• Journal of Intelligence and Information Systems
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• v.19 no.2
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• pp.1-20
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• 2013

Nowadays, social network is a huge communication platform for providing people to connect with one another and to bring users together to share common interests, experiences, and their daily activities. Users spend hours per day in maintaining personal information and interacting with other people via posting, commenting, messaging, games, social events, and applications. Due to the growth of user's distributed information in social network, there is a great potential to utilize the social data to enhance the quality of recommender system. There are some researches focusing on social network analysis that investigate how social network can be used in recommendation domain. Among these researches, we are interested in taking advantages of the interaction between a user and others in social network that can be determined and known as social relationship. Furthermore, mostly user's decisions before purchasing some products depend on suggestion of people who have either the same preferences or closer relationship. For this reason, we believe that user's relationship in social network can provide an effective way to increase the quality in prediction user's interests of recommender system. Therefore, social relationship between users encountered from social network is a common factor to improve the way of predicting user's preferences in the conventional approach. Recommender system is dramatically increasing in popularity and currently being used by many e-commerce sites such as Amazon.com, Last.fm, eBay.com, etc. Collaborative filtering (CF) method is one of the essential and powerful techniques in recommender system for suggesting the appropriate items to user by learning user's preferences. CF method focuses on user data and generates automatic prediction about user's interests by gathering information from users who share similar background and preferences. Specifically, the intension of CF method is to find users who have similar preferences and to suggest target user items that were mostly preferred by those nearest neighbor users. There are two basic units that need to be considered by CF method, the user and the item. Each user needs to provide his rating value on items i.e. movies, products, books, etc to indicate their interests on those items. In addition, CF uses the user-rating matrix to find a group of users who have similar rating with target user. Then, it predicts unknown rating value for items that target user has not rated. Currently, CF has been successfully implemented in both information filtering and e-commerce applications. However, it remains some important challenges such as cold start, data sparsity, and scalability reflected on quality and accuracy of prediction. In order to overcome these challenges, many researchers have proposed various kinds of CF method such as hybrid CF, trust-based CF, social network-based CF, etc. In the purpose of improving the recommendation performance and prediction accuracy of standard CF, in this paper we propose a method which integrates traditional CF technique with social relationship between users discovered from user's behavior in social network i.e. Facebook. We identify user's relationship from behavior of user such as posts and comments interacted with friends in Facebook. We believe that social relationship implicitly inferred from user's behavior can be likely applied to compensate the limitation of conventional approach. Therefore, we extract posts and comments of each user by using Facebook Graph API and calculate feature score among each term to obtain feature vector for computing similarity of user. Then, we combine the result with similarity value computed using traditional CF technique. Finally, our system provides a list of recommended items according to neighbor users who have the biggest total similarity value to the target user. In order to verify and evaluate our proposed method we have performed an experiment on data collected from our Movies Rating System. Prediction accuracy evaluation is conducted to demonstrate how much our algorithm gives the correctness of recommendation to user in terms of MAE. Then, the evaluation of performance is made to show the effectiveness of our method in terms of precision, recall, and F1-measure. Evaluation on coverage is also included in our experiment to see the ability of generating recommendation. The experimental results show that our proposed method outperform and more accurate in suggesting items to users with better performance. The effectiveness of user's behavior in social network particularly shows the significant improvement by up to 6% on recommendation accuracy. Moreover, experiment of recommendation performance shows that incorporating social relationship observed from user's behavior into CF is beneficial and useful to generate recommendation with 7% improvement of performance compared with benchmark methods. Finally, we confirm that interaction between users in social network is able to enhance the accuracy and give better recommendation in conventional approach.

• Asia pacific journal of information systems
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• v.23 no.3
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• pp.25-53
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• 2013

