• Title/Summary/Keyword: IPDL

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Performance Improvement of Wireless Positioning System Using IC-IPDL Method (IC-IPDL 기법을 이용한 무선 측위 시스템의 성능 개선)

  • 김상헌;정양석;윤대희;이충용
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.27 no.2A
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    • pp.124-129
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    • 2002
  • We propose a wireless positioning system using IC-IPDL method that exploits the modified-IPDL method and the interference cancellation techniques to improve hearability. In the proposed system, IPDL method is modified to maintain the transmission of CPICH for stability of CDMA network Simultaneously in mobile CPICH is cancelled out using the interference cancellation techniques for improving hearability. The simulation results showed that the proposed location system has a compatible performance to the standard IPDL method though CPICH exists during idle period.

IC-IPDL Method for Improving Hearability of Wireless Positioning System (무선 측위 시스템의 hearability 개선을 위한 IC-IPDL 기법)

  • 김상헌;정양석;윤대희;이충용
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.27 no.2A
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    • pp.109-115
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    • 2002
  • We propose IC-IPDL method, in order to improve hearability which is the fundamental problem of cellular-based location systems. The proposed method improves hearability by using interference cancellation technique for CPICH and modified-IPDL method for other downlink channels. The simulation results showed that IC-IPDL method has a similar performance of the case using standard IPDL method though CPICH exists during idle period.

Performance Analysis of IPDL Methods Using High Resolution Channel Estimation Technique for W-CDMA systems (W-CDMA 시스템에서 고해상 채널 추정을 이용한 IPDL 기법의 무선 측위 성능분석)

  • 朴雲龍;崔州平;李元澈
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.39 no.6
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    • pp.10-10
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    • 2002
  • This paper introduces the high-resolution channel estimation technique which are used to estimate the first arrival multipath delay component. The proposed technique yields the precise estimate of the first time arrival which is directly related to the performance of TDOA-based position location. The proposed technique utilizes the transformed auto-correlation function of received common pilot signal in frequency domain, its samples compose the hermitian Toeplitz matrix at sequel. Then the time delay components could be estimated with precision by the analysis of eigen-structure of corresponding matrix. In this paper, obeying the modified CODIT model, the performance of the PR-IPDL(Pseudo Random-Idle Period Downlink) and TA-IPDL(Time Aligned-Idle Period Downlink considered as 3GPP position location technique will be exploited systematically through the computer simulations with applying the proposed technique.

Performance Analysis of IPDL Methods Using High Resolution Channel Estimation Technique for W-CDMA systems (W-CDMA 시스템에서 고해상 채널 추정을 이용한 IPDL 기법의 무선 측위 성능분석)

  • Park, Un-Yong;Choe, Ju-Pyeong;Lee, Won-Cheol
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.39 no.6
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    • pp.268-276
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    • 2002
  • This paper introduces the high-resolution channel estimation technique which are used to estimate the first arrival multipath delay component. The proposed technique yields the precise estimate of the first time arrival which is directly related to the performance of TDOA-based position location. The proposed technique utilizes the transformed auto-correlation function of received common pilot signal in frequency domain, its samples compose the hermitian Toeplitz matrix at sequel. Then the time delay components could be estimated with precision by the analysis of eigen-structure of corresponding matrix. In this paper, obeying the modified CODIT model, the performance of the PR-IPDL(Pseudo Random-Idle Period Downlink) and TA-IPDL(Time Aligned-Idle Period Downlink considered as 3GPP position location technique will be exploited systematically through the computer simulations with applying the proposed technique.

Effects of substance P on mineralization markers and heme oxygenase-1 Expression in human immortalized periodontal ligament cells

  • Cho, You-Min;Suh, Chung-Hwan;Chun, Sang-Woo;Kim, Eun-Cheol;Kang, Kyung-Hwa
    • International Journal of Oral Biology
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    • v.33 no.4
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    • pp.131-135
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    • 2008
  • Substance P (SP) is known to be expressed in the nerve fibers of dental pulp and periodontal tissues. It was recently reported that SP expression increased in response to orthodontic force. In the present study, we investigated the effect of SP on expression of mineralization markers and heme oxygenase-1 (HO-1) in human immortalized periodontal ligament (IPDL) cells. Cell viability was measured using a 3,4,5-dimethylthiazol-2-yl-2,5-diphenyl tetrazolium bromide (MTT) assay. The expression of mineralization markers, including alkaline phosphatase (ALP), osteonectin (ON) and bone sialoprotein (BSP), and heme oxygenase-1 (HO-1) was assessed by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot analysis. SP did not significantly change human IPDL cell viability, with the exception of the 24 hour treatment group. Treatment of human IPDL cells with $10^{-10}$ to $10^{-4}M$ SP upregulated mineralization marker and HO-1 expression in a time- and concentration-dependent manner. Our results suggest that SP may modulate osteoblastic cell differentiation of human IPDL cells through a mechanism involving HO-1 expression.

DB가이드 - PCT(특허협력조약) 데이터베이스

  • Lee, Ik-Sang
    • Digital Contents
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    • no.11 s.66
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    • pp.74-78
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    • 1998
  • PCT는 WIPO IPDL(WIPO Intellectual Property Digital Library) 프로젝트에 의해 만들어진 데이터베이스이며, PCT를 통해 출원된 국제특허자료를 인터넷을 통해 무료로 검색해 볼 수 있다.

