Search results for "Template"

Hits ?▲	Authors	Title	Venue	Year	Link	Author keywords
75	Hang Su, Qiaozhu Mei	Template extraction from candidate template set generation: a structure and content approach.	ACM Southeast Regional Conference (2)	2005	DBLP DOI BibTeX RDF	candidate template set, table informativeness, template extraction, structure similarity
70	Stephen Karungaru, Minoru Fukumi, Norio Akamatsu, Takuya Akashi	A Simple 3D Edge Template for Pose Invariant Face Detection.	KES (3)	2006	DBLP DOI BibTeX RDF	3D edge template, bezier curves and template matching, genetic algorithms
69	Florian Heidenreich, Jendrik Johannes, Mirko Seifert, Christian Wende, Marcel Böhme	Generating safe template languages.	GPCE	2009	DBLP DOI BibTeX RDF	safe authoring, template language, generative programming, language extension
67	Shinichiro Omachi, Masako Omachi	Fast Template Matching With Polynomials.	IEEE Trans. Image Process.	2007	DBLP DOI BibTeX RDF
60	Katsushi Ikeuchi, Takeshi Shakunaga, Mark D. Wheeler, Taku Yamazaki	Invariant histograms and deformable template matching for SAR target recognition.	CVPR	1996	DBLP DOI BibTeX RDF	radar target recognition, invariant histograms, deformable template matching, SAR target recognition, model-based vision technique, multi-step deformable template matching, potential energy field, background signatures, image matching, synthetic aperture radar, synthetic-aperture radar, geometric features, radar imaging
58	Terence John Parr	Enforcing strict model-view separation in template engines.	WWW	2004	DBLP DOI BibTeX RDF	template engine, web application, model-view-controller
57	A. Kohandani, Otman A. Basir, Mohamed S. Kamel	A Fast Algorithm for Template Matching.	ICIAR (2)	2006	DBLP DOI BibTeX RDF
57	Xiaoping Liu 0003, Hui Shi, Zhengqiang Mao, Liping Zheng	Cooperative Template Mechanism for Cooperative Design.	CSCWD (Selected papers)	2005	DBLP DOI BibTeX RDF
53	Michiaki Tatsubori, Toyotaro Suzumura	HTML templates that fly: a template engine approach to automated offloading from server to client.	WWW	2009	DBLP DOI BibTeX RDF	client-server partitioning, template engines, web applications
53	Yi Cheng Feng, Pong Chi Yuen	Selection of Distinguish Points for Class Distribution Preserving Transform for Biometric Template Protection.	ICB	2007	DBLP DOI BibTeX RDF	Biometric template security, one-way transform, class distribution preserving, face recognition
53	Jerome L. Paul, Michal Kouril, Kenneth A. Berman	A template library to facilitate teaching message passing parallel computing.	SIGCSE	2006	DBLP DOI BibTeX RDF	teaching aid, template library, parallel processing, MPI, SAT, beowulf clusters
53	Hanchuan Peng, Fuhui Long, Zheru Chi	Document Image Recognition Based on Template Matching of Component Block Projections.	IEEE Trans. Pattern Anal. Mach. Intell.	2003	DBLP DOI BibTeX RDF	Document image recognition, component block projection, template matching
53	Qing X. Wu	A Correlation-Relaxation-Labeling Framework for Computing Optical Flow - Template Matching from a New Perspective.	IEEE Trans. Pattern Anal. Mach. Intell.	1995	DBLP DOI BibTeX RDF	cloud motion fields, motion estimation, Optical flow, template matching, cross-correlation, relaxation labeling, dynamic scene analysis
52	Bin Liu, Ning Shangguan, Junyi Lin, Kaiyong Jiang	Transferring Landmarks to Individual Foot Using Deformable Template Models.	ICYCS	2008	DBLP DOI BibTeX RDF
52	Tony X. Han, Visvanathan Ramesh, Ying Zhu, Thomas S. Huang	On Optimizing Template Matching via Performance Characterization.	ICCV	2005	DBLP DOI BibTeX RDF
