• Journal of Intelligence and Information Systems
• /
• v.23 no.2
• /
• pp.19-38
• /
• 2017

Collaborative filtering (CF) algorithm has been popularly used for implementing recommender systems. Until now, there have been many prior studies to improve the accuracy of CF. Among them, some recent studies adopt 'hybrid recommendation approach', which enhances the performance of conventional CF by using additional information. In this research, we propose a new hybrid recommender system which fuses CF and the results from the social network analysis on trust and distrust relationship networks among users to enhance prediction accuracy. The proposed algorithm of our study is based on memory-based CF. But, when calculating the similarity between users in CF, our proposed algorithm considers not only the correlation of the users' numeric rating patterns, but also the users' in-degree centrality values derived from trust and distrust relationship networks. In specific, it is designed to amplify the similarity between a target user and his or her neighbor when the neighbor has higher in-degree centrality in the trust relationship network. Also, it attenuates the similarity between a target user and his or her neighbor when the neighbor has higher in-degree centrality in the distrust relationship network. Our proposed algorithm considers four (4) types of user relationships - direct trust, indirect trust, direct distrust, and indirect distrust - in total. And, it uses four adjusting coefficients, which adjusts the level of amplification / attenuation for in-degree centrality values derived from direct / indirect trust and distrust relationship networks. To determine optimal adjusting coefficients, genetic algorithms (GA) has been adopted. Under this background, we named our proposed algorithm as SNACF-GA (Social Network Analysis - based CF using GA). To validate the performance of the SNACF-GA, we used a real-world data set which is called 'Extended Epinions dataset' provided by 'trustlet.org'. It is the data set contains user responses (rating scores and reviews) after purchasing specific items (e.g. car, movie, music, book) as well as trust / distrust relationship information indicating whom to trust or distrust between users. The experimental system was basically developed using Microsoft Visual Basic for Applications (VBA), but we also used UCINET 6 for calculating the in-degree centrality of trust / distrust relationship networks. In addition, we used Palisade Software's Evolver, which is a commercial software implements genetic algorithm. To examine the effectiveness of our proposed system more precisely, we adopted two comparison models. The first comparison model is conventional CF. It only uses users' explicit numeric ratings when calculating the similarities between users. That is, it does not consider trust / distrust relationship between users at all. The second comparison model is SNACF (Social Network Analysis - based CF). SNACF differs from the proposed algorithm SNACF-GA in that it considers only direct trust / distrust relationships. It also does not use GA optimization. The performances of the proposed algorithm and comparison models were evaluated by using average MAE (mean absolute error). Experimental result showed that the optimal adjusting coefficients for direct trust, indirect trust, direct distrust, indirect distrust were 0, 1.4287, 1.5, 0.4615 each. This implies that distrust relationships between users are more important than trust ones in recommender systems. From the perspective of recommendation accuracy, SNACF-GA (Avg. MAE = 0.111943), the proposed algorithm which reflects both direct and indirect trust / distrust relationships information, was found to greatly outperform a conventional CF (Avg. MAE = 0.112638). Also, the algorithm showed better recommendation accuracy than the SNACF (Avg. MAE = 0.112209). To confirm whether these differences are statistically significant or not, we applied paired samples t-test. The results from the paired samples t-test presented that the difference between SNACF-GA and conventional CF was statistical significant at the 1% significance level, and the difference between SNACF-GA and SNACF was statistical significant at the 5%. Our study found that the trust/distrust relationship can be important information for improving performance of recommendation algorithms. Especially, distrust relationship information was found to have a greater impact on the performance improvement of CF. This implies that we need to have more attention on distrust (negative) relationships rather than trust (positive) ones when tracking and managing social relationships between users.

• Sleep Medicine and Psychophysiology
• /
• v.24 no.1
• /
• pp.46-54
• /
• 2017

Objectives: Domestic violence is related to many psychiatric diseases, such as depression, anxiety disorder, and PTSD. Heart rate variability (HRV) is an index of autonomic control of the heart and is related to cardiovascular and emotional disorders. Although there have been some studies on the effects of domestic violence on women's mental health, relatively little information is available on HRV in this population. The aim of this study is to investigate demographic data, psychological features, and HRV in female victims of domestic violence and difference between Korean and foreign female victims. Methods: A total of 210 female victims of domestic violence (166 Korean women and 44 foreign women) were recruited for this study. Psychological symptoms were measured using the Hamilton Rating Scale for Anxiety (HAM-A), Hamilton Rating Scale for Depression (HAM-D), and Impact of Event Scale-Revised (IES-R). HRV measures were assessed by time-domain and frequency-domain analyses. Results: The mean score of HAM-A was 13.81, that of HAM-D was 12.92, and that of IES-R was 33.61 ; there were no significant differences between Korean and foreign women in these measures. In HRV time domain analyses, approximate entropy (ApEn) was significantly increased in foreign women compared to the Korean women. The square root of the mean of the sum of the squares of differences between adjacent NN intervals (RMSSD) was significantly decreased in foreign women compared to Korean women. There were no significant differences in the other HRV variables between Korean and foreign women. Conclusion: Female victims of domestic violence in Korea are associated with depression, anxiety, and PTSD symptoms. The physiologic factors of a female victim's nationality could be related to higher ApEn and lower RMSSD in foreign female victims. These findings have important implications for future study to study the relationships among ethnic and environmental factors and HRV variables.

