• Title/Summary/Keyword: Localization device

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Implementation for precisely localizing and parking of Bimodal Tram (바이모달 트램의 위치 인식 방법 및 정밀 정차 구현)

  • Seo, Ki-Won;Park, Ju-Yeon;Lee, Sang-Nam;Ryu, Hee-Moon;Byun, Yeun-Sub
    • Proceedings of the KSR Conference
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    • 2009.05a
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    • pp.452-456
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    • 2009
  • This paper presents a method for precisely localizing and parking of bimodal trams. In order to gam an automatically driving system for bimodal trams, precise up-to-date localization, velocity recognition, distance to next station and precise parking location estimation functions are required. This paper proposes a system consisting of control device, steering device, sensor input equipment, driving system, tachometer, vehicle-side sensors, magnetic markers and magnetic sensors. The tram recognizes the precise location via magnetic markers containing information. Parking position and precise distance calculation is embodied by a tachometer. The vehicle-side sensors are used to assure safe station approaching and parking magnetic markers provide improvement of precision while tram parking. This paper provides a system realizing localization and precise parking and afterwards the automatic drive test results are reported and analyzed.

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Factor Graph-based Multipath-assisted Indoor Passive Localization with Inaccurate Receiver

  • Hao, Ganlin;Wu, Nan;Xiong, Yifeng;Wang, Hua;Kuang, Jingming
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.10 no.2
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    • pp.703-722
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    • 2016
  • Passive wireless devices have increasing civilian and military applications, especially in the scenario with wearable devices and Internet of Things. In this paper, we study indoor localization of a target equipped with radio-frequency identification (RFID) device in ultra-wideband (UWB) wireless networks. With known room layout, deterministic multipath components, including the line-of-sight (LOS) signal and the reflected signals via multipath propagation, are employed to locate the target with one transmitter and a single inaccurate receiver. A factor graph corresponding to the joint posterior position distribution of target and receiver is constructed. However, due to the mixed distribution in the factor node of likelihood function, the expressions of messages are intractable by directly applying belief propagation on factor graph. To this end, we approximate the messages by Gaussian distribution via minimizing the Kullback-Leibler divergence (KLD) between them. Accordingly, a parametric message passing algorithm for indoor passive localization is derived, in which only the means and variances of Gaussian distributions have to be updated. Performance of the proposed algorithm and the impact of critical parameters are evaluated by Monte Carlo simulations, which demonstrate the superior performance in localization accuracy and the robustness to the statistics of multipath channels.

Localization using Neural Networks and Push-Pull Estimation based on RSS from AP to Mobile Device (통신기지국과 모바일장치간의 수신신호강도를 기반으로 하는 신경망과 푸쉬-풀 평가를 이용한 위치추정)

  • Cho, Seong-Jin;Lee, Sung-Young
    • The KIPS Transactions:PartD
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    • v.19D no.3
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    • pp.237-246
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    • 2012
  • Although the development of Global Positioning System (GPS) are more and more mature, its accuracy is just acceptable for outdoor positioning, not positioning for the indoor of building and the underpass. For the positioning application area for the indoor of building and the underpass, GPS even cannot achieve that accuracy because of the construction materials while the requirement for accurate positioning in the indoor of building and the underpass, because a space, a person is necessary, may be very small space with several square meters in the indoor of building and the underpass. The Received Signal Strength (RSS) based localization is becoming a good choice especially for the indoor of building and the underpass scenarios where the WiFi signals of IEEE 802.11, Wireless LAN, are available in almost every indoor of building and the underpass. The fundamental requirement of such localization system is to estimate location from Access Point (AP) to mobile device using RSS at a specific location. The Multi-path fading effects in this process make RSS to fluctuate unpredictably, causing uncertainty in localization. To deal with this problem, the combination for the method of Neural Networks and Push-Pull Estimation is applied so that the carried along the devices can learn and make the decision of position using mobile device where it is in the indoor of building and the underpass.

Implementation and Performance Evaluation of a Precision Localizing Device for Hyperloop Pods Driving at Ulta-High Speeds (초고속주행 하이퍼루프 포드의 정밀 위치측정 장치 구현 및 성능평가)

  • Ok, Min-Hwan;Choi, Su-Yong;Choe, Jae-Heon;Lee, Kwan-Sup
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.13 no.5
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    • pp.443-451
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    • 2020
  • A futuristic locomotion system called Hyperloop is projected for driving at ulta-high speed, levitated in the tube. In hyperloop localization of pods on the linear synchronous motor is essential for pod driving. precision localization is required for acceleration and deceleration of pods driving at speed above 1,000km/h, and also required for adjusting the pod speed driving at this very-high speed to maintain inter-vehicle distance. In this work, a new scale of localization is challenged by modified laser surface velocimeter. In acceleration the speed of a virtual pod is calculated along its displacement measured by laser reflection. Under the requirement of precise localization of the pod driving at ultra-high speed, a displacement measurement device, which detects the difference in reflections from tiles passing by the pod, is developed and evaluated through performance test. Tests of pod speeds below 500km/h have showed exact localization results of the precision in centimeters, and tests of pod speeds above 500km/h have showed localization with very low error rates under 0.1%. For the measurement above 500km/h, future works would pursue the error rate converges to zero.

