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The steel industry strives to achieve quality steel with improved mechanical properties. In order to meet these market requirements, steel manufacturers need to streamline technological operations, increase process efficiency and productivity, and improve product quality control. Old iron and scrap metal used in the production of steel come from various sources and special attention should be paid to their quality, in particular, to the content of elements harmful to steel. The paper presents the results of the research undertaken on the use as raw material of the steel-making aggregates, in addition to the classic assortments of old iron of by-products obtained from the processing of iron slats in the form of briquettes. The influence of the quality of waste used was assessed by expanding the raw material base in the context of sustainable development, on steel blanks by investigating the effect on the chemical composition as well as the possibility of recovery of alloying element.

Solderless press-fit technology is increasingly favored over lead-free solder mountings due to cost-effective design benefits amid lead-free regulations. However, its over-constrained nature causes assembly issues and preload stress in pins, leading to fatigue failure under vibration. This paper extends previous research by presenting a method to evaluate the robustness of these assemblies under vibration-induced fatigue, considering assembly-induced stresses as static preload stress. The proposed statistical method uses Monte Carlo simulations to compute the distribution of pin failures due to fatigue, providing a comprehensive analysis that traditional worst-case FEA simulations cannot. This approach aids in identifying worst-case scenarios, predicting failure percentages, ranking designs, and improving design robustness through iterative feedback during the design phase.

Additive manufacturing is spreading rapidly in almost all industries, from household to advanced engineering. Components produced by Digital Light Processing (DLP) are not comprehensively characterized, but exceed the capabilities of many AM processes. Its advantages include the ability to produce highly complex designs, superior precision, fast printing and lower operating costs. The present paper investigates the mode I fracture toughness (KIC) of UV-sensitive resin specimens obtained through DLP process. Single edge notch bending (SENB) specimen were 3D printed and tested according to the ASTM D5045 standard. The influence of printing orientation-PO (0°, 45° and 90°), resin color-RC (white, black and transparent) and corrosive environment-CE (air, water and saline solution) was studied. It was observed that all the studied parameters have some effect on the fracture properties. The highest KICvalues were obtained for 45°-PO, white-RC (1.88 MPa•m0.5) and saline solution-CE (2.24 MPa•m0.5). However, the greatest influence is highlighted by RC (∼92%), while CE (∼32%) shows a minimal effect. The fracture surface of the investigated samples is influenced by the printing parameters.

The paper presents a case study from the automotive industry, namely a part made of Inconel 713C and 18/8 L stainless steel and further focuses on the study and analysis the applicability of the WIG process in the automotive industry. The WIG process chosen for the joining of the two components and all the steps from pre-assembly to the examination part will be presented. In a context where quality and performance requirements are critical, WIG welding is a key element in manufacturing processes.

The paper investigates the characteristics of two different manufactured high temperature brazed coatings using a cobalt based powder applied onto the surface of a stainless-steel substrate (AISI 904L). The coatings are intended to shield components exposed to high temperatures in an atmosphere where wear is expected. Energy dispersive analysis (EDX) together with scanning electron microscopy (SEM) was used to characterise the coating microstructure and morphology, and X-ray diffraction was used to identify the phase composition. Properties evaluations were carried out on the coatings’ surface characteristics, including hardness, erosion behaviour and hot corrosion resistance. The hot corrosion test was conducted at 650°C in a salt mixture that contained 75 wt. % sodium sulphate (Na2SO4) and 25 wt.% sodium chloride (NaCl). Alumina particles were used in the erosion tests, which hit the samples surface with an impact angle of 90°.The degree of corrosion attack, erosion behavior and hardness depended on the microstructure of the manufactured vacuum brazed coatings.

This paper presents experimental research conducted at a factory specializing in the development of aluminum alloys and the semi-continuous production of bars intended for rim manufacturing. The semi-finished products are made of 6082 aluminum alloy and undergo forging processes to obtain rims. The charge load consists of various types of aluminum waste and primary aluminum in different proportions, depending on the quality of the waste in the experimental recipes. The elaboration of the aluminum alloy takes place in melting furnaces with a capacity of 80 tons, equipped with two chambers. The casting is performed using a semi-continuous casting installation, and the cast semi-finished products undergo further heat treatment. The casting process involves the addition of alloying elements, in the form of wire, which serve to refine the structure. Experimental data were processed, and correlations between the qualitative characteristics of the alloy and the elements in the chemical composition, as well as grain size, were analyzed. From the obtained correlation analysis, it is observed that the alloying elements refine the grain size, while the grain size and quality of the resulting product are of interest for industrial practice.

