• Journal of the Korean Society for Nondestructive Testing
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• v.21 no.3
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• pp.299-306
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• 2001

In this paper, artificial and real defects(delamination and debond) in composite structures were detected by using ESPI system. Three types of specimens, that is, composite laminates, honeycomb structures, and adhesive joints, were used to study the applicability of ESPI to composite structures. To detect defects in specimens, we selected thermal loading method that can easily induce the surface deformation of specimen. Experimental results show that defects in composite structures could be easily detected by ESPI. Moreover, it shows that ESPI could be usefully applied to the detection of defects in various composite structures.

• The Journal of the Acoustical Society of Korea
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• v.20 no.5
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• pp.54-60
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• 2001

This paper investigates the equivalent circuit analysis method for the multi-functional device in mobile telephones, which works both as a buzzer and a vibrator in a single unit form. With a representative multi-functional device, we construct the corresponding equivalent circuits for the buzzer mode and the vibrator mode of the device, respectively, and analyze the performance of each of the modes. For proper construction of the circuit, we analyze the structure and operation mechanism of the device, and develop a computer simulation tool to simulate the behavior of the device. Validity of the analysis method is verified through comparison of the analysis results with experimental measurement results, which shows good agreement between the two sets of data.

• Journal of Navigation and Port Research
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• v.31 no.5 s.121
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• pp.385-393
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• 2007

This study aims to verify the structural relationship among service orientation, employees' satisfaction and business performance primarily on the International Freight Forwarders. For carrying out the study, literature survey relating to service orientation, satisfaction and performance along with empirical analysis was carried out. Results of analyses were found to be as follows: first, International Freight Forwarder's service orientation has had influence on employees' satisfaction second, employees' satisfaction in the freight forwarding companies has had influence on financial performance.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.30 no.5
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• pp.48-55
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• 2002

An Internet-based software called the Repair Advisory Service (RAS) was developed to assist aircraft composite repair. The RAS takes advantage of the web user interface and provides estimation of the failure loads of repaired composite laminates and Structural Repair Manual (SRM) with search capability. In this paper, a failure model of lap repair is discussed as an example of the modules in the RAS. The model takes into account anisotropy of each ply in the laminate and in the repair ply, and non-elastic behavior of the interlayer between the laminate and the repair patch. Failure loads calculated by the model were compared with test data, and a good agreement was found between the results of the model and the test.

• Journal of Digital Convergence
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• v.13 no.10
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• pp.549-559
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• 2015

This study aimed to find the problems of evidence-based complementary and alternative medicine and seek the future development direction by evaluating the quality of oriental medicine related systematic review(SR) studies using AMSTAR tool. The 26 SR studies related to oriental medicine were searched from the database of DBPIA, OASIS, and KISS, and they were evaluated on the basis of AMSTAR. The average of AMSTAR for the quality assessment of SR studies was 6.0 point, and the 26 studies included 2 high quality studies (7.7 %), 21 normal quality studies (80.8 %), and 3 low quality studies (11.5 %). The quality of studies was not correlated with the publication years. The quality of oriental medicine related SR studies need to be improved steadily. Furthermore, continued efforts to promote the evidence-based practice in the field of Oriental Medicine will help to establish foundation for the convergence approach in the healthcare sector.

• Journal of the korean academy of Pediatric Dentistry
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• v.46 no.3
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• pp.310-317
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• 2019

The purpose of this retrospective study was to evaluate the survival rate of composite resin restorations in permanent first molars in pediatric patients focusing on the influence of risk factors related to patients and teeth. 172 patients (6 - 12 years old) who had their permanent first molars restored with composite resin from July 2010 to July 2012 were investigated. From the dental records, the influence of the risk factors on the survival of restorations was assessed. Location of teeth, classification of cavities, patients' age and caries risk were included as risk factors in this study. The caries risks of patients were evaluated by the value of the decayed-missing-filled teeth index with the records of patients taken at 5 years old. Among 354 restorations, 272 restorations retained and 82 restorations were replaced. The overall cumulative survival rate at 5 years was 73.9%. The main reason for replacement of restorations was secondary caries (81.7%). Patients with older age group and with lower caries risk group showed higher survival rate of restorations. No statistically significant influence was detected between the survival rates and the possible risk factors : location of teeth, patients' age and caries risk. The survival rate of restorations was significantly affected by the classification of the cavities (p = 0.002).

