• Korean Journal of Mathematics
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• v.28 no.3
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• pp.587-601
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• 2020

In this paper we propose a way of enhancing eigenvalue approximations with the Bank-Weiser error estimators for the P1 and P2 conforming finite element methods of the Laplace eigenvalue problem. It is shown that we can achieve two extra orders of convergence than those of the original eigenvalue approximations when the corresponding eigenfunctions are smooth and the underlying triangulations are strongly regular. Some numerical results are presented to demonstrate the accuracy of the enhanced eigenvalue approximations.

• Child Health Nursing Research
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• v.22 no.1
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• pp.45-53
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• 2016

Purpose: The study was done to investigate behavioral problems in toddlers who were born prematurely and to analyze related factors. Methods: A cross-sectional explorative study was conducted with 72 preterm birth (PTB) children at 24 to 41 months of corrected age who were born at 28 to 37 weeks' gestation. During home visits, behavior problems were assessed using the Behavior Rating Index for Children (BRIC). Using a BRIC score of ${\geq}30$, children with suspected behavior problems were grouped in the non-regular behavior group. Results: Of the children, 38.9% belong to the non-regular behavior group. The mental development index score for the Korean-Bayley Scale of Infant Development- II was higher for the non-regular behavior group compared to the regular behavior group (t=2.26, p=.027). Logistic regression analysis showed that lower maternal attachment (<96, OR=3.4, 95% CI[1.1, 10.4]) and higher parenting stress (${\geq}97$, OR=4.8, 95% CI[1.3, 17.3]) were independently related to non-regular behavior. Conclusion: PTB Toddlers are at risk for behavior problems which are associated with low cognitive performance. Maternal-child attachment and maternal parenting stress were strongly related to behavior problems in these children. More attention is needed to understand possible behavior problems in young children with PTB, particularly focusing on maternal-child interaction and maternal mental well-being.

• Bulletin of the Korean Mathematical Society
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• v.52 no.3
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• pp.935-946
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• 2015

The purpose of this paper is to introduce a new class of rings that is closely related to the classes of pseudo valuation rings (PVRs) and pseudo-almost valuation domains (PAVDs). A commutative ring R is said to be ${\phi}$-ring if its nilradical Nil(R) is both prime and comparable with each principal ideal. The name is derived from the natural map ${\phi}$ from the total quotient ring T(R) to R localized at Nil(R). A prime ideal P of a ${\phi}$-ring R is said to be a ${\phi}$-pseudo-strongly prime ideal if, whenever $x,y{\in}R_{Nil(R)}$ and $(xy){\phi}(P){\subseteq}{\phi}(P)$, then there exists an integer $m{\geqslant}1$ such that either $x^m{\in}{\phi}(R)$ or $y^m{\phi}(P){\subseteq}{\phi}(P)$. If each prime ideal of R is a ${\phi}$-pseudo strongly prime ideal, then we say that R is a ${\phi}$-pseudo-almost valuation ring (${\phi}$-PAVR). Among the properties of ${\phi}$-PAVRs, we show that a quasilocal ${\phi}$-ring R with regular maximal ideal M is a ${\phi}$-PAVR if and only if V = (M : M) is a ${\phi}$-almost chained ring with maximal ideal $\sqrt{MV}$. We also investigate the overrings of a ${\phi}$-PAVR.

