• Korean Journal of Mathematics
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• v.12 no.1
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• pp.91-106
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• 2004

We prove the regularity of a moving interface of the solutions of the initial value problem of equation (1.1) is $C^{\infty}$.

• East Asian mathematical journal
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• v.35 no.1
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• pp.51-58
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• 2019

For a nondegenerate irreducible projective variety, it is a classical problem to describe its defining equations. In this paper we precisely determine the defining equations of some rational curves of maximal regularity in ${\mathbb{P}}^4$ according to their rational parameterizations.

• East Asian mathematical journal
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• v.38 no.1
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• pp.129-141
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• 2022

We obtain interior regularity estimates in the weighted Orlicz spaces for viscosity solutions of fully nonlinear uniformly parabolic equations u_t - F(D² u, x, t) = f(x, t) in Q₁ under relaxed structure conditions on the nonlinear operator F.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2003.03a
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• pp.85-92
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• 2003

Hysteretic behaviors of a seismic isolator are identified by using the regularized output error estimator (OEE) based on the secant stiffness model. A proper regularity condition of tangent stiffness for the current OEE is proposed considering the regularity condition of Duhem hysteretic operator. The proposed regularity condition is defined by 12-norm of the tangent stiffness with respect to time. The secant stiffness model for the OEE is obtained by approximating the tangent stiffness under the proposed regularity condition by the secant stiffness at each time step. A least square method is employed to minimize the difference between the calculated response and measured response for the OEE. The regularity condition of the secant stiffness is utilized to alleviate ill-posedness of the OEE and to yield numerically stable solutions through the regularization technique. An optimal regularization factor determined by geometric mean scheme (GMS) is used to yield appropriate regularization effects on the OEE.

• The Korean Journal of Community Living Science
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• v.19 no.2
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• pp.191-199
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• 2008

The purpose of this study was to obtain an understanding of the effect of regular exercise on obesity indices, the psychosocial wellbeing index, dietary factors and exercise regularity among 146 healthy mothers and 146 their daughters. "Mother" subjects were divided into two groups classified as regular exercise group(REG) and none exercise group(NEG). The exercise regularity of REG's daughters(30.8%) and of NEG's daughters (2.0%) was significantly different(p<0.001). The Obesity Indices(Body Mass Index (BMI), Waist Hip Ratio(WHR) and Percentage of Ideal Body Weight(PIBW)) of NEG's daughters were significantly higher than those of REG's daughters(p<0.001). But the psychosocial wellbeing index was not significantly different between REG's daughters and NEG's daughters. Intake of total energy, protein, fat, Ca, niacin and Fe were significantly different(p<0.001) between REG's daughters and NEG's daughters. Especially, vitamin C intake of REG's daughters was significantly higher than that of NEG's daughters(p<0.001). The exercise regularity of mothers was mainly related with Obesity Indices and nutrient intake in their daughters. Therefore, it might be necessary to maintain exercise regularity to prevent obesity and diet related problems in mothers and their daughters.

• Nutrition Research and Practice
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• v.2 no.4
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• pp.269-274
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• 2008

Consuming regular meals has been studied in relation to better health, while higher regularity of eating-out has been linked to obesity. This study examined whether acculturation was associated with regularity of meals, eating-out, and overweight in Korean Americans. Pre-tested questionnaires were mailed to a U.S. national sample with Korean American surnames, and 55% of the deliverable sample responded, producing 356 usable questionnaires. Acculturation was measured using a two-culture matrix model and Gordon's theoretical work, and showed there were three distinct groups (acculturated, bicultural, and traditional). Only 36% reported that they regularly ate three meals a day. Breakfast was the least frequent meal of the day with 43% reporting eating breakfast everyday. More than half (58%) reported that they usually eat out or get take-out food at least once a week. After controlling for age, sex, income, education, and working status, higher acculturation was related to greater regularity of eating-out, but not meal regularity. A total of 28% of men and 6% of women were overweight (BMI>25), and there were significant and positive relationships between body weight status and acculturation in men but not women. However, no significant relationships between frequency of meals and eating-out and overweight status were present. This study did not find significant relationships of meal regularity and eating-out with body weight, however, given the positive relationship between acculturation and eating-out among the subjects and the well-established relationship between eating-out and obesity, nutrition education about skipping meals and eating-for Korean Americans may be useful to prevent such relationships from developing.

