Search results for "Unsupervised"

Hits ?▲	Authors	Title	Venue	Year	Link	Author keywords
17	Manabu Kawada, Xu Wu, Tadashi Ae	A construction of neural-net based AI systems.	ICECCS	1995	DBLP DOI BibTeX RDF	neural-net based AI system construction, neural network technique, real-time neuron-based AI architecture, NAI, real-time case-based reasoning system, winner-take-all type neural network, real-time classification, real-time retrieval, massive case-base, flexible learning, self-organizing learning algorithm, LVQ1 learning algorithm, real-time systems, learning (artificial intelligence), knowledge based systems, unsupervised learning, supervised learning, case-based reasoning, pattern classification, learning algorithms, algorithm theory, neural net architecture
17	Dit-Yan Yeung	A grammatical inference approach to on-line handwriting modeling and recognition: a pilot study.	ICDAR	1995	DBLP DOI BibTeX RDF	on-line handwriting modeling, discrete-time recurrent neural network, subgrammar network models, temporal sequence processing, handwriting recognition, unsupervised learning, inference mechanisms, grammatical inference, temporal sequences
17	Jack-Gérard Postaire, R. D. Zhang, C. Lecocq-Botte	Cluster Analysis by Binary Morphology.	IEEE Trans. Pattern Anal. Mach. Intell.	1993	DBLP DOI BibTeX RDF	binary morphology, unsupervised pattern classification, mathematical morphology operations, multidimensional observations, mathematical discrete binary set, well separated subsets, pattern recognition, set theory
17	Kenneth Rose, Eitan Gurewitz, Geoffrey C. Fox	Constrained Clustering as an Optimization Method.	IEEE Trans. Pattern Anal. Mach. Intell.	1993	DBLP DOI BibTeX RDF	cluster mass variables, total mass constraint, second Lagrange multiplier, open path constraint, optimization, pattern recognition, pattern recognition, simulated annealing, information theory, dimensionality reduction, unsupervised learning, traveling salesman problem, neural nets, neural nets, maximum entropy, phase transitions, deterministic annealing, constraint theory, constrained clustering, elastic net
17	S. C. Chan, Andrew K. C. Wong	Synthesis and Recognition of Sequences.	IEEE Trans. Pattern Anal. Mach. Intell.	1991	DBLP DOI BibTeX RDF	sequences synthesis, sequences recognition, hierarchical sequence synthesis procedure, taxonomic hierarchy, unsupervised classification procedure, pattern recognition, probability, alignment, supervised classification, alphabet
17	Michael Unser, Murray Eden	Multiresolution Feature Extraction and Selection for Texture Segmentation.	IEEE Trans. Pattern Anal. Mach. Intell.	1989	DBLP DOI BibTeX RDF	multiresolution feature extraction, multiresolution feature selection, local linear transforms, maximal texture discrimination, texture energy measures, iterative Gaussian smoothing, half-octave scale progression, scatter matrices, pattern recognition, texture segmentation, unsupervised segmentation, feature reduction
16	Xirong Li 0001, Cees G. M. Snoek, Marcel Worring	Unsupervised multi-feature tag relevance learning for social image retrieval.	CIVR	2010	DBLP DOI BibTeX RDF	multi-feature, social image retrieval, tag relevance learning
16	Xiaogang Wang 0001, Xiaoxu Ma, W. Eric L. Grimson	Unsupervised Activity Perception in Crowded and Complicated Scenes Using Hierarchical Bayesian Models.	IEEE Trans. Pattern Anal. Mach. Intell.	2009	DBLP DOI BibTeX RDF
