• 제목/요약/키워드: loss of attachment

검색결과 211건 처리시간 0.026초

플로워 진동 저감을 위한 제진재 해석 프로세스 연구 (Study on the Analysis Process of the Damping Material for Reduced Floor Vibration)

  • 김기창;황미경;서성훈;최재민;김찬묵;김진택
    • 한국소음진동공학회논문집
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    • 제21권4호
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    • pp.333-338
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    • 2011
  • This paper describes the design process of floor damping material optimization to reduce structure borne noise. This process uses finite element analysis(FEA) along with experimental techniques to complement each other. The objective of this approach was to develop an optimized damping material application layout and thickness at the initial design stage. The first step is to find the sensitivity areas of vehicle body without damping material applied using FEA. In order to determine the high vibration areas of the floor panel, the velocity was measured using a scanning laser vibrometer from 20 Hz to 300 Hz. To excite the floor panel vibration, shaker was placed at the front suspension attachment point. The second step is the optimization process to determine the light weight solution of damping material. The design guideline of damping material was suggested that the lightweight solution was verified using test result of road noise. Design engineer could efficiently decide the design variable of damping material using parameter analysis results in early design stage.

Fouling control in a woven fibre microfiltration membrane for water treatment

  • Chollom, Martha Noro;Rathilal, Sudesh;Pikwa, Kumnandi;Pillay, Lingham
    • Environmental Engineering Research
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    • 제24권3호
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    • pp.418-426
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    • 2019
  • Current available commercial membranes are not robust and are therefore destroyed if left to dry out or handled roughly. Woven fibre microfiltration (WFMF) membranes have advantages over its competitors with respect to durability, thus, favourable for the developing economies and operation during rough conditions. Evaluation of the effects of aeration and brushing as a flux enhancement strategies for WFMF membrane was the purpose of this study. The WFMF membrane was found to be susceptible to pore plugging by colloidal material and adsorption/attachment by microbiological contaminants. This led to a 50% loss in flux. Aeration as a single flux enhancement strategy proved insufficient to maintain high flux successfully. Therefore combined flux enhancement strategies yielded the best results.

An innovative prostheses design for rehabilitation of severely mutilated dentition: a case report

  • Abduo, Jaafar
    • The Journal of Advanced Prosthodontics
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    • 제3권1호
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    • pp.37-42
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    • 2011
  • Partial edentulism has multiple implications in relation to function, esthetics and future rehabilitative treatment. This case report illustrates the management of a patient with extreme consequences of partial edentulism. The main clinical findings were unopposed remaining teeth, overeruption of the remaining teeth, loss of vertical dimension of occlusion, and significant disfigurement of the occlusal plane. Following the diagnostic procedure, a well-coordinated prosthodontic treatment involving liaison with other dental disciplines was indicated. The management involved an innovative combination of fixed and removable prostheses in conjunction with crown lengthening surgery and strategic implant placement. Series of provisional prostheses were applied to facilitate the transition to the final treatment.

건식 열교환기를 이용한 백연방지 냉각탑 성능의 수치해석적 연구 (A Numerical Study on the Performance Analysis of Plume Abatement Cooling Tower with Dry Type Heat Exchanger)

  • 김병조;최영기
    • 설비공학논문집
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    • 제15권12호
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    • pp.1018-1027
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    • 2003
  • This study treats the analysis of the performance and the design of plume abatement wet/dry cooling tower with dry type heat exchanger using a numerical method. A two-dimensional analysis is performed using the finite volume method for mechanical draft counterflow and crossflow tower. For a coupling problem between water and air system, a turbulent two phase flow is considered. Effectiveness-NTU method is used for modeling of the dry type heat exchanger. The parameter change simulations of the outer wall shape, the relative flowrate of air, and attachment of an air mixer are performed to examine the effect on plume abatement. It is found that if the relative air flowrate ratio and the adequate air mixer type are chosen well in addition to the ratio of water to air flowrate, the loss of the cooling capacity and the additional cost are reduced and the plume is abated.

치주질환 및 임플란트 주위 질환의 새 분류 (A new classification of periodontal and peri-implant disease)

  • 신현승
    • 대한치과의사협회지
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    • 제57권12호
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    • pp.758-767
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    • 2019
  • The classification of periodontal disease in 1999 has been widely used for determining a diagnosis, establishing a treatment plan, and evaluating the prognosis of the patient with periodontal disease. However, scientific evidence from many studies indicates the need for a new classification system for periodontal and peri-implant disease. Summary at 2017 world workshop as follows: 1) Periodontal health and peri-implant health was defined; 2) Chronic periodontitis and aggressive periodontitis were unified as periodontitis; 3) Periodontitis was further classified by staging and grading to reflect disease severity and management complexity, rate of disease progression, respectively; 4) Periodontal disease as manifestation of systemic disease is based on the International Statistical Classification of Diseases and Related Health Problems-10 (ICD-10) code; 5) Periodontal biotype and biologic width was replaced to periodontal phenotype and supracrestal tissue attachment, respectively; 6) The excessive occlusal force was replaced by a traumatic occlusal force; 7) ≥3 mm of radiographic bone loss, ≥6 mm of pocket probing depth and bleeding on probing indicates peri-implantitis in the absence of radiograph at final prosthesis delivery.

