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Sample records for work hardening program

  1. Working hardening modelization in zirconium alloys

    International Nuclear Information System (INIS)

    Sanchez, P.; Pochettino, Alberto A.

    1999-01-01

    Working hardening effects on mechanical properties and crystallographic textures formation in Zr-based alloys are studied. The hardening mechanisms for different grain deformations and topological conditions of simple crystal yield are considered. Results obtained show that the differences in the cold rolling textures (L and T textures) can be related with hardening microstructural parameters. (author)

  2. The microstructural origin of work hardening stages

    DEFF Research Database (Denmark)

    Hughes, D. A.; Hansen, N.

    2018-01-01

    The strain evolution of the flow stress and work hardening rate in stages III and IV is explored by utilizing a fully described deformation microstructure. Extensive measurements by transmission electron microscopy reveal a hierarchical subdivision of grains by low angle incidental dislocation...... addition of the classical Taylor and Hall-Petch formulations. Model predictions agree closely with experimental values of flow stress and work hardening rate in stages III and IV. Strong connections between the evolutionary stages of the deformation microstructure and work hardening rates create a new...... (modern) basis for the classic problem of work hardening in metals and alloys. These connections lead the way for the future development of ultra high strength ductile metals produced via plastic deformation.(c) 2018 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved....

  3. Numerical and experimental comparison of plastic work-hardening rules

    International Nuclear Information System (INIS)

    Haisler, W.E.

    1977-01-01

    The purpose of this paper is to describe recent numerical and experimental correlation studies of several plastic work-hardening rules. The mechanical sublayer model and the combined kinematic-isotropic hardening rules are examined and the numerical results for several structural geometries are compared to experimental results. Both monotonic and cyclic loads are considered. The governing incremental plasticity relations are developed for both work-hardening models. The combined kinematic-isotropic hardening model is developed in terms of a ratio γ which controls the relative contribution of kinematic hardening (yield surface translation) and isotropic hardening (yield surface expansion). In addition to making use of a uniaxial stress-strain curve as input data, the model allows for the input of a yield surface size vs. uniaxial plastic strain curve obtained from a cyclic uniaxial reverse loading test. The mechanical sublayer model is developed in general form and a new method for determining the sublayer parameters (stress weighting factors and yield stresses) is presented. It is demonstrated that former procedures used to obtain the sublayer parameters are inconsistent for multiaxial loading. Numerical and experimental results are presented for a cylinder, circular plate with punch, and a steel pressure vessel. The numerical results are obtained with the computer program AGGIE I. The comparison study indicates that reasonable agreement is obtained with both hardening models; the choice depending upon whether the loading is monotonic or cyclic

  4. Work hardening correlation for monotonic loading based on state variables

    International Nuclear Information System (INIS)

    Huang, F.H.; Li, C.Y.

    1977-01-01

    An absolute work hardening correlation in terms of the hardness parameter and the internal stress based on the state variable approach was developed. It was found applicable to a variety of metals and alloys. This correlation predicts strain rate insensitive work hardening properties at low homologous temperatures and produces strain rate effects at higher homologous temperatures without involving thermally induced recovery processes

  5. Analysis of the work-hardening process in spheroidized steels

    International Nuclear Information System (INIS)

    Pacheco, J.L.

    1981-07-01

    An elementary model for the work-hardening process in duplex-structures steels (ferrite - spheroidite) is proposed and tested on low, medium and high carbon content, which seems to give good results concerning the influence of the volume fraction and particle size of the second phase on the work-hardening behaviour. (Author) [pt

  6. Work hardening behavior study of structural alloys for cryogenic applications

    International Nuclear Information System (INIS)

    Chu, D.; Morris, J.W. Jr.

    1992-01-01

    Previous investigation on aluminum-lithium alloys have indicated different dependencies of the work hardening behavior on temperature. This variation in temperature dependence is attributed to differences in microstructure rather than composition. An understanding of the microstructural effect on the observed thermal dependency is important as it may allow the tailoring of deformation properties through mechanical processing. Work hardening analyses on other aluminum alloys and a number of structural steels have been performed to better elucidate the role played by microstructure in determining the work hardening behavior. In the paper correlations between the differences in mechanical behavior and the various microstructures observed are presented

  7. A review of the stages of work hardening

    Energy Technology Data Exchange (ETDEWEB)

    Rollett, A.D.; Kocks, U.F.

    1993-07-01

    Stages of work hardening are reviewed with emphasis on links between each stage. Simple quantitative descriptions are given for each stage. Similarities between stage I, easy glide, and stage IV, large strain hardening, are pointed out both in terms of magnitude of the hardening rate and of the underlying mechanism of dislocation debris accumulation. Stage II is described as an athermal hardening stage that occurs when statistical variations in the dislocation ``forest`` lead to geometrical storage of dislocations. The steadily decreasing hardening rate observed in stage III is characterized by the increasing rate of loss of dislocation density due to dynamic recovery. Stage III appears to have an asymptote to a saturation stress which is determined by the characteristics of the dislocation tangles, or cell walls. The imperfect nature of the dynamic recovery process, however, leads to the accumulation of dislocation debris and this, by analogy with stage 1, causes the apparent saturation stress to rise, thus causing stage IV.

  8. Generation Mechanism of Work Hardened Surface Layer in Metal Cutting

    Science.gov (United States)

    Hikiji, Rikio; Kondo, Eiji; Kawagoishi, Norio; Arai, Minoru

    Finish machining used to be carried out in grinding, but it is being replaced by cutting with very small undeformed chip thickness. In ultra precision process, the effects of the cutting conditions and the complicated factors on the machined surface integrity are the serious problems. In this research, work hardened surface layer was dealt with as an evaluation of the machined surface integrity and the effect of the mechanical factors on work hardening was investigated experimentally in orthogonal cutting. As a result, it was found that work hardened surface layer was affected not only by the shear angle varied under the cutting conditions and the thrust force of cutting resistance, but also by the thrust force acting point, the coefficient of the thrust force and the compressive stress equivalent to the bulk hardness. Furthermore, these mechanical factors acting on the depth of the work hardened surface layer were investigated with the calculation model.

  9. Disorientations and work-hardening behaviour during severe plastic deformation

    DEFF Research Database (Denmark)

    Pantleon, Wolfgang

    2012-01-01

    Orientation differences develop during plastic deformation even in grains of originally uniform orientation. The evolution of these disorientations is modelled by dislocation dynamics taking into account different storage mechanisms. The predicted average disorientation angles across different ty...... pressure torsion, but also rationalizes the work-hardening behaviour at large plastic strains as well as a saturation of the flow stress....

  10. Coefficient of work-hardening in stage-IV

    CSIR Research Space (South Africa)

    Nabarro, FRN

    1994-04-15

    Full Text Available The theory of work hardening in stage IV depends on the relation between the relative misorientation Psi of neighbouring subgrains and the plastic strain gamma (Psi = B gamma exp). The value of the constant B is suggested to be better related...

  11. Role of work hardening characteristics of matrix alloys in the ...

    Indian Academy of Sciences (India)

    Unknown

    with increasing prismatic punching of dislocations in the order 7075, 2014, 7010, 2024, 6061 and commercial purity aluminium leading to increased strength increments is noted. Keywords. Metal matrix composites; strengthening; work hardening rate; dislocation density. 1. Introduction. While in continuous fibre composites, ...

  12. work hardening, recovery and recrystallization of alloys containing dispersed precipitates

    International Nuclear Information System (INIS)

    Padilha, A.F.

    1989-01-01

    This paper reviews the work hardening, recovery and recrystallization mechanisms in alloys containing dispersed precipitates. In the section on work hardening, the influence od spacing, particle size and shape on the density and distribution of dislocations have been discussed. They represent a large part of the energy stored in the material following drformation, which in turn is driving force for recrystallization. Next, the role of precipitates on recovery, on the formation and the growth of recrystallized regions has been discussed in detail. The competition between recovery and recrystallization and recrystallization of supersaturated solid solutions have also been mentioned. Finally, the technological relevance of the aspects treated in this paper has been discussed. (author) [pt

  13. Significance of rate of work hardening in tempered martensite embrittlement

    International Nuclear Information System (INIS)

    Pietikainen, J.

    1995-01-01

    The main explanations for tempered martensite embrittlement are based on the effects of impurities and cementite precipitation on the prior austenite grain boundaries. There are some studies where the rate of work hardening is proposed as a potential reason for the brittleness. One steel was studied by means of a specially developed precision torsional testing device. The test steel had a high Si and Ni content so ε carbide and Fe 3 C appear in quite different tempering temperature ranges. The M S temperature is low enough so that self tempering does not occur. With the testing device it was possible to obtain the true stress - true strain curves to very high deformations. The minimum toughness was always associated with the minimum of rate of work hardening. The change of deformed steel volume before the loss of mechanical stability is proposed as at least one reason for tempered martensite embrittlement. The reasons for the minimum of the rate of work hardening are considered. (orig.)

  14. Temperature dependence of work hardening in sparsely twinning zirconium

    International Nuclear Information System (INIS)

    Singh, Jaiveer; Mahesh, S.; Roy, Shomic; Kumar, Gulshan; Srivastava, D.; Dey, G.K.; Saibaba, N.; Samajdar, I.

    2017-01-01

    Fully recrystallized commercial Zirconium plates were subjected to uniaxial tension. Tests were conducted at different temperatures (123 K - 623 K) and along two plate directions. Both directions were nominally unfavorable for deformation twinning. The effect of the working temperature on crystallographic texture and in-grain misorientation development was insignificant. However, systematic variation in work hardening and in the area fraction and morphology of deformation twins was observed with temperature. At all temperatures, twinning was associated with significant near boundary mesoscopic shear, suggesting a possible linkage with twin nucleation. A binary tree based model of the polycrystal, which explicitly accounts for grain boundary accommodation and implements the phenomenological extended Voce hardening law, was implemented. This model could capture the measured stress-strain response and twin volume fractions accurately. Interestingly, slip and twin system hardness evolution permitted multiplicative decomposition into temperature-dependent, and accumulated strain-dependent parts. Furthermore, under conditions of relatively limited deformation twinning, the work hardening of the slip and twin systems followed two phenomenological laws proposed in the literature for non-twinning single-phase face centered cubic materials.

  15. Ductility and work hardening in nano-sized metallic glasses

    Energy Technology Data Exchange (ETDEWEB)

    Chen, D. Z., E-mail: dzchen@caltech.edu [Division of Engineering and Applied Sciences, California Institute of Technology, Pasadena, California 91125 (United States); Gu, X. W. [Department of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125 (United States); An, Q.; Goddard, W. A. [Materials and Process Simulation Center, California Institute of Technology, Pasadena, California 91125 (United States); Greer, J. R. [Division of Engineering and Applied Sciences, California Institute of Technology, Pasadena, California 91125 (United States); The Kavli Nanoscience Institute, California Institute of Technology, Pasadena, California 91125 (United States)

    2015-02-09

    In-situ nano-tensile experiments on 70 nm-diameter free-standing electroplated NiP metallic glass nanostructures reveal tensile true strains of ∼18%, an amount comparable to compositionally identical 100 nm-diameter focused ion beam samples and ∼3 times greater than 100 nm-diameter electroplated samples. Simultaneous in-situ observations and stress-strain data during post-elastic deformation reveal necking and work hardening, features uncharacteristic for metallic glasses. The evolution of free volume within molecular dynamics-simulated samples suggests a free surface-mediated relaxation mechanism in nano-sized metallic glasses.

  16. Strain path and work-hardening behavior of brass

    International Nuclear Information System (INIS)

    Sakharova, N.A.; Fernandes, J.V.; Vieira, M.F.

    2009-01-01

    Plastic straining in metal forming usually includes changes of strain path, which are frequently not taken into account in the analysis of forming processes. Moreover, strain path change can significantly affect the mechanical behavior and microstructural evolution of the material. For this reason, a combination of several simple loading test sequences is an effective way to investigate the dislocation microstructure of sheet metals under such forming conditions. Pure tension and rolling strain paths and rolling-tension strain path sequences were performed on brass sheets. A study of mechanical behavior and microstructural evolution during the simple and the complex strain paths was carried out, within a wide range of strain values. The appearance and development of deformation twinning was evident. It was shown that strain path change promotes the onset of premature twinning. The work-hardening behavior is discussed in terms of the twinning and dislocation microstructure evolution, as revealed by transmission electron microscopy

  17. Work-hardening of dual-phase steel

    Energy Technology Data Exchange (ETDEWEB)

    Rieger, Florian

    2016-07-01

    Exhibiting good mechanical properties for cold-sheet forming, low-alloyed dual-phase (DP) steels are nowadays widely used for automotive applications. The composite-like microstructure of DP steels is composed of a low-carbon ductile ferrite-matrix and 10 - 60 vol.% hard martensitic inclusions. A nonlinear mean-field model and full-field finite-element simulations are applied to investigate three major topics: the influence of grain-size distribution, grain-level plasticity and derivation of an original material-model. The plastic behavior of polycrystals is assumed to be grain-size dependent in this work. The distribution of grain-sizes is taken to be lognormal. It is found that grain-size dispersion leads to a decrease of the material strength, in particular for small mean diameters around one micron. The numerical results from the mean-field model are confirmed notably well by means of a simple analytical expression. The micromechanical behavior of DP steels is investigated by full-field RVE simulations with a crystal-plasticity based ferrite-matrix and von Mises-type martensite inclusions. To examine the martensite influence, full-field simulation results of DP steels have been compared to an RVE in which martensite is substituted by ferrite. After quenching, a higher grain-boundary area covered by martensite facilitates an increased average dislocation-density. For uniaxial deformations above ∝10%, however, the grain-size dependent relation reverses. With more surrounding martensite, the local crystal-plasticity material-model exhibits hardening at a slower rate. A nonlinear mean-field model of Hashin-Shtrikman type is employed as framework for the original material-model for DP steels. The model incorporates the interaction of ferrite and martensite via incompatibility-induced long-range stresses in an averaged sense. The proposed model combines works of Ashby (1970) and Brown and Stobbs (1971a) to simulate the ferrite behavior. Based on the composite model

  18. Numerical analysis of drilling hole work-hardening effects in hole-drilling residual stress measurement

    Science.gov (United States)

    Li, H.; Liu, Y. H.

    2008-11-01

    The hole-drilling strain gage method is an effective semi-destructive technique for determining residual stresses in the component. As a mechanical technique, a work-hardening layer will be formed on the surface of the hole after drilling, and affect the strain relaxation. By increasing Young's modulus of the material near the hole, the work-hardening layer is simplified as a heterogeneous annulus. As an example, two finite rectangular plates submitted to different initial stresses are treated, and the relieved strains are measured by finite element simulation. The accuracy of the measurement is estimated by comparing the simulated residual stresses with the given initial ones. The results are shown for various hardness of work-hardening layer. The influence of the relative position of the gages compared with the thickness of the work-hardening layer, and the effect of the ratio of hole diameter to work-hardening layer thickness are analyzed as well.

  19. Method for determining the work hardening function to describe plasticity of metals

    International Nuclear Information System (INIS)

    Wilkins, M.L.

    1978-01-01

    A method for obtaining a constitutive relation that relates the flow stress to the equivalent plastic strain is developed. The method uses simple tension test data to suggest a functional form. This form is then used as a constitutive model in a computer program that simulates the tension test. The calculated results are compared with the experimental results and the functional form is refined until agreement is obtained between calculations and experiments. The importance of knowing the relationship between the flow stress and the plastic strain is discussed. A work hardening function is calibrated for 6061 T6 aluminum

  20. Work hardening and plastic equation of state of tantalum

    International Nuclear Information System (INIS)

    Gypen, L.A.; Aernoudt, E.; Deruyttere, A.

    1983-01-01

    The influence of cold deformation on the thermal and athermal components of the flow stress of tantalum was investigated. Up to high deformation levels the strain hardening is due only to the development of internal stress fields; the effective stress remains almost constant. The athermal strain hardening of tantalum is parabolic at low deformation levels (epsilon < 0.5) and linear at high deformation levels, as for other bcc metals. Hart's plastic equation of state is shown to be valid for tantalum at room temperature in the whole deformation range investigated (from epsilon = 0.005 to epsilon = 2.8). (author)

  1. Applicability of Voce equation for tensile flow and work hardening behaviour of P92 ferritic steel

    International Nuclear Information System (INIS)

    Sainath, G.; Choudhary, B.K.; Christopher, J.; Isaac Samuel, E.; Mathew, M.D.

    2015-01-01

    Detailed analysis of true stress (σ)-true plastic strain (ε) data indicated that tensile flow behaviour of P92 ferritic steel can be adequately described by Voce equation at strain rates ranging from 3.16 × 10 −5 to 1.26 × 10 −3  s −1 over a temperature range 300–923 K. The steel exhibited two-stage work hardening in the variations of instantaneous work hardening rate (θ = dσ/dε) with stress. At all the strain rates, the variations in σ-ε, θ-σ and work hardening parameters associated with Voce equation with temperature exhibited three distinct temperature regimes. At intermediate temperatures, the variations in σ-ε, θ-σ and work hardening parameters with temperature and strain rate exhibited anomalous behaviour due to the occurrence of dynamic strain ageing in the steel. The shift in θ-σ towards low stresses, and rapid decrease in flow stress and work hardening parameters with increasing temperature and decreasing strain rate suggested dominance of dynamic recovery at high temperatures. - Highlights: • Tensile flow and work hardening behaviour of P92 steel has been examined. • Applicability of Voce equation to P92 steel is demonstrated. • Three temperature regimes in flow and work hardening has been observed. • Good match between predicted and the experimental tensile properties has been shown

  2. Characterization of the work hardening structure of austenitic steels by X-ray diffraction. Application to the determination of work hardening gradients and the study of recovery

    International Nuclear Information System (INIS)

    Cadalbert, Robert; Baron, J.L.

    1977-01-01

    A method has been developed to determine quantitatively the work hardening of austenitic steels by measurement of the broadening of X-ray diffraction lines. This simple, rapid, accurate and sensible method enables to determine work hardening variations in the thickness of a material. The complete automation of the measurement cycle using a small computer enables to carry out numerous determinations and to process data with accuracy. The unit developed is well adapted to the testing of metallic materials. It is also possible with this method to study the evolution of work hardening in a metal as a function of heat treatments. For instance, the determination of the recovery curves of the crystal lattice in austenitic steels allows to investigate the influence of additions (Mo, Ti) on the recovery kinetics [fr

  3. Unit rupture work as a criterion for quantitative estimation of hardenability in steel

    International Nuclear Information System (INIS)

    Kramarov, M.A.; Orlov, E.D.; Rybakov, A.B.

    1980-01-01

    Shown is possible utilization of high sensitivity of resistance to fracture of structural steel to the hardenability degree in the course of hardening to find the quantitative estimation of the latter one. Proposed is a criterion kappa, the ratio of the unit rupture work in the case of incomplete hardenability (asub(Tsub(ih))) under investigation, and the analoguc value obtained in the case of complete hardenability Asub(Tsub(Ch)) at the testing temperature corresponding to the critical temperature Tsub(100(M). Confirmed is high criterion sensitivity of the hardened steel structure on the basis of experimental investigation of the 40Kh, 38KhNM and 38KhNMFA steels after isothermal hold-up at different temperatures, corresponding to production of various products of austenite decomposition

  4. Work Hardening Behavior of 1020 Steel During Cold-Beating Simulation

    Science.gov (United States)

    CUI, Fengkui; LING, Yuanfei; XUE, Jinxue; LIU, Jia; LIU, Yuhui; LI, Yan

    2017-03-01

    The present research of cold-beating formation mainly focused on roller design and manufacture, kinematics, constitutive relation, metal flow law, thermo-mechanical coupling, surface micro-topography and microstructure evolution. However, the research on surface quality and performance of workpieces in the process of cold-beating is rare. Cold-beating simulation experiment of 1020 steel is conducted at room temperature and strain rates ranging from 2000 to 4000 s-1 base on the law of plastic forming. According to the experimental data, the model of strain hardening of 1020 steel is established, Scanning Electron Microscopy(SEM) is conducted, the mechanism of the work hardening of 1020 steel is clarified by analyzing microstructure variation of 1020 steel. It is found that the strain rate hardening effect of 1020 steel is stronger than the softening effect induced by increasing temperatures, the process of simulation cold-beating cause the grain shape of 1020 steel significant change and microstructure elongate significantly to form a fibrous tissue parallel to the direction of deformation, the higher strain rate, the more obvious grain refinement and the more hardening effect. Additionally, the change law of the work hardening rate is investigated, the relationship between dislocation density and strain, the relationship between work hardening rate and dislocation density is obtained. Results show that the change trend of the work hardening rate of 1020 steel is divided into two stages, the work hardening rate decreases dramatically in the first stage and slowly decreases in the second stage, finally tending toward zero. Dislocation density increases with increasing strain and strain rate, work hardening rate decreases with increasing dislocation density. The research results provide the basis for solving the problem of improving the surface quality and performance of workpieces under cold-beating formation of 1020 steel.

  5. Work hardening and mechanical equation of state in some metals in monotonic loading

    International Nuclear Information System (INIS)

    Wire, G.L.; Ellis, F.V.; Li, C.Y.

    The work hardening coefficients of Type 316 stainless steel, niobium, and 1100 aluminum alloy are measured in tensile tests. It is demonstrated experimentally that in the measured stress, plastic strain rate, and temperature range the work hardening coefficient depends only on stress and plastic strain rate. The significance of the experimental results is discussed in terms of the concept of the mechanical equation of state for plastic deformation. 13 figures

  6. Stage IV work-hardening related to disorientations in dislocation structures

    DEFF Research Database (Denmark)

    Pantleon, W.

    2004-01-01

    The effect of deformation-induced disorientations on the work-hardening of metals is modelled based on dislocation dynamics. Essentially, Kocks’ dislocation model describing stage III hardening is extended to stage IV by incorporation of excess dislocations related to the disorientations....... Disorientations evolving from purely statistical reasons — leading to a square root dependence of the average disorientation angle on strain — affect the initial work-hardening rate (and the saturation stress) of stage III only slightly. On the other hand, deterministic contributions to the development...... of disorientations, as differences in the activated slip systems across boundaries, cause a linear increase of the flow stress at large strains. Such a constant work-hardening rate is characteristic for stage IV....

  7. Study on the Influence of the Work Hardening Models Constitutive Parameters Identification in the Springback Prediction

    International Nuclear Information System (INIS)

    Oliveira, M.C.; Menezes, L. F.; Alves, J.L.; Chaparro, B.M.

    2005-01-01

    The main goal of this work is to determine the influence of the work hardening model in the numerical prediction of springback. This study will be performed according with the specifications of the first phase of the 'Benchmark 3' of the Numisheet'2005 Conference: the 'Channel Draw'. Several work hardening constitutive models are used in order to allow a better description of the different material mechanical behavior. Two are classical pure isotropic hardening models described by a power law (Swift) or a Voce type saturation equation. Those two models were also combined with a non-linear (Lemaitre and Chaboche) kinematic hardening rule. The final one is the Teodosiu microstructural hardening model. The study is performed for two commonly used steels of the automotive industry: mild (DC06) and dual phase (DP600) steels. The mechanical characterization, as well as the constitutive parameters identification of each work hardening models, was performed by LPMTM, based on an appropriate set of experimental data such as uniaxial tensile tests, monotonic and Bauschinger simple shear tests and orthogonal strain path tests, all at various orientations with respect to the rolling direction. All the simulations were carried out with the CEMUC's home code DD3IMP (contraction of 'Deep Drawing 3-D IMPlicit code')

  8. Design and implementation of a programming circuit in radiation-hardened FPGA

    International Nuclear Information System (INIS)

    Wu Lihua; Han Xiaowei; Zhao Yan; Liu Zhongli; Yu Fang; Chen, Stanley L.

    2011-01-01

    We present a novel programming circuit used in our radiation-hardened field programmable gate array (FPGA) chip. This circuit provides the ability to write user-defined configuration data into an FPGA and then read it back. The proposed circuit adopts the direct-access programming point scheme instead of the typical long token shift register chain. It not only saves area but also provides more flexible configuration operations. By configuring the proposed partial configuration control register, our smallest configuration section can be conveniently configured as a single data and a flexible partial configuration can be easily implemented. The hierarchical simulation scheme, optimization of the critical path and the elaborate layout plan make this circuit work well. Also, the radiation hardened by design programming point is introduced. This circuit has been implemented in a static random access memory (SRAM)-based FPGA fabricated by a 0.5 μm partial-depletion silicon-on-insulator CMOS process. The function test results of the fabricated chip indicate that this programming circuit successfully realizes the desired functions in the configuration and read-back. Moreover, the radiation test results indicate that the programming circuit has total dose tolerance of 1 x 10 5 rad(Si), dose rate survivability of 1.5 x 10 11 rad(Si)/s and neutron fluence immunity of 1 x 10 14 n/cm 2 .

  9. Design and implementation of a programming circuit in radiation-hardened FPGA

    Science.gov (United States)

    Lihua, Wu; Xiaowei, Han; Yan, Zhao; Zhongli, Liu; Fang, Yu; Chen, Stanley L.

    2011-08-01

    We present a novel programming circuit used in our radiation-hardened field programmable gate array (FPGA) chip. This circuit provides the ability to write user-defined configuration data into an FPGA and then read it back. The proposed circuit adopts the direct-access programming point scheme instead of the typical long token shift register chain. It not only saves area but also provides more flexible configuration operations. By configuring the proposed partial configuration control register, our smallest configuration section can be conveniently configured as a single data and a flexible partial configuration can be easily implemented. The hierarchical simulation scheme, optimization of the critical path and the elaborate layout plan make this circuit work well. Also, the radiation hardened by design programming point is introduced. This circuit has been implemented in a static random access memory (SRAM)-based FPGA fabricated by a 0.5 μm partial-depletion silicon-on-insulator CMOS process. The function test results of the fabricated chip indicate that this programming circuit successfully realizes the desired functions in the configuration and read-back. Moreover, the radiation test results indicate that the programming circuit has total dose tolerance of 1 × 105 rad(Si), dose rate survivability of 1.5 × 1011 rad(Si)/s and neutron fluence immunity of 1 × 1014 n/cm2.

  10. Using intervention mapping to deconstruct cognitive work hardening: a return-to-work intervention for people with depression.

    Science.gov (United States)

    Wisenthal, Adeena; Krupa, Terry

    2014-12-12

    Mental health related work disability leaves are increasing at alarming rates with depression emerging as the most common mental disorder in the workforce. Treatments are available to alleviate depressive symptoms and associated functional impacts; however, they are not specifically aimed at preparing people to return to work. Cognitive work hardening (CWH) is a novel intervention that addresses this gap in the health care system. This paper presents a theoretical analysis of the components and underlying mechanisms of CWH using Intervention Mapping (IM) as a tool to deconstruct its elements. The cognitive sequelae of depression and their relevance to return-to-work (RTW) are examined together with interpersonal skills and other work-related competencies that affect work ability. IM, a tool typically used to create programs, is used to deconstruct an existing program, namely CWH, into its component parts and link them to theories and models in the literature. CWH has been deconstructed into intervention elements which are linked to program performance objectives through underlying theoretical models. In this way, linkages are made between tools and materials of the intervention and the overall program objective of 'successful RTW for people with depression'. An empirical study of the efficacy of CWH is currently underway which should provide added insight and understanding into this intervention. The application of IM to CWH illustrates the theoretical underpinnings of the treatment intervention and assists with better understanding the linkage between intervention elements and intervention objective. Applying IM to deconstruct an existing program (rather than create a program) presents an alternate application of the IM tool which can have implications for other programs in terms of enhancing understanding, grounding in theoretical foundations, communicating program design, and establishing a basis for program evaluation and improvement.

  11. Disorientations and their role on the work-hardening in stage IV

    DEFF Research Database (Denmark)

    Pantleon, W.

    2005-01-01

    statistical reasons still lead to stage III behavior and a saturation of the ow stress, but deterministic contributions to the development of disorienta- tions, as dierences in activated slip systems across boundaries, cause a linear increase of the flow stress at large strains. Such a constant work......The eect of deformation-induced disorientations on work-hardening of metals is modelled by dislocation dynamics. By incorporating excess dislocations related to disori- entations, Kocks' dislocation model describing stage III hardening is extended to stage IV. Disorientations evolving from purely...

  12. Hardening of Fe-Cr-Mn steels cold plastic working

    International Nuclear Information System (INIS)

    Malinov, L.S.; Konop-Lyashko, V.I.; Nikoporets, N.M.

    1983-01-01

    The dependence is established between the level of proper-- ties obtained after cold plastic working and development of martensite transformations when loading in Fe-Cr-Mn steels containing 0.1-0.5% C, 13% Cr, 8-12% Mn, as well as in a number of complex alloyed steels. It is shown that the highest level of mechanical properties can be obtained after cold plastic working only in steels with definite austenite stability. Cold plastic working can both activize and stabilize austenite relatively to martensite formation during loading. The first thing is found when under the effect of preliminary cold working dislocation splitting takes place, as well as the formation of a small amount of E-phase and martensite. The second thing manifests itself when under the effect of cold working performed above Md (Md<20 deg C) cell dislocation structure is formed and dislocation pinning takes place

  13. Numerical implementation of a transverse-isotropic inelastic, work-hardening constitutive model

    International Nuclear Information System (INIS)

    Baladi, G.Y.

    1977-01-01

    During the past few decades the dramatic growth of computer technology has been paralleled by an increasing degree of complexity in material constitutive modeling. This paper documents the numerical implementation of one of these models, specifically a transverse-isotropic, inelastic, work-hardening constitutive model which is developed elsewhere by the author. (Auth.)

  14. Two-parametric model of metals hardening during cold working

    International Nuclear Information System (INIS)

    Khajkin, B.E.

    1985-01-01

    Mathematical models of cold working metal resistance σ depending on deformation degree have been analyzed. Advantage of two-parametric formula combining simplicity with satisfactory accuracy of experimental data approximation is noted. The formula is convenient when determining value σ, which is average with respect of deformation location, as average geometric value

  15. Numerical implementation of a transverse-isotropic inelastic, work-hardening constitutive model

    International Nuclear Information System (INIS)

    Baladi, G.Y.

    1977-01-01

    This paper documents the numerical implementation of a model, specifically a transverse-isotropic, inelastic, work-hardening constitutive model. A brief overview of the mathematical formulation of the model is presented to facilitate the understanding of its numerical implementation. The model is based on incremental flow theories for materials which have time- and temperature-independent properties and which are capable of undergoing small plastic as well as small elastic strain at each loading increment. In addition, the model is written in terms of 'pseudo' stress invariants so that the incremental anisotropic stress-strain relationship can be readily incorporated into existing finite-difference or finite-element computer codes. The isotropic version of the model is retrieved without any changes in the mathematical formulation or in the numerical implementation (algorithm) of the model. Various methods exist for incorporating inelastic constitutive models into computer programs. The method presented in this paper is appropriate for both finite-difference and finite-element codes, and is applicable for solving static as wall as dynamic problems. This method expresses the material constitutive properties as a matrix of coefficients, C (generalized tangent moduli), which relates incremental stresses to incremental strains. It possesses desirable convergence properties. In either finite-difference or finite-element applications the input quantities are the initial stress components, obtained at the end of the previous strain increment, and the new strain increments. The output quantities are the new values of the stress components

  16. Effect of cold work hardening on stress corrosion cracking of stainless steels in primary water of pressurized water reactors

    International Nuclear Information System (INIS)

    Raquet, O.; Herms, E.; Vaillant, F.; Couvant, T.; Boursier, J.M.

    2004-01-01

    A R and D program is carried out in CEA and EDF laboratories to investigate separately the effects of factors which could contribute to IASCC mechanism. In the framework of this study, the influence of cold work on SCC of ASSs in primary water is studied to supply additional knowledge concerning the contribution of radiation hardening on IASCC of ASSs. Solution annealed ASSs, essentially of type AISI 304(L) and AISI 316(L), are generally considered very resistant to SCC in nominal primary water. However, Constant Extension Rate Tests (CERTs), performed on cold pressed humped specimens in nominal primary water at 360 deg. C, reveal that these materials can exhibit a high SCC susceptibility: deepest cracks reach 1 mm (mean crack growth rate about 1 μm.h -1 ) and propagation is mainly intergranular for 304L and mainly transgranular for 316L. Indeed, work hardening in conjunction with high localized deformation can promote SCC. The influence of the nature of the cold work (shot peening, reaming, cold rolling, counter sinking, fatigue work hardening and tensile deformation) is investigated by means of screening CERTs performed with smooth specimens in 304L at 360 deg. C. For a given cold work hardening level, the susceptibility to crack initiation strongly depends on the cold working process, and no propagation is observed for a hardness level lower than 300 ±10 HV(0.49N). The propagation of cracks is observed only for dynamic loadings like CERT, traction/relaxation tests and crack growth rate tests performed with CT specimens under trapezoidal loading. Although crack initiation is observed for constant load and constant deformation tests, crack propagation do not seem to occur under these mechanical solicitations for 17000 hours of testing, even for hardness levels higher than 450 HV(0.49N). The mean crack growth rate increases when the hardness increases. An important R and D program is in progress to complement these results and to develop a SCC model for ASSs in

  17. Work-hardening stages and deformation mechanism maps during tensile deformation of commercially pure titanium

    DEFF Research Database (Denmark)

    Becker, Hanka; Pantleon, Wolfgang

    2013-01-01

    Commercially pure titanium was tensile tested at different strain rates between 2.2×10−4s−1 and 6.7×10−1s−1 to characterize the strain rate dependence of plastic deformation and the dominating deformation mechanisms. From true stress-true plastic strain curves, three distinct work-hardening stages...... are identified. The work-hardening rate decreases linearly with increasing flow stress for all three stages and the work-hardening rate is the controlling factor for the transition between the different stages and mechanisms. During the initial stage (at lowest stresses) plastic deformation is carried mainly...... by dislocation slip, in the following stage (for moderate stresses), an abundance of 64.6∘〈1¯010〉 twin boundaries form indicating the dominance of {112¯2}〈1¯1¯23〉 compression twinning. During the last stage before the onset of necking, additional 84.8∘〈112¯0〉 twin boundaries are detected caused by {101...

  18. A work-hardening rule for finite elastic-plastic deformation of metals at elevated temperatures

    International Nuclear Information System (INIS)

    Lee, L.H.N.; Horng, J.T.

    1975-01-01

    The paper is concerned with an extension of Prager-Ziegler's kinematic work-hardening rule for infinitesimal elastic-plastic deformation to a work-hardening rule for finite elastic-plastic deformation of a polycrystalline metal. It is shown that the finite work-hardening rule, which accounts for the Bauschinger and temperature effects within certain pressure and temperature ranges, satisfies certain invariant, continuity and thermodynamic requirements. A description of the kinematics of an elastic-plastic body is employed with reference to three separate configurations: initial, current and an intermediate configuration. The intermediate configuration is a conceptual, local configuration obtained by removing the stress and temperature changes in the neighborhood of an element. A rigid body rotation of the intermediate configuration is allowed. Piola-Kirchhoff stresses and Green deformation tensors referred to the initial and intermediate configurations are employed as stress and strain measures. The plastic deformation has been associated with the motion and production of dislocations. It has been observed that the motion of mobile dislocations usually occur in the narrow slip bands in each grain, leaving the basic lattice structure practically intact, so that the macroscopic elastic properties of the material are essentially independent of plastic deformation. Employing this fact and the thermodynamic laws, a simplified elastic stress-strain relationship of the plastically deformed material, which agrees with the results of Naghdi and Trapp, is obtained

  19. Application of the Single Hardening Model in the Finite Element Program ABAQUS

    DEFF Research Database (Denmark)

    Jakobsen, Kim Parsberg

    model, developed by Lade and Kim (Kim & Lade 1988, Lade & Kim 1988a, Lade & Kim 1988b) is implemented as a user defined material module, UMAT, in the commercial finite element program, ABAQUS. The advantages of the Single Hardening Model Iie in its ability to predict elastic and plastic displacements...

  20. Surface hardening using cw CO2 laser: laser heat treatment, modelation, and experimental work

    Science.gov (United States)

    Muniz, German; Alum, Jorge

    1996-02-01

    In the present work are given the results of the application of laser metal surface hardening techniques using a cw carbon dioxide laser as an energy source on steel 65 G. The laser heat treatment results are presented theoretically and experimentally. Continuous wave carbon dioxide laser of 0.6, 0.3, and 0.4 kW were used. A physical model for the descriptions of the thermophysical laser metal interactions process is given and a numerical algorithm is used to solve this problem by means of the LHT code. The results are compared with the corresponding experimental ones and a very good agreement is observed. The LHT code is able to do predictions of transformation hardening by laser heating. These results will be completed with other ones concerning laser alloying and cladding presented in a second paper.

  1. A general shakedown theorem for elastic/plastic bodies with work hardening

    International Nuclear Information System (INIS)

    Ponter, A.R.S.

    1975-01-01

    In recent years the design of metallic structures under variable loading has been assisted by the application of Melan's lower bound theorem for the shakedown on an elastic/perfectly plastic structure. The design codes for both portal frames and pressure vessels have taken account of such calculations. The theory of shakedown suffers from two defects, geometry changes are ignored and the material behaviour is described by a perfectly plastic constitutive relationship which includes neither work hardening nor the Bauschinger effect. This paper is concerned with the latter problem. A very general lower bound shakedown theorem is derived for an arbitrary time-independent material in terms of functional properties of the constitutive relationship. The theorem is then applied to perfect, isotropic and kinematic hardening plasticity. (Auth.)

  2. Work hardening characteristics of gamma-ray irradiated Al-5356 alloy

    International Nuclear Information System (INIS)

    Saad, G.; Fayek, S.A.; Fawzy, A.; Soliman, H.N.; Nassr, E.

    2014-01-01

    Effects of γ-irradiation and deformation temperatures on the hardening behavior of Al-5356 alloy have been investigated by means of stress–strain measurements. Wire samples irradiated with different doses (ranging from 500 to 2000 kGy) were strained at different deformation temperatures T w (ranging from 303 to 523 K) and a constant strain rate of 1.5×10 −3 s −1 . The effect of γ-irradiation on the work-hardening parameters (WHP): yield stress σ y , fracture stress σ f , total strain ε T and work-hardening coefficient χ p of the given alloy was studied at the applied deformation temperature range. The obtained results showed that γ-irradiation exhibited an increase in the WHP of the given alloy while the increase in its deformation temperature showed a reverse effect. The mean activation energy of the deformation process was calculated using an Arrhenius-type relation, and was found to be ∼80 kJ/mole, which is close to that of grain boundary diffusion in aluminum alloys

  3. Age hardening of cold-worked Zr-2.5 wt% Nb pressure tube alloy

    International Nuclear Information System (INIS)

    Kishore, R.; Singh, R.N.; Dey, G.K.; Sinha, T.K.

    1992-01-01

    Specimens for hardness and tensile tests, machined from a cold-worked zirconium-2.5% niobium pressure tube, with their axes parallel to longitudinal and transverse directions, were aged for 1 hr. at 300-500 C. The age hardening behaviour was monitored by mechanical tests, electron-microscopy and x-ray diffraction. In addition a few studies were carried on longitudinal tension specimens subjected to prolonged ageing (100-1000 hrs) at 300 C. It was observed that the short-term (1 hour) thermal ageing of this material at 300-400 C caused an increase in both strength and hardness without affecting ductility. It appears that the observed age-hardening is due to precipitation hardening by a niobium-rich phase and softening by recovery of cold-work and that the phenomenon is influenced by crystallographic texture. Further it was noted that a prolonged ageing at 300 C upto 1000 hrs, did not cause any appreciable changes in strength and ductility of the material compared to those obtained by 1 hour ageing at the same temperature. (author). 11 refs., 3 figs., 2 tabs

  4. A Study of Tensile Flow and Work-Hardening Behavior of Alloy 617

    Science.gov (United States)

    Singh, Aditya Narayan; Moitra, A.; Bhaskar, Pragna; Dasgupta, Arup; Sasikala, G.; Bhaduri, A. K.

    2018-04-01

    The simple power relationship σ = Κɛ p n satisfactorily expresses the tensile flow behavior of many metals and alloys in their uniform plastic strain regime. However, many FCC materials with low stacking fault energy have opposed such power law relationship. Alloy 617, an age-hardenable Ni-based superalloy is also observed not to obey the simple power law relationship neither in its solution-treated nor in its aged conditions. Various flow relationships were used to obtain the best fit for the tensile data, and different relationships were identified for the different aged conditions. The work-hardening rate (θ) demonstrates three distinct regions for all aged conditions, and there is an obvious change in the trend of θ versus σ. In the initial portion, θ decreases rapidly followed by a gradual increase in the second stage and again a decrease in its third stage is perceived in the Alloy 617. These three-stage characteristics are attributed to a commonly known precipitate, γ': Ni3(Ti, Al) which evolves during aging treatment and well recognized under transmission electron microscopy (TEM) observation. TEM results also reveal a slight degree of coarsening in γ' over aging. The tensile flow and the work-hardening behavior are well correlated with other microstructural evolution during the aging treatments.

  5. Stress-relaxation tests in the work-hardening regime of tungsten single crystals below 300 K

    International Nuclear Information System (INIS)

    Brunner, D.

    2008-01-01

    The influence of work hardening on the results of stress-relaxation tests was studied for highly pure tungsten single crystals isothermally deformed at four temperatures of 274, 241, 131, and 78 K. A method accounting for strong work hardening on the determination of the strain-rate sensitivity from stress-relaxation tests is introduced by establishing special diagrams of SR tests denoted as YX diagrams

  6. Numerical implementation of a transverse-isotropic inelastic, work-hardening constitutive model

    International Nuclear Information System (INIS)

    Baladi, G.Y.

    1978-01-01

    The numerical implementation of a transverse-isotropic inelastic, work-hardening plastic constitutive model is documented. A brief review of the model is presented first to facilitate the understanding of its numerical implementation. This model is formulated in terms of 'pseudo' stress invariants, so that the incremental stress-strain relationship can be readily incorporated into existing finite-difference or infinite-element computer codes. The anisotropic model reduces to its isotropic counterpart without any changes in the mathematical formulation or in the numerical implementation (algorithm) of the model. A typical example of the model and its behavior in uniaxial strain and triaxial compression is presented. (Auth.)

  7. Kinetic characterization and of recrystallization of the aluminum alloy 6063 after S work hardening treatment

    International Nuclear Information System (INIS)

    Esposito, Iara Maria

    2006-01-01

    The aluminum 6063 alloy possesses a great industrial interest, presenting characteristics that justify its frequent use, when compared to the other aluminum alloys: the precipitation hardening and high cold work capacity. These alloys present high ductility, that allows their use in operations with high deformation degrees, as the cold work. The objective of this work is to show comparative analysis of the hardness Vickers of the commercial aluminum 6063 alloy, after cold work with different area reduction degree and thermal treatment. Considering the frequent utilization aluminium 6063 alloy, this work studies the characterization and recrystallization of this alloy, after the plastic deformation in different area reduction degrees, thermal treatment and convenient treatment times - Thermo mechanic Treatments. (author)

  8. In-situ neutron diffraction study on work-hardening behavior in a ferrite-martensite dual phase steel

    OpenAIRE

    Morooka, Satoshi; Sato, Naoko; Ojima, Mayumi; Harjo, Stefanus; Adachi, Yoshitaka; Tomota, Yo; Umezawa, Osamu

    2011-01-01

    Strength and work-hardening in steels have been discussed from the viewpoint of heterogeneous deformation. In-situ neutron diffraction techniques made clear that the misfit strains between grains accompanied with the grain-scaled internal stress (intergranular stress). In the dual phase steel, the intergranular stress was superposed on phase stress. Both long-range internal stress and short-range one like forest dislocation hardening may cause the resistance for dislocation motion in the steels.

  9. Radiation Effects and Component Hardening testing program at the Oak Ridge National Laboratory

    International Nuclear Information System (INIS)

    Draper, J.V.; Weil, B.S.; Chesser, J.B.

    1993-01-01

    This paper describes Phase II of the Radiation Effects and Component Hardening (REACH) testing program, performed as part of the joint collaborative agreement between the United States Department of Energy (USDOE) and the Power Reactor and Nuclear Fuel Development Corporation (PNC) of Japan, Components and materials were submitted to 10 5 R/hr gamma radiation fields for 10,000 hr, producing accumulated doses of 10 9 R; most performed as expected

  10. Defects produced by the work hardening of magnesium and cadmium at low temperatures

    International Nuclear Information System (INIS)

    Simon, Jean-Paul; Delaplace, Jean

    1971-07-01

    Simultaneous measurements of the mechanical properties and the electrical resistivity of cadmium and magnesium samples which have been work hardened at 77 deg. K enabled the defects produced and the recovery occurring during an annealing process, to be studied. The electrical resistivity measured at 77 deg. K increased linearly with the deformation for the degrees of work hardening considered (less than 7 per cent for Cd and less than 4 per cent for Mg). Three main stages occurred in the recovery of Cd: stage A between 77 deg. K and 180 deg. K due to annealing of point defects, stage B between 180 deg. K and 240 deg. K due to the rearrangement of the dislocations and stage C above 240 deg. K due to recrystallization. Measurements of electrical resistance were made when the sample was under stress and when the stress was removed. The resistivity of both Cd and Mg changed during the removal of the load. This phenomenon is ascribed to the shortening of the dislocation segments which are bowed under stress and straighten when the stress is removed. The orders of magnitude of the dislocation density and the loop lengths obtained from this model, are reasonable [fr

  11. Tensile flow and work-hardening behavior of a Ti-modified austenitic stainless steel

    International Nuclear Information System (INIS)

    Sivaprasad, P.V.; Venugopal, S.; Venkadesan, S.

    1997-01-01

    The flow-stress data of a 15Cr-15Ni-2.2Mo-Ti modified austenitic stainless steel in the temperature range 300 to 1,023 K was analyzed in terms of Ludwigson and Voce equations. The parameters of these equations were critically examined with respect to the effect of Ti/C ratio and test temperature. It was found that the Ludwigson equation described the flow behavior adequately up to the test temperature of 923 K, whereas the Voce equation could be employed in the full temperature range. The peaks/plateaus observed in the variation of these parameters as a function of temperature in the intermediate temperature range have been identified as one of the manifestations of dynamic strain aging (DSA). Also, the variation of these parameters with temperature clearly could bring out the different domains of DSA observed in this alloy. The work-hardening analysis of the flow-stress data revealed that in the DSA regime, the onset of stage III hardening is athermal

  12. A general shakedown theorem for elastic/plastic bodies with work hardening

    International Nuclear Information System (INIS)

    Ponter, A.R.S.

    1975-01-01

    In recent years the design of metallic structures under variable loading has been assisted by the application of Melan's lower bound theorem for the shakedown of an elastic/perfectly plastic structure. The design codes for both portal frames and pressure vessels have taken account of such calculations. The theory of shakedown suffers from two defects, geometry changes are ignored and the material behavior is described by a perfectly plastic constitutive relationship which includes neither work hardening nor the Bauschinger effect. This paper is concerned with the latter problem. A very general lower bound shakedown theorem for an arbitrary time-independent material in terms of functional properties of the constitutive relationship is derived. The theorem is then applied to perfect, isotropic and kinematic hardening plasticity. It is shown that the result for all three constitutive relationships may be related to each other through certain extremal stress histories. As well as providing a sufficient condition for shakedown, the theory also provides bounds of the deflection of the structure in the process of reaching the shakedown state. The bounds are discussed and derived for two simple beam problems. Both static and dynamic problems are considered. The theory derived in this paper demonstrates that shakedown analysis may be extended to a wide range of material behavior without increasing the complexity of the resulting calculation

  13. Effects of thermomechanical processing on microstructure and properties of bainitic work hardening steel

    Energy Technology Data Exchange (ETDEWEB)

    Cao, Jie, E-mail: caojie910@ahut.edu.cn [School of Metallurgical Engineering, Anhui University of Technology, Ma’anshan 243002 (China); Yan, Jun; Zhang, Jing [School of Metallurgical Engineering, Anhui University of Technology, Ma’anshan 243002 (China); Yu, Tongren [Technology Center, Maanshan Iron & Steel Company Limited, Ma’anshan 243000 (China)

    2015-07-15

    The thermomechanical processing (TMP) of a bainitic work hardening steel was carried out on a Gleeble3500 simulator. The microstructure of processed specimens was investigated by means of optical and electron microscopy, and tensile tests were performed in a ZwickRoell tensile tester. The deformation temperatures of austenite varied from 800 °C to 900 °C. The cooling methods include single rate cooling method and two-stage cooling method. The two-stage cooling method includes fast cooling rates ranging from 4 °C/s to 12 °C/s and slow cooling rates ranging from 1 °C/s to 2 °C/s. It is shown that, within the range of parameters tested, the obtained microstructures are granular bainite, the tensile strength of the steel can be adjusted from 897.8 MPa to 1083.2 MPa, and good plasticity can be obtained at different strength levels.

  14. Work hardening characteristics in Al base alloys with 12.6 and 45 wt.% Zn

    International Nuclear Information System (INIS)

    Abd El-Salam, F.; Mostafa, M.M.; Wahab, L.A.; Mostafa, M.T.; Abd El-Aziz, Sh.M.

    2008-01-01

    The stress-strain curves were obtained for Al-Zn alloys of 12.6 wt.% Zn (alloy I) and 45 wt.% Zn (alloy II) with elements of purity (99.99). The monotonic shift of these curves towards lower flow stress and higher ductility was interrupted at the transformation temperatures 483 K (alloy I) and both 543, 603 K (alloy II). By increasing deformation temperature, Young's modulus, Y, yield and fracture stresses, σ y and σ f , respectively, fracture time, t f , the coefficient of parabolic work hardening, χ, decreased while fracture strain, ε f , and dislocation slip distance, L, increased. From the obtained X-rays diffraction patterns the lattice strain, ε, crystallite size, η, and dislocation density, ρ, were obtained at different deformation temperatures around transformation

  15. The variation of work hardening characteristics of Al-5 wt% Mg alloy during phase transition

    International Nuclear Information System (INIS)

    Mahmoud, M.A.; Sobhy, M.; Abd El-Rehim, A.F.; Abdel Rahman, R.M.

    2010-01-01

    The aim of this study is to investigate the effect of aging conditions on the stress-strain behavior along with microstructure changes of the Al-5 wt% Mg alloy. Following solid solution treatment and aging of specimens at temperatures ranging from 373 to 573 K for various aging times (1/4 to 4 h), stress-strain tests were performed at different testing temperatures (313-343 K). The work hardening parameters (σ y , σ f , χ p and Y) were found to decrease continuously with pre-aging times at all aging and testing temperatures, where the softening parameters (ε f and L) oppose this behavior. The variation in stress-strain parameters with increasing aging temperatures and aging times was explained on the basis of structural transformations taking place in the Al-Mg alloy. A precipitate-dislocation intersections mechanism was assumed as the rate-controlling mechanism for alloy.

  16. Relation between superficial work hardening and SCC of an austenitic stainless steel Z3CND17-12 (AISI 316L)

    International Nuclear Information System (INIS)

    Bouzina, A.; Braham, C.; Ledion, J.

    1998-01-01

    A superficial strain hardening always leads to residual stresses. Loading during service can completely modify these stresses in a component. Without questioning the fact that compressive stresses are favourable for stress corrosion resistance, the authors show how an elastoplastic deformation on a pre-stressed material, by machining or shot peening, can be more harmful than on a non work hardened or uniformly work hardened material. (authors)

  17. Work status and health-related quality of life following multimodal work hardening: a cluster randomised trial.

    Science.gov (United States)

    Bethge, M; Herbold, D; Trowitzsch, L; Jacobi, C

    2011-01-01

    Systematic reviews have confirmed the effectiveness of work-related rehabilitation with significant cognitive-behavioural components for patients with musculoskeletal disorders (MSDs). In Germany, however, work-related rehabilitation focuses mainly on functional capacity training and less on psychosocial work demands. To evaluate the efficacy of multimodal work hardening (MWH) with a cognitive-behavioural approach. Patients with MSDs resulting in severe restriction of work ability were randomly assigned to treatment by either MWH or conventional musculoskeletal rehabilitation (controls). The primary outcome was work status. The work status at 6 months of follow-up was defined as positive if the patient was working and had ≤ 6 weeks of sick leave, and that at 12 months was defined as positive if the patient was working and had ≤12 weeks of sick leave. Follow-up data were collected by postal questionnaires. 236 patients consented to participate. Follow-up data were obtained from 169 (71.6%) participants at 6 months and 146 (61.9%) participants at 12 months. At 6 months, participants in the MWH group had a 2.4 times higher chance of a positive work status than the controls (OR=2.363; 95% CI: 1.266 to 4.410; p=0.007). At 12 months, the chances of a positive work status were still higher, but this difference was not statistically significant (OR=1.914; 95% CI: 0.849 to 4.317; p=0.118). Significance of the interaction term of treatment and time indicated more favourable outcomes for depression and anxiety, mental and physical health-related quality of life, and pain management in the MWH group. MWH improves health-related quality of life and is able to enhance the mid-term chances of work-life participation.

  18. Evolution of stacking fault tetrahedral and work hardening effect in copper single crystals

    Science.gov (United States)

    Liu, Hai Tao; Zhu, Xiu Fu; Sun, Ya Zhou; Xie, Wen Kun

    2017-11-01

    Stacking fault tetrahedral (SFT), generated in machining of copper single crystal as one type of subsurface defects, has significant influence on the performance of workpiece. In this study, molecular dynamics (MD) simulation is used to investigate the evolution of stacking fault tetrahedral in nano-cutting of copper single crystal. The result shows that SFT is nucleated at the intersection of differently oriented stacking fault (SF) planes and SFT evolves from the preform only containing incomplete surfaces into a solid defect. The evolution of SFT contains several stress fluctuations until the complete formation. Nano-indentation simulation is then employed on the machined workpiece from nano-cutting, through which the interaction between SFT and later-formed dislocations in subsurface is studied. In the meanwhile, force-depth curves obtained from nano-indentation on pristine and machined workpieces are compared to analyze the mechanical properties. By simulation of nano-cutting and nano-indentation, it is verified that SFT is a reason of the work hardening effect.

  19. Abandoned works program

    International Nuclear Information System (INIS)

    Arnott, A.

    2007-01-01

    Thousands of improperly abandoned or decommissioned oil and gas wells are threatening the purity of Ontario's source water. This presentation discussed an abandoned works program developed by the Ontario Ministry of Natural Resources. The abandoned works program was established in 2005 in order to plug old oil and gas wells. The program was designed to create a list of abandoned wells, develop a coherent policy, and formulate procurement and contracting protocols. Abandoned wells are defined as wells drilled prior to 1963 with no operator other than the current landowner. There are currently over 200 prioritized wells on the list. Twenty-six contracts have been issued for a total of 33 wells, and 19 wells have been plugged since the program's field operations began in 2006. However, the program is often challenged by the difficulties associated with determining where the wells are located. Many of the wells have been cut off and buried, and access is often dependent on weather conditions and road restrictions. There is also a shortage of contractors who have experience working with older wells. It was concluded that the program will expand by obtaining further funding and modifying its qualification criteria. tabs., figs

  20. Tensile stress–strain and work hardening behaviour of P9 steel for wrapper application in sodium cooled fast reactors

    International Nuclear Information System (INIS)

    Christopher, J.; Choudhary, B.K.; Isaac Samuel, E.; Mathew, M.D.; Jayakumar, T.

    2012-01-01

    Highlights: ► σ–ε behaviour has been adequately described by Ludwigson and Hollomon equations. ► Instantaneous work hardening rate (θ) exhibited two-stage behaviour. ► σ–ε, flow parameters, θ and θσ vs.σ exhibited three distinct temperature regimes. ► Influence of dynamic strain ageing at intermediate temperatures has been identified. ► Dominance of dynamic recovery at high temperatures was demonstrated. - Abstract: Tensile flow behaviour of P9 steel with different silicon content has been examined in the framework of Hollomon, Ludwik, Swift, Ludwigson and Voce relationships for a wide temperature range (300–873 K) at a strain rate of 1.3 × 10 −3 s −1 . Ludwigson equation described true stress (σ)–true plastic strain (ε) data most accurately in the range 300–723 K. At high temperatures (773–873 K), Ludwigson equation reduces to Hollomon equation. The variations of instantaneous work hardening rate (θ = dσ/dε) and θσ with stress indicated two-stage work hardening behaviour. True stress–true plastic strain, flow parameters, θ vs. σ and θσ vs. σ with respect to temperature exhibited three distinct temperature regimes and displayed anomalous behaviour due to dynamic strain ageing at intermediate temperatures. Rapid decrease in flow stress and flow parameters, and rapid shift in θ–σ and θσ–σ towards lower stresses with increase in temperature indicated dominance of dynamic recovery at high temperatures.

  1. Design cost scoping studies. Nevada Test Site Terminal Waste Storage Program, Subtask 1.3: facility hardening studies

    International Nuclear Information System (INIS)

    Yanev, P.I.; Owen, G.N.

    1978-04-01

    As part of a program being conducted by the U.S. Department of Energy, Nevada Operations Office, to determine the feasibility of establishing a terminal waste storage repository at the Nevada Test Site, URS/John A. Blume and Associates, Engineers, made approximate determinations of the additional costs required to provide protection of structures against seismic forces. A preliminary estimate is presented of the added costs required to harden the surface structures, underground tunnels and storage rooms, and vertical shafts of the repository against ground motion caused by earthquakes and underground nuclear explosions (UNEs). The conceptual design of all of the structures was adapted from proposed bedded-salt waste-isolation repositories. Added costs for hardening were calculated for repositories in three candidate geological materials (Eleana argillite, Climax Stock granite, and Jackass Flats tuff) for several assumed peak ground accelerations caused by earthquakes (0.3g, 0.5g, and 0.7g) and by UNEs (0.5g, 0.7g, and 1.0g). Hardening procedures to protect the tunnels, storage rooms, and shafts against incremental seismic loadings were developed from (1) qualitative considerations of analytically determined seismic stresses and (2) engineering evaluations of the dynamic response of the rock mass and the tunnel support systems. The added costs for seismic hardening of the surface structures were found to be less than 1% of the estimated construction cost of the surface structures. For the underground structures, essentially no hardening was required for peak ground accelerations up to 0.3g; however, added costs became significant at 0.5g, with a possible increase in structural costs for the underground facilities of as much as 35% at 1.0g

  2. Work Hardening, Dislocation Structure, and Load Partitioning in Lath Martensite Determined by In Situ Neutron Diffraction Line Profile Analysis

    Science.gov (United States)

    Harjo, Stefanus; Kawasaki, Takuro; Tomota, Yo; Gong, Wu; Aizawa, Kazuya; Tichy, Geza; Shi, Zengmin; Ungár, Tamas

    2017-09-01

    A lath martensite steel containing 0.22 mass pct carbon was analyzed in situ during tensile deformation by high-resolution time-of-flight neutron diffraction to clarify the large work-hardening behavior at the beginning of plastic deformation. The diffraction peaks in plastically deformed states exhibit asymmetries as the reflection of redistributions of the stress and dislocation densities/arrangements in two lath packets: soft packet, where the dislocation glides are favorable, and hard packet, where they are unfavorable. The dislocation density was as high as 1015 m-2 in the as-heat-treated state. During tensile straining, the load and dislocation density became different between the two lath packets. The dislocation character and arrangement varied in the hard packet but hardly changed in the soft packet. In the hard packet, dislocations that were mainly screw-type in the as-heat-treated state became primarily edge-type and rearranged towards a dipole character related to constructing cell walls. The hard packet played an important role in the work hardening in martensite, which could be understood by considering the increase in dislocation density along with the change in dislocation arrangement.

