• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.20 no.10
• /
• pp.33-39
• /
• 2019

The improvement of emissions, fuel economy, and combustion noise is a primary target in the development of heavy-duty diesel engines. Multiple injection has been introduced as one of the most promising strategies for this goal. In this research, various multiple injection methods were applied to achieve the optimal strategy in terms of emissions, fuel economy, and combustion noise. In the case of one pilot injection, the smoke emission deteriorated, while the NOx emission was reduced. In the case of 2 pilot injections, the NOx and smoke emissions were reduced by 73% and 84%, respectively. In this case, the combustion noise was analyzed with the maximum pressure-rise rate, and the fuel economy was evaluated with the help of the indicated specific fuel consumption. A 15%:15% 2-pilot injection strategy accomplished improvements of 32.9% for NOx, 60.4% for smoke, 1.95% for fuel consumption, and 19.4% for combustion noise compared to the case of single injection. Based on the data, an optimal injection strategy will be developed for a greater operating range in future work.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
• /
• v.16 no.2
• /
• pp.95-108
• /
• 2021

Technology innovation activities are very important for companies to secure technological competitiveness and continue to grow. Korea operates a certification system at the national level to promote corporate innovation activities, and strives to enhance SMEs' global technological competitiveness. Among these, the representative system related to technological innovation is the New Excellent Technology (NET) certification. NET is certified through a strict three-stage screening process, and is operated for the purpose of commercialization of new technology, technology trading, and promotion of early market entry by companies. Acquiring NET certification means that the company has a certain level of technological competitiveness. Therefore, this study attempted to conduct an empirical analysis on which technology innovation activities of companies affect the success of R&D projects and improvement of management performance, centering on NET certification system. To verify this, technology strategy, technology planning, systematic R&D process, internal cooperation, and external cooperation activities were set as major variables. As a result of the empirical analysis, it was confirmed that all variables set in this study individually contributed to the success of the R&D project and improvement of management performance. However, when looking at a comprehensive level that considers all variables, it was analyzed that systematic R&D process management and cooperation activities with external organizations have a statistically significant effect on R&D project success, and technology strategy establishment and technology planning activities, which are the initial stages of R&D, have a statistically significant effect on management performance. This study was conducted on innovation-oriented SMEs that have established and operated corporate R&D centers and are actively conducting R&D activities, and multiple regression analysis was used as an analysis method.

• Journal of Service Research and Studies
• /
• v.12 no.3
• /
• pp.158-175
• /
• 2022

This study discusses mass unemployment and job insecurity due to the 4th industrial revolution and technological progress. In particular, the construction automation service method can contribute to increasing work productivity, preventing on-site safety accidents, and enhancing the competitiveness of the construction industry according to rapid development and convergence between technologies. However, there is great concern that the position of workers will decrease and the income distribution will deteriorate. Therefore, this study is necessary to alleviate the anxiety of the labor market and to find a direction for the government and all walks of life to ponder. To carry out this study, in-depth interviews were conducted with two experts currently engaged in the construction field, and through analysis, we intend to derive meaning and identify current trends, identify necessary improvement measures and institutional areas and suggest research directions. As a result of the analysis, it is possible to suggest a response strategy in a total of three themes: purpose, implication, and strategy. Based on this, there are response strategies in four areas: (1) industrial site response, (2) worker response, (3) education, and (4) training response, and government and corporate response. Through this study, it is necessary to revitalize economic and sociological discussions in the future so that the improvement in productivity and efficiency of society as a whole due to technological innovation of construction automation services does not lead to social problems such as an increase in the unemployment rate and a decrease in jobs in the labor market.

