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Cataloguing of learning objects using social tagging

Amaral, Anderson Roque do; Zaina, Luciana A. M.; Rodrigues Junior, José Fernando
Fonte: Universidad de la República; Universidad Católica del Uruguay; Universidad ORT Uruguay; Universidad de Montevideo; Universidad de la Empresa; Montevideo Publicador: Universidad de la República; Universidad Católica del Uruguay; Universidad ORT Uruguay; Universidad de Montevideo; Universidad de la Empresa; Montevideo
Tipo: Conferência ou Objeto de Conferência
Português
Relevância na Pesquisa
36.83%
Social tagging has been recognized as an importante solution to the description of resources available on the Web. In the context of e-learning it is presented as an auxiliary mechanism to the composition of learning object metadata. This article aims to present the results of a study on the state of the art of works related to social tagging and learning objects, promoting a discussion about the main elements related to the concepts.

The use of social tagging to support the cataloguing of learning objects

Amaral, Anderson Roque do; Zaina, Luciana A. M.; Rodrigues Junior, José Fernando; Aguiar, Renan de; Barboza, Marcos Cavalcante
Fonte: Universidad Nacional de Educación a Distancia - UNED; Universidad Politécnica de Madrid - UPM; Institute of Electrical and Electronics Engineers - IEEE; American Society for Engineering Education - ASEE; Madrid Publicador: Universidad Nacional de Educación a Distancia - UNED; Universidad Politécnica de Madrid - UPM; Institute of Electrical and Electronics Engineers - IEEE; American Society for Engineering Education - ASEE; Madrid
Tipo: Conferência ou Objeto de Conferência
Português
Relevância na Pesquisa
37.1%
Social networks have become the main media for information dissemination in the so-called Web 2.0. The core of these networks is social tagging, the act of annotating what users see in their social space. In the education domain, social tagging is potentially a useful resource to improve the organization (cataloguing) of large repositories of learning objects. To the present moment, however, many questions are open about social tagging in e-learning. In this work, hence, we proceed to answer three questions: (1) Can social tagging successfully catalog e-learning objects? (2) How do students behave according to Körner’s classification: categorizers or describers? and (3) Does social tagging converge to a well-defined descriptive vocabular of tags? We performed a large experiment with 336 technician students that marked 218 electronic learning objects for about 4,985 times. Our results show that social tagging is a promising practice for e-learning; however some issues must be addressed to prevent an excessive number of categorizer students and, also, a premature convergence of the vocabulary of tags. Our conclusions are specific for the setting of our experiment, but we generalize them as much as possible suggesting guidelines of how to use social tagging in e-learning.

Social tagging and Dublin Core : a preliminary proposal for an application profile fo DC social tagging

Catarino, Maria Elisabete; Baptista, Ana Alice
Fonte: Universidade do Minho Publicador: Universidade do Minho
Tipo: Conferência ou Objeto de Conferência
Publicado em /06/2008 Português
Relevância na Pesquisa
36.83%
The Web 2.0 maximizes the Internet concept of encouraging its users to cooperate effectively for the offer of virtual services and content organization. Among the various potentialities of the Web 2.0, folksonomy appears as a result of the free assignment of tags to the Web’s resources by their users/ readers. Despite tags describe the Web’s resources, generally they are not integrated in the metadata. In order for them to be intelligible by machines and therefore used in the Semantic Web context, they have to be automatically allocated to specific metadata elements. There are many metadata formats. The focus of this investigation will be the Dublin Core Metadata Terms (DCTerms) that is a widely used set of properties for the description of electronic resources. A subset of DCTerms, the Dublin Core Metadata Element Set (DCMES), has been adopted by the majority of Institutional Repositories’ platforms as a way to promote interoperability. We propose a research that intends to identify elements of the metadata originated from folksonomies and propose an application profile for DC Social Tagging. That will allow tags to be conveniently processed by interoperability protocols, particularly the Open Archives Initiative – Protocol for Metadata Harvesting (OAI-PMH). This paper will present the results of the pilot study developed in the beginning of the research as well as the metadata elements preliminarily defined.; Capes/MEC - Brasil.; Fundação para a Ciência e Tecnologia (FCT).

