• Nuclear Engineering and Technology
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• v.55 no.12
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• pp.4357-4366
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• 2023

MARS-KS, a domestic regulatory confirmatory code of Republic of Korea, had been developed by integrating RELAP5/MOD2 and COBRA-TF. The integration of COBRA-TF allowed to extend the capability of MARS-KS, limited to one-dimensional analysis, to multi-dimensional analysis. The use of COBRA-TF was mainly focused on subchannel analyses for simulating multi-dimensional behavior within the reactor core. However, this feature has been remained as a legacy without ongoing maintenance. Meanwhile, MARS-KS also includes its own multidimensional component, namely MULTID, which is also feasible to simulate three-dimensional convection and diffusion. The MULTID is capable of modeling the turbulent diffusion using simple mixing length model. The implementation of the turbulent mixing is of importance for analyzing the reactor core where a disturbing cross-sectional structure of rod bundle makes the flow perturbation and corresponding mixing stronger. In addition, the presence of this turbulent behavior allows the secondary transports with net mass exchange between subchannels. However, a series of assessments performed in previous studies revealed that the turbulence model of the MULTID could not simulate the aforementioned effective mixing occurred in the subchannel-scale problems. This is obvious consequence since the physical models of the MULTID neglect the effect of mass transport and thereby, it cannot model the void drift effect and resulting phasic distribution within a bundle. Thus, in this study, the turbulence mixing model of the MULTID has been improved by means of the inter-channel mixing model, widely utilized in subchannel analysis, in order to extend the application of the MULTID to small-scale problems. A series of assessments has been performed against rod bundle experiments, namely GE 3X3 and PSBT, to evaluate the performance of the introduced mixing model. The assessment results revealed that the application of the inter-channel mixing model allowed to enhance the prediction of the MULTID in subchannel scale problems. In addition, it was indicated that the code could not predict appropriate phasic distribution in the rod bundle without the model. Considering that the proper prediction of the phasic distribution is important when considering pin-based and/or assembly-based expressions of the reactor core, the results of this study clearly indicate that the inter-channel mixing model is required for analyzing the rod bundle, appropriately.

• Journal of Electrochemical Science and Technology
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• v.15 no.4
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• pp.476-483
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• 2024

Lithium-ion (Li-ion) batteries are essential to modern society, but pose safety risks because of thermal runaway and ignition. This study explores the use of hybrid aqueous electrolytes to enhance the safety and performance of Li-ion batteries, focusing on the solid-electrolyte interface (SEI) formed on lithium titanate (Li₄Ti₅O₁₂; LTO) electrodes. We employed high-resolution transmission electron microscopy (HRTEM) and density functional theory (DFT) calculations to analyze the microstructure and stability of the SEI layer. Further, we prepared LTO and LiMn₂O₄ (LMO) electrodes, assembled full cells with hybrid aqueous electrolytes, and carried out electrochemical testing. The HRTEM analysis revealed the epitaxial growth of a LiF SEI layer on the LTO electrode, which has a coherent lattice structure that enhances electrochemical stability. The DFT calculations confirmed the energetic favorability of the LiF-LTO interface, indicating strong adhesion and potential for epitaxial growth. The full cell demonstrated excellent discharge performance, showing a notable improvement in coulombic efficiency after the initial cycle and sustained capacity over 100 cycles. Notably, the formation of a dense, crystalline LiF SEI layer on the LTO electrode is crucial for preventing continuous side reactions and maintaining mechanical stability during cycling. The experimental results, supported by the DFT results, highlight the importance of the orientational relationship between the SEI and the electrode in improving battery performance. The integration of experimental techniques and computational simulations has led to the development of an LTO/LMO full cell with enhanced discharge capabilities and stability. This study provides insights into the growth mechanisms of the SEI layer and its impact on battery performance, demonstrating the potential of hybrid aqueous electrolytes in advancing lithium-ion battery technology. The findings affirm the viability of this approach for optimizing next-generation Li-ion batteries, which can promote the development of safer and more reliable energy storage solutions.

