• Title/Summary/Keyword: External Wall

Search Result 558, Processing Time 0.028 seconds

Self Contained Wall--Climbing Robot with Closed Link Mechanism

  • Taehun Kang;Park, Jaejun;Kim, Hyungsuk;Park, Hyoukryeol
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2002.10a
    • /
    • pp.92.1-92
    • /
    • 2002
  • $\textbullet$ A compact and robust wall-climbing robot, called MRWALLSPECT-II, is developed. $\textbullet$ The robot is a self-contained system for scanning external surfaces of gas or oil tank. $\textbullet$ The robot has advantages of reduced actuators, parts and easy control. $\textbullet$ The mechanism of the robot employs a closed link mechanism. $\textbullet$ Self-Contained, Wall-Climbing, MRWALLSPECT

  • PDF

CFD Analysis of External Balance Strut Supporting Wind Tunnel Model (CFD를 이용한 풍동 시험 모델 지지대의 공력 특성 해석)

  • Kim C. W.;Park Y. M.;Lee J. Y.
    • 한국전산유체공학회:학술대회논문집
    • /
    • 2003.08a
    • /
    • pp.102-105
    • /
    • 2003
  • The effect of the external balance strut on the wind tunnel model is investigated with simplified geometries. For this study, flat plate and elliptic wing are simulated with and without a cylinder. Pressure and wall shear stress distribution are analyzed to understand the effect of the cylinder.

  • PDF

Reinforced Earth Retaining Wall of The Collapsed-A Case Study. (보강토옹벽의 사고사례에 관한 연구)

  • Yoo, Chung-Sik;Jung, Hyuk-Sang;Lee, Soung-Woo
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2004.03b
    • /
    • pp.958-967
    • /
    • 2004
  • This paper deal with cause and analysis about case of collapsed reinforced-soil retaining wall. The analysis of the cause was carried through experimentation, slop stability analysis and literature study. The experimentation treated the large direct shear test, the hydraulic conductivity test and the other basic test through backfill extracted from collapsed reinforced-soil retaining wall. The ultimate tensile strength was established by rib tensile strength test of geogrid. The analysis of internal and external stability of reinforced-soil retaining wall was performed on the basis of parameters. The result of analysis, reinforced-soil retaining wall and the slope at the dry season are stable. However, the factors that fine-grained soil at hydrometer test exceed the standard of the design, rainfall duration is too long at the time of collapse and monthly pricipitation is heavy are cause of the collapse.

  • PDF

A Study on the Role of Free-standing Wall in the Architectural Composition (건축구성에 있어서 가벽의 역할에 관한 연구)

  • 곽기표
    • Korean Institute of Interior Design Journal
    • /
    • no.41
    • /
    • pp.80-87
    • /
    • 2003
  • This paper attempts to examine the historical changes, the characteristics and the role of free-standing wall from the viewpoint of architectural composition. After modern times the wall gets free of structure and the view of formative art changes, which become a basis of the conscious use of free-standing wall. It plays a role of getting territoriality and placeness, by defining the space at the external territory and it is used as apparatus which controls circulation and orientation externally At the same time it is used as an instrument to blur the border to make mutual intersection and plays a role of introducing and controling the environment. The free-standing wall controls the architectural form to emphasize plasticity and is used to define a geometrical frame and maintain the urban context. In view of the results so far achieved, the free-standing wall is used as general vocabulary of modulating the border of space and the architectural form since modern architecture.

Investigation on Behavior of Two-Level Soil-Reinforced Segmental Retaining Walls Using Finite Element Analysis (유한요소해석을 통한 계단식 보강토 옹벽의 거동특성)

  • 유충식;전영우
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2002.10a
    • /
    • pp.689-696
    • /
    • 2002
  • The behavior of two-level soil-reinforced segmental retaining wall was examined using the finite element analysis. A number of different case was analyzed by varying the reinforcement length and the offset distance between the upper and lower wall. The results indicate that the interaction between the upper and lower walls can be neglected the upper wall is located beyond the distance of the lower wall height. A so found is that for moderate offset distances, the interaction between the two walls generally is limited to the external stability of the wall. Implication of the findings are discussed

  • PDF

Mechanical behavior test and analysis of HEH sandwich external wall panel

  • Wu, Xiangguo;Zhang, Xuesen;Tao, Xiaokun;Yang, Ming;Yu, Qun;Qiu, Faqiang
    • Advances in concrete construction
    • /
    • v.13 no.2
    • /
    • pp.153-162
    • /
    • 2022
  • Prefabricated exterior wall panel is the main non-load-bearing component of assembly building, which affects the comprehensive performance of thermal insulation and durability of the building. It is of great significance to develop new prefabricated exterior wall panel with durable and lightweight characteristics for the development of energy-saving and assembly building. In the prefabricated sandwich insulation hanging wall panel, the selection of material for the outer layer and the arrangement of the connector of the inner and outer wall layers affect the mechanical performance and durability of the wall panels. In this paper, high performance cement-based composites (HPFRC) are used in the outer layer of the new type wall panel. FRP bars are used as the interface connector. Through experiments and analysis, the influence of the arrangement of connectors on the mechanical behaviors of thin-walled composite wall panel and the panel with window openings under two working conditions are investigated. The failure modes and the role of connectors of thin-walled composite wallboard are analyzed. The influence of the thickness of the wall layer and their combination on the strain growth of the control section, the initial crack resistance, the ultimate bearing capacity and the deformation of the wall panels are analyzed. The research work provides a technical reference for the engineering design of the light-weight thin-walled and durable composite sandwich wall panel.

