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  • Author or Editor: M. Martin x
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We study the pairs (S,L)of positive random variables which arise in the a .ne de- compositions T (law) =S +L 2 T of the stable

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Abstract  

Three hundred ancient Turkish potsherds were analyzed by instrumental neutron activation analysis, and the resulting data analyzed by several techniques of multivariate statistical analysis, some only recently developed. The programs AGCLUS, MASLOC, and SIMCA were sequentially employed to characterize and group the samples by type of pottery and by site of excavation or collection. Comparison of the statistical analyses by each method provided archaeological insight into the site/type relationships of the samples and ultimately evidence relevant to commercial relations between the ancient communities and to specialization of pottery production over time. The techniques used for statistical analysis were found to be of significant potential utility in the future analysis of other archaeometric data sets.

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Abstract

Given that in terms of technology novel inventions are crucial factors for companies; this article contributes to the identification of inventions of high novelty in patent data. As companies are confronted with an information overflow, and having patents reviewed by experts is a time-consuming task, we introduce a new approach to the identification of inventions of high novelty: a specific form of semantic patent analysis. Subsequent to the introduction of the concept of novelty in patents, the classical method of semantic patent analysis will be adapted to support novelty measurement. By means of a case study from the automotive industry, we corroborate that semantic patent analysis is able to outperform available methods for the identification of inventions of high novelty. Accordingly, semantic patent information possesses the potential to enhance technology monitoring while reducing both costs and uncertainty in the identification of inventions of high novelty.

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Abstract

For certain tasks in patent management it makes sense to apply a quantitative measure of textual similarity between patents and/or parts thereof: be it the analysis of freedom to operate, the analysis of technology convergence, or the mapping of patents for strategic purposes. In this paper we intend to outline the process of measuring textual patent similarity on the basis of elements referred to as ‘combined concepts’. We are going to use this process in various operations leading to design decisions, and shall also provide guidance regarding these decisions. By way of two applications from patent management, namely the prioritization of patents and the analysis of convergence between two technological fields, we mean to demonstrate the crucial importance of design decisions in terms of patent analysis results.

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A comparison of an HPGe planar detector and an HPGe coaxial detector, both with short length-to-diameter ratios, provides empirical evidence for the advantage of the coaxial configuration in measurements of actinide radionuclides. The principal advantage is related to the lower capacitance of a coaxial detector relative to that of a planar detector, both with large active frontal areas. In addition, the higher interaction probability (efficiency) of Ge versus Si underscores the advantages of Ge for measurements of samples with -ray energies from 5 to 200 keV (235U and241Pu). The advantages are also dependent on the presence of other higher-energy -rays collimated versus diffuse-sample geometry, and (for bioassay applications) the intervening scattering mediums of bone and tissue.

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Polymer crystallization

Isothermal and non-isothermal spherulite growth parameters from optical microscopy and differential scanning calorimetry

Journal of Thermal Analysis and Calorimetry
Authors: J. Martins, J. Cruz-Pinto and M. Oliveira

Abstract  

Differential scanning calorimetry (dual furnace, null-balance, DSC) and optical microscopy (OM) have been used to study the isothermal crystallization kinetics of poly(oxymethylene)-POM. The non-isothermal crystallization of the same material has also been studied by optical microscopy. A very controversial problem is whether the isothermal kinetic parameters may be applied to describe the non-isothermal crystallization. The results show that the kinetic spherulite growth parameters obtained by non-isothermal optical microscopy are, within the experimental errors involved, the same as those obtained by isothermal optical microscopy or isothermal DSC. The importance of this finding is highlighted.

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Thermally Stimulated Current (TSC) spectroscopy and Differential Scanning calorimetry (DSC) have been applied to the characterization of the microstructure of Poly (Ether Ether Ketone)/PEEK. the dielectric relaxation spectra show two modes, dependent upon crystallinity: –  * for the mode stuated in the vicinity of the glass transition temperature, two components have been distinguished and attributed to the molecular mobility in the ‘true amorphous phase’ and in the ‘rigid amorphous region’. –  * below 0°C, two sub-modes appear, situated around-110°C and-75°C, due to the two different crystal entities, beads and laths.

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Abstract  

Calorimetric measurements were made of the heat of immersion in water of cassiterite that was either untreated or treated with 60% HNO3. The heats of immersion of cassiterite and fluorite were also calculated theoretically from the surface Gibbs energy components, and compared with the heat of immersion measured for cassiterite and that taken from the literature for fluorite. The results of the measurements and calculation revealed that the heat of immersion depends on the degree of hydration of the surface of cassiterite and fluorite. It was also found that it is possible to predict the heats of immersion in water of cassiterite and fluorite from the Lifshitz-van der Waals and acid-base components of the surface Gibbs energy.

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