• Industrial Engineering and Management Systems
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• v.7 no.2
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• pp.160-170
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• 2008

This paper proposes a mathematical model for converting conveyor assembly line to cellular manufacturing in complex production environments. Complex production environments refer to the situations with multi-products, variant demand, different batch sizes and the worker abilities varying with work stations and products respectively. The model proposed in this paper aims to determine (1) how many cells should be formatted; (2) how many workers should be assigned in each cell; (3) and how many workers should be rested in shortened conveyor line when a conveyor assembly line should be converted, in order to optimize system performances which are defined as the total throughput time and total labor power. We refer the model to a new production system. Such model can be used as an evaluation tool in the cases of (i) when a company wants to change its production system (usually a belt conveyor line) to a new one (including cell manufacturing); (ii) when a company wants to evaluate the performance of its converted system. Simulation experiments based on the data collected from the previous documents are used to estimate the marginal impact that each factor change has had on the estimated performance improvement resulting from the conversion.

• Journal of Forest and Environmental Science
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• v.34 no.3
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• pp.253-257
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• 2018

Climate models forecast more frequent and a longer period of drought events which may impact forest soil carbon dynamics, thereby altering the soil respiration (SR) rate. We examine the simulated drought effects on soil $CO_2$ effluxes from soil surface partitioning heterotrophic and autotrophic soil respiration sources. Three replicates of drought plots ($6{\times}6m$) were constructed with the same size of three control plots. We examined the relation between $CO_2$ and soil temperature and soil moisture, each being measured at a soil depth of 15 cm. We also compared which factor affected $CO_2$ efflux more under drought conditions. Total SR, autotrophic respiration (AR) and heterotrophic respiration (HR) were positively correlated with soil temperature (p < 0.05), and the relationships were stronger in roof plots than in control plots. Total SR, AR, and HR were negatively correlated only in roof plots, and the only HR showed a significant correlation (p < 0.05, r = -0.59). Soil respiration rates were more influenced by soil temperature than by soil moisture, and this relationship was more evident under drought conditions.

• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.3
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• pp.354-365
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• 2019

Megabenthos samples were collected using 10-min trawls towed at 17 stations from 2015 to 2016. The dominant species (>1% of the total density) were Stegophiura sterea (10.4%) and two subtropical species, Mactrinula dolabrata (9.0%) and Acila divaricate (8.3%), respectively. The community structure of the megabenthos fell into four groups: the southeast, the southernmost region off Jeju Island, the frontal zone of the South Sea with C3, and a diagonal area from the south coast to the western side of Jeju Island. The total numbers of species, diversity, density and biomass were higher in the C3 region of the South Sea. Environmental factor analysis showed that differences in the megabenthos community were related to depth, gravel contents, and sorting value (${\sigma}$). These results indicate that changes in the marine environmental conditions in the South Sea of Korea affect the megabenthos species' composition and diversity.

• Research in Community and Public Health Nursing
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• v.30 no.2
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• pp.109-118
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• 2019

Purpose: The purpose of this study is to identify factors affecting the quality of life among community-dwelling older women with urinary incontinence (UI). Methods: A cross-sectional study was conducted with 475 women aged 60 or over who were recruited from 10 primary health care facilities in rural Korea. Data were collected using a structured questionnaire consisting of socio-demographic, health-related, and UI-related characteristics. The quality of life was assessed using Incontinence Quality of Life (I-QOL). SPSS/WIN 23.0 program was used to analyze descriptive statistics, $x^2$ test, t-test, ANOVA, Pearson's Correlation, and hierarchical regression. Results: Of 475 subjects, 180 (37.9%) had urinary incontinence. The mean scores of I-QOL of women with and without UI were 76.87 and 94.77, respectively. The results of hierarchical regression analysis show that the Questionnaire for Urinary Incontinence Diagnosis total score was the greatest influencing factor, followed by age and the International Consultation on Incontinence Questionnaire-Short Form total score. Conclusion: The study revealed that factors related to UI symptoms are more likely to have impact on the quality of life in women with UI. It suggests that early detection or management of UI is important in improving the quality of life of women with UI.

• Korean Journal of Agricultural Science
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• v.47 no.4
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• pp.727-742
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• 2020

Point cloud-based 3D maps can obtain many kinds of information for maintenance work on forest road networks. This study was conducted to compare the importance of each factor to select the factors required for the mapping of 3D forest road maps. This can be used as basic data for attribute information required to maintain forest road networks. The results of this study found that out of a total of 30 indexes extracted for mapping 3D forest roads, a total of 21 indexes related to stakeholder groups were significantly different. The importance of the index required by the civil service group was significantly higher than that of the other groups overall. In the case of the academic group, the index importance for cut slope, fill slope, and drainage facility was significantly higher. On the other hand, the index importance for the forestry cooperative and forest professional engineer group was mostly distributed between the civil servants' group and the academic group. In particular, the type of drainage system showed the highest value among the detailed indexes. Overall, drainage related factors in this survey had high coefficient values. The impact of water on forest roads was the most important part in road maintenance. In addition, the soil texture had a high value in relation to slope stability. This is thought to be because the texture of the soil affects the stability of the slope.

