• 한국대기환경학회지
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• 제14권6호
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• pp.631-642
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• 1998

Fall-out particles were collected by the modified British deposit gauges at 35 sampling sites in Suwon area from January to November, 1996. Twenty chemical species (Al. Ba, Cd, Cr, K, Pb, Sb, Zn, Cu, Fe, Ni, V, F-, Cl-, NO3-, 5042-, Na+, NH4+, Mg2+, and Ca2+) were analyzed by AAS and If. The purposes of this study were to estimate qualitatively various emission sources of the fell-out particle by applying multivariate statistical techniques such as factor analysis, multiple regression analysis, and discriminant analysis. During the study, outlier sites were determined by a z-score method. Cl-, Na+, Mg2+, and SO42- were highly correlated due to their common marine related source. Wind speed was the most influential factor for the deposition fluxes of the particle itself and all the chemical species as well. When applying the factor analysis, 8 source patterns were qualitatively obtained, such as marine source, soil source, oil burning source, Cr related source, tire source, Cd related source, agriculture source, and F- related source. As a result of the multiple regression analysis, we could suggest that some chemical compounds may possibly exist in the form of CaSO4, NaN03, NaCl, MgC12, (NH4)2SO4, NaF, and CaCl2 in the fall-out particles. Finally, spatial and seasonal classification study performed by a discriminant analysis showed th.at SO42-, Ca2+, Cl-, and Fe were dominant in the group of spatial pattern; however, SO42-, Cl-, Al, and V were in the group of seasonal pattern.

• Safety and Health at Work
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• 제7권2호
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• pp.124-129
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• 2016

Background: Work-related fatigue has a strong impact on performance and safety but so far, no agreed upon method exists to detect and quantify it. It has been suggested that work-related fatigue cannot be quantified with just one test alone, possibly because fatigue is not a uniform construct. The purpose of this study is therefore to measure work-related fatigue with multiple tests and then to determine the underlying factorial structure. Methods: Twenty-eight employees (mean: 36.11; standard deviation 13.17) participated in five common fatigue tests, namely, posturography, heart rate variability, distributed attention, simple reaction time, and subjective fatigue before and after work. To evaluate changes from morning to afternoon, t tests were conducted. For further data analysis, the differences between afternoon and morning scores for each outcome measure and participant (${\Delta}$ scores) were submitted to factor analysis with varimax rotation and each factor with the highest-loading outcome measure was selected. The ${\Delta}$ scores from tests with single and multiple outcome measures were submitted for a further factor analysis with varimax rotation. Results: The statistical analysis of the multiple tests determine a factorial structure with three factors: The first factor is best represented by center of pressure (COP) path length, COP confidence area, and simple reaction time. The second factor is associated with root mean square of successive difference and useful field of view (UFOV). The third factor is represented by the single ${\Delta}$ score of subjective fatigue. Conclusion: Work-related fatigue is a multidimensional phenomenon that should be assessed by multiple tests. Based on data structure and practicability, we recommend carrying out further studies to assess work-related fatigue with manual reaction time and UFOV Subtest 2.

• 복식
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• 제66권4호
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• pp.32-44
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• 2016

The purpose of this study is to examine the cognitive responses and the corresponding behavior responses of consumers who have experiences in not being able to buy a product in an online shopping mall due to it being sold-out. Responses were gathered from 526 consumers between the ages of 20 to 40 years residing in a metropolitan area. Each person surveyed had experienced a situation in which a product that they wanted to purchase from an online shopping mall was sold-out. SPSS 18.0 was used to perform frequency analysis, factor analysis, reliability analysis, and regression analysis. The first set of results of this study showed positive responses of quality, discernment, scarcity, but also negative cognitive responses of careless management, manipulation of shopping mall management, and common taste. In negative cognitive responses, sold-out situations caused consumers inconvenience. The second set of results revealed that quality, discernment, and careless management had a significant effect on product replacement (Substitute, S); likewise, factors such as quality, discernment, careless management, manipulation by shopping mall designers, and common taste had a significant effect on the delay of purchasing decisions (Delay, D). Scarcity, careless management, manipulation by shopping mall designers, and common taste also demonstrated significant influence on the incomplete leaving of stores (Incomplete Leave, L1), while discernment, scarcity, careless management, manipulation by shopping mall designers, and common taste had a significant influence on the complete leaving of stores (Complete Leave, L2). Previous studies have examined the behavioral response topics of substitute, delay, and leave. These study results suggest that product sellouts at online shopping malls did not have a solely negative effect on consumers. It actually had a positive effect in terms of discernment, scarcity, and the perception of quality of sold-out products. Furthermore, both positive and negative cognitive responses had various effects on behavioral responses.

