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Generating semantic networks to the PubMed

Librelotto, Giovani Rubert; Martins, Mirkos; Machado, Henrique Tamiosso; Vizzotto, Juliana; Ramalho, José Carlos; Henriques, Pedro Rangel
Fonte: Universidade do Minho Publicador: Universidade do Minho
Tipo: Conferência ou Objeto de Conferência
Publicado em 14/02/2008 ENG
Relevância na Pesquisa
56.14%
This paper presents a topic map approach to PubMed in order to create a knowledge representation for this information system. PubMed is a free search engine that gives very full coverage of the related biomedical sciences. With more than 17 millions of citations since 1865, PubMed users have several problems to find the papers desired. So, it is necessary to organize these concepts in a semantic network. To achieve this objective, we use the Metamorphosis system, choosing the keywords from MeSH ontology. This way, we obtain an ontological index for PubMed, making easier to find specific papers.

The UMLS® Semantic Network and the Semantic Web

Kashyap, Vipul
Fonte: American Medical Informatics Association Publicador: American Medical Informatics Association
Tipo: Artigo de Revista Científica
Publicado em //2003 EN
Relevância na Pesquisa
46.38%
The Unified Medical Language System® (UMLS®) , an extensive source of biomedical knowledge developed and maintained by the US National Library of Medicine (NLM) is being currently used in a wide variety of biomedical applications. The Semantic Network, a component of the UMLS is a structured description of core biomedical knowledge consisting of well defined semantic types and relationships between them. We investigate the expressiveness of DAML+OIL, a markup language proposed for ontologies on the Semantic Web, for representing the knowledge contained in the Semantic Network. Requirements specific to the Semantic Network, such as polymorphic relationships and blocking relationship inheritance are discussed and approaches to represent these in DAML+OIL are presented. Finally, conclusions are presented along with a discussion of ongoing and future work.

Representing genomic knowledge in the UMLS semantic network.

Yu, H.; Friedman, C.; Rhzetsky, A.; Kra, P.
Fonte: American Medical Informatics Association Publicador: American Medical Informatics Association
Tipo: Artigo de Revista Científica
Publicado em //1999 EN
Relevância na Pesquisa
46.36%
Genomics research has a significant impact on the understanding and treatment of human hereditary diseases, and biomedical literature concerning the genome project is becoming more and more important for clinicians. The Unified Medical Language System (UMLS) is designed to facilitate the retrieval and integration of information from multiple-readable biomedical information resources. This paper describes our efforts to integrate concepts important to genomics research with the UMLS semantic network. We found that the UMLS contains over 30 semantic types and most of the semantic relations that are essential for representing the underlying genomic knowledge. In addition, we observed that the organization of the network was appropriate for representing the hierarchical organization of the concepts. Because some of the concepts critical to the genomic domain were found to be missing, we propose to extend the network by adding six new semantic types and sixteen new semantic relations.

Mapping the UMLS Semantic Network into general ontologies.

Burgun, A.; Bodenreider, O.
Fonte: American Medical Informatics Association Publicador: American Medical Informatics Association
Tipo: Artigo de Revista Científica
Publicado em //2001 EN
Relevância na Pesquisa
46.23%
In this study, we analyzed the compatibility between an ontology of the biomedical domain (the UMLS Semantic Network) and two other ontologies: the Upper Cyc Ontology (UCO) and WordNet. 1) We manually mapped UMLS Semantic Types to UCO. One fifth of the UMLS Semantic Types had exact mapping to UCO types. UCO provides generic concepts and a structure that relies on a larger number of categories, despite its lack of depth in the biomedical domain. 2) We compared semantic classes in the UMLS and WordNet. 2% of the UMLS concepts from the Health Disorder class were present in WordNet, and compatibility between classes was 48%. WordNet, as a general language-oriented ontology is a source of lay knowledge, particularly important for consumer health applications.

