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Social movements can disrupt existing industries and inspire the emergence of new markets by drawing attention to problems with the status quo and promoting alternatives. We examine how the influence of social movements on entrepreneurial activity evolves as the markets they foster mature. Theoretically, we argue that the success of social movements in furthering market expansion leads to three related outcomes. First, the movement-encouraged development of market infrastructure reduces the need for continued social movement support. Second, social movements’ efforts on behalf of new markets increase the importance of resource availability for market entry. Third, market growth motivates countermovement that reduce the beneficial impact of initiator movements on entrepreneurial activity. We test these arguments by analyzing evolving social movement dynamics and entrepreneurial activity in the US wind power industry from 1992 to 2007. We discuss the implications of our findings for the study of social movements, stakeholder management, sustainability, and entrepreneurship.

In this paper, a 3D DEM program TRUBAL, which is capable of calculating the contact between particles considering friction and local plastic deformation, is employed to study the evolution of internal structure of particle assemblies during the consolidation process. Uniaxial powder compaction process is simulated in a cubic periodic unit cell by applying the strain rate to the individual particles. The selection of the proper time steps in DEM for quasi‐static case is discussed. Results in particle scale (microscopic) are obtained and correlated to the statistical bulk response of the assembly. The effects of the microscopic properties of particles (such as friction, plastic contact) on the bulk mechanical response are examined by numerical tests. Correlations between the microscopic properties of particles and the macroscopic continuum behaviours of compacts are discussed. These discussions make it possible to fit DEM results at a macroscopic scale to the experimental measurements by adjusting the particle properties in DEM calculation. An example test is carried out to demonstrate that DEM results could be fitted properly to the experimental results, in the mean time, also provide some microscopic results which are hard to be measured. DEM has the potential to incorporate the microscopic properties of particles into a proper continuum model to perform combined macro and micro study of the powder compaction process.

As the notions of protean career and job crafting share a common emphasis on self-management, proactivity and customization, this study aimed to examine if the associations between protean career, subjective and objective career success were mediated by job crafting, assessed via its three main dimensions (i.e. increasing structural job resources, increasing social job resources and increasing challenging job demands).

The authors sampled 594 Italian employees using a time-lagged research design: protean career was assessed at T1 and job crafting and career success at T2. Responses were analyzed through structural equation modeling.

This study’s results showed that increasing structural job resources mediated the association of protean career with subjective career success, while increasing challenging job demands mediated its association with objective career success.

In contrast to previous studies, in this contribution, the mediating role of job crafting is disentangled by taking into account its three respective dimensions. Additionally, the authors included both forms of career success as outcomes of protean career. Implications for future research and practical recommendations are presented and discussed.

The purpose of this paper is to investigate the relation among work values and protean and boundaryless career orientations.

A sample of 238 employees aged 16 to 65 years from the French-speaking region of Switzerland completed two different work values scales as well as protean and boundaryless career attitudes scales. To assess the relationships among these constructs, correlations, multiple regression, and exploratory factorial analysis techniques were used.

Results suggested that protean and boundaryless career orientations were significantly positively related to intrinsic, social, and status work values. A boundaryless-organizational mobility orientation was significantly negatively associated with extrinsic/material work values.

Results have important implications for understanding which work values are typically endorsed by people with a protean or a boundaryless career orientation.

The present study contributes to the understanding of protean and boundaryless careers by clarifying the relationships among these career orientations and work values.

This research aims to characterize the tribological behavior of polybutylene terephthalate (PBT) and PBT composites with micro glass beads (MGB) on steel, in dry conditions and on a block-on-ring tester, pointing out the influence of sliding distance and speed. The tribology of PBT and its composites is still in an early stage because this thermoplastic polyester requires accurate technological and thermal treatment.

The composites were produced by ICEFS Savinesti Romania and contain PBT grade Crastin6130NC010 (as supplied by Du Pont), 0.5 […] 1.0 per cent (weight) Relamyd B-2Nf (polyamide grade produced by ICEFS, for a better dispersion of MGB), 1 per cent (weight) black carbon for technological and tribological reasons and different micro glass beads (MGB) concentrations (10.0 and 20.0 per cent weight). Tests were done for different sliding distances (2,500, 5,000 and 7,500 m) and speeds (0.5, 1.0 and 1.5 m/s) and a normal load of 5 N.

The friction coefficient and the wear parameter (as mass loss of polymeric blocks) pointed out a good tribological behavior for these composites. Scanning electron microscope (SEM) images revealed particular aspects of PBT local transfer on steel. Also, 10 per cent MGB in PBT reduces wear, especially for longer distances (75,000 m) and higher speeds (0.5 and 0.75 m/s); the friction coefficient is only slightly increased up to 0.23, being less influenced by the speed and the sliding distance as compared to neat polymer.

PBT and PBT composites could become challengers for replacing materials in applications similar to tested ones. Even the neat polymer exhibits a good tribological behavior. The composites have a lower sensibility to higher speeds and sliding distances for the applied load.

Describes an elastic visco‐plastic finite element formulation that is applied to the modelling of pastes. Comparisons are made with experimental results obtained for a particular paste, plasticine. Special attention is applied to the frictional boundary conditions, for which the usual Coulombic procedure is augmented by a “cohesive” wall friction component. Viscous effects also are considered.