• 아동학회지
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• 제6권2호
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• pp.35-58
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• 1985

The purpose of this study was to investigate the components in friendship as reported by Korean children of School age Specially, four major aspects of friendship - definition of friendship, friendship formation, friendship expectation, and friendship termination were explored. The subjects of this study consisted of 600 elementary school children in Grades 1 through 6, 50 males and 50 females at each grade level. Based on Bigelow (1977) five open - ended questions were administered. First and second graders were interviewed individually while 3rd-6th graders replied to a questionnaire in class. For content analysis, responses of each child were coded into 22 categories and each category was assigned a score from 1 to 4 according to its frequency. The data were analyzed by factor analysis. The results showed that four major aspects of friendship in Korean children of school age were found to consist of four different factors. DEFINITION OF FRIENDSHIP was found to consist of the factors; 1) reciprocity of liking vs. helping 2) global evaluation vs helping 3) sharing and 4) common activities. FRIENDSHIP FORMATION was found to consist of the factors; 1) situational effects vs complex evaluation 2) structural dimension vs common activities 3) helping and 4) staring. FRIENDSHIP EXPECTATION was found to consist of the factors; 1) mutuality 2) common activities vs. loyalty & commitment 3) exclusive - dyadic activities vs. admiration (character) and 4) interactive a1truism. FRIENDSHIP TERMINATION was found to consist of the factors; 1) physical separation vs disappointment (character) 2) conflict 3) physical separation vs. psychological dimension and 4) general altruism.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제35권5호
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• pp.287-293
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• 2009

Cell survival is the result of a balance between programmed cell death and cellular proliferation. Cell membrane receptors and their associated signal transducing proteins control these processes. Of the numerous receptors and signaling proteins, epidermal growth factor receptor (EGFR) is one of the most important receptors involved in signaling pathways implicated in the proliferation and survival of cancer cells. EGFR is often highly expressed in human tumors including oral squamous cell carcinomas, and there is increasing evidence that high expression of EGFR is correlated with poor clinical outcome of common human cancers. Therefore, we examined the antiproliferative activity of gefitinib, epidermal growth factor receptor tyrosine kinase inhibitor (EGFR TKI), in head and neck cancer cell lines. SCC-9, KB cells were cultured and growth inhibition activity of gefitinib was measured with MTT assay. To study influence of gefitinib in cell cycle, we performed cell cycle analysis with flow cytometry. Western blot was done to elucidate the expression of EGFR in cell lines and phosphorylation of EGFR and downstream kinase protein, Erk and Akt. Significant growth inhibition was observed in SCC-9 cells in contrast with KB cells. Also, flow cytometric analysis showed G1 phase arrest only in SCC-9 cells. In Western blot analysis for investigation of EGFR expression and downstream molecule phosphorylation, gefitinib suppressed phosphorylation of EGFR and downstream protein kinase Erk, Akt in SCC-9. However, in EGFR positive KB cells, weak expression of active form of Erk and Akt and no inhibitory activity of phosphorylation in Erk and Akt was observed. The antiproliferative activity of gefitinib was not correlated with EGFR expression and some possibility of phosphorylation of Erk and Akt as a predictive factor of gefitinib response was emerged. Further investigations on more reliable predictive factor indicating gefitinib response are awaited to be useful gefitinib treatment in head and neck cancer patients.