The main purpose of this paper is to present the influence between the crimp height and the resistivity for a crimp joint between a copper contact and a wire copper stranded cable using statistical relevant analysis. The experiment followed the analysis of 45 crimped assemblies grouped in 3 main categories to simulate a potential validation procedure according to the international validation process requirements from: DIN (“Deutsches Institut fu r Normung”) with the corresponding Romanian standard SR EN 60352-2:2006 and SAE/USCAR-21 REVISION 3. The baseline used was the behaviour of the resistivity versus the pre-set crimp height of the crimped joints before and after thermal shock test to enable us to conclude if we have a significant relation between the crimp height of the assembly joint and the resistivity.

This paper presents the strain analysis in a brake pedal manufactured by additive technologies. A commercial plastic pedal made by injection moulding was optically scanned using a scanning system based on fringes projection. The result was a CAD model of the pedal that can be used in both numerical simulations and 3D printing. Two models of the pedal with 100% infill rate and a grid infill pattern were produced by 3D printing on an industrial printer, the difference between the two models is laying in the orientation of the printed part in the printer workspace. Resistive strain gauges were applied to determine the mechanical behaviour of the printed pedals regarding the injection moulded version. To perform a comparative study of the experimentally obtained results, pedals with similar mechanical characteristics to those measured experimentally were analysed numerically by the finite element method. The numerical results showed a good convergence with the experimental results, with relative deviations of 13% for the printed pedal with outer filaments oriented longitudinally to its longitudinal axis, 7.3% for the printed pedal with outer filaments oriented transversely and 2.8% for the homogeneous (injected) pedal. The results also demonstrated the possibility of replacing in the future complex, parts made today by conventional technologies with 3D printed elements having mechanical characteristics allowing them to fulfil a functional role.

All papers published in this volume have been reviewed through processes administered by the Editors. Reviews were conducted by expert referees to the professional and scientific standards expected of a proceedings journal published by IOP Publishing.

The IOP Conference Series: Materials Science and Engineeringjournal contains the peer-reviewed papers presented at the 10thInternational Conference on Advanced Materials and Structures - AMS 2024.

The main focus of the paper is to study the effect of fibre reinforcement on compressive strength and compressive modulus of epoxy granite. To investigate the effect of fibre reinforcement, two compositions were considered likes 20% Epoxy and 80% Granite without fibre reinforcement and 20% Epoxy, 75% Granite and 5% fibre reinforcement. Based on the literature studied, three types of fibre were considered viz. steel fibre, carbon fibre and basalt fibre. Three specimens of each type of fibre i.e. nine specimens and three specimens without fibre reinforcement were prepared. The obtained maximum compressive strength and compressive modulus of epoxy granite without reinforcement is 91.70 MPa and 3.5 GPa for the composition of 20% epoxy and 80% granite. The observed maximum compressive strength of 78.57 MPa for 20% epoxy and 75% granite with 5% carbon fibre reinforcement epoxy granite (CFEG) which is much higher than steel fibre reinforced epoxy granite (SFEG) with 20% epoxy and 75% granite and basalt fibre reinforced epoxy granite (BFEG) with 20% epoxy and 75% granite. The computed compressive modulus is 2.7 GPa for SFEG with 5% fibre which greater than CFEG and BFEG with the same fibre content.

In this paper, the direct and inverse kinematics problems for a particular type of 3-DOF, 3-PSP parallel manipulator are considered. The proposed direct kinematics solution is based on an existing one in the literature, but with an alternative, simplified second stage in the solution’s formulation. An explicit analytical solution of the inverse kinematics problem is also proposed for one of the manipulator’s operational modes, requiring one pass through the direct kinematics solution. The proposed solutions can be seamlessly extended to the inverted parallel structure.

The paper presents some specific features of an electric field in a conductive medium, a theoretical base for numerical field modelling using the finite element method and its application in simulation of the processes in real electromagnetic systems. Application examples are presented, concerning simulations of the processes, taking part in contact resistance welding and insulation in the presence of conductive inclusions.

