• Title/Summary/Keyword: transmission rate

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Call admission scheme for low speed multimedia services in CDMA mobile communication systems (CDMA 이동통신시스템에서의 저속 멀티미디어 서비스를 위한 호 수락 방식)

  • 최경수;권수근;전형구;유영갑
    • Journal of the Korean Institute of Telematics and Electronics S
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    • v.35S no.7
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    • pp.14-21
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    • 1998
  • In providing with low speed multimedia services, a call blocking rate is greatly varied according to the transmission rate, and thereofr, the call blocking rate is remarkably increased for a service having a high transmission rate compared to a service having a low transmission rate. This paper presents three methods of solving this problem; Packing Scheme in which available channels distributed to each frequency channel are concentrated on one frequency channel and a call having a high transmission rate is assigned to the frequency channel; Queuing Scheme in which queuing is assigned to calls under service is temporarily reduced and a call having a high transmission rate is allowed. The result of performance analysis for 13 Kbps and 128 Kbps service through computer simulation showed that the call blocking rate for 128 Kbpx service was reduced by tens of percent accoring to loads.

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An Efficient Transmission Plan for Adaptable Bandwidth Allocation Technique (적응형 대역폭 할당 방법을 위한 효율적인 전송 계획)

  • Lee, Myoun-Jae;Park, Do-Soon
    • The KIPS Transactions:PartC
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    • v.14C no.3 s.113
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    • pp.285-292
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    • 2007
  • In the adaptable bandwidth allocation technique, a transmission plan for variable rate video data is made by the CBA algorithm and the data is transmitted by considering network traffic. But the CBA algorithm produces a transmission plan where the size of the increasing interval of transmission rate is generally larger than the size of the decreasing interval. And the transmission rate in CBA algorithm is changed in overflow curve during the increasing interval of transmission rate. This ぉy cause many frames to be discarded when available transmission rate is small. In this paper, a smoothing algorithm is proposed, where transmission rate is changed in the middle of underflow curve and overflow curve, but the transmission rate increases at the minimum. In order to show the performance, the proposed algorithm and a CBA algorithm were applied to a transmission plan in the adaptable bandwidth allocation technique, and the minimum frame rates, the average frame rates, the variation of frame rates, and the numbers of discarded frames were compared in both algorithms.

A Genetic Approach to Transmission Rate and Power Control for Cellular Mobile Network (ICEIC'04)

  • Lee YoungDae;Park SangBong
    • Proceedings of the IEEK Conference
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    • summer
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    • pp.10-14
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    • 2004
  • When providing flexible data transmission for future CDMA(Code Division Multiple Access) cellular networks, problems arise in two aspects: transmission rate. This paper has proposed an approach to maximize the cellular network capacity by combining the genetic transmission rate allocation and a rapid power control algorithm. We present a genetic chromosome representation to express call drop numbers and transmission rate to control mobile's transmission power levels while handling their flexible transmission rates. We suggest a rapid power control algorithm, which is based on optimal control theory and Steffenson acceleration technique comparing with the existing algorithms. Computer simulation results showed effectiveness and efficiency of the proposed algorithm Conclusively, our proposed scheme showed high potential for increasing the cellular network capacity and it can be the fundamental basis of future research.

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ANALYSIS OF OPTICAL TRANSMISSION CHARATERISTICS BY VISIBLE LIGHT INTO SHADE GHIDES (가시광선영역에서 shade guide에 따른 광투과도 특성 연구)

