3,178 research outputs found

    Інноваційні чинники макроекономічної динаміки

    Get PDF
    Проаналізовано взаємозв’язок економічних циклів та інновацій. Запропоновано концептуальну схему впливу інновацій на економічне зростання. Обґрунтовано напрями активізації інноваційного чинника задля виходу національних господарств на траєкторію економічного зростання.Проведен анализ взаимосвязи экономических циклов и инноваций. Предложена концептуальная схема влияния инноваций на экономический рост. Обоснованы направления активизации инновационного фактора с целью выхода национальных хозяйств на траекторию экономического роста.The interconnections between economic cycles and innovation are analyzed. Conceptual framework for the influence of innovation on economic growth is proposed. Areas of enhanced innovation factor and output of national economies on the path of economic growth are grounded

    Alien Registration- Morrill, Germaine J. (Limerick, York County)

    Get PDF
    https://digitalmaine.com/alien_docs/3237/thumbnail.jp

    Extinction and dust/gas ratio in LMC molecular clouds

    Get PDF
    Aims. The goal of this paper is to measure the dust content and distribution in the Large Magellanic Cloud (LMC) by comparing extinction maps produced in the near-infrared wavelengths and the spatial distribution of the neutral and molecular gas, as traced by Hi and CO observations. Methods. In order to derive an extinction map of the LMC, we have developed a new method to measure the color excess of dark clouds, using the 2MASS all-sky survey. Classical methods to measure the color excess (including the NICE method) tend to underestimate the true color excess if the clouds are significantly contaminated by unreddened foreground stars, as is the case in the LMC. We propose a new method that uses the color of the X percentile reddest stars and which is robust against such contamination. Using this method, it is possible to infer the positions of dark clouds with respect to the star distribution by comparing the observed color excess as a function of the percentile used and that predicted by a model. Results. On the basis of the resulting extinction map, we perform a correlation analysis for a set of dark molecular clouds. Assuming similar infrared absorption properties for the dust in the neutral and molecular phases, we derive the absorption-to-column density ratio AV/NH and the CO-to-H2 conversion factor X_(CO). We show that AV/NH increases from the outskirts of the LMC towards the 30 Dor star-forming region. This can be explained either by a systematic increase of the dust abundance, or by the presence of an additional gas component not traced by Hi or CO, but strongly correlated to the Hi distribution. If dust abundance is allowed to vary, the derived X_(CO) factors for the selected regions are several times lower than those derived from a virial analysis of the CO data. This could indicate that molecular clouds in the LMC are not gravitationally bound, or that they are bounded by substantial external pressure. However, the X_(CO) values derived from absorption can be reconciled with the virial results assuming a constant value for the dust abundance and the existence of an additional, unseen gas component. These results are in agreement with those derived for the LMC from diffuse far-infrared emission

    Economic Geology Models 5. Specialty, Critical, Battery, Magnet and Photovoltaic Materials: Market Facts, Projections and Implications for Exploration and Development

