• The Journal of Advanced Prosthodontics
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• v.6 no.3
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• pp.224-232
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• 2014

PURPOSE. The purpose of the present study was to evaluate the effect of thermocycling and mechanical loading on the biaxial flexural strength and the phase transformation of one Ce-TZP/$Al_2O_3$ and two Y-TZP core materials. MATERIALS AND METHODS. Thirty disc-shaped specimens were obtained from each material. The specimens were randomly divided into three groups (control, thermocycled, and mechanically loaded). Thermocycling was subjected in distilled water for 10000 cycles. Mechanical loading was subjected with 200 N loads at a frequency of 2 Hz for 100000 times. The mean biaxial flexural strength and phase transformation of the specimens were tested. The Weibull modulus, characteristic strength, 10%, 5% and 1% probabilities of failure were calculated using the biaxial flexural strength data. RESULTS. The characteristic strengths of Ce-TZP/$Al_2O_3$ specimens were significantly higher in all groups compared with the other tested materials (P<.001). Statistical results of X-ray diffraction showed that thermocycling and mechanical loading did not affect the monoclinic phase content of the materials. According to Raman spectroscopy results, at the same point and the same material, mechanical loading significantly affected the phase fraction of all materials (P<.05). CONCLUSION. It was concluded that thermocycling and mechanical loading did not show negative effect on the mean biaxial strength of the tested materials.

• Restorative Dentistry and Endodontics
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• v.41 no.4
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• pp.271-277
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• 2016

Objectives: In this study, we evaluated the influence of different radiant exposures provided by single-peak and polywave light-curing units (LCUs) on the degree of conversion (DC) and the mechanical properties of resin cements. Materials and Methods: Six experimental groups were established for each cement (RelyX ARC, 3M ESPE; LuxaCore Dual, Ivoclar Vivadent; Variolink, DMG), according to the different radiant exposures (5, 10, and $20J/cm^2$) and two LCUs (single-peak and polywave). The specimens were made (7 mm in length ${\times}$ 2 mm in width ${\times}$ 1 mm in height) using silicone molds. After 24 hours of preparation, DC measurement was performed using Fourier transform infrared spectrometry. The same specimens were used for the evaluation of mechanical properties (flexural strength, FS; elastic modulus, E) by a three-point bending test. Data were assessed for normality, after which two-way analysis of variance (ANOVA) and post hoc Tukey's test were performed. Results: No properties of the Variolink cement were influenced by any of the considered experimental conditions. In the case of the RelyX ARC cement, DC was higher when polywave LCU was used; FS and E were not influenced by the conditions evaluated. The LuxaCore cement showed greater sensitivity to the different protocols. Conclusions: On the basis of these results, both the spectrum of light emitted and the radiant exposure used could affect the properties of resin cements. However, the influence was material-dependent.

• Korean Journal of Social Welfare
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• v.65 no.1
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• pp.5-31
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• 2013

The principle objective of this study is to determine factors affecting social participation for physically disabled people with musculoskeletal conditions (spinal cord injury, muscular dystrophy, osteogenesis imperfecta, rheumatoid arthritis) in South Korea using ICF relevant categories of the international classification index by WHO. The subjects of this study 352 people with physical disabilities, the data were collected using ICF component(body functions, body structures, activities and participation and environmental factors) and the relevant categories deprived from ICF core sets. The collected data were evaluated with descriptive analysis, ANOVA, correlation analysis, and multiple regression analysis. The results of this study can be summarized as follow. The mental function, Neuromusculoskeletal and movement-related functions, Genitourinary and reproductive functions, Skin and related structures, Learning and applying knowledge, General tasks and demands, and Mobility positively influenced social participation in people with musculoskeletal conditions. However individual factors and environmental factors didn't statistically significant affect on social participation. The implications of the study is to examine by ICF components of universal approach on disability study and utilized the relevant ICF categories as measurement tools.