In this paper we present the theoretical and experimental comparison of two digital controllers intended for stabilization of a two-wheeled robot. The properties of an LQG controller and an LQR controller with H∞filter are evaluated. Using the μ-analysis, we show that both controllers ensure robust stability of the closed-loop system in the presence of unstructured uncertainty. The results from the closed-loop system experimental evaluation confirm the precise work of both controllers.

All papers published in this volume have been reviewed through processes administered by the Editors. Reviews were conducted by expert referees to the professional and scientific standards expected of a proceedings journal published by IOP Publishing.

The paper considers the problem of feedback control design for plants with time delay. The role of the feedback is presented showing its ability to restrict the uncertainty in the plant model. The conditional feedback control structure is introduced and its properties for restricting model uncertainty are discussed. The presence of local feedback makes the conditional feedback structure pertinent for its usage when the plant contains a time delay element. The time delay model is replaced by its Pade series approximation. The key idea is to consider the time delay model as perturbation around its Pade series approximation. This fact allows utilizing the rational function expression in the procedure of controller design, thus avoiding using the irrational function of the time delay for this purpose. It is shown that the conditional feedback control structure gives an alternative than the Smith predictor method for controller design of plants with time delay e−θsin their structure. The efficiency of the presented method is demonstrated by a numerical example.

This paper presents review of a method for receiving information for the rotational speed using the signal gathered from Hall sensors. They are widely used, because of their high performance in the whole operating range. There are shown models and substructures developments and simulation results in Matlab/Simulink.

Recent explosions highlighted the need for a thorough investigation to understand the impact of these explosions on critical infrastructural systems and networks like pipelines. This paper provides an essential understanding for developing safety protocols and interventions, strengthening resilience, enhancing public safety, mitigating socio-economic consequences, and ensuring sustained progress. Shallow buried conduits, crucial for transporting water, oil, and gas over long distances, face explosion risks due to conflicts, sabotage, terrorism, corrosion, and accidental damage. Recent blast incidents in San Francisco and Lagos underscore the devastating effects of conduit malfunctions, necessitating rigorous safety measures and technological innovations. In this research, an empty pipeline measuring 26.20 mm in thickness and subjected to a detonation initiated upon its uppermost surface is emulated, utilising the sophisticated computational capabilities of Abaqus software, integrating principles of computational fluid dynamics. Following a meticulous validation process achieved via mesh refinement analysis, the study expands to scrutinise two additional detonation scenarios — positioned above and below the pipe’s surface — while adhering to a steadfast standoff distance of 25mm. The primary objective of this scholarly endeavour is to ameliorate the deleterious repercussions inflicted upon the conduit by explosive forces, envisioning a scenario where deformation occurs without immediate rupture. To this end, a 0.15 mm thick and 200mm wide laminate composed of composite CFRP with 0°/90° fibre orientation is strategically affixed onto the upper half segment of each pipe model at the impacted region, serving as a fortification measure aimed at bolstering areas of susceptibility and potentially diminishing the magnitude of ensuing blast-induced impairment. Comparative analysis of the pipe’s performance, both with and without the applied laminate, is meticulously conducted to discern the effectiveness of this intervention. The results demonstrate a significant reduction in plastic damage with the utilisation of laminate, with models integrating CFRP experiencing an average decrease of approximately 39.94% compared to those without it. It highlights the efficacy of CFRP in protecting pipeline structural integrity against blast events.

