Journal articles: 'Work hardening program'

1

Johnson, Leslie Stratton, Gail Archer-Heese, Deanne L. Caron-Powles, and Tracey M. Dowson. "Work hardening: Outdated fad or effective intervention?" WORK: A Journal of Prevention, Assessment & Rehabilitation 16, no. 3 (2001): 235–43. https://doi.org/10.3233/wor-2001-00156.

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{\it Objectives}: The purpose of this outcome measurement study was to determine the effectiveness of a work hardening program as measured by the participants' work status at three months after program completion. Predictors of successful return to work were explored. {\it Study design}: The sequential case series design was employed, and data were gathered at three points: the initial work hardening assessment, the discharge assessment, and three months post-discharge from the work hardening program. Seventy-nine participants were included. {\it Results}: Eighty-two percent (82%) of the clients who completed a work hardening program reported that they were working in some capacity three months after program completion. They listed their employment status in 5 sub-categories. Significant predictors of employment included ``single'' marital status, lower perceived disability scores at program entry, reduction in reported pain during program duration, and funding source. {\it Conclusion}: Work hardening remains an effective treatment strategy which promotes successful return to the workplace. Ongoing analyses of these programs is imperative.

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Sang, Lau Shun, and Li Ping Ying Eria. "Outcome evaluation of work hardening program for manual workers with work-related back injury." WORK: A Journal of Prevention, Assessment & Rehabilitation 25, no. 4 (2005): 297–305. https://doi.org/10.3233/wor-2005-00467.

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Objective: The purpose of this study was to investigate the effectiveness of a 12-week work hardening program designed for back injured workers. Study design: In this study, 32 subjects were recruited. Pre- and post-assessment results were used to measure the program effectiveness. The intensity of the work hardening program was based on the overloading training principle. Subjects were contacted by phone three months after the program completion for their work status. Result: The findings of this study suggested that there was a significant difference in the subjects' physical demand characteristic level before and after the work hardening program. Seventy-five percent of the subjects who completed the work hardening program were able to resume employment. Conclusion: The rate of returning to work for back injured workers in this study was comparable to that of other studies. Thus, this study suggests that the overloading principle should be used in designing a work hardening program to improve clients' physical function.

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Nisarga, N. Chilakwad, and Rais A. Rizvi. Syed. "EFFECTIVENESS OF WORK HARDENING PROGRAM IN BANKERS HAVING WORK-RELATED CHRONIC NECK PAIN IN BANGALORE." VIMS Journal of Physical Therapy 1, no. 2 (2019): 79–85. https://doi.org/10.5281/zenodo.3753857.

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Backgroundand Objectives: Disorders caused due to working patterns or work related stresses are called occupa-tional disorders.Work related neck disorders are common problems in office workers,especially among those who are intensive computer users.Banking occupation requires a lot of stereotyped movements of the arms, hands and fin-gers,and repetitive occupational tasks with short cycle times have become more and more frequent in modern tech-nology as seen in this type of occupation with many of them associated with increased rates of chronic neck pain. Work place rehabilitation is necessary for work related to chronic neck pain in bankers.The objective of the study was to evaluate the effectiveness of the Work hardening program along with Conservative treatment versus Conservative treatment alone in bankers having Chronic neck pain. Methods:60 bankers having Chronic neck pain were randomly allocated in two groups.Group A received Conservative treatment alone and Group B received a Work hardening program along with Conservative treatment.The outcome was assessed in terms of Neck Disability Scale (NDI) scores and Numeric Pain rating Scale (NPRS) scores pre interven-tion and post intervention. Results:Both the interventions of conservative treatment and conservative treatment with a work hardening pro-gram were individually effective.But,the subjects treated with a conservative with work hardening program was sig-nificantly effective than conservative alone. Interpretation and Conclusion:The present study concludes that both treatment protocols were effective in reduc-ing Chronic neck pain.Further it was also noticed that Group B was more effective in improving neck disability and in reducing pain than Group A.Thus applying for the treatment protocol Work hardening program along with Conserva-tive treatment was better than Conservative treatment applied alone.

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Ricke, Stacey A., Paul J. Chara, and Mary M. Johnson. "Work Hardening: Evidence for Success of a Program." Psychological Reports 77, no. 3_suppl (1995): 1077–78. http://dx.doi.org/10.2466/pr0.1995.77.3f.1077.

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The effectiveness of a work hardening program in facilitating gains in physical strength and return to work in 40 chronic low back-pain clients was assessed. Statistically significant gains in physical strength were found. Also, 27 of the 32 clients reached by follow-up telephone calls returned to work full time.

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Voaklander, Donald C., A. Paul Beaulne, and Rene A. Lessard. "Factors related to outcome following a work hardening program." Journal of Occupational Rehabilitation 5, no. 2 (1995): 71–85. http://dx.doi.org/10.1007/bf02109911.

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Ambrosius, Frank M., Barbara K. Rounds, Peter B. Herkner, Mark A. Dekraker, and Steven R. Bartz. "Reactivation of Injured Workers Involved in a Work-Hardening Program." Work 4, no. 1 (1994): 28–34. http://dx.doi.org/10.3233/wor-1994-4105.

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Rytökoski, Ulla, Aaro Rissanen, and Seija Talo. "Progressive work hardening program for patients with chronic low back pain." International Journal of Rehabilitation Research 12, no. 3 (1989): 347. http://dx.doi.org/10.1097/00004356-198909000-00023.

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Cooper, J. E., R. Tate, and A. Yassi. "Work hardening in an early return to work program for nurses with back injury." Work 8, no. 2 (1997): 149–56. http://dx.doi.org/10.3233/wor-1997-8205.

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Christine Scully-Palmer. "Outcome study: An industrial rehabilitation program." WORK: A Journal of Prevention, Assessment & Rehabilitation 15, no. 1 (2000): 21–23. https://doi.org/10.3233/wor-2000-00100.

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A review of work hardening outcome research reveals a wide range of return to work statistics between 50% are forcing therapy services to objectively quantify their successes to ensure a future in health care. Work Venture has been maintaining program outcome statistics since 1994. In this report, 1997 and 1998 return to work statistics are documented and compared to multiple programs. Work Venture's average annual return to gainful employment percentages for 1997 are 61.2% at 6 months, and in 1998, 76.8% discharge. Many factors are involved in successful return to work with workers compensation claims. Due to these factors it is difficult to compare one program's results with another. It is recommended that a uniform method of collecting and presenting data be developed to ensure valid comparison.