  3. Tensile stress-strain and work hardening behaviour of P9 steel for wrapper application in sodium cooled fast reactors

    Science.gov (United States)

    Christopher, J.; Choudhary, B. K.; Isaac Samuel, E.; Mathew, M. D.; Jayakumar, T.

    2012-01-01

    Tensile flow behaviour of P9 steel with different silicon content has been examined in the framework of Hollomon, Ludwik, Swift, Ludwigson and Voce relationships for a wide temperature range (300-873 K) at a strain rate of 1.3 × 10 -3 s -1. Ludwigson equation described true stress ( σ)-true plastic strain ( ɛ) data most accurately in the range 300-723 K. At high temperatures (773-873 K), Ludwigson equation reduces to Hollomon equation. The variations of instantaneous work hardening rate ( θ = dσ/ dɛ) and θσ with stress indicated two-stage work hardening behaviour. True stress-true plastic strain, flow parameters, θ vs. σ and θσ vs. σ with respect to temperature exhibited three distinct temperature regimes and displayed anomalous behaviour due to dynamic strain ageing at intermediate temperatures. Rapid decrease in flow stress and flow parameters, and rapid shift in θ- σ and θσ- σ towards lower stresses with increase in temperature indicated dominance of dynamic recovery at high temperatures.

  4. A constitutive model accounting for strain ageing effects on work-hardening. Application to a C-Mn steel

    Science.gov (United States)

    Ren, Sicong; Mazière, Matthieu; Forest, Samuel; Morgeneyer, Thilo F.; Rousselier, Gilles

    2017-12-01

    One of the most successful models for describing the Portevin-Le Chatelier effect in engineering applications is the Kubin-Estrin-McCormick model (KEMC). In the present work, the influence of dynamic strain ageing on dynamic recovery due to dislocation annihilation is introduced in order to improve the KEMC model. This modification accounts for additional strain hardening rate due to limited dislocation annihilation by the diffusion of solute atoms and dislocation pinning at low strain rate and/or high temperature. The parameters associated with this novel formulation are identified based on tensile tests for a C-Mn steel at seven temperatures ranging from 20 °C to 350 °C. The validity of the model and the improvement compared to existing models are tested using 2D and 3D finite element simulations of the Portevin-Le Chatelier effect in tension.

  5. Practical aspects of systems hardening

    International Nuclear Information System (INIS)

    Shepherd, W.J.

    1989-01-01

    Applications of hardening technology in a practical system require a balance between the factors governing affordability, producibility, and survivability of the finished design. Without careful consideration of the top-level system operating constraints, a design engineer may find himself with a survivable but overweight, unproductive, expensive design. This paper explores some lessons learned in applying hardening techniques to several laser communications programs and is intended as an introductory guide to novice designers faced with the task of hardening a space system

  6. “Not a Vacation, But a Hardening Process”: The Self-Empowerment Work of Therapeutic Craft in Nova Scotia

    Directory of Open Access Journals (Sweden)

    Erin Morton

    2014-10-01

    Full Text Available This article will examine the development of a state-sponsored therapeutic craft regime in Nova Scotia in the early to mid-twentieth century. Built on the notion that postwar residents needed "work therapy - not a vacation, but a hardening process" (Black n.d. a: 3 - therapeutic craft emerged in Nova Scotia through a complex combination of the individualization of work habits, the desire to construct an antimodern regional identity around handwork, and the notion that both infirm patients and the province as a whole could be healed from economic stagnation through craft. Key to the success of Nova Scotia's therapeutic craft regime was occupational therapist Mary E. Black's career as director of the provincial government's Handicrafts and Home Industries Division from 1943 to 1955. Black's healthcare training led her to seek out therapeutic possibilities in everyday work activities, not to mention a therapeutic solution to what she called "the atti-tude of most Nova Scotians"[:] defeatism" (Black 1949: 46. Her ability to turn seemingly disparate things - such as Scandinavian design, the ordered work of occupational rehabilitation, and a phenomenological focus on what she called “in-dividualistic existence” (Black n.d. b: 2 - into a unified therapeutic solution demonstrates that the contemporary rise of therapeutic culture under the increased individualism of the neoliberal era has an established historical root in the postwar period that remains important to understand.

  7. Relationship between 0.2% proof stress and Vickers hardness of work-hardened low carbon austenitic stainless steel, 316SS

    International Nuclear Information System (INIS)

    Matsuoka, Saburo

    2004-01-01

    Stress corrosion cracking (SCC) occurs in shrouds and piping made of low carbon austenitic stainless steels at nuclear power plants. A work-hardened layer is considered to be one of the probable causes for this occurrence. The maximum Vickers hardness measured at the work-hardened layer is 400 HV. It is important to determine the yield strength and tensile strength of the work-hardened layer in the investigation on the causes of SCC. However, the tensile specimen cannot be obtained since the thickness of the work-hardened layer is as mall as several hundred μm, therefore, it is useful if we can estimate these strengths from its Vickers hardness. Consequently, we investigated the relationships between Vickers hardness versus yield strength and tensile strength using the results obtained on various steels in a series of Fatigue Data Sheets published by the National Institute for Materials Science and results newly obtained on a parent material and rolled materials (reduction of area: 10 - 50%, maximum hardness: 350 HV) for a low carbon stainless steel. The results showed that (1) the relationship between the 0.2% proof stress and the Vickers hardness can be described by a single straight line regardless of strength, structure, and rolling ratio, however, (2) the tensile strength is not correlated with the Vickers hardness, and the austenitic stainless steel in particular shows characteristics different from those of other steels. (author)

  8. NWMO transportation technical work program

    International Nuclear Information System (INIS)

    Hatton, C.

    2015-01-01

    This paper describes technical work program for the transportation nuclear waste by the Nuclear Waste Management Organization (NWMO). Transportation work program involves risk assessment which under normal conditions involves dose assessment to the worker and the public as well as consideration of transportation system routing and operations. It also involves possible accident scenarios using forensic modelling and probability analysis.

  9. NWMO transportation technical work program

    Energy Technology Data Exchange (ETDEWEB)

    Hatton, C. [Nuclear Waste Management Organization, Toronto, ON (Canada)

    2015-07-01

    This paper describes technical work program for the transportation nuclear waste by the Nuclear Waste Management Organization (NWMO). Transportation work program involves risk assessment which under normal conditions involves dose assessment to the worker and the public as well as consideration of transportation system routing and operations. It also involves possible accident scenarios using forensic modelling and probability analysis.

  10. Effect of particle morphology and microstructure on strength, work-hardening and ductility behaviour of ODS-(7-13)Cr steels

    International Nuclear Information System (INIS)

    Preininger, D.

    2004-01-01

    The effect of particle morphology and grain refinement to the nanometer scale on strength, work-hardening and tensile ductility of reduced activation ODS-(7-13)Cr steels has been modelled with a dependence on deformation temperature (T=RT-700 deg. C) and a superimposed irradiation hardening. The Orowan model predictions describe as the upper limit the observed particle strengthening of various ODS-(7-13)Cr-(≤0.5 wt% yttria) steels. An optimum particle size d p * congruent with 7-22 nm (f v =0.004-0.05) and strength, together with a lower limiting ultra-fine grain size d K,c ≥90 nm result in maximum uniform ductility increase by grain refinement and dispersion hardening (DIGD). Optimum size d p * increases with increasing particle volume fraction f v and deformation temperature and decreases with irradiation hardening and grain refinement. The region of DIGD is limited to achieve a critical strength σ L corresponding to a critical particle volume fraction f v,c and grain size d K,c , above which uniform strain becomes limited by the strong drop of fracture strain. Grain refinement and irradiation hardening decrease σ L , f v,c and increase d K,c . In accordance with experimental results of ODS-Eurofer, nominal uniform strain increases with increasing f v by about ε u,n =B e +A e lnf v , most strongly around 300 deg. C, but weakly at the 600 deg. C minimum. The strong ductility increase above 600 deg. C results from a reduction of dislocation annihilation and structural recovery of strength. At T K,c for lower f v toward a saturation value which increases with increasing ratio of shear modulus to Hall-Petch constant. The enhanced uniform ductility at T≥300 deg. C is otherwise strongly decreased by grain refinement, more pronounced at lower f v and for strengths above σ L

  11. Laser Cladding of CPM Tool Steels on Hardened H13 Hot-Work Steel for Low-Cost High-Performance Automotive Tooling

    Science.gov (United States)

    Chen, J.; Xue, L.

    2012-06-01

    This paper summarizes our research on laser cladding of high-vanadium CPM® tool steels (3V, 9V, and 15V) onto the surfaces of low-cost hardened H13 hot-work tool steel to substantially enhance resistance against abrasive wear. The results provide great potential for fabricating high-performance automotive tooling (including molds and dies) at affordable cost. The microstructure and hardness development of the laser-clad tool steels so obtained are presented as well.

  12. The influence of stacking fault energy on the mechanical behavior of Cu and Cu-Al alloys: Deformation twinning, work hardening, and dynamic recovery

    Science.gov (United States)

    Rohatgi, Aashish; Vecchio, Kenneth S.; Gray, George T.

    2001-01-01

    The role of stacking fault energy (SFE) in deformation twinning and work hardening was systematically studied in Cu (SFE ˜78 ergs/cm2) and a series of Cu-Al solid-solution alloys (0.2, 2, 4, and 6 wt pct Al with SFE ˜75, 25, 13, and 6 ergs/cm2, respectively). The materials were deformed under quasi-static compression and at strain rates of ˜1000/s in a Split-Hopkinson pressure bar (SHPB). The quasi-static flow curves of annealed 0.2 and 2 wt pct Al alloys were found to be representative of solid-solution strengthening and well described by the Hall-Petch relation. The quasi-static flow curves of annealed 4 and 6 wt pct Al alloys showed additional strengthening at strains greater than 0.10. This additional strengthening was attributed to deformation twins and the presence of twins was confirmed by optical microscopy. The strengthening contribution of deformation twins was incorporated in a modified Hall-Petch equation (using intertwin spacing as the “effective” grain size), and the calculated strength was in agreement with the observed quasi-static flow stresses. While the work-hardening rate of the low SFE Cu-Al alloys was found to be independent of the strain rate, the work-hardening rate of Cu and the high SFE Cu-Al alloys (low Al content) increased with increasing strain rate. The different trends in the dependence of work-hardening rate on strain rate was attributed to the difference in the ease of cross-slip (and, hence, the ease of dynamic recovery) in Cu and Cu-Al alloys.

  13. A Combined Precipitation, Yield Stress, and Work Hardening Model for Al-Mg-Si Alloys Incorporating the Effects of Strain Rate and Temperature

    Science.gov (United States)

    Myhr, Ole Runar; Hopperstad, Odd Sture; Børvik, Tore

    2018-05-01

    In this study, a combined precipitation, yield strength, and work hardening model for Al-Mg-Si alloys known as NaMo has been further developed to include the effects of strain rate and temperature on the resulting stress-strain behavior. The extension of the model is based on a comprehensive experimental database, where thermomechanical data for three different Al-Mg-Si alloys are available. In the tests, the temperature was varied between 20 °C and 350 °C with strain rates ranging from 10-6 to 750 s-1 using ordinary tension tests for low strain rates and a split-Hopkinson tension bar system for high strain rates, respectively. This large span in temperatures and strain rates covers a broad range of industrial relevant problems from creep to impact loading. Based on the experimental data, a procedure for calibrating the different physical parameters of the model has been developed, starting with the simplest case of a stable precipitate structure and small plastic strains, from which basic kinetic data for obstacle limited dislocation glide were extracted. For larger strains, when work hardening becomes significant, the dynamic recovery was linked to the Zener-Hollomon parameter, again using a stable precipitate structure as a basis for calibration. Finally, the complex situation of concurrent work hardening and dynamic evolution of the precipitate structure was analyzed using a stepwise numerical solution algorithm where parameters representing the instantaneous state of the structure were used to calculate the corresponding instantaneous yield strength and work hardening rate. The model was demonstrated to exhibit a high degree of predictive power as documented by a good agreement between predictions and measurements, and it is deemed well suited for simulations of thermomechanical processing of Al-Mg-Si alloys where plastic deformation is carried out at various strain rates and temperatures.

  14. Modelling flow and work hardening behaviour of cold worked Zr–2.5Nb pressure tube material in the temperature range of 30–600 oC

    International Nuclear Information System (INIS)

    Dureja, A.K.; Sinha, S.K.; Pawaskar, D.N.; Seshu, P.; Chakravartty, J.K.; Sinha, R.K.

    2014-01-01

    Under a postulated accident scenario of loss of cooling medium in an Indian Pressurised Heavy Water Reactor (IPHWR), temperature of the pressure tubes can rise and lead to large deformations. In order to investigate the modes of deformation of pressure tube – calandria tube assembly, material property data defining the flow behaviour over a temperature range from room temperature (RT) to 800 o C are needed. It is of practical importance to formulate mathematical equations to describe the stress–strain relationships of a material for a variety of reasons, such as the analysis of forming operations and the assessment of component's performance in service. A number of constitutive relations of empirical nature have been proposed and they have been found very suitable to describe the behaviour of a material. Although these relations are of empirical nature, various metallurgical factors appear to decide applicability of each of these relations. For example, grain size influences mainly the friction stress while the strain hardening is governed by dislocation density. In a recent work, tensile deformation behaviour of pressure tube material of IPHWR has been carried out over a range of temperature and strain rates (Dureja et al., 2011). It has been found that the strength parameters (yield and ultimate tensile strength) vary along the length of the tube with higher strength at the trailing end as compared to the leading end. This stems from cooling of the billet during the extrusion process which results in the variation of microstructure, texture and dislocation density from the leading to the trailing end. In addition, the variation in metallurgical parameters is also expected to influence the work hardening behaviour, which is known to control the plastic instability (related to uniform strain). In the present investigation, the tensile flow and work-hardening behaviour of a cold worked Zr–2.5Nb pressure tube material of IPHWRs has been studied over the

  15. Analysis of elevated temperature flow and work hardening behaviour of service-exposed 2.25Cr-1Mo steel using Voce equation

    International Nuclear Information System (INIS)

    Girish Shastry, C.; Mathew, M.D.; Bhanu Sankara Rao, K.; Mannan, S.L.

    2004-01-01

    The Voce equation was used to model the tensile flow and work-hardening behaviour of a service-exposed 2.25Cr-1Mo steel. The applicability of Voce parameters obtained from the fit to experimental true stress-true strain datasets for estimating the validity of the fit was examined. The Voce equation was found to model the stress-strain curve closely. The Voce parameter n v was correlated to the underlying dislocation activities. It was found that the values of Voce parameters at various temperatures and strain rates can be used to infer the operating recovery mechanism during stage III hardening. A low absolute value of n v is indicative of recovery by cross-slip, whereas the high temperature transition to climb or sub-boundary migration driven recovery is accompanied by an increase in the value of n v

  16. RHOBOT: Radiation hardened robotics

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, P.C.; Posey, L.D. [Sandia National Labs., Albuquerque, NM (United States)

    1997-10-01

    A survey of robotic applications in radioactive environments has been conducted, and analysis of robotic system components and their response to the varying types and strengths of radiation has been completed. Two specific robotic systems for accident recovery and nuclear fuel movement have been analyzed in detail for radiation hardness. Finally, a general design approach for radiation-hardened robotics systems has been developed and is presented. This report completes this project which was funded under the Laboratory Directed Research and Development program.

  17. RHOBOT: Radiation hardened robotics

    International Nuclear Information System (INIS)

    Bennett, P.C.; Posey, L.D.

    1997-10-01

    A survey of robotic applications in radioactive environments has been conducted, and analysis of robotic system components and their response to the varying types and strengths of radiation has been completed. Two specific robotic systems for accident recovery and nuclear fuel movement have been analyzed in detail for radiation hardness. Finally, a general design approach for radiation-hardened robotics systems has been developed and is presented. This report completes this project which was funded under the Laboratory Directed Research and Development program

  18. Writing parallel programs that work

    CERN Multimedia

    CERN. Geneva

    2012-01-01

    Serial algorithms typically run inefficiently on parallel machines. This may sound like an obvious statement, but it is the root cause of why parallel programming is considered to be difficult. The current state of the computer industry is still that almost all programs in existence are serial. This talk will describe the techniques used in the Intel Parallel Studio to provide a developer with the tools necessary to understand the behaviors and limitations of the existing serial programs. Once the limitations are known the developer can refactor the algorithms and reanalyze the resulting programs with the tools in the Intel Parallel Studio to create parallel programs that work. About the speaker Paul Petersen is a Sr. Principal Engineer in the Software and Solutions Group (SSG) at Intel. He received a Ph.D. degree in Computer Science from the University of Illinois in 1993. After UIUC, he was employed at Kuck and Associates, Inc. (KAI) working on auto-parallelizing compiler (KAP), and was involved in th...

  19. Grind hardening process

    CERN Document Server

    Salonitis, Konstantinos

    2015-01-01

    This book presents the grind-hardening process and the main studies published since it was introduced in 1990s.  The modelling of the various aspects of the process, such as the process forces, temperature profile developed, hardness profiles, residual stresses etc. are described in detail. The book is of interest to the research community working with mathematical modeling and optimization of manufacturing processes.

  20. Kinetic characterization and of recrystallization of the aluminum alloy 6063 after S work hardening treatment; Caracterizacao e cinetica de recristalizacao da liga de aluminio 6063 apos tratamentos termomecanicos

    Energy Technology Data Exchange (ETDEWEB)

    Esposito, Iara Maria

    2006-07-01

    The aluminum 6063 alloy possesses a great industrial interest, presenting characteristics that justify its frequent use, when compared to the other aluminum alloys: the precipitation hardening and high cold work capacity. These alloys present high ductility, that allows their use in operations with high deformation degrees, as the cold work. The objective of this work is to show comparative analysis of the hardness Vickers of the commercial aluminum 6063 alloy, after cold work with different area reduction degree and thermal treatment. Considering the frequent utilization aluminium 6063 alloy, this work studies the characterization and recrystallization of this alloy, after the plastic deformation in different area reduction degrees, thermal treatment and convenient treatment times - Thermo mechanic Treatments. (author)

  1. Effect of iron addition on the work-hardening characteristics of Al-16 wt%Ag alloy

    International Nuclear Information System (INIS)

    Abd El-Salam, F.; Mahmoud, M.A.; Abd El-Khalek, A.M.; Nada, R.H.

    2002-01-01

    The effect of pre-aging time (up to 120 min) and temperatures (428-498 K) on the stress-strain characteristics of Al-16 wt%Ag and Al-16 wt%Ag-0.28 wt%Fe alloys was investigated at different deformation temperatures in the range 353-413 K. The tensile parameters measured for both alloys showed general increase with increasing pre-aging time at 428 and 458 K, while the samples pre-aged at 498 K showed initial softening up to pre-aging time of 60 min followed by increased hardening for longer pre-aging times. The Fe-free samples were generally harder than the ternary samples. The activation energy of the fracture mechanism in both alloys was around 28 kJ/mol

  2. Improving significantly the failure strain and work hardening response of LPSO-strengthened Mg-Y-Zn-Al alloy via hot extrusion speed control

    Science.gov (United States)

    Tan, Xinghe; Chee, Winston; Chan, Jimmy; Kwok, Richard; Gupta, Manoj

    2017-07-01

    The effect of hot extrusion speed on the microstructure and mechanical properties of MgY1.06Zn0.76Al0.42 (at%) alloy strengthened by the novel long-period stacking ordered (LPSO) phase was systematically investigated. Increase in the speed of extrusion accelerated dynamic recrystallization of α-Mg via particle-stimulated nucleation and grain growth in the alloy. The intensive recrystallization and grain growth events weakened the conventional basal texture and Hall-Petch strengthening in the alloy which led to significant improvement in its failure strain from 4.9% to 19.6%. The critical strengthening contribution from LPSO phase known for attributing high strength to the alloy was observed to be greatly undermined by the parallel competition from texture weakening and the adverse Hall-Petch effect when the alloy was extruded at higher speed. Absence of work hardening interestingly observed in the alloy extruded at lower speed was discussed in terms of its ultra-fine grained microstructure which promoted the condition of steady-state defect density in the alloy; where dislocation annihilation balances out the generation of new dislocations during plastic deformation. One approach to improve work hardening response of the alloy to prevent unstable deformation and abrupt failure in service is to increase the grain diameter in the alloy by judiciously increasing the extrusion speed.

  3. Influences of silicon on the work hardening behavior and hot deformation behavior of Fe–25 wt%Mn–(Si, Al) TWIP steel

    International Nuclear Information System (INIS)

    Li, Dejun; Feng, Yaorong; Song, Shengyin; Liu, Qiang; Bai, Qiang; Ren, Fengzhang; Shangguan, Fengshou

    2015-01-01

    Highlights: • Influence of Si on work hardening behavior of Fe–25 wt%Mn TWIP steel was investigated. • Influence of Si on hot deformation behavior of Fe–25 wt%Mn TWIP steel was studied. • Si blocks dislocation glide and favors mechanical twinning in Fe–25 wt%Mn TWIP steel. • The addition of Si increases the hot deformation activation energy of Fe–25 wt%Mn TWIP steel. • The addition of Si retards the nucleation and growth of DRX grains of Fe–25 wt%Mn TWIP steel. - Abstract: The influence of silicon on mechanical properties and hot deformation behavior of austenitic Fe–25 wt%Mn TWIP steel was investigated by means of the comparison research between 25Mn3Al and 25Mn3Si3Al steel. The results show that the 25Mn3Si3Al steel has higher yield strength and higher hardness than that of 25Mn3Al steel because of the solution strengthening caused by Si atoms and possesses higher uniform deformation ability and tensile strength than that of 25Mn3Al steel due to the higher work hardening ability of 25Mn3Si3Al steel. 25Mn3Si3Al steel presents a clear four-stage curve of work hardening rate in course of cold compression. Quite the opposite, the 25Mn3Al steel presents a monotonic decline curve of work hardening rate. The difference of the work hardening behavior between 25Mn3Al and 25Mn3Si3Al steel can be attributed to the decline of stacking fault energy (SFE) caused by the addition of 3 wt% Si. The dislocation glide plays an important role in the plastic deformation of 25Mn3Al steel even though the mechanical twinning is still one of the main deformation mechanisms. The 3 wt% Si added into the 25Mn3Al steel blocks the dislocation glide and promotes the mechanical twinning, and then the dislocation glide characteristics cannot be observed in cold deformed microstructure of 25Mn3Si3Al steel. The hot compression tests reveal that the hot deformation resistance of the 25Mn3Si3Al steel is significantly higher than that of the 25Mn3Al steel due to the solid

  4. A hardenability test proposal

    Energy Technology Data Exchange (ETDEWEB)

    Murthy, N.V.S.N. [Ingersoll-Rand (I) Ltd., Bangalore (India)

    1996-12-31

    A new approach for hardenability evaluation and its application to heat treatable steels will be discussed. This will include an overview and deficiencies of the current methods and discussion on the necessity for a new approach. Hardenability terminology will be expanded to avoid ambiguity and over-simplification as encountered with the current system. A new hardenability definition is proposed. Hardenability specification methods are simplified and rationalized. The new hardenability evaluation system proposed here utilizes a test specimen with varying diameter as an alternative to the cylindrical Jominy hardenability test specimen and is readily applicable to the evaluation of a wide variety of steels with different cross-section sizes.

  5. Comparative tensile flow and work hardening behaviour of thin section and forged thick section 9Cr–1Mo ferritic steel in the framework of Voce equation and Kocks–Mecking approach

    International Nuclear Information System (INIS)

    Choudhary, B.K.; Rao Palaparti, D.P.

    2012-01-01

    Detailed analysis indicated that true stress (σ)-true plastic strain (ε) and work hardening behaviour of 9Cr–1Mo steel in two different forms, i.e. 20 mm plate and thick section tubeplate forging can be adequately described by Voce equation and Kocks–Mecking approach in the temperature range 300–873 K. The steel exhibited two-stage work hardening in the variations of instantaneous work hardening rate (θ = dσ/dε) and θσ with stress. The variations in σ–ε, work hardening parameters, θ–σ and θσ–σ with temperature exhibited three distinct temperature regimes. Good correlations between the predicted tensile properties using Voce equation and the respective experimental values along with analogy between Voce equation and Kocks–Mecking approach have been demonstrated for the steel. The differences in σ–ε, work hardening parameters, θ–σ and θσ–σ observed between plate and tubeplate forging have been ascribed to the effects associated with initial microstructures for the two product forms of the steel.

  6. Strong work-hardening behavior induced by the solid solution strengthening of dendrites in TiZr-based bulk metallic glass matrix composites

    Energy Technology Data Exchange (ETDEWEB)

    Ma, D.Q. [State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004 (China); Jiao, W.T. [College of Education, Hebei Normal University of Science and Technology, Qinhuangdao 066004 (China); Zhang, Y.F. [State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004 (China); Hebei Vocational and Technical College of Building Materials, Qinhuangdao 066004 (China); Wang, B.A.; Li, J.; Zhang, X.Y. [State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004 (China); Ma, M.Z., E-mail: mz550509@ysu.edu.cn [State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004 (China); Liu, R.P. [State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004 (China)

    2015-03-05

    Highlights: • Hardness of dendrite of TiZr-based BMGMCs increases. • Strong work-hardening behavior is obtained after solid solution strengthening. • Lattice distortions of dendrite suffering from rapid cooling are detected. - Abstract: A series of TiZr-based bulk metallic glass matrix composites (BMGMCs) with distinguished mechanical properties are successfully fabricated by adding different volume fractions of Ta (Ti{sub 38.8}Zr{sub 28.8}Cu{sub 6.2}Be{sub 16.2}Nb{sub 10} as the basic composition, denoted as Ta{sub 0.0}–Ta{sub 8.0}). Along with the growth of precipitated phase, typical dendritic morphology is fully developed in the TiZr-based BMGMCs of Ta{sub 8.0}. Energy-dispersive spectrometry analysis of the dendrites and glass matrix indicates that the metallic elements of Nb and Ta should preferentially form solid solution into dendrites. The chaotic structure of high-temperature precipitate phase is trapped down by the rapid cooling of the copper-mould. The detected lattice distortions in the dendrites are attributed to the strong solid solution strengthening of the metallic elements of Ti, Zr, Nb, and Ta. These lattice distortions increase the resistance of the dislocation motion and pin the dislocations, thus the strength and hardness of dendrite increase. Dendrites create a strong barrier for the shear band propagation and generate multiple shear bands after solid solution strengthening, thereby providing the TiZr-based BMGMCs with greatly improved capacity to sustain plastic deformation and resistance to brittle fracture. Thus, the TiZr-based BMGMCs possess distinguished work-hardening capability. Among these TiZr-based BMGMCs, the sample Ta{sub 0.5} possesses the largest plastic strain (ε{sub p}) at 20.3% and ultimate strength (σ{sub max}) of 2613 MPa during compressive loading. In addition, the sample of Ta{sub 0.5} exhibits work-hardening up to an ultrahigh tensile strength of 1680 MPa during the tensile process, and then progressively

  7. Process design of press hardening with gradient material property influence

    International Nuclear Information System (INIS)

    Neugebauer, R.; Schieck, F.; Rautenstrauch, A.

    2011-01-01

    Press hardening is currently used in the production of automotive structures that require very high strength and controlled deformation during crash tests. Press hardening can achieve significant reductions of sheet thickness at constant strength and is therefore a promising technology for the production of lightweight and energy-efficient automobiles. The manganese-boron steel 22MnB5 have been implemented in sheet press hardening owing to their excellent hot formability, high hardenability, and good temperability even at low cooling rates. However, press-hardened components have shown poor ductility and cracking at relatively small strains. A possible solution to this problem is a selective increase of steel sheet ductility by press hardening process design in areas where the component is required to deform plastically during crash tests. To this end, process designers require information about microstructure and mechanical properties as a function of the wide spectrum of cooling rates and sequences and austenitizing treatment conditions that can be encountered in production environments. In the present work, a Continuous Cooling Transformation (CCT) diagram with corresponding material properties of sheet steel 22MnB5 was determined for a wide spectrum of cooling rates. Heating and cooling programs were conducted in a quenching dilatometer. Motivated by the importance of residual elasticity in crash test performance, this property was measured using a micro-bending test and the results were integrated into the CCT diagrams to complement the hardness testing results. This information is essential for the process design of press hardening of sheet components with gradient material properties.

  8. Magnetic small-angle scattering of subthermal neutrons by internal stress fields in work-hardened nickel single crystals oriented for multiple glide

    International Nuclear Information System (INIS)

    Vorbrugg, W.; Schaerpf, O.

    1975-01-01

    The small-angle scattering of Ni single crystals with (111) and (100) axis orientation is measured by a photographic method in the work-hardened state after tensile deformation. Parameters are the external magnetic field H parallel to the axis (600 2 ]<=8,8), and the elastic stress tausub(el)(0<=tausub(el)<=tausub(pl)) applied to the deformed crystals during the experiments. The scattering is found to be anisotropic and characteristic for the chosen orientation. The quantitative photometric analysis shows that the parameters mentioned above only influence the intensity but not the distribution of the scattered neutrons. The scattering increases with the elastic stress and decreases with the magnetic field. In particular, in the unloaded state there is a linear relation between the scattered intensity and the plastic shear stress. (author)

  9. Comparison of Thermal Creep Strain Calculation Results Using Time Hardening and Strain Hardening Rules

    International Nuclear Information System (INIS)

    Kim, Junehyung; Cheon, Jinsik; Lee, Byoungoon; Lee, Chanbock

    2014-01-01

    One of the design criteria for the fuel rod in PGSFR is the thermal creep strain of the cladding, because the cladding is exposed to a high temperature for a long time during reactor operation period. In general, there are two kind of calculation scheme for thermal creep strain: time hardening and strain hardening rules. In this work, thermal creep strain calculation results for HT9 cladding by using time hardening and strain hardening rules are compared by employing KAERI's current metallic fuel performance analysis code, MACSIS. Also, thermal creep strain calculation results by using ANL's metallic fuel performance analysis code, LIFE-METAL which adopts strain hardening rule are compared with those by using MACSIS. Thermal creep strain calculation results for HT9 cladding by using time hardening and strain hardening rules were compared by employing KAERI's current metallic fuel performance analysis code, MACSIS. Also, thermal creep strain calculation results by using ANL's metallic fuel performance analysis code, LIFE-METAL which adopts strain hardening rule were compared with those by using MACSIS. Tertiary creep started earlier in time hardening rule than in strain hardening rule. Also, calculation results by MACSIS with strain hardening and those obtained by using LIFE-METAL were almost identical to each other

  10. [IBM Work and Personal Life Balance Programs.

    Science.gov (United States)

    International Business Machines Corp., Armonk, NY.

    These five brochures describe the IBM Corporation's policies, programs, and initiatives designed to meet the needs of employees' child care and family responsibilities as they move through various stages of employment with IBM. The Work and Personal Life Balance Programs brochure outlines (1) policies for flexible work schedules, including…

  11. Repository-Based Software Engineering Program: Working Program Management Plan

    Science.gov (United States)

    1993-01-01

    Repository-Based Software Engineering Program (RBSE) is a National Aeronautics and Space Administration (NASA) sponsored program dedicated to introducing and supporting common, effective approaches to software engineering practices. The process of conceiving, designing, building, and maintaining software systems by using existing software assets that are stored in a specialized operational reuse library or repository, accessible to system designers, is the foundation of the program. In addition to operating a software repository, RBSE promotes (1) software engineering technology transfer, (2) academic and instructional support of reuse programs, (3) the use of common software engineering standards and practices, (4) software reuse technology research, and (5) interoperability between reuse libraries. This Program Management Plan (PMP) is intended to communicate program goals and objectives, describe major work areas, and define a management report and control process. This process will assist the Program Manager, University of Houston at Clear Lake (UHCL) in tracking work progress and describing major program activities to NASA management. The goal of this PMP is to make managing the RBSE program a relatively easy process that improves the work of all team members. The PMP describes work areas addressed and work efforts being accomplished by the program; however, it is not intended as a complete description of the program. Its focus is on providing management tools and management processes for monitoring, evaluating, and administering the program; and it includes schedules for charting milestones and deliveries of program products. The PMP was developed by soliciting and obtaining guidance from appropriate program participants, analyzing program management guidance, and reviewing related program management documents.

  12. The secondary hardening phenomenon in strain-hardened MP35N alloy

    International Nuclear Information System (INIS)

    Asgari, S.; El-Danaf, E.; Shaji, E.; Kalidindi, S.R.; Doherty, R.D.

    1998-01-01

    Mechanical testing and microscopy techniques were used to investigate the influence of aging on the structure and strengthening of MP35N alloy. It was confirmed that aging the deformed material at 600 C for 4 h provided additional strengthening, here referred to as secondary hardening, in addition to the primary strain hardening. The secondary hardening phenomenon was shown to be distinctly different from typical age hardening processes in that it only occurred in material deformed beyond a certain cold work level. At moderate strains, aging caused a shift in the entire stress-strain curve of the annealed material to higher stresses while at high strains, it produced shear localization and limited work softening. The secondary hardening increment was also found to be grain size dependent. The magnitude of the secondary hardening appeared to be controlled by the flow stress in the strain hardened material. A model is proposed to explain the observations and is supported by direct experimental evidence. The model is based on formation of h.c.p. nuclei through the Suzuki mechanism, that is segregation of solute atoms to stacking faults, on aging the strain hardened material. The h.c.p. precipitates appear to thicken only in the presence of high dislocation density produced by prior cold work

  13. A unified theoretical and experimental study of anisotropic hardening

    International Nuclear Information System (INIS)

    Boehler, J.P.; Raclin, J.

    1981-01-01

    The purpose of this work is to develop a consistent formulation of the constitutive relations regarding anisotropic hardening materials. Attention is focused on the appearance and the evolution of mechanical anisotropies during irreversible processes, such as plastic forming and inelastic deformation of structures. The representation theorems for anisotropic tensor functions constitute a theoretical basis, allowing to reduce arbitrariness and to obtain a unified formulation of anisotropic hardening. In this approach, a general three-dimensional constitutive law is developed for prestrained initially orthotropic materials. Introduction of the plastic behavior results in the general forms of both the flow-law and the yield criterion. The developed theory is then specialized for the case of plane stress and different modes of anisotropic hardening are analyzed. A new generalization of the Von Mises criterion is proposed, in considering a homogeneous form of order two in stress and employing the simplest combinations of the basic invariants entering the general form of the yield condition. The proposed criterion involves specific terms accounting for the initial anisotropy, the deformation induced anisotropy and correlative terms between initial and induced anisotropy. The effects of prestrainings result in both isotropic and anisotropic hardening. An adequate experimental program, consisting of uniaxial tensile tests on oriented specimens of prestrained sheet-metal, was performed, in order to determine the specific form and the evolution of the anisotropic failure criterion for soft-steel subjected to different irreversible prestrainings. (orig.)

  14. Radiation hardening of semiconductor parts

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    This chapter is an overview of total-ionizing-dose and single-event hardening techniques and should be used as a guide to a range of research publications. It should be stressed that there is no clear and simple route to a radiation-tolerant silicon integrated circuit. What works for one fabrication process may not work for another, and there are many complex interactions within individual processes and designs. The authors have attempted to highlight the most important factors and those process changes which should bring improved hardness. The main point is that radiation-hardening as a procedure must be approached in a methodical fashion and with a good understanding of the response mechanisms involved

  15. COMPLEX SURFACE HARDENING OF STEEL ARTICLES

    Directory of Open Access Journals (Sweden)

    A. V. Kovalchuk

    2014-01-01

    Full Text Available The method of complex surface hardening of steel detailswas designed. The method is a compound of two processes of hardening: chemical heat treatment and physical vapor deposition (PVD of the coating. The result, achieved in this study is much higher, than in other work on this topic and is cumulative. The method designed can be used in mechanical engineering, medicine, energetics and is perspective for military and space technologies.

  16. Programs that work : California case examples

    Energy Technology Data Exchange (ETDEWEB)

    Rodgrigues, G. [Southern California Edison, Rosemead, CA (United States)

    2007-07-01

    Examples of programs that work in California with respect to greenhouse gas emissions were discussed. Specifically, Southern California Edison (SCE) was noted as one of the country's largest investor-owned utilities that has provided environmental leadership in this area. Energy, environment, economy, and community were mentioned as being the four value propositions for demand side management (DSM) programs. The environmental benefits of California investor-owned utilities programs were also discussed. Customer participation in SCE's energy efficiency programs was defined as an important measure of success. Other topics that were addressed in the presentation included energy efficiency in the long-term resource plan; ratcheting codes and standards; effective marketing and outreach; residential and non-residential programs; partnership programs; and competitively-selected programs. Measurement, verification and evaluation were noted as being real savings. Initiatives on the horizon such as the California solar initiative and Edison smartconnect were presented. tabs., figs.

  17. Programs that work : California case examples

    International Nuclear Information System (INIS)

    Rodgrigues, G.

    2007-01-01

    Examples of programs that work in California with respect to greenhouse gas emissions were discussed. Specifically, Southern California Edison (SCE) was noted as one of the country's largest investor-owned utilities that has provided environmental leadership in this area. Energy, environment, economy, and community were mentioned as being the four value propositions for demand side management (DSM) programs. The environmental benefits of California investor-owned utilities programs were also discussed. Customer participation in SCE's energy efficiency programs was defined as an important measure of success. Other topics that were addressed in the presentation included energy efficiency in the long-term resource plan; ratcheting codes and standards; effective marketing and outreach; residential and non-residential programs; partnership programs; and competitively-selected programs. Measurement, verification and evaluation were noted as being real savings. Initiatives on the horizon such as the California solar initiative and Edison smartconnect were presented. tabs., figs

  18. Energetic model of metal hardening

    Directory of Open Access Journals (Sweden)

    Ignatova O.N.

    2011-01-01

    Full Text Available Based on Bailey hypothesis on the link between strain hardening and elastic lattice defect energy this paper suggests a shear strength energetic model that takes into consideration plastic strain intensity and rate as well as softening related to temperature annealing and dislocation annihilation. Metal strain hardening was demonstrated to be determined only by elastic strain energy related to the energy of accumulated defects. It is anticipated that accumulation of the elastic energy of defects is governed by plastic work. The suggested model has a reasonable agreement with the available experimental data for copper up to P = 70 GPa , for aluminum up to P = 10 GPa and for tantalum up to P = 20 GPa.

  19. Training program attracts work and health researchers

    DEFF Research Database (Denmark)

    Skakon, Janne

    2007-01-01

    Each year in Canada, the costs of disability arising from work-related causes – including workers’ compensation and health-care costs – exceed $6.7 billion. Despite the significant financial and social impacts of worker injury and illness, only a small fraction of Canadian researchers are dedicated...... to examining work disability prevention issues. An innovative program that attracts international students, the Work Disability Prevention Canadian Institutes of Health Research (CIHR) Strategic Training Program, aims to build research capacity in young researchers and to create a strong network that examines...

  20. Orchestration in work environment policy programs

    DEFF Research Database (Denmark)

    Hasle, Peter; Limborg, Hans Jørgen; Grøn, Sisse

    2017-01-01

    In spite of many years’ efforts, it is difficult to prove substantial improvements of the work environment and policymakers are continuously searching for new efficient strategies. This paper examines the concept of orchestration of work environment programs, based on an empirical analysis...... of recent Danish policy. Orchestration is a strategy where different stakeholders and activities are integrated into a unified program aimed at a specific target group. The analysis includes three policy cases, supplemented with two company case studies. The research shows a move toward a more governance...... type of regulation, which is not only emerging in network but also includes more explicitly orchestrated policy programs. The stakeholders participate in the network with different interests and the orchestration of work environment policies is therefore built on a platform of regulation...

  1. Effect of aging and cold working on the high-temperature low-cycle fatigue behavior of alloy 800H. Part I. The effect of hardening processes on the initial stress--strain curve

    International Nuclear Information System (INIS)

    Villagrana, R.E.; Kaae, J.L.; Ellis, J.R.; Gantzel, P.K.

    1978-01-01

    The individual and combined effects of cold working (5 and 10%) and aging (4000 and 8000 h at 538 to 760 0 C) on the microstructure and high-temperature yield strength of alloy 800H have been investigated. The specimens were tested at the aging temperatures. During testing some of the specimens showed the phenomenon of serrated yielding. In order of importance, the principal hardening agents observed in this work were: cold work, the precipitation of Cr 23 C 6 at the grain boundaries, and, in some cases, the precipitation of a Perovskite-type γ' phase in the grain interiors

  2. Induction Hardening of External Gear

    Science.gov (United States)

    Bukanin, V. A.; Ivanov, A. N.; Zenkov, A. E.; Vologdin, V. V.; Vologdin, V. V., Jr.

    2018-03-01

    Problems and solution of gear induction hardening are described. Main attention is paid to the parameters of heating and cooling systems. ELTA 7.0 program has been used to obtain the required electrical parameters of inductor, power sources, resonant circuits, as well as to choose the quenching media. Comparison of experimental and calculated results of investigation is provided. In order to compare advantages and disadvantages of single- and dual-frequency heating processes, many variants of these technologies were simulated. The predicted structure and hardness of steel gears are obtained by use of the ELTA data base taken into account the Continuous Cooling Transformation diagrams.

  3. Collaborative Communication in Work Based Learning Programs

    Science.gov (United States)

    Wagner, Stephen Allen

    2017-01-01

    This basic qualitative study, using interviews and document analysis, examined reflections from a Work Based Learning (WBL) program to understand how utilizing digital collaborative communication tools influence the educational experience. The Community of Inquiry (CoI) framework was used as a theoretical frame promoting the examination of the…

  4. Hardening Azure applications

    CERN Document Server

    Gaurav, Suraj

    2015-01-01

    Learn what it takes to build large scale, mission critical applications -hardened applications- on the Azure cloud platform. This 208 page book covers the techniques and engineering principles that every architect and developer needs to know to harden their Azure/.NET applications to ensure maximum reliability and high availability when deployed at scale. While the techniques are implemented in .NET and optimized for Azure, the principles here will also be valuable for users of other cloud-based development platforms. Applications come in a variety of forms, from simple apps that can be bui

  5. Radiation hardenable coating mixture

    International Nuclear Information System (INIS)

    Howard, D.D.

    1977-01-01

    This invention relates to coatings that harden under radiation and to their compositions. Specifically, this invention concerns unsaturated urethane resins polymerisable by addition and to compositions, hardening under the effect of radiation, containing these resins. These resins feature the presence of at least one unsaturated ethylenic terminal group of structure CH 2 =C and containing the product of the reaction of an organic isocyanate compound with at least two isocyanate groups and one polyester polyol with at least two hydroxyl groups, and one unsaturated monomer compound polymerisable by addition having a single active hydrogen group reacting with the isocyanate [fr

  6. Concrete, hardened: Self desiccation

    DEFF Research Database (Denmark)

    Hansen, Ernst Jan De Place; Hansen, Kurt Kielsgaard; Persson, Bertil

    1999-01-01

    The test method covers the determination of internal relative humidity (RH) in hardened concrete and cement mortar using RH instruments. The determination of RH is done on crushed samples of concrete or cement motar. This test method is only for measuring equipment which gives off or takes up...

  7. REBUILD AMERICA PROGRAM SCOPE OF WORK

    Energy Technology Data Exchange (ETDEWEB)

    Jeffrey Brown; Bruce Exstrum

    2004-12-01

    This report summarizes the activities carried out by Aspen Systems Corporation in support of the Department of Energy's Rebuild America program during the period from October 9, 1999 to October 31, 2004. These activities were in accordance with the Scope of Work contained in a GSA MOBIS schedule task order issued by the National Energy Technology Laboratory. This report includes descriptions of activities and results in the following areas: deployment/delivery model; program and project results; program representative support activities; technical assistance; web site development and operation; business/strategic partners; and training/workshop activities. The report includes conclusions and recommendations. Five source documents are also provided as appendices.

  8. Fatigue hardening and softening studies on strain hardened 18-8 austenitic stainless steel

    International Nuclear Information System (INIS)

    Ramakrishna Prasad, C.; Vasudevan, R.

    1976-01-01

    Metals when subjected to fatigue harden or soften depending on their previous mechanical history. Annealed or mildly cold worked metals are known to harden while severely cold worked metals soften when subjected to fatigue loading. In the present work samples of austenitic 18-8 steel cold worked to 11% and 22% reduction in area were mounted in a vertical pulsator and fatigued in axial tension-compression. Clear cut effects were produced and it was noticed that these depended on the extent of cold work, the amplitude as well as the number of cycles of fatigue and mean stress if any. (orig.) [de

  9. Radiation hardening coating material

    International Nuclear Information System (INIS)

    McDonald, W.H.; Prucnal, P.J.; DeMajistre, Robert.

    1977-01-01

    This invention concerns a radiation hardening coating material. First a resin is prepared by reaction of bisphenol diglycidylic ether with acrylic or methacrylic acids. Then the reactive solvent is prepared by reaction of acrylic or methacrylic acids with epichlorhydrine or epibromhydrine. Then a solution consisting of the resin dissolved in the reactive solvent is prepared. A substrate (wood, paper, polyesters, polyamines etc.) is coated with this composition and exposed to ionizing radiations (electron beams) or ultraviolet radiations [fr

  10. 28 CFR 545.23 - Inmate work/program assignment.

    Science.gov (United States)

    2010-07-01

    ... community living area, unless the pretrial inmate has signed a waiver of his or her right not to work (see... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Inmate work/program assignment. 545.23... WORK AND COMPENSATION Inmate Work and Performance Pay Program § 545.23 Inmate work/program assignment...

  11. An outline of 1961 program;IAEA program of work

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1960-09-15

    The program of work for 1961 which the International Atomic Energy Agency's Board of Governors has presented to the Agency's General Conference for final approval provides for steady amplification of its work in technical assistance to specific projects, training of scientific personnel and scientific research. These activities and certain others are of special interest to those areas of the world that are less advanced in the utilization of atomic energy. This is in accord with the Agency's Statute which requires that it bear in mind 'the special needs of the under-developed areas of the world'. At the same time, the Board indicated that the 1961 program 'provides for activities intended to create a basis for general progress in the safe utilization of atomic energy for peaceful purposes which is of concern to all Member States. Thus the delay in the advent of generally economic nuclear power is used to build up the necessary technological infrastructure in the less developed countries and to establish an international framework of norms and regulations which an orderly and safe development of widespread nuclear industries will require'. Some highlights of the 1961 program are presented

  12. Stress corrosion cracking evaluation of precipitation-hardening stainless steel

    Science.gov (United States)

    Humphries, T. S.; Nelson, E. E.

    1970-01-01

    Accelerated test program results show which precipitation hardening stainless steels are resistant to stress corrosion cracking. In certain cases stress corrosion susceptibility was found to be associated with the process procedure.

  13. OCCUPATIONAL ASTHMA CAUSED BY A HARDENER CONTAINING AN ALIPHATIC AND A CYCLOALIPHATIC DIAMINE

    NARCIS (Netherlands)

    ALEVA, RM; AALBERS, R; KOETER, GH; DEMONCHY, JGR

    An otherwise healthy 44-yr-old man experienced a serious attack of bronchial obstruction after working with resins and hardeners, releasing fumes of a mixture of an aliphatic and a cycloaliphatic diamine hardener. Eight hours after deliberate challenge with the hardener a large increase of airway

  14. Radiation-hardened microwave communications system

    International Nuclear Information System (INIS)

    Smith, S.F.; Crutcher, R.I.; Vandermolen, R.I.

    1990-01-01

    The consolidated fuel reprocessing program (CFRP) at the Oak Ridge National Laboratory (ORNL) has been developing signal transmission techniques and equipment to improve the efficiency of remote handling operations for nuclear applications. These efforts have been largely directed toward the goals of (a) remotely controlling bilateral force-reflecting servomanipulators for dexterous manipulation-based operations in remote maintenance tasks and (b) providing television viewing of the work site. In September 1987, developmental microwave transceiving hardware operating with dish antennas was demonstrated in the advanced integrated maintenance system (AIMS) facility at ORNL, successfully implementing both high-quality one-way television transmissions and simultaneous bidirectional digital control data transmissions with very low error rates. Initial test results based on digital transmission at a 1.0-Mbaud data rate indicated that the error rates of the microwave system were comparable to those of a hardwired system. During these test intervals, complex manipulator operations were performed, and the AIMS transporter was moved repeatedly without adverse effects on data integrity. Results of these tests have been factored into subsequent phases of the development program, with an ultimate goal of designing a fully radiation-hardened microwave signal transmission system for use in nuclear facilities

  15. Update on radiation-hardened microcomputers for robotics and teleoperated systems

    International Nuclear Information System (INIS)

    Sias, F.R. Jr.; Tulenko, J.S.

    1993-01-01

    Since many programs sponsored by the Department of Defense are being canceled, it is important to select carefully radiation-hardened microprocessors for projects that will mature (or will require continued support) several years in the future. At the present time there are seven candidate 32-bit processors that should be considered for long-range planning for high-performance radiation-hardened computer systems. For Department of Energy applications it is also important to consider efforts at standardization that require the use of the VxWorks operating system and hardware based on the VMEbus. Of the seven processors, one has been delivered and is operating and other systems are scheduled to be delivered late in 1993 or early in 1994. At the present time the Honeywell-developed RH32, the Harris RH-3000 and the Harris RHC-3000 are leading contenders for meeting DOE requirements for a radiation-hardened advanced 32-bit microprocessor. These are all either compatible with or are derivatives of the MIPS R3000 Reduced Instruction Set Computer. It is anticipated that as few as two of the seven radiation-hardened processors will be supported by the space program in the long run

  16. Bake hardening of nanograin AA7075 aluminum alloy

    International Nuclear Information System (INIS)

    Dehghani, Kamran

    2011-01-01

    Highlights: ► The bake hardening behavior of AA7075 was studied and compared with its coarse-grain counterpart. ► Nanograin AA7075 exhibited 88–100% increase in bake hardenability. ► Nanograin AA7075 exhibited 36–38% increase in final yield strength after baking. ► Maximum bake hardenability and final yield stress were about 185 MPa and 719 MPa. - Abstract: In the present work, the bake hardening of nanostructured AA7075 aluminum alloy was compared with that of its coarse-grain counterpart. Surface severe plastic deformation (SSPD) was used to produce nanograin layers on both surfaces of workpieces. The nanostructured layers were characterized using scanning electron microscopy (SEM) and atomic force microscopy (AFM) techniques. The thickness of nanostructured layer, having the grains of 50–110 nm, was about 75 μm on each side of workpiece. The bake hardenability of nanograin and coarse-grain AA7075 was then compared by pre-straining to 2, 4 and 6% followed by baking at 100 °C and 200 °C for 20 min. Comparing to coarse-grain case, there was about 88–100% increase in bake hardenability and about 36–38% increase in yield strength after the bake hardening of present nanograin AA7075. Such an increase in bake hardenability and strength was achieved when the thickness of two nanograin layers was about only one-tenth of the whole thickness.

  17. Nuclear effects hardened shelters

    International Nuclear Information System (INIS)

    Lindke, P.

    1990-01-01

    This paper reports on the Houston Fearless 76 Government Projects Group that has been actively engaged for more than twenty-five years as a sub-contractor and currently as a prime contractor in the design, manufacture, repair and logistics support of custom mobile ground stations and their equipment accommodations. Other associated products include environmental control units (ECU's), mobilizers for shelters and a variety of mobile power generation units (MPU's). Since 1984, Houston Fearless 76 has designed and manufactured four 8 foot by 8 foot x 22 foot nuclear hardened mobile shelters. These shelters were designed to contain electronic data processing/reduction equipment. One shelter is currently being operated by the Air Force as a Defense Intelligence Agency (DIA) approved and certified Special Compartmented Information Facility (SCIF). During the development and manufacturing process of the shelters, we received continual technical assistance and design concept evaluations from Science Applications International Corporation (SAIC) Operations Analysis and Logistics Engineering Division and the Nondestructive Inspection Lab at McClellan AFB. SAIC was originally employed by the Air Force to design the nuclear hardening specifications applied to these shelters

  18. Is the Infrastructure of EHDI Programs Working?

    Science.gov (United States)

    Houston, K. Todd; Hoffman, Jeff; Munoz, Karen F.; Bradham, Tamala S.

    2011-01-01

    State coordinators of early hearing detection and intervention (EHDI) programs completed a strengths, weaknesses, opportunities, and threats, or SWOT, analysis that consisted of 12 evaluative areas of EHDI programs. For the EHDI program infrastructure area, 47 coordinators responded with a total of 292 items, and themes were identified in each…

  19. State Enterprise Zone Programs: Have They Worked?

    Science.gov (United States)

    Peters, Alan H.; Fisher, Peter S.

    The effectiveness of state enterprise zone programs was examined by using a hypothetical-firm model called the Tax and Incentives Model-Enterprise Zones (TAIM-ez) model to analyze the value of enterprise zone incentives to businesses across the United States and especially in the 13 states that had substantial enterprise zone programs by 1990. The…

  20. Hospital graduate social work field work programs: a study in New York City.

    Science.gov (United States)

    Showers, N

    1990-02-01

    Twenty-seven hospital field work programs in New York City were studied. Questionnaires were administered to program coordinators and 238 graduate social work students participating in study programs. High degrees of program structural complexity and variation were found, indicating a state of art well beyond that described in the general field work literature. High rates of student satisfaction with learning, field instructors, programs, and the overall field work experience found suggest that the complexity of study programs may be more effective than traditional field work models. Statistically nonsignificant study findings indicate areas in which hospital social work departments may develop field work programs consistent with shifting organizational needs, without undue risk to educational effectiveness. Statistically significant findings suggest areas in which inflexibility in program design may be more beneficial in the diagnostic related groups era.

  1. Cognitive work hardening for return to work following depression: An intervention study: Le réentraînement cognitif au travail pour favoriser le retour au travail à la suite d'une dépression : étude d'intervention.

    Science.gov (United States)

    Wisenthal, Adeena; Krupa, Terry; Kirsh, Bonnie H; Lysaght, Rosemary

    2018-02-01

    Work absences due to depression are prevalent; however, few interventions exist to address the return-to-work challenges following a depressive episode. This mixed-methods study aimed to (a) evaluate the effectiveness of cognitive work hardening in preparing people with depression to return to work and (b) identify key elements of the intervention. A single group ( n = 21) pretest-posttest study design was used incorporating self-report measures (Work Ability Index, Multidimensional Assessment of Fatigue, Beck Depression Inventory II) with interviews at intervention completion and at 3-month follow-up. Descriptive statistics, paired-samples t test, and content analysis were used to analyze the data. Work ability, fatigue, and depression severity significantly improved postintervention. Participants identified structure, work simulations, realism of simulated work environment, support, and education as key intervention elements. Findings underscore an occupationally focused return-to-work intervention for people recovering from depression with potential for wider adoption and future research.

  2. 77 FR 27593 - Exchange Visitor Program-Summer Work Travel

    Science.gov (United States)

    2012-05-11

    ...--Summer Work Travel AGENCY: Department of State. ACTION: Interim final rule with request for comment... Travel Program allows foreign post-secondary students (mostly between the ages of 18 and 30) to come to... students have participated in the Sumer Work Travel Program. The popularity of this Program--both with...

  3. Radiation hardening of diagnostics

    International Nuclear Information System (INIS)

    Siemon, R.E.

    1991-01-01

    The world fusion program has advanced to the stage where it is appropriate to construct a number of devices for the purpose of burning DT fuel. In these next-generation experiments, the expected flux and fluence of 14 MeV neutrons and associated gamma rays will pose a significant challenge to the operation and diagnostics of the fusion device. Radiation effects include structural damage to materials such as vacuum windows and seals, modifications to electrical properties such as electrical conductivity and dielectric strength and impaired optical properties such as reduced transparency and luminescence of windows and fiber optics during irradiation. In preparation for construction and operation of these new facilities, the fusion diagnostics community needs to work with materials scientists to develop a better understanding of radiation effects, and to undertake a testing program aimed at developing workable solutions for this multi-faceted problem. A unique facility to help in this regard is the Los Alamos Spallation Radiation Effects Facility, a neutron source located at the beam stop of the world's most powerful accelerator, the Los Alamos Meson Physics Facility (LAMPF). The LAMPF proton beam generates 10 16 neutrons per second because of ''spallation'' reactions when the protons collide with the copper nuclei in the beam stop

  4. Hardening and softening mechanisms of pearlitic steel wire under torsion

    International Nuclear Information System (INIS)

    Zhao, Tian-Zhang; Zhang, Shi-Hong; Zhang, Guang-Liang; Song, Hong-Wu; Cheng, Ming

    2014-01-01

    Highlights: • Mechanical behavior of pearlitic steel wire is studied using torsion. • Work hardening results from refinement lamellar pearlitic structure. • Softening results from recovery, shear bands and lamellar fragmentations. • A microstructure based analytical flow stress model is established. - Abstract: The mechanical behaviors and microstructure evolution of pearlitic steel wires under monotonic shear deformation have been investigated by a torsion test and a number of electron microscopy techniques including scanning electron microscopy (SEM) and transmission electron microscopy (TEM), with an aim to reveal the softening and hardening mechanisms of a randomly oriented pearlitic structure during a monotonic stain path. Significantly different from the remarkable strain hardening in cold wire drawing, the strain hardening rate during torsion drops to zero quickly after a short hardening stage. The microstructure observations indicate that the inter-lamellar spacing (ILS) decreases and the dislocations accumulate with strain, which leads to hardening of the material. Meanwhile, when the strain is larger than 0.154, the enhancement of dynamic recovery, shear bands (SBs) and cementite fragmentations results in the softening and balances the strain hardening. A microstructure based analytical flow stress model with considering the influence of ILS on the mean free path of dislocations and the softening caused by SBs and cementite fragmentations, has been established and the predicted flow shear curve meets well with the measured curve in the torsion test

  5. Is the Texas Pecan Checkoff Program Working?

    OpenAIRE

    Moore, Eli D.; Williams, Gary W.