This study analyzes the effect of Computer Aided Innovation (CAI) to improve R&D Capabilities empirically. Survey was distributed by e-mail and Google Docs, targeting CTO of 235 SMEs. 142 surveys were returned back (rate of return 60.4%) from companies. Survey results from 119 companies (83.8%) which are effective samples except no-response, insincere response, estimated value, etc. were used for statistics analysis. Companies with less than 50billion KRW sales of entire researched companies occupy 76.5% in terms of sample traits. Companies with less than 300 employees occupy 83.2%. In terms of the type of company business Partners (called 'partners with big companies' hereunder) who work with big companies for business occupy 68.1%. SMEs based on their own business (called 'independent small companies') appear to occupy 31.9%. The present status of holding IT system according to traits of company business was classified into partners with big companies versus independent SMEs. The present status of ERP is 18.5% to 34.5%. QMS is 11.8% to 9.2%. And PLM (Product Life-cycle Management) is 6.7% to 2.5%. The holding of 3D CAD is 47.1% to 21%. IT system-holding and its application of independent SMEs seemed very vulnerable, compared with partner companies of big companies. This study is comprised of IT infra and IT Utilization as CAI capacity factors which are independent variables. factors of R&D capabilities which are independent variables are organization capability, process capability, HR capability, technology-accumulating capability, and internal/external collaboration capability. The highest average value of variables was 4.24 in organization capability 2. The lowest average value was 3.01 in IT infra which makes users access to data and information in other areas and use them with ease when required during new product development. It seems that the inferior environment of IT infra of general SMEs is reflected in CAI itself. In order to review the validity used to measure variables, Factors have been analyzed. 7 factors which have over 1.0 pure value of their dependent and independent variables were extracted. These factors appear to explain 71.167% in total of total variances. From the result of factor analysis about measurable variables in this study, reliability of each item was checked by Cronbach's Alpha coefficient. All measurable factors at least over 0.611 seemed to acquire reliability. Next, correlation has been done to explain certain phenomenon by correlation analysis between variables. As R&D capabilities factors which are arranged as dependent variables, organization capability, process capability, HR capability, technology-accumulating capability, and internal/external collaboration capability turned out that they acquire significant correlation at 99% reliability level in all variables of IT infra and IT Utilization which are independent variables. In addition, correlation coefficient between each factor is less than 0.8, which proves that the validity of this study judgement has been acquired. The pair with the highest coefficient had 0.628 for IT utilization and technology-accumulating capability. Regression model which can estimate independent variables was used in this study under the hypothesis that there is linear relation between independent variables and dependent variables so as to identify CAI capability's impact factors on R&D. The total explanations of IT infra among CAI capability for independent variables such as organization capability, process capability, human resources capability, technology-accumulating capability, and collaboration capability are 10.3%, 7%, 11.9%, 30.9%, and 10.5% respectively. IT Utilization exposes comprehensively low explanatory capability with 12.4%, 5.9%, 11.1%, 38.9%, and 13.4% for organization capability, process capability, human resources capability, technology-accumulating capability, and collaboration capability respectively. However, both factors of independent variables expose very high explanatory capability relatively for technology-accumulating capability among independent variable. Regression formula which is comprised of independent variables and dependent variables are all significant (P<0.005). The suitability of regression model seems high. When the results of test for dependent variables and independent variables are estimated, the hypothesis of 10 different factors appeared all significant in regression analysis model coefficient (P<0.01) which is estimated to affect in the hypothesis. As a result of liner regression analysis between two independent variables drawn by influence factor analysis for R&D capability and R&D capability. IT infra and IT Utilization which are CAI capability factors has positive correlation to organization capability, process capability, human resources capability, technology-accumulating capability, and collaboration capability with inside and outside which are dependent variables, R&D capability factors. It was identified as a significant factor which affects R&D capability. However, considering adjustable variables, a big gap is found, compared to entire company. First of all, in case of partner companies with big companies, in IT infra as CAI capability, organization capability, process capability, human resources capability, and technology capability out of R&D capacities seems to have positive correlation. However, collaboration capability appeared insignificance. IT utilization which is a CAI capability factor seemed to have positive relation to organization capability, process capability, human resources capability, and internal/external collaboration capability just as those of entire companies. Next, by analyzing independent types of SMEs as an adjustable variable, very different results were found from those of entire companies or partner companies with big companies. First of all, all factors in IT infra except technology-accumulating capability were rejected. IT utilization was rejected except technology-accumulating capability and collaboration capability. Comprehending the above adjustable variables, the following results were drawn in this study. First, in case of big companies or partner companies with big companies, IT infra and IT utilization affect improving R&D Capabilities positively. It was because most of big companies encourage innovation by using IT utilization and IT infra building over certain level to their partner companies. Second, in all companies, IT infra and IT utilization as CAI capability affect improving technology-accumulating capability positively at least as R&D capability factor. The most of factor explanation is low at around 10%. However, technology-accumulating capability is rather high around 25.6% to 38.4%. It was found that CAI capability contributes to technology-accumulating capability highly. Companies shouldn't consider IT infra and IT utilization as a simple product developing tool in R&D section. However, they have to consider to use them as a management innovating strategy tool which proceeds entire-company management innovation centered in new product development. Not only the improvement of technology-accumulating capability in department of R&D. Centered in new product development, it has to be used as original management innovative strategy which proceeds entire company management innovation. It suggests that it can be a method to improve technology-accumulating capability in R&D section and Dynamic capability to acquire sustainable competitive advantage.