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Greenberg, Susan N., and Raymond P. Bello. "The Work Hardening Program and Subsequent Return to Work of a Client With Low Back Pain." Journal of Orthopaedic & Sports Physical Therapy 24, no. 1 (1996): 37–45. http://dx.doi.org/10.2519/jospt.1996.24.1.37.

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11

Robert, Jacalyn J., Richard W. Blide, Kevin McWhorter, and Chris Coursey. "The Effects of a Work Hardening Program on Cardiovascular Fitness and Muscular Strength." Spine 20, no. 10 (1995): 1187–93. http://dx.doi.org/10.1097/00007632-199505150-00014.

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12

Moffroid, Mary T., Diana Aja, Krystal Laflin, Larry D. Haugh, and Sharon Henry. "Efficacy of a Part-Time Work Hardening Program for Persons with Low-Back Pain." Work 3, no. 3 (1993): 14–20. http://dx.doi.org/10.3233/wor-1993-3304.

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Baker, Patrick, Glenn Goodman, Beth Ekelman, and Bette Bonder. "The effectiveness of a comprehensive work hardening program as measured by lifting capacity, pain scales, and depression scores." WORK: A Journal of Prevention, Assessment & Rehabilitation 24, no. 1 (2005): 21–31. https://doi.org/10.3233/wor-2005-00384.

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Objective: The purpose of this pilot study was to examine the effectiveness of a four-week work rehabilitation program. Method: Investigators conducted a retrospective chart review of 312 clients participating in the Work Evaluation and Rehabilitation Clinic (WERC) Program from 1994–2000. Only 196 charts were sufficiently complete to be included in the study. Of these 196 prospective clients, 166 began the WERC program and 141 completed the program and were included in the database. Data were gathered from the initial history and evaluations conducted upon admission to the program and from the final evaluation conducted at the time of discharge. Demographic information was recorded. Data from the following assessments were collected: pre- and post-scores for subjective measures of pain using the Oswestry Back Pain Scale and a self-report of pain, the Beck Depression Inventory, the Waddell Sign, and pre- and post-scores of several physical performance tasks. Results: Statistically significant post-test improvements were shown in all six outcome measures used in this study. A decrease in pain correlated with the Floor to Waist Lift test and with the Carrying An Object 20 Feet test. The percentage increase in Waddell's Sign correlated with a decrease in the Carrying An Object 20 Feet test. The Floor to Waist Lift test correlated with the Carrying an Object 20 Feet test. The Oswestry Test correlated with the Beck Depression Scale. There was no significant relationship found between diagnosis of back injury and Waddell's Sign, between either the Waddell's Sign and the Oswestry, or the Waddell's Sign and depression. A regression analysis revealed diagnosis, level of education, gender, and pre-injury work load as significant predictors of improvements made during the work program. Conclusion: The program was shown to be effective as measured by the post-test improvements in all 6 performance tests. Although more research is warranted into the effectiveness of treatment for clients with chronic pain, it appears that there is a relationship between pain and physical performance and pain and depression in clients completing a work hardening program.

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Richling, Dennis E. "A Case of the Utilization of Work Hardening in an Employerʼs Disability Management Program". Journal of Occupational and Environmental Medicine 37, № 4 (1995): 523. http://dx.doi.org/10.1097/00043764-199504000-00140.

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15

Cockburn, Jack T., Frank N. Thomas, and Orbie J. Cockburn. "Solution-focused therapy and psychosocial adjustment to orthopedic rehabilitation in a work hardening program." Journal of Occupational Rehabilitation 7, no. 2 (1997): 97–106. http://dx.doi.org/10.1007/bf02765880.

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Wiegmann, Susan M., and Norman L. Berven. "Health locus-of-control beliefs and improvement in physical functioning in a work-hardening, return-to-work program." Rehabilitation Psychology 43, no. 2 (1998): 83–100. http://dx.doi.org/10.1037/0090-5550.43.2.83.

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Hamami, M. "Proposition d'une loi « hybride » modélisant l'écrouissage du sel gemme." Canadian Geotechnical Journal 37, no. 4 (2000): 898–908. http://dx.doi.org/10.1139/t00-041.

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The work presented in this paper is part of a research program dealing with the thermomechanical behaviour of rock salt. It consists of studying the deferred behaviour by means of multi-step creep tests with changes in deviator and temperature. The test results have revealed the strain-hardening character of rock salt superposed to the influence of temperature and stress. The interpretation of the test results with the model designed by J. Lemaitre, is not completely satisfactory for the entire set of test results because Lemaitre's model is used for the modeling of the viscoplastic behaviour of materials with only one strain hardening variable. Hence, a "hybrid" model introducing a double variable for strain hardening has been proposed. The validation of this model on the creep tests is very satisfactory and confirms the existence of two variables of strain hardening for rock salt behaviour.Key words: rock salt, multi-step creep, strain hardening, J. Lemaitre model.

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Huang, Zhen, Gang Tan, and Xiaowei Yu. "Mitigating Vulnerabilities in Closed Source Software." ICST Transactions on Security and Safety 8, no. 30 (2022): e4. http://dx.doi.org/10.4108/eetss.v8i30.253.

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Many techniques have been proposed to harden programs with protection mechanisms to defend against vulnerability exploits. Unfortunately the vast majority of them cannot be applied to closed source software because they require access to program source code. This paper presents our work on automatically hardening binary code with security workarounds, a protection mechanism that prevents vulnerabilities from being triggered by disabling vulnerable code. By working solely with binary code, our approach is applicable to closed source software. To automatically synthesize security workarounds, we develop binary program analysis techniques to identify existing error handling code in binary code, synthesize security workarounds in the form of binary code, and instrument security workarounds into binary programs. We designed and implemented a prototype or our approach for Windows and Linux binary programs. Our evaluation shows that our approach can apply security workarounds to an average of 69.3% of program code and the security workarounds successfully prevents exploits to trigger real-world vulnerabilities.

