989 research outputs found
The Game Theory in Quantum Computers: A Review
Game theory has been studied extensively in recent centuries as a set of formal mathematical strategies for optimal decision making. This discipline improved its efficiency with the arrival, in the 20th century, of digital computer science. However, the computational limitations related to exponential time type problems in digital processors, triggered the search for more efficient alternatives. One of these choices is quantum computing. Certainly, quantum processors seem to be able to solve some of these complex problems, at least in theory. For this reason, in recent times, many research works have emerged related to the field of quantum game theory. In this paper we review the main studies about the subject, including operational requirements and implementation details. In addition, we describe various quantum games, their design strategy, and the used supporting tools. We also present the still open debate linked to the interpretation of the transformations of classical algorithms in fundamental game theory to their quantum version, with special attention to the Nash equilibrium
On-Surface Hydrogen-Induced Covalent Coupling of Polycyclic Aromatic Hydrocarbons via a Superhydrogenated Intermediate
The activation and subsequent covalent coupling of polycyclic aromatic
hydrocarbons (PAHs) are of great interest in fields like chemistry, energy,
biology, or health, among others. However, this is not a trivial process. So
far, it is based on the use of catalysts that drive and increase the efficiency
of the reaction. Here, we report on an unprecedented method in which the
dehydrogenation and covalent coupling is thermally activated in the presence of
atomic hydrogen and a surface. This mechanism, which requires of the
superhydrogenation of the PAHs, has been characterized by high-resolution
scanning tunnelling microscopy (STM) and rationalized by density functional
theory (DFT) calculations. This work opens a door toward the formation of
covalent, PAH-based, macromolecular nanostructures on low-reactive surfaces,
thus facilitating its applicability.Comment: This manuscript version is made available under the CC-BY-NC-ND 4.0
licens
Noise Sources, Effects and Countermeasures in Narrowband Power-Line Communications Networks: A Practical Approach
The integration of Distributed Generation, Electric Vehicles, and storage without compromising the quality of the power delivery requires the deployment of a communications overlay that allows monitoring and controlling low voltage networks in almost real time. Power Line Communications are gaining momentum for this purpose since they present a great trade-off between economic and technical features. However, the power lines also represent a harsh communications medium which presents different problems such as noise, which is indeed affected by Distributed Generation, Electric Vehicles, and storage. This paper provides a comprehensive overview of the types of noise that affects Narrowband Power Line Communications, including normative noises, noises coming from common electronic devices measured in actual operational power distribution networks, and noises coming from photovoltaic inverters and electric vehicle charging spots measured in a controlled environment. The paper also reviews several techniques to mitigate the effects of noise, paying special attention to passive filtering, as for being one of the most widely used solution to avoid this kind of problems in the field. In addition, the paper presents a set of tests carried out to evaluate the impact of some representative noises on Narrowband Power Line Communications network performance, as well as the effectiveness of different passive filter configurations to mitigate such an impact. In addition, the considered sources of noise can also bring value to further improve PLC communications in the new scenarios of the Smart Grid as an input to theoretical models or simulations.This work has been partly funded by the Spanish Ministry of Economy and Competitiveness through the National Program for Research Aimed at the Challenges of Society under the project OSIRIS (RTC-2014-1556-3) and through the network of excellence REDYD2050 (ENE2015-70032-REDT)
Noise Sources, Effects and Countermeasures in Narrowband Power-Line Communications Networks: A Practical Approach
