The Annals of “Dunarea de Jos” University of Galati. Fascicle IX, Metallurgy and Materials Science

A Comparative Evaluation of Technical, Financial, and Imaging Performance Between 1.5 Tesla and 3 Tesla MRI Systems for Clinical Applications

Mihaela MARIN, Roxana OPREA, Florin-Bogdan MARIN — Mon, 15 Sep 2025 00:00:00 +0300

This paper presents a structured comparative assessment between 1.5 T and 3 T Magnetic Resonance Imaging (MRI) systems, focusing on technical specifications, economic impact, and diagnostic image quality. Data compiled from manufacturer documentation and clinical usage evaluations reveal that 3 T systems provide higher spatial resolution, improved signal-to-noise ratio (SNR), shorter image acquisition times, and reduced artefact levels. However, these advantages come with substantially increased acquisition and operational costs. The study concludes with recommendations tailored to clinical needs, highlighting that 3 T systems are suited for advanced imaging applications, while 1.5 T platforms remain economically viable for standard diagnostic procedures.

Research on Creating Decorative Objects from Glass Waste Through Thermoforming

Beatrice Daniela TUDOR — Mon, 15 Sep 2025 00:00:00 +0300

The paper presents a research study on the production of decorative glass objects using the thermoforming process. For this purpose, glass waste was used, aiming at the recovery and reuse of various glass scraps for the production of ornamental objects. The thermoforming process was applied to various combinations of white and coloured glass with inserts from different materials to achieve the most pleasant visual impact, producing different shapes and geometries.

Studies and Research on Obtaining Glass Inlays in Metal

Beatrice Daniela TUDOR — Mon, 15 Sep 2025 00:00:00 +0300

The paper presents research on obtaining glass inlays in metal, with the aim of obtaining a decorative object, using the intarsia technique. For this purpose, we studied the samples that we made from glass shards of different sizes, over which different metal oxides were added to colour the glass. The samples were made with different amounts of metal oxide, respectively 4%, 7%, and 10% to obtain different shades of colour. We also conducted experimental research to achieve the embedding of some pieces of glass in a defined metallic contour. The decorative object was made through the thermoforming process, with the glass intarsia in metal, in a stainless-steel plate, used as a background.

How Blockchain Can Reshape the Supply Chain of Steel for an Industrial Complex

Ștefănică FRANGU, Ioan ȘUȘNEA — Mon, 15 Sep 2025 00:00:00 +0300

Steel is an integral part of modern infrastructure and is present in buildings, vehicles, and machinery. Although ubiquitous, the process of converting raw materials into usable products is highly advanced and, in almost all instances, largely unseen. Blockchain can ensure secure, transparent ledgers are maintained throughout each step of the process, from mining and processing to production and export. This enables companies to verify the origin of the steel, the processes undertaken during its production, and its conformity to safety and environmental standards.
This article demonstrates how blockchain is transforming the steel sector by accelerating, simplifying, and making the tracking process more environmentally friendly. It presents the advantages and disadvantages of applying digital technology to traditionally analogue businesses, based on real-world cases and research.
Readers will learn how a conventional business, with a history spanning centuries, is beginning to capitalize on digital opportunities - whether in manufacturing, IT, or even in industrial processes - making it especially relevant to those passionate about technology.

Numerical Simulation and Optimization of Aluminum Die Casting for Enhanced Part Quality

Florin-Bogdan MARIN, Gheorghe GURĂU, Florin TURCU, Mihaela MARIN — Mon, 15 Sep 2025 00:00:00 +0300

This paper investigates the injection process of aluminium alloys through a virtual simulation approach, aiming to optimize technological parameters for improved product quality. The study focuses on the behavior of the molten material during cavity filling, highlighting aspects such as flow uniformity, temperature distribution, and areas prone to defects like porosity and shrinkage. A threedimensional model of the mould and the part was analysed to assess the influence of the injection gate’s positioning and geometry. The simulation results revealed critical regions associated with turbulent flow and uneven solidification. Several design iterations were carried out to reduce structural imperfections and achieve balanced mould filling. The outcomes of the study offer a set of recommendations for improving the performance and reliability of aluminium injection processes, supporting efficient and defect-free production in industrial applications.

Simulation-Based Design of Parametric Origami Structures for Blast and Ballistic Protection

Florin-Bogdan MARIN, Gheorghe GURĂU, Lucian GRIGORAŞ, Mihaela MARIN — Mon, 15 Sep 2025 00:00:00 +0300

This paper investigates the use of parametric origami structures as multifunctional protective layers for lightweight armoured vehicles. Three geometries—Miura-Ori, Kresling, and Waterbomb—were developed as fully parametric CAD models and evaluated under different threat scenarios. Finite element simulations were performed to assess their structural response to vertical blast loads, lateral shaped-charge impacts, and vibrational excitation. Results show that the Miura-Ori panel reduces transmitted acceleration by 58% under simulated IED conditions and provides vibration damping up to 0.82 mm at the center. The Kresling configuration absorbs lateral shocks with 45% pressure attenuation through controlled torsional collapse. The Waterbomb matrix reduces vibroacoustic amplitudes by over 20% across the 100-800 Hz range. A 3D printing orientation study was also conducted, revealing the need to optimize supports for manufacturability. The study confirms that origami-based, parametrically driven designs offer promising performance-to-weight advantages and adaptability for modular armour systems.

Development and Testing of a Seismic-Responsive IoT-Based Safety System for Gas Distribution Networks

Florin-Bogdan MARIN, Cristina-Daniela STAICU (MĂRIAN), Mihaela MARIN — Mon, 15 Sep 2025 00:00:00 +0300

This paper presents the design and experimental evaluation of a smart safety system intended to mitigate seismic risks in urban gas distribution infrastructure. The proposed solution integrates an ESP32 microcontroller with an MPU6500 inertial sensor to detect ground vibrations associated with seismic activity. Upon exceeding a calibrated threshold, the system autonomously triggers the closure of a solenoid valve, thereby halting gas flow and reducing the risk of leaks or explosions. Sensor data is transmitted wirelessly using MQTT protocols to a cloudbased interface for real-time monitoring and logging. The prototype demonstrates rapid actuation, low latency, and high sensitivity to motion events, confirming its suitability for scalable deployment in residential or municipal gas pipeline networks. The implementation relies on low-cost hardware, open-source software, and edge processing to ensure both affordability and autonomous operation in critical infrastructure applications.