Search results for "User-Profile"

Hits ?▲	Authors	Title	Venue	Year	Link	Author keywords
72	Sung-Hyuk Park, Sang Pil Han, Soon-Young Huh, Hojin Lee	Preprocessing Uncertain User Profile Data: Inferring User's Actual Age from Ages of the User's Neighbors.	ICDE	2009	DBLP DOI BibTeX RDF
64	Trong Hai Duong, Mohammed Nazim Uddin, Delong Li, GeunSik Jo	A Collaborative Ontology-Based User Profiles System.	ICCCI	2009	DBLP DOI BibTeX RDF	Ontology-based user profile, Ontology, user profile, Ontology Integration
57	Mariam Daoud, Lynda Tamine-Lechani, Mohand Boughanem, Bilal Chebaro	A session based personalized search using an ontological user profile.	SAC	2009	DBLP DOI BibTeX RDF	session boundary, ontology, personalization, user profile
55	Zhiwen Yu 0001, Xingshe Zhou 0001, Yanbin Hao, Jianhua Gu	TV Program Recommendation for Multiple Viewers Based on user Profile Merging.	User Model. User Adapt. Interact.	2006	DBLP DOI BibTeX RDF	Television program recommendation, Multiple viewers, User profile merging, Total distance minimization, Digital television
49	Julio Cesar Royer, Roberto Willrich, Michel Diaz	User Profile-Based Authorization Policies for Network QoS Services.	NCA	2008	DBLP DOI BibTeX RDF	QoS, Policies, User Profile
49	Claudio Teixeira, Joaquim Sousa Pinto, Joaquim Arnaldo Martins	User Profiles in Corporate Scenarios.	ICIW	2008	DBLP DOI BibTeX RDF	Dynamic user profile, Profile management using web services, User profile, Stereotypes
45	Mariam Daoud, Lynda Tamine-Lechani, Mohand Boughanem	Using a graph-based ontological user profile for personalizing search.	CIKM	2008	DBLP DOI BibTeX RDF	graph based user profile, session boundary recognition, ontology, personalization
44	Rui Song, Enhong Chen, Min Zhao	SVM Based Automatic User Profile Construction for Personalized Search.	ICIC (1)	2005	DBLP DOI BibTeX RDF
44	Xujuan Zhou, Sheng-Tang Wu, Yuefeng Li, Yue Xu 0001, Raymond Y. K. Lau, Peter D. Bruza	Utilizing Search Intent in Topic Ontology-Based User Profile for Web Mining.	Web Intelligence	2006	DBLP DOI BibTeX RDF
43	Annika Wærn	User Involvement in Automatic Filtering: An Experimental Study.	User Model. User Adapt. Interact.	2004	DBLP DOI BibTeX RDF	recommender systems, information filtering, experimental study, user involvement, personal profile
42	Angela Carrillo Ramos, Marlène Villanova-Oliver, Jérôme Gensel, Hervé Martin	Contextual User Profile for Adapting Information in Nomadic Environments.	WISE Workshops	2007	DBLP DOI BibTeX RDF	adaptation, mobile device, user profile, preferences, context of use
41	Sofia Tsekeridou	Metadata and user profile model for personalized enhanced DTV multi-service access.	ICIP (3)	2005	DBLP DOI BibTeX RDF
41	Lin Li 0001, Zhenglu Yang, Botao Wang, Masaru Kitsuregawa	Dynamic Adaptation Strategies for Long-Term and Short-Term User Profile to Personalize Search.	APWeb/WAIM	2007	DBLP DOI BibTeX RDF
40	Yoshinori Hijikata, Kazuhiro Iwahama, Shogo Nishida	Content-based music filtering system with editable user profile.	SAC	2006	DBLP DOI BibTeX RDF	decision tree, user profile, customization, content-based filtering, music recommendation
37	Domenico Rosaci, Giuseppe M. L. Sarnè	MASHA: A multi-agent system handling user and device adaptivity of Web sites.	User Model. User Adapt. Interact.	2006	DBLP DOI BibTeX RDF	Web adaptivity, Device adaptivity, Recommender systems, Information agents