• 대한공업교육학회지
• /
• v.33 no.2
• /
• pp.1-25
• /
• 2008

In this study, theory of school consulting for founding the development strategy of industrial high school was explored, consulting model and performing technique model was suggested, case of consulting of industrial high school performed by the model and performing technique suggested. Up to now, research field of school consulting was instruction and supervision consulting mostly, there was not much school management consulting. In this paper, a school consulting model for industrial high school was developed, which was five step such as entry, diagnosis, action planning, action, and termination. A case of consulting for C technical high school applied by the consulting model suggested was analyzed, it will be used any other consulting project of industrial high school. According to the 5 step school consulting model, analysis of the present state of C technical high school, survey research, SWOT analysis, Issue Tree, school assesment were performed. In order to set up a development strategy for C technical high school, a table of problem and improvement based on issue tree was made, and then a Pay-Off Matrix was made out. Finally, a development plan of short and mid- and long-term for C technical high school was constructed.

• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.46 no.9
• /
• pp.25-32
• /
• 2009

Recently, research for Network-on-chip(NoC) is progressing. However, due to the increase of system complexity and demand on high performance, conventional copper-based electrical interconnect would be faced with the design limitation of performance, power, and bandwidth. As an alternative to these problems, combined use of Electrical Interconnects(EIs) and Optical Interconnects(OIs) has been introduced. In this paper we propose efficient routing optimization strategy and hybrid switch architecture, which use OIs for critical path and EIs for non-critical path. The proposed method shows up to 25% performance improvement and 38% power reduction.

• Journal of Information Technology Applications and Management
• /
• v.26 no.3
• /
• pp.99-120
• /
• 2019

The purpose of this study is to provide information necessary for establishing a new strategy for customer service improvement by deriving factors affecting user satisfaction and continuous use intention of mobile app service user characteristics, system characteristics, and social characteristics. The results of this study are summarized as follows. First, reliability, innovation, familiarity, convenience, and self-efficacy among the characteristics of mobile app are analyzed as factors that have the greatest influence on user's perceived usefulness. Second, convenience, mobility, and visibility are some of the characteristics of mobile app service. Third, identity, security, and expectation agreement among mobile app service characteristics are analyzed as negative factors that do not affect users' perceived usefulness. Fourth, interactivity, familiarity, and self-efficacy among the characteristics of mobile app service were analyzed as positive factors that have the greatest effect on user's perceived ease of use. Fifth, reliability, mobility, visibility, and convenience among mobile app service characteristics are analyzed as factors that have some positive effects on perceived ease of use of app users. Sixth, identity, innovation, and security among the characteristics of mobile app service are negatively influenced by mobile app users' perceived ease of use. Seventh, the perceived usefulness of mobile app users is analyzed as a factor that has a very positive effect on user satisfaction. Eighth, the perceived ease of use of mobile app users is analyzed as a factor affecting perceived usefulness positively. Ninth, the perceived ease and expectation of mobile app users are positively influenced on user satisfaction. The tenth, the perceived usefulness of the mobile app users was analyzed as a factor having a very positive influence on the persistent intention to use. For the eleventh, the perceived ease of use of mobile app users was analyzed as a factor having a positive effect on the persistent intention to use. The twelfth, mobile app user satisfaction was analyzed as a factor having a very positive effect on the persistent intention to use.

