• Title/Summary/Keyword: restraining

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Aseismatic Retrofit of Concrete Piers with Restraining Steel Ring and Expansive Concrete (구속강판과 팽창콘크리트를 이용한 기존 RC 교각의 내진 보강)

  • 최익창;박홍용;연준희;김연수
    • Proceedings of the Korea Concrete Institute Conference
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    • 2001.11a
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    • pp.953-958
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    • 2001
  • A retrofit method “Steel Ring Confinement Retrofit” was proposed and discussed on the material and member characteristics through experiments. Steel Ring Confinement Retrofit consist of confining steel ring and expansive concrete. The steel ring is set on the footing, surrounding the base of the pier. By placing expansive concrete between the pier and steel ring, chemical prestress is introduced in the members. Chemical prestressed ring concrete enlarge the pier section and enhance both the strength and ductility of the pier. It was confirmed that Various Ring Confinement Retrofit improved the strength of the pier up to 30% ~ 100% with experiments.

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Preferred Skin Color Reproduction of Digital Image by Ink-jet Printer (잉크젯 프린터에 의한 디지탈 이미지의 바람직한 피부 색재현)

  • 서봉우
    • Journal of the Korean Graphic Arts Communication Society
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    • v.14 no.2
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    • pp.37-49
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    • 1996
  • The practical lith developer is a hydroquinone solution of moderate alkalinity and low free-sulfite ion concentration with potassium bromide as the restraining agent. In the study on composition of ilth developer to promote high sensitivity, high contrast and long term preservation or use, a new composition of lith developer, namely PK lith developer, was developed and of was found that PK lith developer was superior to the lith developer which was commercially available in terms of contrast, speed and preservation. This paper also describes studies on the addition of hdydrazine to PK lith developer, which have led to further improvements in the system.

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Soil-Reinforcement Interaction to Restrain Differential Settlement of Buried Pipeline (지반-보강재 상호작용에 의한 매설관의 부등침하 억제효과)

  • 손준익;정하익
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1991.04a
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    • pp.29-33
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    • 1991
  • This paper reports the application study of the ground reinforement under a buried pipeline subjected to differential settlement via a finite element modelling. The Soil-reinforrement interaction helps to mimimize the differential settlement between the adjoining pipe segments. The settlement pattern and deformation slope of a pipeline have been evaluated for a boundary condition at the joint between a rigid structure and apipeline. The analysis results are compared for both non-reinforied and reinforced cases to measure the effectiveness of the soil reinforcement for restraining the settlement of the pipeline.

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Damping Characteristics of Impact Damper (충격식 감쇠기의 감쇠특성에 관한 연구)

  • 김원철;전순기;양보석;문덕호
    • Journal of KSNVE
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    • v.3 no.1
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    • pp.29-37
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    • 1993
  • This study is concerned about the impact type damper for effectively restraining the high vibration amplitude in the resonance regions. The theoretical analysis is based on the assumption that the impacts occur twice per cycle at an equal time interval. Simple but reasonable approximations have been derived for the optimum collision clearance and maximum amplitude ratio. Using the impact dampers which is rigidly attached to the primary vibration system, we have experimented for mass ratios and restitution coefficients. The experimental results are in good agreement with theoretical results.

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Development of Drawbead Expert Models for Finite Element Analysis of Sheet Metal Forming Process (Part1: Experiment) (박판성형공정의 유한요소해석을 위한 드로우비드 전문모델 개발 (1부: 실험))

  • 금영탁;이재우;박승우
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 1997.03a
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    • pp.46-49
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    • 1997
  • During sheet metal forming on a double-action press, drawbeads on the blankholder supply a restraining force which controls the flow of metal into the die. The sheet formability can be improved by the optimum drawbeads installation when the punch enters into the die opening. Experiments on the various drawbeads, circular, step, double circular, and circular-step drawbead, have been performed under various working conditions.

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The Efficient Berms for Restraining Excessive Deformation Caused by Deep Excavations in Urban Area (도심지 버팀 굴착시 과도 변헝 억제를 위한 효율적 소단)

  • 양구승;박기태
    • Journal of the Korean Geotechnical Society
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    • v.15 no.4
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    • pp.43-56
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    • 1999
  • The use of berms can be an effective method to restrain excessive movements of wall and ground caused by deep excavations in urban area. But generally in construction sites, no berm remains for the sake of construction convenience or the geometry and magnitude of remaining berm is determined by individual experiences due to scarce research results. In this research, laboratory model tests and numerical analyses are used mainly for sandy soils. And efficient berms for restraining excessive movements by deep excavations are analyzed. Model tests were performed for the cases of cantilever and braced wall excavations, and the behaviors of retaining wall were analyzed according to the geometry and magnitude of berms. And also, numerical methods were used for analyzing efficient berms which are available in the soil and construction conditions in urban areas of Korea.

