• Title/Summary/Keyword: an Evaluation Model of IS Services

Search Result 314, Processing Time 0.032 seconds

Formal Model of Extended Reinforcement Learning (E-RL) System (확장된 강화학습 시스템의 정형모델)

  • Jeon, Do Yeong;Song, Myeong Ho;Kim, Soo Dong
    • Journal of Internet Computing and Services
    • /
    • v.22 no.4
    • /
    • pp.13-28
    • /
    • 2021
  • Reinforcement Learning (RL) is a machine learning algorithm that repeat the closed-loop process that agents perform actions specified by the policy, the action is evaluated with a reward function, and the policy gets updated accordingly. The key benefit of RL is the ability to optimze the policy with action evaluation. Hence, it can effectively be applied to developing advanced intelligent systems and autonomous systems. Conventional RL incoporates a single policy, a reward function, and relatively simple policy update, and hence its utilization was limited. In this paper, we propose an extended RL model that considers multiple instances of RL elements. We define a formal model of the key elements and their computing model of the extended RL. Then, we propose design methods for applying to system development. As a case stud of applying the proposed formal model and the design methods, we present the design and implementation of an advanced car navigator system that guides multiple cars to reaching their destinations efficiently.

Design and Evaluation of a Personalized Search Service Model Based on Web Portal User Activities (웹 포털 이용자 로그 데이터에 기반한 개인화 검색 서비스 모형의 설계 및 평가)

  • Lee, So-Young;Chung, Young-Mee
    • Journal of the Korean Society for information Management
    • /
    • v.23 no.4 s.62
    • /
    • pp.179-196
    • /
    • 2006
  • This study proposes an expanded model of personalized search service based on community activities on a Korean Web portal. The model is composed of defining subject categories of users, providing personalized search results, and recommending additional subject categories and queries. Several experiments were performed to verify the feasibility and effectiveness of the proposed model. It was found that users' activities on community services provide valuable data for identifying their Interests, and the personalized search service increases users' satisfaction.

Air Threat Evaluation System using Fuzzy-Bayesian Network based on Information Fusion (정보 융합 기반 퍼지-베이지안 네트워크 공중 위협평가 방법)

  • Yun, Jongmin;Choi, Bomin;Han, Myung-Mook;Kim, Su-Hyun
    • Journal of Internet Computing and Services
    • /
    • v.13 no.5
    • /
    • pp.21-31
    • /
    • 2012
  • Threat Evaluation(TE) which has air intelligence attained by identifying friend or foe evaluates the target's threat degree, so it provides information to Weapon Assignment(WA) step. Most of TE data are passed by sensor measured values, but existing techniques(fuzzy, bayesian network, and so on) have many weaknesses that erroneous linkages and missing data may fall into confusion in decision making. Therefore we need to efficient Threat Evaluation system that can refine various sensor data's linkages and calculate reliable threat values under unpredictable war situations. In this paper, we suggest new threat evaluation system based on information fusion JDL model, and it is principle that combine fuzzy which is favorable to refine ambiguous relationships with bayesian network useful to inference battled situation having insufficient evidence and to use learning algorithm. Finally, the system's performance by getting threat evaluation on an air defense scenario is presented.

Development and Application d A Comprehensive Case Management Model for Helping North Korean Refugees' Psycho-Social Adjustment in South Korea (탈북자의 사회적응 지원을 위한 종합형 사례관리 모형의 제시와 그 실천)

  • Um, Myung-Yong
    • Korean Journal of Social Welfare
    • /
    • v.37
    • /
    • pp.271-306
    • /
    • 1999
  • This study aimed to present a comprehensive case management model which might be helpful for social workers in community social welfare agencies who works with North Korean refugees for their psychosocial adjustment in South Korea. After being constructed, the model was put into practice upon North Korean refugees. This article described the whole process of model construction and its application. Detail steps taken in this research include: (a) The researcher had 20 unstructured individual interviews with 11 North Korean refugees in order to identify psychosocial problems that need social workers' intervention; (b) Based upon the problems identified through interviews and previous literature review, program components were identified and sorted out into two phases, one of which is therapeutic phase, the other is case management phase; (c) By interlocking the two phases, the researcher proposed a comprehensive case management model whereby North Korean refugees can get psychosocial services as well as linkage services in an interactive fashion; (d) The utility of the proposed model was examined by using a couple of North Korean refugees who initially showed complicated psycho-social-economic problems. The therapeutic phase employed a cognitive-behavioral approach. The case management phase consists of: assessment and diagnosis; service planning and resource identification; linking of clients to needed services; monitoring of service delivery; and evaluation. Although the program could not go through with because of the limited contacts with North Korean refugees for security reasons, the program was turned out to be very useful in helping North Korean refugees' settling-down in South Korea. Implications for the application of the proposed model was discussed along with limitations of this study.