An fMRI examination of the effects of acoustic-phonetic and lexical competition on access to the lexical-semantic network

Minicucci, Domenic; Guediche, Sara; Blumstein, Sheila E.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
46.35%
The current study explored how factors of acoustic-phonetic and lexical competition affect access to the lexical-semantic network during spoken word recognition. An auditory semantic priming lexical decision task was presented to subjects while in the MR scanner. Prime-target pairs consisted of prime words with the initial voiceless stop consonants /p/, /t/, and /k/ followed by word and nonword targets. To examine the neural consequences of lexical and sound structure competition, primes either had voiced minimal pair competitors or they did not, and they were either acoustically modified to be poorer exemplars of the voiceless phonetic category or not. Neural activation associated with semantic priming (Unrelated–Related conditions) revealed a bilateral fronto-temporo-parietal network. Within this network, clusters in the left insula/inferior frontal gyrus (IFG), left superior temporal gyrus (STG), and left posterior middle temporal gyrus (pMTG) showed sensitivity to lexical competition. The pMTG also demonstrated sensitivity to acoustic modification, and the insula/IFG showed an interaction between lexical competition and acoustic modification. These findings suggest the posterior lexical-semantic network is modulated by both acoustic-phonetic and lexical structure...

Simulating a Semantic Network in LMS

Koton, Phyllis A.
Fonte: MIT Artificial Intelligence Laboratory Publicador: MIT Artificial Intelligence Laboratory
Tipo: Trabalho em Andamento
EN_US
Relevância na Pesquisa
46.26%
A semantic network is a collection of nodes and the links between them. The nodes represent concepts, functions and entities, and the links represent relationships between varoius nodes. Any semantic network must be supplied with a language of conventions for representing knowledge as nodes and links in the network, so that storage and retrieval of knowledge can be carried out efficiently. This thesis examines two approaches to the problem of representing real-world knowledge in a computer: one designed for use on serial computers, the other design to run on a parallel network machine. The two formalisms are shown to be nearly identical, and a simulation of the parallel language in the serial language is given.; Submitted to the Department of Electrical Engineering and Computer Science on January 1, 1980 in partial fulfillment of the requirements for the Degree of Bachelor of Science.; MIT Artificial Intelligence Laboratory

Conhecimento sobre energia eólica: um estudo exploratório a partir das redes semânticas naturais de estudantes da cidade de Natal; Knowledge about wind energy: an exploratory study taking into account natural semantic networks of students from Natal-RN

Pessoa, Viviany Silva
Fonte: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Psicologia; Psicologia, Sociedade e Qualidade de Vida Publicador: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Psicologia; Psicologia, Sociedade e Qualidade de Vida
Tipo: Dissertação Formato: application/pdf
POR
Relevância na Pesquisa
46.32%
The human being has a fundamental role in issues concerning scarcity of energy resources as well as in the success of technologies which favor the use of renewable sources, such as wind energy. But what does wind energy mean for people? What are the psychological meanings concerning this term? Aiming to answer these questions, the general objective of this dissertation was to identify and to analyze the knowledge about wind energy taking into account a network of psychological meanings. One hundred and ninety one (191) university students from Natal-RN participated in the study, being male the majority (53%); aged between 17 and 51 years old (M=23.3 years; SD=5.7). Participants responded to self reports using the Natural Semantic Networks (NSW) technique, as well as to several sociodemographic questions. The results showed a consistent, positive and useful general semantic network. In this semantic network, knowledge about wind energy was represented by words that correspond to the appeal of (pro) environmental stance (e.g., clean and nature), that evinced both the technological aspect (e.g., force) and the economic aspect (e.g., economy). Results from different groups were also analyzed. The first set of groups (non-environemental and environmental) was divided considering the course (e.g....

Better explanations of lexical and semantic cognition using networks derived from continued rather than single-word associations

de Deyne, S.; Navarro, D.; Storms, G.
Fonte: Psychonomic Soc Inc Publicador: Psychonomic Soc Inc
Tipo: Artigo de Revista Científica
Publicado em //2013 EN
Relevância na Pesquisa
56.4%
In this article, we describe the most extensive set of word associations collected to date. The database contains over 12,000 cue words for which more than 70,000 participants generated three responses in a multiple-response free association task. The goal of this study was (1) to create a semantic network that covers a large part of the human lexicon, (2) to investigate the implications of a multiple-response procedure by deriving a weighted directed network, and (3) to show how measures of centrality and relatedness derived from this network predict both lexical access in a lexical decision task and semantic relatedness in similarity judgment tasks. First, our results show that the multiple-response procedure results in a more heterogeneous set of responses, which lead to better predictions of lexical access and semantic relatedness than do single-response procedures. Second, the directed nature of the network leads to a decomposition of centrality that primarily depends on the number of incoming links or in-degree of each node, rather than its set size or number of outgoing links. Both studies indicate that adequate representation formats and sufficiently rich data derived from word associations represent a valuable type of information in both lexical and semantic processing.; Simon De Deyne & Daniel J. Navarro & Gert Storms

