• Title/Summary/Keyword: Boolean

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A Study on Geometrical Glue Operation between Non-manifold Models (비다양체 모델간의 기하학적 접합 연산에 관한 연구)

  • Park, Sang-Ho
    • Journal of the Korea Computer Graphics Society
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    • v.4 no.1
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    • pp.11-19
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    • 1998
  • Non-manifold topological operations such as Euler and Boolean operations provide a versatile environment for modeling domains. The implementation of these operations raises geometrical issues that need to be addressed to ensure the topological validity of the underlying model, and they uses the glue operation which provides a basic method to modify the topology of non-manifold models when vertices, edges and faces are contacting each other. Topological information such as adjacency relationships should be inferred when gluing non-manifold models. Two methods of reasoning can be employed to find the topological information : topological reasoning and geometrical reasoning. The topological method can infer the adjacency relationships by using stored topological information. On the other hand, the geometrical method can find topological ambiguities by considering the geometrical shape at the local area of gluing when the topological relations were not stored. This paper describes the geometrical reasoning method.

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A Document Ranking Method by Document Clustering Using Bayesian SoM and Botstrap (베이지안 SOM과 붓스트랩을 이용한 문서 군집화에 의한 문서 순위조정)

  • Choe, Jun-Hyeok;Jeon, Seong-Hae;Lee, Jeong-Hyeon
    • The Transactions of the Korea Information Processing Society
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    • v.7 no.7
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    • pp.2108-2115
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    • 2000
  • The conventional Boolean retrieval systems based on vector spae model can provide the results of retrieval fast, they can't reflect exactly user's retrieval purpose including semantic information. Consequently, the results of retrieval process are very different from those users expected. This fact forces users to waste much time for finding expected documents among retrieved documents. In his paper, we designed a bayesian SOM(Self-Organizing feature Maps) in combination with bayesian statistical method and Kohonen network as a kind of unsupervised learning, then perform classifying documents depending on the semantic similarity to user query in real time. If it is difficult to observe statistical characteristics as there are less than 30 documents for clustering, the number of documents must be increased to at least 50. Also, to give high rank to the documents which is most similar to user query semantically among generalized classifications for generalized clusters, we find the similarity by means of Kohonen centroid of each document classification and adjust the secondary rank depending on the similarity.

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Design of Random Binary Sequence Generator using the Chaotic Map (혼돈맵을 사용한 난수성 2진 순서발생기의 설계)

  • Park, Kwang-Hyeon;Baek, Seung-Jae
    • The Journal of the Korea Contents Association
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    • v.8 no.7
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    • pp.53-57
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    • 2008
  • The discretized saw-tooth map with the 16-bit finite precision which is one of the 1-dimensional chaotic maps is designed, and the circuit of chaotic binary sequence generator using the discretized saw-tooth map is presented also in this brief. The real implementation of designed chaotic map is accomplished by connecting the input and output lines exactly according to the simplified Boolean functions of output variables obtained from truth table which is discretized. The random binary output sequences generated by mLFSR generator were used for the inputs of descretized saw-tooth map, and, by the descretized map, chaotic binary sequence which has more long period of 16 times minimally is generated as a results.

Sheet Modeling and Transformation of Sheet into Solid Based on Non-manifold Topological Representation (바다양체 위상 표현을 바탕으로 한 박판 형상 모델링 및 솔리드로의 변환)