    2008-01-01

    The Texas Pecan Board was established in 1998 to administer the Texas Pecan Checkoff Program and is financed through a one-half cent per pound assessment on grower pecan sales. The Board spends the assessment collections on a variety of advertising campaigns in an attempt to expand demand for Texas pecans, both improved and native varieties, and increase the welfare of Texas pecan growers. This study presents an evaluation of the economic effectiveness of the Texas Pecan Checkoff Program in e...

  6. Adjuncts in Social Work Programs: Good Practice or Unethical?

    Science.gov (United States)

    Pearlman, Catherine A.

    2013-01-01

    Social work education programs rely heavily on adjunct instructors, as do most academic institutions. This article adds to existing literature on adjuncts by focusing on the unique issues in social work education, using social work values and ethics as a focus. The benefits and detriments for adjuncts, programs, and students in schools of social…

  7. Work program analysis - defining the capability/risk plan

    International Nuclear Information System (INIS)

    Hrinivich, W.A.

    2004-01-01

    Bruce Power has developed and implemented an analysis methodology (Work Program Analysis) to assess and address corporate business risk associated with work group capability. Work Program Analysis is proving to be an excellent tool for identifying and supporting key business decisions facing the line and senior management at Bruce Power. The following describes the methodology, its application and the results achieved. (author)

  8. Radiation-hardened optoelectronic components: detectors

    International Nuclear Information System (INIS)

    Wiczer, J.J.

    1986-01-01

    In this talk, we will survey recent research in the area of radiation hardened optical detectors. We have studied conventional silicon photodiode structures, special radiation hardened silicon photodiodes, and special double heterojunction AlGaAs/GaAs photodiodes in neutron, gamma, pulsed x-ray and charged particle environments. We will present results of our work and summarize other research in this area. Our studies have shown that detectors can be made to function acceptably after exposures to neutron fluences of 10 15 n/cm 2 , total dose gamma exposures of 10 8 rad (Si), and flash x-ray environments of 10 8 rad/sec (Si). We will describe detector structures that can operate through these conditions, pre-rad and post-rad operational characteristics, and experimental conditions that produced these results. 23 refs., 10 figs., 1 tab

  9. EDF program on SCC initiation of cold-worked stainless steels in primary water

    Energy Technology Data Exchange (ETDEWEB)

    Huguenin, P.; Vaillant, F.; Couvant, T. [Electricite de France (EDF/RD), Site des Renardieres, 77 - Moret sur loing (France); Buisse, L. [EDF UTO, 93 - Noisy-Le-Grand (France); Huguenin, P.; Crepin, J.; Duhamel, C.; Proudhon, H. [MINES ParisTech, Centre des Materiaux, 91 - Evry (France); Ilevbare, G. [EPRI California (United States)

    2009-07-01

    A few cases of Intergranular Stress Corrosion Cracking (IGSCC) on cold-worked austenitic stainless steels in primary water have been detected in French Pressurized Water Reactors (PWRs). A previous program launched in the early 2000's identified the required conditions for SCC of cold-worked stainless steels. It was found that a high strain hardening coupled with cyclic loading favoured SCC, whereas cracking under static conditions appeared to be difficult. A propagation model was also proposed. The first available results of the present study demonstrate the strong influence of a trapezoidal cyclic loading on the creep of 304L austenitic stainless steel. While no creep was detected under a pure static loading, the creep rate was increased by a factor 102 under a trapezoidal cyclic loading. The first results of SCC initiation performed on notched specimens under a trapezoidal cyclic loading at low frequency are presented. The present study aims at developing an engineering model for IGSCC initiation of 304L, 316L and weld 308L stainless steels. The effect of the pre-straining on the SCC mechanisms is more specifically studied. Such a model will be based on (i) SCC initiation tests on notched and smooth specimens under 'trapezoidal' cyclic loading and, (ii) constant strain rate SCC initiation tests. The influence of stress level, cold-work level, strain path, surface roughness and temperature is particularly investigated. (authors)

  10. The Teaching of Work Ethics: Current Practices of Work Program Coordinators in Georgia.

    Science.gov (United States)

    Ford, Frances Annette; Herren, Ray V.

    A study examined the perceptions and practices of 160 work program coordinators in Georgia (44% of the sample) regarding the teaching of work ethics. A literature review had shown that a consistent view of potential employers was that graduates of vocational education programs should be well grounded in the concept of work ethics. The main purpose…

  11. Fatigue of coated and laser hardened steels

    International Nuclear Information System (INIS)

    La Cruz, P. de.

    1990-01-01

    In the present work the effect of ion nitriding, laser hardening and hot dip galvanizing upon the fatigue limit and notch sensitivity of a B-Mn Swedish steel SS 2131 have been investigated. The fatigue tests were performed in plane reverse bending fatigue (R=1). The quenched and tempered condition was taken as the reference condition. The microstructure, microhardness, fracture surface and coating appearance of the fatigue surface treated specimens were studied. Residual stress and retained austenite measurements were also carried out. It was found that ion nitriding improves the fatigue limit by 53 % for smooth specimens and by 115 % for notched specimens. Laser hardening improves the fatigue limit by 18 % and 56 % for smooth and notched specimen respectively. Hot dip galvanizing gives a slight deterioration of the fatigue limit (9 % and 10 % for smooth and notched specimen respectively). Ion nitriding and laser hardening decrease the value of the notch sensitivity factor q by 78 % and 65 % respectively. Hot dip galvanizing does not modify it. A simple schematic model based on a residual stress distribution, has been used to explain the different effects. It seems that the presence of the higher compressive residual stresses and the higher uniformity of the microstructure may be the causes of the better fatigue performance of ion nitrided specimens. (119 refs.) (author)

  12. Beam hardening correction algorithm in microtomography images

    International Nuclear Information System (INIS)

    Sales, Erika S.; Lima, Inaya C.B.; Lopes, Ricardo T.; Assis, Joaquim T. de

    2009-01-01

    Quantification of mineral density of bone samples is directly related to the attenuation coefficient of bone. The X-rays used in microtomography images are polychromatic and have a moderately broad spectrum of energy, which makes the low-energy X-rays passing through a sample to be absorbed, causing a decrease in the attenuation coefficient and possibly artifacts. This decrease in the attenuation coefficient is due to a process called beam hardening. In this work the beam hardening of microtomography images of vertebrae of Wistar rats subjected to a study of hyperthyroidism was corrected by the method of linearization of the projections. It was discretized using a spectrum in energy, also called the spectrum of Herman. The results without correction for beam hardening showed significant differences in bone volume, which could lead to a possible diagnosis of osteoporosis. But the data with correction showed a decrease in bone volume, but this decrease was not significant in a confidence interval of 95%. (author)

  13. Beam hardening correction algorithm in microtomography images

    Energy Technology Data Exchange (ETDEWEB)

    Sales, Erika S.; Lima, Inaya C.B.; Lopes, Ricardo T., E-mail: esales@con.ufrj.b, E-mail: ricardo@lin.ufrj.b [Coordenacao dos Programas de Pos-graduacao de Engenharia (COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Lab. de Instrumentacao Nuclear; Assis, Joaquim T. de, E-mail: joaquim@iprj.uerj.b [Universidade do Estado do Rio de Janeiro (UERJ), Nova Friburgo, RJ (Brazil). Inst. Politecnico. Dept. de Engenharia Mecanica

    2009-07-01

    Quantification of mineral density of bone samples is directly related to the attenuation coefficient of bone. The X-rays used in microtomography images are polychromatic and have a moderately broad spectrum of energy, which makes the low-energy X-rays passing through a sample to be absorbed, causing a decrease in the attenuation coefficient and possibly artifacts. This decrease in the attenuation coefficient is due to a process called beam hardening. In this work the beam hardening of microtomography images of vertebrae of Wistar rats subjected to a study of hyperthyroidism was corrected by the method of linearization of the projections. It was discretized using a spectrum in energy, also called the spectrum of Herman. The results without correction for beam hardening showed significant differences in bone volume, which could lead to a possible diagnosis of osteoporosis. But the data with correction showed a decrease in bone volume, but this decrease was not significant in a confidence interval of 95%. (author)

  14. Devising Strain Hardening Models Using Kocks–Mecking Plots—A Comparison of Model Development for Titanium Aluminides and Case Hardening Steel

    Directory of Open Access Journals (Sweden)

    Markus Bambach

    2016-08-01

    Full Text Available The present study focuses on the development of strain hardening models taking into account the peculiarities of titanium aluminides. In comparison to steels, whose behavior has been studied extensively in the past, titanium aluminides possess a much larger initial work hardening rate, a sharp peak stress and pronounced softening. The work hardening behavior of a TNB-V4 (Ti–44.5Al–6.25Nb–0.8Mo–0.1B alloy is studied using isothermal hot compression tests conducted on a Gleeble 3500 simulator, and compared to the typical case hardening steel 25MoCrS4. The behavior is analyzed with the help of the Kocks-Mecking plots. In contrast to steel the TNB-V4 alloy shows a non-linear course of θ (i.e., no stage-III hardening initially and exhibits neither a plateau (stage IV hardening nor an inflection point at all deformation conditions. The present paper describes the development and application of a methodology for the design of strain hardening models for the TNB-V4 alloy and the 25CrMoS4 steel by taking the course of the Kocks-Mecking plots into account. Both models use different approaches for the hardening and softening mechanisms and accurately predict the flow stress over a wide range of deformation conditions. The methodology may hence assist in further developments of more sophisticated physically-based strain hardening models for TiAl-alloys.

  15. MANAGEMENT PROGRAMS ROAD REPAIR WORKS OF THE ROADS NETWORK

    Directory of Open Access Journals (Sweden)

    Вікторія Василівна ІГНАТЮК

    2015-05-01

    Full Text Available The paper discusses the model and algorithm optimization program of road repair works, with limited funds. Features introduction program for calculating rational level detection repair costs for the period of the program, which allows dos evolve a desired operating condition of the pavement.

  16. Radiation-hardenable diluents for radiation-hardenable compositions

    International Nuclear Information System (INIS)

    Schuster, K.E.; Rosenkranz, H.J.; Furh, K.; Ruedolph, H.

    1979-01-01

    Radiation-crosslinkable diluents for radiation-hardenable compositions (binders) consisting of a mixture of triacrylates of a reaction product of trimethylol propane and ethylene oxide with an average degree of ethoxylation of from 2.5 to 4 are described. The ethoxylated trimethylol propane is substantially free from trimethylol propane and has the following distribution: 4 to 5% by weight of monoethoxylation product, 14 to 16% by weight of diethoxylation product, 20 to 30% by weight of triethoxylation product, 20 to 30% by weight of tetraethoxylation product, 16 to 18% by weight of pentaethoxylation product, and 6 to 8% by weight of hexaethoxylation product. The diluents effectively reduce the viscosity of radiation-hardenable compositions and do not have any adverse effect upon their reactivity or upon the properties of the resulting hardened products

  17. Assessment and retrofit program at work

    Energy Technology Data Exchange (ETDEWEB)

    Schuyler, G [Rowan Williams Davies and Irwin Inc., Guelph, ON (Canada); Lethbridge, S [Owens-Corning, Guelph, ON (Canada)

    1993-10-01

    A glass plant in Ontario volunteered for an assessment as part of the Green Industry Assessment Retrofit Program. The project was intended to assess pollution prevention and reduction, water conservation, and energy utilization at the plant. The plant produces glass fibers and is a major user of natural gas and electricity, with a minimum electrical demand of 4 MW. Total waste heat in the flue gas from the gas-fired melting furnaces, relative to 25[degree]C, is over 5 MW. Nitrogen oxides are the predominant air emission at the plant. Glass fiber scrap constitutes the bulk of the solid wastes produced. Conservation opportunities were identified and their payback periods calculated. Options considered to be feasible included heat recovery and power generation from the furnace exhaust gases, and moving the air conditioning system intakes so they draw in cool air instead of hot air from the melter area. Bioremediation was considered to have good potential for treating the glass fiber wastes. Under this concept, the waste would be cycled through reactor cells containing microorganisms that could remove the binders and coatings on the fibers. At the end of this process, the glass fiber would be of sufficient quality that it could be recycled directly to the melter. 1 tab.

  18. Radiation-hardened CMOS integrated circuits

    International Nuclear Information System (INIS)

    Pikor, A.; Reiss, E.M.

    1980-01-01

    Substantial effort has been directed at radiation-hardening CMOS integrated circuits using various oxide processes. While most of these integrated circuits have been successful in demonstrating megarad hardness, further investigations have shown that the 'wet-oxide process' is most compatible with the RCA CD4000 Series process. This article describes advances in the wet-oxide process that have resulted in multimegarad hardness and yield to MIL-M-38510 screening requirements. The implementation of these advances into volume manufacturing is geared towards supplying devices for aerospace requirements such as the Defense Meterological Satellite program (DMSP) and the Global Positioning Satellite (GPS). (author)

  19. Work and Family Programs in Texas State Agencies.

    Science.gov (United States)

    Texas Work and Family Clearinghouse, Austin.

    A survey of work and family policies in state-supported organizations in Texas was conducted for the Texas Workforce Commission's Work and Family Clearinghouse. Survey questions addressed the prevalence, perceived need, and future direction of dependent care programs and flexible work arrangements (FWA). Key findings in dependent care include: (1)…

  20. 75 FR 9544 - Inmate Work and Performance Pay Program

    Science.gov (United States)

    2010-03-03

    ... inmate may receive performance pay only for that portion of the month that the inmate was working... Inmate Work and Performance Pay Program AGENCY: Bureau of Prisons, Justice. ACTION: Proposed rule... work and performance pay by removing redundant language and provisions that relate solely to staff...

  1. Determination of the strain hardening rate of metals and alloys by X ray diffraction

    International Nuclear Information System (INIS)

    Cadalbert, Robert

    1977-01-01

    This report for engineering graduation is based on the study of X ray diffraction line profile which varies with the plastic strain rate of the metal. After some generalities of strain hardening (consequence of a plastic deformation on the structure of a polycrystalline metal, means to study a strain hardened structure, use of X ray diffraction to analyse the strain hardened crystalline structure), the author reports the strain hardening rate measurement by using X ray diffraction. Several aspects are addressed: principles, experimental technique, apparatus, automation and programming of the measurement cycle, method sensitivity and precision. In the next part, the author reports applications: measurement of the strain hardening rate in different materials (tubes with hexagonal profile, cylindrical tubes in austenitic steel), and study of the evolution of strain hardening with temperature [fr

  2. Modification of Grange-Kiefer Approach for Determination of Hardenability in Eutectoid Steel

    Science.gov (United States)

    Sushanthi, Neethi; Maity, Joydeep

    2014-12-01

    In this research work, an independent mathematical modeling approach has been adopted for determination of the hardenability of steels. In this model, at first, cooling curves were generated by solving transient heat transfer equation through discretization with pure explicit finite difference scheme coupled with MATLAB-based programming considering variable thermo-physical properties of 1080 steel. Thereafter, a new fundamental approach is proposed for obtaining CCT noses as a function of volume fraction transformed through modification of Grange-Kiefer approach. The cooling curves were solved against 50 pct transformation nose of CCT diagram in order to predict hardening behavior of 1080 steel in terms of hardenability parameters (Grossmann critical diameter, D C; and ideal critical diameter, D I) and the variation of the unhardened core diameter ( D u) to diameter of steel bar ( D) ratio with diameter of the steel bar ( D). The experiments were also performed to ascertain actual D C value of 1080 steel for still water quenching. The D C value obtained by the developed model was found to match the experimental D C value with only 3 pct deviation. Therefore, the model developed in the present work can be used for direct determination of D I, D C and D u without resorting to any rigorous experimentation.

  3. Microstructural changes and strain hardening effects in abrasive contacts at different relative velocities and temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Rojacz, H., E-mail: rojacz@ac2t.at [AC2T research GmbH, Viktor-Kaplan-Straße 2C, 2700 Wiener Neustadt (Austria); Mozdzen, G. [Aerospace & Advanced Composites GmbH, Viktor-Kaplan-Straße 2F, 2700 Wiener Neustadt (Austria); Weigel, F.; Varga, M. [AC2T research GmbH, Viktor-Kaplan-Straße 2C, 2700 Wiener Neustadt (Austria)

    2016-08-15

    Strain hardening is commonly used to reach the full potential of materials and can be beneficial in tribological contacts. 2-body abrasive wear was simulated in a scratch test, aimed at strain hardening effects in various steels. Different working conditions were examined at various temperatures and velocities. Strain hardening effects and microstructural changes were analysed with high resolution scanning electron microscopy (HRSEM), electron backscatter diffraction (EBSD), micro hardness measurements and nanoindentation. Statistical analysing was performed quantifying the influence of different parameters on microstructures. Results show a crucial influence of temperature and velocity on the strain hardening in tribological contacts. Increased velocity leads to higher deformed microstructures and higher increased surface hardness at a lower depth of the deformed zones at all materials investigated. An optimised surface hardness can be achieved knowing the influence of velocity (strain rate) and temperature for a “tailor-made” surface hardening in tribological systems aimed at increased wear resistance. - Highlights: •Hardening mechanisms and their intensity in tribological contacts are dependent on relative velocity and temperature. •Beneficial surface hardened zones are formed at certain running-in conditions; the scientific background is presented here. •Ferritic-pearlitic steels strain hardens via grain size reduction and decreasing interlamellar distances in pearlite. •Austenitic steels show excellent surface hardening (120% hardness increase) by twinning and martensitic transformation. •Ferritic steels with hard phases harden in the ferrite phase as per Hall-Petch equation and degree of deformation.

  4. Microstructural changes and strain hardening effects in abrasive contacts at different relative velocities and temperatures

    International Nuclear Information System (INIS)

    Rojacz, H.; Mozdzen, G.; Weigel, F.; Varga, M.

    2016-01-01

    Strain hardening is commonly used to reach the full potential of materials and can be beneficial in tribological contacts. 2-body abrasive wear was simulated in a scratch test, aimed at strain hardening effects in various steels. Different working conditions were examined at various temperatures and velocities. Strain hardening effects and microstructural changes were analysed with high resolution scanning electron microscopy (HRSEM), electron backscatter diffraction (EBSD), micro hardness measurements and nanoindentation. Statistical analysing was performed quantifying the influence of different parameters on microstructures. Results show a crucial influence of temperature and velocity on the strain hardening in tribological contacts. Increased velocity leads to higher deformed microstructures and higher increased surface hardness at a lower depth of the deformed zones at all materials investigated. An optimised surface hardness can be achieved knowing the influence of velocity (strain rate) and temperature for a “tailor-made” surface hardening in tribological systems aimed at increased wear resistance. - Highlights: •Hardening mechanisms and their intensity in tribological contacts are dependent on relative velocity and temperature. •Beneficial surface hardened zones are formed at certain running-in conditions; the scientific background is presented here. •Ferritic-pearlitic steels strain hardens via grain size reduction and decreasing interlamellar distances in pearlite. •Austenitic steels show excellent surface hardening (120% hardness increase) by twinning and martensitic transformation. •Ferritic steels with hard phases harden in the ferrite phase as per Hall-Petch equation and degree of deformation.

  5. Understanding Teaching Development Programs - the why and how they work

    DEFF Research Database (Denmark)

    Rump, Camilla Østerberg; Christiansen, Frederik V; Trigwell, Keith

    impacts are reported, and the question of why and how the programs work is not addressed. This study is based on 79 participant projects and interviews with 19 teachers of which 9 also did one of the participant projects. The data was analyzed in relation to specific learning outcome and level, types......, SEBs and the institutional context, thereby providing insight into the why and how the program works and a basis for further development of the TDP....

  6. Influence of anisotropic hardening on longitudinal welding strains and stresses

    International Nuclear Information System (INIS)

    Gatovskij, K.M.; Revutskij, M.N.

    1981-01-01

    The algorithm and program for estimation of longitudinal welding strains and stresses with account of hardening and Bauschinger effect, which expand the possibilities of more complete description of stress change during thermodeformation welding cycles at bead surfacing on plate made of the 06Kh18N9T steel and AMg61 alloy. It is shown that for metals, deformation curves which are characterized by considerable yield moduli (Esub(T)/E>=0.05) hardening effect is considerable and its account leads to the decrease of stress level in the heataffected zone (down to 20%) [ru

  7. Numerical simulations of progressive hardening by using ABAQUS FEA software

    Directory of Open Access Journals (Sweden)

    Domański Tomasz

    2018-01-01

    Full Text Available The paper concerns numerical simulations of progressive hardening include phase transformations in solid state of steel. Abaqus FEA software is used for numerical analysis of temperature field and phase transformations. Numerical subroutines, written in fortran programming language are used in computer simulations where models of the distribution of movable heat source, kinetics of phase transformations in solid state as well as thermal and structural strain are implemented. Model for evaluation of fractions of phases and their kinetics is based on continuous heating diagram and continuous cooling diagram. The numerical analysis of thermal fields, phase fractions and strain associated progressive hardening of elements made of steel were done.

  8. Solution hardening and strain hardening at elevated temperatures

    International Nuclear Information System (INIS)

    Kocks, U.F.

    1982-10-01

    Solutes can significantly increase the rate of strain hardening; as a consequence, the saturation stress, at which strain hardening tends to cease for a given temperature and strain rate, is increased more than the yield stress: this is the major effect of solutes on strength at elevated temperatures, especially in the regime where dynamic strain-aging occurs. It is shown that local solute mobility can affect both the rate of dynamic recovery and the dislocation/dislocation interaction strength. The latter effect leads to multiplicative solution strengthening. It is explained by a new model based on repeated dislocation unlocking, in a high-temperature limit, which also rationalizes the stress dependence of static and dynamic strain-aging, and may help explain the plateau of the yield stress at elevated temperatures. 15 figures

  9. Workplace disability management programs promoting return-to-work

    DEFF Research Database (Denmark)

    Gensby, Ulrik; Lund, Thomas; Kowalski, Krystyna

    This report presents a Campbell systematic review on the effectiveness of workplace disability management programs (WPDM programs) promoting return to work (RTW), as implemented and practised by employers. The objectives of this review were to assess the effects of WPDM programs, to examine...... non-randomized studies (NRS) and eleven single group ‘before and after’ studies (B & A)), including data from eleven different WPDM programs, met the inclusion criteria. There were insufficient data on the characteristics of the sample and the effect sizes were uncertain. There is a lack of evidence...

  10. Tobacco training in clinical social work graduate programs.

    Science.gov (United States)

    Kleinfelder, JoAnn; Price, James H; Dake, Joseph A; Jordan, Timothy R; Price, Joy A

    2013-08-01

    The leading cause of preventable death, in the most vulnerable segments of society, whom social workers often counsel, is cigarette smoking. The purpose of this study was to assess tobacco smoking cessation training in clinical social work programs. A valid 21-item questionnaire was sent to the entire population of 189 clinical graduate social work programs identified by the Council on Social Work Education. A three-wave mailing process was used to maximize the return rate. Directors from 112 clinical social work programs returned completed questionnaires (61 percent). The majority (91 percent) of directors reported having never thought about offering formal smoking cessation training, and only nine of the programs (8 percent) currently provided formal smoking cessation education. The three leading barriers to offering smoking cessation education were as follows: not a priority (60 percent), not enough time (55 percent), and not required by the accrediting body (41 percent). These findings indicate that clinical social work students are not receiving standardized smoking cessation education to assist in improving the well-being of their clients. The national accrediting body for graduate clinical social work programs should consider implementing guidelines for smoking cessation training in the curriculums.

  11. BUSFET -- A radiation-hardened SOI transistor

    International Nuclear Information System (INIS)

    Schwank, J.R.; Shaneyfelt, M.R.; Draper, B.L.; Dodd, P.E.

    1999-01-01

    The total-dose hardness of SOI technology is limited by radiation-induced charge trapping in gate, field, and SOI buried oxides. Charge trapping in the buried oxide can lead to back-channel leakage and makes hardening SOI transistors more challenging than hardening bulk-silicon transistors. Two avenues for hardening the back-channel are (1) to use specially prepared SOI buried oxides that reduce the net amount of trapped positive charge or (2) to design transistors that are less sensitive to the effects of trapped charge in the buried oxide. In this work, the authors propose a partially-depleted SOI transistor structure for mitigating the effects of trapped charge in the buried oxide on radiation hardness. They call this structure the BUSFET--Body Under Source FET. The BUSFET utilizes a shallow source and a deep drain. As a result, the silicon depletion region at the back channel caused by radiation-induced charge trapping in the buried oxide does not form a conducting path between source and drain. Thus, the BUSFET structure design can significantly reduce radiation-induced back-channel leakage without using specially prepared buried oxides. Total dose hardness is achieved without degrading the intrinsic SEU or dose rate hardness of SOI technology. The effectiveness of the BUSFET structure for reducing total-dose back-channel leakage depends on several variables, including the top silicon film thickness and doping concentration, and the depth of the source. 3-D simulations show that for a body doping concentration of 10 18 cm -3 , a drain bias of 3 V, and a source depth of 90 nm, a silicon film thickness of 180 nm is sufficient to almost completely eliminate radiation-induced back-channel leakage. However, for a doping concentration of 3 x 10 17 cm -3 , a thicker silicon film (300 nm) must be used

  12. Radiation-hardened bulk CMOS technology

    International Nuclear Information System (INIS)

    Dawes, W.R. Jr.; Habing, D.H.

    1979-01-01

    The evolutionary development of a radiation-hardened bulk CMOS technology is reviewed. The metal gate hardened CMOS status is summarized, including both radiation and reliability data. The development of a radiation-hardened bulk silicon gate process which was successfully implemented to a commercial microprocessor family and applied to a new, radiation-hardened, LSI standard cell family is also discussed. The cell family is reviewed and preliminary characterization data is presented. Finally, a brief comparison of the various radiation-hardened technologies with regard to performance, reliability, and availability is made

  13. Anomalous precipitation hardening in Al-(1 wt%)Cu thin films

    NARCIS (Netherlands)

    Bergers, L. J. C.; De Hosson, J. Th. M.; Geers, M. G. D.; Hoefnagels, J. P. M.

    2018-01-01

    This paper concentrates on the precipitation hardening of Al-(1 wt%)Cu thin films. It is shown that in contrast to bulk, the well-known approach of precipitation hardening in confined systems like thin layers and thin films does not operate in the conventional way. This work analyses and discusses

  14. Toward Mentoring in Palliative Social Work: A Narrative Review of Mentoring Programs in Social Work.

    Science.gov (United States)

    Toh, Ying Pin; Karthik, R; Teo, Chia Chia; Suppiah, Sarasvathy; Cheung, Siew Li; Krishna, Lalit

    2018-03-01

    Mentoring by an experienced practitioner enhances professional well-being, promotes resilience, and provides a means of addressing poor job satisfaction and high burnout rates among medical social workers. This is a crucial source of support for social workers working in fields with high risk of compassion fatigue and burnout like palliative care. Implementing such a program, however, is hindered by differences in understanding and application of mentoring practice. This narrative review of mentoring practice in social work seeks to identify key elements and common approaches within successful mentoring programs in social work that could be adapted to guide the design of new mentoring programs in medical social work. Methodology and Data Sources: A literature search of mentoring programs in social work between January 1, 2000, and December 31, 2015, using Pubmed, CINAHL, OVID, ERIC, Scopus, Cochrane and ScienceDirect databases, involving a senior experienced mentor and undergraduate and/or junior postgraduates, was carried out. A total of 1302 abstracts were retrieved, 22 full-text articles were analyzed, and 8 articles were included. Thematic analysis of the included articles revealed 7 themes pertaining to the mentoring process, outcomes and barriers, and the characteristics of mentoring relationships, mentors, mentees, and host organizations. Common themes in prevailing mentoring practices help identify key elements for the design of an effective mentoring program in medical social work. We conclude with a discussion of the implications of these findings upon clinical practice in palliative care and on sustaining such a program.

  15. Computer modelling of age hardening for cast aluminium alloys

    International Nuclear Information System (INIS)

    Wu, Linda; Ferguson, W George

    2009-01-01

    Age hardening, or precipitation hardening, is one of the most widely adopted techniques for strengthening of aluminium alloys. Although various age hardening models have been developed for aluminium alloys, from the large volume of literature reviewed, it appears that the bulk of the research has been concentrated on wrought aluminium alloys, only a few of the established precipitation models have been applied to the casting aluminium alloys. In the present work, there are two modelling methods that have been developed and applied to the casting aluminium alloys A356 and A357. One is based on the Shercliff-Ashby methodology to produce a process model, by which we mean a mathematical relationship between process variables (alloy composition, ageing temperature and time) and material properties (yield strength or hardness) through microstructure evolution (precipitate radius, volume fraction). The other method is based on the Kampmann and Wagner Numerical (KWN) model which deals with concomitant nucleation, growth and coarsening and is thus capable of predicting the full evolution of the particle size distribution and then a strength model is used to evaluate the resulting change in hardness or yield strength at room temperature by taking into account contributions from lattice resistance, solid solution hardening and precipitation hardening.

  16. Characterizing and Mitigating Work Time Inflation in Task Parallel Programs

    Directory of Open Access Journals (Sweden)

    Stephen L. Olivier

    2013-01-01

    Full Text Available Task parallelism raises the level of abstraction in shared memory parallel programming to simplify the development of complex applications. However, task parallel applications can exhibit poor performance due to thread idleness, scheduling overheads, and work time inflation – additional time spent by threads in a multithreaded computation beyond the time required to perform the same work in a sequential computation. We identify the contributions of each factor to lost efficiency in various task parallel OpenMP applications and diagnose the causes of work time inflation in those applications. Increased data access latency can cause significant work time inflation in NUMA systems. Our locality framework for task parallel OpenMP programs mitigates this cause of work time inflation. Our extensions to the Qthreads library demonstrate that locality-aware scheduling can improve performance up to 3X compared to the Intel OpenMP task scheduler.

  17. Superheat effect on bainite steel hardenability

    International Nuclear Information System (INIS)

    Kubachek, V.V.; Sklyuev, P.V.

    1978-01-01

    The bainite hardenability of 34KhN1M and 35 KhN1M2Ph steels has been investigated by the end-face hardening technique. It is established that, as the temperature of austenitization rises from 900 to 1280 deg C, the temperature of bainite transformation increases and bainite hardenability of the steels falls off. A repeated slow heating to 900 deg C of previously overheated 34KhN1M steel breaks up grain, lowers the temperature of the bainite transformation and raises the hardenability to values obtained with ordinary hardening from 900 deg C. A similar heating of previously overheated 35KhN1M2Ph steel is accompanied by restoration of initial coarse grains and maintenance of both the elevated bainite transformation temperature and to lower hardenability corresponding to hardening from the temperature of previous overheating

  18. A non-linear kinematic hardening function

    International Nuclear Information System (INIS)

    Ottosen, N.S.

    1977-05-01

    Based on the classical theory of plasticity, and accepting the von Mises criterion as the initial yield criterion, a non-linear kinematic hardening function applicable both to Melan-Prager's and to Ziegler's hardening rule is proposed. This non-linear hardening function is determined by means of the uniaxial stress-strain curve, and any such curve is applicable. The proposed hardening function considers the problem of general reversed loading, and a smooth change in the behaviour from one plastic state to another nearlying plastic state is obtained. A review of both the kinematic hardening theory and the corresponding non-linear hardening assumptions is given, and it is shown that material behaviour is identical whether Melan-Prager's or Ziegler's hardening rule is applied, provided that the von Mises yield criterion is adopted. (author)

  19. Scintillation-Hardened GPS Receiver

    Science.gov (United States)

    Stephens, Donald R.

    2015-01-01

    CommLargo, Inc., has developed a scintillation-hardened Global Positioning System (GPS) receiver that improves reliability for low-orbit missions and complies with NASA's Space Telecommunications Radio System (STRS) architecture standards. A software-defined radio (SDR) implementation allows a single hardware element to function as either a conventional radio or as a GPS receiver, providing backup and redundancy for platforms such as the International Space Station (ISS) and high-value remote sensing platforms. The innovation's flexible SDR implementation reduces cost, weight, and power requirements. Scintillation hardening improves mission reliability and variability. In Phase I, CommLargo refactored an open-source GPS software package with Kalman filter-based tracking loops to improve performance during scintillation and also demonstrated improved navigation during a geomagnetic storm. In Phase II, the company generated a new field-programmable gate array (FPGA)-based GPS waveform to demonstrate on NASA's Space Communication and Navigation (SCaN) test bed.

  20. Radiation-hardened control system

    International Nuclear Information System (INIS)

    Vandermolen, R.I.; Smith, S.F.; Emery, M.S.

    1993-01-01

    A radiation-hardened bit-slice control system with associated input/output circuits was developed to prove that programmable circuits could be constructed to successfully implement intelligent functions in a highly radioactive environment. The goal for this effort was to design and test a programmable control system that could withstand a minimum total dose of 10 7 rads (gamma). The Radiation Hardened Control System (RHCS) was tested in operation at a dose rate that ranged up to 135 krad/h, with an average total dose of 10.75 Mrads. Further testing beyond the required 10 7 rads was also conducted. RHCS performed properly through the target dose of 10 7 rads, and sporadic intermittent failures in some programmable logic devices were noted after ∼ 13 Mrads

  1. Collaboration for cooperative work experience programs in biomedical engineering education.

    Science.gov (United States)

    Krishnan, Shankar

    2010-01-01

    Incorporating cooperative education modules as a segment of the undergraduate educational program is aimed to assist students in gaining real-life experience in the field of their choice. The cooperative work modules facilitate the students in exploring different realistic aspects of work processes in the field. The track records for cooperative learning modules are very positive. However, it is indeed a challenge for the faculty developing Biomedical Engineering (BME) curriculum to include cooperative work experience or internship requirements coupled with a heavy course load through the entire program. The objective of the present work is to develop a scheme for collaborative co-op work experience for the undergraduate training in the fast-growing BME programs. A few co-op/internship models are developed for the students pursuing undergraduate BME degree. The salient features of one co-op model are described. The results obtained support the proposed scheme. In conclusion, the cooperative work experience will be an invaluable segment in biomedical engineering education and an appropriate model has to be selected to blend with the overall training program.

  2. Exploration of a radiation hardening stabilized voltage power supply

    International Nuclear Information System (INIS)

    Xie Zeyuan; Xu Xianguo

    2014-01-01

    This paper mainly introduces the design method of radiation hardening stabilized voltage power supply that makes use of commercial radiation resistant electronic devices and the test results of radiation performance of the power supply and devices are presented in detail. The experiment results show that the hardened power supply can normally work until 1000 Gy (Si) total dose and 1 × 10 14 n/cm 2 neutron radiation, and it doesn't latchup at about 1 × l0 9 Gy (Si)/s gamma transient dose rate. (authors)

  3. Harwell hardens Staeubli Puma

    International Nuclear Information System (INIS)

    Watson, C.J.H.

    1992-01-01

    The Remote Handling and Robotics Department at Harwell, has argued that it ought to be possible to combine all the advantages of the industrial robot - its off-the-shelf availability, low cost and high reliability - with the specific requirements of the nuclear industry, by subjecting an industrial robot to a programme of ''nuclear engineering''. After a careful evaluation, they selected the Staubli Unimation Puma 760 robot as the first candidate for this programme. Three years, and several Pound 100,000s later, they have launched on the market the world's first Nuclear Engineered Advanced Telerobot, or NEATER, as it is called. The device is manufactured by Staubli Unimation, to the same mechanical and QA standards as a standard PUMA, but with all the non-metallic components replaced by radiation tolerant materials. These were chosen by Harwell, after extensive radiation testing and design work, to ensure that the whole robot can tolerate up to 100 MRads - i.e. the highest radiation dose that a robot is likely to experience in a normal nuclear facility. It is controlled, like a normal PUMA, by a VAL 2 industrial robot controller, but this is ''front-ended'' by the Harwell Telerobotic Controller, a PC-based controller, which takes human commands from mechanical ''Input Device'' and translates these into VAL commands, which can then be interpreted by the VAL 2 controller in the normal way. (Author)

  4. Return to work programs are becoming a business priority

    Energy Technology Data Exchange (ETDEWEB)

    Anon

    2001-06-01

    Improved safety planning and operational procedures in the offshore industry, based on lessons learned from accidents offshore, are discussed. The emphasis in this instance is on the 'return-to-work' (RTW) program which consists of a formal set of processes whose goal is to minimize the impact of an impairment or disability on an individual's capacity to work. The program is designed to assist workers to return to their jobs or to an alternate suitable job, to mitigate the human and financial cost for both the worker and the employer. RTW programs are said to have assumed greater importance recently because of globalization of the economy and downsizing, and the increased pressure on organizations to decrease costs to stay competitive. The longer work-week for the remaining employees and increase in the average age of the workforce which tend to increase recovery time from an injury, are other factors contributing to the demand for increased safety in the work place and the increased popularity of structured and regulated return-to-work programs in all sectors of industry. Retained seniority, pay and benefits, along with maintaining self-worth, family stability, and social ties, are suggested as the principal benefit to workers. Employers would benefit from the ability to retain skilled workers, minimize production losses, and minimize the need to recruit and train new workers, or to retrain current employees to perform new tasks. To be successful, the employer must commit money and resources for the program, and employees have to be fully aware of the benefits of an RTW program. It appears that pending legislation making workplace accommodation mandatory, an RTW program will soon become a business essential for employers. At the same time, rising health care costs provide further substantiation for more structured approaches to reduce claims and absenteeism from the workplace.

  5. Work Life Balance Programs at Workplaces in the US (Japanese)

    OpenAIRE

    KUROSAWA Masako

    2011-01-01

    With the very limited policy intervention, work-life balance (WLB) enhancing programs available at workplaces in the US are not as prevalent as those observed in most continental European countries. Nevertheless, starting in the late 80s, firms began to introduce WLB enhancing programs, mostly in terms of flexible schedules, as ways to help workers and improve firm performance. The availability of workplace flexibility, however, has been mostly limited to highly skilled workers. This paper sh...

  6. Effect of yield strength on stress corrosion crack propagation under PWR and BWR environments of hardened stainless steels

    Energy Technology Data Exchange (ETDEWEB)

    Castano, M.L.; Garcia, M.S.; Diego, G. de; Gomez-Briceno, D. [CIEMAT, Nuclear Fission Department, Structural Materials Program, Avda. Complutense 22, 28040 Madrid (Spain)

    2004-07-01

    stress corrosion cracking of austenitic stainless steels (SS) and to quantify the effect on the crack propagation rate, an experimental research program was performed using cold and warm worked 304, 316L and 347 SS. Stress corrosion crack growth rate tests, under BWR and PWR environments have been carried out. The results obtained have permitted to determine the yield strength effect in the crack propagation of austenitic stainless steels in PWR and BWR conditions. In addition, similarities on cold work and radiation hardening in enhancing the yield strength and the stress corrosion cracking propagation at high temperature water have been evaluated. (authors)

  7. Workplace disability management programs promoting return-to-work

    DEFF Research Database (Denmark)

    Gensby, Ulrik; Lund, Thomas; Kowalski, Krystyna

    Return-to-work (RTW) following work related injuries or illnesses is receiving continued attention from a wide spectrum of research fields and is an important topic for many policy- and decision-makers. In particular long-term sickness absence is a challenge associated with a series of negative...... is still needed. This review will evaluate the effect of workplace disability management programs promoting RTW - i.e. report on the evidence and describes and combine results from individual studies on workplace disability management programs and explain possible variations in practice....

  8. New Mexico district work-effort analysis computer program

    Science.gov (United States)

    Hiss, W.L.; Trantolo, A.P.; Sparks, J.L.

    1972-01-01

    The computer program (CAN 2) described in this report is one of several related programs used in the New Mexico District cost-analysis system. The work-effort information used in these programs is accumulated and entered to the nearest hour on forms completed by each employee. Tabulating cards are punched directly from these forms after visual examinations for errors are made. Reports containing detailed work-effort data itemized by employee within each project and account and by account and project for each employee are prepared for both current-month and year-to-date periods by the CAN 2 computer program. An option allowing preparation of reports for a specified 3-month period is provided. The total number of hours worked on each account and project and a grand total of hours worked in the New Mexico District is computed and presented in a summary report for each period. Work effort not chargeable directly to individual projects or accounts is considered as overhead and can be apportioned to the individual accounts and projects on the basis of the ratio of the total hours of work effort for the individual accounts or projects to the total New Mexico District work effort at the option of the user. The hours of work performed by a particular section, such as General Investigations or Surface Water, are prorated and charged to the projects or accounts within the particular section. A number of surveillance or buffer accounts are employed to account for the hours worked on special events or on those parts of large projects or accounts that require a more detailed analysis. Any part of the New Mexico District operation can be separated and analyzed in detail by establishing an appropriate buffer account. With the exception of statements associated with word size, the computer program is written in FORTRAN IV in a relatively low and standard language level to facilitate its use on different digital computers. The program has been run only on a Control Data Corporation

  9. Study on mechanism of intergranular stress corrosion cracking and analysis of residual stress and work hardening in welds of low-carbon austenitic stainless steel with hard surface machining

    International Nuclear Information System (INIS)

    Mori, Hiroaki; Mochizuki, Masahito; Nishimoto, Kazutoshi; Toyoda, Masao; Katsuyama, Jinya

    2007-01-01

    In order to make clear the effects of residual stress and hardening on intergranular stress corrosion cracking (IGSCC) behavior in the welds of Type 316L low-carbon austenitic stainless steel with surface hardening, the residual stress and hardness in the butt-joint of pipes as a typical example of the actual structure were estimated and the grain boundary sliding was analyzed from the viewpoint of micro-deformation. On the basis of these results, the mechanism of IGSCC was discussed by the integrated knowledge between metallurgy and mechanics. The relationship between plastic strain and hardness in hard-machined surface near welds was clarified from the experimented relationship and the analysis method by the thermal elastic-plastic analysis. The distributions of hardness and residual stress with the actual surface machining could be simulated. It was made clear that grain boundary sliding occurred in the steel at 561K by a constant strain rate tensile test. From the comparison of grain boundary sliding behavior between solution treated specimen and cold-rolled one, it was found that the grain boundary sliding in cold-rolled one occurs in smaller strain conditions than that in as received one, and the amount of grain boundary sliding in cold-rolled one increases remarkably with increases in rolling reduction. In addition, it was clarified that the grain boundary energy is raised by the grain boundary sliding. On the basis of these results, it was concluded that the cause of IGSCC in the welds of Type 316L low-carbon austenitic stainless steel with surface hardening is the increase in grain boundary energy due to grain boundary sliding induced by residual stress of multi pass welding and surface hardening. (author)

  10. 40 CFR 256.05 - Annual work program.

    Science.gov (United States)

    2010-07-01

    ... FOR DEVELOPMENT AND IMPLEMENTATION OF STATE SOLID WASTE MANAGEMENT PLANS Purpose, General Requirements... included by reference in the annual work program: (1) Substate solid waste management plans, (2) Plans for the development of facilities and services, including hazardous waste management facilities and...

  11. Knowledge Is Power Program (KIPP). What Works Clearinghouse Intervention Report

    Science.gov (United States)

    What Works Clearinghouse, 2018

    2018-01-01

    The "Knowledge Is Power Program" ("KIPP") is a nonprofit network of more than 200 public charter schools educating early childhood, elementary, middle, and high school students. The What Works Clearinghouse (WWC) identified four studies of "KIPP" that fall within the scope of the Charter Schools topic area and meet…

  12. Compile-Time Debugging of C Programs Working on Trees

    DEFF Research Database (Denmark)

    Elgaard, Jacob; Møller, Anders; Schwartzbach, Michael I.

    2000-01-01

    of an initial store that leads to an error is automatically generated. This extends previous work that uses a similar technique to verify a simpler syntax manipulating only list structures. In that case, programs are translated into WS1S formulas. A naive generalization to recursive data-types determines...

  13. 40 CFR 1048.405 - How does this program work?

    Science.gov (United States)

    2010-07-01

    ... Section 1048.405 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF EMISSIONS FROM NEW, LARGE NONROAD SPARK-IGNITION ENGINES Testing In-use Engines § 1048.405 How does this program work? (a) You must test in-use engines, for exhaust emissions, from the...

  14. NASA Pathways: Intern Employment Program Work Report Summer 2014

    Science.gov (United States)

    Davidson, Kyle B.

    2014-01-01

    This report documents the work experience and project involvement of Kyle Davidson during his tenure at Kennedy Space Center for the summer of 2014. Projects include the Nitrogen Oxygen Recharge System (NORS), Restore satellite servicing program, and mechanical handling operations for the SAGE III and Rapidscat payloads.

  15. Research on SEU hardening of heterogeneous Dual-Core SoC

    Science.gov (United States)

    Huang, Kun; Hu, Keliu; Deng, Jun; Zhang, Tao

    2017-08-01

    The implementation of Single-Event Upsets (SEU) hardening has various schemes. However, some of them require a lot of human, material and financial resources. This paper proposes an easy scheme on SEU hardening for Heterogeneous Dual-core SoC (HD SoC) which contains three techniques. First, the automatic Triple Modular Redundancy (TMR) technique is adopted to harden the register heaps of the processor and the instruction-fetching module. Second, Hamming codes are used to harden the random access memory (RAM). Last, a software signature technique is applied to check the programs which are running on CPU. The scheme need not to consume additional resources, and has little influence on the performance of CPU. These technologies are very mature, easy to implement and needs low cost. According to the simulation result, the scheme can satisfy the basic demand of SEU-hardening.

  16. Worker programs and resource use: Evidence from better work jordan

    Science.gov (United States)

    Robins, Nathan

    This paper examines data collected for the Better Work program in Jordan which aims to protect laborers in the garment industry from poor working conditions. Data are examined to look for benefits to the factories participating in the program beyond improved compliance with labor law. In particular, potential impacts to firm energy use are examined and correlations are tested between electricity use rates and measures of worker outcomes and a number of factory traits such as size and production input costs. Evidence was found to back up work done in Vietnam with regard to resource use and distribution of electricity expenses. It was also found that the type of data being collected is not ideal for examinations of energy, and more direct methods are desirable, and that considerable production obstacles are worker skill level, electricity prices, and to a greater degree in Jordan than in previously examined countries, water prices.

  17. Developing optimal nurses work schedule using integer programming

    Science.gov (United States)

    Shahidin, Ainon Mardhiyah; Said, Mohd Syazwan Md; Said, Noor Hizwan Mohamad; Sazali, Noor Izatie Amaliena

    2017-08-01

    Time management is the art of arranging, organizing and scheduling one's time for the purpose of generating more effective work and productivity. Scheduling is the process of deciding how to commit resources between varieties of possible tasks. Thus, it is crucial for every organization to have a good work schedule for their staffs. The job of Ward nurses at hospitals runs for 24 hours every day. Therefore, nurses will be working using shift scheduling. This study is aimed to solve the nurse scheduling problem at an emergency ward of a private hospital. A 7-day work schedule for 7 consecutive weeks satisfying all the constraints set by the hospital will be developed using Integer Programming. The work schedule for the nurses obtained gives an optimal solution where all the constraints are being satisfied successfully.

  18. Environmental Restoration Remedial Actions Program Field Office Work Plan

    International Nuclear Information System (INIS)

    1989-02-01

    The Environmental Restoration Remedial Actions (ERRA) Program was established by DP to comply with regulations for characterization and cleanup of inactive waste sites. The program specifically includes inactive site identification and characterization, technology development and demonstration, remedial design and cleanup action, and postclosure activities of inactive radioactive, chemically hazardous, and mixed waste sites. It does not include facility decontamination and decommissioning activities; these are included in a parallel program, Environmental Restoration Decontamination and Decommissioning (ERD and D), also managed by DP. The ERRA program was formally established in fiscal year (FY) 1988 at the Hanford Site to characterize and remediate inactive waste sites at Hanford. The objectives, planned implementation activities, and management planning for the ERRA Program are contained in several planning documents. These documents include planning for the national program and for the Hanford Program. This summary describes the major documents and the role and purpose of this Field Office Work Plan (FOWP) within the overall hierarchy of planning documents. 4 refs., 7 figs., 8 tabs

  19. A Novel Radiation Hardened CAM

    CERN Document Server

    Shojaii, Seyed Ruhollah; The ATLAS collaboration

    2018-01-01

    This poster describes an innovative Content Addressable Memory cell with radiation hardened (RH-CAM) architecture. The RH-CAM is designed in a commercial 28 nm CMOS technology. The circuit has been simulated in worst-case conditions, and the effects due to single particles are analyzed injecting a fault current into a circuit node. The proposed architecture can perform on-time pattern recognition tasks in harsh environments, such as very front-end electronics in hadron colliders and in space applications.

  20. Optimization of resistively hardened latches

    International Nuclear Information System (INIS)

    Gagne, G.; Savaria, Y.

    1990-01-01

    The design of digital circuits tolerant to single-event upsets is considered. The results of a study are presented on which an analytical model was used to predict the behavior of a standard resistively hardened latch. It is shown that a worst case analysis for all possible single-event upset situations (on the latch or in the logic) can be derived from studying the effects of a transient disturbed write cycle. The existence of an intrinsic minimum write period to tolerate a transient of a given duration is also demonstrated

  1. Instabilities in power law gradient hardening materials

    DEFF Research Database (Denmark)

    Niordson, Christian Frithiof; Tvergaard, Viggo

    2005-01-01

    Tension and compression instabilities are investigated for specimens with dimensions in the micron range. A finite strain generalization of a higher order strain gradient plasticity theory is implemented in a finite element scheme capable of modeling power law hardening materials. Effects...... of gradient hardening are found to delay the onset of localization under plane strain tension, and significantly reduce strain gradients in the localized zone. For plane strain compression gradient hardening is found to increase the load-carrying capacity significantly....

  2. Influence of Cooling Condition on the Performance of Grinding Hardened Layer in Grind-hardening

    Science.gov (United States)

    Wang, G. C.; Chen, J.; Xu, G. Y.; Li, X.

    2018-02-01

    45# steel was grinded and hardened on a surface grinding machine to study the effect of three different cooling media, including emulsion, dry air and liquid nitrogen, on the microstructure and properties of the hardened layer. The results show that the microstructure of material surface hardened with emulsion is pearlite and no hardened layer. The surface roughness is small and the residual stress is compressive stress. With cooling condition of liquid nitrogen and dry air, the specimen surface are hardened, the organization is martensite, the surface roughness is also not changed, but high hardness of hardened layer and surface compressive stress were obtained when grinding using liquid nitrogen. The deeper hardened layer grinded with dry air was obtained and surface residual stress is tensile stress. This study provides an experimental basis for choosing the appropriate cooling mode to effectively control the performance of grinding hardened layer.

  3. Work engagement in employees at professional improvement programs in health

    Directory of Open Access Journals (Sweden)

    Elizangela Gianini Gonsalez

    2017-09-01

    Full Text Available Objective: This study evaluated the levels of engagement at work in enhancement programs and professionals training in health. Method: A cross-sectional study with 82 health professionals enhancement programs and improvement of a public institution in the State of São Paulo, using the Utrech Work Engagement Scale (UWES, a self-administered questionnaire composed of seventeen self-assessment items in three dimensions: vigor, dedication and absorption. The scores were calculated according to the statistical model proposed in the Preliminary Manual UWES. Results: Engagement levels were too high on the force, high dedication and dimension in general score, and medium in size to 71.61% absorption, 58.03%, 53.75% and 51.22% of workers, respectively. The professionals present positive relationship with the work; they are responsible, motivated and dedicated to the job and to the patients. Conclusion: Reinforces the importance of studies that evaluate positive aspects of the relationship between professionals and working environment, contributing to strengthen the programs of improvement, advancing the profile of professionals into the labour market.

  4. Hanford Site Environmental Restoration Program 1994 fiscal year work plan

    International Nuclear Information System (INIS)

    1993-01-01

    Site Management System (SMS) guidance requires a Fiscal Year Work Plan (FYWP) to be prepared for the Environmental Restoration (ER) Mission Area and all related programs. This revision is a complete update to cover the FY 1994 time period. This document describes the overall ER Missions Area and provides FYWP appendices for each of the following five program areas: Remedial Action (RA); Decontamination and Decommissioning (D ampersand D); Project Management and Support (PM ampersand S); Surveillance and Maintenance (S ampersand M); and Disposal Facilities (DF)

  5. Evaluation of hardening by ion irradiation in molybdenum using nanoindentation techniques

    International Nuclear Information System (INIS)

    Iwakiri, Hirotomi; Watanabe, Hideo; Yoshida, Naoaki

    1997-01-01

    As a part of fundamental research on interaction of plasma and wall, some model experiments on loading of particles such as He, H and so forth suffered by plasma facing material were conducted for Mo in high Z material. As an evaluation method for it, nanoindentation technique was proposed. By this method, the hardness evaluation in surface neighboring damage range was conducted. As a result, in the helium irradiated materials, sufficient hardening was observed even at low dpa range impossible to recognize hardening on heavy ion and deuterium irradiated materials, and extreme hardening was established by formation of helium bubble at high dpa region. Furthermore, in the helium irradiated materials, recovery of hardening could not be observed even for annealed materials at 1173 K for 1 hr after irradiation. From such results, hardening promotion work due to helium and extreme thermal stability of the formed defects were elucidated. (B.K.)

  6. Development of Bake Hardening Effect by Plastic Deformation and Annealing Conditions

    Directory of Open Access Journals (Sweden)

    Kvačkaj, T.

    2006-01-01

    Full Text Available The paper deals with the classification of steel sheets for automotives industry on the basis of strength and structural characteristics. Experimental works were aimed to obtain the best possible strengthening parameters as well as work hardening and solid solution ferrite hardening, which are the result of thermal activation of interstitial carbon atoms during paint-baking of auto body. Hardening process coming from interstitial atoms is realized as two-step process. The first step is BH (bake hardening effect achieved by interaction of interstitial atoms with dislocations. The Cottrels atmosphere is obtained. The second step of BH effect is to produced the hardening from precipitation of the carbon atoms in e-carbides, or formation of Fe32C4 carbides. WH (work hardening effect is obtained as dislocation hardening from plastic deformations during sheet deep drawing. Experimental works were aimed at as to achieve such plastic material properties after cold rolling, annealing and skin-pass rolling, which would be able to classify the material ZStE220BH into the drawing categories at the level of DQ – DDQ. As resulting from the experimental results, the optimal treatment conditions for the maximal sum (WH+BH = 86 MPa are as follows: total cold rolling deformation ecold = 65 %, annealing temperature Tanneal. = 700 °C.

  7. Now Enhancing Working Skills: The ``NEWS`` Program. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Kuiper, A. [Merex Corp. (United States)

    1995-01-23

    In October of 1992, Los Alamos National Laboratory and Merex Corporation began a pilot basic skills program to enhance workers` skills. The program, known as the NEWS (Now Enhancing Working Skills) Program, was implemented by the Training and Development Group of the Human Resources Division. A group of 106 employees known as Radiological Control Technicians (RCTs) from ESH-1 (Environmental, Safety, and Health) were targeted to take mandated DOE (Department of Energy) training. The main goal of the LANL/Merex partnership was to help RCTs prepare for mandated DOE Rad Con training and job performance by improving their information processing and math skills. A second goal of this project was to use the information from this small group to make some predictions about the Laboratory as a whole. This final report contains the description and an appendix for the ``NEWS`` program. The topics in this report include Merex class descriptions, test score results for the MAT, the WAT, the TABE, and Challenge test, a follow-up survey to Merex IPS and math training, student feedback statistics for skills programs, and lessons learned from the program.

  8. Team Work in International Programs: Why is it so difficult?

    DEFF Research Database (Denmark)

    Lauridsen, Karen M.; Madsen, Henning

    intercultural collaboration. The issues that arise seem to be grounded in linguistic, cultural and educational factors. This paper reports on and discusses a study of student responses to intercultural collaboration (in English) in two programmes at Aarhus University, Denmark. One conclusion...... is that the international students are more prepared to work in multicultural teams than their Danish peers. Another one tells us that once students have experience with the diversity of these teams, at least some of them become more open towards working in such teams in the future. It is interesting to discuss......Team Work in International Programs: Why is it so difficult? And what can we do about it? It is common knowledge that students often find it difficult to collaborate on assignments, projects, etc., but we require that they do so for a number of reasons, e.g. to learn how to work in teams or take...

  9. Work program. Borehole PPG-1 and seismical velocity profile

    International Nuclear Information System (INIS)

    1987-08-01

    The topic of this report is to give the detailed work program of the foreseen drillings and to describe the investigations and measurements connected with it. It is based on the results of the advertisements and commission's negotiations as well as on the discussions with cantonal and communal authorities. The aim of the work is primarily the judgement of the geological and hydrogeological forecasts which have led to the choice of the area Piz Pian Grand as a potential site. 5 figs., 1 tab

  10. Modelling the work flow of a nuclear waste management program

    Energy Technology Data Exchange (ETDEWEB)

    Hoeyer Mortensen, K. [Aarhus Univ., Computer Science Dept. (Denmark); Pinci, V. [Meta Software Corporation, Cambridge, MA (United States)

    1997-03-01

    In this paper we describe a modelling project to improve a nuclear waste management program in charge of the creation of a new system for the permanent disposal of nuclear waste. SADT (Structural Analysis and Design Technique) is used in order to provide a work-flow description of the functions to be performed by the waste management program. This description is then translated into a number of Coloured Petri Nets (CPN or CP-nets) corresponding to different program functions where additional behavioural inscriptions provide basis for simulation. Each of these CP-nets is simulated to produce timed event charts that are useful for understanding the behaviour of the program functions under different scenarios. Then all the CPN models are linked together to form a single stand-alone application that is useful for validating the interaction and cooperation between the different program functions. A technique for linking executable CPN models is developed for supporting large modelling projects and parallel development of independent CPN models. (au) 11 refs.