Columns as major structural components, lose strength due to sudden and accidental impacts. Such impacted columns can be restored by retrofitting, which increases their load-carrying capacity and lifespan, rather than reconstructing them. The common method of retrofitting involves externally wrapping the columns with fibre sheets. Numerous research studies have been conducted on enhancing the load-carrying capacity of a column by jacketing it with Fiber Reinforced Polymer (FRP). However, there is a lack of research on retrofitting columns internally to overcome vibrations produced due to impact loading. This paper addresses the retrofitting of a column both internally and externally. The external retrofitting is done by CFRP jacketing, and the internal retrofitting is achieved by developing a damper system to overcome damping forces. The experimental work aims to compare the load-carrying capacity of columns retrofitted internally with dampers and externally with CFRP jackets, with a plain concrete column. Dampers are evaluated based on energy absorption in comparison to plain cement mortar. It was found that energy absorption increased by 50% when the concrete was reinforced with 1mm chopped carbon fibers. Such reinforced concrete behaved as dampers, when placed inside the column to absorb the impact energy leading to a 9% increase in load-carrying capacity. The maximum load-carrying capacity was observed in columns wrapped with CFRP and damped with dampers, showing an increase of 25%. Finite Element Analysis is carried out to compare the experimental results and evaluate the damping property. Retrofitting a new column can enhance its initial load-carrying capacity, this helps in reducing the cross-section and percentage of steel usage in columns, contributing to sustainability. Retrofitting approaches to achieve 9th, 12th, and 13th sustainable goals, this leads to a significant contribution in the construction sector.

Reinforced concrete structures are often exposed to extreme loads, such as those from sudden and accidental impacts. This has led to an increasing interest in strengthening these structures, improving their fatigue performance, and extending their service life, particularly for components like beams. A more sustainable approach to maintaining their functionality involves strengthening and repairing damaged components. Therefore, glass fiber polymers are ideal reinforcements for retrofitting due to their high tensile strength and low cost compared to other polymer substitutes This paper presents the performance of plain concrete beams reinforced externally with glass fiber sheets (GFS) and dampers embedded internally. A unique methodology has been adopted to improve the adhesion between the fiber glass sheets (GFS) and the concrete surface. Two adhesive components utilized are epoxy resin (ER) and epoxy hardener (EH), mixed in a ratio of 9:1. Internally embedded dampers are devices used to resist lateral forces on structures, particularly during impact or sudden loading. The adopted damper technique involves incorporating chopped Glass Fiber during the casting process of the dampers. These dampers are subsequently embedded into beams at point of failure. After the curing of 28 days, all the cast beam compositions undergo flexural test, and dampers are tested for compressive strength. After the dampers have undergone compression testing, a microstructural analysis is conducted using SEM (Scanning Electron Microscope). For further details on stress formation in beams, finite element analysis of Ansys is used to model beams for all beam compositions. Also, sustainability goals are addressed by reducing cement usage in construction by introducing retrofitting in older buildings and using this system to improve the design of newer buildings by reducing overall section sizes

All papers published in this volume have been reviewed through processes administered by the Editors. Reviews were conducted by expert referees to the professional and scientific standards expected of a proceedings journal published by IOP Publishing.

Data-driven models with their associated data learning and training schemes can be utilised for the light metal casting processes. This paper presents the basis of data model building processes along with data training and learning exercises for vertical direct chill casting and high pressure die casting (HPDC) applications. The concepts of efficient database building, data translations and sampling, as well as real-time model building and validations are briefly discussed. Rigorous performance studies were additionally carried out for two real-world case studies. Different combinations of data solvers and interpolators are adapted for the model building techniques, while machine learning schemes are used for data trainings.

Hydrogen is expected to play a decisive role on the way to climate neutral transportation. This paper explores the innovative use of wire arc Directed Energy Deposition (waDED) in the manufacturing of a double walled, vacuum insulated liquid hydrogen storage tank. The study demonstrates the feasibility of the waDED process for the manufacturing of tank shells and furthermore the integration of heat exchanger channels into tank shells. Key findings include the development of a suitable process chain with integration of multiple features to ease manufacturing. However, challenges such as thermal shrinkage of the shells as well as geometrical deviations of the outer tank heat exchanger are encountered. Future research will focus on improvements in the process reliability with regards to geometric accuracy as well as in-depth testing under liquid hydrogen condition.

All papers published in this volume have been reviewed through processes administered by the Editors. Reviews were conducted by expert referees to the professional and scientific standards expected of a proceedings journal published by IOP Publishing.

The paper deals with a windshield wiper mechanism with two parallel rocker blades having a complex topological structure. In the first part of the paper, the mobility of the mechanism is analyzed by means of the simplest formula for planar linkages. Also, the topological structure consisting of adyad and a tetrad has been outlined. In the second part of the paper, a kinema-tic analysis of the multi-contour mechanism is performed, the angular displacements of the two rocker blades being obtained. In this regard the independent contour method has been used, the angular displacements of all kinematicelements of the mechanism being calculated. Moreover, the displacement systems have been derived in order to obtain the velocities and late-on the accelerations of the mechanism elements. Finally, the paper ends with the displaying of the kinematic charts of the mechanism elements of which those with themovement of the two parallel rocker blades are the most wanted. This is due to the requirement of maximization of the wiping surface which is a very important safety issue.