• Journal of agriculture & life science
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• v.53 no.4
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• pp.93-101
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• 2019

Dog (Canis lupus familiaris) is a member of genius Canis that forms part of the wolf-like canids, and it has been evolved to diverse domestic breeds since 100 thousand years ago. Practical dog breed identification has been emerged to important part of pet industry such as genealogical certificates. From 11 dog breeds, 226 dogs and 23K SNP genotypes, we selected minimal SNPs of breed identification using machine learning algorithms including multiclass classification and feature selection. With 100 times of random choice of 70% data for training and 30% testing, we evaluated 9 classifiers' accuracies and 2 methods of feature selection. Linear SVM and PCA weighted feature selection showed the best accuracy of classification. Finally, we selected SNP markers and it could identify 11 breeds with approximately 90% accuracy, when having 40 SNP. This marker set is expected to be useful for dog breed and disease management by integration with disease markers.

• Journal of the Microelectronics and Packaging Society
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• v.31 no.3
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• pp.1-9
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• 2024

This paper addresses the significance of Cu/Polymer Hybrid Bonding technology in the advancement of semiconductor packaging. As the demands of the AI era increase, the semiconductor industry is exploring heterogeneous integration packaging technologies to achieve high I/O counts, low power consumption, efficient heat dissipation, multifunctionality, and miniaturization. The conventional Cu/SiO₂ Hybrid Bonding structure faces limitations such as achieving compatibility with CMP processes to attain surface roughness below 1nm and the occurrence of bonding defects due to particles. However, Cu/Polymer Hybrid Bonding technology, utilizing polymers, is gaining attention as a promising alternative to overcome these challenges. This study focuses on the deposition, patterning, and material properties of polymers essential for Cu/Polymer Hybrid Bonding, highlighting the advantages and potential applications of this technology compared to existing methods. Specifically, the use of polymers with low glass transition temperatures (Tg) is discussed for their benefits in low-temperature bonding processes and improved mechanical properties due to their high coefficients of thermal expansion. Furthermore, the study explores surface property modifications of polymers and the enhancement of bonding mechanisms through plasma treatment. This research emphasizes that Cu/Polymer Hybrid Bonding technology can serve as a critical breakthrough in developing high-performance, low-power semiconductor devices within the industry.

• Journal of Internet of Things and Convergence
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• v.10 no.6
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• pp.135-149
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• 2024

The purpose of this study is to study ways to eliminate social exclusion through the use of digital devices by people with disabilities in the digital age. The research results are as follows. First, all social exclusion factors had an effect on quality of life. Second, except for health, family, social participation, finance, culture, and employment in the social exclusion factors had an effect on digital device usage attitude. Third, except for health, family, social participation, finance, culture, and employment in the social exclusion factors had an effect on digital device usage self-efficacy. Fourth, digital device usage attitude had a partial mediating effect in the relationship between family, social participation, finance, culture, and employment factors of social exclusion and quality of life. Fifth, digital device usage self-efficacy had a partial mediating effect in the relationship between family, social participation, finance, culture, and employment factors of social exclusion and quality of life. Sixth, differences by gender were found in the family factor of social exclusion. Seventh, differences by age were found in social exclusion, quality of life, digital device usage attitude, and digital device usage self-efficacy. Eighth, differences by disability type were shown in social exclusion, quality of life, digital device usage attitude, and digital device usage self-efficacy. Through this study, we presented effective ways to use digital devices. We hope that these ways will contribute to eliminating social exclusion and improving quality of life for people with disabilities, and to achieving sustainable social integration while increasing digital inclusion for people with disabilities.

• Journal of Animal Science and Technology
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• v.44 no.6
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• pp.793-800
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• 2002

The characteristics of carcass and meat yields of fattening pigs by production steps were investigated with Landrace (LL, n=41), Yorkshire (YY, n=33), and Duroc (DD, n=30), $F_1$ (LY, n=25), the Crossbred of LYD (n=48). Duroc had more weight loss in carcasses weight than that of the other breed(p<0.05). Yorkshire and $F_1$ had higher production weight in retail cut than that of the other pure or crossbred. Carcass from Landrace and $F_1$ were significantly longer in length than the other breed(p<0.05). $F_1$ produced wider carcass than the other breed. Carcass thickness at aitch bone was higher for $F_1$ and Crossbred than the other breed(p<0.05). Landrace, Yorkshire and $F_1$ produced more loin and tenderloin in weight than the other breed (p<0.05). Yorkshire and $F_1$ produced more picnic shoulder when compared to the other breed. The hind legs produced from Yorkshire and $F_1$ were higher in weight and the fore legs produced from the Crossbred were higher in weight. Duroc produced the lowest weight of belly among the breeds. The acceptance level of loin were extremely low for all breed. Landrace had the highest acceptance level for tenderloin. Yorkshire had the highest acceptance level for picnic shoulder and ham when evaluated by export standard of Japan. In conclusion, The introduction of pure breed and establishment of mating steps are necessary to produce highly accepted pork with high acceptance in carcass and meat yields.