Contributos para a eficácia do clustering usando o tagging social

Cunha, Elisabete Ferraz da
Fonte: Universidade de Aveiro Publicador: Universidade de Aveiro
Tipo: Tese de Doutorado
Português
Relevância na Pesquisa
36.83%
Nos últimos anos temos vindo a assistir a uma mudança na forma como a informação é disponibilizada online. O surgimento da web para todos possibilitou a fácil edição, disponibilização e partilha da informação gerando um considerável aumento da mesma. Rapidamente surgiram sistemas que permitem a coleção e partilha dessa informação, que para além de possibilitarem a coleção dos recursos também permitem que os utilizadores a descrevam utilizando tags ou comentários. A organização automática dessa informação é um dos maiores desafios no contexto da web atual. Apesar de existirem vários algoritmos de clustering, o compromisso entre a eficácia (formação de grupos que fazem sentido) e a eficiência (execução em tempo aceitável) é difícil de encontrar. Neste sentido, esta investigação tem por problemática aferir se um sistema de agrupamento automático de documentos, melhora a sua eficácia quando se integra um sistema de classificação social. Analisámos e discutimos dois métodos baseados no algoritmo k-means para o clustering de documentos e que possibilitam a integração do tagging social nesse processo. O primeiro permite a integração das tags diretamente no Vector Space Model e o segundo propõe a integração das tags para a seleção das sementes iniciais. O primeiro método permite que as tags sejam pesadas em função da sua ocorrência no documento através do parâmetro Social Slider. Este método foi criado tendo por base um modelo de predição que sugere que...

POS-Tagging usando pesquisa local

Laranjinho, João; Rodrigues, Irene; Ferreira, Lígia
Fonte: Escola de Ciências e Tecnologia da Universidade de Évora Publicador: Escola de Ciências e Tecnologia da Universidade de Évora
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
36.7%
Neste artigo apresenta-se um sistema de part-of-speech tagging, independente do domínio, para etiquetação gramatical de texto para o Português e Inglês. O etiquetador usa informação morfo-sintáctica que vem de um dicionário local que completa a sua informação recorrendo a dicionários disponíveis na rede como o da Priberam e do LookWayUP. Este etiquetador é baseado numa função heurística que é usada na optimização dos seus parâmetros e posterior etiquetação de texto. Na optimização dos parâmetros da função heurística são usadas algumas das técnicas de pesquisa local para reduzir o espaço de pesquisa. Na avaliação do sistema usaram-se dois textos do corpora Reuters: testa (na fase treino) e testb (na fase de teste).

Learning techniques for automatic email message tagging

Tam, Tony
Fonte: Instituto Politécnico de Lisboa Publicador: Instituto Politécnico de Lisboa
Tipo: Dissertação de Mestrado
Publicado em /11/2011 Português
Relevância na Pesquisa
36.7%
A organização automática de mensagens de correio electrónico é um desafio actual na área da aprendizagem automática. O número excessivo de mensagens afecta cada vez mais utilizadores, especialmente os que usam o correio electrónico como ferramenta de comunicação e trabalho. Esta tese aborda o problema da organização automática de mensagens de correio electrónico propondo uma solução que tem como objectivo a etiquetagem automática de mensagens. A etiquetagem automática é feita com recurso às pastas de correio electrónico anteriormente criadas pelos utilizadores, tratando-as como etiquetas, e à sugestão de múltiplas etiquetas para cada mensagem (top-N). São estudadas várias técnicas de aprendizagem e os vários campos que compõe uma mensagem de correio electrónico são analisados de forma a determinar a sua adequação como elementos de classificação. O foco deste trabalho recai sobre os campos textuais (o assunto e o corpo das mensagens), estudando-se diferentes formas de representação, selecção de características e algoritmos de classificação. É ainda efectuada a avaliação dos campos de participantes através de algoritmos de classificação que os representam usando o modelo vectorial ou como um grafo. Os vários campos são combinados para classificação utilizando a técnica de combinação de classificadores Votação por Maioria. Os testes são efectuados com um subconjunto de mensagens de correio electrónico da Enron e um conjunto de dados privados disponibilizados pelo Institute for Systems and Technologies of Information...

