• Title/Summary/Keyword: 선형구조분석

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Shear behavior at the interface between particle and non-crushing surface by using PFC (PFC를 이용한 입자와 비파쇄 평면과의 접촉면에서의 전단 거동)

  • Kim, Eun-Kyung;Lee, Jeong-Hark;Lee, Seok-Won
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.14 no.4
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    • pp.293-308
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    • 2012
  • The shear behavior at the particle/surface interface such as rock joint can determine the mechanical behavior of whole structure. Therefore, a fundamental understanding of the mechanisms governing its behavior and accurately estimation of the interface strength is essential. In this paper, PFC, a numerical analysis program of discrete element method was used to investigate the effects of the surface roughness on interface strength. The surface roughness was characterized by smooth, intermediate, and rough surface, respectively. In order to investigate the effects of particle shape and crushing on particle/surface interface behavior, one ball, clump, and cluster models were created and their results were compared. The shape of particle was characterized by circle, triangle, square, and rectangle, respectively. The results showed that as the surface roughness increases, interface strength and friction angle increase and the void ratio increases. The one ball model with smooth surface shows lower interface strength and friction angle than the clump model with irregular surface. In addition, a cluster model has less interface strength and friction angle than the clump model. The failure envelope of the cluster model shows non-linear characteristic. From these findings, it is verified that the surface roughness and particle shape effect on the particle/surface interface shear behavior.

A Study of The Crystal-image in Yuri Norstein's Animated Film (유리 노르슈테인의 <이야기 속의 이야기>에 나타난 결정체-이미지 연구)

  • Kim, Hyun-Jeong
    • Cartoon and Animation Studies
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    • s.38
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    • pp.93-114
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    • 2015
  • In the history of animation, which created by Yuri Norstein is one of the best animations in the world. Out of all animations that Yuri Norstein created, is one animation that most people have hard time to understand because unexpected images and complicated structure of this animation get us confused. And also since this animation is based on Yuri Norstein's childhood memories and his own experiences, people who doesn't understand Russian culture and history will be lost. The purpose of this study is to analyze created by Yuri Norstein through the crystal-image in of Deleuze. According to Deleuze, we can see and understand unorganized time through the crystal-image which is the door way understanding and recognizing the time-image. In the there are some of the crystal-image appears. Eternity episode is one of the Crystal-images. In eternity episode we can see a peaceful life as simply continue endlessly. This is also the part that shows subject of animation and time itself accoding to Deleuze. By Yuri Norstein reflects Deleuze's claims that time-image we think and realize through crystal-image is eventually human life and universe.

RFID-Based Integrated Decision Making Framework for Resource Planning and Process Scheduling for a Pharmaceutical Intermediates Manufacturing Plant (의약품 중간체 생산 공정의 전사적 자원 관리 및 생산 계획 수립을 위한 최적 의사결정 시스템)

  • Jeong, Changjoo;Cho, Seolhee;Kim, Jiyong
    • Korean Chemical Engineering Research
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    • v.58 no.3
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    • pp.346-355
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    • 2020
  • This study proposed a new optimization-based decision model for an enterprise resource planning and production scheduling of a pharmaceutical intermediates manufacturing plant. To do this work, we first define the inflow and outflow information as well as the model structure, and develop an optimization model to minimize the production time (i.e., makespan) using a mixed integer linear programing (MILP). The unique feature of the proposed model is that the optimal process scheduling is established based on real-time resource logistics information using a radio frequency identification (RFID) technology, thereby theoretically requiring no material inventories. essential information for process operation, such as the required amount of raw materials and estimated arrival timing to manufacturing plant, is used as logistics constraints in the optimization model to yield the optimal manufacturing scheduling to satisfy final production demands. We illustrated the capability of the proposed decision model by applying the optimization model to two scheduling problems in a real pharmaceutical intermediates manufacturing process. As a result, the optimal production schedule and raw materials order timing were identified to minimize the makespan while satisfying all the product demands.

