• Title/Summary/Keyword: location tracing

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Development of a Fall Detection System Using Fish-eye Lens Camera (어안 렌즈 카메라 영상을 이용한 기절동작 인식)

  • So, In-Mi;Han, Dae-Kyung;Kang, Sun-Kyung;Kim, Young-Un;Jong, Sung-tae
    • Journal of the Korea Society of Computer and Information
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    • v.13 no.4
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    • pp.97-103
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    • 2008
  • This study is to present a fainting motion recognizing method by using fish-eye lens images to sense emergency situations. The camera with fish-eye lens located at the center of the ceiling of the living room sends images, and then the foreground pixels are extracted by means of the adaptive background modeling method based on the Gaussian complex model, which is followed by tracing of outer points in the foreground pixel area and the elliptical mapping. During the elliptical tracing, the fish-eye lens images are converted to fluoroscope images. the size and location changes, and moving speed information are extracted to judge whether the movement, pause, and motion are similar to fainting motion. The results show that compared to using fish-eye lens image, extraction of the size and location changes. and moving speed by means of the conversed fluoroscope images has good recognition rates.

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Active Focusing Technique for Extracting Depth Information (액티브 포커싱을 이용한 3차원 물체의 깊이 계측)

  • 이용수;박종훈;최종수
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.29B no.2
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    • pp.40-49
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    • 1992
  • In this paper,a new approach-using the linear movement of the lens location in a camera and focal distance in each location for the measurement of the depth of the 3-D object from several 2-D images-is proposed. The sharply focused edges are extracted from the images obtained by moving the lens of the camera, that is, the distance between the lens and the image plane, in the range allowed by the camera lens system. Then the depthin formation of the edges are obtained by the lens location. In our method, the accurate and complicated control system of the camera and a special algorithm for tracing the accurate focus point are not necessary, and the method has some advantage that the depth of all objects in a scene are measured by only the linear movement of the lens location of the camera. The accuracy of the extracted depth information is approximately 5% of object distances between 1 and 2m. We can see the possibility of application of the method in the depth measurement of the 3-D objects.

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A Trajectory Substitution Privacy Protection Scheme in location-based services

  • Song, Cheng;Zhang, Yadong;Gu, Xinan;Wang, Lei;Liu, Zhizhong
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.13 no.9
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    • pp.4771-4787
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    • 2019
  • Aimed at the disclosure risk of mobile terminal user's location privacy in location-based services, a location-privacy protection scheme based on similar trajectory substitution is proposed. On the basis of the anonymized identities of users and candidates who request LBS, this scheme adopts trajectory similarity function to select the candidate whose trajectory is the most similar to user's at certain time intervals, then the selected candidate substitutes user to send LBS request, so as to protect user's privacy like identity, query and trajectory. Security analyses prove that this scheme is able to guarantee such security features as anonymity, non-forgeability, resistance to continuous query tracing attack and wiretapping attack. And the results of simulation experiment demonstrate that this scheme remarkably improve the optimal candidate' trajectory similarity and selection efficiency.

RFID Authentication Protocol with Strong Resistance against Traceability and Denial of Service attack (위치 추적과 서비스 거부 공격에 강한 RFID 인증 프로토콜)

  • Kang, Jeon-Il;Nyang, Dae-Hun
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.15 no.4
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    • pp.71-82
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    • 2005
  • Though there are many authentication protocols for RFID system, only a few protocols support location privacy. Because of tag's hardware limitation, these protocols suffer from many security threats, especially from DoS (Denial of Service) attack. In this paper, we explain location privacy problem and show vulnerabilities of RFID authentication protocols. And then, we suggest an authentication protocol that is strong against location tracing, spoofing attack and DoS attack

A Precise Location Tracking System with Smart Context-Awareness Based-on Doppler Radar Sensors (스마트한 상황인지를 적용한 도플러 레이더 센서 기반의 정밀 위치추정 시스템)

  • Moon, Seung-Jin;Kim, Hong-Kyu
    • Journal of Institute of Control, Robotics and Systems
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    • v.16 no.12
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    • pp.1159-1166
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    • 2010
  • Today, detecting the location of moving object has been traced as various methods in our world. In this paper, we preset the system to improve the estimation accuracy utilizing detail localization using radar sensor based on WSN and situational awareness for a calibration (context aware) database, Rail concept. A variety of existing location tracking method has a problem with receiving of data and accuracy as tracking methodology, and since these located data are the only data to be collected for location tracing, the context aware or monitering as the surrounding environment is limited. So, in this paper, we enhanced the distance aware accuracy using radar sensor utilizing the Doppler effect among the distance measuring method, estimated the location using the Triangulation algorithm. Also, since we composed the environment data(temperature, illuminancem, humidity, noise) to entry of the database, it can be utilized in location-based service according to the later action information inference and positive context decision. In order to verify the validity of the suggested method, we give a few random situation and built test bed of designed node, and over the various test we proved the utilizing the context information through route tracking of moving and data processing.

