• Title/Summary/Keyword: Movable

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A Study on the Blanking Characteristic of Anti- Vibration Sheet Metal (제진 강판의 블랭킹 가공 특성에 관한 연구)

  • 이광복;이용길;김종호
    • Transactions of Materials Processing
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    • v.12 no.8
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    • pp.724-729
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    • 2003
  • In order to study the shearing characteristic of anti-vibration sheet metal which is used to reduce vibration noise, a blanking die was manufactured to blank a workpiece. The variables employed in this study were clearance, type of stripper plate, position of the rubber layer and type of the die design. These variables were used to study the effects on burr height, blank diameter and camber height. In the case of burr height from experimental investigation, the push-back die, combined with a movable stripper plate, showed greater burr height. The rubber-top position of a workpiece resulted in better qualities regardless of working variables. In the comparison of diameter measurement, the use of the push-back die with a fixed stripper plate, with a 4.5% clearance, showed better accuracy. For comparing camber height, the push-back die resulted in less cambering than the drop-through die. Also, the larger the clearance, the greater was the camber height. Considering experimental results, the shearing of anti-vibrational sheet metal is best achieved when the rubber layer is laying on the top, blanked with a fixed stripper plate in a push-back die, with a 4.5% clearance.

Evaluation of the effect of smart façade systems in reducing dynamic response of structures subjected to seismic loads

  • Samali, Bijan;Abtahi, Pouya
    • Earthquakes and Structures
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    • v.11 no.6
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    • pp.983-1000
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    • 2016
  • To date the engineering community has seen facade systems as non-structural elements with high aesthetic value and a barrier between the outdoor and indoor environments. The role of facades in energy use in a building has also been recognized and the industry is also witnessing the emergence of many energy efficient facade systems. This paper will focus on using exterior skin of the double skin facade system as a dissipative movable element during earthquake excitation. The main aim of this study is to investigate the potential of the facade system to act as a damper system to reduce earthquake-induced vibration of the primary structure. Unlike traditional mass dampers, which are usually placed at the top level of structures, the movable/smart double skin facade systems are distributed throughout the entire height of building structures. The outer skin is moveable and can act as a multi tuned mass dampers (MTMDs) that move and dissipate energy during strong earthquake motions. In this paper, using a three dimensional 10-storey building structure as the example, it is shown that with optimal choice of materials for stiffness and damping of brackets connecting the two skins, a substantial portion of earthquake induced vibration energy can be dissipated which leads to avoiding expensive ductile seismic designs. It is shown that the engineering demand parameters (EDPs) for a low-rise building structures subjected to moderate to severe earthquakes can be substantially reduced by introduction of a smart designed double skin system.

The Deformation Measurement of Simulated Ground using Movable Orientation Board for Photogrammetry (사진측량용 이동식 표정판을 이용한 모형지반 변형량 측정)

  • Lee, Hyo-Seong
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.26 no.4
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    • pp.323-331
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    • 2008
  • Digital close-range photogrammetric technique can measure and describe 3D geometric form from 2D image. This technique is a growing applicability in the field of sciences. Nevertheless, civil and mechanical field, which need measurements as precise as possible, use expensive measuring instruments in general. In addition there are occasions for analysis by means of visual method, since appropriate measuring instruments have been not yet available. This study therefore developed digital close-range photogrammetric technique with a movable orientation board to quickly measure deformation before and after destruction from simulated ground model of reinforced-soil wall. Then the results are compared with the measurements obtained using digital theodolite.

A Study on the Background and Characteristics of Textile Wallcovering in Flemish Painting (플랑드르 회화에 표현된 벽걸이 직물의 발달 배경과 특징에 관한 연구)

