• Title/Summary/Keyword: Guard cell

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A Study on Compatibility between LTE and WLAN System for Mobile Satellite Wireless Package System

  • Ko, Hojeong;Jung, Soonho;Lee, Ilkyoo;Cho, Juphil;Cha, Jae Sang
    • International Journal of Internet, Broadcasting and Communication
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    • v.7 no.2
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    • pp.130-136
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    • 2015
  • In this paper, we analyzed the adjacent channel interference of the LTE band 40 defined by 3GPP on the WLAN system based on the Monte-Carlo method, and found the guard band required for compatibility between the two systems. This study have a difference compared to the previous studies about cell radius was determined using Extended Hata Model considering practical environment, interference protection distance related to guard band, and the spectrum emission mask improvement effect for minimizing the interference. Simulation results, for no channel interference compatibility of LTE and WLAN for mobile satellite wireless package system, we can find the need 15MHz guard band at specified spectrum emission mask and 10MHz guard band at assumed spectrum emission mask.

Performance Analysis of a Cellular Mobile Communication System with Hybrid Guard Channels (Hybrid 가드채널이 있는 이동통신시스템이 성능 평가)

  • Hong, Sung-Jo;Choi, Jin-Yeong
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.29 no.4
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    • pp.100-106
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    • 2006
  • We analyze a voice/data integrated traffic model of the cellular mobile communication system with hybrid guard channels for voice and handoff calls. In a multi-service integrated wireless environment, quality of service guarantee is crucial for smooth transportation of real time information. Real time voice traffic requires a guaranteed upper bounded on both delay and packet error rate, whereas data traffic does not. Voice traffic has high transmission priority over data packets. Thus one of the important problems is the design of admission control schemes which can efficiently accommodate the differential quality of service requirements. In this paper, a hybrid guard channel scheme is considered in which arriving calls are assigned channels as long as the number of busy channels in the cell is below a predetermined first threshold. When the number of busy channels reaches the first threshold, new originating data calls are queued in the infinite data buffer. Then reaches second threshold, only handoff calls are assigned the remaining channels and new originating voice calls are blocked. We evaluate the system by a two-dimensional Markov chain approach and generating function method and obtain performance measures included blocking probability and forced termination probability.

Cell Radius & Guard Band Requirements by Mutual Interference Investigation between Satellite Digital Systems using Gap-filler (Gap-filler를 이용하는 위성 DMB 시스템 간의 상호간섭분석에 의한 보호대역 및 적정 셀 반경 설정)

  • Cha Insuk;Park SungHo;Chang KyungHi;You Heung-Ryeol
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.6A
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    • pp.499-509
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    • 2005
  • The capacity of Satellite DMB(Digital Multimedia Broadcasting) system is limited mainly by the interference. So, to achieve the expected performance of Satellite DMB system and to minimize the interference from other Satellite DMB system, ACI(Adjacent Channel Interference) should be considered carefully. Satellite DMB system uses the Gap-filler for effective transmission in terrestrial environment, and the Gap-filler can use direct amplification or frequency conversion to satisfy the specific requirements. Therefore, amplified signal causes several effects on interference between System A(Eureka 147 DAB) and System E(ISDB : Integrated services Digital Broadcasting). In this paper, by using the outcome of system-level simulation considering the results of link-level simulation, we analyze the interferences between System A and System E under practical situation based on the exact parameters of ITU-R BO. 1130-4. We also propose the appropriate level of guard band and Cell Radius to optimize system capacity by adapting the spectrum mask given in the spec. and utilizing the interference analysis between System A and System E.