52	Haim Schweitzer, J. W. Bell, Feng Wu	Very Fast Template Matching.	ECCV (4)	2002	DBLP DOI BibTeX RDF
51	Peter Sussner, Gerhard X. Ritter	Decomposition of Gray-Scale Morphological Templates Using the Rank Method.	IEEE Trans. Pattern Anal. Mach. Intell.	1997	DBLP DOI BibTeX RDF	morphological template, template decomposition, template rank, convolution, Morphology, structuring element
51	Ricardo López, Thomas S. Huang	3D head pose computation from 2D images: templates versus features.	ICIP	1995	DBLP DOI BibTeX RDF	3D head pose computation, 3-D human head pose, 2-D gray scale images, human head modeling, model based video compression, 3D head tracking, 3D object alignment, 2D template regions, feature point approach, template method, input facial region, template database, head scales, image segmentation, feature extraction, face recognition, face recognition, tracking, data compression, image sequences, image sequences, video coding, image matching, 3D model, polyhedrons, 2D images, facial features, cubes, polyhedral objects, head orientations
48	Karane Vieira, André Luiz da Costa Carvalho, Klessius Berlt, Edleno Silva de Moura, Altigran Soares da Silva, Juliana Freire	On Finding Templates on Web Collections.	World Wide Web	2009	DBLP DOI BibTeX RDF	web template detection, tree-mapping, web IR
48	Tsaipei Wang	Possibilistic C-Template Clustering and Its Application in Object Detection in Images.	PSIVT	2006	DBLP DOI BibTeX RDF	Shell clustering, Possibilistic clustering, Object and shape Detection, Template-based methods, Fuzzy clustering, Robust clustering
46	Junfeng Wang, Xiaofei He 0001, Can Wang 0001, Jian Pei, Jiajun Bu, Chun Chen 0001, Ziyu Guan, Gang Lu	News article extraction with template-independent wrapper.	WWW	2009	DBLP DOI BibTeX RDF	data extraction
46	Chen Zhang, Julian Eggert, Nils Einecke	Robust Tracking by Means of Template Adaptation with Drift Correction.	ICVS	2009	DBLP DOI BibTeX RDF
46	Keiji Sakabe, Tomoyuki Taguchi, Takeshi Shakunaga	Automatic Eigentemplate Learning for Sparse Template Tracker.	PSIVT	2009	DBLP DOI BibTeX RDF
46	Pei Wu, Xianbin Cao 0001, Yanwu Xu 0001, Hong Qiao	Representative Template Set Generation Method for Pedestrian Detection.	FSKD (4)	2008	DBLP DOI BibTeX RDF
46	Biagio Freni, Gian Luca Marcialis, Fabio Roli	Online and Offline Fingerprint Template Update Using Minutiae: An Experimental Comparison.	AMDO	2008	DBLP DOI BibTeX RDF
46	Biagio Freni, Gian Luca Marcialis, Fabio Roli	Replacement Algorithms for Fingerprint Template Update.	ICIAR	2008	DBLP DOI BibTeX RDF
46	Elisabeth Oswald, Stefan Mangard	Template Attacks on Masking - Resistance Is Futile.	CT-RSA	2007	DBLP DOI BibTeX RDF
46	Kai Mertins, Markus Rabe 0001, Frank-Walter Jaekel	Neutral template libraries for efficient distributed simulation within a manufacturing system engineering platform.	WSC	2000	DBLP DOI BibTeX RDF
46	Toshimitsu Kaneko, Osamu Hori	Template Update Criterion for Template Matching of Image Sequences.	ICPR (2)	2002	DBLP DOI BibTeX RDF
44	Christian Kohlschütter	A densitometric analysis of web template content.	WWW	2009	DBLP DOI BibTeX RDF	template removal, content analysis, noise removal, web page segmentation, template detection
44	Gian Luca Marcialis, Ajita Rattani, Fabio Roli	Biometric Template Update: An Experimental Investigation on the Relationship between Update Errors and Performance Degradation in Face Verification.	SSPR/SPR	2008	DBLP DOI BibTeX RDF	Template update, Intra-class variations, Face biometrics, template update errors, Biometrics, impostors, threshold selection