• The Journal of Industrial Distribution & Business
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• v.9 no.12
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• pp.31-43
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• 2018

Purpose - Smartphone shopping malls provide customers with a variety of tangible and intangible services including web sites, web design, use convenience, information for products and shopping and various after services. Accordingly, it is needed to expand and classify service qualities based on the various services provided by smartphone shopping malls, and then analyze path structures of smartphone shopping malls' qualities → customer satisfaction → behavioral intention. The purpose of this study is to categorize the qualities of smartphone shopping mall users based on the e-SERVQUAL by Lee(2002) and the SERVQUAL by Parasuraman et al.(1988, 2005), the smartphone shopping malls' service qualities based on service quality of smartphone shopping malls used in the previous use studies, and the Website quality factors of service industry and to analyze path structure of smartphone shopping mall's qualities → customer satisfaction → behavioral intention on college students in order to confirm the system of smartphone shopping malls' qualities. Research design, data, and methodology - This study's survey was carried out on the college students of university located in northeastern of Seoul. It was from December 7 - 15, 2017, and a total of 240 questionnaires were distributed, with 228 collected. Of them, effective questionnaires used in the final study were a total of 201 except 27 that couldn't be used. In this study, empirical analysis was done with factor analysis, correlation analysis, multiple regression analysis, simple multiple regression analysis and moderating regression analysis by using Statistics Package SPSS18.0. Results - The study results are as follows: First, smartphone shopping malls' qualities were classified into six categories like customer system quality, Web design quality, convenience quality, information-offering quality, service quality, and product quality. Second, it showed that system quality, Web design quality, and information-offering quality had a positive impact on customer satisfaction, respectively. Third, it suggested that quality factors of smartphone shopping mall users had a positive impact on customer satisfaction in the order of quality, information-offering quality, system quality and Web design quality. Finally, it showed that customer service quality, product quality, and convenience quality did not have a positive impact on customer satisfaction. In addition, it said that customer satisfaction of smartphone shopping mall users had a positive impact on behavioral intention and thereby, the higher the customer satisfaction was, the higher the relations between reuse intention and recommendation intention were. Meanwhile, moderating regression analysis showed that trust did not have moderating effect in the relations between customer satisfaction and behavioral intention. The above study revealed that smartphone shopping malls' qualities were classified into six categories and it was possible to generalize after empirical analysis was made in the path structure. Conclusions - Smartphone shopping mall users consider usefulness of obtaining shopping information and quality on quick and abundant shopping information more important than access environment of smartphone shopping malls and kind services of smartphone shopping mall managers. Thereby, smartphone shopping mall marketers need to take service qualities like system quality and information-offering quality into more consideration.

• Journal of Korean Clinical Nursing Research
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• v.25 no.3
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• pp.221-236
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• 2019

Purpose: The purpose of this study was to systematically review and identify factors relevant to the positive psychological capital of clinical nurses. Methods: These was no limit on year of publication. Articles related to Korean clinical nurses were retrieved from computerized database using a manual search. A systematic review was conducted based on the PRISMA flow. The total correlational effect size (ESr) for each related factor was calculated from Fisher's Zr. Funnel plots, fail-safe numbers, and Egger regression tests were used to evaluate publication bias in meta-analysis studies. The correlational effect size of 25 studies was analyzed through meta-analysis using Comprehensive Meta-Analysis software 3.0 (CMA). Results: The review included 25 studies. In the systematic review, 14 demographic factors and 46 organizational factors were found to be influential. Eleven factors (6 demographic factors and 5 organizational factors) were appropriate for meta-analysis. The overall effect size was .26. The demographic total correlation effect size of related factors was .20 and the total effect size of organization was .46. Organizational commitment (ESr=.38) and job satisfaction (ESr=.54) were statistically positively related variables. Negative variables were burnout (ESr=-.61), turnover intention (ESr=-.41) and workplace bullying (ESr=-.33). The total effect size of the organizational factors was larger than the demographic total effect size. There was no publication bias except for demographic variables. Conclusion: Organizational factors and adjustable variables have a significant impact on positive psychological capital. The results of this study support the need for development of interventions focusing on organizational factors.

