• Title/Summary/Keyword: Segmentation process

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Determination of Physical Footprints of Buildings with Consideration Terrain Surface LiDAR Data (지표면 라이다 데이터를 고려한 건물 외곽선 결정)

  • Yoo, Eun Jin;Lee, Dong-Cheon
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.34 no.5
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    • pp.503-514
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    • 2016
  • Delineation of accurate object boundaries is crucial to provide reliable spatial information products such as digital topographic maps, building models, and spatial database. In LiDAR(Light Detection and Ranging) data, real boundaries of the buildings exist somewhere between outer-most points on the roofs and the closest points to the buildings among points on the ground. In most cases, areas of the building footprints represented by LiDAR points are smaller than actual size of the buildings because LiDAR points are located inside of the physical boundaries. Therefore, building boundaries determined by points on the roofs do not coincide with the actual footprints. This paper aims to estimate accurate boundaries that are close to the physical boundaries using airborne LiDAR data. The accurate boundaries are determined from the non-gridded original LiDAR data using initial boundaries extracted from the gridded data. The similar method implemented in this paper is also found in demarcation of the maritime boundary between two territories. The proposed method consists of determining initial boundaries with segmented LiDAR data, estimating accurate boundaries, and accuracy evaluation. In addition, extremely low density data was also utilized for verifying robustness of the method. Both simulation and real LiDAR data were used to demonstrate feasibility of the method. The results show that the proposed method is effective even though further refinement and improvement process could be required.

Detection of Collapse Buildings Using UAV and Bitemporal Satellite Imagery (UAV와 다시기 위성영상을 이용한 붕괴건물 탐지)

  • Jung, Sejung;Lee, Kirim;Yun, Yerin;Lee, Won Hee;Han, Youkyung
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.38 no.3
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    • pp.187-196
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    • 2020
  • In this study, collapsed building detection using UAV (Unmanned Aerial Vehicle) and PlanetScope satellite images was carried out, suggesting the possibility of utilization of heterogeneous sensors in object detection located on the surface. To this end, the area where about 20 buildings collapsed due to forest fire damage was selected as study site. First of all, the feature information of objects such as ExG (Excess Green), GLCM (Gray-Level Co-Occurrence Matrix), and DSM (Digital Surface Model) were generated using high-resolution UAV images performed object-based segmentation to detect collapsed buildings. The features were then used to detect candidates for collapsed buildings. In this process, a result of the change detection using PlanetScope were used together to improve detection accuracy. More specifically, the changed pixels acquired by the bitemporal PlanetScope images were used as seed pixels to correct the misdetected and overdetected areas in the candidate group of collapsed buildings. The accuracy of the detection results of collapse buildings using only UAV image and the accuracy of collapse building detection result when UAV and PlanetScope images were used together were analyzed through the manually dizitized reference image. As a result, the results using only UAV image had 0.4867 F1-score, and the results using UAV and PlanetScope images together showed that the value improved to 0.8064 F1-score. Moreover, the Kappa coefficiant value was also dramatically improved from 0.3674 to 0.8225.

Extracting curved text lines using the chain composition and the expanded grouping method (체인 정합과 확장된 그룹핑 방법을 사용한 곡선형 텍스트 라인 추출)

  • Bai, Nguyen Noi;Yoon, Jin-Seon;Song, Young-Jun;Kim, Nam;Kim, Yong-Gi
    • The KIPS Transactions:PartB
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    • v.14B no.6
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    • pp.453-460
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    • 2007
  • In this paper, we present a method to extract the text lines in poorly structured documents. The text lines may have different orientations, considerably curved shapes, and there are possibly a few wide inter-word gaps in a text line. Those text lines can be found in posters, blocks of addresses, artistic documents. Our method based on the traditional perceptual grouping but we develop novel solutions to overcome the problems of insufficient seed points and vaned orientations un a single line. In this paper, we assume that text lines contained tone connected components, in which each connected components is a set of black pixels within a letter, or some touched letters. In our scheme, the connected components closer than an iteratively incremented threshold will make together a chain. Elongate chains are identified as the seed chains of lines. Then the seed chains are extended to the left and the right regarding the local orientations. The local orientations will be reevaluated at each side of the chains when it is extended. By this process, all text lines are finally constructed. The proposed method is good for extraction of the considerably curved text lines from logos and slogans in our experiment; 98% and 94% for the straight-line extraction and the curved-line extraction, respectively.