44	David W. Paglieroni, Gary E. Ford, Eric M. Tsujimoto	The Position-Orientation Masking Approach to Parametric Search for Template Matching.	IEEE Trans. Pattern Anal. Mach. Intell.	1994	DBLP DOI BibTeX RDF	position-orientation masking, edge segments matching, template vertices, image vertices, binary decomposition, quadrant decomposition, edge detection, transforms, correlations, search problems, template matching, distance transforms, correlation methods, parametric search
43	Soji Yamakawa, Kenji Shimada	HEXHOOP: Modular Templates for Converting a Hex-Dominant Mesh to an ALL-Hex Mesh.	Eng. Comput.	2002	DBLP DOI BibTeX RDF	Hex-dominant, Mesh conversion, Template, Pyramid, Hexahedral mesh
43	Attila Fazekas	Skeletonization on Orojection Pictures.	CAIP	1999	DBLP DOI BibTeX RDF	template method, projection picture, Skeletonization
42	Frédéric J. P. Richard, Adeline M. M. Samson, Charles-André Cuenod	A SAEM algorithm for the estimation of template and deformation parameters in medical image sequences.	Stat. Comput.	2009	DBLP DOI BibTeX RDF	SAEM algorithm, Medical image sequence, Template estimation, Image registration, Image denoising
42	Mohammad Osiur Rahman, Aini Hussain, Edgar Scavino, M. A. Hannan, Hassan Basri	Recyclable Waste Paper Sorting Using Template Matching.	IVIC	2009	DBLP DOI BibTeX RDF	Waste Paper Sorting, Grades of Paper, Template matching
42	Sufian Sudeng, Arthit Thongtak	Template Based: A Novel STG Based Logic Synthesis for Asynchronous Control Circuits.	World Congress on Engineering (Selected Papers)	2008	DBLP DOI BibTeX RDF	asynchronous control circuits, asynchronous DMA controller, template based technique, logic synthesis, Signal Transition Graph (STG)
42	Francisco J. García Izquierdo, Raúl Izquierdo Castanedo, Aquilino A. Juan Fuente	A Double-Model Approach to Achieve Effective Model-View Separation in Template Based Web Applications.	ICWE	2007	DBLP DOI BibTeX RDF	template systems, software architectures, Web applications, MVC
42	Ryo Ohtera, Takahiko Horiuchi, Shoji Tominaga	Eye-Gaze Detection from Monocular Camera Image Using Parametric Template Matching.	ACCV (1)	2007	DBLP DOI BibTeX RDF	Eyegaze Detection, Parametric template matching, Eyeball model, Eyegaze Keyboard
42	Hae Yong Kim, Sidnei Alves de Araújo	Grayscale Template-Matching Invariant to Rotation, Scale, Translation, Brightness and Contrast.	PSIVT	2007	DBLP DOI BibTeX RDF	RST-invariance, segmentation-free shape recognition, Template matching
42	C. L. Li, Kin Chuen Hui	A Template-Matching Approach to Free-Form Feature Recognition.	IV	2000	DBLP DOI BibTeX RDF	free form features, template matching, Feature recognition
42	Torsten Rohlfing, Edith V. Sullivan, Adolf Pfefferbaum	Subject-Matched Templates for Spatial Normalization.	MICCAI (1)	2009	DBLP DOI BibTeX RDF
42	Jinbo Xu	Fold Recognition by Predicted Alignment Accuracy.	IEEE ACM Trans. Comput. Biol. Bioinform.	2005	DBLP DOI BibTeX RDF	protein fold recognition, SVM regression, Protein structure prediction, protein threading
41	Michael Derntl, Susanne Neumann, Petra Oberhuemer	Constructing and Evaluating a Description Template for Teaching Methods.	EC-TEL	2009	DBLP DOI BibTeX RDF
41	Junfeng Wang, Chun Chen 0001, Can Wang 0001, Jian Pei, Jiajun Bu, Ziyu Guan, Wei Vivian Zhang	Can we learn a template-independent wrapper for news article extraction from a single training site?	KDD	2009	DBLP DOI BibTeX RDF	classification, web mining, data extraction
41	Sriram Sankaranarayanan 0001, Thao Dang 0001, Franjo Ivancic	Symbolic Model Checking of Hybrid Systems Using Template Polyhedra.	TACAS	2008	DBLP DOI BibTeX RDF
