• Journal of the Korean Mathematical Society
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• v.57 no.5
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• pp.1267-1286
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• 2020

We pay attention to a coupled problem by a penalty term which is induced from non-overlapping domain decomposition methods based on augmented Lagrangian methodology. The coupled problem is composed by two parts mainly; one is a problem associated with local problems in non-overlapping subdomains and the other is a coupled part over all subdomains due to the penalty term. For the speedup of iterative solvers for the coupled problem, we propose two different types of preconditioners: a block-diagonal preconditioner and an additive Schwarz preconditioner as overlapping domain decomposition methods. We analyze the coupled problem and the preconditioned problems in terms of their condition numbers. Finally we present numerical results which show the performance of the proposed methods.

• Architectural research
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• v.11 no.2
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• pp.43-49
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• 2009

Since the late 1980s, the schedule technique applied to the construction industry around the world has rapidly changed from the traditional ADM (Arrow Diagramming Method) to the PDM (Precedence Diagramming Method) technique. The main reason for this change is to overcome the limits and inconveniences of the traditional ADM technique. The time-cost trade-off is one of the core scheduling techniques to establish the best optimized combination plan in terms of a relationship between the cost and schedule. However, most of the schedule-related textbooks and research papers have discussed and proposed applications of a time-cost trade-off technique based only on the Finish to Start relationship. Therefore, there are almost no consideration and discussion of problems or restrictions that emerge when the time-cost trade-off technique is applied to the PDM network that has overlapping relationships. This paper proposes the lead-time adjustment method as a methodology for overcoming some restrictions that are encountered when the time-cost trade-off technique is applied to the overlapping relationships of the PDM network.

• Journal of Communications and Networks
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• v.7 no.4
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• pp.462-470
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• 2005

We propose a multi-rate and multi-BEP transmission scheme using adaptive overlapping pulse-position modulator (OPPM) and optical power controller in optical code division multiple access (CDMA) networks. The proposed system achieves the multi-rate and multi-BEP transmission by accommodating users with different values of OPPM parameter and transmitted power in the same network. The proposed scheme has advantages that the system is not required to change the code length and number of weight depending on the required bit rate of a user and the difference of bit rates does not have so much effect on the bit error probabilities (BEPs). Moreover, the difference of transmitted powers does not cause the change of bit rate. We analyze the BEPs of the four multimedia service classes corresponding to the com­binations of high/low-rates and low/high-BEPs and show that the proposed scheme can easily achieve distinct differentiation of the service classes with the simple system configuration.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.7
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• pp.3413-3430
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• 2017

With the fast increasing popularity of mobile services, ubiquitous mobile devices with enhanced sensing capabilities collect and share local information towards a common goal. The recent Mobile Crowd Sensing (MCS) paradigm enables a broad range of mobile applications and undoubtedly revolutionizes many sectors of our life. A critical challenge for the MCS paradigm is to induce mobile devices to be workers providing sensing services. In this study, we examine the problem of sensing task assignment to maximize the overall performance in MCS system while ensuring reciprocal advantages among mobile devices. Based on the overlapping coalition game model, we propose a novel workload determination scheme for each individual device. The proposed scheme can effectively decompose the complex optimization problem and obtains an effective solution using the interactive learning process. Finally, we have conducted extensive simulations, and the results demonstrate that the proposed scheme achieves a fair tradeoff solution between the MCS performance and the profit of individual devices.

• Transactions of Materials Processing
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• v.17 no.3
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• pp.203-209
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• 2008

In this paper, experimental investigation has been performed to analyze the forming process of toothed or serrated sheets, which is used as strap engaging surface of the seal to secure together overlapping portions of steel or plastic strapping ligature. Serration formed on the strap engaging surface of the seal prevent from relative slipping between overlapping ligatures after closing the seal. The geometry of tooth on the strap engaging surface is directly related to the quality of securing overlapping ligatures together. Inclined indentation followed by scratching operation has been proposed and applied to the experiments. Punch entry and face angles are selected as process variables to see the influence of these variables on the tooth geometry. Five different punch entry angles have been applied to experiments and three different punch face angles have been selected for each case of punch entry angle. Clay is selected as model material for experiments. Experimental results are summarized in terms of tooth height, tooth width, and aspect ratio such as tooth height to width ratio, respectively.

• Journal of Physiology & Pathology in Korean Medicine
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• v.24 no.2
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• pp.197-205
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• 2010

The association between five limpness(五軟), five stiffness(五硬), five retardation and disease have been repeatedly shown in patient. However, comparative study has been rare. This study arrange disease, which answer to five limpness, five stiffness, five retardation and classify by epiologic diagnosis. We search for scientific journals, medical college texts, theses of a degree and collect case reports. In this study we found that the five retardation(N=56) is showing numerous more than the others. The five stiffness(N=14) is showing rare than the five limpness(N=29). The five limpness is overlapping more than 90% with five retardation. and the five stiffness is overlapping 80% with five retardation. Symptom of five limpness, five stiffness, five retardation is coming out independent and overlapping each others. And generally it accompanies with abnormality in central nervous system.

• Journal of the Korea Society for Simulation
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• v.13 no.4
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• pp.31-42
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• 2004

GDS (Grating automatic Drawing System), which is an automatic design system of a metal product called grating, is a system that produces various detailed drawings on the basis of information within a Plan Drawing that represents layout of the grating such as locations, shapes, directions, etc. However, automatically produced drawings by GDS do not fully satisfy the standard of the general dimension marking method used among the layout designers. The lack of this standard quality mainly results from the fact that overlapping among dimension markings appear frequently. To solve the overlapping problem we applied the rule-based expert system. The rules are designed based on the expertise of skilled layout designers within the grating production lines.

• Journal of Electrical Engineering and Technology
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• v.7 no.3
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• pp.436-442
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• 2012

This paper develops a design methodology of a decentralized fuzzy load-frequency controller for a large-scale nonlinear power system with valve position limits on governors. The concerned system is locally exactly modeled in Takagi-Sugeno's form. Sufficient design condition for uniform ultimate boundedness of the closed-loop system is derived based on the overlapping decomposition. Convergence of all incremental frequency deviations to zero is also investigated. A simulation result is provided to visualize the effectiveness of the proposed technique.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.28B no.10
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• pp.755-760
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• 1991

In this paper, we propose a new formant locus overlapping method which can effectively enhance a naturalness of synthetic speech produced by ddemisyllable based Korean text-to-speech system. At first, Korean demisyllables are divided into several number of segments which have linear formant transition characteristics. Then, database, which is composed of start point and length of each formant segments, is provided. When we synthesize speech with these demisyllable database, we concatenate each formant locus by using a proposed overlapping method which can closely simulate haman articulation mechanism. We have implemented a Korean text-to-speech system by using this method and proved that the formant loci of synthetic speech are similar to those of the natural speech. Finally, we could illustrate that the resulting spectrograms of proposed method are more similar to natural speech than those of conventional method.

• Proceedings of the Korean Information Science Society Conference
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• 2005.07b
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• pp.769-771
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• 2005

In this paper we present a method of separating musical instrument sound sources from their monaural mixture, where we take the harmonic structure of music into account and use the sparseness and the overlapping NMF [1] to select representative spectral basis vectors which are used to reconstruct unmixed sound. A method of spectral basis selection is illustrated and experimental results with monaural mixture of voice/cello and trumpet/viola are shown to confirm the validity of our proposed method.