• Journal of Intelligence and Information Systems
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• v.24 no.2
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• pp.85-109
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• 2018

Recommender system recommends the items expected to be purchased by a customer in the future according to his or her previous purchase behaviors. It has been served as a tool for realizing one-to-one personalization for an e-commerce service company. Traditional recommender systems, especially the recommender systems based on collaborative filtering (CF), which is the most popular recommendation algorithm in both academy and industry, are designed to generate the items list for recommendation by using 'overall rating' - a single criterion. However, it has critical limitations in understanding the customers' preferences in detail. Recently, to mitigate these limitations, some leading e-commerce companies have begun to get feedback from their customers in a form of 'multicritera ratings'. Multicriteria ratings enable the companies to understand their customers' preferences from the multidimensional viewpoints. Moreover, it is easy to handle and analyze the multidimensional ratings because they are quantitative. But, the recommendation using multicritera ratings also has limitation that it may omit detail information on a user's preference because it only considers three-to-five predetermined criteria in most cases. Under this background, this study proposes a novel hybrid recommendation system, which selectively uses the results from 'traditional CF' and 'CF using multicriteria ratings'. Our proposed system is based on the premise that some people have holistic preference scheme, whereas others have composite preference scheme. Thus, our system is designed to use traditional CF using overall rating for the users with holistic preference, and to use CF using multicriteria ratings for the users with composite preference. To validate the usefulness of the proposed system, we applied it to a real-world dataset regarding the recommendation for POI (point-of-interests). Providing personalized POI recommendation is getting more attentions as the popularity of the location-based services such as Yelp and Foursquare increases. The dataset was collected from university students via a Web-based online survey system. Using the survey system, we collected the overall ratings as well as the ratings for each criterion for 48 POIs that are located near K university in Seoul, South Korea. The criteria include 'food or taste', 'price' and 'service or mood'. As a result, we obtain 2,878 valid ratings from 112 users. Among 48 items, 38 items (80%) are used as training dataset, and the remaining 10 items (20%) are used as validation dataset. To examine the effectiveness of the proposed system (i.e. hybrid selective model), we compared its performance to the performances of two comparison models - the traditional CF and the CF with multicriteria ratings. The performances of recommender systems were evaluated by using two metrics - average MAE(mean absolute error) and precision-in-top-N. Precision-in-top-N represents the percentage of truly high overall ratings among those that the model predicted would be the N most relevant items for each user. The experimental system was developed using Microsoft Visual Basic for Applications (VBA). The experimental results showed that our proposed system (avg. MAE = 0.584) outperformed traditional CF (avg. MAE = 0.591) as well as multicriteria CF (avg. AVE = 0.608). We also found that multicriteria CF showed worse performance compared to traditional CF in our data set, which is contradictory to the results in the most previous studies. This result supports the premise of our study that people have two different types of preference schemes - holistic and composite. Besides MAE, the proposed system outperformed all the comparison models in precision-in-top-3, precision-in-top-5, and precision-in-top-7. The results from the paired samples t-test presented that our proposed system outperformed traditional CF with 10% statistical significance level, and multicriteria CF with 1% statistical significance level from the perspective of average MAE. The proposed system sheds light on how to understand and utilize user's preference schemes in recommender systems domain.

• Journal of Acupuncture Research
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• v.33 no.2
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• pp.61-76
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• 2016

