• 제목/요약/키워드: Precise parts

검색결과 318건 처리시간 0.034초

영상검지 카메라를 이용한 도로상의 차량흐름 계측방안 연구 (The Development of Camera Detection System for the Measurement Road Traffic Data)

  • 김희식;김진만
    • 한국안전학회지
    • /
    • 제18권4호
    • /
    • pp.23-27
    • /
    • 2003
  • To improve the road transportation safety, the road traffic data is monitored by applying an image detection system. The road traffic safety is analysed using image processing techniques. For more accurate measurement, the coordinate matching of real road data to image is one of the most essential parts of the image detection technique. The road image is skewed at the input screen, because the video camera is installed at the roadside. A fast and precise algorithm for the coordinate matching is developed to convert image coordinates into road coordinates.

항공기 부품의 생산 및 정비를 위한 공정 계획 시스템의 개발 (Development of a CAPP System for Production and Maintenance of Aircraft Parts)

  • 노경윤;강수준
    • 한국군사과학기술학회지
    • /
    • 제2권2호
    • /
    • pp.83-91
    • /
    • 1999
  • Dynamic characteristic of manufacturing stage is understood and the utilization of each machine is maximized by developing on-line dynamic CAPP system to consider the overloads in the aircraft part manufacturing line. In this paper, a scheme of production planning and scheduling system was proposed through inspection about some predeveloped CAPP system. Developed production planning and scheduling system included process planning module. After precise inspection of some FMS line schema at domestic heavy industry, optimized FMS line was applied to aircraft part manufacturing and repairing factory. By virtue of considering overloads of factory and machine through on-line dynamic CAPP system, the utilization of resources is maximized and manufacturing lead time is minimized.

  • PDF

자유단조공정에서 기공폐쇄 예측을 위한 유한요소해석 (FEM Analysis for the Prediction of Void Closure On the Open Die Forging Process)

  • 민규영;임성주;최호준;최석우;박용복
    • 한국소성가공학회:학술대회논문집
    • /
    • 한국소성가공학회 2008년도 춘계학술대회 논문집
    • /
    • pp.71-74
    • /
    • 2008
  • In order to resolve the problems which appear after the clean large ingot production process, the impurities which are involved in the steel smelting process should be removed by developing cleaner materials. Through the rationalization of cogging process that is the first forging process of large ingot the quality is to be improved. For the sake of the optimization of an open die forging process and the improvement of the subject matter frequency ratio, a hazard precise die forging process must be developed and a Near Net Shape Forming accomplished. As a result, energy can be reduced by minimizing an after control process. In order to produce large axes and other forming parts, processing techniques are to be developed. In this context, this paper is a study about a reduction ratio, dies width ratio and rotary angles, the amount of overlap, and intends to analysis cogging processes, utilizing Deform-3D cogging module

  • PDF

효율적인 마이크로 버 측정 시스템 개발 (Development of Effective Measurement System for Micro Burrs)

  • 고성림;토호황민
    • 한국정밀공학회:학술대회논문집
    • /
    • 한국정밀공학회 2005년도 추계학술대회 논문집
    • /
    • pp.702-705
    • /
    • 2005
  • Burr is an undesirable projection as result of plastic deformation. Burr minimization and effective deburring process are required strongly to reduce the cost of the parts. In doing these efforts, the precise burr measurement must be provided for the efficient process. For this purpose the conoscopic holography sensors are selected before. However, it has been very difficult to measure micro burrs less than $10{\mu}m$ due to their tiny and sharp geometries as well as the effect of ambient vibration during scanning. A new micro burr measurement system using high precision. Conoprobe sensor and XY table can measure the micro burrs which is less than $10{\mu}m$. Experiments were carried out showing that micro burr around $10{\mu}m$ was successfully measured and analyzed.

  • PDF

Automatic face detection using chromaticity space and deformable templates

  • Lee, Kwansu;Lee, Sung-Oh;Lee, Byung-Ju;Park, Gwi-Tae
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 제어로봇시스템학회 2001년도 ICCAS
    • /
    • pp.28.1-28
    • /
    • 2001
  • An automatic face recognition(AFR) of individuals is a significant problem in the development of computer vision. An AFR consists of two major parts which are detection of face region and recognition process, and the overall performance of AFR is determined by each. In this paper, the face region is acquired using chromaticity space, but this face region is a simple rectangle which doesn´t consider the shape information. By applying deformable templates to the face region, we can locate the position of the eyes in images. With the face region and the eye location information, more precise face region can be extract from the image. Because processing time is critical in real-time system, we use simplified eye templates and the modified energy function for the efficiency. We can get a good detection performance in experiments.

