• Journal of Intelligence and Information Systems
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• v.17 no.4
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• pp.305-316
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• 2011

Recommender system is the system which, by using automated information filtering technology, recommends products or services to the customers who are likely to be interested in. Those systems are widely used in many different Web retailers such as Amazon.com, Netfix.com, and CDNow.com. Various recommender systems have been developed. Among them, Collaborative Filtering (CF) has been known as the most successful and commonly used approach. CF identifies customers whose tastes are similar to those of a given customer, and recommends items those customers have liked in the past. Numerous CF algorithms have been developed to increase the performance of recommender systems. However, the relative performances of CF algorithms are known to be domain and data dependent. It is very time-consuming and expensive to implement and launce a CF recommender system, and also the system unsuited for the given domain provides customers with poor quality recommendations that make them easily annoyed. Therefore, predicting in advance whether the performance of CF recommender system is acceptable or not is practically important and needed. In this study, we propose a decision making guideline which helps decide whether CF is adoptable for a given application with certain transaction data characteristics. Several previous studies reported that sparsity, gray sheep, cold-start, coverage, and serendipity could affect the performance of CF, but the theoretical and empirical justification of such factors is lacking. Recently there are many studies paying attention to Social Network Analysis (SNA) as a method to analyze social relationships among people. SNA is a method to measure and visualize the linkage structure and status focusing on interaction among objects within communication group. CF analyzes the similarity among previous ratings or purchases of each customer, finds the relationships among the customers who have similarities, and then uses the relationships for recommendations. Thus CF can be modeled as a social network in which customers are nodes and purchase relationships between customers are links. Under the assumption that SNA could facilitate an exploration of the topological properties of the network structure that are implicit in transaction data for CF recommendations, we focus on density, clustering coefficient, and centralization which are ones of the most commonly used measures to capture topological properties of the social network structure. While network density, expressed as a proportion of the maximum possible number of links, captures the density of the whole network, the clustering coefficient captures the degree to which the overall network contains localized pockets of dense connectivity. Centralization reflects the extent to which connections are concentrated in a small number of nodes rather than distributed equally among all nodes. We explore how these SNA measures affect the performance of CF performance and how they interact to each other. Our experiments used sales transaction data from H department store, one of the well?known department stores in Korea. Total 396 data set were sampled to construct various types of social networks. The dependant variable measuring process consists of three steps; analysis of customer similarities, construction of a social network, and analysis of social network patterns. We used UCINET 6.0 for SNA. The experiments conducted the 3-way ANOVA which employs three SNA measures as dependant variables, and the recommendation accuracy measured by F1-measure as an independent variable. The experiments report that 1) each of three SNA measures affects the recommendation accuracy, 2) the density's effect to the performance overrides those of clustering coefficient and centralization (i.e., CF adoption is not a good decision if the density is low), and 3) however though the density is low, the performance of CF is comparatively good when the clustering coefficient is low. We expect that these experiment results help firms decide whether CF recommender system is adoptable for their business domain with certain transaction data characteristics.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.3
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• pp.311-317
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• 2007

The purpose of this study is to evaluate the nutrient intake and selected blood parameters of adults with metabolic syndrome (MS) and to provide data in forming a dietary guideline for the prevention of chronic diseases. Subjects were recruited and divided into two groups according to the NCEP-ATP III criteria and WHO Asia-Pacific Area criteria for obesity. MS group was defined as subjects who have three or more risk factors and control group was defined as those with two or less of the risk factors. The average age, height, weight, body mass index (BMI) were 58.8 years, 158.0 cm, 66.3 kg, $26.5\;kg/m^{2}$, respectively, in the MS group; and 58.4 years, 158.9 cm, 59.6 kg, $23.5\;kg/m^{2}$, respectively, in the control group. The weight and BMI in the MS group were significantly higher than those in the control (p<0.001). There was no significant difference in the food and nutrient intake between the MS and control group. Male subjects in the MS group showed significantly higher intake of mushrooms than those in the control (p<0.05). Egg consumption in the MS group was significantly lower than those in the control (p<0.01). Consumption of vegetables and fiber was significantly lower for female subjects in the MS group than those in the control (p<0.05). Serum GPT, AI and WBC count in the MS group (27.8 IU/L, 3.7, $5964.2\;{\mu}/L$) were significantly higher than those in the control (22.6 IU/L, 3.2, $5250.0\;{\mu}/L$; p<0.01, p<0.001, p<0.01). In conclusion, consuming fiber and vegetables may prevent and reduce metabolic syndrome in adult men and women, and this study demonstrates the need for proper dietary management for them.

