• Journal of the Korean Society of Safety
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• v.31 no.4
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• pp.35-41
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• 2016

In order to guarantee the process safety and prevent accidents, the deviations from normal operating conditions should be monitored and their root causes have to be identified as soon as possible. The statistical theories-based method among various fault diagnosis methods has been gaining popularity, due to simplicity and quickness. However, according to fault magnitudes, the scalar value generated by statistical methods can be changed and this point can lead to produce wrong information. To solve this difficulty, this work employs PCA (Principal Component Analysis) based method with qualitative information. In the case study of our previous study, the number of assumed faults is much smaller than that of process variables. In the case study of this study, the number of predefined faults is 19, while that of process variables is 6. It means that a fault diagnosis becomes more difficult and it is really hard to isolate a single fault with a small number of variables. The PCA model is constructed under normal operation data in order to get a loading vector and the data set of assumed faulty conditions is applied with PCA model. The significant changes on PC (Principal Components) axes are monitored with CUSUM (Cumulative Sum Control Chart) and recorded to make the information, which can be used to identify the types of fault.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.64 no.1
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• pp.107-112
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• 2015

This paper introduces an evolutionary nonlinear regression based compensation technique for the short-range prediction of wind speed using AWS(Automatic Weather Station) data. Development of an efficient MOS(Model Output Statistics) is necessary to correct systematic errors of the model, but a linear regression based MOS is hard to manage an irregular nature of weather prediction. In order to solve the problem, a nonlinear and symbolic regression method using GP(Genetic Programming) is suggested for a development of MOS wind forecast guidance. Also FCM(Fuzzy C-Means) clustering is adopted to mitigate bias of wind speed data. The purpose of this study is to evaluate the accuracy of the estimation by a GP based nonlinear MOS for 3 days prediction of wind speed in South Korean regions. This method is then compared to the UM model and has shown superior results. Data for 2007-2009, 2011 is used for training, and 2012 is used for testing.

• Journal of the Korean Society of Costume
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• v.59 no.10
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• pp.38-50
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• 2009

Since Homeros in Greece, Mimesis was thought to be an art to imitate the nature, and it means an imitation of the nature classically. Mimetic theories were set to be a kind of art work in the era of Renaissance, and the terminology of mimesis was widely used to replace it with an originality in the 15th century. The purpose of this study is to understand the aesthetics of mimesis expressed in 2000s fashion. For this purpose, I investigated the theories of the mimesis, categorized the definition, then applied those categories for 2000s fashion. Documentary studies were conducted through aesthetics, fashion books and demonstrative studies were processed by analyzing photos from collection fashion magazines and fashion site of internet. In the history of aesthetics, the mimesis could be defined into three categories; the similarity and the representation mimesis, the symbol mimesis and the abstraction mimesis. In fashion, the representation mimesis included a natural and a folk, a period that of 1900s and ancient representation mimesis. The symbol mimesis included psychology and fear symbol mimesis. The abstraction mimesis included hard color, a geometric simplification and distortion mimesis. Analysis on the mimesis expressed in 2000s modern fashion may provide an excellent method for understanding human aesthetic in costume.

• Journal of Fashion Business
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• v.14 no.5
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• pp.112-127
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• 2010

Primitivism is a concept that expresses and organizes natural feelings of human beings which is hard to be identified by a rigid definition. It means "staying in the beginning or the initial state, not evolving or developing, and not affected by human beings from the intact natural state". Based on this meaning, the artistic style features inherent natural beauties, as well as plain and inornate design. These features have been reflected in a variety of art pieces. The aesthetic features shown in the primitivism art pieces can be categorized into four different aspects: naturalness, folksiness, sentimentality, and humorousness. These features, influencing modern fashion, have been reinvented by a number of fashion designers. They also adopted ideas from the fancy clothes and ornaments created in carefree life style of the regions retaining their primitive cultures, such as Africa, Oceania, and Pacific coasts, and applied those ideas to various silhouette, colors, patterns, and textiles. Particularly as for textile expressions, they tried printing techniques using the patterns motivated from primitive folk symbols or the nature, applied objet of primitive materials and elaborated ornaments that represent folk and primitive feelings, and employed the primitive techniques such as knotting, crude cutting, or natural draping, to reinvent them as textile expressions in modern fashion.

