• Title/Summary/Keyword: distribution board management system

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Manufacturing and Characteristics Analysis of a Testing Device for the Evaluation of a Distribution Board Management System (분전반 관리시스템 평가를 위한 시험 장치의 제작 및 특성 분석)

  • Ko, Wan Su;Lee, Byung Seol;Choi, Chung Seog
    • Journal of the Korean Society of Safety
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    • v.34 no.5
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    • pp.31-36
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    • 2019
  • This study made a testing device to evaluate the distribution board management system. Power was supplied to the testing device using a loading-back method and the voltage applied to it was 440 V at the same turn ratio. When the human body electric shock current is 30 mA, the breaking time is set to be less than 240 ms while 30~45 mA current is flowing. The test result shows that in the case of the R-phase it was measured to be 5.19 Hz (193 ms). And the S-phase and T-phase were perfectly cut off at 5.39 Hz (186 ms) and 5.71 Hz (175 ms), respectively. When the human body electric shock current is 60mA, the breaking time is set to be less than 120 ms while 45~75 mA current is flowing. The test result shows that the R-phase, S-phase, and T-phase were accurately cut off at 8.39 Hz (11 ms), 8.87Hz (113 ms) and 9.69 Hz (103 ms), respectively. When the human body electric shock current is 90 mA, the breaking time is set to be less than 48 ms while 75 mA current is flowing. The test result shows that the R-phase, S-phase, and T-phase were accurately cut off at 19.8 Hz (50.4 ms), 16.9 Hz (59.2 ms), and 17.9 Hz (56.0 ms), respectively. That is, the developed testing device satisfied all the requirements of the distribution board evaluation criteria, and it becomes available for the performance evaluation of the distribution board management system.

Development of a Customer Friendly GIS-based Disaster Management System in South Korea

  • SONG, Wanyoung;CHOI, Junho;LEE, Dongkwan;CHOI, Choongik
    • Journal of Distribution Science
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    • v.17 no.11
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    • pp.27-34
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    • 2019
  • Purpose: This study explored the improvement and the direction of the smart disaster management system newly attempted in South Korea by analyzing the utilization of the existing system. This study focuses on making it easy to apply to user tasks and improving on site information. Research design, data and methodology: Problems were identified through field surveys with administrators in charge of administration and public institutions based on GIS based status board for NDMS which is widely used in Korea. Also, this study attempted to generalize to specialists in disaster management who are more likely to use the system in the future. Results: We derived improvement plans and verified the results through expert feedback. The results show that the GIS based status board for NDMS is cumbersome to use due to the vast array of unnecessary information compared to the high expected utilization. Conclusions: We found that improving the speed and accuracy of the smart disaster management information delivery system is necessary. Also, it is important to identify reasons for not improve the willingness to use this technology in disaster management and to figure out the process by which field personnel makes decisions that smart disaster information cannot be used for disaster management.

A Study on Job Sequence and Feeder Allocation Problem in PCB Assembly Line (PCB 조립 공정의 작업 투입 순서 및 부품함 배치 문제에 관한 연구)

  • Yu, Sung-Yeol;Lee, Kang-Bae
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.29 no.1
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    • pp.63-71
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    • 2006
  • In this paper, we consider a planning problem arising from printed circuit board manufacturing industries. Given a set of several types of PCBs, component feeders and surface mounting machines in series in a PCB assembly line, the problem is to define the feeder allocation and job sequence with the objective of minimizing the total operation time of the line. We formulate the problem as a mathematical model. And, the problem is proven to be NP-hard, so a genetic algorithm is developed. Finally, we give test results to evaluate the performance of the genetic algorithm.

A Study on Development of Integrated System of Ship's Information (선박종합정보시스템의 개발에 관한 연구)

  • Jeong, Tae-Gweon;Park, Soo-Han
    • Journal of Navigation and Port Research
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    • v.31 no.8
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    • pp.645-652
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    • 2007
  • As a method to improve the present operational and safe function in navigation this paper developed an efficient and economical integrated system of ship's information. This system is, systematically and comprehensively, to monitor, save, analyse, and display information on navigation and environment around own ship in real time by connecting one user to another through an on-board LAN or data communication via satellite so that many users on board can obtain simultaneously and easily the information in real time not only in the wheelhouse and engine room but also in many robins and ship's offices. And it consists of four(5) components; data distribution program, database of navigational and engine-related information, multi-functional monitoring program, ship management program and other application program.

The JASIST Editorial Board Members' Research Areas and Keywords of JASIST Research Articles (JASIST 편집위원회의 연구분야와 JASIST 논문의 키워드에 관한 연구)

  • Kim, Hyunjung
    • Journal of the Korean Society for information Management
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    • v.31 no.3
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    • pp.227-247
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    • 2014
  • This paper examines the characteristics of the JASIST (Journal of the Association for Information Science and Technology) editorial board members and their research areas through author co-citation analysis, and investigates whether the editorial board members' research areas are related with keywords frequently appeared in the journal's research articles. In the process, research areas of the central members and those appeared most frequently as keywords will be identified. Research areas of the 36 members on the JASIST editorial board are collected and categorized to compare with the categorization of keywords extracted from 169 research articles published in JASIST, 2013. The result shows that members with higher centrality in the co-citation network are related with research areas that are also dominant in the distribution of article keywords. The areas include information behavior and searching, information retrieval, information system design, and bibliometrics.