  • PDF

A Study on the Evaluation of Optimal Program Applicability for Face Recognition Using Machine Learning (기계학습을 이용한 얼굴 인식을 위한 최적 프로그램 적용성 평가에 대한 연구)

  • Kim, Min-Ho;Jo, Ki-Yong;You, Hee-Won;Lee, Jung-Yeal;Baek, Un-Bae
    • Korean Journal of Artificial Intelligence
    • /
    • v.5 no.1
    • /
    • pp.10-17
    • /
    • 2017
  • This study is the first attempt to raise face recognition ability through machine learning algorithm and apply to CRM's information gathering, analysis and application. In other words, through face recognition of VIP customer in distribution field, we can proceed more prompt and subdivided customized services. The interest in machine learning, which is used to implement artificial intelligence, has increased, and it has become an age to automate it by using machine learning beyond the way that a person directly models an object recognition process. Among them, Deep Learning is evaluated as an advanced technology that shows amazing performance in various fields, and is applied to various fields of image recognition. Face recognition, which is widely used in real life, has been developed to recognize criminals' faces and catch criminals. In this study, two image analysis models, TF-SLIM and Inception-V3, which are likely to be used for criminal face recognition, were selected, analyzed, and implemented. As an evaluation criterion, the image recognition model was evaluated based on the accuracy of the face recognition program which is already being commercialized. In this experiment, it was evaluated that the recognition accuracy was good when the accuracy of the image classification was more than 90%. A limit of our study which is a way to raise face recognition is left as a further research subjects.

Major Class Recommendation System based on Deep learning using Network Analysis (네트워크 분석을 활용한 딥러닝 기반 전공과목 추천 시스템)

  • Lee, Jae Kyu;Park, Heesung;Kim, Wooju
    • Journal of Intelligence and Information Systems
    • /
    • v.27 no.3
    • /
    • pp.95-112
    • /
    • 2021
  • In university education, the choice of major class plays an important role in students' careers. However, in line with the changes in the industry, the fields of major subjects by department are diversifying and increasing in number in university education. As a result, students have difficulty to choose and take classes according to their career paths. In general, students choose classes based on experiences such as choices of peers or advice from seniors. This has the advantage of being able to take into account the general situation, but it does not reflect individual tendencies and considerations of existing courses, and has a problem that leads to information inequality that is shared only among specific students. In addition, as non-face-to-face classes have recently been conducted and exchanges between students have decreased, even experience-based decisions have not been made as well. Therefore, this study proposes a recommendation system model that can recommend college major classes suitable for individual characteristics based on data rather than experience. The recommendation system recommends information and content (music, movies, books, images, etc.) that a specific user may be interested in. It is already widely used in services where it is important to consider individual tendencies such as YouTube and Facebook, and you can experience it familiarly in providing personalized services in content services such as over-the-top media services (OTT). Classes are also a kind of content consumption in terms of selecting classes suitable for individuals from a set content list. However, unlike other content consumption, it is characterized by a large influence of selection results. For example, in the case of music and movies, it is usually consumed once and the time required to consume content is short. Therefore, the importance of each item is relatively low, and there is no deep concern in selecting. Major classes usually have a long consumption time because they have to be taken for one semester, and each item has a high importance and requires greater caution in choice because it affects many things such as career and graduation requirements depending on the composition of the selected classes. Depending on the unique characteristics of these major classes, the recommendation system in the education field supports decision-making that reflects individual characteristics that are meaningful and cannot be reflected in experience-based decision-making, even though it has a relatively small number of item ranges. This study aims to realize personalized education and enhance students' educational satisfaction by presenting a recommendation model for university major class. In the model study, class history data of undergraduate students at University from 2015 to 2017 were used, and students and their major names were used as metadata. The class history data is implicit feedback data that only indicates whether content is consumed, not reflecting preferences for classes. Therefore, when we derive embedding vectors that characterize students and classes, their expressive power is low. With these issues in mind, this study proposes a Net-NeuMF model that generates vectors of students, classes through network analysis and utilizes them as input values of the model. The model was based on the structure of NeuMF using one-hot vectors, a representative model using data with implicit feedback. The input vectors of the model are generated to represent the characteristic of students and classes through network analysis. To generate a vector representing a student, each student is set to a node and the edge is designed to connect with a weight if the two students take the same class. Similarly, to generate a vector representing the class, each class was set as a node, and the edge connected if any students had taken the classes in common. Thus, we utilize Node2Vec, a representation learning methodology that quantifies the characteristics of each node. For the evaluation of the model, we used four indicators that are mainly utilized by recommendation systems, and experiments were conducted on three different dimensions to analyze the impact of embedding dimensions on the model. The results show better performance on evaluation metrics regardless of dimension than when using one-hot vectors in existing NeuMF structures. Thus, this work contributes to a network of students (users) and classes (items) to increase expressiveness over existing one-hot embeddings, to match the characteristics of each structure that constitutes the model, and to show better performance on various kinds of evaluation metrics compared to existing methodologies.