  • PDF

세척제 용매 중독 사례와 국내·외 규제 검토를 통한 할로겐화 용매 세척제 사용의 문제점 고찰 (Review of Problems with Use of Halogenated Cleaning Solvents Revealed through Case Studies of Cleaning Solvent Poisoning and Analysis of Domestic and Overseas Regulations)

  • 이나루;이혜진;정수진;이도희;신아롬
    • 한국산업보건학회지
    • /
    • 제33권4호
    • /
    • pp.517-527
    • /
    • 2023
  • Objectives: We examine cases of chemical poisoning that occurred in the cleaning of metal parts and the regulations on halogenated solvents in other countries and propose regulations necessary to prevent chemical poisoning from halogenated solvents. Methods: We collected cases of chemical poisoning through the website of the Korea Occupational Safety and Health Agency. A review of the literature was conducted focusing on regulations related to halogenated solvents in the United States and the European Union, particularly for cleaning metal parts. Among the Material Safety Data Sheets submitted to the government, MSDS containing eleven substances were extracted to confirm the composition and product use. We investigated cleaning methods for metal parts used in South Korea. For the hazard classification, the European Chemicals Agency or Japan's NITE's website was used. Results: In the case of poisoning, the cleaning methods involving trichloromethane were dipping and dry, which was not found in the literature. It was confirmed that many halogenated solvents and dimethyl carbonate were used for metal cleaning in South Korea. In vapor degreasing using TCE in the USA, even if the facility is strictly managed, such as by installing cooling coils in open cleaning facilities, the risk of exposure to TCE is considered to be not only carcinogenic but also a concern for acute and chronic effects. In comparison, exposure through Korean work methods such as dipping and drying operations is inevitably much higher. Conclusions: The transition to water-based cleaning with low-hazard chemicals should be a priority in the cleaning process. In the case of metal parts that require precise cleaning, if the use of a halogenated solvent is inevitable, a closed degreasing facility should be used to minimize exposure. The current regulations in the Occupational Safety and Health Act, the Chemical Substances Control Act, and the Air Environment Conservation Act do not require cleaning facilities to minimize emissions. To protect the health of workers using halogenated solvents to clean metal parts, regulations that require a fundamental reduction in exposure will be necessary.

한반도 일원의 중력측정 및 보정의 정밀화와 고밀도 부우게이상 (On the Improvement of Precision in Gravity Surveying and Correction, and a Dense Bouguer Anomaly in and Around the Korean Peninsula)

  • 신영홍;양철수;옥수석;최광선
    • 한국지구과학회지
    • /
    • 제24권3호
    • /
    • pp.205-215
    • /
    • 2003
  • 정밀하고 밀도 높은 부우게이상자료는 지구물리학과 물리측지학적인 측면에서 중요한 기초자료가 된다. 이를 위해서 정밀한 절대중력기준점망의 설치외에도 두 가지 측면을 고려해야 하는데, 하나는 중력측정과 보정의 정밀도를 향상시키는 것이며, 다른 하나는 측점의 밀도를 높이는 일이다. 중력측정에서 GPS를 어떻게 적절히 이용할 것인가에 대해서 알아보았는데, 40km이내의 기선거리에서 두 대의 측지용 GPS수신기를 이용하면, 5분간의 GPS측정으로도 충분하다고 여겨진다. 이 경우 PNU95 지오이드모델과 같은 정밀한 지오이드모델을 사용하여야 한다, 이 방법을 적용함으로써, 비용 및 시간과 인력을 줄일 수 있을 뿐만 아니라 질적인 측면에서도 향상을 가져온다. 또 교점오차를 보정하고 지형효과를 정밀하게 계산하기 위해 컴퓨터 프로그램을 개발했다. 중력탐사에서 같은 지점에서 중복 측정하는 것은 스프링의 변이를 보정하는 것뿐만 아니라 망조정을 적용함으로써 결과들에 대해 통계적으로 접근하는 것을 가능하게 한다. 그럼으로써 다양한 원인에 기인한 큰 오차를 쉽게 찾아내고 보정하여 자료의 질을 향상시킬 수 있으며, 또한 측정의 질을 평가할 수 있다. 최근의 컴퓨터 기술과 디지털 고도자료의 발달도 좀더 정밀한 지형보정을 사용하여 부우게이상의 질을 향상하도록 우리를 고무하고 있다. 본 연구에서는 육상중력, 선상중력, 북한의 부우게이상도, 일본의 중력자료, 고도위성자료, EGM96 지오포텐셜 자료 등, 다양한 중력자료를 입수하였다. 따라서, 이들 자료를 계산하고 편집하여 한반도 일원의 정밀 부우게이상도를 작성할 수 있었는데, 이것은 지구물리학과 물리측지학의 응용에 유용한 자료가 될 것이다.

