• Title/Summary/Keyword: Location verification

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A Study on Airborne LiDAR Calibration and Operation Techniques for Bathymetric Survey

  • Shin, Moon Seung;Yang, In Tae;Lee, Dong Ha
    • Journal of Korean Society for Geospatial Information Science
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    • v.24 no.2
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    • pp.113-120
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    • 2016
  • The necessity of maritime sector for continuous management, accurate and update location information such as seabed shape and location, research on airborne LiDAR bathymetry surveying techniques are accelerating. Airborne LiDAR systems consist of a scanner and GPS/INS. The location accuracy of 3D point data obtained by a LiDAR system is determined by external orientation parameters. However, there are problems in the synchronization between sensors should be performed due to a variety of sensor combinations and arrangement. To solve this issue, system calibration should be conducted. Therefore, this study evaluates the system verification methods, processes, and operation techniques.

On the Assembly Block Storage Location Assignment Problem (조립블록 저장위치 할당문제에 대한 재고찰)

  • Park, Chang-Kyu;Seo, Jun-Yong
    • IE interfaces
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    • v.22 no.2
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    • pp.116-125
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    • 2009
  • We revisit the assembly block storage location assignment problem (ABSLAP) at a shipyard, in order to compensate for the deficiency in performance verification of the heuristic ABSLAP algorithm developed by the previous study. In this paper, we formulate a mathematical programming model of the ABSLAP, refine elaborately the heuristic ABSLAP algorithm, and show the performance of the developed mathematical programming model and the revised heuristic ABSLAP algorithm. In addition, we explain simulation experiments conducted using the revised heuristic ABSLAP algorithm to investigate the influences of block stockyard layouts and production schedule instability on the block stockyard operations.

Study on Location-Specific Live Load Model for Verification of Bridge Reliability Based on Probabilistic Approach (교량의 신뢰성 검증을 위한 지역적 활하중 확률모형 구축)

  • Eom, Jun Sik
    • Journal of Applied Reliability
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    • v.16 no.2
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    • pp.90-97
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    • 2016
  • Purpose: Majority of bridges and roads in Gangwon Province have been carrying loads associated with heavy materials such as rocks, mining products, and cement. This location-specific live loads have contributed to the present situation of overloading, compared to other provinces in Korea. However, the bridges in Gangwon province are designed by national bridge design specification, without considering the location-specific live load characteristics. Therefore, this study focuses on the real traffic data accumulated on regional weighing station to verify the live load characteristics, including actual live load gross vehicle weight, axle weight axle spacings, and number of trucks. Methods: In order to take into account the location specific live load, a governmental weigh station (38th national highway Miro) have been selected and the passing truck data are processed. Based on the truck survey, trucks are categorized into 3 different shapes, and each shape has been idealized into normal distribution. Then, the resulting survey data are processed to predict the target maximum live load values, including the axle loads and gross vehicle weights in 75 years service life span. Results: The results are compared to the nationally used DB-24 live loads, and the results show that nationally recognized DB-24 live load does not sufficiently represent real traffic in mountaineous region in Gangwon province. Conclusion: The comparison results in the recommendation of location-specific live load that should be taken into account for bridge design and evaluation.

Estimation of the Sensor Location and the Step for Personal Navigation System (개인 항법 시스템을 위한 센서 위치와 보폭 추정 알고리즘)

  • Kim, Tae-Un;Lee, Ho-Won;Chwa, Dong-Kyoung;Hong, Suk-Kyo
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.59 no.11
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    • pp.2058-2065
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    • 2010
  • This paper presents the sensor location and step estimation algorithm for personal navigation system (PNS). PNS has the disadvantage in that the position of the sensor must be fixed on a human body. Three-axis acceleration sensor is used to solve the disadvantage and to consider the real situation. We simplify the measurement data by using the band pass filter, witch It has the advantage in the detection of characteristic point. Through the detected characteristic points, it is possible to setup the parameter for the pattern detection. Depending on the sensor location, the parameters have the different type of noise covariance. Particularly, when the position of the sensor is changed, the impulse noise shows up. Considering the noise, we apply the recursive least square algorithm using the variable forgetting factors, which can classify the sensor location based on the estimated parameters. We performed the experiment for the verification of the proposed algorithm in the various environments. Through the experimental results, the effectiveness of the proposed method is verified.

