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Fatigue damage of internal threads has gradually become the main failure mode of force sensor. To make the internal thread structure of force sensor meet the fatigue performance requirements, the design criteria of static strength and fatigue life are comprehensively considered in this paper.

The variation of static stress and fatigue life with the size of the main structure is obtained by simulation. By changing the number of thread turns, the hub height and outer diameter of the hub, the optimized design of the spoke force sensor is determined.

The experiment was carried out based on the determined optimized structure, and the results showed that the fatigue life meets the design requirements.

This research has certain guiding significance for the design and developments of high-cycle fatigue force sensors.

The purpose of this paper is to explore the possibility of an enhanced continuous liquid interface production (CLIP) with a porous track-etched membrane as the oxygen-permeable window, which is prepared by irradiating polyethylene terephthalate membranes with accelerated heavy ions.

Experimental approaches are carried out to characterize printing parameters of resins with different photo-initiator concentrations by a photo-polymerization matrix, to experimentally observe and theoretically fit the oxygen inhibition layer thickness during printing under conditions of pure oxygen and air, respectively, and to demonstrate the enhanced CLIP processes by using pure oxygen and air, respectively.

Owing to the high permeability of track-etched membrane, CLIP process is demonstrated with printing speed up to 800 mm/h in the condition of pure oxygen, which matches well with the theoretically predicted maximum printing speed at difference light expose. Making a trade-off between printing speed and surface quality, maximum printing speed of 470 mm/h is also obtained even using air. As the oxygen inhibition layer created by air is thinner than that by pure oxygen, maximum speed cannot be simply increased by intensifying the light exposure as the case with pure oxygen.

CLIP process is capable of building objects continuously instead of the traditional layer-by-layer manner, which enables tens of times improvement in printing speed. This work presents an enhanced CLIP process by first using a porous track-etched membrane to serve as the oxygen permeable window, in which a record printing speed up to 800 mm/h using pure oxygen is demonstrated. Owing to the high permeability of track-etched membrane, continuous process at a speed of 470 mm/h is also achieved even using air instead of pure oxygen, which is of significance for a compact robust high-speed 3D printer.

The construction industry has always been regarded as a stressful and task-driven industry with high levels of work pressure. When the stressful situations are prolonged, job burnout becomes unavoidable for construction professionals. The purpose of the present paper is to investigate the critical predictors of burnout among civil engineers at construction sites in Turkey and identify the impact of those determined burnout predictors on various burnout dimensions.

The possible causes of burnout for civil engineers at construction sites were determined using an extensive literature review and were further studied using a questionnaire. The obtained data were analysed statistically using SPSS 22 and LISREL 8.7 software. Correlation analysis, exploratory and confirmatory analysis, and structural equation modelling were performed on this collected data, and a structural model was developed.

Three critical factors affecting burnout levels of civil engineers in construction sites were determined; among them “organisational injustice” and “competitive pricing and lack of contract management” were identified as the critical predictors of burnout in the emotional-exhaustion and cynicism dimensions. Based on these predictors, potential solutions and recommendations are proposed that are anticipated to decrease the burnout among civil engineers at construction sites.

Although there are several works of research regarding the burnout among construction professionals, there is limited research that has provided insight into the specific factors causing burnout among civil engineers. This research presents a structural model of the predictors obtained by a confirmatory factor analysis for decreasing the burnout level of civil engineers at construction sites. The current study represents the first comprehensive quantitative determination of the factors and predictors of burnout among civil engineers at construction sites in Turkey.