298 resultados para Lyman
Resumo:
Pinewood Estate is a significant resource in the history of the theory and practice of landscape architecture. The purpose of this thesis is to provide a landscape plan to restore the Pinewood Estate to its historic integrity in order to retain and reflect its past. In order to determine the criteria used to establish how and to what period the estate should be restored to, the Secretary of the Interior's Guidelines for the Treatment of Cultural Landscapes was followed. This process involved documenting the existing conditions of the estate. Site inventory and analysis and onsite interviews were conducted. Natural and cultural resources were evaluated. As a case study, McKee Botanical Garden was analyzed and evaluated. The comparison of this case study served as a guideline to determine the best practice for the historical preservation of the estate. Despite the changes in the landscape at Pinewood Estate over the past seventy years, the garden today still retains William Lyman Phillips design criteria. For the garden to continue to keep its historic fabric, rehabilitation was selected to allow for improvements that make possible efficient contemporary use of the estate.
Resumo:
MC is grateful to Karen Lupo and Brian Codding for the invitation to participate in the symposium honouring Jim O’Connell at the 2015 annual meeting of the Society for American Archaeology in San Francisco, and for the invitation to contribute to this special issue of the Journal of Anthropological Archaeology. We thank Conrad Brimacombe, Kate Britton, Keith Dobney, Mana Dembo, Marina Elliott, Ian Gilligan, Brian Hayden, Trenton Holliday, Vance Hutchinson, Steve Kuhn, Dana Lepofsky, Lee Lyman, Luseadra McKerracher, Kim Plomp, Bernard Wood, and an anonymous reviewer for their comments on earlier versions of this paper. Ian Gilligan’s comments in particular resulted in major changes to the interpretation of the results. MC is supported by the Social Sciences and Humanities Research Council of Canada, the Canada Research Chairs Program, the Canada Foundation for Innovation, the British Columbia Knowledge Development Fund, and Simon Fraser University. LT work on the study reported here was supported by the Social Sciences and Humanities Research Council of Canada (award no. 755-2011-0406). We are grateful to all these funding bodies. Last but not least, MC would like to express his gratitude to Jim O’Connell for his friendship and guidance over nearly 20 years. Thanks Jim. You’re the dog’s bollocks.
Resumo:
The relationship between population and government in the City of Buenos Aires is analyzed, focusing on the tensions generated by the arrival of new individuals, a local elite with great interests in commerce and in charge of community affairs, and Spanish functionaries that progressively adopted the ideals of the Bourbon Dynasty, despite also being implicated in local logics. It interests us to observe the governors’ perspectives with respect to everyday developments in the city, their preoccupations and interests, and how they would vary the mechanisms to which they resorted in order to organize daily life, in the period defined between 1740 and 1776.
Resumo:
We present results based on observations of SN 2015H which belongs to the small group of objects similar to SN 2002cx, otherwise known as type Iax supernovae. The availability of deep pre-explosion imaging allowed us to place tight constraints on the explosion epoch. Our observational campaign began approximately one day post-explosion, and extended over a period of about 150 days post maximum light, making it one of the best observed objects of this class to date. We find a peak magnitude of Mr = -17.27± 0.07, and a (Δm15)r = 0.69 ± 0.04. Comparing our observations to synthetic spectra generated from simulations of deflagrations of Chandrasekhar mass carbon-oxygen white dwarfs, we find reasonable agreement with models of weak deflagrations that result in the ejection of ∼0.2 M⊙ of material containing ∼0.07 M⊙ of 56Ni. The model light curve however, evolves more rapidly than observations, suggesting that a higher ejecta mass is to be favoured. Nevertheless, empirical modelling of the pseudo-bolometric light curve suggests that ≲ 0.6 M⊙ of material was ejected, implying that the white dwarf is not completely disrupted, and that a bound remnant is a likely outcome.
Resumo:
We present an analysis of an X-class flare that occurred on 11 June 2014 in active region NOAA 12087 using a newly developed high cadence Image
Selector operated by Astronomical Institute in Ondrejov, Czech Republic. This instrument provides spectra in the 350 - 440 nm wavelength range, which
covers the higher order Balmer lines as well as the Balmer jump at 364 nm. However, no detectable increase in these emissions were detected during
the flare, and support observations from SDO/EVE MEGS-B also show that the Lyman line series and recombination continuum were also suppressed,
particularly when compared to an M-class flare that occurred an hour earlier, and two other X-class flares on the preceding day. The X-class flare under
investigation also showed strong white light emission in SDO/HMI data, as well as an extremely hard electron spectrum ( 3.6), and
-ray emission,
from RHESSI data. This unique combination of datasets allows us to conclude that the white light emission from this flare corresponds to a black body
heated by high-energy electrons (and/or ions), as opposed to optical chromospheric emission from hydrogen.