  11. Modelling the work flow of a nuclear waste management program

    International Nuclear Information System (INIS)

    Hoeyer Mortensen, K.; Pinci, V.

    1997-03-01

    In this paper we describe a modelling project to improve a nuclear waste management program in charge of the creation of a new system for the permanent disposal of nuclear waste. SADT (Structural Analysis and Design Technique) is used in order to provide a work-flow description of the functions to be performed by the waste management program. This description is then translated into a number of Coloured Petri Nets (CPN or CP-nets) corresponding to different program functions where additional behavioural inscriptions provide basis for simulation. Each of these CP-nets is simulated to produce timed event charts that are useful for understanding the behaviour of the program functions under different scenarios. Then all the CPN models are linked together to form a single stand-alone application that is useful for validating the interaction and cooperation between the different program functions. A technique for linking executable CPN models is developed for supporting large modelling projects and parallel development of independent CPN models. (au) 11 refs

  12. Dual Degree Social Work Programs: Where are the Programs and Where are the Graduates?

    Directory of Open Access Journals (Sweden)

    Shari E. Miller

    2008-09-01

    Full Text Available This article presents results of an exploratory study designed to survey the dual degree graduates of one large school of social work, and to report on the prevalence and types of dual degree programs offered at accredited schools of social work in the U.S. Quantitative and qualitative data were gathered from 72 dual degree graduates. Income, career trajectories, identification with social work, satisfaction with the decision to obtain a dual degree, whether graduates would encourage others to follow the dual degree path, and implications for the social work profession and social work education are discussed.

  13. Salt repository sealing materials development program: 5-year work plan

    International Nuclear Information System (INIS)

    Myers, L.B.

    1986-06-01

    This plan covers 5 years (fiscal years 1986 through 1990) of work in the repository sealing materials program to support design decisions and licensing activities for a salt repository. The plan covers a development activity, not a research activity. There are firm deliverables as the end points of each part of the work. The major deliverables are: development plans for code development and materials testing; seal system components models; seal system performance specifications; seal materials specifications; and seal materials properties ''handbook.'' The work described in this plan is divided into three general tasks as follows: mathematical modeling; materials studies (salt, cementitious materials, and earthen materials); and large-scale testing. Each of the sections presents an overview, status, planned activities, and summary of program milestones. This plan will be the starting point for preparing the development plans described above, but is subject to change if preparation of the work plan indicates that a different approach or sequence is preferable to achieve the ultimate goal, i.e., support of design and licensing

  14. Hardening of niobium alloys at precrystallization annealing

    International Nuclear Information System (INIS)

    Vasil'eva, E.V.; Pustovalov, V.A.

    1989-01-01

    Niobium base alloys were investigated. It is shown that precrystallization annealing of niobium-molybdenum, niobium-vanadium and niobium-zirconium alloys elevates much more sufficiently their resistance to microplastic strains, than to macroplastic strains. Hardening effect differs sufficiently for different alloys. The maximal hardening is observed for niobium-vanadium alloys, the minimal one - for niobium-zirconium alloys

  15. Investigation of a Hardened Cement Paste Grout

    DEFF Research Database (Denmark)

    Esteves, Luis Pedro; Sørensen, Eigil Verner

    This report documents a series of tests performed on a hardened cement paste grout delivered by the client, Det Norske Veritas A/S.......This report documents a series of tests performed on a hardened cement paste grout delivered by the client, Det Norske Veritas A/S....

  16. Radiation hardening of integrated circuits technologies

    International Nuclear Information System (INIS)

    Auberton-Herve, A.J.; Leray, J.L.

    1991-01-01

    The radiation hardening studies started in the mid decade -1960-1970. To survive the different military or space radiative environment, a new engineering science borned, to understand the degradation of electronics components. The different solutions to improve the electronic behavior in such environment, have been named radiation hardening of the technologies. Improvement of existing technologies, and qualification method have been widely studied. However, at the other hand, specific technologies was developped : The Silicon On Insulator technologies for CMOS or Bipolar. The HSOI3HD technology (supported by DGA-CEA DAM and LETI with THOMSON TMS) offers today the highest hardening level for the integration density of hundreds of thousand transistors on the same silicon. Full complex systems would be realized on a single die with a technological radiation hardening and no more system hardening

  17. Challenges in hardening technologies using shallow-trench isolation

    International Nuclear Information System (INIS)

    Shaneyfelt, M.R.; Dodd, P.E.; Draper, B.L.; Flores, R.S.

    1998-02-01

    Challenges related to radiation hardening CMOS technologies with shallow-trench isolation are explored. Results show that trench hardening can be more difficult than simply replacing the trench isolation oxide with a hardened field oxide

  18. Older Workers and Federal Work Programs: The Korean Senior Employment Program (KSEP).

    Science.gov (United States)

    Choi, Eunhee

    2016-01-01

    Federal older worker programs are attracting attention due to the growing number of older workers across the world. They are uniquely situated to provide out-of-market work opportunities to older job seekers, who often find their age a barrier to securing desirable jobs. In 2004, the Korean government established its own program, the Korean Senior Employment Program (KSEP); however, literature for international readers on this innovative program is lacking. Thus, this article aims to provide an in-depth description of KSEP and a brief comparison between the Senior Community Service Employment Program in the U.S. and KSEP. The unique characteristics of KSEP include having the dual program foci on supplemental income and social participation; expanding work opportunities in the private sector beyond community-based jobs; accepting participants who are financially disadvantaged as well as those with a high desire for social participation regardless of their income; and broadening work opportunities for those with professional skills beyond repetitive, simple, and temporary jobs. This article may offer helpful insights to older worker advocates from various countries in creating or modifying their programs.

  19. Electron beam hardened paint binder

    International Nuclear Information System (INIS)

    Johnson, O.B.; Labana, S.S.

    1976-01-01

    The invention concerns a paint binder hardened by the effect of electron beams (0.1-100 Mrad/sec). It consists of a dispersion of (A) an ethylenic unsaturated material in (B) at least one vinyl monomer. The component (A) in a reaction product of degraded rubber particles (0.1-4 μm) and an ethylenic unsaturated component with a reactive epoxy, hydroxy or carboxy group which is bonded to the rubber particles by ester or urethane compounds. The rubber particles possess a nucleus and a cross-linked elastomeric acryl polymer, an outer shell with reactive groups and an intermediate layer formed by the monomers of the nucleus and the shell. The manner of production is described in great detail and supplemented by 157 examples. The coatings are suitable to coat articles which will be subject to deformation. (UWI) [de

  20. Radiation hardening of smart electronics

    International Nuclear Information System (INIS)

    Mayo, C.W.; Cain, V.R.; Marks, K.A.; Millward, D.G.

    1991-02-01

    Microprocessor based ''smart'' pressure, level, and flow transmitters were tested to determine the radiation hardness of this class of electronic instrumentation for use in reactor building applications. Commercial grade Complementary Metal Oxide Semiconductor (CMOS) integrated circuits used in these transmitters were found to fail at total gamma dose levels between 2500 and 10,000 rad. This results in an unacceptably short lifetime in many reactor building radiation environments. Radiation hardened integrated circuits can, in general, provide satisfactory service life for normal reactor operations when not restricted to the extremely low power budget imposed by standard 4--20 mA two-wire instrument loops. The design of these circuits will require attention to vendor radiation hardness specifications, dose rates, process control with respect to radiation hardness factors, and non-volatile programmable memory technology. 3 refs., 2 figs

  1. Design Features of Hardening Turners with Outstripping Plastic Deformation

    Directory of Open Access Journals (Sweden)

    V. M. Yaroslavtsev

    2014-01-01

    Full Text Available An efficiency of the cutting method with outstripping plastic deformation (OPD in lathe works is defined in many respects by design features of the add-on devices for mechanical hardening of a cut-off layer material in the course of cutting. Applied on lathes, deforming OPD devices can have differing dimensions, placement on the lathe, drive type (manual, electric, hydraulic, pneumatic, pneumohydraulic, electromagnetic, and autonomy degree towards the metalcutting equipment and industrial equipment.At the same time there are a number of inherent design features of work-hardening devices the modernized lathes with OPD use for machining. Now the OPD standard devices implement two principle construction options: loading device is placed on the machine or on the OPD slide support separate of the tool, or it is structurally aligned with the cutting tool. In the latter case the OPD device for turning is called a tool mandrel, which is mounted in a tool post of the machine or, at large dimensions, such a mandrel is mounted on the machine instead of the tool mandrel.When designing the OPD devices, is important to take into consideration production requirements and recommendations for the technological equipment, developed in the course of creation, working off and introduction of such installations for mechanical hardening of material. In compliance with it, OPD devices, their placement on the machine, and working displacements shouldn't limit technological capabilities of the applied metal-cutting equipment. OPD stresses have to be smoothly regulated, with maximum loads being limited to admissible values for the machine model to be modernized. It is necessary to ensure synchronized longitudinal and cross displacements of the cutting tool and OPD hardener with respect to the axis of billet rotation to enable regulation and readjustment of the hardener and tool placement. It ought to foresee the increased mobile components rigidity and manufacturing

  2. A radiation-hardened SOI-based FPGA

    International Nuclear Information System (INIS)

    Han Xiaowei; Wu Lihua; Zhao Yan; Li Yan; Zhang Qianli; Chen Liang; Zhang Guoquan; Li Jianzhong; Yang Bo; Gao Jiantou; Wang Jian; Li Ming; Liu Guizhai; Zhang Feng; Guo Xufeng; Chen, Stanley L.; Liu Zhongli; Yu Fang; Zhao Kai

    2011-01-01

    A radiation-hardened SRAM-based field programmable gate array VS1000 is designed and fabricated with a 0.5 μm partial-depletion silicon-on-insulator logic process at the CETC 58th Institute. The new logic cell (LC), with a multi-mode based on 3-input look-up-table (LUT), increases logic density about 12% compared to a traditional 4-input LUT The logic block (LB), consisting of 2 LCs, can be used in two functional modes: LUT mode and distributed read access memory mode. The hierarchical routing channel block and switch block can significantly improve the flexibility and routability of the routing resource. The VS1000 uses a CQFP208 package and contains 392 reconfigurable LCs, 112 reconfigurable user I/Os and IEEE 1149.1 compatible with boundary-scan logic for testing and programming. The function test results indicate that the hardware and software cooperate successfully and the VS1000 works correctly. Moreover, the radiation test results indicate that the VS1000 chip has total dose tolerance of 100 krad(Si), a dose rate survivability of 1.5 x 10 11 rad(Si)/s and a neutron fluence immunity of 1 x 10 14 n/cm 2 . (semiconductor integrated circuits)

  3. Strain hardening behavior and microstructural evolution during plastic deformation of dual phase, non-grain oriented electrical and AISI 304 steels

    Energy Technology Data Exchange (ETDEWEB)

    Soares, Guilherme Corrêa; Gonzalez, Berenice Mendonça; Arruda Santos, Leandro de, E-mail: leandro.arruda@demet.ufmg.br

    2017-01-27

    Strain hardening behavior and microstructural evolution of non-grain oriented electrical, dual phase, and AISI 304 steels, subjected to uniaxial tensile tests, were investigated in this study. Tensile tests were performed at room temperature and the strain hardening behavior of the steels was characterized by three different parameters: modified Crussard–Jaoul stages, strain hardening rate and instantaneous strain hardening exponent. Optical microscopic analysis, X-ray diffraction measurements, phase quantification by Rietveld refinement and hardness tests were also carried out in order to correlate the microstructural and mechanical responses to plastic deformation. Distinct strain hardening stages were observed in the steels in terms of the instantaneous strain hardening exponent and the strain hardening rate. The dual phase and non-grain oriented steels exhibited a two-stage strain hardening behavior while the AISI 304 steel displayed multiple stages, resulting in a more complex strain hardening behavior. The dual phase steels showed a high work hardening capacity in stage 1, which was gradually reduced in stage 2. On the other hand, the AISI 304 steel showed high strain hardening capacity, which continued to increase up to the tensile strength. This is a consequence of its additional strain hardening mechanism, based on a strain-induced martensitic transformation, as shown by the X-ray diffraction and optical microscopic analyses.

  4. Implementation of the Danish return-to-work program

    DEFF Research Database (Denmark)

    Aust, Birgit; D. Nielsen, Maj Britt; Grundtvig, Gry

    2015-01-01

    OBJECTIVES: The aim of this study was to evaluate the implementation of the Danish national return-to-work (RTW) program in 21 Danish municipalities. METHODS: We conducted a structured process evaluation on (i) reach and recruitment, (ii) fidelity, (iii) dose-delivered, (iv) dose-received, and (v...... (defined as implementation consistent with the principles of the interdisciplinary RTW process). Five municipalities had high and eight had low fidelity scores. Similar large differences were found with regard to dose-delivered, particularly in the quality of cooperation with beneficiaries, employers...

  5. Some aspects of plasticity in hardened face-centred cubic metals

    International Nuclear Information System (INIS)

    Jackson, P.J.; Nathanson, P.D.K.

    1978-01-01

    The plasticity of crystals of f.c.c. metals hardened by solute atoms, neutron irradiation, quenching and by dislocation distributions not characteristic of the active mode of testing is reviewed, with emphasis being placed on the simiularity of slip after various hardening treatments. Normal work hardening is not treated. The reasons for this exclusion are discussed. It is concluded that correlated slip is a normal aspect of deformation, and that diffuse uncorrelated slip occurs only when secondary dislocation multiplication is promoted, e.g. by obstacles introduced by prior slip, or by the presence of hard impenetrable obstacles of another material or phase [af

  6. Orowan strengthening and forest hardening superposition examined by dislocation dynamics simulations

    International Nuclear Information System (INIS)

    Queyreau, Sylvain; Monnet, Ghiath; Devincre, Benoit

    2010-01-01

    Rule of mixtures are an essential feature of the modeling of plastic deformation in complex materials in which more than one strain-hardening mechanism is involved. In this work, use is made of dislocation dynamics simulations to characterize the individual and the superposed contributions of two major mechanisms of crystal plasticity, i.e. Orowan strengthening and forest hardening. Based on a formal description of each hardening mechanism, evidence is presented to show that a quadratic rule of mixtures has the ability to predict quantitatively the flow stress of complex materials such as reactor pressure vessel steel.

  7. Account of low temperature hardening in calculation of permissible stresses

    International Nuclear Information System (INIS)

    Novikov, N.V.; Ul'yanenko, A.P.; Gorodyskij, N.I.

    1980-01-01

    Suggested is a calculation scheme of permissible stresses with the account of temperature hardening for steels and alloys, the dependences of strength, plasticity and rupture work of which on cooling temperature do not have threshold changes in a wide range of low temperatures (from 300 to 4.2 K). Application of the suggested scheme is considered on the example of 12Kh18N10T austenitic chromium-nickel steel

  8. Description of hardening curves of fcc single- and polycrystals

    International Nuclear Information System (INIS)

    Mecking, H.

    1975-01-01

    Stress-strain curves are analyzed over their entire strain region and over a wide range of temperatures to arrive at a general analytic description of work-hardening curves. The data were obtained with fcc single and polycrystals, but there is experimental and theoretical evidence that the principles of the analysis are also applicable for other crystal structures and even for more complex technical materials. 9 figs, 1 table, 46 refs

  9. Laser Surface Hardening of Groove Edges

    Science.gov (United States)

    Hussain, A.; Hamdani, A. H.; Akhter, R.; Aslam, M.

    2013-06-01

    Surface hardening of groove-edges made of 3Cr13 Stainless Steel has been carried out using 500 W CO2 laser with a rectangular beam of 2.5×3 mm2. The processing speed was varied from 150-500 mm/min. It was seen that the hardened depth increases with increase in laser interaction time. A maximum hardened depth of around 1mm was achieved. The microhardness of the transformed zone was 2.5 times the hardness of base metal. The XRD's and microstructural analysis were also reported.

  10. Beyond Work-Family Programs: Confronting and Resolving the Underlying Causes of Work-Personal Life Conflict.

    Science.gov (United States)

    Kofodimos, Joan R.

    Work-Family Programs (WFPs) are among the most popular and publicized workplace innovations of the 1990s. These programs are intended to alleviate employees' work-personal conflicts by addressing issues such as child care assistance, parental leave, elder care, flexible working arrangements, wellness and fitness, and stress management. The problem…

  11. A short executive function training program improves preschoolers’ working memory

    Directory of Open Access Journals (Sweden)

    Emma eBlakey

    2015-11-01

    Full Text Available Cognitive training has been shown to improve executive functions in middle childhood and adulthood. However, fewer studies have targeted the preschool years – a time when executive functions undergo rapid development. The present study tested the effects of a short four session executive function training program in 54 four-year-olds. The training group significantly improved their working memory from pre-training relative to an active control group. Notably, this effect extended to a task sharing few surface features with the trained tasks, and continued to be apparent three months later. In addition, the benefits of training extended to a measure of mathematical reasoning three months later, indicating that training executive functions during the preschool years has the potential to convey benefits that are both long-lasting and wide-ranging.

  12. Different Techniques For Producing Precision Holes (>20 mm) In Hardened Steel—Comparative Results

    Science.gov (United States)

    Coelho, R. T.; Tanikawa, S. T.

    2009-11-01

    High speed machining (HSM), or high performance machining, has been one of the most recent technological advances. When applied to milling operations, using adequate machines, CAM programs and tooling, it allows cutting hardened steels, which was not feasible just a couple of years ago. The use of very stiff and precision machines has created the possibilities of machining holes in hardened steels, such as AISI H13 with 48-50 HRC, using helical interpolations, for example. Such process is particularly useful for holes with diameter bigger than normal solid carbide drills commercially available, around 20 mm, or higher. Such holes may need narrow tolerances, fine surface finishing, which can be obtained just by end milling operations. The present work compares some of the strategies used to obtain such holes by end milling, and also some techniques employed to finish them, by milling, boring and also by fine grinding at the same machine. Results indicate that it is possible to obtain holes with less than 0.36 m in circularity, 7.41 m in cylindricity and 0.12 m in surface roughness Ra. Additionally, there is less possibilities of obtaining heat affected layers when using such technique.

  13. Estimation of radiation hardening in ferritic steels using the cluster dynamics models

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Jun Hyun; Kim, Whung Whoe; Hong, Jun Hwa [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    2005-07-01

    Evolution of microstructure under irradiation brings about the mechanical property changes of materials, of which the major concern is radiation hardening in this work. Radiation hardening is generally expressed in terms of an increase in yield strength as a function of radiation dose and temperature. Cluster dynamics model for radiation hardening has been developed to describe the evolution of point defects clusters (PDCs) and copperrich precipitates (CRPs). While the mathematical models developed by Stoller focus on the evolution of PDCs in ferritic steels under neutron irradiation, we slightly modify the model by including the CRP growth and estimate the magnitude of hardening induced by PDC and CRP. The model is then used to calculate the changes in yield strength of RPV steels. The calculation results are compared to measured yield strength values, obtained from surveillance testing of PWR vessel steels in France.

  14. Simulating the influence of scatter and beam hardening in dimensional computed tomography

    Science.gov (United States)

    Lifton, J. J.; Carmignato, S.

    2017-10-01

    Cone-beam x-ray computed tomography (XCT) is a radiographic scanning technique that allows the non-destructive dimensional measurement of an object’s internal and external features. XCT measurements are influenced by a number of different factors that are poorly understood. This work investigates how non-linear x-ray attenuation caused by beam hardening and scatter influences XCT-based dimensional measurements through the use of simulated data. For the measurement task considered, both scatter and beam hardening are found to influence dimensional measurements when evaluated using the ISO50 surface determination method. On the other hand, only beam hardening is found to influence dimensional measurements when evaluated using an advanced surface determination method. Based on the results presented, recommendations on the use of beam hardening and scatter correction for dimensional XCT are given.

  15. Plastic limit analysis with non linear kinematic strain hardening for metalworking processes applications

    International Nuclear Information System (INIS)

    Chaaba, Ali; Aboussaleh, Mohamed; Bousshine, Lahbib; Boudaia, El Hassan

    2011-01-01

    Limit analysis approaches are widely used to deal with metalworking processes analysis; however, they are applied only for perfectly plastic materials and recently for isotropic hardening ones excluding any kind of kinematic hardening. In the present work, using Implicit Standard Materials concept, sequential limit analysis approach and the finite element method, our objective consists in extending the limit analysis application for including linear and non linear kinematic strain hardenings. Because this plastic flow rule is non associative, the Implicit Standard Materials concept is adopted as a framework of non standard plasticity modeling. The sequential limit analysis procedure which considers the plastic behavior with non linear kinematic strain hardening as a succession of perfectly plastic behavior with yielding surfaces updated after each sequence of limit analysis and geometry updating is applied. Standard kinematic finite element method together with a regularization approach is used for performing two large compression cases (cold forging) in plane strain and axisymmetric conditions

  16. Influences of Steelmaking Slags on Hydration and Hardening of Concretes

    Science.gov (United States)

    Kirsanova, A. A.; Dildin, A. N.; Maksimov, S. P.

    2017-11-01

    It is shown that the slag of metallurgical production can be used in the construction industry as an active mineral additive for concrete. This approach allows us to solve environmental problems and reduce costs for the production of binder and concrete simultaneously. Most often slag is used in the form of a filler, an active mineral additive or as a part of a binder for artificial conglomerates. The introduction of slag allows one to notice a part of the cement, to obtain concretes that are more resistant to the impact of aggressive sulfate media. The paper shows the possibility of using recycled steel-smelting slags in the construction industry for the production of cement. An assessment was made of their effect on the hydration of the cement stone and hardening of the concrete together with the plasticizer under normal conditions. In the process of work, we used the slag of the Zlatoust Electrometallurgical Factory. Possible limitations of the content of steel-slag slag in concrete because of the possible presence of harmful impurities are shown. It is necessary to enter slag in conjunction with superplasticizers to reduce the flow of water mixing. Slags can be used as a hardening accelerator for cement concrete as they allow one to increase the degree of cement hydration and concrete strength. It is shown that slags can be used to produce fast-hardening concretes and their comparative characteristics with other active mineral additives are given.

  17. Plasma nitriding - an eco friendly surface hardening process

    International Nuclear Information System (INIS)

    Mukherjee, S.

    2015-01-01

    Surface hardening is a process of heating the metal such that the surface gets only hardened. This process is adopted for many components like gears, cams, and crankshafts, which desire high hardness on the outer surface with a softer core to withstand the shocks. So, to attain such properties processes like carburising, nitriding, flame hardening and induction hardening are employed. Amongst these processes nitriding is the most commonly used process by many industries. In nitriding process the steel material is heated to a temperature of around 550 C and then exposed to atomic nitrogen. This atomic nitrogen reacts with iron and other alloying elements and forms nitrides, which are very hard in nature. By this process both wear resistance and hardness of the product can be increased. The atomic nitrogen required for this process can be obtained using ammonia gas (gas nitriding), cyanide based salt bath (liquid nitriding) and plasma medium (plasma nitriding). However, plasma nitriding has recently received considerable industrial interest owing to its characteristic of faster nitrogen penetration, short treatment time, low process temperature, minimal distortion, low energy use and easier control of layer formation compared with conventional techniques such as gas and liquid nitriding. This process can be used for all ferrous materials including stainless steels. Plasma nitriding is carried out using a gas mixture of nitrogen and hydrogen gas at sub atmospheric pressures hence, making it eco-friendly in nature. Plasma nitriding allows modification of the surface layers and hardness profiles by changing the gas mixture and temperature. The wide applicable temperature range enables a multitude of applications, beyond the possibilities of gas or salt bath processes. This has led to numerous applications of this process in industries such as the manufacture of machine parts for plastics and food processing, packaging and tooling as well as pumps and hydraulic, machine

  18. Reduction of metal artifacts: beam hardening and photon starvation effects

    Science.gov (United States)

    Yadava, Girijesh K.; Pal, Debashish; Hsieh, Jiang

    2014-03-01

    The presence of metal-artifacts in CT imaging can obscure relevant anatomy and interfere with disease diagnosis. The cause and occurrence of metal-artifacts are primarily due to beam hardening, scatter, partial volume and photon starvation; however, the contribution to the artifacts from each of them depends on the type of hardware. A comparison of CT images obtained with different metallic hardware in various applications, along with acquisition and reconstruction parameters, helps understand methods for reducing or overcoming such artifacts. In this work, a metal beam hardening correction (BHC) and a projection-completion based metal artifact reduction (MAR) algorithms were developed, and applied on phantom and clinical CT scans with various metallic implants. Stainless-steel and Titanium were used to model and correct for metal beam hardening effect. In the MAR algorithm, the corrupted projection samples are replaced by the combination of original projections and in-painted data obtained by forward projecting a prior image. The data included spine fixation screws, hip-implants, dental-filling, and body extremity fixations, covering range of clinically used metal implants. Comparison of BHC and MAR on different metallic implants was used to characterize dominant source of the artifacts, and conceivable methods to overcome those. Results of the study indicate that beam hardening could be a dominant source of artifact in many spine and extremity fixations, whereas dental and hip implants could be dominant source of photon starvation. The BHC algorithm could significantly improve image quality in CT scans with metallic screws, whereas MAR algorithm could alleviate artifacts in hip-implants and dentalfillings.

  19. Effects of residual stress on irradiation hardening in stainless steels

    Energy Technology Data Exchange (ETDEWEB)

    Okubo, N.; Kondo, K.; Kaji, Y. [Japan Atomic Energy Agency, Tokai-mura, Naga-gun, Ibaraki-ken (Japan); Miwa, Y. [Nuclear Energy and Science Directorate, Japan Atomic Energy Agency, Tokai-mura, Ibaraki-ken (Japan)

    2007-07-01

    Full text of publication follows: Structural materials in fusion reactor with water cooling system will undergo corrosion in aqueous environment and heavier irradiation than that in LWR. Irradiation assisted stress corrosion (IASCC) may be induced in stainless steels exposed in these environment for a long term of reactor operation. The IASCC is considered to be caused in a welding zone. It is difficult to predict and estimate the IASCC, because several irradiation effects (irradiation hardening, swelling, irradiation induced stress relaxation, etc) work intricately. Firstly, effects of residual stress on irradiation hardening were investigated in stainless steels. Specimens used in this study were SUS316 and SUS316L. By bending deformation, the specimens with several % plastic strain, which corresponds to weld residual stress, were prepared. Ion irradiations of 12 MeV Ni{sup 3+} were performed at 330, 400 and 550 deg. C to 45 dpa in TIARA facility at JAEA. No bent specimen was simultaneously irradiated with the bent specimen. The residual stress was estimated by X-ray residual stress measurements before and after the irradiation. The micro-hardness was measured by using nano-indenter. The irradiation hardening and the stress relaxation were changed by irradiation under bending deformation. The residual stress did not relax even for the case of the higher temperature aging at 500 deg. C for the same time of irradiation. The residual stress after ion irradiation, however, relaxed at these experimental temperatures in SUS316L. The hardness was obviously suppressed in bent SUS316L irradiated at 300 deg. C to 6 or 12 dpa. It was evident that irradiation induced stress relaxation occasionally suppressed the irradiation hardening in SUS316L. (authors)

  20. Effective Ways to Realize the Character Education Value of Work-study Program

    Directory of Open Access Journals (Sweden)

    Lv Xuemei PhD Student

    2013-07-01

    Full Text Available This paper indicates work-study program can foster the character development of college students as an important content of social practice activities in university. It suggests strategies for realizing the character education value of work-study program. First, establish a specific character education object for every work-study program. Second, use the controllability of the classroom to make up the uncontrollability of work-study program. Third, set up an effective supervision and evaluation mechanism.

  1. Simultaneous surface engineering and bulk hardening of precipitation hardening stainless steel

    DEFF Research Database (Denmark)

    Frandsen, Rasmus Berg; Christiansen, Thomas; Somers, Marcel A. J.

    2006-01-01

    This article addresses simultaneous bulk precipitation hardening and low temperature surface engineering of two commercial precipitation hardening stainless steels: Sandvik Nanoflex® and Uddeholm Corrax®. Surface engineering comprised gaseous nitriding or gaseous carburising. Microstructural....... The duration and temperature of the nitriding/carburising surface hardening treatment can be chosen in agreement with the thermal treatment for obtaining optimal bulk hardness in the precipitation hardening stainless steel....... characterisation of the cases developed included X-ray diffraction analysis, reflected light microscopy and micro-hardness testing. It was found that the incorporation of nitrogen or carbon resulted in a hardened case consisting of a combination of (tetragonal) martensite and expanded (cubic) austenite...

  2. Precipitation and Hardening in Magnesium Alloys

    Science.gov (United States)

    Nie, Jian-Feng

    2012-11-01

    Magnesium alloys have received an increasing interest in the past 12 years for potential applications in the automotive, aircraft, aerospace, and electronic industries. Many of these alloys are strong because of solid-state precipitates that are produced by an age-hardening process. Although some strength improvements of existing magnesium alloys have been made and some novel alloys with improved strength have been developed, the strength level that has been achieved so far is still substantially lower than that obtained in counterpart aluminum alloys. Further improvements in the alloy strength require a better understanding of the structure, morphology, orientation of precipitates, effects of precipitate morphology, and orientation on the strengthening and microstructural factors that are important in controlling the nucleation and growth of these precipitates. In this review, precipitation in most precipitation-hardenable magnesium alloys is reviewed, and its relationship with strengthening is examined. It is demonstrated that the precipitation phenomena in these alloys, especially in the very early stage of the precipitation process, are still far from being well understood, and many fundamental issues remain unsolved even after some extensive and concerted efforts made in the past 12 years. The challenges associated with precipitation hardening and age hardening are identified and discussed, and guidelines are outlined for the rational design and development of higher strength, and ultimately ultrahigh strength, magnesium alloys via precipitation hardening.

  3. Segmentation-free empirical beam hardening correction for CT

    Energy Technology Data Exchange (ETDEWEB)

    Schüller, Sören; Sawall, Stefan [German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120 (Germany); Stannigel, Kai; Hülsbusch, Markus; Ulrici, Johannes; Hell, Erich [Sirona Dental Systems GmbH, Fabrikstraße 31, 64625 Bensheim (Germany); Kachelrieß, Marc, E-mail: marc.kachelriess@dkfz.de [German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany)

    2015-02-15

    Purpose: The polychromatic nature of the x-ray beams and their effects on the reconstructed image are often disregarded during standard image reconstruction. This leads to cupping and beam hardening artifacts inside the reconstructed volume. To correct for a general cupping, methods like water precorrection exist. They correct the hardening of the spectrum during the penetration of the measured object only for the major tissue class. In contrast, more complex artifacts like streaks between dense objects need other techniques of correction. If using only the information of one single energy scan, there are two types of corrections. The first one is a physical approach. Thereby, artifacts can be reproduced and corrected within the original reconstruction by using assumptions in a polychromatic forward projector. These assumptions could be the used spectrum, the detector response, the physical attenuation and scatter properties of the intersected materials. A second method is an empirical approach, which does not rely on much prior knowledge. This so-called empirical beam hardening correction (EBHC) and the previously mentioned physical-based technique are both relying on a segmentation of the present tissues inside the patient. The difficulty thereby is that beam hardening by itself, scatter, and other effects, which diminish the image quality also disturb the correct tissue classification and thereby reduce the accuracy of the two known classes of correction techniques. The herein proposed method works similar to the empirical beam hardening correction but does not require a tissue segmentation and therefore shows improvements on image data, which are highly degraded by noise and artifacts. Furthermore, the new algorithm is designed in a way that no additional calibration or parameter fitting is needed. Methods: To overcome the segmentation of tissues, the authors propose a histogram deformation of their primary reconstructed CT image. This step is essential for the

  4. Segmentation-free empirical beam hardening correction for CT.

    Science.gov (United States)

    Schüller, Sören; Sawall, Stefan; Stannigel, Kai; Hülsbusch, Markus; Ulrici, Johannes; Hell, Erich; Kachelrieß, Marc

    2015-02-01

    The polychromatic nature of the x-ray beams and their effects on the reconstructed image are often disregarded during standard image reconstruction. This leads to cupping and beam hardening artifacts inside the reconstructed volume. To correct for a general cupping, methods like water precorrection exist. They correct the hardening of the spectrum during the penetration of the measured object only for the major tissue class. In contrast, more complex artifacts like streaks between dense objects need other techniques of correction. If using only the information of one single energy scan, there are two types of corrections. The first one is a physical approach. Thereby, artifacts can be reproduced and corrected within the original reconstruction by using assumptions in a polychromatic forward projector. These assumptions could be the used spectrum, the detector response, the physical attenuation and scatter properties of the intersected materials. A second method is an empirical approach, which does not rely on much prior knowledge. This so-called empirical beam hardening correction (EBHC) and the previously mentioned physical-based technique are both relying on a segmentation of the present tissues inside the patient. The difficulty thereby is that beam hardening by itself, scatter, and other effects, which diminish the image quality also disturb the correct tissue classification and thereby reduce the accuracy of the two known classes of correction techniques. The herein proposed method works similar to the empirical beam hardening correction but does not require a tissue segmentation and therefore shows improvements on image data, which are highly degraded by noise and artifacts. Furthermore, the new algorithm is designed in a way that no additional calibration or parameter fitting is needed. To overcome the segmentation of tissues, the authors propose a histogram deformation of their primary reconstructed CT image. This step is essential for the proposed

  5. Dyslexia Training Program. What Works Clearinghouse Intervention Report

    Science.gov (United States)

    What Works Clearinghouse, 2010

    2010-01-01

    The "Dyslexia Training Program," developed at the Texas Scottish Rite Hospital for Children, is a Tier III reading intervention program that provides intensive phonics instruction to children with dyslexia, primarily in grades two through five. It is a comprehensive two-year program that bridges the gap for school districts in which a…

  6. A procedure for the hardening of materials

    International Nuclear Information System (INIS)

    Dearnaley, G.

    1984-01-01

    A method of hardening metals or ceramics which have fcc, bcc or hcp structures in which two species of differing atomic radii are introduced into the material to be hardened. One species is of a size such that it can diffuse through the lattice normally. The other is of a size such that it can diffuse readily only along dislocations. Ion bombardment is the preferred method of introducing the species with different atomic radii. The material to be hardened is subjected to heat and plastic deformation so as to cause a large number of dislocations with jogs. The species meet at the jogs where they interact and are trapped and set up strain fields which prevent further deformation of the material. (author)

  7. An Anisotropic Hardening Model for Springback Prediction

    Science.gov (United States)

    Zeng, Danielle; Xia, Z. Cedric

    2005-08-01

    As more Advanced High-Strength Steels (AHSS) are heavily used for automotive body structures and closures panels, accurate springback prediction for these components becomes more challenging because of their rapid hardening characteristics and ability to sustain even higher stresses. In this paper, a modified Mroz hardening model is proposed to capture realistic Bauschinger effect at reverse loading, such as when material passes through die radii or drawbead during sheet metal forming process. This model accounts for material anisotropic yield surface and nonlinear isotropic/kinematic hardening behavior. Material tension/compression test data are used to accurately represent Bauschinger effect. The effectiveness of the model is demonstrated by comparison of numerical and experimental springback results for a DP600 straight U-channel test.

  8. An Anisotropic Hardening Model for Springback Prediction

    International Nuclear Information System (INIS)

    Zeng, Danielle; Xia, Z. Cedric

    2005-01-01

    As more Advanced High-Strength Steels (AHSS) are heavily used for automotive body structures and closures panels, accurate springback prediction for these components becomes more challenging because of their rapid hardening characteristics and ability to sustain even higher stresses. In this paper, a modified Mroz hardening model is proposed to capture realistic Bauschinger effect at reverse loading, such as when material passes through die radii or drawbead during sheet metal forming process. This model accounts for material anisotropic yield surface and nonlinear isotropic/kinematic hardening behavior. Material tension/compression test data are used to accurately represent Bauschinger effect. The effectiveness of the model is demonstrated by comparison of numerical and experimental springback results for a DP600 straight U-channel test

  9. 13 CFR 120.340 - What is the Export Working Capital Program?

    Science.gov (United States)

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false What is the Export Working Capital... LOANS Special Purpose Loans Export Working Capital Program (ewcp) § 120.340 What is the Export Working Capital Program? Under the EWCP, SBA guarantees short-term working capital loans made by participating...

  10. Technology of hardening fills for mined spaces

    International Nuclear Information System (INIS)

    Simek, P.; Holas, M.; Chyla, A.; Pech, P.

    1985-01-01

    The technology is described of hardening fills for mined spaces of uranium deposits in North Bohemian chalk. A special equipment was developed for the controlled preparation of a hardening mixture. The composition of the fill is determined by the strength of the filled rock, expecially by the standard strength, i.e., the minimal strength of the filling under uniaxial pressure. The said parameter determines the consumption of binding materials and thereby the total costs of the filling. A description is presented of the filling technology, including rabbit tube transport of the mixture and quality control. (Pu)

  11. Radiation hardening revisited: Role of intracascade clustering

    DEFF Research Database (Denmark)

    Singh, B.N.; Foreman, A.J.E.; Trinkaus, H.

    1997-01-01

    be explained in terms of conventional dispersed-barrier hardening because (a) the grown-in dislocations are not free, and (b) irradiation-induced defect clusters are not rigid indestructible Orowan obstacles. A new model called 'cascade-induced source hardening' is presented where glissile loops produced...... directly in cascades are envisaged to decorate the grown-in dislocations so that they cannot act as dislocation sources. The upper yield stress is related to the breakaway stress which is necessary to pull the dislocation away from the clusters/loops decorating it. The magnitude of the breakaway stress has...

  12. Behavior of surface residual stress in explosion hardened high manganese austenitic cast steel due to repeated impact loads

    International Nuclear Information System (INIS)

    Oda, Akira; Miyagawa, Hideaki

    1985-01-01

    Explosion hardened high manganese austenitic cast steel is being tried for rail crossing recently. From the previous studies, it became clear that high tensile residual stress was generated in the hardened surface layer by explosion and microcracks were observed. In this study, therefore, the behavior of surface residual stress in explosion hardened steel due to repeated impact loads was examined and compared with those of the original and shot peened steels. The results obtained are summarized as follows: (1) In the initial stage of the repetition of impact, high tensile surface residual stress in explosion hardened steel decreased rapidly with the repetition of impact, while those of the original and shot peened steels increased rapidly. This difference was attributed to the difference in depth of the work hardened layer in three testing materials. (2) Beyond 20 impacts the residual stress of three test specimens decreased gradually, and at more than 2000 impacts the compressive stress of about 500 MPa was produced regardless of the histories of working of testing materials. (3) The linear law in the second stage of residual stress fading was applicable to this case, and the range of the linear relationship was related to the depth of the work hardened layer of testing material. (4) From the changes in half-value breadth and peak intensity of diffraction X-ray, it was supposed that a peculiar microscopic strain exists in explosion hardened steel. (author)

  13. Why and How Schools Make Nutrition Education Programs "Work"

    Science.gov (United States)

    Porter, Kathleen J.; Koch, Pamela A.; Contento, Isobel R.

    2018-01-01

    Background: There are many potential health benefits to having nutrition education programs offered by expert outside sources in schools. However, little is known about why and how schools initiate, implement, and institutionalize them. Gaining this understanding may allow the impact and reach of nutrition and other health education programs in…

  14. State Energy Program Results: More Projects That Work

    Energy Technology Data Exchange (ETDEWEB)

    1998-12-01

    A Summary of Success stories of the State Energy Programs. The goal of the State Energy Program is to strengthen the capabilities of States to promote energy efficiency and to adopt renewable energy technologies, thereby helping the nation save energy and realize a stronger economy, cleaner environment, and a more secure future.

  15. Summer Bridge Programs. What Works Clearinghouse Intervention Report

    Science.gov (United States)

    What Works Clearinghouse, 2016

    2016-01-01

    "Summer bridge programs" are designed to ease the transition to college and support postsecondary success by providing students with the academic skills and social resources needed to succeed in a college environment. These programs occur in the summer "bridge" period between high school and college. Although the content of…

  16. Credit Recovery Programs. What Works Clearinghouse Intervention Report

    Science.gov (United States)

    What Works Clearinghouse, 2015

    2015-01-01

    "Credit recovery programs" allow high school students to recover course credit, through in-school, online, or mixed modes, for classes they previously failed. The WWC reviewed the research on these programs and their impacts on middle school, junior high school, or high school students at risk of dropping out or who have already dropped…

  17. Working Together. Multi Purpose Programs for Troubled Youth.

    Science.gov (United States)

    Kuhn, Deborah; Pressman, Harvey

    This paper provides program planners with some innovative ideas that have been used in all phases of various multi-service programs for high-risk youth. Chapter 2 focuses on strategies for assessing participant needs. Diagnosis, learning disabilities and remediation, and staff training are discussed. Chapter 3 considers elimination of service gaps…

  18. 76 FR 23177 - Exchange Visitor Program-Summer Work Travel

    Science.gov (United States)

    2011-04-26

    ...--Summer Work Travel AGENCY: Department of State. ACTION: Interim final rule with request for comment... below, this rule modifies the Summer Work Travel regulations by establishing different employment..., the Department is establishing a new Summer Work Travel framework that recognizes potential underlying...

  19. General Friction Model Extended by the Effect of Strain Hardening

    DEFF Research Database (Denmark)

    Nielsen, Chris V.; Martins, Paulo A.F.; Bay, Niels

    2016-01-01

    An extension to the general friction model proposed by Wanheim and Bay [1] to include the effect of strain hardening is proposed. The friction model relates the friction stress to the fraction of real contact area by a friction factor under steady state sliding. The original model for the real...... contact area as function of the normalized contact pressure is based on slip-line analysis and hence on the assumption of rigid-ideally plastic material behavior. In the present work, a general finite element model is established to, firstly, reproduce the original model under the assumption of rigid...

  20. The development of radiation hardened robot for nuclear facility

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seung Ho; Jung, Seung Ho; Kim, Byung Soo and others

    2000-04-01

    The work conducted in this stage covers development of core technology of tele-robot system including monitoring technique in high-level radioactive area, tele-sensing technology and radiation-hardened technology for the non-destructive tele-inspection system which monitors the primary coolant system during the normal operations of PHWR(Pressurized Heavy Water Reactor) NPPs and measures the decrease of bending part of feeder pipe during overall. Based on the developed core technology, the monitoring mobile robot system of the primary coolant system and the feeder pipe inspecting robot system are developed.

  1. The development of radiation hardened robot for nuclear facility

    International Nuclear Information System (INIS)

    Kim, Seung Ho; Jung, Seung Ho; Kim, Byung Soo and others

    2000-04-01

    The work conducted in this stage covers development of core technology of tele-robot system including monitoring technique in high-level radioactive area, tele-sensing technology and radiation-hardened technology for the non-destructive tele-inspection system which monitors the primary coolant system during the normal operations of PHWR(Pressurized Heavy Water Reactor) NPPs and measures the decrease of bending part of feeder pipe during overall. Based on the developed core technology, the monitoring mobile robot system of the primary coolant system and the feeder pipe inspecting robot system are developed

  2. Career Advancement and Work Support Services on the Job: Implementing the Fort Worth Work Advancement and Support Center Program

    Science.gov (United States)

    Schultz, Caroline; Seith, David

    2011-01-01

    The Work Advancement and Support Center (WASC) program in Fort Worth was part of a demonstration that is testing innovative strategies to help increase the income of low-wage workers, who make up a large segment of the U.S. workforce. The program offered services to help workers stabilize their employment, improve their skills, and increase their…

  3. Social Work Programs' Use of the World Wide Web to Facilitate Field Instruction

    Directory of Open Access Journals (Sweden)

    Jerry Finn

    2001-05-01

    Full Text Available Employing a systems model, this study presents a content analysis of the Websites of social work academic programs in the United States. A sample of 292 academic programs was extracted from the Baccalaureate Programs' Directors' (BPD online directory of CSWE-accredited social work programs. Of these, 119 were MSW or MSW/BSW programs; the remaining 173 were BSW programs. Although many aspects of Website content were examined, field curriculum was the central focus of this study. The results demonstrate the wide variety of information included on the Websites. MSW and MSW/BSW program Websites offer more information than BSW programs. However, most programs are not making use of the Internet to obtain feedback, create interaction, or provide support. A variety of model Websites are offered to assist social work academic programs develop and maintain their own Websites.

  4. Weatherization Works: Weatherization Assistance Program Close-Up Fact Sheet

    International Nuclear Information System (INIS)

    2001-01-01

    The United States demonstrates its commitment to technology and efficiency through the Weatherization Program. Weatherization uses advanced technologies and techniques to reduce energy costs for low-income families by increasing the energy efficiency of their homes

  5. [Microstructural changes in hardened beans (Phaseolus vulgaris)].

    Science.gov (United States)

    Mujica, Maria Virginia; Granito, Marisela; Soto, Naudy

    2015-06-01

    (Phaseolus vulgaris). The hardening of Phaseolus vulgaris beans stored at high temperature and high relative humidity is one of the main constraints for consumption. The objective of this research was to evaluate by scanning electron microscopy, structural changes in cotyledons and testa of the hardened beans. The freshly harvested grains were stored for twelve months under two conditions: 5 ° C-34% RH and 37 ° C-75% RH, in order to promote hardening. The stored raw and cooked grains were lyophilized and fractured. The sections of testa and cotyledons were observed in an electron microscope JSM-6390. After twelve months, grains stored at 37 ° C-75% RH increased their hardness by 503%, whereas there were no significant changes in grains stored at 5 ° C-34% RH. At the microstructural level, the cotyledons of the raw grains show clear differences in appearance of the cell wall, into the intercellular space size and texture matrix protein. There were also differences in compaction of palisade and sub-epidermal layer in the testa of raw grains. After cooking, cotyledon cells of the soft grains were well separated while these ofhard grains were seldom separated. In conclusion, the found differences in hard and soft grains showed a significant participation of both structures, cotyledons and testa, in the grains hardening.

  6. Radiation dose effects, hardening of electronic components

    International Nuclear Information System (INIS)

    Dupont-Nivet, E.

    1991-01-01

    This course reviews the mechanism of interaction between ionizing radiation and a silicon oxide type dielectric, in particular the effect of electron-hole pairs creation in the material. Then effects of cumulated dose on electronic components and especially in MOS technology are examined. Finally methods hardening of these components are exposed. 93 refs

  7. CASE-HARDENING OF STAINLESS STEEL

    DEFF Research Database (Denmark)

    2004-01-01

    The invention relates to case-hardening of a stainless steel article by means of gas including carbon and/or nitrogen, whereby carbon and/or nitrogen atoms diffuse through the surface into the article. The method includes activating the surface of the article, applying a top layer on the activated...

  8. Thermomechanical properties of radiation hardened oligoesteracrylates

    International Nuclear Information System (INIS)

    Lomonosova, N.V.; Chikin, Yu.A.

    1984-01-01

    Thermomechanical properties of radiation hardened oligoesteracrylates are studied by the methods of isothermal heating and thermal mechanics. Films of dimethacrylate of ethylene glycol, triethylene glycol (TGM-3), tetraethylene glycol, tridecaethylene glycol and TGM-3 mixture with methyl methacrylate hardened by different doses (5-150 kGy) using Co 60 installation with a dose rate of 2x10 -3 kGy/s served as a subject of the research. During oligoesteracrylate hargening a space network is formed, chain sections between lattice points of which are in a stressed state. Maximum of deformation is observed at 210-220 deg C on thermomechanical curves of samples hardened by doses > 5 kGy, which form and intensity is dependent on an absorbed dose. Presence of a high-temperature maximum on diaqrams of isometric heating of spatially cross-linked oligoesteracrylates is discovered. High thermal stability of three-dimensional network of radiation hardened oligoesteracrylates provides satisfactory tensile properties (40% of initial strength) in sample testing an elevated temperatures (200-250 deg C)

  9. Observation of a New Mechanism Balancing Hardening and Softening in Metals

    DEFF Research Database (Denmark)

    Yu, Tianbo; Hansen, Niels; Huang, Xiaoxu

    2014-01-01

    Plastic deformation of metals refines the microstructure and increases the strength through work hardening, but this effect of deformation is counterbalanced by dynamic recovery. After large strain, the microstructure typically shows a lamellar morphology, with finely spaced lamellar boundaries...... connected by triple junctions. Here, we report that mechanically assisted triple junction motion is an important contributor to dynamic recovery, leading to an almost steady state. Triple junction motion replaces two boundaries by one, while maintaining the structural morphology. The observation...... rationalizes both a decreasing work hardening rate and the approach to a dynamic equilibrium of structural refinement at large strains....

  10. Transition Program: The Challenges Faced by Special Needs Students in Gaining Work Experience

    Science.gov (United States)

    Alias, Aliza

    2014-01-01

    Transition program for special needs students is known to open opportunities for students with learning disabilities to gain work experience in actual work environment. The program provides training activities and also an opportunity to go for internship to gain work experience. Therefore, this study is to identify the challenges faced by special…

  11. Statements of work handbook. [technical writing for NASA programs

    Science.gov (United States)

    1975-01-01

    Guidelines are presented for preparing statements of work (SOW) to assure a consistent approach throughout NASA. Statements of work for study and preliminary definition contracts, for definition and development of major systems, for support services, and for small research and development contracts are discussed.

  12. Modularity, Working Memory, and Second Language Acquisition: A Research Program

    Science.gov (United States)

    Truscott, John

    2017-01-01

    Considerable reason exists to view the mind, and language within it, as modular, and this view has an important place in research and theory in second language acquisition (SLA) and beyond. But it has had very little impact on the study of working memory and its role in SLA. This article considers the need for modular study of working memory,…

  13. A Working Ranch with an Effective Medusahead Management Program

    Science.gov (United States)

    Since 2005, rancher Ben McGough, owner of the Circle Bar Ranch in Mitchell, Oregon, has been working with USDA-ARS rangeland ecologist Roger Sheley to implement EBIPM on the ranch. More than 600 acres were infested with medusahead (Taeniatherum caput-medusae) when they began working together. We de...

  14. Multi-MGy Radiation Hardened Camera for Nuclear Facilities

    International Nuclear Information System (INIS)

    Girard, Sylvain; Boukenter, Aziz; Ouerdane, Youcef; Goiffon, Vincent; Corbiere, Franck; Rolando, Sebastien; Molina, Romain; Estribeau, Magali; Avon, Barbara; Magnan, Pierre; Paillet, Philippe; Duhamel, Olivier; Gaillardin, Marc; Raine, Melanie

    2015-01-01

    There is an increasing interest in developing cameras for surveillance systems to monitor nuclear facilities or nuclear waste storages. Particularly, for today's and the next generation of nuclear facilities increasing safety requirements consecutive to Fukushima Daiichi's disaster have to be considered. For some applications, radiation tolerance needs to overcome doses in the MGy(SiO 2 ) range whereas the most tolerant commercial or prototypes products based on solid state image sensors withstand doses up to few kGy. The objective of this work is to present the radiation hardening strategy developed by our research groups to enhance the tolerance to ionizing radiations of the various subparts of these imaging systems by working simultaneously at the component and system design levels. Developing radiation-hardened camera implies to combine several radiation-hardening strategies. In our case, we decided not to use the simplest one, the shielding approach. This approach is efficient but limits the camera miniaturization and is not compatible with its future integration in remote-handling or robotic systems. Then, the hardening-by-component strategy appears mandatory to avoid the failure of one of the camera subparts at doses lower than the MGy. Concerning the image sensor itself, the used technology is a CMOS Image Sensor (CIS) designed by ISAE team with custom pixel designs used to mitigate the total ionizing dose (TID) effects that occur well below the MGy range in classical image sensors (e.g. Charge Coupled Devices (CCD), Charge Injection Devices (CID) and classical Active Pixel Sensors (APS)), such as the complete loss of functionality, the dark current increase and the gain drop. We'll present at the conference a comparative study between these radiation-hardened pixel radiation responses with respect to conventional ones, demonstrating the efficiency of the choices made. The targeted strategy to develop the complete radiation hard camera

  15. Multi-MGy Radiation Hardened Camera for Nuclear Facilities

    Energy Technology Data Exchange (ETDEWEB)

    Girard, Sylvain; Boukenter, Aziz; Ouerdane, Youcef [Universite de Saint-Etienne, Lab. Hubert Curien, UMR-CNRS 5516, F-42000 Saint-Etienne (France); Goiffon, Vincent; Corbiere, Franck; Rolando, Sebastien; Molina, Romain; Estribeau, Magali; Avon, Barbara; Magnan, Pierre [ISAE, Universite de Toulouse, F-31055 Toulouse (France); Paillet, Philippe; Duhamel, Olivier; Gaillardin, Marc; Raine, Melanie [CEA, DAM, DIF, F-91297 Arpajon (France)

    2015-07-01

    There is an increasing interest in developing cameras for surveillance systems to monitor nuclear facilities or nuclear waste storages. Particularly, for today's and the next generation of nuclear facilities increasing safety requirements consecutive to Fukushima Daiichi's disaster have to be considered. For some applications, radiation tolerance needs to overcome doses in the MGy(SiO{sub 2}) range whereas the most tolerant commercial or prototypes products based on solid state image sensors withstand doses up to few kGy. The objective of this work is to present the radiation hardening strategy developed by our research groups to enhance the tolerance to ionizing radiations of the various subparts of these imaging systems by working simultaneously at the component and system design levels. Developing radiation-hardened camera implies to combine several radiation-hardening strategies. In our case, we decided not to use the simplest one, the shielding approach. This approach is efficient but limits the camera miniaturization and is not compatible with its future integration in remote-handling or robotic systems. Then, the hardening-by-component strategy appears mandatory to avoid the failure of one of the camera subparts at doses lower than the MGy. Concerning the image sensor itself, the used technology is a CMOS Image Sensor (CIS) designed by ISAE team with custom pixel designs used to mitigate the total ionizing dose (TID) effects that occur well below the MGy range in classical image sensors (e.g. Charge Coupled Devices (CCD), Charge Injection Devices (CID) and classical Active Pixel Sensors (APS)), such as the complete loss of functionality, the dark current increase and the gain drop. We'll present at the conference a comparative study between these radiation-hardened pixel radiation responses with respect to conventional ones, demonstrating the efficiency of the choices made. The targeted strategy to develop the complete radiation hard camera

  16. On the Spectral Hardening at gsim300 keV in Solar Flares

    Science.gov (United States)

    Li, G.; Kong, X.; Zank, G.; Chen, Y.

    2013-05-01

    It has long been noted that the spectra of observed continuum emissions in many solar flares are consistent with double power laws with a hardening at energies gsim300 keV. It is now widely believed that at least in electron-dominated events, the hardening in the photon spectrum reflects an intrinsic hardening in the source electron spectrum. In this paper, we point out that a power-law spectrum of electrons with a hardening at high energies can be explained by the diffusive shock acceleration of electrons at a termination shock with a finite width. Our suggestion is based on an early analytical work by Drury et al., where the steady-state transport equation at a shock with a tanh profile was solved for a p-independent diffusion coefficient. Numerical simulations with a p-dependent diffusion coefficient show hardenings in the accelerated electron spectrum that are comparable with observations. One necessary condition for our proposed scenario to work is that high-energy electrons resonate with the inertial range of the MHD turbulence and low-energy electrons resonate with the dissipation range of the MHD turbulence at the acceleration site, and the spectrum of the dissipation range ~k -2.7. A ~k -2.7 dissipation range spectrum is consistent with recent solar wind observations.

  17. ON THE SPECTRAL HARDENING AT ∼>300 keV IN SOLAR FLARES

    International Nuclear Information System (INIS)

    Li, G.; Kong, X.; Zank, G.; Chen, Y.

    2013-01-01

    It has long been noted that the spectra of observed continuum emissions in many solar flares are consistent with double power laws with a hardening at energies ∼>300 keV. It is now widely believed that at least in electron-dominated events, the hardening in the photon spectrum reflects an intrinsic hardening in the source electron spectrum. In this paper, we point out that a power-law spectrum of electrons with a hardening at high energies can be explained by the diffusive shock acceleration of electrons at a termination shock with a finite width. Our suggestion is based on an early analytical work by Drury et al., where the steady-state transport equation at a shock with a tanh profile was solved for a p-independent diffusion coefficient. Numerical simulations with a p-dependent diffusion coefficient show hardenings in the accelerated electron spectrum that are comparable with observations. One necessary condition for our proposed scenario to work is that high-energy electrons resonate with the inertial range of the MHD turbulence and low-energy electrons resonate with the dissipation range of the MHD turbulence at the acceleration site, and the spectrum of the dissipation range ∼k –2.7 . A ∼k –2.7 dissipation range spectrum is consistent with recent solar wind observations.

  18. Radiation hardened COTS-based 32-bit microprocessor

    International Nuclear Information System (INIS)

    Haddad, N.; Brown, R.; Cronauer, T.; Phan, H.

    1999-01-01

    A high performance radiation hardened 32-bit RISC microprocessor based upon a commercial single chip CPU has been developed. This paper presents the features of radiation hardened microprocessor, the methods used to radiation harden this device, the results of radiation testing, and shows that the RAD6000 is well-suited for the vast majority of space applications. (authors)

  19. 2D/3D Program work summary report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-09-01

    The 2D/3D Program was carried out by Germany, Japan and the United States to investigate the thermal-hydraulics of a PWR large-break LOCA. A contributory approach was utilized in which each country contributed significant effort to the program and all three countries shared the research results. Germany constructed and operated the Upper Plenum Test Facility (UPTF), and Japan constructed and operated the Cylindrical Core Test Facility (CCTF) and the Slab Core Test Facility (SCTF). The US contribution consisted of provision of advanced instrumentation to each of the three test facilities, and assessment of the TRAC computer code against the test results. Evaluations of the test results were carried out in all three countries. This report summarizes the 2D/3D Program in terms of the contributing efforts of the participants, and was prepared in a coordination among three countries. US and Germany have published the report as NUREG/IA-0126 and GRS-100, respectively. (author).

