• Journal of Korean Tunnelling and Underground Space Association
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• v.19 no.2
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• pp.249-263
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• 2017

The expansion behavior of inflatable steel pipe rockbolt shows geometric nonlinearity due to its ${\Omega}-shaped$ section. Previous studies on the anchoring behavior of inflatable steel pipe rockbolt were mainly performed using theoretical method. However, those studies oversimplified the actual behavior by assuming isotropic expansion of inflatable steel pipe rockbolt. In this study, the anchoring behavior of the inflatable steel pipe rockbolt were investigated by the numerical method considering the irregularity of pipe expansion and other influencing factors. The expansion of inflatable steel pipe rockbolt, the contact stress distribution and the change of the average contact stress and the contact area during installation were analyzed. The contact stresses were developed differently depending on the constitutive behavior of rocks. Small contact stresses occurred in steel pipes installed in elasto-plastic rock compared to steel pipes installed in elastic rock. Also, the anchoring behaviors of the inflatable steel pipe rockbolt were different according to the stiffness of the rock. The steel pipe was completely unfolded in the case of the stiffness smaller than 0.5 GPa, but it was not fully unfolded in the case of the stiffness larger than 0.5 GPa for the given analysis condition. When the steel pipe is completely unfolded, the contact stress increases as the rock stiffness increases. However, the contact stress decreases as the rock stiffness increases when the steel pipe is not fully expanded.

• Solar Energy
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• v.17 no.4
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• pp.3-11
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• 1997

Because grain boundaries in polycrystalline silicon act as potential barriers and recombination centers for the photo-generated charge carriers, these defects degrade conversion effiency of solar cell. To reduce these effects of grain boundaries, we investigated various influencing factors such as thermal treatment, various grid pattern, selective wet etching for grain boundaries, buried contact metallization along grain boundaries, grid on metallic thin film. Pretreatment above $900^{\circ}C$ in $N_2$ atmosphere, gettering by $POCl_3$ and Al treatment for back surface field contributed to obtain a high quality poly-Si. To prevent carrier losses at the grain boundaries, we carried out surface treatment using Schimmel etchant. This etchant delineated grain boundaries of $10{\mu}m$ depth as well as surface texturing effect. A metal AI diffusion into grain boundaries on rear side reduced back surface recombination effects at grain boundaries. A combination of fine grid with finger spacing of 0.4mm and buried electrode along grain boundaries improved short circuit current density of solar cell. A ultra-thin Chromium layer of 20nm with transmittance of 80% reduced series resistance. This paper focused on the grain boundary effect for terrestrial applications of solar cells with low cost, large area, and high efficiency.

• Korean Journal of Bronchoesophagology
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• v.7 no.1
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• pp.29-33
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• 2001

Background and Objectives： Adenoid cystic carcinoma (ACC) is an aggressive, often indolent tumor, with a high incidence of distant metastasis (DM). Relatively little has been written about the factor that influence distant spread and subsequent survival because it is uncommon and has protracted clinical course. We attempted to reemphasize the biologic behavior of ACC by investigating the relationship between the clinical features and prognosis. Materials and Methods : We have retrospectively studied 24 determinate patiens who received definitive treatment in our hospital between 1984 and 1995 for ACC in all salivary sites. Inclusion criteria were no prior treatment elsewhere other than excisional biopsy and eligibility for follow-up of at least 5 years. Variables assessed for their impact on distant metastasis included age, gender, size, node status, stage, histologic pattern, locoregional treatment failure. Results : Treatment failure occurred in a total of 16 of 24 determinate Patients (64%), 12 of whom had DM (50%). This was usually associated with locoregional recurrence (8 patients), but DM was the only indication of failure in 4 whose primary tumor was controlled. Of the 12 patients with known DM, the lung was recored as the only involved site in 7 Patients, lung was involved in addition to other sites in 1, bone and liver metastasis occurred in 2 respectively. Disease-free intervals varied from 3 month to 14 years (median 3 years). The only significant factors influencing survival were the size of the primary tumor, locoregional recurrence. Conclusion : The high incidence of DM with locoregional failure confirms the importance of aggressive initial surgery. combined with irradiation, for high-stage tumors or involved surgical margins. Large tumor size and locoregional recurrence, rather than microscopic appearance, were predictive of DM.

