• Journal of the Computational Structural Engineering Institute of Korea
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• v.21 no.5
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• pp.413-419
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• 2008

Deterministic design optimization (DO) does not explicitly deal with a variety of factors from inherent randomness and uncertainties. Reliability based design optimization(RBDO) is necessary to use in engineering systems in order to guarantee quality and performance of product. In this paper, design variables are considered as random variables. Standard deviation according to change of design variables have changed as much as coefficient of variation. And, if the standard deviation is error of manufacturing, standard deviation-mean relation is concave form. We obtain reliability index using advanced first order second moment method(AFOSM). This paper is examined by solving two examples and the results are compares with DO, RBDO and suggested RBDO.

• Journal of Convergence for Information Technology
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• v.8 no.2
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• pp.233-238
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• 2018

SMEs and small enterprises are making various attempts to manage SMEs in terms of equipment, safety and energy management as well as production management. However, SMEs do not have the investment capacity and it is not easy to build a smart factory to improve management and productivity of SMEs. In this paper, we propose a smart factory construction algorithm that partially integrates the factory equipment currently operated by SMEs. The proposed algorithm supports collection, storage, management and processing of product information and release information through IoT device during the whole manufacturing process so that SMEs' smart factory environment can be constructed and operated in stages. In addition, the proposed algorithm is characterized in that central server manages authentication information between devices to automate the linkage between IoT devices regardless of the number of IoT devices. As a result of the performance evaluation, the proposed algorithm obtained 13.7% improvement in the factory process and efficiency before building the Smart Factory environment, and 19.8% improvement in the processing time in the factory. Also, the cost of input of manpower into process process was reduced by 37.1%.

• Journal of Institute of Control, Robotics and Systems
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• v.22 no.4
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• pp.276-280
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• 2016

Due to the increasing interest in safety and consistent product quality over a past few decades, demand for effective quality monitoring and safe operation in the modern industry has propelled research into statistical based fault detection and diagnosis methods. This paper describes the application of Hotelling $T^2$ index based Principal Component Analysis (PCA) method for fault detection and diagnosis in industrial processes. Multivariate statistical process control techniques are now widely used for performance monitoring and fault detection. Conventional methods such as PCA are suitable only for steady state processes. These conventional projection methods causes false alarms or missing data for the systems with transient values of processes. These issues significantly compromise the reliability of the monitoring systems. In this paper, a reliable method is used to overcome false alarms occur due to varying process conditions and missing data problems in transient states. This monitoring method is implemented and validated experimentally along with matlab. Experimental results proved the credibility of this fault detection method for both the steady state and transient operations.

• Elastomers and Composites
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• v.55 no.2
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• pp.81-87
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• 2020

Service life prediction and evaluation of rubber components is the foundational technology necessary for securing the safety and reliability of the product and to ensure an optimum design. Even though the domestic industry has recognized the importance thereof, technology for a systematic design and analysis of the same has not yet been established. In order to develop this technology, identifying the fatigue damage parameters that affect service life is imperative. Most anti-vibration rubber components had been damaged by repeated load and aging. Hence, the evaluation of the fatigue characteristics is indispensable. Therefore, in this paper, we propose a method that can predict the service life of rubber components relatively accurately in a short period of time. This method works even in the initial designing stage. We followed the service life prediction procedure of the proposed rubber components. The weak part of the rubber and the maximum strain were analyzed using finite element analysis of the rubber bushing for the tracked vehicles. In order to predict the service life of the rubber components that were in storage for a certain period of time, the fatigue test was performed on the three-dimensional dumbbell specimen, based on the results obtained by the rubber material acceleration test. The service life formula of the rubber bushing for tracked vehicles was derived using both finite element analysis and the fatigue test. The service life of the rubber bushing for tracked vehicles was estimated to be about 1.7 million cycles at room temperature (initial stage) and about 400,000 cycles when kept in storage for 3 years. Through this paper, the service life for various rubber parts is expected be predicted and evaluated. This will contribute to improving the durability and reliability of rubber components.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.38 no.3
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• pp.197-209
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• 2020

Signboards are installed in different types and sizes depending on the shop characteristics. However, the local government is having difficulty managing signboards with frequent opening and closing of stores and insufficient management personnel. In this study, a methodology was proposed to standardize and efficiently manage signboard information. To this end, the signboard display method of the enforcement ordinance related to outdoor advertising was analyzed to define the attribute elements of standard signboard data. In addition, physical information of signboards was obtained through signboard recognition technology, which is a prior study, and attribute elements of signboard standard data were defined through information that can be read with the naked eye, building integration information of the Ministry of the Interior and Safety, and street name address. In order to standardize the signboard information by spatial characteristics, data product specifications and metadata were defined according to the national spatial information standard. Lastly, standard data for signboards were produced in XML (Extensible Markup Language) format for compatibility, and XSD (XML Schema Definition) was defined for XML integrity so that data validity could be verified. Through this, a standard data model for the informatization of signboards was designed.