An Anonymous Authentication Scheme for Health Information Push Service Based on Indoor Location in Hospital (병원 실내 위치기반 의료정보 푸쉬 서비스를 위한 익명 인증 스킴)

  • Ahn, Hae-Soon;Yoon, Eun-Jun;Nam, In-Gil
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.37 no.5C
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    • pp.410-419
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    • 2012
  • This paper proposes a secure and efficient anonymous authentication scheme for health information push service based on indoor location in hospital. The proposed scheme has the following benefits: (1)It is just based on a secure one-way hash function for avoiding complex computations for both health care operations users and health care centers. (2)It does not require sensitive verification table which may cause health care centers to become an attractive target for numerous attacks(e.g., insertion attacks and stolen-verifier attacks), (3)It provides higher security level (e.g., secure mutual authentication and key establishment, confidential communication, user's privacy, simple key management, and session key independence). As result, the proposed scheme is very suitable for various location-based medical information service environments using lightweight-device(e.g., smartphone) because of very low computation overload on the part of both health care operations users and health care centers.

Development of Web-based Power Plant Simulator System (원격 훈련용 발전 시뮬레이터 개발)

  • Byun, Seung-Hyun;Kang, Hae-su;Woo, Joo-Hee;Lee, Jee-Hoon;Kim, Duck-Ho
    • KEPCO Journal on Electric Power and Energy
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    • v.7 no.2
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    • pp.277-283
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    • 2021
  • Power plant simulators have been used for operator training, control verification and engineering verification. In general, simulators can be used in the place where they are installed by only single user group at a time. Considering high cost of simulator development, a lot of available scenarios, the diversity of user level and accessibility based on users' work location, development of simulator system that can be used by multiple user groups regardless of location is required in order to enhance utilization of simulators. In this paper, the simulator system that can be used by multiple user group simultaneously without location limitation is proposed. The simulator system is composed of simulator servers, database servers, HMI servers, a web server, web clients. Simulator server consists of control model, process model that are developed for Circulating Fluidized Bed power plant located overseas. A web server manages user accounts, operation procedures, multiple server access between web client group and simulator server group. In other words, a web server makes a user group select a simulator server at a time. The developed simulator system is integrated after implementing process model, control model, HMI, and web server. Web client systems are installed on local site where power plant is located, while simulator servers, HMI servers, database servers, and a web server are located in KEPCO RI. The developed simulator system is verified by steady-state test, malfunction test and so on via remote access.

Performance Analysis on an Object Location Estimation Algorithm Using a Single Receiver (단일 수신기를 이용한 객체 위치추정 알고리즘 성능평가)

  • Myagmar, Enkhzaya;Kwon, Soonryang;Lee, Dong Myung
    • Journal of KIISE
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    • v.42 no.2
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    • pp.264-271
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    • 2015
  • The general way to use a triangulation method is based on PTMP communication between an object and wireless modules in an environment, which is established by more than three wireless modules, to recognize the location of an object. Thus, this method has a problem that the PTMP-based system can only be applied in an environment where the wireless infra is already established. In order to solve this problem, the PTP communication schemes have been proposed but they are insufficient to generalize because they lack specific verification. In this paper, problems of an existed location estimation algorithm based on PTP communication are analyzed, and we propose a location estimation algorithm of a fixed object that satisfyies the condition of a single receiver being substituted to multiple receivers. A location estimation system we designed and implemented using CSS wireless communication modules to evaluate the proposed algorithm. We verify, by experimental results, that the optimum moving interval for the location estimation is 3m in indoor environment of $10m{\times}16m{\times}1m$.

Location Error of the Dens in a Two-Dimensional Set-up Verification During Head and Neck Radiotherapy (뇌.두경부 방사선치료 시 전자조사문영상장치를 이용한 세트업 오차 확인에서 제2경추 치상돌기 위치의 임상적 의의)