• 한국재료학회지
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• 제31권8호
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• pp.450-457
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• 2021

From measured thermal conductivity and modeling by simulation, this study suggests that U-factors are highly related to materials used between steel and polymer. The objective and prospective point of this study are to relate the relationship between the U-factor and the thermal conductivity of the materials used. For the characterization, EDX, SEM, a thermal conductive meter, and computer simulation utility are used to analyze the elemental, surface structural properties, and U-factor with a simulation of the used material between steel and polymer. This study set out to divide the curtain wall system that makes up the envelope into an aluminum frame section and entrance frame section and interpret their thermal performance with U-factors. Based on the U-factor thermal analysis results, the target curtain wall system is divided into fix and vent types. The glass is 24 mm double glazing (6 mm common glass +12 mm Argon +6 mm Low E). The same U-factor of 1.45 W/m²·K is applied. The interpretation results show that the U-factor and total U-value of the aluminum frame section are 1.449 and 2.343 W/m²·K, respectively. Meanwhile, those of the entrance frame section are 1.449 and 2.

• 한국환경과학회지
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• 제28권12호
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• pp.1101-1110
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• 2019

This study investigated Post-Occupancy Evaluation (POE) of cherry blossom trails 'Cherry Road' in Daegu Catholic Univ. campus, at Gyeonsan-city, Korea. The evaluation focused on image preference and satisfaction of users i.e., students, using questionnaire surveys. A total 201 questionnaire samples were analyzed and most of the respondents were in the age group of 20. Frequency analysis was conducted on demographics, use behavior, reliability, and means. Factor analysis and multiple regression analysis were conducted for user satisfaction and image preference. Over 80% of visitors came with companions during daytime. The most common motives for use were strolling and walking, event and meeting, passing. For user satisfaction the mean scores were highest for landscape beauty (4.22), image improvement (4.14), campus image (4.08). Night lighting facility received the lowest score (3.32). Factor analysis concerning user satisfaction was categorized into environment-human behavior and physical factors. Multiple regression analysis showed that the overall satisfaction of user was significantly influenced by five independent variables: 'harmonious' (β=.214), 'night lighting facility' (β=.173), 'landscape beauty' (β=.208), 'lawn care' (β=.154), and 'walking trails' (β=.123). The mean scores of image variables were highest for 'beautiful' (5.81), 'bright' (5.67), and 'open' (5.64). The lowest scores was for 'quiet' (4.47). Exploratory factor analysis led to three factors being categorized: aesthetics, comforts, and simplicity. Result of multiple regression analysis indicated that the preference of space image was significantly influenced by five variables: 'bright' (β=.397), 'refreshing' (β=.211), 'cool' (β=.219), 'clean' (β=.182), and 'natural' (β=.-142). Hence, Cherry Road has a high level of user satisfaction and image evaluation, which is interpreted as having various cultural events and value for students on campus. To improve the satisfaction of Cherry Road in the future, it is necessary to secure night lighting, to manage trash cans, and to secure rest space.

• 대한기관식도과학회지
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• 제17권2호
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• pp.98-103
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• 2011

Purpose Pulmonary complications continue to be the major cause of morbidity and mortality after esophageal resection. The aim of this study was to compare and analyze retrospectively the factors which effect for postoperative pulmonary complications in patients who underwent curative resection for esophageal cancer. Material and Method A total of 118 patients were enrolled in the study from January 1994 to March 2009, and patients with previous neoadjuvant chemotherapy or radiotherapy were excluded. Of the total 118 patients, 27 patients developed pulmonary complications within 30 days of their operation. the factors which effect for postoperative pulmonary complications were compared and analyzed. Results There were 7 patients in-hospital deaths. 51 patients (43.2%) developed complications, and of them, the most common complication was pulmonary complication and occurred in 27 patients (22.9%). In univariate analysis, diabetes mellitus, cervical anastomosis through the retrosternal route, old age and poor lung function were risk factors contributing to postoperative pulmonary complications (p<0.05). In multivariate analysis, statistically significant factor was old age (65 years or older). Conclusion Clinical factor for the pulmonary complications after esophagectomy of esophageal cancer was significantly associated with diabetes mellitus, cervical anastomosis through the retrosternal route, old age (65 years or older) and poor lung function (FEV1<80%). Of these, old age was the most significant factor.