• Proceedings of the KIEE Conference
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• 2002.07d
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• pp.2821-2823
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• 2002

In this paper we propose the Multi-FNN (Fuzzy-Neural Networks) for optimal identification modeling of complex system. The proposed Multi-FNNs is based on a concept of FNNs and exploit linear inference being treated as generic inference mechanisms. In the networks learning, backpropagation(BP) algorithm of neural networks is used to updata the parameters of the network in order to control of nonlinear process with complexity and uncertainty of data, proposed model use a HCM(Hard C-Means)clustering algorithm which carry out the input-output dat a preprocessing function and Genetic Algorithm which carry out optimization of model The HCM clustering method is utilized to determine the structure of Multi-FNNs. The parameters of Multi-FNN model such as apexes of membership function, learning rates, and momentum coefficients are adjusted using genetic algorithms. An aggregate performance index with a weighting factor is proposed in order to achieve a sound balance between approximation and generalization abilities of the model. NOx emission process data of gas turbine power plant is simulated in order to confirm the efficiency and feasibility of the proposed approach in this paper.

• Journal of Communications and Networks
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• v.18 no.3
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• pp.493-501
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• 2016

In-network storage is an effective technique for avoiding network congestion and reducing power consumption in continuous data collection in wireless sensor networks. In recent years, network coding based storage design has been proposed as a means to achieving ubiquitous access that permits any query to be satisfied by a few random (nearby) storage nodes. To maintain data consistency in continuous data collection applications, the readings of a sensor over time must be sent to the same set of storage nodes. In this paper, we present an efficient approach to updating data at storage nodes to maintain data consistency at the storage nodes without decoding out the old data and re-encoding with new data. We studied a transmission strategy that identifies a set of storage nodes for each source sensor that minimizes the transmission cost and achieves ubiquitous access by transmitting sparsely using the sparse matrix theory. We demonstrate that the problem of minimizing the cost of transmission with coding is NP-hard. We present an approximation algorithm based on regarding every storage node with memory size B as B tiny nodes that can store only one packet. We analyzed the approximation ratio of the proposed approximation solution, and compared the performance of the proposed coding approach with other coding schemes presented in the literature. The simulation results confirm that significant performance improvement can be achieved with the proposed transmission strategy.

• The Journal of Korean Academy of Prosthodontics
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• v.46 no.4
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• pp.325-334
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• 2008

Statement of problem & Purpose: The purpose of this study was to investigate the effect of a mouth guard material properties on the skull and brain when they were under impact loads on mandible. Material and methods: Two customized mouth protectors having different material propeerst ieach other were made for a female Korean who had no history of brain trauma, no cerebral diseases, nomal occlusion and natural dentition. The 3D finite element model of human skull and brain scanned by means of computed tomography was constructed. The FEM model of head was composed of 407,825 elements and 82,138 nodes, including skull, brain, maxilla, mandible, articular disc, teeth and mouth guard. The stress concentrations on maxillary teeth, maxilla and skull with two mouth guards were evaluated under oblique impact load of 800N onto mandibular 3 loading points for 0.1sec. And the brain relative displacement was compared in two different mouth guard materials under same condition. Result and Conclusion: The results were as follows; 1. In comparison of von Mises stress on maxillary teeth, a soft mouth guard material had significantly lower stress values on measuring point than a hard mouth protector materials (P < .05). 2. In comparison of von Mises stress on maxilla and skull, A soft mouth protector material had significantly lower stress values on measuring point than a hard mouth protector materials (P < .05). 3. For impact loads on mandible, there were more stress concentrated area on maxilla and skull with hard mouth guard than soft with mouth protector. 4. For impact loads on mandible, brain relative displacement had little relation with mouth guard material properties. In results of this study, soft mouth guard materials were superior to hard mouth guard materials for mandible impact loads for prevention of sports injuries. Although the results of this study were not enough to figure out the roles of needed mouth guard material properties for a human head, we got some knowledge of the pattern about stress concentration and distribution on maxilla and skull for impact loads with soft or hard mouth protector. More studies are needed to substantiate the relationship between the mouth guard materials and sports injuries.

