Effect of uniaxial pressure on the ferroelectric phase transition in Pb5Ge3O11 : Ba crystals

The effect of uniaxial pressure up to 1 kbar applied perpendicular and parallel to c-axis, on the Curie temperature and electric permittivity "c of Ba-doped Pb5Ge3O11 single crystals was investigated. The Curie temperature decreases with uniaxial pressure and the coe±cient °i (°i ´ ±Tc=±Xi) is determined as {7 and {11 K kbar¡1 for the b- and c-axes, respectively. It was found that uniaxial pressure increases the phase transition diffuseness and the tricritical point cannot be achieved for this pyroelectric and ferroelectric single crystal

Forecasting of sports fields construction costs aided by ensembles of neural networks

The paper presents an original approach to construction cost analysis and development of predictive models based on ensembles of artificial neural networks. The research was focused on the application of two alternative approaches of ensemble averaging that allow for combining a number of multilayer perceptron neural networks and developing effective models for cost predictions. The models have been developed for the purpose of forecasting construction costs of sports fields as a specific type of construction objects. The research included simulation and selection of numerous neural networks that became the members of the ensembles. The ensembles included either the networks of different types in terms of their structure and activation functions or the networks of the same type. The research also included practical implementation of the developed models for cost analysis based on a sports field BIM model. This case study examined and confirmed all of the four models’ predictive capabilities and superiority over models based on single networks for the particular problem. Verification including testing and the case study enabled selection of the best ensemble-based model that combined ten networks of different types. The proposed approach is prospective for fast cost analyses and conceptual estimates in construction projects

System for Detecting Vehicle Features from Low Quality Data

The paper presents a system that recognizes the make, colour and type of the vehicle. The classification has been performed using low quality data from real-traffic measurement devices. For detecting vehicles’ specific features three methods have been developed. They employ several image and signal recognition techniques, e.g. Mamdani Fuzzy Inference System for colour recognition or Scale Invariant Features Transform for make identification. The obtained results are very promising, especially because only on-site equipment, not dedicated for such application, has been employed. In case of car type, the proposed system has better performance than commonly used inductive loops. Extensive information about the vehicle can be used in many fields of Intelligent Transport Systems, especially for traffic supervision. 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Religiousness and lifestyles : a sociological study of slovak families