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19

Lee, J. H., and Y. Zhang. "A Finite-Element Work-Hardening Plasticity Model of the Uniaxial Compression and Subsequent Failure of Porous Cylinders Including Effects of Void Nucleation and Growth—Part I: Plastic Flow and Damage." Journal of Engineering Materials and Technology 116, no. 1 (1994): 69–79. http://dx.doi.org/10.1115/1.2904257.

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Gurson’s mixed hardening plasticity model (which takes into account the progressive damage due to void nucleation and growth of an initially dense material), with strain and stress-controlled nucleations, was used in a large deformation finite element program to study the plastic flow and damage in the uniaxial compression of cylinders under sticking friction. Effects of strain hardening, nucleation models, yield surface curvature, and geometry on the distributions and evolutions of stresses, strains, mean stress, void fractions, and coalescence are studied in detail. Using Gurson’s isotropic hardening model, positive mean and axial stresses developed at the bulge of the cylinder with growth of voids at latter stages of deformation. Due low stress triaxiality (Σm/σe<0.6) at the bulge, the process is nucleation rather than growth dominated for the majority of the cases studied. At failure, the maximum void fraction at the bulge among all cases studied is 0.085 and is far less than the critical void fraction (≈0.15) for coalescence.

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Burns, John W., Laura J. Higdon, John T. Mullen, David Lansky, and Ju Mei Wei. "Relationships among patient hostility, anger expression, depression, and the working alliance in a work hardening program." Annals of Behavioral Medicine 21, no. 1 (1999): 77–82. http://dx.doi.org/10.1007/bf02895037.

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Woo, Min-A., Woo-Jin Song, Beom-Soo Kang, and Jeong Kim. "Acquisition and Evaluation of Theoretical Forming Limit Diagram of Al 6061-T6 in Electrohydraulic Forming Process." Metals 9, no. 4 (2019): 401. http://dx.doi.org/10.3390/met9040401.

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The current study examines the forming limit diagram (FLD) of Al 6061-T6 during the electrohydraulic forming process based on the Marciniak–Kuczynski theory (M-K theory). To describe the work-hardening properties of the material, Hollomon’s equation—that includes strain and strain rate hardening parameters—was used. A quasi-static tensile test was performed to obtain the strain-hardening factor and the split-Hopkinson pressure bar (SHPB) test was carried out to acquire the strain rate hardening parameter. To evaluate the reliability of the stress–strain curves obtained from the SHPB test, a numerical model was performed using the LS–DYNA program. Hosford’s yield function was also employed to predict the theoretical FLD. The obtained FLD showed that the material could have improved formability at a high strain rate index condition compared with the quasi-static condition, which means that the high-speed forming process can enhance the formability of sheet metals. Finally, the FLD was compared with the experimental results from electrohydraulic forming (EHF) free-bulging test, which showed that the theoretical FLD was in good agreement with the actual forming limit in the EHF process.

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Cole, Keith, Matt Kruger, Dylan Bates, Greg Steil, and Mike Zbreski. "Physical demand levels in individuals completing a sports performance-based work conditioning/hardening program after lumbar fusion." Spine Journal 9, no. 1 (2009): 39–46. http://dx.doi.org/10.1016/j.spinee.2008.07.007.

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23

Shapedko, Alexander Ya. "The program of inclusion in the search activity of older adolescents and youth as a means of social hardening." Vestnik of Kostroma State University. Series: Pedagogy. Psychology. Sociokinetics 29, no. 3 (2023): 9–14. http://dx.doi.org/10.34216/2073-1426-2023-29-3-9-14.

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The article discusses the content component of the implementation of the search activity of older adolescents and young men through modeling and implementation of programs aimed at their social hardening. This process is characterized by a special approach, multi-vector, reasonableness from the point of view of the formation of target settings. At the same time, the program is considered as a local project containing a justification of the idea, a list of basic approaches and principles, a statement of theoretical and practical actions. The variability in the content of the implemented programs in the activities of search teams allowed us to focus on the formation of a model within which it is possible to identify mutually conditioning blocks: target, value-oriented, content-based, technological, evaluative and effective, subsystem (component). The formed model approach makes it possible to assess the potential of involvement in search activities, promotes the formation of participants in such associations to critically evaluate the past and present, their own actions, be ready to overcome difficulties, make independent decisions and take responsibility for it, respond to socially significant events, work in a team. The content component of the program is aimed at solving military-patriotic and socio-pedagogical goals. The variability of the use of the program approach made it possible to include a variety of forms and methods in it, the modularity of the construction allows it to be expanded in time, the number of participants, and the resources involved.

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Suchocki, Cyprian. "On finite element implementation of cyclic elastoplasticity: theory, coding, and exemplary problems." Acta Mechanica 233, no. 1 (2021): 83–120. http://dx.doi.org/10.1007/s00707-021-03069-3.

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AbstractIn this work the finite element (FE) implementation of the small strain cyclic plasticity is discussed. The family of elastoplastic constitutive models is considered which uses the mixed, kinematic-isotropic hardening rule. It is assumed that the kinematic hardening is governed by the Armstrong–Frederick law. The radial return mapping algorithm is utilized to discretize the general form of the constitutive equation. A relation for the consistent elastoplastic tangent operator is derived. To the best of the author’s knowledge, this formula has not been presented in the literature yet. The obtained set of equations can be used to implement the cyclic plasticity models into numerous commercial or non-commercial FE packages. A user subroutine UMAT (User’s MATerial) has been developed in order to implement the cyclic plasticity model by Yoshida into the open-source FE program CalculiX. The coding is included in the Appendix. It can be easily modified to implement any isotropic hardening rule for which the yield stress is a function of the effective plastic strain. The number of the utilized backstress variables can be easily increased as well. Several validation tests which have been performed in order to verify the code’s performance are discussed.

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Majeed, Jafar Ghani, Yasir K. Ibrahim, and Ghada A. Abd Al-Aziz. "Influence of Heat Treatment on Corrosion of Low Carbon Steel in Sulfuric Acid Solutions." European Journal of Engineering Research and Science 4, no. 4 (2019): 64–69. http://dx.doi.org/10.24018/ejers.2019.4.4.1137.

