• International Journal of Automotive Technology
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• v.8 no.1
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• pp.39-48
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• 2007

This paper addresses the problem of period and priority assignment in networked control systems (NCSs) using a fixed priority scheduler. The problem of assigning periods and priorities to tasks and messages is formulated as an optimization problem to allow for a systematic approach. The temporal characteristics of an NCS should be considered by defining an appropriate performance index (PI) which represents the temporal behavior of the NCS. In this study, the sum of the end-to-end response times required to process all I/Os with precedence relationships is defined as a PI. Constraints are derived from the task and message deadline requirements to guarantee schedulability. Genetic algorithms are used to solve this constrained optimization problem because the optimization formulation is discrete and nonlinear. By considering the effects of communication, an optimum set of periods and priorities can be holistically derived.

• 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.8 no.11
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• pp.4189-4202
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• 2014

In this paper, we propose a priority-based unequal error protection scheme of data partitioned H.264/AVC video with hierarchical quadrature amplitude modulation. In order to map data with higher priority onto the most significant bits of QAM constellation points, a priority sorting method categorizes different data partitions according to the unequal importance factor of encoded video data in one group of pictures by evaluated the average distortion. Then we propose a hierarchical quadrature amplitude modulation arrangement with adaptive constellation distances, which takes into account the unequal importance of encoded video data and the channel status. Simulation results show that the proposed scheme improves the received video quality by about 2 dB in PSNR comparing with the state-of-the-art unequal error protection scheme, and outperforms EEP scheme by up to 5 dB when the average channel SNR is low.

• Journal of the Korean Chemical Society
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• v.37 no.6
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• pp.590-598
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• 1993

The simultaneous analysis of samples, 16 organic pesticides in water among 129 priority pollutants listed by EPA, was performed by GC-ECD (electron capture detector) and GC/MS-SIM (selected ion monitoring). Two extraction procedures, liquid-liquid extraction (LLE) and solid-phase extraction (SPE), were studied as an extraction and concentration method. Accuracy and precision of the methods were measured by the calculation of mean recovery and mean relative standard deviation. Finally, the detection limits, the experimental limitations, and prospects were discussed.

• Analytical Science and Technology
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• v.10 no.6
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• pp.395-402
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• 1997

The comparison study between EPA method 3050 and the test method offered by Ministry of Environment in Korea was performed to investigate a matrix effect on extraction. In this study, 12 inorganic priority pollutants(Cd, Cr, Cu, Pb, Ni, Zn, As, Sb, Se, Hg, Be, Tl) were spiked to the sludges and estuary sediment samples. The extracts were analyzed by AAS, HG-AAS, and ICP/MS. Results were discussed in terms of recoveries, relative standard deviations, and the method detection limits. Mean recovery of the elements except As, Sb, and Se was 93% when the procedure of EPA method was applied. The Korean extraction method, however. showed a significant matrix effect to give very poor recoveries.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2001.10a
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• pp.242-245
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• 2001

This study is aimed to design a priority setting algorithm necessary for evaluating and selecting interdependent R&D planning system alternatives. In case that the relationship of technology alternatives is interdependent, a relative importance as occurrence or nonoccurrence of the technology alternatives viewed from the future time varies. So, we are subject to design the evaluation process considering a cross- impact of future technology alternatives. Thus, we apply the cross impact analysis (CIA) model to consider the cross-impact among interdependent system alternatives. Also, the analytic hierarchy process(AHP) model is applied to determine the priority of alternatives by taking the pair-wise comparison among factors.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2000.04a
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• pp.122-125
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• 2000

The Analytic Hierarchy Process (AHP), a decision making model, which is more applicable than other methods to R&D project selection, particularly when it is applied to intangibles. The objective of this paper is to develop an extended model of the AHP which Is linked to Cross Impact Analysis to assist in the ranking of a large number of technological alternatives. In this study, we developed a priority setting algorithm which considers the cross-impact of the future technology alternatives and thus developed an integrated cross-impact hierarchical decision-making model, which sets the priority by considering technological forecasting and technology dependency

• Proceedings of the Korea Information Processing Society Conference
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• 2014.11a
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• pp.227-230
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• 2014

LTE 3GPP standard defines several QCI (QoS Class Identifier) classes to provide differential QoS, depending on the requirements of different user applications.These QCI values have been characterized in terms of priority, packet loss and delay budget. In spite of the availability of this robust QoS framework in LTE, there is no such scheduling algorithm that has its working principle based on this framework. The responsibility of fulfilling the user requirements, while satisfying the service class requirements is left upon the cellular service provider and it is an open issue at present. To solve this problem, we have proposed a MAC scheduler, which defines the priority of different users based on their bearer specification and provides desired QoS in terms of the achieved throughput through the resource block allocation based on calculated user priority.

• Proceedings of KOSOMES biannual meeting
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• 2017.11a
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• pp.155-155
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• 2017

• Journal of applied mathematics & informatics
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• v.7 no.2
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• pp.617-627
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• 2000

ATM networks support diverse traffic types with different service requirement such as data, voice, video and image. This paper analyzes a dynamic priority queue to satisfy Quality of Service (QoS) requirements of traffic. to consider the burstiness of traffic, we assume the arrival to be a Markovian arrival process(MAP) . Performance measures such as loss and delay are derived, Finally, some numerical results show the performance of the system.