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This study aims to examine the feasibility of feedforward actuation of the recoater blade position to alleviate the resin surface non-uniformity while moving over deep-to-shallow transitions of submerged (already cured) geometric features.

A two-dimensional computational fluid dynamics (CFD) model has been used to determine optimized blade actuation protocols to minimize the resin surface non-uniformity. An experimental setup has been designed to validate the feasibility of the proposed protocol in practice.

A developed protocol for the blade height actuation is applied to a rectangular stair-like configuration of the underlying part geometry. The evaluation of the actuation protocol revealed the importance of two physical length scales, the capillary length and the size of the flow recirculation cell below in the liquid resin layer below the blade. They determine, together with the length scales defining the topography (horizontal extent and depth), the optimal blade trajectory. This protocol has also shown its efficiency for application to more complicated shapes (and, potentially, for any arbitrary geometry).

This study shows that incorporation of a feedforward control scheme in the recoating system might significantly reduce (by up to 80%) the surface unevenness. Moreover, this improvement of performances does not require major modifications of the existing architecture.

The results presented in this work demonstrate the benefits of the integration of the feedforward control to minimize the leading edge bulges over underlying part geometries in stereolithography.

This paper aims to explore the fluid flow in the stereolithography process during the recoating step. The understanding of the flow dynamics can be used as an input for an active control of the resin surface height map. The recoating over a rectangular cavity has been considered to investigate the influence of the cavity depth on the resin surface height map.

Two-dimensional numerical simulations have been used to obtain the flow characteristics as function of the cavity depth. An experimental setup, which mimics the recoating process in the stereolithography process, was used to verify the results of simulations and to test the suitability of the 2D model. The surface height profile along the centreline was measured by a confocal chromatic distance sensor and compared to the 2D numerical results.

By means of computational fluid dynamics (CFD) simulation, the flow in the cavity and the free-surface behaviour of the resin was explained for different cavity depths and confirmed by experiments.

The study is focused only on the cavity depth variation to show feasibility and suitability of the presented CFD model and the proposed analytical expression to estimate the layer thickness.

The proposed approach can serve as a tool for designing the closed-loop control for the recoating system in the next generation of stereolithography equipment.

In the present work, the fluid flow behaviour, a source of significant imperfection in the recoating process, has been investigated during the recoating step over a rectangular cavity.

We explore the significance of social ontology and its capacity to inform the specification of organizational status, architecture and capacities. We consider how different conceptions of social ontology are critical for explicating a range of epistemological and socio-economic questions concerning organizations and develop a research agenda oriented to studying these issues from the perspective of management and organization studies.

This study aimed to analyze the effect of Trauma-Focused Cognitive Behavior Therapy (TF-CBT) on the depression level and quality of life of the elderly in an earthquake-affected district of North Lombok Regency, Indonesia.

A Randomized Controlled Trial (RCT) with a population of two elderly groups living in an earthquake-affected district was used in this study. The intervention comprised giving TF-CBT. There were three research instruments applied to determine the variables, namely, the Clinician-Administered PTSD Scale (CAPS-5), the Geriatric Depression Scale 15 (GDS 15) and the World Health Organization Quality of Life-BREF (WHOQOL-BREF). All instruments were adopted and translated using back translation to Bahasa Indonesia, which is appropriate at the suggestion of the WHO. To investigate the effect of the intervention, we used hierarchical linear models (HLM) with intent-to-treat analysis. The patent parameter effect was tested using the Wald test (t-test) with a confidence Interval of 95 per cent.

The final analysis applied CAPS-5 and showed that there was a decrease in the PTSD of the respondents, which was down to only 8 (17.8 per cent) in the post-test. The same situation happened for the depression variable (2.8 per cent) after it was assessed using GDS-15C. The Quality of life (WHOQoL-BREF) variable was divided into Physical (50.7), Psychological (57.1), Social (53.6) and Environmental (45.7). These components show there to be a significant result in terms of improving the quality of life of the elderly victims of the earthquake. The finding highlights that applying TF-CBT in the elderly population can significantly drop post-traumatic stress disorder and depression level and enhanced quality of life.

The intervention decreased the depression level and improved the quality of life of the elderly as found in the six- week follow-up. Longer training and integration with the structured local wisdom could be necessary to better address the mental health of the elderly affected by the earthquake. Moreover, strengthening the role of the family as the primary caregiver is required to improve the outcome.

This is the first study that has attempted to use TF-CBT as a method of treatment for the elderly to decrease their depression and to increase quality of life among the Indonesian elderly who have experienced an earthquake. This paper provides knowledge on the effectiveness of TF-CBT that can be used by therapists to treat depression problems suffered by the elderly in a post-disaster area.