• Title/Summary/Keyword: Light fixture

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Analysis of Urban Park Nightscape based on the Design-Construction Process and Current Status - Focused on Yeouido Park - (도시공원 야간경관의 조성 과정과 실태 분석 - 여의도공원을 중심으로 -)

  • Kim, Hyun-Geun;Kim, Ah-Yeon
    • Journal of the Korean Institute of Landscape Architecture
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    • v.46 no.2
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    • pp.14-26
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    • 2018
  • Light has been an essential part of human life. The advancement of technology has changed cities' nightscape and night activities in a drastic way. Lighting has influenced the identity of a city while promoting a variety of civic nighttime cultural pursuits, yet lighting design has not been considered adequately in the field of landscape architecture. This study aims to analyze the current status of lighting in urban parks through interviews with professionals, literature and regulation reviews, analysis of design documents and a field survey focused on Yeouido Park in Seoul. The findings and improvement directions are as follows. First, it is necessary to develop a specific lighting design method in order to avoid a marginalized, passive approach such as light fixture installation. Second, the existing standards of illuminance by KS A 3011 regulating only horizontal illuminance has turned out not to evaluate the current nightscape of urban parks properly. Therefore the criteria and guideline for analysis and design for nightscape should be articulated. Third, there are no design or management strategies to consider the changing landscape of urban parks, which is necessary due to the changing characteristics of park ecosystems. Lastly, detailed guidelines for distinguished spaces in urban parks should be studied and suggested.

AN EXPERIMENTAL STUDY OF NEWLY DESIGNED IMPLANT WITH RBM SURFACE IN THE RABBIT TIBIA : RESONANCE FREQUENCY ANALYSIS AND REMOVAL TORQUE STUDY

  • Won Mi-Kyoung;Park Chan-Jin;Chang Kyoung-Soo;Kim Chang-Whe;Kim Yung-Soo;Isa Zakiahbt Mohd;Ariffin Yusnidar Tajul
    • The Journal of Korean Academy of Prosthodontics
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    • v.41 no.6
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    • pp.720-731
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    • 2003
  • Statement of problem. The importance of fixture design and surface treatment. Purpose. The clinical success of dental in plants is affected by many factors such like as degree of osseointegration, the effective load dispersion for the prostheses, and a lot of attempts have been made to overcome the difficulties. In this study, efforts were made to find the possibility of clinical acceptance of the dental implants of newly designed surface and resorbable blast media surcace. Materials and methods. In this study, two groups of custom-made, screw-shaped implants were prepared. The first with the consisting of Branemark clone design and the other with the new design. These implants were divided into four groups according to the kinds of surface treatment. Four implants($AVANA^{(R)}$, Osstem, Busan, Korea)of each group were installed in twenty rabbits. Group A was consisted of Branemark done implant left as machined, Group B with Branemark clone implants with RBM(Resorbable blast media) surface, Group C with newly designed implants left as machined and Group D with newly designed implants with RBM surface. One of the twenty rabbits died from inflammation and the observation was made for six weeks. Specimens from four groups were observed using scanning electron microscopy with 40, 100, 1000 magnification power and microsurface structures were measured by white-light scanning interferometry for three dimensional surface roughness measurements(Accura $2000^{(R)}$, Intek-Plus, Korea.). Removal torque was measured in 17 rabbits using digital torque gauge(MGT 12R, Mark-10 corp., NY, U.S.A.) immediately after the sacrifice and two rabbits were used for the histologic preparation(EXAKT $310^{(R)}$, Heraeus Kulzer, wehrheim, Germany) of specimens and observed under light microscope. Resonance frequency measurement($Osstell^{(R)}$) was taken with the 19 rabbits at the beginning of the implant fixation and immediately after the sacrifice. Results. Following results were taken from the experiment. 1. The surface of the RBM implants as seen with SEM had rough and irregular pattern with reticular formation compared to that of fumed specimens showing different surface topographies. 2. The newly designed implant with RBM surface had high removal torque value among four groups with no statistical significance. The average removal torque was $49.95{\pm}6.70Ncm$ in Group A, $51.15{\pm}4.40Ncm$ in Group B, $50.78{\pm}9.37Ncm$ in Group C, $51.09{\pm}4.69Ncm$ in Group D. 3. The RFA values were $70.8{\pm}4.3Hz$ in Group A, $71.8{\pm}3.1Hz$ in Group B, $70.9{\pm}2.5Hz$, $72.7{\pm}2.5Hz$ in Group D. Higher values were noted in the groups which had surface treatment compared to the untreated groups with no statistical significance. 4. The results from the histomorphometric evaluation showed a mean percentage of bone-to-implant contact of $45{\pm}0.5%$ in Group A, $55{\pm}3%$ in Group B, $49.5{\pm}0.5%$ in Group C, and $55{\pm}3%$ in Group D. Quite amount of newly formed bone were observed at the surface RBM-treated implants in bone marrow space.