• Title/Summary/Keyword: MSA

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Performance Analysis of Reservation-based Multicast Scheduling Algorithm (예약기반 멀티캐스트 스케줄링 알고리즘의 성능분석)

  • 김도규
    • The Journal of Information Technology
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    • v.4 no.4
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    • pp.65-72
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    • 2001
  • This paper investigates the Performance of MSA l (group partition based reservation scheduling algorithm) and MSA ll (group based reservation scheduling algorithm) for multicast service in single-hop WDM networks. Simulation results show that MSA l produces lower mean packet delay than MSA ll when the channel resource is sufficient. However, when the channel resource is limited, MSA ll produces lower mean packet delay than MSA I when traffic load is heavy.

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A study on the Characteristics of S-type Transformed Microstrip Antenna of Mobile Communication (S-자형 변형된 마이크로스트립 안테나 특성에 관한 연구)

  • 박성일;고영혁
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.7 no.1
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    • pp.136-141
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    • 2003
  • In this paper, S-type transformed MSA and transformed MSA load by a Capacitor not to limit the electric force on the MSA is proposed. Bandwidth of the designed and fabricated S-type transformed MSA is 5.75% at the resonated frequency of 2.24GHz and the resonant frequency and bandwidth versus change of any arbitrary feed point is observed. also, E-plane and H-plane in the Measured radiation pattern characteristic of S-type transformed MSA is compared and analyzed.

Characteristics of 'ㄷ' type MSA Antenna for Frequency Shift (주파수 시프트용 'ㄷ'자형 MSA 안테나 특성)

  • Park, Sung-Il
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.13 no.5
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    • pp.235-238
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    • 2013
  • In this paper, ㄷ-type MSA for the QMSA structure is proposed. Transformed ㄷ-type MSA is stacked three dielectrics. ㄷ-type MSA structure was load upper & lower surface of the dielectric radiating patch and the ground turn-up left right capacity between parallel plates and radiating patch. Between the dielectric permittivity of the dielectric insert by 2.55 by varing the frequency was shifted. Designed ㄷ-type MSA sturcture of L1 was varied up to 1mm~22mm and frequency was shifted from 3.65GHz~3.84GHz. Also Designed ㄷ-type MSA was measured 1.95dBi maximum gain and bandwidth of 1.61 to 3.64%.

A Characteristics of Transformed Microstrip Antenna of Mobile Communication (이동통신용 변형된 마이크로스트립 안테나 특성)

  • 박성일;고영혁
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2002.11a
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    • pp.139-142
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    • 2002
  • 본 논문에서는 기존의 MSA의 구조를 변형하여 용량을 장하한 변형된 MSA구조와 S자형 변형된 MSA 구조를 제안했다. 용량을 장하한 변형된 MSA는 전기력선 형성에 제한 받지 않도록 방사패치와 접지면을 접어 올린 좌ㆍ우측 평행 평판과 방사패치 사이 용량을 장하하고, S자형 변형된 MSA는 방사패치쪽과 그라운드판쪽에 용량을 장하하여 설계ㆍ제작하였다. 설계된 안테나는 2.24GHz의 중심 주파수에서 S자형 변형된 MSA가 5.7%의 대역폭을 갖고, 용량을 장하한 변형된 MSA가 8.71%의 대역폭으로 용량을 장하한 변형된 MSA가 광대역 안테나임을 확인하였다. 또한 제작된 S자형 변형된 MSA의 방사 패턴 특성은 E면과 H면의 수직ㆍ수평 편파의 특성을 측정하여 비교하였다.

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Design of a Small Microstrip Antenna to load Capacitors (용량을 장하한 소형 마이크로스트립 안테나 설계)

  • Ko, Young-Hyuk;Sun, Seung-Ho
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.38 no.6
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    • pp.18-27
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    • 2001
  • In this paper, the MSA to load a capacitor without limitation of the electric force on the transformed MSA is proposed. Bandwidth of the proposed antenna is 7.76% at the resonant frequency of 1.9 GHz, is observed the resonant frequency and bandwidth versus change of any arbitrary feed point. It was found that the bandwidth of this MSA to load a capacitor is broader than that of the transformed MSA. Antenna,s equivalent circuit with transmission line model is designed to find more accurate resonant frequency and is calculated return loss value. The calculated value is agreed resonably with experimental value.