Relationship Structures and Semantic Type Assignments of the UMLS Enriched Semantic Network

Zhang, Li; Halper, Michael; Perl, Yehoshua; Geller, James; Cimino, James J.
Fonte: American Medical Informatics Association Publicador: American Medical Informatics Association
Tipo: Artigo de Revista Científica
Publicado em //2005 EN
Relevância na Pesquisa
46.34%
Objective: The Enriched Semantic Network (ESN) was introduced as an extension of the Unified Medical Language System (UMLS) Semantic Network (SN). Its multiple subsumption configuration and concomitant multiple inheritance make the ESN's relationship structures and semantic type assignments different from those of the SN. A technique for deriving the relationship structures of the ESN's semantic types and an automated technique for deriving the ESN's semantic type assignments from those of the SN are presented.

The UMLS Semantic Network

McCray, Alexa T.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 08/11/1989 EN
Relevância na Pesquisa
46.23%
The UMLS network of semantic types is one component of NLM's evolving Unified Medical Language System. This paper discusses the role of the semantic network in the overall system, then describes the evolution and current status of the network, and, finally, concludes with a discussion of plans for further development.

Enriching the structure of the UMLS semantic network.

Zhang, Li; Perl, Yehoshua; Halper, Michael H.; Geller, James; Cimino, James J.
Fonte: American Medical Informatics Association Publicador: American Medical Informatics Association
Tipo: Artigo de Revista Científica
Publicado em //2002 EN
Relevância na Pesquisa
46.39%
The Unified Medical Language System's (UMLS's) Semantic Network (SN)---consisting of a network of semantic types---has a two-tree structure, where each semantic type has at most one parent semantic type. This arrangement is restrictive because some semantic types are, by their definition, specializations of several parents. As a proposed enhancement to the SN, its semantic types have previously been partitioned into groups, each of which contains semantic types of some specific area. However, some groups of this proposed partition contain forest (i.e., multiple-tree) structures or even isolated semantic types. Both situations imply a disconnected internal structure. Connectivity is actually one way to assess the proposed "semantic validity" principle for partitions. It is a desired, although not required, property. In this paper, we introduce a methodology for identifying "missing" IS-A links and adding them to the SN. This process transforms the SN into a Directed Acyclic Graph (DAG) structure, with semantic types permitted to have multiple parents. A result of our methodology is the transformation of the proposed SN partition into groups satisfying the connectivity property.

General-Purpose Computing on a Semantic Network Substrate

Rodriguez, Marko A.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
46.29%
This article presents a model of general-purpose computing on a semantic network substrate. The concepts presented are applicable to any semantic network representation. However, due to the standards and technological infrastructure devoted to the Semantic Web effort, this article is presented from this point of view. In the proposed model of computing, the application programming interface, the run-time program, and the state of the computing virtual machine are all represented in the Resource Description Framework (RDF). The implementation of the concepts presented provides a practical computing paradigm that leverages the highly-distributed and standardized representational-layer of the Semantic Web.

Transforming the World Wide Web into a Complexity-Based Semantic Network

Marko, M.; Porter, M. A.; Probst, A.; Gershenson, C.; Das, A.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
46.23%
The aim of this paper is to introduce the idea of the Semantic Web to the Complexity community and set a basic ground for a project resulting in creation of Internet-based semantic network of Complexity-related information providers. Implementation of the Semantic Web technology would be of mutual benefit to both the participants and users and will confirm self-referencing power of the community to apply the products of its own research to itself. We first explain the logic of the transition and discuss important notions associated with the Semantic Web technology. We then present a brief outline of the project milestones.; Comment: 6 pages, a manuscript for the ICCS 2002

