• International Journal of Contents
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• v.9 no.1
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• pp.1-5
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• 2013

Standard Gaussian Mixture Model (GMM) is a well-known method for image segmentation. However, one of its problems is that we consider the pixel as independent to each other, which can cause the segmentation results sensitive to noise. It explains why some of existing algorithms still cannot segment texts from the background clearly. Therefore, we present a new method in which we incorporate the spatial relationship between a pixel and its neighbors inside $3{\times}3$ windows to segment the text. Our approach works well with images containing texts, which has different sizes, shapes or colors in case of light changes or complex background. Experimental results demonstrate the robustness, accuracy and effectiveness of the proposed model in image segmentation compared to other methods.

• Journal of Korea Multimedia Society
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• v.20 no.6
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• pp.865-872
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• 2017

Recent advance in electronics and scintillators makes it possible to utilize the time-of-flight (TOF) information in improving image reconstruction of positron emission tomography(PET). In this paper, we propose a TOF-based fast image reconstruction method for PET. The proposed method uses the deconvolution of TOF data for each angle view and the rotational averaging of deconvolved images. Simulation results show an improved performance of the proposed method, as compared with filtered backprojection (FBP) method, TOF-FBP, and TOF version of expectation-maximization(EM) methods. Simulation results also show a great potentiality of the proposed method in limited angle tomography applications.

• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.110.1-110
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• 2002

We propose a novel neuro-fuzzy system based on an efficient clustering method. It is a very useful method that improves the performance of a fuzzy model with small number of fuzzy rules. The fuzzy clustering methods are studied in the wide range of fuzzy modeling. One of them, the grid partition method has problem of exponentially increasing number of rules when the dimension of input or number of membership function is linearly increased. On the other hand, the Expectation Maximization algorithm is an efficient estimation for unknown parameters of the Gaussian mixture model. Here it is noted that the parameters can be used for fuzzy clustering method. In a fuzzy modeling, it is desired that...

• Journal of Korean Society of Transportation
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• v.5 no.1
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• pp.47-58
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• 1987

A commodity distribution problem with intertemporal storage facilities and dynamic transportation networks is proposed. mathematical integer programming methods and multiobjective programming techniques are used in the model formulation. Dynamic characteristics of commodity distribution problems are taken into account in the model formulation. storage facility location problems and transportation link addition problems are incorporated into the intertemporal multicommodity distribution problem. The model is capable of generating the most efficient and rational commodity distribution system. Therefore it can be utilized to provided the most effective investment plan for the transportation infrastructure development as well as to evaluate the existing commodity distribution system. The model determines simultaneously the most efficient locations, sizes, and activity levels of storage facilities as well as new highway links. It is extended to multiobjective planning situations for the purpose of generating alternative investment plans in accordance to planning situations. sine the investment in transportation network improvement yields w\several external benefits for a regional economy, the induced benefit maximization objective is incorporated into the cost minimization objective. The multiobjective model generates explicitly the trade-off between cost savings and induced benefits of the investment in transportation network improvement.

• Journal of computational fluids engineering
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• v.11 no.1 s.32
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• pp.21-28
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• 2006

Reliability Based Design Optimization(RBDO) is one of the optimization methods that minimize the product failure due to small changes of operating conditions or process errors. It searches the optimum that satisfies the safety margin of each constraint, and it gives stable and reliable designs. However, RBDO requires many times oj computational efforts compared with the conventional deterministic optimization(DO) to evaluate the probability of failure about each constraint, therefore it is hard to apply directly to large-scaled problems such as a flexible wing shape design optimization. For the efficient reliability analysis, the approximate reliability analysis method with the two-point approximation(TPA) is proposed In this study, the lift-to-drag ratio maximization designs are performed with 3-dimensional Navier-Stokes analysis and NASTRAN structural analysis, and the optimization results about the deterministic, FORM and SORM are compared.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.4
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• pp.573-586
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• 2011

Along with the recent changes in animal feed supply circumstances, many enzyme and probiotic feed supplements have been introduced and applied to pigs and chicken diets. Therefore, both selection of the appropriate feed supplements and their proper supplementation becomes critical to justify the supplementation. Meta-analysis was proposed as an appropriate tool to assess the large amount of relevant information. In this review, reliable data from recent publications was compounded then analyzed to determine the best practice of effective enzyme supplementation from the perspectives of animal species, age, characteristics of feed, target substrates, optimum multi enzymes combination and intended objectives. The results of the analysis suggested pratical methods of probiotic supplementation regarding intestinal microbiota, physiological limitation of probiotics, maximization of the probiotic benefit and synergism with prebiotic supplements.

• Proceedings of the Korean Society of Toxicology Conference
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• 2001.10a
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• pp.194-194
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• 2001

Preclinical test methods for allergenic potential chemicals has been widely used to assess human risks and has been developed. Recently, the murine local lymph node assay (LLNA) has been proposed as a prospective method to identify contact allergens and to replace conventional the guinea pig maximization test (GPMT). The objective of this study was to establish LLNA and to evaluate allergenicity of chemicals by LLNA. (omitted)

• Journal of the Korea Safety Management & Science
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• v.7 no.3
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• pp.121-135
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• 2005

The TOC and Six Sigma are the most attention-getting concepts for managing manufacturing companies. Using the ideas and methods of the TOC, companies can achieve a large reduction of work-in-process and finished good inventories, significant improvement in scheduling performance, and substantial earnings increase. The six sigma approach derives the overall process of selecting the right project based on their potential to improve performance metrics and selecting and training the right people to get the business results. These two concepts have different backgrounds and different viewpoints for production systems. so, if the two concepts integrate each other, the synergy effects to innovate production systems can be expected. The purpose of this paper suggest that integration strategy between Six Sigma and TOC for profit maximization.

• Proceedings of the KSR Conference
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• 2003.05a
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• pp.185-189
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• 2003

According to opening Seoul-Busan high speed rail line in 2004, we are studying to offer speedily for the parcel service of high speed rail-combined transport as it does, tender the quality freight services within a one and the same high speed train formation. Therefore, we reviewed for various types of HSR-combined transport and suggested to application methods in Korean high speed rail line. Through these kinds of approaches, we are able to expect the fulfillment of customer needs for high speed rail market segments, the profit maximization of future railway operating companies, and enhancement for cost-effective rail network operation of the mixed traffic on infrastructure cost-reduction in national logistics.

• Water for future
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• v.13 no.3
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• pp.77-81
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• 1980

Probable Maximum Precipitation values for seven heavy stroms during the period from 1966 to 1976 are derived, using the manual for W.M.O P.M.P analysis of strom precipitation. The hydrometeoroogical and the statistical methods are consisted of the procedure of P.M.P. estimation in this study. It is possible to draw P.M.P curves from the view points of area and strom durations. A comparison has been made between the P.M.P values of Nakding River basin and the results of this paper. For a storm period of 24 hours, the P.M.P value at the maximum station is 762 mm and the moistrue maximization ratio are within the range 1.17 to 1.41 for the seven selected stroms.