• KSII Transactions on Internet and Information Systems (TIIS)
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• 제9권4호
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• pp.1337-1358
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• 2015

In this paper, we present an analytical and simulated study on the performance of adaptive vehicular ad hoc networks (VANET) priority based on Transmission Distance Reliability Range (TDRR) and data type. VANET topology changes rapidly due to its inherent nature of high mobility nodes and unpredictable environments. Therefore, nodes in VANET must be able to adapt to the ever changing environment and optimize parameters to enhance performance. However, there is a lack of adaptability in the current VANET scheme. Existing VANET IEEE802.11p's Enhanced Distributed Channel Access; EDCA assigns priority solely based on data type. In this paper, we propose a new priority scheme which utilizes Markov model to perform TDRR prediction and assign priorities based on the proposed Markov TDRR Prediction with Enhanced Priority VANET Scheme (MarPVS). Subsequently, we performed an analytical study on MarPVS performance modeling. In particular, considering five different priority levels defined in MarPVS, we derived the probability of successful transmission, the number of low priority messages in back off process and concurrent low priority transmission. Finally, the results are used to derive the average transmission delay for data types defined in MarPVS. Numerical results are provided along with simulation results which confirm the accuracy of the proposed analysis. Simulation results demonstrate that the proposed MarPVS results in lower transmission latency and higher packet success rate in comparison with the default IEEE802.11p scheme and greedy scheduler scheme.

• 대한임베디드공학회논문지
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• 제2권4호
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• pp.260-273
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• 2007

The wireless sensor network (WSN) nodes are required to operate for several months with the limited system resource such as memory and power. The hardware platform of WSN has 128Kbyte program memory and 8Kbytes data memory. Also, WSN node is required to operate for several months with the two AA size batteries. The MAC, Network protocol, and small application must be operated in this WSN platform. We look around the problem of memory and power for WSN requirements. Then, we propose a new computing model of system software for WSN node. It is the Atomic Object Model (AOM) with Dual Priority Scheduling. For the verification of model, we design and implement IEEE 802.15.4 MAC protocol with the proposed model.

• 한국농공학회논문집
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• 제49권4호
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• pp.73-79
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• 2007

In the evaluation of rural amenity, it is hard to estimate the worth of rural amenity as numerical values. To evaluate the worth of an abstract idea, information measure technique(IMT) can be used. In this research, rural amenity priority assessment model(RAPAM) was developed adapting IMT. To apply the developed model for assessment of rural amenity, an encyclopedia was used as information gathering and utilizing system(IGUS). The application result of the developed model which was compared with the result of survey have similar trend. $R^{2}$ is 0.8539, RMSE is 0.382 and the applicability of RAPAM was proved.

• 한국농공학회논문집
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• 제48권1호
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• pp.41-48
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• 2006

In the evaluation of rural amenities, its properties are related with social, cultural, and environmental elements. In this study, Information Measure Model (IMM) and Cultural Property Priority Assessment Model (CPPAM) were developed adapting information measure model with text based surveying data. To apply developed model not only general properties but also specific surveyed data, Specific Information Gathering and Utilizing System (SIGUS) was constructed using the data in Dusan World encyclopedia. IMM shows priorities of cultural property by information in national-designated cultural properties. And CPPAM applied in surveying data in 2004 by Rural Resources Development Institute.

• 한국농공학회논문집
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• 제54권5호
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• pp.57-67
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• 2012

This paper presents the Multi Criteria Decision Making (MCDM) to evaluate water resources plan for agricultural reservoir. Preference Ranking Organization METHod for Enrichment Evaluations (PROMETHEE) and Analytic Hierarchy Process (AHP) were used to estimate weight and priority of alternatives to find out the most reasonable and efficient way of water resources assessment. The 6 criteria that both decision maker and beneficiary are satisfied have been identified to secure agricultural water resources and then the priority of 10 subcriteria was set. An enhanced PROMETHEE-AHP model was used to perform pairwise comparison and find out the priority of each alternative because the existing decision making model have uncertainty and ambiguity. Comparison analysis of decision making models was carried out to find a way of suitable decision making and validity of PROMETHEE-AHP model was suggested.

