Fabrication of Metal-Reinforced Complete Dentures Using the CAD-CAM Technique

The digital manufacture of complete dentures would greatly simplify the workflow; however, the metal-reinforced complete dentures production method has not been well established. This article describes a technique of fabricating metal-reinforced complete dentures in a milling machine using the geometry guide, a negative impression of the occlusal surface of the metal-reinforced complete denture designed using the computer-aided design software. The geometry guide supports and stabilizes the artificial teeth and metal framework in the correct position in the surrounding resin. Fabrication of metal-reinforced dental prosthesis using the digital technique is possible with this method.

Networks of digital manufacturing of face shields and the Covid-19: design, maker culture and social mobilization

This paper addresses the issue of the configuration of a network for the digital fabrication of personal protective equipment to fight the pandemic of COVID-19. The main aim is to highlight how creative and innovative design practices, based on digital fabrication, have contributed to combat the new coronavirus in Brazil, concerning the design, production and distribution of face shields. The paper is the result of both exploratory, descriptive and qualitative research. In addition to documentary data and revisiting design literature, this work sought to understand the network formation modus operandi for digital manufacture of face shields, based on examples carried out in every region of the country. In conclusion, it argued that these social mobilization networks are based on the assumptions of the maker culture and reveal the potential for an open, distributed and resilient design to face this contemporary and future crisis.

Analysis of temperature control effect in fluidized bed coffee roaster

One of the main sources of economic income in Colombia's agricultural sector is the marketing of coffee with a high contribution to the country's economy. However, trends in coffee industry 4.0 show that the coffee roasting process is where more value aggregation is presented and at the same time is one of the most complex because multiple factors are involved such as grain moisture, volume, variety and heat and mass transfer variables. The main objective of this work was to design and implement a fluidized bed system for the study of the effect of temperature control on the physical properties of roasted coffee from Cauca-Colombia. The development of the work was addressed in 4 sequential phases: CAD design, Digital manufacture, temperature control design and the systems analysis. The proposed fluid bed system features a control system for the RoR (rate of rise) that can be adjusted between 3 to 20°C/min, and provide a prediction in the events of the standard roasting profile (Turning Point, Yellow, First Crack, Development time, Second Crack, Drop).

Changeover Process Assessment of Warp-Knitting Let-Off Equipped with Multispeed Electronic Let-Off System

Warp-knitted fabrics have gained increasing attention due to their excellent properties, and their production is strongly dependent on the warp-based electronic let-off system. Most of the existing control systems are single speed electron let-off structure, which brings a series of issues such as broken yarn, missed needle, and running thread caused by let-off delay, making it hard for manufacturer to produce the required fabrics. To fill the gap, this article proposes a new framework of a multispeed electronic let-off system for warp knitting based on closed-loop control strategy. As a demonstration of the capacity and generalizability of this newly proposed methodology, the 01-type four-channel acoustic vibration analyzer is used to test and analyze the time of switching, the let-off amounts, and the change in warp tension during the process of switching let-off amounts, including the explanation and comparison of difference values of let-off quantities. It is shown that the proposed method for the production of warp-knitted fabrics is a useful method for achieving digital manufacture of warp-knitted fabrics.

TAXONOMY OF THE INDUSTRY 4.0: THEORETICAL AND PRACTICAL CONTRIBUTIONS TO A NEW CONTEXT

Understanding Industry 4.0 is to assimilate the elements that comprise it and to understand the processes necessary to implement it. The objective of this study was to perform a taxonomy regarding the theme industry 4.0, presenting the main contributions, obstacles and perspective regarding the theme. To reach this goal, this study began with a systematic review through the Theory of the Consolidated Meta-Analytic Approach, presenting the main scientific contributions and key factors of success. In the second part, an interview was conducted, with six researchers in the field of industry 4.0, to discuss the results of the scientific literature. There were nine key factors to the success of industry 4.0 (Cyber-Physical Systems (CPS), Internet of Things (IOT), Additive Manufacturing, Digital Manufacture (Simulation), Smart Factory, Big Data and Analytics, Cloud Computing, Digital Security and Advanced Robotics) and the major obstacles to implementing these factors. In addition, the opinions of the specialists were evaluated and categorized them by descending hierarchical classification and confirmatory factorial analysis, offering a practical model of implementation.

Architecture of homeostatic security control for digital manufacture systems based on software-defined networks

The authors have offered the homeostatic control system architecture for digital manufacture security based on the software-defined network technology. We have highlighted the development features of digital manufacture systems and defined the technology advantages of software- defined networks, which allow these networks to be successfully applied with flexible and adaptive topology for a highly efficient new generation of cyber-physical systems. We have also described the main operating principles of software-defined networks in digital manufacture systems. A description of homeostatic security control technology, which includes a combination of engines to provide stability of the system’s internal environment and structural and functional resistance to external disturbances, is provided. We have proposed and described in detail the homeostatic security control system architecture including three generalized components: monitoring unit, decision-making unit, protection and control unit.

Wavelet-analysis of network traffic time-series for detection of attacks on digital production infrastructure

Digital production integrates with all the areas of human activity including critical industries, therefore the task of detecting network attacks has a key priority in protecting digital manufacture systems. This article offers an approach for analysis of digital production security based on evaluation of a posteriori probability for change point in time-series, which are based on the change point coefficient values of digital wavelet-transform in the network traffic time-series. These time-series make it possible to consider the network traffic from several points of view at the same time, which plays an important role in the task of detecting network attacks. The attack methods vary significantly; therefore, in order to detect them it is necessary to monitor different values of various traffic parameters. The proposed method has demonstrated its efficiency in detecting network service denial attacks (SlowLoris and HTTP DoS) being realized at the application level.

Characterization of Planar Dimensional Capabilities in Selective Photopatterning of Diacrylate and Epoxy Monomers

Digital light processing (DLP) can be used as a rapid photopatterning technique with micrometer resolution. To ensure high levels of precision and accuracy, it is required to clearly understand the actual dimensional capabilities in the horizontal plane of a patterning setup. A methodology to assess these capabilities was suggested in this study, and the following parameters were determined: The effective pixel size, the planar dimensional reproducibility, and the dimensional precision in dependence of the angular feature orientation in the x-y plane. Experimental verification of the suggested approach was carried out by using a DLP-based 3D printer. This demonstrated that the nominal pixel size stated in the technical data sheet can deviate from the effective pixel size by more than 1%. Furthermore, dimensional inaccuracies of ±5.1% depending on the feature location within the x-y plane were indicated. The dimensional precision was affected by the angular orientation in relation to the pixel grid, and small errors equivalent to ±0.05 pixels were only achievable with features placed in parallel or diagonal orientation. These results characterize the planar accuracy of DLP equipment and help minimize dimensional errors in the direct digital manufacture of microchannel and strut-like patterns.