• Title/Summary/Keyword: Real time transport

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Hardware Channel Decoder for Holographic WORM Storage (홀로그래픽 WORM의 하드웨어 채널 디코더)

  • Hwang, Eui-Seok;Yoon, Pil-Sang;Kim, Hak-Sun;Park, Joo-Youn
    • Transactions of the Society of Information Storage Systems
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    • v.1 no.2
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    • pp.155-160
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    • 2005
  • In this paper, the channel decoder promising reliable data retrieving in noisy holographic channel has been developed for holographic WORM(write once read many) system. It covers various DSP(digital signal processing) blocks, such as align mark detector, adaptive channel equalizer, modulation decoder and ECC(error correction code) decoder. The specific schemes of DSP are designed to reduce the effect of noises in holographic WORM(H-WORM) system, particularly in prototype of DAEWOO electronics(DEPROTO). For real time data retrieving, the channel decoder is redesigned for FPGA(field programmable gate array) based hardware, where DSP blocks calculate in parallel sense with memory buffers between blocks and controllers for driving peripherals of FPGA. As an input source of the experiments, MPEG2 TS(transport stream) data was used and recorded to DEPROTO system. During retrieving, the CCD(charge coupled device), capturing device of DEPROTO, detects retrieved images and transmits signals of them to the FPGA of hardware channel decoder. Finally, the output data stream of the channel decoder was transferred to the MPEG decoding board for monitoring video signals. The experimental results showed the error corrected BER(bit error rate) of less than $10^{-9}$, from the raw BER of DEPROTO, about $10^{-3}$. With the developed hardware channel decoder, the real-time video demonstration was possible during the experiments. The operating clock of the FPGA was 60 MHz, of which speed was capable of decoding up to 120 mega channel bits per sec.

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Design and Implementation of the Traffic and Travel Information Service for Terrestrial DMB System (T-DMB에서의 교통여행정보서비스 설계 및 구현)

  • Kwon, Dae-Bok;Chae, Young-Seok
    • Journal of Broadcast Engineering
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    • v.12 no.3
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    • pp.203-213
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    • 2007
  • DMB video/audio service was successfully launched. DMB data service is a matter of primary concern now. The TTI(Traffic and Travel Information) service is considered as a killer application of the data service. Tn this paper, we propose a method for design and implementation of the broadcasting system for TTI service. The proposed TTI service system consists of an authoring tool, the DB module, the Transmission module and Monitoring module. This system satisfies the national TTA standards of the Traffic and Travel Information data services for terrestrial DMB; TPEG(Transport Protocol Experts Group) platform. The system was designed to support real-time automatic transmission for CTT and CTT SUM, and non real-time authoring & automatic transmission for POI and SDI, and was focused on the capability to make high-quality contents efficiently and to send them to the data inserter reliably. The performance of the implemented system was proven through the conformance tests with the various commercial receivers. After the continuous upgrade, the system is being used in commercial service.

Implementation of Road Weather Information System Supporting Intelligent Transportation Systems Based on USN (센서 네트워크 기반의 지능형 교통 시스템 지원을 위한 RWIS 구현)

  • Park, Hyun-Moon;Park, Soo-Huyn;Park, Woo-Chool;Seo, Hae-Moon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.35 no.3B
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    • pp.485-492
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    • 2010
  • Intelligent Transport System(ITS) has been studied in various systems, such as road environment information offering, vehicle short-range wireless/wire communication, vehicle collision preventing and pedestrian safety offering systems. Related to this, the USN technology based on the sensing accuracy for motorists and pedestrians safety, the information reliability, the maintenance and convenience for Sensor Network is highlighted. This study uses various sensors to construct USN to the road, and connect it to the developed RSU so it collects the real-time road environment information and offers it to OBU and Traffic Control Surveillance Center with Road Weather Information System. RSU collects roadside information for driver's safety and analyzes it to offer IP and beacon service according to the service priority to OBU & upper layer terminal. In the upper layer terminal it is developed the IP based Settop Box application program to offer the urban traffic information & road environment, and environment sensor error, etc. Finally, RWIS develops the real-time collection of roadside information to complement the driver's safety to the intelligent traffic system, and presents various service modes with technology convergence.

