• Title/Summary/Keyword: ground continuity

Search Result 61, Processing Time 0.03 seconds

The Application of Standard in According to Ground and Electrical Continuity Testing of Lightning Protection Equipment in Field (피뢰설비현장의 접지 및 전기적 연속성 시험에 따른 표준적용)

  • Song, Gil-Mok;Koo, Kyung-Wan
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.63 no.4
    • /
    • pp.583-588
    • /
    • 2014
  • In this study, there are examined to the grounding of lightning protection system and electrical continuity tests in the field. The standard for lightning protection system is different design or construction according to the characteristics of the structure. Ground is measured and compared at least four locations. According to the measured results in the field, the sampled values of the ground resistance are measured $5{\Omega}$ or less and the difference between each value is suitable as $0.2{\Omega}$ or less. The values of the electrical continuity test between ground and metal bodies are measured 3 groups such as isolated portion, the mechanical contacted portion, and the electrical continuity portion measuring $0.2{\Omega}$ or less. It is measured to be less than $0.2{\Omega}$ at all in metal bodies of underground. A metal body installed inside the structure is not isolated, but the resistance values are higher than $0.2{\Omega}$. Therefore, It must be carried out the structure having lightning protection system confirm the LPL(lightning protection level) and design the strategy.

Evaluation of Steelwork Continuity within Reinforced Concrete Apartment Structures (철근콘크리트 아파트의 철근구조체에 대한 전기적 연속성 평가)

  • Lee, Ki-Hong;Lee, Taek-Soeb;Kim, Oun-Seok
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
    • /
    • 2005.11a
    • /
    • pp.125-127
    • /
    • 2005
  • This paper conducted to evaluate electrical continuity of steelworks within reinforced concrete apartment structures as the down conductor in external lightning protection system. The reinforcing bars in reinforced concrete structures can be used as the down conductor when their overall electrical resistance is not greater than the resistance value of 0.2 ohm between the uppermost part and the ground level. According to the results of electrical resistances measured by 4-terminal low resistance measurements, the steelworks in reinforced concretes structures exhibited the electrical continuity with low electrical resistance.

  • PDF

A Study on Architectural Continuity of the Memorial to the Murdered Jews of Europe (유럽의 학살된 유대인을 위한 기념비 건축의 연속성에 관한 연구)

  • Kim, Myungshig
    • Journal of the Architectural Institute of Korea Planning & Design
    • /
    • v.35 no.12
    • /
    • pp.83-92
    • /
    • 2019
  • The purpose of this study is to analyze the continuous forms of time and space that work as architectural design principles of the Memorial to the Murdered Jews of Europe (Jewish Memorial). Continuity is divided into two, physical and non-physical attributes. The former extends from small installations to furnitures, finishes, spatial composition, and even spatial networks that complete architecture, and the latter is tied to time, from traditional to historical, developmental, commemorative or memorial elements. They are inherent in architecture as continuous forms. The Jewish Memorial is analyzed by the analysing framework of these two items. The analysis of the two layers can be summarized as follows; physical continuity is found in the space networks of the Memorial's inside and outside, the undulating spaces, the finishes, the small furnitures and installations, the entrances of staircases, the expanded underground of the ground order, and non-physical continuity manifests in the topological variation of spatiality, the morphological development of memorial architecture, the connection of semantic sense of space, and the superposition of historicity and modernity. These forms of continuity do not aestheticize the German enormity history, but make the meaning of the Memorial into non-superficial, in-depth architecture as a monument. Thus, the results of this study show that physical and non-physical continuity should be considered as the important design principles of architecture that makes the Memorial architecture possible.