  • Lee, S.H.;Lee, K.W.
    • Journal of the Korean Society for Precision Engineering
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    • v.13 no.7
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    • pp.100-114
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    • 1996
  • In order to create a solid model more efficiently for a plastic or sheet metal product with a thin and constant thickness, various methods have been proposed up to now. One of the most typical approaches is to create a sheet model initially and then transform it into a solid model automatically for a given thickness. The sheet model as well as the transitive model in sheet modeling procedure is a non-manifold model. However, the previous methods adopted the boundary representations for a solid model as their topological framework. Thus, it is difficult to represent the exact adjacency relationship between topological entities and to implement the topological operations for sheet modeling and the transformation procedure of a sheet into a solid. In this paper, we proposed a sheet modeling system based on a non-manifold topological representation which can represent solids, sheets, wireframes, and their mixture. A set of generalized Euler operators for non-manifold topology as well as the sheet modeling capabilities including adding, bending, and punching functions are provided for easy modeling of sheet objects, and they are perfomed interactively with a two dimensional curve editor. Once a sheet model is completed, it can be transformed into a solid automatically. The transformation procedure is composed of the offset functions and the Boolean operations of sheet models, and it is even more comprehensive and easier to be implemented than the precious methods.

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On Near Subtraction Semigroups (Near Subtraction Semigroups에 관한 연구)

  • Yon Yong-Ho;Kim Mi-Suk;Kim Mi-Hye
    • Proceedings of the Korea Contents Association Conference
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    • 2003.05a
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    • pp.406-410
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    • 2003
  • B. M. Schein([1]) considered systems of the form (${\Phi}$; ${\circ}$,-), where ${\Phi}$ is a set of functions closed under the composition "${\circ}$" of functions and the set theoretic subtraction "-". In this structure, (${\Phi}$; ${\circ}$) is a function semigroup and (${\Phi}$;-) is a subtraction algebra in the sense of [1]. He proved that every subtraction semigroup is isomorphic to a difference semigroup of invertible functions. Also this structure is closely related to the mathematical logic, Boolean algebra, Bck-algera, etc. In this paper, we define the near subtraction semigroup as a generalization of the subtraction semigroup, and define the notions of strong for it, and then we will search the general properties of this structure, the properties of ideals, and the application of it.

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Application of the Fuzzy Method to Improve GIS Geomorphological Method of Predicting Flood Vulnerable Area

  • Kim Su Jeong;Yom Jae-Hong;Lee Dong-Cheon
    • Proceedings of the KSRS Conference
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    • 2004.10a
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    • pp.264-267
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    • 2004
  • In identifying flood vulnerable areas, three methods are generally deployed: the geomorphology method which is based on topographic features; the past evidence method based on observed data of past actual floods; and, prediction of flood areas through hydrologic models. This study aims to improve the prediction model of the geomorphology method through the application of fuzzy method in GIS modeling. The generally used GIS method of superimposing thematic map layers assumes crisp boundaries of the layers, which results in either risk-averse solutions or risk-taking solutions. The introduction of fuzzy concepts to processing of evaluation criteria (DEM, slope, aspect) solves this problem. As the result of applying the fuzzy method to a test site in the west Nak-Dong river, similar flood vulnerable areas were predicted as when using the conventional Boolean criteria. The resulting map, however, showed varying degree of uncertainty of flooding in these areas. This extra information is deemed to be valuable in taking phased actions during flood response, leading to a more effective and timely decision-making.

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Boolean Formulation of Korean Natural Language Queries Using Syntactic Analysis (구문 분석에 기반한 자연어 질의로부터의 불리언 질의 생성)

  • Park, Mi-Hwa;Won, Hyung-Suk;Lee, Won-Il;Lee, Geun-Bae
    • Annual Conference on Human and Language Technology
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    • 1998.10c
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    • pp.73-80
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    • 1998
  • 본 연구는 자연어 질의의 형태 및 구문 정보를 바탕으로 불리언 질의를 생성하는데 그 목적을 둔다. 일반적으로 대부분의 상용정보검색시스템은 입력형식을 검색성능이 종은 불리언 형태로 하고 있으나, 일반 사용자는 자신이 원하는 정보를 불리언 형태로 표현하는데 익숙하지 않다. 그러므로 본 정보검색시스템은 자연어 질의를 기본 입력형태로 하여 사용자의 편의성을 높이고, 이 질의를 범주문법에 기반한 구문분석 결과에 의해 복합명사를 고려한 불리언 형태로 변환하여 검색을 수행함으로써 시스템의 검색 성능의 향상을 도모하였다. 정보검색 실험용 데이터 모음인 KTSET2.0으로 실험한 결과 본 논문에서 제안한 자연어 질의로부터 자동 생성된 불리언 질의의 검객성능이 KTSET2.0에서 제공하는 수동으로 추출한 불리언 질의보다 8% 더 우수한 성능을 보였고, 기존 자연어질의 시스템이 수용해온 방법인 형태소 분석을 거쳐 불용어를 제거한 후 Vector 모델을 적용하여 검색을 수행한 경우보다는 23% 더 나은 성능을 보였다.

