1,438 research outputs found

    Education and progression for support workers in mental health

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    Purpose: This case study details the development of a bespoke programme of learning for Support Workers employed in Mental Health sector. Design: The programme was designed to serve three purposes: to offer a route into Mental Health Nursing; to upskill those who wanted to remain as a Support Worker; to improve the quality of care provided. Findings: The paper shares the perspectives of the local Partnership Trust, a Support Worker on the programme and the Programme Director. Originality/Value: Employers within the Mental Health sector are encouraged to develop their own staff and Universities are urged to think differently about curriculum design

    Spectral radiometry and tropospheric aerosols: Report of panel

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    The term aerosols, as used here, refers to the haze, smoke, and dust that appear in the troposphere. The term does not refer to the hydrometeors in cumulus and stratus clouds but does include the sulfuric acid-water droplets which are assumed to predominate in the stratospheric aerosol layer. The aerosol properties that were measured from satellites and those which can be made in the near term (up to 1992) will be reviewed. The capabilities that will exist in the years 1992 to 2000, with implementation of EOS, are then discussed. Finally, a few words will be said concerning the potential for aerosol measurements for the decade after 2000

    Spontaneous thermal runaway as an ultimate failure mechanism of materials

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    The first theoretical estimate of the shear strength of a perfect crystal was given by Frenkel [Z. Phys. 37, 572 (1926)]. He assumed that as slip occurred, two rigid atomic rows in the crystal would move over each other along a slip plane. Based on this simple model, Frenkel derived the ultimate shear strength to be about one tenth of the shear modulus. Here we present a theoretical study showing that catastrophic material failure may occur below Frenkel's ultimate limit as a result of thermal runaway. We demonstrate that the condition for thermal runaway to occur is controlled by only two dimensionless variables and, based on the thermal runaway failure mechanism, we calculate the maximum shear strength σc\sigma_c of viscoelastic materials. Moreover, during the thermal runaway process, the magnitude of strain and temperature progressively localize in space producing a narrow region of highly deformed material, i.e. a shear band. We then demonstrate the relevance of this new concept for material failure known to occur at scales ranging from nanometers to kilometers.Comment: 4 pages, 3 figures. Eq. (6) and Fig. 2a corrected; added references; improved quality of figure

    Rate dependent shear bands in a shear transformation zone model of amorphous solids

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    We use Shear Transformation Zone (STZ) theory to develop a deformation map for amorphous solids as a function of the imposed shear rate and initial material preparation. The STZ formulation incorporates recent simulation results [Haxton and Liu, PRL 99 195701 (2007)] showing that the steady state effective temperature is rate dependent. The resulting model predicts a wide range of deformation behavior as a function of the initial conditions, including homogeneous deformation, broad shear bands, extremely thin shear bands, and the onset of material failure. In particular, the STZ model predicts homogeneous deformation for shorter quench times and lower strain rates, and inhomogeneous deformation for longer quench times and higher strain rates. The location of the transition between homogeneous and inhomogeneous flow on the deformation map is determined in part by the steady state effective temperature, which is likely material dependent. This model also suggests that material failure occurs due to a runaway feedback between shear heating and the local disorder, and provides an explanation for the thickness of shear bands near the onset of material failure. We find that this model, which resolves dynamics within a sheared material interface, predicts that the stress weakens with strain much more rapidly than a similar model which uses a single state variable to specify internal dynamics on the interface.Comment: 10 pages, 13 figures, corrected typos, added section on rate strengthening vs. rate weakening material

    LABOR LAW-JURISDICTION OF NLRB UNDER SELF-IMPOSED LIMITATIONS

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    Under the original National Labor Relations Act of 1935 and that act as it stands amended by Title I of the Labor-Management Relations Act of 1947, Congress has conferred upon the National Labor Relations Board regulatory authority in certain areas of industrial relations, the jurisdictional extent of which is conterminous with the power of the federal government under the commerce clause of the Constitution. At an early date, however, the Board determined that \u27\u27budgetary limitations as well as the need to avoid diffusion of its time and energy ... [justified] it in not exerting its jurisdictional authority to the legal hilt. Accordingly, the Board has consistently declined jurisdiction whenever in its estimation either a question of representation or an alleged unfair labor practice affects, but has no pronounced impact upon, interstate commerce

