• The Transactions of the Korea Information Processing Society
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• v.6 no.12
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• pp.3652-3661
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• 1999

To support multimedia applications such as a multimedia communication systems and multimedia broadcasting, an operating system need to predict their timing-constraints. So, In this real-time systems, we must solve the priority inversion problem that may make the behavior of unpredictable systems and need a real-time server model that provides a better preemptability and minimizes a system overhead. In current real-time systems, the single thread server model, the worker model and the dynamic server model are being used for synchronization but they cannot propose an effective structure for managing shared resources. In this paper, the priority inheritance protocol is used to solve the priority inversion problem and the hybrid prioritized worker model is proposed, which can provide a more effective structure and a faster response time minimizing a system overhead. The hybrid prioritized worker model is to combine the static and the dynamic prioritized worker model, and have a better performance than other models in response time which is an important factor in a real-time system.

• Journal of the Korean Association of Geographic Information Studies
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• v.11 no.2
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• pp.132-147
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• 2008

So far ubiquitous service (u-service) priority has seldom been empirically examined based on the customer's view. It is usual to prioritize the relative importance of u-service variables by the supplier's intuition and a few specialist's experienced knowledge. Such approaches have the disadvantage that they provide only limited empirical information on the field practices in relation to u-service since customer demand of u-service is poorly defined despite abundant interest in this problem. Therefore, the aim of this research was to develop u-service priority model in the context of multi-criteria framework integrating customer and supplier's view, using high technology acceptance theory as major controlling factors. An important question was how to measure or represent criteria that is important to u-service and should be included in a priority model. The selection criteria for the model variables were derived from high technology acceptance theory and AHP approach through the analysis of frequency count, elimination of overlapping factors and brainstorming with specialists. Daegu showed top-rankings in transportation-aid service, guidance service for the eyesight disabled and u-telematics service. In contrast, disaster prevention service and industrial specialized town service ranked highly in the typical supplier's approach were not a dominant determining factor in the u-service priority. The model identified the fact that typical high priority service in terms of supplier's view did not necessarily accompany the important predictor for the u-service priority.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.109-113
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• 2011

수자원사업은 합리적이고 신뢰성 있는 의사결정이 필요한데 그동안 주로 경제성분석에 의존하여 왔다. 본 연구는 경제성분석위주의 기존 방법을 탈피하여 사업 필요성과 투자 타당성을 다양한 각도로 평가할 수 있는 합리적이고 객관적인 수자원사업 대안선정과 투자우선순위결정 방법을 도출하고자 하였다. 이를 위해, 대안 간에 동일한 기준으로 종합평가점수를 산정하여 우선순위를 결정할 수 있도록 다기준의사결정모형을 개발하였다. 적용결과는 취약성 기준에 큰 영향을 받으며, 정책적 기준, 경제성 기준의 순으로 분석되었다. 이는 전문가 설문에 의한 평가기준별 가중치의 영향으로, 수자원사업은 단순히 경제성 분석만으로 평가를 해서는 안 됨을 의미한다. 본 연구는 대규모의 예산이 투입되는 수자원사업에 대한 효율성과 취약지역에 대한 형평성을 제고하는데 기여할 수 있을 것으로 판단된다.

• Journal of Korea Port Economic Association
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• v.30 no.1
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• pp.159-173
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• 2014

This study is key competence port logistics companies analyze the priorities of evaluation factors. key competence index of NCS(National competency standard) was designed on the basis of the research model. The priorities of evaluation factors were analyzed using AHP method. The results of the analysis of 1 layer's key competence priorities are as follows: Interpersonal skills(0.217), communication skills(0.153), ability to develop problem(0.148), ability to understand the organization(0.103), and resource management skills(0.090), self-development ability and professional ethics(0.070), information skills(0.065), technical skills(0.049), numeracy skills(0.035).

• The KIPS Transactions:PartC
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• v.8C no.6
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• pp.793-805
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• 2001

In the recent priority system, high-priority packet will be served first and low-priority packet will be served when there isn\`t any high-priority packet in the system. By the way, even high-priority packet can be blocked by HOL (Head of Line) contention in the input queueing System. Therefore, the whole switching performance can be improved by serving low-priority packet even though high-priority packet is blocked. In this paper, we study the performance of preemptive priority in an input queueing switch for high speed switch system. The analysis of this switching system is taken into account of the influence of priority scheduling and the window scheme for head-of-line contention. We derive queue length distribution, delay and maximum throughput for the switching system based on these control schemes. Because of the service dependencies between inputs, an exact analysis of this switching system is intractable. Consequently, we provide an approximate analysis based on some independence assumption and the flow conservation rule. We use an equivalent queueing system to estimate the service capability seen by each input. In case of the preemptive priority policy without considering a window scheme, we extend the approximation technique used by Chen and Guerin [1] to obtain more accurate results. Moreover, we also propose newly a window scheme that is appropriate for the preemptive priority switching system in view of implementation and operation. It can improve the total system throughput and delay performance of low priority packets. We also analyze this window scheme using an equivalent queueing system and compare the performance results with that without the window scheme. Numerical results are compared with simulations.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.10
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• pp.2500-2506
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• 2015

Proposal assessments for new weapon system development such as C4I system have been applying a qualitative assessment. The main problem of qualitative assessment is that the results vary depending on the evaluator's subjective preferences and priorities. Also, if there is no discrimination of technical skills degrade, the company will be selected by bid price regardless of technical power. In order to making a fairness, We need a method to compensate for the evaluator's subjectivity and to enhance discrimination. Previous standardization method is limited because targets of the proposal assessment are minority and have similar skill level. So, The new standardized evaluation methods applicable to the proposal was presented. This way is using the priority instead of the score and has better performance than existing methods as the target numbers are smaller.