Resumo:
Thesis (Ph.D.)--University of Washington, 2016-08
Resumo:
Simplifying the Einstein field equation by assuming the cosmological principle yields a set of differential equations which governs the dynamics of the universe as described in the cosmological standard model. The cosmological principle assumes the space appears the same everywhere and in every direction and moreover, the principle has earned its position as a fundamental assumption in cosmology by being compatible with the observations of the 20th century. It was not until the current century when observations in cosmological scales showed significant deviation from isotropy and homogeneity implying the violation of the principle. Among these observations are the inconsistency between local and non-local Hubble parameter evaluations, baryon acoustic features of the Lyman-α forest and the anomalies of the cosmic microwave background radiation. As a consequence, cosmological models beyond the cosmological principle have been studied vastly; after all, the principle is a hypothesis and as such should frequently be tested as any other assumption in physics. In this thesis, the effects of inhomogeneity and anisotropy, arising as a consequence of discarding the cosmological principle, is investigated. The geometry and matter content of the universe becomes more cumbersome and the resulting effects on the Einstein field equation is introduced. The cosmological standard model and its issues, both fundamental and observational are presented. Particular interest is given to the local Hubble parameter, supernova explosion, baryon acoustic oscillation, and cosmic microwave background observations and the cosmological constant problems. Explored and proposed resolutions emerging by violating the cosmological principle are reviewed. This thesis is concluded by a summary and outlook of the included research papers.
Resumo:
Ɣ-ray bursts (GRBs) are the Universe's most luminous transient events. Since the discovery of GRBs was announced in 1973, efforts have been ongoing to obtain data over a broader range of the electromagnetic spectrum at the earliest possible times following the initial detection. The discovery of the theorized ``afterglow'' emission in radio through X-ray bands in the late 1990s confirmed the cosmological nature of these events. At present, GRB afterglows are among the best probes of the early Universe (z ≳ 9). In addition to informing theories about GRBs themselves, observations of afterglows probe the circum-burst medium (CBM), properties of the host galaxies and the progress of cosmic reionization. To explore the early-time variability of afterglows, I have developed a generalized analysis framework which models near-infrared (NIR), optical, ultra-violet (UV) and X-ray light curves without assuming an underlying model. These fits are then used to construct the spectral energy distribution (SED) of afterglows at arbitrary times within the observed window. Physical models are then used to explore the evolution of the SED parameter space with time. I demonstrate that this framework produces evidence of the photodestruction of dust in the CBM of GRB 120119A, similar to the findings from a previous study of this afterglow. The framework is additionally applied to the afterglows of GRB 140419A and GRB 080607. In these cases the evolution of the SEDs appears consistent with the standard fireball model. Having introduced the scientific motivations for early-time observations, I introduce the Rapid Infrared Imager-Spectrometer (RIMAS). Once commissioned on the 4.3 meter Discovery Channel Telescope (DCT), RIMAS will be used to study the afterglows of GRBs through photometric and spectroscopic observations beginning within minutes of the initial burst. The instrument will operate in the NIR, from 0.97 μm to 2.37 μm, permitting the detection of very high redshift (z ≳ 7) afterglows which are attenuated at shorter wavelengths by Lyman-ɑ absorption in the intergalactic medium (IGM). A majority of my graduate work has been spent designing and aligning RIMAS's cryogenic (~80 K) optical systems. Design efforts have included an original camera used to image the field surrounding spectroscopic slits, tolerancing and optimizing all of the instrument's optics, thermal modeling of optomechanical systems, and modeling the diffraction efficiencies for some of the dispersive elements. To align the cryogenic optics, I developed a procedure that was successfully used for a majority of the instrument's sub-assemblies. My work on this cryogenic instrument has necessitated experimental and computational projects to design and validate designs of several subsystems. Two of these projects describe simple and effective measurements of optomechanical components in vacuum and at cryogenic temperatures using an 8-bit CCD camera. Models of heat transfer via electrical harnesses used to provide current to motors located within the cryostat are also presented.
Resumo:
El presente estudio de caso busca examinar la incidencia de las medidas migratorias de control fronterizo implementadas por el Frontex y el gobierno Italiano en las condiciones mínimas de supervivencia de los migrantes irregulares, económicos y solicitantes de asilo en la Isla de Lampedusa, en el periodo 2011-2015. De esta manera, se identifican las medidas migratorias de control fronterizo implementadas por Frontex y el gobierno Italiano. Se examina la situación de la seguridad humana en la crisis migratoria de la Isla, y se analiza la relación entre las medidas migratorias de control fronterizo y las condiciones mínimas de supervivencia de los migrantes. El resultado de la investigación permite plasmar, las consecuencias negativas que han tenido las medidas migratorias en cuanto a las condiciones mínimas de supervivencia, lo que ha desembocado en una crisis humanitaria.