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Different heat treatments such as (Annealing, Normalizing, Hardening in oil, and Hardening in water) of low carbon steel (LCS) specimens were performed in electrical furnace at constant temperature of (850ºC). The aim of this work was to estimate the effect of each heat treatment of LCS specimens on their corrosion rate (CR) in sulfuric acid solutions at constant room temperature of (25±5ºC). The CR was measured, while the acid concentration (Cacid) and immersion time (T) were changed according to experimental plan. Computer program (Statgraphics/Experimental Design) was used to calculate the fitted linear model of corrosion rate of low carbon steel in terms of (Cacid, and T) for each heat treatment separately. The fitted linear models of CR were adequate, while the interactions of the operating parameters were negligible. The R- square statistic indicates that the models as fitted explain 81-93% of the variability in corrosion rate.

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Majeed, Jafar Ghani, Yasir K. Ibrahim, and Ghada A. Abd Al-Aziz. "Influence of Heat Treatment on Corrosion of Low Carbon Steel in Sulfuric Acid Solutions." European Journal of Engineering and Technology Research 4, no. 4 (2019): 64–69. http://dx.doi.org/10.24018/ejeng.2019.4.4.1137.

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Different heat treatments such as (Annealing, Normalizing, Hardening in oil, and Hardening in water) of low carbon steel (LCS) specimens were performed in electrical furnace at constant temperature of (850ºC). The aim of this work was to estimate the effect of each heat treatment of LCS specimens on their corrosion rate (CR) in sulfuric acid solutions at constant room temperature of (25±5ºC). The CR was measured, while the acid concentration (Cacid) and immersion time (T) were changed according to experimental plan. Computer program (Statgraphics/Experimental Design) was used to calculate the fitted linear model of corrosion rate of low carbon steel in terms of (Cacid, and T) for each heat treatment separately. The fitted linear models of CR were adequate, while the interactions of the operating parameters were negligible. The R- square statistic indicates that the models as fitted explain 81-93% of the variability in corrosion rate.

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Kowser, Md A., and Md Mahiuddin. "Determination of Constant Parameters of Copper as Power-Law Hardening Material at Different Test Conditions." International Journal of Applied Mechanics and Engineering 19, no. 4 (2014): 687–98. http://dx.doi.org/10.2478/ijame-2014-0047.

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Abstract In this paper a technique has been developed to determine constant parameters of copper as a power-law hardening material by tensile test approach. A work-hardening process is used to describe the increase of the stress level necessary to continue plastic deformation. A computer program is used to show the variation of the stress-strain relation for different values of stress hardening exponent, n and power-law hardening constant, α . Due to its close tolerances, excellent corrosion resistance and high material strength, in this analysis copper (Cu) has been selected as the material. As a power-law hardening material, Cu has been used to compute stress hardening exponent, n and power-law hardening constant, α from tensile test experiment without heat treatment and after heat treatment. A wealth of information about mechanical behavior of a material can be determined by conducting a simple tensile test in which a cylindrical specimen of a uniform cross-section is pulled until it ruptures or fractures into separate pieces. The original cross sectional area and gauge length are measured prior to conducting the test and the applied load and gauge deformation are continuously measured throughout the test. Based on the initial geometry of the sample, the engineering stress-strain behavior (stress-strain curve) can be easily generated from which numerous mechanical properties, such as the yield strength and elastic modulus, can be determined. A universal testing machine is utilized to apply the load in a continuously increasing (ramp) manner according to ASTM specifications. Finally, theoretical results are compared with these obtained from experiments where the nature of curves is found similar to each other. It is observed that there is a significant change of the value of n obtained with and without heat treatment it means the value of n should be determined for the heat treated condition of copper material for their applications in engineering fields.

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Fedorenkov, D. I., and D. A. Kosov. "Implementation of the Lemaitre damage model with kinematic hardening in the ANSYS finite element complex." PNRPU Mechanics Bulletin, no. 2 (December 15, 2022): 147–57. http://dx.doi.org/10.15593/perm.mech/2022.2.12.

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Currently, one of the most popular in fracture mechanics is taking into account damage and its effect on the stress-strain state of structural elements. In this work, the Lemaitre damage model was integrated taking, into account the combined hardening law, which combines the Armstrong - Frederick kinematic hardening law and the Voce isotropic hardening law, into the ANSYS finite element software. The model is implemented in the form of a dynamically linked library of user material for three-dimensional objects, which is tested on a cylindrical specimen with an external annular notch, both in an axisymmetric setting and in a three-dimensional one. The article presents model representations of the above-listed standard systems. This work demonstrates only one of the two stages of verification of the created program - comparison of damage fields under monotonic loading with data known in the literature - and doesn’t take into account the verification of cycle-by-cycle kinetics of plastic deformation accumulation with experimental data for low-cycle fatigue. The result of verification, consistent with similar experiments known in the literature, is confirmed in accordance with similar experiments. In addition, an analogy was found using the TSL law of the cohesive fracture mechanics approach. Despite the fact that two different types of constitutive equations are used in the cohesive model and Lemaitre, the physical meaning of these equations consists in one thing - visualization and identification of mechanisms and coordinates of damage.

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Tyurina, Vasilina, Anton Chepurnenko, and Vladimir Akopyan. "Prediction of Thermal Cracking During Construction of Massive Monolithic Structures." Applied Sciences 15, no. 3 (2025): 1499. https://doi.org/10.3390/app15031499.

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The problem of early crack formation caused by temperature stresses in hardening concrete is very relevant for massive monolithic reinforced concrete structures. The aim of the work is to develop a method for thermal cracking risk prediction during the construction of massive monolithic reinforced concrete structures. The innovation of the research consists in taking into account the dependence of the concrete elastic modulus and strength on the time and temperature of hardening. The significance of the study lies in analysis of methods for reducing the risk of early cracking using the example of a real structure. The object of the study is a fragment of a massive monolithic dock wall. The analysis is performed by the finite element method using a program developed by the authors in the MATLAB environment. Verification of the developed software was performed by comparison with the solution in ANSYS using a linear elastic model without time dependence of the elastic modulus. Next, various options were used to set the dependence of the mechanical characteristics of concrete on the time and temperature of hardening. An analysis was conducted of the possibility of reducing the risk of early cracking by reducing the length of the concrete block, correcting the heat exchange conditions of the surfaces, and reducing the heat generation of concrete.

