• Title/Summary/Keyword: 아이템의 수

검색결과 554건 처리시간 0.029초

Reducing Noise Using Degree of Scattering in Collaborative Filtering System (협력적 여과 시스템에서 산포도를 이용한 잡음 감소)

  • Ko, Su-Jeong
    • The KIPS Transactions:PartB
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    • 제14B권7호
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    • pp.549-558
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    • 2007
  • Collaborative filtering systems have problems when users rate items and the rated results depend on their feelings, as there is a possibility that the results include noise. The method proposed in this paper optimizes the matrix by excluding irrelevant ratings as information for recommendations from a user-item matrix using dispersion. It reduces the noise that results from predicting preferences based on original user ratings by inflecting the information for items and users on the matrix. The method excludes the ratings values of the utmost limits using a percentile to supply the defects of coefficient of variance and composes a weighted user-item matrix by combining the user coefficient of variance with the median of ratings for items. Finally, the preferences of the active user are predicted based on the weighted matrix. A large database of user ratings for movies from the MovieLens recommender system is used, and the performance is evaluated. The proposed method is shown to outperform earlier methods significantly.

A CFG Based Automated Search Method of an Optimal Transcoding Path for Application Independent Digital Item Adaptation in Ubiquitous Environment (유비쿼터스 환경에서 응용 독립적 DIA를 위한 최적 트랜스코딩 경로의 CFG 기반 자동 탐색 방법)

  • Chon Sungmi;Lim Younghwan
    • The KIPS Transactions:PartB
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    • 제12B권3호
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    • pp.313-322
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    • 2005
  • In order to access digital items in a server via ubiquitous devices, the digital items should be adapted according to the system environment, device characteristics and user preferences. In ubiquitous environment, those device-dependent adaptation requirements are not statically determined and not predictable. Therefore an application specific adaptation mechanism can not be applied to a general digital item adaptation engine. In this paper, we propose an application independent digital item adaptation architecture which has a set of minimal transcoders, transcoding path generator for a required adaptation requirement, and adaptation scheduler. And a CFG based method of finding a sequence of multiple unit transcoders called a transcoding path Is described in detail followed by experimental results.

Discovering Association Rules using Item Clustering on Frequent Pattern Network (빈발 패턴 네트워크에서 아이템 클러스터링을 통한 연관규칙 발견)

  • Oh, Kyeong-Jin;Jung, Jin-Guk;Ha, In-Ay;Jo, Geun-Sik
    • Journal of Intelligence and Information Systems
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    • 제14권1호
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    • pp.1-17
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    • 2008
  • Data mining is defined as the process of discovering meaningful and useful pattern in large volumes of data. In particular, finding associations rules between items in a database of customer transactions has become an important thing. Some data structures and algorithms had been proposed for storing meaningful information compressed from an original database to find frequent itemsets since Apriori algorithm. Though existing method find all association rules, we must have a lot of process to analyze association rules because there are too many rules. In this paper, we propose a new data structure, called a Frequent Pattern Network (FPN), which represents items as vertices and 2-itemsets as edges of the network. In order to utilize FPN, We constitute FPN using item's frequency. And then we use a clustering method to group the vertices on the network into clusters so that the intracluster similarity is maximized and the intercluster similarity is minimized. We generate association rules based on clusters. Our experiments showed accuracy of clustering items on the network using confidence, correlation and edge weight similarity methods. And We generated association rules using clusters and compare traditional and our method. From the results, the confidence similarity had a strong influence than others on the frequent pattern network. And FPN had a flexibility to minimum support value.

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Visual Impairment Description for MPEG-21 Digital Item Adaptation (MPEG-21 디지털아이템적응변환을 위한 시각 장애 서술자에 관한 연구)

  • ;Truong Cong Thang
    • Journal of Broadcast Engineering
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    • 제8권4호
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    • pp.351-364
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    • 2003
  • In this paper, we propose visual Impairment descriptions for MPEG-21 digital item adaptation. The proposed visual impairment descriptions include low vision impairment and color vision deficiency. It is symptom-based description so that the description is systematic enough to sufficiently describe user's any kind of visual impairment characteristics and easy enough to describe for any user with visual impairment. In this paper, we performed some experiments with the proposed description in MPEG-21 digital item adaptation. The experiments showed that the proposed description Is effective to adapt visual resources In digital item for users with visual impairment and to give enhanced visual accessibility to them.

