• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.22 no.4
• /
• pp.396-402
• /
• 2021

A cross section in RC flexural members must be designed to satisfy flexural strength and ductility requirements simultaneously. In design provisions, ductile behavior is ensured by a sufficient reinforcement ratio or depth of the neutral axis. If the reinforcement ratio is less than the balanced reinforcement ratio, ductile behavior is secured, and this value is theoretically the maximum reinforcement ratio. But for a cross section with less steel, brittle failure can occur regardless of ductile behavior because of unqualifying a cracking moment. Recently, designs with a minimum steel ratio have been increasing along with the use of high-strength material, so in design provisions, a minimum amount of reinforcement is suggested. In the KCI(2012) standard, a minimum amount of reinforcement was suggested in terms of strength of steel and concrete. But in the revised KCI(2017) standard, a minimum amount of reinforcement was suggested by a relationship between the design flexural strength and cracking moment indirectly. This code can reflect the effect of cover thickness, but a material model must be defined. Therefore, the minimum amount of reinforcement in KCI(2012) and KCI(2017) was examined, and a rational review method was studied by parametric analysis.

• The Korean Journal of Archival Studies
• /
• no.58
• /
• pp.31-63
• /
• 2018

The foremost priority for establishing record management of public institutions is strengthening the function and role of the records centers in the institutions and creating the foundation of the organization and personnel for demonstrating professionalism of archivists. However, concept of current records center is not clear and there is no substance of the organization. It also says that once a records manager is deployed, a records center is founded since appointment criteria for archivists is prone to be interpreted subjectively by the institutions. Therefore, it's time for more concrete improvements to resolve these issues. This research analyses some problems found in the system of records centers in the main office and district offices of education focusing on the environment of them. The problems are centers without substance in district offices of education because of the organization structure that all authority has been assembled in the main office, and the reality of records managers who have fallen into records discarders, etc. To solve these problems, this paper proposes changing the appointment criteria for archivists, operating an integrated records center reflecting the intensive working system, and legislating special act on record management of educational institutions.

• Communications of Mathematical Education
• /
• v.33 no.3
• /
• pp.163-180
• /
• 2019

This study introduces a development of calculus contents which makes to understand the main concepts of calculus in a short period of time and to enhance problem solving and computational thinking for complex problems encountered in the real world for college freshmen with diverse backgrounds. As a concrete measure, we developed 'Teaching and Learning' contents and Python-based code for Calculus I and II which was used in actual classroom. In other words, the entire process of teaching and learning, action plan, and evaluation method for calculus class with Python based coding are reported and shared. In anytime and anywhere, our students were able to freely practice and effectively exercise calculus problems. By using the given code, students could gain meaningful understanding of calculus contents and were able to expand their computational thinking skills. In addition, we share a way that it motivated student activities, and evaluated students fairly based on data which they generated, but still instructor's work load is less than before. Therefore, it can be a teaching and learning model for college mathematics which shows a possibility to cover calculus concepts and computational thinking at once in a innovative way for the 21st century.

• Management & Information Systems Review
• /
• v.38 no.1
• /
• pp.63-81
• /
• 2019

In order to overcome the disadvantages of banner ad, pop-up ad, interstitial ad, which are existing web advertisement forms, native ad is actively utilized. Native advertising is considered to be a useful advertising technique in that it can reduce users' rejection and attract attention. However, in recent years, there have been a lot of fake news and fake contents that have turned articles or video contents into advertisements. The purpose of this study is to understand how firms can coordinate and control native advertisements in a rational way. For this analysis, we conducted a survey of 308 social media users using quota sampling method. As a result of the verification, it was found that the more negative the perception of the evaluation of the advertisement, the less the level of persuasion about the advertisement and the negative impact on the website where the advertisement is exposed. In addition, this study examined the influence of the negative stimulus factors on the qualitative performance of the firm. As a result, it was found that source non-expert had the highest effect on skepticism on ad. Also, platform overflow has a direct effect on the evaluation of the website as well as the negative evaluation of the advertisement. Moreover, this study provides concrete implications for the subdivision market by verifying the differences between the paths according to the level of website involvement.

