• KSCE Journal of Civil and Environmental Engineering Research
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• v.42 no.1
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• pp.95-105
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• 2022

Recently, as the scale of a construction project has become larger and more complicated, there are many cases where construction projects with complex structures are carried out in a fast track method to save construction duration. In the fast track method, the proper division of construction phases is an important issue in determining the overall project period. This study presents a rational phase division method that can be applied when a construction project with complex structures is carried out as a fast track. For this study, a subdivided work breakdown structure (WBS) is developed using the construction of 4 soccer stadiums as application examples, and the schedule is analyzed by dividing the construction process of major phases. To this end, five proposals are applied to analyze the adequacy of the fast track phase division. For the draft with the minimum construction period, the fast track phase division and the schedule model of by each phase were presented. This methodology can have an application in the appropriate phase division and schedule model by construction phase when fast track is applied in large construction project of a similar size.

• Journal of Intelligence and Information Systems
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• v.19 no.2
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• pp.39-54
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• 2013

Recent explosive increase of electronic commerce provides many advantageous purchase opportunities to customers. In this situation, customers who do not have enough knowledge about their purchases, may accept product recommendations. Product recommender systems automatically reflect user's preference and provide recommendation list to the users. Thus, product recommender system in online shopping store has been known as one of the most popular tools for one-to-one marketing. However, recommender systems which do not properly reflect user's preference cause user's disappointment and waste of time. In this study, we propose a novel recommender system which uses data mining and multi-model ensemble techniques to enhance the recommendation performance through reflecting the precise user's preference. The research data is collected from the real-world online shopping store, which deals products from famous art galleries and museums in Korea. The data initially contain 5759 transaction data, but finally remain 3167 transaction data after deletion of null data. In this study, we transform the categorical variables into dummy variables and exclude outlier data. The proposed model consists of two steps. The first step predicts customers who have high likelihood to purchase products in the online shopping store. In this step, we first use logistic regression, decision trees, and artificial neural networks to predict customers who have high likelihood to purchase products in each product group. We perform above data mining techniques using SAS E-Miner software. In this study, we partition datasets into two sets as modeling and validation sets for the logistic regression and decision trees. We also partition datasets into three sets as training, test, and validation sets for the artificial neural network model. The validation dataset is equal for the all experiments. Then we composite the results of each predictor using the multi-model ensemble techniques such as bagging and bumping. Bagging is the abbreviation of "Bootstrap Aggregation" and it composite outputs from several machine learning techniques for raising the performance and stability of prediction or classification. This technique is special form of the averaging method. Bumping is the abbreviation of "Bootstrap Umbrella of Model Parameter," and it only considers the model which has the lowest error value. The results show that bumping outperforms bagging and the other predictors except for "Poster" product group. For the "Poster" product group, artificial neural network model performs better than the other models. In the second step, we use the market basket analysis to extract association rules for co-purchased products. We can extract thirty one association rules according to values of Lift, Support, and Confidence measure. We set the minimum transaction frequency to support associations as 5%, maximum number of items in an association as 4, and minimum confidence for rule generation as 10%. This study also excludes the extracted association rules below 1 of lift value. We finally get fifteen association rules by excluding duplicate rules. Among the fifteen association rules, eleven rules contain association between products in "Office Supplies" product group, one rules include the association between "Office Supplies" and "Fashion" product groups, and other three rules contain association between "Office Supplies" and "Home Decoration" product groups. Finally, the proposed product recommender systems provides list of recommendations to the proper customers. We test the usability of the proposed system by using prototype and real-world transaction and profile data. For this end, we construct the prototype system by using the ASP, Java Script and Microsoft Access. In addition, we survey about user satisfaction for the recommended product list from the proposed system and the randomly selected product lists. The participants for the survey are 173 persons who use MSN Messenger, Daum Caf$\acute{e}$, and P2P services. We evaluate the user satisfaction using five-scale Likert measure. This study also performs "Paired Sample T-test" for the results of the survey. The results show that the proposed model outperforms the random selection model with 1% statistical significance level. It means that the users satisfied the recommended product list significantly. The results also show that the proposed system may be useful in real-world online shopping store.

• Korean Journal of Adult Nursing
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• v.21 no.6
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• pp.580-592
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• 2009

Purpose: The purpose of this study was to investigate the factors related to Breast cancer Screening using Mammography and CBE of Korean women over 40 years of age. Methods: The participants for this study were 183 Korean women living in 3 urban cities and aged from 40 to 75. The data were collected using structured questionnaires which included sociodemographic factors (11 items), frequency and regularity of mammography and clinical breast examination (7 items), knowledge (16 items), health belief model scale (28 items), and family support (4 items) about breast cancer and breast cancer screening. Frequencies, Chronbach's alpha for reliability, Chi-square, t-test and logistic regression with the SPSS/WIN 12 program were used to analyze the data. Results: The percentages of Korean women who had a mammography and CBE for breast cancer screening were 60.1 and 31.1, respectively. Logistic regression analyses demonstrated that regular check ups and perceived barriers were significant predictors of mammography and CBE use for breast cancer screening. Conclusion: In order to increase the frequency of breast cancer screening practices, educational support and a health care delivery system is needed to improve the chance of regular health check ups.

