975 resultados para Work clothes.


Relevância:

20.00% 20.00%

Publicador:

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This Q and A provides an overview of copyright law and how it applies in a variety of scenarios relevant to work based learning (WBL) providers.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Presentation to elected officials [and American Fisheries Society] on the wealth of research to be done in the Chesapeake Bay. Citing drop in oyster production from a high of 17,000,000 bushels in 1885 to 2,000,000 bushels in 1925 or one-eighth of its one-time abundance. Citing water studies through the late 1880's-90's. Report of experiments with the Japanese Oyster O. gigas. Also addresses Crab, Callinectes sapidus and classes held. (PDF contains 7 pages)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The effective stress principle has been efficiently applied to saturated soils in the soil mechanics and geotechnical engineering practice; however, its applicability to unsaturated soils is still under debate. The appropriate selection of stress state variables is essential for the construction of constitutive models for unsaturated soils. Owing to the complexity of unsaturated soils, it is difficult to determine the deformation and strength behaviors of unsaturated soils uniquely with the previous single-effective-stress variable theory and two-effective-stress-variable theory in all the situations. In this paper, based on the porous media theory, the specific expression of work is proposed, and the effective stress of unsaturated soils conjugated with the displacement of the soil skeleton is further derived. In the derived work and energy balance equations, the energy dissipation in unsaturated soils is taken into account. According to the derived work and energy balance equations, all of the three generalized stresses and the conjugated strains have effects on the deformation of unsaturated soils. For considering these effects, a principle of generalized effective stress to describe the behaviors of unsaturated soils is proposed. The proposed principle of generalized effective stress may reduce to the previous effective stress theory of single-stress variable or the two-stress variables under certain conditions. This principle provides a helpful reference for the development of constitutive models for unsaturated soils.

Relevância:

20.00% 20.00%

Publicador:

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In the quest to develop viable designs for third-generation optical interferometric gravitational-wave detectors, one strategy is to monitor the relative momentum or speed of the test-mass mirrors, rather than monitoring their relative position. The most straightforward design for a speed-meter interferometer that accomplishes this is described and analyzed in Chapter 2. This design (due to Braginsky, Gorodetsky, Khalili, and Thorne) is analogous to a microwave-cavity speed meter conceived by Braginsky and Khalili. A mathematical mapping between the microwave speed meter and the optical interferometric speed meter is developed and used to show (in accord with the speed being a quantum nondemolition observable) that in principle the interferometric speed meter can beat the gravitational-wave standard quantum limit (SQL) by an arbitrarily large amount, over an arbitrarily wide range of frequencies . However, in practice, to reach or beat the SQL, this specific speed meter requires exorbitantly high input light power. The physical reason for this is explored, along with other issues such as constraints on performance due to optical dissipation.

Chapter 3 proposes a more sophisticated version of a speed meter. This new design requires only a modest input power and appears to be a fully practical candidate for third-generation LIGO. It can beat the SQL (the approximate sensitivity of second-generation LIGO interferometers) over a broad range of frequencies (~ 10 to 100 Hz in practice) by a factor h/hSQL ~ √W^(SQL)_(circ)/Wcirc. Here Wcirc is the light power circulating in the interferometer arms and WSQL ≃ 800 kW is the circulating power required to beat the SQL at 100 Hz (the LIGO-II power). If squeezed vacuum (with a power-squeeze factor e-2R) is injected into the interferometer's output port, the SQL can be beat with a much reduced laser power: h/hSQL ~ √W^(SQL)_(circ)/Wcirce-2R. For realistic parameters (e-2R ≃ 10 and Wcirc ≃ 800 to 2000 kW), the SQL can be beat by a factor ~ 3 to 4 from 10 to 100 Hz. [However, as the power increases in these expressions, the speed meter becomes more narrow band; additional power and re-optimization of some parameters are required to maintain the wide band.] By performing frequency-dependent homodyne detection on the output (with the aid of two kilometer-scale filter cavities), one can markedly improve the interferometer's sensitivity at frequencies above 100 Hz.

Chapters 2 and 3 are part of an ongoing effort to develop a practical variant of an interferometric speed meter and to combine the speed meter concept with other ideas to yield a promising third- generation interferometric gravitational-wave detector that entails low laser power.

