• Title/Summary/Keyword: Super Work

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A Study on the Productivity Analysis of Finishing Works on Super High-rise Mixed_use Building (초고층 주상복합 건축물 마감공사의 공종별 생산성 비교에 관한 연구)

  • Hong, Bo-Bae;Kim, Yong-Man;Kim, Ju-Hyung;Kim, Jae-Jun
    • KIEAE Journal
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    • v.10 no.5
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    • pp.165-170
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    • 2010
  • Super high-rise mixed use buildings require a longer period for construction. Especially finishing work takes up about 40% of the whole construction period. Thus, finishing work is becoming an important factor in determining the construction period along with earth work and frame work. As the expected returns added by the reduction of the period and cost in constructing super high-rise mixed use buildings are huge, the expectations are now increasing for the possible gains. In this respect, as the period of finishing work is easier to be shortened than that of frame work, the efforts to acquire the technical knowledge to reduce the finishing work period are now being required. Accordingly, in this study, we aimed at suggesting the basic data for designing an economic plan for finishing-work procedure by analyzing the productivity of each work type of finishing work procedure on the basis of the execution and results of a construction method as a time-flexible finishing work plan. For this, we categorized the work types of finishing work procedure into each work unit and provided a work-system for each of them. Also, with case studies, we calculated the detailed amounts of the work-loads, required materials, productivity, and productivity index of the main work types of finishing work procedure and each of their separate work units as well as analyzed the relationship between the value results to suggest a better way to improve its productivity.

An Experimental Study on the Characteristics and Lateral Pressure of Super-Workable Concrete (초유동 콘트리트의 재료적 특성과 거푸집 측압에 관한 실험적 연구)

  • 이준구
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.42 no.1
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    • pp.83-91
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    • 2000
  • The purpose of this study is to estimate quantitatively lateral pressure of super-workable fresh concrete applied to form-work of prototype structures, such as tall wall, retaining wall and beam. As a result of this experiment, a function applicable to design a form work system and to predict lateral pressure curve is formulated . Super-workable concrete may be used for the structures reinforced with dense re-bar like box culvert to place concrete at a time, and this study for lateral pressure of super-workable concrete may be useful for form design.

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Non-stationary vibration and super-harmonic resonances of nonlinear viscoelastic nano-resonators

  • Ajri, Masoud;Rastgoo, Abbas;Fakhrabadi, Mir Masoud Seyyed
    • Structural Engineering and Mechanics
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    • v.70 no.5
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    • pp.623-637
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    • 2019
  • This paper analyzes the non-stationary vibration and super-harmonic resonances in nonlinear dynamic motion of viscoelastic nano-resonators. For this purpose, a new coupled size-dependent model is developed for a plate-shape nano-resonator made of nonlinear viscoelastic material based on modified coupled stress theory. The virtual work induced by viscous forces obtained in the framework of the Leaderman integral for the size-independent and size-dependent stress tensors. With incorporating the size-dependent potential energy, kinetic energy, and an external excitation force work based on Hamilton's principle, the viscous work equation is balanced. The resulting size-dependent viscoelastically coupled equations are solved using the expansion theory, Galerkin method and the fourth-order Runge-Kutta technique. The Hilbert-Huang transform is performed to examine the effects of the viscoelastic parameter and initial excitation values on the nanosystem free vibration. Furthermore, the secondary resonance due to the super-harmonic motions are examined in the form of frequency response, force response, Poincare map, phase portrait and fast Fourier transforms. The results show that the vibration of viscoelastic nanosystem is non-stationary at higher excitation values unlike the elastic ones. In addition, ignoring the small-size effects shifts the secondary resonance, significantly.

A Study on a Concept of 'Prototype' for Enhancing the Collocation Function of Catalog (목록의 집중기능을 향상시키는 '원형' 개념에 관한 연구)

  • Lee, Hye-Won
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.22 no.3
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    • pp.91-107
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    • 2011
  • Work is a bibliographic entity serving a key role for the collocation function of catalog. This study analyzed the concept of work, provided a new device to complement conventional FRBR work. The 'prototype' was suggested to enhance the collocation function of catalog, the highest level in FRBR. This study explained the definition, attributes of prototype, and relationships between prototype and work within FRBR model.

Residential Satisfaction of Households living in Super-High Rise Apartment in Ulsan (울산시 초고층 아파트 거주자의 주거만족도)

  • 김선중;김수정
    • Journal of the Korean Home Economics Association
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    • v.37 no.3
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    • pp.101-110
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    • 1999
  • The purpose of this study was to invesitigate the residential satisfaction of households living in super-high rise apartment. The questionnarles were collected from 244 residents living in super-high rise apartment above 20 stories located in Ulsan. Used statistical techniques were frequency, one-way ANOVA. The major findings were as follows: 1) Although the respondents were dissatisfied with super-high rise apartments, they chose present dwelling due to public transportation, easy access to work, and other community facilities. 2) Households who have more educated husband and wife and younger child were less satisfied with current dwelling. 3) The attrative features of super-high rise apartment were interior facilities, exterior environment, and social relations, While the negative features were interior environment, safety, and psychological stability.