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Noh, Dong-Hee, Eun-Ju Jo, Seung-Hyup Han, and Kyung-Yoon Kam. "Effects of Work-Hardening Program on Job Retention in Industrially Injured Workers: Focused on Self-Efficacy, Depression, and Rehabilitation Motivation." Journal of Korean Society of Occupational Therapy 25, no. 1 (2017): 71–83. http://dx.doi.org/10.14519/jksot.2017.25.1.06.

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Puchi-Cabrera, E. S. "Modeling Cold-Rolling Processes of Commercial Twin Roll Cast Aluminum Alloys." Journal of Engineering Materials and Technology 123, no. 2 (2000): 149–54. http://dx.doi.org/10.1115/1.1329873.

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Primary rolling operations of twin-roll cast commercial aluminum alloys can be designed more efficiently on the basis of maintaining a constant rolling load throughout the rolling program. The computation of the final thickness of the strip for every pass can be conducted by means of the simplified theory of Bland and Ford, assuming a constant rolling load during the rolling schedule. Particularly, for twin-roll cast Al-1 percent Mn alloy (TRC 3003) it is possible to reduce one rolling pass if the rolling load is kept constant at about 800 ton. The implementation of this design procedure requires a knowledge of both the work-hardening characteristics of the material and the change in friction conditions throughout the operation. For this last purpose, von Ka´rma´n linear differential equation can be integrated following a more efficient computational procedure based on integrating factors and standard numerical integration methods. Also, the work-hardening characteristics of the material were determined from plane strain compression tests, on the basis of the evolution laws proposed by Sah et al. and Follansbee and Kocks. The rolling pass design that has been proposed could have clear advantages in terms of the productivity of the mill, quality of the rolled products and extension of the rolls life.

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TURKALJ, GORAN, DOMAGOJ LANC, and JOSIP BRNIC. "LARGE DISPLACEMENT BEAM MODEL FOR CREEP BUCKLING ANALYSIS OF FRAMED STRUCTURES." International Journal of Structural Stability and Dynamics 09, no. 01 (2009): 61–83. http://dx.doi.org/10.1142/s0219455409002886.

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In this work, a one-dimensional beam model for buckling analysis of framed structures under large displacement creep regimes is presented. The equilibrium equations of a prismatic and straight spatial beam element are formulated in the framework of corotational description, using the virtual work principle. Although the translations and rotations of the element are allowed to be large, the strains are assumed to be small. The material of a framed structure is assumed to be homogenous and isotropic. The bilinear elastic–plastic model with isotropic hardening and the power creep law are adopted for describing the inelastic behavior of the material. The numerical algorithm is implemented in a computer program called BMCA and its reliability is validated through test examples.

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Virca, Ioan. "Statistical Analysis of Results Obtained in the Hardening Surface of the Metal Powder Materials with Optical Radiation Impulses." Scientific Bulletin 20, no. 2 (2015): 79–85. http://dx.doi.org/10.1515/bsaft-2015-0012.

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Abstract The paper presents how is processed the data resulted from application of pulsed optical superficial treatments on surfaces of materials made of metal powders. The parameters of the electrotechnological regime work are variable in the experimental program, namely the distance between the axis focal energy sources and surfaces play, the number of energy pulses applied to the voltage pulse of optical radiation, which causes a statistical analysis more complex, after which it will precise drawing lessons that will lead to a calculation microhardness model in the superificial layer of material.

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Cetlin, P. R., and J. L. N. Marcos. "Redundant Deformation Factor Evaluation Through the Stress-Strain Curves Superposition Method in Round Section Bar Drawing—Experimental Results." Journal of Engineering Materials and Technology 109, no. 4 (1987): 276–81. http://dx.doi.org/10.1115/1.3225977.

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Based on a previous literature analysis of the stress-strain curves superposition method for the evaluation of the redundant deformation factor φ, an experimental program is proposed and carried out for SAE 1018 steel. The method is applied for tensile and compressive testing, and for multiple and single passes up to 30 percent logarithmic strains. For single passes, results for tensile testing were reasonably in accordance with those in the literature. For multiple passes, work hardening was higher for 2 or 3 passes than for 1 pass, contrarily to results for Copper in the literature. Compression testing should not be used for φ evaluation if one wants to obtain φ values similar to those in the literature.

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Štefan, Jan, Slavomír Parma, René Marek, Jiří Plešek, Constantin Ciocanel, and Heidi Feigenbaum. "Overview of an Experimental Program for Development of Yield Surfaces Tracing Method." Applied Sciences 11, no. 16 (2021): 7606. http://dx.doi.org/10.3390/app11167606.

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This paper develops an experimental technique to evaluate the initial yield surfaces of metallic materials, as well as to study their evolution during plastic flow. The experimental tracing of yield surfaces is necessary for deriving and calibrating more robust phenomenological models of directional distortional hardening. Such models can be used to characterize the behavior of structures experiencing complicated and demanding loading modes, such as multiaxial ratcheting. The experimental technique developed in this work uses thin-walled tubular specimens, along with a servo-hydraulic machine, under various modes of tension/compression and torque. Identification of the onset of plastic flow is based on a small proof equivalent plastic strain evaluated from the outputs of a contact biaxial extensometer firmly attached to a specimen surface. This allows for evaluation of both the initial yield surface, as well as theevolved yield surface after a plastic prestrain. Throughout a test, continuous and fully automatized evaluation of elastic moduli and proof plastic strain is assured through algorithms written in C# language. The current technique is shown to provide promising results to effectively capture the yield surfaces of conventional metallic materials.

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Lee, D. R., and J. M. Bloom. "Assessment of Fully Plastic J and C*-Integral Solutions for Application to Elastic-Plastic Fracture and Creep Crack Growth." Journal of Pressure Vessel Technology 115, no. 3 (1993): 228–34. http://dx.doi.org/10.1115/1.2929521.

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A critical part of the assessment of defects in power plant components, both fossil and nuclear, is the knowledge of the crack driving force (K1, J, or C*). While the determination of the crack driving force is possible using finite element analyses, crack growth analyses using finite element methods can be expensive. Based on work by Il’yushin, it has been shown that for a power law hardening material, the fully plastic portion of the J-integral (or the C*-integral) is directly related to an h1 calibration function. The value of h1 is a function of the geometry and hardening exponent. The finite element program ABAQUS was used to evaluate the fully plastic J-integral and determine the h1 functions for various geometries. The Ramberg-Osgood deformation theory plasticity model, which may be used with the J-integral evaluation capability, allows the evaluation of fully plastic J solutions. Once it was established that the grid used to generate the h1 functions was adequate (based on the more recent work of Shih and Goan), additional runs were made of other configurations given in the EPRI Elastic-Plastic Fracture Handbook. Differences as great as 55 percent were found when compared to results given in the Handbook (single-edge crack plate under tension and plane stress with a/b = 0.5). Effects of errors in h1 on predicted failure load and creep crack growth are discussed.

