• ETRI Journal
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• v.28 no.3
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• pp.371-374
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• 2006

We propose and analyze a priority queuing scheme that gives priority in the same class of calls according to their total resource requirements (TRRs). The proposed scheme gives a higher priority to the calls that have a lower TRR over the calls that have a higher TRR. The numerical results show that the proposed priority queuing scheme provides better performance than the traditional queuing schemes in call blocking probability.

• International Journal of Highway Engineering
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• v.15 no.1
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• pp.135-141
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• 2013

PURPOSES: In this study, as part of an effort to develop HUD for public transit, it is proposed that the decision of order priority of contents which will be disposed to bus drivers through HUD for public transit using AHP(Analytic Hierarchy Process) technique. METHODS: In AHP analysis method brainstorming, factor analysis, hierarchical structuring, and weighting analysis were performed by applying a classical analysis method. RESULTS: By the result of analysis it is shown that unlike car drivers, bus drivers prefer information related to bus intervals, bus stop, and door open and close to information related to vehicle running. Also, bus stop information and bus interval information were ranked as first and second place in order priority of HUD contents for public transit by experts. CONCLUSIONS: This method of selecting order priority of HUD contents for public transit can provide a basic foundation for selecting order priority of traffic information contents as well as other HUD contents.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.12B
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• pp.1996-2002
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• 2000

This paper investigates a priority scheme for IEEE 802.11 Carrier Sense Multiple Access/Collision Avoidance (CSMA/CA) protocol in order to provide short access times for priority frames (e.g. time-deadline traffic) even when the overall traffic on the wireless channel is heavy. Under the compatibility constraint for the IEEE 802.11 wireless LANs, two priority systems are simulated: no priority (current IEEE 802.11 standard) for time-deadline traffics and dynamic time-deadline priority. We evaluate algorithms to improve the time-deadline traffic performance using discrete event simulation (DES)

• Proceedings of the IEEK Conference
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• 2002.07b
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• pp.1113-1116
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• 2002

For contents delivery systems, the service is considered in which the utility depends on each priority class. This paper deals with the multiple priority class of the contents delivery system from the viewpoint of the utility. The willingness to pay (WTP) is introduced as a measure of utility, and the optimum condition is analyzed to maximize the total user's utility. For the system with multiple priority classes, the optimum condition is given in terms of the traffic load, wating time for service for each priority class. Systems with the priority classes, 1, 2 and 3 are analyzed, and the effect of the number of priority classes is examined.

• The Journal of Information Systems
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• v.16 no.3
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• pp.91-108
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• 2007

To decide a reasonable investment priority of public enterprises, it is required to have an efficient evaluation standard. However, without having a standard, a budget for those enterprises has been allocated. In this research, for the efficient and reasonable budget allocation, it is discussed how to decide investment priority of information and communication enterprises of the government. In order to examine possible alternatives of the investment priority of information and communication enterprises of the government, seventeen enterprises were chosen from the enterprises of Ministry of Information and Communication. Public benefit, economic benefit, technology, politics, and step-up increase of budget were set up as evaluation standards and 16 specific standards were set up as subordinates. A hierarchical decision model was designed and analyzed by using AHP.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.7 no.11
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• pp.2636-2656
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• 2013

To improve the cooperative efficiency of node cooperation and multiple access performance for multihop wireless networks, a priority-differentiated cooperative medium access control protocol with contention resolution (CRP-CMAC) is proposed. In the protocol, the helper selection process is divided into the priority differentiation phase and the contention resolution phase for the helpers with the same priority. A higher priority helper can choose an earlier minislot in the priority differentiation phase to send a busy tone. As a result, the protocol promptly selects all the highest priority helpers. The contention resolution phase of the same priority helpers consists of k round contention resolution procedures. The helpers that had sent the first busy tone and are now sending the longest busy tone can continue to the next round, and then the other helpers that sense the busy tone withdraw from the contention. Therefore, it can select the unique best helper from the highest priority helpers with high probability. A packet piggyback mechanism is also adopted to make the high data rate helper with packet to send transmit its data packets to its recipient without reservation. It can significantly decrease the reservation overhead and effectively improve the cooperation efficiency and channel utilization. Simulation results show that the maximum throughput of CRP-CMAC is 74%, 36.1% and 15% higher than those of the 802.11 DCF, CoopMACA and 2rcMAC protocols in a wireless local area network (WLAN) environment, and 82.6%, 37.6% and 46.3% higher in an ad hoc network environment, respectively.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.12 no.2
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• pp.92-101
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• 1987

Messages which are entered into communication networks are processed according to the priorities manipulated by serveral queueing disciplines. This study is concerned with one of those disciplines, dynamic priority. We analyzed the everage waiting time for the messages be processed by dynamic priority in queue. The priority is variated by the message's waiting time in queue. The dynamic priority discipline can be classified according as messaged have initial priority or not. Difference of above two discriplines were considered.

• The Transactions of the Korea Information Processing Society
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• v.6 no.11S
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• pp.3251-3259
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• 1999

In this paper, we present a new mechanism applying more strict priority than RIO mechanism proposed as a drop precedence policy of AF classes in differentiated services. In this mechanism, applying strict priority to drop precedence policy, we get better performance on priority level. Simulation results indicate that the proposed mechanism may provide more efficient and more strict priority transmissions as compared to RIO regardless of traffic load.

• Proceedings of the IEEK Conference
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• 2007.07a
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• pp.15-16
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• 2007

In order to provide value-added services, next generation routers should perform packet classification for each incoming packet at wire-speed. In this paper, we proposed hierarchical priority trio (Hptrie) for packet classification. The proposed scheme improves the search performance and the memory requirement by replacing empty internal nodes in ordinary hierarchical trio with priority nodes which are the nodes including the highest priority rule among sub-trie nodes.

• The Transactions of the Korea Information Processing Society
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• v.6 no.11
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• pp.3131-3139
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• 1999

Satisfying the rigid timing requirements of various real-time activities in real-time systems often requires some special methods to tune the systems run-time behaviors. Unbounded blocking can be caused when a high priority activity cannot preempt a low priority activity. In such situation, it is said that a priority inversion has occurred. The priority inversion is one of the problems which may prevent threads from meeting the deadlines in the real-time systems. It is difficult to remove such priority inversion problems in the kernel at the same time to bound the worst case blocking time for the threads. A thread is a piece of executable code which has access to data and stack. In this paper, a new real-time systems. It is difficult to remove such priority inversion problems in the kernel at the same time to bound the worst case blocking time for the threads. A threads is a piece of executable code which has access to data and stack. In this paper, a new real-time server model, which minimizes the duration of priority inversion, is proposed to reduce the priority inversion problem. The proposed server model provides a framework for building a better server structure, which can not only minimize the duration of the priority inversion, but also reduce the deadline miss ratio of higher priority threads.