• Title/Summary/Keyword: Shape Estimation

Search Result 983, Processing Time 0.027 seconds

Visualization of Delamination Region in Concrete Structures using Mode Shapes of Delaminated Concrete Section (II) : Impact-Echo Test (박리된 콘크리트의 진동 모드 형상을 이용한 콘크리트 구조물 박리 손상 영역 가시화 (II) : 충격-반향 시험)

  • Oh, Taekeun;Shin, Sung Woo
    • Journal of the Korean Society of Safety
    • /
    • v.28 no.6
    • /
    • pp.36-41
    • /
    • 2013
  • Previous study showed that delamination region in concrete structures can be successfully visualized using mode shapes of delaminated concrete section. However, modal tests for this purpose to obtain mode shapes of the delaminated concrete section may not be applicable in practice since, to correctly obtain the mode shapes of the section, the location and the shape of the delamination region in a structure should be known in advance. Unfortunately those are normally unknown in a real structure. Therefore, a moving forward test method may be useful to obtain the mode shapes of the concrete section when the location and the shape of the delamination region are not known. In this study, impact-echo testing based mode shape estimation technique is proposed and experimentally validated for visualization of delamination region.

Psychophysical Experiment for Shape Recognition by Vibratory Tactile Stimulated Array (진동자극배열에 의한 형상 인식의 정신물리학적 실험)

  • Yoon Myoung-Jong;Kim Nam-Gyun;Yu Kee-Ho
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.11 no.11
    • /
    • pp.943-949
    • /
    • 2005
  • For the psychophysical experiment of tactile perception of shapes, experimental system consists of vibrator, tactile stimulation array, measurement and control system is designed and prepared. The psychophysical experiment for the tactile perception of shape is carried out by the estimation of the subject group. Through the experiment the threshold of tactile perception to multi-stimuli with some line shape is obtained. Also the appropriate tactile stimulus intensity and frequency of the tactile stimulation array to recognize arbitrary shapes effectively are derived and discussed.

CONIFER FOREST BIOMASS ESTIMATION USING MULTI ANGLE SPECTRUM OBSERVATION

  • Kajiwara, Koji;Ono, Yuhsaku;Honda, Yoshiaki
    • Proceedings of the KSRS Conference
    • /
    • 2008.10a
    • /
    • pp.394-397
    • /
    • 2008
  • This research aimed at developing a technique for estimating the tree height using BRF (Bi-directional Reflectance Factor) through the clarification of the relation between shape of the tree crown and the tree height and the relations between the shape of the tree crown and BRF. This paper, reports the results of analyses of data acquired by field measurements done to clarify relation between crown shape and tree height.

  • PDF

An Analytical Study on the Preheating Effect of Workpiece with Cylindrical Shape for 3-Dimensional Laser-Assisted Milling (3 차원 레이저 보조 밀링을 위한 실린더형 시편의 예열효과에 관한 해석적 연구)

  • Woo, Wan-Sick;Lee, Choon-Man
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.32 no.2
    • /
    • pp.173-178
    • /
    • 2015
  • Laser-assisted machining (LAM) is an effective machining method for processing difficult-to-cut materials. Prediction and estimation of preheating effect of the LAM is difficult because of moving heat source. So it is necessary to study the preheating effect of the laser heat source irradiated on the curved surfaces of workpieces of various shape. In this paper, thermal analysis of the LAM for 3-dimentional workpiece with cylindrical shape was performed. The results of this analysis can be applied to obtain the optimal preheating method and path for LAM of 3-dimensional workpiece.

Landscape Design Method of Bridges and Visual Safety Estimation of Structural Shape (교량의 경관설계 방법과 구조형상의 시각적 안전성 평가)

  • Yang, Seung Hyoun;Shiomi, Hiroyuki
    • Journal of the Korea institute for structural maintenance and inspection
    • /
    • v.2 no.3
    • /
    • pp.235-244
    • /
    • 1998
  • In the design of bridges, the points of concem are the landscape design, the function, safety and economical efficiency. But most of studies have been performed on structural engineering. The study on the landscape design of bridges has not been done in korea. Therefore, in this research, the design method of bridges by the judgement of structural engineering and landscape engineering has been proposed, through the process to decide the shape of bridges. Also, the research studies a problem about the visual safety of the structural shape in the landscape design of bridges. The visual experiments applied to the seven models about the shape of hunch in bridge pier. The experiment was made in moving velocity of view point, steady looking time and track of eyeball movement.

  • PDF

Facial Feature Extraction with Its Applications

  • Lee, Minkyu;Lee, Sangyoun
    • Journal of International Society for Simulation Surgery
    • /
    • v.2 no.1
    • /
    • pp.7-9
    • /
    • 2015
  • Purpose In the many face-related application such as head pose estimation, 3D face modeling, facial appearance manipulation, the robust and fast facial feature extraction is necessary. We present the facial feature extraction method based on shape regression and feature selection for real-time facial feature extraction. Materials and Methods The facial features are initialized by statistical shape model and then the shape of facial features are deformed iteratively according to the texture pattern which is selected on the feature pool. Results We obtain fast and robust facial feature extraction result with error less than 4% and processing time less than 12 ms. The alignment error is measured by average of ratio of pixel difference to inter-ocular distance. Conclusion The accuracy and processing time of the method is enough to apply facial feature based application and can be used on the face beautification or 3D face modeling.