  20. 2D/3D Program work summary report

    International Nuclear Information System (INIS)

    1995-09-01

    The 2D/3D Program was carried out by Germany, Japan and the United States to investigate the thermal-hydraulics of a PWR large-break LOCA. A contributory approach was utilized in which each country contributed significant effort to the program and all three countries shared the research results. Germany constructed and operated the Upper Plenum Test Facility (UPTF), and Japan constructed and operated the Cylindrical Core Test Facility (CCTF) and the Slab Core Test Facility (SCTF). The US contribution consisted of provision of advanced instrumentation to each of the three test facilities, and assessment of the TRAC computer code against the test results. Evaluations of the test results were carried out in all three countries. This report summarizes the 2D/3D Program in terms of the contributing efforts of the participants, and was prepared in a coordination among three countries. US and Germany have published the report as NUREG/IA-0126 and GRS-100, respectively. (author)

  1. Indonesia's family planning program works toward self-sufficiency.

    Science.gov (United States)

    Kunii, C

    1989-07-01

    Started in 1970, the Indonesian Family Planning Program is doing very well. It is coordinated by the National Family Planning Coordinating Board (BKKBN). Many new acceptors are being enrolled daily. Its aim is to reduce to 1971 fertility rate of 50% in 1990. Strategy factors are listed. The following paper, "BKKBN and the Expanding Role of Private Sector Family Planning Services and Commercial Contraceptive Sales in Indonesia," by Dr. Haryono Suyono is introduced. Another article, "A breakthrough in Family Planning Promotional Strategy," by Mr. Sumarsono is also introduced. This article deals with the marketing aspect of Indonesia's family planning program.

  2. Towards a parsimonious program theory of return to work intervention.

    Science.gov (United States)

    Claudi Jensen, Anne Grete

    2013-01-01

    Presentation of a salutogenic theory of return to work (RTW). The study group include 118 unskilled Danish public employees and privately employed house-cleaners on sick leave due to musculoskeletal and/or common mental illnesses. Theory of RTW is discussed from a theoretical and empirical viewpoint, using baseline-data from an intervention study in a longitudinal, non-randomized study design with follow-up after one year. High work ability, strong social support from colleagues and over-commitment are the most important prognostic factors for RTW. An active coping style, high self-efficacy and Sense of Coherence (SOC) are found to increase RTW and high hostility and over-commitment to decrease RTW. Besides health elements in work ability are SOC, self-efficacy, social support and physical activity. Work ability and active coping mediate positive associations between RTW and health, and a negative association with stress. Work ability seems to express the intention to work decisive for RTW, reflecting the interpretation of the work/health situation based on comprehensibility, meaningfulness and manageability. It is influenced by the personal view of life, attitudes and interaction with the workplace. An ecological theory, integrating health promotion is proposed. A later paper will present the intervention study and further validation of the theory.

  3. Neutron energy spectrum influence on irradiation hardening and microstructural development of tungsten

    Energy Technology Data Exchange (ETDEWEB)

    Fukuda, Makoto, E-mail: makoto.fukuda@qse.tohoku.ac.jp [Tohoku University, Sendai, 980-8579 (Japan); Kiran Kumar, N.A.P.; Koyanagi, Takaaki; Garrison, Lauren M. [Oak Ridge National Laboratory, Oak Ridge, TN, 37831 (United States); Snead, Lance L. [Massachusetts Institute of Technology, Cambridge, MA, 02139 (United States); Katoh, Yutai [Oak Ridge National Laboratory, Oak Ridge, TN, 37831 (United States); Hasegawa, Akira [Tohoku University, Sendai, 980-8579 (Japan)

    2016-10-15

    Neutron irradiation to single crystal pure tungsten was performed in the mixed spectrum High Flux Isotope Reactor (HFIR). To investigate the influences of neutron energy spectrum, the microstructure and irradiation hardening were compared with previous data obtained from the irradiation campaigns in the mixed spectrum Japan Material Testing Reactor (JMTR) and the sodium-cooled fast reactor Joyo. The irradiation temperatures were in the range of ∼90–∼800 °C and fast neutron fluences were 0.02–9.00 × 10{sup 25} n/m{sup 2} (E > 0.1 MeV). Post irradiation evaluation included Vickers hardness measurements and transmission electron microscopy. The hardness and microstructure changes exhibited a clear dependence on the neutron energy spectrum. The hardness appeared to increase with increasing thermal neutron flux when fast fluence exceeds 1 × 10{sup 25} n/m{sup 2} (E > 0.1 MeV). Irradiation induced precipitates considered to be χ- and σ-phases were observed in samples irradiated to >1 × 10{sup 25} n/m{sup 2} (E > 0.1 MeV), which were pronounced at high dose and due to the very high thermal neutron flux of HFIR. Although the irradiation hardening mainly caused by defects clusters in a low dose regime, the transmutation-induced precipitation appeared to impose additional significant hardening of the tungsten. - Highlights: • The microstructure and irradiation hardening of single crystal pure W irradiated in HFIR was investigated. • The neutron energy spectrum influence was evaluated by comparing the HFIR results with previous work in Joyo and JMTR. • In the dose range up to ∼1 dpa, the neutron energy spectrum influence of irradiation hardening was not clear. • In the dose range above 1 dpa, the neutron energy influence on irradiation hardening and microstructural development was clearly observed. • The irradiation induced precipitates caused significant irradiation hardening of pure W irradiated in HFIR.

  4. Study of the mechanisms involved in the laser superficial hardening process of metallic alloys

    International Nuclear Information System (INIS)

    Silva, Edmara Marques Rodrigues da

    2001-01-01

    The laser superficial hardening process of a ferrous alloy (gray cast iron) and of an aluminum-silicon alloy was investigated in this work. These metallic alloys are used in the automobile industry for manufacturing cylinders and pistons, respectively. By application of individual pulses and single tracks, the involved mechanisms during the processing were studied. Variables such as energy density, power density, temporal width, beam diameter on the sample surface, atmosphere of the processing region, overlapping and scanning velocity. The hardened surface was characterized by optical and scanning electronic microscopy, dispersive energy microanalysis, X-ray mapping, X-ray diffraction, and measurements of roughness and Vickers microhardness. Depending on the processing parameters, it is possible to obtain different microstructures. The affected area of gray cast iron, can be hardened by remelting or transformation hardening (total or partial) if the reached temperature is higher or not that of melting temperature. Laser treatment originated new structures such as retained austenite, martensite and, occasionally, eutectic of cellular dendritic structure. Aluminum-silicon alloy does not have phase transformation in solid state, it can be hardened only by remelting. The increase of hardness is a function of the precipitation hardening process, which makes the silicon particles smaller and more disperse in the matrix. Maximal values of microhardness (700-1000 HV) were reached with the laser treatment in gray cast iron samples. The initial microhardness is of 242 HV. For aluminum-silicon alloy, the laser remelting increases the initial microhardness of 128 HV to the range of 160-320 HV. The found results give a new perspective for using the CLA/IPEN's laser in the heat treatment area. Besides providing a higher absorptivity to the materials, compared with the CO 2 laser, and optical fiber access, the superficial hardening with Nd:YAG laser, depending on the level of

  5. 'Feel better/work better' epitomizes employee fitness program.

    Science.gov (United States)

    Molidor, C

    1979-01-01

    It stands to reason that employees who feel better will take less time off because of illness and, consequently, improve their productivity. Rather than leave the health of their employees to chance, the Mercy Center for Health Care Services in Aurora, IL, put together a program that develops the total fitness of individual employees.

  6. Wider Opportunities for Women Nontraditional Work Programs: A Guide.

    Science.gov (United States)

    Wider Opportunities for Women, Inc., Washington, DC.

    Since 1970, Wider Opportunities for Women (WOW), in Washington, D.C., has conducted programs to train and place disadvantaged women in nontraditional jobs. The results have been record-breaking: high placement rates, high job retention rates, good starting salaries, and upward mobility for women who seemed doomed to a life of poverty and…

  7. 24 CFR 570.415 - Community Development Work Study Program.

    Science.gov (United States)

    2010-04-01

    ... planning, community management, public administration, public policy, urban economics, urban management... humanistic fields such as law, economics (except for urban economics), education and history. “Community... doctoral programs are ineligible. (iii) Must demonstrate an ability to maintain a satisfactory level of...

  8. Restricted working hours in Austrian residency programs : Survey results.

    Science.gov (United States)

    Bergmeister, Konstantin D; Aman, Martin; Podesser, Bruno K

    2018-04-27

    New regulations for working hours of medical doctors have been implemented in Austria based on the European directive 2003/88/EG, limiting on-duty working hours to 48 h per week. Clinical work is, therefore, substantially reduced compared to previous decades, and little is known on physician and students' opinions on this matter. We illustrate survey results concerning on-job training, its difficulties, and implications for restricted working hours. We conducted an internal survey among M.D. and Ph.D. students and medical staff members at the Medical University of Vienna using the MedCampus system (CAMPUSOnline, Graz, Austria) and SPSS (V.21, IBM Corp, Armonk, NY, USA). Participants were 36.5% staff members and 63.5% students. Students rated continuous education of physicians high at 9.19 ± 1.76 and staff members at 8.90 ± 2.48 on a 1-10 (1 unimportant, 10 most important) scale. Students rated limited time resources, while staff considered financial resources as the greatest challenge for in-hospital education. Overall, 28.85% thought that restricted working hours can positively influence education, while 19.04% thought the opposite and 52.11% were undecided. Considering the limited available time and financial resources, education of tomorrow's medical doctors remains an important but difficult task. While participants of our survey rated education as very important despite its many challenges, the opinions towards limited working hours were not as clear. Given that over 50% are still undecided whether reduced work hours may also positively influence medical education, it clearly presents an opportunity to include the next generations of physicians in this undertaking.

  9. idRHa+ProMod - Rail Hardening Control System

    International Nuclear Information System (INIS)

    Ferro, L

    2016-01-01

    idRHa+ProMod is the process control system developed by Primetals Technologies to foresee the thermo-mechanical evolution and micro-structural composition of rail steels subjected to slack quenching into idRHa+ Rail Hardening equipments in a simulation environment. This tool can be used both off-line or in-line, giving the user the chance to test and study the best cooling strategies or letting the automatic control system free to adjust the proper cooling recipe. Optimization criteria have been tailored in order to determine the best cooling conditions according to the metallurgical requirements imposed by the main rail standards and also taking into account the elastoplastic bending phenomena occurring during all stages of the head hardening process. The computational core of idRHa+ProMod is a thermal finite element procedure coupled with special algorithms developed to work out the main thermo-physical properties of steel, to predict the non-isothermal austenite decomposition into all the relevant phases and subsequently to evaluate the amount of latent heat of transformation released, the compound thermal expansion coefficient and the amount of plastic deformation in the material. Air mist and air blades boundary conditions have been carefully investigated by means of pilot plant tests aimed to study the jet impingement on rail surfaces and the cooling efficiency at all working conditions. Heat transfer coefficients have been further checked and adjusted directly on field during commissioning. idRHa+ is a trademark of Primetals Technologies Italy Srl (paper)

  10. idRHa+ProMod - Rail Hardening Control System

    Science.gov (United States)

    Ferro, L.

    2016-03-01

    idRHa+ProMod is the process control system developed by Primetals Technologies to foresee the thermo-mechanical evolution and micro-structural composition of rail steels subjected to slack quenching into idRHa+ Rail Hardening equipments in a simulation environment. This tool can be used both off-line or in-line, giving the user the chance to test and study the best cooling strategies or letting the automatic control system free to adjust the proper cooling recipe. Optimization criteria have been tailored in order to determine the best cooling conditions according to the metallurgical requirements imposed by the main rail standards and also taking into account the elastoplastic bending phenomena occurring during all stages of the head hardening process. The computational core of idRHa+ProMod is a thermal finite element procedure coupled with special algorithms developed to work out the main thermo-physical properties of steel, to predict the non-isothermal austenite decomposition into all the relevant phases and subsequently to evaluate the amount of latent heat of transformation released, the compound thermal expansion coefficient and the amount of plastic deformation in the material. Air mist and air blades boundary conditions have been carefully investigated by means of pilot plant tests aimed to study the jet impingement on rail surfaces and the cooling efficiency at all working conditions. Heat transfer coefficients have been further checked and adjusted directly on field during commissioning. idRHa+ is a trademark of Primetals Technologies Italy Srl

  11. BUSFET - A Novel Radiation-Hardened SOI Transistor

    International Nuclear Information System (INIS)

    Schwank, J.R.; Shaneyfelt, M.R.; Draper, B.L.; Dodd, P.E.

    1999-01-01

    The total-dose hardness of SOI technology is limited by radiation-induced charge trapping in gate, field, and SOI buried oxides. Charge trapping in the buried oxide can lead to back-channel leakage and makes hardening SOI transistors more challenging than hardening bulk-silicon transistors. Two avenues for hardening the back-channel are (1) to use specially prepared SOI buried oxides that reduce the net amount of trapped positive charge or (2) to design transistors that are less sensitive to the effects of trapped charge in the buried oxide. In this work, we propose a new partially-depleted SOI transistor structure that we call the BUSFET--Body Under Source FET. The BUSFET utilizes a shallow source and a deep drain. As a result, the silicon depletion region at the back channel caused by radiation-induced charge trapping in the buried oxide does not form a conducting path between source and drain. Thus, the BUSFET structure design can significantly reduce radiation-induced back-channel leakage without using specially prepared buried oxides. Total dose hardness is achieved without degrading the intrinsic SEU and dose rate hardness of SOI technology. The effectiveness of the BUSFET structure for reducing total-dose back-channel leakage depends on several variables, including the top silicon film thickness and doping concentration and the depth of the source. 3-D simulations show that for a doping concentration of 10 18 cm -3 and a source depth of 90 nm, a silicon film thickness of 180 nm is sufficient to almost completely eliminate radiation-induced back-channel leakage. However, for a doping concentration of 3x10 17 cm -3 , a thicker silicon film (300 nm) must be used

  12. FY 1999 annual work plan for infrastructure program WBS 6

    Energy Technology Data Exchange (ETDEWEB)

    Donley, C.D.

    1998-08-27

    The Fiscal Year (FY) 1999 DynCorp Annual Work Plan (AWP) relates DOE-RL work breakdown structure (WBS) to Cost Accounts and to Organizational Structure. Each Cost Account includes a workscope narrative and justification performance and service standards, goals, and deliverables. Basis of estimates are included within each Cost Account to demonstrate the relationship of budget to defined workscope. The FY 1999 AWP reflects the planning assumptions and initiatives that are included in the PHMC Strategic Plan for Infrastructure Optimization which was established in FY 1998. Development of the FY 1999 AWP was in accordance with a sequential series of events and efforts described in the Infrastructure Annual Work Planning and Budget Cycle which was developed and established in conjunction with the Strategic Plan. The Strategic Plan covers a rolling five year span of time and is updated at the start of each fiscal year as the beginning of the annual work planning and budget cycle for the following fiscal year. Accordingly the planning for the FY 1999 AWP began in January 1998. Also included in the annual work planning and budget cycle, and the basis for the budget in this AWP, is the development of a requirements-based budget.

  13. Case report: a work simulation program for a manual worker with a fracture injury.

    Science.gov (United States)

    Chan, Chi-Chung; Chow, Jonathan H.W.

    2000-01-01

    Work rehabilitation programs targeting different client groups are available in nearly all major hospital occupational therapy departments in Hong Kong. Clients receiving work rehabilitation are referred from various out-patient clinics and other occupational therapists. Those clients experience limitation in work after their injuries or diseases and plan to return to work after rehabilitation. Program objectives are 1) to assist clients to reach maximum work capacity as rapidly as possible 2) to ensure clients return to work safely 3) to improve clients' work readiness. This case report describes an individualized work simulation program at a general hospital in Hong Kong provided for a typical client who is preparing to return to his worker role. Specific job analysis, goals and program rationale for the client are discussed.

  14. Effects of the Indianapolis Vocational Intervention Program (IVIP) on defeatist beliefs, work motivation, and work outcomes in serious mental illness.

    Science.gov (United States)

    Mervis, Joshua E; Fiszdon, Joanna M; Lysaker, Paul H; Nienow, Tasha M; Mathews, Laura; Wardwell, Patricia; Petrik, Tammy; Thime, Warren; Choi, Jimmy

    2017-04-01

    Defeatist beliefs and amotivation are prominent obstacles in vocational rehabilitation for people with serious mental illnesses (SMI). The CBT-based Indianapolis Vocational Intervention Program (IVIP) was specifically designed to reduce defeatist beliefs related to work functioning. In the current study, we examined the impact of IVIP on defeatist beliefs and motivation for work, hypothesizing that IVIP would be associated with a reduction in defeatist beliefs and greater motivation for work. We also examined the effects of IVIP on these variables as well as work outcomes during a 12-month follow-up. Participants with SMI (n=64) enrolled in a four-month work therapy program were randomized to IVIP or a support therapy group (SG). Assessments were conducted at baseline, post-treatment (4months), and follow-up (1year). Compared to those in SG condition, individuals randomized to IVIP condition reported greater reductions in defeatist beliefs and greater motivation for work at follow-up, along with greater supported employment retention rates. Specifically treating and targeting negative expectations for work therapy improves outcomes, even once active supports of the IVIP program and work therapy are withdrawn. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Implementation of the thinking skills for work program in a psychosocial clubhouse.

    Science.gov (United States)

    McGurk, Susan R; Schiano, Diane; Mueser, Kim T; Wolfe, Rosemarie

    2010-01-01

    Cognitive remediation programs aimed at improving role functioning have been implemented in a variety of different mental health treatment settings, but not in psychosocial clubhouses. This study sought to determine the feasibility and preliminary outcomes of providing a cognitive remediation program (the Thinking Skills for Work program), developed and previously implemented in supported employment programs at mental health agencies, in a psychosocial club-house. Twenty-three members with a history of difficulties getting or keeping jobs, who were participating in a supported employment program at a psychosocial clubhouse, were enrolled in the Thinking Skills for Work program. A neurocognitive battery was administered at baseline and 3 months later after completion of the computer cognitive training component of the program. Hours of competitive work were tracked for the 2 years before enrollment and 2 years following enrollment. Other work-related activities (school, volunteer) were also tracked for 2 years following enrollment. Twenty-one members (91%) completed 6 or more computer cognitive training sessions. Participants demonstrated significant improvements on neurocognitive measures of processing speed, verbal learning and memory, and executive functions. Sixty percent of the members obtained a competitive job during the 2-year follow-up, and 74% were involved in some type of work-related activity. Participants worked significantly more competitive hours over the 2 years after joining the Thinking Skills for Work program than before. The findings support the feasibility and promise of implementing the Thinking Skills for Work program in the context of supported employment provided at psychosocial clubhouses.

  16. Romanian Physicists at CERN work for the Alice Program

    CERN Multimedia

    2007-01-01

    "For the past six years a team of Romanian scientists from the Institute of Nuclear Physics in Magurele, Romania, work as part of an international team of CERN to recreate the very first moments of the Universe, right after the Big Bang. The experiment was called Alice."(2 pages)

  17. ACHP | Working Together to Build a More Inclusive Preservation Program

    Science.gov (United States)

    experience in the architecture field, and received her Bachelor of Architecture from Cornell University. She buildings range in styles of neo-classical architecture to modern Brutalist. The project also highlights the transformation of Cleveland's downtown from a singularly business-centric to a multi-use live/work/play

  18. Two Back Stress Hardening Models in Rate Independent Rigid Plastic Deformation

    Science.gov (United States)

    Yun, Su-Jin

    In the present work, the constitutive relations based on the combination of two back stresses are developed using the Armstrong-Frederick, Phillips and Ziegler’s type hardening rules. Various evolutions of the kinematic hardening parameter can be obtained by means of a simple combination of back stress rate using the rule of mixtures. Thus, a wide range of plastic deformation behavior can be depicted depending on the dominant back stress evolution. The ultimate back stress is also determined for the present combined kinematic hardening models. Since a kinematic hardening rule is assumed in the finite deformation regime, the stress rate is co-rotated with respect to the spin of substructure obtained by incorporating the plastic spin concept. A comparison of the various co-rotational rates is also included. Assuming rigid plasticity, the continuum body consists of the elastic deformation zone and the plastic deformation zone to form a hybrid finite element formulation. Then, the plastic deformation behavior is investigated under various loading conditions with an assumption of the J2 deformation theory. The plastic deformation localization turns out to be strongly dependent on the description of back stress evolution and its associated hardening parameters. The analysis for the shear deformation with fixed boundaries is carried out to examine the deformation localization behavior and the evolution of state variables.

  19. Structural heredity influence upon principles of strain wave hardening

    Science.gov (United States)

    Kiricheck, A. V.; Barinov, S. V.; Yashin, A. V.

    2017-02-01

    It was established experimentally that by penetration of a strain wave through material hardened not only the technological modes of processing, but also a technological heredity - the direction of the fibers of the original macrostructure have an influence upon the diagram of microhardness. By penetration of the strain wave along fibers, the degree of hardening the material is less, however, a product is hardened throughout its entire section mainly along fibers. In the direction of the strain waves across fibers of the original structure of material, the degree of material hardening is much higher, the depth of the hardened layer with the degree of hardening not less than 50% makes at least 3 mm. It was found that under certain conditions the strain wave can completely change the original structure of the material. Thus, a heterogeneously hardened structure characterized by the interchange of harder and more viscous areas is formed, which is beneficial for assurance of high operational properties of material.

  20. Hydrogen embrittlement susceptibility of laser-hardened 4140 steel

    Energy Technology Data Exchange (ETDEWEB)

    Tsay, L.W.; Lin, Z.W. [Nat. Taiwan Ocean Univ., Keelung (Taiwan). Inst. of Mater. Eng.; Shiue, R.K. [Institute of Materials Sciences and Engineering, National Dong Hwa University, Hualien, Taiwan (Taiwan); Chen, C. [Institute of Materials Sciences and Engineering, National Taiwan University, Taipei, Taiwan (Taiwan)

    2000-10-15

    Slow strain rate tensile (SSRT) tests were performed to investigate the susceptibility to hydrogen embrittlement of laser-hardened AISI 4140 specimens in air, gaseous hydrogen and saturated H{sub 2}S solution. Experimental results indicated that round bar specimens with two parallel hardened bands on opposite sides along the loading axis (i.e. the PH specimens), exhibited a huge reduction in tensile ductility for all test environments. While circular-hardened (CH) specimens with 1 mm hardened depth and 6 mm wide within the gauge length were resistant to gaseous hydrogen embrittlement. However, fully hardened CH specimens became susceptible to hydrogen embrittlement for testing in air at a lower strain rate. The strength of CH specimens increased with decreasing the depth of hardened zones in a saturated H{sub 2}S solution. The premature failure of hardened zones in a susceptible environment caused the formation of brittle intergranular fracture and the decrease in tensile ductility. (orig.)

  1. Hardened Solar Array High Temperature Adhesive.

    Science.gov (United States)

    1981-04-01

    SHERWOOO. D SASIU.IS F3361S-0-C-201S UNCLASSI ED 1AC-SCG-IOOIIR AFVAL-TR-OL-201? NLm,,hinii EhhhEE11I1 AFWAL-TR-81- 2017 i : HARDENED SOLAR ARRAY D HIGH...Tg and as a consequence forms a film on the container and also precipitates as tacky waxlike particles, rather than the desired flocullated

  2. Hardening by means of ionising radiation

    International Nuclear Information System (INIS)

    Spoor, H.; Demmler, K.

    1979-01-01

    The polymerisable ethylic unsaturated mixture can be hardened by means of electron irradiation and used as a corrosion preventive layer. The mixture mainly consists of at least a di-olefinic unsaturated polyester, partial esters of polycarbonic acids, in particular the monoester of dicarbonic acids, with a copolymerizable C-C double bond, and mono-olefine unsaturated hydrocarbons, for example vinyl aromatics. The coatings exhibit good adhesion to the substrate, in particular to metal, and good flexibility. (DG) [de

  3. Work, eat and sleep : towards a healthy ageing at work program offshore

    NARCIS (Netherlands)

    Riethmeister, Vanessa; Brouwer, Sandra; van der Klink, Jac; Bültmann, Ute

    2016-01-01

    BACKGROUND: Health management tools need to be developed to foster healthy ageing at work and sustain employability of ageing work-forces. The objectives of this study were to 1) perform a needs assessment to identify the needs of offshore workers in the Dutch Continental Shelf with regard to

  4. GRAVITY PIPELINE TRANSPORT FOR HARDENING FILLING MIXTURES

    Directory of Open Access Journals (Sweden)

    Leonid KROUPNIK

    2015-12-01

    Full Text Available In underground mining of solid minerals becoming increasingly common development system with stowing hardening mixtures. In this case the natural ore array after it is replaced by an artificial excavation of solidified filling mixture consisting of binder, aggregates and water. Such a mixture is prepared on the surface on special stowing complexes and transported underground at special stowing pipelines. However, it is transported to the horizons of a few kilometers, which requires a sustainable mode of motion of such a mixture in the pipeline. Hardening stowing mixture changes its rheological characteristics over time, which complicates the calculation of the parameters of pipeline transportation. The article suggests a method of determining the initial parameters of such mixtures: the status coefficient, indicator of transportability, coefficient of hydrodynamic resistance to motion of the mixture. These indicators characterize the mixture in terms of the possibility to transport it through pipes. On the basis of these indicators is proposed methodology for calculating the parameters of pipeline transport hardening filling mixtures in drift mode when traffic on the horizontal part of the mixture under pressure column of the mixture in the vertical part of the backfill of the pipeline. This technique allows stable operation is guaranteed to provide pipeline transportation.

  5. Novel circuits for radiation hardened memories

    International Nuclear Information System (INIS)

    Haraszti, T.P.; Mento, R.P.; Moyer, N.E.; Grant, W.M.

    1992-01-01

    This paper reports on implementation of large storage semiconductor memories which combine radiation hardness with high packing density, operational speed, and low power dissipation and require both hardened circuit and hardened process technologies. Novel circuits, including orthogonal shuffle type of write-read arrays, error correction by weighted bidirectional codes and associative iterative repair circuits, are proposed for significant improvements of SRAMs' immunity against the effects of total dose and cosmic particle impacts. The implementation of the proposed circuit resulted in fault-tolerant 40-Mbit and 10-Mbit monolithic memories featuring a data rate of 120 MHz and power dissipation of 880 mW. These experimental serial-parallel memories were fabricated with a nonhardened standard CMOS processing technology, yet provided a total dose hardness of 1 Mrad and a projected SEU rate of 1 x 10 - 12 error/bit/day. Using radiation hardened processing improvements by factors of 10 to 100 are predicted in both total dose hardness and SEU rate

  6. The formation of structures and properties of carburized elements and hardened in different quenching medium

    International Nuclear Information System (INIS)

    Przylecka, M.; Gestwa, W.

    2003-01-01

    In work structure and selected properties of hardened carburized layers were introduced produced on chromium-manganese steel (16HG - 16CrMn5), after processes of gas carburizing (850 o C/1-10 h) and vacuum carburizing (950 o C/2 h) as well as direct hardening (center cooling: distillated water, Water polymer solution - polyglycol oxyalkylen, oil and gas-nitrogen) and tempering. Results of investigations permitted to affirm, that layer with structure martensite - retained austenite, as carbides - martensite - retained austenite produced in process of hardening applying cooling centre water polymer solution, the impact strength of element (at define thickness of carburized layer) give profitable, suitable hardness and microhardness as well as changes of microhardness on section in comparison to produced layers during cooling in water or oil and gas. (author)

  7. Microstructural evolution and strain hardening behavior of the cold-drawn austenitic stainless steels

    International Nuclear Information System (INIS)

    Choi, Jeom Yong; Jin, Won

    1998-01-01

    The strain induced α ' -martensite formation and the strain hardening behavior of metastable austenitic stainless steel during cold drawing have been investigated. The strain induced α ' -martensite nucleates mainly at the intersection of the mechanical twins rather than ε-martensite. It could be explained by the increase of stacking fault energy which arises from the heat generated during high speed drawing and, for AISI 304/Cu, the additional effect of Cu additions. The strain hardening behavior of austenitic stainless steel is strongly related to the microstructural evolution accompanied by strain induced α ' -martensite. The work hardening rates of cold-drawn 304 increased with increasing interstitial element(C,N) contents which affect the strength of the strain induced α ' -martensite

  8. Temperature Effects on the Tensile Properties of Precipitation-Hardened Al-Mg-Cu-Si Alloys

    Directory of Open Access Journals (Sweden)

    J.B. Ferguson

    2016-02-01

    Full Text Available Because the mechanical performance of precipitation-hardened alloys can be significantly altered with temperature changes, understanding and predicting the effects of temperatures on various mechanical properties for these alloys are important. In the present work, an analytical model has been developed to predict the elastic modulus, the yield stress, the failure stress, and the failure strain taking into consideration the effect of temperatures for precipitation-hardenable Al-Mg-Cu-Si Alloys (Al-A319 alloys. In addition, other important mechanical properties of Al-A319 alloys including the strain hardening exponent, the strength coefficient, and the ductility parameter can be estimated using the current model. It is demonstrated that the prediction results based on the proposed model are in good agreement with those obtained experimentally in Al-A319 alloys in the as-cast condition and after W and T7 heat treatments.

  9. 31 CFR 356.31 - How does the STRIPS program work?

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 2 2010-07-01 2010-07-01 false How does the STRIPS program work? 356.31 Section 356.31 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued...) Miscellaneous Provisions § 356.31 How does the STRIPS program work? (a) General. Notes or bonds may be “stripped...

  10. Play Therapy Training among School Psychology, Social Work, and School Counseling Graduate Training Programs

    Science.gov (United States)

    Pascarella, Christina Bechle

    2012-01-01

    This study examined play therapy training across the nation among school psychology, social work, and school counseling graduate training programs. It also compared current training to previous training among school psychology and school counseling programs. A random sample of trainers was selected from lists of graduate programs provided by…

  11. Security, Dignity, Caring Relationships, and Meaningful Work: Needs Motivating Participation in a Job-Training Program

    Science.gov (United States)

    Ayers, David F.; Miller-Dyce, Cherrel; Carlone, David

    2008-01-01

    Researchers asked 17 participants in a job-training program to describe their personal struggles following an economic restructuring. Examined through a critical theoretical lens, findings indicate that the learners enrolled in the program to reclaim security, dignity, meaningful work, and caring relationships. Program planners at community…

  12. Perceptions of self-esteem in a welfare-to-wellness-to-work program.

    Science.gov (United States)

    Martin, Carolyn Thompson; Keswick, Judith L; Crayton, Diane; Leveck, Paula

    2012-01-01

    The study investigates welfare recipients' perceptions of personal self-esteem in relationship with their participation in a welfare-to-wellness-to-work program. The cross-sectional, mixed-methods design examined a convenience sample of 33 participants who attended a welfare-to-wellness-to-work program called Work Wellness: The Basics that is based in an agency called Wellness Works!. A demographic survey, Rosenberg's Self-Esteem scale, and qualitative interviews were used. Even with normal self-esteem scores, the participants credited the program with decreasing negative thoughts and improving self-esteem. The themes identified include program, self-esteem, mental health, and domestic violence. Information about the benefits of a holistic wellness program and its relationship with self-reported enhanced self-esteem can be used to assist with health promotion, policy, and the development of innovative programs that assist with transition from public assistance. © 2011 Wiley Periodicals, Inc.

  13. Doctoral Study Programs in Social Work at HBCUs: Origin and Program Development

    Science.gov (United States)

    Aubrey, Hal; Jordan, Tina; Stevenson, Andre P.; Boss-Victoria, Rena; Haynes, James; Estreet, Anthony; Smith, Jahmaine; Cameron, Elijah; Williams, Quotasze

    2016-01-01

    Fisk University began the genesis of HBCU graduate programs in 1880. During the next fifty years, several other HBCUs established graduate programs. That group included Lincoln, Howard, and Morgan State. However, only Lincoln University established a PhD program. The primary goal of this paper is to provide a historical perspective regarding the…

  14. Effects of a work injury prevention program for housekeeping in the hotel industry.

    Science.gov (United States)

    Landers, Merrill; Maguire, Lynn

    2004-01-01

    The aim of this retrospective study was to determine the effectiveness of a work injury prevention program in the housekeeping department of a hotel. Studies have validated the use of different injury prevention strategies to decrease the incidence of work-related injuries. Few studies, however, have reported the efficacy of an on-site work injury prevention program by a physical therapist. In 1995, implementation of a work injury prevention program by a physical therapist to 50 housekeeping supervisors, 60 house persons and 340 guest room attendants at a large hotel began. This program included a detailed work risk analysis of the work environment, development of job descriptions, identification of injury-related problematic work situations, and implementation of a job specific supervisor-training program. Supervisor, house person and guest room attendant training was also conducted at the end of 1995 and the beginning of 1997. Data of injury reports in 1995, 1996, and 1997 were analyzed to determine the results of the program. There was a reduction in total injury claims, total medical expenses, total lost work time and total restricted duty time. These results demonstrate the cost effectiveness of implementing a work injury prevention program for housekeeping guest room attendants in the hotel industry. Copyright 2004 IOS Press

  15. Constitutive modeling of quench-hardenable boron steel with tailored properties

    NARCIS (Netherlands)

    Eller, Tom K.; Greve, Lars; Anders, Michael T.; Medricky, Miloslav; Hatscher, Ansgar; Meinders, Timo; van den Boogaard, Ton; Volk, W.

    2013-01-01

    In this work, a material model is presented that predicts the crash-relevant constitutive behavior of quench-hardenable boron steel 22MnB5 as function of material hardness. Three sets of sheets of 22MnB5 are heat treated such that their as-treated microstructures are close to fully martensitic,

  16. The Danish national return-to-work program

    DEFF Research Database (Denmark)

    Aust, Birgit; Helverskov, Trine; Nielsen, Maj Britt Dahl

    2012-01-01

    approximately 19 500 working-age adults on long-term sickness absence, regardless of reason for sickness absence or employment status. It consists of three core elements: (i) establishment of multidisciplinary RTW teams, (ii) introduction of standardized workability assessments and sickness absence management...... procedures, and (iii) a comprehensive training course for the RTW teams. The effect evaluation is based on a parallel group randomized trial and a stratified cluster controlled trial and focuses on register-based primary outcomes – duration of sickness absence and RTW – and questionnaire-based secondary...

  17. HIV/AIDS Course Content in CSWE-Accredited Social Work Programs: A Survey of Current Curricular Practices

    Science.gov (United States)

    Rowan, Diana; Shears, Jeffrey

    2011-01-01

    The authors surveyed program directors at all bachelor of social work and master of social work programs accredited by the Council on Social Work Education using an online tool that assessed whether and how their respective social work programs are covering content related to HIV/AIDS. Of the 650 program directors, 153 (24%) participated in the…

  18. Forum of stakeholder confidence - Phase II of program of work

    International Nuclear Information System (INIS)

    Le Bars, Yves

    2006-01-01

    The author welcomed the Forum for Stakeholder Confidence (FSC) participants and introduced the day's meetings that would investigate the possible contributions and conditions for RD and D to support stakeholder confidence. In his introductory remarks, Mr. Le Bars reviewed the intent of this topical discussion and its contribution to the Phase 2 Programme of Work for FSC. Observations were drawn from previous FSC work concerning the evolving requirements for stakeholder involvement that require a new culture within the organizations. It is recognized that each actor must respect certain values and abilities, and have the capacity to communicate, to learn from the public and to adapt. In particular, it was suggested that the role of the expert in the decision-making process has changed, and there is a need to restore credibility to the voice of experts to support the processes relating to radioactive waste management. Mr. Le Bars spoke about the changing role of the 'expert' and increasing demands from the public to be informed, active participants in decision-making processes. As societal expectations have evolved over the years, there is less willingness to give the expert the legitimacy to decide, or the expert working solely with the decision-maker. Rather, there are growing demands for public policies to be defined and implemented through decision-making processes that also invite stakeholder participation, as another important category of actors. Thus, the decision-making process can be viewed as now involving three parties: the public, the experts and decision-makers. Research must be positioned in this context. Research must be part of the process, structure, behaviour and debate. It is meant to be introduced in the process as contributor to the project definition, by providing scientific background. Further, it is best undertaken through an adaptive behaviour, carried out by institutions with a clearly defined and communicated role. In setting

  19. Health Prevention Program: the cornerstone for a safe work environment

    Energy Technology Data Exchange (ETDEWEB)

    Flores-Andrade, Augusto; Benalcazar, Fernando L. [EnCanEcuador S.A., Quito (Ecuador)

    2004-07-01

    EnCana in Ecuador is deeply committed through the sustainable development by minimizing and controlling hazards, while contributing to the well being of the people and protecting the environment of the communities where we operate, the health and safety of our employees, as well as preventing any loss and ensuring business continuity. To ensure a safe work environment for all our employees and Contractors, the Company has conducted a complete Risk Evaluation, considering: physical, biological, chemical, ergonomics and psychosocial factors. Based on this Map of Risks, the exposure level and the age of the employee, the Medical Department established four different routines of medical exams (pre-occupational and occupational), which are conducted on a regular two years basis, or even in a shorter period of time, if required. Additionally, medical exams are conducted when an employee is transferred to a different position. All employees have their own records, which document their medical shape when enrolled, at any time while working, and when the person leaves the Company. This allows diagramming the history of employees, the following information: X Axis (horizontal) Age of the employee when enrolled, years (chronological) and position when the exams are conducted. Y Axis (vertical) Capability in terms of percentage, of different organs and physiology (audiometric, ears, lungs, etc.). All this information is processed by the EHS Department, which in conjunction with other departments, plan improvement Safety measures to avoid the exposure of the employees to those factors above mentioned, minimizing potential losses and reducing dramatically costs of accidents and absenteeism. Exactly the same concept is being implemented with Contractors, which must also comply with these requirements. Follow-up of all recommendations is conducted on a regular basis by the Employees, Contractors and Management (Executive) EHS Committees. (author)

  20. On residual stresses and fatigue of laser hardened steels

    International Nuclear Information System (INIS)

    Lin, Ru.

    1992-01-01

    This thesis deals with studies on residual stresses and fatigue properties of laser-transformation hardened steels. Two types of specimens, cylinders and fatigue specimens were used in the studies. The cylinders, made of Swedish steels SS 2244 and SS 2258 which correspond to AISI 4140 and AISI 52100 respectively, were locally hardened by a single scan of laser beam in the longitudinal direction, with various laser parameters. Residual stress distributions across the hardened tracks were measured by means of X-ray diffraction. The origins of residual stresses were investigated and discussed. For the fatigue specimens, including smooth and notched types made of Swedish steels SS 2244, SS 2225 and SS 1572 (similar to AISI 4140, AISI 4130 and AISI 1035, respectively), laser hardening was carried out in the gauge section. The residual stress field induced by the hardening process and the fatigue properties by plane bending fatigue test were studied. In order to investigate the stability of the residual stress field, stress measurements were also made on specimens being loaded near the fatigue limits for over 10 7 cycles. Further the concept of local fatigue strength was employed to correlate quantitatively the effect of hardness and residual stress field on the fatigue limits. In addition a group of smooth specimens of SS 2244 was induction hardened and the hardening results were compared with the corresponding laser hardened ones in terms of residual stress and fatigue behaviour. It has been found that compressive stresses exist in the hardened zone of all the specimens studied. The laser hardening condition, the specimen and how the hardening is carried out can significantly affect the residual stress field. Laser hardening can greatly improve the fatigue properties by inducing a hardened and compressed surface layer. (112 refs.)(au)

  1. On residual stresses and fatigue of laser hardened steels

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Ru.

    1992-01-01

    This thesis deals with studies on residual stresses and fatigue properties of laser-transformation hardened steels. Two types of specimens, cylinders and fatigue specimens were used in the studies. The cylinders, made of Swedish steels SS 2244 and SS 2258 which correspond to AISI 4140 and AISI 52100 respectively, were locally hardened by a single scan of laser beam in the longitudinal direction, with various laser parameters. Residual stress distributions across the hardened tracks were measured by means of X-ray diffraction. The origins of residual stresses were investigated and discussed. For the fatigue specimens, including smooth and notched types made of Swedish steels SS 2244, SS 2225 and SS 1572 (similar to AISI 4140, AISI 4130 and AISI 1035, respectively), laser hardening was carried out in the gauge section. The residual stress field induced by the hardening process and the fatigue properties by plane bending fatigue test were studied. In order to investigate the stability of the residual stress field, stress measurements were also made on specimens being loaded near the fatigue limits for over 10[sup 7] cycles. Further the concept of local fatigue strength was employed to correlate quantitatively the effect of hardness and residual stress field on the fatigue limits. In addition a group of smooth specimens of SS 2244 was induction hardened and the hardening results were compared with the corresponding laser hardened ones in terms of residual stress and fatigue behaviour. It has been found that compressive stresses exist in the hardened zone of all the specimens studied. The laser hardening condition, the specimen and how the hardening is carried out can significantly affect the residual stress field. Laser hardening can greatly improve the fatigue properties by inducing a hardened and compressed surface layer. (112 refs.)(au).

  2. Plutonium working reference materials for the NDA PDP program

    International Nuclear Information System (INIS)

    Marshall, R.; Foley, M.; McCullough, L.; Vance, D.

    1995-01-01

    Sixty-three QC standards, termed Working Reference Materials (WRMs) are being fabricated at Los Alamos for the Non-destructive Waste Assay Performance Development Plan. The WRMs require Pu and Am distributed uniformly in a low density matrix. A silicone rubber matrix initially specified has been changed to a packed, diatomaceous earth (DE) matrix to facilitate Pu-DE uniformity and minimize gas generation and WRM pressurization. Uniformity and separation stability was demonstrated with iron powder-DE mixtures. To meet the rigorous quality objectives on the mass of Pu and Am for each WRM, a uniform, stable batch of PuO2 with relatively high Am-241 content was prepared by blending, calcining, and screening. Multiple sample analyses demonstrated the PuO2 to be highly uniform and established that tight Pu and Am assay and Pu isotopic analysis precision requirements were met. Test blends were prepared and tested to successfully demonstrate Pu uniformity, freedom from PuO2 clumping, and acceptable alpha-neutron generation rates. Blends of PuO2-DE were prepared individually for each WRM; all 63 blends have been prepared. After loading and packing the blends into zircalloy cylinders, the air atmosphere will be replaced with helium and end caps inserted and welded. Following decontamination and leak checking, the cylinders will be loaded into secondary zircalloy cylinders and sealed with welded end caps

  3. Do public works programs crowd-out pro-environmental behavior?

    DEFF Research Database (Denmark)

    Kahsay, Goytom Abraha; Kassie, Workineh Asmare; Beyene, Abebe Damte

    The Ethiopian food for work program typically induces forest conservation work. While economic outcomes have been studied before, little is known about the program’s environmental impact. We run a choice experiment among Ethiopian farmers eliciting preferences in a hypothetical afforestation...... program that mimics the Ethiopian food-for-work program. We find that introducing food incentives decreases willingness to participate in the program and participation rate increases with an increase in the proportion of individuals selected for food incentive. We also find that the crowding-out effect...... is stronger when food incentive recipients are selected based on income compared to lottery-based selection. Our data points to pro-social signaling as the most likely channel for the crowding-out effect. These results suggest that (1) food-for-work programs could have unintended negative environmental...

  4. Columbia River Basin Fish and Wildlife Program Work Plan for Fiscal Year 1988.

    Energy Technology Data Exchange (ETDEWEB)

    United States. Bonneville Power Administration; Northwest Power Planning Council (U.S.); Columbia Basin Fish and Wildlife Authority

    1987-10-01

    The FY 1988 Columbia River Basin Fish and Wildlife Program Work Plan (Work Plan) presents Bonneville Power Administration's plans for implementing the Columbia River Basin Fish and Wildlife Program (Program) in FY 1988. The Work Plan focuses on individual Action Items found in the amended Program for which Bonneville Power Administration (BPA) has determined it has authority and responsibility to implement. The FY 1988 Work Plan emphasizes continuation of 95 ongoing projects, most of which involve protection, mitigation, or enhancement of anadromous fishery resources. These continuing activities are summarized briefly by Program area: (1) mainstem passage; (2) artificial propagation; (3) natural propagation; (4) resident fish and wildlife; and (5) planning activities.

  5. Deep Drawing Simulation Of High And Ultrahigh Strength Steels Under Consideration Of Anisotropic Hardening

    International Nuclear Information System (INIS)

    Roll, Karl; Faust, Alexander; Kessler, Lutz

    2007-01-01

    In today's sheet metal forming simulation, most attention is paid to yield loci functions, which describe the anisotropy of the material in yielding. The coefficients, defining the shape of the yield locus in these functions are usually fitted at a certain level of plastic work and are then valid for the whole range of plastic deformation. Modern high and ultrahigh strength steels, especially those with induced plasticity, may often exhibit only a very small anisotropy in yielding, but a severe anisotropy in work hardening for different loading conditions. This behavior can not be described by fitting the yield locus at a specific value of plastic deformation. An approach to take into account the anisotropic hardening of sheet metals is to provide different yield curves for several loading conditions and expand the yield locus dependent on the current form of load. By doing this, one can use a comparatively simple yield locus, like that of Hill from 1948, because all anisotropy is given by the different hardening curves. For the commercial FEM code LS DYNA the material model MATFEM Generalized Yield is available as a user subroutine, which supports this approach. In this paper, forming simulation results of different yield loci are compared with experimental results. The simulations were carried out in LS-DYNA with the Barlat 89 and 2000 yield loci and isotropic hardening and with the GenYld model combining a Hill 48 yield locus and anisotropic hardening. The deep drawing experiments were conducted on a hydraulic press, measuring binder and punch forces. The deformation of the sheet was measured by optical grid analysis. A comparison of the simulated and measured plastic strains shows that using a model including anisotropic hardening can produce better results than the usage of a complex yield locus but isotropic hardening for the examined materials. This might be interesting for e.g. spring back simulations. By combining a simple yield locus with anisotropic

  6. An evaluation of a coal mining company's return to work program

    International Nuclear Information System (INIS)

    Allen, R.G.

    1990-01-01

    This study consolidates and evaluates information and data obtained from a coal mining company's return to work program called the Work Therapy Program. Organizational information and economic and statistical data were available for the study based on the company's records. Analysis of the data included descriptive statistics such as total injuries, the frequency rate of injuries, total days away from work due to injury, average days away per employee, and severity rates. A cost-benefit analysis was conducted to determine if the Program was economically beneficial to the company. Data from an opinion survey of the management at the mine where the Program was first instituted was used to determine the perceptions of mine management with respect to the Work Therapy Program. Conclusions were that the Work Therapy Program was economically beneficial to the Company and that the Program resulted in a significant reduction in compensable injuries. The Program did not significantly reduce days away from work due to mine injury. Perceptions of mine management were mostly positive

  7. The effect on work ability of a tailored ergonomic learning program

    DEFF Research Database (Denmark)

    Sell, Lea; Lund, Henrik; Holtermann, Andreas

    2016-01-01

    BACKGROUND: The physical working conditions and the musculoskeletal health of industrial workers have an effect on their work ability. OBJECTIVE: The paper evaluates the effectiveness of an ergonomic learning program focused on the development of low strain working techniques. The project...

  8. EFFECT OF HARDENING TIME ON DEFORMATION-STRENGTH INDICATORS OF CONCRETE FOR INJECTION WITH A TWO-STAGE EXPANSION DURING HARDENING IN WATER

    Directory of Open Access Journals (Sweden)

    Tatjana N. Zhilnikova

    2017-01-01

    Full Text Available Abstract. Objectives Concretes for injection with a two-stage expansion are a kind of selfstressing concrete obtained with the use of self-stressing cement.The aim of the work is to study the influence of the duration of aging on the porosity, strength and self-stress of concrete hardening in water, depending on the expansion value at the first stage. At the first stage, the compacted concrete mixture is expanded to ensure complete filling of the formwork space. At the second stage, the hardening concrete expands due to the formation of an increased amount of ettringite. This process is prolonged in time, with the amount of self-stress and strength dependant on the conditions of hardening. Methods  Experimental evaluation of self-stress, strength and porosity of concretes that are permanently hardened in water, under air-moist and air-dry conditions after different expansion at the first stage. The self-stress of cement stone is the result of superposition of two processes: the hardening of the structure due to hydration of silicates and its expansion as a result of hydration of calcium aluminates with the subsequent formation of ettringite. The magnitude of self-stress is determined by the ratio of these two processes. The self-stress of the cement stone changes in a manner similar to the change in its expansion. The stabilisation of expansion is accompanied by stabilisation of self-stress of cement stone. Results  The relationship of self-stress, strength and porosity of concrete for injection with a two-stage expansion on the duration and humidity conditions of hardening, taking into account the conditions of deformation limitation at the first stage, is revealed. Conclusion During prolonged hardening in an aqueous medium, self-stresses are reduced up to 25% with the exception of expansion at the first stage and up to 20% with an increase in volume up to 5% at the first stage. The increase in compressive strength is up to 28% relative to

  9. Laser transformation hardening effect on hardening zone features and surface hardness of tool steel AISI D2

    Directory of Open Access Journals (Sweden)

    D. Lesyk

    2017-06-01

    Full Text Available The relationship of technological input regimes of the laser transformation hardening on change the hardening depth, hardening width, and hardening angle, as well as surface hardness of the tool steel AISI D2 using multifactor experiment with elements of the analysis of variance and regression equations was determined. The laser transformation hardening process implemented by controlling the heating temperature using Nd:YAG fiber laser with scanner, pyrometer and proportional-integral-differential controller. The linear and quadratic regression models are developed, as well as response surface to determine the effect of the heating temperature and feed rate of the treated surface on the energy density of the laser beam, hardening depths, hardening width, hardening angle, and surface hardness are designed. The main effect on the energy density of the laser beam has a velocity laser treatment, on the other hand, the main effect on the geometrical parameters of the laser hardened zone and surface hardness has temperature heating are shown. The optimum magnitudes of the heating temperature (1270 °C and feed rate of the treated surface (90 mm/min for laser transformation hardening of the tool steel AISI D2 using fiber laser with scanner were defined.

  10. Faculty Experiences of Merger and Organizational Change in a Social Work Program.

    Science.gov (United States)

    Adedoyin, A Christson; Miller, Monte; Jackson, Mary S; Dodor, Bernice; Hall, Kristen

    2016-01-01

    Social work programs are experiencing unprecedented organizational changes due to budget cuts, dwindling resources, global, and technological challenges. However, there is limited information in the literature about the merger experiences of faculty in social work programs. On one hand undergoing merger and reorganization provides the opportunity to reorganize, reprioritize, re-assess, develop strategies, and explore previously untapped opportunities for social work programs. Conversely, merger experiences have caused frustration, intention to quit, confusion, and loss of professional identity for social work faculty. In this article the authors utilize a journaling method and sense-making approach of the merger experiences of some of the faculty members of a social work program in the United States. The authors suggest a framework to understand how the faculty confronted the challenges, overcame the pitfalls, and maximized the opportunities offered during the merger and organizational change process.

  11. Exploring the Unique Features of a First Nations Graduate-Level Social Work Program

    Directory of Open Access Journals (Sweden)

    Ralph C. Bodor

    2015-03-01

    Full Text Available Recently, a one-time cohort of graduate-level social work students completed a unique MSW program. The program was delivered in partnership between the Faculty of Social Work, University of Calgary and Blue Quills First Nations College and, of the twenty four graduates; twenty-one were of First Nations or Me´tis ancestry. The program honored traditional knowledge and ways of learning combined with a critical analysis of Western perspectives of social work knowledge. Strong fiscal resources enabled the program to establish a formal support network for the students and to support the development of Indigenous curriculum and programming that encouraged success for the students. The program was fundamentally different than urban on-campus programs while still maintaining graduate level accreditation requirements. This analysis of the program required the use of Indigenous Research Methodology to collect and create an understanding of the program. Instructors commented on the centered, empowered, balanced, and congruent students. The formal and informal, concrete and invisible supports to the students ensured the success of this program and this cohort of students. As one student commented, the program started in ceremony, ended in ceremony, and could not fail within the context ceremony.

  12. Subseabed Disposal Program Plan. Volume II. FY80 budget and subtask work plans

    International Nuclear Information System (INIS)

    1980-01-01

    This volume of the Subseabed Disposal Program Plan presents a breakdown of the master program structure by major activity. Each activity is described and accompanied by a specific cost plan schedule and a milestone plan. The costs have been compiled in the Cost Plan Schedules attached to each Subtask Work Plan. The FY 1980 budget for the Subseabed Disposal Program is summarized at the second level of the Work Breakdown Structure. The milestone plans for FY 80 are presented. The milestones can be changed only with the concurrence of the Sandia Subseabed Program Manager

  13. Coating compositions hardenable by ionization beams

    International Nuclear Information System (INIS)

    Chaudhari, D.; Haering, E.; Dobbelstein, A.; Hoselmann, W.

    1976-01-01

    Coating compositions hardenable by ionizing radiation are described which contain as binding agents a mixture of at least 1 unsaturated olefin compound containing urethane groups, and at least 1 further unsaturated olefin compound that may be copolymerized. The unsaturated olefin compound containing the urethane groups is a reaction product of a compound containing carboxylic acid groups and a compound containing at least 1 isocyanate group where the mixture of the two olefins may contain conventional additives of the lacquer industry. 6 claims, no drawings

  14. An Innovative Radiation Hardened CAM Architecture

    CERN Document Server

    Shojaii, Seyed Ruhollah; The ATLAS collaboration

    2018-01-01

    This article describes an innovative Content Addressable Memory (CAM) cell with radiation hardened (RH) architecture. The RH-CAM is designed in a commercial 28 nm CMOS technology. The circuit has been simulated in worst-case conditions, and the effects due to single particles have been analyzed by injecting a current pulse into a circuit node. The proposed architecture is suitable for on-time pattern recognition tasks in harsh environments, such as front-end electronics in hadron colliders and in space applications.

  15. Radiation-hardened nonvolatile MNOS RAM

    International Nuclear Information System (INIS)

    Wrobel, T.F.; Dodson, W.H.; Hash, G.L.; Jones, R.V.; Nasby, R.D.; Olson, R.J.

    1983-01-01

    A radiation hardened nonvolatile MNOS RAM is being developed at Sandia National Laboratories. The memory organization is 128 x 8 bits and utilizes two p-channel MNOS transistors per memory cell. The peripheral circuitry is constructed with CMOS metal gate and is processed with standard Sandia rad-hard processing techniques. The devices have memory retention after a dose-rate exposure of 1E12 rad(Si)/s, are functional after total dose exposure of 1E6 rad(Si), and are dose-rate upset resistant to levels of 7E8 rad(Si)/s

  16. Application of submerged induction hardening; Ekichu koshuha yakiire no jitsuyoka

    Energy Technology Data Exchange (ETDEWEB)

    Nishimori, Y; Nagai, Y; Amii, Y [Mazda Motor Corp., Hiroshima (Japan); Tanaka, Y [Netsuren Co. Ltd., Tokyo (Japan); Mizuma, T [Toyo Advanced Technologies Co. Ltd., Hiroshima (Japan)

    1997-10-01

    As a cost-cutting measure, the linerless diesel engine was adopted by applying submerged induction hardening process which can harden partial inner surface of cylinder block bore. In applying this process, (1) development of induction coil which can form any shape of quenched pattern and (2) the development of machining technology which can hone precisely the distorted bore after quenching, were important. With these improvements, submerged Induction hardening was made practical. 1 ref., 11 figs.

  17. Hardening device, by inserts, of electronic component against radiation

    International Nuclear Information System (INIS)

    Val, C.

    1987-01-01

    The hardening device includes at least two materials, one with high atomic number with respect to the other. One of these materials is set as inserts in a layer of the other material. The hardening device is then made by stacking of such layers, the insert density varying from one layer to the other, making thus vary the atomic number resulting from the hardening device along its thickness, following a predefined law [fr

  18. Investigation of srawberry hardening in low temperatures in vitro

    OpenAIRE

    Lukoševičiūtė, Vanda; Rugienius, Rytis; Kavaliauskaitė, Danguolė

    2007-01-01

    Cold resistance of different strawberry varieties in vitro and ability to retain hardening after defrosting and repeated hardening. Phytohormons – gibberellin and abscisic acid added in the growing medium were investigated in Horticulture plant genetic and biotechnology department of LIH. We tried to model common conditions in temperate zone when freeze-thaw cycles often occur during wintertime. For investigation in vitro strawberries for the first time hardened in light at the temperature of...

  19. Configurable Radiation Hardened High Speed Isolated Interface ASIC, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — NVE Corporation will design and build an innovative, low cost, flexible, configurable, radiation hardened, galvanically isolated, interface ASIC chip set that will...

  20. 07051 Working Group Outcomes -- Programming Paradigms for the Web: Web Programming and Web Services

    OpenAIRE

    Hull, Richard; Thiemann, Peter; Wadler, Philip

    2007-01-01

    Participants in the seminar broke into groups on ``Patterns and Paradigms'' for web programming, ``Web Services,'' ``Data on the Web,'' ``Software Engineering'' and ``Security.'' Here we give the raw notes recorded during these sessions.

  1. Social Policy in Social Work PhD Programs in the United States

    Science.gov (United States)

    Lightfoot, Elizabeth; Gal, John; Weiss-Gal, Idit

    2018-01-01

    While there has been a long-standing concern about the role of policy within social work education and social work practice, most of the emphasis has been on social work education at the BSW and MSW levels. This article examines policy education at the PhD level. It first explores how policy is taught in social work PhD programs in the United…

  2. Investigation of selective oxidation in bake hardenable steel

    International Nuclear Information System (INIS)

    Madeira, Laureanny; Lins, Vanessa Cunha Freitas; Faria, Guilherme Augusto de; Guimaraes, Juliana Porto; Alvarenga, Evandro de Azevedo; Vilela, Jose Mario Carneiro

    2010-01-01

    The present work aims to characterize a steel bake hardenable (BH), annealed in three different dew points (-60°C, -30°C and 0°C), as the occurrence of selective oxidation, using the techniques of X-ray photo electronic spectroscopy (XPS), glow discharge optical emission spectroscopy (GDOES) and atomic force microscopy (AFM). The analysis by XPS showed that the alloying elements oxidized at different intensities for each dew point. Analysis by GDOES revealed that the surface and subsurface concentrations of these elements also varied with the dew point. The AFM images revealed that the size and shape of the oxides were different for each dew point. At the dew points of -30°C and -60°C the formation of oxides was local, while at 0°C the growth of oxides occurred uniform y on the surface of steels. (author)

  3. Effects of kinematic hardening rules on thermal ratchetting analysis of cylinders subjected to cyclically moving temperature distribution

    International Nuclear Information System (INIS)

    Ohno, N.; Kobayashi, M.

