• Proceedings of the KSME Conference
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• 2001.06a
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• pp.459-464
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• 2001

For major nuclear power plant components periodic inspections and integrity assessments are needed for the safety. But many flaws are undetectable due to sampling inspection. Probabilistic integrity assessment is applied to take into consideration of uncertainty and variance of input parameters arise due to material properties, applied load and undetectable flaws. This paper describes a Probabilistic Fracture Mechanics(PFM) analysis based on Monte Carlo(MC) algorithms. Taking important parameters as probabilistic variables such as fracture toughness, crack growth rate and flaw shape, failure probability of major nuclear power plant components is archived as a results of MC simulation. For the verification of these analysis, a comparison study of the PFM analysis using other commercial code, mathematical method is carried out and a good agreement was observed between those results.

• Journal of Korean Society for Quality Management
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• v.17 no.1
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• pp.1-10
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• 1989

In general, the characteristics of components which consist of multi-component system can not be the same. This paper proposes a maintenance model of multi-component system considering the characteristics of each component. In this paper, multi-component system is divided into three components-critical unit, major unit and minor unit, respectively. This paper determines the optimal replacement time of the system which minimizes total maintenance cost, optimal replacement period of major unit and initial stock quantity of minor unit within this optimal replacement time. Numerical examples are shown when the failure times of each unit have gamma distribution.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2003.05a
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• pp.415-423
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• 2003

Korea Electric Power Research Institute(KEPRI) had worked a comprehensive Plant Lifetime Management (PLiM) project for a CANDU plant in corporation with Korea Hydro and Nuclear Power(KHNP). The project had been performed to understand the aging status of major components screened from the plant and to address provisions for the continued operation over its design life. A feasibility of the continued operation was reviewed in the aspects of technology, economics, and regulatory environments. This paper introduces general approach of aging assessment, screening of critical components and an experience of aging assessment for an example of fuel channel that is the most critical component in CANDU plant.

• Korean Journal of Food Science and Technology
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• v.28 no.3
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• pp.433-439
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• 1996

Major components affecting nonenzymatic browning in stored ginger paste were investigated using five synthetic model solutions.　The model systems were stored at $40^{\circ}C$ for 30 days and analyzed for browning, in addition the contents of sugars, organic acids, ascorbic acids, amino acids and gingerols were determined. Among the chemical components, fructose, asparagine and ascorbic acid were the main contributors to the browning development of ginger paste, while gingerol compounds were browning inhibitors.

• Korean Journal of Remote Sensing
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• v.4 no.1
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• pp.49-60
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• 1988

Principal Component Analysis (PCA) was applied for regional geological mapping to a multivariate data set of the Landsat TM data in the heavily vegetated and topographically rugged Chungju area. The multivariate data set selection was made by statistical analysis based on the magnitude of regression of squares in multiple regression, and it includes R1/2/R3/4, R2/3, R5/7/R4/3, R1/2, R3/4. R4/3. AND R4/5. As a result of application of PCA, some of later principal components (in this study PC 3 and PC 5) are geologically more significant than earlier major components, PC 1 and PC 2 herein. The earlier two major components which comprise 96% of the total information of the data set, mainly represent reflectance of vegetation and topographic effects, while though the rest represent 3% of the total information which statistically indicates the information unstable, geological significance of PC3 and PC5 in the study implies that application of the technique in more favorable areas should lead to much better results.

• Journal of Veterinary Clinics
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• v.21 no.3
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• pp.264-269
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• 2004

A retrospective analysis was performed with 270 cases of canine urolithiasis examined at Laboratory of Clinical Pathology, College of Veterinary Medicine, Seoul Nat'l University in the period between January 2001 and December 2003. The Shih-Tzu (64 cases), Yorkshire terrier (60 cases), miniature schnauzer (41 cases) and maltese terrier (36 cases) had higher incidences than other breeds. Canine urolithiasis occurred from 4 months to 15 years of age, but the most prevalent age was 3 years. Mean age was $5.68\pm3.14$ years. The major mineral component. of calculi was struvite (54.1%) and calcium oxalate (30.4%). There was no sex prevalences: male 131 cases, female 132 cases. The most prevalent anatomic locations of calculi were urinary bladder (53 of 131 cases), urethra (24 of 131 cases) and bladder/urethra (45 of 131 cases) in males and urinary bladder (103 of 132 Cases) in females. The major mineral component of calculi in urinary bladder was struvite (102 of 160 cases), and that in urethra (13 of 25 cases) and multiple locations (29 of 62 cases) was calcium oxalate: The major components of calculi were not always consistent with the components which could be expected from urine pH and crystals. So it is suggested that the components of the calculi must be analyzed after surgical removal to prevent the recurrence when the calculi could not be dissolved by diets or urine pH modifiers.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.181-185
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• 2008

