• Journal of Korean Society of Rural Planning
• /
• v.15 no.4
• /
• pp.89-107
• /
• 2009

The main objective of the present study is to find out which factors affect coresidence between older Korean parents and their adult children and to examine the regional patterns of the phenomenon. The 1980, 1995 and 2005 Korea census data are used to investigate the determinants of two types of parent-child coresidence. The two types are coresidence with married adult children and one with unmarried adult children. The study takes advantage of the multilevel mltinomial logit model, allowing the model to capture regional differences. Findings from the study are: (1) Korean parents' coresidence with their married adult children and one with their unmarried adult children are distinctive in their determinants; (2) variables related to wealth or economic status are positively related with possibilities of both types of coresidence; and (3) considerable regional differences in the possibility of coresidence do exist among regions in Korea.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
• /
• v.7 no.7
• /
• pp.599-608
• /
• 2017

This study investigated factors that are associated with companion animal ownership among urban elderly persons. This study was based on data from 2014 Seoul Survey, and a total of 4,717 people aged 60 years or older were selected for the analyses. Community level data were from 2014 Seoul statistics and they included park area per person, number of elderly recreational facilities, and number of public sports facilities based on 25 districts of Seoul Metropolitan City. This study examined differences between companion animal owners and non-owners concerning individual level factors and community level factors. Factors that are associated with companion animal ownership were examined using multilevel logistic regression analysis. Among individual level variables, companion animal ownership was associated with gender, marital status, income, number of household members, and housing type. Among community level variables, park area per person was a significant factor that is associated with companion animal ownership. Study findings can be used Based on study findings, implications of the study and directions for future research are discussed.

• Proceedings of the KOR-KST Conference
• /
• 2007.11a
• /
• pp.210-218
• /
• 2007

Road freight transport industry in Korea contains many and complicate problems such as over supply of the vehicle caused by rapid policy changes, illegal multilevel transactions, poor truck drivers working environment, lack of road freight transport related statistics and so on. Korean government has developed various logistics industrial policy trying to solve these problems in various ways. However, the relationship among the problems and action plans has been more and more entangled since the part of suggested policies have made another perverted problems. These complex structure of the toad freight transport industry in Korea makes difficult to identify and to solve the problems. Causal map method helps to give a clean picture to understand the complex industry at a glance. This study contributes for visualization of the causal relationships among the existing problems and related policy issues in the road freight transport industry in Korea by causal map. This study could be helpful to develop the actual road freight transport industrial policies including the illogical multilevel and unfair transaction in Korea.

• Journal of Korean Academy of Nursing
• /
• v.45 no.5
• /
• pp.694-703
• /
• 2015

Purpose: This study was a prospective longitudinal study to identify changes in quality of life in patients undergoing allogeneic hematopoietic stem cell transplantation (HSCT). It was based on Roy's adaptation model. Methods: The questionnaires were administered before HSCT, 30 and 100 days after HSCT. Of the 48 potentially eligible patients, 44 (91.7%) participated in the study and 40 (90.9%) completed the questionnaires at 100 days after HSCT. Multilevel analysis was applied to analyze changes in quality of life. Results: Overall, quality of life showed a decreasing tendency from pre-HSCT to 100 days after HSCT. The adaptation level of participants was compensatory. Type of conditioning was the significant factor influencing quality of life before HSCT (${\beta}_{00}$=79.92, p <.001; ${\beta}_{01}$= - 12.64, p <.001) and the change rate of quality of life (${\beta}_{10}$= - 1.66, p =.020; ${\beta}_{11}$=2.88, p =.014). Symptom severity (${\beta}_{20}$= - 1.81, p =.004), depression (${\beta}_{30}$= - 0.58, p =.001), social dependency (${\beta}_{40}$= - 0.35, p =.165), and loneliness (${\beta}_{50}$= - 0.23, p =.065) had a negative effect on changes in quality of life. Symptom severity and depression were statistically significant factors influencing changes in quality of life. Conclusion: According to the results of this study, the development of nursing intervention is needed to improve quality of life in patients undergoing allogeneic hematopoietic stem cell transplantation in the early immune reconstruction period. The interventions should include programs to enhance coping capacity and programs to help control symptom severity and depression. Also these interventions need to be started from the beginning of HSCT and a multidisciplinary approach would be helpful.