  • Lee, Joonhan;Kim, Sun Mee
    • Journal of Fashion Business
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    • v.24 no.4
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    • pp.19-29
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    • 2020
  • The purpose of this study was to investigate Renaissance wall-covering fabrics through Flemish paintings, that provides the details of the origin and development of background of modern wallcovering. The methods of the study are as follows. First, the background of textile development of Flanders in the 14th to 16th centuries were examined through a prior study. Second, the shape and use of wallcoverings in paintings painted during that time were analyzed and the process of changing to modern forms was studied. The residential environment with many stone buildings in relatively humid and cold weather created a need for decorative fabrics. Back then, the wool and flax fabric were not allowed to be worn on the body, so the materials were used for the development of interior fabrics. The characteristics of wall covering in Flemish paint can be summarized with movable, allegory, and decoration. Movable stems from the arrival of the emerging aristocrats of Flanders, who had enormous commercial trade and carried decorative fabrics; the mobility has become an allegory in reality as the royal and aristocratic use of wall-decorated fabrics is the symbol of authority. In addition, unlike Italy, where silk was procured from the East, fabrics manufactured using flax and wool were not suitable for clothing in terms of religion and practicality and were used to decorate walls.

A Study on Development of Movable u-POS System based on RFID (RFID 기반의 이동형 u-POS 시스템 개발에 관한 연구)

  • Jho, Yong-Chul;Li, Zhong-Shi;Lee, Chang-Ho
    • Journal of the Korea Safety Management & Science
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    • v.9 no.6
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    • pp.155-162
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    • 2007
  • Recently, retail store automation appliance market is changed with traditional POS systems techniques and RFID, radio POS system, and self checkout system, etc. in the foreign advanced distribution industry. Retailers and consumers require convenient POS system which can provide more functions and fast service. These requests bring to rapid evolution of various H/W and S/W corresponding with POS system. In this study with the POS systems and the RFID technology we develop core technology of movable u-POS system based on RFID that can use in large store. So we propose u-Cart system that can alternate the current shopping cart and POS terminal and that provide value added services to customer. As the result we present the configuration of u-Cart terminal device(WMDT : Wireless Mobile Data Terminal) including RFID reader module that can provide various information to consumer and some convenient client applications that are running in WMDT and u-POS administration service module.

Authoring Personal Virtual Studio Using Tangible Augmented Reality (탠저블 증강현실을 활용한 개인용 가상스튜디오 저작)

  • Rhee, Gue-Won;Lee, Jae-Yeol;Nam, Ji-Seung;Hong, Sung-Hoon
    • Korean Journal of Computational Design and Engineering
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    • v.13 no.2
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    • pp.77-88
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    • 2008
  • Nowadays personal users create a variety of multi-media contents and share them with others through various devices over the Internet since the concept of user created content (UCC) has been widely accepted as a new paradigm in today's multi-media market, which has broken the boundary of contents providers and consumers. This paradigm shift has also introduced a new business model that makes it possible for them to create their own multi-media contents for commercial purpose. This paper proposes a tangible virtual studio using augmented reality to author multi-media contents easily and intuitively for personal broadcasting and personal content generation. It provides a set of tangible interfaces and devices such as visual markers, cameras, movable and rotatable arms carrying cameras, and miniaturized set. They can offer an easy-to-use interface in an immersive environment and an easy switching mechanism between tangible environment and virtual environment. This paper also discusses how to remove inconsistency between real objects and virtual objects during the AR-enabled visualization with a context-adaptable tracking method. The context-adaptable tracking method not only adjusts the locations of invisible markers by interpolating the locations of existing reference markers, but also removes a jumping effect of movable virtual objects when their references are changed from one marker to another.

A Numerical study for the efficacy of flow injection on the diminution of rudder cavitation

  • Seo, Dae-Won;Lee, Seung-Hee;Kim, Hyo-Chul;Oh, Jung-Keun
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.2 no.2
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    • pp.104-111
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    • 2010
  • The complete avoidance of cavitation, as a result of gap flow between the fixed and movable portion of a horn type rudder system, is difficult. To reduce gap flow, it is a common practice to attach a half round prismatic bar that protrudes beyond the concave surface of the horn facing the gap and laid along the centerplane of the rudder. However the employment of such a device does not always yield satisfactory results. Previously, the authors have shown that a pair of blocking bars, attached on the convex surface of the movable portion, better enhance the blocking ability of gap flow to that of a single centre bar installed on the concave surface. This also circumvents difficulties that might occur in practical applications. In the present study, a series of numerical computations show that flow injected into the gap of a rudder may also block the flow within, without employment of any physical devices, such as a half circular bar. This study also shows that the combination of flow injection and blocking bars may result in the synergic augmentation of blocking efficiency of gap flow, as demonstrated in computations for a three dimensional rudder system.

