• Title/Summary/Keyword: Radio-based

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The Tunnel Lane Positioning System of a Autonomous Vehicle in the LED Lighting (LED 조명을 이용한 자율주행차용 터널 차로측위 시스템)

  • Jeong, Jae hoon;Lee, Dong heon;Byun, Gi-sig;Cho, Hyung rae;Cho, Yoon ho
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.16 no.1
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    • pp.186-195
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    • 2017
  • Recently, autonomous vehicles have been studied actively. There are various technologies such as ITS, Connected Car, V2X and ADAS in order to realize such autonomous driving. Among these technologies, it is particularly important to recognize where the vehicle is on the road in order to change the lane and drive to the destination. Generally, it is done through GPS and camera image processing. However, there are limitations on the reliability of the positioning due to shaded areas such as tunnels in the case of GPS, and there are limitations in recognition and positioning according to the state of the road lane and the surrounding environment when performing the camera image processing. In this paper, we propose that LED lights should be installed for autonomous vehicles in tunnels which are shaded area of the GPS. In this paper, we show that it is possible to measure the position of the current lane of the autonomous vehicle by analyzing the color temperature after constructing the tunnel LED lighting simulation environment which illuminates light of different color temperature by lane. Based on the above, this paper proposes a lane positioning technique using tunnel LED lights.

A Study on the Use of Supplementary Teaching Materials and Implements in the High School Home Economics Education (고등학교 가정과 교육에서 보조학습 교재.교구의 활용실태 연구)

  • 조은경;김용숙
    • Journal of Korean Home Economics Education Association
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    • v.9 no.1
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    • pp.1-17
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    • 1997
  • This study was conducted to obtain basic materials to improve the teaching method of Home Economics by theoretically looking into the supplementary teaching materials or implements usable in teaching Costume History area. And based on these data, the types and the applications of the supplementary teaching materials or implements highschool owned were examined. The subjects of this study were 111 Home Economics and Housework curriculum highschool teachers who give a lecture in the country by using self-administered questionnaires. SAS program was used to calculate frequency, percentage, average, standard deviation, and $\chi$(sup)2-test analysis. The results of the study were as follows; 1. Most of the highschool teachers used the school expenses for experiments in preparing the supplementary teaching materials or implements. 2. Of the supplementary teaching materials and implements concerning Costume History, visual implements such as slides and pictures were the mostly owned. CD and audio implements as cassette-tapes were not used. 3. Most of the teachers recognized the importance of the audio-visual teaching materials and implements concerning Costume History. 4. Among the audio-visual materials and implements concerning Costume History by which can be made by school teachers of Home Economics and Housework curriculum, the mostly used one was ‘cutting pictorials from magazines and newspapers’, and the next were ‘orbital materials’, and ‘copy the pictorials’, and the least was ‘recording from the radio’. 5. Most of the annual expenses assigned to the department of Home Economics was used in cooking practice, and the least of the expenses was assigned in buying audio-visual teaching materials and implements. 6. Time assigned to the area of Home Economics was for the most part one or two hours per week, and among this, time assigned to the history of western costume and the history ok korean costume was for the most part five to eight hours. 7. The areas that the highschool teachers felt difficulties mostly during clothing and textiles curriculum were ‘textiles’and the next were ‘knitting’, ‘western costume history’, and ‘korean clothing construction’. 8. The difficulties the highschool teachers faced while teaching Costume History were mostly that ‘the pictorials in the text is not fully explainable’, the next were ‘most of the supplementary teaching materials or implements are not owned’, ‘have to explain very much in a short time’, and ‘the lectural explanation is insufficient’. 9. The solution for the difficulties that the highschool teachers faced while teaching Costume History was mostly ‘the information, on which audio-visual materials and implements are distributed in the market, should be easy to obtain’, the next opinions were ‘the school should provide enough experiment and practice expenses to buy audio-visual materials and implements’, and ‘education facilities of the Home Economics Department should be the main aspects in improving the teaching methods and should give special lectures about it’.