  • Kim, Dong-Hyun;Kim, Won-Taek;Ki, Yong-Gan;Nam, Ji-Ho;Lee, Mi-Ran;Jeon, Ho-Sang;Park, Dal;Kim, Dong-Won
    • Radiation Oncology Journal
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    • v.29 no.2
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    • pp.107-114
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    • 2011
  • Purpose: To assess the degree and clinical impact of location error of the dens on the X-axis during radiotherapy to brain and head and neck tumors. Materials and Methods: Twenty-one patients with brain tumors or head and neck tumors who received three-dimensional conformal radiation therapy or intensity-modulated radiation therapy from January 2009 to June 2010 were included in this study. In comparison two-dimensional verification portal images with initial simulation images, location error of the nasal septum and the dens on the X-axis was measured. The effect of set-up errors of the dens was simulated in the planning system and analyzed with physical dose parameters. Results: A total of 402 portal images were reviewed. The mean location error at the nasal septum was 0.16 mm and at the dens was 0.33 mm (absolute value). Location errors of more than 3 mm were recorded in 43 cases (10.7%) at the nasal septum, compared to 133 cases (33.1%) at the dens. There was no case with a location error more than 5 mm at the nasal septum, compared to 11 cases (2.7%) at the dens. In a dosimetric simulation, a location error more than 5 mm at the dens could induce a reduction in the clinical target volume 1 coverage (V95: 100%${\rightarrow}$87.2%) and overdosing to a critical normal organ (Spinal cord V45: <0.1%${\rightarrow}$12.6%). Conclusion: In both brain and head and neck radiotherapy, a relatively larger set-up error was detected at the dens than the nasal septum when using an electronic portal imaging device. Consideration of the location error of the dens is necessary at the time of the precise radiation beam delivery in two-dimensional verification systems.

Standard Model for Mobile Forensic Image Development

  • Sojung, Oh;Eunjin, Kim;Eunji, Lee;Yeongseong, Kim;Gibum, Kim
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.17 no.2
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    • pp.626-643
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    • 2023
  • As mobile forensics has emerged as an essential technique, the demand for technology development, education and training is increasing, wherein images are used. Academic societies in South Korea and national institutions in the US and the UK are leading the Mobile Forensic Image development. However, compared with disks, images developed in a mobile environment are few cases and have less active research, causing a waste of time, money, and manpower. Mobile Forensic Images are also difficult to trust owing to insufficient verification processes. Additionally, in South Korea, there are legal issues involving the Telecommunications Business Act and the Act on the Protection and Use of Location Information. Therefore, in this study, we requested a review of a standard model for the development of Mobile Forensic Image from experts and designed an 11-step development model. The steps of the model are as follows: a. setting of design directions, b. scenario design, c. selection of analysis techniques, d. review of legal issues, e. creation of virtual information, f. configuring system settings, g. performing imaging as per scenarios, h. Developing a checklist, i. internal verification, j. external verification, and k. confirmation of validity. Finally, we identified the differences between the mobile and disk environments and discussed the institutional efforts of South Korea. This study will also provide a guideline for the development of professional quality verification and proficiency tests as well as technology and talent-nurturing tools. We propose a method that can be used as a guide to secure pan-national trust in forensic examiners and tools. We expect this study to strengthen the mobile forensics capabilities of forensic examiners and researchers. This research will be used for the verification and evaluation of individuals and institutions, contributing to national security, eventually.

Clinical Risk Evaluation Using Dose Verification Program of Brachytherapy for Cervical Cancer (자궁경부암 근접치료 시 선량 검증 프로그램을 통한 임상적 위험성 평가)

  • Dong‑Jin, Kang;Young‑Joo, Shin;Jin-Kyu, Kang;Jae‑Yong, Jung;Woo-jin, Lee;Tae-Seong, Baek;Boram, Lee
    • Journal of radiological science and technology
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    • v.45 no.6
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    • pp.553-560
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    • 2022
  • The purpose of this study is to evaluate the clinical risk according to the applicator heterogeneity, mislocation, and tissue heterogeneity correction through a dose verification program during brachytherapy of cervical cancer. We performed image processing with MATLAB on images acquired with CT simulator. The source was modeled and stochiometric calibration and Monte-Carlo algorithm were applied based on dwell time and location to calculate the dose, and the secondary cancer risk was evaluated in the dose verification program. The result calculated by correcting for applicator and tissue heterogeneity showed a maximum dose of about 25% higher. In the bladder, the difference in excess absolute risk according to the heterogeneity correction was not significant. In the rectum, the difference in excess absolute risk was lower than that calculated by correcting applicator and tissue heterogeneity compared to the water-based calculation. In the femur, the water-based calculation result was the lowest, and the result calculated by correcting the applicator and tissue heterogeneity was 10% higher. A maximum of 14% dose difference occurred when the applicator mislocation was 20 mm in the Z-axis. In a future study, it is expected that a system that can independently verify the treatment plan can be developed by automating the interface between the treatment planning system and the dose verification program.