• Title/Summary/Keyword: Group management

Search Result 9,757, Processing Time 0.048 seconds

Predicting the Performance of Recommender Systems through Social Network Analysis and Artificial Neural Network (사회연결망분석과 인공신경망을 이용한 추천시스템 성능 예측)

  • Cho, Yoon-Ho;Kim, In-Hwan
    • Journal of Intelligence and Information Systems
    • /
    • v.16 no.4
    • /
    • pp.159-172
    • /
    • 2010
  • The recommender system is one of the possible solutions to assist customers in finding the items they would like to purchase. To date, a variety of recommendation techniques have been developed. One of the most successful recommendation techniques is Collaborative Filtering (CF) that has been used in a number of different applications such as recommending Web pages, movies, music, articles and products. 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. Broadly, there are memory-based CF algorithms, model-based CF algorithms, and hybrid CF algorithms which combine CF with content-based techniques or other recommender systems. While many researchers have focused their efforts in improving CF performance, the theoretical justification of CF algorithms is lacking. That is, we do not know many things about how CF is done. Furthermore, 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 the performances of CF algorithms in advance is practically important and needed. In this study, we propose an efficient approach to predict the performance of CF. Social Network Analysis (SNA) and Artificial Neural Network (ANN) are applied to develop our prediction model. CF can be modeled as a social network in which customers are nodes and purchase relationships between customers are links. SNA facilitates an exploration of the topological properties of the network structure that are implicit in data for CF recommendations. An ANN model is developed through an analysis of network topology, such as network density, inclusiveness, clustering coefficient, network centralization, and Krackhardt's efficiency. 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. Inclusiveness refers to the number of nodes which are included within the various connected parts of the social network. Centralization reflects the extent to which connections are concentrated in a small number of nodes rather than distributed equally among all nodes. Krackhardt's efficiency characterizes how dense the social network is beyond that barely needed to keep the social group even indirectly connected to one another. We use these social network measures as input variables of the ANN model. As an output variable, we use the recommendation accuracy measured by F1-measure. In order to evaluate the effectiveness of the ANN model, sales transaction data from H department store, one of the well-known department stores in Korea, was used. Total 396 experimental samples were gathered, and we used 40%, 40%, and 20% of them, for training, test, and validation, respectively. The 5-fold cross validation was also conducted to enhance the reliability of our experiments. The input variable measuring process consists of following three steps; analysis of customer similarities, construction of a social network, and analysis of social network patterns. We used Net Miner 3 and UCINET 6.0 for SNA, and Clementine 11.1 for ANN modeling. The experiments reported that the ANN model has 92.61% estimated accuracy and 0.0049 RMSE. Thus, we can know that our prediction model helps decide whether CF is useful for a given application with certain data characteristics.

Comparative Analysis of ViSCa Platform-based Mobile Payment Service with other Cases (스마트카드 가상화(ViSCa) 플랫폼 기반 모바일 결제 서비스 제안 및 타 사례와의 비교분석)