The integration of Distributed Generation, Electric Vehicles, and storage without compromising the quality of the power delivery requires the deployment of a communications overlay that allows monitoring and controlling low voltage networks in almost real time. Power Line Communications are gaining momentum for this purpose since they present a great trade-off between economic and technical features. However, the power lines also represent a harsh communications medium which presents different problems such as noise, which is indeed affected by Distributed Generation, Electric Vehicles, and storage. This paper provides a comprehensive overview of the types of noise that affects Narrowband Power Line Communications, including normative noises, noises coming from common electronic devices measured in actual operational power distribution networks, and noises coming from photovoltaic inverters and electric vehicle charging spots measured in a controlled environment. The paper also reviews several techniques to mitigate the effects of noise, paying special attention to passive filtering, as for being one of the most widely used solution to avoid this kind of problems in the field. In addition, the paper presents a set of tests carried out to evaluate the impact of some representative noises on Narrowband Power Line Communications network performance, as well as the effectiveness of different passive filter configurations to mitigate such an impact. In addition, the considered sources of noise can also bring value to further improve PLC communications in the new scenarios of the Smart Grid as an input to theoretical models or simulations.This work has been partly funded by the Spanish Ministry of Economy and Competitiveness through the National Program for Research Aimed at the Challenges of Society under the project OSIRIS (RTC-2014-1556-3) and through the network of excellence REDYD2050 (ENE2015-70032-REDT)
Contacto e emoções no ensino de desportos sóciomotores de colaboração-oposição a futuros docentes de educação física
[Resumen]: Partiendo de la conceptualización de los problemas afectivos derivados del contacto (PADC) estudiamos su influencia en el aprendizaje de Rugby, Balonmano y Voleibol. El trabajo, desarrollado en el contexto universitario (n=16), se aborda dentro del paradigma cualitativo, mediante el análisis de contenido y con el apoyo de estrategias cuantitativas, siguiendo los Métodos Mixtos. El estudio prospectivo de los datos permitió describir la realidad a estudiar y el refinamiento de la metodología, centrada en el método de análisis de diarios con entrevista sobre los diarios, con el apoyo de herramientas informáticas de análisis cualitativo (Nvivo). Los resultados muestran la existencia de PADC y su influencia negativa en el aprendizaje de tareas motrices de los deportes estudiados. Las emociones que suscitan la aparición de estos problemas están fundamentalmente relacionadas con el miedo, aunque también con la ansiedad y/o la vergüenza. Además, se describen cuáles son los tipos de contactos que generan esos problemas. Igualmente, se concretan 29 factores que podrían ser valorados para disminuir la aparición de los PADC en procesos de enseñanza-aprendizaje de tareas motrices que impliquen contacto. La importancia de cada uno de estos factores varía en función del tipo de contacto que requiera la tarea motriz.[Abstract]: From the conceptualization of emotional problems related to contact (EPRC), we study its influence in the learning of Rugby, Handball and Volleyball. This research, developed at the university sphere (n=16), is framed within qualitative framework through the analysis of content assisted with quantitative strategies (Mixed Methods). The prospective study of the data allowed the description of the reality in study and the refinement in methodology. So, the method focused on the analysis of diaries with interviews about them with the support of computer tools of qualitative analysis (NVivo). The results show the existence of EPRC and its negative influence in the learning of motor tasks of the aforementioned sports. The emotions that facilitate the appearance of these problems are fundamentally related to fear, but also to anxiety or shame. In addition, the types of contacts that generate these problems are described. Furthermore, there were specified 29 factors that could be considerated to decrease the appearance of EPRCs in contact motor tasks teaching-learning processes. The importance of each of these factors varies depending on the type of contact that the motor task requires.[Resumo]: Partindo da conceituação de problemas afetivos derivados do contacto (PADC), estudamos sua influência na aprendizagem de Rugby, Handebol e Voleibol. O trabalho, desenvolvido no contexto universitário (n=16), é abordado dentro do paradigma qualitativo, através do método de análise de conteúdo e com o apoio de estratégias quantitativas, seguindo os Métodos Mistos. O estudo prospetivo dos dados permitiu descrever a realidade a ser estudada e o aprimoramento da metodologia, centrada no método de análise de diários com entrevista sobre os diários, com o apoio duma ferramenta computacional de análise qualitativa (Nvivo). Os resultados mostram a existência do PADC e sua influência negativa na aprendizagem de tarefas motoras dos desportos observados. As emoções produtoras desses problemas estão fundamentalmente relacionadas ao medo, mas também à ansiedade ou vergonha. Além disso, são descritos os tipos de contactos que geram esses problemas. Da mesma forma, foram especificados 29 fatores que poderiam ser avaliados para diminuir a aparência dos PADCs nos processos de ensino-aprendizagem de tarefas motoras que envolvem contacto. A importância de cada um desses fatores varia de acordo com o tipo de contacto que a tarefa motora exig
Organizaciones virtuales y redes neuronales. Algunas similitudes.