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Performance Evaluation of Inter-Sector Collaborative PF Schedulers for Multi-User MIMO Transmission Using Zero Forcing (영점 강제 다중 사용자 MIMO 전송 시 셀 간 정보 교환을 활용한 협력적 PF 스케줄러의 성능 평가)

  • Lee, Ji-Won;Sung, Won-Jin
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.47 no.2
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    • pp.40-46
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    • 2010
  • Multi-user MIMO (Multiple-Input Multiple-Output) systems require collaborative PF schedulers to improve the performance of the log sum of average transmission rates. While the performance of single cell based conventional PF schedulers has been evaluated over various channel conditions, scheduling algorithms by multiple base stations which select multiple users over a given time frame and their performance require further investigations. In this paper, we apply a collaborative PF scheduler to the distributed multi-user MIMO system, which assigns radio resources to multiple users by exchanging user channel information from base stations located in three adjacent sectors. We further evaluate its performance in terms of the log sum of average transmission rates. The performance is compared to that of the full-search collaborative PF scheduler which searches over all possible combinations of user groups, and that of a parallel PF scheduler that determines users without channel information exchange among base stations. We show the log sum of average transmission rates of the collaborative PF scheduler outperforms that of the parallel PF scheduler in low percentile region. In addition, the collaborative PF scheduler exhibits a negligible performance degradation when compared to the full-search collaborative PF scheduler while a significant reduction of the computational complexity is achievable at the same time.

A Service Identification Scheme for the Convergence of Ubiquitous Sensor Networks (유비쿼터스 센서 네트워크 융합을 위한 서비스 식별 체계)

  • Uhm, Huy-Jung;Eun, Seong-Bae;Jun, Jung-Ho;Kang, Gwon-U;Ju, Yong-Wan
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.48 no.6
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    • pp.104-113
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    • 2011
  • While converging USN Services, a single physical infrastructure can be used in several services and in several physical infrastructures can make up a single service. Therefore the physical infrastructure and service have to manage separately for effective convergence of USN Services. However, established Identification Scheme is not suitable to distinguish various services that USN provides. This paper suggests USN Service Identification Scheme that can be separated and managed. Through USN Service Identification Scheme suggested, firstly, it is possible to obtain Service Identification Scheme utilizing various technology such as RFID TAG, QR Code, radio broadcasting, etc. because it is possible to process USN Service Identification Scheme. Secondly, it is easy to mange the service, develope the user application program and interlock with established USN Standard technique as view from service provider. Thirdly, it is possible to manage systematically USN Service. Fourthly, users can search USN Service easily, so it can contribute actively for invigoration of USN service. This thesis, firstly, has analyzed about standard related USN Service and USN Identification Scheme. Secondly, this has suggested brand-new USN Service Identification Scheme based on established USN Identification Scheme.

A study on the AVI/AEI International standardization and development of the Korea standard (AVI/AEI 국제표준 동향과 국내표준 개발에 관한 연구)

  • Kim Woong-Yi;Kang Kyung-Woo
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.2 no.1 s.2
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    • pp.1-13
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    • 2003
  • This International Standard establishes an AVI/AEI System based on radio frequency technologies. This system is intended for general application in ITS. Specially, It allows the transfer of the identification codes and further information about equipment and vehicles used in intermodal transport into such CVO and information systems related to Intermodal Transport processes. The aim of this standard is to define, describe and specify Architecture, System Parameters, Numbering/ Data structures and interface related to an AVI/AEI system to provide an enabling Standard, which, whilst allowing the system specifier to determine the performance levels and operating conditions, provides a framework for nominal interoperability. The Standard is to establish a common framework to achieve unambiguous identification in AVI/AEI applications. Thes is AVI/AEI is designed to be an 'enabling' structure to allow interoperability between different commercial systems, and not prescriptive in determining any one system. The ISO TC204 WG4 has eight active work items. A new WI on ERI is progressing quickly; three WIs for the road environment and four multimodal WIs are under development. All Work Items are joint between CEN TC278 and ISO TC204 according to the Vienna Agreement, with CEN in the lead. The work is progressing with some delay. For all the work items, the countries who have appointed experts we: Australia, Austria, Belgium, Canada, Czech, Denmark France, Germany, Japan, Korea, the Netherlands, Norway, Spain, Sweden, UK and USA. There are 30 registered experts. The study focus on the AVI/AEcl standardization and developing of the Korea standard