    1995-01-01

    In the present work, thermal ratchetting in a cylinder subjected to a cyclically moving temperature front (i.e. liquid surface induced thermal ratchetting) was analyzed by implementing in a finite element method the four kinds of plasticity models with different kinematic hardening rules. The following findings were thus obtained concerning effects of the kinematic hardening rules on the analysis. (1) If transition nonlinear hardening after yielding is disregarded, the thermal ratchetting becomes significant, as seen in the results of the PP and LKH models. Especially the PP model, which does not express any strain hardening, predicts steady development of the thermal ratchetting. (2) If significant mechanical ratchetting is allowed in the modeling of kinematic hardening, the thermal ratchetting becomes marked, as seen in the results of the AF model. (3) Model dependence of the thermal ratchetting is more noticeable when the difference of temperature at the temperature front, ΔT, is smaller. (4) The OW model makes the thermal ratchetting stop at a smaller number of cycles when ΔT is smaller. On the other hand, the LKH and AF models allow that the thermal ratchetting to develop more constantly when ΔT is smaller. As seen from the above findings, the analysis of liquid surface induced thermal ratchetting has great dependence on the kinematic hardening rules employed. Especially the PP model, which has been used often to analyze the thermal ratchetting so far, gives too large development of the thermal ratchetting. Thus we may say that in order to improve the analysis it is necessary to use an appropriate kinematic hardening model which is capable of expressing appropriately both mechanical ratchetting and transient nonlinear hardening after yielding. (author)

  4. The projects of skunk works 75 years of Lockheed Martin's advanced development programs

    CERN Document Server

    Pace, Steve

    2016-01-01

    The Projects of Skunk Works examines 75 years of Lockheed Martin's advanced development programs, from jet fighters to missiles, heavy-lift helicopters, a lighter-than-air ship, drones, and a stealth boat.

  5. Induction surface hardening of hard coated steels

    Energy Technology Data Exchange (ETDEWEB)

    Pantleon, K.; Kessler, O.; Hoffann, F.; Mayr, P. [Stiftung Inst. fuer Werkstofftechnik, Bremen (Germany)

    1999-11-01

    The properties of hard coatings deposited using CVD processes are usually excellent. However, high deposition temperatures negatively influence the substrate properties, especially in the case of low alloyed steels. Therefore, a subsequent heat treatment is necessary to restore the properties of steel substrates. Here, induction surface hardening is used as a method of heat treatment after the deposition of TiN hard coatings on AISI 4140 (DIN42CrMo4) substrates. The influences of the heat treatment on both the coating and the substrate properties are discussed in relation to the parameters of induction heating. Thereby, the heating time, heating atmosphere and the power input into the coating-substrate compounds are varied. As a result of induction surface hardening, the properties of the substrates are improved without losing good coating properties. High hardness values in the substrate near the interface allow the AISI 4140 substrates to support TiN hard coatings very well. Consequently, higher critical loads are measured in scratch tests after the heat treatment. Also, compressive residual stresses in the substrate are generated. In addition, only a very low distortion appears. (orig.)

  6. Influence of Cultivar on the Postharvest Hardening of Trifoliate Yam (Dioscorea dumetorum Tubers

    Directory of Open Access Journals (Sweden)

    Christian Siadjeu

    2016-01-01

    Full Text Available The influence of cultivar on the postharvest hardening of Dioscorea dumetorum tubers was assessed. 32 cultivars of D. dumetorum tubers were planted in April 2014, harvested at physiological maturity, and stored under prevailing tropical ambient conditions (19–28°C, 60–85% RH for 0, 5, 14, 21, and 28 days. Samples were evaluated for cooked hardness. Results showed that one cultivar, Ibo sweet 3, was not affected by the hardening phenomenon. The remaining 31 were all subject to the hardening phenomenon at different degree. Cooked hardness increased more rapidly in cultivars with many roots on the tuber surface compared to cultivars with few roots on the tuber surface. When both the characteristics flesh colour and number of roots on tuber surface were associated, cooked hardness in cultivars with yellow flesh and many roots increased more rapidly than in cultivars with white flesh and many roots, whereas cooked hardness in cultivars with yellow flesh and few roots increased more slowly than in cultivars with white flesh and few roots. Accessions collected in high altitude increased more rapidly compared to accessions collected in low altitude. The cultivar Ibo sweet 3 identified in this study could provide important information for breeding program of D. dumetorum against postharvest hardening phenomenon.

  7. Welfare to Work: Effectiveness of Tribal JOBS Programs Unknown. Briefing Report to Congressional Committees.

    Science.gov (United States)

    General Accounting Office, Washington, DC. Div. of Human Resources.

    This report presents the results of a study of the Job Opportunities and Basic Skills Training (JOBS) programs operated by Indian tribes and Alaska Native organizations. Congress established the JOBS program to give recipients of Aid to Families with Dependent Children (AFDC) the education, training, work experience, and supportive services they…

  8. Benefits and Challenges of Service-Learning in Baccalaureate Social Work Programs

    Science.gov (United States)

    Schelbe, Lisa; Petracchi, Helen E.; Weaver, Addie

    2014-01-01

    Service-learning is a pedagogical approach that integrates students' classroom instruction with community experience. This article discusses qualitative results from a national survey examining service-learning in Council on Social Work Education--accredited baccalaureate programs. Almost 80% of the 202 program respondents required…

  9. Cooperative Work-Study Programs in Vocational Rehabilitation: Results of a National Survey.

    Science.gov (United States)

    Bullis, Michael; Foss, Gilbert

    1983-01-01

    Conducted a national survey of vocational rehabilitation agencies (N=42) to determine the present status of cooperative work study programs serving mentally retarded secondary students. Results documented a decrease both in formal programs and number of students served. (Author/JAC)

  10. Development of structure design program for venturi scrubber working at self-priming mode

    International Nuclear Information System (INIS)

    Wang Meng; Sun Zhongning; Gu Haifeng

    2012-01-01

    A structure design program was developed for Venturi scrubber working at the self-priming mode. This program proposed a complete logic for thermal parameters calculation and structure design of the throat. A revised calculation for resistance relationship was carried out based on experimental study. The relative error between revised results and experimental values is within 8.6%. (authors)

  11. THE DEVELOPMENT OF A WORK ORIENTATION PROGRAM FOR HOME ECONOMICS RELATED OCCUPATIONS, 1964-1966.

    Science.gov (United States)

    FETTERMAN, ELSIE

    THE PURPOSE OF THIS STUDY, WHICH IS A SUMMARY OF A DOCTORAL DISSERTATION, WAS TO DEVELOP A WORK ORIENTATION PROGRAM FOR HOME ECONOMICS-RELATED OCCUPATIONS IN CONNECTICUT. QUESTIONNAIRES WERE SENT TO 43 TEACHERS OF SUCH PROGRAMS IN THE UNITED STATES AND ALL RESPONDED, GIVING INFORMATION ABOUT THEIR OBJECTIVES, COURSES, TEACHERS' BACKGROUNDS,…

  12. Work management administration FY 1995 site support program plan WBS 6.2

    Energy Technology Data Exchange (ETDEWEB)

    Hale, N.S.

    1994-09-01

    Westinghouse Hanford Company`s (WHC) near-term vision is to implement a Site-wide work management program that is consistent from one facility to the other, and can realize workforce efficiencies, minimum down time, and familiarization with facilities uniqueness. Additionally, consistent Hanford Site work management processes can produce meaningful information to be shared complex-wide as the US Department of Energy (DOE) cleans up facilities Site-wide. It is the mission of the WHC Work Management Administration Program to provide guidance and program direction on how to implement consistent and effective work management across the Hanford Site that comply with the DOE and other regulatory requirements. This report describes the steps needed to implement a work management plan at Hanford.

  13. Weaving networks of responsibility: community work in development programs in rural Malawi.

    Science.gov (United States)

    Rosenthal, Anat

    2012-01-01

    The need to cope with the impact of the AIDS epidemic on communities in Africa has resulted in the emergence of numerous community health and development programs. Initiated by governments, international nongovernmental organizations (NGOs), and local organizations, such programs target local communities with the goal of building care and support mechanisms in the local level. Based on ethnographic field research in rural Malawi, and drawing from the cross-disciplinary debate on development work, the article explores the work of an NGO offering health and care programs to orphans and vulnerable children. Through analyzing the organization's scope of work, the article demonstrates how the NGO acts to structure local social networks as instruments of care and offers a new reading of the role of NGOs in which the limitations of development work and the work of NGOs are understood within their local context and not only in the context of broad cultural critique.

  14. Strategies in disability management. Corporate disability management programs implemented at the work site.

    Science.gov (United States)

    Kalina, C M

    1999-10-30

    Managers are challenged to demonstrate all programs as economically essential to the business, generating an appreciable return on investment. Further challenge exists to blend and integrate clinical and business objectives in program development. Disability management programs must be viewed as economically essential to the financial success of the business to assure management support for clinical interventions and return-to-work strategies essential for a successful program. This paper discusses a disability management program integrating clinical and business goals and objectives in return-to-work strategies to effect positive clinical, social-cultural, and business results. Clinical, educational, social, and economic challenges in the development, implementation, and continued management of a disability program at a large corporation with multiple global work sites are defined. Continued discussion addresses the effective clinical interventions and educational strategies utilized successfully within the workplace environment in response to each defined challenge. A multiple disciplinary team approach, clinical and business outcome measures, and quality assurance indicators are discussed as major program components. This article discusses a successful program approach focusing on business process and methodology. These parameters are used to link resources to strategy, developing a product for implementing and managing a program demonstrating economic value added through effective clinical medical case management.

  15. Health status of people with work-related musculoskeletal disorders in return to work programs: a Malaysian study.

    Science.gov (United States)

    Murad, Mohd Suleiman; O'Brien, Lisa; Farnworth, Louise; Chien, Chi-Wen

    2013-07-01

    This study examined the health status of injured workers with musculoskeletal disorders enrolled in the Malaysian Return to Work (RTW) program. The 102 participants were categorized into three RTW groups: Off-work (n = 30, 29.4%), Re-entry (n = 44, 43.1%), and Maintenance (n = 28, 27.5%). Overall health status, as measured by the SF-36 version 2, of the workers exhibited below average compared to the internationally established normative population, with their physical health component summary rated lower than mental health. Across the different groups, significant differences were found in role-physical, vitality, bodily pain, general health, and mental health. However, the mean values of these variables were higher in the Maintenance group and were found significant. The current health status of injured workers at Off-work and Re-entry phases was significantly low and warranted to be improved by involving other health professionals such as occupational therapists, ergonomists, and psychologists.

  16. Rural Student Vocational Program (RSVP) [and] Housing Guide for Parents and Students [and] Work Supervisor's Guide.

    Science.gov (United States)

    Rural Student Vocational Program, Wasilla, AK.

    The purpose of the Rural Student Vocational Program (RSVP) is to provide rural high school vocational students with work and other experiences related to their career objective. Students from outlying schools travel to Anchorage, Fairbanks, or Juneau (Alaska) to participate in two weeks of work experience with cooperating agencies and businesses.…

  17. Elements of Success: WorkReady Philadelphia Program Year 2011-2012 Report

    Science.gov (United States)

    Philadelphia Youth Network, 2012

    2012-01-01

    What does it take to deliver WorkReady Philadelphia's high-quality career-connected programming? In short, it's all about the "elements"--those essential components of the system that combine to produce success for young people. This 2011-12 WorkReady report reinforces this theme by using visual aspects of the "Periodic Table of…

  18. Bidding for the unemployed: an application of mechanism design to welfare-to-work programs

    NARCIS (Netherlands)

    Onderstal, S.

    2009-01-01

    This paper applies the theory of mechanism design to welfare-to-work programs. When procuring welfare-to-work projects to employment service providers, governments face the problems of adverse selection (the winning provider is not the most efficient one) and moral hazard (the winning provider

  19. Bidding for the unemployed: an application of mechanism design to welfare-to-work programs

    NARCIS (Netherlands)

    Onderstal, S.

    2007-01-01

    This paper applies the theory of mechanism design to welfare-to-work programs. When procuring welfare-to-work projects to employment service providers, governments face the problems of adverse selection (the winning provider is not the most efficient one) and moral hazard (the winning provider

  20. Effect of hardening on the crack growth rate of austenitic stainless steels in primary PWR conditions

    International Nuclear Information System (INIS)

    Castano, M.L.; Garcia, M.S.; Diego, G. de; Gomez-Briceno, D.; Francia, L.

    2002-01-01

    Intergranular cracking of non-sensitized materials, found in light water reactor (LWR) components exposed to neutron radiation, has been attributed to Irradiation Assisted Stress Corrosion Cracking (IASCC). Cracking of baffle former bolts, fabricated of AISI-316L and AISI-347, have been reported in some Europeans and US PWR plants. Examinations of removed bolts indicate the intergranular cracking characteristics can be associated with IASCC phenomena. Neutron radiation produce critical modifications of the microstructure and microchemical of stainless steels such hardening due to irradiation and Radiation Induce Segregation (RIS) at grain boundaries, among others. Chromium depletion at grain boundary due to RIS seems to justify the intergranular cracking of irradiated materials, both in plant and in lab tests, at high electrochemical corrosion potential (BWR-NWC environments), but it is not enough to explain cracking at low corrosion potential (BWR-HWC and PWR environments). In these latter conditions, hardening is considered a possible additional mechanism to explain the behavior of irradiated material. Radiation Hardening can be simulated in non irradiated material by mechanical deformation. Although some differences exists in the types of defects produced by radiation and mechanical deformation, it is accepted that the study of the stress corrosion behavior of unirradiated austenitic steels with different hardening levels would contribute to the understanding of IASCC mechanism. In order to evaluate the influence of hardening on the stress corrosion susceptibility of austenitic steels, crack growth rate tests with 316L and 347 stainless steels with nominal yield strengths from 500 to 900 MPa, produced by cold work are being carried out at 340 deg C in PWR conditions. Preliminary results indicate that crack propagation was obtained in the 316Lss and 347ss cold worked, even with a yield strength of 550 MPa. (authors)

  1. A brief review of cavity swelling and hardening in irradiated copper and copper alloys

    International Nuclear Information System (INIS)

    Zinkle, S.J.

    1990-01-01

    The literature on radiation-induced swelling and hardening in copper and its alloy is reviewed. Void formation does not occur during irradiation of copper unless suitable impurity atoms such as oxygen or helium are present. Void formation occurs for neutron irradiation temperatures of 180 to 550 degree C, with peak swelling occurring at ∼320 degree C for irradiation at a damage rate of 2 x 10 -7 dpa/s. The post-transient swelling rate has been measured to be ∼0.5%/dpa at temperatures near 400 degree C. Dispersion-strengthened copper has been found to be very resistant to void swelling due to the high sink density associated with the dispersion-stabilized dislocation structure. Irradiation of copper at temperatures below 400 degree C generally causes an increase in strength due to the formation of defect clusters which inhibit dislocation motion. The radiation hardening can be adequately described by Seeger's dispersed barrier model, with a barrier strength for small defect clusters of α ∼ 0.2. The radiation hardening apparently saturates for fluences greater than ∼10 24 n/m 2 during irradiation at room temperature due to a saturation of the defect cluster density. Grain boundaries can modify the hardening behavior by blocking the transmission of dislocation slip bands, leading to a radiation- modified Hall-Petch relation between yield strength and grain size. Radiation-enhanced recrystallization can lead to softening of cold-worked copper alloys at temperatures above 300 degree C

  2. Bake hardening of ultra-fine grained low carbon steel produced by constrained groove pressing

    International Nuclear Information System (INIS)

    Alihosseini, H.; Dehghani, K.

    2012-01-01

    Highlights: ► BH of UFG low carbon steel sheets was studied. ► Three passes of CGP are used for producing of UFG sheets. ► Maximum BH was achieved to the UFG specimen pre-strained 8% by baking at 250 °C. - Abstract: In the present work, the bake hardening of ultra-fine grained low carbon steel was compared with that of its coarse-grain counterpart. The ultra-fine grained sheets were produced by applying three passes of constrained groove pressing resulting the grains of 260–270 nm. The microstructure of ultra-fine grain specimens were characterized using electron back-scatter diffraction technique. Then, the bake hardenability of ultra-fine grain and coarse-grain samples were compared by pre-straining to 4, 6 and 8% followed by baking at 150 °C and 250 °C for 20 min. The results show that in case of baking at 250 °C, there was an increase about 108%, 93%, and 72% in the bake hardening for 4%, 6% and 8% pre-strain, respectively. As for baking at 150 °C, these values were 170%, 168%, and 100%, respectively for 4%, 6% and 8% pre-strain. The maximum in bake hardenability (103 MPa) and final yield stress (563 MPa) were pertaining to the ultra-fine grain specimen pre-strained 8% followed by baking at 250 °C.

  3. Microstructural and Mechanical Study of Press Hardening of Thick Boron Steel Sheet

    Science.gov (United States)

    Pujante, J.; Garcia-Llamas, E.; Golling, S.; Casellas, D.

    2017-09-01

    Press hardening has become a staple in the production of automotive safety components, due to the combination of high mechanical properties and form complexity it offers. However, the use of press hardened components has not spread to the truck industry despite the advantages it confers, namely affordable weight reduction without the use of exotic materials, would be extremely attractive for this sector. The main reason for this is that application of press hardened components in trucks implies adapting the process to the manufacture of thick sheet metal. This introduces an additional layer of complexity, mainly due to the thermal gradients inside the material resulting in though-thickness differences in austenitization and cooling, potentially resulting in complex microstructure and gradient of mechanical properties. This work presents a preliminary study on the press hardening of thick boron steel sheet. First of all, the evolution of the sheet metal during austenitization is studied by means of dilatometry tests and by analysing the effect of furnace dwell time on grain size. Afterwards, material cooled using different cooling strategies, and therefore different effective cooling rates, is studied in terms of microstructure and mechanical properties. Initial results from finite element simulation are compared to experimental results, focusing on the phase composition in through thickness direction. Results show that industrial-equivalent cooling conditions do not lead to gradient microstructures, even in extreme scenarios involving asymmetrical cooling.

  4. Characterization and Strain-Hardening Behavior of Friction Stir-Welded Ferritic Stainless Steel

    Science.gov (United States)

    Sharma, Gaurav; Dwivedi, Dheerendra Kumar; Jain, Pramod Kumar

    2017-12-01

    In this study, friction stir-welded joint of 3-mm-thick plates of 409 ferritic stainless steel (FSS) was characterized in light of microstructure, x-ray diffraction analysis, hardness, tensile strength, ductility, corrosion and work hardening properties. The FSW joint made of ferritic stainless steel comprises of three distinct regions including the base metal. In stir zone highly refined ferrite grains with martensite and some carbide precipitates at the grain boundaries were observed. X-ray diffraction analysis also revealed precipitation of Cr23C6 and martensite formation in heat-affected zone and stir zone. In tensile testing of the transverse weld samples, the failure eventuated within the gauge length of the specimen from the base metal region having tensile properties overmatched to the as-received base metal. The tensile strength and elongation of the longitudinal (all weld) sample were found to be 1014 MPa and 9.47%, respectively. However, in potentiodynamic polarization test, the corrosion current density of the stir zone was highest among all the three zones. The strain-hardening exponent for base metal, transverse and longitudinal (all weld) weld samples was calculated using various equations. Both the transverse and longitudinal weld samples exhibited higher strain-hardening exponents as compared to the as-received base metal. In Kocks-Mecking plots for the base metal and weld samples at least two stages of strain hardening were observed.

  5. Environmental hardening of a mobile-manipulator system for nuclear environments

    International Nuclear Information System (INIS)

    Jones, S.L.; Cable, T.; Tulenko, J.S.; Toshkov, S.; Sias, F.R. Jr.

    1993-01-01

    This research report discusses the radiation hardening of a commercially available mobile robot, the REMOTEC ANDROS. This hardening effort is culminating in the availability of a megarad hardened mobile platform to access areas in nuclear facilities with extremely high levels of radiation (0.1 to 1 Mrad). These radiation levels may be encountered both during routine repair and monitoring activities and accident situations. The project has completed a phase-I U.S. Department of Energy Small Business Innovative Research contract and is now in a phase-II effort with completion scheduled in early 1995. The research involves the evaluation of the material and electrical components of an ANDROS robot to determine the anticipated radiation hardness of the current production version and evaluation of the components that must be replaced or modified to harden the system to higher radiation levels. The work being reported is based on an evaluation of the complete list of all electronic, electrical, and mechanical parts used in the robot and includes initial experimental radiation evaluations performed at the University of Florida

  6. Environmental hardening of robots for nuclear maintenance and surveillance tasks

    International Nuclear Information System (INIS)

    Hintenlang, D.E.; Tulenko, J.S.; Wheeler, R.; Roy, T.

    1990-01-01

    The University of Florida, in cooperation with the Universities of Texas, Tennessee, and Michigan and Oak Ridge National Laboratory, is developing an advanced robotic system for the US Department of Energy under the University Program for Robotics for Advanced Reactors. As part of this program, the University of Florida has been pursuing the development of environmentally hardened components so that autonomous robotic systems can successfully carry out their tasks under the most extreme expected environmental conditions. This requirement means that the designed robotic system with its onboard computer-based intelligence must be able to successfully complete tasks in toxic, radioactive, wet, temperature extremes, and other physically impairing environments. As part of this program, a study was carried out to determine the environmental conditions that should be set as the design criteria for robotic systems to maintain reasonable operations for nuclear plants in the course of maintenance, testing, and surveillance under all conditions, including plant upset. It was decided that Florida would build a combined environmental testing facility to test specific devices in high-radiation/high-temperature combined environments. This environmental test chamber has been built and successfully tested to over 250 degree F. This facility will provide some of the first combined temperatures/radiation data for many large-scale integrated components

  7. Design and characterization of cellulose nanocrystal-enhanced epoxy hardeners

    Science.gov (United States)

    Shane X. Peng; Robert J. Moon; Jeffrey P. Youngblood

    2014-01-01

    Cellulose nanocrystals (CNCs) are renewable, sustainable, and abundant nanomaterial widely used as reinforcing fillers in the field of polymer nanocomposites. In this study, two-part epoxy systems with CNC-enhanced hardeners were fabricated. Three types of hardeners, Jeffamine D400 (JD400), diethylenetriamine (DETA), and (±)-trans-1,2- diaminocyclohexane (DACH), were...

  8. ANISOTROPIC STRAIN-HARDENING IN POLYCRYSTALLINE COPPER AND ALUMINUM

    NARCIS (Netherlands)

    HESS, F

    1993-01-01

    A new viscoplastic model for the plastic stress-strain behaviour of f.c.c. metals is presented. In this model the strain hardening results from increasing dislocation densities. The observed stagnation of strain hardening after strain reversals is explained by a lowering of the increase in

  9. The Reuni Program and Challenges for Professional Education in Social Work

    Directory of Open Access Journals (Sweden)

    Kátia Regina de Souza Lima

    2013-11-01

    Full Text Available This article analyzes the implementation of the Program for Support to Plans for the Restructuring and Expansion of Federal Universities (Reuni, particularly concerning the expansion of the number of openings for students in the schools of Social Work at federal universities. It identifies Reuni as an expression of the expansion policy underway in Brazil in the first decade of the new century. The text analyzes the political and pedagogical significance of the program, it’s impacts on the intensification of the work of teaching and on professional education in Social Work.

  10. In-air and pressurized water reactor environment fatigue experiments of 316 stainless steel to study the effect of environment on cyclic hardening

    Energy Technology Data Exchange (ETDEWEB)

    Mohanty, Subhasish, E-mail: smohanty@anl.gov; Soppet, William K., E-mail: soppet@anl.gov; Majumdar, Saurindranath, E-mail: majumdar@anl.gov; Natesan, Krishnamurti, E-mail: natesan@anl.gov

    2016-05-15

    Argonne National Laboratory (ANL), under the sponsorship of Department of Energy's Light Water Reactor Sustainability (LWRS) program, is trying to develop a mechanistic approach for more accurate life estimation of LWR components. In this context, ANL has conducted many fatigue experiments under different test and environment conditions on type 316 stainless steel (316 SS) material which is widely used in the US reactors. Contrary to the conventional S ∼ N curve based empirical fatigue life estimation approach, the aim of the present DOE sponsored work is to develop an understanding of the material ageing issues more mechanistically (e.g. time dependent hardening and softening) under different test and environmental conditions. Better mechanistic understanding will help develop computer-based advanced modeling tools to better extrapolate stress-strain evolution of reactor components under multi-axial stress states and hence help predict their fatigue life more accurately. Mechanics-based modeling of fatigue such as by using finite element (FE) tools requires the time/cycle dependent material hardening properties. Presently such time-dependent material hardening properties are hardly available in fatigue modeling literature even under in-air conditions. Getting those material properties under PWR environment, are even harder. Through this work we made preliminary attempt to generate time/cycle dependent stress-strain data both under in-air and PWR water conditions for further study such as for possible development of material models and constitutive relations for FE model implementation. Although, there are open-ended possibility to further improve the discussed test methods and related material estimation techniques we anticipate that the data presented in this paper will help the metal fatigue research community particularly, the researchers who are dealing with mechanistic modeling of metal fatigue such as using FE tools. In this paper the fatigue

  11. Planning integration FY 1995 Multi-Year Program Plan (MYPP)/Fiscal Year Work Plan (FYWP)

    International Nuclear Information System (INIS)

    1994-09-01

    This Multi-Year Program Plan (MYPP) for the Planning Integration Program, Work Breakdown structure (WBS) Element 1.8.2, is the primary management tool to document the technical, schedule, and cost baseline for work directed by the US Department of Energy (DOE), Richland Operations Office (RL). As an approved document, it establishes a binding agreement between RL and the performing contractors for the work to be performed. It was prepared by the Westinghouse Hanford Company (WHC) and the Pacific Northwest Laboratory (PNL). This MYPP provides a picture from fiscal year 1995 through FY 2001 for the Planning Integration Program. The MYPP provides a window of detailed information for the first three years. It also provides 'execution year' work plans. The MYPP provides summary information for the next four years, documenting the same period as the Activity Data Sheets

  12. Planning integration FY 1995 Multi-Year Program Plan (MYPP)/Fiscal Year Work Plan (FYWP)

    Energy Technology Data Exchange (ETDEWEB)

    1994-09-01

    This Multi-Year Program Plan (MYPP) for the Planning Integration Program, Work Breakdown structure (WBS) Element 1.8.2, is the primary management tool to document the technical, schedule, and cost baseline for work directed by the US Department of Energy (DOE), Richland Operations Office (RL). As an approved document, it establishes a binding agreement between RL and the performing contractors for the work to be performed. It was prepared by the Westinghouse Hanford Company (WHC) and the Pacific Northwest Laboratory (PNL). This MYPP provides a picture from fiscal year 1995 through FY 2001 for the Planning Integration Program. The MYPP provides a window of detailed information for the first three years. It also provides `execution year` work plans. The MYPP provides summary information for the next four years, documenting the same period as the Activity Data Sheets.

  13. Metabolites and hormones are involved in the intraspecific variability of drought hardening in radiata pine.

    Science.gov (United States)

    De Diego, N; Saiz-Fernández, I; Rodríguez, J L; Pérez-Alfocea, P; Sampedro, M C; Barrio, R J; Lacuesta, M; Moncaleán, P

    2015-09-01

    Studies of metabolic and physiological bases of plant tolerance and hardening against drought are essential to improve genetic breeding programs, especially in productive species such as Pinus radiata. The exposure to different drought cycles is a highly effective tool that improves plant conditioning, but limited information is available about the mechanisms that modulate this process. To clarify this issue, six P. radiata breeds with well-known differences in drought tolerance were analyzed after two consecutive drought cycles. Survival rate, concentration of several metabolites such as free soluble amino acids and polyamines, and main plant hormones varied between them after drought hardening, while relative growth ratio and water potential at both predawn and dawn did not. Hardening induced a strong increase in total soluble amino acids in all breeds, accumulating mainly those implicated in the glutamate metabolism (GM), especially L-proline, in the most tolerant breeds. Other amino acids from GM such as γ-aminobutyric acid (GABA) and L-arginine (Arg) were also strongly increased. GABA pathway could improve the response against drought, whereas Arg acts as precursor for the synthesis of spermidine. This polyamine showed a positive relationship with the survival capacity, probably due to its role as antioxidant under stress conditions. Finally, drought hardening also induced changes in phytohormone content, showing each breed a different profile. Although all of them accumulated indole-3-acetic acid and jasmonic acid and reduced zeatin content in needles, significant differences were observed regarding abscisic acid, salicylic acid and mainly zeatin riboside. These results confirm that hardening is not only species-dependent but also an intraspecific processes controlled through metabolite changes. Copyright © 2015 Elsevier GmbH. All rights reserved.

  14. Saturation behavior of irradiation hardening in F82H irradiated in the HFIR

    Energy Technology Data Exchange (ETDEWEB)

    Hirose, T. [Blanket Engineering Group, Japan Atomic Energy Agency, Naka, Ibaraki (Japan); Shiba, K.; Tanigawa, H.; Ando, M. [Japan Atomic Energy Agency, Tokai-mura, Naga-gun, Ibaraki-ken (Japan); Klueh, R.L. [Oak Ridge National Laboratory, TN (United States); Stoller, R. [ORNL - Oak Ridge National Laboratory, Materials Science and Technology Div., Oak Ridge, AK TN (United States)

    2007-07-01

    Full text of publication follows: Post irradiation tensile tests on reduced activation ferritic/martensitic steel, F82H have been conducted over the past two decades using Japan Materials Testing Reactor (JMTR) of JAEA, and Fast Flux Testing Facility (FFTF) of PNNL and High Flux Isotope Reactor (HFIR) of ORNL, USA, under Japan/US collaboration programs. According to these results, F82H does not demonstrate irradiation hardening above 673 K up to 60 dpa. The current study has been concentrated on hardening behavior at temperature around 573 K. A series of low temperature irradiation experiment has been conducted at the HFIR under the international collaborative research between JAEA/US-DOE. In this collaboration, the irradiation condition is precisely controlled by the well matured capsule designing and instrumentation. This paper summarizes recent results of the irradiation experiments focused on F82H and its modified steels compared with the irradiation properties database on F82H. Post irradiation tensile tests have been conducted on the F82H and its modified steels irradiated at 573 K and the dose level was up to 25 dpa. According to these results, irradiation hardening of F82H is saturated by 9 dpa and the as-irradiated 0.2 % proof stress is less than 1 GPa at ambient temperature. The deterioration of total elongation was also saturated by 9 dpa irradiation. The ductility of some modified steels which showed larger total elongation than that of F82H before irradiation become the same level as that of standard F82H steel after irradiation, even though its magnitude of irradiation hardening is smaller than that of F82H. This suggests that the more ductile steel demonstrates the more ductility loss at this temperature, regardless to the hardening level. The difference in ductility loss behavior between various tensile specimens will be discussed as the ductility could depend on the specimen dimension. (authors)

  15. Coating compositions hardenable by ionization beams

    International Nuclear Information System (INIS)

    Chaudhari, D.; Haering, E.; Dobbelstein, A.; Hoselmann, W.

    1976-01-01

    Coating compositions hardenable by ionizing radiation comprise as binding agents a mixture of A. at least 1 unsaturated olefin compound containing urethane groups, and B. at least 1 further unsaturated olefin compound that may be copolymerized. The unsaturated olefin compound A. containing the urethane groups in a reaction product of (a) a compound of the general formula (CHR 1 = CR 2 COOCH 2 CH(OH)CH 2 O CO-)/sub n/R where n is 1 or 2, where R stands for a straight chain or branched alkyl group of valence n, where R 1 is hydrogen, methyl; or the group -COOCH 2 CH(OH)CH 2 OCOR 3 - where R 3 is a monovalent alkyl residue and where R 2 is hydrogen or methyl, and (b) a compound containing at least 1 isocyanate group where the mixture of (A) and (B) may contain conventional additives of the lacquer industry. 6 claims

  16. Keystroke Dynamics-Based Credential Hardening Systems

    Science.gov (United States)

    Bartlow, Nick; Cukic, Bojan

    abstract Keystroke dynamics are becoming a well-known method for strengthening username- and password-based credential sets. The familiarity and ease of use of these traditional authentication schemes combined with the increased trustworthiness associated with biometrics makes them prime candidates for application in many web-based scenarios. Our keystroke dynamics system uses Breiman’s random forests algorithm to classify keystroke input sequences as genuine or imposter. The system is capable of operating at various points on a traditional ROC curve depending on application-specific security needs. As a username/password authentication scheme, our approach decreases the system penetration rate associated with compromised passwords up to 99.15%. Beyond presenting results demonstrating the credential hardening effect of our scheme, we look into the notion that a user’s familiarity to components of a credential set can non-trivially impact error rates.

  17. Radiation hardening of MOS devices by boron

    International Nuclear Information System (INIS)

    Danchenko, V.

    1975-01-01

    A novel technique is disclosed for radiation hardening of MOS devices and specifically for stabilizing the gate threshold potential at room temperature of a radiation subjected MOS field-effect device of the type having a semiconductor substrate, an insulating layer of oxide on the substrate, and a gate electrode disposed on the insulating layer. In the preferred embodiment, the novel inventive technique contemplates the introduction of boron into the insulating oxide, the boron being introduced within a layer of the oxide of about 100A to 300A thickness immediately adjacent the semiconductor-insulator interface. The concentration of boron in the oxide layer is preferably maintained on the order of 10 atoms/ cm 3 . The novel technique serves to reduce and substantially annihilate radiation induced positive gate charge accumulations, which accumulations, if not eliminated, would cause shifting of the gate threshold potential of a radiation subjected MOS device, and thus render the device unstable and/or inoperative. (auth)

  18. Rapid cold hardening: a gut feeling.

    Science.gov (United States)

    Worland, M R; Convey, P; Luke ov , A

    2000-01-01

    This study examined the rate of cold hardening of a field population of Antarctic springtails and the effect of eating food with particular levels of ice nucleating activity on the animal's whole body freezing point. The SCPs of samples of c. 20, freshly collected, Cryptopygus antarcticus were measured hourly over a 32 hour collection period using differential scanning calorimetry and related to habitat temperature. The mean SCP of the springtails increased from -24 to -10 degree C during which time the habitat temperature warmed slowly from -2.5 to +2.5 degree C. In laboratory experiments, previously starved, cold tolerant springtails were fed on selected species of algae with measured SCP's but there was no clear correlation between the SCP of food and that of the animals after feeding. Microscopic examination of faecal pellets and guts from springtails showed that algal cells were completely destroyed during digestion.

  19. The Mount Sinai international enhancement of social work leadership program: The past and the future.

    Science.gov (United States)

    Gordon, Elisa; Green, Karen; Whitwam, Louisa; Epstein, Irwin; Bernstein, Susan

    2018-07-01

    Developed in 1988, the Mount Sinai International Enhancement of Social Work Leadership Program brings 4-6 social workers from several countries each year to the Mount Sinai Hospital in New York City, where they meet with leaders from the hospital, community based organizations and graduate schools of social work, to enhance their leadership ability, strengthen management and research skills, and build upon global social work relationships. This article reviews the results of a survey conducted in 2016 to assess whether the visiting scholars met established learning objectives of the Program. Survey outcomes, presented in quantitative and qualitative terms, show positive results, and the scholars reported that the Program was extremely beneficial. The Program is viewed through the lens of two select adult learning theories: Social Learning Theory, which incorporates collaboration and learning from others, and Transformative Learning Theory, which is comprised of self-reflection and individualized learning. The inclusion of these theories in the implementation of the Program will be discussed. An analysis of the survey's outcomes, through pre- and post-Program participation and learning, facilitates assessment of potential programmatic adjustments to help evaluate long-term viability of the Program and potential duplication by other academic medical centers.

  20. 78 FR 35642 - Certain TV Programs, Literary Works for TV Production and Episode Guides Pertaining to Same...

    Science.gov (United States)

    2013-06-13

    ... INTERNATIONAL TRADE COMMISSION [Docket No 2959] Certain TV Programs, Literary Works for TV... Certain TV Programs, Literary Works for TV Production and Episode Guides Pertaining to Same, DN 2959; the... importation of certain TV programs, literary works for TV production and episode guides pertaining to same...

  1. Radiation hardening of optical fibers and fiber sensors for space applications: recent advances

    Science.gov (United States)

    Girard, S.; Ouerdane, Y.; Pinsard, E.; Laurent, A.; Ladaci, A.; Robin, T.; Cadier, B.; Mescia, L.; Boukenter, A.

    2017-11-01

    In these ICSO proceedings, we review recent advances from our group concerning the radiation hardening of optical fiber and fiber-based sensors for space applications and compare their benefits to state-of-the-art results. We focus on the various approaches we developed to enhance the radiation tolerance of two classes of optical fibers doped with rare-earths: the erbium (Er)-doped ones and the ytterbium/erbium (Er/Yb)-doped ones. As a first approach, we work at the component level, optimizing the fiber structure and composition to reduce their intrinsically high radiation sensitivities. For the Erbium-doped fibers, this has been achieved using a new structure for the fiber that is called Hole-Assisted Carbon Coated (HACC) optical fibers whereas for the Er/Ybdoped optical fibers, their hardening was successfully achieved adding to the fiber, the Cerium element, that prevents the formation of the radiation-induced point defects responsible for the radiation induced attenuation in the infrared part of the spectrum. These fibers are used as part of more complex systems like amplifiers (Erbium-doped Fiber Amplifier, EDFA or Yb-EDFA) or source (Erbium-doped Fiber Source, EDFS or Yb- EDFS), we discuss the impact of using radiation-hardened fibers on the system radiation vulnerability and demonstrate the resistance of these systems to radiation constraints associated with today and future space missions. Finally, we will discuss another radiation hardening approach build in our group and based on a hardening-by-system strategy in which the amplifier is optimized during its elaboration for its future mission considering the radiation effects and not in-lab.

  2. Hardening of ODS ferritic steels under irradiation with high-energy heavy ions

    Science.gov (United States)

    Ding, Z. N.; Zhang, C. H.; Yang, Y. T.; Song, Y.; Kimura, A.; Jang, J.

    2017-09-01

    Influence of the nanoscale oxide particles on mechanical properties and irradiation resistance of oxide-dispersion-strengthened (ODS) ferritic steels is of critical importance for the use of the material in fuel cladding or blanket components in advanced nuclear reactors. In the present work, impact of structures of oxide dispersoids on the irradiation hardening of ODS ferritic steels was studied. Specimens of three high-Cr ODS ferritic steels containing oxide dispersoids with different number density and average size were irradiated with high-energy Ni ions at about -50 °C. The energy of the incident Ni ions was varied from 12.73 MeV to 357.86 MeV by using an energy degrader at the terminal so that a plateau of atomic displacement damage (∼0.8 dpa) was produced from the near surface to a depth of 24 μm in the specimens. A nanoindentor (in constant stiffness mode with a diamond Berkovich indenter) and a Vickers micro-hardness tester were used to measure the hardeness of the specimens. The Nix-Gao model taking account of the indentation size effect (ISE) was used to fit the hardness data. It is observed that the soft substrate effect (SSE) can be diminished substantially in the irradiated specimens due to the thick damaged regions produced by the Ni ions. A linear correlation between the nano-hardeness and the micro-hardness was found. It is observed that a higher number density of oxide dispersoids with a smaller average diameter corresponds to an increased resistance to irradiation hardening, which can be ascribed to the increased sink strength of oxides/matrix interfaces to point defects. The rate equation approach and the conventional hardening model were used to analyze the influence of defect clusters on irradiation hardening in ODS ferritic steels. The numerical estimates show that the hardening caused by the interstitial type dislocation loops follows a similar trend with the experiment data.

  3. Virtual reality based support system for layout planning and programming of an industrial robotic work cell.

    Science.gov (United States)

    Yap, Hwa Jen; Taha, Zahari; Dawal, Siti Zawiah Md; Chang, Siow-Wee

    2014-01-01

    Traditional robotic work cell design and programming are considered inefficient and outdated in current industrial and market demands. In this research, virtual reality (VR) technology is used to improve human-robot interface, whereby complicated commands or programming knowledge is not required. The proposed solution, known as VR-based Programming of a Robotic Work Cell (VR-Rocell), consists of two sub-programmes, which are VR-Robotic Work Cell Layout (VR-RoWL) and VR-based Robot Teaching System (VR-RoT). VR-RoWL is developed to assign the layout design for an industrial robotic work cell, whereby VR-RoT is developed to overcome safety issues and lack of trained personnel in robot programming. Simple and user-friendly interfaces are designed for inexperienced users to generate robot commands without damaging the robot or interrupting the production line. The user is able to attempt numerous times to attain an optimum solution. A case study is conducted in the Robotics Laboratory to assemble an electronics casing and it is found that the output models are compatible with commercial software without loss of information. Furthermore, the generated KUKA commands are workable when loaded into a commercial simulator. The operation of the actual robotic work cell shows that the errors may be due to the dynamics of the KUKA robot rather than the accuracy of the generated programme. Therefore, it is concluded that the virtual reality based solution approach can be implemented in an industrial robotic work cell.

  4. Navigating Return to Work and Breastfeeding in a Hospital with a Comprehensive Employee Lactation Program.

    Science.gov (United States)

    Froh, Elizabeth B; Spatz, Diane L

    2016-11-01

    The Surgeon General's Call to Action to Support Breastfeeding details the need for comprehensive employer lactation support programs. Our institution has an extensive employee lactation program, and our breastfeeding initiation and continuation rates are statistically significantly higher than state and national data, with more than 20% of our employees breastfeeding for more than 1 year. The objective of this research was complete secondary data analysis of qualitative data collected as part of a larger study on breastfeeding outcomes. In the larger study, 545 women who returned to work full or part time completed an online survey with the ability to provide free text qualitative data and feedback regarding their experiences with breastfeeding after return to work. Qualitative data were pulled from the online survey platform. The responses to these questions were analyzed using conventional content analysis by the research team (2 PhD-prepared nurse researchers trained and experienced in qualitative methodologies and 1 research assistant) in order to complete a thematic analysis of the survey data. Analysis of the data yielded 5 major themes: (1) positive reflections, (2) nonsupportive environment/work culture, (3) supportive environment/work culture, (4) accessibility of resources, and (5) internal barriers. The themes that emerged from this research clearly indicate that even in a hospital with an extensive employee lactation program, women have varied experiences-some more positive than others. Returning to work while breastfeeding requires time and commitment of the mother, and a supportive employee lactation program may ease that transition of return to work.

  5. The Development of International Programs in a School of Social Work

    Directory of Open Access Journals (Sweden)

    Frank B. Raymond

    2014-04-01

    Full Text Available During the last decade increasing numbers of schools of social work have adopted an international mission and have developed a variety of activities to reflect their global perspective. In earlier years, however, relatively few schools expressed a global mission, offered coursework on international social work, provided field placements or other opportunities to expose students to international learning, or extended components of their academic programs to other countries. An early leader in doing such things was the College of Social Work at the University of South Carolina (COSW, where the author was privileged to serve as dean for 22 years (1980-2002 when many of these developments occurred. This paper will discuss how this school acquired an international mission and developed various programs to manifest this commitment. The paper will describe, in particular, the college’s signature achievement in international social work education – the development and implementation of a Korea-based MSW program. The COSW was the first school of social work in the US to offer a master’s degree in its entirety in a foreign country. It is hoped that the recounting of this school’s experiences will offer guidance to other social work education programs that are exploring ways of expanding their international initiatives.

  6. Hardening Effect Analysis by Modular Upper Bound and Finite Element Methods in Indentation of Aluminum, Steel, Titanium and Superalloys

    Directory of Open Access Journals (Sweden)

    Carolina Bermudo

    2017-05-01

    Full Text Available The application of incremental processes in the manufacturing industry is having a great development in recent years. The first stage of an Incremental Forming Process can be defined as an indentation. Because of this, the indentation process is starting to be widely studied, not only as a hardening test but also as a forming process. Thus, in this work, an analysis of the indentation process under the new Modular Upper Bound perspective has been performed. The modular implementation has several advantages, including the possibility of the introduction of different parameters to extend the study, such as the friction effect, the temperature or the hardening effect studied in this paper. The main objective of the present work is to analyze the three hardening models developed depending on the material characteristics. In order to support the validation of the hardening models, finite element analyses of diverse materials under an indentation are carried out. Results obtained from the Modular Upper Bound are in concordance with the results obtained from the numerical analyses. In addition, the numerical and analytical methods are in concordance with the results previously obtained in the experimental indentation of annealed aluminum A92030. Due to the introduction of the hardening factor, the new modular distribution is a suitable option for the analysis of indentation process.

  7. Work-life balance of nursing faculty in research- and practice-focused doctoral programs.

    Science.gov (United States)

    Smeltzer, Suzanne C; Sharts-Hopko, Nancy C; Cantrell, Mary Ann; Heverly, Mary Ann; Jenkinson, Amanda; Nthenge, Serah

    2015-01-01

    The growing shortage of nursing faculty and the need for faculty to teach doctoral students to address the shortage call for examination of factors that may contribute to the shortage, including those that are potentially modifiable, including work-life balance.This descriptive study examined work-life balance of a national sample of nursing faculty teaching in research-focused and practice-focused doctoral programs. Data were collected through an online survey of 554 doctoral program faculty members to identify their perceptions of work-life balance and predictors of work-life balance. Work-life balance scores indicated better work-life balance than expected. Factors associated with good work-life balance included higher academic rank, having tenure, older age, years in education, current faculty position, and no involvement in clinical practice. Current faculty position was the best predictor of work-life balance. Although work-life balance was viewed positively by study participants, efforts are needed to strengthen factors related to positive work/life in view of the increasing workload of doctoral faculty as the numbers of doctoral students increase and the number of seasoned faculty decrease with anticipated waves of retirements. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. Work-Related Asthma in Korea - Findings from the Korea Work-Related Asthma Surveillance (KOWAS) program, 2004-2009.

    Science.gov (United States)

    Kwon, Soon-Chan; Song, Jaechul; Kim, Yong-Kyu; Calvert, Geoffrey M

    2015-01-01

    To determine the incidence and epidemiological characteristics of work-related asthma in Korea. During 2004-2009, the Korea Work-Related Asthma Surveillance (KOWAS) program collected data on new cases of work-related asthma from occupational physicians, allergy and chest physicians, regional surveillance systems, and workers' compensation schemes. The incidence was calculated on the basis of industry, occupation, sex, age, and region. In addition, the distribution of causal agents was determined. During the study period, 236 cases of work-related asthma were reported, with 77 cases from more than 1 source. A total of 22.0% (n=52) were reported by occupational physicians, 52.5% (n=124) by allergy and chest physicians, 24.2% (n=57) by regional surveillance systems, and 43.2% (n=102) by workers' compensation schemes. The overall average annual incidence was 3.31 cases/million workers, with a rate of 3.78/million among men and 2.58/million among women. The highest incidence was observed in the 50-59-year age group (7.74/million), in the Gyeonggi/Incheon suburb of Seoul (8.50/million), in the furniture and other instrument manufacturing industries (67.62/million), and among craft and related trades workers (17.75/million). The most common causal agents were isocyanates (46.6%), flour/grain (8.5%), metal (5.9%), reactive dyes (5.1%), and solvents (4.2%). The incidence of work-related asthma in Korea was relatively low, and varied according to industry, occupation, gender, age, and region. Data provided by workers' compensation schemes and physician reports have been useful for determining the incidence and causes of work-related asthma.

  9. Preparation of Self Hardening-modelling Polyurethane for Wood Repairing and Cracks Injection

    International Nuclear Information System (INIS)

    Meligi, G.A.; Elnahas, H.H.; Ammar, A.H.

    2014-01-01

    Self hardening composite as a modelling clay was prepared from polyurethane, two parts (A) and (B) where (A) contains polyol (polyether), vinyl acetate versatic ester copolymer (VAcVe) and magnesium silicate or wood powder and (B) contains toluene diisocyanate (TDI) as a hardening agent. The two parts mixed thoroughly giving soft putty like feel, open working time 1-2 h and cures hard overnight (24 h full cure). Factors affecting working time and full cure were evaluated. Also, measurements of surface hardness, compressive strength, scanning electron microscopy (SEM), water absorption and effect of ionizing radiation were studied. The suggestion for using the prepared polyurethane composite as clay dries as hard as a rock in the field of wood repair and cracks injection for building walls were recommended. Keywords: Polyurethane, modelling clay, radiation, wood repair and cracks injection.

  10. The Hanford Site Environmental Restoration Program 1993 fiscal year work plan

    International Nuclear Information System (INIS)

    1992-09-01

    Site Management System (SMS) guidance requires a Fiscal Year Work Plan (FYWP) be prepared for the Environmental Restoration (ER) Mission Area and all related programs. This document describes the overall ER Mission Area and provides FYWP appendixes for each of the five program areas: Remedial Action (RA); Decontamination and Decommissioning (D ampersand D); Project Management and Support (PM ampersand S); Surveillance and Maintenance (S ampersand M); and Treatment, Storage, and/or Disposal (TSD)

  11. Impact of a health promotion program on employee health risks and work productivity.

    Science.gov (United States)

    Mills, Peter R; Kessler, Ronald C; Cooper, John; Sullivan, Sean

    2007-01-01

    Evaluate the impact of a multicomponent workplace health promotion program on employee health risks and work productivity. Quasi-experimental 12-month before-after intervention-control study. A multinational corporation headquartered in the United Kingdom. Of 618 employees offered the program, 266 (43%) completed questionnaires before and after the program. A total of 1242 of 2500 (49.7%) of a control population also completed questionnaires 12 months apart. A multicomponent health promotion program incorporating a health risk appraisal questionnaire, access to a tailored health improvement web portal, wellness literature, and seminars and workshops focused upon identified wellness issues. Outcomes were (1) cumulative count of health risk factors and the World Health Organization health and work performance questionnaire measures of (2) workplace absenteeism and (3) work performance. After adjusting for baseline differences, improvements in all three outcomes were significantly greater in the intervention group compared with the control group. Mean excess reductions of 0.45 health risk factors and 0.36 monthly absenteeism days and a mean increase of 0.79 on the work performance scale were observed in the intervention group compared with the control group. The intervention yielded a positive return on investment, even using conservative assumptions about effect size estimation. The results suggest that a well-implemented multicomponent workplace health promotion program can produce sizeable changes in health risks and productivity.

  12. A Process and Outcome Evaluation of Police Working with Youth Programs

    Directory of Open Access Journals (Sweden)

    Stephen A. Anderson

    2008-09-01

    Full Text Available A process and outcome evaluation of 10 Police Working with Youth Programs was conducted. Process results indicated that the core components of the programs were consistent with those identified in previous literature as characteristic of quality youth development programs. Outcome results indicated that youth participants reported significantly improved attitudes toward police and social support received from significant, non-familial adults. Two subgroups of youth, most notably minority youth and younger participants in lower grade levels, reported positive changes in their capacity to resist peer pressures. Minority youth reported positive changes in their sense of mastery over stressful life situations. Relationships between core program components and youth outcomes also were examined. Implications of the findings and future process and outcome evaluations of youth programs are discussed.

  13. Favourable environmental factors for shaft furnace installation for gas carbonitriding and hardening

    Energy Technology Data Exchange (ETDEWEB)

    Fuchs, H. (Solo-Industrieofenbau, Biehl-Bienne (Switzerland))

    In this lecture we do not primarily speak about the shaft furnace installation as one could think when reading the title - but about one quenching system - mounted over the shaft furnace installation. This quenching system permits a hardening in several mediums, without any formation of flames, smoke and vapour, and causes the surfaces of the pieces to be free of tinder. Moreover, the security for the work staff in the heat treatment shops are highly improved.

  14. Requirements for an ES and H assurance program at the working levels of organization

    International Nuclear Information System (INIS)

    Tierney, M.S.; Ellingson, A.C.

    1979-07-01

    Means by which the disciplines of quality assurance (QA), reliability (R), and human factors (HF) might be used to the advantage of Environment, Safety, and Health (ES and H) programs are being investigated. A generalized model assurance program, based on QA, R, and HF principles but specifically tailored to ES and H program needs, has been developed. Current studies address implementation of the model assurance program at the working levels of organization. It appears that the only way practicability at the working level can be determined is by the case study method. The present study represents a first step in the application of such a procedure. An attempt was made to approach the question of practicability by first constructing a generic ES and H assurance plan for working-level organizations that is based upon the more widely-applied model plan and studies mentioned earlier. Then the elements of this generic working-level plan were compared with the practices of an existing R and D organization at Sandia Laboratories, Albuquerque. Some of the necessary steps were taken to convert these practices to those required by the generic plan in order to gain a measure of the feasibility, cost, and some of the possible benefits of such a conversion. Partial results of one case study are presented, and some generalizations that emerge regarding the structure of an idealized working-level ES and H plan are made

  15. Mapping Dual-Degree Programs in Social Work and Public Health: Results From a National Survey

    Directory of Open Access Journals (Sweden)

    Dory Ziperstein

    2016-02-01

    Full Text Available Dramatic changes in the health system due to national health reform are raising important questions regarding the educational preparation of social workers for the new health arena. While dual-degree programs in public health and social work can be an important response to what is needed educationally, little is known about them. The National MSW/MPH Programs Study surveyed MSW/MPH program administrators to better understand the prevalence, models, structure, and challenges of these dual-degree programs. Forty-two programs were identified, and 97.6% of those contacted participated (n=41. Findings indicate that MSW/MPH programs are popular, increasing, geographically dispersed, and drawing talented students interested in trans-disciplinary public health social work practice. Challenges for these programs include the need for greater institutional support, particularly funding, and a general lack of best practices for MSW/MPH education. While findings from this study suggest graduates appear especially well-prepared for leadership and practice in the new health environment, additional research is needed to assess their particular contributions and career trajectories.

  16. Development and Implementation of a Mental Health Work Rehabilitation Program: Results of a Developmental Evaluation.

    Science.gov (United States)

    Sylvain, Chantal; Durand, Marie-José; Velasquez Sanchez, Astrid; Lessard, Nathalie; Maillette, Pascale

    2018-05-23

    Purpose Long-term work disability due to common mental disorders (CMDs) is a growing problem. Yet optimal interventions remain unclear and little is known about implementation challenges in everyday practice. This study aimed to support and evaluate, in real time, the development and implementation of a work rehabilitation program (WRP) designed to promote post-CMD return-to-work (RTW). Methods A 2-year developmental evaluation was performed using a participatory approach. At program outset, the researchers held five work meetings to revise the program's logic model and discuss its underlying change theory with clinicians. Data collection tools used throughout the study period were structured charts of activities conducted with workers (n = 41); in-depth interviews with program clinicians and managers (n = 9); and participant observation during work meetings. Quantitative data were analyzed using descriptive statistics. Qualitative data underwent thematic analysis using a processual approach. Results Three types of activity were developed and implemented: individual and group interventions targeting workers, and joint activities targeting partners (physicians, employers, others). While worker-targeted activities were generally implemented as planned, joint activities were sporadic. Analysis of the implementation process revealed five challenges faced by clinicians. Determinants included clinicians, host organization, sociopolitical context and resources provided by the evaluation. Conclusion The program studied is original in that it is based on the best available scientific knowledge, yet adapted to contextual particularities. The identified implementation challenges highlight the need for greater importance to be placed on the external, non-program context to ensure sustainable implementation in everyday practice.

  17. The influence of the hardening coolant agent on the properties of hot rolled bars of the steel 42CrMo4

    Directory of Open Access Journals (Sweden)

    M. Stańczyk

    2014-10-01

    Full Text Available In the work the influence results of two different hardening coolant agents on the basic mechanical proprieties and microstructure of the round hot rolled bars were presented. The bars of 42CrMo4 steel were exposed to analysis, and for those bars in the hardening process, water and modern pro-ecological polymer cooling agents Aqua Quench MK were used.

  18. Open Source Radiation Hardened by Design Technology

    Science.gov (United States)

    Shuler, Robert

    2016-01-01

    The proposed technology allows use of the latest microcircuit technology with lowest power and fastest speed, with minimal delay and engineering costs, through new Radiation Hardened by Design (RHBD) techniques that do not require extensive process characterization, technique evaluation and re-design at each Moore's Law generation. The separation of critical node groups is explicitly parameterized so it can be increased as microcircuit technologies shrink. The technology will be open access to radiation tolerant circuit vendors. INNOVATION: This technology would enhance computation intensive applications such as autonomy, robotics, advanced sensor and tracking processes, as well as low power applications such as wireless sensor networks. OUTCOME / RESULTS: 1) Simulation analysis indicates feasibility. 2)Compact voting latch 65 nanometer test chip designed and submitted for fabrication -7/2016. INFUSION FOR SPACE / EARTH: This technology may be used in any digital integrated circuit in which a high level of resistance to Single Event Upsets is desired, and has the greatest benefit outside low earth orbit where cosmic rays are numerous.

  19. Radiation hardening of CMOS-based circuitry in SMART transmitters

    International Nuclear Information System (INIS)

    Loescher, D.H.

    1993-02-01

    Process control transmitters that incorporate digital signal processing could be used advantageously in nuclear power plants; however, because such transmitters are too sensitive to radiation, they are not used. The Electric Power Research Institute sponsored work at Sandia National Laboratories under EPRI contract RP2614-58 to determine why SMART transmitters fail when exposed to radiation and to design and demonstrate SMART transmitter circuits that could tolerate radiation. The term ''SMART'' denotes transmitters that contain digital logic. Tests showed that transmitter failure was caused by failure of the complementary metal oxide semiconductors (CMOS)-integrated circuits which are used extensively in commercial transmitters. Radiation-hardened replacements were not available for the radiation-sensitive CMOS circuits. A conceptual design showed that a radiation-tolerant transmitter could be constructed. A prototype for an analog-to-digital converter subsection worked satisfactorily after a total dose of 30 megarads(Si). Encouraging results were obtained from preliminary bench-top tests on a dc-to-dc converter for the power supply subsection

  20. Effectiveness of physical activity programs at worksites with respect to work-related outcomes

    NARCIS (Netherlands)

    Proper, K.I.; Staal, B.J.; Hildebrandt, V.H.; Beek, A.J. van der; Mechelen, W. van

    2002-01-01

    This paper systematically reviews the literature on the effectiveness of physical activity programs at worksites with respect to work-related outcomes. A computerized literature search, a reference search, and a manual search of personal databases were performed using the following inclusion

  1. Work-Integrated Learning Process in Tourism Training Programs in Vietnam: Voices of Education and Industry

    Science.gov (United States)

    Khuong, Cam Thi Hong

    2016-01-01

    This paper addresses the work-integrated learning (WIL) initiative embedded in selected tourism training programs in Vietnam. The research was grounded on the framework of stakeholder ethos. Drawing on tourism training curriculum analysis and interviews with lecturers, institutional leaders, industry managers and internship supervisors, this study…

  2. Quality of Work-Life Programs in U.S. Medical Schools: Review and Case Studies

    Science.gov (United States)

    Otto, Ann; Bourguet, Claire

    2006-01-01

    Quality of work life is being recognized more and more as a driving factor in the recruitment and retention of highly qualified employees. Before Northeastern Ohio Universities College of Medicine began development of its QWL initiative, it surveyed other medical schools across the U.S. to determine benchmarks of best practices in these programs.…

  3. Effectiveness of a Multilevel Workplace Health Promotion Program on Vitality, Health, and Work-Related Outcomes

    NARCIS (Netherlands)

    Hendriksen, I.J.M.; Snoijer, M.; Kok, B.P. de; Vlisteren, J. van; Hofstetter, H.