An experimental study of particle deposition from high temperature gas-particle flows (고온의 기체 입자 유동으로부터 입자부착 현상에 관한 실험적 연구)

  • 김상수;김용진
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.11 no.3
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    • pp.501-508
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    • 1987
  • Experimental studies of particle (TiO$\_$2/) deposition from the laminar hot gas particle flow (about 1565K) onto the cold wall surface (about 1215K-1530K) were carried out by the 'real time' laser light reflectivity method (LLRM) and the photographs of scanning electron microscope(SEM). The LLRM was used for the measurement of thermophoretic deposition rates of small particles (d$\_$p/<3.mu.m), and the photographs of SEM were used for determining what factors control the collection of particles having diameters ranging from 0.2 to 30 microns. Two phenomena are primarily responsible for transport of the particles across the laminar boundary layers and deposition: (1) particle thermophoresis (i.e. particles migration down a temperature gradient), and (2) particle inertial impaction, the former effect being especially larger factor of the particle deposition in its size over the range of 0.2 to 1 microns. And also, this study indicates that thermophoresis can be important for particles as large as 15 microns. Beyond d$\_$p/=16.mu.m, this effect diminishes and the inertial impaction is taken into account as a dominant mechanism of particle deposition. The results of present experiments found to be in close agreement with existing theories.

Implementation of Data Integrity Module in Wireless Internet Terminal for Mobile Customer Relationship Management(m-CRM) (m-CRM을 위한 무선인터넷단말기의 데이터무결성 모듈의 구현)

  • Park, Hyun-Cheol;Kim, Dong-Gyu
    • The KIPS Transactions:PartD
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    • v.11D no.2
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    • pp.485-494
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    • 2004
  • Recently, the wireless internet terminals like mobile phones or PDAs prevail in the management of customers. With such terminals, businessmen can get business data and information of customers in real time, in connection with mobile group wares. By the wireless terminals, customers can conveniently get information of goods, search purchase sites, and give orders and do settlement. This paper aims to present the safe data integrity modules of the wireless internet terminal, for service providing correct real-time promotion information, by using users' disposition, situation, Purchase information. This study aims to suggest an implementation methodology of security module for data integrity of mobile internet terminal. This is based on the WTLS of WAP Protocol. This security module is expected to achieve central role in conversion of wireless internet environment and emphasis of encryption technology and safe and calculable wireless communication environment construction

The Changes of P-glycoprotein Activity by Interferon-γ and Tumor Necrosis Factor-α in Primary and Immortalized Human Brain Microvascular Endothelial Cells

  • Lee, Na-Young;Rieckmann, Peter;Kang, Young-Sook
    • Biomolecules & Therapeutics
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    • v.20 no.3
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    • pp.293-298
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    • 2012
  • The purpose of this study was to investigate the modification of expression and functionality of the drug transporter P-glycoprotein (P-gp) by tumor necrosis factor-alpha (TNF-${\alpha}$) and interferon-gamma (IFN-${\gamma}$) at the blood-brain barrier (BBB). We used immortalized human brain microvessel endothelial cells (iHBMEC) and primary human brain microvessel endothelial cells (pHBMEC) as in vitro BBB model. To investigate the change of p-gp expression, we carried out real time PCR analysis and Western blotting. To test the change of p-gp activity, we performed rhodamin123 (Rh123) accumulation study in the cells. In results of real time PCR analysis, the P-gp mRNA expression was increased by TNF-${\alpha}$ or IFN-${\gamma}$ treatment for 24 hr in both cell types. However, 48 hr treatment of TNF-${\alpha}$ or IFN-${\gamma}$ did not affect P-gp mRNA expression. In addition, co-treatment of TNF-${\alpha}$ and IFN-${\gamma}$ markedly increased the P-gp mRNA expression in both cells. TNF-${\alpha}$ or IFN-${\gamma}$ did not influence P-gp protein expression whatever the concentration of cytokines or duration of treatment in both cells. However, P-gp expression was increased after treatments of both cytokines together in iHBMEC cells only compared with untreated control. Furthermore, in both cell lines, TNF-${\alpha}$ or IFN-${\gamma}$ induced significant decrease of P-gp activity for 24 hr treatment. And, both cytokines combination treatment also decreased significantly P-gp activity. These results suggest that P-gp expression and function at the BBB is modulated by TNF-${\alpha}$ or/and IFN-${\gamma}$. Therefore, the distribution of P-gp depending drugs in the central nervous system can be modulated by neurological inflammatory diseases.

