• Title/Summary/Keyword: Web Based Learning

Search Result 1,321, Processing Time 0.025 seconds

Financial Fraud Detection using Text Mining Analysis against Municipal Cybercriminality (지자체 사이버 공간 안전을 위한 금융사기 탐지 텍스트 마이닝 방법)

  • Choi, Sukjae;Lee, Jungwon;Kwon, Ohbyung
    • Journal of Intelligence and Information Systems
    • /
    • v.23 no.3
    • /
    • pp.119-138
    • /
    • 2017
  • Recently, SNS has become an important channel for marketing as well as personal communication. However, cybercrime has also evolved with the development of information and communication technology, and illegal advertising is distributed to SNS in large quantity. As a result, personal information is lost and even monetary damages occur more frequently. In this study, we propose a method to analyze which sentences and documents, which have been sent to the SNS, are related to financial fraud. First of all, as a conceptual framework, we developed a matrix of conceptual characteristics of cybercriminality on SNS and emergency management. We also suggested emergency management process which consists of Pre-Cybercriminality (e.g. risk identification) and Post-Cybercriminality steps. Among those we focused on risk identification in this paper. The main process consists of data collection, preprocessing and analysis. First, we selected two words 'daechul(loan)' and 'sachae(private loan)' as seed words and collected data with this word from SNS such as twitter. The collected data are given to the two researchers to decide whether they are related to the cybercriminality, particularly financial fraud, or not. Then we selected some of them as keywords if the vocabularies are related to the nominals and symbols. With the selected keywords, we searched and collected data from web materials such as twitter, news, blog, and more than 820,000 articles collected. The collected articles were refined through preprocessing and made into learning data. The preprocessing process is divided into performing morphological analysis step, removing stop words step, and selecting valid part-of-speech step. In the morphological analysis step, a complex sentence is transformed into some morpheme units to enable mechanical analysis. In the removing stop words step, non-lexical elements such as numbers, punctuation marks, and double spaces are removed from the text. In the step of selecting valid part-of-speech, only two kinds of nouns and symbols are considered. Since nouns could refer to things, the intent of message is expressed better than the other part-of-speech. Moreover, the more illegal the text is, the more frequently symbols are used. The selected data is given 'legal' or 'illegal'. To make the selected data as learning data through the preprocessing process, it is necessary to classify whether each data is legitimate or not. The processed data is then converted into Corpus type and Document-Term Matrix. Finally, the two types of 'legal' and 'illegal' files were mixed and randomly divided into learning data set and test data set. In this study, we set the learning data as 70% and the test data as 30%. SVM was used as the discrimination algorithm. Since SVM requires gamma and cost values as the main parameters, we set gamma as 0.5 and cost as 10, based on the optimal value function. The cost is set higher than general cases. To show the feasibility of the idea proposed in this paper, we compared the proposed method with MLE (Maximum Likelihood Estimation), Term Frequency, and Collective Intelligence method. Overall accuracy and was used as the metric. As a result, the overall accuracy of the proposed method was 92.41% of illegal loan advertisement and 77.75% of illegal visit sales, which is apparently superior to that of the Term Frequency, MLE, etc. Hence, the result suggests that the proposed method is valid and usable practically. In this paper, we propose a framework for crisis management caused by abnormalities of unstructured data sources such as SNS. We hope this study will contribute to the academia by identifying what to consider when applying the SVM-like discrimination algorithm to text analysis. Moreover, the study will also contribute to the practitioners in the field of brand management and opinion mining.

Prediction of Key Variables Affecting NBA Playoffs Advancement: Focusing on 3 Points and Turnover Features (미국 프로농구(NBA)의 플레이오프 진출에 영향을 미치는 주요 변수 예측: 3점과 턴오버 속성을 중심으로)