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Chronic Infections of the Urinary Tract and Bladder Cancer Risk: a Systematic Review

  • Anderson-Otunu, Oghenetejiri;Akhtar, Saeed
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.8
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    • pp.3805-3807
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    • 2016
  • Literature on the relationship between recurrent urinary tract infections and urinary bladder carcinoma risk has been inconsistent. Therefore, we carried out this systematic review of observational studies to ascertain if there is any association between chronic urinary tract infection and urinary bladder carcinoma. A total of 10 databases were searched using Boolean: CINAHL, PUBMED, Google Scholar, Medline, Science Direct, SCIRUS, Cochrane, UK PubMed central, NHS evidence and WHO-website. The search yielded an initial hit of 3,518 articles and after screening and critical appraisal, seven studies were included for this review. Four articles reported an association between chronic urinary tract infections and bladder cancer while three concluded a weak or no association at least in one gender. Main findings in this review were that most of the studies reported an association between chronic urinary tract infections and bladder cancer risk. However, inferences about the causal association between chronic urinary tract infections and bladder cancer risk should be drawn cautiously considering the methodological limitations of case-control studies included in this review. Therefore, more empirical evidence is needed to determine the causal nature of relationships between chronic urinary tract infections and bladder cancer risk.

Targeting Algorithm for Personalized Message Syndication (개인 맞춤형 메시지 신디케이션을 위한 타겟팅 알고리즘)

  • Kim, Nam-Yun
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.12 no.3
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    • pp.43-49
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    • 2012
  • Personalized message syndication is an important process for maximizing the effect of mobile marketing. This paper proposes an algorithm for determining clients satisfying target conditions in real-time. The proxy server as an intermediate node stores client profiles (gender, age, location, etc) and their respective summaries into a database. When a company syndicates messages at run time, the proxy server maps target conditions expressed by boolean expressions to integer value and determines target clients by comparing target value with profile summary. Thus, this approach provides efficient personalized message syndication in very large systems with millions of clients because it can determine target clients in real-time and work with a traditional database easily.

A Study on Improving the Effectiveness of Information Retrieval Through P-norm, RF, LCAF

  • Kim, Young-cheon;Lee, Sung-joo
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.2 no.1
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    • pp.9-14
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    • 2002
  • Boolean retrieval is simple and elegant. However, since there is no provision for term weighting, no ranking of the answer set is generated. As a result, the size of the output might be too large or too small. Relevance feedback is the most popular query reformulation strategy. in a relevance feedback cycle, the user is presented with a list of the retrieved documents and, after examining them, marks those which are relevant. In practice, only the top 10(or 20) ranked documents need to be examined. The main idea consists of selecting important terms, or expressions, attached to the documents that have been identified as relevant by the user, and of enhancing the importance of these terms in a new query formulation. The expected effect is that the new query will be moved towards the relevant documents and away from the non-relevant ones. Local analysis techniques are interesting because they take advantage of the local context provided with the query. In this regard, they seem more appropriate than global analysis techniques. In a local strategy, the documents retrieved for a given query q are examined at query time to determine terms for query expansion. This is similar to a relevance feedback cycle but might be done without assistance from the user.