Casting Process Improvement by the Application of Artificial Intelligence

On the way to building smart factories as the vision of Industry 4.0, the casting process stands out as a specific manufacturing process due to its diversity and complexity. One of the segments of smart foundry design is the application of artificial intelligence in the improvement of the casting process. This paper presents an overview of the conducted research studies, which deal with the application of artificial intelligence in the improvement of the casting process. In the review, 37 studies were analyzed over the last 15 years, with a clear indication of the type of casting process, the field of application of artificial intelligence techniques, and the benefits that artificial intelligence brought. The goals of this paper are to bring to attention the great possibilities of the application of artificial intelligence for the improvement of manufacturing processes in foundries, and to encourage new ideas among researchers and engineers

Application of Machine Learning in the Control of Metal Melting Production Process

Abstract This paper presents the application of machine learning in the control of the metal melting process. Metal melting is a dynamic production process characterized by nonlinear relations between process parameters. In this particular case, the subject of research is the production of white cast iron. Two supervised machine learning algorithms have been applied: the neural network and the support vector regression. The goal of their application is the prediction of the amount of alloying additives in order to obtain the desired chemical composition of white cast iron. The neural network model provided better results than the support vector regression model in the training and testing phases, which qualifies it to be used in the control of the white cast iron production

Fatigue Analysis Based On Fatigue Failure Approach And Damage Tolerant Approach In Coronary Stent Design

Over the last few decades, cardiovascular stents have emerged as crucial biomedical devices. Stents undergo cyclic physiological loading, which can lead to progressive accumulation of structural damage over time eventually resulting in a stent fracture. Considering the critical role of stents, it is necessary to assess their fatigue endurance and predict a potential premature failure due to fatigue loading. This paper presents a comprehensive analysis of coronary stent design based on both fatigue failure and damage-tolerant approaches. Employing the fatigue failure approach, S-N analysis was conducted to pinpoint the critical zones of the stent. Initial resistance to fatigue was evaluated using Goodman's and Soderberg's criteria. These criteria were applied to principal and effective stresses obtained using the Finite Element Method. Susceptibility to fatigue damage was performed by simulating the initial crack growth, and it was assessed through the Paris power law. The damage-tolerant approach yields more conservative fatigue stress ranges compared to fatigue failure criteria, ensuring safety under standard physiological loading conditions. The presented approach offers reliable insights into stent durability, with potential for further enhancement.The research was funded by the Ministry of Science, Technological Development and Innovation of the Republic of Serbia, contract number [451-03-65/2024-03/200107 (Faculty of Engineering, University of Kragujevac)]

EMG Map for Designing the Electrode Shape for Functional Electrical Therapy of Upper Extremities

Achieving the functional grasp by electrical stimulation using surface electrodes is a demanding task. The innervations of muscles come via ulnar, radial and median nerves. The anatomy of nerve branches connecting various muscles in the forearm differs significantly between individuals. We hypothesize that the anatomical differences between the paretic and nonparetic arms are minimal. Based on this assumption we developed a method where the differences of muscle activities (EMG) between the healthy and paretic arms recorded by the 24-contact electrode within an array define the target zones to be stimulated on the affected forearm. We used special electrode where magnetic contacts allow simple change of the stimulation pads. The examiner positions the magnetic contact on the pads where the EMG differences are maximal. The stimulator delivers asynchronous stimulation to the selected pads. We proved that the method is working in stroke patients by measuring joint angles and the grasping force. © 2019, Springer Nature Switzerland AG.Biosystems and Biorobotics, Vol. 21This is the peer-reviewed version of the following article: Popović-Maneski, L., Topalović, I., 2019. EMG Map for Designing the Electrode Shape for Functional Electrical Therapy of Upper Extremities, in: Masia, L., Micera, S., Akay, M., Pons, J.L. (Eds.), Converging Clinical and Engineering Research on Neurorehabilitation III, Biosystems & Biorobotics. Springer International Publishing, pp. 1003–1007, http://dx.doi.org/10.1007/978-3-030-01845-0_20

Welding of thick-walled steels in a narrow groove

Smanjenje otvora žljeba može značajno doprineti efikasnosti zavarivanja i produktivnosti teških metalnih konstrukcija Uobičajena je upotreba uglova žljeba od 45° i 60°. Smanjenje ugla otvora žljeba smanjuje potreban broj zavara, čime se smanjuje trajanje zavarivanja, potrošnja materijala za ispunu i zaostali naponi i deformacije. Međutim, smanjivanje ugla žljeba dovodi do određenih poteškoća. Teško je kontrolisati luk u uskom žljebu, što može dovesti do problema sa kvalitetom spoja. U ovom radu je prikazano zavarivanje sučeonih spojeva od čelika debljine 22 mm sa uglom žljeba od 20°. Zavarivanje je izvršeno korišćenjem MAG postupkom zavarivanja, uz softversku kontrolu luka.Reduction in groove opening can significantly contribute to welding efficiency and productivity of heavy metal structures. It is common practice to use welded joint groove angles of 45° and 60°. Reduction of the groove opening angle decreases the necessary number of welding passes, thus decreasing the welding duration, filler material consumption and residual stresses and strain. However, groove angle reduction leads to certain difficulties. It is hard to control the arc in a narrow groove, which could lead to welded joint quality issues. In this paper, welding of butt joints made of 22 mm thick steel with the groove angle of 20° is shown. Welding was performed using the MAG procedure, with software controlled ar

Azotobacter chroococcum F8/2: a multitasking bacterial strain in sugar beet biopriming

