• 제목/요약/키워드: reverse profile

검색결과 139건 처리시간 0.027초

디젤엔진용 캠의 형상 설계에 관한 연구 (A Study on the Design of Diesel Engine Cam Profile)

  • 이완하;송화섭;홍준희
    • 한국공작기계학회논문집
    • /
    • 제15권3호
    • /
    • pp.104-110
    • /
    • 2006
  • It is a study on the design of a cam profile for diesel engine SOHC. It is used a reverse engineering method without the usual copy processing. It draws up the contour data from an actual cam and processes by CNC. The profile of the cam is reappeared to be up to operational specifications that are the opening and shutting time, lift, speed and acceleration of the inhalation and escape valves. While the cam operating, the noise and vibration are occurred by the sudden change of speed. The new design of cam profile is suitable fur the valve operations to be smooth. We propose the design method of a cam profile far the reappearance of an actual cam. It is proved to be the propriety about the design of the cam profile through the processing, measurement, and comparison of the cam profile.

파노라마방사선 사진에서의 하악과두구조 (THE STRUCTURE OF THE MANDIBULAR CONDYLE IN THE PANORAMIC RADIOGRAPH)

  • 최순철
    • 치과방사선
    • /
    • 제20권2호
    • /
    • pp.163-167
    • /
    • 1990
  • The author has evaluated the panoramic image of the mandibular condyle according to its horizontal condylar angle (0˚, 10˚, 20°, 30°, 40°) and mandibular position (standard, 25㎜ forward and reverse position). The results were as follows: 1. The larger the horizontal condylar angle was, the larger the horizontal magnification was in all positions. 2. In case of small horizontal condylar angle, profile view could be obtained in 25㎜ forward and reverse position. 3. In case of large horizontal condylar angle, profile view could not be obtained in any positions.

  • PDF

레이저 센서를 이용한 신발 내측 측정장치 개발 (Development of an Internal Measurement System for the Footwear using Laser Sensor)

  • 이지용;김민주;이승수;박재덕;전언찬
    • 한국정밀공학회:학술대회논문집
    • /
    • 한국정밀공학회 2004년도 추계학술대회 논문집
    • /
    • pp.281-284
    • /
    • 2004
  • This paper presents studies on the development of an internal measurement system for the footwear using laser sensor. The measurement system gains to the height of the profile at internal footwear. It accomplishes the 3-axises control which uses ball screws, L-M guides and stepping motors. It is used a laser sensor at the measurement of the distance, and Labview is used for the control and the measurement. We can get the profile through reverse engineering for the LAST. The data of profile is fixed a heigh of the LAST. Then, we try to verify as compare the profile with one which is collected by Internal measurement system..

  • PDF

지상LiDAR를 이용한 터널의 Reverse Engineering (Tunnel Reverse Engineering Using Terrestrial LiDAR)

  • 조형식;손홍규;김종석;이석군
    • 대한토목학회논문집
    • /
    • 제28권6D호
    • /
    • pp.931-936
    • /
    • 2008
  • 지상LiDAR는 토탈스테이션에 비해 신속한 측량이 가능하기 때문에 터널의 내공단면 측량을 적기에 수행하고 중심선 오차와 여 미굴량 발생을 최소화할 수 있는 강점을 가지고 있어 지상LiDAR를 이용한 터널의 내공단면 측량 및 계측이 점점 증대되고 있으며 보다 효율적이고 정확한 지상LiDAR 활용을 위한 연구도 활발하게 진행 중이다. 현재 일반적으로 터널의 여 미굴량을 계산할 때 사용되는 양단면 평균법의 경우 기존 측량 방식인 토탈스테이션 및 사진측량 등과의 비교는 많이 이루어졌으나 터널 전체의 3차원 위치정보를 얻을 수 있는 지상LiDAR를 이용하여 터널의 내공단면을 측량 체적 및 여 미굴량을 구할 때 관측간격에 따른 기준이 없는 실정이다. 이에 본 연구에서는 시험터널에 대한 reverse engineering을 실시하여 터널 내공단면 측량 시 터널단면의 체적을 비교하여 가장 합리적인 간격을 결정하고 이 결과를 토대로 현재 설계 데이터가 존재하지 않는 시험터널에 대한 CAD도면을 제작하였다. 또한 지상LiDAR 기술의 정확도를 검증하기 위하여 토탈스테이션과의 비교를 통하여 타겟좌표 정확도, 입사각에 따른 정확도 분석을 실시하였다.

축류형 터빈 익형의 역설계 및 형상설계를 위한 설계변수에 관한 연구 (Study of Reverse Design for an Axial Turbine Blade Profile and Design Parameters for Designing Blade Geometry)

  • 조수용;오군섭;최범석
    • 한국유체기계학회 논문집
    • /
    • 제3권2호
    • /
    • pp.7-14
    • /
    • 2000
  • For a given axial turbine blade, reverse design method is developed to improve blade efficiency, optimize blade profile, or repair parts etc. In this process, design parameters for designing axial turbine blade are induced. The induced design parameters are as follows; ellipse at leading edge, radios of trailing edge, axial chord, tangential chord, wedge angle at the inlet, and unguided turning angle. Suction and pressure surfaces of turbine blade are described by cubic polynomials. Two sample blades we chosen and their blade profiles are measured at the mean radius. Values of design parameters for sample blades are obtained by the reverse design method. Re-designed blade profiles using calculated design parameters are compared with the measured data, and they show good agreement. So, the developed design method could be applied to design general turbine blades. Various blade shapes are designed, and they show that designed blade profiles can be adjusted by controlling design parameters.

