A socio-technical view of performance impact of integrated quality and sustainability strategies

This research seeks to examine the direct effects of social and technical integration on deployment of quality and sustainability management programmes and the indirect effect of those on quality and sustainability performance. We also seek to test the spillover effects of quality and sustainability management programmes on sustainability and quality performance, respectively. Socio-technical systems (STSs) theory is used to test the role of social and technical integration on quality and sustainability management programmes. The framework of integrated management system, as supported by both STSs and complementarity theory, is used to test the direct and spillover effects of quality and sustainability management programmes. A large multi-country sample is used to empirically test our theory-induced hypotheses. The findings support that social and technical integration are indeed significant enablers for the positive relationships that quality and sustainability programmes have on quality performance and sustainability performance. Specifically, the results show that while social integration has both direct and indirect effects on quality and sustainability performance, technical integration impacts quality and sustainability performance only through the mediation effect of the respective programmes. The results do not support the spillover effects of quality and sustainability management programmes on sustainability and quality performance. Implications of the findings on academic knowledge and managerial practice are offered.     

Control of tip-to-sample distance in atomic force microscopy: a dual-actuator tip-motion control scheme

The control of tip-to-sample distance in atomic force microscopy (AFM) is achieved through controlling the vertical tip position of the AFM cantilever. In the vertical tip-position control, the required z motion is commanded by laser reading of the vertical tip position in real time and might contain high frequency components depending on the lateral scanning rate and topographical variations of the sample. This paper presents a dual-actuator tip-motion control scheme that enables the AFM tip to track abrupt topographical variations. In the dual-actuator scheme, an additional magnetic mode actuator is employed to achieve high bandwidth tip-motion control while the regular z scanner provides the necessary motion range. This added actuator serves to make the entire cantilever bandwidth available for tip positioning, and thus controls the tip-to-sample distance. A fast programmable electronics board was employed to realize the proposed dual-actuator control scheme, in which model cancellation algorithms were implemented to enlarge the bandwidth of the magnetic actuation and to compensate the lightly damped dynamics of the cantilever. Experiments were conducted to illustrate the capabilities of the proposed dual-actuator tip-motion control in terms of response speed and travel range. It was shown that while the bandwidth of the regular z scanner was merely a small fraction of the cantilever's bandwidth, the dual-actuator control scheme led to a tip-motion control system, the bandwidth of which was comparable to that of the cantilever, where the dynamics overdamped, and the motion range comparable to that of the z scanner.     

Effect of Zirconium on the Densification of Reactively Hot‐Pressed Zirconium Carbide

Densification mechanisms involved during reactive hot pressing (RHP) of zirconium carbide (ZrC) have been studied. RHP has been carried out using zirconium (Zr) and graphite (C) powders in the molar ratios 1:0.5, 1:0.67, 1:0.8, and 1:1 at 40 MPa, 800°C–1200°C for different durations. The volume fractions of phases formed, including porosity, are determined from the measured density and from Rietveld analysis. Increased densification with an increasing nonstoichiometry in carbon has been observed. Microstructural and X‐ray diffraction observations coupled with the predictions of a model based on the constitutive laws governing plastic flow of zirconium suggest that the better densification of nonstoichiometric compositions arise from the higher amount of starting Zr and also the longer duration of its availability for plastic flow during RHP. Volume shrinkage due to reaction between Zr and C and the gradual elimination of the soft metal phase limit the final density achievable. Based on these observations, a two‐step RHP carried out at 800°C and 1200°C leads to a better densification than a single RHP at 1200°C.