• Title/Summary/Keyword: foreign case study

Search Result 1,423, Processing Time 0.027 seconds

A study on the design of tunnel lining insulation based on measurement of temperature in tunnel (터널 온도계측을 통한 라이닝 단열 설계에 관한 연구)

  • Kim, Dea-Young;Lee, Hong-Sung;Sim, Bo-Kyoung
    • Journal of Korean Tunnelling and Underground Space Association
    • /
    • v.13 no.4
    • /
    • pp.319-345
    • /
    • 2011
  • In case of tunnels in cold regions, a freeze of groundwater around tunnel may act as a barrier of tunnel drainage in winter, or may cause the inner extrusion of lining. In spite of that, a design of insulation for preventing the frost damage of tunnel lining has not been introduced in Korea, while foreign countries such as Norway and so on have a standard on insulation. In this study, a few freezing cases of road tunnels have been reviewed, and the results show that the freezing protection is necessary. In order to characterize the thermal distribution in the tunnel, following measurements have been performed at Hwa-ak tunnel; the temperature distribution by longitudinal lengths, the internal temperature of lining and the temperature distribution of the ground under pavement. From these measurements, the characteristics of the tunnel's internal temperature distribution due to temperature change in the air has been analyzed. Based on the measurement results on the temperature distribution at Hwa-ak tunnel, thermal flow tests on the rock specimen with and without insulation have been performed in the artificial climate chamber to investigate the performance of the insulation. Also, a number of 3D numerical analyses have been performed to propose appropriate insulation and insulation thicknesses for different conditions, which could prevent the frost damage of tunnel lining. As a result of the numerical analysis, air freezing index of 291$^{\circ}C{\cdot}$ Hr has been suggested as the threshold value for freezing criteria of groundwater behind the tunnel lining.

A Study on the Gas-liquid Separation Effect of the Knockout Drum in the Flare System (플레어시스템에서 녹아웃드럼의 기·액 분리효과에 관한 연구)

  • Kwon, Hyun-Gil;Baek, Jong-Bae;Kim, Sang-Ryung
    • Journal of the Korean Institute of Gas
    • /
    • v.25 no.3
    • /
    • pp.1-8
    • /
    • 2021
  • Among the flare systems that handle discharged substances from safety valves, the knockout drum was a key facility for safety, but the installation standards were not clear, so it was necessary to review the standards acceptable to the workplace and regulatory agencies. After investigating the domestic and foreign technical standards of knockout drums and the deficiencies of previous studies, research was first conducted on the degree of mass discharge, the installation location of the intermediate knockout drum, and the effect of changes in the composition of the discharged material. As a result of the study under the process simulation conditions, the gas-liquid separation of the knockout drum was completed in a small amount of less than 7,500kg/hr. However, when more than that was released, the gas-liquid separation effect was small even with the addition of an intermediate knockout drum. In addition, when the composition ratio of the material easily condensed was increased (molar fraction 10%), the gas-liquid separation effect of the knockout drum increased in the case of mass release. The gas-liquid separation effect was analyzed to be greater when the knockout drum was installed adjacent to the stack than the knockout drum was installed adjacent to the process equipment.

Current State and Improvement of Safety Regulations of Working Platform and Working Passage in Construction Sites (건설현장 작업발판 및 가설통로의 안전기준 현황 및 개선점)

  • Jang, Jun Young;Ahn, Hongseob;Oh, Inhwan;Kim, Tae Wan
    • Journal of the Korea Institute of Construction Safety
    • /
    • v.2 no.1
    • /
    • pp.28-35
    • /
    • 2019
  • The average number of deaths in the construction industry reaches 500 per year, and in particular, it is confirmed that the type of accidents and deaths caused by disasters such as work platforms has occupied more than 60% of the total. In this study, we presented a structured and combined solution for technology, management, education, and cost that can solve systematically, politically, and external environmental factors as well as direct influence factors. In addition, we examined the safety and safety standards of domestic and international safety, and discussed implications. First, direct impact factors, organizational impact factors, policy influence factors, and external environmental impact factors were examined and classified into technical, education, and institutional dimensions. Second, in relation to the installation of the work scaffold, the standards (OSHA 1926.452), UK (The Work at Height Regulations 2005 No.735, BS5975), Japan (Labor Safety and Sanitation Regulations) and Germany (DIN 4420_4, DIN EN12810). In the case of domestic safety standards, similar to the foreign safety standards, safety measures such as materials and specifications are applied. However, details related to the installation, assembly and structure of the work platform are somewhat different from those in the United States and the United Kingdom excluding Japan. Using the results of this study, it is possible to understand the cause of the accident of foot pedestrian accident more systematically and comprehensively, and safety managers and researchers are expected to help in the accident investigation.