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High Resolution Time Delay Estimation Technique for Position Location

  • Park, Woon-Yong;Lee, Won-Ro;Kong, Seung-Hyun;Lee, Won-Cheol
    • Proceedings of the IEEK Conference
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    • 2002.07c
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    • pp.1610-1613
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    • 2002
  • This paper analyses the performance of PE-IPDL technique fer the wireless mobile position location, which have been considered as a major candidate for 3GPP position location due to its capability in mitigating the hearability problem and DOP problem. To improve the location performance of PE-IPDL, this paper introduces the high-resolution estimation technique for the first arrival multipath delay, and simulation results verify its superiority. For a systematic analysis of above location method, its performances are exploited by obeying the CODIT channel model specially bad urban channel environment. Simulation results verify its efficiency of enhancing the degree of accuracy in positioning.

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Effect of Chemical Structure on the Properties of UV-cured Polyurethane Acrylates Films

  • Kwon, Ji-Yun;Yoo, Hye-Jin;Kim, Han-Do
    • Fibers and Polymers
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    • v.2 no.3
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    • pp.141-147
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    • 2001
  • The effect of compositions of isophorone diisocyanate (IPDl)/4.4'-diphenylmethane diisocyalate (MDI) and polypropylene oxide diol (PPG, $M_w$: 3000)/1,4-butane diol (BD) on the properties of UV-cured polyurethane acrylate films based on 2-hydroxyethyl acrylate (HEA) was examined. UV-curable polyurethane acrylates were formulated from the prepolymer. trimethylol propane triacrylate (TMPTA) as a reactive diluent, and 1-hydroxycyclohexyl ketone (Irgacure 184) as a photoinitiator. Dynamic mechanical thermal properties and elastic properties of UV-cured polyurethane acrylates was fecund to depend on the chemical composition of IPDl/MDl and PPG/BD. As the BD content increased, the tensile storage modulus of all series samples increased significantly. The storage modulus increased in the order of samples A (IPDI based samples)> samples B (IPDI/MDl (7/3 molar ratio) based samples) > samples C (IPDI/MDl (5/5 molar ratio) based samples at the same composition. Two distinct louts modulus peaks for all samples are observed owing to the softs segment glass transition temperature ($T_gh$) and hard segment glass transition temperature ($T_gh$). The difference between $T_gh$, and $T_gh$, (Δ$T_g$) increases in the order of A > B > C at the same composition. In cycle test, the initial onset strain (%) was found to decrease with increasing BD content in PPG/BD and with increasing MDI content in IPDI/MDl.

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Analyzing Patent Trend of Mibyeong (미병 특허 동향 조사)

  • Jin, Hee-Jeong;Lee, Youngseop;Yu, Hana;Lee, Siwoo
    • Journal of Society of Preventive Korean Medicine
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    • v.19 no.3
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    • pp.21-28
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    • 2015
  • Objective : The purpose of this study was to analyze for the patent application tendency in mibyeong. Mibyeong is a concept in Korean Medicine meaning sub-health state, and treatment of mibyeong can be understood as preventive medicine. This concept laid a foundation for the development of Korean, Japanese and Chinese traditional medicine. In this paper, we describe a meaningful data for efficient R&D through patent analysis of mibyeong focusing on the Korea, Japan and China. Method : We collected patents about mibyeong using Focust, IPDL search tools. We analyzed patents according to the year, topic, country and etc. Results & Conclusion : We collected 1,577 patents and selected 807 patents as useful patents. After detailed analysis on mibyeong patent, we got to know that research about mibyeong was a growing field. In the collected patents, the patents on treatment device(except treatment compositions) were the majority and system of providing information were the second largest. We think that the mibyeong field is growing at a fast pace with high activity, and this research should be updated annually.

Evaluation of the radiopacity and cytotoxicity of resinous root canal sealers (레진계 근관충전실러의 방사선 불투과성 및 세포 독성에 대한 평가)

  • Kim, Chang-Kyu;Ryu, Hyun-Wook;Chang, Hoon-Sang;Lee, Byung-Do;Min, Kyung-San;Hong, Chan-Ui
    • Restorative Dentistry and Endodontics
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    • v.32 no.5
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    • pp.419-425
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    • 2007
  • The aim of this study was to evaluate the radiopacity and cytotoxicity of three resin-based (AH 26, EZ fill and AD Seal), a zinc oxide-eugenol-based (ZOB Seal), and a calcium hydroxide-based (Sealapex) root canal sealers. Specimens, 10 mm in diameter and 1 mm in thickness, were radiographed simultaneously with an aluminum step wedge using occlusal films, according to ISO 6876/2001 standards. Radiographs were digitized, and the radiopacity of sealers was compared to the different thicknesses of the aluminum step wedge, using the Scion image software. Using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, the cytotoxicity of each material was determined in immortalized human periodontal ligament (IPDL) cells. The results demonstrated that EZ fill was the most radiopaque sealer, while Sealapex was the least radiopaque (p < 0.05). AH 26, AD Seal and ZOB Seal presented intermediate radiopacity values. All the materials evaluated, except for Sealapex, presented the minimum radiopacity required by ISO standards. The cell viabilities of resin-based root canal sealers were statistically higher than that of other type of root canal sealers through the all experimental time. Further, EZ fill showed statistically lower cell viability in 24 and 48 hours compared to AD Seal and in 72 hours compared to all other resin-based root canal sealers. However, there was no correlation between the radiopacity and cytotoxicity of three resin-based root canals sealers (p > 0.05). These results indicate that resin-based root canal sealer is more biocompatible and has advantage in terms of radiopacity.