• Title/Summary/Keyword: 여유 강도

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A Study of Water Transfer between Han River and Nakdong River Basins (한강-낙동강 유역간 물이동 분석)

    • Journal of Korea Water Resources Association
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    • v.31 no.4
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    • pp.483-490
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    • 1998
  • The possibility of water transfer from Han river basin to Nakdong river basin by connecting them is studied as an alternative to solve water shortage problem in Nakdong river basin. After estimating the amount of water shortage from Nakdong river basin, the amount of water surplus from Han river basin is estimated by using simulation and optimization techniques. HEC-5 is used to study small to medium size reservoirs as a simulation technique and dynamic programming is used to study multi-purpose reserviors as an optimization technique. Also, the cost of the interbasin water transfer from Han river basin to Nakdong river basin is also compared with that of constructing new reserviors in Nakdong river basin. If new reservoirs are constructed in Nakdong river basin as planned, water supply can satisfy various water demands until 2021 without the interbasin water transfer. In economic point of view, constructing new reserviors has an advantage over the interbasin water transfer.

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Fault-tree based reliability analysis for paralleled half-bridge sub-module of HVDC (HVDC 병렬 하프브리지 서브모듈에 대한 고장나무기반의 신뢰성 분석)

  • Kang, Feel-soon;Song, Sung-Geun
    • Journal of IKEEE
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    • v.23 no.4
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    • pp.1218-1223
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    • 2019
  • In HVDC systems, the full-bridge submodule increases the number of components compared to the half-bridge submodule, but the failure-rate can be reduced by securing 100 % redundancy. However, full-bridge submodules require more complex control algorithms to ensure the redundancy and to prevent arm-short with sufficient dead-time. To solve this problem, we analyse the failure-rate of the paralleled half-bridge configuration with the same number of components and 100 % redundancy as the full-bridge submodule. The fault tree analysis (FTA) method is applied to the conventional part failure analysis to reflect the operation risk of the submodule, thereby predicting the life-cycle of the submodule more accurately. To verify the validity, the failure-rate results of the proposed FTA based analysis method are compared with the failure rate obtained by the part failure method.

The Biaxial Flexure Test(BFT) method and its finite element analysis (이방향 휨인장 시험(Biaxial Flexure Test; BFT) 및 삼차원 유한요소 해석)

  • Kim, Ji-Hwan;Zi, Goang-Seup;Kang, Jin-Gu;Oh, Hong-Seob
    • Proceedings of the Korea Concrete Institute Conference
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    • 2008.04a
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    • pp.693-696
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    • 2008
  • The biaxial tensile strength of concretes was measured by the Biaxial Flexure Test(BFT) which was recently developed to measure the biaxial tensile strength of concretes. From the test result, The circular specimen is generally fractured after 1${\sim}$3 of the initial crack were formed on the top of specimen. The direction and number of the initial crack was completely arbitrary. As the specimen was larger, the number of the crack increased. And, the strengths of the different radii and thickness of specimens were calculated by the commercial finite element program to study the size effect of the biaxial tensile strength like the uniaxial tensile strength. The parameters such as radii to the support and to the load point, were studied using the program. The results of the FE analysis were entirely consistent with the predictive solution, when b/a>0.4, and the thickness of the specimens were increased. On the other hands, those with lesser free length showed good results.

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A Study on the Establishment of Hydrological Safety Evaluation System Considering the Climate Change Effects Factors (기후변화에 따른 기후영향인자를 고려한 수문학적 안전성 평가 체계 구축에 관한 연구)