Recently, the Virtual Reality(VR) became one of the most powerful tools in making media files. In the field of engineering, while it is increasing to use 3D CAD model in the process of design to manufacturing, the VR is not popular in comparison with media business. XVL(eXtensible Virtual Reality Markup Language) is one of XML(eXtensible Markup Language) which is a standard web media language. XVL provides the connection between 3D CAD data and virtual reality, and it can be easily published through internet for the engineering purpose. In this study, a web based VR model for major components in a nuclear power plant has been developed by using XVL and corresponding 3D CAD data. The proposed model is expected to be used in the engineering field to cooperate among experts, and also, it will provide more plausible explanation to ordinary people.

• The Journal of Information Systems
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• v.30 no.3
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• pp.177-199
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• 2021

Purpose This study explores the development direction of the artificial intelligence curriculum as a universal education that enhances the ability of college students to flexibly use artificial intelligence these days, where artificial intelligence education is spreading, and the educational components based on this are subdivided according to the characteristics of each major. Design/methodology/approach In order to develop the educational purpose of the subject and the detailed educational curriculum suitable for the subject of education, we first analyzed domestic and foreign prior research related to artificial intelligence liberal arts education. As the main components derived by experts, the basic concept of artificial intelligence converges to literacy to read and write for everyday problem solving, as well as problem-solving ability to manipulate real data and software. Findings The results showed that In the artificial intelligence literacy module, trends and prospects of artificial intelligence and necessary competencies were checked, and cases applied to major fields were examined. In the AI utilization and application part, basic data analysis items and content composition were composed through creative thinking, logical thinking, and intelligence. In order to design the curriculum, a software development language suitable for each major area was first selected, and AI education content areas, elements, and packages were defined and designed for each major area to meet the objectives of the subject.

• Korean Journal of Medicinal Crop Science
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• v.23 no.5
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• pp.395-399
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• 2015

Background : This study examined the effect of harvesting time on the growth, yield characteristics, and major beneficial components in Salvia miltiorrhiza. Methods and Results : Although plant height, stem diameter and branch length were not affected by harvesting time, the number of stems was highest when harvested in mid October. There were no differences in root length and thickness, however, the rhizome was thicker when it was harvested at the end of October or early November than when it was harvested in early and mid October. The dried root weight also showed a similar pattern. However, there was a statistically significant increase to 408 kg (16%) in the rhizome weight when in late October and a rise to 455 kg (29%) when harvested in early November. Harvest time had little effect on the content of the major component of S. miltiorrhiza. For example, salvianolic acid content rose from 9.42 to 9.64% with later harvest times, and tanshinone ${\prod}A$ content was tended to be slightly more increased in mid October which S. miltiorrhiza has 0.22% tanshinon ${\prod}A$ than in early October. Conclusions : According to these results, the optimum harvest time for S. miltiorrhiza is early November when plant or major component yields are hightest. There were no significant harvest time effects on the major beneficial components.

• International Journal of Oral Biology
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• v.32 no.2
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• pp.75-78
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• 2007

The periodontal diseases and dental caries are major infectious diseases in oral cavity. Many of the preventive and therapeutic dental products contain the antimicrobial and anti-inflammatory components. But some of these antimicrobial have weak points such as coloration, burning sensation and insolubility in water. We have screened the therapeutic herbal extracts of the Plant Extract Bank for the antimicrobial activity on the major dental pathogens by growth inhibition assay. For the Porphyromonas gingivalis, 8 herbal extracts had an antimicrobial activity, 11 herbal extracts for the Prevotella intermedia, 43 herbal extracts for the Haemophilus actinomycetemcomitans and 61 herbal extracts for the Streptococcus mutans. Among these extracts, 6 herbal extracts had an antimicrobial activity for more than 3 species of dental pathogens. These extracts are Araliae Cordatae Radix, Crassirhizomae Rhizoma, Mori Radicis Cortex, Psoraleae Semen, Pini Ramulus and Sieges- beckiae Herba. All of effective extracts were CA group, ethanol extracts. Among these 6 herbal extracts, only Crassirhizomae is known to have a antibacterial effects. Therefore these herbal extracts have a possibility to be a candidate for a major antibacterial components in dental products.