Analysis of Sun Tracking Error Caused by the Heliostat Driving Axis Geometrical Error Utilizing the Solar Ray Tracing Technique (태양광선 제적추적기법을 이용한 Heliostat 구동축 기구오차에서 기인하는 태양추적오차의 분석)

  • Park, Young-Chil
    • Journal of the Korean Solar Energy Society
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    • v.29 no.2
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    • pp.39-46
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    • 2009
  • Heliostat, as a mirror system tracking the sun's movement, is the most important subsystem determining the efficiency of solar thermal power plant. Thus the accurate sun tracking performance under the various hazardous operating condition, is required. This study presents a methodology of development of the solar ray tracing technique and the application of it in the analysis of sun tracking error due to the heliostat geometrical errors. The geometrical errors considered here are the azimuth axis tilting error and the elevation axis tilting error. We first analyze the geometry of solar ray reflected from the heliostat. Then the point on the receiver, where the solar ray reflected from the heliostat is landed, is computed and compared with the original intended point, which represents the sun tracking error. The result obtained shows that the effect of geometrical error on the sun tracking performance is varying with time(season) and the heliostat location. It also shows that the heliostat located near the solar tower has larger sun tracking error than that of the heliostat located farther.

RFID-based Shortest Time Algorithm Line Tracer (RFID 기반 최단시간 알고리즘 라인트레이서)

  • Cheol-Min, Kim;Hee-Young, Cho;Tae-Sung, Yun;Ho-Jun, Shin;Hyoung-Keun, Park
    • The Journal of the Korea institute of electronic communication sciences
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    • v.17 no.6
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    • pp.1221-1228
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    • 2022
  • With the development of modern technology, the use of unmanned automation equipment that can replace humans in logistics and industrial sites is increasing. The technology of one such automation facility, the Unmanned Carrier (AGV), includes Line Tracing, which allows you to recognize a line through infrared sensors and drive a predetermined route. In this paper, the shortest time algorithm using Arduino is configured in the line tracing technology to enable efficient driving. It is also designed to collect location and time information using RFID tags.

Reordering Scheme of Location Identifiers for Indexing RFID Tags (RFID 태그의 색인을 위한 위치 식별자 재순서 기법)

  • Ahn, Sung-Woo;Hong, Bong-Hee
    • Journal of KIISE:Databases
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    • v.36 no.3
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    • pp.198-214
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    • 2009
  • Trajectories of RFID tags can be modeled as a line, denoted by tag interval, captured by an RFID reader and indexed in a three-dimensional domain, with the axes being the tag identifier (TID), the location identifier (LID), and the time (TIME). Distribution of tag intervals in the domain space is an important factor for efficient processing of a query for tracing tags and is changed according to arranging coordinates of each domain. Particularly, the arrangement of LIDs in the domain has an effect on the performance of queries retrieving the traces of tags as times goes by because it provides the location information of tags. Therefore, it is necessary to determine the optimal ordering of LIDs in order to perform queries efficiently for retrieving tag intervals from the index. To do this, we propose LID proximity for reordering previously assigned LIDs to new LIDs and define the LID proximity function for storing tag intervals accessed together closely in index nodes when a query is processed. To determine the sequence of LIDs in the domain, we also propose a reordering scheme of LIDs based on LID proximity. Our experiments show that the proposed reordering scheme considerably improves the performance of Queries for tracing tag locations comparing with the previous method of assigning LIDs.

Location Based Routing Service In Distributed Web Environment

  • Kim, Do-Hyun;Jang, Byung-Tae
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.340-342
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    • 2003
  • Location based services based on positions of moving objects are expanding the business area gradually. The location is included all estimate position of the future as well as the position of the present and the past. Location based routing service is active business application in which the position information of moving objects is applied efficiently. This service includes the trajectory of past positions, the real-time tracing of present position of special moving objects, and the shortest and optimized paths combined with map information. In this paper, we describes the location based routing services is extend in distributed web GIS environment. Web GIS service systems provide the various GIS services of analyzing and displaying the spatial data with friendly user - interface. That is, we propose the efficient architecture and technologies for servicing the location based routing services in distributed web GIS environment. The position of moving objects is acquired by GPS (Global Positioning System) and converted the coordinate of real world by map matching with geometric information. We suppose the swapping method between main memory and storages to access the quite a number of moving objects. And, the result of location based routing services is wrapped the web-styled data format. We design the schema based on the GML. We design these services as components were developed in object-oriented computing environment, and provide the interoperability, language-independent, easy developing environment as well as re - usability.

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The Design and Implementation of a Vehicle Location Tracing System using RM Multi-Session Processing (RM 다중세션 처리를 이용한 차량 추적 시스템의 설계 및 구현)

  • Lee, Yong Kwon;Jang, Chung Ryong;Lee, Dae Sik
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.10 no.2
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    • pp.61-73
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    • 2014
  • An automatic vehicle location tracing system is to build GIS server and on transmission for providing service in various ways by collecting a GPS location information from each vehicle. It is to save GPS data from OBU built-in on the vehicle and transmit the GPS data using the RSU on the roadside and WAVE communication technology. The collected data from the RSU is transmitted to the GIS server and stored in DB(database) and based on the GPS data that was collected from the each vehicle the system is to provide user service to suit the applications so it is to provide various services between RSU and OBU. In this paper, by implementing a multi-session process between the RM and the RMA a variety of services between RSU and OBU are provided. In addition, the system is designed and implemented using GPS to provide a variety of services, for the services provided from each RMA by configuring them as an independent session so it enables a variety of services implemented from one of RSU. With the result of the comparative analysis on the multi-session processing and single-session processing it shows that the differenes of them are minor in repect of the data loss rate and the data transfer rate but various services can be provided.