• KSCE Journal of Civil and Environmental Engineering Research
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• v.14 no.2
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• pp.355-365
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• 1994

An analytical model of return flow is presented outside the surf zone. The governing equation is derived from the Navier-Stokes equation and the continuity. Each term of the governing equation is evaluated by the ordering analysis. Then the infinitesimal terms, i.e. the turbulent normal stress, the squared vertical velocity of water particle and the streaming velocity, are neglected. The driving forces of return flow are calculated using the linear wave theory for the shallow water approximation. Especially, the space derivative of local wave heights is described considering a shoaling coefficient. The vertical distribution of eddy viscosity is discussed to the customary types which are the constant, the linear function and the exponential function. Each coefficient of the eddy viscosities which sensitively affect the precision of solutions is uniquely decided from the additional boundary condition which the velocity becomes zero at the wave trough level. Also the boundary conditions at the bottom and the continuity relation are used in the integration of the governing equation. The theoretical solutions of present model are compared with the various experimental results. The solutions show a good agreement with the experimental results in the case of constant or exponential function type eddy viscosity.

• Economic and Environmental Geology
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• v.36 no.3
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• pp.213-223
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• 2003

We estimated the Moho depth of Korean Peninsula from gravity anomalies and digital elevation model. The satellite radar altimetry-derived global free-air gravity model was used to ensure the homogeneity in both data and frequency domains of the original data. Two different methods were implemented to calculate the Moho depth; the wavenumber correlation analysis (Kim et al., 2000a) and the power spectrum analysis. The former method calculates depth-to-the-Moho by correlating topographic gravity effect with free-air gravity anomaly in the wavenumber domain under the assumption that the study area is not isostatically compensated. The latter one, on the other hand, considers the different density layers (i.e., Conrad and Moho), using complete Bouguer gravity anomaly in the Frequency domain of the Fourier transform. The correlation coefficient of the two Moho model is 0.53, and methodology and numerical error are mainly responsible for any mismatch between the two models. In order to integrate the two independentely-estimated models, we applied least-squares adjustment using the differenced depth. The resultant model has mean and standard deviation Moho depths of 32.0 km and 2.5 km with (min, max) depths of (20.3, 36.6) kms. Although this result does not include any topographic gravity effect, however, the validity of isostasy and the role of local stress field in the study area should be further studied.

• Journal of Korean society of Dental Hygiene
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• v.3 no.1
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• pp.59-72
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• 2003

The purpose of this study was to examine what the role of denial hygienist was. The subjects were 751 dental hygienists from dental clinics, dental hospitals, general hospitals, public dental clinics and their branches throughout the nation. After a survey was conducted, the collected data were analyzed with SPSS WIN 10.0, and variance analysis and post-analysis were implemented. And Forgarty's 8th integrated model, out of 10 ones, was selected to delve into the practical role of dental hygienist in detail. The findings of this study were as follows: 1. The three age groups had a significantly different opinion on the significance of individual subjects. The dental hygienists of thirty six and over found the basic and preventive public dental care courses most important, and the 31~35 age group placed most stock in education and research. Overall, the post-analysis results showed that prevention and clinical courses were considered most vital, followed by education and fundamental courses. 2. There was a significant gap between four groups from the different work places in their view of the weight of the individual subjects. According to the post-analysis, the dental hygienists from the general hospitals, public dental clinics and their branches gave more weight to fundamental, education and research areas. Those who were with the dental clinics, dental hospitals and general hospitals put higher value on clinical course than the dental hygienists from the public dental clinics and their branches. 3. Two groups with a different career also had a different outlook on the importance of the individual subjects. The post-analysis results illustrated that the dental hygienists who had worked for three years or more put higher stress on the fundamental course than those with a less career, and the dental hygienists with a five-year or higher career attached more importance to the education and research field than those with a smaller career. 4. There was a significant difference between the three age groups in their clinical role. The post-analysis results indicated thai the younger dental hygienists were more of assistants than of professionals, as they chiefly took X-ray photograph, handled treatment materials or performed treatment-related works. Overall, handling treatment materials was most common. 5. The three groups from the different work places significantly varied in their clinical role. According to the post-analysis, those from the dental clinics and dental hospitals took more x-ray photographs, handled more treatment materials and performed more relevant works, compared to those from the general hospitals, public dental clinics and their branches. 6. The two groups with a different career differed significantly in their clinical role. The post-analysis results suggested that the dental hygienists with a less career played an assistant role more, which handled treatment materials or carried out other relevant works. 7. The fundamental courses (I) and (II), preventive class (I) and (II) and its practice course were regarded as integrated subjects that they should take 10 offer preventive treatment, which was one of the dental hygienist missions. What's needed to act as dental-care educators was the basic courses (I) and (II), dental hygiene education and its practice. Finally, integrated clinical courses (I) and (II) and clinical practice were viewed as necessary for their role performance as dental treatment collaborators.