• Industry Promotion Research
• /
• v.4 no.1
• /
• pp.57-66
• /
• 2019

The extant research literature is scant in telling us how organizations actually implement lifelong learning practices and policies. Hence, the purpose of this paper is to describe how lifelong learning is grounded in practice. We do this by introducing a new conceptual framework that was developed on the basis of interviews with a number of leading edge corporations from Canada, the USA, India and Korea. At the heart of our model, and any effective lifelong learning system, is a performance management system. The performance management system allows for an ongoing interaction between managers and employees whereby challenging performance and learning goals are set, and concrete plans are made to achieve them. Those plans involve three types of learning activities. First, employees may be encouraged to engage in formal learning. This could be provided in-house, or the employee may take a leave of absence and return to school. Second, managers may deploy their subordinates to different departments or teams, so that they can take part in new work-based learning opportunities. Finally, employees may be encouraged to learn on their own time. By this we mean learning after organizational hours through firm-sponsored 5 programs, such as e-learning courses. Fueled by the performance management system, we posit that these three learning outlets lead to effective lifelong learning in organizations.

• The Journal of the Convergence on Culture Technology
• /
• v.8 no.5
• /
• pp.515-524
• /
• 2022

The turnout system of the sleeper floating tracks (STEDEF) on urban transit is a Anti-vibration track composed of a wooden sleeper embedded in a concrete bed and a sleeper resilience pad under the sleeper. Therefore, deterioration and changes in spring stiffness of the sleeper resilience pad could be cause changes in sleeper support conditions. The damage amount of manganese crossings that occurred during the current service period of about 21 years was investigated to be about 17% of the total amount of crossings, and it was analyzed that the damage amount increased after 15 years of use (accumulated passing tonnage of about 550 million tons). In this study, parameter analysis (wheel position, sleeper support condition, and dynamic wheel load) was performed using a three-dimensional numerical model that simulated real manganese crossing and wheel profile, to analyze the damage type and cause of manganese crossing that occurred in the actual field. As a result of this study, when the voided sleeper occurred in the sleeper around the nose, the stress generated in the crossing nose exceeded the yield strength according to the dynamic wheel load considering the design track impact factor. In addition, the analysis results were evaluated to be in good agreement with the location of damage that occurred in the actual field. Therefore, in order to minimize the damage of the manganese crossing, it is necessary to keep the sleeper support condition around the nose part constant. In addition, by considering the uniformity of the boundary conditions under the sleepers, it was analyzed that it would be advantageous to to replace the sleeper resilience pad together when replacing the damaged manganese crossing.

• Journal of the Korean Geosynthetics Society
• /
• v.22 no.2
• /
• pp.71-83
• /
• 2023

It is very important to predict the amount of settlement in order to maintain the function of the coastal structure. Finite element analysis methods and real and model experiments are used as methods for this, but this has the disadvantage of requiring a lot of cost and time. Therefore, this study was conducted for the purpose of a simple formula proposal that can easily predict the amount of settlement of the caisson-type quay wall structure. In the research process, after calculating the PSI (Power Spectrum Intensity) of the velocity, the amount of settlement of the structure is calculated by substituting it into the simple formula of the existing gravity breakwater. By comparing and analyzing the amount of settlement of the structure obtained through numerical analysis, it was confirmed that the error between the amount of settlement of the existing simple formula and the amount of settlement of the numerical analysis was large, and it was confirmed that the background could not be considered in the case of the existing simple formula. Therefore, this study proposed a correction factor for the background of the quay wall structure, indicating a simple formula that can obtain the amount of settlement of the caisson-type quay wall structure. Compared to the numerical analysis settlement amount, it was judged that this simple formula had sufficient precision in calculating the caisson-type quay wall settlement amount. In addition, facilities vulnerable to earthquake resistance can be easily extracted in situations where time and cost are insufficient, and it is expected to be used as a screening technique.