Visualization study and quantitative velocity measurements in turbulent taylor-couette flow by phantomm flow tagging: a description of the transition to turbulence

Biage,M.; Campos,J. C. C.
Fonte: Associação Brasileira de Engenharia e Ciências Mecânicas - ABCM Publicador: Associação Brasileira de Engenharia e Ciências Mecânicas - ABCM
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2003 Português
Relevância na Pesquisa
36.7%
A visualization study and Quantitative velocity measurements have been performed in Taylor-Couette flow with a medium-gap (ç= 0.356), over a large range of Taylor numbers (2.1x10(4) < Ta < 1.1x10(11)), with the outer cylinder fixed and the inner cylinder rotating about its axis. Quantitative velocity measurements were carried out using the PHANTOMM flow tagging technique. Two techniques were used for visualization study: the PHANTOMM technique that allowed flow structure visualization from small to moderate Taylor numbers, and the Particle Streak Imaging, PSI (the flow was seeded with neutrally buoyant polystyrene micro spheres) that permitted the flow structure visualization from moderate to high Taylor numbers. The results illustrate the expected three-dimensional features of flow and presence of Taylor cells at low Taylor numbers. Our study examined the interplay between small and large scales present in the flow as well as showed the gradual transition to turbulence with increasing Taylor numbers. Taylor cells were found for Taylor numbers less than 1.13 x 10(10). At low Taylor numbers, the flow in the cells appeared to be a rotational laminar flow with a high degree of coherence. At higher Taylor numbers, the cells aspect became more irregular...

Coded wire tagging of juvenile curimbatá, Prochilodus lineatus (Valenciennes, 1837) (Characiformes): mortality, tag retention, and growth

Barroca,Tatiana M.; Gutiérrez-Espinosa,Mónica A.; Giraldo,Alejandro; Bedore,Alessandra G.; Godinho,Alexandre L.
Fonte: Sociedade Brasileira de Ictiologia Publicador: Sociedade Brasileira de Ictiologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2015 Português
Relevância na Pesquisa
37.04%
In recent decades, Brazilian hydroelectric reservoirs have been stocked with hundreds of millions of juvenile migratory fish, but almost no research on stocking has been conducted. In order to study stocking it is essential to tag the fish to be stocked. In this investigation we determined handling-induced mortality, tag retention rate, and absolute growth rate of hatchery-reared juvenile curimbatá (Prochilodus lineatus) tagged with coded wire tags (CWT), a tag widely used on stocked fish. We injected CWT into the dorsal musculature just below the first dorsal fin ray. Despite the need for frequent tag injector maintenance, this tagging location proved to be suitable for tagging juvenile curimbatá. We found no short-term mortality of juvenile curimbatá handled for CWT tagging, high retention rate for CWT (≥ 98.2%) even after 174 d of tagging, and no influence on absolute growth rate by CWT. We conclude that CWT is effective at tagging juvenile curimbatá, and we expect that it will also be effective for many other Brazilian fish species used for stocking.

The C-terminal amino acid sequence of nascent peptide is a major determinant of SsrA tagging at all three stop codons.

Sunohara, Takafumi; Abo, Tatsuhiko; Inada, Toshifumi; Aiba, Hiroji
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /11/2002 Português
Relevância na Pesquisa
27.13%
Recent studies on endogenous SsrA-tagged proteins have revealed that the tagging could occur at a position corresponding to the normal termination codon. During the study of SsrA-mediated Lacl tagging (Abo et al., EMBO J, 2000 19:3762-3769), we found that a variant Lacl (Lacl deltaC1) lacking the last C-terminal amino acid residue is efficiently tagged in a stop codon-dependent manner. SsrA tagging of Lacl deltaC1 occurred efficiently without Lacl binding to the lac operators at any one of three stop codons. The C-terminal (R)LESG peptide of Lacl deltaC1 was shown to trigger the SsrA tagging of an unrelated protein (CRP) when fused to its C terminus. Mass spectrometry analysis of the purified fusion proteins revealed that SsrA tagging occurs at a position corresponding to the termination codon. The alteration of the amino acid sequence but not the nucleotide sequence of the C-terminal portion eliminated the tagging. We also showed that the tagging-provoking sequences cause an efficient translational readthrough at UGA but not UAA codons. In addition, we found that C-terminal dipeptides known to induce an efficient translation readthrough could cause an efficient tagging at stop codons. We conclude that the amino acid sequence of nascent polypeptide prior to stop codons is a major determinant for the SsrA tagging at all three stop codons.

