• Journal of Applied Reliability
• /
• v.17 no.2
• /
• pp.112-121
• /
• 2017

Purpose: The most previous works on designing accelerated life tests (ALTs) are focused on the application of a single stress. Because of the difficulty to obtain the sufficient information in a reasonable duration using single stress only, there is needed in practice to use multiple-stress ALTs frequently. This paper presents new practical plans with two stresses for Weibull distribution. Methods: The four-level practical plans based on rectangle test region are proposed and compared with the corresponding three-level statistically optimal plans. Sensitivity analyses for assumed design parameters and life-stress relationship are conducted. Results: A procedure to choose practical ALT plans is illustrated with a numerical example and guidelines for planning two-stress ALTs are provided. Conclusion: The proposed two-stress ALT plans on practical constraints to assess a quantile of Weibull lifetime distribution at the use condition are efficient and robust.

• Journal of Convergence for Information Technology
• /
• v.9 no.11
• /
• pp.62-70
• /
• 2019

This study is a descriptive correlation study that analyzes the correlation between health-related lifestyle and quality of life characteristics of single household. Variables were selected 1,220 surveys of single household from the Korea Health Panel 2015. The average age of single-person households in Korea was 68.19, with women accounting for 71.3% of the single-person households. One household due to each private sector accounted for 64.8%, while 42.3% responded to their subjective health status as "ordinary." Smokers accounted for 31.7% and drinkers 34.7%, with 55.3%t of the low-activity group making up the largest amount of physical activity. The quality of life score was $13.31{\pm}1.828$. There was a positive correlation between smoking, drinking, physical activity and quality of life. Based on this data, progress of physical activity improvement program in support of the diversity and social relations are needed, and individual psychological and emotional support of single household needs to be developed.

• Industry Promotion Research
• /
• v.8 no.4
• /
• pp.113-122
• /
• 2023

This study is a research study aimed at finding out the relationship between lifestyle and life satisfaction of single youth households and the relationship between the mediating role of interpersonal relationships and the effect of parents' social and economic status regulation in the relationship between lifestyle and life satisfaction. To this end, this study conducted a self-written survey of single-person youth households across the country through an online survey institution, regardless of gender, and used a total of 501 copies out of 520 subjects for final results analysis. The data were analyzed using the SPSS 25.0 and AMOS 25.0 programs, and the applied statistical techniques included correlation analysis, confirmatory factor analysis, structural equation model analysis, multi-group analysis, and bootstrap. As a result of the study, there was a significant positive (+) correlation between lifestyle, life satisfaction, and interpersonal relationships of single youth households, and interpersonal relationships were found to have a mediating effect in the relationship between lifestyle and life satisfaction. It was found to have a significant positive (+) effect on income and income satisfaction, but the moderating effect of education, economic activity, housing ownership type, and class consciousness was not significant. Based on the results of these studies, it was intended to provide basic data for developing various community programs and institutional arrangements for single youth households.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.24 no.3 s.174
• /
• pp.701-709
• /
• 2000

As the welding spot forms a singular geometry of an external crack type, fatigue failure of spot-welded specimens can be evaluated by means of a fracture parameter. Recasting the load vs. fatigue life relationships experimentally obtained, we predicted the fatigue life of spot-weld specimens with a single parameter denoted the equivalent stress intensity factor. This crack driving parameter is demonstrated to successfully describe the effects of specimen geometry and loading type in a comprehensive manner. The suggested fatigue life formula for a single spot weld can play a key role in the design and assessment of spot-welded panel structures, in that the fatigue strength of multi-spots is eventually determined by the fatigue strength of each single spot. We therefore attempt to evaluate the effectiveness and validity of $K_e$ in predicting the fatigue life of auto seat belt anchor panel. We first establish finite element models reflecting the actual mechanical behavior of 3 types of seat belt anchor specimens. Using finite element models elaborately established, we then obtain the effective crack driving parameter $K_e$ composed of its ductility -dependent modal components. It is confirmed that the $K_e$ concept successfully predicts the fatigue life of multi-spot welded panel structures represented by auto seat belt anchors here.

• IMMUNE NETWORK
• /
• v.9 no.6
• /
• pp.243-247
• /
• 2009

In this study, we report the development of a new dual reporter vector system for the analysis of promoter activity. This system employs green fluorescence emitting protein, EGFP, as a reporter, and uses red fluorescence emitting protein, DsRed, as a transfection control in a single vector. The expression of those two proteins can be readily detected via flow cytometry in a single analysis, with no need for any further manipulation after transfection. As this system allows for the simultaneous detection of both the control and reporter proteins in the same cells, only transfected cells which express the control protein, DsRed, can be subjected to promoter activity analysis, via the gating out of all un-transfected cells. This results in a dramatic increase in the promoter activity detection sensitivity. This novel reporter vector system should prove to be a simple and efficient method for the analysis of promoter activity.