Aunque existen numerosos trabajos que identifican sus principales características y modo de funcionamiento, el estudio de las organizaciones virtuales adolece de una carencia de modelos matemáticos que reflejen su comportamiento de un modo cuantitativo. En este sentido, a lo largo del presente trabajo se tratará de poner de manifiesto las similitudes existentes entre el funcionamiento de las organizaciones virtuales y el de las redes neuronales (SOM, SelfOrganizing Maps). El objetivo es sentar las bases para proponer este tipo de técnica estadística como herramienta para la formulación de modelos sobre organizaciones virtuales. Se plantearán una serie de argumentos de plausibilidad, dejando a investigaciones posteriores la verificación rigurosa de esta propuesta.ORGANIZACION VIRTUAL, REDES SOM, MAPAS DE KOHONEN
Reliability of IBM’s Public Quantum Computers
One of the challenges of the current ecosystem of quantum computers (QC) is the stabilization of the coherence associated with the entanglement of the states of their inner qubits. In this empirical study, we monitor the reliability of IBM’s public-access QCs network on a daily basis. Each of these state-of-the-art machines has a totally different qubit association, and this entails that for a given (same) input program, they may output a different set of probabilities for the assembly of results (including both the right and the wrong ones). Although we focus on the computing structure provided by the “Big Blue” company, our survey can be easily transferred to other currently available quantum mainframes. In more detail, we probe these quantum processors with an ad hoc designed computationally demanding quaternary search algorithm. As stated, this quantum program is executed every 24 hours (for nearly 100 days) and its goal is to put to the limit the operational capacity of this novel and genuine type of equipment. Next, we perform a comparative analysis of the obtained results according to the singularities of each computer and over the total number of executions. In addition, we subsequently apply (for 50 days) an improvement filtering to perform noise mitigation on the results obtained proposed by IBM. The Yorktown 5-qubit computer reaches noise filtering of up to 33% in one day, that is, a 90% confidence level is reached in the expected results. From our continuous and long-term tests, we derive that room still exists regarding the improvement of quantum calculators in order to guarantee enough confidence in the returned outcomes
Agent-based simulation with NetLogo to evaluate ambient intelligence scenarios
In This Paper An Agent-Based Simulation Is Developed In Order To Evaluate An Ambient Intelligence Scenario Based On Agents. Many Ami Applications Are Implemented Through Agents But They Are Not Compared With Any Other Existing Alternative In Order To Evaluate The Relative Benefits Of Using Them. The Proposed Simulation Environment Analyses Such Benefits Using Two Evaluation Criteria: First, Measuring Agent Satisfaction Of Different Types Of Desires Along The Execution. Second, Measuring Time Savings Obtained Through A Correct Use Of Context Information. In This Paper An Existing Agent Architecture, An Ontology And A 12-Steps Protocol To Provide Ami Services In Airports, Is Evaluated Using The Netlogo Simulation Environment. In Our Netlogo Model We Are Considering Scalability Issues Of This Application Domain But Using Fipa And Bdi Extensions To Be Coherent With Our Previous Works And Our Previous Jade Implementation Of Them. The Netlogo Model Simulates An Airport With Agent '
Passengers'
Passing Through Several Zones Located In A Specific Order In A Map: Passport Controls, Check-In Counters Of Airline Companies, Boarding Gates, Different Types Of Shopping. Although The Initial Data In Each Simulation Is Generated Randomly, And The Model Is Just An Approximation Of Real-World Airports, The Definition Of This Case Of Use Of Ami Through Netlogo Agents Opens An Interesting Way To Evaluate The Benefits Of Using Ami, Which Is A Significant Contribution To The Final Development Of Ami Systems.This work was partially funded by CNPq PVE Project 314017/2013-5, FAPERJ APQ1 Project 211.500/2015 and by Projects MINECO TEC2012-37832-C02-01, CICYT TEC2011-28626-C02-0
El impacto del uso efectivo de las TIC sobre la eficiencia técnica de las empresas españolas
Los numerosos estudios llevados acabo acerca del efecto de las Tecnologíasde la Información y lasComunicaciones (TIC) sobre la productividadde las firmas han puestode manifiesto que no es suficienteinvertir en TIC, sino que una seriede inversiones adicionales, prácticasorganizativas específicas, etc, sonnecesarias. En este trabajo se muestracómo el efecto del simple uso delas TIC sobre el rendimiento de lasfirmas es irrelevante, mientras quesu uso para la comunicación conclientes y proveedores eleva significativamentesu desempeño. La magnitudutilizada para caracterizar estedesempeño es la eficiencia técnica enel proceso de conversión de inputs enoutputs. Esta eficiencia técnica se hacalculado utilizando un modelo deData Envelopment Analysis, metodologíaestándar en estudios sobreproductividad, pero que hasta lafecha apenas ha sido utilizada paraanalizar el impacto de las TIC sobreel rendimiento empresarial.Tecnologías de la Información, EficienciaTécnica, Data Envelopment Analysis, Cadena de Aprovisionamiento.
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