The ecological factors affecting walking in korean adult workers (한국 성인 직장인의 걷기에 영향을 미치는 생태학적 요인)

  • Kim, Myung-gwan;Suh, Soon-Rim
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.5
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    • pp.68-78
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    • 2017
  • The purpose of this study was to identify the influence of the individual-level and community-level factors in the ecological model on walking and to provide the basic data for a strategy that can increase walking for health promotion of adult workers. By combining the primary data of community health survey (CHS) (2011-2013) with the Korea national statistics annual book (2011-2013), the regional level variables were extracted from 253 municipal districts and the convergent big data with the hierarchical structure was produced. As a result, the increase in budget expenditure for public order and safety in social and cultural environment factors, the increase in budget expenditure for national and community land development in the leisure environment factors, and the number of buses in the transportation environment were increased by walking. In conclusion, walking was increased by the development of a community environment and bus transportation besides individual characteristics and behavior. Therefore, improving environment and public transportation will increase physical activity, such as walking, which will increase the health expectancy in community citizen workers.

Mechanical Characteristics of Basalt in Jeju Island with Relation to Porosity (공극률에 따른 제주도 현무암의 역학적 특성)

  • Moon, Kyoungtae;Park, Sangyeol;Kim, Youngchan;Yang, Soonbo
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.34 no.4
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    • pp.1215-1225
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    • 2014
  • Volcanic rocks formed from magma near the earth surface commonly show vesicular structures due to exsolution of gaseous phases in magma. The distinction and the amount of vesicles are greatly various, but there are few researches on the effect of volume percentage of vesicles on the mechanical properties. In this study, mechanical characteristics of volcanic rocks in relation to the porosity are investigated through experimental tests with Jeju basalt. Two methods (the buoyancy method and the caliper method) are adopted for measuring porosity. And unconfined compressive strength, elastic modulus, tensile strength, and elastic wave velocity are plotted against porosity in order to propose the empirical relations after the regression analysis. Also, unconfined compressive strength and the elastic modulus in relation to the elastic wave velocity are proposed with the analysis. In the case of vesicular rocks with more than 5% porosity, it is found that the buoyancy method provides more accurate estimation of porosity than the caliper method. The unconfined compressive strength, the elastic modulus, and the elastic wave velocity decrease curvilinearly with increasing in porosity. Also, the unconfined compressive strength and the elastic modulus increase linearly with increasing in elastic wave velocity.

Preparation and characterization of La0.8Sr0.2Ga0.8Mg0.1Co0.1O3-δ electrolyte using glycine-nitrate process (Glycine nitrate process로 합성된 La0.8Sr0.2Ga0.8Mg0.1Co0.1O3-δ 전해질의 제조 및 특성평가)

  • Ok, Kyung-Min;Kim, Kyeong-Lok;Kim, Tae-Wan;Kim, Dong-Hyun;Park, Hee-Dae;Sung, Youl-Moon;Park, Hong-Chae;Yoon, Seog-Young
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.23 no.1
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    • pp.37-43
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    • 2013
  • Conductivity of LSGMC materials were affected by secondary phase segregation, composition and synthetic route. $La_{0.8}Sr_{0.2}Ga_{0.8}Mg_{0.1}Co_{0.1}O_{3-{\delta}}$ (LSGMC) powders were prepared using the glycine nitrate process to produce high surface area and compositionally homogeneous powders. The powders were synthesized with different 0.5, 1, 1.5, 2, 2.5 of glycine/cation molar ratios. A single perovskite phase from the synthesized powders was characterized with X-ray diffraction patterns. The obtained sintered pellets showed the dense grain microstructure. In case of 1.5 molar ratio, its density was higher than the others. The electrical conductivity measured at $800^{\circ}C$ was observed to be 0.131 $Scm^{-1}$. In addition, the linear thermal expansion behavior was indicated between $25^{\circ}C$ and $800^{\circ}C$.