Evaluation of Domestic and Foreign Design Standards for Soil Nailing Method by Analysis of Slope Restoration Case (비탈면 복구사례 분석을 통한 쏘일네일링 공법의 국내외 설계기준 평가)

  • You, Kwang-Ho;Kim, Tae-Won
    • Journal of the Korean GEO-environmental Society
    • /
    • v.20 no.11
    • /
    • pp.11-22
    • /
    • 2019
  • Limit state design (LSD) and allowable stress design (ASD) are two main types of soil nailing design methodologies. In the LSD method, stability is determined by applying individual coefficients to ground strength, working load and etc. The ASD method calculates the safety factor and compares it with the minimum safety factor to determine the stability. The global design trend of soil nailing system is changing from the ASD method to the LSD method. The design method in Korea still adopts the ASD philosophy while others mostly do the limit state design. In this study, four soil nail design methods, 'FHWA GEC 7' in U.S. (2015), 'Clouterre' in France (1991), 'Soil nailing - best practice guidance' in U.K. (2005), 'Geoguide 7' in Hongkong (2008), and 'Design guide for slope in construction work' in Korea (2016) were applied to the evaluation of the stability and the results were analyzed comparatively in brief. It is revealed that the design method of 'the overall stability of soil nail walls' in Korea is the most conservative and next those by FHWA, Clouterre and CIRIA become more conservative in order. However, the difference of results obtained from FHWA and Clouterre is negligible. Also, this study found out that efforts to improve domestic design criterion are needed.

IPC Code Based Analysis of Technology Convergence of the IoT Patents in South Korea, China, and Japan : Focusing on PCT International Applications (한중일 사물인터넷(IoT) 관련 특허의 IPC 코드 기반 기술융복합 분석 : PCT 국제출원을 중심으로)

  • Shim, Jaeruen
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.24 no.7
    • /
    • pp.949-955
    • /
    • 2020
  • In this Study, Social Network Analysis of IoT related patents in South Korea, China, and Japan was conducted from the viewpoint of patent informatics. To this end, 2,526 patents filed by PCT until December 2019 were investigated up to the subclass level of the IPC code. As a result, in the case of South Korea, representative IPC codes are in the order of G06Q, H04L, G06F, H04W, and the highest frequency of interconnection is H04L→H04W, H04W→H04L, H04W→H04B. In China, the representative IPC codes are in the order of H04L, H04W, G05B, G06Q. South Korea has strong technological convergence centered on the G06Q, while China has strong convergence centered around H04L and H04W. Moreover, in China, H04L and H04W have more diverse combinations than in South Korea in Section A, B, G, and H. In the future, it is necessary to study the diversity of technology convergence of H04L and H04W in China.

A Study on the Current State of the Library's AI Service and the Service Provision Plan (도서관의 인공지능(AI) 서비스 현황 및 서비스 제공 방안에 관한 연구)

  • Kwak, Woojung;Noh, Younghee
    • Journal of Korean Library and Information Science Society
    • /
    • v.52 no.1
    • /
    • pp.155-178
    • /
    • 2021
  • In the era of the 4th industrial revolution, public libraries need a strategy for promoting intelligent library services in order to actively respond to changes in the external environment such as artificial intelligence. Therefore, in this study, based on the concept of artificial intelligence and analysis of domestic and foreign artificial intelligence related trends, policies, and cases, we proposed the future direction of introduction and development of artificial intelligence services in the library. Currently, the library operates a reference information service that automatically provides answers through the introduction of artificial intelligence technologies such as deep learning and natural language processing, and develops a big data-based AI book recommendation and automatic book inspection system to increase business utilization and provide customized services for users. Has been provided. In the field of companies and industries, regardless of domestic and overseas, we are developing and servicing technologies based on autonomous driving using artificial intelligence, personal customization, etc., and providing optimal results by self-learning information using deep learning. It is developed in the form of an equation. Accordingly, in the future, libraries will utilize artificial intelligence to recommend personalized books based on the user's usage records, recommend reading and culture programs, and introduce real-time delivery services through transport methods such as autonomous drones and cars in the case of book delivery service. Service development should be promoted.

Perception and Production of American English Vowels by Korean University Students (한국 대학생들의 미국영어 모음의 발화와 인지)

  • Cho, Mi-Hui
    • The Journal of the Korea Contents Association
    • /
    • v.21 no.5
    • /
    • pp.285-294
    • /
    • 2021
  • Motivated by the mixed results in the previous studies on the relationship between speech production and perception, the current study aims to investigate the relationship between production and perception in depth through a case study on how Korean EFL university students produce and perceive American English vowels. To this end, 19 Korean students at a university located in the Seoul-metropolitan area participated in the production and perception tests on American English vowels to elucidate the precedence relationship and the correlation between production and perception. Results showed that precedence of neither perception nor production was found in the overall result. However, either precedence of perception or production was found for the vowels [ɛ], [α], [ɔ], [u], which implies that the precedence relationship between production and perception varies depending on individual vowels. As for the correlation between production and perception, no correlation was attested between production and perception, suggesting that production and perception skills are not closely linked for these participants. Given that mastering language requires to coordinate two distinct production and perception skills and that L2 learners' preception and production skills become more closely connected as the learners' L2 experience and proficiency increases, no correlation between production and perception attested by the current EFL students implies that the correlation between production and perception varies during the course of foreign language/L2 acquisition in such a way that production and perception skills become increasingly related. Implications of the findings were further discussed and pedagogical suggestions were provided.