• Journal of Korean Academy of Nursing
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• v.18 no.2
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• pp.162-188
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• 1988

The purpose of this study is to guide the direction of the Korean nursing education to analysize ⑴ the philosophy and objectives ⑵ curriculum, and ⑶ educational environment. This analysis is based on the data from 50 nursing schools (14 4-year colleges and 35 3-year colleges) The survey was conducted from Dec. 1986 through Jan. 1987 by mail. 1) Educational philosophy and objectives 10 4-year colleges and 8 3-year college program have curricular philosoph. Most popular curricular philosophies are human beings, health, nursing, nursology, nursing education, nurses role in the present and in the future. 10 nursing schools mentioned that human being is the subject to interact with : environment physically, mentally and socially. 2 schools mentioned that health is the state of functioning well physically, mentally and socially. 13 schools mentioned that the nursing is the dynamic act to maintain and to promote the highest possible level of health. 4 schools mentioned that the nursology is an applied science. 4 schools mentioned that nursing education is the process to induce the behavioural changes based on the individual ability. There is different opinion about the nurses' role between 4-year college and 3-year college. In the responses from 4-year colleges they focus on the leadership in effective changes, self-regulating and self-determining responsibilities, applying the new technology, continuing education, and participation in research to further nursing knowledge. In the responses from 3-year colleges, they focus on the education in college, primary health care nursing, direct care provider and public health education. Among 50 respondents 40 schools have educational goals which can be divided into two categories. One is to establish the moral and the other is to develop the professionalism. 2) Curriculm The analsis of curriculum is only based on the data from the 4-year colleges because the most of 3-year colleges follow the curriculum guideline set by the Ministry of Education. a) Comparison of the credits in cultural subject and in nursing major. The average required credit for graduation is 154.6 and the median credit is the range of 140-149. The average credit of cultural subjects is 43.4. In detail, the average number of credit of required course and elective courses are 24.1 and 19.3 respectively. The average credit for major subject is 111.2. In detail, the average credit for required courses and electives course are 100.9 and 10.4 respectively. In 5 colleges, students are offered even on elective course b) Comparison of the credit by class. The average earned credits are as follows : 41.1 in freshman, 400 in sophormore 38.3 in junior and 32.4 in senior. Cultural subjects are studied in early phases. c) Comparison of the compulsory and elective cultural subject by institute. The range of credit is 7-43 in compulsory cultural subjects and there are lot of differences among institutions. While all respondents require liberal arts as compulsary subjects, few respondents lists social science, natural science and behavioral science as required subjects. Social science-related subjects are frequently chosen as cultural subjects d) Distribution of creditsin cultural subjects by institute. The liberal art subjects are taught in 20 institute. English and physical education courses are taught in all instituions. The social science subjects are taught in 15 colleges and the basic Psycology and the Basic sociology are the most popular subjects. The natural science subjects are taught in 7 colleges and Biology and Chemistry are the most popular subjects among them. e) Distribution of credits in major basic courses by institute. Most of the institutes select Anatomy, Microbiology, Physiology, biochemistry and Pathology as basic major courses. f) Comparison of the required and elective courses for nursing major by institutions. Subjects and credit ranges in major are varing by institute. More than half of the respondents select the following subjects as required major subjects. (1) Adults Health Nursing and Practice (19.5 credits) (2) Mother and Child Care and Practice (8.9 credits) (3) Community Health Care and Practice (8.5 credits) (4) Psychiatric Nursing Care and Practice (8.1 credits) (5) Nursing Management and Practice (3.9 credits) (6) Fundamental of Nursing, Nursing Research and Health Assessment and Practice. Three institutions select Introduction to nursing, Rehabilitation Nursing, School Nursing, Public Health Nursing, Nursing English, Communication, Human Development as electives in nursing major. 3) Educational environment a) Nursing institution There are forty-three 3-year colleges and seventeen 4-year colleges and 81.4% of which are private b) Number of students and faculty 19.2% of the students are in 4-year colleges and 80.8% of the students are in 3-year colleges. In 4-year colleges, the number of nursing faculty members is in the other of assistant professor, instructor and professor. In 3-year colleges, the orderiis lecturer, associate professor, full time instructor and assistant professor. In 4-year colleges, 18.8 students are allocated per nursing faculty and in 3-year colleges, 33.1 students are allocated per nursing faculty. c) Clinical practices 66.7% of the 4-year colleges practice over 1201 hours in clinic and 28.5% of 3-year colleges practice over 1201 hours in clinic. In 4-year colleges, 11.5 students are allocated per nursing faculty and in 3-year colleges,17 students are allocated per nursing faculty The survey shows no difference in the procedure between 4-year colleges and 3-year colleges but 3-year colleges choose the more variety practicing site such as special hospital and community health clinic. d) Audiovisual facilities The survey shows a lot of difference in audiovisual facilities among institution and 3-year colleges are less equipped than 4-year colleges.

• Korean Security Journal
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• no.19
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• pp.105-138
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• 2009

This study's purpose is to present the improvement of effectiveness of security activity for international conference among Several Countries which can be held hereafter. On the basis of security activity problems originating in APEC that had been held in Busan in 2005. I made up questions three times to on the members of the police, military, fire figher and national intelligence service who had experienced in Busan APEC and recognition of possible problem and possibility of improvement on each item of questions was analyzed by Delphi Method. Also interviews with 4 security experts selected from each security agency were conducted to present improvement in each part of problem. The results obtained from the face to face interview with four experts of security-enforcement agency about the role and importance of site activity stage for international conference among several countries are as followings ; First, the system that experienced security-enforcement agents can be selected for the next national security event is needed, by data-basing the security-enforcement agents who were experienced in security event as man power management. Second, the middle-term plan for the introduction of high-tech equipment and joint inspection with relevant security agents are needed for the efficient explosive technical detection. Third, high-tech security equipment could be introduced through the international high-tech security equipment exhibition. Fourth, an anti-terrorism plan should be measured by sharing information through the cooperation with domestic and international intelligence agency. Fifth, public relations should be measured systematically by organization rather than agents' individual public relations. Sixth, political consideration to secure integrative coordination with other agency is needed for security activity, through normal cooperation with fire fighting related agency such as an electric, gas, elevator company. Seventh, a definite press guideline is needed for a convenient news coverage and safety during security event.