• Journal of the Korean Applied Science and Technology
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• v.38 no.2
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• pp.368-377
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• 2021

The present study aimed to evaluate the effects of radiation mutant Perilla frutescens var. crispa and Atractylodes macrocephala Koidzumi complex extract(Perilla frutescens var. crispa complex extract) on the mediators related to degenerative arthritis in a monosodium iodoacetate-induced rat model of degenerative arthritis. Perilla frutescens var. crispa complex extract was administered orally at doses of 25, 50 or 100 mg/kg/day for 2 weeks before direct injection of monosodium iodoacetate (3 mg/50 µl of 0.9% saline) into the intra-articular space of the rats' right knees. The rats subsequently received the same doses of oral Perilla frutescens var. crispa complex extract for another 4 weeks. It was evaluated that the treatment effects based on serum bio-markers, and morphological and histopathological analysis of the knee joints. Compared with those in negative control rats, the Perilla frutescens var. crispa complex extract treatments significantly reduced the serum levels of inflammation, bone metabolism markers (i.e., TNF-α, MMP-3, COX-2, PGE₂, COMP, and Aggrecan). Otherwise, it was significantly increased the production of CTX-2 in cartilage absorption mediators. In addition, the Perilla frutescens var. crispa complex extract treatments effectively preserved the knee cartilage and synovial membrane. As a result, it indicates that the Perilla frutescens var. crispa complex extract improved degenerative arthritis symptoms. Thus, the Perilla frutescens var. crispa complex can be used in food material for the management of degenerative arthritis.

• Korean Journal of Poultry Science
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• v.29 no.1
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• pp.19-23
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• 2002

This studs was conducted to investigate the effects of dietary carbohydrase (multi-enzyme: $\alpha$-galactosidase and mannanase) on egg quality and nutrient digestibility in laying hens. One hundred forty four, 47-wk-old, ISA Brown commercial layers were used in a 28-d feeding trial after a 7-d adjustment period. Dietary treatments were 1) CON(basal diet), 2) ME 0.1 (basal diet +0.1% multi -enzyme), 3) ME 0.2 (basal diet + 0.2% multi-enzyme). Fer overall Period, hen-day egg Production, egg weight, egg shell breaking strength and egg shell thickness were not influenced by the multi-enzyme. As the adding levels of multi-enzyme increased in the diet, egg Yolk color and egg Yolk index tended to increase with significant differences. Digestibility of DM was not affected by multi-enzyme. However, digestibility of N increased significantly as the concentration of multi-enzyme in the diet was increased. In conclusion, supplemental carbohydrase in laying hen diets nay have some roles in improving the egg Yolk color and N digestibility.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.30 no.6_1
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• pp.549-557
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• 2012

Spatial phenomena such as environment pollution, disease and the risk of spreading information need a rapid initial response to perceive spread event. Moving data perceive spread event through real-time processing and analysis. To process and analysis the event, spatial-temporal complex event processing is used. Previous spatialtemporal complex event processing is possible basis spatial operator but insufficient apply to design spatialtemporal complex event processing to perceive spatial phenomena of high complexity. This study proposed hierarchical spatio-temporal CEP design which will efficiently manage the fast growing incoming sensor data. The implementation of the proposed design is evaluated with GPS location data of moving vehicles which are used as the incoming data stream for identifying spatial events. The spatial component of existing CEP software engine has been extended during the implementation phase to broaden the capabilities of processing spatio-temporal events.

• Korean Journal of Materials Research
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• v.9 no.3
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• pp.307-314
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• 1999

The effect of manufacturing variables, such as reactant powder$(TiB_2, B_4C)$, sintering temperature, and sintering time has been investigated on the microstructure and the mechanical properties of in-situ processed Ti/TiB composites. The mechanical properties were evaluated by measuring the compressive yield strength. The compressive yield strength of the in-situ processed composites was higher than that of the Ti-6AI-4V. The compressive yield strength of the composite made with TiE, reactant powder was higher than that of $B_4C$, mixed at the same volume fraction of reinforcement. It is because bonding nature between the matrix and the $TiB_2$, reactant powder was more strong than that of the other materials. It was proven by the examining the crack propagation path.