  • Choi, Keun-Bae;Park, Charn-Woon;Song, Chang-Yong;Ko, Sok-Min
    • The Journal of Korean Academy of Prosthodontics
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    • v.38 no.2
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    • pp.147-159
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    • 2000
  • The purpose of this study was the evaluation of spectral transmission of the commercial three shade guides and the relationship of hue, value, and chroma according to the transmission rate. The spectral transmittance of three shade guides - Vita Lumin Shade Guide, Vintage and Unibond Shade Guide, and Vitapan 3D-Master Shade Guide - were measured. For direct transmission measurements, each shade tabs were placed at the entrance port of the 1mm diameter intergrating sphere. The intensity of the light source passing through the shade tabs to the right angle was continuously recorded for wavelength from 400 to 700 nm. A transmission spectrum and digital data were obtained for each measurement and they were evaluated using Microcal Origin program. The obtained results of this study were as follows : 1. In Vita Lumin Shade Guide, sum of the transmission rate of the shade tabs at the wavelength 400-700nm was decreased in agreement with the arrangement order at each A, B, C, D group, except D4 shade tab. However, there were no relationships between the transmission rate of the shade tabs and the value-oriented. 2. In Vintage and Unibond Shade Guide, sum of the total transmission rate of the shade tabs was decreased in agreement with the arrangement order at each A, B, C, B group. When all shade tabs arranged in value-oriented, transmission rate was accord with the order, except D4 shade tab. 3. When shade tabs of the Vitapan 3D-Master Shade Guide have the same value and hue, sum of their total transmission rate decreased in accordance with the chroma-oriented. When the shade tabs have the same value and chroma, there were no differences from the order of the transmission rate to the various hue type. However, in the 'R' tabs of reddish hue type, the transmission rate increased at the long wavelength range area. In conclusion, we need the quantitative analyzing instruments in transmission determination. Vitapan 3D-Master Shade Guide covers the tooth color space taking into account the parameters of the systematic value, chroma, hue oriented, and the transmission rate relatively accorded with that sequence.

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Analysis on the Decision of Transmission Cost Allocation Rate Using the Arbitration Game (중재계임을 이용한 송전비용배분비율 결정에 관한 분석)

  • Chung, Koo-Hyung;Yoo, Chong-Il;Kang, Dong-Joo;Han, Seok-Man;Kim, Bal-Ho
    • Proceedings of the KIEE Conference
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    • 2002.11b
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    • pp.375-377
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    • 2002
  • In many parts of the world. the electricity industry is undergoing unprecedented changes. Hence, in order to reform the electricity industry readily and efficiently and minimize the confusion by these restructuring, it is required the systematic studies related to transmission pricing and transmission cost allocation issues. However, even now the basis of transmission cost allocation rate is not equipped so that the regulation body has determined the allocating rate under the common practice. In this paper it is demonstrated that the decision of transmission cost allocation rate is the regulation body's own right. For the analysis, game theory is applied to the procedure determining this rate and the competition to determine this rate between generators and distributors is modeled as the arbitration game.

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Performance Evaluation focused on Burst of Smoothing Algorithms (스무딩 알고리즘들의 버스트 성능 평가)

  • Lee, Myoun-Jae
    • Journal of Digital Contents Society
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    • v.13 no.1
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    • pp.111-118
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    • 2012
  • The burst is to require abruptly high transmission rate in case of transmitting pre-stored variable bit rate video data, and it causes to be inefficient use of network resource, resource reservation. To avoid these problems, smoothing is transmission plan where variable rate video data is converted to a constant bit rate stream. These smoothing algorithms include CBA, MCBA, MVBA and others. To evaluate amount of burst reduction in the existing CBA, MCBA, MVBA algorithm, this paper compares the burst-related-factors of transmission plan in smoothing algorithms with original video sources which were stored Variable Bit Rate. There are maximum frame bytes, maximum GOP bytes, transmission rate variability per frame, transmission rate variability per GOP in burst-related evaluation factors. Experimental result shows burst-related factors of smoothing algorithms which were used for experiment lower than that of pre-stored video data, except special case.