• Research in Community and Public Health Nursing
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• v.31 no.1
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• pp.13-23
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• 2020

Purpose: This study explored the contribution of social support resources to the explanation of socioeconomic inequalities in depressive symptoms of older Korean men and women. Methods: Data were derived from Living Profiles of Older People Survey (LPOPS), which comprises a nationally representative sample of non-institutionalized Korean older adults living in the community. The data were analyzed by using multiple logistic regression. The sample consisted of 4,046 men and 6,036 women aged ≥65 years. The Korean version of the Geriatric Depression Scale-Short form (SGDS-K) was employed as an outcome variable. Results: Compared to the older men and women who were in higher socioeconomic status, those in lower socioeconomic status had significantly higher risk of depressive symptoms after adjusting for other covariates. When social support resources were individually included in the base model, each factor contributed to inequalities in depressive symptoms. Social networks explained about 20% of the differential impact of education and 10% to 15% of the differential impact of household income for depressive symptoms in men. Among women, it mitigated 23.6% to 39.0% of education and household income inequalities for depressive symptoms. Social participation contributed to buffer depressive symptom inequalities of 24.0% to 46.3% among men and those of 11.7% to 45.3% among women. Conclusion: Our findings suggest community care nurses acknowledge the value of social support resources to alleviate socioeconomic inequality in depressive symptoms among older men and women.

• Journal of the Korean Society of Clothing and Textiles
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• v.34 no.1
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• pp.112-125
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• 2010

A Holter monitor is used for ECG monitoring of ambulatory daily life in hospital. However, the use of this apparatus causes skin allergies and discomfort in patients because of the attachment gel and tapes used to attach disposable electrodes to the skin. In this study, the development of tight-fitting clothing connected to a portable Holter monitor was proposed. In addition, the use of conductive fabrics as electrodes was proposed; this will enable the use of garments in u-health care for measuring ECG signals. The male subjects were university students in the ages of 20 to 24. Subjective wear sensations of the experimental garments were rated using seven Likert scales. A Likert type scale was used for the evaluation and a 7 point score indicates that it provided the best fit as a tight-fitting upper clothing. Clothing pressure was measured using an air-pack-type pressure sensor (model AMI 3037-2) at 4 locations (the conductive fabric electrode) As results, a male basic sloper for upper clothing was developed and that pattern was manipulated to the tight fit pattern by considering the reduction rate of the percentage stretch in the fabric. The developed tight-fitting garment was superior in terms of subjective sensation and 6t. The mean pressure of the garment with reduction rates of 40% in width and of 50% in length was 8.45gf/$cm^2$. A conductive fabric electrode was developed by considering the sewing method and the developed electrode was detected well. The ECG data were recorded for 13 hr 19 min 44 sec and the artifacts in the ECG signals were recorded for 9 hr 3 min 46 sec (total time: 22 hr 23 min 23 sec). The artifacts data were obtained during heavy activities.

• Research in Community and Public Health Nursing
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• v.10 no.2
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• pp.362-371
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• 1999

This study was conducted to explore the relationship between locus of control and health belief. the life style of gastric cancer patients. The subjects of this study were 40 of the early gastric cancer and 90 of the advanced gastric cancer who first visiting patient to general surgery out patient department of Chungnam University Hospital for operation. The data was collected with structured questionnaire from July. 1998 to Feb. 1999 The tool were Moon's Health Belief Scale and Multiple Locus of Control of Wallston. Wallston, DeVellis. The data was analysed by SAS program using frequency, $X^2$-test, Pearson's correlation coefficient, ANOVA. Scheffe-test, t-test. The results were as follows 1. 30.8% of subjects were early gastric cancer anf 69.2% were advanced gastric cancer. The subject knowing about diagnosis was 83.1%. 16.9% did'nt know about diagnosis. 2. The correlationship between Health belief and Locus of control of subjects was not supported. 3. There was statistically no difference of life style between early and advanced gastric cancer patients. 4. There were statistically significant differences in perceived sensitivity according to weight. educational level. and birth order, in perceived barrier according to educational level. and in perceived severity according to occupation among demographic characteristics of study subjects. From above results. health professional has to educate general population to detect gastric cancer early to improve survival rate because early gastric cancer is high in survival rate, and to prevent recurrence and to maintain continuing healthy status. In the future, gastroscopy also has to expand to detect early. For there was no difference in life style between early and advanced gastric cancer. carcinogen related to diet should be emphasized through education. The perceived benefit among health belief model was not supported in this study therefore further study and comparison between gastric cancer and normal population are needed.