16	Kai Yu 0004, Mark J. F. Gales, Philip C. Woodland	Unsupervised Adaptation With Discriminative Mapping Transforms.	IEEE Trans. Speech Audio Process.	2009	DBLP DOI BibTeX RDF
16	Sankaranarayanan Ananthakrishnan, Shrikanth S. Narayanan	Unsupervised Adaptation of Categorical Prosody Models for Prosody Labeling and Speech Recognition.	IEEE Trans. Speech Audio Process.	2009	DBLP DOI BibTeX RDF
16	Eduardo Sánchez-Soto, Alexandros Potamianos, Khalid Daoudi	Unsupervised Stream-Weights Computation in Classification and Recognition Tasks.	IEEE Trans. Speech Audio Process.	2009	DBLP DOI BibTeX RDF
16	Lydia Tapia, Shawna L. Thomas, Bryan Boyd, Nancy M. Amato	An unsupervised adaptive strategy for constructing probabilistic roadmaps.	ICRA	2009	DBLP DOI BibTeX RDF
16	Maheyzah Md Siraj, Mohd Aizaini Maarof, Siti Zaiton Mohd Hashim	Intelligent Clustering with PCA and Unsupervised Learning Algorithm in Intrusion Alert Correlation.	IAS	2009	DBLP DOI BibTeX RDF
16	Michal Haindl, Stanislav Mikes, Pavel Pudil	Unsupervised Hierarchical Weighted Multi-segmenter.	MCS	2009	DBLP DOI BibTeX RDF
16	Hui Xue 0006, Sven Zühlsdorff, Peter Kellman, Andrew E. Arai, Sonia Nielles-Vallespin, Christophe Chefd'Hotel, Christine H. Lorenz, Jens Guehring	Unsupervised Inline Analysis of Cardiac Perfusion MRI.	MICCAI (1)	2009	DBLP DOI BibTeX RDF
16	Gyula Papp	Vector-Based Unsupervised Word Sense Disambiguation for Large Number of Contexts.	TSD	2009	DBLP DOI BibTeX RDF
16	Ralph Ewerth, Bernd Freisleben	Performance Prediction for Unsupervised Video Indexing.	CAIP	2009	DBLP DOI BibTeX RDF	video retrieval, Performance prediction, video indexing
16	Wei Pan, Lorenzo Torresani	Unsupervised hierarchical modeling of locomotion styles.	ICML	2009	DBLP DOI BibTeX RDF
16	Linli Xu, Martha White, Dale Schuurmans	Optimal reverse prediction: a unified perspective on supervised, unsupervised and semi-supervised learning.	ICML	2009	DBLP DOI BibTeX RDF
16	Anke Meyer-Bäse, Vera Thümmler	Local and Global Stability Analysis of an Unsupervised Competitive Neural Network.	IEEE Trans. Neural Networks	2008	DBLP DOI BibTeX RDF
16	A. S. Park, James R. Glass	Unsupervised Pattern Discovery in Speech.	IEEE Trans. Speech Audio Process.	2008	DBLP DOI BibTeX RDF
16	Olga Kubassova, Mikael Boesen, Henning Bliddal	General framework for unsupervised evaluation of quality of segmentation results.	ICIP	2008	DBLP DOI BibTeX RDF
16	David M. Chen, David P. Varodayan, Markus Flierl, Bernd Girod	Wyner-ZIV coding of multiview images with unsupervised learning of disparity and Gray code.	ICIP	2008	DBLP DOI BibTeX RDF
16	Ferda Ofli, Engin Erzin, Yücel Yemez, A. Murat Tekalp, Çigdem Eroglu Erdem, A. Tanju Erdem, Tolga Abaci, Mehmet K. Özkan	Unsupervised dance figure analysis from video for dancing Avatar animation.	ICIP	2008	DBLP DOI BibTeX RDF
16	Débora C. Corrêa, Alexandre L. M. Levada, José Hiroki Saito, João F. Mari	Neural network based systems for computer-aided musical composition: supervised x unsupervised learning.	SAC	2008	DBLP DOI BibTeX RDF	learning, artificial neural network, self-organized maps, back-propagation, musical composition
16	Bin Tan, Fuchun Peng	Unsupervised query segmentation using generative language models and wikipedia.	WWW	2008	DBLP DOI BibTeX RDF	query segmentation, concept discovery
16	Jing Yuan, Zhu Li, Ruixi Yuan	Information Entropy Based Clustering Method for Unsupervised Internet Traffic Classification.	ICC	2008	DBLP DOI BibTeX RDF