• Korean Journal of Psychosomatic Medicine
• /
• v.26 no.1
• /
• pp.35-43
• /
• 2018

Objectives : Effects of multiple trauma are complex and extend beyond core PTSD symptoms. However, few psychological instruments for trauma assessment address this issue of symptom complexity. The Trauma Symptom Checklist-40 (TSC-40) is a self-report scale that assesses wide range of symptoms associated with childhood or adult traumatic experience. The purpose of the present study was to evaluate the validity of the Korean Version of the TSC-40 in a sample of psychiatric outpatients. Methods : Data of 367 treatment-seeking patients with DSM-IV diagnoses were obtained from an outpatient department of psychiatric unit at a university hospital. The diagnoses were anxiety disorder, posttraumatic stress disorder, depressive disorder, adjustment disorder and others. Included in the psychometric data were the TSC-40, the Life events checklist, the Impact of Event Scale-Revised, the Zung's Self-report Depression Scale, and the Zung's Self-report Anxiety Scale. Cronbach's ${\alpha}$ for internal consistency were calculated. Convergent and concurrent validity was approached with correlation between the TSC-40 and other scales (PTSD, anxiety and depression). Results : Exploratory factor analysis of the Korean Version of TSC-40 extracted seven-factor structure accounted for 59.55% of total variance that was contextually similar to a six-factor structure and five-factor structure of the original English version. The Korean Version of TSC-40 demonstrated a high level of internal consistency. (Cronbach's ${\alpha}=0.94$) and good concurrent and convergent validity with another PTSD scale and anxiety and depression scales. Conclusions : Excellent construct validity of The Korean Version of TSC-40 was proved in this study. And subtle difference in the factor structure may reflect the cultural issues and the sample characteristics such as heterogeneous clinical population (including non-trauma related disorders) and outpatient status. Overall, this study demonstrated that the Korean version of TSC-40 is psychometrically sound and can be used for Korean clinical population.

• Korean Journal of Psychosomatic Medicine
• /
• v.18 no.2
• /
• pp.82-93
• /
• 2010

Objectives : The purpose of this study was to explore attitude and belief about menopause and severity of menopausal symptoms according to menopausal status. This study conducted a cross-sectional assessment of the effects of depressive symptoms and the severity of trait anxiety on the severity of menopausal symptoms. Methods : Participants were all outpatients at the psychiatric outpatient clinic of Korea University Guro Hospital. All participants, aged 40 to 64, had depressive or anxiety disorders and were divided into the premenopause, perimenopause, premenopause, and postmenopause groups. Menopause Rating Scale(MRS) was used to measure the severity of menopausal symptoms. The attitude toward menopause was examined by a self-report questionnaire regarding menopause. Beck Depression Inventory(BDI) and State-Trait Anxiety Inventory(STAI) were used to assess depressive symptoms and anxiety. Results : The severity of menopausal symptoms was not different among the groups according to menopausal status. There was a significant correlation between a negative attitude toward menopause and the severity of menopausal symptoms. Patients with moderate to severe depressive symptoms and trait anxiety had more severe menopausal symptoms. Conclusion : Negative attitude toward menopause, depressive symptoms, and anxiety had a significantly negative impact on the severity of menopausal symptoms. The results of this study suggest that treatment to relieve depressive symptoms and anxiety and intervention to reduce negative attitude toward menopause are required. Further studies with larger sample size are needed to evaluate potentially effects of depressive symptoms and anxiety on severity of menopausal symptoms in middle-aged female psychiatric patients.