• Journal of Internet Computing and Services
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• v.16 no.2
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• pp.57-66
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• 2015

Considerable research efforts are being directed towards analyzing unstructured data such as text files and log files using commercial and noncommercial analytical tools. In particular, researchers are trying to extract meaningful knowledge through text mining in not only business but also many other areas such as politics, economics, and cultural studies. For instance, several studies have examined national pending issues by analyzing large volumes of text on various social issues. However, it is difficult to provide successful information services that can identify R&D documents on specific national pending issues. While users may specify certain keywords relating to national pending issues, they usually fail to retrieve appropriate R&D information primarily due to discrepancies between these terms and the corresponding terms actually used in the R&D documents. Thus, we need an intermediate logic to overcome these discrepancies, also to identify and package appropriate R&D information on specific national pending issues. To address this requirement, three methodologies are proposed in this study-a hybrid methodology for extracting and integrating keywords pertaining to national pending issues, a methodology for packaging R&D information that corresponds to national pending issues, and a methodology for constructing an associative issue network based on relevant R&D information. Data analysis techniques such as text mining, social network analysis, and association rules mining are utilized for establishing these methodologies. As the experiment result, the keyword enhancement rate by the proposed integration methodology reveals to be about 42.8%. For the second objective, three key analyses were conducted and a number of association rules between national pending issue keywords and R&D keywords were derived. The experiment regarding to the third objective, which is issue clustering based on R&D keywords is still in progress and expected to give tangible results in the future.

• Journal of the Korean Institute of Landscape Architecture
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• v.50 no.5
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• pp.40-53
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• 2022

This study carried out to provide the methodology and basic status material of using Korean national statistics needed to find the actual state of the landscape architecture industry. The landscape architecture industry was classified into 'Design', 'Construction Management', 'construction', 'Maintenance & Management', 'Materials', 'Research', 'Education', and 'Administration' areas. In each field, business types were systemized and associated in accordance with Korean standard industrial classification and legislations pertinent to construction. Among them, the business types directly defined in the construction related legislations under the Ministry of Land, Infrastructure and Transport were focused on, and the establishment, association, integration, distribution, duplication, and omission of national statistics were analyzed. As a result, the business types of statistical analysis were selected. In order for commonality of statistical items and minimized error of interpretation, semantic analysis was conducted. Finally, the number of registered business types, the number of workers, and sales were selected. Based on them, the analysis framework applicable to fundamental analysis and evaluation of the actual state of the industry was proposed. Actual national statical data were applied for analysis and evaluation. In 2019, the number of registered business types related to the landscape architecture industry was 12,160, the number of workers by business type was 106,296, and the sales by business type were 8,308.5 billion KRW. The number of registered business types and the number of workers had been on the rise from 2017, whereas the sales had been on the decrease. It is required to come up with a plan for industrial development. This study was conducted with the national statistics established by multiple public institutions, so that there are limitations in securing consistency and reliability. Therefore, it is necessary to establish systematic and consistent national statistics in accordance with 「Landscaping Promotion Act」. In the future, it will planned to research application and development plans of national statistics according to subjects including park and green.

• Journal of Korean Home Economics Education Association
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• v.26 no.1
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• pp.1-16
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• 2014