16	Kewei Tu, Vasant G. Honavar	Unsupervised Learning of Probabilistic Context-Free Grammar using Iterative Biclustering.	ICGI	2008	DBLP DOI BibTeX RDF
16	Yu Qiao 0001, Naoya Shimomura, Nobuaki Minematsu	Unsupervised optimal phoneme segmentation: Objectives, algorithm and comparisons.	ICASSP	2008	DBLP DOI BibTeX RDF
16	Lin Zhong 0001, Chao Li 0001, Huan Li, Zhang Xiong 0001	Unsupervised Clustering Algorithm for Video Shots Using Spectral Division.	ISVC (1)	2008	DBLP DOI BibTeX RDF
16	René Arnulfo García-Hernández, Romyna Montiel Soto, Yulia Ledeneva, Eréndira Rendón, Alexander F. Gelbukh, José Rafael Cruz Reyes	Text Summarization by Sentence Extraction Using Unsupervised Learning.	MICAI	2008	DBLP DOI BibTeX RDF
16	Michal Haindl, Stanislav Mikes	Unsupervised mammograms segmentation.	ICPR	2008	DBLP DOI BibTeX RDF
16	Robert J. Hall 0002, Charles Sutton, Andrew McCallum	Unsupervised deduplication using cross-field dependencies.	KDD	2008	DBLP DOI BibTeX RDF	dirichlet process mixture, data mining, information extraction, deduplication
16	Santa Di Cataldo, Elisa Ficarra, Enrico Macii	Automated Discrimination of Pathological Regions in Tissue Images: Unsupervised Clustering vs. Supervised SVM Classification.	BIOSTEC (Selected Papers)	2008	DBLP DOI BibTeX RDF	Tissue segmentation, tissue confocal images, immunohistochemistry, Support Vector Machine, K-means clustering
16	Reuben Smith, Nathalie Japkowicz, Maxwell G. Dondo, Peter Mason	Using Unsupervised Learning for Network Alert Correlation.	Canadian AI	2008	DBLP DOI BibTeX RDF
16	Chi Zhang, Hongbin Zhang	An unsupervised approach to determination of main subject regions in images with low depth of field.	MMSP	2008	DBLP DOI BibTeX RDF
16	Gunhee Kim, Christos Faloutsos, Martial Hebert	Unsupervised modeling and recognition of object categories with combination of visual contents and geometric similarity links.	Multimedia Information Retrieval	2008	DBLP DOI BibTeX RDF	object recognition, image retrieval
16	Fei Jiang, Hugues Berry, Marc Schoenauer	Unsupervised learning of echo state networks: balancing the double pole.	GECCO	2008	DBLP DOI BibTeX RDF	evolution strategies, CMA-ES, echo state networks
16	Roman Sandler, Michael Lindenbaum	Unsupervised estimation of segmentation quality using nonnegative factorization.	CVPR	2008	DBLP DOI BibTeX RDF
16	Josef Sivic, Bryan C. Russell, Andrew Zisserman, William T. Freeman, Alexei A. Efros	Unsupervised discovery of visual object class hierarchies.	CVPR	2008	DBLP DOI BibTeX RDF
16	Gunhee Kim, Christos Faloutsos, Martial Hebert	Unsupervised modeling of object categories using link analysis techniques.	CVPR	2008	DBLP DOI BibTeX RDF
16	Ajmal S. Mian	Unsupervised learning from local features for video-based face recognition.	FG	2008	DBLP DOI BibTeX RDF
16	Rui Nian, Guangrong Ji, Michel Verleysen	An Unsupervised Gaussian Mixture Classification Mechanism Based on Statistical Learning Analysis.	FSKD (2)	2008	DBLP DOI BibTeX RDF
16	Gerd Brunner, Uday Kurkure, Deepak Roy Chittajallu, Raja P. Yalamanchili, Ioannis A. Kakadiaris	Toward Unsupervised Classification of Calcified Arterial Lesions.	MICCAI (1)	2008	DBLP DOI BibTeX RDF
16	Cartic Ramakrishnan, Pablo N. Mendes, Shaojun Wang, Amit P. Sheth	Unsupervised Discovery of Compound Entities for Relationship Extraction.	EKAW	2008	DBLP DOI BibTeX RDF	compound entity identification, relational knowledge acquisition, Information extraction, relationship extraction