mRNA 3′ Tagging Is Induced by Nonsense-Mediated Decay and Promotes Ribosome Dissociation

Morozov, Igor Y.; Jones, Meriel G.; Gould, Peter D.; Crome, Victoria; Wilson, James B.; Hall, Anthony J. W.; Rigden, Daniel J.; Caddick, Mark X.
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /07/2012 Português
Relevância na Pesquisa
27.13%
For a range of eukaryote transcripts, the initiation of degradation is coincident with the addition of a short pyrimidine tag at the 3′ end. Previously, cytoplasmic mRNA tagging has been observed for human and fungal transcripts. We now report that Arabidopsis thaliana mRNA is subject to 3′ tagging with U and C nucleotides, as in Aspergillus nidulans. Mutations that disrupt tagging, including A. nidulans cutA and a newly characterized gene, cutB, retard transcript degradation. Importantly, nonsense-mediated decay (NMD), a major checkpoint for transcript fidelity, elicits 3′ tagging of transcripts containing a premature termination codon (PTC). Although PTC-induced transcript degradation does not require 3′ tagging, subsequent dissociation of mRNA from ribosomes is retarded in tagging mutants. Additionally, tagging of wild-type and NMD-inducing transcripts is greatly reduced in strains lacking Upf1, a conserved NMD factor also required for human histone mRNA tagging. We argue that PTC-induced translational termination differs fundamentally from normal termination in polyadenylated transcripts, as it leads to transcript degradation and prevents rather than facilitates further translation. Furthermore, transcript deadenylation and the consequent dissociation of poly(A) binding protein will result in PTC-like termination events which recruit Upf1...

Upper Tag Ontology (UTO) For Integrating Social Tagging Data

Foo, Schubert; Toma, Ioan; Fried, Michael; Yan, Erjia; Ding, Ying; Jacob, Elin K.
Fonte: Journal of the American Society for Information Science and Technology Publicador: Journal of the American Society for Information Science and Technology
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
37.04%
Data integration and mediation have become central concerns of information technology over the past few decades. With the advent of the Web and the rapid increases in the amount of data and the number of Web documents and users, researchers have focused on enhancing the interoperability of data through the development of metadata schemes. Other researchers have looked to the wealth of metadata generated by bookmarking sites on the Social Web. While several existing ontologies have capitalized on the semantics of metadata created by tagging activities, the Upper Tag Ontology (UTO) emphasizes the structure of tagging activities to facilitate modeling of tagging data and the integration of data from different bookmarking sites as well as the alignment of tagging ontologies. UTO is described and its utility in modeling, harvesting, integrating, searching, and analyzing data is demonstrated with metadata harvested from three major social tagging systems (Delicious, Flickr, and YouTube).

A HUBzero Extension for Automated Tagging

Mullen, Jim
Fonte: Universidade de Indiana Publicador: Universidade de Indiana
Tipo: Conferência ou Objeto de Conferência
Português
Relevância na Pesquisa
36.92%
This presentation was given at the HUBbub 2013 Conference in Indianapolis, Indiana, U.S.A. on September 6, 2013.; Tagging pages on a hub can help users find relevant content, but it also can require a lot of effort if done manually. We developed an extension for HUBzero that supports the automated tagging of content using the NCBO (National Center for Biomedical Ontology) Annotator; and we have installed this extension on the Indiana CTSI (Clinical and Translational Sciences Institute) Hub. This presentation covers the capabilities of this extension.; Supported by NIH/NCRR ARRA Supplement to the Indiana CTSI, # 3UL1RR025761-02S3