• Horticultural Science & Technology
• /
• v.33 no.5
• /
• pp.730-736
• /
• 2015

Tomato spotted wilt virus (TSWV) causes one of the most destructive viral diseases that threatens global tomato production. Sw-5b was reported as the resistance gene effective against TSWV. The objective of this research was to develop a single-nucleotide polymorphism (SNP) marker to distinguish tomato cultivars resistant to TSWV from susceptible cultivars for marker-assisted breeding. First, we determined genotypes for TSWV resistance in 32 commercial tomato cultivars using the previously reported Sw-5b gene-based marker. Then, DNA sequences of Sw-5b alleles in tomato cultivars showing resistant or susceptible genotypes were analyzed; a single SNP was found to distinguish tomato cultivars resistant to TSWV from susceptible cultivars. Based on the confirmed SNP, a SNP primer pair was designed. Using this new SNP sequence and high-resolution melting analysis, the same 32 tomato cultivars were screened. The results were perfectly correlated with those from screening with the Sw-5b gene-based marker. These results indicate that the SNP maker developed in this study will be useful for better tracking of resistance to TSWV in tomato breeding.

• Human Ecology Research
• /
• v.51 no.6
• /
• pp.603-612
• /
• 2013

With the increase of single-parent families in the Korean society, the perception of the function and structure of the family is changing. Thus, a public transition toward embracing single-parent families as another form of family is necessary. This study focuses on the families of divorced female single-parents using Walsh's family resilience framework with a strengths-based perspective. It aims to provide the basic data necessary for deducing policy-related and practical ways of supporting the families and for developing programs that help divorced female single-parent families maintain and reinforce resilience. Qualitative analysis was used as the research method. A preceding literature review was also carried out to collect data. The major findings of this study include the following: First, it was found that the average age of divorce is around 30-40, with children of school age. The mothers' level of education was relatively high, ranging from high school graduates to graduate school students. On Rothwell and Cohen's happiness scale, their objective level of happiness was higher (74.1) than that of the average Korean (64). Second, it was found they were very careful to avoid violence in everyday life as an after-effect of domestic violence, which was the major cause of their divorce. Third, their positive and optimistic attitudes about life even in adversity can be interpreted as Walsh's belief systems taking a more important role among other characteristics of family resilience.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.41 no.2
• /
• pp.326-340
• /
• 2017

This study explores the daily life of Korean designers in New York. We use in-depth interviews within the daily lives of participants to first reveal the time structure and meaning of everyday life. In this everyday time frame, this study reveals the content and meaning of life in New York, which is especially useful for fashion majors. Participants were 11 single Korean women around 30 years old working as designers in New York. Data was collected from Manhattan, New York, from November 2013 to February 2014 through the use of in-depth interviews and participant observation. Data collected daily life information on time usage, money, and energy that is first summarized into 229 meaning units. In the following, 55 central meanings were derived from stories common to behaviors for study participants and 19 subcategories were compressed into academic language. Finally, the generalized categories are divided into six categories of study life, work life, future life, family life, leisure life and fashion life. As a result of the first study, the daily time structure consisted of customary public time and personal repeat time. Second, the customary public time categories included the studying for 'Beginning to jump again to the best', 'Now working as a designer in New York', and future life expecting 'Future growing as a career woman'. Repeated personal time categories include family life: 'A single life of a lonely and poor gentile', leisure life: 'Healing life that is supported by abundant advanced culture', and fashion life: 'New York fashion life coexist with harmony'. Third, work was the center of everyday life for study participants versus fashion and leisure that were central to everyday life when not working.

• Journal of Korea Technical Association of The Pulp and Paper Industry
• /
• v.40 no.4
• /
• pp.10-15
• /
• 2008

Flocculation phenomena of the stock mixed with cellulosic fibers, fillers and polymers were investigated by a new turbidity measurement system consisted of a probe-type turbidimeter, data acquisition system and computer. The probe-type turbidimeter allowed to measure the real time flocculation of the stock induced by single polymer and microparticle systems. Flocculation phenomena were evaluated by average and final relative turbidity indices. Turbidity and flocculation showed inverse relationship, i.e. the turbidity decreased with the formation of flocs. Relative turbidity of the stock treated with microparticle system was lower than that of the stock containing single polymer system, which indicated that the microparticle system showed greater floc forming efficiency than single polymer system.

• Korean Journal of Family Social Work
• /
• no.59
• /
• pp.5-26
• /
• 2018

This study aims to examine the mediating effect of parental monitoring and child's self-esteem on the relationship between parental time and child's life satisfaction in single mother families. For this purpose, MOGEF (Ministry of Gender Equality and Family)'s 'Research data of adolescents in 2015' was used and 117 single mothers and their children aged 9 to 18 were selected for the analysis. Structural Equation model analysis reveals that adolescent's self-esteem has a mediating effect on the relationship between parental time and adolescent's life satisfaction, though parental time and parental monitoring have no significant effect on adolescent's life satisfaction. With these results, policy suggestions to support single mothers' parental time were proposed.