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Numerical Study on the Performance Analysis of Plume Abatement Cooling Tower with Dry Type Heat Exchanger

  • Kim, Byung-Jo;Choi, Young-Ki
    • International Journal of Air-Conditioning and Refrigeration
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    • 제13권2호
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    • pp.61-70
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    • 2005
  • This study treats the numerical analysis of performance and design for plume abatement wet/dry cooling tower with a dry type heat exchanger. A two-dimensional analysis is performed using the finite volume method for mechanical draft counterflow and crossflow tower. For a coupling problem between water and air system, a turbulent two phase flow is considered. The Effectiveness-NTU method is used for modeling of the dry type heat exchanger. The parametric simulations such as the relative flowrate of air and attachment length of an air mixer are performed to examine the effect on plume abatement. It is found that if the relative air flowrate ratio and the adequate air mixer type are chosen well in addition to the ratio of water to air flowrate, the loss of cooling capacity and the additional cost are reduced and the plume is abated.

ELECTROSTATIC SPRAYER OF AGRICULTURAL CHEMICALS

  • Kang, T.G.;Lee, D.H.;Lee, C.S.;Kim, H.j.;Chung, S.J.
    • 한국농업기계학회:학술대회논문집
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    • 한국농업기계학회 2000년도 THE THIRD INTERNATIONAL CONFERENCE ON AGRICULTURAL MACHINERY ENGINEERING. V.III
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    • pp.811-818
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    • 2000
  • Agricultural chemicals spraying is one of the most efficient methods for pesticides control. General farming groups use Speed Sprayer but its deposition amount on practical crops is only 20% of total amount in SS case. Agricultural chemicals which fail to arrive the crops not only cause environmental contamination but loss of agriculture chemicals by lower deposition efficiency. For the purpose of improvement of these problems, this experiment proposes SS attachment type electrostatic induction spraying apparatus with DC power which improves deposition efficiency of agriculture chemicals on the crops.

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에어분사구 설치에 따른 폴리우레아 도막 방수·방식재의 비산 발생 저감에 관한 연구 (A study on the Reduction of Scattering of Polyurea Coating for Waterproofing and Anti-Corrosion by Installing Air Jet Nozzle)

  • 김선도;박완구;박진상;조일규;김병일;오상근
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2017년도 춘계 학술논문 발표대회
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    • pp.236-237
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    • 2017
  • This study discusses the development of waterproofing layer jet-spray nozzle that forms a three-dimensional air cell. This nozzle has an air flow generation mechanism in the air groove of the attachment cell part located at the end of the injection nozzle. Since the air grooves also function as an air curtain, the airborne particles generated when the waterproof material is sprayed is effectively blocked. In the past, spraying of the waterproof material through the high pressure was possible, but this technology allows stable injection due to the static agitation method, and various problems caused by particle generation has been (damages to neighboring areas, economic loss, etc.) minimized.

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축류홴 익단누설와류의 수치적 해석 (Numerical Analysis of a Tip Leakage Vortex in an Axial Flow Fan)

  • 장춘만;김광용
    • 유체기계공업학회:학술대회논문집
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    • 유체기계공업학회 2003년도 유체기계 연구개발 발표회 논문집
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    • pp.404-411
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    • 2003
  • Three-dimensional vortical flow and separated flow topology near the casing wall in an axial flow fan having two different tip clearances have been investigated by a Reynolds-averaged Wavier-Stokes (RANS) flow simulation. The simulation shows that the tip leakage vortex formed close to the leading edge of the blade tip on suction side grows in the streamwise direction. On the casing wall, a separation line is formed upstream of the leakage vortex center due to the interference between the leakage vortex and main flow. The reverse flow is observed between the separation line and the attachment line generated downstream of the trailing edge, and increased with enlarging tip clearance. The patterns of a leakage velocity vector including a leakage flow rate are also analyzed according to two tip clearances. It is noted that the understanding of the distribution of a limiting streamline on the casing wall is very important to grasp the characteristics of the vortical flow in the axial flow fan.

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이동 노드의 접속점 변경에 따른 IP 데이터그램 유실의 최소화 방안 (A Mechanism for Minimizing Loss of IP Datagrams by Changing in Point-of-Attachment of Mobile Node)

  • 권혜연;박애순;이재경;박종원
    • 한국통신학회논문지
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    • 제26권6A호
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    • pp.998-1007
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    • 2001
  • 이동 IP 지원 환경에서 이동 노드가 방문중인 외부 에이전트를 떠나 새로운 외부 에이전트로 이동하면, 새로운 외부 에이전트에서의 이동 노드는 등록이 완료될 때까지 위치 식별이 어렵게 된다. 따라서 이 동안에 발생하는 이동 노드를 목적지로 하는 데이터그램은 이동 노드에서 전달되지 못하고 유실된다. 본 논문에서는 이러한 이동 노드가 외부 에이전트를 변경하는 중에 발생하는 데이터그램이 유실되지 않도록, 이전의 외부 에이전트가 새로운 외부 에이전트로 해당 데이터그램을 터널링하는 메커니즘에 대해 기술한다. 이 메커니즘은 이동 노드가 등록 과정에서 자신의 변경된 위치를 이전의 외부 에이전트에게 알려주어, 이전의 외부 에이전트가 홈 에이전트로부터 터널링되는 데이터그램을 새로운 외부 에이전트를 통해 이동 노드에게 전달할 수 있도록 한다. 이러한 방법은 인접 외부 에이전트간의 등록과 터널링에 걸리는 시간이 짧으므로, 유실되는 데이터그램의 수를 최소화하고 추가적인 메시지와 확장 필드의 사용을 요구하지 않는다.

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