Conceptualization and visualization of tagging and folksonomies

Lohmann, Steffen
Fonte: Universidade Carlos III de Madrid Publicador: Universidade Carlos III de Madrid
Tipo: Tese de Doutorado
Português
Relevância na Pesquisa
37.1%
Tagging has become a popular indexing method for interactive systems in the past decade. It offers a simple yet effective way for users to organize an ever increasing amount of digital information for themselves and/or others. The linked user vocabulary resulting from tagging is known as folksonomy and provides a valuable source for the retrieval and exploration of digital resources. Although several models and representations of tagging have been proposed, there is no coherent conceptualization that provides a comprehensive and precise description of the concepts and relationships in the domain. Furthermore, there is little systematic research in the area of folksonomy visualization, and so folksonomies are still mainly depicted as simple tag clouds. Both problems are related, as a well-defined conceptualization is an important prerequisite for the interoperable use and visualization of folksonomies. In this thesis, we address these shortcomings by developing a coherent conceptualization of tagging and visualizations for the interactive exploration of folksonomies. We provide an overview and comparison of tagging models and define the key concepts of the domain. After a comprehensive review of existing tagging ontologies, we present a unified and coherent conceptualization that incorporates the best parts of the reviewed ontologies. The conceptualization is implemented in the Web Ontology Language and allows for scalable reasoning on folksonomies. Building on the conceptualization...

Activation tagging in Solanum tuberosum: Innate immune activation affects potato tuber periderm development

Frank, Daniel
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
Português
Relevância na Pesquisa
36.7%
Activation-tagging is a functional genomics technique where strong enhancers are inserted randomly into target genomes to over-activate endogenous genes. Phenotypes of interest can be selected for investigation of genetic factors contributing to the mutant phenotype. From initial screens of a population of activation-tagged potato, a mutant with chocolate-coloured tuber skin has been identified. In this thesis, a novel sequence capture method for identifying T-DNA loci in activation tagged potato was used to characterize chocolate’s single T-DNA insertion locus. Transcriptome analysis of tuber periderm tissue was used to identify major processes occurring in the chocolate mutant. Our data suggest activation of a chitin-binding receptor-like kinase located 65 kb from T-DNA insert may cause activation of immune signaling pathways in chocolate. The present work explores a putative model of transcriptional and cellular responses involved in gain-of-function immune receptor activation. Selectively, these findings illustrate the periderm tissue as an important area of defense charged against biotic and abiotic stresses. Periderm development and anatomy are highly important for tuber storage. Further characterization of potato tuber periderm may contribute knowledge to model periderm systems and have implications for molecular breeding strategies to improve tuber storage quality.; Thesis (Master...

Social Structure in Tagging Practices: Reality or Myth?

Fani Marvasti, AMIN
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado Formato: 4356498 bytes; application/pdf
Português
Relevância na Pesquisa
37.13%
Tagging is widely adopted in so-called "collaborative-tagging" systems which are one of the Web 2.0 applications that have achieved lots of attention lately. They provide services for users to store, manage and search web resources with the help of freely chosen keywords, called "tags". Because of the high-volume usage of these systems and the annotations that users provide by their tags, these systems are regarded as good targets for disciplines like knowledge discovery. Roughly, two lines of research have been pursued so far on collaborative tagging: to study the structure of tags and to study their functionality in web search. In this research we investigated tagging structures in a popular collaborative-tagging system, called del.icio.us, by focusing on the relations of "tags", "users" and "web resources", three main components of any collaborative-tagging system. Particularly we are interested in finding whether there are social structures that could be used to increase the usability of these systems for content retrieval and navigation. Our results show that people mainly use tags for their own informational needs which are personal rather than social. Any social structure or communities around tags and users is rare and weak which suggests that collaborative tagging has not added much to personal bookmarking. However...

The Tagging Mediation on Semantic Web; A mediação do tagging na web semântic

Gonçalves, Leandro Tavares
Fonte: Universidade de São Paulo. Escola de Comunicações e Artes Publicador: Universidade de São Paulo. Escola de Comunicações e Artes
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; Formato: application/pdf
Publicado em 30/12/2006 Português
Relevância na Pesquisa
36.99%
This article aims to contextualize Tagging technology in the virtual environment and reflect on the construction of collective meanings of the semantic web in the space-time interaction.; Esse artigo tem como principal objetivo contextualizar a tecnologia Tagging no ambiente virtual e refletir sobre a conexão da sociedade na construção dos significados coletivos da chamada web semântica na interação espaço-tempo. 

Evaluation of Deformable Image Registration for Lung Motion Estimation using Hyperpolarized Gas Tagging MRI

Huang, Qijie
Fonte: Universidade Duke Publicador: Universidade Duke
Tipo: Tese de Doutorado
Publicado em //2014 Português
Relevância na Pesquisa
37.07%

Purpose: Hyperpolarized gas (HP) tagging MRI is a novel imaging technique for direct measurement of lung motion during breathing. This study aims to quantitatively evaluate the accuracy of deformable image registration (DIR) in lung motion estimation using HP tagging MRI as references.