Depth-Based Recognition System for Continuous Human Action Using Motion History Image and Histogram of Oriented Gradient with Spotter Model (모션 히스토리 영상 및 기울기 방향성 히스토그램과 적출 모델을 사용한 깊이 정보 기반의 연속적인 사람 행동 인식 시스템)

  • Eum, Hyukmin;Lee, Heejin;Yoon, Changyong
    • Journal of the Korean Institute of Intelligent Systems
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    • v.26 no.6
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    • pp.471-476
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    • 2016
  • In this paper, recognition system for continuous human action is explained by using motion history image and histogram of oriented gradient with spotter model based on depth information, and the spotter model which performs action spotting is proposed to improve recognition performance in the recognition system. The steps of this system are composed of pre-processing, human action and spotter modeling and continuous human action recognition. In pre-processing process, Depth-MHI-HOG is used to extract space-time template-based features after image segmentation, and human action and spotter modeling generates sequence by using the extracted feature. Human action models which are appropriate for each of defined action and a proposed spotter model are created by using these generated sequences and the hidden markov model. Continuous human action recognition performs action spotting to segment meaningful action and meaningless action by the spotter model in continuous action sequence, and continuously recognizes human action comparing probability values of model for meaningful action sequence. Experimental results demonstrate that the proposed model efficiently improves recognition performance in continuous action recognition system.

Detection Algorithm of Road Damage and Obstacle Based on Joint Deep Learning for Driving Safety (주행 안전을 위한 joint deep learning 기반의 도로 노면 파손 및 장애물 탐지 알고리즘)

  • Shim, Seungbo;Jeong, Jae-Jin
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.20 no.2
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    • pp.95-111
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    • 2021
  • As the population decreases in an aging society, the average age of drivers increases. Accordingly, the elderly at high risk of being in an accident need autonomous-driving vehicles. In order to secure driving safety on the road, several technologies to respond to various obstacles are required in those vehicles. Among them, technology is required to recognize static obstacles, such as poor road conditions, as well as dynamic obstacles, such as vehicles, bicycles, and people, that may be encountered while driving. In this study, we propose a deep neural network algorithm capable of simultaneously detecting these two types of obstacle. For this algorithm, we used 1,418 road images and produced annotation data that marks seven categories of dynamic obstacles and labels images to indicate road damage. As a result of training, dynamic obstacles were detected with an average accuracy of 46.22%, and road surface damage was detected with a mean intersection over union of 74.71%. In addition, the average elapsed time required to process a single image is 89ms, and this algorithm is suitable for personal mobility vehicles that are slower than ordinary vehicles. In the future, it is expected that driving safety with personal mobility vehicles will be improved by utilizing technology that detects road obstacles.

Analytical Methods for the Analysis of Structural Connectivity in the Mouse Brain (마우스 뇌의 구조적 연결성 분석을 위한 분석 방법)

  • Im, Sang-Jin;Baek, Hyeon-Man
    • Journal of the Korean Society of Radiology
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    • v.15 no.4
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    • pp.507-518
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    • 2021
  • Magnetic resonance imaging (MRI) is a key technology that has been seeing increasing use in studying the structural and functional innerworkings of the brain. Analyzing the variability of brain connectome through tractography analysis has been used to increase our understanding of disease pathology in humans. However, there lacks standardization of analysis methods for small animals such as mice, and lacks scientific consensus in regard to accurate preprocessing strategies and atlas-based neuroinformatics for images. In addition, it is difficult to acquire high resolution images for mice due to how significantly smaller a mouse brain is compared to that of humans. In this study, we present an Allen Mouse Brain Atlas-based image data analysis pipeline for structural connectivity analysis involving structural region segmentation using mouse brain structural images and diffusion tensor images. Each analysis method enabled the analysis of mouse brain image data using reliable software that has already been verified with human and mouse image data. In addition, the pipeline presented in this study is optimized for users to efficiently process data by organizing functions necessary for mouse tractography among complex analysis processes and various functions.

A Study on Innovation Plan of Archives' Recording Service using Social Media: Focused on Gyeongnam Archives and Seoul Metropolitan Archives (소셜미디어를 이용한 기록관리기관의 기록서비스 혁신 방안 연구: 경남기록원과 서울기록원을 중심으로)

  • Kim, Ye-ji;Kim, Ik-han
    • Journal of Korean Society of Archives and Records Management
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    • v.22 no.2
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    • pp.1-25
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    • 2022
  • Today, most archives provide recording services through social media; however, their effectiveness is very low. This study aimed to analyze the causes of insufficient social media recording service, focusing on Gyeongnam Archives and Seoul Metropolitan Archives, which are permanent records management institutions and local government archives, and design ways to create synergy by mutual growth with classical recording service. Through literature research, the characteristics and mechanisms of each social medium were identified, and the institutions' current status of social media operations and internal documents were reviewed to analyze the common problems. An in-depth analysis was conducted by interviewing the person in charge of recording services at each institution. In addition, a plan that can be applied to archives was proposed by reviewing the cases of social media operations of domestic-related institutions and overseas archives. Based on this, a new recording service process was established, strategic operation plans for each social medium were proposed, and a plan to mutually grow with the existing recording service was designed.

