• Journal of the Korean Geographical Society
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• v.44 no.3
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• pp.339-354
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• 2009

The purposes of this study are to identify many implications of commuting regional type according to the features of foreigner commuting. Research on the pattern of distribution of foreigners has been very simple and limited because foreigners usually lived together in a specific area, and their workplace often tended to be their residence. However they currently live dispersed more Widely, and their job and housing increasingly tend to be mismatched. This study divided areas inhabited by foreigners into general one characterized by job-housing match and exceptional one characterized by job-housing mismatch, and then examined the features of foreigner commuting. General commute type showed a high rate of intra area commute and foreign workers' universal features. Inflow commute type showing high E/R ratio. In these areas, outflow commuters had a short journey to work while inflow commuters had relatively a long journey to work, and professionals accounted for a high proportion of employees. Outflow commute type showing low E/R ratio. In these areas, outflow commuters had a long journey to work while inflow commuters had a relatively short journey to work. The composition ratio of three commute types was different according to nationality and visa type.

• Journal of Environmental Health Sciences
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• v.50 no.2
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• pp.157-167
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• 2024

Background: Several previous studies have shown that commuting is a source of stress for undergraduate students. However, few studies have investigated the effect of commuting on academic stress among undergraduate students, and there has been little awareness of the environmental impact of commuting. Objectives: To evaluate the associations between commute type and/or time and academic stress among undergraduate students in South Korea, focusing on environmental sustainability. Methods: We conducted an online survey and obtained information on commute types, commute times, and academic stress from 510 undergraduate students aged ≥19 years. Academic stress was comprised of five sub-categories of stress, and total academic stress ranged from 5 to 25 points. Multiple linear regression analysis was used to analyze the associations between commute type and commute time and academic stress. Furthermore, the students were grouped into 21 categories based on their transportation mode for commuting. CO₂ emission factors per each commuting category were calculated using the transportation type's CO₂ emission data from previous studies. Spearman's correlation analysis was used to confirm the correlation between CO₂ emission factors and total academic stress. Results: Students using home-to-school transportation without transfers (vs. walking) showed a significantly higher total academic stress of 2.19 points (95% CI: 0.58, 3.80). In contrast, students using school-to-home transportation without transfers (vs. walking) showed a significantly lower total academic stress of 1.96 points (95% CI: -3.55, -0.38). Moreover, students using transportation with lower CO₂ emission factors had lower academic stress scores (home-to-school: correlation coefficient = 0.507, p<0.001; school-to-home: correlation coefficient = 0.491, p<0.001). Conclusions: Our findings suggest that both commute type and time are significantly associated with academic stress among South Korean undergraduate students. When students select environmentally-friendly transportation, they may not only improve their mental health but also improve climate resilience.

• Journal of Korean Society for Atmospheric Environment
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• v.17 no.4
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• pp.321-329
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• 2001

This study included three experiments to evaluate in-vehicle exposures to PM10 and CO: 1) evaluation of in-passenger car exposures, 2) evaluation of in-public bus exposures, and 3) simultaneous evaluation of in-passenger car and in -university bus exposures. The tests of four factors (transportation mode, passenger-car type, commute period, and commute season were focused. A total of 40 actual passenger car commuters, 20 public bus commuters, and four university buses were recruited or surveyed. The same commuters ware participated in both the summer and winter studied. Two factory such as transportation mode and passenger-car type were found to have little effect on the in-vehicle levels of PM10 and CO. Commute period was found to have little effect on the in-vehicle CO levels. Conversely, the other factor, commuting season was found to influence on the in-vehicle levels of PM10 and CO. The present study also confirmed that under the Korean commute conditions, vehicle interiors are an important microenvironment for exposure to PM10 and CO. This was supported by finding that the in-vehicle Air levels were much higher than ambient air levels reported by several previous studies. The mean in -vehicle PM10 concentrations were 114 and 103$\mu\textrm{g}$/m$^3$for passenger cars and public buses, respectively. For CO, the mean in-vehicle concentrations were 2.9 and 2.6 ppm for passenger cars and public louses, respectively.

• Bulletin of the Korean Mathematical Society
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• v.44 no.1
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• pp.195-202
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• 2007

We prove that a real hypersurface M in a complex space form Mn(c), $c{\neq}0$, whose Ricci operator and structure tensor commute each other on the holomorphic distribution and the Ricci operator is ${\eta}-parallel$, is a Hopf hypersurface. We also give a characterization of this hypersurface.

• Bulletin of the Korean Mathematical Society
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• v.43 no.2
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• pp.235-244
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• 2006

We shall give a characterization of a real hypersurface M in a complex space form Mn(c), $c\;{\neq}\;0$, whose Ricci operator and structure tensor commute each other on the holomorphic distribution of M, and the Ricci operator is ${\eta}-parallel$.

