• The Journal of Advanced Prosthodontics
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• v.5 no.4
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• pp.464-470
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• 2013

PURPOSE. The aim of this Fourier transform infrared (FTIR) spectroscopic study was to measure the degree of conversion (DC) of dual-cured resin cements light-irradiated through zirconia ceramic disks with different thicknesses using various light-curing methods. MATERIALS AND METHODS. Zirconia ceramic disks (KT12) with three different thicknesses (1.0, 2.0, and 4.0 mm) were prepared. The light transmittance of the disks was measured using ultraviolet visible near-infrared spectroscopy. Four different light-curing protocols were used by combining two curing light modes (Elipar TriLight (standard mode) and bluephase G2 (high power mode)) with light-exposure times of 40 and 120 seconds. The DCs of the two dual-cured resin cements (Duo-Link and Panavia F2.0) light-irradiated through the disks was analyzed at three time intervals (3, 7, and 10 minutes) by FTIR spectroscopy. The data was analyzed using repeated measures ANOVA (${\alpha}$=.05).Two-way ANOVA and Tukey post hoc test were used to analyze the 10 minute DC results. RESULTS. The 1.0 mm thick disk exhibited low light transmittance (<25%), and the transmittance decreased considerably with increasing disk thickness. All groups exhibited significantly higher 10 minute DC values than the 3 or 7 minute values (P<.05), but some exceptions were observed in Duo-Link. Two-way ANOVA revealed that the influence of the zirconia disk thickness on the 10 minute DC was dependent on the light-curing methods (P<.001). This finding was still valid even at 4.0 mm thickness, where substantial light attenuation took place. CONCLUSION. The curing of the dual-cured resin cements was affected significantly by the light-curing technique, even though the additional chemical polymerization mechanism worked effectively.

• Journal of the Korean Home Economics Association
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• v.28 no.3
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• pp.13-24
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• 1990

The main purpose of this study are as follows ; 1) To examine closely the effect of personality dimension on brand image. 2) To investigate the difference of variables about brand image according to the characteristics of the population statistics and draw the strategies of marketing for our wear enterprises. A 300 Samples were selected from female in Seoul and the investigation was conducted during 21 days, from 1998. 9. 21 to 1988. 10. 11. As for survey methozs, the personality dimension test developed by Eysenk was adopted. To measure the brand image, the adjectives of the semantic differentia scale developed by Malhotra and adjective that has been used in various were image analysis were adopted. The data were analysed using the statistical technic of Correlation Coefficient, F-test, and X2 test. The Results obtained from this study were as follows. 1. There were partially significant relationships between adult female's four subordinate variables of the personality dimension and preferred brand image on Women's ready-made wear. 1) The people having a high Psychoticism tendency preferred "individual" image and less preferred "practical" image than the people of low Psychoticism. 2) The people having a high extraversion tendency preferred "bold", "aged" image and less preferred "feminine", "practical" image. 3) The unstable female having a high neuroticism tendency preferred "abscure" image and less preferred "Practical" "gaudy", "Open hearted" image. 4) The people having a high lie tendency perferred "intricate", "classical" image and less preferred "bold", "citified", "incongruous" image. 2. There were partially significant differences in adult female's preferred brand image on women's ready made wear according to the characteristics of the population statistics.

• Journal of Korean Academy of Nursing
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• v.24 no.4
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• pp.529-544
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• 1994

For most parents their child's illness and hospitalization is strssful. Internal stress and over anxiousness leads to uncertainty. Parents have a variety of ways of coping when faced with such stress factors, especialy when the child has cancer. The purpose of this study was to examine the relationship between uncertainty in illness and mastery and coping styles in parents of pediatric cancer patients, and further to identify differences between three groups of subjects. A cross-sectional descriptive correlational design was used in this study to investigate the relationship among the three groups. The sample was composed of 59 parents of children with cancer in pediatric wards in three hospitals in Seoul : 21 in Group 4 with a child newly diagnosed with cancer : 25 in Group B, with a child under treatment and rehospitalized with a relapse : and 13 in Group C, with a child with a terminal cancer, A formalized questionnaire which included demegrapic information and consisted of 75 items was used in this study ; The Parent Perception of Uncertainty Scale(PPUS) adapted form Mishel’s Uncertainty in Illness Scale, Pearlin & Schooler's Mastery Scale(MS) and Folkman & Lazarus’s Ways of Coping Checklist(WCC) were used to measure the variables : uncertainty in illness, mastery, and coping styles. A pretest was conducted on the questionnaire items for reliability. The results gathered were analyzed using SPSS /PC/sup +/. Data analysis included descriptive correltional statistics such as ANOVA, Pearson Correlation Coefficient, amd chi square test. The conclusions of this analysis are summarized as follows : 1. A higher level of uncertainty was seen among parents of children with terminal cancer. 2. The first hypothesis that uncertainty in illness would differ among the three groups was supported(F=4.182, P=.020). The second and third hypotheses that mastery and coping styles would differ among the three groups were not supported. There was a correlation between uncertainty, mastery, and coping styles which was positive, also there was a positive correlation between mastery and coping style(r=.3744, P<.001) but a negative correlation between uncertainty md mastery(r=-.4749, P<.01). From the above results, it can be concluded that prediciting and controlling uncertainty in illness by considering coping styles and mastery are necessary for improved, efficient nursing interventions.