• Journal of the Korean Society of Food Culture
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• v.28 no.6
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• pp.594-602
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• 2013

This study investigated consumer perception and purchase behavior regarding Han-gwa (traditional Korean confection) in housewives residing in the Seoul and Gyeonggi area. This study was conducted by self-administered questionnaires. Out of 839 questionnaires, 713 questionnaires (85.0%) were used for statistical analyses including frequency analysis, the Chisquare, and one-way ANOVA. Based on the data collected, independence variables were divided less than 40 years (<40), 40s, 50 years or higher (50) by age. The major findings were as follows; Firstly, 72.1% of the total respondents had the experience of purchasing Han-gwa. Gangjeong was the most popular item among purchased. As the purpose of purchasing, holiday gift and snack was on the highest rank. Hypermarkets / discount stores (48.9%) was the most common place for the place of purchase. Secondly, there was a significant difference in the perception of Han-gwa by age; respondents aged 50 years or older showed more positive perception in Han-gwa in 3 factors among total of 11 factors. Thirdly, for the popularization of Han-gwa, 'too sweet taste (44.2%)' and 'small portion size (22.9%)' were pointed to be improved by respondents. Results of this study indicate that 1) Yu-gwa and Yak-gwa require new product development based on age segmentation, and health and food safety are important variables considered when housewives purchase Han-gwa.

• Preventive Nutrition and Food Science
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• v.10 no.2
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• pp.122-129
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• 2005

Chlorine dioxide $(ClO_2)$ treatment was evaluated for microbial growth inhibition and its effects on the quality of vacuum-packaged chicken breasts. Chicken breast samples were treated with 3, 50, and 100 ppm of $ClO_2$ solution, respectively. After $ClO_2$ treatment, chicken breast samples were individually vacuum-packaged and stored at $4^{\circ}C$, a typical storage temperature for meat and meat product, for 7 days. The vacuum-packaged chicken breasts treated with $ClO_2$ had significantly lower total bacteria, yeast and mold, total coliform, and Salmonella spp. were significantly reduced by $ClO_2$ treatment. $D_{10}-values$ of total bacteria count, yeast and mold, total coliform, and Salmonella spp. in vacuum-packaged chicken breasts was 93, 83, 85, and 50 ppm, respectively. The pH of vacuum-packaged chicken breasts decreased with increasing $ClO_2$ concentration. Thiobarbituric acid reacted substance (TBARS) values of vacuum-packaged chicken breasts increased during storage, regardless of $ClO_2$ concentration. $ClO_2$ treatment caused negligible changes in Hunter L, a, and b values in the vacuum-packaged chicken breasts. Sensory evaluation of the vacuum-packaged chicken breasts showed that there were no significant changes among the samples treated with various $ClO_2$ concentration. These results indicate that $ClO_2$ treatment could be useful in improving the microbial safety and quality of meat products.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.6
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• pp.1282-1291
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• 2009

A combined prescription of GGB and CHS (G&C prescription group) was used to investigate its effects on immune related factors and histological changes in atopic dermatitis(AD) induced mice. Significant decrease of atopic dermatitis clinical index in G&C prescription group. In DLN, G&C prescription group significantly modulated the immune cells. G&C prescription group also showed significant effect on the immune cells of the dorsal skin as well as DLN. The group indicated significant decrease of the biosynthesis of IL-4, IL-5, IL-13, GM-CSF, cytokines in serum. On the other hand, the biosynthesis of TNF-$\alpha$ was decreased. G&C prescription group significantly decreased the immunoglobulin IgE levels in serum. The results suggest that G&C prescription significantly improves atopic dermatitis through regulation of immune cells and cytokines. Comparative studies with Protopic ointment also showed that G&C prescription showed significant effect in AD patients, and active application of the prescription in clinicals is anticipated. However, the reason for the results that oppose to those of previous studies should be investigated. Also, therapeutic effects of both internal and external applications should be studied individually as well as for any synergistic effects. Safety, toxicity, as well as stability studies should follow to develop G&C prescription into long-term external clinical product.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.1
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• pp.179-182
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• 2005

Recently gene fabrication foodstuffs, remained chemicals and heavy metal on the agricultural product gets prominent, consciousness of consumers is getting higher regarding safety and quality problems of consumer products. A measurement should be done immediately because the research concerned about this has not been made compared to the foreign countries such as Europe, United States, Japan and so on has quickly accepted production record system. In this paper, we designed all the procedures among the production, postharvest, packing, storing should be done without any kinds of harm that could be happened from the farm to the dinner tables of each family as possible as we can. And also we defined the data system in accordance with the domestic agricultural system and realized the production trace system on the base of Good Agriculture Practices(GAPs) in order to let the consumers confirm the procedures themselves.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2006.05a
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• pp.931-934
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• 2006

Recently, as the problems related to agricultural product's safety occur continuously, the system with traceability that can quickly trace back the agricultural products with problems occurred and enable the analysis of causes and prohibition of distribution is required. Therefore, the recording of distribution data is important for this system and for this purpose, the RFID technology that can perceive tags from remote place through radio frequency can be effectively used. But, since the RFID is a technology that is being watched recently, the system that processes RFID tags and distribution data is trifling. Hereby, this thesis designed and implemented the RFID processing system that enables the career trace by analyzing and managing the data on recorded RFID tags and career data based on the standard of traceability.