• Journal of Oral Medicine and Pain
• /
• v.37 no.4
• /
• pp.195-203
• /
• 2012

Recurrent aphthous ulcer(RAU) is the most frequent form of oral ulceration with a prevalence in the general population ranging between 5% and 60%. The peak age of onset is between 10 and 19 years of age, and it can persist into adulthood and throughout the patient's lifespan, with no gender predilection. The disease is characterized clinically into three types: minor aphthous ulcer, major aphthous ulcer and herpeticform ulcers. The cause of RAU is unknown and thought to be multifactorial with many triggers or precipitating factors that include familial tendency or genetic predisposition, allergy, medications, hormones, stress or anxiety, and immunologic abnormalities. The need for consideration of psychological factors in the pathogenesis of oral disease has been increasingly acknowledged over the last decades and many studies have highlighted the psycho-social impact of oral conditions. In this study, we tried to evaluate the influence of emotional stress in RAU. There were thirty patients with a clinical diagnosis of RAU and other subjects who did not show any signs of systemic disorders include RAU. They are evaluated by using modified Holmes and Rahe's Social Readjustment Rating Scale (SRRS). As a result, a significantly higher level of stress was found in the RAU patients than the control group. Therefore it can be concluded that psychological stressors play an important role in the RAU.

• Korean Journal of Psychosomatic Medicine
• /
• v.8 no.1
• /
• pp.72-87
• /
• 2000

Objectives : This study was to provide normative data of Korean version of DSI(K-DSI), a sensitive measure of relatively minor stressors that could be administered daily. Methods : K-DSI was administered in 524 adults, age of 19 or over, daily for 1 week. On the seventh day, Becks Depression Inventory(BDI), State-Trait Anxiety Inventory(STAI), and Social Readjustment Rating Scale(SRRS) were also given to test the convergent validity. Analyses(ANOVA or t-test) were conducted to examine the potential effects of demographic variables on K-DSI score. Internal consistency for reliability and Pearson's corelation coefficient with BDI, STAI, SRRS for convergent validity were computed. Percentile scores were calculated for daily and weekly K-DSI Event, Impact and I/E Ratio scores. Results : K-DSI scores in women were higher than those in men. According to age and educational level, the younger and the higher educational level the normative groups were, the higher were K-DSI scores. Among the 5 categories of the inventory, the category of cognitive stressors was highest. Internal consistency of K-DSI(Cronbach's $\alpha$) was .99. Daily and Weekly events and impacts scores were significantly correlated with the scores of State-Trait Anxiety Inventory, Social Readjustment Rating Scale, and Beck Depression Inventory. 75 percentile scores of the daily/weekly Events, Impacts, and I/E ratio were 17/118 - 124, 57/368 - 389 and 3.48 - 3.49/3.47 - 3.48 respectively. And 95 percentile scores of daily/weekly Events, Impacts, and I/E ratio were 57/151- 161, 405/1038 - 1122, and 4.72 - 4.86/4.46 - 4.56 respectively. Conclusion : Reliability and validity of K-DSI were tested satisfactorily. Authors presented the normative data of K-DSI for Koreans. K-DSI could be a useful measure in clinical settings or researches to assess the minor stressors frequently experienced in everyday life.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
• /
• v.18 no.6
• /
• pp.87-104
• /
• 2023

Recently, concerns are growing over small and medium-sized companies holding out on debt as domestic loan interest rates have risen sharply due to the prolonged impact of COVID-19 and soaring raw material prices. In addition, loans from small and medium-sized enterprises, which are difficult in the business environment, are increasingly being rejected due to high loan interest rates and excessive submission documents and financial statements-oriented screening of loans by the financial sector. Therefore, since it is necessary to discuss ways to promote financing and investment by SMEs, this study intends to suggest ways to promote investment through the use of SMEs' ESG systems. The purpose of this study is to suggest that the use of ESG evaluation indicators used as non-financial indicators helps predict the corporate value of SMEs and the importance of SMEs actively participating in ESG information disclosure. This study suggests the necessity of introducing and practicing ESG by SMEs where financing is important, and aims to analyze as an empirical result that the use of non-financial indicators helps predict corporate value. As a result of the study, the ESG performance and corporate value of SMEs showed a positive (+) relationship. It can be seen that both the grades and corporate value of SMEs by ESG sector have a positive (+) influence relationship. The total ESG rating was confirmed to have a positive effect on corporate value, and it was confirmed that SMEs with higher ESG environment, social, and governance ratings were evaluated higher. According to the research results, it is suggested that SMEs also need to use ESG evaluation indicators, and in order to promote the growth of SMEs, it is suggested that research on ways to re-examine the corporate value of SMEs is necessary. Therefore, this study suggests that the use of ESG should be actively recommended and implemented as a way to establish a management strategy for SMEs, and that efforts to disclose ESG information can soon help SMEs solve information asymmetry. In addition, SMEs want to understand the investment mechanism that the introduction and practice of ESG can lead to the improvement of the value of SMEs and suggest the necessity of SME-type ESG policies in the future.

