• Title, Summary, Keyword: Rate Control

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Comparisons of Control Charts for Failure Rate with Fixed Inspection Interval

  • Lee, Jae-Man;Chang, Duk-Joon
    • Journal of the Korean Data and Information Science Society
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    • v.15 no.4
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    • pp.793-801
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    • 2004
  • In this paper, we propose control charts for failure rate using the number of failures based on the fixed interval inspection with replacement. And we investigate the power of detection of the proposed control charts by the ARL.

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Nationwide Reduction of Primary Energy and Greenhouse Gas Emission by PMV Control Considering Individual Metabolic Rate Variations in Apartments (아파트 건물에서 재실자 활동량이 고려된 PMV제어에 따른 연간 국가 차원의 1차 에너지 및 온실가스 감축량 분석)

  • Hong, Sung-Hyup;Do, Sung-Lok;Lee, Kwang Ho
    • Journal of the Architectural Institute of Korea Structure & Construction
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    • v.34 no.10
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    • pp.37-44
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    • 2018
  • In this study, the effects of considering hourly metabolic rate variations for predicted mean vote (PMV) control on the heating and cooling energy and greenhouse gas emission were investigated. The case adopting PMV control taking the hourly metabolic rate into account was comparatively analyzed against the conventional dry-bulb air temperature control, using a detailed simulation technique. Under the assumption that all the apartments in Korea adopt the PMV control incorporating real-time metabolic rate measurements, nationwide reductions of primary energy and greenhouse gas emission were analyzed. As a result, PMV control considering hourly metabolic rate variations is expected to reduce national primary energy by 6.2% compared to conventional dry-bulb air temperature control, corresponding to reduction of 10,342 GWh. In addition, it turned out that 6.6% of tCO2 emission can be reduced by adopting PMV control, corresponding to nationwide reduction of greenhouse gas emission by approximately 1,720,000 tCO2.

Video Rate Control Using Activity Based Rate Prediction

  • Park, Hyung-Shin;Jung, You-Young;Kim, Young-Ro;Ko, Sung-Jea
    • Proceedings of the IEEK Conference
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    • pp.454-457
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    • 2000
  • In this paper, an efficient rate control algorithm based on rate prediction is proposed for maintaining a smooth buffer variation and a small buffer size. The proposed method adjusts the quantization scaling factor by using the predicted bit-rate to meet the target bit budget exactly. Experimental result show that the proposed prediction-based rate control scheme can regulate the bit-rate across scene changes more effectively and achieve better PSNR performance than existing rate control mechanisms such as the MPEG-2 Test Model 5 (TM5) and the Adaptive Scene Analysis (ASA).

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A Cost-Effective Rate Control for Streaming Video for Wireless Portable Devices

  • Hong, Youn-Sik;Park, Hee-Min
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.5 no.6
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    • pp.1147-1165
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    • 2011
  • We present a simple and cost effective rate control scheme for streaming video over a wireless channel by using the information of mobile devices' buffer level. To prevent buffer fullness and emptiness at receivers, the server should be able to adjust sending rate according to receivers' buffer status. We propose methods to adjust sending rate based on the buffer level and discrete derivative of the buffer occupancy. To be compatible with existing network protocols, we provide methods to adjust sending rate by changing the inter-packet delay (IPD) at the server side. At every round-trip time, adjustments of sending rate are made in order to achieve responsiveness to sudden changes of buffer availabilities. A series of simulations and the prototype system showed that the proposed methods did not cause buffer overflows and it can maintain smoother rate control and react to bandwidth changes promptly.

A Study on Multirate Control Using a Current Estimator (현재 상태 추정기를 이용한 멀티레이트 제어에 관한 연구)

  • 황희철;정정주;정동실
    • Journal of Institute of Control, Robotics and Systems
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    • v.8 no.12
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    • pp.1004-1013
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    • 2002
  • A multirate state feedback control (MRSFC) method is proposed for systems sensitive to disturbance and noise based on the multirate estimator design using current estimator. MRSFC updates the controller output slower than the measurement sampling fiequency of system output by a lifting factor $R=T_c/T_s$ The closed-loop MRSFC system is less sensitive to disturbance and noise due to filtering effect than the conventional single-rate control system The multirate estimator gain can be obtained by solving a conventional pole placement problem such that MRSFC has the same spectrum of eigenvalues in the s-plane as the single-rate control. We applied the proposed multirate state feedback controller to a galvanometer servo system Simulation and experimental results show that settling and tracking performances are improved compared with a conventional single-rate pole placement control (PPC).

Adaptive rate control scheme for very low bit rate video coding (초고속 전송 매체용 비디오 코딩을 위한 적응적 비트율 제어에 관한 연구)

  • 오황석;이흥규;전준현
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.21 no.5
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    • pp.1132-1140
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    • 1996
  • In video coding systems, an effective rate control method is one of the most improtant issues for the good video quality. This paper presents an adaptive rate control scheme based on the buffer fullness, quantization, and buffer utilization for very low bit rate communication lines, such as 16kbit/s, 24bit/s, and so on. The strategy is implemented on H.263, whichis a vide coding algorithm for narrow band telecommunication channels up to 64kbit/s recommended by ITU-T SG15, to show the effectiveness. The simulation result shows that the suggested rate control scheme has better SNR performance and buffer utilization of source coder than those of linear and non-linear[9] buffer control strategies.