Optimal Posture Control for Unmanned Bicycle (무인자전거 최적자세제어)

  • Yang, Ji-Hyuk;Lee, Sang-Yong;Kim, Seuk-Yun;Lee, Young-Sam;Kwon, Oh-Kyu
    • Journal of Institute of Control, Robotics and Systems
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    • v.17 no.10
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    • pp.1006-1013
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    • 2011
  • In this paper, we propose an optimal posture control law for an unmanned bicycle by deriving linear bicycle model from fully nonlinear differential equations. We calculate each equilibrium point of a bicycle under any given turning radius and angular speed of rear wheel. There is only one equilibrium point when a bicycle goes straight, while there are a lot of equilibrium points in case of turning. We present an optimal equilibrium point which makes the leaning input minimum when a bicycle is turning. As human riders give rolling torque by moving center of gravity of a body, many previous studies use a movable mass to move center of gravity like humans do. Instead we propose a propeller as a new leaning input which generates rolling torque. The propeller thrust input makes bicycle model simpler and removes input magnitude constraint unlike a movable mass. The proposed controller can hold optimal equilibrium points using both steering input and leaning input. The simulation results on linear control for circular motion are demonstrated to show the validity of the proposed approach.

Shoreline Changes due to the Construction of Offshore Structure and its Numerical Calculation (이안 구조물 건설에 따른 해안선의 변화와 수치계산)

  • 신승호
    • Journal of Korean Port Research
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    • v.15 no.1
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    • pp.47-56
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    • 2001
  • A numerical model for practical use based on the 1-line theory is presented to simulate shoreline changes due to construction of offshore structures. The shoreline change model calculates the longshore sediment transport rate using breaking waves. Before the shoreline change model execution, a wave model, adopting the modified Boussinesq equation including the breaking parameters and bottom friction term, was used to provide the longshore distribution of the breaking waves. The contents of present model are outlined first. Then to examine the characteristics of this model, the effects of the parameters contained in this model are clarified through the calculations of shoreline changes for simple cases. Finally, as the guides for practical application of this model, several comments are made on the parameters used in the model, such as transport parameter, average beach slope, breaking height variation alongshore, depth of closure, etc. with the presentation of typical examples of 3-dimensional movable bed experimental results for application of this model. Here, beach change behind the offshore structures is represented by the movement of the shoreline position. Analysis gives that the transport parameters should be taken as site specific parameters in terms of time scale for the shoreline change and adjusted to achieve the best agreement between the calculated and the observed near the structures.

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Multi-directionally Movable Lambda Shape Transducer for Ultrasonic Motor (초음파 모터용 람다형 다방향 변환자)

  • Do, Young-Soo;Nam, Hyo-Duk;Kim, Young-Duk
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.21 no.2
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    • pp.131-136
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    • 2008
  • The transducer for multi-directionally movable ultrasonic motor having lambda shaped vibrators has been proposed and designed. The two branches cross at a right angle with each other at the tip. FEM analyses of lambda shaped transducer were carried out to find vibration modes for ultrasonic motor. The lambda shaped transducer has one symmetric mode and two anti-symmetric modes. The symmetric mode generates the normal direction motion of the tip. The lateral and vertical direction motion of the tip are excited by two anti-symmetric modes. The normal and lateral direction motions made an lateral elliptic trajectory. And the normal and vertical direction motions made an vertical elliptic trajectory normal to previous one. The transducer with 1 mm in thickness and 25 mm in length has been fabricated and evaluated. The resonance frequencies of the transducer was 32 kHz and 103 kHz. The tangential and vertical vibration displacement of the transducer having the lateral elliptic trajectory were $1.5{\mu}m\;and\;1.1{\mu}m$, respectively at the driving voltage of 100 Vpp and frequency of 32 kHz and 103 kHz. And the tangential and vertical vibration displacement of the transducer having the vertical elliptic trajectory were $0.4{\mu}m\;and\;0.2{\mu}m$, respectively at the same driving condition.