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Institution

Aalto University

EducationEspoo, Finland
About: Aalto University is a education organization based out in Espoo, Finland. It is known for research contribution in the topics: Population & Carbon nanotube. The organization has 9969 authors who have published 32648 publications receiving 829626 citations. The organization is also known as: TKK & Aalto-korkeakoulu.


Papers
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Journal ArticleDOI
TL;DR: Reconfigurable intelligent surfaces (RISs) can be realized in different ways, which include (i) large arrays of inexpensive antennas that are usually spaced half of the wavelength apart; and (ii) metamaterial-based planar or conformal large surfaces whose scattering elements have sizes and inter-distances much smaller than the wavelength.
Abstract: Reconfigurable intelligent surfaces (RISs) are an emerging transmission technology for application to wireless communications. RISs can be realized in different ways, which include (i) large arrays of inexpensive antennas that are usually spaced half of the wavelength apart; and (ii) metamaterial-based planar or conformal large surfaces whose scattering elements have sizes and inter-distances much smaller than the wavelength. Compared with other transmission technologies, e.g., phased arrays, multi-antenna transmitters, and relays, RISs require the largest number of scattering elements, but each of them needs to be backed by the fewest and least costly components. Also, no power amplifiers are usually needed. For these reasons, RISs constitute a promising software-defined architecture that can be realized at reduced cost, size, weight, and power (C-SWaP design), and are regarded as an enabling technology for realizing the emerging concept of smart radio environments (SREs). In this paper, we (i) introduce the emerging research field of RIS-empowered SREs; (ii) overview the most suitable applications of RISs in wireless networks; (iii) present an electromagnetic-based communication-theoretic framework for analyzing and optimizing metamaterial-based RISs; (iv) provide a comprehensive overview of the current state of research; and (v) discuss the most important research issues to tackle. Owing to the interdisciplinary essence of RIS-empowered SREs, finally, we put forth the need of reconciling and reuniting C. E. Shannon’s mathematical theory of communication with G. Green’s and J. C. Maxwell’s mathematical theories of electromagnetism for appropriately modeling, analyzing, optimizing, and deploying future wireless networks empowered by RISs.

1,158 citations

Journal ArticleDOI
TL;DR: In this paper, the state of the art of optical modulators based on 2D materials, including graphene, transition metal dichalcogenides and black phosphorus, is reviewed.
Abstract: Light modulation is an essential operation in photonics and optoelectronics. With existing and emerging technologies increasingly demanding compact, efficient, fast and broadband optical modulators, high-performance light modulation solutions are becoming indispensable. The recent realization that 2D layered materials could modulate light with superior performance has prompted intense research and significant advances, paving the way for realistic applications. In this Review, we cover the state of the art of optical modulators based on 2D materials, including graphene, transition metal dichalcogenides and black phosphorus. We discuss recent advances employing hybrid structures, such as 2D heterostructures, plasmonic structures, and silicon and fibre integrated structures. We also take a look at the future perspectives and discuss the potential of yet relatively unexplored mechanisms, such as magneto-optic and acousto-optic modulation.

1,158 citations

Proceedings ArticleDOI
03 Oct 2012
TL;DR: A new definition for gamification is proposed, which emphases the experiential nature of games and gamification, instead of the systemic understanding, and ties this definition to theory from service marketing because majority of gamification implementations aim towards goals of marketing, which brings to the discussion the notion of how customer / user is always ultimately the creator of value.
Abstract: During recent years "gamification" has gained significant attention among practitioners and game scholars. However, the current understanding of gamification has been solely based on the act of adding systemic game elements into services. In this paper, we propose a new definition for gamification, which emphases the experiential nature of games and gamification, instead of the systemic understanding. Furthermore, we tie this definition to theory from service marketing because majority of gamification implementations aim towards goals of marketing, which brings to the discussion the notion of how customer / user is always ultimately the creator of value. Since now, the main venue for academic discussion on gamification has mainly been the HCI community. We find it relevant both for industry practitioners as well as for academics to study how gamification can fit in the body of knowledge of existing service literature because the goals and the means of gamification and marketing have a significant overlap.