• Kyungpook Mathematical Journal
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• v.50 no.2
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• pp.213-228
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• 2010

A weighted version of the geometric mean of k ($\geq\;3$) positive invertible operators is given. For operators $A_1,{\ldots},A_k$ and for nonnegative numbers ${\alpha}_1,\ldots,{\alpha}_k$ such that $\sum_\limits_{i=1}^k\;\alpha_i=1$, we define weighted geometric means of two types, the first type by a direct construction through symmetrization procedure, and the second type by an indirect construction through the non-weighted (or uniformly weighted) geometric mean. Both of them reduce to $A_1^{\alpha_1}{\cdots}A_k^{{\alpha}_k}$ if $A_1,{\ldots},A_k$ commute with each other. The first type does not have the property of permutation invariance, but satisfies a weaker one with respect to permutation invariance. The second type has the property of permutation invariance. We also show a reverse inequality for the arithmetic-geometric mean inequality of the weighted version.

• Korean Journal of Health Education and Promotion
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• v.28 no.2
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• pp.27-40
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• 2011

Objectives: This study was conducted to identify health-promoting behaviors and related factors by type of residence between two groups of college students: those who live in dormitories and those who commute from home. Methods: We used the data from 2,287 students (870 male, 1417 female) from 14 colleges in Daegu and Kyungpook areas and compared health-promoting practice scores, general characteristics, health environment, and parental support. Multiple regression analysis was performed with health-promoting practice scores as a dependent variable. Results: Dormitory residents presented significantly lower health-promoting practice scores than commuters in both gender. Multiple regression analysis showed that the factors associated with health-promoting behaviors were health environment (p<0.05) and parental influence/support (p<0.01) for male dormitory residents. For female dormitory residents interest in health(p<0.05), stress(p<0.05), and parental influence/support(p<0.01) were associated. Conclusions: Systematic development of health education programs would be needed for the practice of health promotion behavior of college dormitory students with the help of environmental and institutional support. We suggest a program for stress management, smoking, health behavior, and alcohol and a parental program to increase contact with their children for a positive parental influence and support.

• Kyungpook Mathematical Journal
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• v.56 no.4
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• pp.1207-1235
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• 2016

Let M be a real hypersurface with constant mean curvature in a complex space form $M_n(c),c{\neq}0$. In this paper, we prove that if the structure Jacobi operator $R_{\xi}= R({\cdot},{\xi}){\xi}$ with respect to the structure vector field ${\xi}$ is ${\phi}{\nabla}_{\xi}{\xi}$-parallel and $R_{\xi}$ commute with the structure tensor field ${\phi}$, then M is a homogeneous real hypersurface of Type A.

• Kyungpook Mathematical Journal
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• v.56 no.2
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• pp.541-575
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• 2016

Let M be a real hypersurface of a complex space form with almost contact metric structure (${\phi}$, ${\xi}$, ${\eta}$, g). In this paper, we prove that if the structure Jacobi operator $R_{\xi}= R({\cdot},{\xi}){\xi}$ is ${\phi}{\nabla}_{\xi}{\xi}$-parallel and $R_{\xi}$ commute with the structure tensor ${\phi}$, then M is a homogeneous real hypersurface of Type A provided that $TrR_{\xi}$ is constant.

• Journal of Families and Better Life
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• v.20 no.6
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• pp.49-60
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• 2002

This study focused on family stresses and coping strategies among commuting couples. The participants of this study consisted of a national samples of 134 couples(268 individuals), who had been commuting for at least six months. The major findings obtained from the study are summarized in the following: First, the degree of family stresses among commuting couples was 2.98, when the maximal stress value was set to 5.0. No difference in the level of stress was detected from the roles of the wife and those of the husband. The most stressful aspect for the commuting couples came from the role of parents who care for their children. The second stressful aspect was their responsibility for their own parents, and finally the stress from the housework and maintenance of their marital lives followed next. There was no difference between the wives and husbands on the stressors. Secondly, the level of the coping strategies developed by the commuting couples themselves against their stresses was 3.37, when the maximal stress coping value was set to 5.0. Again, there was no difference in this level between wives and husbands. Among the strategies, they used ‘cognitive restructuring’the most frequently; sharing their responsibilities with other members in family life came next; and developing their own techniques to manage their stresses followed. Thirdly, the ages of the couple, the age of the first child, type of jobs, duration of the marriage and commute, and frequency of meeting affected the level of family stress among commuting couples. Finally, commuting couples developed quite different strategies to cope with their family stresses, and religion and family type affected significantly the type of coping strategies.