The paper deals with synthesis of the windshield wiper mechanism with one rocker-slider blade. Starting from the kinematic scheme of the constructive model designed by Mercedes-Benz motor vehicle company, a structure analysis on this complex mechanism consisting of three kinematic chains, of which two are articulated bar mechanisms and one is planetary mechanism, has been accomplished. The novelty of this paper consists in the presentation of an optimum synthesis method of the planar bar mechanism in two variants for the wiper blade driving. The first variant is a planar 4-bar mechanism type crank-rocker where the cosines theorem has been applied in order to obtain the lengths of the coupler and the crank. The second analyzed variant is a bi-contour linkage consisting of two 4-bar mechanisms linked in series. Further, the calculation of the planetary gear angular velocity on the complex mechanism with dyadic kinematic chains has been achieved. In order to do this, the immobilization of the planetary carrier method has been applied. Finally, the geometry of the driven linkage of the wiper mechanism type crank-slider which has two mobilities has been studied. A vector equation has been written in order to obtain the length of the variable blade.

The scientific paper introduces original research and unique perspectives on the technical and economic aspects of fuel consumption in motor vehicles. Numerous experts argue that conducting practical experiments, specifically through active determinations, can yield noteworthy outcomes in this domain. To substantiate this viewpoint, the paper includes practical examples of experiments and considerations related to the mathematical model used for validating objective functions. These functions encompass the average fuel consumption in liters per 100 kilometers and the quantity of CO2emitted per kilometer by the thermal engine of motor vehicles. The research also articulates the authors’ stance, citing the World Health Organization’s recommendation to decrease urban traffic speed from 50 km/h to 30 km/h. This reduction aims to mitigate traffic accidents and curb chemical noise and vibration pollution. The study amalgamates results from tests conducted on both urban and extra-urban routes, incorporating eco-friendly driving practices for comparative purposes. The primary focus of the mathematical model is to validate fuel consumption under real driving conditions. The paper concludes with insights and future research directions in modeling.

Accurate vehicle dynamics calculations and simulations require robust estimations of the tyre and rim dimensions. This paper presents some findings on the estimation of tyre radii and rim width for passenger cars, mainly based on the statistical investigation of a large amount of data from tyre catalogues. The tyre free radius calculated with the data contained in the tyre marking code has, in principle, the same value as the tyre free radius obtained from catalogues. Thus, the classical equation is enough accurate for free radius estimation. This paper presents statistical investigations of the data in tyre catalogues and the simple equations found to estimate the static and rolling tyre radii. Moreover, numerical considerations on the proper match of tyre and rim widths are revealed. An important finding is the definition of the ratio between the rim and tyre width and the statistical calculation of this ratio vs. tyre aspect ratio. This method allows calculation of the nominal rim width.

At the beginning of the paper, the quantities that characterize a dynamic system are presented. Based on them, the state equations of the dynamic system are obtained, a system that models an active suspension. The types of used controllers, their block diagrams and the influence of the adjustment parameters on the process are reviewed. Next, numerical applications are made for the study of vibrations on models with 2 degrees of freedom, for an active suspension equipped with PID and LQR controllers. These controllers, as well as the simulation of the two systems, passive and active, were modelled and simulated using MATLAB/Simulink software. The numerical results obtained after the simulation are presented in the form of diagrams. In the end of the paper, it is concluded that the designed active suspension system can improve the ride quality by minimizing the displacement of the suspended mass.

The paper presents the dynamic model with 4 degrees of freedom of an independent suspension with MacPherson type coil springs, taking into account the anti-roll bar. Starting from the constructive scheme, a kinematic analysis necessary to obtain the dynamic model is carried out. The differential displacement equations are obtained starting from the expressions of kinetic and potential energy, by applying Lagrange’s equations. Next, the expressions of the inertia, stiffness and damping matrices and, finally, the matrix expression of pitch-roll vibrations are presented. At the end of the paper, in the numerical application carried out with a calculation program in MATLAB, the influence of the values of the damping constants on the dynamic forces at the wheels is studied. The numerical results are presented in the form of diagrams.