The Effects of Sitting in a Crossed Legs Posture on the Vertebral Angle, Chest Wall Mobility, Pulmonary Function, and Respiratory Muscle Activity: A Preliminary Study

  • Ahn, Hee-Eun;Yoon, Tae-Lim
    • Journal of the Korean Society of Physical Medicine
    • /
    • v.14 no.3
    • /
    • pp.13-20
    • /
    • 2019
  • PURPOSE: Sitting with crossed legs may have an effect on maintaining a healthy body posture and proper functioning of the respiratory system. Thus, this study's objective was to identify whether or not sitting with crossed legs affects the vertebral angle, chest wall mobility, the pulmonary function, and the activity of the respiratory muscles. METHODS: Thirty healthy subjects were recruited for this study (16 males and 14 females). The vertebral angle, chest wall mobility, pulmonary function, and the activity of the respiratory muscle were measured while the subjects sat in the correct posture and these factors were again measured with the subjects seated with their legs crossed. Three-dimensional motion analysis was used to determine the trunk and lumbar vertebral angles. Surface electromyography was employed to measure the sternocleidomastoid, the rectus abdominis, and the external and internal oblique abdominis muscles. A tapeline was utilized to evaluate the subjects' chest wall mobility. Spirometry was assessed to determine the forced vital capacity and forced expiratory volume in one second. Paired t-tests were then performed (p<.05). RESULTS: There were significant differences in the trunk and lumbar flexion angles, the chest wall mobility, the activity of the right external oblique muscle, and the left internal oblique abdominis muscle. However, the difference in pulmonary function did not reach statistical significance. CONCLUSION: A crossed leg posture caused slight thoracic extension and lumbar flexion, which may lead to a decrease of the chest wall mobility and also to an imbalance of the abdominal muscles. Therefore, sitting with a crossed leg posture should be avoided. Yet a crossed leg posture did not have any clinical effect on the pulmonary function of healthy people. It may be necessary to study the effects of sitting with crossed legs over an extended period of time for patients suffering with impaired respiratory function.

A Study on Simulation for Decreasing Energy Demand According to Window-to-Wall Ratio and Installation Blind System in Building (블라인드 도입과 창면적비에 따른 표준건축물의 에너지 수요 저감에 대한 시뮬레이션 연구)

  • Kang, Suk-Min;Lee, Tae-Kyu;Kim, Jeong-Uk
    • Journal of Korean Institute of Architectural Sustainable Environment and Building Systems
    • /
    • v.12 no.6
    • /
    • pp.531-542
    • /
    • 2018
  • Building energy demands have highly risen in modern society; thus, It is necessary to reduce building energy demands especially commercial buildings adopting a curtain wall architecture. Curtain wall architectures have a high ratio of windows which is a vulnerable in heat insulations as cladding. In order to complement insulation performance of windows in these buildings, there are various methods adopted often such as installing blinds, wing wall and films. There are two suggestions of this paper. 1) WWR (Window-to-Wall Ratio) makes a impaction of energy demands in buildings. 2) Another one is an efficiency of blind systems which are installed in buildings in order to reduce cooling demands. It is also critical to make fundamental model for low-energy building construction by processing a lot of simulation As a result by this study, 1) an external blind system is more useful for reducing cooling energy demands rather than an internal blind system. 2) Buildings which have a large window require more amount of cooling demands. In case of WWR 45%, it needs more cooling energy rather than WWR 15% model's 3) Adopting blind system would reduce energy demands. WWR 45% model with external blind systems reduces about 4% of cooling energy demands compared to same model without any blind systems.4) it is necessary to study an efficiency of blind systems combined with renewable energy and it will be possible to reduce more energy demand in building significantly.

Recent Progress of Spray-Wall Interaction Research

  • Lee Sang-Yong;Ryu Sung-Uk
    • Journal of Mechanical Science and Technology
    • /
    • v.20 no.8
    • /
    • pp.1101-1117
    • /
    • 2006
  • In the present article, recent progress of spray-wall interaction research has been reviewed. Studies on the spray-wall interaction phenomena can be categorized mainly into three groups: experiments on single drop impact and spray (multiple-drop) impingement, and development of comprehensive models. The criteria of wall-impingement regimes (i.e., stick, rebound, spread, splash, boiling induced breakup, breakup, and rebound with breakup) and the post-impingement characteristics (mostly for splash and rebound) are the main subjects of the single-drop impingement studies. Experimental studies on spray-wall impingement phenomena cover examination of the outline shape and internal structure of a spray after the wall impact. Various prediction models for the spray-wall impingement phenomena have been developed based on the experiments on the single drop impact and the spray impingement. In the present article, details on the wall-impingement criteria and post-impingement characteristics of single drops, external and internal structures of the spray after the wall impact, and their prediction models are reviewed.