• Journal of Advanced Navigation Technology
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• v.18 no.4
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• pp.268-277
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• 2014

It is very important to correlate flight plan for safe and prompt ATC(air traffic control) operation. In this paper, we design CWP(controller working position) MRT(multi radar tracking) processing module to achieve improvement of overall ATC automation system's performance by minimizing network traffic overload when correlating MRT with flight plan. This implemented module can guarantee efficiency and safety of ATC automation system by applying distributed correlated manner, and reduce network usage by using encoded flight plan correlated MRT data format. We found that this module has 8.54~12.11% lower network usage and 8.37~11.27% higher network traffic fairness than the module using standalone manner.

• IE interfaces
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• v.13 no.4
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• pp.738-744
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• 2000

This Paper presents a method for unfinished work transition probability distribution of modulated $n^*D/D/l$ queue with overload period. The Modulated $n^*D/D/l$ queue is well known as a performance analysis model of ATM multiplexer with superposition of homogeneous periodic on-off traffic sources. Theory of probability by conditioning and results of $N^*D/D/l$ queue are used for analytic methodology. The results from this paper are expected to be applied to general modulated $n^*D/D/l$ queue.

• Journal of Digital Convergence
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• v.10 no.1
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• pp.323-333
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• 2012

Network traffic demand is increasing explosively because of various smart equipment and services on smart era. It causes of traffic overload for wireless and wired network. Network management system is very important to control the explosion of data traffic. It uses SNMP to communicate with various network resources for management functions and creates lots of management traffic. Those are can be serious traffic congestion on a network. I propose an improving function of SNMP to minimize unnecessary traffics between manager and agent for collecting the Trend Analysis Information which is mainly used to monitor and accumulate for a specific time period in this paper. The results of test show it has compatibility with the existing SNMP and greatly decreases the amount of network traffic and response time.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.2
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• pp.687-708
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• 2017

The machine-to-machine (M2M) communication is featured by tremendous number of devices, small data transmission, and large uplink to downlink traffic ratio. The massive access requests generated by M2M devices would result in the current medium access control (MAC) protocol in LTE/LTE-A networks suffering from physical random access channel (PRACH) overload, high signaling overhead, and resource underutilization. As such, fairness should be carefully considered when M2M traffic coexists with human-to-human (H2H) traffic. To tackle these problems, we propose an adaptive Slotted ALOHA (S-ALOHA) and time division multiple access (TDMA) hybrid protocol. In particular, the proposed hybrid protocol divides the reserved uplink resource blocks (RBs) in a transmission cycle into the S-ALOHA part for M2M traffic with small-size packets and the TDMA part for H2H traffic with large-size packets. Adaptive resource allocation and access class barring (ACB) are exploited and optimized to maximize the channel utility with fairness constraint. Moreover, an upper performance bound for the proposed hybrid protocol is provided by performing the system equilibrium analysis. Simulation results demonstrate that, compared with pure S-ALOHA and pure TDMA protocol under a target fairness constraint of 0.9, our proposed hybrid protocol can improve the capacity by at least 9.44% when ${\lambda}_1:{\lambda}_2=1:1$and by at least 20.53% when ${\lambda}_1:{\lambda}_2=10:1$, where ${\lambda}_1,{\lambda}_2$ are traffic arrival rates of M2M and H2H traffic, respectively.

• Proceedings of the IEEK Conference
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• 2004.06a
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• pp.115-118
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• 2004

An abrupt increase of traffic-load in cellular CDMA systems can cause overload and degrade the quality of service (QoS) due to the insufficient radio resources. In this paper, we propose a joint coverage and resource management (JCRM) scheme which can improve the QoS degradation and spectrum utilization. The JCRM scheme hands over overloaded traffic to the neighboring cells by virtually reducing a heavily loaded cell coverage and allocates radio resources based on the necessary handover probability. The proposed scheme can be applied to the existing cellular CDMA systems as well as adaptive coverage management schemes for next generation mobile communication systems.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.29 no.1
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• pp.37-46
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• 2015

In order to charge EVs, they have to be connected to distribution system. Therefore, if unprecedented numbers of EVs are connected to power systems, it could result in deterioration of power quality, overload, and other system problems. In this paper, the effects of voltage sag on the distribution system due to the connection of EVs is evaluated by considering related field data of Republic of Korea such as the number of gasoline-fueled vehicles, seasonal load of power system and the monthly and daily real-time traffic volume. The distribution system and EVs are modeled using the Electro Magnetic Transients Program (EMTP).

• Korean System Dynamics Review
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• v.4 no.2
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• pp.131-151
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• 2003

Traffic congestion stems from the widespread desires of people to purse certain goals that inevitably overload existing roads every day. he a transportation policy, congestion toll system has been implemented in Seoul, since 1996. The growing concerns on whether the system would achieve sustained results in the future motivated us to investigate the effectiveness of this policy. Developing and running the congestion toll simulation model, we find that this policy is not an effective policy in the long m. The paper indicates the power of system dynamics approach as a tool for evaluating complex policy like a congestion toll, and suggest that city transportation policy maker should approach the problem with systems thinking and analyze the effectiveness of policy on the basis of understanding the dynamic relationships among subsystems.

• The Transactions of the Korea Information Processing Society
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• v.4 no.11
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• pp.2822-2831
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• 1997

A B-ISDN network based on ATM must support several kinds of transport services with different traffic characteristics and service requirements. There is neither link-by-link flow control nor error control in the ATM layer. For different services, different flow/error controls could be performed at the AAL layer or at a higher Iayer(e.g. transport layer). In traditional data networks, the window now control mechanism combined with error control was used prevalently. But, the window flow control mechanism might be useless in ATM networks because the propagation delay is too large compared with the transmission rate. In this paper, we propose a simple flow control mechanism, called RCT(Rate Control for end-to-end Transport), for end-to-end data transport. The RCT shows acceptable performance when the average overload period is bounded by a certain time.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.4
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• pp.451-453
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• 2016

In this paper, we propose a Load Balance System for SFC based on DLP solution. SFC based on DLP solution does not distribute to the user data and each DLP server manages all traffic generated by the user device. When using existing algorithms such as the Load Balance Round Robin, Least Connection does not consider the resource usage of DLP server so traffic is not efficiently distributed due to different user traffic usage. It causes system failure and overload of the DLP server. Therefore, we propose the architecture of a Load Balance system for SFC based on DLP solution to perform the Load Balance based on the resource usage of DLP server through a LBM server in this paper.

• Journal of Communications and Networks
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• v.18 no.3
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• pp.513-522
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• 2016

We propose a mechanism for monitoring load in quality of service (QoS)-enabled wireless networks and show how it can be used for network management as well as for dynamic pricing. Mobile network traffic, especially video, has grown exponentially over the last few years and it is anticipated that this trend will continue into the future. Driving factors include the availability of new affordable, smart devices, such as smart-phones and tablets, together with the expectation of high quality user experience for video as one would obtain at home. Although new technologies such as long term evolution (LTE) are expected to help satisfy this demand, the fact is that several other mechanisms will be needed to manage overload and congestion in the network. Therefore, the efficient management of the expected huge data traffic demands is critical if operators are to maintain acceptable service quality while making a profit. In the current work, we address this issue by first investigating how the network load can be accurately monitored and then we show how this load metric can then be used to provide creative pricing plans. In addition, we describe its applications to features like traffic offloading and user satisfaction tracking.