Efficient Delivery of Multimedia Traffic Using Muti-rate Transmission of 802.11e HCCA MAC Protocol (IEEE 802.11e HCCA MAC의 다중 전송률을 이용한 멀티미디어 트래픽의 효율적 전송)

  • Kim, Young-Hwan;Suk, Jung-Bong
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.33 no.4B
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    • pp.192-198
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    • 2008
  • In this paper, we propose a scheme that improves the transmission performance of realtime multimedia data in wireless Local Area Network (LAN) environment, through the dynamical control of Transmission Opportunity (TXOP) period of the IEEE 802.11e HCCA Medium Access Control (MAC). The existing schedulers which determine the frame transmission time and its duration could not appropriately cope with the change of physical transmission rate, since the TXOP period has remained unchanged with the change of transmission rate of the wireless station. Our scheme is devised to keep the transmission performance of real-time multimedia data effectively unchanged by making TXOP period be extended when the transmission rate gets reduced. The proposed scheme is experimented along with IEEE 802.11e reference model using NCTUns simulator, which shows that the multimedia data is effectively delivered with the change of transmission rate as the distance between the wireless station and its access point increases.

A Comparative Study of the Diachronic Change in the Transmission Rate of Broadcast Messages (방송 메시지 전달 속도의 통시적 비교에 관한 연구: 라디오뉴스 전달 속도 분석을 중심으로)

  • Park, Kyung-Hee
    • MALSORI
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    • no.64
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    • pp.15-37
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    • 2007
  • The purpose of this paper is to examine the change of the times on the transmission rate of broadcast message. In order to find out the research results, I collected past recorded news tapes and selected 22 radio news out from era of Japanese Imperialism, 1950's, 1960's and contemporary age. Next I measured each announcer's reading rate, and compared change on news-reading rate between present and past approximately 50 years ago. The results of study with such procedures and methods are as follows : the average reporting rate of newscasters in each era is different. From these results, we can easily grasp diachronic change in the transmission rate of broadcast message. Namely, the results show us that present announcers read news faster than the group of past era of Japanese Imperialism by 68%.

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A Study on the Flow Characteristic of Lubrication Oil System in Manual Transmission System for Large Commercial Vehicle (대형 상용차용 수동변속기내 윤활시스템의 유동특성에 관한 연구)

  • Yi, Chung-Seob;Suh, Jeong-Se;Song, Chul-Ki;Shin, Yoo-In;Yun, Ji-Hun;Chung, Kyung-Taek
    • The KSFM Journal of Fluid Machinery
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    • v.13 no.6
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    • pp.77-82
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    • 2010
  • This study has conducted numerical analysis for lubrication system of transmission for commercial vehicle. The lubrication oil system in transmission can be applied to a large scale commercial vehicle which is over 15tons. The flow rate of lubricating oil has been obtained for each of branch port from the lubrication pipe. The results from numerical simulation are mainly suggested for the mass flow rate of lubrication oil in the rotating main shaft of transmission system. It has been found that the mass flow rate from oil hole increased with an rotating rate of main shaft. The flow characteristic from oil hole has been presented for the lubricating system in the manual transmission.

Seed Transmission of Chrysanthemum stunt viroid in Chrysanthemum

  • Chung, Bong-Nam;Pak, Ha-Seung
    • The Plant Pathology Journal
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    • v.24 no.1
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    • pp.31-35
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    • 2008
  • The presence of Chrysanthemum stunt viroid (CSVd) in seed and pollen of diseased chrysanthemum was demonstrated. In seeds infected male parent from crosses in May, CSVd was transmitted to 6.7% of the progeny seedlings, whereas if the female parent was infected, CSVd transmission rate was between 46.9 and 75.7%. A relatively high incidence of 94.4 to 96.0% seed transmission occurred when both parents were infected. In seeds infected male parent from crosses in December, no progeny seedlings were infected with CSVd, whereas if the female parent did, CSVd transmission rate was 1.5%. When both parents were infected, 6.9% seed transmission was occurred. The seed transmission rate depended on the temperature when the crosses were made. CSVd was not detected in the non-infected female parent pollinated with infected pollen but was transmitted to the progenies. This is the first report of seed-borne transmission of CSVd in chrysanthemum.