• Title/Summary/Keyword: technology management

Search Result 25,553, Processing Time 0.048 seconds

Thermo-hydraulic Numerical Analysis for the Leakage of Buried District Heating Pipe (열수송관의 누수에 대한 열-수리적 수치해석)

  • Shin, Hosung;Hong, Seung-Seo
    • Journal of the Korean Geotechnical Society
    • /
    • v.38 no.3
    • /
    • pp.17-26
    • /
    • 2022
  • Domestic district heating system needs safety management guidelines using the change of surface temperature to detect damages to buried heat pipes. This paper performed numerical analyses on the temperature change of ground surface due to the burial and leakage of heat pipes. Temperature difference between the ground surface above the buried heat pipes and the surrounding surface rises to a crescendo between 3 am and 8 am. It is more significant in winter rather than in summer. Low groundwater level magnifies the temperature increase of the ground surface by the heat pipe, which is smaller in the asphalt pavement than in the bare soil. Without leakage of the buried heat pipe, the temperature increment on the ground surface by the heat pipe is within 3.0℃ in the bare soil and 3.5℃ in the asphalt pavement. Leakage of the supply heat pipe in the bare soil increases the temperature on the ground surface gradually in the summer but rapidly in the winter. Asphalt pavement shows a lower increment and increasing rate of the temperature on the ground surface due to pipe leakage than bare soil surface. And leakage on both sides of the supply pipe takes 1-2 days for the temperature difference from the surrounding soil surface to reach 10℃.

Study on the Effect of Emissivity for Estimation of the Surface Temperature from Drone-based Thermal Images (드론 열화상 화소값의 타겟 온도변환을 위한 방사율 영향 분석)

  • Jo, Hyeon Jeong;Lee, Jae Wang;Jung, Na Young;Oh, Jae Hong
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
    • /
    • v.40 no.1
    • /
    • pp.41-49
    • /
    • 2022
  • Recently interests on the application of thermal cameras have increased with the advance of image analysis technology. Aside from a simple image acquisition, applications such as digital twin and thermal image management systems have gained popularity. To this end, we studied the effect of emissivity on the DN (Digital Number) value in the process of derivation of a relational expression for converting DN to an actual surface temperature. The DN value is a number representing the spectral band value of the thermal image, and is an important element constituting the thermal image data. However, the DN value is not a temperature value indicating the actual surface temperature, but a brightness value indicating high and low heat as brightness, and has a non-linear relationship with the actual surface temperature. The reliable relationship between DN and the actual surface temperature is critical for a thermal image processing. We tested the relationship between the actual surface temperature and the DN value of the thermal image, and then the radiation adjustment was performed to better estimate actual surface temperatures. As a result, the relation graph between the actual surface temperature and the DN value similarly show linear pattern with the relation graph between the radiation-controlled non-contact thermometer and the DN value. And the non-contact temperature after adjusting the emissivity was closer to the actual surface temperature than before adjusting the emissivity.

International Comparison of Decoupling of Greenhouse Gas Emissions in the Steel Industry (철강산업의 온실가스 배출 탈동조화 국제비교)

  • Kim, Dong Koo
    • Environmental and Resource Economics Review
    • /
    • v.31 no.1
    • /
    • pp.113-139
    • /
    • 2022
  • The iron and steel industry is a manufacturing industry with the largest greenhouse gases emissions and has a great ripple effect on the national economy as a core material industry. This study internationally compared the decoupling patterns of greenhouse gases emissions in the iron and steel industry from 1990 to 2019, focusing on Korea, Japan, and Germany. In particular, unlike previous studies that considered only fuel combustion emissions, this study considered all fuel combustion emissions, industrial process emissions, and indirect emissions from the use of electricity and heat. As a result of the analysis, Korea is interpreted as expansive coupling, Japan as decoupling, and Germany as unclear. Therefore, the decoupling path that the Korean iron and steel industry should take should not be in Germany, but in the form of seeking a decoupling method similar to Japan or more effective than Japan. In addition, this study considered the characteristics of the iron and steel industry as much as possible and presented the causes of the decoupling analysis results and implications for the Korean iron and steel industry through comparison with Japan and Germany. In particular, four factors were suggested as factors which has promoted decoupling in Japan: high value-added of Japanese iron and steel products, development of energy efficiency technology in the Japanese iron and steel industry, strategic M&A of the Japanese iron and steel industry, and maintaining competitiveness according to the closed distribution structure of Japanese iron and steel products. The Korean iron and steel industry should also use the case of Japan as a benchmark to further increase added value through quality uprade and product diversification of iron and steel products, while at the same time making efforts to fundamentally reduce greenhouse gas emissions through the development of new technologies.

