31 resultados para depth perception
Filtro por publicador
- ABACUS. Repositorio de Producción Científica - Universidad Europea (1)
- Abertay Research Collections - Abertay University’s repository (1)
- Aberystwyth University Repository - Reino Unido (1)
- AMS Tesi di Dottorato - Alm@DL - Università di Bologna (1)
- Aquatic Commons (22)
- ArchiMeD - Elektronische Publikationen der Universität Mainz - Alemanha (2)
- Archivo Digital para la Docencia y la Investigación - Repositorio Institucional de la Universidad del País Vasco (3)
- Aston University Research Archive (8)
- Avian Conservation and Ecology - Eletronic Cientific Hournal - Écologie et conservation des oiseaux: (1)
- B-Digital - Universidade Fernando Pessoa - Portugal (1)
- Biblioteca Digital da Produção Intelectual da Universidade de São Paulo (2)
- Biblioteca Digital de Teses e Dissertações Eletrônicas da UERJ (2)
- BORIS: Bern Open Repository and Information System - Berna - Suiça (3)
- Boston University Digital Common (26)
- Brock University, Canada (30)
- CaltechTHESIS (6)
- Cambridge University Engineering Department Publications Database (63)
- CentAUR: Central Archive University of Reading - UK (67)
- Chinese Academy of Sciences Institutional Repositories Grid Portal (68)
- Cochin University of Science & Technology (CUSAT), India (8)
- CORA - Cork Open Research Archive - University College Cork - Ireland (3)
- Deakin Research Online - Australia (9)
- DI-fusion - The institutional repository of Université Libre de Bruxelles (1)
- Digital Commons at Florida International University (2)
- DigitalCommons@The Texas Medical Center (3)
- Duke University (7)
- eResearch Archive - Queensland Department of Agriculture; Fisheries and Forestry (5)
- Gallica, Bibliotheque Numerique - Bibliothèque nationale de France (French National Library) (BnF), France (12)
- Glasgow Theses Service (1)
- Greenwich Academic Literature Archive - UK (4)
- Helda - Digital Repository of University of Helsinki (12)
- Indian Institute of Science - Bangalore - Índia (31)
- Instituto Politécnico do Porto, Portugal (1)
- Massachusetts Institute of Technology (14)
- Ministerio de Cultura, Spain (14)
- National Center for Biotechnology Information - NCBI (1)
- Plymouth Marine Science Electronic Archive (PlyMSEA) (21)
- Portal de Revistas Científicas Complutenses - Espanha (4)
- QUB Research Portal - Research Directory and Institutional Repository for Queen's University Belfast (124)
- Queensland University of Technology - ePrints Archive (175)
- ReCiL - Repositório Científico Lusófona - Grupo Lusófona, Portugal (1)
- Repositório Institucional da Universidade de Aveiro - Portugal (6)
- Repositório Institucional UNESP - Universidade Estadual Paulista "Julio de Mesquita Filho" (3)
- Research Open Access Repository of the University of East London. (2)
- RUN (Repositório da Universidade Nova de Lisboa) - FCT (Faculdade de Cienecias e Technologia), Universidade Nova de Lisboa (UNL), Portugal (7)
- SAPIENTIA - Universidade do Algarve - Portugal (7)
- Savoirs UdeS : plateforme de diffusion de la production intellectuelle de l’Université de Sherbrooke - Canada (5)
- School of Medicine, Washington University, United States (35)
- SerWisS - Server für Wissenschaftliche Schriften der Fachhochschule Hannover (1)
- Universidad de Alicante (1)
- Universidad del Rosario, Colombia (8)
- Universidad Politécnica de Madrid (6)
- Universidade de Lisboa - Repositório Aberto (1)
- Universidade Federal do Pará (1)
- Universitat de Girona, Spain (11)
- Universitätsbibliothek Kassel, Universität Kassel, Germany (6)
- Université de Lausanne, Switzerland (5)
- Université de Montréal, Canada (101)
- Université Laval Mémoires et thèses électroniques (1)
- University of Michigan (1)
- University of Queensland eSpace - Australia (1)
- University of Southampton, United Kingdom (5)
- University of Washington (2)
- WestminsterResearch - UK (3)
- Worcester Research and Publications - Worcester Research and Publications - UK (4)
Resumo:
We show here a 2(Omega(root d.log N)) size lower bound for homogeneous depth four arithmetic formulas. That is, we give an explicit family of polynomials of degree d on N variables (with N = d(3) in our case) with 0, 1-coefficients such that for any representation of a polynomial f in this family of the form f = Sigma(i) Pi(j) Q(ij), where the Q(ij)'s are homogeneous polynomials (recall that a polynomial is said to be homogeneous if all its monomials have the same degree), it must hold that Sigma(i,j) (Number of monomials of Q(ij)) >= 2(Omega(root d.log N)). The above mentioned family, which we refer to as the Nisan-Wigderson design-based family of polynomials, is in the complexity class VNP. Our work builds on the recent lower bound results 1], 2], 3], 4], 5] and yields an improved quantitative bound as compared to the quasi-polynomial lower bound of 6] and the N-Omega(log log (N)) lower bound in the independent work of 7].