Behavior and Capacity of Compression Lap Splice in Confined Concrete with Compressive Strength of 40 and 60 MPa (횡보강근이 있는 40, 60 MPa 콘크리트에서 철근 압축이음의 거동과 강도)

  • Chun, Sung-Chul;Lee, Sung-Ho;Oh, Bo-Hwan
    • Journal of the Korea Concrete Institute
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    • v.21 no.4
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    • pp.389-400
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    • 2009
  • A compression lap splice can be calculated longer than a tension lap splice in high strength concrete according to current design codes. Including effects of transverse reinforcement, a compression splice becomes much longer than a tension splice. Effects of transverse reinforcement and bar size on strength and behavior of compression lap splice, which always exist in actual structures, have been investigated through experimental study of column tests with concrete strength of 40 and 60 MPa. The results of the tests with bar diameters of 22 and 29 mm show that there is no size effect of bar diameter on compression lap splice. Bond strength of small bar diameter may increase. However, large diameters of re-bars are used in compression member and the size effect of re-bars does not have to be considered in compression lap splice. Confined specimens have twice of calculated strengths by current design codes. New design equations for the compression lap splice including the effects of transverse reinforcement are required for practical purpose of ultra-high strength concrete. End bearing is enhanced by transverse reinforcement placed at ends of splice not by transverse reinforcement within splice length. As more transverse reinforcement are placed, the stresses developed by bond linearly increase. The transverse reinforcements at ends of splice a little improve the strength by bond. Because the stresses developed by bond in compression splice with transverse reinforcement are nearly identical to or less than those in tension splice with same transverse reinforcement, strength increment of compression splice is attributed to end bearing only.

Calculations of Flat Plate Deflections Considering Effects of Construction Loads and Cracking (시공하중 및 균열 효과를 고려한 플랫 플레이트의 처짐 산정)

  • Kim, Jae-Yo;Im, Ju-Hyeuk;Park, Hong-Gun
    • Journal of the Korea Concrete Institute
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    • v.21 no.6
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    • pp.797-804
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    • 2009
  • The structural designs of RC flat plates that have insufficient flexural stiffness due to lack of support from boundary beams may be governed by serviceability as well as a strength criteira. Specially, since over-loading and tensile cracking in early-aged slabs significantly increase the deflection of a flat plate system under construction, a construction sequence and its impact on the slab deflections may be decisive factors in designs of flat plate systems. In this study, the procedure of calculating slab deflections considering construction sequences and concrete cracking effects is proposed. The construction steps and the construction loads are defined by the simplified method, and then the slab moments, elastic deflections, and the effective moment of inertia are calculated in each construction step. The elastic deflections in column and middle strips are magnified to inelastic deflections by the effective moment of inertia, and the center deflection of slab are calculated by the crossing beam method. The proposed method is verified by comparisons with the existing test result and the nonlinear analysis result. Also, by applications of the proposed method, the effects of the slab construction cycle and the number of shored floors on the deflections of flat plates under construction are analyzed.

Professional Nursing Quality Assurance (전문직 간호의 질적보장)

