• Journal of Korea Foundry Society
• /
• v.43 no.6
• /
• pp.271-278
• /
• 2023

In the present study, A356 melt degassing experiments were conducted under various impeller rotation speed and inert gas flow rate conditions to determine changes in the melt temperature, composition and density during a degassing treatment. The melt temperature was found to decrease gradually as the degassing time increased, but a clear correlation between the impeller rotation speed or inert gas flow rate and the melt heat loss could not be confirmed. Regardless of the impeller rotation speed or inert gas flow rate, the Mg and Ti contents in the A356 melt scarcely changed, even after degassing for more than 10 minutes, while Sr contents decreased at the maximum degassing rate of 70 ppm. From a quantitative analysis of the degassing rate under each experimental condition based on the hydrogen concentration in the melt derived from the melt density and the degassing model equation, the inert gas flow rate was found to affect the degassing rate rather than the impeller rotation speed under the degassing operation condition employed in the present study.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
• /
• v.17 no.2
• /
• pp.141-151
• /
• 2022

This exploratory study was conducted to derive the components of digital entrepreneurship by targeting the experts related to Information and Communication Technology (ICT). Through the review of previous studies and Delphi analysis, the major components of digital entrepreneurship were derived into the 'digital entrepreneurial orientation area' and the 'digital technology competency area'. The components of digital entrepreneurship are innovativeness, proactiveness, risk-taking, desire for achievement, ability to identify digital business opportunities, digital technology utilization capability, digital operation process establishment capability, digital technology development capability, digital technology acceptance, information exchange, and cooperation network establishment, digital-based customer acquisition and management was presented. The importance and execution of success factors were measured through IPA analysis. The first quadrant(keep up the good work) includes proactiveness, ability to identify digital business opportunities, and ability to establish digital business processes. The second quadrant(concentrate here) includes innovativeness, digital technology development capability, and digital technology acceptance. The third quadrant(low priority) includes risk-taking, desire for achievement, digital technology utilization capacity, and digital-based customer acquisition and management. The fourth quadrant(possible overkill) includes information exchange and cooperation network establishment. This study is meaningful in that it presents the concept and components of digital entrepreneurship for digital entrepreneurs that can be applied in Korea.

• Journal of Navigation and Port Research
• /
• v.47 no.6
• /
• pp.394-400
• /
• 2023

Unlike advancements on land, the maritime industry has been slow to embrace new technologies, primarily due to user apprehension toward unproven innovations in the development process. The existing paradigm of technology development, marked by expert-oriented and laboratory-centric test environments, often leads to a stagnation of progress at the research stage, as the applicability of the technology remains uncertain. This study departed from the conventional research system and introduced a novel methodology known as a "living lab." This approach aimed to ensure applicability by actively involving field-oriented users throughout the entire lifecycle of technology development, encompassing planning, development, verification, and evaluation. The presentation of a plan for the construction and operation of such a living lab in this study is expected to contribute to establishing an efficient experimentation system for ships that can reflect user opinions in the future and to secure technology applicability in the maritime field.

• Tunnel and Underground Space
• /
• v.34 no.3
• /
• pp.231-247
• /
• 2024

In the field of high-level radioactive waste disposal targeting deep rock environments, hydraulic characteristic information serves as the most important key factor in selecting relevant disposal sites, detailed design of disposal facilities, derivation of optimal construction plans, and safety evaluation during operation. Since various rock types are mixed and distributed in a small area in Korea, it is important to conduct preliminary work to analyze the hydrogeological characteristics of rock aquifers for various rock types and compile the resulting data into a database. In this paper, we obtained hydraulic conductivity data, which is the most representative field hydraulic characteristic of a high-depth volcanic bedrock aquifer, and also analyzed and evaluated the field data. To acquire field data, we used a high-performance hydraulic testing system developed in-house and applied standardized test methods and investigation procedures. In the process of hydraulic characteristic data analysis, hydraulic conductivity values were obtained for each depth, and the pattern of groundwater flow through permeable rock joints located in the test section was also evaluated. It is expected that the series of data acquisition methods, procedures, and analysis results proposed in this report can be used to build a database of hydraulic characteristics data for high-depth rock aquifers in Korea. In addition, it is expected that it will play a role in improving technical know-how to be applied to research on hydraulic characteristic according to various bedrock types in the future.

• The Journal of the Convergence on Culture Technology
• /
• v.10 no.2
• /
• pp.273-278
• /
• 2024

The purpose of this study is to examine the limitations of university operating system changes as a result of the policy changes and outcomes of the university lifelong education system support project by project period, and based on this, to propose a development plan to support the university's adult learning system. In this study, we sought to investigate changes in the higher education environment and changes in lifelong education in universities through analysis of literature and various data. The changing times of technological innovation and changes in knowledge require continuous learning even after school education, and the need for re-education and improved education is increasing. Therefore, the Ministry of Education and the National Institute for Lifelong Education have been actively carrying out support projects for lifelong learning-centered universities since 2008 to provide adult learners with opportunities to study. This project is centered around universities and the local community, and is promoting various types of changes in educational operation, such as reforming the university's academic system to be adult-friendly and operating night or weekend classes in order to provide educational opportunities for adult learners. Now, universities must play a role as a hub of regional lifelong education for the coexistence of the region and university, and as a key institution responsible for the contemporary tasks of sustainable development and coexistence between the university and the community.