  • Lee, June-Yeop;Lee, Kyoung-Jun
    • Journal of Intelligence and Information Systems
    • /
    • v.20 no.2
    • /
    • pp.163-178
    • /
    • 2014
  • Following research proposes "Virtualization of Smart Cards (ViSCa)" which is a security system that aims to provide a multi-device platform for the deployment of services that require a strong security protocol, both for the access & authentication and execution of its applications and focuses on analyzing Virtualization of Smart Cards (ViSCa) platform-based mobile payment service by comparing with other similar cases. At the present day, the appearance of new ICT, the diffusion of new user devices (such as smartphones, tablet PC, and so on) and the growth of internet penetration rate are creating many world-shaking services yet in the most of these applications' private information has to be shared, which means that security breaches and illegal access to that information are real threats that have to be solved. Also mobile payment service is, one of the innovative services, has same issues which are real threats for users because mobile payment service sometimes requires user identification, an authentication procedure and confidential data sharing. Thus, an extra layer of security is needed in their communication and execution protocols. The Virtualization of Smart Cards (ViSCa), concept is a holistic approach and centralized management for a security system that pursues to provide a ubiquitous multi-device platform for the arrangement of mobile payment services that demand a powerful security protocol, both for the access & authentication and execution of its applications. In this sense, Virtualization of Smart Cards (ViSCa) offers full interoperability and full access from any user device without any loss of security. The concept prevents possible attacks by third parties, guaranteeing the confidentiality of personal data, bank accounts or private financial information. The Virtualization of Smart Cards (ViSCa) concept is split in two different phases: the execution of the user authentication protocol on the user device and the cloud architecture that executes the secure application. Thus, the secure service access is guaranteed at anytime, anywhere and through any device supporting previously required security mechanisms. The security level is improved by using virtualization technology in the cloud. This virtualization technology is used terminal virtualization to virtualize smart card hardware and thrive to manage virtualized smart cards as a whole, through mobile cloud technology in Virtualization of Smart Cards (ViSCa) platform-based mobile payment service. This entire process is referred to as Smart Card as a Service (SCaaS). Virtualization of Smart Cards (ViSCa) platform-based mobile payment service virtualizes smart card, which is used as payment mean, and loads it in to the mobile cloud. Authentication takes place through application and helps log on to mobile cloud and chooses one of virtualized smart card as a payment method. To decide the scope of the research, which is comparing Virtualization of Smart Cards (ViSCa) platform-based mobile payment service with other similar cases, we categorized the prior researches' mobile payment service groups into distinct feature and service type. Both groups store credit card's data in the mobile device and settle the payment process at the offline market. By the location where the electronic financial transaction information (data) is stored, the groups can be categorized into two main service types. First is "App Method" which loads the data in the server connected to the application. Second "Mobile Card Method" stores its data in the Integrated Circuit (IC) chip, which holds financial transaction data, which is inbuilt in the mobile device secure element (SE). Through prior researches on accept factors of mobile payment service and its market environment, we came up with six key factors of comparative analysis which are economic, generality, security, convenience(ease of use), applicability and efficiency. Within the chosen group, we compared and analyzed the selected cases and Virtualization of Smart Cards (ViSCa) platform-based mobile payment service.

H-T-P reaction Study on differences between the juvenile delinquents groups classified by the family system type for Creative happy Education management (창의적 행복학교 교육경영을 위한 HTP 검사 반응 연구)

  • Park, Soon Marn;Choi, Chong Myoung;Kim, Jin Nyo;Byun, Sang Hae
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
    • /
    • v.8 no.3
    • /
    • pp.157-163
    • /
    • 2013
  • This study is to notify differences of H-T-P reactions between Juvenile delinquents groups classified by family system type. This study aims to know reaction of 'House' on each juvenile delinquents and apply to creative school education administration. The research was performed as below: First, Measuring and descriptive statistical analysis were performed. One hundred and twenty subjects who were youths disposed of Seoul nambu youth alternative education center. Data were collected from July to October in 2012. Then There were classified Two groups following subjects; 'parents family' and 'single parent family'. Second, Questionaries assessing demographic and H-T-P by Buck, N. Third, statistical analysis was done by SPSS for Window 18.0. To Verify the reliability of the measures and correlations between two groups, and to find out the difference of the reaction of 'House', were used frequency analysis and Pearson Chi-Square. The results of this is significant personality types of juvenile delinquents are followings; The Juvenile delinquents living 'Single parent family' have frustrations for their past and current family. Also they have mental conflicts for their family better than another group.

  • PDF

A Study on the Qualitative Evaluation Factors for Mobile Game Company (모바일게임 기업의 정성적 평가요인에 관한 연구)

  • Choi, Seok Kyun;Hwangbo, Yun;Rhee, Do Yun
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
    • /
    • v.8 no.3
    • /
    • pp.125-146
    • /
    • 2013
  • Nowadays, the performance of the mobile game sales is influencing the ranking of game companies listed on KOSDAQ. In the meantime, venture capital companies had focused on online game. Recently, however, they have great interest in mobile games and mobile game companies. In addition, angel investors and accelerators are increasing investment for the mobile game companies. The most important issues for mobile game investor is how to evaluate the mobile game companies and their contents. Therefore, this study derived the evaluation factors for the mobile game company. And research method converged of the opinions of both supply side and demand side of the game industry. Ten professionals who are responsible for the supply of the game industry and CEO group & development experts of game development company were selected for survey in this study. Also ten professionals who are responsible for the demand of the game industry and the investment company were selected for survey in this study. And Delphi technique was performed according to the survey. Management skills, development capabilities, game play, feasibility, operational capabilities has emerged as five evaluation factors to evaluate the mobile game company. And the 20 sub-factors including CEO's reliability were derived. AHP(Analytic Hierarchy Process) theory is applied to analyze the importance of the qualitative elements which were derived by Delphi technique. As a result, the analysis hierarchy of evaluation factors for the mobile game company was created. Pair-wise comparison for each element was performed to analyze the importance. As a result, 'Core fun of the game' (12,2%), 'Involvement of the game' (10.3%), 'Security Reliability' (8.9%), 'Core developers' ability' (7.6%) appeared in order of importance. The significance of this study is offering more objective methodology for realistic assessment and importance of elements to evaluate mobile game company.