Dans le chapitre « Cohabitation. An informal Lifestyle » (Cohabitation. Un style de vie informel), nous abordons le thème concernant un phénomène social qui est de plus en plus commun, c’est‑à‑dire la vie en cohabitation. Cette forme informelle et alternative de la vie familiale devient de plus en plus commune et de plus en plus souvent choisie, notamment par la jeune génération. Les résultats des études empiriques que l’on a menées ont démontré que selon les personnes sondées les unions de fait (sous forme de cohabitation) ne constituent pas une forme concurrentielle de vie familiale par rapport au mariage. Les personnes sondées trouvaient aussi que les couples vivant sous forme de cohabitation sont capables de créer des conditions favorables au développement de leurs enfants et, par là, à une famille heureuse. Ces personnes étaient également enclines à attribuer les droits d’adoption aux couples vivant sous forme d’unions libres. Dans la conclusion du chapitre « Trust as a Value of Family Life » (Confiance comme valeur de la vie familiale), nous dirigeons notre attention entre autres sur le fait que le modèle pratique de la famille slovaque (dans le Pays de Nitra) est construit sur des relations émotionnellement fortes entre la mère et l’enfant/les enfants. Ce phénomène est déjà remarqué dans la génération des parents et, grâce à la socialisation familiale et l’éducation, il s’inscrit de façon dynamique dans les pratiques familiales de la génération des jeunes. Ce sont avant tout les femmes qui sont les dépositaires de la confiance sociale. Elles sont aussi les gardiennes de liens entre les générations et les confidentes des affaires difficiles. La culture de confiance en famille est édifiée autour de la mère. La confiance a le visage de la femme. Les résultats des études empiriques, présentés dans le chapitre « Religiosity. An Intergenerational Perspective » (Religiosité. Une perspective intergénérationnelle), permettent d’avancer la thèse concernant le fossé entre les générations (angl. generation gap), se manifestant de façon nette dans la transmission de la culture religieuse entre les générations. En plus, on observe clairement les manifestations de la rupture de la culture religieuse entre les générations. La génération des élèves participe décidément plus rarement aux pratiques religieuses, elle déclare que ses affiliations ecclésiastiques sont plus faibles et se caractérise par une sensibilité religieuse qui est moins intensive que celle de la génération de leurs parents. Les similitudes intergénérationnelles concernant les façons déclarées de participer occasionnellement à la vie des Églises (pratiques qui n’ont lieu qu’une fois), ainsi que les attitudes indiquant le retirement individuel de la vie des communautés religieuses constituent une dérogation à ce principe. Les jeunes et les parents expriment leur conviction à propos de la continuité intergénérationnelle de la transmission de la culture religieuse, ce qui est difficile à confirmer à la lumière des résultats des recherches que l’on présente. La façade de religiosité construite et maintenue dans les visions des élèves et de leurs parents voile les fissures et les déficits existant dans le modèle de la culture slovaque – présentés dans nos études – concernant la socialisation religieuse dans la transmission intergénérationnelle d’attitudes et de comportements religieux. Le chapitre « Patterns of Everyday Life Characterizing Christina Families in the Nitra Regions » (Le modèle de la vie quotidienne des familles chrétiennes dans la région de Nitra) constitue une tentative de reproduire les rythmes quotidiens de la vie des familles dans le Pays de Nitra. C’est notamment la problématique concernant les modèles culturels exprimant les aspects choisis du fonctionnement social des structures familiales qui y est particulièrement accentuée. Les familles examinées sont unies par des liens forts, fondés sur la solidarité et la confiance. Dans la majeure partie des cas, c’est le mariage religieusement sanctionné – dont le but est d’élever des enfants – qui est leur quintessence. Les données recueillies démontrent que parmi les familles examinées domine le modèle « d’égal à égal » – les deux parents s’engagent d’une manière égale à assurer la stabilité financière de la famille et s’occupent du ménage et élèvent les enfants. C’est en même temps le modèle qui est considéré comme le meilleur par les personnes sondées. Les études démontrent à la fois que les personnes sondées accentuent plus fortement le rôle des hommes – pères – dans le cadre de la réalisation des fonctions instrumentales, tandis qu’aux femmes – mères – on attribue le plus souvent l’exécution des tâches à caractère expressif. Les données recueillies démontrent un engagement assez considérable des enfants dans la réalisation des tâches résultant de l’existence quotidienne des familles, ce qui favorise la construction du sentiment de communion avec les proches et de la responsabilité pour eux

Justify your alpha

Benjamin et al. proposed changing the conventional “statistical significance” threshold (i.e.,the alpha level) from p ≤ .05 to p ≤ .005 for all novel claims with relatively low prior odds. They provided two arguments for why lowering the significance threshold would “immediately improve the reproducibility of scientific research.” First, a p-value near .05provides weak evidence for the alternative hypothesis. Second, under certain assumptions, an alpha of .05 leads to high false positive report probabilities (FPRP2 ; the probability that a significant finding is a false positive

Justify your alpha

In response to recommendations to redefine statistical significance to p ≤ .005, we propose that researchers should transparently report and justify all choices they make when designing a study, including the alpha level

Pd/Alumina Catalysts for Beneficial Transformation of Harmful Freon R-22

Chlorodifluoromethane (R-22), the most abundant freon in the atmosphere, was subjected to successful hydrodechlorination in the presence of palladium supported on γ-alumina, at a relatively low reaction temperature (180 °C). The combination of catalytic actions of alumina (performing freon dismutation) and Pd nanoparticles (catalyzing C–Cl bond splitting in the presence of hydrogen) results in the transformation of freon into valuable, chlorine-free products: methane and fluoroform, the mixture of which is used in plasma etching of silicon and silicon nitride. Very highly metal dispersed Pt/Al2O3 catalysts, with metal particles of ~1.3 nm in size, are not as effective as Pd/Al2O3, resulting in only partial dechlorination. A long-term dechlorination screening (3–4 days) showed good catalytic stability of Pd/alumina catalysts.Peer Reviewe

Hydrodechlorination of tetrachloromethane over silica-supported palladium-gold alloys

Compared with the monometallic palladium, bimetallic Pd-Au/SiO2 catalysts show much higher activity and better stability in the reaction of hydrodechlorination of tetrachloromethane, also providing higher selectivity to longer than methane hydrocarbon products. Reasonably mixed Pd-Au particles show better catalytic performance during ~60 h operation, whereas the monometallic palladium and very rich in palladium catalysts suffer rapid deactivation. Smaller amounts of carbon- and chlorine-containing deposits found after reaction on Pd-Au catalysts correspond to their superior catalytic behavior