Continuity of Care in Chronic Diseases: A Concept Analysis by Literature Review

  • Hu, Jingjing;Wang, Yuexia;Li, Xiaoxi
    • Journal of Korean Academy of Nursing
    • /
    • v.50 no.4
    • /
    • pp.513-522
    • /
    • 2020
  • Purpose: This study aimed to utilize concept analysis to obtain a better understanding of the concept of "continuity of care" in chronic diseases. Methods: The concept of continuity of care was analyzed using the Walker and Avant method. Covering literature in English from 1930 to 2018, the data sources included CINAHL Complete, Academic Search Complete, MEDLINE, PsyARTICLES, Health Source: Nursing/Academic Edition, Google Scholar, Science Direct, and the Cochrane Library. Results: A comprehensive definition of concept of continuity of care was developed based on a systematic search and synthesis. The key defining attributes were identified as (a) care over time, (b) the relationship between an individual patient and a care team, (c) information transfer, (d) coordination, and (e) meeting changing needs. The antecedents of continuity of care were having a chronic disease, inexperienced with disease management, a poorly coordinated healthcare system, and medical care limitations. The consequences of continuity of care were decreasing hospital admissions, reducing costs, reducing emergency room visits, improving the quality of life, improving patient satisfaction, and delivering good healthcare. Conclusion: The thorough concept analysis provides insight into the nature of "continuity of care" in chronic diseases and also helps ground the concept in healthcare.

A Study on the Risk Assessment Occurred Possibly in a Civil Project (토목공사에서 발생 가능한 리스크평가에 관한 연구)

  • Yoon, Yong-Kyun
    • Explosives and Blasting
    • /
    • v.29 no.2
    • /
    • pp.59-66
    • /
    • 2011
  • A variety of risks caused by natural, technological and biological hazards threaten a business continuity of an organization. Business continuity is very important issue for all organizations and its proper management may control success and failure of an organization. Business continuity plan (BCP) may be defined as a management process which provides a business continuity. BCP includes risk management, operational continuity plan, response/ recovery, exercise/study and crisis communication, etc. Risk management is a systematic method to identify, analyze, evaluate and treat emergency risks and risk assessment is composed of identifying, analyzing and evaluating emergency risks. Risk assesment is the first step for making BCP. In this study, risk assessment has been conducted for sewer laying project. Through assessing risks, 18 risks that may threaten the construction operation are identified and it is founded to be that high levels of risks which require treatment are 'collapse of excavation surface', 'breakage of ground infra-facilities', 'noise & dust dispersion' and 'rise of material costs'.

Quality and Measure Controls for Plastic Board Drains Method (PBD공법의 품질 및 계측관리)

  • 박영목
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2001.10a
    • /
    • pp.133-145
    • /
    • 2001
  • This paper presents quality and measure controls of Plastic Board Drains(PBD) for improvement of soft ground. Laboratory and field tests has been carried out to evaluate the quality of PBD focussing on : discharge capacity of flow area; permeability of filter sleeve; migration of fine particles; deformed shape of PBD; consolidation of clay in the close vicinity of PBD; tensile strength of PBD; long-term consolidation behavior of clay-PBD. Test results show that the quality of PBD is sufficient to perform the improvement of soft silty and clayey ground. But, geotechnical engineer must make efforts minimizings of PBD damage and ground disturbance, continuity of drainage system during construction. Adequate monitoring system should apply at ground focussing on number, location, and accuracy of geotechnical instrumentation, measurement and evaluation of data for ground behaviour.

  • PDF

An intelligent semi-active isolation system based on ground motion characteristic prediction

