• Title/Summary/Keyword: Korea Design Standard

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Insulation Design Standards for Protection of Power System against Lightning in Korea Electric Power Corporation (낙뢰로부터 전력설비 보호를 위한 한전의 절연설계 기준)

  • Woo, J.W.;Moon, J.D.
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.55 no.12
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    • pp.555-560
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    • 2006
  • As it has been reported that more than 60% of transmission line faults occurs due to lightning strokes, lighting is one of concerned issues in electric power utility company. Most of transmission line is double circuit in Korea. Double circuit outages account for 33.7 percent of total lightning faults from 1996 to 2004. Even though transmission fault might be cleared shortly by protective system, it could deteriorate the power quality accompanied with sag or flicker. Moreover, double circuit fault may lead to more aggravated situation, for instance, blackout. To Protect transmission lines from lightning stroke, reduction of tower footing resistance, multiple ground wires and unbalanced insulation in double circuit lines have been adopted. In this paper, we would like to introduce insulation design standards for lightning protection of Korea Electric Power Corporation.

A Design of Multiplication Unit of Elementary Mathematics Textbook by Making the Best Use of Diversity of Algorithm (알고리즘의 다양성을 활용한 두 자리 수 곱셈의 지도 방안과 그에 따른 초등학교 3학년 학생의 곱셈 알고리즘 이해 과정 분석)

  • Kang, Heung-Kyu;Sim, Sun-Young
    • Journal of Elementary Mathematics Education in Korea
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    • v.14 no.2
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    • pp.287-314
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    • 2010
  • The algorithm is a chain of mechanical procedures, capable of solving a problem. In modern mathematics educations, the teaching algorithm is performing an important role, even though contracted than in the past. The conspicuous characteristic of current elementary mathematics textbook's manner of manipulating multiplication algorithm is exceeding converge to 'standard algorithm.' But there are many algorithm other than standard algorithm in calculating multiplication, and this diversity is important with respect to didactical dimension. In this thesis, we have reconstructed the experimental learning and teaching plan of multiplication algorithm unit by making the best use of diversity of multiplication algorithm. It's core contents are as follows. Firstly, It handled various modified algorithms in addition to standard algorithm. Secondly, It did not order children to use standard algorithm exclusively, but encouraged children to select algorithm according to his interest. As stated above, we have performed teaching experiment which is ruled by new lesson design and analysed the effects of teaching experiment. Through this study, we obtained the following results and suggestions. Firstly, the experimental learning and teaching plan was effective on understanding of the place-value principle and the distributive law. The experimental group which was learned through various modified algorithm in addition to standard algorithm displayed higher degree of understanding than the control group. Secondly, as for computational ability, the experimental group did not show better achievement than the control group. It's cause is, in my guess, that we taught the children the various modified algorithm and allowed the children to select a algorithm by preference. The experimental group was more interested in diversity of algorithm and it's application itself than correct computation. Thirdly, the lattice method was not adopted in the majority of present mathematics school textbooks, but ranked high in the children's preference. I suggest that the mathematics school textbooks which will be developed henceforth should accept the lattice method.

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Object-oriented Road Field BIM Standard Object Classification System Suggest Development Plan (객체지향의 도로분야 BIM 표준객체분류체계 개발방안)

  • Nam, Jeong-Yong;Kim, Min-Jeong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.3
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    • pp.119-129
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    • 2018
  • The Ministry of Land, Transport and Maritime Affairs has promulgated the mandatory design of BIM for road projects of more than 50 billion won by 2020 under the Basic Plan for the Sixth Construction Technology Promotion. As a result, major public clients are attempting to implement BIMs that are appropriate to the situation of each institution. On the other hand, it is difficult to design and construct a proper BIM and accumulate BIM information of the ordering organization because the technical guidelines and standard classification system that can perform BIM effectively have not been presented sufficiently. The characteristics of the road should be managed systematically, e.g., atypical objects, such as earthworks, which are constantly changing along a line; large objects, such as bridges and tunnels; and facilities, such as signs and soundproof walls. To achieve this, a multitude of standard systems should be developed and disseminated, but there have been insufficient studies on practical methods. To solve this problem, this study developed a BIM standard object classification system in the road sector to meet the international standard, accommodate a multi-dimensional information system, and provide a more effective BIM standard information environment that can be utilized easily by practitioners.

Survey on Labeling of Health Functional Foods in Internet Shopping Malls

  • PARK, Sang-Kyu;UHM, Tai-Hwan
    • Journal of Distribution Science
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    • v.17 no.6
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    • pp.57-63
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    • 2019
  • Purpose - This research is to review the state of standard labeling compliance and identify the factors that are conducive to compliance with the Labeling Standards of the Health Functional Foods Act in internet distribution. Research design, data, and methodology - We checked 9 labels including product name, expiration date, manufacturing date, raw material, ingredient, operative dose, nutritional information, daily intake, and functional effect which are based on Labeling Standards of the Act from 100 health functional foods in the internet shopping malls. These 9 structure & function claims were compared using a Chi-square test. Results - There was a statistically significant difference in the use of standard labeling between domestic product and imported products (p<.001). The related strength between these two variables showed a moderate effect size. Also, there was a statistically significant difference between accredited advertising/unaccredited advertising distinction and use of standard labeling (p<.001). The related strength between these two variables showed a moderate effect size. Conclusions - The Labeling Standards of the Act were not followed and found to be related to imports or unauthorized advertising in internet distribution. The information displayed according to the Labeling Standards was only about 2 on the average, so many labels have been posted unreadably without arrangement.