    Get PDF
    Many exploration companies are now focusing on specialty materials that are associated with so-called ‘green technology’. These include ‘battery materials’, ‘magnet materials’ and ‘photovoltaic materials’, and many such commodities are also broadly labelled as ‘critical materials’ because they are seen as vital for industrial development, societal needs or national security. The definitions used for such materials are not always consistent among jurisdictions or across industry, and this paper attempts to clarify the criteria and address some common misconceptions. The distinction between major minerals (e.g. base metals) and ‘specialty materials’ (i.e. those mined or produced in much smaller amounts) is particularly important.   The markets for many specialty materials are growing faster than those for traditional ferrous, precious and base metals and they are often portrayed as excellent long-term investment opportunities. However, the small market bases for specialty materials and considerable uncertainty around growth projections (especially related to material substitutions and rapid technological change) need to be taken into consideration for objective assessment of the development potential of any proposed project, establishment of new supply chains by major corporations, and responsible decision-making (mineral policy) by government. In the short-term, projects aimed at specialty materials (materials with a small market base) cannot benefit from economy of scale, and their development hinges on commercially proven metallurgical processes, unless they are supported by governments or end-users.   Several specialty metals (e.g. germanium, indium, cadmium, and cobalt) are commonly obtained as by-product of base metal extraction. In such cases, systematic testing of base metal ores for their specialty metal content may justify the addition of relevant recovery circuits to existing smelters. If positive results are obtained, the need for targeting new sources of such specialty metals as primary exploration targets may be reduced or eliminated.   Where market conditions permit and concerns about the future availability of materials seem reliable, grass-roots exploration for specialty materials is warranted, and pre-competitive government involvement may be justified to promote such development efforts.De nombreuses sociétés d'exploration se concentrent désormais sur les matériaux spécialisés associés à ce que l'on appelle la « technologie verte ». Ceux-ci incluent les « matériaux pour batterie », les « matériaux magnétiques » et les « matériaux photovoltaïques », et de nombreux produits de ce type sont aussi largement étiquetés comme « matériaux critiques » car ils sont considérés comme vitaux pour le développement industriel, les besoins sociétaux ou la sécurité nationale. Les définitions utilisées pour ces matériaux ne sont pas toujours cohérentes entre les juridictions ou dans l'industrie, et ce document tente de clarifier les critères et de répondre à certaines idées fausses courantes. La distinction entre les principaux minéraux (par exemple les métaux de base) et les « matériaux spécialisés » (c'est-à-dire ceux extraits ou produits en quantités beaucoup plus faibles) est particulièrement importante.  Les marchés de nombreux matériaux spécialisés croissent plus rapidement que ceux des métaux ferreux, précieux et de base traditionnels et ils sont souvent présentés comme d'excellentes opportunités d'investissement à long terme. Cependant, le marché restreint des matériaux spécialisés et l'incertitude considérable entourant les projections de croissance (en particulier liées aux substitutions de matériaux et aux changements technologiques rapides) doivent être pris en considération pour une évaluation objective du potentiel de développement de tout projet proposé, l'établissement de nouvelles chaînes d'approvisionnement par les grandes entreprises et une prise de décisions responsable par le gouvernement (politique minière). À court terme, les projets visant des matériaux spécialisés (matériaux ayant un marché restreint) ne peuvent pas bénéficier d'économies d'échelle et leur développement repose sur des procédés métallurgiques commercialement éprouvés, à moins qu'ils ne soient soutenus par les gouvernements ou les utilisateurs finaux.  Plusieurs métaux spécialisés (par exemple le germanium, l'indium, le cadmium et le cobalt) sont couramment obtenus comme sous-produits de l'extraction des métaux de base. Dans de tels cas, l'analyse systématique des minerais de métaux de base pour leur teneur en métaux spécialisés peut justifier l'ajout de circuits de récupération adéquats aux fonderies existantes. Si des résultats positifs sont obtenus, la nécessité de cibler de nouvelles sources de ces métaux spécialisés en tant que cibles d'exploration primaires peut être réduite ou éliminée.  Lorsque les conditions du marché le permettent et que les craintes quant à la disponibilité future des matériaux semblent fiables, l'exploration primaire de matériaux spécialisés est justifiée, et la participation préconcurrentielle du gouvernement peut être justifiée pour promouvoir de tels efforts de développement.

    Measure of the path integral in lattice gauge theory

    Full text link
    We show how to construct the measure of the path integral in lattice gauge theory. This measure contains a factor beyond the standard Haar measure. Such factor becomes relevant for the calculation of a single transition amplitude (in contrast to the calculation of ratios of amplitudes). Single amplitudes are required for computation of the partition function and the free energy. For U(1) lattice gauge theory, we present a numerical simulation of the transition amplitude comparing the path integral with the evolution in terms of the Hamiltonian, showing good agreement.Comment: 5 pages, 2 figure

    Detection and characterization of a 500 μm dust emissivity excess in the Galactic plane using Herschel/Hi-GAL observations