The purpose of this research is to develop a theme-based integrated teaching/learning plan in clothing, food, and housing in home economics and to apply the developed process in classes for evaluation in order to identify the suitability in schools. The theme-based integrated teaching/learning plan developed on the basis of textbooks consist four sub-themes; choosing($1^{st}$ and $2^{nd)$ lessons), using($3^{rd}$ lesson), processing ($4^{th}$ lesson), and alternatives($5^{th}$ and $6^{th}$ lessons) under the main theme of 'green family life'. The results from 20 individual and group activities showed that the students actively solved the problems when the presented cases were related to their own lives or experiences. The opportunity to implement green life through activities motivated students' willingness to proceed in real life. However, it is vital to assist integrated thinking through various examples before beginning due to students with difficulties connecting the issue from one area to the other during the problem-focused activity. The students' ability to solve the activity workbook had been improved as the lessons continued. From the survey questions on the theme-based integrated lessons, all items associated with integration of clothing, foods, and housing were positively responded. Also, questions regarding general understanding, suitability and satisfaction on the teaching/learning process were marked positive. The conclusion could be that the integrated theme related to clothing, food, and housing in our life would be appropriate for green family life. The theme-based integrated teaching/learning plan is effective in understanding the occurrence of green family life in relation with clothing, food, and housing, identifying the practical ideas implementing green life in those areas, and improving the integrated ability to solve the green life related problems. However, this research has its weakness in generalizing the results due to its limited survey respondents and post-evaluation being the only assessment conducted.

• The Korean Journal of Archival Studies
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• no.5
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• pp.39-85
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• 2002

This paper is aimed at proposing the policies for managing archives in the process of promoting Electronic Government System. Although there have been many studies of electronic government project and plans for its establishment, this research examines the electronic government system and its problems on the basis of archival science. What I acquired in this paper is as follows. The development of information technology needs great changes ranging from the nation to the individuals. It becomes common that the use of computerized program for business purposes, computerization of information materials and the effective way of search use of electronic documents. Therefore, more and more countries all over the world have been seeking to promote 'Electronic Government', which applies the fruits of the development in information technology to administration process. Recently, Korea has been rapidly entered into the 'Electronic Government' system being against the traditional way of administration. In electronic government system, the 'Life Cycle' of public records will be computerized. Therefore, it is important to change and develop along with the government's policies for 'electronic government project' in the archival management system. This means that the archival management system which have put emphasis on the textual records should be converted to electronic records system. In other words, the records management in electronic government system requires not the transfer and preservation of the records but the consistent management system including the whole process of creating, appraising, arranging, preserving and using the records. So, the systematic management of electronic records plays an important role in realization of electronic government, but it is a subject to be realized by electronic government at the same time. However, the government have overlooked the importance of archival management for long time, especially the importance of electronic records management system. First of all, this research attempts to infer limits and problems through the theoretical considerations of the existing studies for electronic government and to clear up the relations between electronic government and archival management. Based on this, I'll seek to progress the study through reviewing the present condition of archival management in the process of promoting electronic government and suggesting the policies for enhancing the successful electronic government and the construction of scientific archival management system. Since early 1990, many countries in the world have been making every effort to concrete 'Electronic Government'. Using the examples in other nations, it is not difficult to recognize that the embodiment of electronic government is closely connected with the archival management policies. Korea have completed legal and institutional equipments including the new establishment of "Electronic Government Law" to realize electronic government. Also, Korea has been promoting electronic government with the Ministry of Government Administration and Home Affairs and Government Computer Center as a leaders. Though managing records, especially the management of electronic records is essential in electronic government system, we haven't yet discussed this section in Korea. This is disapproved by the fact the Government Archives and Records Service has played little role in promoting electronic government project. There are two problems relating this environment. First, present system can't meet the consistent 'Life Cycle' ranging from the creation to the preservation of electronic records. Second, the 'Life Cycle' of electronic records is divided into two parts and managed separately by GCC and GARS. The life of records is not end with the process raged from creation to distribution. On the other hand, the records are approved their value only whole procedures. Therefore, GARS should play a deading role in designing and establishing the archival management system. The answer to these problems, is as follows. First, we have to complete the electronic records management system through introducing ERMS not EDMS. This means that we should not change and develop towards ERMS simply with supplementing the current electronic records management system. I confirm that it is important and proper to establish ERMS system from the very beginning of the process of promoting electronic government. Second, I suggest the developmental integration of GARS and GCC. At present, the divided operations of GCC and GARS, the former is in charge of the management center for electronic business and the latter is the hub institution of managing nation's records and archives result in many obstacles in establishing electronic government system and accomplishing the duties of systematic archival management. Therefore, I conclude that the expansive movement towards 'National Archives' through the integration among the related agencies will make a great contribution to the realization of electronic government and the establishment of archival management system. In addition to this, it will be of much help to constitute and operate the 'Task Force' regarding the management of electronic records with the two institution as the central figures.