• Title/Summary/Keyword: CLR

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A Study on the CLR Performance Improvement for VBR Traffic in the Wireless ATM Access Network (무선 ATM 가입자망에서 VBR 트래픽의 CLR 성능개선)

  • 이하철
    • Journal of Korea Multimedia Society
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    • v.7 no.5
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    • pp.713-720
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    • 2004
  • In this paper we suggest error control scheme to improve CLR performance degradation on wireless ATM access networks which consist of access node and wireless channel. Based on the cell scale and hurst scale, traffic model of wireless ATM access network is analyzed. The CLR equation due to buffer overflow for wireless access node is derived for VBR traffic. the CLR equation due to random bit errors and burst errors for wireless channel is derived. Using the CLR equation for both access node and wireless channel, the CLR equation of wireless ATM access network is derived, and we evaluate the CLR performance on the wireless ATM access networks with conventional SR ARQ scheme and recommended error control scheme, that is, Type I Hybrid ARQ scheme. It is confirmed that CLR performance of the access networks with recommended error control schemes is superior to that of access networks with conventional error control scheme.

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A Study on the Relation of CLR and Blocking Probaility for ATM Traffic in the Wireless ATM Access Network (무선ATM 접속망에서 ATM 트래픽의 CLR과 호손율 성능분석)

  • 이하철;이병섭
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.25 no.7B
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    • pp.1167-1177
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    • 2000
  • 본 논문에서는 접속노드와 무선채널로 구성되는 무선 ATM(Asynchronous Transfer Mode) 접속망의 셀 손실율과 호손율간의 관계를 도출하였다. 이를 위해 우선 ATM 접속망의 트래픽 모델을 셀 레벨, 버스트셀 레벨 및 호접속레벨로 구부하여 분석하였고, 무선접속노드의 CLR(Cell Loss RAtio) 성능을 나타낼 수 있는 수식을 VBR(Variable Bit Rate) 및 램덤 트래픽으로 구분하여 제시하였으며 무선채널에 대해서는 랜덤에러 및 버스트 에러환경으로 구분하여 CLR 성능을 나타낼 수 있는 수식을 유도하였다. 그리고 접속노드와 무선채널의 CLR을 나타내는 수식을 이용하여 무선 ATM 접속망의 CLR 성능을 나타내는 수식을 도출한 후 접속망의 트래픽 성능평가를 위해 VBR, CBR 및 랜덤 트래픽 형태별로 CLR과 호손율간의 관계를 분석하였다. 즉 이용도와 CLR간의 관계로부터 셀 레벨의 접속망 CLR 목표치가 정해지면 이용도 및 접속 회선수를 구할 수 있으며 이를 호 접속레벨의 Erlang-B 관계식과 관련시켜서 CLR과 호손율간의 관계를 제시하였다.

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The Relation of CLR and Blocking Probability for CBR Traffic in the Wireless ATM Access Network

  • Lee, Ha-Cheol;Lee, Byung-Seub
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.27 no.11C
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    • pp.1158-1163
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    • 2002
  • In this paper it is focused on the relation between CLR (Cell Loss Ratio) and blocking probability, GoS(Grade of Services) parameters in the wireless ATM (Asynchronous Transfer Mode) access network which consists of access node and wireless channel. Traffic model of wireless ATM access network is based on the cell scale, burst scale and call connection level. The CLR equation due to buffer overflow for wireless access node is derived for CBR (Constant Bit Rate) traffic. The CLR equation due to random bit errors and burst errors for wireless channel is derived. Using the CLR equation for both access node and wireless channel, the CLR equation of wireless ATM access network is derived. The relation between access network CLR and blocking probability is analyzed for CBR traffic.

The Relation of Cell Scale and Call Connection Level for the VBR Trafac in the Wireless ATM Access Transport (무선 ATM 액세스 전달구조에서 VBR 트래픽에 대한 셀 스케일과 호 접속레벨간의 관계)

  • Lee Ha-Cheol
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.9B
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    • pp.596-601
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    • 2005
  • In this paper it is focused on the relation between CLR(Cell Loss Ratio) and blocking probability in the wireless ATM access transport. Traffic model of wireless ATH access transport is based on the cell scale, burst scale and call connection level. The CLR due to buffer overflow for wireless access node is derived for VBR traffic. The CLR due to transmission errors for wireless channel is derived. Using the CLR for both access node and wireless channel: the CLR of wireless ATM access transport is derived. The relation between CLR and blocking probability is analyzed for VBR traffic to evaluate performance of wireless ATM access transport.

