• Clean Technology
• /
• v.29 no.4
• /
• pp.305-312
• /
• 2023

Due to the strengthening of environmental requirements, aging denitrification facilities need to improve their performance. The present study aims to suggest the possibility of improving performance using computational analysis techniques. This involved modifying both the geometric design and the operating conditions, including the flow path shape of the equipment such as the inlet guide vane and the curved diffusing part, and the flow control of the ammonia injection nozzle. The conditions presented in this study were compared with existing operating conditions in terms of the flow uniformity, the NH₃/NO molar ratio of the mixed gas flowing into the catalyst layer, and the total pressure drop of the facility. The flow field applied in the computational analysis ranged from the outlet of the economizer in the combustion furnace to the inlet of the air preheater, the full domain of the denitrification facility. The performances were derived by solving the flow fields using ANSYS-Fluent and the injection amount of ammonia was adjusted for each nozzle using Design Xplorer. Compared to the denitrification performances of the equipment currently in operation, the conditions proposed in this study showed an improvement in the flow uniformity and NH₃/NO composition ratio by 45.1% and 8.7%, respectively, but the total pressure drop increased by 1.24%.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.29 no.6
• /
• pp.672-680
• /
• 2023

Weight is a critical factor in the ship design process given that it has a substantial impact on the hydrodynamic performance of ships. Typically, ships are optimally designed for specific conditions with a fixed draft and displacement. However, in reality, weight and draft can vary within a certain range owing to operational activities, such as fuel consumption, ballast adjustments, and loading conditions . Therefore, we investigated how resistance changes under three different loading conditions, namely overload, design-load, and lightship, for small craft, using both model experiments and numerical simulations. Additionally, we examined the sensitivity of weight changes to resistance to enhance the performance of ships, ultimately reducing power requirements in support of the International Maritime Organization's (IMO) goal of reducing CO2 emissions by 50% by 2050. We found that weight changes have a more significant impact at low Froude Numbers. Operating under overload conditions, which correspond to a 5% increase in draft and an 11.1% increase in displacement, can lead to a relatively substantial increase in total resistance, up to 15.97% and 14.31% in towing tests and CFD simulations, respectively.

• Journal of the Institute of Convergence Signal Processing
• /
• v.24 no.2
• /
• pp.126-133
• /
• 2023

In this study, electromyography was obtained in the six muscle areas that move the joints of the two legs, and by analyzing it, an exercise robot system capable of gait rehabilitation was proposed in consideration of the individual's muscle state. Through this, the system was constructed to prevent the effect of exercise from decreasing because the patient's will was not reflected when walking exercise was simply provided automatically. As a result of the evaluation of the developed system, it was confirmed that the pedestrian rehabilitation robot system manufactured through this study had performance suitable for the design requirements, and it was also confirmed that the usability evaluation was comprehensively satisfactory. The results of this study are thought to be of great help to patients who are having difficulty in gait rehabilitation, and are believed to be helpful in the development of electromyography signal-based gait robot systems.

• The Journal of KAIRB
• /
• v.5 no.2
• /
• pp.43-50
• /
• 2023

Purpose: Due to the stringency of regulations related to clinical research, researchers face various requirements in the Institutional Review Board (IRB) review process. Specifically, they encounter time constraints and administrative burdens. In order to cultivate a more favorable review culture and establish a robust research environment, it is necessary to analyze researchers' perceptions of the IRB review. Therefore, this study aims to assess researchers' overall experiences with the IRB and identify researchers' educational needs and demands for research-related policies. Methods: A semistructured questionnaire with 34 items was developed and refined in consultation with advisors from IRB and Human Research Protection Program (HRPP). The questionnaire was distributed via an online survey to researchers with experience in IRB review. The survey covered general characteristics, satisfaction with the IRB review process (rated on a 10-point scale), experiences with IRB review, HRPP policy demands. Results: The study's descriptive statistics revealed a moderate satisfaction level (average rating, 6.75 out of 10) with the IRB review. Researchers from clinical medicine and other disciplines showed similar satisfaction scores of 6.65 and 6.87, respectively. However, respondents with over 5 years of research experience expressed higher satisfaction (mean score, 7.03) compared to those with less experience (mean score, 6.57). Institutional support was emphasized for improving the IRB review process. Certain training topics generated higher demands for addressing frequently raised IRB issues among minor discipline researchers compared to clinical medicine (p=0.017). Conclusion: We conducted an analysis of researchers' perceptions regarding the IRB as well as their demands concerning educational and HRPP policies. It is imperative to address the pinpointed areas for enhancement and integrate a range of perspectives in order to effectively cultivate a robust research ethics culture and ensure comprehensive participant protection.

• Journal of Intelligence and Information Systems
• /
• v.29 no.4
• /
• pp.375-393
• /
• 2023

The demand for Less than Container Load (LCL) has been on the rise due to the growing need for various small-scale production items and the expansion of the e-commerce market. Consequently, more companies in the International Freight Forwarder are now handling LCL. Given the variety in cargo sizes and the diverse interests of stakeholders, there's a growing need for a container loading algorithm that optimizes space efficiency. However, due to the nature of the current situation in which a cargo loading plan is established in advance and delivered to the Container Freight Station (CFS), there is a limitation that variables that can be identified at industrial sites cannot be reflected in the loading plan. Therefore, this study proposes a container loading methodology that makes it easy to modify the loading plan at industrial sites. By allowing the characteristics of cargo and the status of the container to be considered, the requirements of the industrial site were reflected, and the three-dimensional space was manipulated into a two-dimensional planar layer to establish a loading plan to reduce time complexity. Through the methodology presented in this study, it is possible to increase the consistency of the quality of the container loading methodology and contribute to the automation of the loading plan.

