• Information Systems Review
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• v.8 no.1
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• pp.181-201
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• 2006

As the Internet spreads, many people have interests in e-CRM and product recommender systems, one of e-CRM applications. Among various approaches for recommendation, collaborative filtering and content-based approaches have been investigated and applied widely. Despite their popularity, traditional recommendation approaches have some limitations. They require at least one purchase transaction per user. In addition, they don't utilize much information such as demographic and specific personal profile information. This study suggests new hybrid recommendation model using two data mining techniques, association rule and classification, as well as intelligent agent to overcome these limitations. To validate the usefulness of the model, it was applied to the real case and the prototype web site was developed. We assessed the usefulness of the suggested recommendation model through online survey. The result of the survey showed that the information of the recommendation was generally useful to the survey participants.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.13 no.5
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• pp.484-491
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• 2002

This paper presents the results of a study of voltage-controlled PIN diode attenuators for Ku-band satellite payload and suggests the temperature-compensation method of these attenuators. The PIN diode attenuators are designed using thin-film hybrid techniques. The load resistance for maximum linear characteristics is determined by simulation and measurements. In the case of APD0805, load resistance of 150 $\Omega$ gives attenuator up to 10 dB linear attenuation range per a PIN diode. Also, measurements over temperature of these PIN diode attenuators were performed. From these measurements, designed PIN diode attenuators shows the severe temperature dependency due to forward voltage variation. A temperature compensation method using thermistor is now suggested to compensate the temperature variation of these PIN diode attenuators. This circuit shows good linear characteristics over wide temperature range

• Polymer(Korea)
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• v.34 no.2
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• pp.144-149
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• 2010

Ag/polystyrene(PS) nanocomposites were prepared by in situ reduction of silver 2-ethylhexylcarbamate (Ag-CB) complex and follwing radical polymerization only by heating at 110 $^{\circ}C$. In contrast to this conventional heating method, the microwave irradiation afforded well-dispersed silver nanoparticles(NPs) in styrene monomer without polymerization. The synthesis of Ag NPs proceeded uniformly throughout the reaction vessel only under microwave irradiation, completing the reaction simultaneously in the whole reaction solution. Successive polymerization of the monomer containing the resultant NPs has successfully produced a hybrid of the silver NPs dispersed in PS matrix. Ag/PS (0.1/100) nanocomposites were prepared successfully by melt-mixing process using Ag/PS(4.0/100) as a master-batch. UV-VIS spectroscopy, TEM, and X-ray diffraction techniques were used to investigate the process of formation of Ag/PS nanocomposites.

• The KIPS Transactions:PartA
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• v.14A no.7
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• pp.421-434
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• 2007

Among many other CG generated natural scenes, the representation of ocean surfaces is one of the most complicated and time-consuming problem because of its large extent and complex surface movement. We present a hybrid method to represent and animate unbound deep-water ocean surfaces by utilizing graphics processor as both simulation and rendering core. Our technique is mainly based on spectral approaches that generate a high-detailed height field using Fourier transform on a 2D regular grid. Additionally, we incorporate Gerstner model and generate low-detailed height field on a 2D projected grid in order to represent large waves and main structure of ocean surface. There is no interruption between CPU and GPU, and no need to transfer simulation results from the system memory to graphics hardware because the entire simulation and rending processes are done on graphics processor. As a result we can synthesize and render realistic water surfaces in real-time. Proposed techniques are readily adoptable to real-time applications such as computer games that have heavy work load on CPU but still demand plausible natural scenes.

• Korean Institute of Interior Design Journal
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• v.26 no.2
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• pp.101-109
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• 2017

The food and beverage spaces of modern industrial society have transformed from a simple space for meals into a space of culture, communication and experience as society becomes more complex and diverse along side economic growth. An interior designer who is rapidly rising on this flow of change is Yukio Hashimoto. While working for interior design firm Super Potato, which highlights food and beverage spaces, he was much affected by the expression methods of representative designer Takashi Sugimoto, who makes use of natural elements. By using these expression methods that make use of natural elements in his own creation of spatial ambience and elements of experience and by adding his own differentiated expression methods, he emphasizes an effective spatial expression for food and beverage spaces. The design characteristics of Yukio Hashimoto's food and beverage spaces are as follows. First natural elements like light and water are recreated as memories of nature after being established through a methodology that allows these elements to penetrate his own thoughts. Second, he pursues a hybrid design through the harmony between past tradition and current expressive techniques. Third, he expresses objets of light through a formative sense of shape expressed with light.. Fourth, he establishes an axis in the interior space by light and structure and endows a strong directionality that induces symmetric characteristics, gaze, and movement.. Fifth, he installs lights at the bottom of weighty materials and expresses a sense of floating by light. Sixth, he uses an illusion technique that makes use of the ambiguity and depth of space resulting from reflecting materials like mirrors. The study hopes that such design expression characteristics of food and beverage spaces can be used as data for interior designers to apply and develop a new design vocabulary.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.38 no.3
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• pp.269-274
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• 2014

In this study, low noise designs for a Savonius wind turbine were numerically investigated. As was reported in our previous study, the harmonic components with a fundamental frequency higher than the BPF were identified as being dominant in the noise spectrum of a Savonius wind turbine, and these components were a result of vortex shedding. On a basis of this observation, an S-shaped blade tip is proposed as a means of reducing the noise generated by small vertical(Savonius) wind turbines. This blade induces phase differences in the shedding vortices from the blades, and thus reduces the noise from the wind turbine. The aerodynamic noise characteristics of the conventional and "S-shaped" Savonius turbines were investigated by using the Hybrid CAA method where the flow field around the turbine is computed using the CFD techniques and the radiated noise are predicted by applying acoustic analogy to the computed flow field data. The degree of noise reduction resulting from the proposed design and its reduction mechanism were confirmed by comparing the predicted noise spectrum of these turbines and the flow characteristics around them.

