• Title/Summary/Keyword: three dimensional measurement

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Construction and Measurement of Three-Dimensional Knee Joint Model of Koreans (한국인의 3차원 무릎관절 구축 및 형상 측정)

  • Park, Ki-Bong;Kim, Ki-Bum;Son, Kwon;Suh, Jeung-Tak;Moon, Byung-Young
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.28 no.11
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    • pp.1664-1671
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    • 2004
  • It is necessary to have a model that describes the feature of the knee Joint with a sufficient accuracy. Koreans, however, do not have their own knee joint model to be used in the total knee replacement arthroplasty. They have to use European or American models which do not match Koreans. Three-dimensional visualization techniques are found to be useful in a wide range of medical applications. Three-dimensional imaging studies such as CT(computed tomography) and MRI(magnetic resonance image) provide the primary source of patient-specific data. Three-dimensional knee joint models were constructed by image processing of the CT data of 10 subjects. Using the constructed model, the dimensions of Korean knee joint were measured. And this study proposed a three-dimensional model and data, which can be helpful to develop Korean knee implants and to analyze knee joint movements.

A reliability measure of three dimensional shapes based on statistical shape analysis (통계적 형상분석을 이용한 3차원 형상의 신뢰도 계수)

  • Shin, Sang Min
    • The Korean Journal of Applied Statistics
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    • v.32 no.1
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    • pp.15-27
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    • 2019
  • The reliability of the data means the overall consistency of the measurement results. Methods for evaluating reliability have been continuously studied because it affects the results of the statistical analysis. Cronbach's ${\alpha}$ coefficient or intraclass correlation coefficient is used for reliability evaluation; however, these measures cannot be applied to data consisting of three-dimensional coordinates to represent an object. In this study, we propose a measure to evaluate the reliability of three dimensional shapes based on statistical shape analysis that is made possible by extracting the shape information from the measured three dimensional coordinates and decomposing the shape variation.

Analysis of Temperature and Total Heat of Heated Glass through Experimental Measurement and Three-Dimensional Steady-State Heat Transfer Analysis (실측실험과 3차원 정상상태 열전달 해석을 통한 발열유리의 온도 및 전열량 분석)

  • Lee, Do-Hyung;Yoon, Jong-Ho;Oh, Myeong-Hwan
    • KIEAE Journal
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    • v.15 no.1
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    • pp.111-116
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    • 2015
  • Heat loss from windows and condensation occuring on its surface due to its lower insulation value causes much discomfort to occupants. In this study, Heated glass was used to make a basic study on prevention of condensation on glass surface for its heating functionality through experimental measurement and simulation analysis of total heat flux on the interior and exterior surface of glass. Error between experimental results and three dimensional steady-state heat transfer analysis were caused firstly, beacuse in the experimental chambers, cold chamber and steady temperature and humidity chamber, air temperature setting was not constant but rather ON/OFF control, and secondly, due to error rate in heat flux meter due to heat flux direction even in stable conditions.

A Study on the Calculation of the Area through the Three Dimensional Terrain Model (3차원 지형모델을 이용한 면적산출에 관한 연구)

  • 강인준;장용구;김상석;김윤수
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.20 no.2
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    • pp.111-118
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    • 2002
  • These days, surveying instruments are developing rapidly and the precision is improving continuously. The building of three dimensional terrains of high precision are possible and the calculation of the areas or the volumes have high precision due to the development of the technique of the spatial information system using computer. But actually, in construction site they calculate two-dimensional area using the traditional method, plate table surveying, planimeter, and then get three-dimensional area through multiplying two-dimensional area by the slope correction factor. In this study, we show the defect and inefficiency of the calculation of area by the traditional methods and survey the area with Electric Distance Measurement and GPS instrument. With this data, we made the three dimensional terrain model and calculated two-dimensional area, three-dimensional area. After that, we compared areas that calculated by algorithm of triangulated irregular network and analysis of grid method with standard area that calculated by the traditional method. Finally, this paper suggested more effective and precious method in calculating three-dimensional area.