Objectives : This study was designed to clarify population-social characteristics that influence the utilization patterns of hospitalized patients in a traditional korean hospital, thereby providing clinical data which would help further improvements of traditional korean medical service in particular the Acupuncture and Moxibustion. Methods : We investigated population-social characteristics and annual utilization patterns of all patients who were hospitalized for more than 24 hours in a Korean Medical Hospital from January 2005 to December 2014. The obtained data were recorded in the EMR chart and statistical analysis was performed using SPSS 21.0. Additionally, data from the patients admitted to the department of Acupuncture and Moxibustion were analyzed separately. Results : 1. All inpatients had a significant annual difference in age, gender, hospitalized department, and disease code annually but not in re-hospitalization number. Inpatients of the department of Acupuncture and Moxibustion also varied in their age, gender, and disease code annually, but not in re-hospitalization number. 2. Pearson correlation analysis on all inpatients showed that the mean days of hospital treatments had a negative correlation with all variables except medical care insurance. Total cost, cost per day per person and recuperation cost had a positive correlation with all variables except medical care insurance. There was no meaningful relationship between nonrecuperation cost and the variables. 3. Stepwise multiple regression analysis on all inpatients showed that the mean days of hospital treatments had a negative correlation with all variables except automobile insurance. The total hospitalization costs had a positive correlation with both general insurance and medical care insurance. Cost per day per person and recuperation cost had a positive correlation with the females. There was no meaningful relationship between non-recuperation cost and the variables. 4. Pearson correlation analysis on inpatients of the department of Acupuncture and Moxibustion inpatients showed that the mean days of hospital treatments had a positive correlation with all variables except general insurance and automobile insurance. Total cost and recuperation cost had a positive correlation with all variables except medical care insurance, and cost per day per person had a positive correlation with females and general insurance. There was no meaningful relationship between non-recuperation cost and the variables. 5. Stepwise multiple regression analysis on inpatients of the department of Acupuncture and Moxibustion inpatients, the mean days of hospital treatments, total cost, cost per day per person and recuperation cost had a positive correlation with general insurance. There was no meaningful relationship between non-recuperation cost and the variables. Conclusion : Population-social characteristics of inpatients annually varies, and the change influences the utilization pattern.

• The Journal of Pediatrics of Korean Medicine
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• v.14 no.1
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• pp.9-38
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• 2000

It has been widely said in Korea that early administrations of Cervi cornu parvum (deer antler) to febrile infants affect brain functions. Traditional Oriental Medicine states that the head is easily affected by fever and only an excess of heat causes headaches. Traditional Oriental Medicine also states that Cervi cornu parvum cannot be used in febrile conditions. With the aim of investigating different febrile response to LPS, experiments using intravenous injection of LPS have been carried out on Cervi comu parvum(CCP) and Soahbohyul - tang combined with Cervi comu parvum(SB-CCP) administered rabbits. Experiments were also conducted to evaluate the effects of early administration of CCP on learning and memory in 3 week old rats with LPS fever. These were evaluated by using the Morris water maze and the radial arm maze. Changes in body weight were also observed during this period. The results of these experiments are as follows. 1. In the experiments with febrile rabbits, the CCP and SB-CCP administered group showed statistically significant reductions of fever (p<0.05). 2. In the experiments with febrile rabbits, CCP and SB-CCP administered rabbits resulted in the tendency of lower body temperatures and shorter fever periods than the control group. 3. There were no differences of mean body weight and fever patterns among the 4 groups in the experiments on young rats with LPS fever. 4. There was no statistical difference of mean response latencies among the rats in Group I (DDW administered), GroupIII (CCP administered), and groupIV (SB-CCP administered) in the Morris water maze. However, Group Ⅱ (the scopolamine administered group) showed delayed latencies on the second day of the first session (p<0.05), and the second and third day of the second session (p< 0.05). 5. There were no statistical differences of mean response latencies among the rats in Group I, III and Ⅳ in the radial arm maze, but Group Ⅱ showed delayed latencies on the first and third day of the first session (p<0.05). 6. There was no influence from the administration of CCP and SB-CCP on the general behavior of the rats in Irwin´s test. These results suggest that Cervi cornu parvum and Soahbohyul - tang combined with Cervi comu parvum have anti-pyretic actions on LPS fever. The results also suggest that these drugs have no influence on learning and memory in young rats with LPS fever in the Morris water maze and the radial arm maze.

• Journal of the Korean Data and Information Science Society
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• v.24 no.3
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• pp.515-521
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• 2013

Healthcare approach in Western medicine and Korean Traditional Medicine (KTM) varies from its nature of human understanding and cultural differences. This fundamental difference in their approach of the human pathology has dualised and hindered common medical communication between the two fields of medicines. Within this current difficulty, the integrative medical service is said to become a novel method to provide the patients with the best medical care as their intent is to adapt and combine the advantages stated from the two different fields. This research paper shows the integrative approach of treating jaundice, where the symptoms of dampness and heat on Korean traditional standards are analyzed using statistical methods based on monitoring the blood test results. Therefore, we can explore an approach to diagnose and treat with comprehensive and integrative medicine algorithm.