  • PDF

Development of Internet Information Push-Delivery System Design of Smoking Cessation for Health Promotion (지역주민의 건강증진을 위한 인터넷 금연 강화 프로그램 개발)

  • Kim, Young-Bok;Shin, Jun-Ho;Kim, Shin-Woel
    • Journal of agricultural medicine and community health
    • /
    • v.29 no.2
    • /
    • pp.287-301
    • /
    • 2004
  • Objectives: The development of internet programs for smoking cessation was motivated to quit smoking in the large group of smokers. This personalized program consisted of tailored message to consider the smokers characteristics, and contain the informations on the outcomes of smoking cessation and the skills to be used in the quit attempts. The purpose of this study was to develop the internet management program and information push-delivery system for smoking cessation to encourage the personal intention to quit smoking. Methods: We conducted in 3 steps as developing push service to encourage intention of smoking cessation, analyzing problems of smoking cessation program through the pilot test and suggesting improvements by implication stages. Results: This program is delivered for 30 days. if the participants do not fail to quit smoking. The contents consisted of 13 stages which were divided on starting period. practical period, maintenance period and success period. And push service afforded the tailored message to participants using their e-mail. According to the evaluation of pilot test, the problems of internet information push-delivery service for smoking cessation were the over-tasks per visiting time, recording style of participants, difficulty of terms and sentences, lack of visual effects, absence of follow-up module and unsuitable link with main homepage. Improvements were divided on 3 stages by implication period. The first stage included the immediate improvements as improving link with homepage, modifying menu of smoking information and upload file of notice part. The second stage included the short term improvements as alleviating condition of withdrawal, coordinating start stage of retrial, modifying errors of information push-delivery service and addition of educational materials. The third stage included the long term improvements as development of follow-up module, cost-effectiveness evaluation, reducing contents quantity, introduction of checking style, compensation of graphics effect and review for SMS utilization. Conclusions: This program contribute to improving smoking cessation rate. Therefore this program should be tested in a community to evaluate the effectiveness. To promote the effectiveness, this program should be developed the contents and the strategies for various targets, and established the follow-up system for ex-smokers.

  • PDF

A SURVEY OF DENTAL TREATMENT UNDER OUTPATIENT GENERAL ANESTHESIA IN DEPARTMENT OF PEDIATRIC DENTISTRY AND CLINIC FOR DISABLED AT YONSEI UNIVERSITY DENTAL HOSPITAL (연세대학교 치과대학병원 소아치과 및 장애인 클리닉에서 시행된 외래 전신마취하의 치료에 대한 연구)

  • Lee, Dong-Woo;Song, Je-Seon;Choi, Hyung-Jun;Kang, Jeong-Wan;Lee, Jae-Ho
    • Journal of the korean academy of Pediatric Dentistry
    • /
    • v.37 no.1
    • /
    • pp.65-72
    • /
    • 2010
  • General anesthesia has been researched and developed in dentistry as on type of management technique to sedate patients who may be uncontrollable or require medical consideration. There has been continuous research into this area, but analysis of large set of patients over a sustained period of time is lacking. Thus, this study analyzes the records of patients who received general anesthesia at the Yonsei University Dental Hospital Department of Pediatric and Clinic for the Disabled. 1. Patient's age ranged from 1 to 66, with under 5 being the largest group with 410 members(38.5%). The study included more men than women, with 695 male members(65.3%). 2. Type of dental procedure performed were as follows(per person) : 5.6 Dental restoration; 2.3 Endodontic treatment of deciduous and primary teeth; 2.5 preformed crowning; and 1.6 extractions. Procedures took an average of 100 minutes. 3. 1022 patients(95.9%) received dental care under general anesthesia once and 43 patients(4.1%) received dental care under general anesthesia two or more times. Dentistry under general anesthesia has the many benefit. However, without appropriate post-treatment care, it is difficult to maintain good oral health. Therefore, it is important to improve the efficiency and safety of general anesthesia through future research.

