• Journal of Korea Multimedia Society
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• v.9 no.7
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• pp.854-863
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• 2006

As WiBro service providers which provide a wireless multimedia communication service are selected, the commercial service will emerge in the near future. Although the use of efficient multicast technology for multimedia will be essentially required, it would be difficult to design the overall communication network in the early stage by using IP multicast due to technological or commercial issues. Application layer multicast schemes or hybrid multicast schemes also should be considered. In this paper, we propose a hybrid multicast scheme and evaluate its performance against typical IP multicast schemes on modelling of the WiBro network for one of WiBro service providers. We also propose a simulation method for the hybrid multicast on the simulation network for performance evaluation. If the number of mobile nodes reaches a certain point, the performance difference between the hybrid multicast and IP multicast is reduced significantly. We show that hybrid multicast technology can be applied for WiBro service without much performance degradation.

• Journal of Korea Water Resources Association
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• v.55 no.spc1
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• pp.1271-1282
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• 2022

The optimal design of Water Distribution System (WDS) is used in various ways according to the purpose set by the user. The optimal design of WDS has various purposes, such as minimizing costs and minimizing energy generated when manufacturing pipes. In this study, based on the Modified Hybrid Vision Correction Algorithm (MHVCA), a cost-optimal design was conducted for various WDSs. We also propose a new evaluation index, Best Rate (BR). BR is an evaluation index developed based on the K-mean Clustering Algorithm. Through BR, a comparison was made on the possibility of searching for the optimal design of each algorithm used in the optimal design of WDS. The results of MHVCA for WDS were compared with Vision Correction Algorithm (VCA) and Hybrid Vision Correction Algorithm (HVCA). MHVCA showed a lower cost design than VCA and HVCA. In addition, MHVCA showed better probability of lower cost designs than VCA and HVCA. MHVCA will be able to show good results when applied to the optimal design of WDS for various purposes as well as the optimal design of WDS for cost minimization applied in this study.

• Journal of Institute of Control, Robotics and Systems
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• v.6 no.2
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• pp.197-206
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• 2000

A hybrid control structure for vision-based soccer robot system is considered. The structure is om-posed of four levels such as the role action behavior and execution levels. The control structure which is a combination of hierarchical and behavioral structures can efficiently meet the behavior and design specifications of a soccer robot system Among the four levels only the design of the action level is proposed in the paper and is experimentally evaluated. Design hypothesis and evaluation method are presented to improve the reliability and accomplishment of the robot system. Due to the essential element of soccer robot system design a systematic design procedure of the action level is proposed With the proposed structure and algorithm of the action level the excellent result was shown at the MiroSot'98 held in France.

• Journal of Electrical Engineering and Technology
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• v.13 no.4
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• pp.1407-1418
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• 2018

Novel mechanism of customized adequacy formulation is proposed in order to enhance micro grids system reliability. The mechanism accounts for 2-levles of load curtailment, and is mainly based on probabilistic load profile and hybrid Distributed Generation (DG) units modeling. The two load curtailments are needed in order to ensure adequate technical constraints at steady state condition during islanding mode of operation. The effectiveness of the proposed formulation has been verified using system independent analytical expressions for the evaluation of both reliability and Expected Energy Not Served (EENS) indices. The evaluation has examined the impact of different penetration levels of Hybrid DG Units in case study islands. Results show the enhancement of the overall distribution system reliability and the recommended conditions for successful islanding mode of operation.

• Proceedings of the Korean Information Science Society Conference
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• 2002.04a
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• pp.193-195
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• 2002

본 논문에서는 최근에 제안된 Hybrid 방식의 모바일 멀티캐스트 프로토콜 중 MOM, MMA, RBMOM, 그리고 TBMOM 프로토콜에 대해서 여러 가지 관점에서 성능을 비교하여 각 프로토콜의 장단점을 분석함과 동시에, 이들 방식이 공통적으로 가지는 DMSP(Designated Multicast Service Provider) 핸드오프 문제에 대해서 Smooth DMSP 핸드오프방식을 제안한다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.05a
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• pp.663-664
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• 2010

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2009.06a
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• pp.985-986
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• 2009

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2011.05a
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• pp.87-88
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• 2011

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.12 no.3
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• pp.83-88
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• 1998

This paper presents an overview of environmental evaluation for a photovoltaic-fuel cell hybrid power plant through the Ideal Point approach, which is one of multiobjective decision support systems. Its evaluation is carried out in terms of such tow criteria as land requirement for plant construction and lifetime CO2 emissions, and ten compared with conventional fossil fuel power plants. Fuel cell power system has been proven a viable technology to back up severe PV power fluctuations under inclement weather conditions. Fuel cell power generation, containing small land use, is able to alleviate the heavy burden of large surface requirement of PV power plants. In addition, the PV-fuel cell hybrid power system shows a very little potential for lifetime CO2 emissions.

• Proceedings of the Technology Innovation Conference
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• 1999.06a
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• pp.245-265
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• 1999

MAUT and AHP are widely used for quantification of subjective judgements in various fields of decision making. This study focuses on the introduction and application of MAUT/AHP method which is a hybrid of MAUT and AHP techniques in R&D project priority setting. This hybrid model can clarify each factors' contribution using MAUT method and can reduce the number of pairwise comparisons of AHP method. This study applies AMUT/AHP method to the evaluation of R&D projects in a Government - funded research institute. To evaluate R&D projects, six evaluation factors are derived. SMART(Simple MultiAttribute Rating Technique) and DVM(Difference Value Measurement ) out of many MAUT methods are used to design the utility function ad AHP is used to allocate the weights among evaluation factors. The major findings of this study can be summarized as follows. First, the SMART/AHP and the DVM/AHP have the same results with the SMART and the DVM, and they are different results with AHP. It is very hard to decide which one is better. Second, MAUT/AHP's strength is analyzed. MAUT reflects utility values of evaluators to alternatives and AHP results objective and consistent weights of factors through pariwise comparisons. Third, its possible application fields are proposed. It is applicable to subjective decision making problems with high complexity and inter-independent factors.