A Study on Implications and Improvement Plans for the Developing Consultation Guidelines for Environmental Assessment of Offshore Wind Power Development Projects (해상풍력 개발사업의 환경성 평가 협의 지침 개발에 관한 시사점 및 개선안 연구)

  • Haemi, Lee;Junho, Maeng
    • Journal of Environmental Impact Assessment
    • /
    • v.31 no.6
    • /
    • pp.449-464
    • /
    • 2022
  • This study reviewed the development process of the consultation guideline for the environmental assessment of offshore wind power. Based on this, implications and improvement plans for a future revision of the guidelines. Domestic and foreign case studies reviewed the consulting cases on domestic offshore wind power development projects, environmental location consulting cases, and guidelines related to overseas offshore wind power and analyzed location characteristics and significant environmental issues by project. Major environmental issues related to offshore wind power include birds, noise and vibration, marine animals and plants, marine physics, marine water quality and sediments, marine landscapes, and other auxiliary facilities installed on land. Implications and improvements for revising the consultation guidelines for evaluating offshore wind environments require data and clear guidelines at the central government level to determine areas where offshore wind projects can be located. In a situation where the importance of cumulative impact assessment is emphasized, guidelines for cumulative impact assessment methodologies for each item that reflect the domestic situation should be prepared for a cumulative impact assessment on offshore wind power environmental issues. In addition, when revising the consultation guidelines, empirical research cases should be reflected through the accumulation of environmental surveys and monitoring data of offshore wind farms by sea area.

A Study on the Evaluation and Improvement of Accessibility in Korean Online e-Journal (국내 온라인 학술지의 접근성 평가 및 개선에 관한 연구)

  • Boseong, Jang
    • Journal of the Korean Society for Library and Information Science
    • /
    • v.56 no.4
    • /
    • pp.161-180
    • /
    • 2022
  • This study aims to improve the accessibility of websites that can search for online e-journals and check the original text, and the accessibility of web contents in the form of article papers. In order to publish online e-journals in Korea, article contribution management system is used, and services are provided through public or private academic DB companies. There was no content related to accessibility in the publishing and editing stage of online e-journals. In the case of foreign countries, objective to comply with Level AA of WCAG 2.1 to improve accessibility of websites and web content. In addition, the level of accessibility of academic journals is guided through VPAT. In order to improve access to web content in online journals, Accessibility matters are added to the academic society's editorial and publication regulations. Accessibility education should be provided to journal editors. Accessibility checklists should be developed and researchers should verify themselves. To improve the accessibility of online e-journals to websites, For equal use, various convenience functions should be provided when using the website. It guides the accessibility function to the article contribution management system. Each academic and academic DB company should be required to submit a Korean VPAT.

A Study on the Altmetrics of the Papers of Library and Information Science Researchers Published in International Journals (국제 학술지에 발표된 문헌정보학 연구자 논문의 알트메트릭스에 관한 연구)

  • Jane Cho
    • Journal of Korean Library and Information Science Society
    • /
    • v.53 no.4
    • /
    • pp.143-162
    • /
    • 2022
  • Altmetrics is an alternative impact evaluation index that evaluates the social interest in the research performance of individuals or institutions in universities, research institutions, and research fund support institutions. This study empirically analyzed what kind of attention a papers of domestic library and information science researchers published in an international academic journal was receiving in the international community using Altmetric explorer. As a result of the analysis, 230 papers were tracked. The average Altmetric Attention Score (AAS) was 6.63, but there were 2 papers that received overwhelming attention (over 170 points) as they were mentioned in news report and Twitter. Second, there was a tendency for high AAS to appear in cases where a domestic researcher participated as a co-author and the main author belonged to an overseas institution, and in the case where the research funds were supported by foreign government agencies. In addition to the field of the library information science or information system, the papers classified as the field of public health service and education showed high AAS, and it was confirmed that these papers were published in the journals of various fields such as life science. Finally, it was confirmed that there was a weak correlation of r =0.25 between the AAS and the number of citations of the analyzed paper, but a strong correlation of r =0.68 between the number of Mendeley readers and the number of citations.