• Title/Summary/Keyword: current collection system

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A Study on Dynamic Design of Current Collection System for the Korean High Speed Train (한국형 고속전철 집전 시스템의 동적설계에 관한 연구)

  • Hur, Shin;Kyung, Jin-Ho;Song, Dahl-Ho
    • Proceedings of the KSR Conference
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    • 1998.11a
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    • pp.445-452
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    • 1998
  • The dynamic performance design of catenary-pantograph system which collects current for the next generation Korean high speed train(KHST) was considered. Used was the same dynamic model of the catenary-pantograph system as that of TGV-K which will be introduced for Kyung-bu corridor. Using the model , sensitivity analysis fer design variables were made to improve dynamic performance of KHST system. The results of sensitivity analysis and performance improvement are as follows: (1) It was found that aerodynamic force, tension of contact wire, mass of contact strip, mass of supporting contact strip, mass of clamp, mass of steady arm, and stiffness of plunger were the design variables most influencing the dynamic performance of the system. (2) Pantograph with reductions of 20% aerodynamic force, 34% weight of supporting contact strip, 20% spring constant of plunger, and 34% equivalent mass of steady arm was very possible system for the KHST which will be running at maximum operating speed 350 km/h.

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A Survey and Analysis of Current Collection Management State in School Libraries (학교도서관의 장서관리 현황조사 및 분석)

  • Kim, Sung-Jun;Lee, Byeong-Ki
    • Journal of Korean Library and Information Science Society
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    • v.48 no.1
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    • pp.21-42
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    • 2017
  • This study reports the result of the survey on collection management from 154 school libraries in Korea. The questionnaire is consisted of three section: state of collection, state of book use, and collection management system. Results reveal that (1) elementary schools and middle schools have many books for each student compared to the KLA's School Library Standards; (2) the component ratio of literature books is the biggest in school library collections; (3) the ratio of library book use is overwhelmingly higher in elementary schools than middle schools and high schools; (4) 64.6 percent of library books in the sample are never used during 2013-2015; (5) 74 percent of libraries have its own collection management document; (6) Almost all schools compose its own committee for library management, the committee plays an important roles in the communication among school members, collection development and promotion.

The Agriculture Decision-making System(ADS) based on Deep Learning for improving crop productivity (농산물 생산성 향상을 위한 딥러닝 기반 농업 의사결정시스템)

  • Park, Jinuk;Ahn, Heuihak;Lee, ByungKwan
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.11 no.5
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    • pp.521-530
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    • 2018
  • This paper proposes "The Agriculture Decision-making System(ADS) based on Deep Learning for improving crop productivity" that collects weather information based on location supporting precision agriculture, predicts current crop condition by using the collected information and real time crop data, and notifies a farmer of the result. The system works as follows. The ICM(Information Collection Module) collects weather information based on location supporting precision agriculture. The DRCM(Deep learning based Risk Calculation Module) predicts whether the C, H, N and moisture content of soil are appropriate to grow specific crops according to current weather. The RNM(Risk Notification Module) notifies a farmer of the prediction result based on the DRCM. The proposed system improves the stability because it reduces the accuracy reduction rate as the amount of data increases and is apply the unsupervised learning to the analysis stage compared to the existing system. As a result, the simulation result shows that the ADS improved the success rate of data analysis by about 6%. And the ADS predicts the current crop growth condition accurately, prevents in advance the crop diseases in various environments, and provides the optimized condition for growing crops.

A Flash Memory Swap System for Mobile Computers (모바일 컴퓨터를 위한 플래시 메모리 스왑 시스템)

  • Jeon, Seon-Su;Ryu, Yeon-Seung
    • Journal of Korea Multimedia Society
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    • v.13 no.9
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    • pp.1272-1284
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    • 2010
  • As the mobile computers are becoming powerful and are used like general-purpose computers, operating systems for mobile computers also require swap system functionality that utilizes main memory efficiently. Flash memory is widely used as storage device for mobile computers but current linux swap system does not consider flash memory. Swap system is tightly related with process execution since it stores the contents of process in execution. By taking advantage of this characteristics, in this paper, we study a new linux swap system called PASS(Process-Aware Swap System), which allocates the different flash memory blocks to each process. Trace-driven experimental results show that PASS outperforms existing linux swap system with existing garbage collection schemes in terms of garbage collection cost.

A Study on "the Shared Acquisition System of Occidental Journals" of "University Library Information Cooperation Council in Pusan-Kyungnam Area" (부산.경남지역 대학도서관 정보교류협의회 외국학술잡지 분담수설시스템에 관한연구)

  • 송영희
    • Journal of Korean Library and Information Science Society
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    • v.33 no.4
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    • pp.241-259
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    • 2002
  • This paper is a study on the current statues of the shared acquisition system of occidental journals in 6 university libraries belonging to Pusan-Kyungnam Area University Information Cooperation Council. The study discusses theoretical background of a shared acquisition in general and historical development and analyzes the current status of the system. Also the study examines the usefulness. effectiveness and problems of the system.