An Investigation of Factors Affecting Management Efficiency in Korean General Hospitals Using DEA Model (DEA모형을 이용한 종합병원의 효율성 측정과 영향요인)

  • Ahn, In-Whan;Yang, Dong-Hyun
    • Korea Journal of Hospital Management
    • /
    • v.10 no.1
    • /
    • pp.71-92
    • /
    • 2005
  • The purpose of this study is to analyze the efficiency in management of general hospitals and investigate the major factors on efficiency. Specifically, the management of each general hospital is evaluated by using Data Envelopment Analysis(DEA) technique which is a nonparametric statistical method for measurement of efficiency. Then, the influencing factors are investigated through analyses of Decision-Tree Model and Tobit Regression. The target hospitals were general hospitals in which bed sizes are between 200 and 500 among a total of 276 general hospitals. The main data of financial indicators were collected from 48 hospitals, and it was analyzed by using two statistical models. For Model I, three input and two output variables were used for efficiency evaluation. In particular, three input variables were the number of medical doctors, the number of paramedical personnel, and the bed size. And, two output variables were the numbers of inpatients and outpatients per year, adjusted by bed-size. The results of DEA analysis showed that only seven out of 48 hospitals(15%) turned out to be efficient. The decision-tree analysis also showed that there were six significant influencing factors for Model I. Six factors for Model I were Bed Occupancy Rate, Cost per Adjusted Inpatient, New Visit Ratio of Outpatients, Retired Ratio, Net Profit to Gross Revenues, Net Profit to Total Assets. In addition, the management efficiency of hospital is proved to increase as profit and patient-induced indicators increase and cost-related indicators decrease, by the Tobit regression model of independent variables derived from the decision-tree analysis. This study may be contributable to the development of analytic methodology regarding the efficiency of hospital management in that it suggests the synthetic measures by utilizing DEA model instead of suggesting simple ratio-analyzing results.

  • PDF

A Study of the Effect on the End-User Satisfaction Changing Information Center in Systems Perspective (시스템측면에서의 정보센터 개념변화가 사용자 만족도에 미치는 영향에 관한 연구)

  • 윤중현
    • Journal of the Korean Society for information Management
    • /
    • v.20 no.1
    • /
    • pp.75-91
    • /
    • 2003
  • The purpose of this study is to identify the new roles and services of information center that is affected by changing information technology and end-user computing environment. A user satisfaction model has been used and hypotheses are developed to find relationships information center service evaluation factors. The hypotheses have been tested with 41 user surveys. This study presents the relationship between certain information center management variables and the end-user satisfaction applying organization-wide information service. The result of this research can give an insight of the evaluation of information center service activities.

A Preliminary Study for the Curriculum Development of Community Care Coordinators: Educational Needs Analysis (지역사회 케어코디네이터 교육과정을 위한 기초연구: 교육요구도 분석)

  • Park, Han Nah;Yoon, Ju Young;Jang, Soong-Nang;Nam, Hye Jin
    • Research in Community and Public Health Nursing
    • /
    • v.33 no.2
    • /
    • pp.153-163
    • /
    • 2022
  • Purpose: A care coordinator is an emerging nursing professional role in South Korea. The purpose of this study was to identify educational needs and priorities for care coordinators among nurses. Methods: An online survey was conducted on 661 current or retired nurses from January 30 to February 28, 2021. A total of 17 essential competencies for care coordinators, recognized based on literature review, were used to analyze the educational needs. The data were analyzed using descriptive statistics, a paired t-test, and one-way analysis of variance with SPSS 25.0. The educational needs analysis was conducted by using a paired t-test, the Borich Needs Assessment Model, and the Locus for Focus Model. Results: Five contents were identified as the first priorities for educational needs: 'Health program planning and evaluation', 'Care planning', 'Coordinating community-based services', 'Case management', and 'Transitional care'. The second priorities for educational needs included 'Population health management' and 'Welfare resource linkages via communicating with social workers'. Conclusion: The priority items derived from this study offer underpinning insights for the development of care coordination training program.

Evaluation of Ground Effective Thermal Conductivity and Borehole Effective Thermal Resistance from Simple Line-Source Model (단순 선형열원 모델을 이용한 지중 유효 열전도도와 보어홀 유효 열저항 산정)

  • Sohn, Byong-Hu
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
    • /
    • v.19 no.7
    • /
    • pp.512-520
    • /
    • 2007
  • The design of a ground-source heat pump system includes specifications for a ground loop heat exchanger where the heat transfer rate depends on the effective thermal conductivity of the ground and the effective thermal resistance of the borehole. To evaluate these heat transfer properties, in-situ thermal response tests on four vertical test boreholes with different grouting materials were conducted by adding a monitored amount of heat to circulating water. The line-source method is applied to the temperature rise in an in-situ test and extended to also give an estimate of borehole effective thermal resistance. The effect of increasing thermal conductivity of the grouting materials from 0.818 to $1.104W/m^{\circ}C$ resulted in overall increases in effective thermal conductivity by 15.8 to 56.3% and reductions in effective thermal resistance by 13.0 to 31.1%.