• Journal of the Microelectronics and Packaging Society
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• v.24 no.2
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• pp.61-67
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• 2017

As transistor density increases rapidly, a heat flux from IC device rises at fast rate. Thermal issues raised by high heat flux cause IC's performance and reliability problems. To solve these thermal management problems, the conventional cooling methods of IC devices were reached their thermal limit. As a result, alternative cooling methods such as liquid heat pipe, thermoelectric cooler, thermal Si via and etc. are currently emerging. In this paper microchannel liquid cooling system with TSV was investigated. The effects of 2 coolants (DI water and ethylene glycol 70 wt%) and 3 metal bumps (Ag, Cu, Cr/Au/Cu) on cooling performance were studied, and the total heat flux of various coolant and bump cases were compared. Surface temperature of liquid cooling system was measured by infrared microscopy, and liquid flowing through microchannel was observed by fluorescence microscope. In the case of ethylene glycol 70 wt% at $200^{\circ}C$ heating temperature, the total heat flux was $2.42W/cm^2$ and most of total heat flux was from liquid cooling effect.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.30 no.4
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• pp.93-101
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• 2012

Despite the fact that the importance of islands and oceans is increasingly being emphasized as they are recognized as alternative spaces for the future, some islands that have not been designated as cultural assets have lost their natural and cultural landscapes to development projects and other plans for turning islands into tourist resources, and are still in the process of being destroyed. Unlike old perceptions of islands, islands, in the minds of people living in the modern age, have become places for taking a quiet rest or enjoying and appreciating the undamaged beauty of nature itself. Keeping up with the trend of people increasingly visiting the islands these days, it is high time to prepare plans for the promotion, preservation management, and usages of islands based on researches of islands with excellent natural landscapes and through the designation of these islands as cultural properties. As the first step of studying island landscape resources as resources of cultural assets, the current study includes literature reviews and field investigations of Gwanmaedo and Yeongsando, two islands that have been selected as prestigious villages and are part of the Dadohaehaesang National Park. Based on these preliminary investigations, landscape resources showing distinctive natural landscapes and cultural sceneries were selected and analyzed in detail, thus presented for their value as resources of Scenic site and future research.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.4
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• pp.367-377
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• 2021

This study examined the relationship between social support and the subjective well-being of the elderly living in urban areas. The study subjects were 382 elderly people aged 65 or older living in D metropolitan city. The survey was conducted through a personal interview by investigators who visited the study subjects using a structured questionnaire from May 1 to June 30, 2019. As a result, the subjective well-being of the study subjects differed significantly depending on various variables in the sociodemographic, health condition and, health-related behavior characteristics. The subjective well-being according to social support was significantly lower for the groups with lower social support. The correlation of subjective well-being and social support showed a significant positive correlation. Logistic regression showed that the risk of lower subjective well-being increased significantly in the group (Q1), where the total score of social support was very high (Q4). The above results suggest that the subjective well-being of the elderly living in urban areas was not only related to various variables in sociodemographic, health condition, and health-related behavior characteristics but also has significant relationships for social support. Therefore, it is necessary to develop detailed social support practices to improve the subjective well-being.

• Journal of Food Hygiene and Safety
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• v.33 no.6
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• pp.460-465
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• 2018

Deep sea water is deeper than 200 m in depth and maintains cool temperatures. It is clean seawater not contaminated by E. coli and other general bacteria. Because deep sea water is a recyclable resource with high industrial value, activities for commercial use are vigorously developing. We investigated safety, quality characteristics, and mineral contents of prototype products using deep sea water as a substitute for a curing agent and compared it with existing commercially processed products. This study examined the potential of deep sea water as an alternative to curing agent solution. As a result, safety and quality characteristics of processed meat products with deep sea water were not different from commercially processed meat products, but mineral contents were higher in processed meat products with deep sea water. Deep sea water could be widely used as purity salt and purity minerals that can replace chemical substances such as chemical salts. A new, active food market using deep sea water will emerge in the near future.

• Journal of the Microelectronics and Packaging Society
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• v.26 no.1
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• pp.29-33
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• 2019

With shrinking form factor and improving performance of electronic packages, high input/output (I/O) density is considered as an important factor. Fan out wafer-level packaging (FO-WLP) has been paid great attention as an alternative. However, FO-WLP is vulnerable to warpage during its manufacturing process. Minimizing warpage is essential for controlling production yield, and in turn, package reliability. While many studies investigated the effect of process and design parameters on warpage using finite element analysis, they did not take uncertainty into consideration. As parameters, including material properties, chip positions, have uncertainty from the point of manufacturing view, the uncertainty should be considered to reduce the gap between the results from the field and the finite element analysis. This paper focuses on the effect of uncertainty of Young's modulus of chip on fan-out wafer level packaging warpage using finite element analysis. It is assumed that Young's modulus of each chip follows the normal distribution. Simulation results show that the uncertainty of Young's modulus affects the maximum von Mises stress. As a result, it is necessary to control the uncertainty of Young's modulus of silicon chip since the maximum von Mises stress is a parameter related to the package reliability.