• International Commerce and Information Review
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• v.15 no.1
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• pp.135-159
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• 2013

The globalization of business is making it more important than ever to understand how international human resource can be utilized more competitively. This study explores how the international human resource strategies between global integration and local responsiveness affects the company's competitive advantage. The findings for global integration strategy suggest that when a subsidiary is highly dependent on the parent company's resources and the findings for local responsiveness suggest that when a subsidiary is highly dependant on the host country's resources and institution. This study proposes competitive advantage by the global integration strategy and local responsiveness strategy. The effects of IHRM to create value for company's core competence was analyzed. Two IHRM strategic choices will affect the different competences such as integration and localization abilities. This paper also suggests the two kinds of core competences of IHRM strategies how impact on company's performance.

• Molecules and Cells
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• v.41 no.2
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• pp.140-149
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• 2018

The $TIS21^{/BTG2/PC3}$ gene belongs to the antiproliferative gene (APRO) family and exhibits tumor suppressive activity. However, here we report that TIS21 controls lipid metabolism, rather than cell proliferation, under fasting condition. Using microarray analysis, whole gene expression changes were investigated in liver of TIS21 knockout (TIS21-KO) mice after 20 h fasting and compared with wild type (WT). Peroxisome proliferator-activated receptor alpha ($PPAR{\alpha}$) target gene expression was almost absent in contrast to increased lipid synthesis in the TIS21-KO mice compared to WT mice. Immunohistochemistry with hematoxylin and eosin staining revealed that lipid deposition was focal in the TIS21-KO liver as opposed to the diffuse and homogeneous pattern in the WT liver after 24 h starvation. In addition, cathepsin E expression was over 10 times higher in the TIS21-KO liver than that in the WT, as opposed to the significant reduction of thioltransferase in both adult and fetal livers. At present, we cannot account for the role of cathepsin E. However, downregulation of glutaredoxin 2 thioltransferase expression might affect hypoxic damage in the TIS21-KO liver. We suggest that the $TIS21^{/BTG2}$ gene might be essential to maintain energy metabolism and reducing power in the liver under fasting condition.

• Journal of Industrial and Engineering Chemistry
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• v.68
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• pp.14-23
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• 2018

$TiO_2-coated$ cubic ${\alpha}-Fe_2O_3$ with mostly exposed (012) and (101) facets (${\alpha}-Fe_2O_3@TiO_2$) was fabricated using a hydrothermal route for the photo-Fenton degradation of tetracycline under visible light irradiation. $TiO_2$ coating could greatly affect the photocatalytic activity of ${\alpha}-Fe_2O_3@TiO_2$. Compared with cubic ${\alpha}-Fe_2O_3$ alone for photodegradation of tetracycline, ${\alpha}-Fe_2O_3@TiO_2$ with $TiO_2$ shell of around 15 nm exhibited higher removal efficiency of tetracycline in photo-Fenton system, and its durability was slightly affected after five cycle times under same conditions. It is ascribed to the well-matched interface between cubic ${\alpha}-Fe_2O_3$ core and $TiO_2$ shell, leading to the broadened light-absorption and the efficient separation of photo-generated electon-hole pairs. The $^{\bullet}OH$ radicals were main responsible for the advanced photocatalytic performance of ${\alpha}-Fe_2O_3@TiO_2$ in visible-light driven degradation of tetracycline.

• Journal of the Korean Magnetics Society
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• v.16 no.5
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• pp.249-254
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• 2006

CoFeNi alloys are some of the most studied soft magnetic materials because of their superial properties over FeNi alloys as write head core materials in HDD and MEMS. We studied the effect of magnetic property according to size and orientation of crystal for electroplated Co-Fe-Ni alleys. In case of heat treated ternary alloy, it affect the change of crystal size and structure. In this study, it intends to improve the magnetic properties of CoFeNi thin film by heat treatment. Minimized coercivity and increased magnetization are due to heat treatment from $300^{\circ}C\;to\;400^{\circ}C$. As a bcc phase formation, it grow to amount of magnetization.

