• Journal of the Korea Society of Computer and Information
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• v.23 no.11
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• pp.193-201
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• 2018

In this paper, we extracted relevant patent data and conducted statistical analysis to understand the technical development trend related to Wireless Power Transfer (WPT) for Light Rail Transit (LRT). Recently, with the development of WPT technologies, the Light Rail Transit (LRT) industry is concentrating on applying WPT to the power supply system of trains because of their advantages compared wired counterpart, such as low maintenance cost and high stability. This technology is divided into three areas: wireless feeding and collecting technology, high-frequency power converter technology and orbital and infrastructure technology. From each specific area, key words in patent document were extracted by TF-IDF method and analyzed by social network. In the keyword network, core word of each specific technology were extracted according to their degree centrality. Then, the multi-word phrases were also built to represent the concept of core technologies. Finally, based on the analysis results, the development strategies for each specifics technical area of WPT in LRT filed will be provided.

• Nuclear Engineering and Technology
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• v.51 no.2
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• pp.369-376
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• 2019

A complete solution for a soluble-boron-free (SBF) small modular reactor (SMR) is pursued with a new burnable absorber concept, namely centrally-shielded burnable absorber (CSBA). Neutronic flexibility of the CSBA design has been discussed with fuel assembly (FA) analyses. Major design parameters and goals of the SBF SMR are discussed in view of the reactor core design and three CSBA designs are introduced to achieve both a very low burnup reactivity swing (BRS) and minimal residual reactivity of the CSBA. It is demonstrated that the core achieves a long cycle length (~37 months) and high burnup (~30 GWd/tU), while the BRS is only about 1100 pcm and the radial power distribution is rather flat. This research also introduces a supplementary reactivity control mechanism using stainless steel as mechanical shim (MS) rod to obtain the criticality during normal operation. A further analysis is performed to investigate the local power peaking of the CSBA-loaded FA at MS-rodded condition. Moreover, a simple $B_4C$-based control rod arrangement is proposed to assure a sufficient shutdown margin even at the cold-zero-power condition. All calculations in this neutronic-thermal hydraulic coupled investigation of the 3D SBF SMR core are completed by a two-step Monte Carlo-diffusion hybrid methodology.

• Journal of Korea Society of Digital Industry and Information Management
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• v.18 no.3
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• pp.83-95
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• 2022

A technology can be newly formed through technological convergence achieved by the intersection of two or more technological fields. As the complexity of technology development increases, related interest is increasing. Researches have been carried out on the concept, related indicators and analysis of technology convergence including method of social networks. This paper intends to suggest an analysis method of technology convergence using social networks based on the company's possessing technologies. According to the similarity of technologies among companies, a social network was constructed and the technology convergence was analyzed using k-core, a social network subgroup method. Using the result of k-core, base and element technologies for convergence was identified with their relations. Using the suggested method, technology convergence was analyzed on real technology data of defense-industry companies. When the minimum technology similarity is 0, the overall technology convergence relations between technology elements can be identified. In the scope of data in this paper, technologies of defense S/W, aircraft structure and structural materials are identified as important base technology for convergence.

• The Journal of the Korea Contents Association
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• v.15 no.8
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• pp.209-217
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• 2015

Main purpose of this study is to investigate the effect of the self core evaluation of local public officials on the customer-oriented public service provision. Structural Equation Model was applied to analyze the relationship between self core evaluation and customer oriented public service attitude. From theoretic point, establishing the relationship between psychological concept(self core evaluation) and attitude is contribution to existing literature in this area. Positive structural relationships between self core evaluation and customer-oriented attitude was confirmed from empirical analysis. While variable job engagement took intermediating role between self core evaluation and customer-oriented attitude. The result implies that organizational psychological approach might be a more effective policy measure to improve citizen's satisfaction for public services. For a extended periods, Korean government introduced various institutional arrangements to improve the customer satisfaction for public service. Hoever, the result was not satisfactory. The result of this study suggest psychological approach to improve public service customer satisfaction.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.39 no.6
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• pp.71-78
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• 2002

A method of soft switching in the half bridge converter using a small saturable core is presented. For the soft switching, a small dead time of both switch off is made in a pair of MOSFET switch. The saturable core is of rectangular magnetization characteristics and the core flux swings from the minus to the plus saturation during ON time of the switch. The soft switching is realized in dead time by a resonance between the saturating inductance of the core and the stray capacitance of MOSFET. As an extension of this concept, instead of the saturable core, we propose a new soft switching circuit using a linear inductance and two switches, which is especially suitable for regulating the output and also for high frequency switching. A theoretical principle of soft switching presented here was confirmed by experiments on a half bridge converter of 1.25 KW.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.18 no.11
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• pp.103-108
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• 2019

The cooling rate and the uniformity of mold temperature, in the injection molding process, possess great influences on the productivity and quality of replications. The conformal cooling channel, which is of a uniform spacing from the mold cavity by the metal additive manufacturing process, receives much attention recently. The purpose of this study is to develop a mold core with a curved conformal cooling channel for a pottery-shaped thick-wall cosmetic container through the hybrid method of direct metal tooling (DMT) process. In this study, we design a mold core that contains the curved cooling channel for the container. A method that divides the cavity is proposed and the DMT process is carried out to form the curved cooling channel. The test mold core, with the curved conformal cooling channel, has been fabricated by the proposed method to confirm the feasibility of the design concept. We show that no leakage is observed for the additive manufactured test mold core, and its physical properties demonstrate that it can be sufficiently used as the injection mold core.