Effects of Electrolyte Cation on Electrochemical Properties of Negative and Positive Electrodes in Aluminum-Air Batteries (알루미늄-공기 전지의 음극 및 양극의 전기화학적 특성에 미치는 전해질 양이온의 영향)

  • Lee, Seunghwan;Yoon, Sungjae;Choi, Weon-Kyung;Baeg, Changhyun;Jeong, Soon-Ki
    • Journal of Convergence for Information Technology
    • /
    • v.12 no.2
    • /
    • pp.134-141
    • /
    • 2022
  • To improve the performance of aluminum-air batteries, it is very important to understand the effect of electrolytes on the electrochemical properties of electrodes. In this study, the effects of electrolyte cations on the electrochemical redox reactions proceeding at the negative and positive electrodes were investigated using electrolytes having the same anion but different cations such as NaCl, LiCl, CaCl2, and ZnCl2. It was confirmed by discharge test, scanning electron microscopy and X-ray diffraction analysis that electrolyte cations affect the discharge potential and specific capacity of the electrode. Precipitates were formed on the surface of the positive electrode by Ca2+ and Zn2+ ions, resulting in degradation of the performance of the positive electrode. In addition, Ca2+ ions passivated the negative electrode and accelerated the performance degradation. This suggests that the positive ions of the electrolyte have different effects on the electrochemical performance of the positive and negative electrodes.

A Study on the Trend Change using Trademark Information before and after COVID-19 (상표권 정보를 활용한 코로나19 전후의 트렌드 변화 연구)

  • Na, Myung-Sun;Park, Inchae
    • Journal of Convergence for Information Technology
    • /
    • v.12 no.2
    • /
    • pp.116-126
    • /
    • 2022
  • Many studies using trademark information have suggested that trademark information is good data to monitor business trends. This study intends to analyze the trend change before and after COVID-19 using trademark information. Changes before and after COVID-19 were analyzed by using goods & service classification, similar group code, and designated goods information as trademark information. Among the trademark information, it was statistically significant that the change in trends before and after COVID-19 using designated goods names. To verify the results, the changes in keywords using designated goods names before and after COVID-19 were compared with the frequency of keywords in Google Trends. Among the top 8 keywords extracted from designated goods names, the frequency of Google trend searches for 'online, antibacterial, prevention of epidemics, meal kit, virtual' is on the rise, and 'mask, droplet' is not on the rise, but it increased rapidly at the time of COVID-19, and even after COVID-19, it showed a higher level than before. The frequency of 'unmanned' does not differ much before and after COVID-19, but it has been maintained at a consistently high level, and related businesses have been active since before COVID-19, and it can be interpreted as a keyword with high public interest. This study has academic achievements in that it specifically identified information that could be used in business trends by using three types of trademark information.