    Get PDF
    Context. Past and recent observations have revealed unexpected variations in the far-infrared – millimeter (FIR-mm) dust emissivity in the interstellar medium. In the Herschel spectral range, those are often referred to as a 500 μm emission excess. Several dust emission models have been developed to interpret astrophysical data in the FIR-mm domain. However, these are commonly unable to fully reconcile theoretical predictions with observations. In contrast, the recently revised two level system (TLS) model, based on the disordered internal structure of amorphous dust grains, seems to provide a promising way of interpreting existing data. Aims. The newly available Herschel infrared GALactic (Hi-GAL) data, which covers most of the inner Milky Way, offers a unique opportunity to investigate possible variations in the dust emission properties both with wavelength and environment. The goal of our analysis is to constrain the internal structure of the largest dust grains on Galactic scales, in the framework of the TLS model. Methods. By combining the IRIS (Improved Reprocessing of the IRAS Survey) 100 μm with the Hi-GAL 160, 250, 350, and 500 μm data, we model the dust emission spectra in each pixel of the Hi-GAL maps, using both the TLS model and, for comparison, a single modified black-body fit. The effect of temperature mixing along the line of sight is investigated to test the robustness of our results. Results. We find a slight decrease in the dust temperature with distance from the Galactic center, confirming previous results. We also report the detection of a significant 500 μm emissivity excess in the peripheral regions of the plane (35° < |l| < 70°) of about 13–15% of the emissivity, which can reach up to 20% in some HII regions. We present the spatial distributions of the best-fit values for the two main parameters of the TLS model, i.e. the charge correlation length, lc, used to characterize the disordered charge distribution (DCD) part of the model, and the amplitude A of the TLS processes with respect to the DCD effect. These distributions illustrate the variations in the dust properties with environment, in particular the plausible existence of an overall gradient with distance to the Galactic center. A comparison with previous findings in the solar neighborhood shows that the local value of the excess is less than expected from the Galactic gradient observed here

    The molecular complex associated with the Galactic HII region Sh2-90: a possible site of triggered star formation

    Full text link
    We investigate the star formation activity in the molecular complex associated with the Galactic HII region Sh2-90, using radio-continuum maps obtained at 1280 MHz and 610 MHz, Herschel Hi-GAL observations at 70 -- 500 microns, and deep near-infrared observation at JHK bands, along with Spitzer observations. Sh2-90 presents a bubble morphology in the mid-IR (size ~ 0.9 pc x 1.6 pc). Radio observations suggest it is an evolved HII region with an electron density ~ 144 cm^-3, emission measure ~ 6.7 x 10^4 cm^-6 pc and a ionized mass ~ 55 Msun. From Hi-GAL observations it is found that the HII region is part of an elongated extended molecular cloud (size ~ 5.6 pc x 9.7 pc, H_2 column density >= 3 x 10^21 cm^-2 and dust temperature 18 -- 27 K) of total mass >= 1 x 10^4 Msun. We identify the ionizing cluster of Sh2-90, the main exciting star being an O8--O9 V star. Five cold dust clumps (mass ~ 8 -- 95 Msun), four mid-IR blobs around B stars, and a compact HII region are found at the edge of the bubble.The velocity information derived from CO (J=3-2) data cubes suggests that most of them are associated with the Sh2-90 region. 129 YSOs are identified (Class I, Class II, and near-IR excess sources). The majority of the YSOs are low mass (<= 3 Msun) sources and they are distributed mostly in the regions of high column density. Four candidate Class 0/I MYSOs have been found; they will possibly evolve to stars of mass >= 15 Msun. We suggest multi-generation star formation is present in the complex. From the evidences of interaction, the time scales involved and the evolutionary status of stellar/protostellar sources, we argue that the star formation at the immediate border/edges of Sh2-90 might have been triggered by the expanding HII region. However, several young sources in this complex are probably formed by some other processes.Comment: 22 pages, 22 figures, accepted for publication in Astronomy and Astrophysic
    corecore