• Management & Information Systems Review
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• v.36 no.4
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• pp.149-166
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• 2017

The purpose of this study puts stress on effects of job satisfaction and organizational commitment depending on the type of organizational culture of ICT enterprises. This study utilized the 6th Human Capital Corporate Panel(HCCP) data from Korea Research Institute for Vocational Education & Training to analyze the effects of organizational culture in ICT enterprises on the job satisfaction and organizational commitment. The Samples are managers, supervisor, and employees in ICT industries who replied thorough the 6th HCCP. Answers from 875 people, except inappropriate answers, were used to test a hypothesis. In order to do that, reliability analysis and correlation analysis and regression analysis, utilizing the SPSS 24.0 & Amos 18.0, were used to analyze the effects of organizational culture on the job satisfaction and organizational commitment in ICT enterprises. With the purpose of this study, organizational cultures in ICT enterprises have different effects on job satisfaction and organizational commitment. The group culture, development culture, rational culture and hierarchy culture have a positive effects on job satisfaction. And the group culture, development culture and rational culture have a positive effects on organizational commitment. Whereas, hierarchy culture have no effects on organizational commitment. Also, job satisfaction have a positive effects on organizational commitment. Among four cultures of ICT enterprises, the importance of group culture should be stressed. According to the result of empirical analysis, group culture has the most positive impact on job satisfaction, contrary to the expectation that development culture might be the one. So far, the group culture, which emphasizes organizational flexibility, integration, trust, teamwork, high participation, royalty and morale, have positive impact on the organizational employees the most.

• Korean Journal of Soil Science and Fertilizer
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• v.37 no.4
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• pp.266-287
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• 2004

The non infecting, plant associated bacteria have attracted increased attention for stimulating plant growth and as environmental friendly plant protecting agents. Pink-pigmented facultatively methylotrophic bacteria (PPFMs), classified as Methylobacterium spp., are persistent colonizers of plant leaf surfaces. As the leaves of most or all plants harbor PPFMs that utilize leaf methanol as their sole source of carbon and energy, which is a specific attribute of the genus Methylobacterium. Although they are not well known, these bacteria are co-evolved, interacting partners in plant metabolism. This claim is supported, for example, by the following observations: (1) PPFMs are seed-transmitted, (2) PPFMs are frequently found in putatively axenic cell cultures, (3) Low numbers of seed-borne PPFMs correlate with low germinability, (4) Plants with reduced numbers of PPFM show elevated shoot/root ratios, (5) Foliar application of PPFMs to soybean during pod fill enhances seed set and yield, (6) Liverwort tissue in culture requires PPFM-produced vitamin B12 for growth, (7) treated plants to suppress or decrease disease incidence of sheath blight caused by Rhizoctonia solani in rice, and (8) the PPFM inoculation induced number of stomata, chlorophyll concentration and malic acid content, they led to increased photosynthetic activity. Methylobacterium spp. are bacterial symbionts of plants, shown previously to participate in plant metabolism by consuming plant waste products and producing metabolites useful to the plant. There are reports that inform about the beneficial interactions between this group of bacteria and plants. Screening of such kind of bacteria having immense plant growth promoting activities like nitrogen fixation, phytohormone production, alleviating water stress to the plants can be successfully isolated and characterized and integration of such kind of organism in crop production will lead to increased productivity.

• The Bulletin of The Korean Astronomical Society
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• v.35 no.1
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• pp.40.1-40.1
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• 2010

The Main payload of the STSAT-3 (Korea Science & Technology Satellite-3), MIRIS (Multipurpose Infra-Red Imaging System) has been developed for last 3 years by KASI, and its Flight Model (FM) is now being developed as the final stage. All optical lenses and the opto-mechanical components of the FM have been completely fabricated with slight modifications that have been made to some components based on the Engineering Qualification Model (EQM) performances. The components of the telescope have been assembled and the test results show its optical performances are acceptable for required specifications in visual wavelength (@633 nm) at room temperature. The ensuing focal plane integration and focus test will be made soon using the vacuum chamber. The MIRIS mechanical structure of the EQM has been modified to develop FM according to the performance and environment test results. The filter-wheel module in the cryostat was newly designed with Finite Element Analysis (FEM) in order to compensate for the vibration stress in the launching conditions. Surface finishing of all components were also modified to implement the thermal model for the passive cooling technique. The FM electronics design has been completed for final fabrication process. Some minor modifications of the electronics boards were made based on EQM test performances. The ground calibration tests of MIRIS FM will be made with the science grade Teledyne PICNIC IR-array.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.13
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• pp.5271-5276
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• 2014

