Search results for " Engines"
showing 10 items of 26 documents
P-FCM: a proximity-based fuzzy clustering for user-centered web applications
2003
Abstract In last years, the Internet and the web have been evolved in an astonishing way. Standard web search services play an important role as useful tools for the Internet community even though they suffer from a certain difficulty. The web continues its growth, making the reliability of Internet-based information and retrieval systems more complex. Nevertheless there has been a substantial analysis of the gap between the expected information and the returned information, the work of web search engine is still very hard. There are different problems concerning web searching activity, one among these falls in the query phase. Each engine provide an interface which the user is forced to le…
Aprenentatge basat en projectes: aproximació a l'ensenyament de sistemes de potència de gas i vapor
2014
L’objectiu d’aquest treball és presentar l’experiència i els resultats derivats de l’aplicació del mètode d’aprenentatge basat en projectes (PBL) de l’assignatura de Termotècnia de la titulació d’Enginyeria Química de la Universitat del País Basc/Euskal Herriko Unibertsitatea. Després d’un anàlisi crític dels resultats acadèmics dels alumnes que aprenen motors tèrmics, s’observa que l’estratègia d’ensenyament-aprenentatge tradicional, basat en classes magistrals + classes d’aplicació en una llista d’exercicis (totalment acotats i amb una solució única), està fallant. Davant d’aquesta situació, es planteja un enfoc constructivista centrat en l’alumne perquè ell mateix construeixi el seu apre…
Magnetic field-induced alignment of molecular rotor-shaped cyclophanes
2010
Molecular pinwheels consisting of dipolar substituted cyclophanes in solution can function as free microscopic rotors in the presence of a homogeneous static magnetic field B and a circularly polarized electric field E rotating on a plane containing B. Owing to the high magnetic anisotropy of [26](1,2,3,4,5,6)cyclophane and [36](1,2,3,4,5,6)cyclophane biased by strong ring currents, ∼1 in 105 molecules are expected to align with the C6 symmetry axis perpendicular to a magnetic field of 21 T. The magnetic-field-controlled alignment of rotor-shaped cyclophanes is insignificantly affected by nonpolar solvents, for example, toluene.
IMPLICACIONES DEL USO DE BUSCADORES EN EL COMPORTAMIENTO DE COMPRA ONLINE / IMPLICATIONS OF THE SEARCH ENGINES USE IN THE ONLINE SHOPPING BEHAVIOUR
2009
El objetivo del presente trabajo es analizar los factores que influyen en el uso de buscadores y su incidencia en el comportamiento de compra en Internet. El análisis de resultados obtenidos a partir de una muestra representativa de 485 compradores por Internet españoles, pone de manifiesto que los consumidores que consideran la comodidad, reducciones de precio y amplitud de surtido como motivaciones relevantes para realizar compras online presentan una mayor predisposición al uso de buscadores en la realización de sus compras virtuales. La experiencia como internauta y como comprador en Internet son factores que influyen negativamente en el uso de buscadores para la realización de compras …
«Lex Google»: Copyright Law and Internet Providers, Future Enemies or Allies?
2013
The German Federal Parliament is discussing the approval of the so-called “Lex Google” which will amend the German Copyright Act and provide for a number of improvements to the management of copyrighted content by Internet Service Providers. This paper focuses on the advantages and disadvantages linked to the diffusion of copyrighted content over the Internet and suggests that the Lex Google would benefit from taking better into account E-Commerce rules and ECJ case-law on Internet Service Providers.
Effectively and efficiently supporting crowd-enabled databases via NoSQL paradigms
2013
In this paper we provide an overview of the Hints From the Crowd (HFC) project, whose main goal is to build a NoSQL database system for large collections of product reviews; the database is queried by expressing a natural language sentence; the result is a list of products ranked based on the relevance of reviews w.r.t. the natural language sentence. The best ranked products in the result list can be seen as the best hints for the user based on crowd opinions (the reviews). The HFC prototype has been developed as a web application, independent of the particular application domain of the collected product reviews. Queries are performed by evaluating a text-based ranking metric for sets of re…
Search for Subsolar-Mass Ultracompact Binaries in Advanced LIGO's First Observing Run
2018
We present the first Advanced LIGO and Advanced Virgo search for ultracompact binary systems with component masses between 0.2 $M_\odot$ - 1.0 $M_\odot$ using data taken between September 12, 2015 and January 19, 2016. We find no viable gravitational wave candidates. Our null result constrains the coalescence rate of monochromatic (delta function) distributions of non-spinning (0.2 $M_\odot$, 0.2 $M_\odot$) ultracompact binaries to be less than $1.0 \times 10^6 \text{Gpc}^{-3} \text{yr}^{-1}$ and the coalescence rate of a similar distribution of (1.0 $M_\odot$, 1.0 $M_\odot$) ultracompact binaries to be less than $1.9 \times 10^4 \text{Gpc}^{-3} \text{yr}^{-1}$ (at 90 percent confidence). N…
A Study on the Use of Combustion Phase Indicators for MBT Spark Timing on a Bi-Fuel Engine
2007
The performance of a spark ignition engine strongly depends on the phase of the combustion process with respect to piston motion, and hence on the spark advance; this fundamental parameter is actually controlled in open-loop by means of maps drawn up on the test bench and stored in the Electronic Control Unit (ECU). Bi-fuel engines (e.g. running either on gasoline or on natural gas) require a double mapping process in order to obtain a spark timing map for each of the fuels. This map based open-loop control however does not assure to run the engine always with the best spark timing, which can be influenced by many factors, like ambient condition of pressure, temperature and humidity, fuel p…
An NTC zone compliant knock onset prediction model for spark ignition engines
2015
Abstract Pollutant emissions reduction and energy saving policies increased the production of Spark Ignition (SI) engines operated with gaseous fuels. Natural Gas (NG) and Liquefied Petroleum Gas (LPG), thanks to their low cost and low environmental impact represent the best alternative. Bi-fuel engines, which may run either with gasoline or with gas (NG or LPG), widely spread in many countries thanks to their versatility, high efficiency and low pollutant emissions: gas fueled vehicles, as example, are allowed to run in many limited traffic zones. In the last years, supercharged SI engines fueled with either gasoline or gaseous fuel, spread in the market. Thermodynamic simulations, widely …
Supercharging the Double-Fueled Spark Ignition Engine: Performance and Efficiency
2017
Internal combustion engine development focuses mainly on two aspects: fuel economy improvement and pollutant emissions reduction. As a consequence, light duty spark ignition (SI) engines have become smaller, supercharged, and equipped with direct injection and advanced valve train control systems. The use of alternative fuels, such as natural gas (NG) and liquefied petroleum gas (LPG), thanks to their lower cost and environmental impact, widely spread in the automotive market, above all in bifuel vehicles, whose spark ignited engines may run either with gasoline or with gaseous fuel. The authors in previous works experimentally tested the strong engine efficiency increment and pollutant emi…