• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.11
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• pp.861-869
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• 2020

A dynamo set for a high-power induction motor drive is expensive and needs a long time to manufacture. Therefore, the development of a simulator that functions as the induction motor and load equipment is required. A load simulator of an inverter for a high-power three-phase induction motor consists of a reactor and three-phase PWM inverter. Therefore, it cannot simulate the dynamic characteristics of an induction motor and functions only as a load. In this paper, a real-time simulator is proposed to simulate a model of an induction motor and the load characteristics based on an LCL filter and three-phase PWM rectifier for a three-phase induction motor. The currents of a PWM inverter that simulate the stator currents of the motor are controlled by the inductor currents and capacitor voltages of the LCL filter. The capacitor voltages of the LCL filter simulate the induced voltages in the stator windings by the rotating rotor fluxes of the motor, and the capacitor voltages are controlled by the inductor currents and a PWM rectifier. The rotor currents, the stator and rotor flux linkages, the electromagnetic torque, the slip frequency, and the rotor speed are derived from the inverter currents and the motor parameters. The electrical and mechanical model characteristics and the operation of vector control were verified by MATLAB/Simulink simulation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.8
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• pp.370-378
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• 2020

The Construction Operations Building Information Exchange (COBie) collects and documents a large amount of information from different paths in one place during design and construction projects. This documented information is readily available as a means of continuously transferring data to the facility management systems used by building engineers. In this process, the COBie Worksheet, an open standard form, is used to input the information by simplifying the list required by the user. As a result, COBie was developed to improve dramatically how relevant information is obtained and updated to support operations, maintenance, and asset management at the design and construction stages. On the other hand, to use COBie, a great deal of manual work is required for information linkage and quality inspection with heterogeneous data models. These issues become obstacles to COBie-based facility management system development. This study analyzed the COBie information system and defined the framework for simpler operating maintenance information from BIM (Building Information Modeling). Moreover, the rules for facility management information submission, quality inspection, role definition of framework components, and information linkage were derived. COBie DB schema and support data linkages could be generated effectively based on the proposed framework in prototype development.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.5
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• pp.93-98
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• 2017

The fixing behaviors of raw silk yarns treated with melamine and formaldehyde at a molar ratio of 1:3 for trimethylolmelamine were investigated. Sericin was fixed during the fixing process, but a part of sericin I was removed simultaneously by hot water. The weight losses by fixing and the degumming losses by degumming greatly decreased with increasing concentrations of melamine and formaldehyde. The silk yarns fixed with 0.011 M melamine and 0.033M formaldehyde were significantly degummed due to the insufficient fixation of sericin and the alkaline hydrolysis of sericin by sodium carbonate during the degumming process. On the other hand, the silk yarns fixed with 0.055M melamine and 0.165M formaldehyde were degummed slightly (the degumming losses of 3-8%) due to the strong fixation of sericin, which might result from the many cross-linkages between the sericin I molecules, which were formed by trimethylolmelamine. Those fixed with the fixing solution containing 15% owf softener showed the lowest weight and degumming losses because under the condition of 15% owf softener, the cation of the softener can effectively form ionic bonds with the negatively charged side chain of aspartic acid in sericin. In addition, van der Waals' forces may be also formed between the hydrophobic tail of the softener and the hydrophobic region of sericin, which may help inhibit the removal of sericin I.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.3
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• pp.545-555
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• 2020

The purpose of this study is to derive the linkage between urban regeneration and district unit planning, in order to supplement the limitations of the spread of the effects of individual urban regeneration projects. To this end, institutional changes and previous studies with theoretical backgrounds were reviewed, the urban regeneration strategic plan and district unit plan cases in the spatial scope of Jeju Island were analyzed, and a unified administrative procedure to strengthen linkages was proposed. In addition, when selecting priorities for active regions, we reviewed how to use the indicators of involvement of residents, which enabled the project to be performed smoothly by grasping the participation of residents and the elements of complaints. Also a hypothetical target site was set up and suggested how to establish a district unit plan by type. Depending on the circumstances and environment of the site, the use of the land use plan and the regulation and mitigation of the district unit plan may be appropriately used to expect the inhabitants to expand their participation and revitalization. This study suggests ways to revitalize decayed areas beyond systematic urban planning in connection with systematic plans, to improve administrative procedures, and to promote bottom-up projects.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.12
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• pp.523-531
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• 2018