Metabolisable Energy, In situ Rumen Degradation and In vitro Fermentation Characteristics of Linted Cottonseed Hulls, Delinted Cottonseed Hulls and Cottonseed Linter Residue

  • Bo, Y.K.;Yang, H.J.;Wang, W.X.;Liu, H.;Wang, G.Q.;Yu, X.
    • Asian-Australasian Journal of Animal Sciences
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    • v.25 no.2
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    • pp.240-247
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    • 2012
  • Dietary supplementation with conventional linted cottonseed hulls (LCSH) is a common practice in livestock production all over the world. However, supplementation with mechanically delinted cottonseed hulls (DCSH) and cottonseed linter residue (CLR) is uncommon. Cottonseed by-products, including LCSH, DCSH and CLR, were assessed by chemical analysis, an in situ nylon bag technique, an in vitro cumulative gas production technique and in vitro enzyme procedure. The crude protein (CP) content of CLR (302 g/kg dry matter (DM)) was approximately 3 times that of LCSH and 5 times that of DCSH. The crude fat content was approximately 3 times higher in CLR (269 g/kg DM) than in LCSH and 4 times higher than in DCSH. Neutral detergent fibre (311 g/kg DM) and acid detergent fibre (243 g/kg DM) contents of CLR were less than half those of DCSH or LCSH. Metabolisable energy, estimated by in vitro gas production and chemical analyses, ranked as follows: CLR (12.69 kJ/kg DM)>LCSH (7.32 kJ/kg DM)>DCSH (5.82 kJ/kg DM). The in situ degradation trial showed that the highest values of effective degradability of DM and CP were obtained for CLR (p<0.05). The in vitro disappearance of ruminal DM ranked as follows: CLR>LCSH>DCSH (p<0.05). The lowest digestibility was observed for DCSH with a two-step in vitro digestion procedure (p<0.05). The potential gas production in the batch cultures did not differ for any of the three cottonseed by-product feeds. The highest concentration of total volatile fatty acids was observed in CLR after a 72 h incubation (p<0.05). The molar portions of methane were similar between all three treatments, with an average gas production of 22% (molar). The CLR contained a higher level of CP than did LCSH and DCSH, and CLR fermentation produced more propionate. The DCSH and LCSH had more NDF and ADF, which fermented into greater amounts of acetate.

QoS of MPEG-2 Video under Cell Loss Condition (셀손실에 따른 MPEG-2 비디오의 서비스 품질)

  • Han, Jong-Seok;Choi, Jae-Hyoung;Kim, Jee-Joong
    • Journal of the Korean Institute of Telematics and Electronics S
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    • v.36S no.8
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    • pp.30-38
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    • 1999
  • On providing MPEG-2 video service through the ATM network, it is necessary for network provider to have the ATM QoS objectives in order to guarantee quality of service required by end users at the application layer. In this paper, the degradation of QoS caused by cell losses at application layer is assessed quantitatively by GIQ model considering AAL layer and is evaluated qualitatively by MOS from the viewpoint of the end users in order to analyze the relation between CLR and QoS of MPEG-2 video. From the simulation and empirical results, we know that CLR and $GIQ_{mean}$ for guaranteeing QoS of MOS grade 5(Excellent) are $CLR{\le}4{\times}10^7$ & $GIQ_{mean}{\ge}99.4%$ and those for guaranteeing QoS of MOS grade 4(Good) are $CLR{\le}2{\times}10^6$ & $GIQ_{mean}{\ge}99.705%$.