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Voice Tremor in Parkinsonism : A Preliminary Study for Differential Diagnosis (파킨슨증의 음성진전 : 감별진단을 위한 예비연구)

  • Choi, Seong-Hee;Kim, Hyang-Hee;Lee, Won-Yong;Choi, Hong-Shik
    • Speech Sciences
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    • v.12 no.3
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    • pp.19-33
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    • 2005
  • Tremor is a main factor of parkinsonism. Voice tremor may be the first, later or the only symptom of a neurological disease and its frequency, amplitude, and regularity may differ among the diseases of different neural subsystems. Differential diagnosis between idiopathic Parkinson's disease (IPD) and multiple system atrophy (MSA) has been difficult. This study included three groups: (1) 6 IPD patients; (2) 6 MSA patients; and (3) 20 ageand sex-matched normal controls. The MDVP (Multidimensional Voice Program) was used to analyze the sustained /a/phonation. The results were as follows: (1) frequency perturbation parameters (jitter, sPPQ, Vf0) and FTRI of tremor parameter of two patient groups were statistically different from those of the controls (p < .01); (2) measures were higher in short-term and long-term f0 and amplitude perturbation in MSA than IPD; (3) however, any acoustic parameters between IPD and MSA were not statistically different; except for the rate of frequency tremor, 4$\sim$5 Hz in IPD, 5$\sim$11 Hz in MSA and (4) the pattern of regularity for voice tremor through histogram indicated that amplitude of IPD was irregular while both f0 and amplitude of MSA were irregular. In conclusion, F0, rate of frequency tremor, and pattern of f0 regularity may be predictors for differential diagnosis. These findings might signify that voice tremor of parkinsonism was resulted from modulation of f0.

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Telematics Antenna for Vehicles (차량용 텔레매틱스 안테나)

  • 김해연;이병제;양성현
    • Journal of the Korea Computer Industry Society
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    • v.5 no.2
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    • pp.331-336
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    • 2004
  • In this paper, an antenna for telematics is proposed. It operates at GPS/GSM frequency-bands and it can be installed inside of a vehicle. There is a great difference between the proposed antenna and commonly used antennas. It needs not to use a dielectric with a high permittivity since it is formed on a sheet of FR4 with only 1mm thickness. Thus, it is possible to cut costs and make process of manufacture simple. Planar inverted-F antenna(PIFA) for GSM and microstrip antenna(MSA) for GPS is designed and PIFA-MSA antenna is proposed. The height is lower than that of commonly used antennas. And polarization of the PIFA and MSA is arranged perpendicularly for isolation improvement of each port, thus isolation of these two antennas is improved. Also, it is sufficient for the all specifications.

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Analysis of City Size Distribution and Spatial Structure - with Korean Metroplitan Statistical Areas (MSA) (한국 도시의 규모분포와 도시공간구조 분석 - 광역도시통계권을 중심으로)

  • Kim, Dong-Soo;Huh, Mun-Gu;Lee, Doo-Hee
    • Journal of the Economic Geographical Society of Korea
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    • v.11 no.4
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    • pp.549-563
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    • 2008
  • The purpose of this research is to identify the urban structure in Korea. Though there is research regarding urbanization, there is little regarding the urban structure of the Korean economy. In this paper, two issues will be discussed: the measurements of inter-city and intra-city structure in Korean Metropolitan Statistical Areas (MSAs), which is newly defined. First, the city size rank rule, widely known as Zipf’s Law, will illustrate Korean the inter-city structure. The city size rank rule gives an idea whether Korean MSAs are balanced or not. In general, Korea has a heavy concentration in the Seoul MSA in terms of population. It could be either that the Seoul MSA is too big or that the Busan MSA is too small or both. If this is the primacy problem, a decentralization policy is necessary. On the other hand, if it is a second city problem, development policies for the Busan MSA and Daegu MSA are more important. Next, the Korean intra-city structure will be discussed. The evolutions of the MSAs explain intra-city structure by analyzing population density function and the housing price function. Some large MSAs such as Seoul and Busan have experienced urban sprawl, while other MSAs have experienced urban concentration. The population density gradient by the distance from the ARC GIS shows the growth rate of a city. According to the Spatial Mismatch Index between population and employment, the Ulsan MSA, Gwangju MSA, and Suwon-Hwaseong-Osan MSA are more mismatched, while the Daejeon MSA and Incheon MSA are less mismatched. Therefore, these analyses of Korean urban structure are meaningful in developing regional policy.

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Characteristics of Partially Shorted MSA with a Slot (슬랏을 갖는 부분 단락 MSA의 특성)

  • 조창혁;박성교;박종백
    • Proceedings of the IEEK Conference
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    • 2000.11a
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    • pp.401-404
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    • 2000
  • We designed and fabricated partially shorted MSA with a slot for 850 MHz on Copper-clad Laminate substrate, where the width of the radiation patch is identical with that of the ground plane and one side of the radiation patch is partially shorted to the ground plane. The radiation patterns of ZX, XY and ZY planes were measured. As a result, a better co and cross polarization lot ZX plane was obtained, compared to the partially shorted MSA without a slot.

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A Study on the Absorption-Enhancing Effect of Sodium-5-methoxysalicylate (Sodium-5-Methoxy Salicylate의 흡수촉진 효과에 관한 연구)

  • 김기헌
    • YAKHAK HOEJI
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    • v.29 no.3
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    • pp.111-116
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    • 1985
  • Effect of sodium-5-methoxysalicyclate (5MSA-Na) on the absorption of cefmetazol (CMZ) was studied in rectum and duodenum of rats via in situ loop method. Effect of 5MSA-Na on the absorption of CMZ showed markedly different results in rectum and duodenu. Penetration of 5MSA-Na was greater in rectum than in duodenum and water-transfer was markedly increased in duodenum.

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