Method: Three healthy subjects were imaged using the HP MR tagging, as well as a high-resolution 3D proton MR sequence (TrueFISP) at the end-of-inhalation (EOI) and the end-of-exhalation (EOE). Ground truth of lung motion and corresponding displacement vector field (tDVF) was derived from HP tagging MRI by manually tracking the displacement of tagging grids between EOI and EOE. Seven different DIR methods were applied to the high-resolution TrueFISP MR images (EOI and EOE) to generate the DIR-based DVFs (dDVF). The DIR methods include Velocity (VEL), MIM, Mirada, multi-grid B-spline from Elastix (MGB) and 3 other algorithms from DIRART toolbox (Double Force Demons (DFD), Improved Lucas-Kanade (ILK), and Iterative Optical Flow (IOF)). All registrations were performed by independent experts. Target registration error (TRE) was calculated as tDVF - dDVF. Analysis was performed for the entire lungs, and separately for the upper and lower lungs.

Results: Significant differences between tDVF and dDVF were observed. Besides the DFD and IOF algorithms...

Mild tagging procedures for the structural analysis of glycans

Ramsay, Steven; Freeman, Craig; Grace, Philip; Redmond, J; MacLeod, John
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
36.7%
The reductive oxyamination of model glycan structures has been investigated as a mild, alternative tagging procedure to reductive amination using O-(4-nitrobenzyl)-hydroxylamine. Oxime formation was quantitative, but the reduction step did not always go to completion. Novel O- and N-substituted 7-hydroxycoumaryl- and 3-methoxybenzylhydroxylamines were synthesized and shown to couple quantitatively with model saccharides by oxime formation and reductive hydroxyamination, respectively, under very mild, aqueous conditions. The fluorescent derivatives produced show good chromatographic and mass spectrometric properties. Both procedures are suitable for the labeling of carbohydrates and oligosaccharide fragments from glycosaminoglycan structures, such as heparin and heparan sulfate.

Mark-recapture by genetic tagging reveals restricted movements by bush rats ( Rattus fuscipes ) in a fragmented landscape

Peakall, Rodney; Ebert, Daniel; Cunningham, Ross; Lindenmayer, David
Fonte: Zoological Society of London Publicador: Zoological Society of London
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
36.7%
We applied genetic tagging (the identification of individuals by genetic markers) as part of a demographic and genetic analysis of a manipulative study of bush rats Rattus fuscipes in a fragmented landscape in south-eastern Australia. Our study comprised

Web-based Bengali News Corpus for Lexicon Development and POS Tagging

Ekbal,Asif; Bandyopadhyay,Sivaji
Fonte: Instituto Politécnico Nacional, Centro de Innovación y Desarrollo Tecnológico en Cómputo Publicador: Instituto Politécnico Nacional, Centro de Innovación y Desarrollo Tecnológico en Cómputo
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2008 Português
Relevância na Pesquisa
36.83%
Lexicon development and Part of Speech (POS) tagging are very important for almost all Natural Language Processing (NLP) applications. The rapid development of these resources and tools using machine learning techniques for less computerized languages requires appropriately tagged corpus. We have used a Bengali news corpus, developed from the web archive of a widely read Bengali newspaper. The corpus contains approximately 34 million wordforms. This corpus is used for lexicon development without employing extensive knowledge of the language. We have developed the POS taggers using Hidden Markov Model (HMM) and Support Vector Machine (SVM). The lexicon contains around 128 thousand entries and a manual check yields the accuracy of 79.6%. Initially, the POS taggers have been developed for Bengali and shown the accuracies of 85.56%, and 91.23% for HMM, and SVM, respectively. Based on the Bengali news corpus, we identify various word-level orthographic features to use in the POS taggers. The lexicon and a Named Entity Recognition (NER) system, developed using this corpus, are also used in POS tagging. The POS taggers are then evaluated with Hindi and Telugu data. Evaluation results demonstrates the fact that SVM performs better than HMM for all the three Indian languages.