• Journal of Environmental Science International
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• v.16 no.8
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• pp.921-928
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• 2007

The objective of this work is the air quality modeling according to the scenarios of emission on complex terrain. The prognostic meteorological fields and air quality field over complex areas of Seoul, Korea are generated by the PSU/NCAR mesoscale model (MM5) and the Third Generation Community Multi-scale Air Quality Modeling System (Models - 3/CMAQ), respectively. The emission source was driven from the Clean Air Policy Support System of the Korea National institute of Environmental Research (CAPSS), which is a 1 km x 1 km grid in South Korea during 2003. In comparison of air quality fields, the simulated averaged $PM_{10},\;NO_2,\;and\;O_3$ concentration on complex terrain in control case were decreased as compared with base case. Particularly $PM_{10}$ revealed most substantial localized differences by $(18{\sim}24{\mu}g/m^3)$. The reduction rate of $PM_{10},\;NO_2,\;and\;O_3$ is respectively 18.88, 13.34 and 4.17%.

• Journal of Korean Neurosurgical Society
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• v.61 no.1
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• pp.10-18
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• 2018

Objective : To investigates the effect of curcumin on proliferation of spinal cord neural stem/progenitor cells (SC-NSPCs) and functional outcome in a rat spinal cord injury (SCI) model. Methods : Sixty adult male Sprague-Dawley rats were randomly and blindly allocated into three groups (sham control group; curcumin treated group after SCI; vehicle treated group after SCI). Functional recovery was evaluated by the Basso, Beattie, and Bresnahan (BBB) scale during 6 weeks after SCI. The expression of SC-NSPC proliferation and astrogliosis were analyzed by nestin/Bromodeoxyuridine (BrdU) and Glial fibrillary acidic protein (GFAP) staining. The injured spinal cord was then examined histologically, including quantification of cavitation. Results : The BBB score of the SCI-curcumin group was better than that of SCI-vehicle group up to 14 days (p<0.05). The coimmunoreactivity of nestin/BrdU in the SCI-curcumin group was much higher than that of the SCI-vehicle group 1 week after surgery (p<0.05). The GFAP immunoreactivity of the SCI-curcumin group was remarkably lower than that of the SCI-vehicle group 4 weeks after surgery (p<0.05). The lesion cavity was significantly reduced in the curcumin group as compared to the control group (p<0.05). Conclusion : These results indicate that curcumin could increase the expression of SC-NSPCs, and reduce the activity of reactive astrogliosis and lesion cavity. Consequently curcumin could improve the functional recovery after SCI via SC-NSPC properties.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.45-48
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• 2009

This study evaluated the influence of temperature on the PV module surface on power output characteristics, especially for an amorphous transparent thin-film PV module which was applied to a full-scale mock-up model as building integrated photovoltaic system. The tested mock-up consisted of various slopes of PV module, facing to the south. The annual average temperature of the module installed with the slope of $30^{\circ}$ revealed $43.1^{\circ}C$, resulting in $7^{\circ}C$ higher than that measured in PV modules with the slope of $0^{\circ}$and $90^{\circ}$ did. This $30^{\circ}$ inclined PV module also showed the highest power output of 28.5W (measured at 2 PM) than other two modules having the power output of 20.4W and 14.9W in the same time for $0^{\circ}$ and $90^{\circ}$ in the slope, respectively. In case of the $30^{\circ}$ inclined PV module, it exhibited very uniform distribution of power output generation even under the higher temperature on the module surface. Consequently, the surface temperature of the PV module analyzed in this study resulted in 0.22% reduction in power output in every $1^{\circ}C$ increase of the module surface temperature.

• Journal of Advanced Navigation Technology
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• v.15 no.1
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• pp.140-146
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• 2011

In this paper, we propose a fast object classification method based on texture and color information for video surveillance. We take the advantage of local patches by extracting SURF and color histogram from images. SURF gives intensity content information and color information strengthens distinctiveness by providing links to patch content. We achieve the advantages of fast computation of SURF as well as color cues of objects. We use Bag of Word models to generate global descriptors of a region of interest (ROI) or an image using the local features, and Na$\ddot{i}$ve Bayes model for classifying the global descriptor. In this paper, we also investigate discriminative descriptor named Scale Invariant Feature Transform (SIFT). Our experiment result for 4 classes of the objects shows 95.75% of classification rate.