DK벤딩이 제시하는 중소기업 성공전략

  • 한국자동판매기공업협회
    • Vending industry
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    • 제3권1호통권9호
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    • pp.82-84
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    • 2004
  • 자판기 산업에 있어 중소기업들의 사업부진이 여간해 나아질 기미가 보이지 않는다. 무엇보다 중소기업을 어렵게 하는 것은 지속적으로 사업을 이끌어 갈 아이템이 많지 않다는 점이다. 몇몇 주력 아이템을 가진 업체를 제외하고는 악전고투 할 수밖에 없는 게 중소기업의 현실이다. 이러한 시장 여건 가운데 별다른 부침 없이 성장대로를 밝아 온 업체가 DK벤딩이다. 꾸준한 아이템 다변화로 새로운 도전을 주저치 않은 DK벤딩의 사업행보는 타중소기업들의 귀감이 되고 있다. 과연 DK벤딩이 제시하는 중소기업의 성공전략은 무엇인가.

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Clustering Method based on Genre Interest for Cold-Start Problem in Movie Recommendation (영화 추천 시스템의 초기 사용자 문제를 위한 장르 선호 기반의 클러스터링 기법)

  • You, Tithrottanak;Rosli, Ahmad Nurzid;Ha, Inay;Jo, Geun-Sik
    • Journal of Intelligence and Information Systems
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    • 제19권1호
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    • pp.57-77
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    • 2013
  • Social media has become one of the most popular media in web and mobile application. In 2011, social networks and blogs are still the top destination of online users, according to a study from Nielsen Company. In their studies, nearly 4 in 5active users visit social network and blog. Social Networks and Blogs sites rule Americans' Internet time, accounting to 23 percent of time spent online. Facebook is the main social network that the U.S internet users spend time more than the other social network services such as Yahoo, Google, AOL Media Network, Twitter, Linked In and so on. In recent trend, most of the companies promote their products in the Facebook by creating the "Facebook Page" that refers to specific product. The "Like" option allows user to subscribed and received updates their interested on from the page. The film makers which produce a lot of films around the world also take part to market and promote their films by exploiting the advantages of using the "Facebook Page". In addition, a great number of streaming service providers allows users to subscribe their service to watch and enjoy movies and TV program. They can instantly watch movies and TV program over the internet to PCs, Macs and TVs. Netflix alone as the world's leading subscription service have more than 30 million streaming members in the United States, Latin America, the United Kingdom and the Nordics. As the matter of facts, a million of movies and TV program with different of genres are offered to the subscriber. In contrast, users need spend a lot time to find the right movies which are related to their interest genre. Recent years there are many researchers who have been propose a method to improve prediction the rating or preference that would give the most related items such as books, music or movies to the garget user or the group of users that have the same interest in the particular items. One of the most popular methods to build recommendation system is traditional Collaborative Filtering (CF). The method compute the similarity of the target user and other users, which then are cluster in the same interest on items according which items that users have been rated. The method then predicts other items from the same group of users to recommend to a group of users. Moreover, There are many items that need to study for suggesting to users such as books, music, movies, news, videos and so on. However, in this paper we only focus on movie as item to recommend to users. In addition, there are many challenges for CF task. Firstly, the "sparsity problem"; it occurs when user information preference is not enough. The recommendation accuracies result is lower compared to the neighbor who composed with a large amount of ratings. The second problem is "cold-start problem"; it occurs whenever new users or items are added into the system, which each has norating or a few rating. For instance, no personalized predictions can be made for a new user without any ratings on the record. In this research we propose a clustering method according to the users' genre interest extracted from social network service (SNS) and user's movies rating information system to solve the "cold-start problem." Our proposed method will clusters the target user together with the other users by combining the user genre interest and the rating information. It is important to realize a huge amount of interesting and useful user's information from Facebook Graph, we can extract information from the "Facebook Page" which "Like" by them. Moreover, we use the Internet Movie Database(IMDb) as the main dataset. The IMDbis online databases that consist of a large amount of information related to movies, TV programs and including actors. This dataset not only used to provide movie information in our Movie Rating Systems, but also as resources to provide movie genre information which extracted from the "Facebook Page". Formerly, the user must login with their Facebook account to login to the Movie Rating System, at the same time our system will collect the genre interest from the "Facebook Page". We conduct many experiments with other methods to see how our method performs and we also compare to the other methods. First, we compared our proposed method in the case of the normal recommendation to see how our system improves the recommendation result. Then we experiment method in case of cold-start problem. Our experiment show that our method is outperform than the other methods. In these two cases of our experimentation, we see that our proposed method produces better result in case both cases.