    Strain localization in a shear transformation zone model for amorphous solids

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    We model a sheared disordered solid using the theory of Shear Transformation Zones (STZs). In this mean-field continuum model the density of zones is governed by an effective temperature that approaches a steady state value as energy is dissipated. We compare the STZ model to simulations by Shi, et al.(Phys. Rev. Lett. 98 185505 2007), finding that the model generates solutions that fit the data,exhibit strain localization, and capture important features of the localization process. We show that perturbations to the effective temperature grow due to an instability in the transient dynamics, but unstable systems do not always develop shear bands. Nonlinear energy dissipation processes interact with perturbation growth to determine whether a material exhibits strain localization. By estimating the effects of these interactions, we derive a criterion that determines which materials exhibit shear bands based on the initial conditions alone. We also show that the shear band width is not set by an inherent diffusion length scale but instead by a dynamical scale that depends on the imposed strain rate.Comment: 8 figures, references added, typos correcte

    Higher comfort temperature preferences for anthropometrically matched Chinese and Japanese versus White-Western-Middle-European individuals using a personal comfort / cooling system

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    Purpose: To investigate potential differences in preferred Personal Comfort Systems (PCS) settings of Japanese and Han-Chinese versus white-western-middle-Europeans. Method: A series of five experiments with similar methodology is reported that allowed participants to self-select their preferred PCS outlet air temperature in a warm controlled climatic chamber setup with and without solar radiation. Test groups were matched for age, height, weight, body-surface-area and body-mass-index to remove the influence of these confounding factors on the results. Participants were first exposed to solar radiation (exp-1-4; simulating glazed building without proper shading or a car) before starting to control the outlet temperature of the PCS, or (exp-5, simulating warm building) were exposed to a warm room temperature and immediately could control the PCS. Ethnicity effects were studied through the chosen preferred PCS outlet temperatures and the microclimate temperature close to the participants’ chest. Results: In all experiments, Asian groups selected a PCS outlet temperature significantly higher, on average by 5 °C, leading to a 1.9 °C higher microclimate temperature at chest level. While absolute selected temperatures of the PCS differed between experiments, related to different designs of the PCS and climate conditions, no interaction between ethnicity and experiment was present. Conclusions: Despite removing important confounding factors that could explain earlier observed differences between Asian and white western middle-European ethnicities tested, a substantial, consistently higher thermal preference temperature of the PCS was found in the two Asian groups. This has implications for the design parameters of PCS for use in offices or air-conditioning systems in cars

    Anti-Pasch optimal packings with triples

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    It is shown that for v ≠ 6, 7, 10, 11, 12, 13, there exists an optimal packing with triples on v points that contains no Pasch configurations. Furthermore, for all v ≡ 5 (mod 6), there exists a pairwise balanced design of order v, whose blocks are all triples apart from a single quintuple, and that has no Pasch configurations amongst its triples

    Spontaneous dissipation of elastic energy by self-localizing thermal runaway

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    Thermal runaway instability induced by material softening due to shear heating represents a potential mechanism for mechanical failure of viscoelastic solids. In this work we present a model based on a continuum formulation of a viscoelastic material with Arrhenius dependence of viscosity on temperature, and investigate the behavior of the thermal runaway phenomenon by analytical and numerical methods. Approximate analytical descriptions of the problem reveal that onset of thermal runaway instability is controlled by only two dimensionless combinations of physical parameters. Numerical simulations of the model independently verify these analytical results and allow a quantitative examination of the complete time evolutions of the shear stress and the spatial distributions of temperature and displacement during runaway instability. Thus we find that thermal runaway processes may well develop under nonadiabatic conditions. Moreover, nonadiabaticity of the unstable runaway mode leads to continuous and extreme localization of the strain and temperature profiles in space, demonstrating that the thermal runaway process can cause shear banding. Examples of time evolutions of the spatial distribution of the shear displacement between the interior of the shear band and the essentially nondeforming material outside are presented. Finally, a simple relation between evolution of shear stress, displacement, shear-band width and temperature rise during runaway instability is given.Comment: 16 pages, 7 figures. Extended conclusion; added reference
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