• Industry Promotion Research
• /
• v.9 no.1
• /
• pp.39-45
• /
• 2024

Dangerous tasks that occur every day at industrial site manufacturing plants, which have recently been making rapid changes, were classified by type, and the effect of mobile circuit television (CCTV) on safety accidents among daily safety management methods was analyzed. The subject of the study is about 3,000 workers who manage the infrastructure facility sector to supply utilities such as gas, water, and electricity to the display manufacturing process located in Asan City, and the study was conducted based on the daily dangerous work from 2019 to 2022, and during this study period, many construction works such as new investment and expansion of construction and manufacturing processes were occurring at the site. As a result, the rate of safety accidents and exposure to risks are expanding, and most of the safety accidents occurred because the sectors that did not follow the basics and the safety measures on the site were not implemented. In this paper, it was confirmed that there is an accident reduction effect according to the relationship between the dangerous work classified according to the work importance and the mobile CCTV shooting rate. Considering the characteristics of the manufacturing plant site, it can be used to play the role of basic data for preventing safety accidents based on the expansion of the introduction of a new safety management culture in the future.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.44 no.1
• /
• pp.85-93
• /
• 2024

The monitoring of environmental information (e.g. noise, dust, vibration, temperature, humidity) is crucial to the safe and sustainable operation of a construction site. However, commercial sensors exhibit certain drawbacks when applied on-site. First, the installation cost is prohibitively high. Second, these sensors have been engineered without considering the rugged and harsh conditions of a construction site, resulting in error-prone sensing. Third, construction sites are compelled to allocate additional resources in terms of manpower, expenses, and physical spaces to accommodate individual sensors. This research developed an integrated sensing module to measure the environmental information in construction site. The sensing module slashes the installation cost to 3.3%, is robust enough to harsh and outdoor sites, and consolidates multiple sensors into a single unit. The sensing module also supports GPS, LTE, and real-time sensing. The evaluation showed remarkable results including 97.5% accuracy and 99.9% precision in noise measurement, an 89.7% accuracy in dust measurement, and a 93.5% reliability in data transmission. This research empowers the collection of substantial volumes and high-quality environmental data from construction sites, providing invaluable support to decision-making process. These encompass objective regulatory compliance checking, simulations of environmental data dispersion, and the development of environmental mitigation strategies.

• The Journal of the Convergence on Culture Technology
• /
• v.10 no.1
• /
• pp.289-295
• /
• 2024

This study analyzes the correlation between the accracy of rifle and the result of engagement. And estimates the improvement cost of the rifle accordingly. For this experiment, an engagement class simulation model(AWAM: Army Weapon Effectiveness Analysis Model) was used. We also selected the rifle, which is a portable weapon for the experiment. Prior to this experiment, we conducted a reliability test(VV&A: Verification, Validation and Accreditation) on the model. The VV&A process is mainly done during the development of the DM&S model, which is also necessary for the operation of the M&S. We confirmed the need for VV&A during the experiment and obtained reliable experimental results using the corrected values. In the Accuracy Experiment we found that the 20% improvement is the most effective. And we were able to estimate the cost of acquiring a rifle with a 20% higher accuracy. The cost was estimated by simple regression analysis based on the price of the current rifle. Through this study, we could know the impact of the accuracy of rifle on the experimental results and estimate the cost of improved rifle.

• Journal of Korean Library and Information Science Society
• /
• v.55 no.1
• /
• pp.27-45
• /
• 2024

We conducted a survey in collaboration with the Chungcheongbuk-do Office of Education to assess the current status of collections in public libraries affiliated with the Office of Education. The objective of this survey was to identify the current challenges and determine when these libraries are expected to reach a state of collection saturation. Libraries under the jurisdiction of the Chungcheongbuk-do Office of Education are currently facing significant challenges due to severe collection saturation. This underscores the pressing need for the systematic expansion and operation of a collaborative preservation library for a swift response. In the future, it appears that the focus during the transfer process will primarily be on transferring collection-oriented materials. Given the difficulty in providing preservation facilities at individual library levels, materials with preservation value, such as rare books and specialized resources, will need to be transferred to the collaborative preservation library. Additionally, the development of policies and regulations related to material preservation seems necessary. Furthermore, when transferring materials to the collaborative preservation library in the future, it appears that criteria for material transfer will be needed, particularly concerning issues such as a decrease in usage rates for less frequently accessed materials. Subsequent research should consider conducting a survey on the collection saturation status of public libraries under local governments in order to assess the overall need for collection expansion in all public libraries within Chungcheongbuk-do.

• Journal of the Korean earth science society
• /
• v.45 no.1
• /
• pp.48-71
• /
• 2024

Typhoons are representative oceanic and atmospheric phenomena that cause interactions within the Earth's system with diverse influences. In recent decades, the typhoons have tended to strengthen due to rapidly changing climate. The 2022 revised science curriculum emphasizes the importance of teaching-learning activities using advanced science and technology to cultivate digital literacy as a citizen of the future society. Therefore, it is necessary to solve the temporal and spatial limitations of textbook illustrations and to develop effective instructional materials using global-scale big data covered in the field of earth science. In this study, according to the procedure of the PDIE (Preparation, Development, Implementation, Evaluation) model, the inquiry activity data was developed to visualize the track of the typhoon using the image data of GK-2A. In the preparatory stage, the 2015 and 2022 revised curriculum and the contents of the inquiry activities of the current textbooks were analyzed. In the development stage, inquiry activities were organized into a series of processes that can collect, process, visualize, and analyze observational data, and a GUI (Graphic User Interface)-based visualization program that can derive results with a simple operation was created. In the implementation and evaluation stage, classes were conducted with students, and classes using code and GUI programs were conducted respectively to compare the characteristics of each activity and confirm its applicability in the school field. The class materials presented in this study enable exploratory activities using actual observation data without professional programming knowledge which is expected to contribute to students' understanding and digital literacy in the field of earth science.