• Journal of Science Education
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• v.45 no.1
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• pp.1-10
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• 2021

In this study, we analyzed the relationship between the physical science domain of TIMSS 2019 and the Korean science curriculum. Twelve subjects are presented in the physical science domain of the TIMSS 2019 4th grade evaluation framework. Research group consisting of elementary and middle school teachers and science education experts, a total of 12, participated to analyze in which grade these subjects were included in the Korea 2009 revised and 2015 revised science curriculum. As a results of analyzing whether the achievement standards of the TIMSS 2019 evaluation framework and Korean science curriculum are consistent, the subjects pertinent to chemistry like 'chemical changes in everyday life,' 'heat transfer,' and 'electricity and simple electrical circuits' appeared not covered at all until the 4th grade curriculum in Korea. Given that the TIMSS 2019 evaluation framework is an international achievement standard, we are proposing to improve the Korean curriculum as follows: first, for the development of the next science curriculum, there is a need for science curriculum organized from the 1st grade of elementary school to connect the content and scope of chemistry in elementary, middle, and high schools as a whole including the Nuri curriculum. Second, as an alternative to the problem of suitability of learning volume and level of learning, it is possible to think of a method to readjust the grade of dealing with related concepts by lowering the difficulty or simplifying the concept. Third, it is necessary to discuss about introducing essential concepts and standard terms into Korea science curriculum according to international trends.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.3
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• pp.603-610
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• 2021

The purpose of this study was to develop a Youth Future Career Program for adolescents and to look into the effects of the program on the future efficacy. Through the program, adolescents would predict the future, explore alternative futures to solve future problems, find the shape of the future society they want and desire. In addition, they will discover or create future jobs. In this study, the Youth Future Career Program was developed into four modules: Future Understanding, Future Participation, Future-self, and Future Management. Ninety-three students in K University's Gifted Education Center participated in the Future Career Program (62 males and 31 females, 62 middle school students, and 31 high school students). The students responded to 14 questions about the future efficacy of the Youth before and after the program. Statistically significant differences were observed in 8 out of 14 questions (p<.05). In particular, the abilities of the participants were improved as follows: to apply newly learned things to society, to evaluate the current problems, to develop critical thinking to solve the problem, and to communicate with members of society.

• The Journal of the Convergence on Culture Technology
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• v.8 no.1
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• pp.483-497
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• 2022

Recently, due to COVID-19, non-face-to-face online lectures are being held all over the world. In higher education in the post-corona era, distance learning has become the main teaching and learning method. At this time, Metaverse is being proposed as a new alternative. Metaverse has basic elements such as avatars, 3D space, and activities accompanied by interaction, which can be seen as a difference compared to existing VR (Virtual Reality) contents. This study designed and built an educational metaverse platform that can be applied to actual lectures by reflecting the three elements of the metaverse.In addition, we implemented a cross-device-platform that supports various devices such as HMDs, smartphones, tablets, and PCs by reflecting user requirements through usability tests such as middle school, high school, college students, and parents, so that anyone can easily participate in Metaverse lectures. Currently, the metaverse platform is being developed and serviced in various ways, but there are hardly any services designed for education. Just as services such as Zoom, the existing video conferencing solution, were used for non-face-to-face education, some functions of the currently serviced metaverse are utilized for education and used in the form of a one-time event. The educational metaverse platform developed through this study is expected to be a reference in constructing the metaverse for education in the future.

• Journal of the Korean Institute of Landscape Architecture
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• v.51 no.6
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• pp.12-32
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• 2023

Nowadays, the increasing number of religious travelers seeking inner healing has led to the popularity of Buddhist 'temple stays', Protestant and Catholic 'retreats' as alternative vacations. However, unlike Buddhist temples, which are inculturated, Christian retreat centers follow the formula of general recreational facilities and lack an overall framework due to relying on sponsorship. This study attempts to design appropriate outdoor environments for a retreat by reflecting 'theological aesthetics' based on the process of 'Spiritual Exercises', the main method of retreat. First, as the Spiritual Exercises are often described as an 'inner pilgrimage', the images and theological aesthetics experienced in prayer themes were examined. Next, the characteristics of the spaces required for the facility were analyzed, and the composition of religious spaces was proposed. Also the landscape resources of the site were investigated, and the retreatants' behavior to derive spatial preferences was analyzed. Overall, outdoor spaces were planned to induce a shift in consciousness and broaden the spectrum of the retreatants' experience through a physical environment consistent with the mechanism of prayer. This study aimed to implement theological aesthetics by selecting a retreat center with high potential for landscape resources. As a result, it was possible to reveal the 'poetic landscape' to effectively evoke images during 'contemplative prayer', and to support religious experience. The significance of this study lied in deriving various design vocabularies for outdoor spaces of religious facilities.

• Journal of the Korean Geosynthetics Society
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• v.23 no.1
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• pp.39-47
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• 2024

In this study, physical property tests and standard consolidation tests were conducted on the marine clay of Busan New Port and North Port, the middle and lower reaches of the Nakdong River including Gimhae and Yangsan, and Ulsan regions. The moisture content, a property unrelated to sample disturbance with small individual test errors, was used for regression analysis with the compression index, virgin compression index, consolidation coefficient, expansion index, and secondary compression index, among others. Subsequently, the correlation and accuracy were evaluated. Upon analyzing the correlation between the moisture content, void ratio, and liquid limit commonly used physical properties for calculating compression indexes, it was confirmed that the liquid limit had the lowest correlation. Through a linear regression analysis of the consolidation constants using the current moisture content in the natural state, a high correlation was demonstrated. Relationship equations were then presented to determine settlement and settlement time. This study suggests that moisture content can be utilized as an alternative for evaluating and calculating consolidation constants when examining ground settlement in sedimentary clays distributed in the Busan and Gyeongnam regions.