A Study on the Development of a method for estimating the amount of gate opening discharge in estuary using the three-dimensional fixed measurement of flow data for Integrated Nakdong-river estuary management (낙동강하굿둑 통합관리를 위한 3차원 고정식 유량 측정 자료를 이용한 하굿둑 개도 방류량 산정 기법 개발)

  • Kang, Dukee;Seo, Yongjae;Lim, Kyoungmo;Park, Byeong Woo
    • Journal of Wetlands Research
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    • v.24 no.1
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    • pp.52-58
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    • 2022
  • Recently, various efforts and research are being conducted to integrated management of the estuary in Nakdong River. As one of such studies, measurement of opening discharge amount for each floodgate using a three-dimensional fixed ultrasonic flow meter is being conducted, but studies on hydraulic and statistical processing procedures and techniques using actual measurement results for calculating discharge amount by opening remain at the basic level. Therefore, in this study, a data processing technique using three-dimensional fixed ultrasonic flow meter measurement data was developed, the flow coefficient was calculated based on the measured data, and the applicability of the discharge amount calculation formula development was reviewed.

Development of Simulation Model for Diffusion of Oil Spill in the Ocean (III) - Oil-droplet spreading measurement using 3-dimensional digital image processing technique- (해양유출기름의 확산 시뮬레이션 모델개발 (III) -3차원 디지털화상처리를 이용한 유적의 퍼짐 계측 -)

  • 이중우;도덕희;김기철;강신영
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.6 no.1
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    • pp.47-55
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    • 2000
  • A three-dimensional digital image processing technique is proposed to quantitatively predict the dispersion phenomena of oil droplet onto the surface of the water. This technique is able to get the dispersion rate of an oil droplet three-dimensionally just below the surface of the water over time. The obtained dispersion rate obtained through this technique is informative to the investigation into the relationship among the gravity, surface tensions between oil, water, and air. This technique is based upon the three-dimensional PIV(Particle Imaging Velocimetry) technique and its system mainly consists of a three CCD(Charge Coupled Device) cameras, an image grabber, and a host computer in which an image processing algorithm is adopted for the acquisition of dispersion rate oil an oil droplet.

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Three-dimensional vibration measurement algorithm using one laser scanning vibrometer (한대의 LSV 를 이용한 3 차원 진동측정방법)

  • Kim, Dong-Kyu;Song, Ha-Jun;Park, Kyi-Hwan
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2012.04a
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    • pp.935-939
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    • 2012
  • 3D vibration measurement is achieved using one laser scanning vibrometer(LSV) and Laser scanner(LS) by moving the LSV to three arbitrarily locations from the principle that vibration analysis based on the frequency domain is independent of the vibration signal based on time domain. The proposed system has the same effect as using three sets of LSVs. It has an advantage of reducing equipment costs. Analytical approach of obtaining in-plane and out-of-plane vibration of surface is introduced using geometrical relations between three LSV coordinates and vibration measured at three different locations.

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Three-Dimensional Characterization of Strong Recirculating Flow by Stereoscopic PIV

  • Ikeda, Yuji;Palero, Virginia;Sato, Kei;Nakajima, Tsuyoshi
    • Journal of the Korean Society of Combustion
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    • v.7 no.1
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    • pp.37-43
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    • 2002
  • Spray characteristics in the swirling flow were investigated by Stereoscopic PIV. Spatial spray structures were measured by PIV as well as PDA in order to understand stable flame stabilization. The feasibility study of Stereoscopic PIV in spray flame was also demonstrated. The size and location of recirculation flow were measured. The stereoscopic PIV could provide 3-D flow fluctuation that cannot be measured by convectional measurement systems.

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A Study on the Measurement of an Object with Grid Pattern (격자 무늬를 지닌 3차원 물체의 측정에 관한 연구)

  • 안정호
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1995.04b
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    • pp.485-489
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    • 1995
  • From the relationship between the two different views of an object with grid, the three dimensional coordinates of intersection points are determined. The images are captured and digitized with a CCD camera and a frame grabber. To find intersection points, local thresholding and line thinning operations are performed. By establishing the correspondence between the points in the two views, the three dimensional corrdinates of intersection points are calculated.

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