Indonesian Halal Food Consumers' Perception, Attitude and Use of Ginseng and Red Ginseng Products (인도네시아 할랄식품 소비자의 인삼·홍삼제품에 대한 인식과 태도 및 이용 실태)

  • Park, Soojin
    • Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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    • v.7 no.11
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    • pp.1-15
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    • 2017
  • Understanding muslim consumers' needs and behaviour is an essential process for strategic product development in the Halal food market. For our study on Indonesian consumers of Halal food, we conduct a survey of 200 Muslims residing in Indonesia on awareness of ginseng (G) and red ginseng (RG) products, eating experience, like or dislike reasons, cognitive level on the efficacy of G and RG products, purchase behaviors, satisfaction and repurchase intention through a web-based questionnaire methodology. This study reveals that 58 % and 51% of the participants indicate an awareness of G and RG products. In particular, awareness amongst medium- and high-income male consumers in their 20s and 30s is relatively high. This group of participants is also more likely to consume eat G and RG products for health promotion, refreshment, and disease prevention, and positively evaluated product efficacy. They are also aware of the efficacy claims of these products with regard to enhancement of immunity, fatigue, and stamina. While Indonesian Muslim consumers express satisfaction with the health claims, packaging specifications, and design of the products, they are dissatisfied with product types, price, taste, and aroma. The results also found that participants would recommend G and RG products to acquaintances, and are willing to purchase them in the future. Therefore, the segmentation of Halal-certified G and RG products for Muslim consumers and analysis on their product needs could be advantageous for strategic product development.

A Study of Development and Application of an Inland Water Body Training Dataset Using Sentinel-1 SAR Images in Korea (Sentinel-1 SAR 영상을 활용한 국내 내륙 수체 학습 데이터셋 구축 및 알고리즘 적용 연구)

  • Eu-Ru Lee;Hyung-Sup Jung
    • Korean Journal of Remote Sensing
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    • v.39 no.6_1
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    • pp.1371-1388
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    • 2023
  • Floods are becoming more severe and frequent due to global warming-induced climate change. Water disasters are rising in Korea due to severe rainfall and wet seasons. This makes preventive climate change measures and efficient water catastrophe responses crucial, and synthetic aperture radar satellite imagery can help. This research created 1,423 water body learning datasets for individual water body regions along the Han and Nakdong waterways to reflect domestic water body properties discovered by Sentinel-1 satellite radar imagery. We created a document with exact data annotation criteria for many situations. After the dataset was processed, U-Net, a deep learning model, analyzed water body detection results. The results from applying the learned model to water body locations not involved in the learning process were studied to validate soil water body monitoring on a national scale. The analysis showed that the created water body area detected water bodies accurately (F1-Score: 0.987, Intersection over Union [IoU]: 0.955). Other domestic water body regions not used for training and evaluation showed similar accuracy (F1-Score: 0.941, IoU: 0.89). Both outcomes showed that the computer accurately spotted water bodies in most areas, however tiny streams and gloomy areas had problems. This work should improve water resource change and disaster damage surveillance. Future studies will likely include more water body attribute datasets. Such databases could help manage and monitor water bodies nationwide and shed light on misclassified regions.

Study on Applicability of Cloth Simulation Filtering Algorithm for Segmentation of Ground Points from Drone LiDAR Point Clouds in Mountainous Areas (산악지형 드론 라이다 데이터 점군 분리를 위한 CSF 알고리즘 적용에 관한 연구)

  • Seul Koo ;Eon Taek Lim ;Yong Han Jung ;Jae Wook Suk ;Seong Sam Kim
    • Korean Journal of Remote Sensing
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    • v.39 no.5_2
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    • pp.827-835
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    • 2023
  • Drone light detection and ranging (LiDAR) is a state-of-the-art surveying technology that enables close investigation of the top of the mountain slope or the inaccessible slope, and is being used for field surveys in mountainous terrain. To build topographic information using Drone LiDAR, a preprocessing process is required to effectively separate ground and non-ground points from the acquired point cloud. Therefore, in this study, the point group data of the mountain topography was acquired using an aerial LiDAR mounted on a commercial drone, and the application and accuracy of the cloth simulation filtering algorithm, one of the ground separation techniques, was verified. As a result of applying the algorithm, the separation accuracy of the ground and the non-ground was 84.3%, and the kappa coefficient was 0.71, and drone LiDAR data could be effectively used for landslide field surveys in mountainous terrain.