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A Study of the Efficacy to Control the Bacteria Colony of Scalp in Ayurvedic Oils on Clinical Testing

  • Choi, Jung-Myung
    • Journal of Fashion Business
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    • v.13 no.6
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    • pp.45-60
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    • 2009
  • This study examined the efficacy of restraining the increase of the bacteria colony of scalp according to the application of the Ayurvedic base oils and essential oils to scalp and hair. The result is as follows. The experiment illustrated that as the result of doing the paired sample t-test of a treated group and a control group according to constitutional oiling, the efficacy of the statistically significant decrease of the colony manifested in six tested groups except the group of Pitta constitution to which sesame and lavender were applied. Also, in a group that sesame was applied to Vata constitution and a group that coconut and lavender were applied to Pitta constitution, according to the passage of time, the result of being reduced the number of the colony was obtained and it showed that the oiling suitable for each constitution has the efficacy to decrease the colony of scalp. At the same time, regardless of the constitutions, the application of oils also showed the efficacy of restraining the increase of the bacteria colony of scalp. As the result of performing Paired Sample t-test for the subjective evaluation of the subjects in pre and post clinical testing, In the analysis of questionnaire that were obtained before and after the clinical testing, the results of all of the items except the item questioning a degree of inflammation appeared to be significant. That is to say, the subjects answered that a degree of keratin or a pain in scalp, an amount of sebum and a degree of hair damage were decreased after the application of oil more than before it. And in the question of a degree of hair damage, the application of oils were proved as having the efficacy to improve the hair damage.

Forces and Displacements of Outrigger-Braced Structures with a Pair of Coupled Cores (병렬코아를 갖는 아웃리거구조물의 응력과 변위)

  • 정동조;이태희
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.16 no.3
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    • pp.291-299
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    • 2003
  • Based on the continuum approach, an investigation is made to get the forces and displacements of laterally loaded outrigger braced structures with a pair of coupled cores, and to show the effect of stiffening outriggers on the behavior of the structure. From the condition that the rotation of the core at the outrigger level is matched with the rotation of the corresponding outrigger, the outrigger restraining moment is derived analytically. From this, the core moment diagram, the column axial forces, and the horizontal displacements of the structure may be determined. Comparisons with the results by the program MIDAS-GEN for the structural models, have shown that this analysis can give reasonably accurate results for outrigger-braced structures with a pair of coupled cores. And a lateral displacement at the top of the structure is influenced by the outrigger location than the core location. Although the formulae are accurate only for idealized outrigger braced structures, they have a useful practical purpose in providing a guide to the behavior, and for making approximate estimates of the forces and displacements, in practical outrigger braced structures with a pair of coupled cores.

Analysis on Image Types and Design Element Qualities of Contemporary Black Make-up (블랙 컬러를 활용한 메이크업의 이미지 유형별 디자인 요소 특징)

  • Kim, Seol-Lee;O, In-Young
    • The Research Journal of the Costume Culture
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    • v.17 no.4
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    • pp.561-574
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    • 2009
  • Black has been the most important color of all since the ancient times when the recognition of black roused, as well as during most of the eras; and can especially be said as the main color which controlled the chronicles of fashion. The purpose of the study was to broaden the application of black color image make-up by inquiring into make-up design elemental characteristics of lines and textures, after classifying magazine illustrations and advertisement make-up images using black. The photos which made effective use of black among fashion illustrations, magazine advertisements after 2001 were classified in to each type, and make-up expression method and characteristics according to design element of each image type was analyzed. The conclusion of such study was the following. 'Erotic image' showed contrast effect between eye make-up and lip color by using pale tone or red color. 'Mannish image' emphasized form and texture of eyebrow by restraining the colors of eyelids with natural brown tone eye make-up; 'Modern image' expressed vague eyebrow to bring the sensation of the direction of eye shadow on eyelids and eye line as well as slant line to relief. 'Kitsch image' showed free and light imagery by creating unique hair style with various colors; expressing lips mostly with colors similar to skin tone or by restraining colors on lips. 'Decadence image' showed messy and foul sensation with unstandardized eye make-up and matt skin of shimmer, glossy and pale tone, also with black colored lips; 'Retro image' expressed reinterpretation of images from 1920${\sim}$1960 to contemporary styles.

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Hysteresis Characteristics of Buckling Restrained Brace with Precast RC Restraining Elements (조립형 프리캐스트 콘크리트 보강재를 가지는 비좌굴가새의 이력특성)

  • Shin, Seung-Hoon;Oh, Sang-Hoon
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.20 no.1
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    • pp.72-84
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    • 2016
  • The conventional brace system is generally accepted as the lateral load resisting system for steel structures due to efficient story drift control and economic feasibility. But lateral stiffness of the structure decreases when buckling happens to the brace in compression, so that it results in unstable structure with unstable hysteresis behavior through strength deterioration. Buckling restrained brace(BRB) system, in which steel core is confined by mortar/concrete-filled tube, represents stable behavior in the post-yield range because the core's buckling is restrained. So, seismic performance of BRB is much better than that of conventional brace system in point of energy absorption capacity, and it is applied the most in high seismicity regions as damper element. BRBs with various shaped-sections have been developed across the globe, but the shapes experimented in Korea are now quite limited. In this study, we considered built-up type of restraining member made up of precast reinforcement concrete and the steel core. we experimented the BRB according to AISC(2005) and evaluated seismic performances and hysteresis characteristics.