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Costa, Sérgio, N. Peixinho, and J. P. Mendonça. "Design and Testing of a New Metallic Solution for Toecap Component on Safety Footwear." Applied Mechanics and Materials 44-47 (December 2010): 1460–64. http://dx.doi.org/10.4028/www.scientific.net/amm.44-47.1460.

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This paper explores an innovative solution based on the geometric redesign of integrant safety shoe`s component, the toe cap component. The investigation program covered some steps as the computational modeling of the toecap component, a set of numerical simulations in the FEM context with the toecap model discretization used for multiple Non-Linear Analysis on plastic domain, and experimental tests for ISO EN 20345 certification to support and comparing results. The aim of the study is to explore the work hardening phenomenon of the high strength steel DP600 on toecap component formed, to predict an expected mechanical strength increase and a consequent significant reduction of the weight. The study points to a thickness decreasing value of approximately 50% and equivalent reduce of weight.

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Lee, J. H., and Y. Zhang. "A Finite-Element Work-Hardening Plasticity Model of the Uniaxial Compression and Subsequent Failure of Porous Cylinders Including Effects of Void Nucleation and Growth—Part II: Localization and Fracture Criteria." Journal of Engineering Materials and Technology 118, no. 2 (1996): 169–78. http://dx.doi.org/10.1115/1.2804883.

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In Part I [1] of this paper, Gurson’s mixed hardening plasticity model with strain and stress-controlled nucleations, was used in a large deformation finite element program to study the plastic flow and damage in the uniaxial compression of cylinders under sticking friction. Due to low stress triaxiality at the bulge of the cylinders, it was found that localization may occur before void coalescence. In this paper, necessary conditions of localizations are analyzed for the axial compression of porous cylinders under sticking friction. Shear band type of localization with a normal mode of fracture has been predicted for the majority of the cases studied. Various existing localization conditions and fracture criteria are assessed using the results from the simulation. The maximum shear stress at failure is approximately constant and a constant critical damage can not be found.

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Urriolagoitia-Sosa, G., G. Urriolagoitia-Calderón, J. M. Sandoval Pineda, et al. "Numerical Evaluation of the Crack Compliance Method (CCM) in Beams with and without Prior History." Applied Mechanics and Materials 13-14 (July 2008): 173–82. http://dx.doi.org/10.4028/www.scientific.net/amm.13-14.173.

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This work assesses the Crack Compliance Method (CCM), which has been extensively used for the experimental evaluation of residual stresses, by the Finite Element Method (FEM) to validate its experimental applicability through numerical evaluation. The CCM is a very powerful method that is based on Fracture Mechanics theory, but its experimental application and set up has not been totally scientifically validated. In this paper, a numerical evaluation is presented on the basic applications of the CCM. The assessment of the CCM is performed on bending beams with and without prior straining history. To determine the best position and orientation of the strain gages, as well as the optimum number of readings, a number of numerical simulations where also performed for the correct performance of the experimental evaluation of the CCM. The prior straining history condition, in the analyzed components, is induced by an axial pulling before the beam is bent. Three levels of preloading are considered: low, medium and high (which are related to the yield strain of the simulated material); Isotropic and Kinematic hardening rules are also considered. After the residual stress field is induced by bending, a slot cutting is simulated and the strain relaxation produced is captured, which is used later in the CCM program for the quantification of the original residual stress field. The results obtained in this work, provide a quantitative demonstration of the effect of hardening strain on the distribution of the residual stress in beams. In the same manner, the theoretical formulation of the CCM has been evaluated validating the application of this method for the determination of residual stress fields in mechanical components.

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Shapedko, Alexander A. "Determination of pedagogical conditions for the effectiveness of the use of search activity as a means of social hardening of youth." Vestnik of Kostroma State University. Series: Pedagogy. Psychology. Sociokinetics 29, no. 2 (2023): 37–42. http://dx.doi.org/10.34216/2073-1426-2023-29-2-37-42.

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The article discusses the pedagogical conditions that determine the effectiveness of the use of search activity as a means of social hardening of youth. This process is characterized by the peculiarity of approaches, multi-aspect, its influence on the formation of life attitudes, trajectories of development of young citizens. Search work in this perspective is considered as an effective means to get involved in socially approved activities, expanding the range of formed readiness to solve life tasks, problems. In modern conditions, search activity is based on both the traditional experience of search and patriotic organizations, associations, and active, interactive forms and methods of work on the involvement of young people in civil-patriotic activities. The paper highlights the assessment of approaches to the formation of a meaningful component for the implementation of basic conditions. We attributed to them: the establishment of mutual assistance groups, the orientation of the multi-age community and its members to a personal model of nonviolent interaction, the training of search team leaders in the context of this model, building networking to expand social contacts and exchange life experiences based on dialogue and equality. The allocation of these conditions based on the results of monitoring work has shown its effectiveness and the possibility of applying in practice the work of children's and youth associations of a different orientation. The formed program for the inclusion of participants in the search work is considered by us as a local practice–oriented project built on the basis of modularity, in its structure it has a target, value–oriented, informative, technological and evaluative-effective blocks.

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Kim, Byung Tak, Seon Jin Kim, Sung Wi Koh, and H. J. Kim. "Mechanical Behaviors of a Power Steering Hose Assembly during the Swaging Process." Key Engineering Materials 353-358 (September 2007): 2822–27. http://dx.doi.org/10.4028/www.scientific.net/kem.353-358.2822.

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In this study, finite element analyses for the mechanical behaviors of a power steering hose assembly during the swaging process were performed in order to investigate the stress level of hose components according to jaw strokes, and to examine the effect of friction coefficient on the contact force. The physical properties such as Mooney-Rivlin constants of rubber materials and the work-hardening data of the steel were obtained through the experiments, and the contact conditions identical to the swaging process were taken into account. Two reinforced layers included in the hose were modeled with axisymmetric rebar elements in the general-purpose program, MSC MARC2000. The updated Lagrange formulation and the large displacement option were employed in the analysis. The result interpretations were focused on the rubber components which are in contact with the metal components, because of their important roles in the hose efficiency.