The purpose of this paper is to derive priorities and implications for the organic resource conservation policy in the livestock sector. We conducted a survey on the importance-performance of the organic waste resource reclamation of livestock sector using a 5-point Likert scale. The importance average for the resource recycling of livestock organic waste was 3.63 and the average of performance was 3.04. As a result of the IPA on livestock manure recycling measures, it is necessary to improve feed quality, establish a local recycling system, increase demand for compost and liquid, enhance customer linkages, and develop cost reduction technologies. It requires intensive support for promoting the spread of odor reduction technologies and integrated management of biomass. It is necessary to introduce mid- and long-term measures such as the revival of feed in tariff, promote by-product feeding, establish solid fuel process management standards, create hygiene safety standards, develop eco-beads and promotion of feed conversion. It is required to strengthen support for the development of odor reduction technologies and prepare consultative organizations among related departments, develop eco-friendly solid fuel technology, and support policies for renewable energy certification.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.18 no.4
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• pp.149-163
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• 2023

The policy of promoting innovation clusters aims to enhance the competitiveness of industries by strengthening the linkages between industry sectors and research sectors in specific regions. In Korea, after the concept of innovation clusters was introduced by the OECD in 1997, Korean government actively pursued policies based on this concept in the fields of industry, region, and science and technology. Previous policies and research on the activation of innovation clusters have tended to focus on the exchange and collaboration among members. However, this study focused on enhancing the competitiveness of industries and regions, in other words, strengthening the competitiveness of companies, which is the fundamental reason for fostering innovative clusters. Accordingly, this study aimed to analyze the impact of factors activating innovation clusters on the business performance of SMEs located in the Daedeok Innopolis. To achieve this, based on the essential concept of innovation clusters such as industrial agglomeration factors, networking factors, innovation generation factors, the study derived factors for activating innovation clusters and verified hypotheses using the survey results of 175 companies. Among the factors activating innovation clusters, industrial agglomeration and innovation generation were found to have a positive impact on the business performance of companies. However, networking factors were analyzed to have no significant influence on the business performance of companies. This study differentiates itself by addressing the factors for activating innovation clusters through empirical analysis, unlike previous case-based studies. Furthermore, considering the difference between intuitive judgments on networking factors in innovation clusters and their actual impact on business performance, the study raised the practical significance of conducting a comprehensive examination from various perspectives, such as the socially and culturally embedded structures in the region, the characteristics of specialized industries, and the needs of cluster members, to develop more effective policies for innovation clusters.

• Applied Chemistry for Engineering
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• v.9 no.2
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• pp.185-192
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• 1998

Four kinds of polyamicacids(PAAs) were prepared by the condensation reaction of four diamines with different linkages, 3,3'-diaminodiphenyl sulfone(3,3'-$DDSO_2$), 4,4'-diaminodiphenyl sulfone(4,4'-$DDSO_2$), 4,4'-methylene dianiline(4,4'-MDA) and 4,4'-oxydianiline(4,4'-ODA), and dianhydride, 3,3', 4,4'-benzophenone tetracarboxylic dianhydride (BTDA) using the solvent, dimethylacetamide(DMAc). These four PAAs were blended with poly[2,2-(m-phenylene)-5,5'-bibenzimidazole](PBI) from the solution blending. Then called as Blend-I, II, III, and IV, respectively. Cast films or precipitated powders of the PBI/PAA blends were cured at a higher temperature than expected Tg to transform into PBI/PIs blends. Miscibility, specific intermolecular interaction for miscibility and their relative strength as a function of polyimide chemical structure with different four diamines in the PBI/PI systems were investigated. Four blends used in this study were all miscible, and the specific intermolecular interactions existing in these blends was thought to be the hydrogen bonding between the N-H of PBI and the C=O of PIs. The hydrogen bonding in the blends were shown to be stronger in the Blend-III and Blend-IV than Blend-I and II. It is speculated that the differences of hydrogen bonding strength of PBI/PI blends are dependent upon chemical structures of PIs, that is, PIs consisting of $SO_2$ group have a weaker hydrogen bonding strength than those of O or $CH_2$ group because the former has a larger spacer than the latter.

