• Title/Summary/Keyword: 3D Point Data

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A Study of the Electrical Properties of the Buccal Area using Facial Surface Electromyography

  • Choi, Yoo Min;Kim, Jong Uk;Kim, Lak Hyung;Yook, Tae Han
    • Journal of Acupuncture Research
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    • v.34 no.2
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    • pp.75-82
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    • 2017
  • Objectives : The purpose of this study was to determine the electrical properties of the buccal area using facial surface electromyography (sEMG). Methods : This research was conducted on 44 healthy participants irrespective of their sex. Surface electrodes were attached to the midpoints of three imaginary lines connecting ST4 (Dicang) to ST6 (Jiache), ST4 to SI18 (Quanliao), and ST4 to the center point of SI18 and ST6. Then, the participants were trained in the movement that included a comprehensive action of buccal area. While the participants were performing the motion, sEMG values ($E_1$, $E_2$, $E_3$) and the distance change of the three imaginary lines ($D_1$, $D_2$, $D_3$) were measured. The data were statistically analyzed using SPSS ver. 22.0. Results : Significant differences were observed in the distance changes ($D_1$>$D_3$, $D_2$>$D_3$) and sEMG values ($E_1$<$E_2$<$E_3$). Moreover, there were positive correlations between $D_1$ and $E_1$, $D_2$ and $E_2$. Conclusion : We suggest that the measurement at ST4 to the center point of ST6 and SI18 with this motion would be adequate to check the electrical characteristics of the buccal area.

Automation of Building Extraction and Modeling Using Airborne LiDAR Data (항공 라이다 데이터를 이용한 건물 모델링의 자동화)

  • Lim, Sae-Bom;Kim, Jung-Hyun;Lee, Dong-Cheon
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.27 no.5
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    • pp.619-628
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    • 2009
  • LiDAR has capability of rapid data acquisition and provides useful information for reconstructing surface of the Earth. However, Extracting information from LiDAR data is not easy task because LiDAR data consist of irregularly distributed point clouds of 3D coordinates and lack of semantic and visual information. This thesis proposed methods for automatic extraction of buildings and 3D detail modeling using airborne LiDAR data. As for preprocessing, noise and unnecessary data were removed by iterative surface fitting and then classification of ground and non-ground data was performed by analyzing histogram. Footprints of the buildings were extracted by tracing points on the building boundaries. The refined footprints were obtained by regularization based on the building hypothesis. The accuracy of building footprints were evaluated by comparing with 1:1,000 digital vector maps. The horizontal RMSE was 0.56m for test areas. Finally, a method of 3D modeling of roof superstructure was developed. Statistical and geometric information of the LiDAR data on building roof were analyzed to segment data and to determine roof shape. The superstructures on the roof were modeled by 3D analytical functions that were derived by least square method. The accuracy of the 3D modeling was estimated using simulation data. The RMSEs were 0.91m, 1.43m, 1.85m and 1.97m for flat, sloped, arch and dome shapes, respectively. The methods developed in study show that the automation of 3D building modeling process was effectively performed.

Estimating Three-Dimensional Scattering Centers of a Target Using the 3D MEMP Method in Radar Target Recognition (레이다 표적 인식에서 3D MEMP 기법을 이용한 표적의 3차원 산란점 예측)

  • Shin, Seung-Yong;Myung, Noh-Hoon
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.19 no.2
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    • pp.130-137
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    • 2008
  • This paper presents high resolution techniques of three-dimensional(3D) scattering center extraction for a radar backscattered signal in radar target recognition. We propose a 3D pairing procedure, a new approach to estimate 3D scattering centers. This pairing procedure is more accurate and robust than the general criterion. 3D MEMP(Matrix Enhancement and Matrix Pencil) with the 3D pairing procedure first creates an autocorrelation matrix from radar backscattered field data samples. A matrix pencil method is then used to extract 3D scattering centers from the principal eigenvectors of the autocorrelation matrix. An autocorrelation matrix is constructed by the MSSP(modified spatial smoothing preprocessing) method. The observation matrix required for estimation of 3D scattering center locations is built using the sparse scanning order conception. In order to demonstrate the performance of the proposed technique, we use backscattered field data generated by ideal point scatterers.