• Journal of agricultural medicine and community health
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• v.28 no.2
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• pp.1-14
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• 2003

Objectives: This paper introduces need and supply level of rural mental health care service and especially focuses on the evaluation for the community mental health programs of Public Health Centers(PHCs) in rural areas as the facilities for primary mental health care. Methods: We defined the need as prevalance rate and service utilization rate, for which reviewed the results of the epidemiological study of mental disorders using Korean Composite International Diagnostic Interview surveyed on a nationwide scale in 2001. Supply was appraised in terms of psychiatric beds and primary mental heath care facilities such as private psychiatric clinics, facilities for social rehabilitation, PHCs running community mental health programs. For this, we reveiwed a variety of annual reports related mental health published by Ministry of Health and Welfare. To evaluate the community mental health programs of PHCs in rural areas, we selected. randomly samples out of the 3rd community health plans including the contents of community mental health programs, which submitted by 89 rural counties and 44 cities mixed with rural areas, and used the program's guideline established by central government as a standard. Results: Prevalence rates of major psychiatric diseases such as schizophrenia, alcoholism, major depression, anxiety disorder were higher in rural area than in urban area and 8.9% of psychiatric patients in both areas stayed at homes contacted with mental health manpower more than one time during the last year. Psychiatric beds were sufficiently supplied, but urban area had less beds than rural area contrary to general health care service. Psychiatric clinics were supplied very insufficiently in rural areas and PHCs bridged the gap instead. However rural PHCs got less financial support for community mental health programs from higher positioned agencies than urban PHCs. Rural community health programs not supported hardly worked out. Conclusions: Central government should consider a special policy for rural primary mental health care, because private psychiatric clinics can't be introduced in rural areas due to demand-deficiency and the financial independence of rural counties was very vulnerable.

• Journal of Food Hygiene and Safety
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• v.30 no.2
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• pp.132-142
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• 2015

The purpose of this study was to investigate the perception and information needs about food additives from the parents of elementary school children, and to develop a smartphone application (App) providing information about food additives, and finally to assess its educational effects. A survey was conducted in April 2013 by using a self-administered questionnaire, and total 358 responses were collected from the parents living in Seoul and Gyeonggi province. While purchasing processed foods, parents considered safety (40.5%) as the most important factor, and first checking item except production and expiration dates was origin labelling (35.4%), and chose foods with less food additives (63.1%). Parents recognized food additives as the most dangerous (42.7%), and 75.1% responded the level of danger as 'very dangerous'. However, 82.4% of parents didn't have experiences to get educations about food additives. Based on their information needs including the safety, legal standards and the foods containing food additives. a smartphone App designated as 'Catch up Food Additives' consisting of the definition, safety, food labelling guideline, management, animation about food additives was developed. When the App was exposed to the parents (n = 27), their negative perceptions on food additives were improved significantly. These results showed that providing information and education about food additives using smartphone App was very fast and effective for the promotion of risk communication on food additives with the parents.

• Korean Journal of Ecology and Environment
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• v.41 no.2
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• pp.216-227
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• 2008

To understand eutrophication in the upper regions of brackish Lake Sihwa with a limited water exchange, temporal and spatial distributions of pollutants in water and sediment were investigated from March to October in 2005 and 2006. Also, pollution levels of water and sediment were estimated by trophic state index (TSI) and sediment quality guideline (SQG). Total nitrogen (TN), total phosphorus (TP), organic matter (COD), and chlorophyll $\alpha$ (Chl-$\alpha$) concentrations in the surface waters were largely varied temporally and spatially, and the variations were highest in the middle areas where strong halocline was formed. Chl-$\alpha$ concentrations in the middle area were very high in April (>$900\;{\mu}g\;L^{-1}$) when algal blooms (red tides) occurred. The relationships between TN and Chl-$\alpha$ (r=0.31), and TP and Chl-$\alpha$ (r=0.65) indicated that the algal growth was primarily affected by phosphorus rather than nitrogen. The distribution of COD was similar to that of Chl-$\alpha$, indicating that the autochthonous organic matters may be a more important carbon source, especially in the middle areas. The brackish water regions were classified as eutrophic or hypertrophic based on their TSI values ($69{\sim}76$). In addition, the content of nutrients (especially TP) in surface sediments were classified as severe polluted state, except the upper areas. Major causes of the eutrophication observed were probably due to high nutrients loading from watersheds, the phosphorus release from anaerobic sediment, and long retention time by the limited water exchange through the sluice gates.