• Korean Journal of Veterinary Service
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• v.29 no.1
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• pp.1-8
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• 2006

Porcine circovirus (PCV) is a small, nonenveloped virus that contains a single-stranded circular DNA genome of about 1.76 kb and belongs to the family circoviridae. The PCV-2 has been incriminated as the cause of post-weaning multisystemic wasting syndrome (PMWS) , an emerging disease in pigs. In the present study, a PCR assay was applied to detect PCV-2 in tissue samples. The presence of PCV-2 antigen in the porcine tissues was confirmed by indirect immunofluorescence (IIF) with PCV-2 specific monoclonal antibodies. And then DNA extracted from PCV-2 positive tissues was used as a template. One oligonucleotide primer suitable for PCR was selected from a published PCV-2 sequence (Genbank). Amplified PCR product was detected the same fragment lengths of 416 bp as a control. Based on these results, it was suggested that the PCR is a simple and sensitive method for support diagnostic purposes.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.1440-1445
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• 2008

There are 21 abondoned coal mines drained out mine water in gyeong sang do. We monitored the water quality of 31 mine drainage from 1995. The most of mine drainage was neutral as the average pH was 6.22 and Fe, Mn, Al concentration was below 10mg/L. The result showed the tendency of decreasing of flow and metal concentration. The highest Mn concentration was detected in bonghwa area and the hightest Fe concentration was detected in munkyung area. It means that the water quality is closly related to geological features.

• Korean Journal of Computational Design and Engineering
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• v.9 no.1
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• pp.51-61
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• 2004

Mechanical parts are often grouped into part families based on the similarity of their shapes, to support efficient manufacturing process planning and design modification. The 2-part sequence papers present similarity assessment techniques to support part family classification for machined parts. These exploit the multiple feature decompositions obtained by the feature recognition method using convex decomposition. Convex decomposition provides a hierarchical volumetric representation of a part, organized in an outside-in hierarchy. It provides local accessibility directions, which supports abstract and qualitative similarity assessment. It is converted to a Form Feature Decomposition (FFD), which represents a part using form features intrinsic to the shape of the part. This supports abstract and qualitative similarity assessment using positive feature volumes.. FFD is converted to Negative Feature Decomposition (NFD), which represents a part as a base component and negative machining features. This supports a detailed, quantitative similarity assessment technique that measures the similarity between machined parts and associated machining processes implied by two parts' NFDs. Features of the NFD are organized into branch groups to capture the NFD hierarchy and feature interrelations. Branch groups of two parts' NFDs are matched to obtain pairs, and then features within each pair of branch groups are compared, exploiting feature type, size, machining direction, and other information relevant to machining processes. This paper, the second one of the two companion papers, describes the similarity assessment method using NFD.

• Korean Journal of Computational Design and Engineering
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• v.9 no.1
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• pp.44-50
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• 2004

Mechanical parts are often grouped into part families based on the similarity of their shapes, to support efficient manufacturing process planning and design modification. The 2-part sequence papers present similarity assessment techniques to support part family classification for machined parts. These exploit the multiple feature decompositions obtained by the feature recognition method using convex decomposition. Convex decomposition provides a hierarchical volumetric representation of a part, organized in an outside-in hierarchy. It provides local accessibility directions, which supports abstract and qualitative similarity assessment. It is converted to a Form Feature Decomposition (FFD), which represents a part using form features intrinsic to the shape of the part. This supports abstract and qualitative similarity assessment using positive feature volumes. FFD is converted to Negative Feature Decomposition (NFD), which represents a part as a base component and negative machining features. This supports a detailed, quantitative similarity assessment technique that measures the similarity between machined parts and associated machining processes implied by two parts' NFDs. Features of the NFD are organized into branch groups to capture the NFD hierarchy and feature interrelations. Branch groups of two parts' NFDs are matched to obtain pairs, and then features within each pair of branch groups are compared, exploiting feature type, size, machining direction, and other information relevant to machining processes. This paper, the first one of the two companion papers, describes the similarity assessment methods using convex decomposition and FFD.

• Steel and Composite Structures
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• v.35 no.2
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• pp.215-235
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• 2020

Cracks and defects may occur anywhere in a plate under tension. Cracks can affect the buckling stability performance and even the failure mode of the plate. A search of the literature reveals that the reported research has mostly focused on the study of plates with central and small cracks. Considering the effectiveness of cracks on the buckling behavior of plates, this study intends to investigate the effects of some key parameters, i.e., crack size and location as well as the plate aspect ratio and support conditions, on the buckling behavior, stress intensity factor (SIF), and the failure mode (buckling or fracture) in cracked plates under tension. To this end, a sophisticated mathematical code was developed using MATLAB in the frame-work of extended finite element method (XFEM) in order to analyze the buckling stability and collapse of numerous plate models. The results and findings of this research endeavor show that, in addition to the plate aspect ratio and support conditions, careful consideration of the crack location and size can be quite effective in buckling behavior assessment and failure mode prediction as well as SIF evaluation of the cracked plates subjected to tensile loading.