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Effects of Curcuma longa Rhizoma on Asthma induced intra-nasal instillation of Ovalbumin in Mice (강황이 난황의 비강내 점적을 통하여 유발된 생쥐의 천식에 미치는 영향)

  • Lee, Jun-Hun;Kim, Jong-Han;Park, Su-Yeon;Choi, Jeong-Hwa
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.21 no.3
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    • pp.20-35
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    • 2008
  • Objective : This study was designed to investigate the effects of Curcuma longa Rhizoma(CLR) on asthma. Methods : Detecting splenocyte proliferation rates, cytokines and antigen specific antibody isotypes in bronchoalveolar lavage fluid (BALF). In addition, the present author I also investigated changes in spleen and histopathological changes of lung tissues. Results : Oral administration of CLR lowered spleen weight and splenocyte proliferation rates. In addition, levels of IL-4, IL-17A and Granulocyte/Macrophage Colony-Stimulating Factor(GM-CSF), Th2 driven cytokines, were lowered respectively and IFN-g, and Th1 driven cytokine, were elevated by CLR. Levels of Ovalbumin(OVA) specific IgE and IgGl in BALF were also lowered by oral administration of CLR too. Conclusion : CLR is useful to treat patients with asthma and the mechanisms are related to the in suppression of Th2 skewing reactions.

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Analysis on magnetizing characteristics of current limiting reactor using HTSC module

  • Han, Tae Hee;Lim, Sung Hun
    • Progress in Superconductivity and Cryogenics
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    • v.20 no.1
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    • pp.15-18
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    • 2018
  • In this paper, the magnetizing characteristics of the current limiting reactor (CLR) using $high-T_C$ superconducting (HTSC) module were analyzed. Since the saturation of iron core comprising the CLR using HTSC module deteriorates its current limiting operation, the design of the CLR using HTSC module considering the magnetizing characteristics is needed. For the analysis on the magnetizing characteristics, the flux linkage and the magnetizing current of this CLR using HTSC module were derived from its electrical equivalent circuit. Through the analysis on the linkage flux versus the magnetizing current, obtained from the short-circuit tests, the suppressing effect of the iron core's saturation was discussed.

Analysis on the Protective Coordination with Hybrid Superconducting Fault Current Limiter (저항접지 시스템에서 지락사고시 CLR과열 소손방지를 위한 GPT 정격용량의 적정성 연구)

  • Shin, Ho-Jeon;Kim, Jin-Seok;Park, Yu-Hwan;Kim, Jae-Chul;Cho, Man-Young
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.61 no.4
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    • pp.503-508
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    • 2012
  • Among the high distribution voltage consumers, high-capacity consumers are often applying the grounding resistance method in order to overcome demerits such as erroneous operation of the ground reply or potential increase in the battery at the accident of the isolated neutral system. In this paper, to prevent damage to CLR and GPT in the delay to block the breakdown in the resistance grounded neutral system, this study aims to provide a proper suggestion for continuous rating capacity of GPT to check the appropriateness of CLR size and reduce GPT burden. Thereupon, this study comparatively analyzes CLR current applied in general GPT and the current gained when CLR demanded in the system is used and analyzes the simulated system through simulation using PSCAD/EMTDC in order to suggest GPT's proper continuous rating capacity.

Dynamic Cell Leveling to Support Location Based Queries in R-trees (R-tree에서 위치 기반 질의를 지원하기 위한 동적 셀 레벨링)

  • Jung, Yun-Wook;Ku, Kyong-I;Kim, Yoo-Sung
    • Journal of Korea Spatial Information System Society
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    • v.6 no.2 s.12
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    • pp.23-37
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    • 2004
  • Location Based Services(LBSs) in mobile environments become very popular recently. For efficient LBSs, spatial database management systems must need a spatial indexing scheme such as R-trees in order to manage the huge spatial database. However, it may need unnecessary disk accesses since it needs to access objects which are not actually concerned to user's location-based queries. In this paper, to support the location-based queries efficiently, we propose a CLR-tree(Cell Leveling R-tree) in which a dynamic cell is built up within the minimum bounding rectangle of R-trees' node. The cell level of nodes is compared with the query's cell level in location-based query processing and determines the minimum search space. Also, we propose the insertion, split, deletion, and search algorithms for CRL-trees. From the experimental results, we see that a CLR-tree is able to decrease $5{\sim}20%$ of disk accesses from those of R-trees. So, a CLR-tree can be used for fast accessing spatial objects to user's location-based queries in LBSs.

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