880 research outputs found
Pricing Patents through Citations
This paper provides formal treatment to the idea of patenting as a form of market stealing between R&D firms. It extends the creative destruction literature by allowing innovations to build off each other forming a network of ideas. Patent citations keep track of this network. The theory maps the distribution of productivities in the development of new ideas onto the distribution of patent values through patent citations. If productivities are drawn from a Pareto-Levy distribution then the distribution of patent values also falls within this class. The theory is then applied to data on US patent citations. Model-based valuations support the assumption of Pareto-distributed productivities. As an added feature, model-based valuations outperform citation counts (the traditional measure) as a proxy for patent valuesPatents, Innovation, R&D, Networks
La realidad a prueba de lo virtual / Reality challenged by the virtual world
Entrados en la era de la revolución digital, la humanidad –lo mismo que las formas estructurales en que se han sostenido los intercambios sociales a lo largo de la historia– experimentan el día de hoy una trasformación que bien podríamos llamar “heterogénesis”, tan radical que amenaza con subvertir los supuestos del orden más natural: el cuerpo, la identidad sexual, la certeza de morir o enfermar e incluso el mismo sentido de realidad, los cuales empiezan a difuminar sus fundamentos en lo psíquico. El hombre se ha arrancado la piel de su especie para encontrar en lo virtual, en el reflejo de las pantallas, su nueva condición –imaginaria– de “superhombre” libre de las ataduras de lo real, pero embebido por el placer alucinógeno de una realidad de fantasía en la que está cautivo. ¿Qué consecuencias trae pues el impacto desmedido de las realidades de síntesis en el psiquismo humano?Nowadays, when we have entered into the age of the digital revolution, humanity –same as the structural
forms in which social exchanges have been maintained all through history– head toward a radical transformation that we could name “heterogenesis”, which menaces in subverting the basic mental conditions of all natural order: body, sexual identity, death, and sickness certainty, even reality itself as never after is beginning to dissolve it’s basis in the psychical dimension. Humanity has pull out its own species skin in order to find in the virtual, in the screens bright, its new identity –imaginary– as “superman”, free from the ties of what is real but absorbed by the hallucinogenic pleasure of a fake reality from which we are prisoners. Which are the consequences that a disproportionate impact with synthetic realities brings to the mental health of humans
Estudio experimental de una barrera acústica compuesta de cenizas volantes
Although fly ash is commonly used as an additive to cement, large amounts of this material are disposed in landfills. To mitigate, it would be interesting to develop new products in which fly ash can be easily used and required in large quantities. In this work, fly ash is added to manufacture eco-friendly materials with acceptable acoustic and non-acoustic properties and a low cost. We built a barrier composed of fly ash (60 wt.%), type II Portland cement (25 wt.%), vermiculite (14.5 wt.%) and polypropylene fibers (0.5 wt.%). The barrier complied with the mechanical requirements of European standards. The sound absorption coefficient and the airborne sound insulation were determined in a reverberation room, and the barrier was classified as A2 and B3. No leaching problems were observed.Aunque las cenizas volantes se usan comúnmente como una adición en la fabricación del cemento, grandes cantidades se siguen depositando en vertedero. Para mitigar este problema, es interesante desarrollar nuevos productos en los que las cenizas volantes se puedan usar fácilmente en grandes cantidades. En este trabajo, se emplean cenizas volantes para fabricar materiales con una alta absorción acústica, con propiedades mecánicas aceptables y un bajo coste. Se ha construido una barrera compuesta de cenizas volantes (60% en peso), cemento Portland tipo II (25% en peso), vermiculita (14.5% en peso) y fibras de polipropileno (0.5% en peso). La barrera cumplió con los requisitos mecánicos establecidos de las normas europeas. El coeficiente de absorción acústica y el aislamiento acústico en el aire se han determinado en una sala de reverberación, y la barrera se clasificó como A2 y B3. No se han observado problemas de lixiviación
Distraction by deviant sounds: disgusting and neutral words capture attention to the same extent
Several studies have argued that words evoking negative emotions, such as disgust, grab attention more than neutral words, and leave traces in memory that are more persistent. However, these conclusions are typically based on tasks requiring participants to process the semantic content of these words in a voluntarily manner. We sought to compare the involuntary attention grabbing power of disgusting and neutral words using them as rare and unexpected auditory distractors in a cross-modal oddball task, and then probing the participants’ memory for these stimuli in a surprise recognition task. Frequentist and Bayesian analyses converged to show that, compared to a standard tone, disgusting and neutral auditory words produced significant but equivalent levels of distraction in a visual categorization task, that they elicited comparable levels of memory discriminability in the incidental recognition task, and that the participants’ individual sensitivity to disgust did not influence the results. Our results suggest that distraction by unexpected words is not modulated by their emotional valence, at least when these words are task-irrelevant and are temporally and perceptually decoupled from the target stimuliThis work was supported by Research Grants PSI2014-54261-P, PSI2015-63525-P, and PSI2015-65116-P from the Spanish Ministry of Science, Innovation and Universities (MICINN), the Spanish State Agency for Research (AEI) and the European Regional Development Fund (FEDER), as well as Grants 2017PFR-URV-B2-32 from the Universitat Rovira i Virgili, and GRC 2015/006 from (Xunta de Galicia). Fabrice B. R. Parmentier’s contract at the University of the Balearic Islands is co-financed by the MICINN’s program for the incentivization and permanent incorporation of doctors (2016 call, Ref IEDI-2016-00742). Fabrice B. R. Parmentier is also an Adjunct Senior Lecturer at the University of Western AustraliaS