Modeling Computations in a Semantic Network

Rodriguez, Marko A.; Bollen, Johan
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 31/05/2007
Relevância na Pesquisa
46.39%
Semantic network research has seen a resurgence from its early history in the cognitive sciences with the inception of the Semantic Web initiative. The Semantic Web effort has brought forth an array of technologies that support the encoding, storage, and querying of the semantic network data structure at the world stage. Currently, the popular conception of the Semantic Web is that of a data modeling medium where real and conceptual entities are related in semantically meaningful ways. However, new models have emerged that explicitly encode procedural information within the semantic network substrate. With these new technologies, the Semantic Web has evolved from a data modeling medium to a computational medium. This article provides a classification of existing computational modeling efforts and the requirements of supporting technologies that will aid in the further growth of this burgeoning domain.; Comment: project website: http://neno.lanl.gov

Incorporating fishing community perceptions into fisheries management through semantic network analysis: Case studies of the U.S. Virgin Islands and Fiji

Maize, Kristen
Fonte: Universidade Duke Publicador: Universidade Duke
Tipo: Masters' project
Publicado em 25/04/2012
Relevância na Pesquisa
66.25%
Historical review illustrates that humans have had a profound impact on the coastal marine ecosystem, with overfishing eclipsing all other human disturbances. Recognition of this anthropogenic impact and attempts at managing fisheries over time highlight the need to manage the behaviors of people, not just fish, when managing fisheries. This study explores the application of a software program to present qualitative data in a format more in line with a management system largely driven by quantitative analysis. Utilizing the case studies of reef fish spawning aggregation management in the U.S. Virgin Islands and Fiji, this research addresses the need to represent and incorporate fishing community perspectives into fisheries management. Through in-depth interviews and the application of semantic network analysis, qualitative open-ended responses to questions related to: 1) changes in marine resources, 2) reef fish spawning aggregations, and 3) local fisheries management are presented as semantic networks. These networks provide snapshots identifying the collective knowledge, feelings, and perspectives of the fishing communities in these two locations with different community and fisheries management structures. The identification and representation of shared resource management themes can aide managers in identifying appropriate management strategies given the specific social context.

Neural changes associated with semantic processing in healthy aging despite intact behavioral performance

Lacombe, Jacinthe; Jolicoeur, Pierre; Grimault, Stephan; Pineault, Jessica; Joubert, Sven
Fonte: Université de Montréal Publicador: Université de Montréal
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
46.31%
Semantic memory recruits an extensive neural network including the left inferior prefrontal cortex (IPC) and the left temporoparietal region, which are involved in semantic control processes, as well as the anterior temporal lobe region (ATL) which is considered to be involved in processing semantic information at a central level. However, little is known about the underlying neuronal integrity of the semantic network in normal aging. Young and older healthy adults carried out a semantic judgment task while their cortical activity was recorded using magnetoencephalography (MEG). Despite equivalent behavioral performance, young adults activated the left IPC to a greater extent than older adults, while the latter group recruited the temporoparietal region bilaterally and the left ATL to a greater extent than younger adults. Results indicate that significant neuronal changes occur in normal aging, mainly in regions underlying semantic control processes, despite an apparent stability in performance at the behavioral level.

OBJECT ORIENTED ANALYSIS AND SEMANTIC NETWORK FOR HIGH RESOLUTION IMAGE CLASSIFICATION

ANTUNES, ALZIR FELIPPE B.; LINGNAU, CHRISTEL; CENTENO, JORGE ANTONIO SILVA
Fonte: Universidade Federal do Paraná-UFPR Publicador: Universidade Federal do Paraná-UFPR
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; Artigo Avaliado pelos Pares Formato: application/pdf
Publicado em 16/11/2004 POR
Relevância na Pesquisa
46.25%
Este artigo apresenta a classificação digital de imagem de alta resolução baseada em orientação a objeto. Os objetos da imagem (Ikonos, multiespectral) são oriundos de segmentação multi-resolução que permite a obtenção de diferentes níveis de segmentação. A segmentação em diferentes camadas pode apoiar uma estrutura hierárquica de segmentos, onde uma rede semântica pode ser introduzida. A rede semântica é baseada no processo cognitivo do usuário. O conhecimento pode ser explicitado por meio de regras fuzzy considerando descritores de forma e textura dos objetos, bem como as suas relações topológicas - entre objetos e subobjetos. São testados diferentes métodos de classificação dentro da rede semântica tais como seletivo e mudança de contexto. A área teste é uma zona agrícola, no Município de Nova Esperança-PR, onde se propôs mapear a mata ciliar ao longo do Rio Porecatú. Abstract This work presents a high resolution image classification based on object oriented. The objects are derived from multiresolution segmentation ( from multispectral image, Ikonos). It allows a creation of different levels of segments supporting a hierarchical structure, generating spatial relations between objects and sub-objects. This hierarchy is the bedding for the semantic network. The knowledge is the semantic basis. The classification is based on fuzzy rules by means of descriptors such as form...

