An idea unleashed in history: Dr Martin Luther King Jr and the campaign to end poverty in America

A range of learning opportunities helped to prepare and educate thousands of activists to participate in American civil rights movement campaigns in the 1960s. The adult learning approaches adopted by civil rights activists represented alternatives to conventional educational practices. Adult education was particularly significant in 1968, during what was to become Dr Martin Luther King’s final initiative, the Poor People’s Campaign (PPC). The PPC saw thousands of poor people travel to Washington DC to protest against poverty and to demand legislation which would address economic injustice in the United States. The demonstrators occupied sacred space in Washington DC by building a temporary community, known as Resurrection City. The PPC drew from a rich legacy of adult learning in previous civil rights campaigns including voter registration initiatives. On the journey to the nation’s capital and in Resurrection City itself, Freedom Schools, workshops and demonstrations assisted the protesters to come together in coalition to challenge dominant hegemonic narratives concerning the causes, nature and scope of poverty. The PPC also performed an important public pedagogical role in dramatising the issue of poverty in the United States. Although ultimately unsuccessful in its aspiration to end economic injustice in America, the PPC undoubtedly laid the seeds for future anti-poverty activism. The article draws from five archives

The Illinois State Library on-line circulation control system

"On-Line" circulation control has been a reality at the Illinois State Library since late in 1966. It would be incorrect, of course, to think that this was accomplished overnight or instantaneously. Such was decidedly not the case. Beginning as early as 1959, many hours of discussion and planning were required by the office of Secretary of State and its collaborating Drivers License Division and Illinois State Library staff members.published or submitted for publicatio

Gross plastic deformation of axisymmetric pressure vessel heads

The gross plastic deformation and associated plastic loads of four axisymmetric torispherical pressure vessels are determined by two criteria of plastic collapse: the ASME twice elastic slope (TES) criterion and the recently proposed plastic work curvature (PWC) criterion. Finite element analysis was performed assuming small and large deformation theory and elastic–perfectly plastic and bilinear kinematic hardening material models. Two plastic collapse modes are identified: bending-dominated plastic collapse of the knuckle region in small deformation models and membrane-dominated plastic collapse of the cylinder or domed end in large deformation models. In both circumstances, the PWC criterion indicates that a plastic hinge bending mechanism leads to gross plastic deformation and is used as a parameter to identify the respective plastic loads. The results of the analyses also show that the PWC criterion leads to higher design loads for strain hardening structures than the TES criterion, as it takes account of the effect of strain hardening on the evolution of the gross plastic deformation mechanism

Design by analysis of ductile failure and buckling in torispherical pressure vessel heads

Thin shell torispherical pressure vessel heads are known to exhibit complex elastic-plastic deformation and buckling behaviour under static pressure. In pressure vessel Design by Analysis, the designer is required to assess both of these behaviour modes when specifying the allowable static load. The EN and ASME boiler and pressure vessel codes permit the use of inelastic analysis in design by analysis, known as the direct route in the EN Code. In this paper, plastic collapse or gross plastic deformation loads are evaluated for two sample torispherical heads by 2D and 3D FEA based on an elastic-perfectly plastic material model. Small and large deformation effects are considered in the 2D analyses and the effect of geometry and load perturbation are considered in the 3D analysis. The plastic load is determined by applying the ASME twice elastic slope criterion of plastic collapse and an alternative plastic criterion, the Plastic Work Curvature criterion. The formation of the gross plastic deformation mechanism in the models is considered in relation to the elastic-plastic buckling response of the vessels. It is concluded that in both cases, design is limited by formation of an axisymmetric gross plastic deformation in the knuckle of the vessels prior to formation of non-axisymmetric buckling modes

Multiphysics models for friction stir welding simulation

Purpose: The Friction Stir Welding (FSW) process comprises of several highly coupled (and non-linear) physical phenomena: large plastic deformation, material flow transportation, mechanical stirring of the tool, tool-workpiece surface interaction, dynamic structural evolution, heat generation from friction and plastic deformation, etc. In this paper, an advanced Finite Element (FE) model encapsulating this complex behavior is presented and various aspects associated with the FE model such as contact modeling, material model and meshing techniques are discussed in detail. Methodology: The numerical model is continuum solid mechanics-based, fully thermomechanically coupled and has successfully simulated the friction stir welding process including plunging, dwelling and welding stages. Findings: The development of several field variables are quantified by the model: temperature, stress, strain, etc. Material movement is visualized by defining tracer particles at the locations of interest. The numerically computed material flow patterns are in very good agreement with the general findings from experiments. Value: The model is, to the best of the authors’ knowledge, the most advanced simulation of FSW published in the literature