Corporate Governance and Capital Structure Decisions: Evidence from Chinese Listed Companies

  • VIJAYAKUMARAN, Sunitha;VIJAYAKUMARAN, Ratnam
    • The Journal of Asian Finance, Economics and Business
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    • v.6 no.3
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    • pp.67-79
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    • 2019
  • This study examines the impact of corporate governance on capital structure decisions based on a large panel of Chinese listed firms. Using the system Generalized Method of Moments (GMM) estimator to control for unobserved heterogeneity, endogeneity, and persistency in capital structure decisions, we document that the ownership structure plays a significant role in determining leverage ratios. More specially, we find that managerial ownership has a positive and significant impact on firms' leverage, consistent with the incentive alignment hypothesis. We also find that managerial ownership only affects the leverage decisions of private firms in the post-2005 split share reform period. State ownership negatively influence leverage decisions implying that SOEs may face fewer restrictions in equity issuance and may receive favourable treatments when applying for seasoned equity ¿nancing, thus use less debt. Furthermore, our results show that while foreign ownership negatively influences leverage decisions, legal person shareholding positively influences firms' leverage decisions only for state controlled firms. We also find that the board structure variables (board size and the proportion of independent directors) do not influence firms' capital structure decisions. Our findings suggest that recent ownership reforms have been successful in terms of providing incentive to managers through managerial shareholdings to take risky financial choices.

Corporate Social Responsibility and Earnings Management: Evidence from Saudi Arabia after Mandatory IFRS Adoption

  • GARFATTA, Riadh
    • The Journal of Asian Finance, Economics and Business
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    • v.8 no.9
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    • pp.189-199
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    • 2021
  • This study attempts to examine the relationship between corporate social responsibility (CSR) disclosure and earnings management practices in the context of Saudi Arabia after mandatory IFRS adoption. It is carried out on an unbalanced panel of 277 observations over the period 2017-2019. For this purpose, CSR disclosure is measured by Bloomberg ESG scores, while the residuals from the modified Jones model are considered for earnings management. As control variables, we have retained the firm performance, market-to-book ratio, firm size, financial leverage, board independence, ownership concentration, managerial ownership, and lagged discretionary accruals. Using the system GMM estimator in the dynamic panel, the results show a positive association between CSR disclosure and earnings management practices, thus supporting the perspective of agency theory. Managers engage in socially responsible activities beforehand to conceal their wrongdoing and convince stakeholders that the organization is transparent. They probably use ethical codes as a tool to achieve their own goals rather than the firm's goals. Our contribution is the use of recent data (2017-2019) taking into account the mandatory adoption of IFRS in Saudi Arabia. Additionally, to our knowledge, this study is the first to address CSR disclosure and earnings management practices using GMM system estimates.

A Study on Development of Integrated System of Ship's Information (선박종합정보시스템의 개발에 관한 연구)

  • Jeong, Tae-Gweon;Park, Soo-Han
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • v.1
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    • pp.15-22
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    • 2006
  • As a method to come up with the low competence of responsible officers, an integrated system providing watch officers with information on navigation obtained on board and on land as well is needed to secure the safety of navigation. Therefore as an approach to improve the function for safe navigation, this paper is to develop, efficiently and economically, an integrated system of ship's information.

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Heterogeneous Equipment Support Monitoring System for Operation and Maintenance of Solar power plant (태양광발전소 운영유지보수를 위한 이기종 장비 지원 모니터링 시스템)

  • Lim, Su-Chang;Hong, Seok-Hoon;Park, Chul-Young;Cho, Hyun-Wook;Song, Beob-Seong;Kim, Jong-Chan
    • Journal of Korea Multimedia Society
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    • v.23 no.9
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    • pp.1171-1180
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    • 2020
  • The number of the PV systems installed in south korea has been gradually increasing. Interest of operation & management of PV System is rising up as PV System installation trends to increase. The vital function of operation & management is the monitoring system. Most monitoring systems are only available for equipment of suppliers and manufacturers. In this study, a monitoring system was implemented to support multi-domain equipment (inverter, junction box, water distribution board, environmental sensors) that are not limited to specific manufacturers. Monitoring system includes a visualization function, which makes it easy for users to check the power generation and the operation status of the equipment of PV System. In the future, this monitoring system will be utilized as an operation & maintenance foundation element in the PV system industry.

Analysis of the Frequency , Criticality and Difficulty of Each Job Task Elements for the Validity of the Dietitian's Job Description (영양사 직무기술서 내용 타당성 검증을 위한 각 직무의 빈도 , 중요도 , 난이도 분석)

  • Mun, Hyeon-Gyeong;Lee, Ae-Rang;Lee, Yeong-Hui;Jang, Yeong-Ju
    • Journal of the Korean Dietetic Association
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    • v.7 no.1
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    • pp.105-116
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    • 2001
  • This study was conducted a part of the project developing the standards of national board test for the dietitian's licence. The purpose of this study was to verify the dietitian's job description. To do this the survey was carried out for the frequency, criticality and difficulty of each job description with 4 point scales. The subjects was 521 dietitians, who have been working over 3 years at their position. The results are following ; 1. The each duty, task and task elements are verified with survey results. 2. Duties with high frequency and criticality were menu management, purchasing, storage and stock management, operational management for cooking, system management for distribution and sanitation management. 3. Duties with middle frequency and high criticality were managing equipment and facility, food service management, human resources management and self-development. 4. Duties with low frequency and high criticality were nutritional assessment for life cycles, nutrition therapy, nutrition education and disease management. 5. For difficulty, food service area show lower than of nutrition service area.

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