• Title/Summary/Keyword: Vision sensing

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A review of ground camera-based computer vision techniques for flood management

  • Sanghoon Jun;Hyewoon Jang;Seungjun Kim;Jong-Sub Lee;Donghwi Jung
    • Computers and Concrete
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    • v.33 no.4
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    • pp.425-443
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    • 2024
  • Floods are among the most common natural hazards in urban areas. To mitigate the problems caused by flooding, unstructured data such as images and videos collected from closed circuit televisions (CCTVs) or unmanned aerial vehicles (UAVs) have been examined for flood management (FM). Many computer vision (CV) techniques have been widely adopted to analyze imagery data. Although some papers have reviewed recent CV approaches that utilize UAV images or remote sensing data, less effort has been devoted to studies that have focused on CCTV data. In addition, few studies have distinguished between the main research objectives of CV techniques (e.g., flood depth and flooded area) for a comprehensive understanding of the current status and trends of CV applications for each FM research topic. Thus, this paper provides a comprehensive review of the literature that proposes CV techniques for aspects of FM using ground camera (e.g., CCTV) data. Research topics are classified into four categories: flood depth, flood detection, flooded area, and surface water velocity. These application areas are subdivided into three types: urban, river and stream, and experimental. The adopted CV techniques are summarized for each research topic and application area. The primary goal of this review is to provide guidance for researchers who plan to design a CV model for specific purposes such as flood-depth estimation. Researchers should be able to draw on this review to construct an appropriate CV model for any FM purpose.

Automatic Generation of GCP Chips from High Resolution Images using SUSAN Algorithms

  • Um Yong-Jo;Kim Moon-Gyu;Kim Taejung;Cho Seong-Ik
    • Proceedings of the KSRS Conference
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    • 2004.10a
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    • pp.220-223
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    • 2004
  • Automatic image registration is an essential element of remote sensing because remote sensing system generates enormous amount of data, which are multiple observations of the same features at different times and by different sensor. The general process of automatic image registration includes three steps: 1) The extraction of features to be used in the matching process, 2) the feature matching strategy and accurate matching process, 3) the resampling of the data based on the correspondence computed from matched feature. For step 2) and 3), we have developed an algorithms for automated registration of satellite images with RANSAC(Random Sample Consensus) in success. However, for step 1), There still remains human operation to generate GCP Chips, which is time consuming, laborious and expensive process. The main idea of this research is that we are able to automatically generate GCP chips with comer detection algorithms without GPS survey and human interventions if we have systematic corrected satellite image within adaptable positional accuracy. In this research, we use SUSAN(Smallest Univalue Segment Assimilating Nucleus) algorithm in order to detect the comer. SUSAN algorithm is known as the best robust algorithms for comer detection in the field of compute vision. However, there are so many comers in high-resolution images so that we need to reduce the comer points from SUSAN algorithms to overcome redundancy. In experiment, we automatically generate GCP chips from IKONOS images with geo level using SUSAN algorithms. Then we extract reference coordinate from IKONOS images and DEM data and filter the comer points using texture analysis. At last, we apply automatically collected GCP chips by proposed method and the GCP by operator to in-house automatic precision correction algorithms. The compared result will be presented to show the GCP quality.

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Empathy Evaluation Method Using Micro-movement (인체 미동을 이용한 공감도 평가 방법)

  • Hwang, Sung Teac;Park, SangIn;Won, Myoung Ju;Whang, Mincheol
    • Science of Emotion and Sensibility
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    • v.20 no.1
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    • pp.67-74
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    • 2017
  • The goal of this study is to present quantification method for empathy. The micro-movement technology (non-contact sensing method) was used to identify empathy level. Participants were first divided into two groups: Empathized and not empathized. Then, the upper body data of participants were collected utilizing web-cam when participants carried expression tasks. The data were analyzed and categorized into 0.5 Hz, 1 Hz, 3 Hz, 5 Hz, 15 Hz. The average movement, variation, and synchronization of the movement were then compared. The results showed a low average movement and variation in a group who empathized. Also, the participants, who empathized, synchronized their movement during the task. This indicates that the people concentrates with each other when empathy has been established and show different levels of movement. These findings suggest the possibility of empathy quantification using non-contact sensing method.

Wavelet Packet Image Coder Using Coefficients Partitioning For Remote Sensing Images (위성 영상을 위한 계수분할 웨이블릿 패킷 영상 부호화 알고리즘에 관한 연구)

  • 한수영;조성윤
    • Korean Journal of Remote Sensing
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    • v.18 no.6
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    • pp.359-367
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    • 2002
  • In this paper, a new embedded wavelet packet image coder algorithm is proposed for an effective image coder using correlation between partitioned coefficients. This new algorithm presents parent-child relationship for reducing image reconstruction error using relations between individual frequency sub-bands. By parent-child relationship, every coefficient is partitioned and encoded for the zerotree data structure. It is shown that the proposed wavelet packet image coder algorithm achieves low bit rates and rate-distortion. It also demonstrates higher PSNR under the same bit rate and an improvement in image compression time. The perfect rate control is compared with the conventional method. These results show that the encoding and decoding processes of the proposed coder are simpler and more accurate than the conventional ones for texture images that include many mid and high-frequency elements such as aerial and satellite photograph images. The experimental results imply the possibility that the proposed method can be applied to real-time vision system, on-line image processing and image fusion which require smaller file size and better resolution.