Chapter 4 is a contribution to the foundations for analyzing sources of gravitational waves for LIGO. Specifically, it presents an analysis of the tidal work done on a self-gravitating body (e.g., a neutron star or black hole) in an external tidal field (e.g., that of a binary companion). The change in the mass-energy of the body as a result of the tidal work, or "tidal heating," is analyzed using the Landau-Lifshitz pseudotensor and the local asymptotic rest frame of the body. It is shown that the work done on the body is gauge invariant, while the body-tidal-field interaction energy contained within the body's local asymptotic rest frame is gauge dependent. This is analogous to Newtonian theory, where the interaction energy is shown to depend on how one localizes gravitational energy, but the work done on the body is independent of that localization. These conclusions play a role in analyses, by others, of the dynamics and stability of the inspiraling neutron-star binaries whose gravitational waves are likely to be seen and studied by LIGO.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This article introduces a new listing of published scientific contributions from the Freshwater Biological Association (FBA) and its later Research Council associates – the Institute of Freshwater Ecology (1989–2000) and the Centre for Ecology and Hydrology (2000+). The period 1929–2006 is covered. The authors offer also information on specific features of the listing; also an outline of influences that underlay the research, and its scientific scope.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

It is not hard to see how two visions of nature are intertwined in Darwin’s Journal of Researches: one vision, the province of romantic authors depicting the sentiments awakened by certain landscapes, the other, the domain of natural scientists describing the world without reference to the aesthetic qualities of the scenery. Nevertheless, analyses of this double perspective in Darwin’s work are relatively rare. Most scholars focus on Darwin, the scientist, and more or less ignore the aesthetic aspects of his work. Perceiving the gradual transformation of Darwin’s world view, however, depends on analyzing the two different modes in which Darwin approached and perceived the world. While one can, on occasion, find commentaries on the beauty of the natural world in Darwin’s early work, the passage of time produces a modification in the naturalist’s manner of perceiving nature. This does not, however, mean that Darwin ceases to find beauty in nature; on the contrary, the disenchantment, in Max Weber’s words, that Darwin’s theory produces should not be understood in a pejorative, but rather in a literal sense. The theory of evolution, in effect, divests nature of its magical character and begins to explain it in terms of natural selection, according it, in the process a new and more intense attraction. In the present work, the metaphysical implications of this new vision of the world are analyzed through the eyes of its discoverer.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The siltation of an experimental gravel bed, with three grades of sand moving in suspension and as bedload, was examined. The rate of infiltration of sand into the void space of the gravel was determined under differing conditions of discharge, water depth, and velocity (jointly expressed as variation in the Froude Number) and suspended sediment concentration. The downstream reduction in siltation from the point source was also examined.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A new listing of published scientific contributions from the Freshwater Biological Association (FBA) and its later Research Council associates – the Institute of Freshwater Ecology (1989–2000) and the Centre for Ecology and Hydrology (2000+) is provided. The period 1929–2006 is covered. The compilation extends an earlier list assembled by in 1979.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The past years have seen an increasing debate on cooperation and its unique human character. Philosophers and psychologists have proposed that cooperative activities are characterized by shared goals to which participants are committed through the ability to understand each other’s intentions. Despite its popularity, some serious issues arise with this approach to cooperation. First, one may challenge the assumption that high-level mental processes are necessary for engaging in acting cooperatively. If they are, then how do agents that do not possess such ability (preverbal children, or children with autism who are often claimed to be mind-blind) engage in cooperative exchanges, as the evidence suggests? Secondly, to define cooperation as the result of two de-contextualized minds reading each other’s intentions may fail to fully acknowledge the complexity of situated, interactional dynamics and the interplay of variables such as the participants’ relational and personal history and experience. In this paper we challenge such accounts of cooperation, calling for an embodied approach that sees cooperation not only as an individual attitude toward the other, but also as a property of interaction processes. Taking an enactive perspective, we argue that cooperation is an intrinsic part of any interaction, and that there can be cooperative interaction before complex communicative abilities are achieved. The issue then is not whether one is able or not to read the other’s intentions, but what it takes to participate in joint action. From this basic account, it should be possible to build up more complex forms of cooperation as needed. Addressing the study of cooperation in these terms may enhance our understanding of human social development, and foster our knowledge of different ways of engaging with others, as in the case of autism.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Este trabalho versa sobre o universo da arte tangenciado pela moda, sua efemeridade, pertencimentos e seus agenciamentos. Nesse contexto, busca-se exemplificar o quanto a moda e a arte estão intrinsecamente ligadas. O ponto de partida é a moda como experiência e expressão coletiva e/ou individual, principalmente em trajes e formas vestimentares, pois são esses que mais forte influência exercem sobre o homem, seu corpo, seu espaço e memória. Localiza-se esse processo de aproximação entre arte e moda no século XX, quando vanguardas romperam com o academicismo clássico, agregando à arte sinestesias de sistemas relacionais. Rejeitam-se intermitências escultóricas e pictóricas para dar lugar a linguagens que interagem com o espectador. Os dados do presente trabalho traçam o panorama da aproximação entre arte e moda, a partir de duas vertentes: a primeira demonstra como a arte busca, no traje, suas sinergias, influenciando-se e apropriando-se da sinestesia proporcionada pela roupa; a segunda, como a moda apropriou-se de elementos da arte, em busca de um reposicionamento como expressão e não somente consumo