• Journal of Digital Convergence
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• v.16 no.7
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• pp.419-428
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• 2018

Purpose: The study was done to investigate the correlation among health literacy, social support and medication adherence in elderly with chronic diseases. Method: Participants were 100 patients with chronic diseases in two small hospitals in J do H. A structured questionnaires was used to measure the study variables from July 14, 2017 to August 14, 2017. Data was analyzed using descriptive statistics, t-test, ANOVA, Spearman correlation coefficient, and Multiple regression by SPSS/WIN 18.0 program. Result: Medication adherence and health literacy were positively correlated(r=.398, p<.001), Medication adherence and social support were positively correlated (r=.453, p<.001) and health literacy and social support were positively correlated(r=.731, p<.001). The factors influencing on medication adherance are Experience of adverse drug effect. The explanation is that medication adherence is total 25.9%(F=3.91, p<.001). Conclusion: Thus this suggests that in order to enhance medication adherence of the elderly with chronic diseases, educational programs are needed for offering customized medical information considering unique characteristics of the area and objects.

• Korean Journal of Environment and Ecology
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• v.30 no.5
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• pp.810-820
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• 2016

This study is focused on the investigation of the genes which are induced by various stresses of the halophyte Salicornia herbacea. One of the factors influencing in the germination of Salicornia herbacea is salt stress. The highest germination rate was found in the condition without NaCl, and the upper limit of the NaCl concentration for the germination of Salicornia herbacea was 7%. The optimal temperature of $20^{\circ}C$showed a germination rate of 98%. Among genes induced by stress the 2CysPrx gene was cloned and analyzed for this study. The 2CysPrx gene has two cysteine conserved residues and is composed of 275 amino acids with molecular weight of 30.1kDa. The 2CysPrx gene appeared to be one copy in the genome and consists of 6 introns and 7 exons. Quantitative real-time PCR revealed that the highest transcription rate induced by NaCl and $H_2O_2$ appeared to be at the concentration of 3.5% NaCl and 40mM $H_2O_2$, respectively. The amount of transcript induced by high temperature($40^{\circ}C$) and $75{\mu}M$ of ABA was respectively highest. The gene at low temperature ($4^{\circ}C$) appeared not to be expressed. We are conducting to clone other peroxyredoxin genes induced by various environmental stresses.

• The Journal of the Convergence on Culture Technology
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• v.6 no.4
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• pp.85-93
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• 2020

This study was conducted to investigate ego resilience, cognitive emotion regulation strategies, academic stress on mental health of nursing students and provide data to increase mental health for nursing students based on the results. This research involved 299 nursing students in B city. The analyzed by the t-test, ANOVA, Pearson's correlation coefficient, multiple regression using SPSS/WIN 22.0. In results of the study, the average of mental health was 3.77±.98. Mental health were positively correlated with ego resilience (r=.450, p<.001), cognitive emotion regulation strategies (r=.408, p<.001), and was negatively correlated with academic stress (r=-.469, p<.001). Regression analysis showed 38.4% of variance in nursing student's the mental health can by experience of dating with age (β=-.171, p=.001), adjustment to college life (β=.223, p<.001), ego resilience (β=.203, p<.001), cognitive emotion regulation strategies (β=.179, p=.001), academic stress (β=-.193, p=.001). The fallow-up survey about various factors influencing nursing student's the mental health increasing program developing are required.

• Survey Research
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• v.11 no.1
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• pp.63-85
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• 2010

This study defines the substance and multi-dimension of emotional reactions which Koreans have toward foreigners to find the starting point of change in values which is an inevitable task in this multi-cultural society. The results indicate that the Bogardus scale which has been used to measure the social distance toward the minority race is found to have limitations in explaining the closed attitude of Koreans toward 'nation' and 'kinship through marriage'. To supplement such limitations, exploration on attitudes toward foreigners from different native places is performed based on the 'evaluation', 'power' and 'activity' dimensions of the Affective Control Theory. As a result, Americans are highly evaluated in all three dimensions while Japanese are evaluated low in the 'evaluation' dimension and high in the 'power' and 'activity' dimensions. North Korean defectors and ethnic Koreans from China (the Chosun race) are high in evaluation but low in other dimensions. West Asians are evaluated low in all three dimensions. By comprehending the influencing factors and the relative influence of social distance, it proves that the 'evaluation' dimension is the common denominator in all groups while 'power' dimension toward Japanese and 'activity' dimensions toward Chinese and West Asians influence social distance. All foreigners excluding Americans receive closer social distance when having higher education level. Moreover, American women and older North Korean defectors receive closer social distance.