• Journal of the Korean Regional Science Association
• /
• v.36 no.3
• /
• pp.3-16
• /
• 2020

The causes and effects of intra-urban spatial inequality have received much scholarly attention. However, the effects of urban spatial inequality on resident perceptions and the mechanisms through which it is sustained and reproduced remain mostly unknown. This study aimed to investigate whether regional deprivation, the relative socioeconomic standing of a region, affects the residents' perceptions of upward social mobility. By employing the ordinal logistic multilevel model to analyze nested data collected from Seoul, South Korea, this study found that the regional deprivation has a significant negative effect on residents' perception of upward social mobility. The results of this study suggest that one way in which spatial inequality is sustained and reproduced is by the effects of regional deprivation, having negative impacts on the aspirations and socioeconomic activities of residents. This study is expected to provide meaningful implications for planning and policy aimed to combat spatial inequality.

• Journal of agricultural medicine and community health
• /
• v.47 no.4
• /
• pp.268-274
• /
• 2022

Objectives: The purpose of this study was to identify the individual and regional risk factors on depression using community-based data in Jeollabuk-do. Methods: This cross-sectional study obtained data from the Community Health Survey 2018 in Jeollabuk-do. The dependent variable was depression measured by Patient Health Questionnaire-9 (PHQ-9). The prevalence of depression was defined if total score of PHQ-9 was 10 or higher. A multilevel analysis was conducted to consider individual and regional level independent variables that could be risk factors for depression. Results: In the individual level, female gender and smokers had significantly higher odds ratios (ORs) for depression of 1.58 and 1.72, respectively. Subjects with economic activity, higher income and higher education had significantly lower ORs of 0.53, 0.41 and 0.66. In the regional level, higher greening rates and lower levels of PM2.5 had statistically lower ORs at the significance level of 10%. Conclusion: By conducting this study, risk factors associated with depression were identified in individual- and regional-level. This study suggests that health projects are needed to control regional level risk factors including community networks for mental health management in addition to the traditional individual level risk factors.

• Journal of Electrical Engineering and Technology
• /
• v.10 no.4
• /
• pp.1552-1557
• /
• 2015

The paper unleashes a new idea to arrive at reduced switch count topological structures configured in the form of a matrix for a cascaded Multi level inverter (CMLI). The theory encircles to minimize the number of switches involved in the conduction path and there from acclaim reduced input current distortion, lower switching losses and electromagnetic interference. The focus extends to standardize the number of power devices required for reaching different levels of output voltage from the same architecture. It includes appropriate pulse width modulation (PWM) strategy to generate firing pulses and ensure the desired operation of the power modules. The investigative study carries with it MATLAB based simulation and experimental results obtained using suitable prototypes to illustrate the viability of the proposed concept. The promising nature of the performance projects a new dimension in the use of single phase MLIs for renewable energy related applications.

• Proceedings of the KIPE Conference
• /
• 2010.07a
• /
• pp.232-233
• /
• 2010

This paper investigates occupational exposure to time-varying magnetic field generation in high power rectifier systems. Two different kinds of high power rectifier systems of 25kA are modeled and analyzed. The performance is compared and evaluated on the basis of exposure guidelines from ICNIRP. In order to focus on the qualitative effect of rectifier operation, the mechanical structure of current carrying conductors is simplified as infinite long bus-bar model and low frequency harmonic contents up to 65kHz are considered. Thyristor rectifier generates a significant amount of low frequency magnetic field harmonic contents both at ac and dc side of rectifier infringing the limit from ICNIRP. The multilevel rectifier-IGCT type has almost negligible field generation from ac input side and smaller harmonic contents in dc load side complying with ICNIRP guideline. This remarkable advantage of multilevel rectifier-IGCT type can lead to very simple site layout design for installation and cost-effective compliance to guideline of occupational exposure against magnetic field.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
• /
• 1999.11a
• /
• pp.323-330
• /
• 1999

The conventional analysis for the numerical computation of fluid film thickness with elastic deformation of contact region. is performed by Newton-Rephson method for its 18st convergence characteristics. However, both high load and relatively low sliding velocity frequently make it impossible for Newton-Rahpson method to get both converged and stable solutions. In particular, this method cannot provide converged Solution under the condition of high load above 1.0 GPa which frequently occurs in line contact of EHL problem. Multigird multi-level method for the solver of non-linear partial differential equation including solid deformation is preferred to Newton-Rshpson method for better convergence and stability and is applied to line contact EHL behavior in this study.

• The Transactions of the Korean Institute of Electrical Engineers B
• /
• v.55 no.8
• /
• pp.430-435
• /
• 2006

This paper presents a method about the efficiency analysis and the harmonic reduction of single phase NPC multi-level inverter with LC-trap filter and LCR output filter. The proposed LC-trap filter is comprised of a conventional LC output filter, by using LC-trap filter the need for high damping resistor and low LC cut-off frequency is eliminated. Also, low damping resistor is increased the efficiency of the output filter. Experimental verification of the proposed circuit is provided with single phase NPC multilevel inverter system and DSP controller.