Mitogen-activated protein kinase/extracellular signal-regulated kinase kinase kinase 3 (MEKK3) is an important protein kinase and a member of the MAPK family, which regulates cellular responses to environmental stress and serves as key integration points along the signal transduction cascade that not only link diverse extracellular stimuli to subsequent signaling molecules but also amplify the initiating signals to ultimately activate effector molecules and induce cell proliferation, differentiation and survival. To explore the relationship between MEKK3 and cell apoptosis, clinicopathology and prognosis, we characterize the expression of MEKK3 and survivin in cervical cancer. MEKK3 and survivin expression was measured by RT-PCR and Western blotting of fresh surgical resections from 30 cases of cervical cancer and 25 cases of chronic cervicitis. Protein expression was detected by tissue microarray and immunochemistry (En Vision) in 107 cases of cervical cancer, 86 cases of cervical intraepithelial neoplasia (CIN), and 35 cases of chronic cervicitis. Expression patterns were analyzed for their association with clinicopathological factors and prognosis in cervical cancer. Expression of MEKK3 and survivin mRNA was significantly higher in cervical cancer than in the controls (p<0.05). MEKK3 and survivin expression differed significantly between cervical carcinoma, CIN, and cervicitis (p<0.05) and correlated with clinical stage, infiltration depth, and lymph node metastasis (p<0.05). MEKK3 expression was positively correlated with survivin (p<0.05). Kaplan-Meier survival analysis showed that MEKK3 and survivin expression, lymph node metastasis, depth of invasion, and FIGO stage reduce cumulative survival. Cox multivariate regression analysis showed that MEKK3, survivin, and clinical staging are independent prognostic factors in cervical cancer (p<0.05). Expression of MEKK3 and survivin are significantly increased in cervical cancer, their overexpression participating in the occurrence and development of cervical cancer, with protein expression and clinical staging acting as independent prognostic factors for patients with cervical cancer.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.10
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• pp.222-230
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• 2020

This study verified the effect size of related factors through meta-analysis based on master's theses and doctoral dissertations and academic journal papers studied in Korea for the past 10years in relation to the resilience of childcare teachers. The verification results are as follows. First, the overall effect size of the protection factors was large. In addition, the personality factor group was the largest among the protection factor groups, followed by the job characteristic factor group and the organizational attribute factor group. Second, among the protection factors, all the sub-factors except the organizational characteristic factor group-ledger leadership and job characteristic factor group-emotional labor, which showed the medium effect size, showed a large effect size. Third, the overall effect size of the risk factor showed a large effect size. The organizational characteristic factor group-burnout showed a larger effect size than the job characteristic factor group-job stress. In conclusion, this study is meaningful in that it attempted a quantitative integration to examine objective results by integrating the previous studies in relation to the resilience of childcare teachers over the past 20 years. In addition, it is significant that it provided basic data for the development of policies and policy developments to improve the resilience of childcare teachers.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.327.1-327.1
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• 2014

Nitrides-on-silicon structures are considered to be an excellent candidate for unique design architectures and creating devices for high-power applications. Therefore, a lot of effort has been concentrating on growing high-quality III-nitrides on Si substrates, mostly Si(111) and Si(001) substrates. However, there are several fundamental problems in the growth of nitride compound semiconductors on silicon. First, the large difference in lattice constants and thermal expansion coefficients will lead to misfit dislocation and stress in the epitaxial films. Second, the growth of polar compounds on a non-polar substrate can lead to antiphase domains or other defective structures. Even though the lattice mismatches are reached to 16.9 % to GaN and 19 % to AlN and a number of dislocations are originated, Si(111) has been selected as the substrate for the epitaxial growth of nitrides because it is always favored due to its three-fold symmetry at the surface, which gives a good rotational matching for the six-fold symmetry of the wurtzite structure of nitrides. Also, Si(001) has been used for the growth of nitrides due to a possible integration of nitride devices with silicon technology despite a four-fold symmetry and a surface reconstruction. Moreover, Si(110), one of surface orientations used in the silicon technology, begins to attract attention as a substrate for the epitaxial growth of nitrides due to an interesting interface structure. In this system, the close lattice match along the [-1100]AlN/[001]Si direction promotes the faster growth along a particular crystal orientation. However, there are insufficient until now on the studies for the growth of nitride compound semiconductors on Si(110) substrate from a microstructural point of view. In this work, the microstructural properties of nitride thin layers grown on Si(110) have been characterized using various TEM techniques. The main purpose of this study was to understand the atomic structure and the strain behavior of III-nitrides grown on Si(110) substrate by molecular beam epitaxy (MBE). Insight gained at the microscopic level regarding how thin layer grows at the interface is essential for the growth of high quality thin films for various applications.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.12
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• pp.614-621
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• 2019

A generalized laminated composite beam element is presented for the flexural and buckling analysis of laminated composite beams with double and single symmetric cross-sections. Based on shear-deformable beam theory, the present beam model accounts for transverse shear and warping deformations, as well as all coupling terms caused by material anisotropy. The plane stress and plane strain assumptions were used along with the cross-sectional stiffness coefficients obtained from the analytical technique for different cross-sections. Two types of one-dimensional beam elements with seven degrees-of-freedom per node, including warping deformation, i.e., three-node and four-node elements, are proposed to predict the flexural behavior of symmetric or anti-symmetric laminated beams. To alleviate the shear-locking problem, a reduced integration scheme was employed in this study. The buckling load of laminated composite beams under axial compression was then calculated using the derived geometric block stiffness. To demonstrate the accuracy and efficiency of the proposed beam elements, the results based on three-node beam element were compared with those of other researchers and ABAQUS finite elements. The effects of coupling and shear deformation, support conditions, load forms, span-to-height ratio, lamination architecture on the flexural response, and buckling load of composite beams were investigated. The convergence of two different beam elements was also performed.