16	Tak-Lam Wong, Wai Lam, Tik-Shun Wong	An unsupervised framework for extracting and normalizing product attributes from multiple web sites.	SIGIR	2008	DBLP DOI BibTeX RDF	attribute normalization, web mining, attribute extraction
16	Wei Wang 0269, Huihui Zhao, Jianxin Chen, Jing Chen, Guangcheng Xi	Bridge the gap between syndrome in Traditional Chinese Medicine and proteome in western medicine by unsupervised pattern discovery algorithm.	ICNSC	2008	DBLP DOI BibTeX RDF
16	Long Zhu, Chenxi Lin, Haoda Huang, Yuanhao Chen, Alan L. Yuille	Unsupervised Structure Learning: Hierarchical Recursive Composition, Suspicious Coincidence and Competitive Exclusion.	ECCV (2)	2008	DBLP DOI BibTeX RDF
16	Sebastian Nowozin, Gökhan H. Bakir	A decoupled approach to exemplar-based unsupervised learning.	ICML	2008	DBLP DOI BibTeX RDF
16	Mikalai Krapivin, Maurizio Marchese, Andrei Yadrantsau, Yanchun Liang 0001	Unsupervised key-phrases extraction from scientific papers using domain and linguistic knowledge.	ICDIM	2008	DBLP DOI BibTeX RDF
16	Dalila Benboudjema, Wojciech Pieczynski	Unsupervised Statistical Segmentation of Nonstationary Images Using Triplet Markov Fields.	IEEE Trans. Pattern Anal. Mach. Intell.	2007	DBLP DOI BibTeX RDF	Triplet Markov fields, statistical image segmentation, paramater estimation, Pearson system, iterative conditional estimation, nonstationary images, textures classification
16	Rongqing Huang, John H. L. Hansen	Unsupervised Discriminative Training With Application to Dialect Classification.	IEEE Trans. Speech Audio Process.	2007	DBLP DOI BibTeX RDF
16	Matthew W. B. Trotter, Bernard F. Buxton	Unsupervised Thresholding of Affymetrix Microarray Data.	ICCTA	2007	DBLP DOI BibTeX RDF
16	Alexander Ivanyukovich, Maurizio Marchese, Patrick Reuther	Assessing Quality Dynamics in Unsupervised Metadata Extraction for Digital Libraries.	ECDL	2007	DBLP DOI BibTeX RDF
16	Kazuyuki Narisawa, Hideo Bannai, Kohei Hatano, Masayuki Takeda	Unsupervised Spam Detection Based on String Alienness Measures.	Discovery Science	2007	DBLP DOI BibTeX RDF
16	Yuan Kui Shen, David R. Karger	U-REST: an unsupervised record extraction system.	WWW	2007	DBLP DOI BibTeX RDF	record extraction, clustering
16	Álvaro Herrero 0001, Emilio Corchado, Paolo Gastaldo, Davide Leoncini, Francesco Picasso, Rodolfo Zunino	Intrusion Detection at Packet Level by Unsupervised Architectures.	IDEAL	2007	DBLP DOI BibTeX RDF	Auto Associative Back Propagation, Network Security, Self-Organizing Map, Intrusion Detection System, Vector Quantization
16	Zhiwu Lu 0001, Xiaoqing Lu, Zhiyuan Ye	Unsupervised Image Categorization Using Constrained Entropy-Regularized Likelihood Learning with Pairwise Constraints.	ISNN (1)	2007	DBLP DOI BibTeX RDF
16	Jinglu Hu, Takafumi Sasakawa, Kotaro Hirasawa, Huiru Zheng	A Hierarchical Learning System Incorporating with Supervised, Unsupervised and Reinforcement Learning.	ISNN (1)	2007	DBLP DOI BibTeX RDF
16	David P. Varodayan, Aditya Mavlankar, Markus Flierl, Bernd Girod	Distributed Grayscale Stereo Image Coding with Unsupervised Learning of Disparity.	DCC	2007	DBLP DOI BibTeX RDF
16	Delphine Bernhard	Simple Morpheme Labelling in Unsupervised Morpheme Analysis.	CLEF	2007	DBLP DOI BibTeX RDF
16	Bo Wu 0001, Ram Nevatia	Improving Part based Object Detection by Unsupervised, Online Boosting.	CVPR	2007	DBLP DOI BibTeX RDF
16	Tanveer Fathima Syeda-Mahmood, Fei Wang 0002	Unsupervised Clustering using Multi-Resolution Perceptual Grouping.	CVPR	2007	DBLP DOI BibTeX RDF