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Relay Protocol in DSRC System (DSRC 시스템에서 릴레이 프로토콜)

  • Choi Kwang-Joo;Choi Kyung-Won;Cho Kyong-Kuk;Yoon Dong-Weon;Park Sang-Kyu
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.43 no.9 s.351
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    • pp.32-39
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    • 2006
  • 5.8GHz DSRC(Dedicated Short Range Communications) is a short to medium range communications service that supports both public safety and private operations in roadside to vehicle and vehicle communication. However the 5.8GHz frequency may cause the shadowing effect or communication blocking problem when there is an obstacle or another vehicle between RSE (Road Side Equipment) and OBE (On Board Equipment). In this paper, to solve this problem of the 5.8GHz DSRC, we propose a relay protocol based on the standard of DSRC radio communication between RSE and OBE in the 5.8GHz band made by TTA (Telecommunication Technology Association). By using the proposed relay protocol to DSRC system and intervehicle communication, we also consider a fixed relay protocol and mobile relay protocol. We expect to apply this relay protocol for the DSRC intervehicle communication and video communication between drivers and safe distance among vehicles in the near future.

A MB-OFDM UWB Receive Design and Evaluation Using 4. Parallel Synchronization Architecture (4 병렬 동기 구조를 이용한 MB-OFDM UWB 수신기 설계 및 평가)

  • Shin Cheol-Ho;Choi Sangsung;Lee Hanho;Pack Jeong-Ki
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.16 no.11 s.102
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    • pp.1075-1085
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    • 2005
  • The purpose of this paper is to design the architecture for synchronization of MB-OFDM UWB system that is being processed the standardization for Alt-PHY of WPAN(Wireless Personal Area Network) at IEEE802.15.3a and to analyze the implementation loss due to 4 parallel synchronization architecture for design or link margin. First an overview of the MB-OFDM UWB system based on IEEE802.15.3a Alt-PHY standard is described. The effects of non-ideal transmission conditions of the MB-OFDM UWB system including carrier frequency offset and sampling clock offset are analyzed to design a full digital architecture for synchronization. The synchronization architecture using 4-parallel structure is then proposed to consider the VLSI implementation including algorithms for carrier frequency offset and sampling clock offset to minimize the effects of synchronization errors. The overall performance degradation due to the proposed synchronization architecture is simulated to be with maximum 3.08 dB of the ideal receiver in maximum carrier frequency offset and sampling clock offset tolerance fir MB-OFDM UWB system.

OPTICAL MULTI-CHANNEL INTENSITY INTERFEROMETRY - OR: HOW TO RESOLVE O-STARS IN THE MAGELLANIC CLOUDS

  • Trippe, Sascha;Kim, Jae-Young;Lee, Bangwon;Choi, Changsu;Oh, Junghwan;Lee, Taeseok;Yoon, Sung-Chul;Im, Myungshin;Park, Yong-Sun
    • Journal of The Korean Astronomical Society
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    • v.47 no.6
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    • pp.235-253
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    • 2014
  • Intensity interferometry, based on the Hanbury Brown-Twiss effect, is a simple and inexpensive method for optical interferometry at microarcsecond angular resolutions; its use in astronomy was abandoned in the 1970s because of low sensitivity. Motivated by recent technical developments, we argue that the sensitivity of large modern intensity interferometers can be improved by factors up to approximately 25 000, corresponding to 11 photometric magnitudes, compared to the pioneering Narrabri Stellar Interferometer. This is made possible by (i) using avalanche photodiodes (APD) as light detectors, (ii) distributing the light received from the source over multiple independent spectral channels, and (iii) use of arrays composed of multiple large light collectors. Our approach permits the construction of large (with baselines ranging from few kilometers to intercontinental distances) optical interferometers at the cost of (very) long-baseline radio interferometers. Realistic intensity interferometer designs are able to achieve limiting R-band magnitudes as good as $m_R{\approx}14$, sufficient for spatially resolved observations of main-sequence O-type stars in the Magellanic Clouds. Multi-channel intensity interferometers can address a wide variety of science cases: (i) linear radii, effective temperatures, and luminosities of stars, via direct measurements of stellar angular sizes; (ii) mass-radius relationships of compact stellar remnants, via direct measurements of the angular sizes of white dwarfs; (iii) stellar rotation, via observations of rotation flattening and surface gravity darkening; (iv) stellar convection and the interaction of stellar photospheres and magnetic fields, via observations of dark and bright starspots; (v) the structure and evolution of multiple stars, via mapping of the companion stars and of accretion flows in interacting binaries; (vi) direct measurements of interstellar distances, derived from angular diameters of stars or via the interferometric Baade-Wesselink method; (vii) the physics of gas accretion onto supermassive black holes, via resolved observations of the central engines of luminous active galactic nuclei; and (viii) calibration of amplitude interferometers by providing a sample of calibrator stars.