• Journal of Korea Society of Industrial Information Systems
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• v.17 no.7
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• pp.139-148
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• 2012

An ensemble of classifiers is to employ a set of individually trained classifiers and combine their predictions. It has been found that in most cases the ensembles produce more accurate predictions than the base classifiers. Combining outputs from multiple classifiers, known as ensemble learning, is one of the standard and most important techniques for improving classification accuracy in machine learning. An ensemble of classifiers is efficient only if the individual classifiers make decisions as diverse as possible. Bagging is the most popular method of ensemble learning to generate a diverse set of classifiers. Diversity in bagging is obtained by using different training sets. The different training data subsets are randomly drawn with replacement from the entire training dataset. The random subspace method is an ensemble construction technique using different attribute subsets. In the random subspace, the training dataset is also modified as in bagging. However, this modification is performed in the feature space. Bagging and random subspace are quite well known and popular ensemble algorithms. However, few studies have dealt with the integration of bagging and random subspace using SVM Classifiers, though there is a great potential for useful applications in this area. The focus of this paper is to propose methods for improving SVM performance using hybrid ensemble strategy for bankruptcy prediction. This paper applies the proposed ensemble model to the bankruptcy prediction problem using a real data set from Korean companies.

• Journal of Microbiology and Biotechnology
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• v.13 no.6
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• pp.976-983
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• 2003

Seven Escherichia coli cells defective with aerobic growth were isolated by the insertion of ${\lambda}placMu53$, a hybrid bacteriophage of ${\lambda}$ and Mu, which created a transcriptional fusion to lacZY. These insertion mutant cells were tested on an XG ($5-bromo-4-chloro-3-indolyl-{\beta}-D-galactopyranoside$) medium for anaerobic expression of lacZ by fusion to a promoter. The chromosomal DNA from these strains were digested by EcoRI, and the EcoRI fragments that contained the fused gene and lacZ sequence were identified by Southern hybridization, using lacZ containing plasmid as a probe. The EcoRI fragment from each strain was cloned and sequenced. The sequence data were compared with the GenBank database. The mutated gene of three strains, CYT4, CYT5, and OS11, was found to be identical, and it was nrdAB that encoded ribonucleoside diphosphate reductase. The gene nrdAB was at min 50.5 on the Escherichia coli linkage map and 2,348,084 on the physical map, and is involved in hemAe-related reduction-oxidation reaction. OS6 and OS14 mutant strains had insertion at min 8.3 and the mutated gene was hemB. The hemB encodes 5-aminolevulinate dehydratase or porphobilinogen synthase. The OS3 mutant had insertion in cydB at min 16.6. The cydAB encodes cytochrome d oxidase. In the case of OS1, the fusion was made with sucA, the E1 component of ${\alpha}-ketoglutarate$ dehydrogenase.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.8
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• pp.1080-1089
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• 2013

Interior Permanent Magnet Synchronous Machines (IPMSMs) with rare earth magnet are widely used in electric vehicles and hybrid electric vehicles. IPMSMs having high efficiency, high torque, and a wide speed range are employed in propulsion system. And the rotor in an IPMSM is generally made of a rare earth magnet to achieve a large energy product and high torque. This paper discusses issues regarding design and performance of IPMSMs using different factors of BH magnetic characteristic. It is necessary to choose factors of magnetic material according to permanent magnet shape in rotor for high performance. Response Surface Methodology (RSM) is selected to obtain factors of magnetic material according to variety of rotor shapes. The RSM is a collection of mathematical and statistical techniques useful for the analysis of problems in which a response of interest in influenced by several variables and the objective is to optimize response. Therefore, it is necessary to analyze the torque characteristics of an IPMSM having magnet BH hysteresis curve with different rotor shape. Factors of residual flux density (Br) factor and intrinsic coercive force (Hc) are important parameters in RSM for rotor shape. The rotor shapes for IPMSMs having magnet BH characteristic were investigated using the RSM, and three shapes were analyzed in detail using FEA. The results lead to design consequence of IPMSMs in the various rare earth magnet materials.

• Journal of Microbiology and Biotechnology
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• v.11 no.6
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• pp.1115-1119
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• 2001

Eight Escherichia coli cells with aerobic growth deflects were isolated by the insertion of ${\lambda}placMu53$, a hybrid bacteriophage of ${\lambda}$ and Mu, which created transcriptional fusion to lacZY. Two of these mutants, CLIO and CLl2, were irradiated with UV to obtain specialized transducing phages. The phages that took out the neighboring chromosomal DNA of the related gene responsible for deflective aerobic growth were identified. The in vivo cloned chromosomal sequence revealed that the mutated gene of CLIO was located at min 34.5 on the Escherichia coli linkage map and 1,599,515 on the physical map. The physical map indicated that there were 7 cistrons in the operon. We named this operon oxg10. The promoter sequence of oxg10 exhibited a possible binding site far SoxS, a transcriptional regulator that activates the transcription of various SoxRS regulon genes. Transferring the oxg10:: ${\lambda}placMu53$ mutation into the wild-type strain, RZ4500, resulted in the inhibition of normal aerobic growth, while the salute mutation in strain MO inhibited aerobic cell growth completely. The full operon sequences of oxg10 were cloned from the Excherichia coli genomic library. The mutated gene of CLl2 was identified to be a sucA gene encoding the ${\alpha}$-ketoglutarate dehydrogenase El component in the TCA cycle.