• Title/Summary/Keyword: 순간성

Search Result 805, Processing Time 0.025 seconds

Dynamic Responses on Semi-Infinite Space Due to Transient Line Source in Orthotropic Media (선형하중에 의한 직교이방성 매체의 반구계에서 동적 응답 특성)

    • Journal of KSNVE
    • /
    • v.8 no.5
    • /
    • pp.974-980
    • /
    • 1998
  • The analysis of dynamic responses are carried out on several orthotropic systems due to transient line source. These include infinite and semi-infinite spaces. The media possess orthotropic or higher symmetry. The lode is in the form of a normal stress acting with parallel to symmetry axis on the plane of symmetry within the materials. The results are first derived for responses of infinite media due to a harmonic line source. Subsequently the results for semi-infinite are derived by using superposition of the solution in the infinite medium together with a scattered solution from the boundaries. The sum of both solutions has to satisfy stress free boundary conditions thereby leading to the complete solutions. Explicit splutions for the displacements due to transient line loads are then obtaind by using Cargniard-DeHoop contour.

  • PDF

일본석유산업의 국제화와 정책방향

  • Korea Petroleum Association
    • Korea Petroleum Association Journal
    • /
    • no.10 s.56
    • /
    • pp.13-21
    • /
    • 1985
  • 이 글은 일본통산성 자원에너지청의 자문기관인 석유번의회의 석유부회소위원회가 지난 9월 12일 발표한 중간보고서로서 일본순간 「석유정책 」지(85. 9. 15자)에 실린 것을 번역한 것이다. <편집자>

  • PDF

사고 사례 - 방직공장 화재사례

  • Kim, In-Tae
    • 방재와보험
    • /
    • s.111
    • /
    • pp.58-61
    • /
    • 2006
  • 방직 공장은 섬유의 착화 용이성, 원료의 밀집도, 연속공정으로 발화순간 전체 공정으로 연소가 확대되기 쉬우며, 착화되면 다량의 연기와 유독가스를 발생하기 때문에 항상 화재에 대한 각별한 주의가 요구되는 곳이다. 공장 화재 사례를 통해 문제점 및 각종 대책에 대해 알아보자.

  • PDF

A Case Study on Learning of Fundamental Idea of Calculus in Constant Acceleration Movement (등가속도 운동에서 미적분의 기본 아이디어 학습 과정에 관한 사례연구)

  • Shin Eun-Ju
    • Journal of Educational Research in Mathematics
    • /
    • v.16 no.1
    • /
    • pp.59-78
    • /
    • 2006
  • As a theoretical background for this research, the literatures which focus on the rationale of teaching and learning of connecting with mathematics and science in calculus were investigated. And teaching and learning material of connecting with mathematics and science in calculus was developed. And then, based on the case study using this material, the research questions were analyzed in depth. Students could understand mean-velocity, instant-velocity, and acceleration in the experimenting process of constant acceleration movement. Also Students could understand fundamental ideas that instant-velocity means slope of the tangent line at one point on the time-displacement graph and rate of distance change means rate of area change under a time-velocity graph.

  • PDF

Analysis of Transient Characteristics for Distributed Generations with the Secondary Feeders (저압배전선로에 연계된 분산전원의 과도특성 해석에 관한 연구)

  • Yoon, Gi-Gab;Rho, Dae-Seok;Kim, Eui-Hwan
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.11 no.10
    • /
    • pp.3898-3904
    • /
    • 2010
  • In order to analyze the transient characteristics for distributed generation located with the secondary feeders, this paper constructs a Distributed Generations Filed Test Center which can produce transient characteristics such as voltage sag, swell, interruption, harmonic and so on. And also this paper proposes the test results for the interconnection of distributed generations. The results show the effectiveness for the utility technical guidelines for distributed generations with the secondary feeders.