• Journal of the Korean Data and Information Science Society
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• v.21 no.3
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• pp.387-395
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• 2010

It is important to identify the interaction of genes about human disease and characteristic value. Many studies as like logistic analysis, have associated being pursued, but, previous methods did not consider the sub-group of the genotypes. So, QTL interactions and the GMM (genotype matrix mapping) have been developed. In this study, we detect the superior genotype combination to have an impact on economic traits of Korean cattle based on the study over GMM method. Thus, we identified interaction effects of single nucleotide polymorphisms (SNPs) responsible for average daily gain(ADG), marbling score (MS), carcass cold weight (CWT), longissimus muscle dorsiarea (LMA) using GMM method. In addition, we examine significance of the major genotype combination selected by implementing permutation test of the F-measure which was not obtained by Sachiko et al.

• Transactions on Electrical and Electronic Materials
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• v.11 no.3
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• pp.120-125
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• 2010

For the fabrication of PMOS and integrated semiconductor devices, B, $BF_2$ and dual elements with B and $BF_2$ can be implanted in silicon. 15 keV B ions were implanted in silicon at $7^{\circ}$ wafer tilt and a dose of $3.0{\times}10^{16}\;cm^{-2}$. 67 keV $BF_2$ ions were implanted in silicon at $7^{\circ}$ wafer tilt and a dose of $3.0{\times}10^{15}\;cm^{-2}$. For dual implantations, 67 keV $BF_2$ and 15keV B were carried out with two implantations with dose of $1.5{\times}10^{15}\;cm^{-2}$ instead of $3.0{\times}10^{15}\;cm^{-2}$, respectively. For the electrical activation, the implanted samples were annealed with rapid thermal annealing at $1,050^{\circ}C$ for 30 seconds. The implanted profiles were characterized by using secondary ion mass spectrometry in order to measure profiles. The implanted and annealed results show that concentration profiles for the ${BF_2}^+$ implant are shallower than those for a single $B^+$ and dual ($B^+$ and ${BF_2}^+$) implants in silicon. This effect was caused by the presence of fluorine which traps interstitial silicon and ${BF_2}^+$ implants have lower diffusion effect than a single and dual implantation cases. For the fabricated diodes, current-voltage (I-V) and capacitance-voltage (C-V) were also measured with HP curve tracer and C-V plotter. Electrical measurements showed that the dual implant had the best result in comparison with the other two cases for the turn on voltage characteristics.

• International Journal of Concrete Structures and Materials
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• v.9 no.4
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• pp.475-486
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• 2015

Mode II fracture toughness ($K_{IIc}$) of fiber reinforced concrete (FRC) has been widely investigated under various patterns of test specimen geometries. Most of these studies were focused on single type fiber reinforced concrete. There is a lack in such studies for hybrid fiber reinforced concrete. In the current study, an experimental investigation of evaluating mode II fracture toughness ($K_{IIc}$) of hybrid fiber embedded in high strength concrete matrix has been reported. Three different types of fibers; namely steel (S), glass (G), and polypropylene (PP) fibers were mixed together in four hybridization patterns (S/G), (S/PP), (G/PP), (S/G/PP) with constant cumulative volume fraction ($V_f$) of 1.5 %. The concrete matrix properties were kept the same for all hybrid FRC patterns. In an attempt to estimate a fairly accepted value of fracture toughness $K_{IIc}$, four testing geometries and loading types are employed in this investigation. Three different ratios of notch depth to specimen width (a/w) 0.3, 0.4, and 0.5 were implemented in this study. Mode II fracture toughness of concrete $K_{IIc}$ was found to decrease with the increment of a/w ratio for all concretes and test geometries. Mode II fracture toughness $K_{IIc}$ was sensitive to the hybridization patterns of fiber. The (S/PP) hybridization pattern showed higher values than all other patterns, while the (S/G/PP) showed insignificant enhancement on mode II fracture toughness ($K_{IIc}$). The four point shear test set up reflected the lowest values of mode II fracture toughness $K_{IIc}$ of concrete. The non damage defect concept proved that, double edge notch prism test setup is the most reliable test to measure pure mode II of concrete.