• The Journal of the Korea Contents Association
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• v.13 no.5
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• pp.517-526
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• 2013

Lifelong education promotion business to be the first to promote lifelong education promotion accountable to the governor of the city, the Lifelong Education Act Amendment (2007.12) emphasis on the research area 6 Lifelong Education and Lifelong Education Institute is established if analyzes what Gyeongsangnam-do lifetime policy implications for the promotion of education and implications are derived(through AHP). The results were as follows: occupational skill enhancement education (0.335) as the priority section. The development of life education policy (0.238) is the primary work process that must be initiated for the Gyeongnam life education promotion policy appropriate for the region's situation. This was followed by the development and distribution of life education program (0.148), construction of a connective system between life education organizations within the province (0.139) Raised the need to promote lifelong Education strategies, five core strategic industry linkages through regional industrial policy to keep pace with the flow of business for the Advancement of Education for the development and activation of Gyeongsangnam-do in a lifetime.

• Journal of Applied Biological Chemistry
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• v.54 no.1
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• pp.1-6
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• 2011

${\gamma}$-PGA(poly-${\gamma}$-glutamic acid) is an unusual anionic polypeptide that is made of D- and L-glutamic acid units connected by amide linkages between ${\alpha}$-amino and ${\gamma}$-carboxylic acid groups. ${\gamma}$-PGA has been isolated from many kinds of organisms. Many Bacillus strains produce ${\gamma}$-PGA as a capsular material of an extracellular viscous material. It is safe for eating as a viscosity element of fermented soybean products such as Chungkookjang and Natto. It is biodegradable, edible and nontoxic toward humans and the environment and its molecular weight varies from ten thousand to several hundred thousand depending on the kinds of strains used. Therefore, potential applications of ${\gamma}$-PGA and its derivatives have been of interest in the past few years in a broad range of industrial fields such as food, cosmetics, medicine, water-treatment, etc. In this study, a bacterium, Bacillus subtilis GS-2 isolated from the Korean traditional seasoning food, Chungkookjang could produce a large amount of ${\gamma}$-PGA with high productivity and had a simple nutrient requirement. Based on carbon utilization pattern and partial 16S rRNA sequence analysis, the GS-2 strain was identified as B. subtilis. The determination of purified ${\gamma}$-PGA was confirmed with thin layer chromatography (TLC), high performance liquid chromatography (HPLC), fourier transform infrared (FT-IR) spectra, and $^1H$-nuclear magnetic resonance ($^1H$-NMR) spectroscopy.

• Journal of Korea Technology Innovation Society
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• v.18 no.3
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• pp.387-415
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• 2015

In this study, we have proposed an estimation model of domestic market size using the linking between standard statistical classification systems, and reviewed the practical applicability of the model. The results of the mining and manufacturing survey of Statistics Korea conducted on the basis of KSIC (Korea Standard Industrial Classification) and Korea trade statistics based on HS (The Harmonized Commodity Description and Coding System; Harmonized System) classification were linked for the model by using the correspondence tables provided by Statistics Korea and United Nations Statistics Division. The most serious problem to adopt the integrated KSIC-ISIC-HS correspondence table for the estimation of domestic market size is the complex multiple linkages among KSIC and HS codes. In this study, we have suggested the method to divide the amount of trade corresponding to the HS codes linked to more than two ISIC codes based on the ratio of shipments corresponding to the ISIC codes as the weight. Then, it is possible to analyze the domestic market size of 125 ISIC codes in the manufacturing industry and to forecast the market size in the near future by using the model. Although the model has some limitations such as the difficulty in analysis on more subdivided items than ISIC items, the impossibility of the analysis on items in industries except for manufacturing, errors in the shipment due to some missing data, this study has significance in the sense that it provided the analysis method of domestic market size by using the most objective, reliable and sustainably useful data.