• IEIE Transactions on Smart Processing and Computing
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• v.5 no.5
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• pp.310-318
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• 2016

Emerging technologies such as the Internet of Things (IoT) and the Advanced Driver Assistant System (ADAS) often have image transmission functions with tough constraints, like low power and/or low delay, which require that they adopt line-based, low memory compression methods instead of existing frame-based image compression standards. Bit rate control in the conventional frame-based compression systems requires a lot of hardware resources when the scope of handled data falls at the frame level. On the other hand, attempts to reduce the heavy hardware resource requirement by focusing on line-level processing yield uneven image quality through the frame. In this paper, we propose a bit rate control that maintains consistency in image quality through the frame and improves the legibility of text regions. To find the line characteristics, the proposed bit rate control tests each line for ease of compression and the existence of text. Experiments on the proposed bit rate control show peak signal-to-noise ratios (PSNRs) similar to those of conventional bit rate controls, but with the use of significantly fewer hardware resources.

• Journal of Information Display
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• v.10 no.1
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• pp.37-44
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• 2009

AiPi technology incorporates an embedded clock and control scheme with a point-to-point bus topology, thereby having the smallest possible number of interface lines between a timing controller and column drivers. A point-to-point architecture boosts the data rate and reduces the number of interface lines, because impedance matching can be easily achieved. An embedded clock and control scheme is implemented by means of multi-level signalling, which results in a simple clock/data recovery circuitry. A 46" AiPi-based 10-bit FHD prototype requires only 20 interface lines, compared to 38 lines for mini-LVDS. The measured maximum data rate per data pair is more than 800 Mbps.

• Journal of Korean Society of Transportation
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• v.22 no.1 s.72
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• pp.63-72
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• 2004

In conducting traffic safety programs, it is very important to identify hazardous sites in appropriate manner. The rate qualify control method is generally used in identifying hazardous sites since it can interpret the sites in the statistic aspects. The rate qualify control method is based on the assumption that the occurrences of traffic crashes follow the Poisson's distribution in which the expected value of traffic crashes equals the variance of those. However, there is greater variability than expected statistically, we call this phenomenon over dispersion. This study analyzed the problem related to the rate quality control method under the over dispersed data, and established a methodology to solve the problem. As a result of test on the basis of the field data, the new approach produced more reasonable results than those of the Poisson based rate quality control method.

• Journal of Drive and Control
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• v.13 no.4
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• pp.7-13
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• 2016

This paper presents the meter-out and meter-in speed control characteristics of a pneumatic cylinder with relief valve type cushion device. The piston displacement and velocity are measured to investigate high speed driving performance with variation of the pressure setting in relief valve, air supply pressure, load mass, the supply and exhaust flow rate from the cylinder. Also, the internal pressures and temperatures driving pressure and cushion chamber are measured. The piston displacements and velocities of meter-out and meter-in control are compared experimentally determined data. A comparison experimental data meter-out and meter-in control show that a relief valve type cushion device is suitable for high speed pneumatic cylinders. The desired response characteristics of piston displacement and velocity are satisfactory adjust the pressure setting of a relief valve with varying system parameters such as air supply pressure, load mass and controlled flow rate.

• Journal of Institute of Control, Robotics and Systems
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• v.5 no.7
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• pp.876-882
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• 1999

It is difficult to determine the feeding rate of coagulant in the water treatment process, due to nonlinearity, multivariables and slow response characteristics, etc. To deal with this difficulty, the genetic-fuzzy system was used in determining the feeding rate of the coagulant. The genetic algorithms are excellently robust in complex optimization problems. Since it uses randomized operators and searches for the best chromosome without auxiliary informations from a population consists of codings of parameter set. To apply this algorithms, we made the lookup table and membership function from the actual operation data of the water treatment process. We determined optimum dosages of coagulant(LAS) by the fuzzy operation, and compared it with the feeding rate of the actual operation data.

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.265-266
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• 2008

TD-SCDMA combines TDMA and CDMA components to provide more efficient use of radio resources. However, since the same frequency band is used in both the uplink and downlink, serious interference may occur if the base stations are not synchronized. The interference caused by different transmission directions between neighboring cells is called cross-slot interference. This paper proposes a data rate control algorithm that can decrease the cross-slot interference in TD-SCDMA.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.22 no.2
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• pp.259-267
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• 1997

The advent of B-ISDN using ATM(asynchronous transfer mode) made possible a variety of new multimedia services, however it also created a problem of congestion control due to bursty nature of various traffic sources. To tackle this problem, UPC/NPC(user parameter control/network parameter control) have been actively studied and DRLB(dynamic rate leaky bucket) algorithm, in which the token generation rate is changed according to states of data source andbuffer occupancy, is a good example of the UPC/NPC. However, the DRLB algorithm has drawbacks of low efficiency and difficult real-time implementation for bursty traffic sources because the determination of token generation rate in the algorithm is based on the present state of network. In this paper, we propose a more plastic and effective congestion control algorithm by combining the DRLB algorithm and neural network based prediction to remedy the drawbacks of the DRLB algorithm, and verify the efficacy of the proposed method by computer simulations.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.3
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• pp.637-644
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• 2004

This paper proposed and implemented the adaptive transmission middleware for video streaming, which is able to support the adaptive transmission of video data to the fluctuating changes of network environment in the packet-based network and the properties of transmitted video data. The adaptive transmission middleware is made up SR-RTP-based transfer module and TFRC(TCP Friendly Rate Control)-based transfer-rate control module. The SR-RTP-based transfer module supports RTP-based real-time transfer of video data and packet retransmission scheme retransmitting the high-priority packets selectively in the damaged video data to reduce the error induced by the packet loss. Sharing the transmission bandwidth of network with the TCP-based data transfer, the TFRC-based transfer-rate control module controls the transfer rate of video data according to the most allowable transmission bandwidth in the network, so that the transfer rate is controlled adaptively to the fluctuating changes of transmission bandwidth. This paper, for the experiment, applied the adaptive transmission middleware to video streaming in the external Internet environment, and analyzed the effective frame transfer rate and the degree of the streaming jitter to evaluate the performance of packet-loss recovery and adaptive transfer rate control. In the external Internet environment where the packet-loss rate is high a bit, the relatively high streaming performance was showed compared with the case that didn't apply the adaptive transmission middleware.

• 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.

• International Journal of Control, Automation, and Systems
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• v.4 no.1
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• pp.53-62
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• 2006

In this paper, ATM network congestion control with explicit rate feedback is considered. In ATM networks, delays commonly appear in data transmission and have to be considered in congestion control design. In this paper, a bounded single round delay on the return path is considered. Our objective is to design an explicit rate feedback control that achieves a robust optimal $H_2$ performance regardless of the bounded time-varying delays. An optimization approach in terms of linear matrix inequalities (LMIs) is given. Saturation in source rate and queue buffer is also taken into consideration in the proposed design. Simulations for the cases of single source and multiple sources are presented to demonstrate the effectiveness of the design.