• Herbal Formula Science
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• v.32 no.2
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• pp.129-139
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• 2024

Objective : This study aims to investigate core herbs and formulas in Internal Medicine on the Liver system (IML) to enhance the efficiency of teaching IML, Herbalogy, and Formula Science, as well as to increase the integration of these courses. Methods : The study employed the frequency concept, commonly utilized in previous studies, alongside network analysis. Results : This study identified frequently used herbs, herbs with high centrality, frequently combined herbs, and core formulas. The herb with the highest frequency was 'Angelicae Gigantis Radix', while the herb with the highest centrality was 'Citri Unshius Pericarpium', and the most frequent herb combination was 'Zingiberis Rhizoma - Citri Unshius Pericarpium'. The network analysis results revealed a total of 5 herbal combination communities. Conclusion : In this study, we identified core herbs using traditional frequency analysis methods. Additionally, to complement traditional analysis methods, we discovered core herbal combinations, and fundamental herbal prescriptions through network analysis. The results of this study can be utilized as foundational data to enhance the efficiency of education in Internal Medicine on the Liver system (IML), Herbology, and Formula Science courses, as well as to improve coherence and consistency between foundational and clinical subjects.

• Journal of architectural history
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• v.18 no.2
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• pp.85-105
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• 2009

This study set out to compare and analyze the influences Kabbalah, which was Louis I. Kahn's faith as a Jew, on his architecture based on Freud's psychoanalysis that had many exchanges with modernism and contemporary architecture and theories. The specific goals of the study were to shed light to Kahn's presence in contemporary architecture anew and establish the methodology of using psychoanalysis in building new theories of architectural planning. When the theories of psychoanalysis were introduced for comparison and analysis purposes, Kahn tried to differentiate his buildings by placing a function or symbolic central space at the heart of a building even though he did adopt a characteristic of modernism architecture, which was placing a core at the centre of plan, for a while. Such a tendency of his was based on Jung's opinions rather than Freud's and affected by Ecole des Beaux-Art. The analysis results also indicate that he conceived "Served Space & Servant Space," "architecture of connection" and "silence and light" that made up the essence of his architectural theory from the relationships between Ayin-Sof, Kabbalah's absolute god, and Sefiroth. It's also very likely that his often use of triangles and circles in his architecture was affected by the Tree of Sefiroth diagram of Kabbalah. His tendency is well reflected in Salk Institute and Philips Exeter Academy Library, where he placed a laboratory or courtyard at the center where a core was supposed to be, created a corridor or courtyard space between those central spaces and the core, and connected them one another with to perceive the being of Ayin-Sof into an architectural space, which is well proven with Mikveh Israel Synagogue where he directly applied the Tree of Sefiroth diagram. The synagogue also contained a hollow column that served as an important concept in his late architecture. The hollow column was also the result of him applying the concept of Sefiroth of the place where Ayin-Sof Was reduced in Kabbalah.

• The KSFM Journal of Fluid Machinery
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• v.17 no.6
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• pp.109-114
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• 2014

After the Fukushima accident in 2011, it was revealed that nuclear power plant has the vulnerability to SBO accident and its extension situation without sufficient cooling of reactor core resulting core meltdown and radioactive material release even after reactor shutdown. Many safety systems had been developed like PAFS, hybrid SIT, and relocation of RPV and IRWST as a part of steps for the Fukushima accident, however, their applications have limitation in the situation that supply of feedwater into reactor is impossible due to high pressure inside reactor pressure vessel. The concept of hybrid heat pipe with control rod is introduced for breaking through the limitation. Hybrid heat pipe with control rod is the passive decay heat removal system in core, which has the abilities of reactor shutdown as control rod as well as decay heat removal as heat pipe. For evaluating the cooling performance hybrid heat pipe, a commercial CFD code, ANSYS-CFX was used. First, for validating CFD results, numerical results and experimental results with same geometry and fluid conditions were compared to a tube type heat pipe resulting in a resonable agreement between them. After that, wall temperature and thermal resistances of 2 design concepts of hybrid heat pipe were analyzed about various heat inputs. For unit length, hybrid heat pipe with a tube type of $B_4C$ pellet has a decreasing tendency of thermal resistance, on the other hand, hybrid heat pipe with an annular type $B_4C$ pellet has an increasing tendency as heat input increases.

• Journal of Korean Home Economics Education Association
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• v.28 no.2
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• pp.51-59
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• 2016

In this study, we identified the theoretical basis of management and planning of life-cycle, the core concept of resource "Administration and Independence," of Home Economics curriculum according to "Notification of Education Ministry #2015-74." First in relation to "management", we identified the systematic theory, the theoretical basis of traditional home management, and diagnosed how this systematic theory is reflected on 2015' curriculum. As a result, the contents of actual curriculum's middle school contents does not include integrally the life related problems that middle students are facing in real life, and it is hard to be convinced what priority the element of selected contents have of several problems. Next, in case of planning of life-cycle that accentuates the importance of life plan corresponding to career orientation it mentions the contents including very comprehensive area such as value, profession, health as well as developmental task, but the fact leaves to be desired that 2015 curriculum is overlooking the importance of financial planning, the international trend.