Objective Bayesian Estimation of Two-Parameter Pareto Distribution (2-모수 파레토분포의 객관적 베이지안 추정)

  • Son, Young Sook
    • The Korean Journal of Applied Statistics
    • /
    • v.26 no.5
    • /
    • pp.713-723
    • /
    • 2013
  • An objective Bayesian estimation procedure of the two-parameter Pareto distribution is presented under the reference prior and the noninformative prior. Bayesian estimators are obtained by Gibbs sampling. The steps to generate parameters in the Gibbs sampler are from the shape parameter of the gamma distribution and then the scale parameter by the adaptive rejection sampling algorism. A numerical study shows that the proposed objective Bayesian estimation outperforms other estimations in simulated bias and mean squared error.

Repair Cost Estimation Model of the Building Exterior and Outdoor Facilities in Apartment Housing (공동주택 건물 외부공간 및 옥외시설의 공종별 수선비용 산정모델)

  • Lee, Kang-Hee;Chae, Chang-U
    • KIEAE Journal
    • /
    • v.16 no.3
    • /
    • pp.129-135
    • /
    • 2016
  • Purpose: Building figuration is imperative to perceive the its value, environmental clean status and form. Therefore, maintenance activities of the building exterior are required to keep the housing condition and value. Each household should pay the repair cost which is brought out in the future. For this repair cost, the estimation model would needed to forecast and provide the required cost. This study aimed at providing the estimation model of the repair cost, using the repair survey data between the 2011 and 2014 in Seoul. Method: For these, it took various estimation function of repair cost such as 1st function, inverse function and so on. These above functions would be applied into the building exterior and outdoor facilities which figure the building shape and characteristics. Result: Results of this study are shown ; First, among 11 estimation models, the power function has a better statistics and goodness-of-fit than any other models. Second, the estimation model with a variable of household has a pattern in upward to the right. On the contrary, the model with management area is little downward to the right. Both of them are depended on the estimated parameter of the power function and the parameter smaller than 1.

Vehicle Orientation Estimation by Using Magnetometer and Inertial Sensors (3축 자기장 센서 및 관성센서를 이용한 차량 방위각 추정 방법)

  • Hwang, Yoonjin;Choi, Seibum
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.24 no.4
    • /
    • pp.408-415
    • /
    • 2016
  • The vehicle attitude and sideslip is critical information to control the vehicle to prevent from unintended motion. Many of estimation strategy use bicycle model or IMU integration, but both of them have limits on application. The main purpose of this paper is development of vehicle orientation estimator which is robust to various vehicle state and road shape. The suggested estimator use 3-axis magnetometer, yaw rate sensor and lateral acceleration sensor to estimate three Euler angles of vehicle. The estimator is composed of two individual observers: First, comparing the known magnetic field and gravity with measured value, the TRIAD algorithm calculates optimal rotational matrix when vehicle is in static or quasi-static condition. Next, merging 3-axis magnetometer with inertial sensors, the extended Kalman filter is used to estimate vehicle orientation under dynamic condition. A validation through simulation tools, Carsim and Simulink, is performed and the results show the feasibility of the suggested estimation method.

Estimation of Structural Deformed Shapes Using Limited Number of Displacement Measurements (한정된 계측 변위를 이용한 구조물 변형 형상 추정)

  • Choi, Junho;Kim, Seungjun;Han, Seungryong;Kang, Youngjong
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.33 no.4
    • /
    • pp.1295-1302
    • /
    • 2013
  • The structural deformed shape is important information to structural analysis. If the sufficient measuring points are secured at the structural monitoring system, reasonable and accurate structural deformation shapes can be obtained and structural analysis is possible using this deformation. However, the accurate estimation of the global structural shapes might be difficult if sufficient measuring points are not secure under cost limitations. In this study, SFSM-LS algorithm, the economic and effective estimation method for the structural deformation shapes with limited displacement measuring points is developed and suggested. In the suggested method, the global structural deformation shape is determined by the superposition of the pre-investigated structural deformed shapes obtained by preliminary FE analyses, with their optimum weight factors which lead minimization of the estimate errors. 2-span continuous bridge model is used to verify developed algorithm and parametric studies are performed. By the parametric studies, the characteristics of the estimation results obtained by the suggested method were investigated considering essential parameters such as pre-investigated structural shapes, locations and numbers of displacement measuring points. By quantitative comparison of estimation results with the conventional methods such as polynomial, Lagrange and spline interpolation, the applicability and accuracy of the suggested method was validated.