• International Journal of Advanced Culture Technology
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• 제9권4호
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• pp.363-375
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• 2021

The purpose of this study is to analyze the safety of evacuation using the Pathfinder program for the alert at once, the priority alarm method, the priority alarm method for the four floors above, and the sequential priority alarm method, which is a modification of the priority alarm method specified in the tourist hotel building. Currently, in Korea's National Fire Safety Codes (NFSC), fire alarm methods are compulsorily applied differently depending on the number of floors and total floor area of a building. Although the growth rate is getting faster due to the diversification of building structures, it is still an obstacle to improving evacuation safety to comply with the standardized fire alarm method in NFSC. As a result of the experiment, the evacuation time was found to be faster with the priority alarm method for the four floors above than the priority alarm method applied to the specific firefighting object. Compared to the priority alarm method applied to the tourist hotel, which is a specific firefighting target with 5 or more floors and a total floor area of more than 3,000m2, the time was shortened by 3.7 seconds when measured by applying the priority alarm method for the four floors directly above. This indicates that it is necessary to take measures to select a fire alarm method suitable for the structure and environmental conditions of the building rather than applying the uniform NFSC regulations.

• 대한전자공학회논문지SD
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• 제46권11호
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• pp.34-39
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• 2009

본 논문에서는 일반적으로 사용되는 fixed priority 방식과 round-robin 방식의 장점을 살리고 단점을 극복하기 위해 위 두 방식에 랜덤 함수 매니저를 결합하여 두 방식을 모두 사용할 수 있는 랜덤 함수 중재 방식을 제안하였다. Fixed priority 방식에서는 우선순위가 낮은 마스터의 스타베이션 현상이 발생하는 문제점을 가지고 있으며, round-robin 방식은 중요한 마스터에게 우선권을 줄 수 없는 단점이 있다. 그러나 제안한 랜덤 함수 중재 방식은 F-F:R-R의 비율을 사용자가 임의로 조정할 수 있어서 기존 중재방식의 문제점을 해결할 수 있었다. TLM 시뮬레이션 결과, 마스터의 버스점유율을 32%에서 16%로 사용자가 임의 조절이 가능했으며, 마스터의 스타베이션 현상도 방지할 수 있었다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 A
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• pp.545-547
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• 2004

This paper proposes the novel investment priority decision method for distribution facilities considering the potential failure rate and the influence of customer caused by faults in distribution networks. The Proposed method decides the investment priority of the facilities combining, by the fuzzy rules, the KEPCO's priority decision for investment and the priority decision considering SAIFI(System Average Interruption Frequency Index) and SAIDI(System Average Interruption Duration Index). To verify the performance of the proposed method, these works utilized the projects for weak facility reinforcement planned in KEPCO in the Busan region in 2003 and 2004. The evaluation results showed that the reliability of the KEPCO in the Busan region using the proposed method can be enhanced more than using the conventional KEPCO's method.

• 한국도로학회논문집
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• 제15권1호
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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.

• Environmental Analysis Health and Toxicology
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• 제19권1호
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• pp.81-91
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• 2004

Although it is suggested that risk -based management plan is needed to manage air pollution effectively, we have no resources enough to evaluate all aspects of substances and set priorities. So we need to develop a logical and easy risk-based priority setting method. However, it if impossible that only one generic system that is consistent with all the use is developed. In this study, we proposed a human health risk based priority-setting method for hazardous air pollutants, and ranked priorities for this method. First of all, after investigating previous chemical ranking and scoring systems, we chose appropriate indicators and logics to goal of this study and made a chemical priority ranking method using these. As results, final scores in priority ranking method were derived for 25 substances, and ethylene oxide, acrylonitrile and vinyl chloride were included in high ranks. In addition, same substances were highly ranked when using default values like when using no default, but the scores of hydrofluoric acid and ryan and compounds were sensitive to default values. This study could be important that priorities were set including toxicity type and quality and local inherent exposure conditions and we can set area-specific management guidelines and survey plans as a screening tool.