Flatter organisational structures and nonlinear career trajectories mean intrinsic value and subjective career success are increasingly important for motivating, guiding and rewarding contemporary workers. While objective measures of career success have been well explored, more research is needed to understand the dimensions of subjective career success, their relative importance to graduates and potential variations by personal factors. This is critical for supporting graduates’ transition into work and for organisations to attract and retain graduates amid global talent shortages.

Building on assertions of the power to understand how what one seeks in a career affects career achievement, this study investigated the importance and achievement of subjective career success among 324 recent graduates from two Australian universities.

Results include a notable emphasis on financial security and work-life balance, particularly among mature individuals, underscoring the value of adaptable work arrangements. Results suggest shifting priorities, with reduced importance placed on opportunities for innovation and assisting others, potentially indicating a move from collective to more individualised goals. Distinct graduate profiles emerged, showcasing diverse priorities and achievements in subjective career success, spanning from “humanistic” to “self-made” success.

Results underscore the significance of higher education embedding program-wide career development plans across the curriculum, including value-based assessments, labour market analyses and career planning and review processes. Comprehensively supporting students in career development will empower them to explore, understand and actively pursue their career goals in alignment with their values and motivations, enhancing their person-organisation fit, career satisfaction and organisational commitment.

This paper aims to develop a method to improve the accuracy of tolerance analysis considering the spatial distribution characteristics of part surface morphology (SDCPSM) and local surface deformations (LSD) of planar mating surfaces during the assembly process.

First, this paper proposes a skin modeling method considering SDCPSM based on Non-Gaussian random field. Second, based on the skin model shapes, an improved boundary element method is adopted to solve LSD of nonideal planar mating surfaces, and the progressive contact method is adopted to obtain relative positioning deviation of mating surfaces. Finally, the case study is given to verify the proposed approach.

Through the case study, the results show that different SDCPSM have different influences on tolerance analysis, and LSD have nonnegligible and different influence on tolerance analysis considering different SDCPSM. In addition, the LSD have a greater influence on translational deviation along the z-axis than rotational deviation around the x- and y-axes.

The surface morphology with different spatial distribution characteristics leads to different contact behavior of planar mating surfaces, especially when considering the LSD of mating surfaces during the assembly process, which will have further influence on tolerance analysis. To address the above problem, this paper proposes a tolerance analysis method with skin modeling considering SDCPSM and LSD of mating surfaces, which can help to improve the accuracy of tolerance analysis.

The purpose of this paper was to gain a better understanding of wear behaviour of polymethylmethacrylate (PMMA) in contact with 316L stainless steel under different conditions (dry condition, distilled water and Ringer's solution). PMMA is commonly used in low-stress sliding application against metal. The effects of applied load and frequency on the wear rate of PMMA against 316L stainless steel were examined.

Tests were conducted under dry condition, in distilled water and in Ringer’s solution by using reciprocating wear machine. Worn surface morphology and composition was evaluated by scanning electron microscopy.

PMMA wear rate increases with the increase in applied load, naturally. An increase in sliding frequency increases the wear rate under dry condition, but it decreases the wear rate in water and in Ringer’s solution.

The objective of the present work was to gain a better understanding of the wear behaviour of PMMA in contact with 316L stainless steel under different conditions (dry condition, distilled water and Ringer's solution). The effects of applied normal load and frequency on the wear rate of PMMA against 316L stainless steel at various conditions were examined experimentally. This information may have future implications for the design of materials which have a contact with physiological fluid in orthopeadic implants.

Poly‐ether‐ether‐ketone (PEEK), a specialty polymer, does not have any tribo‐utility as a bearing material in a virgin form since it exhibits quite a high coefficient of friction (μ) and stick‐slip behavior. The present paper seeks to deal with the adhesive wear behavior of series of PEEK composites based on inclusion of short fibers of glass (GF) and carbon (CF) and solid lubricants such as Polytetrafluoroethylene and graphite. The studies are focused to examine the role of these ingredients on enhancing PV limit, which is an indication of utility of a tribo‐polymer in severe operating conditions.

The Adhesive wear studies were performed on a pin on disc machine fabricated for high speed, load and temperature conditions. A composite pin slid over a disc of mild steel under two selected sliding speeds (2 and 3 m/s) for an hour. The load was varied in each experiment till the pin showed failure. The performance assessment was done based on multiple parameters such as magnitude of μ and its fluctuations with time, specific wear rate, PV limit, compatibility with the counterface, etc. PV limit was judged by observing either sudden increase in μ or wear rate (or both), deformation of the pin or change in the color of the disc.

It was observed that the neat PEEK exhibited very high and fluctuating μ with very low P‐V limit value (150 Nm/s) and high wear rate (2 × 10⁻¹⁴ m³/Nm). Inclusion of 30 percent CF benefited the strength properties but not the tribo‐performance appreciably. Composite D with a combination of GF (25 percent) and solid lubricants (30 percent) excelled in performance with a wide margin. The highest PV limit along with the lowest μ and lowest wear rate and counterface friendliness proved it to be most promising bearing material for the selected harsh operating conditions.

The composite D, which worked better than the commercial composite in almost all the selected operating conditions, indicates its commercial potential as a bearing grade material for high PV conditions.

Synergism between reinforcement and solid lubricants in right amount led to excellent friction and wear performance which was very well analysed based on worn surface topography.