Effect of Nitrogen on Cell Dynamics at Leaf Growth Zone in Two Rice Varieties

  • Sung, Jwa-Kyung;Lee, Chul-Won;Kim, Tae-Wan;Hwang, Seon-Woong;Song, Beom-Heon
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.49 no.2
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    • pp.121-125
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    • 2004
  • In plants, nitrogen is the major component for growth and development. Leaf growth is based on the division, elongation and maturation of cells, which are used for making of epidermis, mesophyll, bundle sheath, xylem, phloem and so on. Dynamics of these tissues with respect to nitrogen are required for better understanding. This experiment was conducted to evaluate effect of nitrogen on the elongation of epidermal and guard cell of two rice (Oryza sativa L.) varieties, Seoanbyeo and Dasanbyeo on May 2000 at Chungbuk national university in Cheongju. After transplaning the 20-day-old seedlings into a/5000 pots, the main characteristics related with cell elongation were investigated and evaluated. A maximum. leaf length reached at 7 or 8 days after emerging from the collar, and also the leaf elongation rates were greatly affected by the increase of N application rate. The initial and final cell length were about $17\mu\textrm{m}$ and $130\mu\textrm{m}$, respectively. Cell divisions occurred within 1.0mm from leaf base. With die higher nitrogen application rate of 22 kg-N $10\textrm{a}^{-1}$, cell division per hour was greater 1.5 to 1.9 and 1.2 to 1.3 fold as compared to the N application rate of 0 and 11 kg-N $10\textrm{a}^{-1}$, respectively. Cell enlargement of epidermal and guard cell under higher N application rate (22kg-N $10\textrm{a}^{-1}$) was finished within about 20 (Seoanbyeo) and 15 hours (Dasanbyeo), while it took much time, about 30 hours.

Performance of call handling schemes for radio mobile exchange communication system applied by timeout Queue (무선 이동통신 교환시스템에서 타임아웃(timeout)큐를 적용한 호 처리 방식의 성능해석에 관한 연구)

  • 우상철;윤종호
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.2 no.1
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    • pp.59-70
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    • 1998
  • In the wireless mobile exchange communication system, the proper handling of originating call(OC) and handover call(HC) is important. Specially, when it's viewed from the user side, mobile users feel more weighting soul disappointment with the handover blocking probability moving from current cell to adacent cell than with originating call blocking probability happening new call in current cell. Accordingly,this paper is proposed and analyzed the timeout buffer system and guard channel for decreasing handover blocking probability. In analytic result, The more guard channel increase,t he more originating call blocking probability increase and handover blocking probability decrease. Also, the more timeout duration increase, the more handover blocking probability decrease.

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Epidermal Structure and Stomatal Types in Vegetative and Reproductive Organs of Three Species of Bryophyllum (Bryophyllum 3종의 영양기관과 생식기관에서 표피구조와 기공유형)

  • 정우규
    • Journal of Plant Biology
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    • v.30 no.1
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    • pp.43-57
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    • 1987
  • The epidermal structure and stomatal types in vegetative and reproductive organs of three species of Bryophyllum(B. crenatum, B. diagremontion, B. tubiflorum) were described. The epidermal cells were polygonal, isodiametric, and rectangular in the leaves and stems, and elongated cells in the stamens, styles, and ovaries. These cells were commonly thick, and arched or sinuous in the leaves, epiphylous bunds, petals and ovaries. They were straight in the stems, petioles, pedicels, and peduncles. In both vegetative and reproductive organs, the subsidiary cell walls were commonly thin and mostly arched in all the organs. The great majority of the mature stomata in all the organs were helicocytic type with a helix of four to six subsidiary cells. The mature stomata varied from organ to organ with regard to the number and arangement of subsidiary cells. The ontogenetic type of stomata in all the organs was mostly helico-eumesogenous type. This type was subdivided into three subtypes such as parahelico-eumesogenous, anomohelico-eumesogenous, and diahelico-eumesogenous stomata on the basis of the division angle fo the guard mother cell. Sometimes, the anisoeumesogenous type was found in various organs. This type was subdivided into three subtypes such as paraniso-eumesogenous, anomoaniso-eumesogenous, and dianisoeummesogenous stomata. The tetra-eumesogenous and duplotetra-eumesogenous types were rarely found; the former in the leaf of B. crenatum and the latter in the leaf of B. diagremontiana. Anomometric patterns in the mesogenous categorry of stomatal types was observed in a few organs of all the materials. A new stomatal type with tetra-eumesogenous stoma within a girdle of three subsidiary cells fo aniso-eumesogenous in the leaf of B. diagremontiana was firstly observed in the vascular plants. This stoma was termed the cotetra-aniso-eumesogenous type. Anormal stomata such as aborted stomata, single guard cells, stoma with a constricted part in the middle of large guard cells, and arrested stomata were found in the various organs of all the materials.

