• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.20 no.8
• /
• pp.604-609
• /
• 2019

A variety of complaints about road signs have occurred for various reasons, such as new road facilities, new road signs such as road name signs, and an increase in nearby important facilities. In addition, there are many road signs that are in violation of road sign regulations. The basic principles of road signs, the connectivity of guide names, the location suitability, and a consistent road sign guidance system have not implemented. To solve these problems, various errors were investigated on major road signs on eight national highways, including direction signs, distance signs, boundary signs, and route signs. In addition, we classified the errors on road signs by grade to give them maintenance priority. We also analyzed the error status of signs for each route and grade. Based on the data, the problems of the road signs were derived, and an improvement plan is discussed. Based on this research, more systematic installation and management of road signs through cooperation between the government and local governments could increase the efficiency of road signs, as well as provide safer and more convenient road sign guidance systems for road users.

• Korean Journal of Construction Engineering and Management
• /
• v.20 no.1
• /
• pp.3-13
• /
• 2019

Recently, quality problems of steel used for construction have been raised as a cause of building collapse and safety accidents. Accordingly, it becomes more important to secure quality through material management, procurement management, and construction management for construction used steels. However, the quality management for construction used steels is confined to technical production and process control. So, it does not provide a solution of various non-conforming steel products issues. Therefore, this study suggests improvements of the construction system to secure quality of the construction used steels. Through expert interviews, we identify the items for system improvement and derive the top priority items by considering utility through a structured Analytic Hierarchy Process (AHP). It also divided the respondents into enterprise and research groups to analyze differences, implications and future improvement issues and suggest a road map. It is expected that the priority items derived in this study could be useful as a basic data for making policy decisions to assure the quality of construction used steel.

• The Korean Journal of Applied Statistics
• /
• v.31 no.6
• /
• pp.677-692
• /
• 2018

The total fertility rate of Korea was 1.05 in 2017, showing a return to the 1.08 level in the year 2005. 1.05 is a very low fertility level that is far from replacement level fertility or safety zone 1.5. The number may indicate a low fertility trap. It is therefore important to predict fertility than at any other time. In the meantime, we have predicted the age-specific fertility rate and total fertility rate by various statistical methods. When the data trend is disconnected or fluctuating, it applied a nonparametric method applying the smoothness and weight. In addition, the Bayesian method of using the pre-distribution of fertility rates in advanced countries with reference to the three-stage transition phenomenon have been applied. This paper examines which method is reasonable in terms of precision and feasibility by applying estimation, forecasting, and comparing the results of the recent variability of the Korean fertility rate with parametric, non-parametric and Bayesian methods. The results of the analysis showed that the total fertility rate was in the order of KOSTAT's total fertility rate, Bayesian, parametric and non-parametric method outcomes. Given the level of TFR 1.05 in 2017, the predicted total fertility rate derived from the parametric and nonparametric models is most reasonable. In addition, if a fertility rate data is highly complete and a quality is good, the parametric model approach is superior to other methods in terms of parameter estimation, calculation efficiency and goodness-of-fit.

• Journal of the Korean Data Analysis Society
• /
• v.20 no.6
• /
• pp.3087-3099
• /
• 2018

Due to the constant changes of companies' global networks, the expansion of global e-commerce as well as the market-oriented global supply chain management, global enterprises are strategically selecting and entering into viable countries able to become global footholds. Therefore, this study aims to scrutinize the trend of changes in the global networks of Korean companies by analyzing the current overseas countries over the past decade. From the analysis, it has been found that there is a significant difference in the priorities of targeting countries among shipping, manufacturing and logistics companies. Logistics companies preferred to enter Germany first while they attached to a lower priority to Singapore. Manufacturing companies had a lower priority to advance to India, while they preferred to advance to Mexico; however, shipping companies were analyzed to prefer to enter the US. In addition, all of these companies identified the importance of securing volume and network by entering overseas markets to achieve economies of scale and scope and to maintain global competitiveness. Joint overseas expansion of manufacturers with shipping and logistics companies can be recommended to facilitate the entry and thus, enhance global competitiveness and service capabilities and also secure new growth engines.

• Journal of Korean Society of Forest Science
• /
• v.108 no.1
• /
• pp.116-126
• /
• 2019

The production volume and amount of non-timber forest products in Korea has been on the increase for the past five years. In particular, the production amount of wild vegetables (edible mountain plants) is approximately KRW 400 billion as of 2017, accounting for 14 % of the total production amount of non-timber forest products. Among wild vegetables, especially the production volumes and amounts of bracken, saw-wort (Saussurea), and thistle have grown steadily. Nevertheless, severe price competition with cheap imports and little changes in the pattern of wild vegetable consumption may negatively affect the prices of domestic wild vegetables. This, in turn, can decrease the overall consumption of wild vegetables. Recently, however, consumers have preferred healthy food with increases in their income and interest in health. Therefore, now is a crucial time for the wild vegetable market. Accordingly, this study analyzed consumers' purchase and consumption behavior related to wild vegetables through a consumer survey to contribute to establishing various strategies and policies for promoting the consumption of these vegetables. Also, this study identified consumers' awareness and intention regarding wild vegetables by analyzing social big data. Different from previous studies, this study investigated consumers' awareness and intention by analyzing SNS social big data, as well as conducting a survey. The results of the study will help prioritize strategies and policies for boosting the consumption of wild vegetables.