• Journal of Periodontal and Implant Science
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• v.36 no.2
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• pp.531-554
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• 2006

Oral implants must fulfill certain criteria arising from special demands of function, which include biocompatibility, adequate mechanical strength, optimum soft and hard tissue integration, and transmission of functional forces to bone within physiological limits. And one of the critical elements influencing the long-term uncompromise functioning of oral implants is load distribution at the implant- bone interface, Factors that affect the load transfer at the bone-implant interface include the type of loading, material properties of the implant and prosthesis, implant geometry, surface structure, quality and quantity of the surrounding bone, and nature of the bone-implant interface. To understand the biomechanical behavior of dental implants, validation of stress and strain measurements is required. The finite element analysis (FEA) has been applied to the dental implant field to predict stress distribution patterns in the implant-bone interface by comparison of various implant designs. This method offers the advantage of solving complex structural problems by dividing them into smaller and simpler interrelated sections by using mathematical techniques. The purpose of this study was to evaluate the stresses induced around the implants in bone using FEA, A 3D FEA computer software (SOLIDWORKS 2004, DASSO SYSTEM, France) was used for the analysis of clinical simulations. Two types (external and internal) of implants of 4.1 mm diameter, 12.0 mm length were buried in 4 types of bone modeled. Vertical and oblique forces of lOON were applied on the center of the abutment, and the values of von Mises equivalent stress at the implant-bone interface were computed. The results showed that von Mises stresses at the marginal. bone were higher under oblique load than under vertical load, and the stresses were higher at the lingual marginal bone than at the buccal marginal bone under oblique load. Under vertical and oblique load, the stress in type I, II, III bone was found to be the highest at the marginal bone and the lowest at the bone around apical portions of implant. Higher stresses occurred at the top of the crestal region and lower stresses occurred near the tip of the implant with greater thickness of the cortical shell while high stresses surrounded the fixture apex for type N. The stresses in the crestal region were higher in Model 2 than in Model 1, the stresses near the tip of the implant were higher in Model 1 than Model 2, and Model 2 showed more effective stress distribution than Model.

• Journal of Periodontal and Implant Science
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• v.35 no.3
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• pp.761-776
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• 2005

The purpose of the present study was to examine the relationship between the form of the clinical crowns in the maxillary anterior segment and the clinical feature of gingiva such as morphological characteristics and the gingival thickness. Fifty periodontally healthy subjects were clinically examined regarding the probing depth, the thickness of the free gingiva, and the width of the keratinized gingiva. From study models of the maxillary anterior region, the width at cervical third(CW) and the length(CL) of the clinical crown, the papillary height, and the gingival angle of the 6 anterior teeth were measured. Each tooth was classified into 4 groups (longnarrow, NL; narrow, N; wide, W; short-wide, WS) according to CW/CL ratio and all the data were compared between groups NL and WS using independent t-test. Stepwise multiple regression analysis was performed for each tooth region with the gingival thickness at the level of sulcus bottom, the width of keratinized gingiva, and gingival angle as the dependent variables. As the results, the NL group of the upper anterior teeth displayed, higher papilla height, and narrower keratinized gingiva, more acute gingival angle resulting in pronounced "scalloped" contour of the gingival margin, compared to the WS group. There was no significant difference between groups NL and WS with respect to probing depth and the gingival thickness. The regression analyses demonstrated that the gingival thickness in central incisors was significantly associated to the mesio-distal width and bucco-lingual width of the crown, and labial probing depth. The width of keratinized gingiva was significantly associated with labial probing depth in central incisors and with proximal probing depth and gingival angle in lateral incisors, and with labial and proximal probing depth, and gingival angle in canines. The gingival angle was significantly associated with papillary height and CW/CL ratio and additionally with proximal probing depth in central incisors, with the width of keratinized gingiva in lateral incisors, and with labial probing depth and the width of keratinized gingiva in canines. These results indicate that the form of clinical crown in upper anterior region could influence the clinical feature of gingiva and the influencing factors might be different according to the tooth region.

• Culinary science and hospitality research
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• v.17 no.5
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• pp.57-73
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• 2011

This study was conducted to examine the overall perception of importance and possibility of Korean food and globalization of Korean food. Analyzing the factors influencing globalization of Korean food, this study suggests development strategies and basic data for globalization of Korean food and development of high skilled manpower. The survey was carried out from April 1, 2011 to April 30, 2011, targeting students majoring in foodservice, who will play a key role in globalization of Korean Food. Analysis methods included frequency analysis, descriptive statistics, t-test, ANOVA, factor analysis, correlation analysis, and multiple regression analysis. The findings are summarized as follows: (1) Students recognized Korean food as a nutritionally balanced healthy food. (2) Standardization of Korean cuisine and food names was the most important. (3) Students were very interested in globalization of Korean Food. (4) Perception of Korean food and its globalization were significantly different according to the levels of education. (5) As a result of analyzing the effect on globalization, quality and healthfulness of Korean food had a positive effect on globalization of Korean food.