• Korean Association of Arts Management
• /
• no.52
• /
• pp.135-156
• /
• 2019

The purpose of this study is to derive more practical and concrete policy implications for the successful implementation of the Cultural City Designation Project, which is emerging as a main topic of cultural policy. To this end, the background and implementation system of the European Capitals of Culture(ECOC), which is the subject of benchmarking in various aspects, were examined. As a result, it was confirmed that there is a possibility that the Cultural City Designation Project can reveal its limitations in the background and process, and the improvement is as follows. First, rather than creating an ideal cultural city model to achieve its goals in a short period of time, efforts should be made to secure diversity and expand insufficient infrastructure in accordance with local autonomous decisions. Second, in order to secure the continuity of the business, it is necessary to secure and educate professional manpower for organizational operation in the form of independent or direct agency of each local government. Finally, careful policy consideration should be made at the national level to balance regional interests. Therefore, there is a need for an organized 'government-level organization' that can take on the role of the city selection process, support system, and ex post evaluation. In short, successful cultural city projects require critical acceptance and efforts to remedy fundamental problems rather than benchmarking unconditional overseas cases in terms of cultural policy.

• Journal of the Korean earth science society
• /
• v.44 no.1
• /
• pp.47-61
• /
• 2023

Rather than an abstract discourse, the purpose of this study is to outline the core concepts in the 2015 revised curriculum as a concrete teaching and learning method in the school context. We interviewed eight secondary science teachers and reported their perceptions and perspectives on core concepts using a backward design model based on the cyclical process of the platform, deliberation, and design for developing teaching and learning materials to understand core concepts. The participants perceived these core concepts differently, such as big ideas corresponding to the ultimate principle, minimum science concepts required for daily life, and primary and significant key concepts. In addition, this affects the association of teaching and learning. When core concepts are understood as transferable and expandable big ideas, there is a tendency to focus on the relationship between concepts and design project learning in a specific direction. However, if core concepts are identified as minimum science concepts at the level of science literacy, that can be recalled within the context of life, there is a tendency to emphasize on activities that make a meaningful difference to the lives of students with focus on case studies that are relevant to everyday life. Once core concepts are identified as key scientific content elements, such as basic or significant concepts, teachers recognize that it is essential to emphasize concept changes by correcting misconceptions, acquiring accurate scientific knowledge, and developing problem-solving items through paper-and-pencil evaluation. As the 2015 revised curriculum is finalized and the 2022 revised curriculum is scheduled for release, effective policy support is required to ensure that the curriculum is revised, which emphasizes the purpose of big ideas by naming core concepts as core ideas, to be stably implemented in schools.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.28 no.4D
• /
• pp.485-492
• /
• 2008

This study presents a viscoelastic characterization of flexible pavement subjected to moving loads. A series of field tests have been conducted on three pavement sections (A2, A5, and A8) at the Korea Expressway Corporation (KEC) test road. The effect of vehicle speed on the responses of each test section was investigated at three speeds: 25 km/hr, 50 km/hr, and 80 km/hr. During the test, both longitudinal and lateral strains were measured at the bottom of asphalt layers and in-situ measurements were compared with the results of finite element (FE) analyses. A commercial FE package, ABAQUS was used to model each test section and a step loading approximation has been adopted to simulate the effect a moving vehicle. For viscoelastic analysis, relaxation moduli of asphalt mixtures were obtained from laboratory test. Field responses reveals the strain anisotropy (i.e., discrepancy between longitudinal and lateral strains) and the amplitude of strain normally decreases as the vehicle speed increases. In most cases, lateral strain was smaller than longitudinal strain, and strain reduction was more significant in lateral direction.