41	Alexander Sibiryakov	Statistical Template Matching under Geometric Transformations.	DGCI	2008	DBLP DOI BibTeX RDF
41	Jiyan Pan, Bo Hu 0002	Robust Object Tracking Against Template Drift.	ICIP (3)	2007	DBLP DOI BibTeX RDF
41	Julian Eggert, Chen Zhang, Edgar Körner	Template Matching for Large Transformations.	ICANN (2)	2007	DBLP DOI BibTeX RDF
41	Jianwei Niu 0001, Joanne M. Atlee, Nancy A. Day	Template Semantics for Model-Based Notations.	IEEE Trans. Software Eng.	2003	DBLP DOI BibTeX RDF	Model-based specification notations, automated generation of analysis tools, semantics, concurrency, composition
41	Kimmo Fredriksson, Esko Ukkonen	Faster template matching without FFT.	ICIP (1)	2001	DBLP DOI BibTeX RDF
41	Xiaoping Liu, Xiao-Yun Liu, Zheng-Feng Hou, Xiao-Rong Du	Research on Cooperative Template Design.	CSCWD	2001	DBLP DOI BibTeX RDF
41	Boyan A. Onyshkevych	Template design for information extraction.	MUC	1993	DBLP DOI BibTeX RDF
40	Roland Weiss, Volker Simonis	Exploring Template Template Parameters.	Ershov Memorial Conference	2001	DBLP DOI BibTeX RDF
39	Bian Yang, Christoph Busch 0001, Mohammad Omar Derawi, Patrick Bours, Davrondzhon Gafurov	Geometric-Aligned Cancelable Fingerprint Templates.	ICIAP	2009	DBLP DOI BibTeX RDF	cancelable fingerprint template, fingerprint alignment, coordinate encryption, template protection
39	Ajit Singh, Jonathan Schaeffer, Mark Green 0001	A Template-Based Approach to the Generation of Distributed Applications Using a Network of Workstations.	IEEE Trans. Parallel Distributed Syst.	1991	DBLP DOI BibTeX RDF	distributed applications generation, template-based approach, RPC model, template attachment, sequential procedures, low-level code, correct synchronization, Unix-based workstation environments, scheduling, software engineering, parallel programming, distributed processing, programming environments, computational model, network of workstations, communication behavior
38	Wei-Yun Yau, Kar-Ann Toh, Tai Pang Chen	Fingerprint Templates Combination.	SINOBIOMETRICS	2004	DBLP DOI BibTeX RDF	fingerprint template combination, minutiae data transformation, fingerprint recognition
38	Yuanqing Guo, Gerard J. M. Smit, Hajo Broersma, Paul M. Heysters	A graph covering algorithm for a coarse grain reconfigurable system.	LCTES	2003	DBLP DOI BibTeX RDF	template generation, compiler, reconfigurable system
38	Ying Dong, Mingshu Li 0001	TEMPPLET: A New Method for Domain-Specific Ontology Design.	EDCIS	2002	DBLP DOI BibTeX RDF	Ontology, template, domain, applet
38	Stefan Huwer, Heinrich Niemann	2D-Object Tracking Based on Projection-Histograms.	ECCV (1)	1998	DBLP DOI BibTeX RDF	2D-tracking, template matching, real-time tracking
37	Anwar Manzar, Tanweer Ahmad Cheema, Ijaz Mansoor Qureshi	New scale invariant template matching technique using hyper space image representation.	Pattern Anal. Appl.	2009	DBLP DOI BibTeX RDF	Hyper-vectors, Template matching, Radon transform, Scale-invariant, Edge matching
37	Loris Gaio, Matthijs den Besten, Alessandro Rossi 0001, Jean-Michel Dalle	Wikibugs: using template messages in open content collections.	Int. Sym. Wikis	2009	DBLP DOI BibTeX RDF	bug fixing, commons based peer production, template messages, coordination, Wiki, quality, Wikipedia, survival analysis
37	Chorng-Shiuh Koong, Ching-Meng Lee, Deng-Jyi Chen, Chih-Hung Chang, Chihhsiong Shih	The visual authoring tool of flash-based component for interactive item template.	SAC	2009	DBLP DOI BibTeX RDF	SWF component, interactive item, item template, visual authoring tool, reuse, software component