• Journal of Korean Academy of Nursing
• /
• v.25 no.4
• /
• pp.681-695
• /
• 1995

It has been noted that a genetic alteration of cells influenced by unhealthy lifestyle In addition to a series of other carcinogens increases various neoplasmic diseases. Therefore the importance of lifestyle that minimizes such impact on health should be emphasized. Since stomach cancer, the most common neoplasmic disease in Korea, is re-lated to the Korean lifestyle and as there's a possibility of its recurrence, people with stomach cancer need to lead a healthy lifestyle. The purpose of this study is to provide a basis for nursing intervention strategies to promote health promoting behaviors that are constructive to a healthy lifestyle. A multivariate model was constructed based on the fender's health promotion model and Booker's health belief model by including influential factors such as hope. The sample was composed of 164 patients with stomach cancer who visited outpatient clinics of a university hospital in Seoul. The following instruments were used in the study after some adaptation : Wallston and others' multidimensional health locus of control scale Laffrey's health conception scale, Lawston and others' health self- rating scale, Walker and others' health promotion lifestyle profile and Rogenberg's self esteem scale. In addition Moon's health belief scale was used with some modification. For self efficacy, the present author constructed a self-efficacy scale based on previous research. The above mentioned instruments were tested in a pilot study with 24 patients with stomach cancer. The reliabilities of instruments were tested with Cronbach's alpha(0.574∼0.949). Data were analyzed using a SAS program (or Pearson correlation coefficients, descriptive correlational statistics and stepwise multiple regression. The results are as follows : 1. The scores on the health promoting behavior scale ranged from 55 to 145 with a mean of 107.91 (S. D : 16.50). The mean scores(range 1-4) on the different dimensions were nutrition 3.14, exercise 2.48, stress management 2.69, health responsibility 2.65, interpersonal relationship 2.878E self actualization 2.85. 2. There were significant correlations among all the predictive variables & the health promoting behavior (r=.20-.55, p〈.01) 3. Stepwise multiple regression analysis showed that : 1) Hope was the main predictor and accounted for 29.8％ of the total variance. 2) Self efficacy, perceived barriers & self esteem accounted for an additional 14.6% of the total variance. 3) Hope, self efficacy, perceived barriers & self esteem altogether accounted for 44.3％ of the total variance. In conclusion, hope, self efficacy, perceived barriers & self esteem were identified as important variables that contributed to promote health promoting behavior.

• Culinary science and hospitality research
• /
• v.22 no.4
• /
• pp.254-264
• /
• 2016

This research was conducted over about four weeks from May 1, 2015 until May 30. First, of the hotel restaurant visit motivations, awareness image B=0.524 (p<.001), food B=0.121 (p<.05), and distinctiveness B=0.251 (p<.001) had a significantly positive impact on consumer attitude. Second, the hotel restaurant, visit motivation and preference image B=0.577 (p<.001), Social B=0.192 (p<.001), distinctiveness B=0.173 (p<.01) was significantly positive on consumer attitudes there were influential (+). Third, there was the influence of motivation and purchases, visit the hotel restaurant between images of B=0.705 (p<.001), Around B=0.113 (p<.01) significantly positive (+) on purchase of consumer attitudes to food B=-0.135 (p<.01) and social B=-0.123 (p<.001) are part had the effect of (-). Addition, consumers also look at the attitude and awareness Revisit B=0.464 (p<.001), Rating B=0.321 (p<.001), even the purchase of B=0.205 (p<.001) all significantly positive (+) with there was influence. If the five-star hotel from carrying out marketing activities around awareness, preference, and purchase intention judges will give a great help in hotel management.

• The Journal of Internal Korean Medicine
• /
• v.41 no.4
• /
• pp.676-687
• /
• 2020

Objectives: The aim of this study was to report improvement of acute headache incurred in a traffic accident in five patients who underwent inpatient treatment with Korean medicine. Methods: We collected data for traffic accident patients with acute headache who were admitted to the Ja-Seng Hospital of Korean Medicine from November 2019 to April 2020 and received combinational Korean medical treatment. All patients had numerical rating scale (NRS) values of 6 or greater. The patients were treated with acupuncture, pharmacopuncture, herbal medicine, and chuna treatment. We measured the validity of the treatment with the NRS, Headache Impact Test-6 (HIT-6), and Henry Ford Headache Disability Inventory (HDI) at admission and on the date of hospital discharge. Results: At the end of the treatment, all patients showed decreases in NRS, HDI, and HIT scores. Conclusions: The combination of Korean medicine at admission was effective in five patients with acute headache after a traffic accident. However, the number of subjects was insufficient and individual efficacy was not measured in this study. Therefore, further studies are needed on this topic.