• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.27 no.4
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• pp.23-30
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• 2013

Reliability Centered Maintenance(RCM) is one of most widely used methods in the modern power system to schedule a maintenance cycle and determine the priority of inspection. A precedence study for the new structure of rearranged system should be performed due to introduction of additional installation. This paper proposes a new method to evaluate the priority of maintenance and inspection of the power system facilities. In order to calculate that risk index, it is required that the reliability block diagram should be analyzed for the power system. Additionally, a fault cause analysis is also performed through the event-tree analysis.

• Journal of the Korean Operations Research and Management Science Society
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• v.27 no.1
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• pp.1-17
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• 2002

The objective of this paper is to develop a new priority setting algorithm that considers the cross-impact of the future technology alternatives and that satisfies the final goal of the technology management through multi-hierarchy evaluation criteria. By combining the Analytic Hierarchy Process (AHP) model, which is a well-known priority setting model, and Cross Impact Analysis (CIA) model, which is a technological forecasting method that considers cross-impact among R&D Items, we developed an Integrated Cross-Impact Hierarchical (CIH) model, which sets the priority by considering technological forecasting and technology dependency simultaneously. A step-by-step numerical example of the model developed here is presented as backup of its practicality.

• Proceedings of the Korea Society for Simulation Conference
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• 2003.11a
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• pp.67-74
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• 2003

Stream servers are for supplying multimedia stream data to users through the internet such as movies and musics without discontinuation. A typical stream server is designed roughly by considering the characteristics of stream services and by employing processors, memory, PCI bus, Ethernet, TOE and disks. This study focuses on deciding the priority for using resources such as PCI bus, buffer memory and TOE buffer, which have limited capacities in a typical stream server. The simulation study shows that the top priority for using PCI bus for normal streaming services should be given to the operation that sends data from buffer memory to TOE buffer Giving priority for using PCI bus to other operation such as sending data from disks to memory results in deadlock Phenomenon.

• Journal of the Korean Society of Food Culture
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• v.27 no.2
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• pp.157-171
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• 2012

This study was performed to approach Korean food proverbs from the stance of food ethics. Both modern principles and traditional principles of food ethics were applied to select proverbs. The modern principles include a respect for life, justice, environmental preservation, and the priority of safety. The traditional principles were longevity and good health, poverty (escaping) and wealth (pursuing), eating luck and fortune, priority of food, virtue, and taste and quality (economics). All the principles except environmental preservation and the priority of safety have adequate food proverbs, since environmental disruption and food safety were not serious issues in the past.

• Journal of the Korea Safety Management & Science
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• v.13 no.1
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• pp.161-166
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• 2011

This study proposes a priority model for program directors in charge of Corporate Social Contribution to make the best decision. This empirical analysis aims to discover the most significant area among various programs of Corporate Social Contribution Activities. The Analytical Hierarchy Process (AHP) is used to test the priority model. The study attempts to demonstrate how the model helps providing better decision choices in corporate practices. The priority preference in Corporate Social Contribution Activities programs among corporate social contribution practitioners, PR professors and NGO activists are studied for their priority on corporate social contribution programs, among they valued com mon benefit social activity most important.

• Journal of Communications and Networks
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• v.14 no.5
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• pp.487-494
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• 2012

A standard paradigm for the allocation of wireless resources in communication demands symmetry, that is, all users are assumed to be on equal footing and hence get equal shares of the system's communication capabilities. However, there are situations in which "prime users" should be given priority, as for example in the transmission of emergency messages. We examine prioritization policies that could be implemented at the physical layer and propose a new one, termed interference priority (IP), which is shown to have excellent performance. We evaluate the performance of these prioritization techniques both in controlled settings and within the context of a full cellular system and discuss the impact of prioritized use of resources on the unprioritized users.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.89-89
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• 2000

The Current CORBA has many drawbacks to be deployed successfully in real-time system applications. Recently, OMG adopted Real-Time CORBA specification. In this paper, we report our efforts on an implementation of Priority Model of Real-Time CORBA spec., which is one of the most important components in Real-Time CORBA spec. The improvement of real-time performances of our implementation is verified experiments.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2000.10a
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• pp.302-305
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• 2000

The operation of a networked computing system (NCS), such as Internet, can be viewed as a resource allocation problem, and can be analyzed using the techniques of mathematical modeling. We define a general NCS and translate that setup into a model of an economy. The preferences of users are taken as primitives, and servers in the network are viewed as productive firms with priority input queues. Each sewer charges a rental price for its services by priority class. We characterize optimal system allocation, and derive formulae for supporting rental prices and priority premia such that the aggregated individual user demands do not exceed optimal levels and waiting-time expectations are correct. Our economic approach has the added benefit of providing a sound basis for evaluating NCS investment alternatives, using a process analogous to free entry and exit in free-enterprise economies.

• Journal of information and communication convergence engineering
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• v.15 no.1
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• pp.28-36
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• 2017

The medium access control (MAC) protocol based on dynamic time division multiple access/time division duplex (TDMA/TDD) is responsible for random access control and radio resource allocation in dynamic traffic environments. These functions of random access and resource allocation are very important to prevent wastage of resources and improve MAC performance according to various network conditions. In this paper, we propose new random access and resource allocation schemes to guarantee quality of service (QoS) and provide priority services in a dynamic TDMA/TDD system. First, for the QoS guarantee, we propose an adaptive random access and resource allocation scheme by introducing an access probability. Second, for providing priority service, we propose a priority-based random access and resource allocation scheme by extending the first adaptive scheme in both a centralized and a distributed manner. The analysis and simulation results show that the proposed MAC protocol outperforms the legacy MAC protocol using a simple binary exponential backoff algorithm, and provides good differential performance according to priorities with respect to the throughput and delay.

• Industrial Engineering and Management Systems
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• v.7 no.1
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• pp.99-107
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• 2008

This paper is concerned with scheduling in Flexible Manufacturing Systems (FMS) using a Fuzzy Logic (FL) approach. Four fuzzy input variables: machine allocated processing time, machine priority, machine available time and transportation priority are defined. The job priority is the output fuzzy variable, showing the priority status of a job to be selected for the next operation on a machine. The model will first select the machines and then assign operations based on a multi-criteria scheduling scheme. System/machine utilization, minimizing mean flow time and balancing machine usage will be covered. Experimental and comparative tests indicate the superiority of this fuzzy based scheduling model over the existing approaches.