This study assesses the effects of Azotobacter biopriming on the early development of sugar beet. Azotobacter chroococcum F8/2 was screened for plant growth promoting characteristics and biopriming effects were estimated through germination parameters and the structural changes of the root tissues. A. chroococcum F8/2 was characterized as a contributor to nitrogen, iron, and potassium availability, as well as a producer of auxin and 1-aminocyclopropane-1-carboxilic acid deaminase. Applied biopriming had reduced mean germination time by 34.44% and increased vigor I by 90.99% compared to control. Volatile blend comprised 47.67% ethanol, 32.01% 2-methyl-propanol, 17.32% 3-methyl-1-butanol, and a trace of 2,3-butanedione. Root micromorphological analysis of bioprimed sugar beet revealed a considerable increase in primary, secondary xylem area, and vessels size. Obtained results determine A. chroococcum F8/2 as a successful biopriming agent, and active participant in nutrient availability and hormonal status modulation affecting root vascular tissue. © 2022 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group

Influence of immediate release tablet formulation on dissolution profile of paracetamol

Introduction: Paracetamol is analgesic and antipyretic, which is usually in the form of an immediate release tablet formulations. Therapeutic effects in terms of the speed and intensity of the analgesic effect is dependent on speed of liberation from formulation. Aim: The aim of this work was to determine and compare dissolution profiles of 4 paracetamol immediate release tablet formulations and to determine influence of excipients on kinetic of paracetamol dissolution. Materials and Methods: Dissolution profiles of paracetamol tablets were determined using method with paddles and phosphate buffer pH 6.8 as a medium. Release of paracetamol was followed 60 minutes (using 6 time points). Concentration of paracetamol was measured using UV/Vis spectrophotometric method (243 nm). Dissolution profiles were compared using model-independent method (difference factor and similarity factor), statistic method (ANOVA-based method and pair Student's T-test, p<0.05) and model dependent methods (to determinate the release kinetics of paracetamol). Results: All formulations in the first 45 minutes liberated more than 85 % of the labled content. Formulation D, which contained superdesintegrator, released 90% of the content in the first 5 minutes. Though based on values of difference and similarity factors formulations are, not significantly different, ANOVA-based method showed that formulation A and B, B and C, as well as formulation B and D do statistically differ in all 6 time points, meaning they have parallel profiles. The release of paracetamol from formulations A and D is best described by the first order kinetic model, while the release of formulations B and C by the logistic model. Conclusions: The release kinetic of paracetamol is mostly influenced by the type of superdisintegrants and lubricants. Formulation with superdisintegrant technology OptiZorb® demonstrated fastes release rate and thus it is expected to produce the fastest pharmacodynamic effect.

Diffusion-based kinetic modeling of textile dye adsorption by porous copolymer

Macroporous glycidyl dimethacrylate and ethylene glycol dimethacrylate copolymer functionalized with diethylene triamine, PGME-deta, was tested as adsorbent for removal of Acid Orange 10 (AO10) and Reactive Black 5 (RB5) from aqueous solutions. Diffusion-based kinetic models (intraparticle diffusion, Bangham and Boyd model) were used for interpretation of experimental data.Physical chemistry 2012 : 11th international conference on fundamental and applied aspects of physical chemistry; Belgrade (Serbia); 24-28 September 201

Multiuser Cognitive Radio Networks: An Information Theoretic Perspective

Achievable rate regions and outer bounds are derived for three-user interference channels where the transmitters cooperate in a unidirectional manner via a noncausal message-sharing mechanism. The three-user channel facilitates different ways of message-sharing between the primary and secondary (or cognitive) transmitters. Three natural extensions of unidirectional message-sharing from two users to three users are introduced: (i) Cumulative message sharing; (ii) primary-only message sharing; and (iii) cognitive-only message sharing. To emphasize the notion of interference management, channels are classified based on different rate-splitting strategies at the transmitters. Standard techniques, superposition coding and Gel'fand-Pinsker's binning principle, are employed to derive an achievable rate region for each of the cognitive interference channels. Simulation results for the Gaussian channel case are presented; they enable visual comparison of the achievable rate regions for different message-sharing schemes along with the outer bounds. These results also provide useful insights into the effect of rate-splitting at the transmitters, which aids in better interference management at the receivers.Comment: 50 pages, 15 figures, submitted to IEEE Transactions on Information Theor

Development of a 3D workspace Shoulder Assessment Tool Incorporating Electromyography and an Inertial Measurement Unit - A preliminary study

Traditional shoulder Range of Movement (ROM) measurement tools suffer from inaccuracy or from long experimental set-up times. Recently, it has been demonstrated that relatively low-cost wearable inertial measurement unit (IMU) sensors can overcome many of the limitations of traditional motion tracking systems. The aim of this study is to develop and evaluate a single IMU combined with an Electromyography (EMG) sensor to monitor the 3D reachable workspace with simultaneous measurement of deltoid muscle activity across the shoulder ROM. Six volunteer subjects with healthy shoulders and one participant with a ‘frozen’ shoulder were recruited to the study. Arm movement in 3D space was plotted in spherical coordinates while the relative EMG intensity of any arm position is presented graphically. The results showed that there was an average ROM surface area of 27291±538 deg2 among all six healthy individuals and a ROM surface area of 13571±308 deg2 for the subject with frozen shoulder. All three sections of the deltoid show greater EMG activity at higher elevation angles. Using such tools enables individuals, surgeons and physiotherapists to measure the maximum envelope of motion in conjunction with muscle activity in order to provide an objective assessment of shoulder performance in the voluntary 3D workspace