Research on the Factors that Affect Consumption Behaviors of Ethnic Food Restaurants (외국음식전문점 이용행동에 영향을 미치는 요인에 관한 연구)

  • Jung, Hyung-Shik;Kim, Young-Shim
    • CRM연구
    • /
    • v.2 no.2
    • /
    • pp.1-19
    • /
    • 2009
  • In an attempt to explore the consumption behaviors of customers regarding ethnic food restaurants the present study examined the effects of consumer characteristics, accessibility of ethnic food restaurants, product characteristics, and social factors on the customer behavior towards ethnic food restaurants, and further investigated the causal relationship between the customer behavior and his or her intent to reuse. A questionnaire survey was conducted approximately for a month with domestic consumers who had tried foreign cuisines. A total of 230 questionnaires were distributed and 215 questionnaires were collected, of which 210 were used in the final analysis excluding five due to inadequate responses. The finding of the study were as follows. First, of the consumers' lifestyles category the gourmet oriented did not yield significant effect on subjective norm or other consumption behavior, whereas the trend oriented had noticeable influence on both factors. Second, while consumers' diversity-seeking characteristic did not affect subjective norm, it affected consumption behavior of ethic food restaurants. The results seem to indicate that the diversity-seeking characteristic is more to one's individual attributes, rather than being influenced by others. Third, ethnic food restaurant's consumption accessibilities strongly influenced the subjective norm, suggesting that in using the ethnic food restaurants, the more convenient the accessibility is, the higher the possibility of use from influenced reference group. However, when consumers previously had not been exposed to ethnic cuisines, convenient accessibility was not able to overcome the barriers of consumer reluctance, nor directly shape positive behaviors. Fourth, while national uniqueness of ethnic food did not affect subjective norm, the uniqueness did have positive impact on consumption behavior of foreign ethnic food restaurants. Fifth, consumer's subjective norm positively influenced both consumption behavior of ethnic food restaurants and their intent for future use. Lastly, consumption behavior toward foreign ethnic food restaurants positively influenced consumer's intent for future use, indicating that it would be most imperative and effective to first help reinforce positive attitude in oder to encourage a more use of ethnic food restaurants.

  • PDF

Effects of Dietary Mugwort (Artemisia iwayomogi Kitamura) Powder Supplementation on Growing Performance in Pig (인진쑥(Artemisia iwayomogi Kitamura) 분말 급여가 돼지 생산성에 미치는 영향)

  • Ha, Im-Jung;Jeong, Mi-Ae;Kim, Byung-Uk;Kim, Jong-Duk;Ryu, Yeon-Sun;Kim, Sam-Woong;Lee, Chul-Young;Jung, Ki-Hwa;Cho, Kwang-Keun
    • Journal of Life Science
    • /
    • v.21 no.1
    • /
    • pp.110-118
    • /
    • 2011
  • This study was conducted to investigate growth performance in weanling and growing pigs supplemented with mugwort powder as an antibiotic replacement. To examine the effects of antibiotic replacement, 0 (control, with and without antibiotics), 1, and 1.5% mugwort powder was supplemented into the basal diet. Pigs raised with a diet of 1.0% mugwort powder had improved average daily gain and feed conversion rate during 23~37 d feeding. During 40~59 and 63~97 d feeding periods, there were no differences between average daily gain in pigs fed no antibiotics and those given a 1% mugwort powder diet, whereas feed conversion rate of pigs given a 1.5% mugwort powder diet and average daily gain of pigs fed no antibiotics were lower than those of any other diet group. In conclusion, this study suggests that the 1.0% supplementation of mugwort in place of antibiotics is an invaluable feed additive as a physiologically activated material.

