This study focused on importance of knowledge on physical activity education, experiences of teaching methods classes and training programs, comparative importance of coaching knowledge and university education, perceived difficulties in coaching and solutions, and coaching related knowledge needed to learn in their university training. Data were collected from 112 physical activity lectures working in commercial, community, and school settings. Results from qualitative and quantitative data revealed that they perceived knowledge of sport pedagogy very important when coaching their classes or members. While they took fewer coaching methods classes in their universities, their experiences from the classes were helpful in coaching. The differences between perceived importance and the level of education were greater in the areas including consultation of members, management of membership, and communication with members. They tried to solve difficulties by themselves or wanted to discuss with colleagues and employers. If possible they also wanted to seek educational consulting. In order to acquire adequate coaching knowledge the lectures need to received systematic training regarding sports skills teaching methods, theories and practices of various sports, and planning of sports skills coaching while they were in university programs.