Plastic load evaluation for a fixed tube sheet heat exchanger subject to proportional loading

The plastic load of pressurised components can be calculated based on both the twice elastic slope and tangent methods. Both methods are problematic since they rely on parameters that are localised and therefore have a strong dependency on the gradient of the stress–strain diagram in the plastic region. The criterion of curvature of plastic work is a suitable replacement for the above techniques. This method calculates total plastic work done on the structure and relates its change to the curvature of the load-plastic work plot. In this work the plastic load has been calculated for a fixed tube sheet exchanger according to curvature criteria using various hardening scenarios. Plastic loads calculated by other methods also have been reported. It has been indicated that tube sheet thickness calculated according to the classical ASME procedure can be significantly reduced when based on the curvature criteria

Slotting Allowances and Retail Product Variety under Oligopoly

Slotting fees are fixed charges paid by food manufacturers to retailers for access to the retail market. The role of the practice and its effects on market efficiency are highly controversial. To date, the literature has focused on the effect of the practice on retail prices; however, slotting allowances also have the potential to alter the range of products available to consumers. Our analysis reveals that the strategic use of slotting allowances by oligopoly firms leads to a superior allocation of product variety among retailers. Indeed, absent price effects, we show that slotting allowances lead to the socially optimal provision of product variety.Slotting fees, vertical contracts, monopolization., Agribusiness, Agricultural and Food Policy, Industrial Organization, Marketing, L13, L14, L42, D43,

Numerical simulation of ratcheting and fatigue behaviour of mitred pipe bends under in-plane bending and internal pressure

This paper investigates the ratcheting and fatigue behaviour of 90 degree single unreinforced mitred pipe bends subjected to a cyclic in-plane closing moment with a non-zero mean value and constant internal pressure. An experiment was conducted to induce ratcheting and low cycle failure of the mitred pipe bend. Material and structural response is considered both locally and globally using strain gauges at the locations of highest strain and also by measuring the displacement of the mitre end. These results along with the number of cycles to failure are compared with those produced from nonlinear finite element analysis. The predicted crosshead displacement from the multi linear model showed a good agreement with the test results. However, the finite element model failed to accurately replicate the strain level or trend from the tests, indicating the weakness of the material model used in simulating the cyclic hardening effect. It was also found that the FE models proposed were not able to model the final failure mode of the mitre due to the exclusion of crack simulation in the analysis, i.e. interaction between ratcheting and low cycle fatigue cracking was not considered in the idealised numerical model

The 2D Distribution of Iron Rich Ejecta in the Remnant of SN 1885 in M31

We present Hubble Space Telescope (HST) ultraviolet Fe I and Fe II images of the remnant of Supernova 1885 (S And) which is observed in absorption against the bulge of the Andromeda galaxy, M31. We compare these Fe I and Fe II absorption line images to previous HST absorption images of S And, of which the highest quality and theoretically cleanest is Ca II H & K. Because the remnant is still in free expansion, these images provide a 2D look at the distribution of iron synthesized in this probable Type Ia explosion, thus providing insights and constraints for theoretical SN Ia models. The Fe I images show extended absorption offset to the east from the remnant's center as defined by Ca II images and is likely an ionization effect due to self-shielding. More significant is the remnant's apparent Fe II distribution which consists of four streams or plumes of Fe-rich material seen in absorption that extend from remnant center out to about 10,000 km/s. This is in contrast to the remnant's Ca II absorption, which is concentrated in a clumpy, roughly spherical shell at 1000 to 5000 km/s but which extends out to 12,500 km/s. The observed distributions of Ca and Fe rich ejecta in the SN 1885 remnant are consistent with delayed detonation white dwarf models. The largely spherical symmetry of the Ca-rich layer argues against a highly anisotropic explosion as might result from a violent merger of two white dwarfs.Comment: 14 pages, 8 figures, and 1 table; revised to match ApJ published versio