Ultrahigh Vacuum Technologies Developed for a Large Aluminum Accelerator Vacuum System

  • Hsiung, G.Y.;Chang, C.C.;Yang, Y.C.;Chang, C.H.;Hsueh, H.P.;Hsu, S.N.;Chen, J.R.
    • Applied Science and Convergence Technology
    • /
    • 제23권6호
    • /
    • pp.309-316
    • /
    • 2014
  • A large particle accelerator requires an ultrahigh vacuum (UHV) system of average pressure under $1{\times}10^{-7}$ Pa for mitigating the impact of beam scattering from the residual gas molecules. The surface inside the beam ducts should be controlled with an extremely low thermal outgassing rate under $1{\times}10^{-9}Pa{\cdot}m^3/(s{\cdot}m^2)$ for the sake of the insufficient pumping speed. To fulfil the requirements, the aluminum alloys were adopted as the materials of the beam ducts for large accelerator that thanks to the good features of higher thermal conductivity, non-radioactivity, non-magnetism, precise machining capability, et al. To put the aluminum into the large accelerator vacuum systems, several key technologies have been developed will be introduced. The concepts contain the precise computer numerical control (CNC) machining process for the large aluminum ducts and parts in pure alcohol and in an oil-free environment, surface cleaning with ozonized water, stringent welding process control manually or automatically to form a large sector of aluminum ducts, ex-situ baking process to reach UHV and sealed for transportation and installation, UHV pumping with the sputtering ion pumps and the non-evaporable getters (NEG), et al. The developed UHV technologies have been applied to the 3 GeV Taiwan Photon Source (TPS) and revealed good results as the expectation. The problems of leakage encountered during the assembling were most associated with the vacuum baking which result in the consequent trouble shootings and more times of baking. Then the installation of the well-sealed UHV systems is recommended.

Solution and Estimate to the Angular Velocity of INS Formed only by Linear Accelerometers

  • Junwei, Wu;Jinfeng, Liu;Yunan, Zhang;Na, Yuan
    • 한국항해항만학회:학술대회논문집
    • /
    • 한국항해항만학회 2006년도 International Symposium on GPS/GNSS Vol.1
    • /
    • pp.103-107
    • /
    • 2006
  • At present, most efforts tend to develop a INS which is only based linear accelerometers, because of the low cost micro-machining gyroscopes lack of the accuracy needed for precise navigation application and possible achieving the required levels of precise for micro-machining accelerometer. Although it was known in theory that a minimum of six accelerometers are required for a complete description of a rigid body motion, and any configuration of six accelerometers (except for a "measure zero " set of six-accelerometer schemes) will work. Studies on the feasible configuration of GF-INS indicate that the errors of angular velocity resolved from the six accelerometers scheme are diverged with time or have multi solutions. The angular velocity errors are induced by the biases together with the position vectors of the accelerometers, therefore, in order to treat with the problem just mentioned, researchers have been doing many efforts, such as the extra three accelerometers or the magnetometers may be taken as the reference information, the extended Kalman filter (EKF) involved to make the angular velocity errors bound and be estimated, and so on. In this paper, the typical configurations of GF-INS are introduced; for each type GF-INS described, the solutions to the angular velocity and the specific force are derived and the characteristic is indicated; one of the corresponding extend Kalman filters are introduced to estimate the angular errors; parts of the simulation results are presented to verify the validity of the equations of angular velocity and specific force and the performance of extend Kalman filter.

  • PDF

산업사진측량기법을 이용한 항공기 변형 측정 (Aircraft Deformation Measurement using Industrial Photogrammetry)

  • 이재기;정성혁;유정흠
    • 한국측량학회지
    • /
    • 제23권2호
    • /
    • pp.205-210
    • /
    • 2005
  • 산업이 발달됨에 따라 산업 제품들은 대형화되고 더욱 정밀화 되고 있다. 생산자들은 제품이 요구에 맞게 정밀하게 제작되었는가를 확인할 수 있는 방법이 필요하게 되었고 이러한 이유로 대상물에 접촉을 하지 않으면서 신속하고 정밀한 데이터를 취득할 수 있는 산업사진측량기법이 관심을 끌게 되었다. 따라서 본 연구에서는 산업제품들의 정밀도를 검사하기 위한 방법으로 산업사진측량의 적용성을 알아보기 위하여 O-2A 항공기를 대상으로 실험을 실시하였다. 항공기의 정렬상태를 확인하기 위한 검사점사이의 거리 측정과 변형이 발생하였을 것으로 추정되는 부분의 변형량을 프로젝트 타겟을 이용하여 변형량을 정량적으로 해석함으로써 항공기 정비 및 사고분석 등에 필요한 데이터를 신속히 제공할 수 있었다.