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A Study on Smart Trash Can and User UX Designs: A Software Engineering Approach for Health Care

  • Yoon, Jun-Ho;Bae, Geun-Pyo;Huh, Jun-Ho
    • Proceedings of the Korea Information Processing Society Conference
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    • 2017.04a
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    • pp.725-727
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    • 2017
  • In this study, a function that informs the trash can users about daily collectable trash types and the visiting schedule of collection trucks with an application-based push alarms is proposed along with other function that lets the user to receive the information regarding the volume of trash cans located near his/her residence and monthly average trash volume once the user registers his/her personal information online. This functions are used for the UX design between smart trash can and users. The proposed system allows trash collection trucks to find the most efficient path from their current positions by finding out users' trash can volumes in advance. The UX design and the smart trash can system proposed in this study aim to improve the trash processing efficiency by allowing users to check the volume of their trash.

The Survey on the Use of Book Numbers System in South Korean Academic Libraries

  • Park, Jae-Yong
    • Management & Information Systems Review
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    • v.19
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    • pp.83-104
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    • 2006
  • This study investigated the actual condition of book numbers in South Korean academic libraries. Book numbers that are used in the Korean academic libraries consist of a combination of author-number or author-name, the first letter of the title, and any other shelflisting device. This study examined the current problems that perceive academic librarians on book numbers and the problem awareness of librarians who are working at 110 academic libraries in South Korea. The result shows that academic libraries are using eleven different methods of the book numbers table including nine eastern methods and two western methods. Also, librarians mentioned that the crucial concerns among participating libraries were the duplication of the book numbers and ineffective collection management. Therefore, this study suggested the expansion of the book numbers system in order not to duplicate of book numbers and the unification of western and eastern methods so that academic libraries tackle problems of ineffective collection management.

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Advanced Protective Relaying Algorithm by Flux-Differential Current Slope Characteristic for Power Transformer (전력용 변압기용 자속-차전류 기울기 특성에 의한 개선된 보호계전 알고리즘)

  • 박철원;신명철
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.53 no.7
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    • pp.382-388
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    • 2004
  • The most widely used primary protection for the internal fault detection of power transformers is current percentage differential relaying(PDR). However, the harmonic components could be decreased by magnetizing inrush when there have been changes to the material of iron core or its design methodology. The higher the capacitance of high voltage status and underground distribution, the more differential current includes the second harmonic component during occurrence of an internal fault. Therefore, the conventional harmonic restraint methods need modification. This paper proposes an advanced protective relaying algorithm by fluxt-differential current slope characteristic and trend of voltage and differential current. To evaluate the performance of proposed algorithm, we have made comparative studies of PDR fuzzy relaying, and DWT relaying. The paper is constructed power system model including power transformer, utilizing the WatATP99, and data collection is made through simulation of various internal faults and inrush. As the results of test. the new proposed algorithm was proven to be faster and more reliable.

Investigation of Wetting Characteristics of Polymer Surfaces according to Electron Beam Irradiation (고분자 표면의 전자빔 조사에 따른 젖음특성 고찰)

  • Lee, Hyun Joong;Park, Keun;Kim, Byung Nam
    • Journal of the Korean Society for Precision Engineering
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    • v.33 no.1
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    • pp.45-51
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    • 2016
  • The present study uses an electron beam (e-beam) to modify the wetting characteristics of thermoplastic polymer surfaces. A high energy e-beam irradiated various polymer surfaces (PET, PMMA, and PC), with variations in irradiation time and applied current. The water contact angles were measured on the e-beam irradiated surfaces in order to investigate the changes in the surface energy and the relevant wettability. Furthermore, XPS analyses were performed to investigate the chemical composition change in the e-beam irradiated surfaces; the results showed that the hydrophilic groups (C-O) increased after the electron beam irradiation. Also, water collection tests were performed for various polymer samples in order to investigate the effect of the surface energy on the ability of water collection, from which it can be seen that the irradiated surfaces revealed better water-collecting capability than pure polymer surfaces.

A Study on the Analysis of Circulation and Usage of Law Library Collection: A Case Study of Law Library in S University (법학도서관 장서의 대출현황 분석 및 이용에 관한 연구 - S 대학 법학도서관을 중심으로 -)

  • Ahn, Jooyeon;Kim, Seonghee
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.30 no.4
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    • pp.255-274
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    • 2019
  • In this study, we analyzed Circulation data of Law library in the S university for one year in 2018 and analyzed whether the Library holdings are actually used for education and research. First of all, this study analyzed user patterns by analyzing subjects, languages, and publication years for books that were circulated for one year from the ALMA system which is an S university library system. In addition, we analyzed how the current library holdings were used or cited in course syllabi and research papers written by members in S university. The results from this study can be used as an important basic data for effective collection development.