  • An, Sehwan;Kim, Youngmin
    • Journal of Intelligence and Information Systems
    • /
    • v.28 no.1
    • /
    • pp.263-286
    • /
    • 2022
  • This study acquires NBA statistical information for a total of 32 years from 1990 to 2022 using web crawling, observes variables of interest through exploratory data analysis, and generates related derived variables. Unused variables were removed through a purification process on the input data, and correlation analysis, t-test, and ANOVA were performed on the remaining variables. For the variable of interest, the difference in the mean between the groups that advanced to the playoffs and did not advance to the playoffs was tested, and then to compensate for this, the average difference between the three groups (higher/middle/lower) based on ranking was reconfirmed. Of the input data, only this year's season data was used as a test set, and 5-fold cross-validation was performed by dividing the training set and the validation set for model training. The overfitting problem was solved by comparing the cross-validation result and the final analysis result using the test set to confirm that there was no difference in the performance matrix. Because the quality level of the raw data is high and the statistical assumptions are satisfied, most of the models showed good results despite the small data set. This study not only predicts NBA game results or classifies whether or not to advance to the playoffs using machine learning, but also examines whether the variables of interest are included in the major variables with high importance by understanding the importance of input attribute. Through the visualization of SHAP value, it was possible to overcome the limitation that could not be interpreted only with the result of feature importance, and to compensate for the lack of consistency in the importance calculation in the process of entering/removing variables. It was found that a number of variables related to three points and errors classified as subjects of interest in this study were included in the major variables affecting advancing to the playoffs in the NBA. Although this study is similar in that it includes topics such as match results, playoffs, and championship predictions, which have been dealt with in the existing sports data analysis field, and comparatively analyzed several machine learning models for analysis, there is a difference in that the interest features are set in advance and statistically verified, so that it is compared with the machine learning analysis result. Also, it was differentiated from existing studies by presenting explanatory visualization results using SHAP, one of the XAI models.

Automatic Target Recognition Study using Knowledge Graph and Deep Learning Models for Text and Image data (지식 그래프와 딥러닝 모델 기반 텍스트와 이미지 데이터를 활용한 자동 표적 인식 방법 연구)

  • Kim, Jongmo;Lee, Jeongbin;Jeon, Hocheol;Sohn, Mye
    • Journal of Internet Computing and Services
    • /
    • v.23 no.5
    • /
    • pp.145-154
    • /
    • 2022
  • Automatic Target Recognition (ATR) technology is emerging as a core technology of Future Combat Systems (FCS). Conventional ATR is performed based on IMINT (image information) collected from the SAR sensor, and various image-based deep learning models are used. However, with the development of IT and sensing technology, even though data/information related to ATR is expanding to HUMINT (human information) and SIGINT (signal information), ATR still contains image oriented IMINT data only is being used. In complex and diversified battlefield situations, it is difficult to guarantee high-level ATR accuracy and generalization performance with image data alone. Therefore, we propose a knowledge graph-based ATR method that can utilize image and text data simultaneously in this paper. The main idea of the knowledge graph and deep model-based ATR method is to convert the ATR image and text into graphs according to the characteristics of each data, align it to the knowledge graph, and connect the heterogeneous ATR data through the knowledge graph. In order to convert the ATR image into a graph, an object-tag graph consisting of object tags as nodes is generated from the image by using the pre-trained image object recognition model and the vocabulary of the knowledge graph. On the other hand, the ATR text uses the pre-trained language model, TF-IDF, co-occurrence word graph, and the vocabulary of knowledge graph to generate a word graph composed of nodes with key vocabulary for the ATR. The generated two types of graphs are connected to the knowledge graph using the entity alignment model for improvement of the ATR performance from images and texts. To prove the superiority of the proposed method, 227 documents from web documents and 61,714 RDF triples from dbpedia were collected, and comparison experiments were performed on precision, recall, and f1-score in a perspective of the entity alignment..

Game Based Online Contents Development in Middle School Mathematics (중학교 수학교과의 온라인 게임형 콘텐츠 개발)

  • Cho, Eun-Soon;Kim, In-Sook
    • The Journal of the Korea Contents Association
    • /
    • v.7 no.9
    • /
    • pp.248-256
    • /
    • 2007
  • The purpose of this study is to design, develope, and deploy of online game content in middle school mathematics. This study analyzed related literature review, case studies, and educational game web sites for seeking better applicable design strategies. After serious discussion with experts based the design ideas, this study established its own educational game design model and it was applied to develop algebraic function lesson for middle school students. The developed content also was deployed in real classroom setting to see how students received the game contents and how. well they processed the design procedures and activities. We found that educational online game content, especially when applied to mathematics subject, can be effective in students interests and their motivations. We also observed that there were a few managerial errors such as need for detailed guidance for game, cumulative game results for later feedback, and so on. This study concluded that educational game contents should be able to widely spread out to get students' learning interests and strong motivation as well. We suggest that related research should be done toward to other subject than mathmatics and various students age groups.