• Steel and Composite Structures
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• v.48 no.3
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• pp.275-291
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• 2023

This paper has focused on presenting vibration analysis of trapezoidal sandwich plates with 3D-graphene foam reinforced polymer matrix composites (GrF-PMC) core and FG wavy CNT-reinforced face sheets. The porous graphene foam possessing 3D scaffold structures has been introduced into polymers for enhancing the overall stiffness of the composite structure. Also, 3D graphene foams can distribute uniformly or non-uniformly in the plate thickness direction. The effective Young's modulus, mass density and Poisson's ratio are predicted by the rule of mixture. In this study, the classical theory concerning the mechanical efficiency of a matrix embedding finite length fibers has been modified by introducing the tube-to-tube random contact, which explicitly accounts for the progressive reduction of the tubes' effective aspect ratio as the filler content increases. The First-order shear deformation theory of plate is utilized to establish governing partial differential equations and boundary conditions for trapezoidal plate. The governing equations together with related boundary conditions are discretized using a mapping-generalized differential quadrature (GDQ) method in spatial domain. Then natural frequencies of the trapezoidal sandwich plates are obtained using GDQ method. Validity of the current study is evaluated by comparing its numerical results with those available in the literature. It is explicated that 3D-GrF skeleton type and weight fraction, carbon nanotubes (CNTs) waviness and CNT aspect ratio can significantly affect the vibrational behavior of the sandwich structure. The plate's normalized natural frequency decreased and the straight carbon nanotube (w=0) reached the highest frequency by increasing the values of the waviness index (w).

• Biomedical Science Letters
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• v.29 no.1
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• pp.48-52
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• 2023

Formaldehyde use is associated with serious health risks, which can affect medical personnel and technicians. Therefore, we investigated the efficacy of an alternative fixative, with respect to two types of formalin fixatives, by hematoxylin and eosin (H&E) staining, periodic acid Schiff (PAS) staining, immunohistochemical (IHC) staining, and RNA extraction. For H&E staining, the circular nucleus was stained dark blue by the basic dye hematoxylin and the cytoplasm was stained red by the acid dye eosin in all three fixative samples. No difference was found in the Duksan General Science (DGS), Sigma-Aldrich, and Core-Fix fixative samples (Corebiotech) used to fix kidney tissue, after PAS staining. IHC staining showed that CD4 was significantly increased in the lippolysaccharide (LPS)-treated group compared to the control group (vehicle), confirming the changes in specific molecules. The quantity and quality of RNA from tissues fixed in the three types of fixatives were evaluated. The average concentration of RNA was 106 ng/µL and average purity at A 260/280 ratio was 1.7~2.0, regardless of fixative used. For quality of protein, glyceraldehyde 3-phosphate dehydrogenase (GAPDH) protein was confirmed by Western blotting. In conclusion, Core-Fix can be used as a fixative for pathological tissues, in histological and molecular diagnoses.

• The Journal of Fisheries Business Administration
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• v.27 no.1
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• pp.15-45
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• 1996

The sustained economic growth cannot be expected without the balanced development in all the realms of industries. Korea has recorded the continuous high growth rate of economy, but it is now facing some difficulties in keeping the normal economic growth, because industrial workers do not like to work in some fields, the typical one of which is the fishery works. This thesis aims at studying the determinants of fishermen's job satisfaction(FJS) and the determinants of affecting the fishermen's trunover intention(FTI) to obtain and maintain the man power for fishing boats. This study assumes that the determinants which affact FJS are fishermen's work values, job characteristics, the attitude of accepting their fishery work, and that the determinants which affect FTI are FJS and their perceptions of labor market. This study concerns two kinds of Job satisfaction : one is an intrinsic satisfaction which comes directly from the work itself, and the other is an extrinsic satisfaction comes from the compensation for the work, but in this study “Pollnac's work satisfaction factor” is added as an additional determinant of FJS. There is a difference in job satisfactions between the individuals who have different work values. Some feel more satisfacttion than the others, which can be explained by the internal work values which assume the work is only a means for another objective of life. This study applies Hackman and 014ham's studies to the job characteristics that a worker's job satisfaction is positively related to the core job characteristis of the job. In addition, this study transformed their studies into variables. A job enrichment to reduce the simplicity of a work and make it more valueable can increase a job satisfaction, but an existing organization has limitation in redesigning the job for its enrichment. A reasonable answer about this matter can be obtained from the workers' subjective perceptins to highly regard the objective job characteristics. Worker's previews of fishery work also affect their job satisfaction because they are already informed of the details and charcteristics of the job that they have to carry out. A Job dissatisfaction causes their intention to leave jobs owing to general perceptions prevailing in labor markets.