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A New Approach to Solve the Rate Control Problem in Wired-cum-Wireless Networks

  • Loi Le Cong;Hwang Won-Joo
    • Journal of Korea Multimedia Society
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    • v.9 no.12
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    • pp.1636-1648
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    • 2006
  • In this paper, we propose a new optimization approach to the rate control problem in a wired-cum-wireless network. A primal-dual interior-point(PDIP) algorithm is used to find the solution of the rate optimization problem. We show a comparison between the dual-based(DB) algorithm and PDIP algorithm for solving the rate control problem in the wired-cum-wireless network. The PDIP algorithm performs much better than the DB algorithm. The PDIP can be considered as an attractive method to solve the rate control problem in network. We also present a numerical example and simulation to illustrate our conclusions.

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An Adaptive UDT Rate Control Method on Network Traffic Condition (네트워크 트래픽 상태에 적응적인 UDT Rate Control 기법)

  • An, Do-Sik;Wang, Gi-Cheol;Kim, Seung-Hae;Cho, Gi-Hwan
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.48 no.3
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    • pp.19-27
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    • 2011
  • Due to the growth of optical fiber network technologies, most networks recently support several tens of Gb/s bandwidth. UDT(UDP-based Data Transfer protocol) is an optimized protocol for bulk data transmission on the network, which has the high bandwidth and long delay time. It periodically controls the sending rate on the fixed sync-interval, 0.01 sec. Here, if the network traffic status varies quickly, available network bandwidth is not able to be properly utilized in-between the sync-intervals. In this paper, we propose an adaptive rate control method with considering the network traffic status in-between the sync-interval periods. The network traffic status is determined based on the RTT variances. With dividing the network status into four classes, the proposed method performs a new rate control by adjusting the inter-packet sending period for a corresponding class. As a simulation result, the proposed method improves the message delivery throughput as well as stability than that of the existing UDT Protocol.

Reliable Message Routing Protocol for Periodic Messages on Wireless Sensor Networks (무선센서 네트워크에서 주기적 메시지에 대해 신뢰성 있는 메시지 전송을 위한 라우팅 프로토콜)

  • Ngo, Hoai Phong;Kim, Myung-Kyun
    • Journal of Institute of Control, Robotics and Systems
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    • v.17 no.2
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    • pp.190-197
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    • 2011
  • In industrial distributed control systems, sensors collect data from the physical environment periodically and transmit them to the actuators, which process the control operations based on the received data. For the effective operation of the control systems, the data transmitted by the sensors has to be delivered to the actuators reliably within the deadline, and if the message reception rate of the actuators becomes lower than a threshold, then the performance of the control systems drops greatly. This paper suggests a message routing protocol to transmit periodic messages reliably in a distributed control system based on wireless sensor networks. For reliable message transmission, the proposed protocol selects a routing path whose end-to-end message reception rate is the highest before transmitting data messages. The proposed protocol has the capability of maintaining a target message reception rate for each flow. To maintain the required target reception rate, each destination monitors the actual message reception rate periodically and transmits a feedback message to the source if it drops below the target reception rate. On receiving the feedback message, the source tries to find a new path which can satisfy the target rate. The performance of the proposed protocol has been evaluated using simulation and compared with other protocols in terms of the message reception rate, the message delay and delay jitter, and so on. The simulation results show that the proposed protocol has a higher message reception rate and comparable message delay and delay jitter to other protocols. The simulation results also show that the proposed protocol has an ability to adapt well to the dynamic network traffic change.

Novel Rate Control Scheme for Low Delay Video Coding of HEVC

  • Wu, Wei;Liu, Jiong;Feng, Lei
    • ETRI Journal
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    • v.38 no.1
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    • pp.185-194
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    • 2016
  • In this paper, a novel rate control scheme for low delay video coding of High Efficiency Video Coding (HEVC) is proposed. The proposed scheme is developed by considering a new temporal prediction structure of HEVC. In the proposed scheme, the relationship between bit rate and quantization step is exploited firstly to formulate an accurate quadratic rate-quantization (R-Q) model. Secondly, a method of determining the quantization parameters (QPs) for the first frames within a group of pictures is proposed. Thirdly, an accurate frame-level bit allocation method is proposed for HEVC. Finally, based on the proposed R-Q model and the target bit allocated for the frame, the QPs are predicted for coding tree units by using rate-distortion (R-D) optimization. We compare our scheme against that of three other state-of-the-art rate control schemes. Experimental results show that the proposed rate control scheme can increase the Bjøntegaard delta peak signal-to-noise ratio by 0.65 dB and 0.09 dB on average compared with the JCTVC-I0094 and JCTVC-M0036 schemes, respectively, both of which have been implemented in an HEVC test model encoder; furthermore, the proposed scheme achieves a similar R-D performance to Wang's scheme, as well as obtaining the smallest bit rate mismatch error of all the schemes.