Differences in Breast and Cervical Cancer Screening Rates in Jordan among Women from Different Socioeconomic Strata: Analysis of the 2012 Population-Based Household Survey

  • Al Rifai, Rami;Nakamura, Keiko
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.15
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    • pp.6697-6704
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    • 2015
  • Background: The burden of breast and cervical cancer is changing over time in developing countries. Regular screening is very important for early detection and treatment. In this study, we assessed inequalities in breast and cervical cancer screening rates in women according to household wealth status, and analyzed the potential predictors associated with a low cancer screening rate in Jordan. Materials and Methods: A nationwide populationbased cross-sectional survey collected information on different variables at the national level. All ever-married women (the phrase is used throughout the text to refer to women who had ever married) aged 15-49 years were included in the survey. Analysis of breast self-examination (BSE) and clinical breast examination (CBE) at least once in the previous year was carried out in 11,068 women, while lifetime Pap-smear testing was carried out in 8,333 women, aged 20-49 years. Results: Over 39% and 19% of ever-married Jordanian women reported having undergone a breast examination during the previous year and Pap smear examination at least once in their lifetime, respectively. The rate of BSE in the previous year was 31.5%, that of CBE in the previous year was 19.3%, and that of Pap smear examination at least once in life was 25.5%. The adjusted OR was higher for performing BSE (aOR 1.22, 95% CI 1.04-1.43), undergoing CBE (aOR 1.31, 95% CI 1.08-1.60) and undergoing Pap smear examination (aOR 2.38, 95% CI 1.92-2.93) among women in the highest wealth-index quintile as compared to those in the lowest quintile. The concentration index was 0.11 for BSE, 0.01 for CBE, and 0.27 for Pap smear examination. Women in their twenties, living in rural or the southern region of Jordan, with an elementary school education or less, who listened to the radio or read the newspaper not more than a few times a year, and nulliparous women were less likely to undergo breast and cervical cancer screening. Conclusions: The rates of breast and cervical cancer screening are low in Jordan. Reducing the sociodemographic and economic inequalities in breast and cervical cancer screenings requires concerted outreach activities for women living under socially deprived conditions.

Design of active beam steering antenna mounted on LEO small satellite (저궤도 소형위성 탑재용 빔 조향 능동 다이폴 안테나 설계)

  • Jeong, Jae-Yeop;Park, Jong-Hwan;Woo, Jong-Myung
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.16 no.5
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    • pp.197-203
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    • 2016
  • In this paper, the dipole antenna that can control a beam steering were designed for attaching on LEO(Low Earth Orbit) small satellite. The proposed antenna was based on Yagi-Uda antenna. The parasitic element was proposed as a T-shape. Depending on the state of open or short at the end of a vertical element, we can choose a characteristic of the parasitic element with fixing a vertical element length of the parasitic element. Using this characteristic, we designed the director element and reflector element. The proposed antenna was designed to receive UHF 436.5 MHz. Antenna gain was chosen by link budget between one satellite and the other satellite or between the satellite and the ground station. By changing a vertical element length which is the largest variable that chooses an antenna characteristic, we confirmed that ${\lambda}/2$ length transformer has a result that improve 0.5 dB in comparison ${\lambda}/4$ length transformer from maximum gain direction. In production, we made an on/off switch composed of a diode, capacitor, and inductor control an open and short at the end of the parasitic element. As a result, the gain of antenna used in a link between one satellite and the other satellite had average 5.92 dBi. And the gain of antenna used in a link between the satellite and the ground station had average 0.99 dBi.