• The Korean Journal of Community Living Science
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• v.26 no.1
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• pp.39-49
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• 2015

This study evaluates nutrition knowledge, dietary behaviors and food group acceptability based on a sample of 514 of new employees in Gyeonggi area. Among the respondents, 70.6% of male, and their age was 30.7 Most were college graduates (94.9%) and unmarried (86.3%). Based on the BMI males tended to be overweight, whereas females, normal. In terms of health consciousness based on five-point Likert-type scale, the average score for the health status was 4.18 indicating good health, and health attention was 4.88 indicating high health attention. Dietary behaviors were evaluated using five-point Likert-type scale. According to the results, the total score for regular diet based on 5 items was 9.6; that for a balanced diet based on 7 items was 22.2; and that for practical diet action based on 8 items was 22.3. That is, the respondents were on an irregular diet but tried to balanced diet through appropriate diet action. Food acceptability was evaluated using a five-point Likert scale ranging from "strongly dislike(1)" to "strongly like(5)". The score of meat group was 3.67; that for the fish 3.43; and that for the vegetable group was 2.86. Females were slightly more like to accept fruits 3.60 than males 3.48;(p<0.05). The total score for nutrition knowledge based on 35 items was 20.5. A balanced diet was correlated with egg acceptability (p<0.01); energy-related knowledge with confectionery preferences (p<0.05); and vitamin knowledge, with snack affinity (p<0.05). Health attention was negatively correlated with seafood preferences for male(p<0.05) and with snacks for females(p<0.05). The respondents were strongly interested in and aware of their health, but this did not lead to their food preferences. These results suggests that dietary habits can lead to nutritional balance for maintaining the health of employees.

• Communications of the Korean Mathematical Society
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• v.26 no.1
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• pp.135-149
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• 2011

Using (r, s)-preopen sets [14] and pre-${\omega}_t$-closures [6], a new kind of covering property $P^t_{({\omega}_r,s)}$-closedness is introduced in a bitopological space and several characterizations via filter bases, nets and grills [30] along with various properties of such concept are investigated. Two new types of cluster sets, namely pre-(${\omega}_r$, s)t-${\theta}_f$-cluster sets and (r, s)t-${\theta}_f$-precluster sets of functions and multifunctions between two bitopological spaces are introduced. Several properties of pre-(${\omega}_r$, s)t-${\theta}_f$-cluster sets are investigated and using the degeneracy of such cluster sets, some new characterizations of some separation axioms in topological spaces or in bitopological spaces are obtained. A sufficient condition for $P^t_{({\omega}_r,s)}$-closedness has also been established in terms of pre-(${\omega}_r$, s)t-${\theta}_f$-cluster sets.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.12
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• pp.7693-7699
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• 2013

Aims: A main reason for increasing incidence of cervical cancer worldwide is the lack of regular cervical cancer screening. Coverage and uptake remain major challenges and it is crucial to determine the perceived susceptibility to cervical cancer, as well as the benefits of, and barriers to, cervical cancer screening among women. Materials and Methods: A cross-sectional survey was conducted among 369 women attending an outpatient centre in Malaysia and data were collected by administering a self-report questionnaire. Results: The majority of the participants (265, 71.8%) showed good level of perception of their susceptibility to cervical cancer. Almost all responded positively to four statements about the perceived benefits of cervical cancer screening (agree, 23.1% or strongly agree, 52.5%), whereas negative responses were received from most of the participants (agree, 29.9%or strongly agree, 14.6 %) about the eleven statements on perceived barriers. Significant associations were observed between age and perceived susceptibility($x^2$=9.030, p=0.029); between employment status (p<0.001) as well as ethnicity and perceived benefits (p<0.05 [P=0.003]); and between education and perceived barriers to cervical cancer screening (p<0.001). Conclusions: Perceived susceptibility, including knowledge levels and personal risk assessment, should be emphasized through education and awareness campaigns to improve uptake of cervical cancer screening in Malaysia.