16	Michael Donoser, Horst Bischof	ROI-SEG: Unsupervised Color Segmentation by Combining Differently Focused Sub Results.	CVPR	2007	DBLP DOI BibTeX RDF
16	Marc'Aurelio Ranzato, Fu Jie Huang, Y-Lan Boureau, Yann LeCun	Unsupervised Learning of Invariant Feature Hierarchies with Applications to Object Recognition.	CVPR	2007	DBLP DOI BibTeX RDF
16	Ravi Som Sinha, Rada Mihalcea	Unsupervised Graph-basedWord Sense Disambiguation Using Measures of Word Semantic Similarity.	ICSC	2007	DBLP DOI BibTeX RDF
16	Devi Parikh, Tsuhan Chen	Unsupervised Identification of Multiple Objects of Interest from Multiple Images: dISCOVER.	ACCV (2)	2007	DBLP DOI BibTeX RDF
16	Luciano Spinello, Roland Siegwart	Unsupervised Detection of Artificial Objects in Outdoor Environments.	FSR	2007	DBLP DOI BibTeX RDF
16	Nizar Bouguila, Djemel Ziou	Unsupervised Selection of a Finite Dirichlet Mixture Model: An MML-Based Approach.	IEEE Trans. Knowl. Data Eng.	2006	DBLP DOI BibTeX RDF	Dirichlet mixture, shadow modeling, texture summarization, EM, SAR images, Finite mixture models, MML
16	Michael W. Graham, David J. Miller 0001	Unsupervised learning of parsimonious mixtures on large spaces with integrated feature and component selection.	IEEE Trans. Signal Process.	2006	DBLP DOI BibTeX RDF
16	Patrick Lehti, Peter Fankhauser	Unsupervised Duplicate Detection Using Sample Non-duplicates.	J. Data Semantics	2006	DBLP DOI BibTeX RDF
16	Jacob Goldberger, Shiri Gordon, Hayit Greenspan	Unsupervised image-set clustering using an information theoretic framework.	IEEE Trans. Image Process.	2006	DBLP DOI BibTeX RDF
16	Rongqing Huang, John H. L. Hansen	Advances in unsupervised audio classification and segmentation for the broadcast news and NGSW corpora.	IEEE Trans. Speech Audio Process.	2006	DBLP DOI BibTeX RDF
16	Binyamin Rosenfeld, Ronen Feldman	High-Performance Unsupervised Relation Extraction from Large Corpora.	ICDM	2006	DBLP DOI BibTeX RDF
16	Diego Sona, Sriharsha Veeramachaneni, Nicola Polettini, Paolo Avesani	Regularization for Unsupervised Classification on Taxonomies.	ISMIS	2006	DBLP DOI BibTeX RDF
16	Haifeng Chen, Guofei Jiang, Cristian Ungureanu, Kenji Yoshihira	Combining supervised and unsupervised monitoring for fault detection in distributed computing systems.	SAC	2006	DBLP DOI BibTeX RDF	supervised monitoring, distributed computing, fault detection, internet services, canonical correlation analysis
16	Goh Kawai	Collaborative peer-based language learning in unsupervised asynchronous online environments.	C5	2006	DBLP DOI BibTeX RDF
16	Oliver Brdiczka, Dominique Vaufreydaz, Jérôme Maisonnasse, Patrick Reignier	Unsupervised Segmentation of Meeting Configurations and Activities using Speech Activity Detection.	AIAI	2006	DBLP DOI BibTeX RDF
16	Gustavo B. Borba, Humberto R. Gamba, Oge Marques, Liam M. Mayron	An unsupervised method for clustering images based on their salient regions of interest.	ACM Multimedia	2006	DBLP DOI BibTeX RDF	clustering, image retrieval, visual attention
16	Xiangrong Zhang, Bin Lu 0002, Shuiping Gou, Licheng Jiao	Immune Multiobjective Optimization Algorithm for Unsupervised Feature Selection.	EvoWorkshops	2006	DBLP DOI BibTeX RDF
16	Mario Fritz, Bernt Schiele	Towards Unsupervised Discovery of Visual Categories.	DAGM-Symposium	2006	DBLP DOI BibTeX RDF
16	Massimo De Santo, Gennaro Percannella, Carlo Sansone, Mario Vento	Unsupervised News Video Segmentation by Combined Audio-Video Analysis.	MRCS	2006	DBLP DOI BibTeX RDF