37	Tarek Helmy, Tsunenori Mine, Makoto Amamiya	Adaptive Exploiting User Profile and Interpretation Policy for Searching and Browsing the Web on KODAMA System.	DEXA Workshops	2000	DBLP DOI BibTeX RDF	adaptive exploitation, interpretation policy, KODAMA system, KODAMA research project, hyper-link structure, interpretation policies, online distributed relevant information retrieval, user interface agents, personalized information filtering, adaptive autonomous user interface agent, Web page agents, server agents, World Wide Web, user profile, interface agents, agent community, information resources, information needs
36	Daisuke Morikawa, Masaru Honjo, Akira Yamaguchi, Satoshi Nishiyama, Masayoshi Ohashi	Cell-Phone Based User Activity Recognition, Management and Utilization.	MDM	2006	DBLP DOI BibTeX RDF
36	JinHong Kim, EunSeok Lee 0001	XFCM - XML Based on Fuzzy Clustering and Merging - Method for Personalized User Profile Based on Recommendation System of Category and Product.	AWCC	2004	DBLP DOI BibTeX RDF
34	Jeongyeon Lim, Munjo Kim, Bumshik Lee, Munchurl Kim, Heekyung Lee, Hankyu Lee	A target advertisement system based on TV viewer's profile reasoning.	Multim. Tools Appl.	2008	DBLP DOI BibTeX RDF	Target advertisement, Personalcasting, User profile reasoning
34	Yabo Xu, Ke Wang 0001, Benyu Zhang, Zheng Chen 0001	Privacy-enhancing personalized web search.	WWW	2007	DBLP DOI BibTeX RDF	hierarchical user profile, privacy, personalized search
34	Vincent Wenchen Zheng, Yu Zheng 0004, Qiang Yang 0001	Joint learning user's activities and profiles from GPS data.	GIS-LBSN	2009	DBLP DOI BibTeX RDF	user profile learning, GPS, activity recognition
34	U. Rohini, Vamshi Ambati	Improving Re-ranking of Search Results Using Collaborative Filtering.	AIRS	2006	DBLP DOI BibTeX RDF
33	Sung-Hyon Myaeng, Robert R. Korfhage	Dynamic user profile in information retrieval (abstract only).	ACM Conference on Computer Science	1985	DBLP DOI BibTeX RDF
33	Naveed Mushtaq, Peter Werner, Karsten Tolle, Roberto V. Zicari	Building and Evaluating Non-Obvious User Profiles for Visitors of Web Sites.	CEC	2004	DBLP DOI BibTeX RDF	Non-obvious user profile, Web page ranking, Feedback mechanism
33	Tsvi Kuflik, Peretz Shoval	Generation of user profiles for information filtering - research agenda.	SIGIR	2000	DBLP DOI BibTeX RDF	rule-based filtering, user profile, information filtering, content-based filtering
32	Diana Weiß, Johannes Scheuerer, Michael Wenleder, Alexander Erk, Mark Gülbahar, Claudia Linnhoff-Popien	A user profile-based personalization system for digital multimedia content.	DIMEA	2008	DBLP DOI BibTeX RDF	multimedia, recommendation system, personalization, profiling
31	Huan Wang, Xiaomin Shi, Yan Li, Heng Chang, Weiliang Chen, Jie Tang, Eduardo Martins	User Profile Management for Personalized Telecom Service.	ICYCS	2008	DBLP DOI BibTeX RDF
31	Stefan Uhlmann, Artur Lugmayr	Personalization algorithms for portable personality.	MindTrek	2008	DBLP DOI BibTeX RDF	ubiquitous computing, personalization, user profile, portable
31	Verus Pronk, Wim F. J. Verhaegh, Adolf Proidl, Marco Tiemann	Incorporating user control into recommender systems based on naive bayesian classification.	RecSys	2007	DBLP DOI BibTeX RDF	multi-valued features, machine learning, classification, user profile, recommender, naive Bayes, user control
31	Michael Sutterer, Olaf Droegehorn, Klaus David	Making a case for situation-dependent user profiles in context-aware environments.	MNCNA	2007	DBLP DOI BibTeX RDF	context-awareness, personalization, user profile, situation
30	Françoise Petersen, Giovanni Bartolomeo, Mike Pluke, Tatiana Kovacikova	An architectural framework for context sensitive personalization: standardization work at the European Telecommunications Standards Institute (ETSI).	Mobility Conference	2009	DBLP DOI BibTeX RDF	personalization, interoperability, user profile, next generation network (NGN)