  • park, Jiyeon;Jung, ilwon;Kim, Mina;Kwon, Jihye
    • Proceedings of the Korea Water Resources Association Conference
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    • 2018.05a
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    • pp.460-460
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    • 2018
  • 댐 수문학적 안전성평가는 "시설물의 안전 및 유지관리에 관한 특별벌(이하 시특법)"에 따른 댐시설물의 정밀안전진단의 안전성평가 중 가장 중요한 평가 항목으로 댐 시설물을 평가 수행 시 주요한 평가 항목이다. 기존의 수문학적 안전성평가는 가능최대강수량 발생 시 댐의 월류 및 여유고 확보여부에 대한 평가 여부만 판단하고 있으나, 본 연구에서는 기후변화를 고려하는 장기적 관점의 추가 평가항목을 도출하고자 한다. 현재 가능최대강수량으로 event적 평가를 수행하는 수문학적 안전성 평가에서 기존평가항목 뿐만 아니라, 기후변화 장기적 관점의 추가적인 기후영향인자를 도출하고 이를 함께 적용할 수 있는 평가 체계를 구축하고자한다. 장기적 관점의 기후영향인자라 함은 기상청에서 제공하는 기후변화 시나리오 결과에서 30년동안 장기적인 관점에서 대상 댐의 운영에 부담을 야기할 것으로 판단되는 인자를 말하는 것이며, 이때 기후변화 시나리오의 일자료를 활용하여 기후인자의 장기적 변동성을 추정하고자 하며, 이때 활용한 지표로는 월최대강수량, 연강우강도 및 댐 상태에 영향을 미칠 수 있는 최소기온을 사용하였다. 기후변화 시나리오의 불확실성을 최소화하기 위하여 월최대 강수량값을 산출하였고, 1년 동안 발생한 강우의 일수 및 강수량에 대한 영향을 고려하기 위하여 연강우강도값을 산출하였다. 또한 댐의 월류 및 여유고 확보여부 평가 시 댐 상태에 대하여 고려하기 때문에 댐의 외부상태에 영향을 주는 최소기온을 활용하여 댐별 평가를 수행하였다. 이때 2011~2040년(S1), 2041년~2070년(S2), 2071년~2100년(S3)기간으로 나누어 장기간 기후에 대한 영향 평가를 수행하여 1종 댐 시설물의 기후영향인자 값을 도출하였다. 도출된 기후영향인자를 기존 수문학적 안전성평가 항목과 함께 평가 될 수 있도록 AHP분석기법을 활용하여 각 인자에 대한 가중치를 재산출하였고, 기후영향인자를 고려하는 수문학적 안전성평가 체계를 구축하였다.

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An Analysis of The Preferred Ease of Torso Sloper by Body Size (신체크기에 따른 토르소원형의 부위별 선호여유량 분석)

  • Kang, Yeo-Sun
    • Journal of the Korean Society of Clothing and Textiles
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    • v.36 no.1
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    • pp.112-125
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    • 2012
  • This study researches the preferred ease of torso sloper according to body sizes and drop. For this, the eases of main body parts such as chest circumference, waist circumference, hip circumference, biacromion length, and waist back length were analysed; in addition, the drop differences of body and pattern were explored to find out characteristics of silhouette changes. The subjects were 55 women in their early 20s (aged from 20 to 24) and individual torso block made with muslin was corrected 1-3 times by a personal fitting. There were 3 meaningful results. First, the preferred ease were individually various; however, the eases of all torso blocks should be same at the pattern making step. Second, the eases were also significantly different among body size groups and the bigger group preferred less ease at the biacromion length, waist back length, armhole-depth, chest circumference, and waist circumference. Third, the eases of chest circumference and hip circumference were significantly changed among drop groups. To change their body drop, H-shape drop adopted less ease at chest circumference and more ease at hip circumference; however, A-shape drop adopted more ease at chest circumference and less ease at hip circumference.

The Research on the Woman's T-shirts focused on Purchasing Patterns and Ease (성인여성의 티셔츠 구입특성 및 여유량 조사연구)

  • Kang, Yeo-Sun
    • Korean Journal of Human Ecology
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    • v.20 no.1
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    • pp.169-182
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    • 2011
  • The purpose of this study was to research the purchasing patterns and the ease amount of woman's T-shirts. For the study, 215 women between the ages of 18 and 59 were surveyed. 18~34 year old women had more T-shirts and wore them more frequently than 35~59 year old women. Women usually gave weight to design, fabric, fit and color, when they bought T-shirts. The most important fit part was different according to age groups, 18~34 women valued T-shirts length but 35~59 women valued bust circumference ease. The ease of T-shirts was analysed with body sizes. Shoulder ease were distributed between -3~3cm, neckline designed apart 0.5~7.0cm from side neck point, 0~11cm from front neck point and 1~2cm from back neck point. The means of bust ease, waist ease and hip ease were 6.2cm, 14.7cm and 4.5cm. The bust and waist ease were significantly different between age groups and 35~59 year old women wore more tightly at both parts due to their thick torso. Women accepted smaller ease at hip while didn't want small ease at waist. The eases of shoulder, bust and T-shirts length were the most important and influencing.