• Journal of Families and Better Life
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• v.25 no.5
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• pp.143-166
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• 2007

This study examined the effects of employees' gender role attitudes, job involvement, and family involvement on their work-family conflicts, work-family facilitation, and utilization of family-friendly corporate policies. Data was collected from 377 full-time married workers from 262 large (more than 300 employees) and 100 small (fewer than 300 employees) private sector companies. The questionnaire's measurements were based on recommendations from the literature review. The questionnaire consisted of the gender role attitude scales, job and family involvement scales, work-family conflict and facilitation scales, and questions pertaining to the employee's utilization of family-friendly corporate policies. The SPSS 12.0 statistical package was used to analyze the collected data. The study found that employees showed more or less egalitarian gender role attitudes and that they were more involved in their family than their job. The employees' responses showed a low rate of utilizing family-friendly policies, but employees from large companies reported a higher utilization of family-friendly policies than those from small companies. There were also gender differences in employees' gender role attitudes, work and family involvement, and utilization of policies. Male workers held more traditional gender role attitudes, had higher levels of job involvement, and had higher rates of utilization of policies than female employees. Meanwhile, employees with children exhibited more traditional gender role attitudes and higher rates of utilization of policies than those without children. Finally, serial hierarchical regression analyses revealed that employees' more egalitarian gender role attitudes and higher job and family involvement predict higher work-family facilitation, while their gender role attitudes and job and family involvement have no significant influence on work-family conflicts. Also, employees from large companies with high job involvement will have significantly higher utilization rates of family-friendly corporate policies.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.6
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• pp.2889-2909
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• 2017

Wireless sensor networks (WSNs) have attracted lots of attention in recent years due to their potential for various applications. In this paper, we seek how to efficiently deploy relay nodes into traditional static WSNs with constrained locations, aiming to satisfy specific requirements of the industry, such as average energy consumption and average network reliability. This constrained relay node deployment problem (CRNDP) is known as NP-hard optimization problem in the literature. We consider addressing this multi-objective (MO) optimization problem with an improved Artificial Bee Colony (ABC) algorithm with a linear local search (MOABCLLS), which is an extension of an improved ABC and applies two strategies of MO optimization. In order to verify the effectiveness of the MOABCLLS, two versions of MO ABC, two additional standard genetic algorithms, NSGA-II and SPEA2, and two different MO trajectory algorithms are included for comparison. We employ these metaheuristics on a test data set obtained from the literature. For an in-depth analysis of the behavior of the MOABCLLS compared to traditional methodologies, a statistical procedure is utilized to analyze the results. After studying the results, it is concluded that constrained relay node deployment using the MOABCLLS outperforms the performance of the other algorithms, based on two MO quality metrics: hypervolume and coverage of two sets.

• Korean Journal of Construction Engineering and Management
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• v.4 no.4 s.16
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• pp.192-200
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• 2003

The object of this research is to develop a computerized algorithm of cost estimation method to forecast the total construction cost in the bidding stage by the historical and elemental work cost data. Traditional cost models to prepare Bill of Quantities in the korea construction industry since 1970 are not helpful to forecast the project total cost in the bidding stage because the BOQ is always constant data according to the design factors of a particular project. On the contrary, statistical models can provide cost quicker and more reliable than traditional ones if the collected cost data are sufficient enough to analyze the trends of the variables. The estimation system considers non-deterministic methods which referred to as the 'Monte Carlo simulation. The method interprets cost data to generate a probabilistic distribution for total costs from the deficient elemental experience cost distribution.