High-efficiency deep geological repository system for spent nuclear fuel in Korea with optimized decay heat in a disposal canister and increased thermal limit of bentonite

  • Jongyoul Lee;Kwangil Kim;Inyoung Kim;Heejae Ju;Jongtae Jeong;Changsoo Lee;Jung-Woo Kim;Dongkeun Cho
    • Nuclear Engineering and Technology
    • /
    • v.55 no.4
    • /
    • pp.1540-1554
    • /
    • 2023
  • To use nuclear energy sustainably, spent nuclear fuel, classified as high-level radioactive waste and inevitably discharged after electricity generation by nuclear power plants, must be managed safely and isolated from the human environment. In Korea, the land area is limited and the amount of high-level radioactive waste, including spent nuclear fuels to be disposed, is relatively large. Thus, it is particularly necessary to maximize disposal efficiency. In this study, a high-efficiency deep geological repository concept was developed to enhance disposal efficiency. To this end, design strategies and requirements for a high-efficiency deep geological repository system were established, and engineered barrier modules with a disposal canister for pressurized water reactor (PWR)-type and pressurized heavy water reactor type Canada deuterium uranium (CANDU) plants were developed. Thermal and structural stability assessments were conducted for the repository system; it was confirmed that the system was suitable for the established strategies and requirements. In addition, the results of the nuclear safety assessment showed that the radiological safety of the new system met the Korean safety standards for disposal of high-level radioactive waste in terms of radiological dose. To evaluate disposal efficiency in terms of the disposal area, the layout of the developed disposal areas was assessed in terms of thermal limits. The estimated disposal areas were 2.51 km2 and 1.82 km2 (existing repository system: 4.57 km2) and the excavated host rock volumes were 2.7 Mm3 and 2.0 Mm3 (existing repository system: 4.5 Mm3) for thermal limits of 100 ℃ and 130 ℃, respectively. These results indicated that the area and the excavated volume of the new repository system were reduced by 40-60% compared to the existing repository system. In addition, methods to further improve the efficiency were derived for the disposal area for deep geological disposal of spent nuclear fuel. The results of this study are expected to be useful in establishing a national high-level radioactive waste management policy, and for the design of a commercial deep geological repository system for spent nuclear fuels.

A simple method to determine lycopene in solid supplementary food preparations using saponification and liquid chromatography (비누화 및 액체크로마토그래프를 활용한 고상 건강기능식품 중 라이코펜 분석법 개발)

  • Young Min Kim;Ye Bin Shin;Min Kyeong Kwon;Jin Hwan Kim;Ji Seong Kim;Dong-Kyu Lee;Myung Joo Kang;Yong Seok Choi
    • Analytical Science and Technology
    • /
    • v.36 no.3
    • /
    • pp.105-112
    • /
    • 2023
  • Lycopene, a carotenoid hydrocarbon is known to have effects on reducing cardiovascular risk factors, blood lipids, and blood pressure. Thus, a lot of supplementary foods with lycopene in several dosage forms like soft capsule filled with liquid and hard capsule filled with powder are available in a market. Recently, however, our research group found that the lycopene assay in Supplementary Food Code of South Korea is only valid for oily lycopene preparation. Thus, here, we developed a simple method to determine lycopene in solid preparations for Supplementary Food Code of South Korea using saponification and liquid chromatography with an absorbance detector. The method was validated following Ministry of Food and Drug Safety guidelines. All validation parameters observed in this study were within acceptable criteria of the guidelines (selectivity, linearity of r2 ≥ 0.991, lower limit of quantification of 0.0149 mg/mL, accuracy as recovery (R) between 92.70 and 97.18 %, repeatability as relative standard deviation (RSD) values of R between 0.85 and 1.59 %, and reproducibility as the RSD value of interlaboratory R of 3.70 %). Additionally, the practical sample applicability of the validated method was confirmed by accuracy between 98.81 and 101.59 % observed from its lycopene certified reference material (CRM) analyses. Therefore, the present method could contribute to fortify the supplementary food safety management system in South Korea.