Dynamic Distributed Adaptation Framework for Quality Assurance of Web Service in Mobile Environment (모바일 환경에서 웹 서비스 품질보장을 위한 동적 분산적응 프레임워크)

  • Lee, Seung-Hwa;Cho, Jae-Woo;Lee, Eun-Seok
    • The KIPS Transactions:PartD
    • /
    • v.13D no.6 s.109
    • /
    • pp.839-846
    • /
    • 2006
  • Context-aware adaptive service for overcoming the limitations of wireless devices and maintaining adequate service levels in changing environments is becoming an important issue. However, most existing studies concentrate on an adaptation module on the client, proxy, or server. These existing studies thus suffer from the problem of having the workload concentrated on a single system when the number of users increases md, and as a result, increases the response time to a user's request. Therefore, in this paper the adaptation module is dispersed and arranged over the client, proxy, and server. The module monitors the contort of the system and creates a proposition as to the dispersed adaptation system in which the most adequate system for conducting operations. Through this method faster adaptation work will be made possible even when the numbers of users increase, and more stable system operation is made possible as the workload is divided. In order to evaluate the proposed system, a prototype is constructed and dispersed operations are tested using multimedia based learning content, simulating server overload and compared the response times and system stability with the existing server based adaptation method. The effectiveness of the system is confirmed through this results.

A Fashion Design Recommender Agent System using Collaborative Filtering and Sensibilities related to Textile Design Factors (텍스타일 기반의 협력적 필터링 기술과 디자인 요소에 따른 감성 분석을 이용한 패션 디자인 추천 에이전트 시스템)

  • 정경용;나영주;이정현
    • Journal of KIISE:Computing Practices and Letters
    • /
    • v.10 no.2
    • /
    • pp.174-188
    • /
    • 2004
  • In the life environment changed with not only the quality and the price of the products but also the material abundance, it is the most crucial factor for the strategy of product sales to investigate consumer's sensibility and preference degree. In this perspective, it is necessary to design and merchandise the products in cope with each consumer's sensibility and needs as well as its functional aspects. In this paper, we propose the Fashion Design Recommender Agent System (FDRAS-pro) for textile design applying collaborative filtering personalization technique as one of the methods of material development centered on consumer's sensibility and preference. For a collaborative filtering system based on textile, Representative-Attribute Neighborhood is adopted to determine the number or neighbors that will be used for preferences estimation. Pearson's Correlation Coefficient is used to calculate similarity weights among users. We build a database founded on the sensibility adjectives to develop textile designs by extracting the representative sensibility adjectives from users' sensibility and preferences about textile designs. FDRAS-pro recommends textile designs to a customer who has a similar propensity about textile. To investigate the sensibility and emotion according to the effect of design factors, fertile designs were analyzed in terms of 9 design factors, such as, motif source, motif-background ratio, motif variation, motif interpretation, motif arrangement, motif articulation, hue contrast, value contrast, chroma contrast. Finally, we plan to conduct empirical applications to verify the adequacy and the validity of our system.

Design and Implementation of Thesaurus System for Geological Terms (지질용어 시소러스 시스템의 설계 및 구축)

  • Hwang, Jaehong;Chi, KwangHoon;Han, JongGyu;Yeon, Young Kwang;Ryu, Keun Ho
    • Journal of the Korean Association of Geographic Information Studies
    • /
    • v.10 no.2
    • /
    • pp.23-35
    • /
    • 2007
  • With the development of semantic web technologies in information retrieval area, the necessity for thesaurus is recently increasing along with internet lexicons. A thesaurus is the combination of classification and a lexicon, and is the topic map of knowledge structure expressing relations among concepts(terms) subject to human knowledge activities such as learning and research using formally organized and controlled index terms for clarifying the context of superordinate and subordinate concepts. However, although thesaurus are regarded as essential tools for controlling and standardizing terms and searching and processing information efficiently, we do not have a Korean thesaurus for geology. To build a thesaurus, we need standardized and well-defined guidelines. The standardized guidelines enable efficient information management and help information users use correct information easily and conveniently. The present study purposed to build a thesaurus system with terms used in geology. For this, First, we surveyed related works for standardizing geological terms in Korea and other countries. Second, we defined geological topics in 15 areas and prepared a classification system(draft) for each topic. Third, based on the geological thesaurus classification system, we created the specification of geological thesaurus. Lastly, we designed and implemented an internet-based geological thesaurus system using the specification.