  • PDF

Load deformation characteristics of shallow suspension footbridge with reverse profiled pre-tensioned cables

  • Huang, Ming-Hui;Thambiratnam, David P.;Perera, Nimal J.
    • Structural Engineering and Mechanics
    • /
    • 제21권4호
    • /
    • pp.375-392
    • /
    • 2005
  • Cable supported structures offer an elegant and economical solution for bridging over long spans with resultant low material content and ease of construction. In this paper, a model of shallow cable supported footbridge with reverse profiled pre-tensioned cables is treated and its load deformation characteristics under different quasi-static loads are investigated. Effects of important parameters such as cable sag and pre-tension are also studied. Numerical results performed on a 3D model show that structural stiffness of this bridge (model) depends not only on the cable sag and cross sectional areas of the cables, but also on the pre-tension in the reverse profiled cables. The tension in the top supporting cables can be adjusted to a high level by the pre-tension in the reverse profiled bottom cables, with the total horizontal force in the bridge structure remaining reasonably constant. It is also evident that pre-tensioned horizontally profiled cables can greatly increase the lateral horizontal stiffness and suppress the lateral horizontal deflection induced by eccentric vertical loads.

역회전 편심 운동 방식에 의한 비구면 유리렌즈 금형의 공구마크 제거 방법에 관한 연구 (Tool Mark Removal Method of Aspherical Glass tens Mold by Reverse-rotational Eccentric Motion)

  • 이호철;김중억;강현형;김동식
    • 소성∙가공
    • /
    • 제18권2호
    • /
    • pp.172-176
    • /
    • 2009
  • In this paper, new aspherical surface polishing mechanism is suggested to polish aspherical glass lens mold by both airbag polishing tool and reverse-rotational eccentric motion. Up to now, conventional aspherical lens polishing method by the small tool polishing uses the aspherical surface profile and the trajectory of the polishing tool is also controlled. However, full contact concept by airbag polishing tool and no position control make the easy polishing setup and does not need aspherical design profile. An aspherical lens polishing machine was made for this study and a tool mark removal experiment fur the fine-grounded lens mold was successfully performed.

유정압테이블의 정밀도향상을 위한 수정가공 알고리즘 (Corrective machining Algorithm for Improving the Motion Accuracy of Hydrostatic Table)

  • 박천홍;이찬홍;이후상
    • 한국정밀공학회:학술대회논문집
    • /
    • 한국정밀공학회 1997년도 추계학술대회 논문집
    • /
    • pp.380-384
    • /
    • 1997
  • For improving the motion accuracy of hydrostatic table, corrective machining algorithm is proposed in this paper. The algorithm consists of three main processes. Reverse analysis is performed firstly to estimate rail profile from measured linear and angular motion error, in the algorithm. For the next step, correctwe machining information is decided as referring to the estimating rail profile. Finally, motion errors on correctively machined rail are analized by using motion error analysls method proposed in the previous paper. These processes can be rtcrated if the analized motion errors are worse than target accuracy. In order to verify the validity of the algorithm theoretically, motion errors by the estimated rail after corrective machining are compared with motion errors by true rail assumed as the measured value. Estimated motion errors show good agreement with assumed values, and it is confirmed that the algorithm IS effective to acquire the corrective machming information to improve the accuracy of hydrostatic table.

  • PDF

Reverse Takotsubo cardiomyopathy with left bundle branch block after anesthesia induction in a patient with subarachnoid hemorrhage: a case report

  • Choi, Eun Kyung;Kim, Jong-Hoon;Kim, Minhyun
    • Journal of Yeungnam Medical Science
    • /
    • 제39권2호
    • /
    • pp.172-177
    • /
    • 2022
  • Takotsubo or reverse Takotsubo cardiomyopathy is a well-known cardiac complication of subarachnoid hemorrhage (SAH) that shows transient left ventricular wall motion abnormalities with electrocardiogram (ECG) changes. ST change followed by T inversion is a common ECG finding complicated with these disorders, left bundle branch block (LBBB) may be a potential ECG pattern which is seen. In this case, we describe the clinical profile and outcomes of a patient with LBBB and reverse Takotsubo cardiomyopathy after anesthetic induction, which was scheduled as an emergent external ventricular drainage after SAH. This is the first report of an LBBB pattern in reverse Takotsubo cardiomyopathy.

Toxicity Evaluation of a Non-Pain Pharmacopuncture Extract Using a Bacterial Reverse Mutation Test

  • Ji Hye Hwang;Chul Jung
    • 대한약침학회지
    • /
    • 제27권2호
    • /
    • pp.154-161
    • /
    • 2024
  • Objectives: The objective of this study was to assess the genotoxicity of a no-pain pharmacopuncture (NPP) extract developed in 2022 using a bacterial reverse mutation assay, aiming to further substantiate the safety profile of NPP. Methods: The genotoxicity evaluation involved a bacterial reverse mutation assay to assess the mutagenic potential of NPP extracts with and without metabolic activation. Histidine-requiring Salmonella typhimurium strains (TA98, TA100, TA1535, and TA1537) and tryptophan-requiring Escherichia coli strains (WP2uvrA) were used in the assay. Results: The NPP extract did not induce a revertant colony count exceeding two times that of the negative control at any dose level in any of the tested strains, both with and without metabolic activation. Additionally, no growth inhibition or precipitation was observed in the presence of NPP. Conclusion: Based on the findings, it can be concluded that the NPP extract exhibited no mutagenic potential in the in vitro genotoxicity tests conducted.