1,448 research outputs found

    This is What Democracy Looks Like

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    These remarks were prepared for the Partnership for the Public Good\u27s Tenth Anniversary Celebration on October 5, 2017 at the Albright-Knox Art Gallery

    An experimental study of the effect of high-pressure water jet assisted turning (HPWJAT) on the surface integrity

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    This study deals with the effect of High-Pressure Water Jet Assisted Turning (HPWJAT) of austenitic stainless steels on chip shape and residual stresses. The machining of the austenitic stainless steels represents several difficulties. Recently, research has shown that the introduction of a high-pressure water jet into the gap between the tool and the chip interface is a very satisfactory method for machining applications. In this article, the effect of a high-pressure water jet, directed into the tool–chip interface, on chip shapes breakage and surface integrity in face turning operations of AISI 316L steel has been investigated. Tests have been carried out with a standard cutting tool. The cutting speeds used were 80 and 150 m/min, with a constant feed rate of 0.1 mm/rev and a constant cutting depth of 1 mm. Three jet pressures were used: 20, 50 and 80 MPa. Residual stress profiles have been analysed using the X-ray diffraction method in both longitudinal and transversal directions. The results show that jet pressure and cutting parameters influence the residual stresses and the chip shapes. Using a high-pressure jet, it is possible to create a well fragmented chip in contrast to the continuous chip formed using dry turning. It is also possible to control the chip shape and increase tool life. When the jet pressure is increased the residual stress at the surface decreases; however it is increased by an increase in cutting speed. It can be concluded that surface residual stresses can be reduced by the introduction of a high-pressure water jet

    Labor Takes the High Road: How Unions Make Western New York More Prosperous and Equitable

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    The report explores how unions make a major impact on the region not just through collective bargaining, but also through community service and policy advocacy. Analyzing Census data, the authors find that union members in Western New York enjoy substantially higher wages, more full-time work, more health insurance coverage, and more pension benefits than non-members. Union impacts radiate out far beyond their members. Research reveals that unions improve wages, job quality, health, and safety, for other workers as well. Unions support community efforts with volunteer hours and donations, and they play a critical role in workforce development and training. Finally, organized labor advocates for high road public policies regarding issues such as civil rights, public health, and responsible economic development

    Labor and Urban Crisis in Buffalo, New York: Building a High Road Infrastructure

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    With inequality growing and competitive market forces on the march, can unions play a constructive role in solving the problems of capitalist economic development? Should they try? In this study of coalition building in Buffalo, New York we find that regular procedures of problem solving involving multiple coalition partners – what we call a high-road social infrastructure – have developed in the city. We discuss the progression of union approaches to economic development, including in-plant and regional labor-management partnership, community coalitions and the creation of labor-led nonprofit organizations. In response to long-term economic and social crisis, a group of union leaders has begun carrying out projects to help attract investment from outside the region and improve the quality of jobs in the region. Coalition-building, however, is hampered by uncertainty about the best union strategy, enmity from some business and political elites, and the scale of the region’s long-term structural problems

    Buffalo Child Care Means Business: Executive Summary

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    [Excerpt] This study of child care needs and opportunities in downtown Buffalo includes original empirical evidence from a representative survey of employers in core zip codes 14201-2-3-4. The Survey Research Institute of Cornell University conducted the telephone survey of chief operating officers or human resource directors of 117 employers in the spring of 2006. The data pool was scientifically balanced to include small, medium, and large employers from both the public and private sectors as well as all child care employers within the geographic area of the study. Highlights of the findings are included here

    Comprehension of chip formation in laser assisted machining

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    Laser Assisted Machining (LAM) improves the machinability of materials by locally heating the workpiece just prior to cutting. Experimental investigations have confirmed that the cutting force can be decreased, by as much as 40%, for various materials. In order to understand the effect of the laser on chip formation and on the temperature fields in the different deformation zones, thermo-mechanical simulations were undertaken. A thermo-mechanical model for chip formation was also undertaken. Experimental tests for the orthogonal cutting of 42CrMo4 steel were used to validate the simulation. The temperature fields allow us to explain the reduction in the cutting force and the resulting residual stress fields in the workpiece.Contrat Plan Etat RĂ©gion (CPER) Pays de la Loir

    The COBRAS/SAMBA CMB Project

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    COBRAS/SAMBA is a second generation satelitte dedicated to mapping at high resolution and sensitivity the anisotropies of the Cosmic Microwave Background (CMB). This mission is in the assessment study phase (A) at ESA, with a decision expected mid 1996, for a launch around 2003.Comment: PostScript, 4 pages, 4 figures in text, to appear in the Proceedings of the 1995 Moriond Meeting on ``Clustering in the Universe'

    A Biaxial Fatigue Specimen for Uniaxial Loading

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    The aim of this paper is to present a novel un-notched fatigue test specimen in which a biaxial stress state is achieved using a uniaxial loading condition. This allows the problem of multi-axial fatigue to be studied using relatively common one-axis servo-hydraulic testing machines. In addition the specimen presented here is very compact and can be made using a small volume of material (100x40x4.5mm). For this specimen, the degree of biaxiality, defined by the parameter is equal to approximately 0.45. The specimen geometry was optimised using the Dang Van multi-axial fatigue criterion. In addition to use as a fatigue specimen, it has been demonstrated that the biaxial specimen presented here is also suitable for biaxial tensile tests, to determine the rupture strength of a material in a biaxial stress state. Two different materials have been investigated: The first was wrought aluminium 2024-O in the form of 5mm sheets. The second was a cast aluminium-silicon alloy AlSi7Cu0.5Mg0.3, commonly used in automotive and aeronautical applications. The fatigue strengths were determined at 2x106 cycles and at various R-ratios using a staircase procedure. For the aluminium 2024, it is shown that the biaxial stress state increases the maximum permissible first principal stress when compared to the uniaxial condition. However, in terms of the cast aluminium alloy, it has been demonstrated that this type of fatigue specimen is not suitable for materials containing casting defects, in particular micro-shrinkage pores, because the volume of material, in which the stress state is biaxial, is not large enough.The authors gratefully acknowledge the financial support of PSA – Peugeot CitroĂ«n and also that of the Conseil GĂ©nĂ©ral du DĂ©partement de Maine-et-Loire, France

    Merging enriched Finite Element triangle meshes for fast prototyping of alternate solutions in the context of industrial maintenance

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    A new approach to the merging of Finite Element (FE) triangle meshes is proposed. Not only it takes into account the geometric aspects, but it also considers the way the semantic information possibly associated to the groups of entities (nodes, faces) can be maintained. Such high level modification capabilities are of major importance in all the engineering activities requiring fast modifications of meshes without going back to the CAD model. This is especially true in the context of industrial maintenance where the engineers often have to solve critical problems in very short time. Indeed, in this case, the product is already designed, the CAD models are not necessarily available and the FE models might be tuned. Thus, the product behaviour has to be studied and improved during its exploitation while prototyping directly several alternate solutions. Such a framework also finds interest in the preliminary design phases where alternative solutions have to be simulated. The algorithm first removes the intersecting faces in an n-ring neighbourhood so that the filling of the created holes produces triangles whose sizes smoothly evolve according to the possibly heterogeneous sizes of the surrounding triagles. The holefilling algorithm is driven by an aspect ratio factor which ensures that the produced triangulation fits well the FE requirements. It is also constrained by the boundaries of the groups of entities gathering together the simulation semantic. The filled areas are then deformed to blend smoothly with the surroundings meshes
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