• Journal of Community Nutrition
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• v.5 no.1
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• pp.21-28
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• 2003

A study was conducted to investigate the anthropometric indices, fat distribution, eating habits and levels of daily physical activity based on the body mass index (BMI ; kg/㎡) of 180 female college students. This stady was based on survey 2001 using a questionnaire. The results are as follow ; The mean age, height, weight and BMI were 20.41 ${\pm}$ 1.82 years, 161.86 ${\pm}$ 4.51cm, 53.49 ${\pm}$ 7.02kg, and 20.43 ${\pm}$ 2.65kg/㎡, respectively. The group with BMI of under 20 (the lean group) comprised 48.9% : the group with BMI of 20 to 25 (the normal group) comprised 44.4% and the group with BMI of over 25 (the obese group) comprised 6.7% of the subjects. Even though the lean and the normal groups were determined according to BMI. 12.5% of the lean group and 31.3% of the normal group had more than 25% body fat. Of the students, 11.5% of the lean group, 25.0% of the normal group and 58.3% of the obese group had of more than 0.8 waist/Hip Ratio (WHR). The medical problems suffered by the subjects were constipation (24.4%), gastroenteritis (20.6%), anemia(15.0%) and edema(13.3%), which was a result of their eating habits. Out of all the subjects, 27.2% ingested their meals irregularly, 74.4% skipped breakfast, and 92.4% of the lean group, 89.2% of the normal group and 81.8% of the obese group ingested snacks on a daily basis. Their favorite types of snacks were cookies breads and cakes (33.7%), spicy sliced rice cakes pork sausage and boiled fish cakes (18.5%), fruits (15.2%), juices and sodas (13.5%) and hamburgers and pizzas (3.9%). Their consumption of high calorie and processed foods was high, Of the subjects, 38.9% ate out daily. 45.1% had tried weight loss. Those with large upper bodies comprised 11.5%, large intermediate bodies 18.5% and large lower bodies 69.0%. Most of the students were dissatisfied with their body snaps. Of the subjects, 95.1% exercised irregularly. Daily physical activity tended to increase significantly with an increase in BMI : the lean group's average energy consumption was 1509.40㎉ the normal group's was 1792.21㎉ and the obese group's was 2334.63㎉, which were below the recommended value. This study suggests that the maintenance of an ideal weight, the improvement of eating habits and adequate exercise are needed for female college students to improve their health and nutritional status. (J Community Nutrition 5(1) 21∼28, 2003)

• Bioinformatics and Biosystems
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• v.1 no.2
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• pp.109-114
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• 2006

In proteomics research, proteins are digested into peptides by an enzyme and in mass spectrometer, these peptides break into fragment ions to generate tandem mass spectra. The tandem mass spectral data obtained from the mass spectrometer consists of the molecular weights of the precursor ion and fragment ions. The precursor ion mass of tandem mass spectrum is the first value that is fetched to sort the candidate peptides in the database search. We look far the peptide sequences whose molecular weight matches with precursor ion mass of the mass spectrum. Then, we choose one peptide sequence that shows the best match with fragment ions information. The precursor ion mass of the tandem mass spectrum is compared with that of the digested peptides of protein database within the mass tolerance that is assigned by users according to the mass spectrometer accuracy. In this study, we used reversed sequence database method to analyze the molecular weight distribution of precursor ions of the tandem mass spectra obtained by the FT LTQ mass spectrometer for human plasma sample. By reinterpreting the precursor ion mass distribution, we could compute the experimental accuracy and we suggested a method to improve the protein identification performance.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.1
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• pp.96-101
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• 2005