Characteristics to ensure Optimum Ease in Men's Business Jackets (남성복 재킷의 선호 여유량과 맞음새에 관한 연구)

  • Kang Yeosun;Choi Hei-Sun
    • Journal of the Korean Society of Clothing and Textiles
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    • v.29 no.1 s.139
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    • pp.91-102
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    • 2005
  • The purpose of this study was to investigate the range of variation for commonly accepted ease in a business jacket and thus to find solutions to the problem of fit and ease in ready-to-wear jackets. This study was based on anthropometric measurements, pattern measurements, which were used to calculate ease amount according to each jacket part. The survey subjects were 493 males, between 25 to 59 years old, buying a jacket at stores in Seoul. In the results, the aesthetic purpose of a business jacket(custom-fit jacket) was clearly observed by the means of controlling the ease amount at chest, waist and hip. The ease at chest and waist(ready-to-wear) clearly revealed a difference among prototypes. This result can be explaned by the regular drops and the similar length-width proportions between sizes in ready-to-wear Jackets. Therefore, customers with varying body drop differences, who had to choose a homogeneous jacket drop, experienced too much ease at the Waist and Hip compared with custom-fit customers. In addition, the height could be an integral factor to affect the ease of jacket length and sleeve length. The ease at these parts was significantly different among height groups and showed negative relationships.

Lightning overvoltage analysis of 400kV separated GIS for BIL selection (400 kV급 상분리형 GIS의 기기 BIL 산정을 위한 뇌과전압해석)

  • Kang, Y.W.;Kwak, J.S.;Ju, H.J.;Kwan, D.J.;Shim, E.B.
    • Proceedings of the KIEE Conference
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    • 2005.07a
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    • pp.323-325
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    • 2005
  • 경제성장에 따른 인구의 집중화 및 도시기능의 고도화에 따라 전력기술분야의 많은 변화를 요구하게 되었다. 좁은 지역에 대용량의 전력을 안정적으로 공급하면서 환경과의 조화를 이루기 위하여 SF6개스를 이용한 개스절연개폐기(GIS)의 이용이 증가하였다. 이 논문에서는 중동국가에서 많이 건설되고있는 400kV 개스절연 변전소의 절연협조를 위하여 일반적으로 변전소 뇌과전압에 영향을 미치는 요소인 모선형태 및 구성, 피뢰기의 위치와 설치대수, 피뢰기의 제한 전압-전류특성, 모선의 길이, 피뢰기와 피보호기간의 이격거리 등을 고려하여 뇌침입시 변전소의 뇌과전압을 EMTP로 모의하여 개스절연변전소의 기기 절연강도를 결정하였다. 결정된 절연강도는 위의 모의결과로 얻어지는 발생예상 전압에 적정한 여유를 두고 IEC규격을 따라 선정하였다.

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웅묘에 있어서 포피점막을 이용한 회음요도루 조성술

  • 산촌수적;조준행
    • Journal of the korean veterinary medical association
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    • v.22 no.2
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    • pp.86-90
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    • 1986
  • 웅묘의 요도폐색의 외과적 치료법으로는 1971년 이후 Wilson의 회음요도루 조성술이 널리 사용되고 있다. Wilson법에선 요도와 피부를 직접봉합하나, 신축성이 없는 피부가 골반강방향으로 잡아 당겨져서 요도개구부가 좁아지기 쉽고 또 환축이 수술부위를 자주 핥으므로 봉합한 곳이 풀려지기도 하고 또 오줌에 의한 피부염이 일어나기 쉬운 결점 등이 있다. 그러나 이번 실험한 술기은 피부로부터 포피점막, 요도점막으로 이행시키기 때문에 피부가 요도구쪽으로 늘어나 이것이 작아질 염려가 전혀 없고. 오줌에 의한 피부염도 잘 일어나지 않는 이점이 있었다. 이것은 포피점막에는 신축성이 있고 그것이 양적으로 여유가 있기 때문에 더욱 요도가 수술후 골반강방향으로 매몰되기 때문에 봉합부를 환축이 혀로 핥을 수 없는 점은 대단히 이롭다.

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A Solution to the Inverse Kinematic by Using Neural Network (신경 회로망을 사용한 역운동학 해)

  • 안덕환;양태규;이상효
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.15 no.4
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    • pp.295-300
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    • 1990
  • Inverse kinematic problem is a crucial point for robot manipulator control. In this paper, to implement the Jacobian control technique we used the Hopfield, Tank's neural network. The states of neurons represent joint velocities, and the connection weights are determined from the current value of the Jacobian matirx. The network energy function is constructed so that its minimum corresponds to the minimum least square error. At each sampling time, connection weights and neuron states are updated according to current joint positon. Inverse kinematic solution to the planar redundant manipulator is solved by computer simulation.

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