  • Lin, Tzu-Kang;Lu, Lyan-Ywan;Hsiao, Chia-En;Lee, Dong-You
    • Earthquakes and Structures
    • /
    • v.22 no.1
    • /
    • pp.53-64
    • /
    • 2022
  • This study proposes an intelligent semi-active isolation system combining a variable-stiffness control device and ground motion characteristic prediction. To determine the optimal control parameter in real-time, a genetic algorithm (GA)-fuzzy control law was developed in this study. Data on various types of ground motions were collected, and the ground motion characteristics were quantified to derive a near-fault (NF) characteristic ratio by employing an on-site earthquake early warning system. On the basis of the peak ground acceleration (PGA) and the derived NF ratio, a fuzzy inference system (FIS) was developed. The control parameters were optimized using a GA. To support continuity under near-fault and far-field ground motions, the optimal control parameter was linked with the predicted PGA and NF ratio through the FIS. The GA-fuzzy law was then compared with other control laws to verify its effectiveness. The results revealed that the GA-fuzzy control law could reliably predict different ground motion characteristics for real-time control because of the high sensitivity of its control parameter to the ground motion characteristics. Even under near-fault and far-field ground motions, the GA-fuzzy control law outperformed the FPEEA control law in terms of controlling the isolation layer displacement and the superstructure acceleration.

Methodology of Parallel Ground Conductor Installation on Underground Transmission System (지중송전 시스템의 병행지선 설치 방안 연구)

  • Hong, Dong-Suk;Park, Sung-Min;Hahn, Kwayng-Hyun
    • Proceedings of the KIEE Conference
    • /
    • 2008.07a
    • /
    • pp.470-471
    • /
    • 2008
  • SVL is installed at underground transmission system to protect cables and insulation joint-box from overvoltages caused by lightning, switching, and line-to-ground fault. Domestic underground power system adopts cross bonding type to reduce the induced voltage at sheath, but single-point bonding is required depending the system installation configuration. SVL can be easily broken by overvoltages induced at joint-box because single-point bonding has uneffective system structure to extract fault current. ANSI/IEEE recommends Parallel Ground Continuity Conductor(PGCC) to prevent SVL breakdown. In this paper, EMTP simulation is performed to analyze effects on SVL under PGCC installation when single-line-to-ground fault occurs. The result shows that PGCC and short single-point bonding distance can reduce overvoltages at SVL.

  • PDF

Verification of Validity on Awareness Tool of Business Continuity for Railway Organizations (철도기관을 대상으로 한 사업연속성 인식도구의 타당성 검증)

  • Jeong-ho Chang;Chong-soo Cheung
    • Journal of the Society of Disaster Information
    • /
    • v.19 no.1
    • /
    • pp.195-203
    • /
    • 2023
  • Purpose: This study intends to check validity of tools for awareness of Business Continuity through measurement and analysis on the sub factors of Business Continuity by employees of railway-related organizations. Method: Based on the preceding study, sub factors of the awareness of Business Continuity are divided into 7 and the total of 29 questions were delivered to employees of railway-related organizations for investigation and analysis through the online survey tool. Result: According to EFA result, the number of factors of awareness of Business Continuity based on the theoretical ground was reduced to 7 and the total coefficient of determination was 82.616%. Checking the questions by factor, all the questions were loaded as intended. Conclusion: Validity of measurement tools of Business Continuity whose sub factors are the Context of Organization, Leadership, Planning, Operation, Support, Performance evaluation, and Improvement for railway organizations were secured through the Exploratory Factor Analysis of this study. As for the further tasks, studies on the structural relationship among internalization of business continuity, organization effectiveness, learning support environment, etc are required.

Navigation Performance Analysis of KASS Test Signals

  • Daehee Won;Eunsung Lee;Chulhee Choi
    • Journal of Positioning, Navigation, and Timing
    • /
    • v.12 no.4
    • /
    • pp.369-377
    • /
    • 2023
  • This paper presents the analysis results of navigation performance of Korea Augmentation Satellite System (KASS) test signals. Performance analysis was performed with Global Positioning System (GPS) and Satellite Based Augmentation System (SBAS) signals received from 7 KASS reference stations. And the performances were analyzed in terms of the signal strength, statistics for each SBAS message, coverage of ionospheric correction, accuracy, integrity, continuity, and availability. In addition, the navigation solutions provided by commercial receiver was analyzed and the performance experienced by general users was presented. Lastly, directions for further improvement of the KASS system were addressed. These performance analysis results can be used to confirm the feasibility of utilizing KASS in user applications.