Analysis of Take-over Time and Stabilization of Autonomous Vehicle Using a Driving Simulator (드라이빙 시뮬레이터를 이용한 자율주행자동차 제어권 전환 소요시간 및 안정화 특성 분석)

  • Park, Sungho;Jeong, Harim;Kwon, Cheolwoo;Kim, Jonghwa;Yun, Ilsoo
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.18 no.4
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    • pp.31-43
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    • 2019
  • Take-overs occur in autonomous vehicles at levels 3 and 4 based on SAE. For safe take-over, it is necessary to set the time required for diverse drivers to complete take-over in various road conditions. In this study, take-over time and stabilization characteristics were measured to secure safety of take-over in autonomous vehicle. To this end, a virtual driving simulator was used to set up situations similar to those on real expressways. Fifty drivers with various sexes and ages participated in the experiment where changes in traffic volume and geometry were applied to measure change in takeover time and stabilization characteristics according to various road conditions. Experimental results show that the average take-over time was 2.3 seconds and the standard deviation was 0.1 second. As a result of analysis of stabilization characteristics, there was no difference in take-over stabilization time due to the difference of traffic volume, and there was a significant difference by curvature changes.

Redesign and Performance Analysis of RTP(Real-time Transport Protocol) for Encryption of VoIP Media Information between Different Communication Networks (이종의 통신망 간에 VoIP 미디어 암호화를 위한 RTP(Real-time Transport Protocol)의 재설계 및 성능 분석)

  • Oh, Hyung-Jun;Park, Jae-Kyoung;Won, Yoo-Hun
    • Journal of the Korea Society of Computer and Information
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    • v.18 no.4
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    • pp.87-96
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    • 2013
  • In this paper, we suggest redesigned RTP protocol that is able to perform encryption of VoIP media information for single private network and between the different private networks. And we conduct a test for performance analysis. Such as SRTP or ZRTP methods have been used for VoIP media encryption. But, the existing encryption techniques have problem that can not perform end-to-end encryption between different private networks. In order to solve this problem, in this paper, we redesign RTP protocol. Redesigned RTP includes all information for encryption of VoIP media. Therefore the encryption is not affected by modification of SIP and SDP information that occurred in gateway. Also, redesigned RTP includes code for whether or not to apply encryption. By using the code, modification of RTP header from gateway prevents. As a result, redesigned RTP maintain the integrity and the RTP is able to perform encryption between the different private networks. Also, we conduct a test for performance analysis of SRTP, ZRTP and redesigned RTP.

A Study on Implementation Integrated Operation & Management System for Intermodal Connectivity Center (복합환승센터 통합운영시스템 구축방안에 관한 연구)

  • Kim, Sung-Eun;Lim, Jung-Sil;Moon, Young-Jun;Oh, Jae-Hak;Lee, Won-Young
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.10 no.4
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    • pp.24-35
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    • 2011
  • This paper demonstrates a methodology of integrated operation and management system for intermodal connectivity center (ICC), which is planning to be build up as a large scale public transit facilities for green growth strategy by the national government. The ICC needs to be capable of providing the integrated location based information for the public transit users in terms of collaborating a variety of transit modes and complex facility in a large scale center. Recently, the upcoming information and communication technologies enable to come up with real time information provision on nomadic and portable devices, i.e. smart phones and/or tablet PCs, as what the users actually need to get on demand. In order to provide the public transit users in ICC with the integrated information on their smart phones for example, the integrated operation and management system plays a key role to collect the data utilizing the wireless communication with real time location tracking and to manage them to be effective and operational sources for applicable personalized services. Thus, this paper defines a type of services, subsystems, and relevant technologies for the system integration so called a "Smart Garatagi Service" and shows a filed test demonstration case in the existing airport terminal, Gimpo Domestic.

A Study on Validation of Omnidirectional VR Treadmill by Comparison of Spatial Orientation Skills (공간지향 능력 비교를 통한 전방향 VR 트레드밀의 유효성 검증 연구)

  • Park, Hyunchul;Oh, Taeho;Kim, Inhi
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.21 no.5
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    • pp.15-27
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    • 2022
  • An omnidirectional VR treadmill is a highly-immersive walking simulator that allows identical body movements, such as walking, running, and sitting. However, the operation difficulty of an omnidirectional VR treadmill may cause data reliability problems. Therefore, this study aims to verify the effectiveness of a VR treadmill by comparing the ability to orient in the real and virtual worlds spatially. For this purpose, a rotating and searching path experiment was conducted with participants. This experiment showed that there was no statistically significant difference in the ability of the participants to orient in the real and virtual worlds spatially. In addition, the omnidirectional VR treadmill requires an adaptation time for the users due to the difficulty in the treadmill operation. However, there was no significant difference in the difficulty felt by the participants according to the adaptation time. Hence, these findings supported the possibility of collecting realistic walking data without safety concerns through an omnidirectional VR treadmill. Furthermore, this treadmill could be used in future research to solve problems directly related to pedestrian safety, such as the interaction between vehicles and pedestrians.