Development of Deep Learning-based Automatic Classification of Architectural Objects in Point Clouds for BIM Application in Renovating Aging Buildings (딥러닝 기반 노후 건축물 리모델링 시 BIM 적용을 위한 포인트 클라우드의 건축 객체 자동 분류 기술 개발)

  • Kim, Tae-Hoon;Gu, Hyeong-Mo;Hong, Soon-Min;Choo, Seoung-Yeon
    • Journal of KIBIM
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    • v.13 no.4
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    • pp.96-105
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    • 2023
  • This study focuses on developing a building object recognition technology for efficient use in the remodeling of buildings constructed without drawings. In the era of the 4th industrial revolution, smart technologies are being developed. This research contributes to the architectural field by introducing a deep learning-based method for automatic object classification and recognition, utilizing point cloud data. We use a TD3D network with voxels, optimizing its performance through adjustments in voxel size and number of blocks. This technology enables the classification of building objects such as walls, floors, and roofs from 3D scanning data, labeling them in polygonal forms to minimize boundary ambiguities. However, challenges in object boundary classifications were observed. The model facilitates the automatic classification of non-building objects, thereby reducing manual effort in data matching processes. It also distinguishes between elements to be demolished or retained during remodeling. The study minimized data set loss space by labeling using the extremities of the x, y, and z coordinates. The research aims to enhance the efficiency of building object classification and improve the quality of architectural plans by reducing manpower and time during remodeling. The study aligns with its goal of developing an efficient classification technology. Future work can extend to creating classified objects using parametric tools with polygon-labeled datasets, offering meaningful numerical analysis for remodeling processes. Continued research in this direction is anticipated to significantly advance the efficiency of building remodeling techniques.

Phenomenological monte carlo simulation model for predicting B, $BF_2$, As, P and Si implant profiles in silicon-based semiconductor device

  • Kwon, Oh-Kuen;Son, Myung-Sik;Hwang, Ho-Jung
    • Journal of Korean Vacuum Science & Technology
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    • v.3 no.1
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    • pp.1-9
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    • 1999
  • This paper presents a newly enhanced damage model in Monte Carlo (MC) simulation for the accurate prediction of 3-Dimensional (3D) as-implanted impurity and point defect profiles induced by ion implantation in (100) crystal silicon. An empirical electronic energy loss model for B, BF2, As, P and Si self implant over the wide energy range has been proposed for the ULSI device technology and development. Our model shows very good agreement with the SIMS data over the wide energy range. In the damage accumulation, we considered the self-annealing effects by introducing our proposed non-linear recomvination probability function of each point defect for the computational efficiency. For the damage profiles, we compared the published RBS/channeling data with our results of phosphorus implants. Our damage model shows very reasonable agreement with the experiments for phosphorus implants.

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Longitudinal Deformation Profile in Tunnel using Measured Data (계측자료를 이용한 터널의 종단변형도)

  • Jang, Won-Yil;Yang, Hyung-Sik;Chung, So-Keul
    • Tunnel and Underground Space
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    • v.18 no.5
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    • pp.338-342
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    • 2008
  • Longitudinal deformation profile(LDP) has been obtained mostly by numerical analysis. In this study, LDP was plotted by measured data from horizontal inclinometer and crown settlement. Deformation of foe ahead was determined by comparing to the maximum deformation point and deformation of after excavation was determined by regression of the measured crown settlement data. The result shows that crown deformation began as f3r as 3D ahead of the face. Crown settlement at the face was 40% of ultimate deformation, which was 10% higher than numerical results, and the deformation converged after excavation of 4D.

Construction of Multi-Dimensional Ortho-Images with a Digital Camera and the Multi-Image Connection Method (디지털카메라와 다중영상접합법을 이용한 다차원 정사영상의 구축)

  • Kim, Dong Moon
    • Journal of Digital Convergence
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    • v.12 no.8
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    • pp.295-302
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    • 2014
  • Essential to the establishment of such 3D spatial information are the laser scanning technology to obtain high-precision 3D point group data and the photography-metric camera to obtain high-resolution multispectral image information. The photography-metric camera, however, lacks in usability for its broad scope of utilization due to the high purchase price, difficult purchase channel, and low applicability. This study thus set out to investigate a technique to establish multi-dimensional ortho-image data with a single lens reflex digital camera of high speed and easy accessibility for general users. That is, the study remodeled a single lens reflex digital camera and calibrated the remodeled camera to establish 3D multispectral image information, which is the essential data of 3D spatial information. Multi-dimensional ortho-image data were collected by surveying the reference points for stereo photos, taking multispectral shots of the objects, and converting them into ortho-images.