• Korean Journal of Childcare and Education
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• v.18 no.2
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• pp.105-124
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• 2022

Objective: This study investigated the double mediating effects of maternal and paternal parenting stress and the regularity of children's daily routines in the association between maternal and paternal parenting time and children's self-regulation. Methods: A total of 235 preschool children aged 4-5 years and their mothers and fathers participated in the study. Parenting time, parenting stress, and children's self-regulation were assessed using both mothers' and fathers' reports, but the regularity of daily routines was assessed using mothers' reports only. The data was analyzed using SEM in Mplus 8.2. Results: Mothers' and fathers' parenting stress appeared to have cross-spousal mediated effects of their parenting time on children's self-regulation. Higher levels of mothers' and fathers' parenting time predicted higher levels of children's self-regulation through only a lower level of mothers' parenting stress and a higher level of the regularity of daily routines. Conclusion/Implications: Findings indicated that parents' parenting time played a significant protective factor in reducing parenting stress and increasing the regularity of daily routines among family members. This cross-spousal influence on parenting process can inform the development of prevention programs and parenting education to promote self-regulation skills among preschool children.

• Nutrition Research and Practice
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• v.16 no.2
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• pp.205-216
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• 2022

BACKGROUND/OBJECTIVES: While many obesity studies have pointed out the importance of meal regularity, few have conducted empirical analyses using data from food diaries. We examined the association between meal regularity (i.e., meal time regularity [MTR] and calorie intake regularity [CIR]) and weight loss. SUBJECTS/METHODS: We collected food diary data from 637 women who had participated in commercial weight loss programs for 28-168 days (4-24 weeks). This study defined "meal regularity" in terms of two concepts: MTR and CIR. MTR refers to how regularly people eat their meals (i.e., at certain times each day), whereas CIR refers to how regularly people consume a certain amount of calories at each meal. We conducted multiple regression analyses. RESULTS: MTR (model 1: β = -2,576.526, P < 0.001; model 2: β = -1511.447, P < 0.05; model 3: β = -1,721.428, P < 0.05) and CIR (model 1: β = -1,231.551, P < 0.01; model 2: β = -2,082.353, P < 0.001; model 3: β = -1,343.490, P < 0.01) turned out to be significant determinants of the amount of weight loss in breakfast, lunch, and dinner contexts. While meal regularity (i.e., MTR and CIR) was significantly associated with weight loss, daily calorie intake from meals was not significantly associated with the amount of weight loss (model 1: β = 0.13, P > 0.05; model 2: β = 0.11, P > 0.05; model 3: β = 0.14, P > 0.05). Subjects who consumed an equal amount of calories per meal throughout the day lost more weight than those who did not (model 4: β = -3,675.51, P < 0.001). CONCLUSIONS: Eating each meal (i.e., breakfast, lunch, and dinner) at a certain time every day may increase weight loss success. Also, consuming the same amount of calories at each meal may help weight loss success.

• Bulletin of the Korean Mathematical Society
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• v.33 no.1
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• pp.17-28
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• 1996

• Proceedings of the Korean Society for Cognitive Science Conference
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• 2002.05a
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• pp.111-116
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• 2002

The regularity effect for printed word recognition and naming depends on ambiguities between single letters (small grain-size) and their phonemic values. As a given word is repeated and becomes more familiar, letter-aggregate size (grain-size) is predicted to increase, thereby decreasing the ambiguity between spelling pattern and phonological representation and, therefore, decreasing the regularity effect. Lexical decision and naming tasks studied the effect of repetition on the regularity effect for words. The familiarity of a word from was manipulated by presenting low and high frequency words as well as by presenting half the stimuli in mixed upper- and lowercase letters (an unfamiliar form) and half in uniform case. In lexical decision, the regularity effect was initially strong for low frequency words but became null after two presentations; in naming it was also initially strong but was merely reduced (although still substantial) after three repetitions. Mixed case words were recognized and named more slowly and tended to show stronger regularity effects. The results were consistent with the primary hypothesis that familiar word forms are read faster because they are processed at a larger grain-size, which requires fewer operations to achieve lexical selection. Results are discussed in terms of a neurobiological model of word recognition based on brain imaging studies.