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The Nonlinear Equalizer for Super-RENS Read-out Signals using an Asymmetric Waveform Model (비대칭 신호 모델을 이용한 super-RENS 신호에서의 비선형 등화기)

  • Moon, Woosik;Park, Sehwang;Lee, Jieun;Im, Sungbin
    • Journal of the Institute of Electronics and Information Engineers
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    • v.51 no.5
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    • pp.70-75
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    • 2014
  • Super-resolution near-field structure (super-RENS) read-out samples are affected by a nonlinear and noncausal channel, which results in inter-symbol interference (ISI). In this study, we investigate asymmetry or domain bloom in super-RENS in terms of equalization. Domain bloom is caused by writing process in optical recording. We assume in this work that the asymmetry symbol conversion scheme is to generate asymmetric symbols, and then a linear finite impulse response filter can model the read-out channel. For equalizing this overall nonlinear channel, the read-out signals are deconvolved with the finite impulse response filter and its output is decided based on the decision rule table that is developed from the asymmetry symbol conversion scheme. The proposed equalizer is investigated with the simulations and the real super-RENS samples in terms of raw bit error rate.

Application of Ultrasonic Vibration Energy on Eco-superfinishing and Surface Hardening Treatment of Cold Work Roller (초음파 진동에너지를 이용한 냉간 압연롤러 표면의 환경 친화적 초정밀 사상 및 표면 경화 처리 및 시험)

  • Y.S. Pyoun;Park, J.H.;C.H. Han;Park, Y.;I.S. Cho;N. Azuma;Lee, J.H.;Kim, C.S.;Park, C.H.
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2002.05a
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    • pp.39-39
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    • 2002
  • In order to improve wear and fatigue resistance of the structural materials, especially cold work roller for 304 stainless steel, an eco-super-finishing and surface hardening treatment using ultrasonic vibration energy was developed and applied to the SKD-ll roller. The eco-super-finishing machine was designed and fabricated by DesignMecha Co, by its own technology. It was observed that the surface roughness, hardness and residual stress were changed from $Ra{\;}={\;}O.25\mu\textrm{m}$, Hv=710 and ${\sigma}$={\;}+400{\;}MPa{\;}to{\;}Ra{\;}={\;}0.165\mu\textrm{m}$, Hv = 1200 and ${\sigma}=-610$ MPa after 20 KHz micro-cold forging, which means almost equal to the 300 % improvement of life-time.

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New Field in Photoelectrochemistry: Photocatalytic, Super-hydrophilic and Super-hydrophobic Functions of $TiO_2$ Coatings

  • Fujishima Akira;Hashimoto Kazuhito
    • Journal of the Korean Electrochemical Society
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    • v.3 no.2
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    • pp.81-84
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    • 2000
  • This article deals with various photochemical processes occurring at $TiO_2$ surface and its applications in practical living conditions. In the first part, we present an overview of $TiO_2$ photocatalysis under weak W illumination with a special emphasis on bactericidal and detoxification properties of $TiO_2$ films. The second part deals with the photoinduced super hydrophilic TiCt surftce which has a wide commercial applications. In the last part, we present our recent work on boehmite-based super hydrophobic surfaces containing small amount of $TiO_2$ to obtain self-cleaning effect.

A Fundamental Study on the Workability and Engineering Properties of Super High Strength Concrete Replaced Cement As Fly ash (플라이애쉬를 대체한 초고강도 콘크리트의 시공성 및 공학적 특성에 관한 기초적 연구)

  • 류광일;윤병수;김진만;남상일;김무한
    • Proceedings of the Korea Concrete Institute Conference
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    • 1993.10a
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    • pp.5-10
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    • 1993
  • Recently, owing to efficiency of the concrete work and the rationalization of construction structures, concrete is required to be super high strength. Furthermore, it is take a growing interest in execution and manufacture for super high strength concrete. This study is to investigate and analyze the influenced of flyash affecting on workability and engineering properties of super high strength concrete. In this experiment, the 28day's compressive strength of concrete using 15mm size of aggregate and flyash is over 800㎏/㎠ in the 20°/wt of water∼cement ratio. And the concrete using flyash have higher tensile strength than plain concrete.

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The Study of noise and vibration on application of the method breaking & excavating rock(Super wedge) (암파쇄굴착공법(Super wedge) 적용에 따른 소음.진동에 대한 고찰)

  • Won, Yeon-Ho;Kang, Choo-Won;Ryu, Chang-Ha
    • Proceedings of the KSEE Conference
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    • 2006.10a
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    • pp.167-184
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    • 2006
  • There is cattle shed and house structure of a country village in the vicinity of the construction site. that is why the environmental effect evaluation on blasting had been done in advance to prevent any harm to those from the work. As the result, it is impossible to apply to the blasting method, and the Super wedge method, a kind of a rock-splitting method which there is no secondary breaking by a breaker of the methods breaking &excavating rock according to the classification of the blasting method by the ministry of construction & transpotation, applied to decrease noise and vibration, and to the work classification, the extent of noise and vibration measured with the instrument only for noise(SC-310c) and with the instrument only for vibration(BLASTMATE) respectively. A drilling, splitting, collecting, loading works at the closest point(about 10m) is barely possible on the consideration of vibration to the result of measurement, but carefulness needs on moving of equipment. On the case of noise, even drilling, collecting, loading work except splitting at the comparatively close point(about 20m) is difficult. So, the method breaking &excavating rock according to the classification of the blasting method by the ministry of construction & transpotation has to apply in consideration of noise level in accordance with the work processing.

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