• 한국건설관리학회논문집
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• 제18권2호
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• pp.108-116
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• 2017

국내 교량은 공용 연수의 증가로 인하여 추후 유지관리 비용이 상당히 증가 될 것으로 예상된다. 이에 대응하여 정부와 관련 부처는 한정된 예산을 효율적으로 분배하고, 유지관리 우선순위를 합리적으로 선정할 수 있는 방법 개발에 집중하고 있다. 본 연구는 위험도기반의 유지관리 우선순위 선정 모델을 개발하기 위하여 교량의 파손을 야기하는 일반적인 위험 인자 14개를 선정하고, AHP분석을 수행하여 중요 인자 5개를 선별하였다. 기존 문헌 고찰과 전문가 자문을 통하여 선정된 인자에 대한 평가 기준, 영향도 가중치 등을 도출하였고 이를 활용하여 엑셀시트 기반의 위험도기반 우선순위 선정 기초 모델을 제시하였다. 본 모델을 기존의 유지관리 우선순위 선정 방법과 병행하여 사용한다면 보다 합리적인 교량 유지관리 우선순위를 도출 할 수 있을 것이다.

• Industrial Engineering and Management Systems
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• 제7권1호
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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.

• 대한전자공학회논문지SP
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• 제44권5호
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• pp.54-63
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• 2007

본 논문은 영상 완성(image completion)을 위해 계층적으로 적용되는 새로운 에너지 최적화 방식을 제안한다. 영상 완성의 목적은 영상의 특정 영역이 지워진 상태에서, 그 지워진 부분을 나머지 부분과 시각적으로 어울리도록 완성시키는 기법을 말한다. 본 논문에서는 전역적 특징의 탐지, 주변 환경 변화에 대한 유연성, 계산비용의 감소, 영상 인페인팅과 같은 관련기법들로의 확장성 문제들을 다룰 수 있도록 마르코프 랜덤 필드(Markov Random Field)로 모델링 된 예제 기반 방식(exampler-based mehtod) 접근법을 택한다. 그리고 MRF에서의 에너지 최적화를 위해 BP 알고리즘(Belief Propagation Algorithm)의 변형인 우선순위 BP 알고리즘(Priority-Belief Propagation Algorithm)을 적용하였다. 본 논문에서 제안한 계층적 우선순위 BP 알고리즘(Hierarchical Priority-Belief Propagation Algorithm)은 MRF의 정점의 수를 줄이고 메시지를 계층적으로 전파한다. 이렇게 계층적 우선순위 BP 알고리즘을 영상 완성에 적용하여 여러 영상들에서 바람직한 결과를 얻었다.

• ETRI Journal
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• 제42권1호
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• pp.36-45
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• 2020

A priority-based data communication approach, developed by employing cognitive radio capacity for sensor nodes in a wireless terrestrial sensor network (TSN), has been proposed. Data sensed by a sensor node-an unlicensed user-were prioritized, taking sensed data importance into account. For data of equal priority, a first come first serve algorithm was used. Non-preemptive priority scheduling was adopted, in order not to interrupt any ongoing transmissions. Licensed users used a nonpersistent, slotted, carrier sense multiple access (CSMA) technique, while unlicensed sensor nodes used a nonpersistent CSMA technique for lossless data transmission, in an energy-restricted, TSN environment. Depending on the analytical model, the proposed wireless TSN environment was simulated using Riverbed software, and to analyze sensor network performance, delay, energy, and throughput parameters were examined. Evaluating the proposed approach showed that the average delay for sensed, high priority data was significantly reduced, indicating that maximum throughput had been achieved using wireless sensor nodes with cognitive radio capacity.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회 2000년도 추계학술대회 및 정기총회
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• pp.259-262
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• 2000

The Cross-impact Hierarchy Process (CHP), an extended model of the Analytic Hierarchy Process(AHP) which is linked to Cross Impact Analysis(CIA), is a powerful decision making tool to assist in the ranking of large number of dependent technological alternatives. In this paper, we will describe an application of the CHP to the aerospace industry. We here conducted a questionnaire survey for S company that is one of the representative aerospace companies in Korea. A questionnaire was designed to obtain both the priority with dependence (the CHP priority) and the priority with independence (the AHP priority) in order to compare the priority derived by each of two methods. The hierarchy in this case study is concerned with priority setting for R&D area to ensure dependent aerospace design technology of the company, The result shows that there exists the difference hard to neglect between the final priorities gained by two methods.