  • Kim, Hea-Sook
    • Journal of Korean Academy of Nursing
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    • v.22 no.2
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    • pp.248-259
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    • 1992
  • 질적 보장은 전문직 종사자에 의하여 수혜받는 대상자를 보호하기 위하여 전적으로 필요한 프로그램이다. 이러한 질적보장을 통하여 전문직의 자율성과 책임을 튼튼히 할 수 있는 의무는 전문직 종사자 모두의 관심사가 되어야 한다. 미국에 있어서 질적 간호에 대한 관심은 이제 새로운 이유가 아니다. Beyers(1988)는 건강체계 지도자 사이에 가장 중요한 문제로 강조하는 것이 수혜자의 이용의 용이성(Access), 숫가(Cost) 그리고 질적인 제공(Quality)이 라고 피력 하였다. 미국 건강사업 평가자와 조정자(Regulator)들은 질(Quality)을 위한 자율적인 프로그램에 많은 에너지를 투입하여 전반적인 건강사업 즉 의료계의 질보장, 더 나아가서는 간호의 질을 향상 시키기 위한 많은 프로그램을 분석 연구한다. 이 논문은 간호에 있어서 질적 보장을 위한 내용으로 주요점은 질적 보장에 사용되는 용어, 역사적 배경, 질적 보장을 강조하는 이유, 질적 보장제도의 개발, 질 사정(euali assessment)과 질적 보장에 있어서 간호 전문직 개입을 차례대로 설명하였다. 구미의 경우 1970년대부터 간호직에 있어서는 질적보장제도개발에 우선순위를 두게되어 미 간호협회에서는 Professional Standards Review Organizations (PSRO)에 근거하여 간호실무를 위한 표준을 내어놓았다. 질적보장을 위한 평가방법으로 구조, 과정, 결과 그리고 수혜자가 간호계획을 세우는데 사정에 참여하는 방법 등 4가지를 간략하게 설명하였다. 질적 보장을 향상시키기 위해서는 전문직과 공공의료기간이 서로 협동체가 되어 중추역할을 해야함을 강조하고 이렇게 서로 협력하므로써만이 비로서 우리의 목적을 성취할 수 있다고 생각된다.구 등이 이용된다. $^{166}$ Ho, $^{198}$ Au, $^{32}$P, $^{90}$ Y, $^{169}$ Er, $^{186}$ Rc, $^{131}$ I, $^{211}$ At 등 의 방사성 핵종의 교질, 미소구 또는 단세포군 항체표지 형태로 직접 종양내 또는 공동이나 체강에 투여하는 치료법이 있다. 류마치스 관절염의 슬관절에 $^{165}$ Dy colloid를 주사하는 $^{166}$ Ho-MAA도 활발히 이용되고 있다. and computed groundwater levels. 본 논문에서는 가파른 산사면에서 산사태의 발생을 예측하기 위한 수문학적 인 지하수 흐름 모델을 개발하였다. 이 모델은 물리적인 개념에 기본하였으며, Lumped-parameter를 이용하였다. 개발된 지하수 흐름 모델은 두 모델을 조합하여 구성되어 있으며, 비포화대 흐름을 위해서는 수정된 abcd 모델을, 포화대 흐름에 대해서는 시간 지체 효과를 고려할 수 있는 선형 저수지 모델을 이용하였다. 지하수 흐름 모델은 토층의 두께, 산사면의 경사각, 포화투수계수, 잠재 증발산 량과 같은 불확실한 상수들과 a, b, c, 그리고 K와 같은 자유모델변수들을 가진다. 자유모델변수들은 유입-유출 자료들로부터 평가할 수 있으며, 이를 위해서 본 논문에서는 Gauss-Newton 방법을 이용한 Bard 알고리즘을 사용하였다. 서울 구로구 시흥동 산사태 발생 지역의 산사면에 대하여 개발된 모델을 적용하여 예제 해석을 수행함으로써, 지하수 흐름 모델이 산사태 발생

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Stiffness Reduction Factor for Post-Tensioned Flat Plate Slabs under Lateral Loads (횡하중하의 포스트 텐션 플랫 플레이트 해석을 위한 강성감소계수)

  • Park, Young-Mi;Park, Jin-Ah;Han, Sang-Whan
    • Journal of the Korea Concrete Institute
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    • v.21 no.5
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    • pp.661-668
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    • 2009
  • Effective beam width model(EBWM) has been used for analysis of post-tensioned(PT) flat plate slab frames under lateral loads. The accuracy of this model in predicting lateral drifts and unbalanced moments strongly depends on the estimated effective stiffness of PT flat plate slabs. As moments on the slab due to lateral loads increases, cracks occur which leads to stiffness reduction in slabs. For analyzing PT flat plate slab structure under lateral loads with good precision, reduction in slab stiffness has to be accurately estimated for EBWM. For this purpose, this study collected test results of PT flat plate system conducted by former researches. And this study reduced the width of slab so that the stiffness of the EBWM converged into the lateral stiffness of each test specimens by trial and error. By conducting nonlinear regression analysis using the stiffness ratio of the reduced width of slab to the effective width of EBWM with respect to the level of slab moments, an equation for calculating stiffness reduction factor for slab is proposed. For verifying the accuracy of the proposed equation, this study compared with the test result of the PT flat plate frame. It is shown that the EBWM with the proposed equation predicts the actual stiffness of the PT specimen which varied according to the level of applied moment.