• 한국의류학회지
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• 제34권6호
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• pp.902-912
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• 2010

This study compares and contrasts the consumer decision-making styles (CDMS) of South Korean and American Generation Y females. A total of 117 American female and 206 Korean female consumers completed self-report survey questionnaires to assess their consumer decision making styles. Exploratory principal components factor analysis using varimax rotation was used to categorize the items into an underlying set of American and Korean decision-making characteristics. Two-tailed independent t-tests were conducted to examine the differences between the two groups when items appeared to have common factors. Factor analysis identified five common factors between the two samples (i.e., enjoyment, shopping aversion, price consciousness, brand consciousness, and quality consciousness). The t-test results report significant differences in the items reported in each factor between American and Korean females. Some of the factors are more indicative of American female Generation Y consumers than Korean female Generation Y consumers. For example, the American female sample seemed to enjoy shopping and prefer brand names more than the female Korean sample. Koreans females seem to have a higher aversion to shopping than Americans; in addition, Koreans females seem to be more accepting of discount and outlet stores, will wait until the price is low before buying a product, and prefer sales when shopping. Based on the findings, the instrument identified varying CDMS between the two samples used. Previous studies using the Sproles and Kendall (1986) instrument experienced the same issue (Bakewell & Mitchell, 2004, 2006; Bauer et al., 2006; Durvasula et al., 1996; Fan & Xiao, 1998; Hanzaee & Aghasibeig, 2008; Mitchell & Walsh, 2004; Siu et al., 2001; Walsh et al., 2001). The results support the idea that no single instrument can be used to examine CDMS in different cultures. This suggests that each country has a CDMS with internal characteristics. Limitations and research for future studies are also discusse.

• 산경연구논집
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• 제12권2호
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• pp.41-52
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• 2021

Purpose: This study aims to provide implications for the government's housing supply policy by analyzing the factors that determine the type of real estate holding and household debt. This study started from the awareness that the determinants of household debt differ depending on the type of real estate holding. Research design, data and methodology: Real estate ownership type was classified and analyzed into 4 models: model 1 (1 household 1 house and self-resident), model 2 (1 household multiple real estate ownership and self-resident), model 3 (1 household 1 house and rent residence), model 4 (1 household holds a large number of real estate and rent residence). The analysis method used multiple regression analysis. The dependent variable was household total debt. As independent variables, household debt, annual gross household income, financial assets, real estate net assets, annual repayment, demographic & residential characteristics were used. Results: 1) Model 4 has the highest household debt and the highest gross income, Model 2 has the most real estate mortgage loans and real estate net asset, and Model 1 has the highest real estate mortgage payments. 2) The positive factor of common household debt determinants is real estate net assets, and the negative factor is financial assets. 3) It was the net assets of real estate that acted as a positive factor in common for the four models. In other words, the more financial assets, the less household debt. It was analyzed that the more net assets of real estate, the more household debt. The annual repayment of financial liabilities had no influence on household debt, while the annual repayment of loan liabilities and household debt had a positive relationship. Conclusions: 1) It is necessary to introduce benefits and systems that can increase the proportion of household financial asset. Specific alternatives include tax benefits and reduced fees for financial asset investment. 2) In the case where a homeless person prepares one house for one household, it is necessary to prepare various support measures according to the income level. The specific alternative is to give additional points for pre-sale or apply an interest rate cut incentive for mortgage loans.