37	Chang-Mug Lee, Kwang-Ho Seok, Yoon Sang Kim, Oh-Young Kwon	Automatic motion creating from the posture template for the robot physical training system.	ICHIT	2009	DBLP DOI BibTeX RDF	motion creation, motion transform, template matching
37	Gyeongdong Baek, Sungshin Kim	Two Step Template Matching Method with Correlation Coefficient and Genetic Algorithm.	ICIC (2)	2009	DBLP DOI BibTeX RDF	Two step template matching, Genetic algorithms, Correlation coefficient
37	Daniel S. Spiegel, Lisa M. Frye, Linda L. Day	Issues in the instantiation of template classes.	ACM SIGCSE Bull.	2008	DBLP DOI BibTeX RDF	borland model, explicit instantiation, gnu compiler, header file, implementation file, implicit instantiation, template class, C++
37	Biagio Freni, Gian Luca Marcialis, Fabio Roli	Template Selection by Editing Algorithms: A Case Study in Face Recognition.	SSPR/SPR	2008	DBLP DOI BibTeX RDF	template selection, face recognition, biometrics, Nearest neighbour
37	Shuyi Zheng, Ruihua Song, Ji-Rong Wen, Di Wu	Joint optimization of wrapper generation and template detection.	KDD	2007	DBLP DOI BibTeX RDF	information extraction, wrapper, template detection
37	David Marimon, Touradj Ebrahimi	Efficient Rotation-Discriminative Template Matching.	CIARP	2007	DBLP DOI BibTeX RDF	matching, histogram, template, rotation, gradient
37	K. Murugesan, P. Elango	CNN Based Hole Filler Template Design Using Numerical Integration Techniques.	ICANN (1)	2007	DBLP DOI BibTeX RDF	Hole-filler template, Numerical Integration algorithms, Euler method, Modified-Euler method, RK-method, Cellular neural network
37	Karane Vieira, Altigran Soares da Silva, Nick Pinto, Edleno Silva de Moura, João M. B. Cavalcanti, Juliana Freire	A fast and robust method for web page template detection and removal.	CIKM	2006	DBLP DOI BibTeX RDF	web page noise removal, web template extraction
37	Liang Chen, Shaozhi Ye, Xing Li	Template detection for large scale search engines.	SAC	2006	DBLP DOI BibTeX RDF	clustering, web page segmentation, template detection
37	Zoltán Porkoláb, József Mihalicza, Ádám Sipos	Debugging C++ template metaprograms.	GPCE	2006	DBLP DOI BibTeX RDF	template metaprogramming, C++, debugging
37	Sukhyun Lim, Byeong-Seok Shin	Reliable Space Leaping Using Distance Template.	ISBMDA	2004	DBLP DOI BibTeX RDF	volume ray casting, min-max map, distance template, space leaping
37	Pin Xie, Sheng Uei Guan	A golden-template self-generating method for patterned wafer inspection.	Mach. Vis. Appl.	2000	DBLP DOI BibTeX RDF	Wafer inspection, Golden template, Spectral estimation, PDI, Image-to-image reference method
37	Simon K. Warfield, Michael Kaus, Ferenc A. Jolesz, Ron Kikinis	Adaptive Template Moderated Spatially Varying Statistical Classification.	MICCAI	1998	DBLP DOI BibTeX RDF	template moderated segmentation, nearest neighbour classification, knee cartilage, neonate, tumour, brain, elastic matching
37	Cheol-Hi Lee, Yun-Mo Koo, Yeong-Gil Shin	Template-based rendering of run-length encoded volumes.	PG	1997	DBLP DOI BibTeX RDF	object-order template-based volume rendering method, run-length encoded volumes, volume ray casting, rendering speed, ray-by-ray volume access pattern, ray path length, transparent regions, principal axis direction, object-order volume traversal, image quality, rendering (computer graphics), acceleration technique, interactive manipulation
37	Dongrong Xu, Xuejun Hao, Ravi Bansal, Kerstin J. Plessen, Bradley S. Peterson	Seamless Warping of Diffusion Tensor Fields.	IEEE Trans. Medical Imaging	2008	DBLP DOI BibTeX RDF
