• Elastomers and Composites
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• v.35 no.2
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• pp.115-121
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• 2000

In comparison with thermosetting rubber, thermoplastic elastomer (TPE) has various advantages such as simple processing, short cycle time and recycling of scrap. These advantages can lead to development of the high value-added rubber products due to reduction of the waste material, manufacturing cost and the defected product. This article involves a dynamic vulcanization method for EPDM/polypropylene blend, and the manufacturing of a fixed glass weather-strip by glass insert molding method using the blend. In order to investigate mechanical properties of the product, tensile strength, elongation, hardness and specific gravity were measured. Also morphological study was carried out using SEM. Developments of an efficient system of production and automatic process by molding of TPE and glass simultaneously are expected.

• Nuclear Engineering and Technology
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• v.33 no.4
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• pp.355-364
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• 2001

In order to evaluate and finally optimize the vitrification condition for combustible dry active waste (DAW), dust and gas generation characteristics were investigated for PE, cellulose, and mixed waste Tests were conducted by varying the operation variables such as melter configuration, excess oxygen amount, and waste feeding rate. Results showed that dust generation characteristics were affected by the operation parameters and the melter＇s configuration is the dominant one. For all tested DAWs, dust generation was reduced by increasing the waste feeding rate and the excessive oxygen amount in the melter. Among waste types, dust amount was decreased by the order of mixed wastes, PE, and cellulose. Other parameters such as temperature variation and operation time have also affected the dust generation. The optimum condition for the DAW vitrification was determined as the melter＇s configuration equipped for minimizing the waste dispersion with 20 kg/h of waste feeding rate and 100% of excessive oxygen supply. CO gas concentration in the off-gas was immediately influenced by the combustion state in the melter, but showed similar trend as the dust generation. For the NOx production during the vitrification process, thermal NOx, which is generated from the Post Combustion Chamber (PCC), rather than fuel NOx was assumed to be dominant. The gas cleaning of efficiencies of the PCC, wet scrubber, and Selective Catalytic Reduction system (SCR) were found to be high enough to keep the concentration of pollutants (CO, NOx, SOx, HCI) in the stack below their relevant emission limits.

• KEPCO Journal on Electric Power and Energy
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• v.2 no.2
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• pp.187-192
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• 2016

Chemical utilization of $CO_2$ is recognized as the technology for the reduction of greenhouse gas as well as the use of carbon to resources. Although various chemicals are commercially produced, the innovative development is still necessary to utilize large quantity of $CO_2$. In this report, the current status of technology to preserve -CO-O- linkage into the molecules was introduced, particularly for the synthesis of dimethyl carbonate (DMC) and polyols, which are raw materials of polycarbonate and polyurethane, respectively. RIST developed the novel process for the DMC production via urea methanolysis and the new catalytic system for polyol synthesis. Because of high contents of $CO_2$ in both chemicals, it is expected that they are able to contribute for the reduction of greenhouse gas.

• The Korean Journal of Physiology and Pharmacology
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• v.11 no.5
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• pp.163-169
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• 2007

The neurotoxicity of amyloid $\beta(A\beta)$ is associated with an increased production of reactive oxygen species and apoptosis, and it has been implicated in the development of Alzheimer's disease. While(-)-epigallocatechin-3-gallate(EGCG) suppresses $A\beta$-induced apoptosis, the mechanisms underlying this process have yet to be completely clarified. This study was designed to investigate whether EGCG plays a neuroprotective role by activating cell survival system such as protein kinase C(PKC), extracellular-signal-related kinase(ERK), c-Jun N-terminal kinase(JNK), and anti-apoptotic and pro-apoptotic genes in SH-SY5Y human neuroblastoma cells. One ${\mu}M\;A{\beta}_{1-42}$ decreased cell viability, which was correlated with increased DNA fragmentation evidenced by DAPI staining. Pre-treatment of SH-SY5Y neuroblastoma cells with EGCG($1{\mu}M$) significantly attenuated $A{\beta}_{1-42}$-induced cytotoxicity. Potential cell signaling candidates involved in this neuroprotective effects were further examined. EGCG restored the reduced PKC, ERK, and JNK activities caused by $A{\beta}_{1-42}$ toxicity. In addition, gene expression analysis revealed that EGCG prevented both the $A{\beta}_{1-42}$-induced expression of a pro-apoptotic gene mRNA, Bad and Bax, and the decrease of an anti-apoptotic gene mRNA, Bcl-2 and Bcl-xl. These results suggest that the neuroprotective mechanism of EGCG against $A{\beta}_{1-42}$-induced apoptotic cell death includes stimulation of PKC, ERK, and JNK, and modulation of cell survival and death genes.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.41 no.2
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• pp.56-64
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• 2018

In recent years, imbalanced data is one of the most important and frequent issue for quality control in industrial field. As an example, defect rate has been drastically reduced thanks to highly developed technology and quality management, so that only few defective data can be obtained from production process. Therefore, quality classification should be performed under the condition that one class (defective dataset) is even smaller than the other class (good dataset). However, traditional multi-class classification methods are not appropriate to deal with such an imbalanced dataset, since they classify data from the difference between one class and the others that can hardly be found in imbalanced datasets. Thus, one-class classification that thoroughly learns patterns of target class is more suitable for imbalanced dataset since it only focuses on data in a target class. So far, several one-class classification methods such as one-class support vector machine, neural network and decision tree there have been suggested. One-class support vector machine and neural network can guarantee good classification rate, and decision tree can provide a set of rules that can be clearly interpreted. However, the classifiers obtained from the former two methods consist of complex mathematical functions and cannot be easily understood by users. In case of decision tree, the criterion for rule generation is ambiguous. Therefore, as an alternative, a new one-class classifier using hyper-rectangles was proposed, which performs precise classification compared to other methods and generates rules clearly understood by users as well. In this paper, we suggest an approach for improving the limitations of those previous one-class classification algorithms. Specifically, the suggested approach produces more improved one-class classifier using hyper-rectangles generated by using Gaussian function. The performance of the suggested algorithm is verified by a numerical experiment, which uses several datasets in UCI machine learning repository.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.43 no.3
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• pp.156-166
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• 2020