• 한국정밀공학회지
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• 제15권6호
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• pp.107-115
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• 1998

A path planning using potential field method is very useful for the real-time navigation of mobile robots. However, the method needs high modeling cost to calculate the potential field because of complex preprocessing, and mobile robots may get stuck into local minima. In this paper, An efficient path planning algorithm for multiple mobile robots, based on the potential field method, was proposed. In the algorithm. the concepts of subgoals and obstacle priority were introduced. The subgoals can be used to escape local minima, or to design and change the paths of mobile robots in the work space. In obstacle priority, all the objects (obstacles and mobile robots) in the work space have their own priorities, and the object having lower priority should avoid the objects having higher priority than it has. In this paper, first, potential based path planning method was introduced, next an efficient collision-avoidance algorithm for multiple mobile robots, moving in the obstacle environment, was proposed by using subgoals and obstacle priority. Finally, the developed algorithm was demonstrated graphically to show the usefulness of the algorithm.

• Journal of Electrical Engineering and Technology
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• 제4권1호
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• pp.43-48
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• 2009

The purpose of the this paper is to make decision of the maintenance priority of power distribution system using Time-Varying Failure Rate(TVFR) with interruption cost. This paper emphasizes the practical use of the reliability indices and interruption cost. To make a decision of maintenance priority on power distribution system equipment, the quantification of the reliability level should be represented as a cost. In this paper, the TVFR of power distribution system equipment applied in this paper utilizes analytic method to use the historical data of KEPCO. From this result, the sensitivity analysis on TVFR of equipment was done for the priority, which represents that high priority of the equipment has more effect on system reliability, such as SAIDI or SAIFI, than other equipment. By this priority, the investment plan is established. In this result, customer interruption cost(CIC) could be extracted, and CIC is used as weighting factor to consider a importance of customer. After that, the result calculated the proposal method in this paper is compared with other priority method, such as lifetime, failure rate or only sensitivity.

• 한국콘텐츠학회논문지
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• 제10권7호
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• pp.115-121
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• 2010

실시간 데이터베이스 시스템에서는 높은 우선순위를 갖는 트랜잭션의 선행 처리가 항상 보장되어야 한다. 비관적 병행수행제어 방법은 충돌 발생 시 낮은 우선순위 트랜잭션을 철회 또는 대기시킴으로써 충돌을 해결한다. 그런데 높은 우선순위 트랜잭션이 마감시간을 지키지 못하고 시스템에서 제거되는 경우, 낮은 우선순위 트랜잭션이 불필요하게 철회되거나 대기하는 문제가 발생된다. 본 논문에서 제안하는 방법은 마감시간을 초과할 트랜잭션을 미리 시스템에서 제거한다. 그래서 불필요한 자원 낭비를 막고 낮은 우선순위를 갖는 트랜잭션이 불필요하게 철회되거나 대기하는 문제를 해결한다. 성능평가를 통해 트랜잭션의 마감시간 초과 비율 측면에서 기존의 방법들 보다 우수함을 보인다.

• Journal of applied mathematics & informatics
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• 제31권1_2호
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• pp.147-154
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• 2013

We analyze queueing model with priority scheduling by supplementary variable method. Customers are classified into two types (type-1 and type-2 ) according to their characteristics. Customers of each type arrive by independent Poisson processes, and all customers regardless of type have same general service time. The service order of each type is determined by the queue length of type-1 buffer. If the queue length of type-1 customer exceeds a threshold L, the service priority is given to the type-1 customer. Otherwise, the service priority is given to type-2 customer. Method of supplementary variable by remaining service time gives us information for queue length of two buffers. That is, we derive the differential difference equations for our queueing system. We obtain joint probability generating function for two queue lengths and the remaining service time. Also, the mean queue length of each buffer is derived.

• 한국멀티미디어학회논문지
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• 제8권6호
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• pp.744-752
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• 2005

When the multiple video sources are transmitted together through the channel of fixed bandwidth, an efficient picture quality control is necessary. This paper presents a joint picture quality control method to satisfy the user requirement by priority among the video sources. The better picture quality is assigned to the source of higher priority compared to lower priority. We obtain the bitrate for each source to have a required distortion level among the sources by using an approximate distortion-bitrate model for simple implementation. It is shown by simulation that the proposed bandwidth allocation method can keep almost the user-required picture quality among the sources in comparison to an independent bandwidth allocation method.