There were two trials involved in the experiment. Trial 1: the trial was conducted on two Taiwan Sugar Corporation (TSC) pig farms. One was located in the north of Taiwan and the other was located in the south. Both farms had wet pad and forced ventilation (WPFV) and conventional open design (COD) boar and sow houses. There were 12 Duroc boars, age ranging from 12-24 months. Half of them (6 boars) were raised in a WPFV pig house, and the other half were kept in a COD house. Semen was collected at 5-day intervals from May $1^{st}$ to the end of October. Sixteen sows (2-8 parity) were served by artificial insemination each week from the beginning of May to the end of Oct. These sows were checked for heat from 18 days to 25 days after insemination. Trial 2: there were four MPFV boar houses involved in the test. Two houses were located in the north of Taiwan, and the other two houses were located in the south. The test was conducted from January 2000 to December 2001. The total number of serviced sows by MPFV-housed boars was 35,105 head and for COD-housed boars 103,065 head. The results showed that the total semen volume, density of sperm, total sperm per ejaculate, sperm motility and morphological abnormality were significantly better (p<0.01) for boar raised in WPFV house than for COD houses. Average sperm motility in June and July was lower than for the other months. Morphological abnormality was higher during May, June and July. Although the results did not reach a significant level, the average value showed that the total volume of boar semen was higher in the north than for the south. The total semen volume production of boar raised in WPFV was higher than for boars raised in COD house, reaching a significant level only in summer. Boars kept in WPFV house had higher total sperm number than boars kept in COD house, reaching a significant level in spring (p<0.05), summer (p<0.01), and fall (p<0.05) but not in winter (p>0.05). Boars raised in WPFV house had significantly higher sperm motility than boars in COD house during spring (p<0.001), summer (p<0.001), fall (p<0.01) and winter (p<0.05). The average farrowing rate and piglets born alive were higher for boars in WPFV house than for boars in COD house, but neither reached a significant level (p>0.05). The present experiment shows that WPFV house can improve the reproduction performance of boars.

• Clinical and Experimental Pediatrics
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• v.48 no.3
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• pp.327-332
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• 2005

Interstitial lung disease refers to a group of pulmonary disorders characterized by inflammation of the interstitium, derangements and loss of alveolar capillary units leading to disruption of alveolar gas exchange, which induces symptoms of restrictive lung disease. Cases of interstitial pneumonia in children are uncommon and mostly have unknown causes. We have experienced an 8-year old boy who had symptoms of cyanosis, dry cough, dyspnea and abrupt weight loss. He had not been exposed to organic dusts, allergens or any other systemic disease infections. Chest radiology showed diffuse ground glass opacity in both lung fields. High resolution computed tomography(HRCT) showed multiple small patchy areas of consolidation with an underlying ground glass appearance in both lungs. The pathologic findings of lung biopsy tissue showed patchy areas of interstitial fibrosis, alveolar obliteration and nodular fibrotic areas, strongly suggesting interstitial pneumonia. No specific finding of viral inclusion or any other evidence of infection was found under electromicroscopy. We used peak flow meters to compare functional improvement. Forced expiratory volume in one second ($FEV_1$) was decreased to 25 percent of predicted value. The boy was given treatment with prednisone and showed improvements in HRCT findings after two months. He was able to tolerate easy exercise in school and showed clinical improvements after one year of follow up.

• Journal of Oral Medicine and Pain
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• v.23 no.4
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• pp.419-432
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• 1998

The purpose of this Study was to examine the efficacy and compliance of a mandibular advancement device(MAD) according to the severity of sleep apnea in the snorers and obstructive sleep apnea patients. Fifty-four patients (45 males, 9 females, aged 20 - 68years ) who visited Seoul National Uiversity Dental Hospital(SNUDH) to seek for the treatment of snoring and sleep apnea were classified into four groups according to the results of the nocturnal polysomnography and they were instructed to wear MAD regularly which was designed to increase the size of the upper airway by advancing the mandible. The evaluation of the efficacy and compliance of the MAD according to the severity of apnea and the duration after the usage of MAD ( 1week, 1month, 3months, 6months, 12months) was made by using quesionnaires mad in Department of Oral Medicine and Oral diagnosis, SNUDH. The obtained results were as follows : 1. All subjects results were habitual snoreres and 43 patients(79.6%) complained the loudness of snoring that can be heard out of the room. 2. Apnea index(AI) of the total subjects was mean 29.4$\pm$26.9 and respiratory disturbance index(RDI)was mean 37.6$\pm$28.0. And there was nodifference in the efficacy and the compliances of MAD according to the severity of apnea. 3. The severityi of apnea by the questionnaires significantly corresponded with the results of nocturnal polysomnography, and this fact potentiated the diagnostic value of the questionnaire. 4. after the usage of MAD, there was significant improvement in the frequency of snoring, the loudness of snoring, frequency of apnea, daytime sleepiness nad the refreshment after sleep(p<0.001) regardless of the apnea index(AI) and respiratory distrubance index(RDI). 5. The degree of the satisfaction with MAD was mean 74.4$\pm$18.4% and that of the discomfort with the MAD was 31.4$\pm$19.6%. But there was no serious complication in occlusion and temporomandibular joint with the usage of MAD and the duration of the discomfort was mean 3.3$\pm$2.2 weeks. 6. Forty-one patients(75.9%) continued the usage of MAD but thirteen patients(24.1%) stopped the use of MAD because of the discomforts and insufficient results with it.