• The Journal of the Korea Contents Association
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• v.10 no.7
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• pp.115-121
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• 2010

It always must guarantee preceding process of the transaction with the higher priority in real-time database systems. The pessimistic concurrency control method resolves a conflict through aborting or blocking of a low priority transaction. However, if a high priority transaction is eliminated in a system because of its deadline missing, an unnecessary aborting or blocking of a low priority transaction is occurred. In this paper, the proposed method eliminates a transaction that is about to miss its deadline. And it prevents needless wastes of resources and eliminates unnecessary aborting or blocking of a low priority transaction. It is shown through the performance evaluation that the proposed method outperforms the existing methods in terms of the deadline missing ratio of transactions.

• Proceedings of the Korea Water Resources Association Conference
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• 2023.05a
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• pp.215-215
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• 2023

누수는 상수도시스템 내에서 발생할 수 있는 대표적인 비정상상황 중 하나이다. 누수는 발생 직후부터 경제적으로 직접적인 영향을 미치는 것과 함께 토사 내에서 유입되는 이물질 등으로 수질적인 문제 또한 발생할 수 있다. 이와 같은 이유로 누수는 발생에 대한 신속한 인지가 요구되며 이에 따른 신속한 복구가 필요하다. 하지만 기존의 데이터 기반 누수 탐사방법은 일반적으로 누수의 유무만을 인지하기 때문에 발생한 누수에 대한 규모의 정량적인 평가가 어려우며 이는 현재의 누수탐사 방법이 누수의 규모에 따른 복구 우선순위를 고려하기에는 부적절한 방법이라는 것을 의미한다. 따라서, 본 연구에서는 다중 누수시나리오 대해 누수 여부뿐만 아니라 누수 규모, 위치 등을 식별할 수 있는 수리해석 모델 기반 누수탐사 기법을 개발하였고, 이 기법을 활용하여 정량적인 누수량을 식별하여 누수 규모에 따른 누수복구 우선순위를 선정하는 프레임워크를 개발하였다. 이때, 누수복구 우선순위 선정 시 수리학적, 경제적, 사회적 인자 등을 고려하였으며, 각 인자 별 가중치를 통해 최종 복구 우선순위를 선정하였다.

• Proceedings of the Korea Water Resources Association Conference
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• 2019.05a
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• pp.404-404
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• 2019

우리나라는 수자원장기종합계획과 유역종합치수계획의 수립을 통해 수자원의 개발, 안정적인 공급과 효율적인 배분, 홍수재해방지 등을 위한 많은 노력을 해왔다. 최근에는 수자원의 관리효율화, 체계적 통합적으로 시행하고자 수자원법을 제정하여 수자원 관리의 체계를 개편하였으며, 향후 지자체 중심의 정량적인 물수급평가를 통해 현실적인 결과와 대안을 마련하는 것이 필요하다. 기존의 용수공급능력 평가와 물수급계획은 시 군 중심의 용수수요량을 바탕으로 중권역 단위로 확장하고, K-WEAP(Korea-Water Evaluation And Planing System) 모형을 활용하여 용수수급전망을 제시하고 있다. 이에 본 연구에서는 한강 권역을 중심으로 기존 계획에서 활용한 K-WEAP과 국내 외 활용도가 높은 MODSIM(Modified SIMYLD)을 활용하여 각 모형에 대한 입력자료, 내부 계산 알고리즘 및 분석방법 등 모형의 적용성을 검토하여 중권역 기반의 물수급 분석 결과를 비교 하였으며, 향후 모형 적용 시 고려사항 및 발생 가능한 오류를 최소화 할 수 있도록 하고자 하였다. 분석 결과, 기존 수자원장기종합계획에서 활용한 K-WEAP모형은 생 공 농업용수가 모두 동일우선순위이나, MODSIM모형에서는 수요지별 우선순위를 고려해야 하므로 상 하류간, 생활 공업, 농업으로 우선순위를 부여할 경우 물 부족량의 차이가 발생하였다. 우선순위 적용시 K-WEAP과 형과 MODSIM을 비교할 경우, 유사한 물부족량과 시점을 제공하고 있어 적용성과 분석결과의 일관성을 확인할 수 있었다. 또한 같은 물부족 결과를 제공하는 조건의 검토 수행 시간 측면과 모형구동 결과의 안정성에서 MODSIM이 더 우수한 것으로 분석되어 향후 지자체 중심의 세부적인 물수급평가를 위해서는 빠른 의사결정을 도울 수 있을 것으로 판단된다.

• Convergence Security Journal
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• v.18 no.2
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• pp.77-88
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• 2018

The purposes of this paper are to research the military utilization of weather modification techniques and to induce their research priority when considering the Korean Peninsular environment and technical level. To achieve these goals, the advantages and disadvantages of weather modification technologies have been discussed, and the evaluation index evaluation was derived through the Delphi method, and the weight of the evaluation index and the final research priority were induced through analytic hierarchical process. Analysis shows that the ionospheric modulation technology has the highest priority in terms of effectiveness as a weapon system and compatibility in the Korean Peninsula environment. It is expected that Korean ionosphere modification can disturb C4ISR function of the enemy and guarantee ours reliably when operating PGM, military satellite, surveillance & reconnaissance equipments, etc. Other weather modification technologies except for ionosphere modification should be developed gradually in that potential threat can be expanded to neighboring countries after the Unification of the Korea.