순간 동적 사용자 최적 통행배정모형을 이용한 교차로에서 좌회전 금지 효과분석

  • 김점산
    • Proceedings of the KOR-KST Conference
    • /
    • 1998.10a
    • /
    • pp.245-251
    • /
    • 1998
  • 좌회전 제어네는 크게 좌회전을 금지하는 적극적인 제어에서 좌회전 신호와 좌회전 차선의 디자인 및 차선 설정과 같은 비교적 소극적인 제어가 있다. 기존의 좌회전에 관한 많은 연구는 대부분 후자의 소극적인 제어를 통한 제어효과를 파악하는데 주로 관심을 두었다. 좌회전금지의 효과분석 방법론에는 크게 교차로 및 링크(Link)와 네트워크(Network)의 두가지 차원의 접근 방법이 있다. 교차로 및 링크(Link) 차원의 분석은 TRANSYT 7F, PASSER IV 등과 같은 가로망에서 신호시간을 최적화하는 모형과 NETSIM, COSIM과 같이 조건에 따라 실제 차량의 행태를 모사하는 시뮬레이션 모형 등에서 좌회전 신호현시를 주거나, 주지 않음으로써 전후의 변화를 관찰, 분석에 이용할 수 있다. 그러나, 이러한 접근방법은 개별교차로에서 현시운영에 따른 효과를 분석하기에는 용이할 지 모르나, 좌회전 금지에 따라 전환된 교통량을 합리적으로 처리하는데 문제를 가지고 있다. 이에 반해 네트워크(Network) 차원의 분석은 좌회전 금지에 따른 거시적 수요변화를 파악하여, 좌회전금지에 따라 전환된 교통량을 합리적으로 수용 할 수 있으며, 교차로 및 링크(Link) 차원의 분석기법과의 결합을 통해 개별교차로에서 현시운영에 따른 효과도 어느정도 예견할 수 있을 것으로 예상되지만, 이에 관련한 여구가 전무한 형편이다. 본 연구의 목적은 네트워크(Network) 차원에서 좌회전 금지에 따른 효과 분석 모형을 정립하고, 가상 네트워크에 적용 그 유효성을 검증하여, 지역 네트워크의 개별교차로에서 좌회전 금지의 도입에 대한 의사결정의 기준을 마련하는데 있으며, 이를 위한 구체적 연구 내용은 다름과 같다. 첫째, 순간 동작 사용자 최적 통행배정모형의 구조 및 특성 파악. 둘째, 기존 가로망 표현기법의 구조 및 특성파악. 셋째, 좌회전 금지에 따른 효과 분석을 위한 순간 동적 사용자 최적 통행배정모형의 구축. 넷째, 좌회전 금지에 따른 효과 분석을 위한 가로망 표현기법의 개발. 다섯째, 가상 네트워크에서 구축된 모형을 통한 교차로에서 좌회전 금지 효과분석

  • PDF

Effects of the Addition of Starch, Salt and Soda Ash on the Mechanical Property of Naengmyon (전분, 식염 및 알카리 첨가제가 냉면의 기계적 성질에 미치는 영향)

  • Kwon, O-Hun;Lee, Cherl-Ho
    • Korean Journal of Food Science and Technology
    • /
    • v.16 no.2
    • /
    • pp.175-178
    • /
    • 1984
  • The effects of the addition of starch, salt and soda ash to the dough for Naengmyon (wheat-sweet potato starch) on the mechanical property of Naengmyon noodle were evaluated by using creep test. The strain measurement was made by taking photograph with VTR system. The creep curve of noodle strand could be fitted to the 4 element Burgers model. The instantaneous elasticity and Newtonian viscosity of the noodle strand decreased by the addition of starch. The instantaneous elasticity decreased by the addition of salt up to 4%. The mechamical parameters of the noodle varied inconsistently by the addition of soda ash.

  • PDF

A Method of Estimating Radionuclide Accumulation in Coolant Purification System (원자력발전소 냉각수 정화계통의 핵종누적량 예측기법)

  • Whang, Joo-Ho;Lee, Jae-Min
    • Journal of Radiation Protection and Research
    • /
    • v.22 no.3
    • /
    • pp.183-193
    • /
    • 1997
  • The amount and kinds of radionuclide contained in waste volume should be known to prepare for occupational exposure management, perform safety assessment and finally to license a repository. Although the volume of filters and resins are small, activities of them comprise most of the radioactivity that made during power generation. This study aims at developing a method of estimating the radionuclide accumulation at the filters and resins of coolant systems. In this study, accumulated amount of radionuclides is estimated by a computer program which makes use of instantaneous decontamination factor, DF, instead of average DF. A FORTRAN program was developed for the estimation. Data from in-plant source-term measurements at Rancho-Seco nuclear power plant in the United States are employed for verification of the estimating method. And experimental data are employed, too. The instantaneous-DF-method showed smaller error than the average-DF-method. Accumulated amount of radionuclides can be calculated with only the DF and the radionuclide concentration, which are measured periodically according to the operating guide. However, especially, when the operating condition of nuclear power plant changes rapidly, the measuring term of DF and radionuclide should be shortened to ensure the accurate estimation.

  • PDF

Consideration of Bentonite Cake Existing on Vertical Cutoff Wall in Slug Test Analysis (벤토나이트 케익을 고려한 연직차수벽의 순간변위시험(slug test) 해석)

  • Lim, Jeehee;Nguyen, The-Bao;Lee, Dongseop;Ahn, Jaeyoon;Choi, Hangseok
    • Journal of the Korean Geotechnical Society
    • /
    • v.29 no.6
    • /
    • pp.5-17
    • /
    • 2013
  • Slug tests can be adopted to estimate hydraulic conductivity of the slurry trench wall backfill for its abilities to reflect the in-situ performance of the construction. A comprehensive three-dimensional numerical model is developed to simulate the slug test in a slurry trench wall considering the presence of bentonite cake on the interface boundaries between the wall and the surrounding soil formation. Influential factors such as wall width (i.e., proximity of wall boundary), well deviation, vertical position of well intake section, compressibility of wall backfill, etc. are taken into account in the model. A series of simulation results are examined to evaluate the bentonite cake effect in analyzing practical slug test results in the slurry trench wall. The results show that the modified line-fitting method can be used without any correction factor for the slug test in the slurry trench wall with the presence of bentonite cake. A case study is reanalyzed with the assumption of existing bentonite cake. The results are compared with the previously reported results by the approaches assuming no bentonite cake (constant-head boundary) or upper-bound solution (no-flux boundary). The case study demonstrates the bentonite cake effect and the validity of the modified line-fitting method in the estimation of the hydraulic conductivity of the slurry wall backfill.