The paper aims to respond to the current requirements regarding the usage of modern virtual analysis tools in accidentology research, presenting the methods of performing the virtual and experimental studies. The main objective of this paper is to determine the movement of the dummy by comparing the kinematic parameters provided by the simulations performed in Madymo with the experimental tests (sled tests). A prototype test device was used to analyse the movement of the dummy in a vehicle cabin at different impact situations of a frontal collision. The experiment was performed for two different cases: with seatbelt and without seatbelt. For the virtual study in Madymo two different setups were prepared in order to obtain the results for both testcases based on a parameterized model. The analysis of the results is performed by comparison, between experimental results and simulation results. Three different phases are taken into consideration in order to make a study of a frontal collision: pre-collision, collision and post-collision.

The paper presents a comparative time history analysis based on the 1D-beam Finite Element Method (FEM) for a thin-walled cold-formed steel structure previously investigated both theoretically and experimentally. The recent earthquake which occurred in Turkey with 7.8Mw and a Peak Ground Acceleration (PGA) of almost 0.5g showed numerous collapses of different types of buildings. Romania has an active seismic area located in the Vrancea region where, in 1977 a 7.5Mw earthquake also occurred. In this context, this paper presents a comparative analysis with time history accelerograms of the recorded earthquake in North – South and East - West directions. The structural model was analyzed in Robot Structural Analysis software in two scenarios of the time history accelerograms considering also the P-Δ effect. The finite elements of the structure were defined as 1-D beam elements with hinged joints and limited axial stiffness previously obtained in past studies. The results showed a substantial increase in terms of displacements and stresses.

Currently, almost all car manufacturers have in the production scheme at least one vehicle model with a hybrid or electric energy source. This fact is generated by the high interest in the market related to the subsidies offered to the purchase by the states but also by the high performance in terms of pollution, noise, and economy, which they can achieve. The only performance indicator which for the moment is not at a satisfactory level is represented by autonomy. At this point, the electric cars have an autonomy between 250 and 800 km driven after a single charge of the traction battery. It should be mentioned though that, the autonomy of electric vehicles declared by European manufacturers is obtained in laboratory conditions, these being carried out in accordance with the provisions of the European Union regulations. Obviously, there are significant differences between the electric autonomy obtained in laboratory conditions and the autonomy obtained in real driving conditions. These differences are related to the ideal test conditions achieved at the laboratory level and which cannot be fully found in real driving conditions. Starting from these premises, in a first part of the paper, are presented the theoretical arguments regarding the determination of autonomy in real driving conditions with a driving profile specific to the RDE testing and are described the technical details of the electric vehicle under investigation. In the second part of the paper, are presented the results of the experimental research for the three driving zones specific to the RDE testing: driving in the urban zone, driving in the rural zone, and driving on the motorway. The downward evolution of the state of charge of the traction battery for each driving zone is shown graphically. Following the processing, analysis and interpretation of the data acquired from the car electronic control units, are formulated conclusions regarding the causes that influence the electric autonomy.

The paper investigates vibration testing methodologies for automotive tapered roller bearings. The European Union regulations have indirectly led to improvements in the NVH performance of the bearings that affect both the industrial and automotive markets. The goal of this study was to examine the influence of localized small defects on the vibrations’ magnitudes within tapered roller bearings. A Rockwell indenter was used to create three different surface defects. These three levels, representing different indentation pressures, mimic defects that could occur during manufacturing or bearing installation. Indents were placed on inner raceways, the outer raceways, and the roller bodies. After the assembly of the components, different vibration testing methodologies were applied to quantify those types of defects. This paper presents a new envelope analysis approach to monitoring for defects. The paper presents the current Fast Fourier Transform (FFT) testing approach, whereby the machine sensitivity is representative of a typical quality control bearing thresholds. This paper also presents a new, more robust method and analyzed for its suitability in the detection of localized defects.