37	Karthik Nandakumar, Anil K. Jain 0001, Sharath Pankanti	Fingerprint-Based Fuzzy Vault: Implementation and Performance.	IEEE Trans. Inf. Forensics Secur.	2007	DBLP DOI BibTeX RDF
37	Thomas Kwok, Thao Nguyen	An Automatic Electronic Contract Document Signing System in a Secure Environment.	CEC	2005	DBLP DOI BibTeX RDF
37	I-Ane Huang, Jan-Ming Ho, Hung-Yu Kao, Shian-Hua Lin	Extracting Citation Metadata from Online Publication Lists Using BLAST.	PAKDD	2004	DBLP DOI BibTeX RDF
36	Arathi Arakala, J. Shane Culpepper, Jason Jeffers, Andrew Turpin, Serdar Boztas, Kathy J. Horadam, Allison M. McKendrick	Entropy of the Retina Template.	ICB	2009	DBLP DOI BibTeX RDF
36	Ajita Rattani, Gian Luca Marcialis, Fabio Roli	An Experimental Analysis of the Relationship between Biometric Template Update and the Doddington's Zoo: A Case Study in Face Verification.	ICIAP	2009	DBLP DOI BibTeX RDF
36	John W. Carls, Richard A. Raines, Michael R. Grimaila, Steven K. Rogers	Biometric enhancements: Template aging error score analysis.	FG	2008	DBLP DOI BibTeX RDF
36	Yong-Huai Huang, Kuo-Liang Chung	Texture- and Multiple-Template-Based Algorithm for Lossless Compression of Error-Diffused Images.	IEEE Trans. Image Process.	2007	DBLP DOI BibTeX RDF
36	Yoshinori Suzuki, Choong Seng Boon, Thiow Keng Tan	Inter Frame Coding with Template Matching Averaging.	ICIP (3)	2007	DBLP DOI BibTeX RDF
36	Feng Tang, Hai Tao	Fast Multi-scale Template Matching Using Binary Features.	WACV	2007	DBLP DOI BibTeX RDF
36	Wang Guogang, Zhang Zhijia, Wang Ying	Research on SVD-Based Template-Updating Strategy.	IEEE ICCI	2006	DBLP DOI BibTeX RDF
36	Zhen Jia, Arjuna P. Balasuriya, Subhash Challa	Target tracking with Bayesian fusion based template matching.	ICIP (2)	2005	DBLP DOI BibTeX RDF
36	Choonwoo Ryu, Youngchan Han, Hakil Kim	Super-template Generation Using Successive Bayesian Estimation for Fingerprint Enrollment.	AVBPA	2005	DBLP DOI BibTeX RDF
36	Lina Mi, Fumiaki Takeda	Research on Individual Recognition System with Writing Pressure Based on Customized Neuro-template with Gaussian Function.	KES (2)	2005	DBLP DOI BibTeX RDF
36	Jiun-Hung Chen	An Application of Robust Template Matching to User Location on Wireless Infrastructure.	ICPR (3)	2004	DBLP DOI BibTeX RDF
36	Shawn Phillips, Akshay Sharma, Scott Hauck	Automating the Layout of Reconfigurable Subsystems via Template Reduction.	FPL	2004	DBLP DOI BibTeX RDF
36	Jun-Wei Hsieh, W. Eric L. Grimson	Spatial template extraction for image retrieval by region matching.	IEEE Trans. Image Process.	2003	DBLP DOI BibTeX RDF
36	Nobuaki Takahashi, Tsuyoshi Otake, Mamoru Tanaka	The template optimization of discrete time CNN for image compression and reconstruction.	ISCAS (1)	2002	DBLP DOI BibTeX RDF
36	Yu Huang 0007, Thomas S. Huang, Heinrich Niemann	Two-Handed Gesture Tracking Incorporating Template Warping with Static Segmentation.	FGR	2002	DBLP DOI BibTeX RDF	segmentation, tracking, gesture
36	Pieter Op de Beeck, Francisco Barat, Murali Jayapala, Rudy Lauwereins	CRISP: A Template for Reconfigurable Instruction Set Processors.	FPL	2001	DBLP DOI BibTeX RDF
36	Koichi Tanaka, Mutsuo Sano, Shuichi Ohara, Masashi Okudaira	A Parametric Template Method and Its Application to Robust Matching.	CVPR	2000	DBLP DOI BibTeX RDF
36	Fereidoon Sadri, Jeffrey D. Ullman	The Interaction between Functional Dependencies and Template Dependencies.	SIGMOD Conference	1980	DBLP DOI BibTeX RDF
35	Mark A. Cameron, Kerry L. Taylor, David J. Abel	The Internet Marketplace Template: An Architecture Template for Inter-enterprise Information Systems.	CoopIS	2001	DBLP DOI BibTeX RDF