A study on the recognition system design of one-time use of a standard plastic garbage bag at automaticat garbage facility (자동 쓰레기 집하 시설에 사용되는 1회사용 종량제 봉투 인식 장치 설계에 관한 연구)

  • Kim, Kea-Kook;Seo, Chang-Ok
    • Proceedings of the Korean Society of Computer Information Conference
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    • 2012.01a
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    • pp.41-43
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    • 2012
  • Today many people are greatly interested in the environment. Especially increasing affluent of food causes a great amount of food waste. To handle this effectively, we now have a lot of problems of disposing garbage all over the world. In Korea, in order to reduce this garbage, we should use a standard plastic garbage bag in which we have to throw away our garbage. So it has an effect on significantly reducing the waste amount every year. Now, there are a lot of cases that residents again use a standard plastic garbage bag. The purpose of this study is to propose algorithm preventing the re-cycling of a standard plastic garbage bag.

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The Determination of Optimal Steel Pipe Wall Thickness Considering Ground Condition (지반 조건을 고려한 최적강관두께의 결정)

  • Park, Jaesung;Oh, Bungdong;Lee, Hojin
    • Journal of the Korean GEO-environmental Society
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    • v.9 no.3
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    • pp.11-15
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    • 2008
  • By considering manufacture and economic factor, the steel pipes have been employed for water supply pipeline with large diameter. The standard to decide a thickness of pipe was provided by the waterworks standard (Ministry of Construction & Transportation, 1992) in South Korea. However, there was no the systematic standard to confirm a thickness of pipe in it. Thus, it should be able to apply to unsuitable the Stewart formula for the buried pipe to design for an optimum thickness of pipe. In order to meet revised the waterworks standard (The Ministry of Environment, 1997), it has been considered both the ground condition and all of the stresses to compute a thickness of pipe. As a results, a method is suggested to determine thickness of pipe after comparing and validating the obtained results with the established results from the Stewart formula.

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Development and Validation of Sky Simulator for Reproducing CIE Overcast Sky Model (돔형 인공천공의 개발 및 CIE표준담천공 구현 검증에 관한 연구)

  • Shin, Ju Young;Yun, Geun Young;Kim, Jeong Tai
    • KIEAE Journal
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    • v.10 no.6
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    • pp.97-103
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    • 2010
  • Sky simulator is a effective daylighting design tool that can evaluate three dimensional performance of lighting. Especially, the dome type sky simulator offer reliable and reproducible daylighting performance with different standard sky models. Recently, K university has developed the dome type sky simulator(sky dome) with the diameter of 6.5m and the height of 3.7m. The sky dome consists of a group of 145 large steel panels with 72 halogen lamps which are arranged in a circular array. The luminance distribution of the sky dome can be calibrated by changing the angle and the brightness of the lamps respectively. To allow more reliable prediction and evaluation of daylighting through the sky dome, It is essential to validate the sky luminance distribution of the sky dome. This study consider the validation of the comparisons between the measured and the calculated luminance values for the CIE standard overcast sky. Also, the error rate between the measured and the calculated luminance values were compared to the previous studies. The results indicated that the K university sky dome can reproduce reliable CIE standard overcast sky with the average relative error rate of 4.4% and root-mean-square error(RMSE) of 5.4%.

A Design and Implementation of Multimedia Contents Services System Using ZigBee in Ubiquitous Environment (유비쿼터스 환경에서 ZigBee를 이용한 멀티미디어 컨텐츠 서비스 시스템 설계 및 구현)

  • Kim, Min-Sung;Chung, Yeong-Jee
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2009.10a
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    • pp.1014-1017
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    • 2009
  • Ubiquitous makes it possible to expand a short-distant wireless communications infra and provide various services. Especially, it is very important to develop multimedia contents service technology through ZigBee and WPAN technology. But because the data transmission rate of IEEE 802.15.4 Standard ZigBee is low, there are many barriers for multimedia contents services. In this paper, to improve ZigBee that has the limitation of transmission rate in IEEE 802.15.4 Standard, an upgraded model to 1Mbps through MAC Layer remodeling is designed. And Zigbee-based broadcasting multimedia contents services system is designed and implementation to provide the service in Ubiquitous environment.

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Optimum Design of the Cylindrical Shell under External Pressuer Loading (수압을 받는 원통형 쉘의 최적설계)

  • 임오강;이병우;전완수;정현기
    • Computational Structural Engineering
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    • v.8 no.1
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    • pp.85-94
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    • 1995
  • The optimum design of the cylindrical shell under external pressure loading is considered. The design variable is a skin thickness of the unstiffened parallel middle body shell. Overall buckling strength and direct stress and displacements constraints are considered in the design problem The optimum design is achieved with one of the standard nonlinear constrained optimization technique. A method for calculating the sensitivity coefficients is developed using the direct differentiation.

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Economic Evaluation Method by Design Method ASD and LRFD of Aluminum Curtain wall (알루미늄 커튼월의 ASD/LRFD설계방법에 따른 경제성 평가 방법)

  • Moon, Sang-Deok;Ock, Jong-Ho
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2014.05a
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    • pp.16-17
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    • 2014
  • The curtain wall construction applied on high-rise building facades in Korea became generalized, but specialty of the CMr(Construction Manager) who needs to perform economical project management with specialty in the curtain wall construction is still lacking. Therefore, this study analyzed the structure design standard of the curtain wall, researched economical design alternatives. Based on the research results, if the ratio of dead load against wind load is less than 0.1256, LRFD will be more economical.

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