Analysis of Epidemiological Characteristics, PFGE Typing and Antibiotic Resistance of Pathogenic Escherichia coli Strains Isolated from Gyeonggi-do (경기도에서 분리한 병원성대장균의 역학적 특성 및 PFGE, 항생제 내성 연구)

  • Kim, Kyung-A;Yong, Kum-Chan;Jeong, Jin-A;Huh, Jeong-Weon;Hur, Eun-Seon;Park, Sung-Hee;Choi, Yun-Sook;Yoon, Mi-Hye;Lee, Jong-Bok
    • Korean Journal of Microbiology
    • /
    • v.50 no.4
    • /
    • pp.285-295
    • /
    • 2014
  • This study was conducted to survey the epidemiological characteristics and the isolated strains for pathogenic E. coli which was the major causative organisms for food poisoning occurred at school food services in the Gyeonggi-do area during the past three years. We investigated 19 accidents of food-borne disease outbreaks by pathogenic E. coli at school food services from 2010 to 2012. Food-borne disease outbreaks by pathogenic E. coli were usually occurred at direct management type (18 accidents, 95%) and high schools. For the seasonal factors, 13 accidents (65%) were occurred in June to September, especially the end of August and September after the summer holidays. The first patients were occurred on Wednesday (7 accidents, 37%) and Thursday (7 accidents, 37%), and they were mainly reported on Thursday (7 accidents, 37%) and Friday (5 accidents, 26%). The exposure of risk was estimated in Monday (4 accidents, 21%), Tuesday (7 accidents, 37%) and Wednesday (4 accidents, 21%), and kimchi (5 accidents, 50%) was estimated as the food of the high risk responsible for the outbreaks. 98 isolates of pathogenic E. coli consisted of PEC (50%), ETEC (34%), EAEC (15%), and EHEC (1%). The antibiotic resistance of pathogenic E. coli showed in the descending order of ampicilline (40%), nalidixic acid (37%), trimethoprim/sulfamethoxazole (24%), and tetracycline (19%). The antibiotics of second and third generation cephalosporins, cabarpenem, aminoglycosides, and second generation quinolones had antimicrobial susceptibilities and cefalotin, ampicillin/sulbactam and chloramphenicol showed medium resistance at 29%, 25%, and 6% respectively, and 70% of isolates were resistant to more than one antibiotic. By the PFGE analysis, they were classified into nine major groups and 31 profiles with 57% pattern similarity. It was very difficult to find the correlation of antimicrobial susceptibilities and genotype in the small scale-food poisoning, but the similarity of antimicrobial resistance and PFGE patterns in the large scale-food poisoning enabled the outbreaks to estimate the same pathotype of E. coli derived from identical origins.

A Geographical Study of Therapeutic Spaces after the Disaster of the MV Sewol in a Local Community (세월호 참사 이후 지역 커뮤니티에 형성된 치유의 공간에 대한 지리적 고찰)

  • Park, Sookyung
    • Journal of the Korean Geographical Society
    • /
    • v.52 no.1
    • /
    • pp.25-53
    • /
    • 2017
  • The ultimate goal of this research is to examine the geographical characteristics of therapeutic spaces where have been appeared in Wa-dong and Gojan-dong, Ansan-si after the disaster of the MV Sewol. As looking into the inside, the aim of the therapeutic spaces, which cover each target group (victims) individually, is various and different because the disaster of the MV Sewol generated various direct and indirect victims requiring healing. The therapeutic spaces are estimated at about 10 organizations and are leaded by private agents predominantly. Furthermore, the therapeutic spaces are located near, but are aside from Danwon high school where many students are reported killed and injured in the incident. And the therapeutic spaces provide simple and repetitive diversions, for example, having a meal, knitting and studying, rather than special programs to restore a broken daily life to the original state. On the basis of such a background, the geographical characteristics of the therapeutic spaces related to the disaster of the MV Sewol can be summarized as follows; first, it seems that target groups accept the therapeutic spaces as the concept of place gradually. Even though most of the therapeutic spaces were suggested by third parties at first, target groups are involved in the management and recollection of their own therapeutic spaces as well as the plan for a future direction now; and consider the therapeutic spaces as exclusive properties. Second, the disaster of the MV Sewol have embedded collective trauma to not only direct victims, but extensive groups such as parents, brothers and sisters, relatives, friends and neighbors as noted earlier. Therefore, the therapeutic spaces support comprehensive target groups; but each therapeutic space is not overlapped each other. However, to solve collective trauma in a local community effectively, the therapeutic spaces are networked closely and build a regular cooperative system. Third, a continuous memory is mentioned as an important point to overcome collective trauma, but some phenomena such as fatigue and conflict with neighbors, out-migrants and a faded atmosphere as time passes act as risk factors in Ansan-si. To keep a continuous memory, the therapeutic spaces attempt the recovery of local communities and devise various events, for example, cultural performances; furthermore, are closely connected with external organizations.

  • PDF