• Journal of the Korean Crystal Growth and Crystal Technology
• /
• v.33 no.6
• /
• pp.234-243
• /
• 2023

Zinc crystals of ZnO and SiO₂ in glaze raw materials, developed according to composition and firing requirements, are preferred because of their high decorative properties. However, most zinc crystal glazes have a high firing temperature and a narrow firing temperature range, making it difficult to use them as commercial glazes in ceramics. Therefore, in this study, it was expected that the firing temperature of a typical zinc crystal glaze could be lowered to below 1270℃ by using the eutectic effect through mixing frit, the main raw material used in manufacturing zinc crystal glaze. As a result, not only was the formation temperature of zinc crystals lower in the mixed frit glaze, but also the firing temperature range was widened to 1230~1270℃, making it possible to develop a glaze that produces crystals stably. The firing temperature was lowered to 1230~1250℃ and the holding temperature during cooling was lowered to about 950℃, resulting in the development of an economically effective glaze. When using a combination of frit, it has been shown that the holding temperature during cooling affects the recrystallization of zinc crystals depending on the composition of the glaze, and the crystal structure can be adjusted at this time. Additionally, the amount and shape of crystals can be controlled by using a nucleating agent.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
• /
• v.18 no.5
• /
• pp.159-174
• /
• 2023

In this paper, we proposed a methodology to effectively determine the selection and prioritization of new business and innovation projects using AI technology. AI technology is a technology that can upgrade the business of companies in various industries and increase the added value of the entire industry. However, there are various constraints and difficulties in the decision-making process of selecting and implementing AI projects in the enterprise. In this paper, we propose a new methodology for prioritizing AI projects using Morphology, AHP, and TOPSIS. The proposed methodology helps prioritize AI projects by simultaneously considering the technical feasibility of AI technology and real-world user requirements. In this study, we applied the proposal methodology to a real enterprise that wanted to prioritize multiple AI projects in the HR field and evaluated the results. The results confirm the practical applicability of the methodology and suggest ways to use it to help companies make decisions about AI projects. The significance of the methodology proposed in this study is that it is a framework for prioritizing multiple AI projects considered by a company in the most reasonable way by considering both business and technical factors at the same time.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
• /
• v.17 no.1
• /
• pp.79-87
• /
• 2022

Recently, as the awareness of the necessity of entrepreneurship education has spread in secondary education, the competency of educators in the field of education has become more important. This study tried to derive the priority of education needs by exploring the competency of educators to practice entrepreneurship education and the result from analysis of the difference in importance and performance. For conducting the analysis, this study conceptualized entrepreneurship education competency based on the TPACK (Technological Pedagogical Content Knowledge) model and developed a questionnaires to measure those competencies. Using TPACK and developed questionnaires, a survey was conducted on 217 secondary school teachers who were interested in entrepreneurship education, and derived the difference between importance-level and current-level was analyzed with a t-test. As a result of the study, for all sub-factors of TPACK, the mean of importance-level was higher than the mean of current-level, indicating that educational prescription was required. Also, as a result of analysis of Borich's requirements and The Locus for Focus Model, it was found that the factor with the highest priority in education was CK(Content Knowledge). Based on the results of study, implications for strengthening competencies for entrepreneurship educators were derived.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
• /
• v.17 no.1
• /
• pp.177-189
• /
• 2022

This study proposes policy recommendations for the Korea New Exchange ("KONEX"), which is a financial platform for SMEs and startups that relied on indirect and policy financing in the past. SMEs and venture firms with limited human and physical listing resources can grow through market incubation, and venture capitalists expect an early exit or return on investment. However, the lack of liquidity and sluggish trading volume have weakened the function of the market. Despite prior policy efforts, the number of newly listed companies has decreased while listing demand for KOSDAQ and K-OTC has increased. This study aims to suggest short- and long-term improvements in regulations and throughout the KONEX firms' listing life cycle. First, the minimum deposit requirement on individual investors should be abolished to increase the number of investors. Second, information disclosure should be conducted by firms so that the nominated advisor can focus on discovering and supporting new listed companies. Third, in order to increase trading volume, the 5% dispersion rule should be changed to 25% dispersion incentive principle. Fourth, a new track without profit condition in expedited transfer listing should be introduced because the KOSDAQ relaxes the profit realization requirements for listing. Lastly, transfer listing without additional review for firms that fulfill ownership dispersion, information disclosure, and investor protection will strengthen the incubating role of the KONEX.

• Journal of Aerospace System Engineering
• /
• v.18 no.1
• /
• pp.11-20
• /
• 2024

In the recent era of NewSpace, unlike high-reliability satellites of the past, low-reliability satellites are being developed and mass-produced at a lower cost to launch constellations satellites. To achieve cost-effective cluster satellite development, satellite users and developers need to assess the feasibility of maintaining mission performance over the expected lifespan when cluster satellites are launched. Plans for replacements due to random failures should also be established to maintain performance. This study proposed a method for assessing system reliability and availability to maintain mission performance and establish replacement strategies for Earth observation constellation satellites. In this study, a constellation reliability and availability model considering mission performance required for a satellite constellation, situations of satellite backup, and additional ground backups was established. The reliability model was structured based on the concept of a k-out-of-n system and the availability model used a Markov chain model. Based on the proposed reliability model, the minimum number of satellites required to meet mission requirements was defined and satellites needed in orbit during the required mission period to satisfy mission reliability were calculated. This research also analyzed the number of spare satellites in orbit and on the ground required to meet the desired availability during required service period through availability analysis.