• Bulletin of the Korean Chemical Society
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• v.33 no.8
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• pp.2724-2730
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• 2012

A new heterogeneous acidic catalyst was successfully prepared by impregnation of silica (Aerosil 300) by an acidic ionic liquid, named 1-(4-sulfonic acid)butylpyridinium hydrogen sulfate [$PYC_4SO_3H$][$HSO_4$], and characterized using FT-IR spectroscopy, the $N_2$ adsorption/desorption analysis (BET), thermal analysis (TG/DTG), and X-ray diffraction (XRD) techniques. The amount of loaded acidic ionic liquid on Aerosil 300 support was determined by acid-base titration. This new solid acidic supported heterogeneous catalyst exhibits excellent activity in the synthesis of 2-aryl-2,3-dihydroquinazolin-4(1H)-ones by cyclocondensation reaction of 2-aminobenzamide with aromatic aldehydes under solvent-free conditions and the desired products were obtained in very short reaction times with high yields. This catalyst has the advantages of an easy catalyst separation from the reaction medium and lower problems of corrosion. Recycling of the catalyst and avoidance of using harmful organic solvent are other advantages of this simple procedure.

• Journal of the korean society of oceanography
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• v.32 no.1
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• pp.1-7
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• 1997

Surface current fields in the eastern East China Sea (ECS) were constructed by analyzing trajectories of 58 satellite-tracked surface drifters released during 1991-1996. Composite trajectories and 20-minute-by-20-minute box-averaged current vectors show that the basic current pattern composes of: the Kuroshio main stream, which turns eastward toward the Tokara Strait; a northward branch current of the Kuroshio on the ECS outer shelf deeper than 100 m; and an anticyclonic circulation in the northern Okinawa Trough west of Kyushu. The northward branch current sharply changes its direction to the northeast when it crosses a line connecting Cheju Island, Korea and Goto Islands, Japan. The basic pattern of current field changes slightly from winter to summer, and the main axis of the Tsushima Current in the Korea Strait is found to shift seasonally. The drifter experiment does not support the claim that the Yellow Sea Warm Current is separated from the northward branch current on the outer shelf southeast of Cheju Island. We suggest that the use of the term 'Tsushima Current' be limited to the northeast channel flow in the Korea Strait. The new term 'Kuroshio Branch Current' is suggested for the northward branch current on the outer shelf south of Cheju-do, which is separated from the Kuroshio.

• Journal of the Korean Society of School Health
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• v.28 no.2
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• pp.120-126
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• 2015

Purpose: The purpose of this study was to understand interpersonal dispositions and social support among high school students and identify factors associated with depression. Methods: A total of 604 students (320 males and 284 females) from four high schools conveniently sampled from high schools in the Incheon area participated in a self-administered survey. Results: According to hierarchical multiple regression analysis, the following factors significantly affected the participants' depression levels with the explanatory power of 30.6%: grade, perceived health status, sympathetic-acceptable personality, sociable-friendly personality, rebellious-distrustful personality, parent support, peer support, and the support from community. Conclusion: In this study, interpersonal dispositions and social support were positively associated with depression. These results suggest that strengthening personal relations and social support can help high school students in terms of mental health and suicide prevention.

• Smart Structures and Systems
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• v.22 no.4
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• pp.413-424
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• 2018

The factors affecting the shear strength of the angle shear connectors in the steel-concrete composite beams can play an important role to estimate the efficacy of a composite beam. Therefore, the current study has aimed to verify the output of shear capacity of angle shear connector according to the input provided by Support Vector Machine (SVM) coupled with Firefly Algorithm (FFA). SVM parameters have been optimized through the use of FFA, while genetic programming (GP) and artificial neural networks (ANN) have been applied to estimate and predict the SVM-FFA models' results. Following these results, GP and ANN have been applied to develop the prediction accuracy and generalization capability of SVM-FFA. Therefore, SVM-FFA could be performed as a novel model with predictive strategy in the shear capacity estimation of angle shear connectors. According to the results, the Firefly algorithm has produced a generalized performance and be learnt faster than the conventional learning algorithms.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.1
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• pp.49-56
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• 2012

Objective: This study was an attempt to identify associations between health behavior, such as smoking, alcohol consumption, healthy diet, and physical activity, and psychosocial factors. Methods: This crosssectional study was conducted among 1,500 participants aged between 30 and 69 years, selected from a population-based database in October 2009 through multiple-stratified random sampling. Information was collected about the participants' smoking and drinking habits, dietary behavior, level of physical activity, stress, coping strategies, impulsiveness, personality, social support, sense of coherence, self-efficacy, health communication, and sociodemographics. Results: Agreeableness, as a personality trait, was negatively associated with smoking and a healthy diet, while extraversion was positively associated with drinking. The tendency to consume a healthy diet decreased in individuals with perceived higher stress, whereas it increased in individuals who had access to greater social support. Self-efficacy was found to be a strong predictor of all health behaviors. Provider-patient communication and physical environment were important factors in promoting positive healthy behavior, such as consumption of a healthy diet and taking regular exercise. Conclusions: Psychosocial factors influence individuals' smoking and drinking habits, dietary intake, and exercise patterns.