30	Rebecca Cathey, Ling Ma 0001, Nazli Goharian, David A. Grossman	Misuse detection for information retrieval systems.	CIKM	2003	DBLP DOI BibTeX RDF	clustering, information retrieval, relevance feedback, user profile, misuse detection
30	Nikolaos Nanas, Manolis Vavalis, Anne N. De Roeck	A network-based model for high-dimensional information filtering.	SIGIR	2010	DBLP DOI BibTeX RDF	content-based information filtering, user profiling, curse of dimensionality
30	Tsvi Kuflik, Bracha Shapira, Yuval Elovici, Adlai Maschiach	Privacy Preservation Improvement by Learning Optimal Profile Generation Rate.	User Modeling	2003	DBLP DOI BibTeX RDF
29	Lyes Limam	Usage-driven unified model for user profile and data source profile extraction. (Model unifié dérigé par l'usage pour l'extraction du profile de l'utilisateur et de la source de donnée).		2014	RDF
29	Corinne Amel Zayani, André Péninou, C. Marie-Françoise Canut, Florence Sèdes	An Adaptation Approach: Query Enrichment by User Profile.	SITIS	2006	DBLP DOI BibTeX RDF
29	Sofia Tsekeridou	MPEG-7 MDS-Based Application Specific Metadata Model for Personalized Multi-Service Access in a DTV Broadcast Environment.	ICME	2005	DBLP DOI BibTeX RDF
29	Gabriel Somlo, Adele E. Howe	Using web helper agent profiles in query generation.	AAMAS	2003	DBLP DOI BibTeX RDF	user modeling, information agents, query generation
29	Kyung-Yong Jung	User Preference Through Learning User Profile for Ubiquitous Recommendation Systems.	KES (1)	2006	DBLP DOI BibTeX RDF
28	Judy Kay, Bob Kummerfeld, Piers Lauder	Personis: A Server for User Models.	AH	2002	DBLP DOI BibTeX RDF	Server for user profile/model, Security and Privacy of User Models, User Modelling, Personalisation, User Control
28	Ioannis Panagiotopoulos, Lambrini Seremeti, Achilles Kameas	An Alignable User Profile Ontology for Ambient Intelligence Environments.	Intelligent Environments	2011	DBLP DOI BibTeX RDF	activity spheres, ontologies, user profile, ambient intelligence
28	Lo Ka Kan, Xiang Peng, Irwin King	A user profile-based approach for personal information access: shaping your information portfolio.	WWW	2006	DBLP DOI BibTeX RDF	internet behavior, information retrieval, user profile, system, personal information access
27	Ibrahim Cingil	Supporting Global User Profiles Through Trusted Authorities.	SIGMOD Rec.	2002	DBLP DOI BibTeX RDF
27	Dingming Wu 0002, Dongyan Zhao 0001, Xue Zhang	An Adaptive User Profile Based on Memory Model.	WAIM	2008	DBLP DOI BibTeX RDF
27	Dongling Chen, Daling Wang, Ge Yu 0001, Fang Yu	A PLSA-Based Approach for Building User Profile and Implementing Personalized Recommendation.	APWeb/WAIM	2007	DBLP DOI BibTeX RDF
27	Jue Wang, Zhiwei Li 0006, Jinyi Yao, Zengqi Sun, Mingjing Li, Wei-Ying Ma	Adaptive User Profile Model and Collaborative Filtering for Personalized News.	APWeb	2006	DBLP DOI BibTeX RDF
27	Anaelis Sesin, Malek Adjouadi, Mercedes Cabrerizo, Melvin Ayala, Armando Barreto	An Eye Gaze Tracking System Using Customized User Profiles to Help Persons with Motor Challenges Access Computers.	ICCHP	2008	DBLP DOI BibTeX RDF	Eye-gaze tracking system, artificial neural network, user profile, jitter
27	Sendhilkumar Selvaraju, T. V. Geetha	Personalized ontology for web search personalization.	Bangalore Compute Conf.	2008	DBLP DOI BibTeX RDF	architecture, personalization, web search, user profile, personalized ontology