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Kim, Tae-Rim, and Chi-Seung Lee. "Investigation of Density- and Strain Rate-dependent Strain Hardening-softening-coupled material Behavior of Polyurethane Foams using Elasto-viscoplastic Constitutive Model." Korean Journal of Metals and Materials 58, no. 5 (2020): 357–67. http://dx.doi.org/10.3365/kjmm.2020.58.5.357.

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Polyurethane foam (PUF) is one of the most well-known cellular materials and is widely employed in various industrial and biomedical fields thanks to its many advantages. These include mechanical and material characteristics such as low density and thermal conductivity, and high specific elastic modulus and strength. Despite of these advantages, the PUF has extremely complex material nonlinearity, with changes in density and strain rate, which is a major obstacle to material design and the application of PUF-based structures. PUF has elasto-viscoplastic behavior including three stages of material features, linear elasticity, softening/plateau with stress drop and densification. These phenomena depend strongly on strain rate and density. Therefore, in this study, a phenomenological constitutive model, namely, an elasto-viscoplastic model, was proposed to describe the density- and strain rate-dependent material nonlinear behavior of PUF. The yield surface-independent plastic multiplier, and the hardening- and softening-associated internal state variables proposed by Frank and Brockman, and Zairi et al. were adopted in the constitutive model, respectively. The proposed constitutive model was discretized using the implicit time integration algorithm and was implemented into a user-defined subroutine of the commercial finite element analysis program, ABAQUS. At the same time, a deterministic identification method for material parameters of the constitutive model was introduced to predict the precise material response of PUF under arbitrary densities and strain rates. To do this, the three-dimensional constitutive model was contracted to a one-dimensional equation, and the explicit equation for each material parameter was derived. Then, the strain hardening- and softeningdependent material parameters were calculated using experimental results, such as the work hardening ratestress curve and the yield stress-strain rate curve. After analyzing the obtained material parameters, it was found that the material parameters were strongly dependent on the density and the strain rate. Consequently, the macroscopic material response of PUF, such as a uniaxial compressive stress-strain curve, can be predicted based on the proposed method in this study.

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Chotiros, Nicholas P. "Salinity, force chains, and creep in muddy sediments." Journal of the Acoustical Society of America 152, no. 4 (2022): A145. http://dx.doi.org/10.1121/10.0015841.

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The salinity of sediments is not usually measured. Experience with sandy sediments shows that it has no significant effect on the acoustic properties. In muddy sediments, salinity is critical to the skeletal frame, because it causes the clay particles to flocculate, forming an aggregate of larger particles with significant water fraction. It behaves like a granular medium, in which stress is transmitted along random force chains. Mud is known to suffer from creep, and the force chain model fits neatly into creep theory. It may be modeled as a form of stationary creep, which is linear in many respects. No net strain-hardening is involved. The result is a creep model of the skeletal frame that naturally couples into the Biot theory of porous media. It predicts an attenuation that increases linearly with frequency at low frequencies, which is overtaken by viscous attenuation that increases as the second power of frequency and high frequencies. [Work supported by ONR, Ocean Acoustics Program.]

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Nyoman Dwika Ayu Amrita, Agus Wiryadhi Saidi, and Made Mulia Handayani. "Development of Waterfalls and Penikit Hot Springs Tourism Objects in Belok Sidan Village." International Journal of Community Service Learning 6, no. 2 (2022): 185–92. http://dx.doi.org/10.23887/ijcsl.v6i2.40890.

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The attraction of Penikit Waterfall is unique, which is known as a hot and cold waterfall. However, the development of Penikit Waterfall tourism has not sufficiently affected the economy of the local community. The lack of visitors and the lack of information in the wider community about the place is one of the weaknesses of this tourist attraction. In addition, the infrastructure at this tourist attraction is still lacking. For this reason, it is necessary to hold a PKM for the development of Penikit Waterfalls and Hot Springs in Belok Sidan Village, Petang District, Badung Regency. The target partner in this PKM is the Tourism Awareness Group (Pokdarwis) Wana Giri, totaling 33 people. The PKM activities carried out are, repairing toilets (structural work and finishing work), installing clean water for toilets, parking lot cleaning, hardening and cementing hot water pools, making WEB, training on using WEB and simple bookkeeping. The results of the PKM program on the Penikit Waterfall and Hot Springs help increase the economic potential that supports development in the Penikit area in particular, namely: there are business opportunities, there is an increase in income, and there is labor absorption.

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Kopp, R., M. Tschirnich, M. Wolske, and J. Klo¨wer. "Designing Hot Working Processes of Nickel-Based Superalloys Using Finite Element Simulation." Journal of Engineering for Gas Turbines and Power 124, no. 4 (2002): 931–35. http://dx.doi.org/10.1115/1.1494096.

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Knowledge of correct flow stress curves of Ni-based alloys at high temperatures is of essential importance for reliable plastomechanical simulations in materials processing and for an effective planning and designing of industrial hot forming schedules like hot rolling or forging. The experiments are performed on a computer controlled servohydraulic testing machine at IBF. To avoid an inhomogeneous deformation due to the influence of friction and initial microstructure, a suitable specimen geometry and lubricant is used and a thermal treatment before testing has to provide a microstructure, similar to the structure of the material in the real process. The compression tests are performed within a furnace, which keeps sample, tools, and surrounding atmosphere on the defined forming temperature. The uniaxial compressions were carried out in the range of strain rates between 0.001 and 50s−1 and temperatures between 950 and 1280°C. Furthermore, two-stage step tests are carried out to derive the work hardening and softening behavior as well as the recrystallization kinetics of the selected Ni-based alloys. At the end of this work a material model is adapted by the previously determined material data. This model is integrated into the Finite Element program LARSTRAN/SHAPE to calculate a forging process of the material Alloy 617.