16	Suyash P. Awate, Tolga Tasdizen, Ross T. Whitaker	Unsupervised Texture Segmentation with Nonparametric Neighborhood Statistics.	ECCV (2)	2006	DBLP DOI BibTeX RDF
16	Juan Pablo de la Cruz Gutiérrez	An Unsupervised Learning Rule for Class Discrimination in a Recurrent Neural Network.	ICANN (1)	2006	DBLP DOI BibTeX RDF
16	Henning Redestig, Florian Sohler, Ralf Zimmer, Joachim Selbig	Unsupervised Decision Trees Structured by Gene Ontology (GO-UDTs) for the Interpretation of Microarray Data.	GfKl	2006	DBLP DOI BibTeX RDF
16	Wei Chu, Xi Xiao, Jia Liu 0001	Confidence Score Based Unsupervised Incremental Adaptation for OOV Words Detection.	SSPR/SPR	2006	DBLP DOI BibTeX RDF
16	Lie Lu, HongJiang Zhang	Unsupervised speaker segmentation and tracking in real-time audio content analysis.	Multim. Syst.	2005	DBLP DOI BibTeX RDF	Audio content analysis, Speaker segmentation, Audio indexing, Speaker tracking, Speaker change detection
16	Sinisa Todorovic, Michael C. Nechyba	Dynamic Trees for Unsupervised Segmentation and Matching of Image Regions.	IEEE Trans. Pattern Anal. Mach. Intell.	2005	DBLP DOI BibTeX RDF	dynamic trees, image segmentation, object recognition, Bayesian networks, image matching, Generative models, variational inference
16	Lin Yang, Peter Meer, David J. Foran	Unsupervised segmentation based on robust estimation and color active contour models.	IEEE Trans. Inf. Technol. Biomed.	2005	DBLP DOI BibTeX RDF
16	Sanghoon Lee 0004, Melba M. Crawford	Unsupervised multistage image classification using hierarchical clustering with a bayesian similarity measure.	IEEE Trans. Image Process.	2005	DBLP DOI BibTeX RDF
16	Frank Wessel, Hermann Ney	Unsupervised training of acoustic models for large vocabulary continuous speech recognition.	IEEE Trans. Speech Audio Process.	2005	DBLP DOI BibTeX RDF
16	Eu-Gene Siew, Kate A. Smith, Leonid Churilov, Jeff Wassertheil	A Longitudinal Comparison of Supervised and Unsupervised Learning Approaches to Iso-Resource Grouping for Acute Healthcare in Australia.	Classification and Clustering for Knowledge Discovery	2005	DBLP DOI BibTeX RDF
16	John M. Winn, Nebojsa Jojic	LOCUS: Learning Object Classes with Unsupervised Segmentation.	ICCV	2005	DBLP DOI BibTeX RDF
16	Iraklis Varlamis, Ioannis Apostolakis, Marianthi Karatza	A Framework for Monitoring the Unsupervised Educational Process and Adapting the Content and Activities to Students' Needs.	WISE Workshops	2005	DBLP DOI BibTeX RDF
16	Mayank Tyagi, Ankit K. Mehra, Subhasis Chaudhuri, Lorenzo Bruzzone	Unsupervised Classification of Remote Sensing Data Using Graph Cut-Based Initialization.	PReMI	2005	DBLP DOI BibTeX RDF
16	Pavel Laskov, Patrick Düssel, Christin Schäfer, Konrad Rieck	Learning Intrusion Detection: Supervised or Unsupervised?.	ICIAP	2005	DBLP DOI BibTeX RDF
16	Maurizio Filippone, Francesco Masulli, Stefano Rovetta	Unsupervised Gene Selection and Clustering Using Simulated Annealing.	WILF	2005	DBLP DOI BibTeX RDF
16	Fang Liu 0001, Leping Lin	Unsupervised Anomaly Detection Based on an Evolutionary Artificial Immune Network.	EvoWorkshops	2005	DBLP DOI BibTeX RDF
16	Sunee Pongpinigpinyo, Wanchai Rivepiboon	Word Sense Disambiguation of Thai Language with Unsupervised Learning.	KES (1)	2005	DBLP DOI BibTeX RDF
16	Shen Furao, Osamu Hasegawa	An On-Line Learning Mechanism for Unsupervised Classification and Topology Representation.	CVPR (1)	2005	DBLP DOI BibTeX RDF