Stereotactic Radiosurgery for Recurrent Glioblastoma Multiforme using Yeungnam Localization Device - Technical note and Clinical trial - (뇌정위적 방사선 절제술에 필요한 위치선정용기구 제작과 치험 2예)

  • Shin, Sei-One;Kim, Sung-Kyu;Kim, Myung-Se;Kim, Oh-Lyong;Cho, Soo-Ho
    • Radiation Oncology Journal
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    • v.10 no.1
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    • pp.101-105
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    • 1992
  • Authors performed a stereotactic radiosurgery with multiple noncoplanar convergent photon beams of linear accelerator (NELAC-1018 18 MeV, NEC) using a specially designed Yeungnam localization device for two patients with recurrent glioblastoma multiforme. One patient had 2 cm sized and the other 4 cm sized mass on the CT images. After single session of treatment with 15 and 20 Gy, headache was improved in a few days after radiosurgery with no remarkable untoward reactions. Our experience with these two patients were encouraging and we found that our localization device, which is easily adjustable and inexpensive, could be a valuable tool for stereotactic radiosurgery particularly in the treatment of recurrent brain tumor.

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An Improved DV-Hop Algorithm for Scalable Wireless Sensor Network (Scalable 무선 센서 네트워크를 위한 향상된 DV-Hop 알고리즘)

  • Lee, Byeong-Tae;Kim, Sun-Woo
    • Proceedings of the IEEK Conference
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    • 2008.06a
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    • pp.277-278
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    • 2008
  • Localization system is an important problem for Wireless Sensor Networks(WSN). Since the sensor nodes are limited, the range-based that uses the special device for localization is unsuitable in WSN. DV-Hop is one of the range-free localization algorithm using hop-distance and number of hop count. But Its disadvantage is that it spend large communication cost in scalable sensor nodes. We propose a simple algorithm to reduce the communication cost, using the smallest number of hop count.

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MRI-guided Wire Localization Open Biopsy is Safe and Effective for Suspicious Cancer on Breast MRI

  • Wang, Hai-Yi;Zhao, Yu-Nian;Wu, Jian-Zhong;Wang, Zheng;Tang, Jing-Hai
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.5
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    • pp.1715-1718
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    • 2015
  • Background: Magnetic resonance imaging of breast, reported to be a high sensitivity of 94% to 100%, is the most sensitive method for detection of breast cancer. The purpose of this study was to investigate our clinical experience in MRI-guided breast lesion wire localization in Chinese women. Materials and Methods: A total of 44 patients with 46 lesions undergoing MRI-guided breast lesion localization were prospectively entered into this study between November 2013 and September 2014. Samples were collected using a 1.5-T magnet with a special MR biopsy positioning frame device. We evaluated clinical lesion characteristics on pre-biopsy MRI, pathologic results, and dynamic curve type baseline analysis. Results: Of the total of 46 wire localization excision biopsied lesions carried out in 44 female patients, pathology revealed fourteen malignancies (14/46, 30.4%) and thirty-two benign lesions (32/46, 69.6%). All lesions were successfully localized followed by excision biopsy and assessed for morphologic features highly suggestive of malignancy according to the American College of Radiology Breast Imaging Reporting and Data System (BI-RADS) category of MRI (C4a=18, C4b=17, C4c=8,C5=3). Of 46 lesions, 37 were masses and 9 were non-mass enhancement lesions. Thirty-two lesions showed a continuous kinetics curve, 11 were plateau and 3 were washout. Conclusions: Our study showed success in MRI-guided breast lesion wire localization with a satisfactory cancer diagnosis rate of 30.4%. MRI-guided wire localization breast lesion open biopsy is a safe and effective tool for the workup of suspicious lesions seen on breast MRI alone without major complications. This may contribute to increasing the diagnosis rate of early breast cancer and improve the prognosis in Chinese women.

A study of automatic train operation by ATC system and fault tracing (ATC장치에 의한 자동운전 및 고장 추적에 관한 연구)

  • 김경식;강덕원;강리택;이종성
    • Proceedings of the KSR Conference
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    • 2002.10a
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    • pp.503-508
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    • 2002
  • According to passengers gain and headway's contraction, railway vehicle is required quick and correct running. The importance of ATC device was increased gradually, and also is acting important role in safe train running and efficient use in this reason. Now, railway vehicle that is manufactured or is remodeled are designed to most automatic driving system, and ATC device design direction than other device of railway vehicle influences to whole system in this reason. Also, according as system becomes complicated gradually, importance of fault tracing function fur ATC device is emphasized gradually, and in this reason research about efficient fault tracing method is to act important role heightening reliability of ATC device. In this document, that analyzing about result through examination of automatic train operation system of localization model ATC device(SG-100) and application example, and do so that investigate about efficient fault Bracing.

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WMPS: A Positioning System for Localizing Legacy 802.11 Devices

  • Gallo, Pierluigi;Garlisi, Domenico;Giuliano, Fabrizio;Gringoli, Francesco;Tinnirello, Ilenia
    • IEIE Transactions on Smart Processing and Computing
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    • v.1 no.2
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    • pp.106-116
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    • 2012
  • The huge success of location-aware applications has called for the rapid development of an alternative positioning system to the global positioning system (GPS) for indoor localization based on existing technologies, such as 802.11 wireless networks. This paper proposes the Wireless MAC Processor Positioning System (WMPS), which is a localization system running on off-the-shelf 802.11 Access Points and based on the time-of-flight ranging of users' standard terminals. This paper proves through extensive experiments that the propagation delays can be measured with the accuracy required by indoor applications despite the different noise components that can affect the result: latencies of the hardware transreceivers, multipath, ACK jitters and timer quantization. Key to this solution is the choice of the Wireless MAC Processor architecture, which enables a straightforward implementation of the ranging subsystem directly inside the commercial cards without affecting the basic DCF channel access algorithm. In addition to the proposed measurement framework, this study developed a simple and effective localization algorithm that can work without requiring any preliminary calibration or device characterization. Finally, the architecture allows the measurement methodology to be adjusted as a function of the network load or propagation environments at the run time, without requiring any firmware update.

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