• International Journal of Control, Automation, and Systems
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• v.5 no.3
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• pp.317-323
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• 2007

Quality of Service (QoS) in the Internet depends on queuing and sophisticated scheduling in routers. In this paper, we address the issue of managing traffic flows with different priorities. In our reference model, incoming packets are first classified based on their priority, placed into different queues with different capacities, and then multiplexed onto one router link. The fuzzy nature of the information on Internet traffic makes this problem particularly suited to fuzzy methodologies. We propose a new solution that employs a fuzzy inference system to dynamically and efficiently schedule these priority queues. The fuzzy rules are derived to minimize the selected Lyapunov function. Simulation experiments show that the proposed fuzzy scheduling algorithm outperforms the popular Weighted Round Robin (WRR) queue scheduling mechanism.

• Journal of Intelligence and Information Systems
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• v.17 no.1
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• pp.1-16
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• 2011

The real-time ubiquitous environment is required to be able to process a series of sensor data within limited time. The whole sensor data processing consists of several phases : getting data out of sensor, acquiring context and responding to users. The ubiquitous computing middleware is aware of the context using the input sensor data and a series of data from database or knowledge-base, makes a decision suitable for the context and shows a response according to the decision. When the real-time ubiquitous environment gets a set of sensor data as its input, it needs to be able to estimate the delay-time of the sensor data considering the available resource and the priority of it for scheduling a series of sensor data. Also the sensor data of higher priority can stop the processing of proceeding sensor data. The research field for such a decision making is not yet vibrant. In this paper, we propose a queuing time computation algorithm for sensor data processing in real-time ubiquitous environment.

• Journal of KIISE:Computer Systems and Theory
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• v.33 no.6
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• pp.337-343
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• 2006

The Stack Resource Policy (SRP) is a real-time synchronization protocol with some distinct properties. One of such properties is early blocking; the execution of a job is delayed instead of being blocked when requesting shared resources. If SRP is used with dynamic priority scheduling such as Earliest Deadline First (EDF), the early blocking requires that a scheduler should select the highest-priority job among the jobs that will not be blocked, incurring runtime overhead. In this paper, we analyze the runtime overhead of EDF scheduling when SRP is used. We find out that the overhead of job search using the conventional implementations of ready queue and job search algorithms becomes serious as the number of jobs increases. To solve this problem, we propose an alternative data structure for the ready queue and an efficient job-search algorithm with O([log$_2n$]) time complexity.

• Journal of IKEEE
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• v.2 no.1 s.2
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• pp.114-121
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• 1998

This paper proposed a collision avoidance scheme to improve the network performance and priority control scheme to support real-time ATM applications in CIF(Cells in Frames), which carries ATM cells over existing Ethernet interfaces. The proposed scheme has optimized for the two nodes Ethernet, that is a typical CIF network, and doesn't require any hardware modification of existing Ethernet interface card. The collision avoidance scheme gives fair access opprtunities with minimized contention to the nodes by assigning different inter-frame gap to each element of CIF network. The priority control scheme guarantees preemptive transmission of real-time frames to the medium by exchanging queuing status information between two nodes. Therefore in this paper it is shown that CIF network which has both the collision avoidance scheme of MAC layer and the priority control scheme of CIF layer has a improved network performance and supports real-time ATM applications efficiently.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.7B
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• pp.653-663
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• 2002

UMTS/GPRS has its own QoS architecture, but additionally needs to support IP-QoS to provide Internet services. This paper describes an IP-QoS provisioning mechanism in the MPLS-based UMTS/GPRS network. We propose a QoS framework that includes the functional architecture of the MPLS-based GPRS networks and the efficient scheduling mechanism based on Diffserv model. The proposed scheduling mechanims is especially focused on the QoS support for real-time services. It also includes a new buffer management scheme that combines the priority queuing and weighted round robin method. The ns-2 simulator has been used to verify the validity of the proposed scheduling method.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.42 no.12
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• pp.95-102
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• 2005

This paper is purpose for improvement performance wireless lan of IEEE802.11a/b/g. Access point utilized a single server, multi-queuing system, FIFS system model to adapted priority multi-bufferto be alteration packet type. The main purpose of the paper improve the transmission rate and the performance of access point to settle transmission delay for load in MAC, has priority multi-buffer. We use experimentation to obtain our model of the access point and buffer-related parameters. Using our test design, we are able to extract the parameters of an analytic equation giving the average service time of a packet as a function of packer IP payload.

• Asia pacific journal of information systems
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• v.7 no.3
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• pp.109-124
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• 1997

Pricing information services, where congestion can threaten the efficient operation of information systems, has been studied in economics and information systems literature, Recent explosion of the Internet ana proliferation of multimedia content over the Internet have rekindled the research interest in designing pricing schedules for differentiated information services, In order for the information system to effectively serve users having heterogeneous needs, pricing rules for discriminated services should be considered. At the same time, when individual users' interest does not align with that of the organization that individual users belong to, organization-wide pricing policy should be devised to improve the value of the services rendered by the system. This paper, using a priority queuing model, addresses the need for such on incentive-compatible pricing for different information services.

• Journal of Korean Society for Quality Management
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• v.31 no.3
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• pp.114-125
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• 2003

In this paper, we deal with the problem of modeling of agent-based robot manufacturing cell. Its role is becoming increasingly important in automated manufacturing systems. For Object Oriented & Queueing Petri Nets (OO&QPNs), an extended formalism for the combined quantitative and qualitative analysis of different systems is used for structure and performance analysis of mobile robotic cell. In the case study, the OO&QPN model of a mobile robotic cell is represented and analyzed, considering multi-class parts, non-preemptive priority and alternative routing. Finally, the comparison of performance values between Shortest Process Time (SPT) rule and First Come First Serve (FCFS) rule is suggested. In general, SPT rule is most suitable for parts that have shorter processing time than others.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.3
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• pp.1265-1278
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• 2017

Dynamic task scheduling is one of the most popular research topics in the cloud computing field. The cloud scheduler dynamically provides VM resources to variable cloud tasks with different scheduling strategies in cloud computing. In this study, we utilized a valid model to describe the dynamic changes of both computing facilities (such as hardware updating) and request task queuing. We built a novel approach called Policy Iteration Scheduling (PIS) to globally optimize the independent task scheduling scheme and minimize the total execution time of priority tasks. We performed experiments with randomly generated cloud task sets and varied the performance of VM resources using Poisson distributions. The results show that PIS outperforms other popular schedulers in a typical cloud computing environment.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.22 no.1
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• pp.127-138
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• 1997

In this paper, we study new HOL-LJ scheme to guarantee the QoW of low priority cell with simple hardware which is not realizable in previously proposed HOL and HOL-PJ. the performance of the proposed scheme is evaluated by analysing an equivalent /M/M/1/N queuing system. In case of using the proposed scheme, we confirmed that good performance compared with HOL-PJ through simpulation and mathematical analysis. We also applied HOL-LJ algorithm to convetional Dual Buffer and Partial Buffer, and we analyzed the performance through computer simulation.