26	Shiliang Zhang, Qingming Huang, Qi Tian 0001, Shuqiang Jiang, Wen Gao 0001	Personalized MTV Affective Analysis Using User Profile.	PCM	2008	DBLP DOI BibTeX RDF	Affective Content Analysis, Dimensional Affective Model, Personalized Affective Analysis, Support Vector Regression
26	Ugo Galassi, Attilio Giordana, Dino Mendola	Learning User Profile from Traces.	SAINT Workshops	2005	DBLP DOI BibTeX RDF
26	Giuseppe Amato 0001, Umberto Straccia	User Profile Modeling and Applications to Digital Libraries.	ECDL	1999	DBLP DOI BibTeX RDF
26	Xiaowei Shi	An Intelligent Knowledge-Based Recommendation System.	Intelligent Information Processing	2004	DBLP DOI BibTeX RDF	Metadata, Knowledge Representation, User profile, Recommendation, Multi-agent
26	Angela Carrillo Ramos, Marlène Villanova-Oliver, Jérôme Gensel, Hervé Martin	Profiling Nomadic Users Considering Preferences and Context of Use.	OTM Workshops (1)	2007	DBLP DOI BibTeX RDF	adaptation, mobile device, user profile, preferences, context of use
25	Hassan Naderi, Béatrice Rumpler, Jean-Marie Pinon	An Efficient Collaborative Information Retrieval System by Incorporating the User Profile.	Adaptive Multimedia Retrieval	2006	DBLP DOI BibTeX RDF	personalized collaborative information retrieval, Information retrieval, personalization
25	Blaise W. Liffick, Gary M. Zoppetti	You can take it with you: profile transportability.	ITiCSE	2007	DBLP DOI BibTeX RDF	assistive technology, user profile
25	Blaise W. Liffick, Gary M. Zoppetti, Shane Shearer	The personal portable profile project.	ASSETS	2006	DBLP DOI BibTeX RDF	assistive technology, user profile
25	Jiaqian Zheng, Jing Yao, Junyu Niu	Web user de-identification in personalization.	WWW	2008	DBLP DOI BibTeX RDF	de-identification, user profile, domain
25	Vesa Kantola, Sauli Tiitta, Katri Mehto, Tomi Kankainen	Using dramaturgical methods to gain more dynamic user understanding in user-centered design.	Creativity & Cognition	2007	DBLP DOI BibTeX RDF	dramaturgical methods, interactive theater, role character, visualization, user-centered design, user profile, design methodology, persona, drama
25	Ed Huai-hsin Chi, Adam Rosien, Jeffrey Heer	LumberJack: Intelligent Discovery and Analysis of Web User Traffic Composition.	WEBKDD	2002	DBLP DOI BibTeX RDF	Clustering, World Wide Web, Web Mining, User Profile, Log Analysis, User Sessions
25	Alberto Díaz Esteban	Integrating Multilingual Text Classification Tasks and User Modeling in Personalized Newspaper Services.	User Modeling	2001	DBLP DOI BibTeX RDF	Short/long-term models, multi-topic user profile, adaptive user model, multilingual text classification tasks, evaluation
25	Oscar Díaz, Salvador Trujillo, Sandy Pérez	Turning portlets into services: the consumer profile.	WWW	2007	DBLP DOI BibTeX RDF	SOA, adaptability, portals, product lines, portlets, WSRP
25	Silvia N. Schiaffino, Analía Amandi	Intelligent User Profiling.	Artificial Intelligence: An International Perspective	2009	DBLP DOI BibTeX RDF
24	Hoda Sepehri Rad, Caro Lucas	On the Effectiveness of Prioritized User-Profile and Detecting Active Users in Collaborative Filtering Recommender Systems.	ICDE Workshops	2007	DBLP DOI BibTeX RDF
24	Rachid Arezki, Pascal Poncelet, Gérard Dray, David William Pearson	Information Retrieval Model Based on User Profile.	AIMSA	2004	DBLP DOI BibTeX RDF
24	Kyung-Yong Jung, Kee-Wook Rim, Jung-Hyun Lee	Automatic Preference Mining through Learning User Profile with Extracted Information.	SSPR/SPR	2004	DBLP DOI BibTeX RDF
24	Hassan Naderi, Béatrice Rumpler, Jean-Marie Pinon	A graph-based profile similarity calculation method for collaborative information retrieval.	SAC	2008	DBLP DOI BibTeX RDF	collaborative information retrieval (CIR), dynamic community, profile similarity, user profile