• Bulletin of the Korean Mathematical Society
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• v.59 no.3
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• pp.529-545
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• 2022

This article concerns a ring property that arises from combining one-sided duo factor rings and centers. A ring R is called right CIFD if R/I is right duo by some proper ideal I of R such that I is contained in the center of R. We first see that this property is seated between right duo and right π-duo, and not left-right symmetric. We prove, for a right CIFD ring R, that W(R) coincides with the set of all nilpotent elements of R; that R/P is a right duo domain for every minimal prime ideal P of R; that R/W(R) is strongly right bounded; and that every prime ideal of R is maximal if and only if R/W(R) is strongly regular, where W(R) is the Wedderburn radical of R. It is also proved that a ring R is commutative if and only if D₃(R) is right CIFD, where D₃(R) is the ring of 3 by 3 upper triangular matrices over R whose diagonals are equal. Furthermore, we show that the right CIFD property does not pass to polynomial rings, and that the polynomial ring over a ring R is right CIFD if and only if R/I is commutative by a proper ideal I of R contained in the center of R.

• Imaging Science in Dentistry
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• v.49 no.4
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• pp.273-279
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• 2019

Purpose: This study was performed to investigate the effects of energy level, reconstruction kernel, and tube rotation time on Hounsfield unit (HU) values of hydroxyapatite (HA) in virtual monochromatic images (VMIs) obtained with dual-energy computed tomography (DECT)(Siemens Healthineers, Erlangen, Germany). Materials and Methods: A bone density calibration phantom with 3 HA inserts of different densities(CTWATER^®; 0, 100, and 200 mg of HA/㎤) was scanned using a twin-beam DECT scanner at 120 kVp with tube rotation times of 0.5 and 1.0 seconds. The VMIs were reconstructed by changing the energy level (with options of 40 keV, 70 keV, and 140 keV). In order to investigate the impact of the reconstruction kernel, virtual monochromatic images were reconstructed after changing the kernel from body regular 40 (Br40) to head regular 40 (Hr40) in the reconstruction phase. The mean HU value was measured by placing a circular region of interests (ROIs) in the middle of each insert obtained from the VMIs. The HU values were compared with regard to energy level, reconstruction kernel, and tube rotation time. Results: Hydroxyapatite density was strongly correlated with HU values(correlation coefficient=0.678, P<0.05). For the HA 100 and 200 inserts, HU decreased significantly at increased energy levels(correlation coefficient= -0.538, P<0.05) but increased by 70 HU when using Hr40 rather than Br40 (correlation coefficient=0.158, P<0.05). The tube rotation time did not significantly affect the HU(P>0.05). Conclusion: The HU values of hydroxyapatite were strongly correlated with hydroxyapatite density and energy level in VMIs obtained with DECT.

• Journal of the Korean Mathematical Society
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• v.41 no.2
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• pp.369-378
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• 2004

A canonical Finsler connection Nr is defined by a generalized Finsler structure called a (G, N)-structure, where G is a generalized Finsler metric and N is a nonlinear connection given in a differentiable manifold, respectively. If NT is linear, then the(G, N)-structure has a linearity in a sense and is called Berwaldian. In the present paper, we discuss what it means that NT is with a vanishing hv-torsion: ${P^{i}}\;_{jk}\;=\;0$ and introduce the notion of a stronger type for linearity of a (G, N)-structure. For important examples, we finally investigate the cases of a Finsler manifold and a Rizza manifold.

• Magazine of the Korean Society of Agricultural Engineers
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• v.36 no.3
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• pp.100-112
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• 1994

This tudy is to survey and analysis the water quality phase of Agricultural reservoirs through the case study of 18 reservoirs in Kyungpook Province in preparation for prevention disasters from the environmental hazards such as water pollutions. In these cases, the most hazardous pollution acts were Domestic animals excrements firstly, Human living wastge water secondly, Tourist resort sewage and Fertilize waste etc. in regular sequences. In the analysed results, pH, EC, BOD, DO, Cu, Ph, Cd were less than standard values recommended by the Environmental Authority and so they were estimated in scope of the safety value respectively. But few of factors being gradually closed with the hazardous point in the few places. At present, the hazardous environmental acts originated from the Domestic animals ex-crements, Human living waste water and Fertilize waste etc. in case the agricultural reservoirs, have to strongly be improved much better than before and prepared safety conditions for the rural living and agricultural life sciences.