• Journal of The Korean Association For Science Education
• /
• v.39 no.1
• /
• pp.143-160
• /
• 2019

This study investigated 15 science teachers' perception and practice on free semester and science assessment. We analyzed frequencies of teacher choice for closed questions and used constant comparative method for teacher description and individual interview. Most teachers determined a low ranking for changes in assessment methods and mentioned a lack of objectivity on free semester assessment, unsystematic free semester assessment, and more importance on student activity and interest in science instruction. Most teachers understood process-based assessment as a direction of free semester assessment and teachers mentioned positive aspects for students or teacher difficulties dependent on their perception on process-based assessment. Half of the teachers failed to implement student self-assessment and student peer-assessment due to subjectivity and complexity. Some teachers did not provide feedbacks to students due to a lack of time and did not use certain assessment methods due to a lack of knowledge of the assessment. Teachers who did not have an experience of discussions in a teacher learning community mentioned reasons regarding a small number of the same grade teachers and inactive attitude of colleagues. Teachers who did not participate in professional development programs mentioned a lack of teacher understanding of free semester, participation of the teacher in charge, and teacher choice of participation as reasons.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.22 no.3
• /
• pp.536-545
• /
• 2021

This study was conducted to investigate the effect of agarwood (Thymelaeaceae) inhalation using an electric incense burner on stress and brain waves. Sixteen participants were included in the study during the period from September 2019 to April 2020. Participant recruitment was undertaken by the 'H' center. This paper focused on stress reduction and compared the differences in stress and brain waves before and after agarwood inhalation using an electric incense burner. Electroencephalography was measured by a 19 Channel, Brainmaster Discovery, and analyzed using a NeuroGuide, LORETA (Brain Mapping). The analysis of technical statistics was carried out using SPSS/WIN 21.0 and the Wilcoxon signed-rank test. The study observed that the stress response index was reduced by a significance level of 0.01 in patients with anxiety, depression, and somatization disorders after agarwood inhalation. Secondly, alpha waves were increased by a significance level of 0.05, in 18 out of 19 regions measured, except FP 1. The difference after agarwood inhalation was the most significant in the region that affects emotion. Thirdly, a LORETA analysis found that alpha waves were increased in the brain region (BA 40) predominantly responsible for memory and emotion. This result clarifies that agarwood inhalation using an electric incense burner reduced stress and had a positive effect on brain waves and hence, has potential as an alternative therapy.

• Journal of Convergence for Information Technology
• /
• v.11 no.3
• /
• pp.140-146
• /
• 2021

As the environment using intelligent IoT devices increases, various studies are underway to ensure the integrity of information sent and received from intelligent IoT devices. However, all IoT information generated in heterogeneous environments is not fully provided with reliable protocols and services. In this paper, we propose an intelligent-based multi-blockchain model that can extract only critical information among various information processed by intelligent IoT devices. In the proposed model, blockchain is used to ensure the integrity of IoT information sent and received from IoT devices. The proposed model uses the correlation index of the collected information to trust a large number of IoT information to extract only the information with a high correlation index and bind it with blockchain. This is because the collected information can be extended to the n-tier structure as well as guaranteed reliability. Furthermore, since the proposed model can give weight information to the collection information based on blockchain, similar information can be selected (or bound) according to priority. The proposed model is able to extend the collection information to the n-layer structure while maintaining the data processing cost processed in real time regardless of the number of IoT devices.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.22 no.3
• /
• pp.390-397
• /
• 2021

The selective public-benefit direct payment is a system that provides subsidies to farmers that improve the public benefit of agriculture. However, there are limits in improving the public benefit since the current system simply integrates the prior direct payment system. Therefore, it is necessary to improve the public benefit of agriculture by reorganizing the implementation framework. This study uses the analytic hierarchy process and analytic network process to set the priority of the system and propose an implementation framework. A survey was conducted targeting 51 experts for about two months from August 2020. Study results show that the most important goal of the system is its effectiveness. The public beneficial implementation framework of the selective public-benefit direct payment is bundle type. Meanwhile, the effects of the subcategories of the bundle type lack research. Therefore, it is necessary to conduct a pilot project for the bundled type system and systematically establish policies by analyzing the effects of the pilot project. This study provided indicators about policy directions through the evaluation of the selective public-benefit direct payment (plan). The results of this study are expected to provide an objective basis for government policies related to the reform of selective public-benefit direct payment systems in the future.

• Journal of the Society of Disaster Information
• /
• v.18 no.1
• /
• pp.51-62
• /
• 2022

Purpose: This study analyzes accessibility of outdoor evacuation places for earthquake and the accessibility improvement effects when expanding the evacuation places in accessibility-deficient areas. In order to consider real-world evacuees, the accessibility analysis is based on service population not on resident population. Method: Location-allocation model as a GIS-based spatial optimization mode is used to analyze accessibility and vulnerable areas to evacuation places. Of location-allocation problem types, 'Maximize Coverage' method is chosen to allocate as many potential evacuees as possible to evacuation places. And impedence cutoffs or evacuation distances (times) are applied to three classes: 500m (7.5 minutes), 1,000m (15 minutes), and 1,500m (22.5 minutes). Case study area is Jung-gu areas, Seoul as a high-density downtown area. Result: Results show that accessibility-deficient areas and population to evacuation places are much more in service population than in resident population. Accessibility is significantly improved when increases when expanding the evacuation places in accessibility-deficient areas. Yet, accessibility-deficient areas are still remained since available lands are insufficient in the high-density downtown area. Conclusion: The study suggests that temporary evacuation facilities like outdoor evacuation places for earthquake need to consider real potential evacuees based not only on resident population but also on service population. Also, policy measures to provide emergency shelters need to more utilize spatial optimization tools like location-allocation model.