Supersymmetric partners of the trigonometric Poschl-Teller potentials
The first and second-order supersymmetry transformations are used to generate
Hamiltonians with known spectra departing from the trigonometric Poschl-Teller
potentials. The several possibilities of manipulating the initial spectrum are
fully explored, and it is shown how to modify one or two levels, or even to
leave the spectrum unaffected. The behavior of the new potentials at the
boundaries of the domain is studied.Comment: 20 pages, 4 figure
Diversity of behavior after collisions of Sn and Si nanoparticles found using a new Density-Functional Tight-Binding model
We present a new approach to studying nanoparticle collisions using Density
Functional based Tight Binding (DFTB). A novel DFTB parameterisation has been
developed to study the collision process of Sn and Si nanoparticles (NPs) using
Molecular Dynamics (MD). While bulk structures were used as training sets, we
show that our model is able to accurately reproduce the cohesive energy of the
nanoparticles using Density Functional Theory (DFT) as a reference. A
surprising variety of phenomena are revealed for the Si/Sn nanoparticle
collisions, depending on the size and velocity of the collision: from
core-shell structure formation to bounce-off phenomena.Comment: 13 pages, 15 figure
Synthesis of a new polypyridinic highly conjugated ligand with electron-acceptor properties
A new acceptor polypyridinic ligand functionalized with a quinone fragment is reported. The ligand, dipyrido[3,2-a:2′,3′-c]-benzo[3,4]-phenazine-11,16-quinone, Nqphen, was synthesized by condensation of 1,10-phenanthroline-5,6-dione and 2,3-diamino-1,4-naphthoquinone. The syntheses of two rhenium complexes with this ligand are also reported
Reciclado de residuos cerámicos en materiales absorbentes acústicos
The scope of this investigation is to develop a material mainly composed (80% w/w) of ceramic wastes that can be applied in the manufacture of road traffic noise reducing devices. The characterization of the product has been carried out attending to its acoustic, physical and mechanical properties, by measuring the sound absorption coefficient at normal incidence, the open void ratio, density and compressive strength. Since the sound absorbing behavior of a porous material is related to the size of the pores and the thickness of the specimen tested, the influence of the particle grain size of the ceramic waste and the thickness of the samples tested on the properties of the final product has been analyzed. The results obtained have been compared to a porous concrete made of crushed granite aggregate as a reference commercial material traditionally used in similar applications. Compositions with coarse particles showed greater sound absorption properties than compositions made with finer particles, besides presenting better sound absorption behavior than the reference porous concrete. Therefore, a ceramic waste-based porous concrete can be potentially recycled in the highway noise barriers field.El objetivo de este trabajo es desarrollar un material absorbente acústico compuesto fundamentalmente por residuos cerámicos (80% p) que se pueda utilizar en la fabricación de dispositivos reductores de ruido de carretera. La caracterización del producto se ha llevado a cabo atendiendo a sus propiedades acústicas, físicas y mecánicas, determinando el coeficiente de absorción acústica a incidencia normal, porosidad abierta, densidad y resistencia a compresión. La absorción acústica de un material poroso está fuertemente determinada por el tamaño de poro y por la longitud dela probeta sometida a ensayo. De este modo, se ha analizado la influencia del tamaño de partícula del residuo cerámico y del espesor de las muestras estudiadas en las propiedades del producto final. Los resultados obtenidos se han comparado con los obtenidos para un hormigón poroso elaborado con árido grueso, que se ha tomado como producto de referencia tradicionalmente empleado en este tipo de aplicaciones. Las composiciones elaboradas con el residuo de mayor tamaño de partícula han mostrado mayor absorción acústica, incluso mayor que las del hormigón poroso comercial. Por tanto, un hormigón poroso elaborado con residuos cerámicos puede ser potencialmente empleado como material en la fabricación de barreras acústicas de carretera
Synthesis and characterization of polypiridine-based rhenium(I) complexes with pyrazino[2,3-f][1,10]phenanthroline
A series of tricarbonyl rhenium(I) complexes of the type fac-[Re 1(CO)3(Ppl)(L)]0/+, where ppl is pyrazino[2,3-f][1,10]phenanthroline, and where L is Cl-, TIO -, 4-(tert-butyl)pyridine (tBu-py), 4-methoxypyridine (MeO-py), 4,4′-bipyridyl (bpy), or 10-(picolin-4-yl)phenothiazine (pptz), were synthesized and fully characterized. In all complexes, an increment in the electron-acceptor properties of ppl compared to the free ligand was observed. This effect was more significant for pyridine-type ligands, especially for pptz, compared to Cl- or TfO-. The properties of fac-[Re(CO)3(ppl)(pptz)]PF6 were compared with those of the analogous compound fac-[Re(CO)3(dppz)(pptz)]PF6, where dppz is dipyrido(3,2-a: 2′,3′-c)phenazine, the goal being to generate long-lived excited charge-transfer (CT) states. In this respect, fac-[Re(CO)3(ppl)(pptz)]PF6 seems to be a promising candidate
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