  • PDF

An Improvement in K-NN Graph Construction using re-grouping with Locality Sensitive Hashing on MapReduce (MapReduce 환경에서 재그룹핑을 이용한 Locality Sensitive Hashing 기반의 K-Nearest Neighbor 그래프 생성 알고리즘의 개선)

  • Lee, Inhoe;Oh, Hyesung;Kim, Hyoung-Joo
    • KIISE Transactions on Computing Practices
    • /
    • v.21 no.11
    • /
    • pp.681-688
    • /
    • 2015
  • The k nearest neighbor (k-NN) graph construction is an important operation with many web-related applications, including collaborative filtering, similarity search, and many others in data mining and machine learning. Despite its many elegant properties, the brute force k-NN graph construction method has a computational complexity of $O(n^2)$, which is prohibitive for large scale data sets. Thus, (Key, Value)-based distributed framework, MapReduce, is gaining increasingly widespread use in Locality Sensitive Hashing which is efficient for high-dimension and sparse data. Based on the two-stage strategy, we engage the locality sensitive hashing technique to divide users into small subsets, and then calculate similarity between pairs in the small subsets using a brute force method on MapReduce. Specifically, generating a candidate group stage is important since brute-force calculation is performed in the following step. However, existing methods do not prevent large candidate groups. In this paper, we proposed an efficient algorithm for approximate k-NN graph construction by regrouping candidate groups. Experimental results show that our approach is more effective than existing methods in terms of graph accuracy and scan rate.

Development of Online Continuing Education Courses on National Health Examination for Community Health Nurses: Using the Rapid Prototyping Method (지역사회 간호사를 위한 건강검진 온라인 교육안 개발: Rapid prototyping method를 활용)

  • Kim, Eun-Ha;Kim, Kye-Ha;Bae, Kyung-Eui
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.20 no.8
    • /
    • pp.250-263
    • /
    • 2019
  • This study was conducted to develop an online education program for visiting health nurses on National Health Examination. The study period was from November 2016 to December 2017. The program was developed in stages using rapid prototyping methodology. 1) Learners' needs were identified through literature review and focus group interviews (FGIs) with visiting health nurses and stake-holders in the field. 2) The contents of the education program including counseling strategies regarding the heath of visiting health nurses were developed. 3) Online education materials were developed and piloted amongst learners. 4) The contents of educational programs were classified into eight learning modules, and online education drafts were pilot tested. 5) Based on feedback from learners, this program was revised and a web-based continuing education program for community nurses was developed. These education programs effectively assisted nurses with counseling regarding health examinations during visiting health nursing care. Therefore, the online continuing education program may be a very effective educational approach to improving nurses competency.

A Dynamic exploration of Constructivism Research based on Citespace Software in the Filed of Education (교육학 분야에서 CiteSpace에 기초한 구성주의 연구 동향 탐색)

  • Jiang, Yuxin;Song, Sun-Hee
    • The Journal of the Korea Contents Association
    • /
    • v.22 no.5
    • /
    • pp.576-584
    • /
    • 2022
  • As an important branch of cognitive psychology, "constructivism" is called a "revolution" in contemporary educational psychology, which has a profound influence on the field of pedagogy and psychology. Based on "WOS" database, this study selects "WOS Core database" and "KCI database", uses CiteSpace visualization software as analysis tool, and makes knowledge map analysis on the research literature of "constructivism" in the field of education in recent 35 years. Analysis directions include annual analysis, network connection analysis by country(region) branch, author, institution or University, and keyword analysis. The purpose of the analysis is to grasp the subject areas, research hotspots and future trends of the research on constructivism, and to provide theoretical reference for the research on constructivism. There are three conclusions from the study. 1. Studies on the subject of constructivism have continued from the 1980s to the present. It is now in a period of steady development. 2. Countries concerned with the subject of constructivism mainly include the United States, Canada, Britain, Australia and the Netherlands. The main research institutions and authors are mainly located in these countries. 3. Currently, the keywords constructivism research focus on the clusters of "instructional strategies", and the development of science and technology is affecting individual learning. In the future, instructional strategies will become the focus of structural constructivism research. With the development of instructional technology, it is necessary to conduct research related to the development of new teaching models.