    2016-01-01

    Objective: Evaluation of the effectiveness of a workplace health promotion program on employees’ vitality, health, and work-related outcomes, and exploring the influence of organizational support and the supervisors’ role on these outcomes. Methods: The 5-month intervention included activities at

  4. Effects of a Cooperative Learning Program on the Elaborations of Students Working in Dyads

    NARCIS (Netherlands)

    Krol, K.; Janssen, J.J.H.M.; Veenman, S.A.M.; Linden, A.A.M. van der

    2004-01-01

    In this study, the effects of a school improvement program on cooperative learning (CL) with respect to the elaborations of 6th-grade students working in mixed-ability and mixed-sex dyads on 2 cooperative tasks were examined. A posttest-only design with a control group was used to investigate the

  5. Affirmative Action. Module Number 16. Work Experience Program Modules. Coordination Techniques Series.

    Science.gov (United States)

    Shawhan, Carl; Morley, Ray

    This self-instructional module, the last in a series of 16 on techniques for coordinating work experience programs, deals with affirmative action. Addressed in the module are the following topics: the nature of affirmative action legislation and regulations, the role of the teacher-coordinator as a resource person for affirmative action…

  6. Advancement Programs for Disattached Youth: Do They Work? Publication No. 113.

    Science.gov (United States)

    Gottlieb, Avi

    This study of the effects of the Israeli rehabilitation system on disattached youth found little evidence that the programs examined had any impact. Israeli adolescents who neither work nor study are considered to be disattached. These youth are eventually absorbed into a variety of both voluntary and involuntary community residential educational…

  7. Empirically Supported Psychotherapy in Social Work Training Programs: Does the Definition of Evidence Matter?

    Science.gov (United States)

    Bledsoe, Sarah E.; Weissman, Myrna M.; Mullen, Edward J.; Ponniah, Kathryn; Gameroff, Marc J.; Verdeli, Helen; Mufson, Laura; Fitterling, Heidi; Wickramaratne, Priya

    2007-01-01

    Objectives: A national survey finds that 62% of social work programs do not require didactic and clinical supervision in any empirically supported psychotherapy (EST). The authors report the results of analysis of national survey data using two alternative classifications of EST to determine if the results are because of the definition of EST used…

  8. 78 FR 45452 - Mailing of Tickets Under the Ticket To Work Program

    Science.gov (United States)

    2013-07-29

    ... Security Online, at www.socialsecurity.gov . SUPPLEMENTARY INFORMATION: Congress established the Ticket... SOCIAL SECURITY ADMINISTRATION 20 CFR Part 411 [Docket No. SSA-2011-0034] RIN 0960-AH34 Mailing of Tickets Under the Ticket To Work Program AGENCY: Social Security Administration. ACTION: Final rule...

  9. Programs Needed for 2017 Take Your Child to Work Day | Poster

    Science.gov (United States)

    On Wednesday, June 28, the NCI grounds will be filled with the chatter and laughter of children for the 21st annual Take Your Child to Work Day event. Every year, the event aims to spark children’s interest in science through a variety of programs and activities.

  10. Water Conservation and Reuse. Instructor Guide. Working for Clean Water: An Information Program for Advisory Committees.

    Science.gov (United States)

    Pennsylvania State Univ., Middletown. Inst. of State and Regional Affairs.

    Described is a learning session on water conservation intended for citizen advisory groups interested in water quality planning. Topics addressed in this instructor's manual include water conservation needs, benefits, programs, technology, and problems. These materials are components of the Working for Clean Water Project. (Author/WB)

  11. 20 CFR 411.245 - What are a PM's responsibilities under the Ticket to Work program?

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false What are a PM's responsibilities under the Ticket to Work program? 411.245 Section 411.245 Employees' Benefits SOCIAL SECURITY ADMINISTRATION THE... formats. For purposes of this section, accessible format means by media that is appropriate to a...

  12. 76 FR 55946 - Comment Request for Information Collection for the Work Opportunity Tax Credit (WOTC) Program...

    Science.gov (United States)

    2011-09-09

    ... Opportunity Tax Credit (WOTC) Program: Extension With Non-Substantive Revisions AGENCY: Employment and..., ``Certification Workload and Characteristics of Certified Individuals, Work Opportunity Tax Credit'' and provided... submit this report using the Internet-based Tax Credit Reporting System of the Enterprise Business...

  13. All in One Stop? The Accessibility of Work Support Programs at One-Stop Centers.

    Science.gov (United States)

    Richer, Elise; Kubo, Hitomi; Frank, Abbey

    The accessibility of work support programs at one-stop centers was examined in a study during which 33 telephone directors or managers of one-stop centers in 22 states were interviewed by telephone. The interviews established the existence of extensive differences between one-stop centers from the standpoint of all aspects of their operation,…

  14. Hanford environmental management program multi-year work plan FY1998

    International Nuclear Information System (INIS)

    Giese, K.A.

    1997-01-01

    The Environmental Support FY 1998 Multi-Year Work Plan (MYWP), consisting of the Hanford Environmental Management Program (HEMP) and the Effluent and Environmental Monitoring (EEM) Program MYWP is prepared to specifically establish the execution year's work scope, budget targets, and schedule baselines. The work plan contains the work breakdown structure (WBS) and the WBS dictionary, milestone listings and milestone description sheets, and cost targets that the program manager will use to manage program work for the fiscal year. Where activities required to maintain or attain compliance with environmental requirements and agreements are impacted as a result of a reduction of the authorized funds, the ''Work Authorization'' identifies the impacted scope and requires the Contracting Officer's or Assistant Manager-Contracting Officer's Representative signature. Change requests will be submitted to RL by the contractor for approval, further documenting the impacts of any environmental and agreement noncompliances as a result of funding limitations. This is the first year that the MYWPs are submitted under the new Project Hanford Management Contractor (PHMC). The MYWPs are structured differently than in prior years. The MYWP is divided into two main sections. Section One is titled the ''Project Summary Section'' and Section Two is titled the ''Additional Sections at the Project Baseline Summaries Level''. Section One is where the major project summary-level information is provided. Section Two is designed to detail the information for each Project Baseline Summary (PBS) that falls under the purview of the major project listed in Section One. Considering all of the PHMC MYWPs, the HEMP and EEM programs are the one exception to the above description. HEMP and EEM are two of five separate programs that are organized under one common PBS that is titled Mission Support (PBS number-sign RL-OT01). RL has given guidance that HEMP and EEM will be submitted as one common MYWP

  15. Enhancement of the Work in Scia Engineer's Environment by Employment of XML Programming Language

    Directory of Open Access Journals (Sweden)

    Kortiš Ján

    2015-12-01

    Full Text Available The productivity of the work of engineers in the design of building structures by applying the rules of technical standards [1] has been increasing by using different software products for recent years. The software products offer engineers new possibilities to design different structures. However, there are problems especially for design of structures with similar static schemes as it is needed to follow the same work-steps. This can be more effective if the steps are done automatically by using a programming language for leading the processes that are done by software. The design process of timber structure which is done in the environment of Scia Engineer software is presented in the article. XML Programming Language is used for automatization of the design and the XML code is modified in the Excel environment by using VBA Programming language [2], [3].

  16. A Radiation Hardened Housekeeping Slave Node (RH-HKSN) ASIC

    Data.gov (United States)

    National Aeronautics and Space Administration — This projects seeks to continue the development of the Radiation Hardened Housekeeping Slave Node (RH-HKSN) ASIC. The effort has taken parallel paths by implementing...

  17. Radiation-chemical hardening of phenol-formaldehyde oligomers

    International Nuclear Information System (INIS)

    Shlapatskaya, V.V.; Omel'chenko, S.I.

    1978-01-01

    Radiation-chemical hardening of phenol formaldehyde oligomers of the resol type has been studied in the presence of furfural and diallylphthalate diluents. The samples have been hardened on an electron accelerator at an electron energy of 1.0-1.1 MeV and a dose rate of 2-3 Mrad/s. The kinetics of hardening has been studied on the yield of gel fraction within the range of absorbed doses from 7 to 400 Mrad. Radiation-chemical hardening of the studied compositions is activated with sensitizers, namely, amines, metal chlorides, and heterocyclic derivatives of metals. Furfural and diallylphthalate compositions are suitable for forming glass-fibre plastic items by the wet method and coatings under the action of ionizing radiations

  18. Technologies Enabling Custom Radiation-Hardened Component Development, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Two primary paths are available for the creation of a Rad-Hard ASIC. The first approach is to use a radiation hardened process such as existing Rad-Hard foundries....

  19. system hardening architecture for safer access to critical business

    African Journals Online (AJOL)

    eobe

    System hardening is a defence strategy, where several different security measures are applied at various layers, all of which .... commerce have tremendously imparted on corporate services ..... Technology and Exploring Engineering, Vol. 2,.

  20. Space Qualified, Radiation Hardened, Dense Monolithic Flash Memory, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Radiation hardened nonvolatile memories for space is still primarily confined to EEPROM. There is high density effective or cost effective NVM solution available to...

  1. Radiation Hardened Ethernet PHY and Switch Fabric, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Innoflight will develop a new family of radiation hardened (up to 3 Mrad(Si)), fault-tolerant, high data-rate (up to 8 Gbps), low power Gigabit Ethernet PHY and...

  2. Space Qualified, Radiation Hardened, Dense Monolithic Flash Memory, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Space Micro proposes to build a radiation hardened by design (RHBD) flash memory, using a modified version of our RH-eDRAM Memory Controller to solve all the single...

  3. System Hardening Architecture for Safer Access to Critical Business ...

    African Journals Online (AJOL)

    System Hardening Architecture for Safer Access to Critical Business Data. ... and the threat is growing faster than the potential victims can deal with. ... in this architecture are applied to the host, application, operating system, user, and the ...

  4. The Natural Aging Effect on Hardenability in Al-Mg-Si: A Complex Interaction between Composition and Heat Treatment Parameters

    Directory of Open Access Journals (Sweden)

    Alex Poznak

    2018-05-01

    Full Text Available The technological relevance of Al-Mg-Si alloys has been rapidly growing over the last decade. Of particular interest to current and future applications is the problematic negative effect of prior natural aging on subsequent artificial age hardening. The influence of natural aging is dependent on both processing and compositional variables and has origins that are far from well-understood. This work examines the hardenability of 6000 series alloys under a wide range of conditions, paying particular attention to the natural aging effect. Experimental variables include alloy composition (Mg + Si, Mg/Si, cooling rate after solutionization, and duration of prior natural aging. Hardenability was evaluated with full hardness and conductivity aging curves for each condition, as well as select Transmission Electron Microscopy (TEM. Results are discussed based on the actions of naturally aged solute clusters during artificial aging. In particular, a complex interaction between vacancy concentration, cluster stability, and precipitation driving force is suggested.

  5. ALGORITHMS FOR THE PROGRAMMING OF FOOTWEAR SOLES MOULDS ON WORKING POSTS OF INJECTION MACHINES

    Directory of Open Access Journals (Sweden)

    LUCA Cornelia

    2014-05-01

    Full Text Available The moulds stock necessary for realization in rhythmically conditions, a certain volume of footwear soles depends on some criterions such as: the range of soles for footwear volume daily realized, the sizes structure of those soles for footwear and, respectively, the sizes tally, the technological cycle for an used mould depending on the equipment efficiency, the provide necessity of spare moulds, the using and fixing conditions etc. From the efficiency point of view, the equipments may have two working posts, or more working posts (always, an even number, as 6, 12, 24, 40 posts. Footwear soles manufacturing takes into account the percentage distribution of the size numbers of the size series. When o portative assembly is used for the manufacturing of the footwear soles using the injection with “n” working posts, it is very important an optimum distribution of the working posts. The disadvantages of these equipments are the situations of the no equilibrium programming of the moulds, so that, in one time, some working posts spread out of the work. The paper presents some practical and theoretical solutions for moulds stock programming in portative assembly for footwear soles injection, so that an optimum equilibrium degree of the working posts will obtain

  6. Barriers and enabling factors for work-site physical activity programs: a qualitative examination.

    Science.gov (United States)

    Fletcher, Gena M; Behrens, Timothyh K; Domina, Lorie

    2008-05-01

    Work sites offer a productive setting for physical activity (PA) promoting interventions. Still, PA participation remains low. Thus, the purpose of this study was to examine the reasoning behind commonly reported barriers and enabling factors to participation in PA programs in a work-site setting. Employees from a large city government were recruited to participate in focus groups, stratified by white- and blue-collar occupations. Responses from open-ended questions about factors influencing participation in PA programs were audio recorded and transcribed verbatim. Resulting data were analyzed with open and axial coding. The sample consisted of 60 employees composing 9 focus groups. Although time was the most common barrier between both groups, white-collars workers responded that scheduling and work conflicts were the most common barrier concerning time. Blue-collar workers indicated shift work as their most common barrier. In addition, health was a significant enabling factor for both occupational categories. White-collar workers were much more concerned with appearances and were more highly motivated by weight loss and the hopefulness of quick results than were blue-collar workers. These findings are important in the understanding of PA as it relates to the reasoning behind participation in work-site programs in regard to occupational status.

  7. The association between school-to-work programs and school performance.

    Science.gov (United States)

    Welsh, Erin C; Appana, Savi; Anderson, Henry A; Zierold, Kristina M

    2014-02-01

    The School-to-Work (STW) Opportunities Act was passed to aid students in transitioning from education to employment by offering work-based learning opportunities. In the United States, 72% of high schools offer work-based learning opportunities for credit. This is the first study to describe school performance and school-based behaviors among students enrolled in STW programs and compare them with nonworking and other-working students. In 2003, a questionnaire was administered to five school districts and one large urban school in Wisconsin. Between 2008 and 2010, analyses were completed to characterize STW students and compare them with other students. Of the 6,519 students aged 14-18 years included in the analyses, 461 were involved in an STW program (7%), 3,108 were non-working (48%), and 2,950 were other-working students (45%). Compared with other students, STW students were less likely to have a grade point average >2.0, more likely to have three or more unexcused absences from school, and more likely to spend performance. School-to-Work students reported poorer academic performance and more unhealthy school-related behaviors compared with nonworking students and other-working students. Whereas many factors have a role in why students perform poorly in school, more research on students enrolled in STW programs is needed to understand whether participating has a negative impact on students' academic achievement. Copyright © 2014 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

  8. Duration of breast milk expression among working mothers enrolled in an employer-sponsored lactation program.

    Science.gov (United States)

    Ortiz, Joan; McGilligan, Kathryn; Kelly, Patricia

    2004-01-01

    Maternal employment has been one of the greatest barriers to breastfeeding. Women are increasingly solving this problem by expressing milk at work and taking it home to their infants. The objective was to determine duration of breast milk expression among working mothers enrolled in an employer-sponsored lactation program. Retrospective reviews were conducted on the lactation records of 462 women employed by 5 corporations in order to describe and characterize their experiences. The lactation program included the employees' choice of (a) a class on the benefits of breastfeeding; (b) services of a certified lactation consultant (CLC); and (c) private room in the workplace with equipment for pumping. Breastfeeding was initiated by 97.5% of the participants, with 57.8% continuing for at least 6 months. Of the 435 (94.2%) who returned to work after giving birth, 343 (78.9%) attempted pumping milk at work, and 336 (98%) were successful. They expressed milk in the workplace for a mean of 6.3 months (SD = 3.9, range 2 weeks to 21 months). The mean age of infants when the mothers stopped pumping at work was 9.1 months (SD = 4.1, range 1.9 to 25 months). Most of the women who pumped their milk at work were working full time (84.2%). The mean postnatal maternity leave was 2.8 months. The proportion of women who chose to pump at work was higher among women who were salaried than among those who were paid hourly wages (p < 0.01). Company-sponsored lactation programs can enable employed mothers to provide breast milk for their infants as long as they wish, thus helping the nation attain the Healthy People 2010 goals of 50% of mothers breastfeeding until their infants are 6-months-old.

  9. DMILL circuits. The hardened electronics decuples its performances

    International Nuclear Information System (INIS)

    Anon.

    1998-01-01

    Thanks to the DMILL (mixed logic-linear hardening) technology under development at the CEA, MHS, a French company specialized in the fabrication of integrated circuits now produces hardened electronic circuits ten times more resistant to radiations than its competitors. Outside the initial market (several thousands of circuits for the LHC particle accelerator of Geneva), a broad choice of applications is opened to this technology: national defense, space, civil nuclear and medical engineering, and high temperature applications. Short paper. (J.S.)

  10. Micromilling of hardened tool steel for mould making applications

    DEFF Research Database (Denmark)

    Bissacco, Giuliano; Hansen, Hans Nørgaard; De Chiffre, Leonardo

    2005-01-01

    geometries as those characterizing injection moulding moulds. The realization of the micromilling process in connection with hardened tool steel as workpiece material is particularly challenging. The low strength of the miniaturized end mills implies reduction and accurate control of the chip load which...... wear. This paper presents the micromilling process applied to the manufacturing of micro injection moulding moulds in hardened tool steel, presenting experimental evidence and possible solutions to the above-mentioned issues....

  11. Radiation hardening of metals irradiated by heavy ions

    International Nuclear Information System (INIS)

    Didyk, A.Yu.; Skuratov, V.A.; Mikhajlova, N.Yu.; Regel', V.R.

    1988-01-01

    The damage dose dependence in the 10 -4 -10 -2 dpa region of radiation hardening of Al, V, Ni, Cu irradiated by xenon ions with 124 MeV energy is investigated using the microhardness technique and transmission electron microscope. It is shown that the pure metals radiation hardening is stimulated for defects clusters with the typical size less than 5 nm, as in the case of neutron and the light charge ion irradiation

  12. Allergic contact dermatitis from resin hardeners during the manufacture of thermosetting coating paints.

    Science.gov (United States)

    Foulds, I S; Koh, D

    1992-02-01

    5 production operators from 2 factories manufacturing thermosetting coating paint developed work-related skin disorders within 12 months of the introduction of a new powdered paint product. All 5 workers were found to have allergic contact dermatitis from 2 epoxy resin hardeners, both of which were commercial preparations of triglycidyl isocyanurate (TGIC). 2 of the workers had concomitant sensitization to epoxy resin in the standard series and several of the epoxy resin preparations at the workplace. TGIC has been reported as a contact sensitizer both in persons producing the chemical and among end-users of TGIC-containing products. These 5 reported cases document allergic contact dermatitis from commercial TGIC among exposed workers during an intermediate process of powdered paint manufacture. The possibility of substituting this epoxy resin hardener with less sensitizing alternatives should be explored.

  13. Continuous monitoring of setting and hardening of mortar using FBG sensors

    Science.gov (United States)

    Lima, H.; Ribeiro, R.; Nogueira, R.; Silva, L.; Abe, I.; Pinto, J. L.

    2007-05-01

    The use of fibre Bragg grating sensors to study mortars' dimensional variations during the setting process is reported. When determining a mortar's potential to fissure, it's important to know its total retraction. This means it is necessary to know not only the mortar's retraction after hardened, but also to know how much it retracts during the plastic phase. This work presents a technique which allows to measure dimensional variations, either expansion or retraction, during the whole setting process. Temperature and strain evolution during both plastic and hardened phase of the mortar were obtained, allowing the determination of dimensional variations and setting times. Due to its high-speed, ease of implementation and low operation costs, this technique will allow to get a deeper knowledge of the effects of several additives on the mortar's behaviour, allowing to improve its mechanical properties through the determination of the proper chemical composition.

  14. Hardening behavior and texture evolution of TWIP steel during strain path change

    International Nuclear Information System (INIS)

    Wen, W; Borodachenkova, M; Pereira, A; Barlat, F; Gracio, J

    2015-01-01

    Polycrystal materials exhibit large changes in the flow stress and hardening behavior during the strain path change. Such changes are related with the crystallographic texture anisotropy and the rearrangement of dislocation structure during the pre-loading. These effects have been captured by a dislocation hardening model embedded in the visco-plastic selfconsistent (VPSC) model. In this work, the texture evolution and mechanical behavior of TWIP steel during the strain path change are investigated. The experimental studies are carried out on rolled TWIP steel sheet. The mechanical responses are obtained under tensile tests along rolling direction, followed by tension along the directions with 0° and 90° from the pre-loading direction. The simulated results of strain-stress curves and the texture evolution are in good agreement with the experimental data. (paper)

  15. Medios de enfriamiento para el temple // Means for Cooling During the Hardening Process

    Directory of Open Access Journals (Sweden)

    N. Caballero Stevens

    1999-07-01

    Full Text Available Los factores que rigen el proceso de temple son la temperatura, el tiempo de calentamiento y la velocidad de enfriamiento.Tradicionalmente, la variación de la velocidad de enfriamiento se ha logrado mediante la utilización de diferentes medios como elagua, aceites minerales, aceites orgánicos, metales fundidos y otros.En este trabajo, se presentan las características fundamentales de los medios convencionales y actuales empleados para elenfriamiento durante el temple.Palabras claves: Endurecimiento superficial, temple superficial, medios de enfriamiento._____________________________________________________________________AbstractFactors governing of the hardening process are temperature, heating time and cooling speed. Traditionally, the variation of thecooling time has been achieved by using different means such as water, mineral oils, molten metals, etc.In this work, the fundamental characteristics of the conventional and modern means developed for cooling during the hardeningprocess are presented.Key words: Hardening process, cooling means.

  16. Numerical model of phase transformation of steel C80U during hardening

    Directory of Open Access Journals (Sweden)

    T. Domański

    2007-12-01

    Full Text Available The article concerns numerical modelling of the phase transformations in solid state hardening of tool steel C80U. The transformations were assumed: initial structure – austenite, austenite – perlite, bainite and austenite – martensite. Model for evaluation of fractions of phases and their kinetics based on continuous heating diagram (CHT and continuous cooling diagram (CCT. The dilatometric tests on the simulator of thermal cycles were performed. The results of dilatometric tests were compared with the results of the test numerical simulations. In this way the derived models for evaluating phase content and kinetics of transformations in heating and cooling processes were verified. The results of numerical simulations confirm correctness of the algorithm that were worked out. In the numerical example the simulated estimation of the phase fraction in the hardened axisimmetrical element was performed.

  17. Effects of heat production on the temperature pattern and stresses on frictional hardening of cylindrical components

    International Nuclear Information System (INIS)

    Maksimovich, V.M.; Kratyuk, P.B.; Babei, Yu.I.; Maksimishin, M.D.

    1992-01-01

    Metal heating occurs during pulse hardening which influences the structure, state of strain, and physicomechanical properties, which in turn affects the viability. Difficulties exists in measuring the resulting temperature distributions because of the lag in existing methods. More accurate estimates of temperature distributions may often be obtained using theoretical methods, which involve solving coupled problems in the theory of elasticity and thermal conductivity. In this work, a planar contact case in thermoelasticity is considered for frictional hardening, in which the friction disk and the workpiece are represented as an elastic plunger and the body.It is assumed that the contact normal and tangential stresses are related by Coulomb's law. Also given is a method of solving which enables the definition of the thermoelastic state with a given accuracy in the contact region for high disk speeds. 5 refs., 2 figs., 1 tab

  18. Development of a radiation hardened ANDROS robot for environmental restoration and waste management operations

    International Nuclear Information System (INIS)

    Tulenko, J.S.; Youk, G.; Ekdahl, D.; Liu, H.; Zhou, H.; Phillips, K.; Sias, F.; Jones, S.; Cable, T.; Harvey, H.

    1995-01-01

    A radiation hardened and tolerant version of the ANDROS V-A and VI-A system has been developed by a team composed of engineers and scientists from REMOTEC, Inc. and the University of Florida. The final upgrade of the major control components to a hardness level greater than one megarad is detailed. Over twelve hundred parts were reviewed. The project has completed its Phase 1 and Phase 2 SBIR redesign with the upgrade of all control components. The facilities at the University of Florida which include a linear accelerator and multiple cobalt irradiators have provided the capability to perform the extensive testing required. The commercial production of this radiation hardened ANDROS makes available a mobile platform that can serve as a main work and inspection system for hazardous tasks facing the world nuclear industry

  19. Virtual reality based support system for layout planning and programming of an industrial robotic work cell.

    Directory of Open Access Journals (Sweden)

    Hwa Jen Yap

    Full Text Available Traditional robotic work cell design and programming are considered inefficient and outdated in current industrial and market demands. In this research, virtual reality (VR technology is used to improve human-robot interface, whereby complicated commands or programming knowledge is not required. The proposed solution, known as VR-based Programming of a Robotic Work Cell (VR-Rocell, consists of two sub-programmes, which are VR-Robotic Work Cell Layout (VR-RoWL and VR-based Robot Teaching System (VR-RoT. VR-RoWL is developed to assign the layout design for an industrial robotic work cell, whereby VR-RoT is developed to overcome safety issues and lack of trained personnel in robot programming. Simple and user-friendly interfaces are designed for inexperienced users to generate robot commands without damaging the robot or interrupting the production line. The user is able to attempt numerous times to attain an optimum solution. A case study is conducted in the Robotics Laboratory to assemble an electronics casing and it is found that the output models are compatible with commercial software without loss of information. Furthermore, the generated KUKA commands are workable when loaded into a commercial simulator. The operation of the actual robotic work cell shows that the errors may be due to the dynamics of the KUKA robot rather than the accuracy of the generated programme. Therefore, it is concluded that the virtual reality based solution approach can be implemented in an industrial robotic work cell.

  20. Virtual Reality Based Support System for Layout Planning and Programming of an Industrial Robotic Work Cell

    Science.gov (United States)

    Yap, Hwa Jen; Taha, Zahari; Md Dawal, Siti Zawiah; Chang, Siow-Wee

    2014-01-01

    Traditional robotic work cell design and programming are considered inefficient and outdated in current industrial and market demands. In this research, virtual reality (VR) technology is used to improve human-robot interface, whereby complicated commands or programming knowledge is not required. The proposed solution, known as VR-based Programming of a Robotic Work Cell (VR-Rocell), consists of two sub-programmes, which are VR-Robotic Work Cell Layout (VR-RoWL) and VR-based Robot Teaching System (VR-RoT). VR-RoWL is developed to assign the layout design for an industrial robotic work cell, whereby VR-RoT is developed to overcome safety issues and lack of trained personnel in robot programming. Simple and user-friendly interfaces are designed for inexperienced users to generate robot commands without damaging the robot or interrupting the production line. The user is able to attempt numerous times to attain an optimum solution. A case study is conducted in the Robotics Laboratory to assemble an electronics casing and it is found that the output models are compatible with commercial software without loss of information. Furthermore, the generated KUKA commands are workable when loaded into a commercial simulator. The operation of the actual robotic work cell shows that the errors may be due to the dynamics of the KUKA robot rather than the accuracy of the generated programme. Therefore, it is concluded that the virtual reality based solution approach can be implemented in an industrial robotic work cell. PMID:25360663

  1. What we remember affects how we see: spatial working memory steers saccade programming.

    Science.gov (United States)

    Wong, Jason H; Peterson, Matthew S

    2013-02-01

    Relationships between visual attention, saccade programming, and visual working memory have been hypothesized for over a decade. Awh, Jonides, and Reuter-Lorenz (Journal of Experimental Psychology: Human Perception and Performance 24(3):780-90, 1998) and Awh et al. (Psychological Science 10(5):433-437, 1999) proposed that rehearsing a location in memory also leads to enhanced attentional processing at that location. In regard to eye movements, Belopolsky and Theeuwes (Attention, Perception & Psychophysics 71(3):620-631, 2009) found that holding a location in working memory affects saccade programming, albeit negatively. In three experiments, we attempted to replicate the findings of Belopolsky and Theeuwes (Attention, Perception & Psychophysics 71(3):620-631, 2009) and determine whether the spatial memory effect can occur in other saccade-cuing paradigms, including endogenous central arrow cues and exogenous irrelevant singletons. In the first experiment, our results were the opposite of those in Belopolsky and Theeuwes (Attention, Perception & Psychophysics 71(3):620-631, 2009), in that we found facilitation (shorter saccade latencies) instead of inhibition when the saccade target matched the region in spatial working memory. In Experiment 2, we sought to determine whether the spatial working memory effect would generalize to other endogenous cuing tasks, such as a central arrow that pointed to one of six possible peripheral locations. As in Experiment 1, we found that saccade programming was facilitated when the cued location coincided with the saccade target. In Experiment 3, we explored how spatial memory interacts with other types of cues, such as a peripheral color singleton target or irrelevant onset. In both cases, the eyes were more likely to go to either singleton when it coincided with the location held in spatial working memory. On the basis of these results, we conclude that spatial working memory and saccade programming are likely to share common

  2. The Pennsylvania certified safety committee program: an evaluation of participation and effects on work injury rates.

    Science.gov (United States)

    Liu, Hangsheng; Burns, Rachel M; Schaefer, Agnes G; Ruder, Teague; Nelson, Christopher; Haviland, Amelia M; Gray, Wayne B; Mendeloff, John

    2010-08-01

    Since 1994, Pennsylvania, like several other states, has provided a 5% discount on workers' compensation insurance premiums for firms with a certified joint labor management safety committee. This study explored the factors affecting program participation and evaluated the effect of this program on work injuries. Using Pennsylvania unemployment insurance data (1996-2006), workers' compensation data (1998-2005), and the safety committee audit data (1999-2007), we conducted propensity score matching and regression analysis on the program's impact on injury rates. Larger firms, firms with higher injury rates, firms in high risk industries, and firms without labor unions were more likely to join the safety committee program and less likely to drop out of the program. The injury rates of participants did not decline more than the rates for non-participants; however, rates at participant firms with good compliance dropped more than the rates at participant firms with poor compliance. Firm size and prior injury rates are key predictors of program participation. Firms that complied with the requirement to train their safety committee members did experience reductions in injuries, but non-compliance with that and other requirements was so widespread that no overall impact of the program could be detected. Copyright 2010 Wiley-Liss, Inc.

  3. Columbia River Basin Fish and Wildlife Program Annual Implementation Work Plan for fiscal year 1992

    International Nuclear Information System (INIS)

    1991-09-01

    The Columbia River Basin Fish and Wildlife Program Annual Implementation Work Plan (AIWP) for Fiscal Year (FY) 1992 presents Bonneville Power Administration's (BPA) plans for implementing the Columbia River Basin Fish and Wildlife Program (Program) in FY 1992. The AIWP focuses on individual Action Items found in the 1987 Program for which BPA has determined that it has authority and responsibility to implement. Each of the entries in the AIWP includes objectives, background, progress to date in achieving the objectives, and a summary of plans for implementation in FY 1992. Most Action Items are implemented through one or more BPA-funded projects. Each Action Item entry is followed by a list of completed, ongoing, and planned projects, along with objectives, results, schedules, and milestones for each project. In October 1988, BPA and the Columbia Basin Fish and Wildlife Authority (CBFWA) initiated a collaborative and cooperative Implementation Planning Process (IPP). The IPP provided opportunities in FY 1991 for the fish and wildlife agencies. Tribes, and other interested parties to be involved in planning FY 1992 Program implementation. This planing process contributed to the development of this year's AIWP. The joint BPA/CBFWA IPP is expected to continue in FY 1992. The FY 1992 AIWP emphasizes continuation of 143 ongoing, or projected ongoing Program projects, tasks, or task orders, most of which involve protection, mitigation, or enhancement of anadromous fishery resources. The FY 1992 AIWP also contains 10 new Program projects or tasks that are planned to start in FY 1992

  4. Optimized radiation-hardened erbium doped fiber amplifiers for long space missions

    Science.gov (United States)

    Ladaci, A.; Girard, S.; Mescia, L.; Robin, T.; Laurent, A.; Cadier, B.; Boutillier, M.; Ouerdane, Y.; Boukenter, A.

    2017-04-01

    In this work, we developed and exploited simulation tools to optimize the performances of rare earth doped fiber amplifiers (REDFAs) for space missions. To describe these systems, a state-of-the-art model based on the rate equations and the particle swarm optimization technique is developed in which we also consider the main radiation effect on REDFA: the radiation induced attenuation (RIA). After the validation of this tool set by confrontation between theoretical and experimental results, we investigate how the deleterious radiation effects on the amplifier performance can be mitigated following adequate strategies to conceive the REDFA architecture. The tool set was validated by comparing the calculated Erbium-doped fiber amplifier (EDFA) gain degradation under X-rays at ˜300 krad(SiO2) with the corresponding experimental results. Two versions of the same fibers were used in this work, a standard optical fiber and a radiation hardened fiber, obtained by loading the previous fiber with hydrogen gas. Based on these fibers, standard and radiation hardened EDFAs were manufactured and tested in different operating configurations, and the obtained data were compared with simulation data done considering the same EDFA structure and fiber properties. This comparison reveals a good agreement between simulated gain and experimental data (vulnerability in terms of gain. The presented approach is a complementary and effective tool for hardening by device techniques and opens new perspectives for the applications of REDFAs and lasers in harsh environments.

  5. Microstructural evolution at high strain rates in solution-hardened interstitial free steels

    International Nuclear Information System (INIS)

    Uenishi, A.; Teodosiu, C.; Nesterova, E.V.

    2005-01-01

    Comprehensive transmission electron microscopical studies have been conducted for solution-hardened steels deformed at high (1000 s -1 ) and low (0.001 s -1 ) strain rates, in order to clarify the effects of strain rate and a jump in strain rate on the evolution of the microstructure and its connection with the mechanical response. It was revealed that the various types of microstructure, observed even within the same specimen, depend on the corresponding grain orientations and their evolution with progressive deformation depends on these microstructure types. At high strain rates, the dislocation density increases especially at low strains and the onset of dislocation organization is delayed. A jump in strain rate causes an increase of the dislocation density inside an organized structure. These results corroborated the mechanical behaviour at high strain rates after compensation for the cross-sectional reduction and temperature increase. The higher work-hardening rate at high strain rates could be connected to a delay in the dislocation organization. The high work-hardening rate just after a jump could be due to an increase of the density of dislocations distributed uniformly inside an organized structure

  6. Radiation-hardened bulk Si-gate CMOS microprocessor family

    International Nuclear Information System (INIS)

    Stricker, R.E.; Dingwall, A.G.F.; Cohen, S.; Adams, J.R.; Slemmer, W.C.

    1979-01-01

    RCA and Sandia Laboratories jointly developed a radiation-hardened bulk Si-gate CMOS technology which is used to fabricate the CDP-1800 series microprocessor family. Total dose hardness of 1 x 10 6 rads (Si) and transient upset hardness of 5 x 10 8 rads (Si)/sec with no latch up at any transient level was achieved. Radiation-hardened parts manufactured to date include the CDP-1802 microprocessor, the CDP-1834 ROM, the CDP-1852 8-bit I/O port, the CDP-1856 N-bit 1 of 8 decoder, and the TCC-244 256 x 4 Static RAM. The paper is divided into three parts. In the first section, the basic fundamentals of the non-hardened C 2 L technology used for the CDP-1800 series microprocessor parts is discussed along with the primary reasons for hardening this technology. The second section discusses the major changes in the fabrication sequence that are required to produce radiation-hardened devices. The final section details the electrical performance characteristics of the hardened devices as well as the effects of radiation on device performance. Also included in this section is a discussion of the TCC-244 256 x 4 Static RAM designed jointly by RCA and Sandia Laboratories for this application

  7. Reentry Program and Social Work Education: Training the Next Generation of Criminal Justice Social Workers.

    Science.gov (United States)

    Franke, Nancy D; Treglia, Dan; Cnaan, Ram A

    2017-01-01

    Social work plays a marginal role in opposing the trend of mass incarceration and high rates of recidivism, and social work education offers limited opportunities for students to specialize in working with people who are currently or were previously incarcerated. How to train students of social work to work against mass-incarceration is still challenging. The authors devised and implemented an in-school social service agency devoted to working with people pre and post release from a prison system. The agency is a field practicum setting where interested students study and practice reentry work. In this article, the authors describe and assess the educational merit of this in-school agency. Findings from surveys of students and alumni suggest that the program attained its educational goals of connecting classroom education to practice experience and training students for careers in the criminal justice system. The authors also discuss pending challenges. The experience of the Goldring Reentry Initiative suggests that by developing their own social work agencies, the authors may be able to heighten their students educational experience and expand their contribution to social work practice broadly.

  8. Employer-Based Programs to Support Breastfeeding Among Working Mothers: A Systematic Review.

    Science.gov (United States)

    Dinour, Lauren M; Szaro, Jacalyn M

    2017-04-01

    Many mothers experience barriers to maintaining a breastfeeding relationship with their infants upon returning to work and, consequently, terminate breastfeeding earlier than recommended or intended. As such, employers are in a unique position to help further increase breastfeeding rates, durations, and exclusivity. The purpose of this review is to examine the literature regarding employer-based programs, policies, and interventions to support breastfeeding among working mothers. A systematic literature search was conducted for peer-reviewed articles published before April 2016. Studies were included if they focused on workplace-based lactation/breastfeeding support programs, policies, or interventions to promote breastfeeding among employees. For inclusion, articles must have measured at least one outcome, such as breastfeeding duration, breastfeeding exclusivity, or employee satisfaction. Twenty-two articles were included, representing 10 different countries and both public- and private-sector employers, including governmental offices, schools, hospitals, manufacturing/industrial companies, and financial settings, among others. Providing a lactation space was the most common employer-based support accommodation studied, followed by breastfeeding breaks and comprehensive lactation support programs. The majority of studies analyzing these three support types found at least one positive breastfeeding and/or nonbreastfeeding outcome. This review suggests that maintaining breastfeeding while working is not only possible but also more likely when employers provide the supports that women need to do so. Although some employers may have more extensive breastfeeding support policies and practices than others, all employers can implement a breastfeeding support program that fits their company's budget and resources.

  9. Article Commentary: Becoming FASD Informed: Strengthening Practice and Programs Working with Women with FASD

    Directory of Open Access Journals (Sweden)

    Deborah Rutman

    2016-01-01

    Full Text Available There is growing appreciation among health and social care providers, especially those working in community-based programs with women or young people with substance use problems and/or who have experienced violence, maltreatment, or trauma, that a high number of their program participants may have been prenatally exposed to alcohol or have fetal alcohol spectrum disorder (FASD. This article provides a conceptualization of the key components of an FASD-informed approach. Drawing on the emerging literature and the author's research identifying the support needs and promising approaches in working with women, young adults, and adults with FASD, as well as evaluations of FASD-related programs, the article discusses what an FASD-informed approach is, why it is centrally important in working with women, adults, and young people who may have FASD, underlying principles of an FASD-informed approach, and examples of FASD-informed adaptations to practice, programming, and the physical environment. In this discussion, the benefits of using an FASD-informed approach for service providers and women living with FASD and their families, as well as conceptualization of FASD-informed policy and systems are highlighted.

  10. A work-site weight control program using financial incentives collected through payroll deduction.

    Science.gov (United States)

    Forster, J L; Jeffery, R W; Sullivan, S; Snell, M K

    1985-11-01

    In a work-site weight control program using a self-motivational program of financial incentives implemented through payroll deduction, 131 university employees chose weight loss goals (0 to 60 lb) and incentives (+5 to +30) to be deducted from each paycheck for six months. Return of incentive money was contingent on progress toward weight goals. Participants were assigned randomly to one of four protocols, involving group educational sessions v self-instruction only and required v optional attendance at weigh-ins and sessions. Overall, dropout rates (21.4%) and mean weight loss (12.2 lb) were encouraging, especially compared with those of other work-site programs. Weight loss was positively associated with attendance at weigh-ins and educational sessions. However, requiring attendance did not increase program effectiveness and seemed also to discourage enrollment among men. The weight control program was equally effective when offered with professionally led educational sessions or when accompanied by self-instructional materials only.

  11. A health system program to reduce work disability related to musculoskeletal disorders.

    Science.gov (United States)

    Abásolo, Lydia; Blanco, Margarita; Bachiller, Javier; Candelas, Gloria; Collado, Paz; Lajas, Cristina; Revenga, Marcelino; Ricci, Patricia; Lázaro, Pablo; Aguilar, Maria Dolores; Vargas, Emilio; Fernández-Gutiérrez, Benjamín; Hernández-García, César; Carmona, Loreto; Jover, Juan A

    2005-09-20

    Musculoskeletal disorders (MSDs) are a frequent cause of work disability, accounting for productivity losses in industrialized societies equivalent to 1.3% of the U.S. gross national product. To evaluate whether a population-based clinical program offered to patients with recent-onset work disability caused by MSDs is cost-effective. Randomized, controlled intervention study. The inclusion and follow-up periods each lasted 12 months. Three health districts in Madrid, Spain. All patients with MSD-related temporary work disability in 1998 and 1999. The control group received standard primary care management, with referral to specialized care if needed. The intervention group received a specific program, administered by rheumatologists, in which care was delivered during regular visits and included 3 main elements: education, protocol-based clinical management, and administrative duties. Efficacy variables were 1) days of temporary work disability and 2) number of patients with permanent work disability. All analyses were done on an intention-to-treat basis. 1,077 patients were included in the study, 7805 in the control group and 5272 in the intervention group, generating 16,297 episodes of MSD-related temporary work disability. These episodes were shorter in the intervention group than in the control group (mean, 26 days compared with 41 days; P < 0.001), and the groups had similar numbers of episodes per patient. Fewer patients received long-term disability compensation in the intervention group (n = 38 [0.7%]) than in the control group (n = 99 [1.3%]) (P < 0.005). Direct and indirect costs were lower in the intervention group than in the control group. To save 1 day of temporary work disability, 6.00 dollars had to be invested in the program. Each dollar invested generated a benefit of 11.00 dollars. The program's net benefit was in excess of 5 million dollars. The study was unblinded. Implementation of the program, offered to the general population, improves short

  12. Calculating Program for Decommissioning Work Productivity based on Decommissioning Activity Experience Data

    Energy Technology Data Exchange (ETDEWEB)

    Song, Chan-Ho; Park, Seung-Kook; Park, Hee-Seong; Moon, Jei-kwon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-10-15

    KAERI is performing research to calculate a coefficient for decommissioning work unit productivity to calculate the estimated time decommissioning work and estimated cost based on decommissioning activity experience data for KRR-2. KAERI used to calculate the decommissioning cost and manage decommissioning activity experience data through systems such as the decommissioning information management system (DECOMMIS), Decommissioning Facility Characterization DB System (DEFACS), decommissioning work-unit productivity calculation system (DEWOCS). In particular, KAERI used to based data for calculating the decommissioning cost with the form of a code work breakdown structure (WBS) based on decommissioning activity experience data for KRR-2.. Defined WBS code used to each system for calculate decommissioning cost. In this paper, we developed a program that can calculate the decommissioning cost using the decommissioning experience of KRR-2, UCP, and other countries through the mapping of a similar target facility between NPP and KRR-2. This paper is organized as follows. Chapter 2 discusses the decommissioning work productivity calculation method, and the mapping method of the decommissioning target facility will be described in the calculating program for decommissioning work productivity. At KAERI, research on various decommissioning methodologies of domestic NPPs will be conducted in the near future. In particular, It is difficult to determine the cost of decommissioning because such as NPP facility have the number of variables, such as the material of the target facility decommissioning, size, radiographic conditions exist.

  13. Calculating Program for Decommissioning Work Productivity based on Decommissioning Activity Experience Data

    International Nuclear Information System (INIS)

    Song, Chan-Ho; Park, Seung-Kook; Park, Hee-Seong; Moon, Jei-kwon

    2014-01-01

    KAERI is performing research to calculate a coefficient for decommissioning work unit productivity to calculate the estimated time decommissioning work and estimated cost based on decommissioning activity experience data for KRR-2. KAERI used to calculate the decommissioning cost and manage decommissioning activity experience data through systems such as the decommissioning information management system (DECOMMIS), Decommissioning Facility Characterization DB System (DEFACS), decommissioning work-unit productivity calculation system (DEWOCS). In particular, KAERI used to based data for calculating the decommissioning cost with the form of a code work breakdown structure (WBS) based on decommissioning activity experience data for KRR-2.. Defined WBS code used to each system for calculate decommissioning cost. In this paper, we developed a program that can calculate the decommissioning cost using the decommissioning experience of KRR-2, UCP, and other countries through the mapping of a similar target facility between NPP and KRR-2. This paper is organized as follows. Chapter 2 discusses the decommissioning work productivity calculation method, and the mapping method of the decommissioning target facility will be described in the calculating program for decommissioning work productivity. At KAERI, research on various decommissioning methodologies of domestic NPPs will be conducted in the near future. In particular, It is difficult to determine the cost of decommissioning because such as NPP facility have the number of variables, such as the material of the target facility decommissioning, size, radiographic conditions exist

  14. Developing precipitation hardenable high entropy alloys

    Science.gov (United States)

    Gwalani, Bharat

    High entropy alloys (HEAs) is a concept wherein alloys are constructed with five or more elements mixed in equal proportions; these are also known as multi-principle elements (MPEs) or complex concentrated alloys (CCAs). This PhD thesis dissertation presents research conducted to develop precipitation-hardenable high entropy alloys using a much-studied fcc-based equi-atomic quaternary alloy (CoCrFeNi). Minor additions of aluminium make the alloy amenable for precipitating ordered intermetallic phases in an fcc matrix. Aluminum also affects grain growth kinetics and Hall-Petch hardenability. The use of a combinatorial approach for assessing composition-microstructure-property relationships in high entropy alloys, or more broadly in complex concentrated alloys; using laser deposited compositionally graded AlxCrCuFeNi 2 (0 mechanically processed via conventional techniques. The phase stability and mechanical properties of these alloys have been investigated and will be presented. Additionally, the activation energy for grain growth as a function of Al content in these complex alloys has also been investigated. Change in fcc grain growth kinetic was studied as a function of aluminum; the apparent activation energy for grain growth increases by about three times going from Al0.1CoCrFeNi (3% Al (at%)) to Al0.3CoCrFeNi. (7% Al (at%)). Furthermore, Al addition leads to the precipitation of highly refined ordered L12 (gamma') and B2 precipitates in Al0.3CoCrFeNi. A detailed investigation of precipitation of the ordered phases in Al0.3CoCrFeNi and their thermal stability is done using atom probe tomography (APT), transmission electron microscopy (TEM) and Synchrotron X-ray in situ and ex situ analyses. The alloy strengthened via grain boundary strengthening following the Hall-Petch relationship offers a large increment of strength with small variation in grain size. Tensile strength of the Al0.3CoFeNi is increased by 50% on precipitation fine-scale gamma' precipitates

  15. Zinc coated sheet steel for press hardening

    Science.gov (United States)

    Ghanbari, Zahra N.

    Galvanized steels are of interest to enhance corrosion resistance of press-hardened steels, but concerns related to liquid metal embrittlement have been raised. The objective of this study was to assess the soak time and temperature conditions relevant to the hot-stamping process during which Zn penetration did or did not occur in galvanized 22MnB5 press-hardening steel. A GleebleRTM 3500 was used to heat treat samples using hold times and temperatures similar to those used in industrial hot-stamping. Deformation at both elevated temperature and room temperature were conducted to assess the coating and substrate behavior related to forming (at high temperature) and service (at room temperature). The extent of alloying between the coating and substrate was assessed on undeformed samples heat treated under similar conditions to the deformed samples. The coating transitioned from an α + Gamma1 composition to an α (bcc Fe-Zn) phase with increased soak time. This transition likely corresponded to a decrease in availability of Zn-rich liquid in the coating during elevated temperature deformation. Penetration of Zn into the substrate sheet in the undeformed condition was not observed for any of the processing conditions examined. The number and depth of cracks in the coating and substrate steel was also measured in the hot-ductility samples. The number of cracks appeared to increase, while the depth of cracks appeared to decrease, with increasing soak time and increasing soak temperature. The crack depth appeared to be minimized in the sample soaked at the highest soak temperature (900 °C) for intermediate and extended soak times (300 s or 600 s). Zn penetration into the substrate steel was observed in the hot-ductility samples soaked at each hold temperature for the shortest soak time (10 s) before being deformed at elevated temperature. Reduction of area and elongation measurements showed that the coated sample soaked at the highest temperature and longest soak time

  16. Extracting material response from simple mechanical tests on hardening-softening-hardening viscoplastic solids

    Science.gov (United States)

    Mohan, Nisha

    Compliant foams are usually characterized by a wide range of desirable mechanical properties. These properties include viscoelasticity at different temperatures, energy absorption, recoverability under cyclic loading, impact resistance, and thermal, electrical, acoustic and radiation-resistance. Some foams contain nano-sized features and are used in small-scale devices. This implies that the characteristic dimensions of foams span multiple length scales, rendering modeling their mechanical properties difficult. Continuum mechanics-based models capture some salient experimental features like the linear elastic regime, followed by non-linear plateau stress regime. However, they lack mesostructural physical details. This makes them incapable of accurately predicting local peaks in stress and strain distributions, which significantly affect the deformation paths. Atomistic methods are capable of capturing the physical origins of deformation at smaller scales, but suffer from impractical computational intensity. Capturing deformation at the so-called meso-scale, which is capable of describing the phenomenon at a continuum level, but with some physical insights, requires developing new theoretical approaches. A fundamental question that motivates the modeling of foams is `how to extract the intrinsic material response from simple mechanical test data, such as stress vs. strain response?' A 3D model was developed to simulate the mechanical response of foam-type materials. The novelty of this model includes unique features such as the hardening-softening-hardening material response, strain rate-dependence, and plastically compressible solids with plastic non-normality. Suggestive links from atomistic simulations of foams were borrowed to formulate a physically informed hardening material input function. Motivated by a model that qualitatively captured the response of foam-type vertically aligned carbon nanotube (VACNT) pillars under uniaxial compression [2011,"Analysis of

  17. NINJA: a noninvasive framework for internal computer security hardening

    Science.gov (United States)

    Allen, Thomas G.; Thomson, Steve

    2004-07-01

    Vulnerabilities are a growing problem in both the commercial and government sector. The latest vulnerability information compiled by CERT/CC, for the year ending Dec. 31, 2002 reported 4129 vulnerabilities representing a 100% increase over the 2001 [1] (the 2003 report has not been published at the time of this writing). It doesn"t take long to realize that the growth rate of vulnerabilities greatly exceeds the rate at which the vulnerabilities can be fixed. It also doesn"t take long to realize that our nation"s networks are growing less secure at an accelerating rate. As organizations become aware of vulnerabilities they may initiate efforts to resolve them, but quickly realize that the size of the remediation project is greater than their current resources can handle. In addition, many IT tools that suggest solutions to the problems in reality only address "some" of the vulnerabilities leaving the organization unsecured and back to square one in searching for solutions. This paper proposes an auditing framework called NINJA (acronym for Network Investigation Notification Joint Architecture) for noninvasive daily scanning/auditing based on common security vulnerabilities that repeatedly occur in a network environment. This framework is used for performing regular audits in order to harden an organizations security infrastructure. The framework is based on the results obtained by the Network Security Assessment Team (NSAT) which emulates adversarial computer network operations for US Air Force organizations. Auditing is the most time consuming factor involved in securing an organization's network infrastructure. The framework discussed in this paper uses existing scripting technologies to maintain a security hardened system at a defined level of performance as specified by the computer security audit team. Mobile agents which were under development at the time of this writing are used at a minimum to improve the noninvasiveness of our scans. In general, noninvasive

  18. Collaborative work as a didactic strategy for teaching/learning programming: a systematic literature review

    Directory of Open Access Journals (Sweden)

    Oscar Revelo-Sanchez

    2018-01-01

    Full Text Available The incorporation of Collaborative Work into programming courses has been identified as a potential strategy that could maximize student participation and have a positive impact on learning. In the consulted sources, no study has been found to collect and analyze the results of research on this subject using a systematic method. To try to fill this gap, a systematic literature review was conducted with the aim of summarizing the studies on the use of Collaborative Work as a didactic strategy for teaching/learning programming. Initially, through a search in four (4 databases of scientific publications, 95 studies published in the last five (5 years were obtained. After careful analysis of each one of them, only 40 were found to meet the review requirements. This analysis resulted in the synthesis of eleven (11 Collaborative Learning Techniques (CLT that implement such strategy. Subsequently, they were grouped into 19 common names of strategies found in the documents, i.e. the collaborative strategies or techniques associated with each study. The review also showed a significant amount of contributions from the research community that constitute an important basis for future work. This demonstrates that Collaborative Work is increasingly consolidated as a valid and relevant didactic strategy, not only in programming teaching/learning, but also in other areas of knowledge including computer science.

  19. Surface finishing and levelling of thermomechanically hardened rolled steel

    International Nuclear Information System (INIS)

    Grosval'd, V.G.; Bashchenko, A.P.; Grishkov, A.I.; Gutnik, M.V.; Kanevskij, B.L.; Nikozov, A.I.; Sedov, N.D.; Prosin, K.A.; Safonov, L.I.

    1975-01-01

    The finishing of high-strength merchant shapes from alloy steel was tried out under industrial conditions with the equipment of metallurgical plants. After thermomechanical hardening in the production line of the rolling mill, 30KhGSN2A and 40Kh1NVA steel rounds 32 and 31 mm in diameter were straightened on a two-roller straightening machine designed by the All-Union Scientific Research Institute for Metallurgical Machinery (VNII Metmash). This made possible subsequent turning and grinding of the rods. The conditions of straightening, turning and grinding have been worked so as to obtain thermomechanically strengthened and ground rolled products approximating the gauged and ground metal in shape geometry and surface finish. It is shown that the labour-consuming operation of turning can be eliminated by reducing the machining pass of the rolled product, and this lowers the labour required for the finishing operations by 75%. After grinding with 40- and 25-grain abrasive wheels, high strength rolled shapes were obtained with a diameter of 30-0.20 mm and a surface finish of class 6-5 satisfying the technical specifications. (author)

  20. The 80-hour work week for residents: views from obstetric and gynecology program directors.

    Science.gov (United States)

    Janoo, Jabin; Hashmi, Mahreen; Seybold, Dara J; Shapiro, Robert; Calhoun, Byron C; Bush, Stephen H

    2014-01-01

    In 2003, the Accreditation Council for Graduate Medical Education mandated an 80-hour work week restriction for residency programs. We examined program directors' views on how this mandate affects the education of Obstetrics and Gynecology residents. A 25 question survey was administered via Survey Monkey to Obstetrics and Gynecology program directors in the United States over three months in 2011. Fifty program directors (response rate of 28%) completed it with more men (62%) than women (38%) respondents. Overall, only 28% (14/50) responded that the program had improved, with significantly fewer men (5/14; 16.1%) than women (47.4% 9/19; p performance objectives and in the CREOG scores, with the improvement ranging from 8% to 12%. In fact, while we observed the percentage of women directors reporting improvement in patient care and interpersonal and communication skills significantly higher compared with their male counterparts, the majority of women still reported either no improvement or a decline in these areas. Though our sample size was small, we found some significant difference between the views of male and female program directors. Both groups nonetheless responded with the majority with a decline or no change rather than a perceived improvement in any of the educational endeavors studied.

  1. Return-to-Work Program for Injured Workers: Factors of Successful Return to Employment.

    Science.gov (United States)

    Awang, Halimah; Shahabudin, Sharifah Muhairah; Mansor, Norma

    2016-11-01

    This study examined the factors of successful return to employment among participants in the return to work program (RTW) following work-related injury. Data were obtained from the Social Security Organization database containing 9850 injured workers who underwent RTW in 2010 to 2013. About 65% had successfully returned to employment. Significant factors of successful return include gender, employer interest, motivation, age, intervention duration, and type of injury. Male and motivated employees were more likely to return to employment compared with female and unmotivated employees, respectively. Participants from interested employers were 23.22 times more likely to return to work than those from uninterested employers, whereas participants whose intervention period exceeded 5 months were 41% less likely to return to work compared with those whose intervention period was within 3 months. Appropriate strategy and enhanced collaboration between the stakeholders would improve the proportion of successful return to employment. © 2016 APJPH.

  2. Collecting costs of community prevention programs: communities putting prevention to work initiative.

    Science.gov (United States)

    Khavjou, Olga A; Honeycutt, Amanda A; Hoerger, Thomas J; Trogdon, Justin G; Cash, Amanda J

    2014-08-01

    Community-based programs require substantial investments of resources; however, evaluations of these programs usually lack analyses of program costs. Costs of community-based programs reported in previous literature are limited and have been estimated retrospectively. To describe a prospective cost data collection approach developed for the Communities Putting Prevention to Work (CPPW) program capturing costs for community-based tobacco use and obesity prevention strategies. A web-based cost data collection instrument was developed using an activity-based costing approach. Respondents reported quarterly expenditures on labor; consultants; materials, travel, and services; overhead; partner efforts; and in-kind contributions. Costs were allocated across CPPW objectives and strategies organized around five categories: media, access, point of decision/promotion, price, and social support and services. The instrument was developed in 2010, quarterly data collections took place in 2011-2013, and preliminary analysis was conducted in 2013. Preliminary descriptive statistics are presented for the cost data collected from 51 respondents. More than 50% of program costs were for partner organizations, and over 20% of costs were for labor hours. Tobacco communities devoted the majority of their efforts to media strategies. Obesity communities spent more than half of their resources on access strategies. Collecting accurate cost information on health promotion and disease prevention programs presents many challenges. The approach presented in this paper is one of the first efforts successfully collecting these types of data and can be replicated for collecting costs from other programs. Copyright © 2014 American Journal of Preventive Medicine. All rights reserved.