3D Cross-Modal Retrieval Using Noisy Center Loss and SimSiam for Small Batch Training

  • Yeon-Seung Choo;Boeun Kim;Hyun-Sik Kim;Yong-Suk Park
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.18 no.3
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    • pp.670-684
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    • 2024
  • 3D Cross-Modal Retrieval (3DCMR) is a task that retrieves 3D objects regardless of modalities, such as images, meshes, and point clouds. One of the most prominent methods used for 3DCMR is the Cross-Modal Center Loss Function (CLF) which applies the conventional center loss strategy for 3D cross-modal search and retrieval. Since CLF is based on center loss, the center features in CLF are also susceptible to subtle changes in hyperparameters and external inferences. For instance, performance degradation is observed when the batch size is too small. Furthermore, the Mean Squared Error (MSE) used in CLF is unable to adapt to changes in batch size and is vulnerable to data variations that occur during actual inference due to the use of simple Euclidean distance between multi-modal features. To address the problems that arise from small batch training, we propose a Noisy Center Loss (NCL) method to estimate the optimal center features. In addition, we apply the simple Siamese representation learning method (SimSiam) during optimal center feature estimation to compare projected features, making the proposed method robust to changes in batch size and variations in data. As a result, the proposed approach demonstrates improved performance in ModelNet40 dataset compared to the conventional methods.

Development of Unmanned Driving Technologies for Speed Sprayer in Orchard Environment (과수원 환경에서의 방제기 무인주행 기술 개발)

  • Li, Song;Kang, Dongyeop;Lee, Hae-min;An, Su-yong;Kwon, Wookyong;Chung, Yunsu
    • IEMEK Journal of Embedded Systems and Applications
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    • v.15 no.6
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    • pp.269-279
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    • 2020
  • This paper presents the design and implementation of embedded systems and autonomous path generation for autonomous speed sprayer. Autonomous Orchard Systems can be divided into embedded controller and path generation module. Embedded controller receives analog sensor data, on/off switch data and control linear actuator, break, clutch and steering module. In path generation part, we get 3D cloud point using Velodyne VLP16 LIDAR sensor and process the point cloud to generate maps, do localization, generate driving path. Then, it finally generates velocity and rotation angle in real time, and sends the data to embedded controller. Embedded controller controls steering wheel based on the received data. The developed autonomous speed sprayer is verified in test-bed with apple tree-shaped artworks.

3D Depth Camera-based Obstacle Detection in the Active Safety System of an Electric Wheelchair (전동휠체어 주행안전을 위한 3차원 깊이카메라 기반 장애물검출)

  • Seo, Joonho;Kim, Chang Won
    • Journal of Institute of Control, Robotics and Systems
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    • v.22 no.7
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    • pp.552-556
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    • 2016
  • Obstacle detection is a key feature in the safe driving control of electric wheelchairs. The suggested obstacle detection algorithm was designed to provide obstacle avoidance direction and detect the existence of cliffs. By means of this information, the wheelchair can determine where to steer and whether to stop or go. A 3D depth camera (Microsoft KINECT) is used to scan the 3D point data of the scene, extract information on obstacles, and produce a steering direction for obstacle avoidance. To be specific, ground detection is applied to extract the obstacle candidates from the scanned data and the candidates are projected onto a 2D map. The 2D map provides discretized information of the extracted obstacles to decide on the avoidance direction (left or right) of the wheelchair. As an additional function, cliff detection is developed. By defining the "cliffband," the ratio of the predefined band area and the detected area within the band area, the cliff detection algorithm can decide if a cliff is in front of the wheelchair. Vehicle tests were carried out by applying the algorithm to the electric wheelchair. Additionally, detailed functions of obstacle detection, such as providing avoidance direction and detecting the existence of cliffs, were demonstrated.