• Journal of Korean society of Dental Hygiene
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• v.12 no.5
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• pp.973-985
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• 2012

Objectives : The aim of this study is to investigate the possible impact factors on adults' self-reports of dry mouth and to develop strategies to improve oral health education policy. Methods : This study was conducted on a total of 622 self-administered questionnaires adult above 20 and under 65 years of age living in Seoul and Gyeonggi provinces. The final participants consisted of 443 adults without chronic illness, taking medications and wearing dentures. The Hierarchical Multiple Regression model with three stages was used to assess the association for exposure of interest, such as socio-demographics, health-related behavior, mental health and self-reported of dry mouth. Results : The participants reported mean score of dry mouth($6.32{\pm}4.47$), of which 191 were male($6.81{\pm}4.56$) and 252 were female($5.94{\pm}4.37$). Hierarchical Multiple Regression revealed that the score of dry mouth was shown to be significantly higher for the following people: Males, who were employed, unemployed, negative self-perceived general health, perceived stress, and participants who had no experience awareness of distress in two weeks. The explanatory power was 21.9%. The most powerful impact factor regarding to employment was shown to be negatively associated to dry mouth, and self-perceived general health, experiencing awareness of distressful in two weeks was also important factors. Conclusions : Based on these results in order to develop oral health education policy strategies for the prevention and management of dry mouth, there need to be considered for the employee.

• Journal of Gastric Cancer
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• v.14 no.4
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• pp.252-258
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• 2014

Purpose: The macroscopic diagnosis of tumor invasion through the serosa during surgery is not always distinct in patients with gastric cancer. The prognostic impact of the difference between macroscopic findings and pathological diagnosis of serosal invasion is not fully elucidated and needs to be re-evaluated. Materials and Methods: A total of 370 patients with locally advanced pT2 to pT4a gastric cancer who underwent curative surgery were enrolled in this study. Among them, 155 patients with pT3 were divided into three groups according to the intraoperative macroscopic diagnosis of serosal invasion, as follows: serosa exposure (SE)(-) (no invasion, 72 patients), SE(${\pm}$) (ambiguous, 47 patients), and SE(+) (definite invasion, 36 patients), and the clinicopathological features, surgical outcomes, and disease-free survival (DFS) were analyzed. Results: A comparison of the 5-year DFS between pT3_SE(-) and pT2 groups and between pT3_SE(+) and pT4a groups revealed that the differences were not statistically significant. In addition, in a subgroup analysis of pT3 patients, the 5-year DFS was 75.1% in SE(-), 68.5% in SE(${\pm}$), and 39.4% in SE(+) patients (P<0.05). In a multivariate analysis to evaluate risk factors for tumor recurrence, macroscopic diagnosis (hazard ratio [HR], SE(-) : SE(${\pm}$) : SE(+)=1 : 1.01 : 2.45, P=0.019) and lymph node metastasis (HR, N0 : N1 : N2 : N3=1 : 1.45 : 2.20 : 9.82, P<0.001) were independent risk factors for recurrence. Conclusions: Gross inspection of serosal invasion by the surgeon had a strong impact on tumor recurrence in gastric cancer patients. Consequently, the gross appearance of serosal invasion should be considered as a factor for predicting patients' prognosis.

• Journal of Distribution Science
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• v.16 no.9
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• pp.25-33
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• 2018

Purpose - The purpose of the study is to analyze the empowerment intermediary role on the relationship between the job distribution and the quality of life. A research on empowerment and social service staffs' job distribution also should be conducted to improve the quality of their lives. Because empowerment, particularly, affects the quality of life, it should be taken a detail discussion for empowerment improvement. Research design, data, and methodology - This paper conducted a questionnaire survey. In total, 722 copies of the structural questionnaire were analyzed. Five parameter subsets were selected to measure the empowerment such as task significance, role performance capability, self-determination, task impact, then, the survey consists of 10 questions. For data analysis, confirmatory factor analysis, discriminant and concentration validity analysis, path coefficient significance, and mediation effectiveness verification were employed. Results - As evidenced from the data analysis, job distribution variables such as job impact, job autonomy, and feedback affect the quality of their lives. Empowerment also affects the quality of their lives. Next, the empowerment functions as meditating role in the relationships with job impact, job autonomy, feedback and the quality of their lives. On the other hand, the empowerment do not function as meditating role in the relationships with social service staffs' function diversity and the quality of their lives. Conclusions - It is necessary to conduct ways for various job performance and outside educational facilities to improve social service staffs' function diversity. The mission, vision, strategic purposes, detailed execution goals need to be set by all their organization members' participation. Empowerment also requires social welfare facilities' drastic delegation on their authority and responsibilities with their active decentralization in the organization.