• The Korean Journal of Community Living Science
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• v.15 no.3
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• pp.21-28
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• 2004

Marketing of traditional doenjang (a kind of fermented soybean product) is now focusing on its health advantages, being proven to have anti-viral, anti-cancer and anti-oxidant effects. The purpose of this study is to investigate the consumption patterns of traditional doenjang in the households managed by different generations of women living in Gyeonggi area. Six hundred housewives answered the questionnaire. Statistical analyses were performed on 590 subjects using SAS (ver 8.1). Chi-square tests and General Linear Models were used. The age distribution of housewives was as follows: 42.9% were in their 30s; 40.9% were in their 40s; and 16.2% were in their 50s. 57.5% of subjects graduated with high school education while 72.8% of subjects did housework only. Overall, 47.2%, prepared their doenjang themselves, while the remainder purchased it or received it from relatives. This percentage differed however according to age group, as self-preparation of doenjang was found in only 22% of housewives in their 30s, but increased to 83% of subjects in their 50s. 53.4% of subjects had their doenjang donated to them by relatives, compared with only 3.1 % of subjects in their 50s. Most of dishes using doenjang were soups and stews. Those housewives in their 50s made significantly higher use of doenjang in soup, wrapping vegetables (ssamjang), seasoning, and flat cake (jangttok). Doenjang dishes were prepared for the husband in the family 59.2% of the time, followed by housewives 15.4% of the time. Annual consumption of doenjang was 5.1kg. and Kanjang was 4.4L per household; there was no significant difference between the age groups respecting annual consumption. From such results, we may assume a decrease in home-made doenjang among younger generations and an increase in the amount of purchased doenjang. We can predict an increased need for doenjang of better quality. Also the development of new products such as ready-to-eat or fast food variants would better serve the trend towards convenience.

• 한국공간정보시스템학회:학술대회논문집
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• 2007.06a
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• pp.246-251
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• 2007

The purpose of this study is to develop a grid based model for calculating the critical nonpoint source (NPS) pollution load (BOD, TN, TP) in Nak-dong area in South Korea. In the last two decades, NPS pollution has become a topic for research that resulted in the development of numerous modeling techniques. Watershed researchers need to be able to emphasis on the characterization of water quality, including NPS pollution loads estimates. Geographic Information System (GIS) has been designed for the assessment of NPS pollution in a watershed. It uses different data such as DEM, precipitation, stream network, discharge, and land use data sets and utilizes a grid representation of a watershed for the approximation of average annual pollution loads and concentrations. The difficulty in traditional NPS modeling is the problem of identifying sources and quantifying the loads. This research is intended to investigate the correlation of NPS pollution concentrations with land uses in a watershed by calculating Expected Mean Concentrations (EMC). This work was accomplished using a grid based modelling technique that encompasses three stages. The first step includes estimating runoff grid by means of the precipitation grid and runoff coefficient. The second step is deriving the gird based model for calculating NPS pollution loads. The last step is validating the gird based model with traditional pollution loads calculation by applying statistical t-test method. The results on real data, illustrate the merits of the grid based modelling approach. Therefore, this model investigates a method of estimating and simulating point loads along with the spatially distributed NPS pollution loads. The pollutant concentration from local runoff is supposed to be directly related to land use in the region and is not considered to vary from event to event or within areas of similar land uses. By consideration of this point, it is anticipated that a single mean estimated pollutant concentration is assigned to all land uses rather than taking into account unique concentrations for different soil types, crops, and so on.

• Journal of the Korea Fashion and Costume Design Association
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• v.7 no.2
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• pp.11-24
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• 2005

The purpose of this study was to obtain and offer useful information on innerwear industry through an analysis of consumer purchasing behavior and preference of their between the 20's and 60's. From 310 questionnaires that were distributed, 310 with usable data were coded for further statistical analysis including descriptive statistics(frequency and chi-square test), by using SPSSWIN 10.0. The results were as follows: The results show that since the surveyed women's purchasing patterns were varied according to their ages it is necessary to develop new items and designs tailored for particular needs and wants of each age group. For those in their 20's, it is suggested that the innerwear design may consider reflecting the trend of the young women nowadays as characterized by a major fashion-led group who regard fashion as a way of expressing themselves and are not hesitant to wear clothing designed to be exposed their body. The innerwear products for women in their 30's and 40's should emphasize on the aspects of customizing and satisfying these women's different lifestyles. The study also reveal that for age groups of the 50's and 60's women these products should be developed in a way to intensify functions of thermal property and absorbency coupled with a classic design rather than daring styles. In conjunction with material developments it is necessary to establish a sizing system for the knitted innerwear products which reflect the specific characteristics of women's body type in their middle-and later years.