24	Hassan Naderi, Béatrice Rumpler	Graph-Based Profile Similarity Calculation Method and Evaluation.	ECIR	2008	DBLP DOI BibTeX RDF	CIR, profile similarity, dynamic community creation, User profile
24	Konstantinos Raftopoulos, Nikolaos Papadakis, Klimis S. Ntalianis, Stefanos D. Kollias	Semantic clustering of information systems' users with stochastic techniques.	ICSC	2007	DBLP DOI BibTeX RDF	User profile clustering, Markovian state clustering, semantic clustering
24	Klaus-Dieter Schewe, Roland H. Kaschek, Claire Matthews, Catherine Wallace	Modelling Web-Based Banking Systems: Story Boarding and User Profiling.	ER (Workshops)	2002	DBLP DOI BibTeX RDF	user profile, e-business, Banking, story boarding
24	Julie A. Jacko, Holly S. Vitense	A review and reappraisal of information technologies within a conceptual framework for individuals with disabilities.	Univers. Access Inf. Soc.	2001	DBLP DOI BibTeX RDF	User profile, Disabilities, Conceptual framework
24	Manuel de Buenaga Rodríguez, Manuel J. Maña López, Alberto Díaz Esteban, Pablo Gervás Gómez-Navarro	A User Model Based on Content Analysis for the Intelligent Personalization of a News Service.	User Modeling	2001	DBLP DOI BibTeX RDF	short/long-term models, multi-topic user profile, adaptive user model, personalized information service, Information dissemination
23	Jianguo Pan, Bofeng Zhang, Shufeng Wang, Gengfeng Wu, Daming Wei	Ontology Based User Profiling in Personalized Information Service Agent.	CIT	2007	DBLP DOI BibTeX RDF
23	Michael J. Pazzani, Daniel Billsus	Content-Based Recommendation Systems.	The Adaptive Web	2007	DBLP DOI BibTeX RDF
23	Byron L. D. Bezerra, Francisco de A. T. de Carvalho, Geber L. Ramalho, Jean-Daniel Zucker	Speeding up Recommender Systems with Meta-prototypes.	SBIA	2002	DBLP DOI BibTeX RDF
23	Bhavani Raskutti, Anthony Beitz, Belinda Ward	A Feature-based Approach to Recommending Selections based on Past Preferences.	User Model. User Adapt. Interact.	1997	DBLP DOI BibTeX RDF	personalised recommendations, acquisition of individual user models, information filtering, interactive services
23	Yasufumi Takama, Yuki Muto	Mining User Preference Model from Utterances.	Foundations of Computational Intelligence (6)	2009	DBLP DOI BibTeX RDF
23	Fang Liu 0019, Clement T. Yu, Weiyi Meng	Personalized Web Search For Improving Retrieval Effectiveness.	IEEE Trans. Knowl. Data Eng.	2004	DBLP DOI BibTeX RDF	Category hierarchy, personalization, search engine, information filtering, retrieval effectiveness
23	Seon-Mi Woo, Chun-Sik Yoo	Digital Library Retrieval Model Using Subject Classification Table and User Profile.	ICADL	2004	DBLP DOI BibTeX RDF
23	Ihn-Han Bae	A Rough Set Based Anomaly Detection Scheme Considering the Age of User Profiles.	International Conference on Computational Science (4)	2007	DBLP DOI BibTeX RDF	Rough Set, Anomaly Detection, User Profile, Age
23	Bernard Mérialdo, Kyung Tak Lee, Dario Luparello, Jeremie Roudaire	Automatic construction of personalized TV news programs.	ACM Multimedia (1)	1999	DBLP DOI BibTeX RDF	personalization, user profile, information filtering, multimedia indexing, video summary
22	W. Kosinski, D. Kowalczyk	Adaptive Decision Support System Using Web-Users Profile Data.	AWIC	2007	DBLP DOI BibTeX RDF
22	Fang Liu 0019, Clement T. Yu, Weiyi Meng	Personalized web search by mapping user queries to categories.	CIKM	2002	DBLP DOI BibTeX RDF	category hierarchy, personalization, search engine, information filtering