Denotation and connotations of biotechnology in Korean public opinion: a semantic network approach

Kim, Leo Dhohoon
Fonte: London School of Economics and Political Science Thesis Publicador: London School of Economics and Political Science Thesis
Tipo: Thesis; NonPeerReviewed Formato: text
Publicado em /10/2014 EN
Relevância na Pesquisa
46.29%
This thesis tests how the frames and social representations of human embryonic stem cell research in South Korea could be visualized and measured by semantic network analysis. The contents of published articles take an eclectic approach to integrate sociological, social psychological, and semiological concepts and perspectives. By combining ethnographical and sociological approaches with applied semantic network analysis, concepts usually inferred and narrated by the researcher gain more vivid and intuitive visual representation along with mathematical substantiation. The methodology especially proposes indices to measure the most salient concepts that represent denotation and connotation out of the text corpus, and the ways to categorize themes more efficiently. The study concludes that the failure to establish a sustainable public relation and deliberative atmosphere regarding human embryonic stem cell research in South Korea is mainly due to polarized framings of opinion leading newspapers, progressive side’s incompetence to present an alternative agenda to economic development and suppressed discourses of lay people who strive for more transparent and just (scientific) governance. The semantic network represents the diverging core concepts of newspapers and people’s concealed motives in supporting the disgraced Korean scientist Woo-Suk Hwang and urges readers to deliberate on the scientific issue from a different perspective.

Inferring Relations and Annotations in Semantic Network: Application to Radiology

Ramadier,Lionel; Zarrouk,Manel; Lafourcade,Mathieu; Micheau,Antoine
Fonte: Centro de Investigación en computación, IPN Publicador: Centro de Investigación en computación, IPN
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2014 EN
Relevância na Pesquisa
56.33%
Domain-specific ontologies are invaluable despite many challenges associated with their development. In most cases, domain knowledge bases are built with very limited scope without considering the benefits of plunging domain knowledge to a general ontology. Furthermore, most existing resources lack meta-information about association strength (weights) and annotations (frequency information like frequent, rare, etc. or relevance information like pertinent or irrelevant). In this paper, we present a semantic resource for radiology built over an existing general semantic lexical network (JeuxDeMots). This network combines weight and annotations on typed relations between terms and concepts. Some inference mechanisms are applied to the network to improve its quality and coverage. We extend this mechanism to relation annotation. We describe how annotations are handled and how they improve the network by imposing new constraints especially those founded on medical knowledge.

Inference and Reconciliation in a Crowdsourced Lexical-Semantic Network

Zarrouk,Manel; Lafourcade,Mathieu; Joubert,Alain
Fonte: Centro de Investigación en computación, IPN Publicador: Centro de Investigación en computación, IPN
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2013 EN
Relevância na Pesquisa
46.29%
Lexical-semantic network construction and validation is a major issue in NLP. No matter the construction strategies used, automatically inferring new relations from already existing ones is a way to improve the global quality of the resource by densifying the network. In this context, the purpose of an inference engine is to formulate new conclusions (i.e. relations between terms) from already existing premises (also relations) on the network. In this paper we devise an inference engine for the JeuxDeMots lexical network which contains terms and typed relations between terms. In the JeuxDeMots project, the lexical network is constructed with the help of a game with a purpose and thousands of players. Polysemous terms may be refined in several senses (bank may be a bank-financial institution or a bank-river) but as the network is indefinitely under construction (in the context of a Never Ending Learning approach) some senses may be missing. The approach we propose is based on the triangulation method implementing semantic transitivity with a blocking mechanism for avoiding proposing dubious new relations. Inferred relations are proposed to contributors to be validated. In case of invalidation, a reconciliation strategy is undertaken to identify the cause of the wrong inference: an exception...