In this study, through an AHP (Analytic Hierarchy Process) analysis, the internal construction project was designed to analyze the factors affecting the performance of the project and provide suggestions on the quality of communication. To carry out this study, a selection factor was selected by referring to AHP theory and existing prior research. AHP technique was used to collect weights after analysis, examine and analyze gaps. In the interior construction project, the most important factor among the factors influencing the quality of communication to the project performance was communication interaction. Among the sub-factors, accuracy of exchange of information and timeliness of communication were shown in the order of importance. Looking at the results of comprehensive analysis of the first and second layers, the accuracy of information exchange among the elements of communication quality was found to be the number 1 in weight. The timeliness of communication, which is ranked second, and communication that takes place at an appropriate time can lead to efficiency in shortening the project execution period by eliminating unnecessary work. And, Among the factors that affect communication quality, it was analyzed that communication method is not an important factor when compared to other factors. This study shows that quality of communication influences the performance of interior construction projects and provides suggestions for improving communication quality. And it has been confirmed that managing communication quality can act as an important issue that can improve business performance in project execution and production of results.

• Journal of the Korean Society of Safety
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• v.14 no.1
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• pp.101-107
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• 1999

$TiO_2$ and $xTiO_2-ySiO_2$ system photocatalysts were developed by sol-gel method based on the change of production parameters, and their structure of crystallization and the specific surface area was measured. Considering the efficiency of the ethanol decomposition using the catalyst, the conclusion was made as follows: 1) By means of X-ray analysis of $TiO_2$ powder that is obtained from water and Titanium alkoxide with various molar ratios, it is shown that structure of crystallization is a dominating structure and, on the other hand, the crystallization of rutile also partly exists. The specific surface area is at its maximum value at R=6, which is the molar ratio of water vs. alkoxide, whereas its value goes down as the molar ratio increases. In the reaction of using $TiO_2$ catalyst, the ethanol is decomposed into the extent of 15 ~30% in an hour and three hours are necessitated for 70% decomposition. 2) $TiO_2/SiO_2$ powder is developed from Titanium and Silicon alkoxide by a hetero-condensation process. The increase of SiO$_2$ contents causes the decrease of the degree of crystallization of the gel, whereas the specific surface area preferentially increases. In the decomposition reaction of the ethanol, the decomposition efficiency represents 25~60% in an hour. It is, however, examined that the efficiency inactively increases corresponding to the duration of reaction time. It is shown that more than 90% of ethanol is decomposed when reaction time is about three hours and the efficiency illustrates the maximum value for 60-$TiO_2/4O-SiO_2$ catalyst.

• Korean Chemical Engineering Research
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• v.49 no.6
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• pp.739-744
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• 2011

Activated carbon SCR(CSCR) catalyst that is used to remove $NO_x$ in exhaust gas including boron discharged from the production process of liquid crystal display(LCD) shows deactivation when boron is deposited to block the pores within the catalyst or to cover its active sites. The spent carbon catalyst is regenerated by washing with various surfactants, drying and calcination. For comparison of the physical and chemical properties before and after the regeneration with the variables, type of surfactants and calcination condition, element analysis by ICP, $N_{2}$ adsorption were conducted. $DeNO_{x}$ in SCR with $NH_3$ was carried out in a fixed bed reactor at $120^{\circ}C$. The activated carbon catalyst regenerated through washing with a non-ionic surfactant in $H_{2}O$ at $90^{\circ}C$ and calcination under $N_{2}$ gas at $550^{\circ}C$ shows similar level of surface area and $NO_x$ removal efficiency with those of fresh catalyst.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.3 no.3
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• pp.17-65
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• 2008

The manager of manufacturing industry just not to have known to do related to the law of Product Liability that was put into operation in July 2002. The law of PL is a public law about defective product, which was established in order to compensate consumer's damages of property and body caused by product, to make sound society by the safety products and to take international competitiveness. The economic effects by the law of Product Liability are the increase of consumers relief production cost by the lawsuits. Product liability as a process has developed significantly in the United Kingdom and the United States of America. The rapid introduction of product liability has recently been a prevalent phenomenon, as global changes arising from rapid development in science and the economy have resulted in a highly interconnected world economy. This thesis was established, based on current literature and business consulting cases in the position of companies, and is one of the operating subjects in a system for legal responsibility in manufactured products. However, there are limitations in the fact that research theories are only able to present a theoretical model and directions. In this context, managers and personnel of multiple companies cannot adequately respond to the recently enforced Product Liability Act. The major findings are summarized as Product Liability Management Activity are positively Correlation of Enterprise Value.

• Journal of the Korea Society of Computer and Information
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• v.15 no.5
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• pp.1-11
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• 2010

The success of semantic web depends largely on the semantic annotation which systematizes knowledge for the construction and production of ontology. Therefore, the efficiency of semantic annotation is very important in order to change many knowledge expressions and generate into ontology instances. In this paper, we presents a generation system of rule-based ontology instances which are produced accurately and efficiently via semantic annotation in conventional web sites. In conventional studies, the manual process is necessary for finding relevant information, comparing it with ontology, and entering information. We propose a new method that manages keyword data regarding extracted information and rule information separately. Thus, it is quite practical to extract information efficiently from various web documents by adding a small number of keywords and rules. The proposed method shows the possibility of ontology instance generation which reuses the rules and keywords from the various websites.