• Journal of the korean academy of Pediatric Dentistry
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• v.31 no.2
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• pp.228-235
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• 2004

The development and proliferation of the mandibular condyle can be altered by changes in the biomechanical environment of the temporomandibular joint. The biomechanical loads were varied by feeding diets of different consistencies. The purpose of the present study was to determine whether changes of masticatory forces by feeding a soft diet can alter the trabecular bone morphology of the growing mouse mandibular condyle, by means of micro-computed tomography. Thirty-six female, 21 days old, C57BL/6 mice were randomly divided into two groups. Mice in the hard-diet control group were fed standard hard rodent pellets for 8 weeks. The soft-diet group mice were given soft ground diets for 8 weeks and their lower incisors were shortened by cutting with a wire cutter twice a week to reduce incision. After 8 weeks all animals were killed after they were weighed. Following sacrifice, the right mandibular condyle was removed. High spatial resolution tomography was done with a Skyscan Micro-CT 1072. Cross-sections were scanned and three-dimensional images were reconstructed from 2D sections. Morphometric and nonmetric parameters such as bone volume(BV), bone surface(BS), total volume(TV), bone volume fraction(BV/TV), surface to volume ratio(BS/BV), trabecular thickness(Tb. Th.), structure model index(SMI) and degree of anisotropy(DA) were directly determined by means of the software package at the micro-CT system. From directly determined indices the trabecular number(Tb. N.) and trabecular separation(Tb. Sp.) were calculated according to parallel plate model of Parfitt et al.. After micro-tomographic imaging, the samples were decalcified, dehydrated, embedded and sectioned for histological observation. The results were as follow: 1. The bone volume fraction, trabecular thickness(Tb. Th.) and trabecular number(Tb. N.) were significantly decreased in the soft-diet group compared with that of the control group (p<0.05). 2. The trabecular separation(Tb. Sp.) was significantly increased in the soft-diet group(p<0.05). 3. There was no significant differences in the surface to volume ratio(BS/BV), structure model index(SMI) and degree of anisotropy(DA) between the soft-diet group and hard-diet control group (p>0.05). 4. Histological sections showed that the thickness of the proliferative layer and total cartilage thickness were significantly reduced in the soft-diet group.

• The Journal of the Korean Society for Microbiology
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• v.9 no.1
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• pp.25-31
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• 1974

A comparative study was performed with 176 cultures of Salmonella organisms on tetracyline, neomycin and colistin in order to find out the relationship between the results obtained from the Ericsson's single disk method and the tube dilution method of antibiotic sensitivity tests which may be carried out in many hospital laboratories. With tetracycline, thirty-three out of 163 cultures of Salmonella typhi were found to be either sensitive or moderate sensitive by means of the disk method and thirty one(ca 94%) out of the thirty three cultures showed less than 1.0 ${\mu}g$ of the Minimal Inhibitory Concentretions(MIC) in the tube-dilution tests, which mean that there were a quite good agreement between the two methods. With neomycin, a hundred and five out of 163 S.typhi were appeared to be either sensitive or moderate sensitive by means of Ericsson's single disk method, among which 103 cultures showed less than 10.0 ${\mu}g$ MIC in the tubedilution method. And also there was a quite correlative pat. terns observed in the result of testing with 13 salmonella cultures other than S. typhi. With colistin, it was hard to observe any particular tendency in the distribution of plotting for 148 cultures showing less the 18 mm in the inhibiting zone diameters between MIC and disk sensitivity patterns except the fifteen, cultures out of 176 salmonella, which appeared to be sensitive in the single disk method and showed less than 1.0 ${\mu}g$ MIC in the tube dilution method.

• Journal of Digital Convergence
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• v.18 no.11
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• pp.247-257
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• 2020

The Purpose of this study is to present effective Anti-Drone systems to protect national important facilities against drones that are illegally used by crime groups and terrorists with malicious intents. In order to accomplish the purpose of the study, technical and policy reports regarding Anti-Drone systems, open documents from manufacturers and various research papers are reviewed, and in-depth interviews with experts were conducted. Studies have shown that it is effective to overlay and mix different detection systems so that they can improve detection rates by supplementing each other's advantages and disadvantages, and that the means of incapacitation need to acquire flexibility by using both soft-kill and hard-kill methods in accordance with operational environment for the effective usage. In other words, the establishment of an illegal drone pre-management system, mixed and overlapping detection assets, determining appropriate countermeasures, and multiple distribution of means of incapacitation. The establishment of a protection system for important national facilities through the operation of overlapping and complex anti-drone systems is the most urgent task.