A Study on the Performance Analysis of LINC+ Program (LINC+사업 성과 분석에 관한 연구)

  • Seo, Kyung-Hwa;Kim, Chang-Suk;Lee, Ju-Yeong;Han, Jung-Hee;Kim, Hyun-Soo;Han, Young-Jin;Jung, Young-Jin
    • Journal of Convergence for Information Technology
    • /
    • v.12 no.3
    • /
    • pp.186-192
    • /
    • 2022
  • This study investigated 110 contractual industries to identify the effects of curriculum development and educational environment improvement through Ulsan College LINC+ Program on job education and training. As a result of the study, core competency and job competency were 5.73 points each in field practice and educational environment, and job performance was significant with OJT 5.58 points and 5.74 points for educational environment(p<0.05). The relationship between suitability of the curriculum, educational environment, and recruitment performance was significant with 5.73 points for OJT, 5.74 points for field training during the education and training period, and 5.79 points for educational environment, and job reeducation/training expense was significant with 5.73 points for OJT and 5.79 points for educational environment(p<0.05). Also, students who completed the LINC+business curriculum shortened their job period by 1 to 6 months in 86.3% of the respondents, and responded that the education expense for new employees was reduced. Therefore, it was identified that the LINC+ Program of Ulsan College has the effect of shortening the job adaptation period and reducing education expenses for new employees by operating the curriculum reflecting the needs of the industry and improving the same educational environment as the industrial field.

Study on the Mathematics Teaching and Learning Artificial Intelligence Platform Analysis (수학 교수·학습을 위한 인공지능 플랫폼 분석 연구)

  • Park, Hye Yeon;Son, Bok Eun;Ko, Ho Kyoung
    • Communications of Mathematical Education
    • /
    • v.36 no.1
    • /
    • pp.1-21
    • /
    • 2022
  • The purpose of this study is to analyze the current situation of EduTech, which is proposed as a way to build a flexible learning environment regardless of time and place according to the use of digital technology in mathematics subjects. The process of designing classes to use the EduTech platform, which is still in the development introduction stage, in public education is still difficult, and research to observe its effects and characteristics is also in its early stages. However, in the stage of preparing for future education, it is a meaningful process to grasp the current situation and point out the direction in preparation for the future in which EduTech will be actively applied to education. Accordingly, the current situation and utilization trends of EduTech at home and abroad were confirmed, and the functions and roles of EduTech platforms used in mathematics were analyzed. As a result of the analysis, the EduTech platform was pursuing learners' self-directed learning by constructing its functions so that they could be useful for individual learning of learners in hierarchical mathematics education. In addition, we have confirmed that the platform is evolving to be useful for teachers' work reduction, suitable activities, and evaluations learning management. Therefore, it is necessary to implement instructional design and individual customized learning support measures for students that can efficiently utilize these platforms in the future.

Operational Strategies of a Bus-Exclusive Lane Using Barrier Transfer Systems to Control Tidal Traffic Flows (비대칭적 중방향 교통류 대응을 위한 이동식 중앙분리대 활용 버스전용차로 도입 전략 분석)

  • Kim, Taewan;Chung, Younshik;Jeon, Gyo Seok;Kim, Wongil
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.42 no.2
    • /
    • pp.209-217
    • /
    • 2022
  • Lane management with a central variable lane(s) (or reversible lane) where the traffic flow is temporarily reversed in one or more lanes during peak periods has been evaluated as an effective strategy to alleviate congestion caused by tidal traffic flows. However, due to traffic safety issues, such a movable barrier system can be considered as an alternative to supplement the existing its operation facilities such as static and/or dynamic signs and special pavement markings. In addition, when combined with a bus exclusive lane strategy, its effectiveness could be greatly increased. The objective of this study is to propose a feasibility analysis procedure for operational strategies of a bus-exclusive lanes using a barrier transfer system (BTS) for urban expressways. To this end, a case study was conducted on two urban expressways on the west side of the Han River in Seoul. As a result, temporary operation during rush hour in the morning was found to be most effective. The results presented in this study are expected to serve as a basis for establishing bus-exclusive lane operation strategies using similar systems in the future.