• Neonatal Medicine
• /
• v.28 no.3
• /
• pp.108-115
• /
• 2021

Purpose: Magnetic resonance imaging (MRI) is a useful tool for evaluating brain injury and maturation in preterm infants and often requires sedation to acquire images of sufficient quality. Infant sedation is often associated with adverse events, despite extreme precautions. In this study, the swaddling technique was investigated as an alternative non-pharmacological strategy to obtain brain MRIs of sufficient quality. Methods: We applied the feed and swaddle technique during routine brain MRI as a quality improvement project and compared its morbidity with that of sedation in a historic age-matched group. Seventy-nine very low birth weight infants in the neonatal intensive care unit of Ajou University Hospital (Suwon, Korea) were enrolled. Thirty-two (40.5%) infants were in the feed and swaddling group, and 47 (59.5%) were in the sedation group. Results: The morbidity associated with the cardiopulmonary system (swaddling group vs. sedation group: 53.13% [n=17] vs. 63.83% [n=30], P=0.723) and central nervous system (40.63% [n=13] vs. 29.79% [n=14], P=0.217) were not significantly different between groups. The MRI failure rate was not significantly different (swaddling group vs. sedation group: 12.5% [n=4] vs. 4.3% [n=2], P=0.174). The MRI scanning time was longer in the swaddling group than in the sedation group (76.5±20.3 minutes vs. 61.5±13.6 minutes, P=0.001). Cardiopulmonary adverse events were significantly less common in the swaddling group than in the sedation group (3.13% [n=1] vs. 34.04% [n=16], P=0.002). Conclusion: The success rate of MRI was comparable between the swaddling technique and sedation. Furthermore, despite the drawback of prolonged scan time, cardiopulmonary adverse events are fewer with swaddling than with sedative agents. Therefore, swaddling can be an alternative to sedation or anesthesia when performing neonatal MRI scans.

• Hwankyungkyoyuk
• /
• v.16 no.1
• /
• pp.34-47
• /
• 2003

The purpose of this study is to analyze the program development process of a nonformal environmental education(EE) program in detail. For the purpose, following research questions were answered in "the Nature School in the Forest" program in Eco-Club 1) What is the program development process? 2) What is the role of staffs, program developers, in the program development process? What are the meanings of their pedagogical approach? 3) With the findings of this study, how is the researcher able to develop ground theory for community-based nonformal EE, and to promote theoretical discussion for field improvement? The data were mainly gathered through participation observation and unstructured interview. And the data were analyzed by qualitative techniques such as clustering, factoring, noting pattern and themes, seeing plausibility, making metaphors, and building logical chain of evidence. The following conclusion comes out of the findings of this study. "The Nature School in the Forest" program is a educational device which the community-based NGO chose as a strategy to change individuals and community with its ideological purpose. And the program development process was the contiuous group decision-making process among staffs and volunteers. Consequently "the Nature School in the Forest" program is a circulated process of the voluntary activists training and their participation in program operation.

• Journal of The Korean Society of Agricultural Engineers
• /
• v.65 no.2
• /
• pp.13-20
• /
• 2023

In the past, the Ministry of Agriculture, Food, and Rural Affairs (MAFRA) conducted research into and production of agricultural statistics. As a result of organizational changes, these responsibilities were transferred to Statistics Korea in 1998 and 2008. So, the MAFRA managed data without a formal system for managing data and statistical information. The demand for a foundation to improve the usefulness of agri-food statistics has recently increased due to the necessity for basic data representing the realities of rural and agricultural areas. This is especially true for field-oriented agricultural administration. This study aims to propose a strategy for the systematically integrated administration of dispersed data and statistical information. It served as the foundation for the integrated management of distributed administrative and statistical data.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.18 no.7
• /
• pp.2027-2046
• /
• 2024

Reconfigurable Intelligent Surface (RIS) is an innovative technique to precisely control the phase of incident signals with the help of low-cost passive reflective elements. It shows excellent potential in the sixth generation of mobile communication systems, which not only extends wireless coverage but also boosts channel capacity. Considering that multipath propagation and a high number of antennas are involved in RIS in assisted mega multiple-input multiple-output (MIMO) systems, it suffers from severe channel fading and multipath effects, which in turn lead to signal instability and degradation of transmission performance. To overcome this obstacle, this essay suggests an improved gradient optimization algorithm to dynamically and optimally adjust the phase of the reflective elements to counteract channel fading and multipath effects as a strategy. In order to overcome the optimization problem of falling into local minima, this paper proposes an adaptive learning rate algorithm based on Adagrad improvement, which searches for the global optimal solution more efficiently and improves the robustness of the optimization algorithm. The suggested technique helps to enhance the estimate of channel efficiency of RIS-assisted large MIMO systems, according to simulation results.