22	Michael Sutterer, Olaf Droegehorn, Klaus David	UPOS: User Profile Ontology with Situation-Dependent Preferences Support.	ACHI	2008	DBLP DOI BibTeX RDF	ontology, user modeling, Context-aware system, situation
22	Byron L. D. Bezerra, Francisco de A. T. de Carvalho, Valmir Macário Filho	C^2: : A Collaborative Recommendation System Based on Modal Symbolic User Profile.	Web Intelligence	2006	DBLP DOI BibTeX RDF
22	Seong-Yoon Shin, Oh-Hyung Kang, Seong-Eun Baek, Ki-Hong Park, Yang-Won Rhee, Moonhaeng Huh	A Real-Time Evaluation System for Acquisition of Certificates in Computer Skills.	ICCSA (1)	2007	DBLP DOI BibTeX RDF	Easy-to-access Active Learning System, User Profile, Evaluation System
22	Abdallah Mhamed, Cecilia Fred, Arab Farah	An Authentication Architecture Dedicated to Dependent People in Smart Environments.	ICOST	2007	DBLP DOI BibTeX RDF	dependent people, security, authentication, Pervasive computing, biometrics, user profile, smart home
21	Tapan Kamdar, Anupam Joshi	Using incremental Web log mining to create adaptive web servers.	Int. J. Digit. Libr.	2005	DBLP DOI BibTeX RDF	Data mining, Personalization, E-commerce, Web mining, Fuzzy clustering
21	Yi Cai 0001, Qing Li 0001, Haoran Xie 0001, Lijuan Yu	Personalized Resource Search by Tag-Based User Profile and Resource Profile.	WISE	2010	DBLP DOI BibTeX RDF
21	Yi Cai 0001, Qing Li 0001	Personalized search by tag-based user profile and resource profile in collaborative tagging systems.	CIKM	2010	DBLP DOI BibTeX RDF
21	Seon-Mi Woo, Chun-Sik Yoo, Yong-Sung Kim	Adaptive Filtering and Document Ranking using User Profile and Group Profile.	IC-AI	1999	DBLP BibTeX RDF
21	Michael Sutterer, Olaf Droegehorn, Klaus David	User Profile Management on Service Platforms for Ubiquitous Computing Environments.	VTC Spring	2007	DBLP DOI BibTeX RDF
21	Alan Eckhardt, Tomás Horváth, Peter Vojtás	PHASES: A User Profile Learning Approach for Web Search.	Web Intelligence	2007	DBLP DOI BibTeX RDF
21	Manuel F. Gomes Junior, Anne M. P. Canuto	Carcara: A Multi-agent System for Web Mining Using Adjustable User Profile and Dynamic Grouping.	IAT	2006	DBLP DOI BibTeX RDF
21	Mohit Goel, Sudeshna Sarkar	Web Site Personalization Using User Profile Information.	AH	2002	DBLP DOI BibTeX RDF
21	Agnieszka Lewandowska, Cezary Mazurek, Marcin Werla	Enrichment of European Digital Resources by Federating Regional Digital Libraries in Poland.	ECDL	2008	DBLP DOI BibTeX RDF	digital libraries federation, coordination of digitization, atomic services, digital object identifiers resolution, networked user profile, metadata harvesting
21	Jun'ichi Miyao, Shi-Kuo Chang	A Framework of a Visual Language with Dynamic Specification.	VL	1995	DBLP DOI BibTeX RDF	dynamic specification, complex software behavior, object oriented visual language, formal specification, time, user profile, visual programming, visual languages, visual language, object-oriented languages, snapshot, overlap, sweep, visualized specification, dynamic objects, input data
20	Riddhiman Ghosh, Mohamed Dekhil	Discovering user profiles.	WWW	2009	DBLP DOI BibTeX RDF	semantic web, personalization, user profiles, information management
20	Krishnan Ramanathan, Komal Kapoor	Creating User Profiles Using Wikipedia.	ER	2009	DBLP DOI BibTeX RDF	DMOZ, Evaluation, Personalization, User modeling, Wikipedia, User profiles, Hierarchy
20	Thomas Kleemann, Alex Sinner	Decision Support for Personalization on Mobile Devices.	ICLP	2005	DBLP DOI BibTeX RDF
20	Halima Habieb-Mammar, Franck Tarpin-Bernard, Patrick Prévôt	Adaptive Presentation of Multimedia Interface Case Study: "Brain Story" Course.	User Modeling	2003	DBLP DOI BibTeX RDF