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An Automated Design of CMOS Standard Cells (CMOS 표준셀의 자동설계)

  • Kim, Han Heung;Kyung, Chong Min
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.23 no.6
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    • pp.988-994
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    • 1986
  • We present an automated CMOS standard cell design mehtodology which generates a mask description in the CIF (Caltech Intermediate Form)from a user-given logic description and design rule. The resultant layout reflects the user's choice among N-well, P-well and twin-well process and user's decision whether the guard band is to be included or not. Noise margin of each cell was improved by carefully adjusting the channel width of P-FET.

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Polyploidy and Acclimatization Rate of Broccoli Plane Derived from Anther Culture (葯培養 由來 녹색꽃양배추(Broccoli)의 幼植物 馴化 및 培數性 調査)

  • 이광식;박재복;안춘희;윤여중
    • Korean Journal of Plant Tissue Culture
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    • v.25 no.5
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    • pp.315-318
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    • 1998
  • This study was conducted to clarify the acclimatization rate and ploidy level of anther culture-derived plants in broccoli. The acclimatization rate from 71.4 to 100% was obtained from 7 varieties in 2 years. It was possible to identify the ploidy of the Plants obtained through anther culture by measuring the number of chloroplast in the guard cell. The average numbers of chloroplasts per guard cell in haploid diploid, and tetraploid were 8.5, 13.5 and 18.5, respectively. The regenerated plants could be classified based on these results into 47.1-51.3% of haploids, 47.9∼51.7%, diploid, and 0.8∼l.2% of tetraploids.

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CHARACTERISTIC ANALYSIS FOR GUARD LAMP USING SOLAR CELL (솔라셀을 적용한 보안등의 특성 분석에 관한 연구)

  • Kang, Byung-Bog;Ji, Woon-Seok;Lim, Jung-Yeol;Yu, Chang-Woo;Kim, Seok-Jong;Cha, In-Su
    • Proceedings of the KIEE Conference
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    • 2004.04a
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    • pp.196-200
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    • 2004
  • A guard lamp system has been installed at the PV positive center, located at Gwangju in Korea. Digital environment that is represented to internet is displacing business way of industry and business achievement way with the fast speed being giving great change on life whole, improve existence business process utilizing internet and Web connection technology, information superhighway to tradition industrialist manufacture and e-transformation's propulsion that wish to maximize productivity and administration efficiency is spread vigorously. In this paper, we wish to accomplish generation equipment's heighten stability and believability through remote monitoring and control of guard lamp system. This paper describes the design of the monitoring system for the sensing data and indirect controlling of the guard lamp system. Most of the conventional monitoring systems depend on the special hardware and software. The essential design of monitoring system is to provide the convenience for the user and the portability for the system. In order for the system to fulfill its requirements, it was designed using Labview GUI facility based on the Windows 2000 environment of IBM PC compatible and Add-on card based on the TCP/IP protocol. Advantage of the monitoring system are a personnel expenses curtailment effect, of the place restriction and unmanned system of the generation plants, etc..

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THE CHARACTERISTIC OF SOLAR CELL FOR GUARD LAMP (보안등에 적용하기 위한 태양전지의 특성 분석)

  • Kang Byung-Bog;Ji Woon-Seok;Lim Jung-Yeol;Kim Seok-Jong;Yu Chang-Woo;Cha In-Su
    • Proceedings of the KIEE Conference
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    • summer
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    • pp.1489-1491
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    • 2004
  • A guard lamp system has been installed at the PV positive center, located at Gwangju in Korea. Digital environment that is represented to internet is displacing business way of industry and business achievement way with the fast speed being giving great change on life whole, improve existence business process utilizing internet and Web connection technology, information superhighway to tradition industrialist manufacture and e-transformation's propulsion that wish to maximize productivity and administration efficiency is spread vigorously. In this paper, we wish to accomplish generation equipment's heighten stability and believability through remote monitoring and control of guard lamp system. This paper describes the design of the monitoring system for the sensing data and indirect controlling of the guard lamp system. Most of the conventional monitoring systems depend on the special hardware and software. The essential design of monitoring system is to provide the convenience for the user and the portability for the system. In order for the system to fulfill its requirements, it was designed using Labview GUI facility based on the Windows 2000 environment of IBM PC compatible and Add-oncard based on the TCP/IP Protocol. Advantage of the monitoring system are a personnel expenses curtailment effect, of the place restriction and unmanned system of the generationplants, etc..

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