1,148 citations

Journal ArticleDOI
Kurt Lejaeghere1, Gustav Bihlmayer2, Torbjörn Björkman3, Torbjörn Björkman4, Peter Blaha5, Stefan Blügel2, Volker Blum6, Damien Caliste7, Ivano E. Castelli8, Stewart J. Clark9, Andrea Dal Corso10, Stefano de Gironcoli10, Thierry Deutsch7, J. K. Dewhurst11, Igor Di Marco12, Claudia Draxl13, Claudia Draxl14, Marcin Dulak15, Olle Eriksson12, José A. Flores-Livas11, Kevin F. Garrity16, Luigi Genovese7, Paolo Giannozzi17, Matteo Giantomassi18, Stefan Goedecker19, Xavier Gonze18, Oscar Grånäs12, Oscar Grånäs20, E. K. U. Gross11, Andris Gulans14, Andris Gulans13, Francois Gygi21, D. R. Hamann22, P. J. Hasnip23, Natalie Holzwarth24, Diana Iusan12, Dominik B. Jochym25, F. Jollet, Daniel M. Jones26, Georg Kresse27, Klaus Koepernik28, Klaus Koepernik29, Emine Kucukbenli10, Emine Kucukbenli8, Yaroslav Kvashnin12, Inka L. M. Locht30, Inka L. M. Locht12, Sven Lubeck14, Martijn Marsman27, Nicola Marzari8, Ulrike Nitzsche28, Lars Nordström12, Taisuke Ozaki31, Lorenzo Paulatto32, Chris J. Pickard33, Ward Poelmans1, Matt Probert23, Keith Refson34, Keith Refson25, Manuel Richter29, Manuel Richter28, Gian-Marco Rignanese18, Santanu Saha19, Matthias Scheffler13, Matthias Scheffler35, Martin Schlipf21, Karlheinz Schwarz5, Sangeeta Sharma11, Francesca Tavazza16, Patrik Thunström5, Alexandre Tkatchenko13, Alexandre Tkatchenko36, Marc Torrent, David Vanderbilt22, Michiel van Setten18, Veronique Van Speybroeck1, John M. Wills37, Jonathan R. Yates26, Guo-Xu Zhang38, Stefaan Cottenier1 
25 Mar 2016-Science
TL;DR: A procedure to assess the precision of DFT methods was devised and used to demonstrate reproducibility among many of the most widely used DFT codes, demonstrating that the precisionof DFT implementations can be determined, even in the absence of one absolute reference code.
Abstract: The widespread popularity of density functional theory has given rise to an extensive range of dedicated codes for predicting molecular and crystalline properties. However, each code implements the formalism in a different way, raising questions about the reproducibility of such predictions. We report the results of a community-wide effort that compared 15 solid-state codes, using 40 different potentials or basis set types, to assess the quality of the Perdew-Burke-Ernzerhof equations of state for 71 elemental crystals. We conclude that predictions from recent codes and pseudopotentials agree very well, with pairwise differences that are comparable to those between different high-precision experiments. Older methods, however, have less precise agreement. Our benchmark provides a framework for users and developers to document the precision of new applications and methodological improvements.

1,141 citations

Journal ArticleDOI
TL;DR: In this article, the authors provide an extensive review and an updated research agenda for the field, classified into nine main themes: understanding transitions; power, agency and politics; governing transitions; civil society, culture and social movements; businesses and industries; transitions in practice and everyday life; geography of transitions; ethical aspects; and methodologies.
Abstract: Research on sustainability transitions has expanded rapidly in the last ten years, diversified in terms of topics and geographical applications, and deepened with respect to theories and methods. This article provides an extensive review and an updated research agenda for the field, classified into nine main themes: understanding transitions; power, agency and politics; governing transitions; civil society, culture and social movements; businesses and industries; transitions in practice and everyday life; geography of transitions; ethical aspects; and methodologies. The review shows that the scope of sustainability transitions research has broadened and connections to established disciplines have grown stronger. At the same time, we see that the grand challenges related to sustainability remain unsolved, calling for continued efforts and an acceleration of ongoing transitions. Transition studies can play a key role in this regard by creating new perspectives, approaches and understanding and helping to move society in the direction of sustainability.

1,099 citations


Authors

Showing all 10135 results

NameH-indexPapersCitations
John B. Goodenough1511064113741
Ashok Kumar1515654164086
Anne Lähteenmäki11648581977
Kalyanmoy Deb112713122802
Riitta Hari11149143873
Robin I. M. Dunbar11158647498
Andreas Richter11076948262
Mika Sillanpää96101944260
Muhammad Farooq92134137533
Ivo Babuška9037641465
Merja Penttilä8730322351
Andries Meijerink8742629335
T. Poutanen8612033158
Sajal K. Das85112429785
Kalle Lyytinen8442627708
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Performance
Metrics
No. of papers from the Institution in previous years
YearPapers
2023101
2022342
20212,842
20203,030
20192,749
20182,719