• The Journal of Advanced Prosthodontics
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• v.9 no.1
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• pp.57-66
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• 2017

PURPOSE. Cementation failures of restorations are frequently observed in clinical practice. The purpose of this study is to compare the effect of initial and repeated bonding on the bond strengths of different resin cements to enamel and dentin. MATERIALS AND METHODS. Ninety human maxillary central incisors were bisected longitudinally. The 180 tooth halves were divided into 2 groups (n = 90) for enamel and dentin bonding. The enamel and dentin groups were further divided into 3 groups (n = 30) for different resin cement types. Composite resin (Filtek Ultimate) cylinders ($3{\times}3\;mm$) were prepared and luted to enamel and dentin using Variolink II (Group V), RelyX ARC (Group R), or Panavia F 2.0 (Group P) resin cement. After 24 hours, initial shear bond strengths of the resin cements to enamel and dentin were measured. Using new cylinders, the specimens were de-bonded and re-bonded twice to measure the first and the second bond strengths to enamel and dentin. Failure modes and bonding interfaces were examined. Data were statistically analyzed. RESULTS. Initial and repeated bond strengths to enamel were similar for all the groups. The first ($15.3{\pm}2.2\;MPa$) and second ($10.4{\pm}2.2\;MPa$) bond strengths to dentin were significantly higher in Group V (P<.0001). Second bond strengths of dentin groups were significantly lower than initial and first bond strengths to dentin (P<.0001). CONCLUSION. All resin cements have similar initial and repeated bond strengths to enamel. Variolink II has the highest first and second bond strength to dentin. Bond strength to dentin decreases after the first re-bonding for all resin cements.

• The Mathematical Education
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• v.44 no.2 s.109
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• pp.307-323
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• 2005

The purpose of this study was to develop a program to cultivate mathematical creativity based on open-ended problem and to investigate its effect. The major features of this innovative program are (a) breaking up fixations, (b) multiple answers, (c) various strategies, (d) problem posing, (e) exploring strategies, (f) selecting and estimating, (g) active exploration through open-ended problems. 20 units for 7th grade mathematics were developed. This study hypothesizes that experimental students may develop more divergent thinking abilities than their traditional counterparts. The participants were 7th grade students attending middle schools in Seoul. Instruments were pre and post tests to measure mainly divergent thinking skills through open-ended problems. The results indicated that the experimental students achieved better than the comparison students on overall and each component of fluency, flexibility, and originality of divergent thinking skills, when deleting the effect of covariance of the pretest. The developed program can be a useful resource for teachers to use in enhancing their students' creative thinking skills. Further this open-ended approach can be served as a model to implement in classes. This study suggests that further investigations are needed in order to examine effects on affective domains such as motivation and task perseverance which are also considered as important factors of creativity.

• Korean Journal of Food Science and Technology
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• v.25 no.4
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• pp.299-306
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• 1993

Determination of dietary fiber contents in some Korean foods was attempted by Englyst's gas chromatographic and colorimetric methods which measure the nonstarch polysaccharide (NSP) contents NSP values, except seaweeds, by gas chromatography (x) and colorimetry (y) were very closely correlated (y=1.01x-0.52, r=0.997, n=9), NSP values by gas chromatography were lower than total dietary fiber (TDF) Haloes by AOAC method. By adding lignin to NSP values, relation between the two methods was improved. But, TDF values (y) by adding lignin to NSP values and TDF values (x) by AOAC method were related as y=0.68x-0.64 and F=0.903(n= 12), which was not closely related.

• Spatial Information Research
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• v.13 no.1 s.32
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• pp.1-17
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• 2005

This paper draws new guidelines on the current method in Land Suitability Assessment (LSA), enforced to identify potential of parcels .elated to agricultural productivity, preservable value, and economic viability. In order to make recommendations of current LSA methodology, this study analyzes the issues related to the parcel-based LSA and addresses its inappropriateness f3r incorporating characteristics of each parcel. Through case studies and sensitivity analyses using GIS, the results show that (1) the $10\times10m$ grid-based LSA is much better assessment method than parcel-based one, because it gives detailed informations on attributes of each parcel; (2) more than one-distance factor should be taken into account to calculate the appropriate potential measure; and (3) the characteristics of public facilities or urbanized areas including size, density, and land use should be incorporated into the attraction variable of ny Potential model. Finally future research areas are outlined.