Framework of a Cooperative Control Software for Heterogeneous Multiple Network Based Humanoid (이종 다수의 네트워크 기반 휴머노이드를 위한 협조제어 소프트웨어 프레임워크)

  • Lim, Heon-Young;Kang, Yeon-Sik;Lee, Joong-Jae;Kim, Jong-Won;You, Bum-Jae
    • The Journal of Korea Robotics Society
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    • v.3 no.3
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    • pp.226-236
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    • 2008
  • In this paper, control software architecture is designed to enable a heterogeneous multiple humanoid robot demonstration executing tasks cooperating with each other. In the heterogeneous humanoid robot team, one large humanoid robot and two small humanoid robots are included. For the efficient and reliable information sharing between many software components for humanoid control, sensing and planning, CORBA based software framework is applied. The humanoid tasks are given in terms of finite state diagram based human-robot interface, which is interpreted into the XML based languages defining the details of the humanoid mission. A state transition is triggered based on the event which is described in terms of conditions on the sensor measurements such as robot locations and the external vision system. In the demonstration of the heterogeneous humanoid team, the task of multiple humanoid cleaning the table is given to the humanoid robots and successfully executed based on the given state diagram.

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A study on the characteristic analysis and correction of non-linear bias error of an infrared range finder sensor for a mobile robot (이동로봇용 적외선 레인지 파인더센서의 특성분석 및 비선형 편향 오차 보정에 관한 연구)

  • 하윤수;김헌희
    • Journal of Advanced Marine Engineering and Technology
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    • v.27 no.5
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    • pp.641-647
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    • 2003
  • The use of infrared range-finder sensor as the environment recognition system for mobile robot have the advantage of low sensing cost compared with the use of other vision sensor such as laser finder CCD camera. However, it is not easy to find the previous works on the use of infrared range-finder sensor for a mobile robot because of the non-linear characteristic of that. This paper describes the error due to non-linearity of a sensor and the correction of it using neural network. The neural network consists of multi-layer perception and Levenberg-Marquardt algorithm is applied to learning it. The effectiveness of the proposed algorithm is verified from experiment.

Insect GPCRs and TRP Channels: Putative Targets for Insect Repellents

  • Kim, Sang Hoon
    • Interdisciplinary Bio Central
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    • v.5 no.3
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    • pp.6.1-6.7
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    • 2013
  • Many insects such as mosquitoes cause life-threatening diseases such as malaria, yellow fever and West Nile virus. Malaria alone infects 500 million people annually and causes 1-3 million death per year. Volatile insect repellents, which are detected through the sense of smell, have long been used to protect humans against insect pests. Antifeed-ants are non-volatile aversive compounds that are detected through the sense of taste and prevent insects from feeding on plants. The molecular targets and signaling path-ways required for sensing insect repellents and antifeedants are poorly understood. Transient Receptor Potential (TRP) Ca2+-permeable cation channels exist in organisms ranging from C. elegans to D. melanogaster and Homo sapiens. Drosophila has 13 family members, which mainly function in sensory physiology such as vision, thermotaxis and chemotaxis. G protein-coupled receptors (GPCRs) initiate olfactory signaling cascades in mammals and in nematodes C.elegans. However, the mechanisms of G protein signaling cascades in insect chemosensation are controversial. In this review, I will discuss the putative roles of G protein-coupled receptors (GPCRs) and Transient Receptor Potential (TRP) channels as targets for insect repellents.

Automatic Registration of Two Parts using Robot with Multiple 3D Sensor Systems

  • Ha, Jong-Eun
    • Journal of Electrical Engineering and Technology
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    • v.10 no.4
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    • pp.1830-1835
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    • 2015
  • In this paper, we propose an algorithm for the automatic registration of two rigid parts using multiple 3D sensor systems on a robot. Four sets of structured laser stripe system consisted of a camera and a visible laser stripe is used for the acquisition of 3D information. Detailed procedures including extrinsic calibration among four 3D sensor systems and hand/eye calibration of 3D sensing system on robot arm are presented. We find a best pose using search-based pose estimation algorithm where cost function is proposed by reflecting geometric constraints between sensor systems and target objects. A pose with minimum gap and height difference is found by greedy search. Experimental result using demo system shows the robustness and feasibility of the proposed algorithm.

Onboard Active Vision Based Hovering Control for Quadcopter in Indoor Environments (실내 환경에서의 능동카메라 기반 쿼더콥터의 호버링 제어)

  • Jin, Tae-Seok
    • Journal of the Korean Society of Industry Convergence
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    • v.20 no.1
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    • pp.19-26
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    • 2017
  • In this paper, we describe the design and performance of UAV system toward compact and fully autonomous quadrotors, where they can complete logistics application, rescue work, inspection tour and remote sensing without external assistance systems like ground station computers, high-performance wireless communication devices or motion capture system. we propose high-speed hovering flyght height control method based on state feedback control with image information from active camera and multirate observer because we can get image of the information only every 30ms. Finally, we show the advantages of proposed method by simulations and experiments.

Refinement of DEM boundaries using Point Distribution Criteria in Scattered Data Interpolation

  • KIM Seung-Bum
    • Proceedings of the KSRS Conference
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    • 2004.10a
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    • pp.103-106
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    • 2004
  • Extrapolation off the boundaries of scattered data is an intrinsic feature of interpolation. However, extrapolation causes serious problems in stereo-vision and mapping, which has not been investigated carefully. In this paper, we present novel schemes to eliminate the extrapolation effects for the generation of a digital elevation model (DEM). As a first step, we devise point distribution criteria, namely COG (Center of Gravity) and ECI (Empty Center Index), and apply rigorous and robust elimination based on the criteria. Compared with other methods, the proposed schemes are computationally fast and applicable to a wide range of interpolation techniques.

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