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Maliar, Eduard, Nelya Maliar, Natalia Bezpalova, et al. "Hygienic provision of training and physical activity of athletes in adaptive sports." Scientific Journal of National Pedagogical Dragomanov University Series 15 Scientific and pedagogical problems of physical culture (physical culture and sports), no. 3(189) (March 26, 2025): 115–18. https://doi.org/10.31392/udu-nc.series15.2025.03(189).19.

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The article defines and characterizes the peculiarities of hygienic provision of training and competitive activities of athletes with special needs; the content of the system of various hygienic measures in the process of training athletes in adaptive sports is disclosed: a rational daily regimen; optimal socio-hygienic factors of the microenvironment, everyday life; hardening, personal hygiene; optimal conditions for training and competitions; specialized nutrition and rational drinking regimen; auxiliary and hygienic measures to restore and increase working capacity; specialized sets of hygienic measures during the preparation and performance of athletes in difficult conditions; the hygienic principles of building the educational and training process of Paralympic athletes are characterized: systematic training sessions and repeated physical exercises; gradual increase in physical activity; alternation of work and rest; versatile physical training; organizational and methodical approaches to the implementation of the program of corrective and rehabilitation training of athletes with damage to the musculoskeletal system were analyzed; hygienic standards have been determined in terms of equipping places of classes and providing the following special sports equipment; basic types of sports and exercise-tests are defined, which are used in the correction and rehabilitation program to assess the level of physical fitness of athletes with damage to the musculoskeletal system; pedagogical complex control in the process of sports training due to metrological provision of measurements is characterized.

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Kukielka, Krzysztof, Leon Kukielka, Łukasz Bohdal, Agnieszka Kułakowska, Leszek Malag, and Radoslaw Patyk. "3D Numerical Analysis the State of Elastic/Visco-Plastic Strain in the External Round Thread Rolled on Cold." Applied Mechanics and Materials 474 (January 2014): 436–41. http://dx.doi.org/10.4028/www.scientific.net/amm.474.436.

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This work describes the thread rolling as a real object and its physical and mathematical modelling. An incremental modelling and numerical solution of the contact problem between movable elastic or rigid tool and elastic/visco-plastic bodies developed in [ is adopted to the numerical simulation of thread rolling process for the case of rigid tool (threading head) and elastic/visco-plastic body (pipe or bar). An update Lagrangian formulation was used to describe nonlinear phenomena on a typical incremental step. For solution of discrete equations of motions and deformations of the object the explicit integration method was applied. The algorithm and application of 3D numerical analysis in ANSYS program were elaborated. This algorithm let for determination of influence of friction coefficient, initial yield stress and plastic hardening modulus. This factors influence will be carried out with 5 levels rotary experiment plan, which let for elaboration of regression equation to describe this relationship. Exemplary results of 3D numerical analysis of displacement and strain in thread for different conditions of rolling process are presented.

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48

King, P. M. "Outcome Analysis of Work-Hardening Programs." American Journal of Occupational Therapy 47, no. 7 (1993): 595–603. http://dx.doi.org/10.5014/ajot.47.7.595.

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Kruger, Matthew, Mark Lorenz, Avinash Patwardhan, et al. "21. Does functional capability in a sports-performance–based work conditioning hardening program correlate with RTW capabilities at 1-yr follow up with workers compensation subjects SP lumbar fusion." Spine Journal 4, no. 5 (2004): S13—S14. http://dx.doi.org/10.1016/j.spinee.2004.05.023.

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Gribov, D. S., and P. V. Trusov. "The Tree-Level Viscoelastic Model: Analysis of the Influence of the Packing Defect Energy to the Response of Materials under Complex Loading." PNRPU Mechanics Bulletin, no. 4 (December 15, 2020): 60–73. http://dx.doi.org/10.15593/perm.mech/2020.4.06.

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The development of new and improvement of existing modes of thermomechanical treatment of metals and alloys in present conditions is impossible without development of appropriate mathematical models, that allow determining material characteristics during technological processes. Constitutive equations are the core, the main components that determine the quality of such models. Macrophenomenological theories of plasticity relying on processing the results of experiments on macrosamples, have become widespread as such in solving applied problems of solid mechanics. Taking into account the need to describe the memory of processes, the equations of this class have a complicated mathematical structure, require expensive tests (generally speaking, for complex loading) for each material, due to which they are not universal. In the past 15-20 years, constitutive models based on the introduction of internal state variables, of a multilevel approach, and physical theories of inelasticity (plasticity, viscoplasticity) became very popular. Models of this class are focused on describing the evolving structure (including microstructure), which ultimately determines the physical and mechanical properties of materials and constructions. As the physical mechanisms and their carriers are identical for wide classes of materials, the models of this class have significant versatility, including the prediction of behavior of new, not yet existing materials, to study the physical mechanisms of the occurrence of various effects, observed in macro experiments. Hardening is one of interesting effects observed in experiments on complex (including cyclic) loading (as compared to directional loading) of samples, made of various metals and alloys, arising from a significant evolution of the microstructure. Empirical data analysis made it possible to establish that the tendency to manifest this effect is usually experienced by metals and alloys with a low stacking fault energy (SFE). The paper provides a brief analysis of the experimental work and mathematical models describing the response of a material to complex deformation. It is noted that macrophenomenological theories do not allow one to describe in an explicit form the evolution of the microstructure and the carriers of plastic deformation and hardening mechanisms, thus they do not provide an opportunity to explain the physical reasons for the above effects. The purpose of this work is to develop, study and implement a multilevel elasto-visco-plastic model that allows describing the evolution of crystal lattice defects in materials with different SFE under different thermomechanical processing, different strengthening mechanisms at different structural-scale levels. In the framework of constructing a constitutive model, special attention is paid to the development of a submodel, focused on description of the evolution dislocations and barrier densities on slip systems. Kinetic equations for dislocation densities on slip systems make it possible to analyze the nucleation of dislocations due to the activation of Frank - Read sources, annihilation of dislocations of different signs on one slip system, interaction of split dislocations of intersecting slip systems with the formation of barriers. Relations for the description of hardening are given, taking into account the current density of dislocations and barriers. The general structure of the model and the relationship between the parameters of submodels of different levels are considered. An algorithm and a program of implementing the model were developed, the evolution of dislocation densities on slip systems was analyzed, and the intensity of hardening and the formation of barriers on split dislocations were obtained depending on the type of loading.

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Journal articles on the topic 'Work hardening program'

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