Design Algorithm of Location based Recommendation System by Vector Analysis (위치기반 추천 시스템의 벡터 분석에 의한 알고리즘 설계)

  • Bae Keesung;Suh Songlee;Suk Minsoo
    • Proceedings of the Korea Information Processing Society Conference
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    • 한국정보처리학회 2004년도 추계학술발표논문집(상)
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    • pp.753-756
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    • 2004
  • 유비쿼터스 컴퓨팅 환경에서 추천시스템은 무수히 많은 정보들에 대하여 사람들이 적절한 선택을 할 수 있도록 도와준다. 사용자에게 필요한 정보를 찾아주고, 정보들의 우선순위를 결정해주는 추천시스템에 있어서 사용자의 위치는 보다 가치있는 정보를 제공할 수 있는 도구가 된다. 위치기반 추천시스템은 사용자가 아이템들로부터 얼마나 멀리 떨어져있는가를 고려하여 상위 리스트들을 제공할 수 있어야 한다. 하지만 일반적인 추천시스템에서 주로 사용되고 있는 기존의 사용자 기반 협업필터링 기법은 사용자의 자발적인 정보 입력에 의존함으로써 일정한 수의 사용자 정보가 축적되어 있지 않으면 정확한 추천이 불가능한 단점이 있다. 본 논문에서는 아이템에 기반한 협업 필터링 기법을 확률적으로 분석하고, 아이템의 위치에따라 랭킹을 부여하는 방법과 사용자의 위치정보를 추천알고리즘에 적용시켜 보다 정확하고 효율적인 추천방법을 제안하였다.

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Attack Detection in Recommender Systems Using a Rating Stream Trend Analysis (평가 스트림 추세 분석을 이용한 추천 시스템의 공격 탐지)

  • Kim, Yong-Uk;Kim, Jun-Tae
    • Journal of Internet Computing and Services
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    • 제12권2호
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    • pp.85-101
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    • 2011
  • The recommender system analyzes users' preference and predicts the users' preference to items in order to recommend various items such as book, movie and music for the users. The collaborative filtering method is used most widely in the recommender system. The method uses rating information of similar users when recommending items for the target users. Performance of the collaborative filtering-based recommendation is lowered when attacker maliciously manipulates the rating information on items. This kind of malicious act on a recommender system is called 'Recommendation Attack'. When the evaluation data that are in continuous change are analyzed in the perspective of data stream, it is possible to predict attack on the recommender system. In this paper, we will suggest the method to detect attack on the recommender system by using the stream trend of the item evaluation in the collaborative filtering-based recommender system. Since the information on item evaluation included in the evaluation data tends to change frequently according to passage of time, the measurement of changes in item evaluation in a fixed period of time can enable detection of attack on the recommender system. The method suggested in this paper is to compare the evaluation stream that is entered continuously with the normal stream trend in the test cycle for attack detection with a view to detecting the abnormal stream trend. The proposed method can enhance operability of the recommender system and re-usability of the evaluation data. The effectiveness of the method was verified in various experiments.

Analysis of Interaction Items in the Virtual Reality Game Interface (가상현실 게임 인터페이스의 상호작용 아이템 비교분석에 관한 연구)

  • Kang, Ho-Seong;Kim, Jung-Yoon
    • Journal of the Korean Society for Computer Game
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    • 제31권4호
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    • pp.185-195
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    • 2018
  • As virtual reality technology has gained popularity from people, various contents have appeared. Virtual reality game making good use of virtual reality device has received lots of attention from users and market. A number of virtual reality games have been developed. Virtual reality game allows users to feel presence and flow to be maximized through virtual reality device. A user can interact with several items through interface of device in display environment of virtual reality. This study was find a way to arouse an interest and induce users to be immersed in virtual reality game by maximizing above mentioned characteristics. This study was analyze interaction items in popular virtual reality game and interface design methods before presenting design methods. This study was make a comparative analysis of interface design methods centering on virtual reality game cases and examine a link between interface and interaction items. Through this study, it is expected that this will be a prior study that will be the basis for designing interfaces for virtual reality games that are more presence.

Hansel and Gretel : GFG Detection Scheme Based on In-Game Item Transactions (헨젤과 그레텔 : 게임 내 아이템 거래를 기반으로 한 GFG 탐지 방안)

  • Lee, Gyung Min;Kim, Huy Kang
    • Journal of the Korea Institute of Information Security & Cryptology
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    • 제28권6호
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    • pp.1415-1425
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    • 2018
  • MMORPG genre is based on the belief that all users in virtual world are equal. All users are able to obtain the corresponding wealth or status as they strive under the same resource, time. However, game bot is the main factor for harming this fair competition, causing benign gamers to feel a relative deprivation and deviate from the game. Game bots mainly form GFG(Gold Farming Group), which collects the goods in the game indiscriminately and adversely affects the economic system of the game. A general game bot detection algorithm is useful for detecting each bot, but it only covers few portions of GFG, not the whole, so it needs a wider range of detecting method. In this paper, we propose a method of detecting GFG based on items used in MMORPG genre. Several items that are mainly traded in the game were selected and the flows of those items were represented by a network. We Identified the characteristics of exchanging items of GFG bots and can identify the GFG's item trade network with real datasets from one of the popular online games.