  3. TRAC-Monterey FY16 Work Program Development and Report of Research Elicitation

    Science.gov (United States)

    2016-01-01

    any changes to priorities or additional projects that require immediate research. Work Program; Research Elicitation Unclassified UU UU UU UU 35 MAJ...conduct analysis for the Army. 1 Marks, Chris, Nesbitt, Peter. TRAC FY14 Research Requirements Elicitation . Technical Report TRAC-M-TM-13-059. 700 Dyer... Requirements Elicitation Interviews Interview Guide: 1. Describe a research requirement in the areas of topics, techniques, and methodologies. 2

  4. Radiation effects on radiation-hardened KU and KS-4V optical fibres

    International Nuclear Information System (INIS)

    Ivanov, A.A.; Tugarinov, S.N.; Kaschuck, Y.A.; Krasilnikov, A.V.; Bender, S.E.

    1999-01-01

    The aim of this work was to test the un-pretreated and the hardened (H 2 -loaded and pre-irradiated) KS-4V and KU optical fibres in reactor environment by in-situ measurements of both the radiation-induced loss and the luminescence in the visible spectral region. Both the radio-luminescent and the transmission spectra were in-situ detected during irradiation by charge-coupled-device (CCD) linear detector in the visible spectral region of 400 to 700 nm. The radiation induced loss spectra at the fast neutron fluence of 2*10 6 n/cm 2 shows the hardened, H 2 -loading and pre-irradiating effects in the both KU and KS-4V fibres. KU un-pretreated fibre shows a big radiation absorption band of non-bridging oxygen centered at the wavelength of 630 nm. It appears that the KS-4V hardened fibre has a specific point in the loss spectrum in the vicinity of 460 nm. Other measurements were performed, particularly after reactor shutdown and at 3 different neutron fluences with constant neutron flux after restarting

  5. Microstructure and age-hardening effects of aluminium alloys with additions of scandium and zirconium

    Energy Technology Data Exchange (ETDEWEB)

    Galun, R.; Mordike, B.L. [Inst. fuer Werkstoffkunde und Werkstofftechnik, Technische Univ. Clausthal, Clausthal-Zellerfeld (Germany); Maiwald, T.; Smola, B. [Zentrum fuer Funktionswerkstoffe GmbH, Clausthal-Zellerfeld (Germany); Mergen, R.; Manner, M.; Uitz, W. [Miba Gleitlager GmbH, Laakirchen (Australia)

    2004-12-01

    The aim of the work presented in this report was to produce age-hardenable aluminium alloys containing scandium and zirconium by a casting process with similar cooling conditions like an industrial casting process. Microstructure, precipitation structure and age-hardening response of different alloys with up to 0.4 wt.% Sc and Zr were investigated. Age-hardening experiments from the as-cast condition without solution annealing showed a significant increase of hardness of about 100% for Sc-rich alloys and of 50% for Zr-rich alloys compared to the as-cast condition. TEM investigations revealed the formation of precipitates of ternary Al{sub 3}(Sc{sub x}Zr{sub 1-x}) phases with a cubic cP4 crystal structure. In addition to the strengthening effect, a high thermal stability especially of the precipitates in Zr-rich alloys up to 400 C let these alloys look very promising for high-temperature applications. (orig.)

  6. Simulating irradiation hardening in tungsten under fast neutron irradiation including Re production by transmutation

    Science.gov (United States)

    Huang, Chen-Hsi; Gilbert, Mark R.; Marian, Jaime

    2018-02-01

    Simulations of neutron damage under fusion energy conditions must capture the effects of transmutation, both in terms of accurate chemical inventory buildup as well as the physics of the interactions between transmutation elements and irradiation defect clusters. In this work, we integrate neutronics, primary damage calculations, molecular dynamics results, Re transmutation calculations, and stochastic cluster dynamics simulations to study neutron damage in single-crystal tungsten to mimic divertor materials. To gauge the accuracy and validity of the simulations, we first study the material response under experimental conditions at the JOYO fast reactor in Japan and the High Flux Isotope Reactor at Oak Ridge National Laboratory, for which measurements of cluster densities and hardening levels up to 2 dpa exist. We then provide calculations under expected DEMO fusion conditions. Several key mechanisms involving Re atoms and defect clusters are found to govern the accumulation of irradiation damage in each case. We use established correlations to translate damage accumulation into hardening increases and compare our results to the experimental measurements. We find hardening increases in excess of 5000 MPa in all cases, which casts doubts about the integrity of W-based materials under long-term fusion exposure.

  7. Empowering certified nurse's aides to improve quality of work life through a team communication program.

    Science.gov (United States)

    Howe, Erin E

    2014-01-01

    The purpose of this pilot study was to explore the impact of a certified nurse's aide (CNA)-led interdisciplinary teamwork and communication intervention on perceived quality of work environment and six-month job intentions. CNAs are frequently excluded from team communication and decision-making, which often leads to job dissatisfaction with high levels of staff turnover. Using a mixed quantitative and qualitative approach with pre- post-program design, the intervention utilized the strategy of debriefing from the national patient safety initiative, TeamSTEPPS. Inherent in the program design, entitled Long Term Care (LTC) Team Talk, was the involvement of the CNAs in the development of the intervention as an empowering process on two wings of a transitional care unit in a long-term care facility in upstate NY. CNAs' perceptions of work environment quality were measured using a Quality of Work Life (QWL) instrument. Additionally, job turnover intent within six months was assessed. Results indicated improved scores on nearly all QWL subscales anticipated to be impacted, and enhanced perceived empowerment of the CNAs on each wing albeit through somewhat different experiential processes. The program is highly portable and can potentially be implemented in a variety of long-term care settings. Copyright © 2014 Mosby, Inc. All rights reserved.

  8. Surface hardening of 30CrMnSiA steel using continuous electron beam

    Science.gov (United States)

    Fu, Yulei; Hu, Jing; Shen, Xianfeng; Wang, Yingying; Zhao, Wansheng

    2017-11-01

    30CrMnSiA high strength low alloy (HSLA) carbon structural steel is typically applied in equipment manufacturing and aerospace industries. In this work, the effects of continuous electron beam treatment on the surface hardening and microstructure modifications of 30CrMnSiA are investigated experimentally via a multi-purpose electron beam machine Pro-beam system. Micro hardness value in the electron beam treated area shows a double to triple increase, from 208 HV0.2 on the base metal to 520 HV0.2 on the irradiated area, while the surface roughness is relatively unchanged. Surface hardening parameters and mechanisms are clarified by investigation of the microstructural modification and the phase transformation both pre and post irradiation. The base metal is composed of ferrite and troostite. After continuous electron beam irradiation, the micro structure of the electron beam hardened area is composed of acicular lower bainite, feathered upper bainite and part of lath martensite. The optimal input energy density for 30CrMnSiA steel in this study is of 2.5 kJ/cm2 to attain the proper hardened depth and peak hardness without the surface quality deterioration. When the input irradiation energy exceeds 2.5 kJ/cm2 the convective mixing of the melted zone will become dominant. In the area with convective mixing, the cooling rate is relatively lower, thus the micro hardness is lower. The surface quality will deteriorate. Chemical composition and surface roughness pre and post electron beam treatment are also compared. The technology discussed give a picture of the potential of electron beam surface treatment for improving service life and reliability of the 30CrMnSiA steel.

  9. Efficient simulation of press hardening process through integrated structural and CFD analyses

    International Nuclear Information System (INIS)

    Palaniswamy, Hariharasudhan; Mondalek, Pamela; Wronski, Maciek; Roy, Subir

    2013-01-01

    Press hardened steel parts are being increasingly used in automotive structures for their higher strength to meet safety standards while reducing vehicle weight to improve fuel consumption. However, manufacturing of sheet metal parts by press hardening process to achieve desired properties is extremely challenging as it involves complex interaction of plastic deformation, metallurgical change, thermal distribution, and fluid flow. Numerical simulation is critical for successful design of the process and to understand the interaction among the numerous process parameters to control the press hardening process in order to consistently achieve desired part properties. Until now there has been no integrated commercial software solution that can efficiently model the complete process from forming of the blank, heat transfer between the blank and tool, microstructure evolution in the blank, heat loss from tool to the fluid that flows through water channels in the tools. In this study, a numerical solution based on Altair HyperWorks® product suite involving RADIOSS®, a non-linear finite element based structural analysis solver and AcuSolve®, an incompressible fluid flow solver based on Galerkin Least Square Finite Element Method have been utilized to develop an efficient solution for complete press hardening process design and analysis. RADIOSS is used to handle the plastic deformation, heat transfer between the blank and tool, and microstructure evolution in the blank during cooling. While AcuSolve is used to efficiently model heat loss from tool to the fluid that flows through water channels in the tools. The approach is demonstrated through some case studies

  10. `Unthinkable' Selves: Identity boundary work in a summer field ecology enrichment program for diverse youth

    Science.gov (United States)

    Carlone, Heidi B.; Huffling, Lacey D.; Tomasek, Terry; Hegedus, Tess A.; Matthews, Catherine E.; Allen, Melony H.; Ash, Mary C.

    2015-07-01

    The historical under-representation of diverse youth in environmental science education is inextricably connected to access and identity-related issues. Many diverse youth with limited previous experience to the outdoors as a source for learning and/or leisure may consider environmental science as 'unthinkable'. This is an ethnographic study of 16 diverse high school youths' participation, none of who initially fashioned themselves as 'outdoorsy' or 'animal people', in a four-week summer enrichment program focused on herpetology (study of reptiles and amphibians). To function as 'good' participants, youth acted in ways that placed them well outside their comfort zones, which we labeled as identity boundary work. Results highlight the following cultural tools, norms, and practices that enabled youths' identity boundary work: (1) boundary objects (tools regularly used in the program that facilitated youths' engagement with animals and nature and helped them work through fear or discomfort); (2) time and space (responsive, to enable adaptation to new environments, organisms, and scientific field techniques); (3) social support and collective agency; and (4) scientific and anecdotal knowledge and skills. Findings suggest challenges to commonly held beliefs about equitable pedagogy, which assumes that scientific practices must be thinkable and/or relevant before youth engage meaningfully. Further, findings illustrate the ways that fear, in small doses and handled with empathy, may become a resource for youths' connections to animals, nature, and science. Finally, we propose that youths' situated identity boundary work in the program may have the potential to spark more sustained identity work, given additional experiences and support.

  11. How Does The Universe Work? The Physics Of The Cosmos Program (PCOS)

    Science.gov (United States)

    Sambruna, Rita M.

    2011-09-01

    The Physics of the Cosmos (PCOS) program incorporates cosmology, high-energy astrophysics, and fundamental physics projects aimed at addressing central questions about the nature of complex astrophysical phenomena such as black holes, neutron stars, dark energy, and gravitational waves. Its overarching theme is, How does the Universe work? PCOS includes a suite of operating (Chandra, Fermi, Planck, XMM-Newton, INTEGRAL) and future missions across the electromagnetic spectrum and beyond, which are in concept development and/or formulation. The PCOS program directly supports development of intermediate TRL (4-6) technology relevant to future missions through the Strategic Astrophysics Technology (SAT) program, as well as data analysis, theory, and experimental astrophysics via other R&A avenues (e.g., ADAP, ATP). The Einstein Fellowship is a vital and vibrant PCOS component funded by the program. PCOS receives community input via its Program Analysis Group, the PhysPAG (www.pcos.gsfc.nasa.gov/physpag.php), whose membership and meetings are open to the community at large. In this poster, we describe the detailed science questions addressed within PCOS, with special emphasis on future opportunities. Details about the PhysPAG operations and functions will be provided, as well as an update on future meetings.

  12. Ten years of work in Cuban Program to children from areas affected of Chernobyl accidents

    International Nuclear Information System (INIS)

    Garcia, Omar; Medina J, Julio

    2001-01-01

    In April of 2000 the Cuban program for specialised medical attention to children from areas affected by the radioactive contamination from the Chernobyl accident completed 10 years of work. In the program had been assisted more than 18 000 children and adults, among them 50 Brazilians related with the Goiania accident. A group of medical procedures and dosimetric, biomedical and psychological investigations have been carried out in the program. The main significant medical attention activities are the treatment of haematological disorders, among them, 120 leukaemia, the realisation of bone marrow transplants and the treatment of endocrinological and neoplasic illnesses. The dosimetric studies has allowed to create a database that accumulates information about internal contamination for 137Cs, internal, external, and total doses, of 7000 children. The analysis of the behaviour of all the medical information that is generated in the program in function of the contamination of the land and of the internal contamination of the children is also performed. The program has accumulated an experience of interest for physicians, psychologists and radiological emergencies experts.(author)

  13. Career Advancement and Work Support Services on the Job: Implementing the Fort Worth Work Advancement and Support Center Program. Executive Summary

    Science.gov (United States)

    Schultz, Caroline; Seith, David

    2011-01-01

    The Work Advancement and Support Center (WASC) program in Fort Worth was part of a demonstration that is testing innovative strategies to help increase the income of low-wage workers, who make up a large segment of the U.S. workforce. The program offered services to help workers stabilize their employment, improve their skills, and increase their…

  14. A two-year follow-up on a program theory of return to work intervention.

    Science.gov (United States)

    Jensen, Anne Grete Claudi

    2013-01-01

    Validation of a salutogenic theory for return to work (RTW) and an associated program process theory. A longitudinal non-randomized one-year trial study design was used with a two-year follow-up and with comparison to a reference group. Changes in attitudes and active behaviour in the intervention group and at the workplace were supported by cognitive and behavioural approaches. The intervention group included 118 unskilled Danish public employees and privately employed house-cleaners on sick leave due to musculoskeletal and/or common mental illnesses. Significant improvements of work ability index and perceived health (SF36 subgroups) were reported. A significantly higher RTW and a shorter sick leave than in the reference group also emerged. Positive predictors of RTW were keeping the pre-sick-leave job and improving work ability index and physical impairment/role physical. Decline in self-efficacy was a negative predictor. Support for the theory and associated program process theory was found. The intervention seemed to influence RTW and the employees' attitudes, behaviour and health by affecting comprehensibility, meaningfulness and manageability. Sustainable RTW emerged from a synergism of support from the work place and improved personal resources, especially such as concern mental health. The approach is consistent with integrating health promotion in RTW.

  15. Influence of Hardening Model on Weld Residual Stress Distribution

    Energy Technology Data Exchange (ETDEWEB)

    Mullins, Jonathan; Gunnars, Jens (Inspecta Technology AB, Stockholm (Sweden))

    2009-06-15

    This study is the third stage of a project sponsored by the Swedish Radiation Safety Authority (SSM) to improve the weld residual stress modelling procedures currently used in Sweden. The aim of this study was to determine which material hardening model gave the best agreement with experimentally measured weld residual stress distributions. Two girth weld geometries were considered: 19mm and 65mm thick girth welds with Rin/t ratios of 10.5 and 2.8, respectively. The FE solver ABAQUS Standard v6.5 was used for analysis. As a preliminary step some improvements were made to the welding simulation procedure used in part one of the project. First, monotonic stress strain curves and a mixed isotropic/kinematic hardening model were sourced from the literature for 316 stainless steel. Second, more detailed information was obtained regarding the geometry and welding sequence for the Case 1 weld (compared with phase 1 of this project). Following the preliminary step, welding simulations were conducted using isotropic, kinematic and mixed hardening models. The isotropic hardening model gave the best overall agreement with experimental measurements; it is therefore recommended for future use in welding simulations. The mixed hardening model gave good agreement for predictions of the hoop stress but tended to under estimate the magnitude of the axial stress. It must be noted that two different sources of data were used for the isotropic and mixed models in this study and this may have contributed to the discrepancy in predictions. When defining a mixed hardening model it is difficult to delineate the relative contributions of isotropic and kinematic hardening and for the model used it may be that a greater isotropic hardening component should have been specified. The kinematic hardening model consistently underestimated the magnitude of both the axial and hoop stress and is not recommended for use. Two sensitivity studies were also conducted. In the first the effect of using a

  16. Influence of Hardening Model on Weld Residual Stress Distribution

    International Nuclear Information System (INIS)

    Mullins, Jonathan; Gunnars, Jens

    2009-06-01

    This study is the third stage of a project sponsored by the Swedish Radiation Safety Authority (SSM) to improve the weld residual stress modelling procedures currently used in Sweden. The aim of this study was to determine which material hardening model gave the best agreement with experimentally measured weld residual stress distributions. Two girth weld geometries were considered: 19mm and 65mm thick girth welds with Rin/t ratios of 10.5 and 2.8, respectively. The FE solver ABAQUS Standard v6.5 was used for analysis. As a preliminary step some improvements were made to the welding simulation procedure used in part one of the project. First, monotonic stress strain curves and a mixed isotropic/kinematic hardening model were sourced from the literature for 316 stainless steel. Second, more detailed information was obtained regarding the geometry and welding sequence for the Case 1 weld (compared with phase 1 of this project). Following the preliminary step, welding simulations were conducted using isotropic, kinematic and mixed hardening models. The isotropic hardening model gave the best overall agreement with experimental measurements; it is therefore recommended for future use in welding simulations. The mixed hardening model gave good agreement for predictions of the hoop stress but tended to under estimate the magnitude of the axial stress. It must be noted that two different sources of data were used for the isotropic and mixed models in this study and this may have contributed to the discrepancy in predictions. When defining a mixed hardening model it is difficult to delineate the relative contributions of isotropic and kinematic hardening and for the model used it may be that a greater isotropic hardening component should have been specified. The kinematic hardening model consistently underestimated the magnitude of both the axial and hoop stress and is not recommended for use. Two sensitivity studies were also conducted. In the first the effect of using a

  17. Effectiveness of a Multilevel Workplace Health Promotion Program on Vitality, Health, and Work-Related Outcomes.

    Science.gov (United States)

    Hendriksen, Ingrid J M; Snoijer, Mirjam; de Kok, Brenda P H; van Vilsteren, Jeroen; Hofstetter, Hedwig

    2016-06-01

    Evaluation of the effectiveness of a workplace health promotion program on employees' vitality, health, and work-related outcomes, and exploring the influence of organizational support and the supervisors' role on these outcomes. The 5-month intervention included activities at management, team, and individual level targeting self-management to perform healthy behaviors: a kick-off session, vitality training sessions, workshops, individual coaching, and intervision. Outcome measures were collected using questionnaires, health checks, and sickness absence data at baseline, after the intervention and at 10 months follow-up. For analysis linear and generalized mixed models were used. Vitality, work performance, sickness absence, and self-management significantly improved. Good organizational support and involved supervisors were significantly associated with lower sickness absence. Including all organizational levels and focusing on increasing self-management provided promising results for improving vitality, health, and work-related outcomes.

  18. Effect of the Danish return-to-work program on long-term sickness absence

    DEFF Research Database (Denmark)

    Poulsen, Otto M; Aust, Birgit; Bjørner, Jakob

    2014-01-01

    participant receiving ordinary sickness benefit management (OSM). Study participants were working-age adults receiving long-term (≥8 weeks or more) benefits, included regardless of reason for sickness absence or employment status. Each beneficiary was followed-up for a maximum period of 52 weeks. Cox......OBJECTIVES: The aim of this study was to evaluate the effect of the Danish return-to-work (RTW) program on long-term sickness absence in a randomized controlled trial in three municipalities. METHODS: The intervention group comprised 1948 participants while the control group comprised 1157...... proportional hazards model was used to estimate hazard ratios (HR) for return to work (RTW) with 95% confidence intervals (95% CI). RESULTS: The intervention effect differed significantly between the municipalities (P=0.00005). In one municipality (M2) the intervention resulted in a statistically significant...

  19. General analytical shakedown solution for structures with kinematic hardening materials

    Science.gov (United States)

    Guo, Baofeng; Zou, Zongyuan; Jin, Miao

    2016-09-01

    The effect of kinematic hardening behavior on the shakedown behaviors of structure has been investigated by performing shakedown analysis for some specific problems. The results obtained only show that the shakedown limit loads of structures with kinematic hardening model are larger than or equal to those with perfectly plastic model of the same initial yield stress. To further investigate the rules governing the different shakedown behaviors of kinematic hardening structures, the extended shakedown theorem for limited kinematic hardening is applied, the shakedown condition is then proposed, and a general analytical solution for the structural shakedown limit load is thus derived. The analytical shakedown limit loads for fully reversed cyclic loading and non-fully reversed cyclic loading are then given based on the general solution. The resulting analytical solution is applied to some specific problems: a hollow specimen subjected to tension and torsion, a flanged pipe subjected to pressure and axial force and a square plate with small central hole subjected to biaxial tension. The results obtained are compared with those in literatures, they are consistent with each other. Based on the resulting general analytical solution, rules governing the general effects of kinematic hardening behavior on the shakedown behavior of structure are clearly.

  20. Modeling copper precipitation hardening and embrittlement in a dilute Fe-0.3at.%Cu alloy under neutron irradiation

    Science.gov (United States)

    Bai, Xian-Ming; Ke, Huibin; Zhang, Yongfeng; Spencer, Benjamin W.

    2017-11-01

    Neutron irradiation in light water reactors can induce precipitation of nanometer sized Cu clusters in reactor pressure vessel steels. The Cu precipitates impede dislocation gliding, leading to an increase in yield strength (hardening) and an upward shift of ductile-to-brittle transition temperature (embrittlement). In this work, cluster dynamics modeling is used to model the entire Cu precipitation process (nucleation, growth, and coarsening) in a Fe-0.3at.%Cu alloy under neutron irradiation at 300°C based on the homogenous nucleation mechanism. The evolution of the Cu cluster number density and mean radius predicted by the modeling agrees well with experimental data reported in literature for the same alloy under the same irradiation conditions. The predicted precipitation kinetics is used as input for a dispersed barrier hardening model to correlate the microstructural evolution with the radiation hardening and embrittlement in this alloy. The predicted radiation hardening agrees well with the mechanical test results in the literature. Limitations of the model and areas for future improvement are also discussed in this work.

  1. DISTRIBUTED EXTERNAL SURFACE HARDENING OF CAR DESIGN BY WINDING

    Directory of Open Access Journals (Sweden)

    O. V. Fomin

    2017-04-01

    Full Text Available Purpose. The paper involves coverage of features and results of the research conducted by the authors to determine the feasibility and establishment of pre-stressed-strained state of freight cars by winding in order to improve their strength characteristics. It is also necessary to present the theoretical justification for the effectiveness of the application of this method for car designs and an appropriate example for the tank-car. Methodology. The conducted study is based on an analysis of known works on the subject, mathematical justification and computer modeling. At the calculations of rolling stock components contemporary conventional techniques were used. Findings. Authors found that the winding method for pre-stressed-strained state is effective and appropriate for use in the construction of railway rolling stock and, in particular freight cars. Freight car designs with the pre-stressed-strained state are characterized by a number of strength advantages, among which there is an improvement of the work on the perception of operational loads and resource conservation. Originality. For the first time it is proposed the improvement of bearing capacity of freight car constructions through the creation of its component in the directed stress-strained state. It is also for the first time proposed the use of distributed external surface hardening by the method of winding to create a pre-stress-strained state of structural components of freight cars. The methods for winding designs of freight cars and their implementation were considered. Practical value. The studies developed a number of technical solutions for improving the design of freight cars and tank-container, which has been patented. Corresponding solutions for the tank-car are partially presented. Practical implementation of such solutions will significantly improve the technical, economic and operational performances of car designs.

  2. Tensile properties and strain-hardening behavior of double-sided arc welded and friction stir welded AZ31B magnesium alloy

    International Nuclear Information System (INIS)

    Chowdhury, S.M.; Chen, D.L.; Bhole, S.D.; Cao, X.; Powidajko, E.; Weckman, D.C.; Zhou, Y.

    2010-01-01

    Microstructures, tensile properties and work hardening behavior of double-sided arc welded (DSAWed) and friction stir welded (FSWed) AZ31B-H24 magnesium alloy sheet were studied at different strain rates. While the yield strength was higher, both the ultimate tensile strength and ductility were lower in the FSWed samples than in the DSAWed samples due to welding defects present at the bottom surface in the FSWed samples. Strain-hardening exponents were evaluated using the Hollomon relationship, the Ludwik equation and a modified equation. After welding, the strain-hardening exponents were nearly twice that of the base metal. The DSAWed samples exhibited stronger strain-hardening capacity due to the larger grain size coupled with the divorced eutectic structure containing β-Mg 17 Al 12 particles in the fusion zone, compared to the FSWed samples and base metal. Kocks-Mecking type plots were used to show strain-hardening stages. Stage III hardening occurred after yielding in both the base metal and the welded samples. At lower strains a higher strain-hardening rate was observed in the base metal, but it decreased rapidly with increasing net flow stress. At higher strains the strain-hardening rate of the welded samples became higher, because the recrystallized grains in the FSWed and the larger re-solidified grains coupled with β particles in the DSAWed provided more space to accommodate dislocation multiplication during plastic deformation. The strain-rate sensitivity evaluated via Lindholm's approach was observed to be higher in the base metal than in the welded samples.

  3. 78 FR 42106 - Certain TV Programs, Literary Works for TV Production and Episode Guides Pertaining to Same...

    Science.gov (United States)

    2013-07-15

    ... INTERNATIONAL TRADE COMMISSION [Investigation No. 337-TA-886] Certain TV Programs, Literary Works for TV Production and Episode Guides Pertaining to Same; Institution of Investigation Pursuant to 19 U... of certain TV programs, literary works for TV production and episode guides pertaining to same by...

  4. 26 CFR 301.6511(d)-7 - Overpayment of income tax on account of work incentive program credit carryback.

    Science.gov (United States)

    2010-04-01

    ... or refund related to an overpayment of income tax attributable to a work incentive program (WIN... 26 Internal Revenue 18 2010-04-01 2010-04-01 false Overpayment of income tax on account of work incentive program credit carryback. 301.6511(d)-7 Section 301.6511(d)-7 Internal Revenue INTERNAL REVENUE...

  5. BladeRunners and Picasso Cafe: A Case Study Evaluation of Two Work-Based Training Programs for Disadvantaged Youth.

    Science.gov (United States)

    Currie, Sheila; Foley, Kelly; Schwartz, Saul; Taylor-Lewis, Musu

    In 1998, Canada's Social Research and Demonstration Corporation (SRDC) conducted case studies of two work-based training and skill development programs for street youth in Vancouver, British Columbia. The BladeRunners program places youth on construction sites while encouraging them to work toward an apprenticeship in the building trades. The…

  6. Chemical Dependency and Violence: Working with Dually Affected Families. A Cross-Training Program Manual for Counselors and Advocates.

    Science.gov (United States)

    Wright, Janet M.

    This manual is designed as a cross-training program guide for counselors working in the fields of woman abuse and chemical dependency. (A cross-training program is a system for one (or more) agency personnel to train each other in their respective areas of expertise.) Chapter 1 discusses the rationale and goals of a cross-training program; issues…

  7. Effectiveness of the Ticket to Work Program for Beneficiaries Who Are Blind or Have Low Vision: Comparisons with Other Beneficiaries

    Science.gov (United States)

    Capella-McDonnall, Michele

    2007-01-01

    The Ticket to Work (TTW) program is a federally funded program meant to assist persons who receive disability benefits from the Social Security Administration (SSA) in obtaining employment, with the ultimate goal of terminating SSA benefits and thereby providing a cost savings for the government. With its focus on employment, the TTW program would…

  8. The Danish national return-to-work program - aims, content, and design of the process and effect evaluation

    NARCIS (Netherlands)

    Aust, Birgit; Helverskov, Trine; Nielsen, Maj Britt D.; Bjorner, Jakob Bue; Rugulies, Reiner; Nielsen, Karina; Sorensen, Ole H.; Grundtvig, Gry; Andersen, Malene F.; Hansen, Jorgen V.; Buchardt, Helle L.; Nielsen, Lisbeth; Lund, Trine L.; Andersen, Irene; Andersen, Mogens H.; Clausen, Aksel S.; Heinesen, Eskil; Mortensen, Ole S.; Ektor-Andersen, John; Orbaek, Palle; Winzor, Glen; Bultmann, Ute; Poulsen, Otto M.

    The Danish national return-to-work (RTW) program aims to improve the management of municipal sickness benefit in Denmark. A study is currently ongoing to evaluate the RTW program. The purpose of this article is to describe the study protocol. The program includes 21 municipalities encompassing

  9. Preparing Science Teachers: Strong Emphasis on Science Content Course Work in a Master's Program in Education

    Science.gov (United States)

    Ajhar, Edward A.; Blackwell, E.; Quesada, D.

    2010-05-01

    In South Florida, science teacher preparation is often weak as a shortage of science teachers often prompts administrators to assign teachers to science classes just to cover the classroom needs. This results is poor preparation of students for college science course work, which, in turn, causes the next generation of science teachers to be even weaker than the first. This cycle must be broken in order to prepare better students in the sciences. At St. Thomas University in Miami Gardens, Florida, our School of Science has teamed with our Institute for Education to create a program to alleviate this problem: A Master of Science in Education with a Concentration in Earth/Space Science. The Master's program consists of 36 total credits. Half the curriculum consists of traditional educational foundation and instructional leadership courses while the other half is focused on Earth and Space Science content courses. The content area of 18 credits also provides a separate certificate program. Although traditional high school science education places a heavy emphasis on Earth Science, this program expands that emphasis to include the broader context of astronomy, astrophysics, astrobiology, planetary science, and the practice and philosophy of science. From this contextual basis the teacher is better prepared to educate and motivate middle and high school students in all areas of the physical sciences. Because hands-on experience is especially valuable to educators, our program uses materials and equipment including small optical telescopes (Galileoscopes), several 8-in and 14-in Celestron and Meade reflectors, and a Small Radio Telescope installed on site. (Partial funding provided by the US Department of Education through Minority Science and Engineering Improvement Program grant P120A050062.)

  10. The Effect of Programmed Physical Exercise to Attention and Working Memory Score in Medical Students

    Directory of Open Access Journals (Sweden)

    Kevin Fachri Muhammad

    2015-06-01

    Full Text Available Background: Attention and working memory are two cognitive domain crucial for activities of daily living. Physical exercise increases the level of BDNF, IGF-1, and VEGF which contributes in attention and working memory processes.This study was conducted to analyze improvement of attention and working memory after programmed physical exercise of Pendidikan Dasar XXI Atlas Medical Pioneer (Pendas XXI AMP. Methods: An analytic observational study was conducted on 47 students from Faculty of Medicine, Universitas Padjadjaran during September-November 2012. Attention was assessed using digit span backward test, stroop test, visual search task, and trail making test. Working memory was assessed using digit span forward test and digit symbol test. Assessment was done on the 11th and 19th week of Pendas XXI AMP. Data distribution was tested first using a test of normality, and then analyzed using T-Dependent Test and Wilcoxon Test Results: Significant improvement was noted for attention in males based on working time for stroop test (26.50±5.66 to 22.03±3.78 seconds, working memory in males based on digit symbol test score (43.96±6.14 to 53.36±5.26 points, attention in females based on reaction time of visual search task for target absent (0.92±0.07 to 0.87±0.07 seconds, and working memory in females based on digit span forward score (5.42±1.30 to 6.63±1.07 points and digit symbol test score (42.47±5.95 to 53.84±5.33 points. Conclusions: Exercise in Pendas XXI AMP improves attention and working memory for college students in Faculty of Medicine Universitas Padjadjaran.

  11. Influence of coolant motion on structure of hardened steel element

    Directory of Open Access Journals (Sweden)

    A. Kulawik

    2008-08-01

    Full Text Available Presented paper is focused on volumetric hardening process using liquid low melting point metal as a coolant. Effect of convective motion of the coolant on material structure after hardening is investigated. Comparison with results obtained for model neglecting motion of liquid is executed. Mathematical and numerical model based on Finite Element Metod is described. Characteristic Based Split (CBS method is used to uncouple velocities and pressure and finally to solve Navier-Stokes equation. Petrov-Galerkin formulation is employed to stabilize convective term in heat transport equation. Phase transformations model is created on the basis of Johnson-Mehl and Avrami laws. Continuous cooling diagram (CTPc for C45 steel is exploited in presented model of phase transformations. Temporary temperatures, phases participation, thermal and structural strains in hardening element and coolant velocities are shown and discussed.

  12. Investigation of magnesium oxychloride cement at the initial hardening stage

    Directory of Open Access Journals (Sweden)

    Averina Galina

    2018-01-01

    Full Text Available The paper investigates the process of variation of magnesium oxychloride cement deformations at the initial hardening stage depending on the activity of magnesium oxide powder which is determined by the parameters of the source material burning. Investigation is focused on magnesium cements obtained from pure magnesium hydroxide. Source materials were burnt at various temperatures with the purpose to obtain magnesium oxide powder with different activity. Regular content of hydrated phases was determined in hardened magnesium cement prepared on the basis of binders with different activity. The study reveals the influence of magnesium oxide powder activity on the process of deformation occurrence in hardened magnesium cement and its tendency to crack formation.

  13. Effect of ethephon on hardening of Pachystroma longifolium seedlings

    Directory of Open Access Journals (Sweden)

    João Alexandre Lopes Dranski

    2013-06-01

    Full Text Available Immediately after planting, tree seedlings face adverse environmental and biotic stresses that must be overcome to ensure survival and to yield a desirable growth. Hardening practices in the nursery may help improve seedling stress resistance through reduction of aboveground plant tissues and increased root volume and biomass. We conducted an assay to quantify changes in the morphogenesis following application of ethephon on seedlings of Pachystroma longifolium (Ness I. M. Johnst.during hardening. The results showed no effect of the ethephon treatments on the number of leaves but a reduction of up to 50% in seedling height increment, and an increase in stem diameter increment of up to 44% with the 600 mg L-1 ethephon treatment, which consequently altered seedling Dickson Quality Index. Our results indicate that ethephon may help to promote desired morphological changes that occur during seedling hardening in nurseries.

  14. Branching structure and strain hardening of branched metallocene polyethylenes

    International Nuclear Information System (INIS)

    Torres, Enrique; Li, Si-Wan; Costeux, Stéphane; Dealy, John M.

    2015-01-01

    There have been a number of studies of a series of branched metallocene polyethylenes (BMPs) made in a solution, continuous stirred tank reactor (CSTR) polymerization. The materials studied vary in branching level in a systematic way, and the most highly branched members of the series exhibit mild strain hardening. An outstanding question is which types of branched molecules are responsible for strain hardening in extension. This question is explored here by use of polymerization and rheological models along with new data on the extensional flow behavior of the most highly branched members of the set. After reviewing all that is known about the effects of various branching structures in homogeneous polymers and comparing this with the structures predicted to be present in BMPs, it is concluded that in spite of their very low concentration, treelike molecules with branch-on-branch structure provide a large number of deeply buried inner segments that are essential for strain hardening in these polymers

  15. Branching structure and strain hardening of branched metallocene polyethylenes

    Energy Technology Data Exchange (ETDEWEB)

    Torres, Enrique; Li, Si-Wan; Costeux, Stéphane; Dealy, John M., E-mail: john.dealy@mcgill.ca [Department of Chemical Engineering, McGill University, Montreal, Quebec H3A 0C4 (Canada)

    2015-09-15

    There have been a number of studies of a series of branched metallocene polyethylenes (BMPs) made in a solution, continuous stirred tank reactor (CSTR) polymerization. The materials studied vary in branching level in a systematic way, and the most highly branched members of the series exhibit mild strain hardening. An outstanding question is which types of branched molecules are responsible for strain hardening in extension. This question is explored here by use of polymerization and rheological models along with new data on the extensional flow behavior of the most highly branched members of the set. After reviewing all that is known about the effects of various branching structures in homogeneous polymers and comparing this with the structures predicted to be present in BMPs, it is concluded that in spite of their very low concentration, treelike molecules with branch-on-branch structure provide a large number of deeply buried inner segments that are essential for strain hardening in these polymers.

  16. Nonlinear kinematic hardening under non-proportional loading

    International Nuclear Information System (INIS)

    Ottosen, N.S.

    1979-07-01

    Within the framework of conventional plasticity theory, it is first determined under which conditions Melan-Prager's and Ziegler's kinematic hardening rules result in identical material behaviour. Next, assuming initial isotropy and adopting the von Mises yield criterion, a nonlinear kinematic hardening function is proposed for prediction of metal behaviour. The model assumes that hardening at a specific stress point depends on the direction of the new incremental loading. Hereby a realistic response is obtained for general reversed loading, and a smooth behaviour is assured, even when loading deviates more and more from proportional loading and ultimately results in reversed loading. The predictions of the proposed model for non-proportional loading under plane stress conditions are compared with those of the classical linear kinematic model, the isotropic model and with published experimental data. Finally, the limitations of the proposaed model are discussed. (author)

  17. Interactive effects of work psychosocial factors on participation in workplace wellness programs.

    Science.gov (United States)

    Sangachin, Mahboobeh Ghesmaty; Cavuoto, Lora A

    2018-01-01

    This study explored concurrent effects of six work psychosocial factors on current participation and the self-reported likelihood of future participation in workplace wellness programs using a cross-sectional survey, an ad hoc focus group, and structured interviews. Classification and regression tree analysis was used to analyze survey responses from 343 employees (194 nonparticipants, 95 participants, and 54 engaged participants). A thematic analysis of focus group ( n = 7) and interview ( n = 5) narratives was also undertaken. In combination with high work control, high superior support was associated with an engaged participant profile. Job demand was the third important variable with low and very high levels associated with participation. With regard to high likelihood of future participation, among respondents with age older than 50, high predictability of occupational activities and control were identified as a significant factor, and among others, high superior support and control. The analysis of narratives revealed peer relations and flexible working hours to be positively linked to participation and general job stress was identified as having a bidirectional relationship. Employees stated that stress led them to take advantage of these programs as a source of relief and that their availability/participation has contributed to lowering their stress. These findings inform practitioners about the importance of addressing poor psychosocial factors as a participation barrier and having a holistic approach to employee well-being.

  18. Kinematic Hardening: Characterization, Modeling and Impact on Springback Prediction

    International Nuclear Information System (INIS)

    Alves, J. L.; Bouvier, S.; Jomaa, M.; Billardon, R.; Oliveira, M. C.; Menezes, L. F.

    2007-01-01

    The constitutive modeling of the materials' mechanical behavior, usually carried out using a phenomenological constitutive model, i.e., a yield criterion associated to the isotropic and kinematic hardening laws, is of paramount importance in the FEM simulation of the sheet metal forming processes, as well as in the springback prediction. Among others, the kinematic behavior of the yield surface plays an essential role, since it is indispensable to describe the Bauschinger effect, i.e., the materials' answer to the multiple tension-compression cycles to which material points are submitted during the forming process. Several laws are usually used to model and describe the kinematic hardening, namely: a) the Prager's law, which describes a linear evolution of the kinematic hardening with the plastic strain rate tensor b) the Frederick-Armstrong non-linear kinematic hardening, basically a non-linear law with saturation; and c) a more advanced physically-based law, similar to the previous one but sensitive to the strain path changes. In the present paper a mixed kinematic hardening law (linear + non-linear behavior) is proposed and its implementation into a static fully-implicit FE code is described. The material parameters identification for sheet metals using different strategies, and the classical Bauschinger loading tests (i.e. in-plane forward and reverse monotonic loading), are addressed, and their impact on springback prediction evaluated. Some numerical results concerning the springback prediction of the Numisheet'05 Benchmark no. 3 are briefly presented to emphasize the importance of a correct modeling and identification of the kinematic hardening behavior

  19. Work out by Walking: A Pilot Exercise Program for Individuals With Schizophrenia Spectrum Disorders.

    Science.gov (United States)

    Browne, Julia; Penn, David L; Battaglini, Claudio L; Ludwig, Kelsey

    2016-09-01

    The health benefits of exercise are well documented, yet annual health care costs related to physical inactivity are well within the billions. Furthermore, individuals with schizophrenia spectrum disorders (SSDs) are more likely to lead sedentary lives, exercise less than the general population, and die prematurely from preventable causes. Previous research examining the effects of exercise on individuals with SSDs has been encouraging yet limited in creating accessible and sustainable interventions. The current pilot study developed and evaluated the impact of Work out by Walking (WOW), a multicomponent group walking intervention on the health of 16 individuals with SSDs. Results indicated improvements in indicators of physical health, activity level, social support, and mental health and a high level of program satisfaction. Future research should examine multicomponent group walking programs for individuals with SSDs in larger samples and with the inclusion of a comparison condition.

  20. Work-Experience and Work-Study Programs for Students with Special Needs: Quality Indicators of Transition Services.

    Science.gov (United States)

    Wisniewski, Lech A.; And Others

    1991-01-01

    This article proposes a continuum of employment training options for students with special needs and identifies program quality indicators in the areas of assessment and the Individual Education Plan; the employment training program; community-based settings; provisions for on-site training and evaluation; and interagency cooperation. (DB)

  1. Effects of a work-based critical reflection program for novice nurses.

    Science.gov (United States)

    Kim, Yeon Hee; Min, Ja; Kim, Soon Hee; Shin, Sujin

    2018-02-27

    Critical reflection is effective in improving students' communication abilities and confidence. The aim of this study was to evaluate the effectiveness of a work-based critical reflection program to enhance novice nurses' clinical critical-thinking abilities, communication competency, and job performance. The present study used a quasi-experimental design. From October 2014 to August 2015, we collected data from 44 novice nurses working in an advanced general hospital in S city in Korea. Nurses in the experimental group participated in a critical reflection program for six months. Outcome variables were clinical critical-thinking skills, communication abilities, and job performance. A non-parametric Mann-Whitney U-test and a Wilcoxon rank sum test were selected to evaluate differences in mean ranks and to assess the null hypothesis that the medians were equal across the groups. The results showed that the clinical critical-thinking skills of those in the experimental group improved significantly (p = 0.003). The differences in mean ranks of communication ability between two groups was significantly statistically different (p = 0.028). Job performance improved significantly in both the experimental group and the control group, so there was no statistical difference (p = 0.294). We therefore suggest that a critical reflection program be considered an essential tool for improving critical thinking and communication abilities among novice nurses who need to adapt to the clinical environment as quickly as possible. Further, we suggest conducting research into critical reflection programs among larger and more diverse samples.

  2. The application and processing of paints hardened by electron beams

    International Nuclear Information System (INIS)

    Anon.

    1984-01-01

    Electron beam hardening is a process for changing liquid surface coatings of different thicknesses by irradiation with electrons of high energy into solid, hard, elastic films. In contrast to the UV process, one can harden pigmented paints with electron beams. An electron accelerator, which remits free electrons is used as the energy source for starting the chemical reaction in the coating material. In order to irradiate flat parts, which were coated with liquid paint by rolling, pouring or spraying, equally with electrons, one must produce an 'electron curtain', similar to that in a paint pouring machine. (orig./PW) [de

  3. Why semiconductors must be hardened when used in space

    International Nuclear Information System (INIS)

    Winokur, P.S.

    2000-01-01

    The natural space radiation environment presents a great challenge to present and future satellite systems with significant assets in space. Defining requirements for such systems demands knowledge about the space radiation environment and its effects on electronics and optoelectronics technologies, as well as suitable risk assessment of the uncertainties involved. For mission of high radiation levels, radiation-hardened integrated circuits will be required to preform critical mission functions. The most successful systems in space will be those that are best able to blend standard commercial electronics with custom radiation-hardened electronics in a mix that is suitable for the system of interest

  4. Radiation Hardened 10BASE-T Ethernet Physical Layer (PHY)

    Science.gov (United States)

    Lin, Michael R. (Inventor); Petrick, David J. (Inventor); Ballou, Kevin M. (Inventor); Espinosa, Daniel C. (Inventor); James, Edward F. (Inventor); Kliesner, Matthew A. (Inventor)

    2017-01-01

    Embodiments may provide a radiation hardened 10BASE-T Ethernet interface circuit suitable for space flight and in compliance with the IEEE 802.3 standard for Ethernet. The various embodiments may provide a 10BASE-T Ethernet interface circuit, comprising a field programmable gate array (FPGA), a transmitter circuit connected to the FPGA, a receiver circuit connected to the FPGA, and a transformer connected to the transmitter circuit and the receiver circuit. In the various embodiments, the FPGA, transmitter circuit, receiver circuit, and transformer may be radiation hardened.

  5. Aspect-oriented security hardening of UML design models

    CERN Document Server

    Mouheb, Djedjiga; Pourzandi, Makan; Wang, Lingyu; Nouh, Mariam; Ziarati, Raha; Alhadidi, Dima; Talhi, Chamseddine; Lima, Vitor

    2015-01-01

    This book comprehensively presents a novel approach to the systematic security hardening of software design models expressed in the standard UML language. It combines model-driven engineering and the aspect-oriented paradigm to integrate security practices into the early phases of the software development process. To this end, a UML profile has been developed for the specification of security hardening aspects on UML diagrams. In addition, a weaving framework, with the underlying theoretical foundations, has been designed for the systematic injection of security aspects into UML models. The

  6. Microstructure and properties of cast iron after laser surface hardening

    Directory of Open Access Journals (Sweden)

    Stanislav

    2013-12-01

    Full Text Available Laser surface hardening of cast iron is not trivial due to the material’s heterogeneity and coarse-grained microstructure, particularly in massive castings. Despite that, hardening of heavy moulds for automotive industry is in high demand. The present paper summarises the findings collected over several years of study of materials structure and surface properties. Phase transformations in the vicinity of graphite are described using examples from production of body parts in automotive industry. The description relates to formation of martensite and carbide-based phases, which leads to hardness values above 65 HRC and to excellent abrasion resistance.

  7. Effect of aluminizing on hardenability of steel (S45C)

    Science.gov (United States)

    Prayitno, D.; Sugiarto, R.

    2018-01-01

    The objective of research is to know the effect of aluminizing on hardenability of steel (S45C). The research methodologies were as follows. The Steels (S45C) were machined into the Jominy test samples. Next the samples were preheating at 700 ° C for 30 minutes and then the samples were dipped into the molten of aluminium for 3 minutes as a hot dip aluminizng method. The aluminium molten was 700 ° C. Then the samples were cooled into room temperatures. Finally the samples were into the jominy tested. The results show that the aluminizing (include the preheating process) increases the hardenability of steel (S45C).

  8. Structure of hardened alloys of Sr-Rh system

    International Nuclear Information System (INIS)

    Dobromyslov, A.V.; Taluth, N.I.

    1997-01-01

    Methods of X-ray diffraction analysis, optical metallography, transmission electron microscopy and hardness measurement were applied to study the structure of hardened zirconium-rhodium system alloys with rhodium contents up to 4.5 at.%. It is shown that in hardening alloys with rhodium concentration lower 2.2 at.% the eutectoid decomposition takes place and bainite-like structure is formed. A metastable ω-phase is formed in alloys with rhodium concentration equal to 2.65 at.% and above. The formation of ω-phase suppresses the process of eutectoid decomposition

  9. Changes in hardness of magnesium alloys due to precipitation hardening

    Directory of Open Access Journals (Sweden)

    Tatiana Oršulová

    2018-04-01

    Full Text Available This paper deals with the evaluation of changes in hardness of magnesium alloys during precipitation hardening that are nowadays widely used in different fields of industry. It focuses exactly on AZ31, AZ61 and AZ91 alloys. Observing material hardness changes serves as an effective tool for determining precipitation hardening parameters, such as temperature and time. Brinell hardness measurement was chosen based on experimental needs. There was also necessary to make chemical composition analysis and to observe the microstructures of tested materials. The obtained results are presented and discussed in this paper.

  10. Thermal stress ratcheting analysis of a time-hardening structure

    International Nuclear Information System (INIS)

    Hada, Kazuhiko

    1999-01-01

    Thermal stress ratcheting and shakedown is analyzed for a time-hardening structure: the yield stress increases as time goes on under exposure to neutron irradiation or thermal aging. New three modes of ratcheting and shakedown are identified as transition to other deformation modes. Stress regimes and thermal ratchet strains are formulated as a function of time-increasing yield stress. Moreover, a new model of trouble occurrence frequency as a modification to a bath-tube curve is proposed for calculating a time period of a thermal cycle. Application of the proposed formulation tells us a benefit of taking into account the time hardening due to neutron irradiation. (author)

  11. Work plan for the Oak Ridge National Laboratory groundwater program: Continuous groundwater collection

    International Nuclear Information System (INIS)

    1995-08-01

    The continuous collection of groundwater data is a basic and necessary part of Lockeheed Martin Energy Systems' ORNL Environmental Restoration Area-Wide Groundwater Program. Continuous groundwater data consist primarily of continually recorded groundwater levels, and in some instances, specific conductivity, pH, and/or temperature measurements. These data will be collected throughout the ORNL site. This Work Plan (WP) addresses technical objectives, equipment requirements, procedures, documentation requirements, and technical instructions for the acquisition of the continuous groundwater data. Intent of this WP is to provide an approved document that meets all the necessary requirements while retaining the flexibility necessary to effectively address ORNL's groundwater problems

  12. A tool for Load Modeling in Induction Hardening Equipment Driven by Power Semiconductor Systems

    International Nuclear Information System (INIS)

    Suarez Antola, R.; Suarez Bagnasco, D.

    2006-01-01

    Kelvin effect (Skin effect) is used in surface hardening produced by induction heating of gears, camforms, camshafts and other work pieces of fairly complex geometries.The induction heating equipment for surface hardening of metals and alloys (using LF or medium frequencies in the jargon of induction heating) is composed by a coil or coil assembly and a power semiconductor driving system up to 50kHz. The load seen by the driving system is equivalent to a transformer. The primary corresponds to the excitation coil or coil assembly, and the work piece corresponds to a short-circuited secondary. To asses the electrical load it is necessary to determine the variations in skin depth from place to place due to local curvature effects in the work piece, and its variations in space and time due to variations in conductivity and magnetic properties coupled with thermal effects. In these and others technical applications of Kelvin effect it is often necessary to be able to relate local skin depths with local curvatures of the surface of electrically conductive bodies.The purpose of this paper is twofold. First, derive a closed form analytical formula that relates the local skin depth with the local mean curvature and the well known skin depth for a flat conductive body. The limits of applicability of this formula are discussed. The predicted skin depths are compared with available experimental results obtained in the framework of surface hardening processes. Second, apply the above mentioned formula to describe the electrical load of the induction heating equipment in the conditions used for surface hardening. In the choice or design of an induction heating system the parameters of the intended process (depth of Kelvin effect, temperatures to be reached and duration of the heating process, amongst others) put restrictions over the coils and the power driving system. To determine the best shape and size of induction coils or coil assemblies, the complex thermal and

  13. Working program for deep borehole investigations. HDB-6,7,8, borehole

    International Nuclear Information System (INIS)

    Hama, Katsuhiro; Takahashi, Kazuharu; Ishii, Eiichi; Takeuchi, Ryuji; Sasaki, Manabu; Kunimaru, Takanori; Eki, Nobuhiro; Matsui, Hiroya

    2003-08-01

    optimized program for deep borehole (HDB-6, 7, 8) investigations has been drawn-up. This program addresses the general issues and provides input to the subsequent investigation programs and design for the shaft and experimental drifts. This document mainly describes the planned working program for the HDB-6, 7, 8 borehole investigations including associated laboratory programs during and after drilling. The working program is divided into the following investigation fields: borehole drilling geology, geophysics, hydrogeology, hydrochemistry, rock mechanics and long-term monitoring. Post-HDB borehole investigations; a VSP (Vertical Seismic Profiling) survey are planned in the surface-based investigations phase. (author)

  14. Canine Supply for Physical Security: An Analysis of the Royal Australian Air Force Military Working Dog Program

    Science.gov (United States)

    2016-03-01

    PHYSICAL SECURITY: AN ANALYSIS OF THE ROYAL AUSTRALIAN AIR FORCE MILITARY WORKING DOG PROGRAM by Mark W. Powell March 2016 Thesis...AN ANALYSIS OF THE ROYAL AUSTRALIAN AIR FORCE MILITARY WORKING DOG PROGRAM 5. FUNDING NUMBERS 6. AUTHOR(S) Mark W. Powell 7. PERFORMING...increased demand on its physical security elements. Its military working dog (MWD) workforce is required to meet an inventory of 204 by end of year 2023 as

  15. Correctional officers' perceptions of a solution-focused training program: potential implications for working with offenders.

    Science.gov (United States)

    Pan, Peter Jen Der; Deng, Liang-Yu F; Chang, Shona Shih Hua; Jiang, Karen Jye-Ru

    2011-09-01

    The purpose of this exploratory study was to explore correctional officers' perceptions and experiences during a solution-focused training program and to initiate development of a modified pattern for correctional officers to use in jails. The study uses grounded theory procedures combined with a follow-up survey. The findings identified six emergent themes: obstacles to doing counseling work in prisons, offenders' amenability to change, correctional officers' self-image, advantages of a solution-focused approach (SFA), potential advantages of applying SFA to offenders, and the need for the consolidation of learning and transformation. Participants perceived the use of solution-focused techniques as appropriate, important, functional, and of only moderate difficulty in interacting with offenders. Finally, a modified pattern was developed for officers to use when working with offenders in jails. Suggestions and recommendations are made for correctional interventions and future studies.

  16. Working Together to Connect Care: a metropolitan tertiary emergency department and community care program.

    Science.gov (United States)

    Harcourt, Debra; McDonald, Clancy; Cartlidge-Gann, Leonie; Burke, John

    2017-03-02

    Objective Frequent attendance by people to an emergency department (ED) is a global concern. A collaborative partnership between an ED and the primary and community healthcare sectors has the potential to improve care for the person who frequently attends the ED. The aims of the Working Together to Connect Care program are to decrease the number of presentations by providing focused community support and to integrate all healthcare services with the goal of achieving positive, patient-centred and directed outcomes. Methods A retrospective analysis of ED data for 2014 and 2015 was used to ascertain the characteristics of the potential program cohort. The definition used to identify a 'frequent attendee' was more than four presentations to an ED in 1 month. This analysis was used to develop the processes now known as the Working Together to Connect Care program. This program includes participant identification by applying the definition, flagging of potential participants in the ED IT system, case review and referral to community services by ED staff, case conferencing facilitated within the ED and individualised, patient centred case management provided by government and non-government community services. Results Two months after the date of commencement of the Working Together to Connect Care program there are 31 active participants in the program: 10 are on the Mental Health pathway, and one is on the No Consent pathway. On average there are three people recruited to the program every week. The establishment of a new program for supporting frequent attendees of an ED has had its challenges. Identifying systems that support people in their community has been an early positive outcome of this project. Conclusion It is expected that data regarding the number of ED presentations, potential fiscal savings and client outcomes will be available in 2017. What is known about the topic? Frequent attendance at EDs is a global issue and although the number of 'super users' is

  17. An experimental study on the influence of scatter and beam hardening in x-ray CT for dimensional metrology

    International Nuclear Information System (INIS)

    Lifton, J J; McBride, J W; Malcolm, A A

    2016-01-01

    Scattered radiation and beam hardening introduce artefacts that degrade the quality of data in x-ray computed tomography (CT). It is unclear how these artefacts influence dimensional measurements evaluated from CT data. Understanding and quantifying the influence of these artefacts on dimensional measurements is required to evaluate the uncertainty of CT-based dimensional measurements. In this work the influence of scatter and beam hardening on dimensional measurements is investigated using the beam stop array scatter correction method and spectrum pre-filtration for the measurement of an object with internal and external cylindrical dimensional features. Scatter and beam hardening are found to influence dimensional measurements when evaluated using the ISO50 surface determination method. On the other hand, a gradient-based surface determination method is found to be robust to the influence of artefacts and leads to more accurate dimensional measurements than those evaluated using the ISO50 method. In addition to these observations the GUM method for evaluating standard measurement uncertainties is applied and the standard measurement uncertainty due to scatter and beam hardening is estimated. (paper)

  18. Implementing a collaborative return-to-work program: Lessons from a qualitative study in a large Canadian healthcare organization.

    Science.gov (United States)

    Skivington, Kathryn; Lifshen, Marni; Mustard, Cameron

    2016-11-22

    Comprehensive workplace return-to-work policies, applied with consistency, can reduce length of time out of work and the risk of long-term disability. This paper reports on the findings from a qualitative study exploring managers' and return-to-work-coordinators' views on the implementation of their organization's new return-to-work program. To provide practical guidance to organizations in designing and implementing return-to-work programs for their employees. Semi-structured qualitative interviews were undertaken with 20 managers and 10 return-to-work co-ordinators to describe participants' perspectives on the progress of program implementation in the first 18 months of adoption. The study was based in a large healthcare organization in Ontario, Canada. Thematic analysis of the data was conducted. We identified tensions evident in the early implementation phase of the organization's return-to-work program. These tensions were attributed to uncertainties concerning roles and responsibilities and to circumstances where objectives or principles appeared to be in conflict. The implementation of a comprehensive and collaborative return-to-work program is a complex challenge. The findings described in this paper may provide helpful guidance for organizations embarking on the development and implementation of a return-to-work program.

  19. Health in All Social Work Programs: Findings From a US National Analysis

    Science.gov (United States)

    Wachman, Madeline K.; Marshall, Jamie W.; Backman, Allison R.; Harrington, Calla B.; Schultz, Neena S.; Ouimet, Kaitlyn J.

    2017-01-01

    Objectives. To establish a baseline of health content in 4 domains of US social work education—baccalaureate, master’s, doctoral, and continuing education programs—and to introduce the Social Work Health Impact Model, illustrating social work’s multifaceted health services, from clinical to wide-lens population health approaches. Methods. We analyzed US social work programs’ Web site content to determine amount and types of health content in mission statements, courses, and specializations. Coding criterion determined if content was (1) health or health-related (HHR) and (2) had wide-lens health (WLH) emphasis. A second iteration categorized HHR and WLH courses into health topics. Results. We reviewed 4831 courses. We found broad HHR content in baccalaureate, master’s, and continuing education curricula; doctoral programs had limited health content. We identified minimal WLH content across all domains. Topical analysis indicated that more than 50% of courses concentrated on 3 areas: mental and behavioral health, abuse and violence, and substance use and addictions. Conclusions. As a core health profession, social work must strengthen its health and wide-lens content to better prepare graduates for integrated practice and collaboration in the changing health environment. PMID:29236538

  20. Fresh and hardened properties of binary blend high strength self compacting concrete

    Directory of Open Access Journals (Sweden)

    S.S. Vivek

    2017-06-01

    Full Text Available Self compacting concrete (SCC made a remarkable impact on the concrete construction industry because of its innovative nature. Assessment of optimal ratio between chemical and mineral admixtures plays a vital role in developing SCC. In the present work three different mineral admixtures were used as partial substitute in different proportions to cement to produce SCC with a characteristic compressive strength of 60 MPa. All the three types of SCC were investigated for its fresh and hardened properties. From the results, 50% GGBFS, 10% SF and 20% MK were found to the optimum values as partial substitute to cement.