The paper presents the integrated propulsion system implementation steps on a L6E road vehicle. The implementation followed several technical levels which are properly described within the paper. The functional behaviour in terms of electric propulsion was defined and developed. All the dedicated components were investigated, set and customized, to equip a L6E vehicle. Currently the electric machine, the battery pack, the user interface, the speedometer, the pedals, the power electronics etc. are implemented on a real existing L6E road vehicle, after they were defined and virtually tested.

All papers published in this volume have been reviewed through processes administered by the Editors. Reviews were conducted by expert referees to the professional and scientific standards expected of a proceedings journal published by IOP Publishing. The papers were reviewed for the scientific content, the novelty of the informations, language correctness and the paper format.

With the increase the number of vehicles on European roads, the road transport has become the biggest source of air pollution in the cities of the old continent. According to European Commission estimates in 2018, more than 39% of NOx (nitrogen oxides) emissions and 10% of PM2.5 and PM10 emissions (mechanical particles with diameters of 2.5 and 10 micrometers) were attributed to road transport. It is known that, in order to limit to some extent, the uncontrolled increase in harmful emissions from road vehicles, the European Commission has gradually introduced new pollution standards to be met by manufacturers of new vehicles. In the second half of 2022, the Commission presented a new proposal to reduce pollutant emissions from new vehicles sold in the European Union (EU), defining the new Euro 7 pollution standards. Compared to Euro 6 by 2035, according to European Commission estimates, these new Euro 7 standards, together with a progressive increase in the number of electric vehicles sold, aim to reduce pollutant emissions from private vehicles and vans by around 35% for NOx emissions and around 13% for particulate emissions. Therefore, both the Euro 7 and CO2emissions standard (CAFE) for vehicles have been designed to improve air quality in cities and reduce greenhouse gas emissions, including by increasing the use of electric vehicles. Starting from this hypothesis, the first part of the paper presents the experimental model developed in the AMESim simulation platform of a mid-size vehicle equipped with a hybrid GMP, tested on a roller bench, which simulates pollutant emissions in this new Euro 7 standard. In the second part of the paper, the simulation results and possible causes influencing hybrid GMP behavior leading to the evolution of pollutant emissions are analyzed. Finally, the paper formulates conclusions on the evolution of pollutant emissions.

Sustainable transportation solutions are more crucial than ever because of the pressing need to increase resource efficiency while lowering greenhouse gas emissions. The most recent advancements in the e-cycle sector have made a significant contribution to this goal and have attracted the interest of numerous businesses that offer mobility services. This paper discusses the main topics surrounding pedal electric cycles (PEDELECS) with an accent on a niche application, namely e-cargo cycles. The paper highlights not just the defining characteristics of these categories, but also other relevant aspects such as barriers to market penetration, general legislation, benefits for specific applications, as well as the significance of incentives, local infrastructure, and urban policies. Based on the available literature, it can be concluded that PEDELECS have a considerable potential to contribute to sustainability goals in urban areas due to their numerous benefits (functionality without emissions, less space occupied on roads, ability to access destinations with increased precision, ability to travel in car-restricted areas, lower costs compared to conventional vehicles, added health benefits to the users, versatility etc.). However, there are also significant challenges and barriers that must be overcome before they can see widespread adoption.

Carbon fiber reinforced polymer composites are important and widely used material in today’s manufacture and automotive. It produces a high demand to research the material, therefore industrial sectors can improve. Developing industry and strict requirements leads us to use this type of material in different applications where we need to use bonding technologies. The exploration of bonding technologies is necessary, and adhesive bonds offer a promising alternative. This paper examines the adhesive bonding of carbon fiber composites using a high strength two-component epoxy.

All papers published in this volume have been reviewed through processes administered by the Editors. Reviews were conducted by expert referees to the professional and scientific standards expected of a proceedings journal published by IOP Publishing.

The present investigation is part of a comprehensive failure study of friction stir welding (FSW) tools, where experimental non-destructive and destructive evaluations are combined with analytical- and physical- simulations of tool wear mechanisms. This paper focuses on the research methodology and the primary results of Gleeble simulations of thermal- and mechanical-cycle effects on an H13 steel material widely used for FSW tools for welding aluminum and magnesium alloys.

With the advent of automated, continuous filament placement technologies, the possibilities for reinforcement placement in composite manufacturing have been further expanded, as the reinforcement path can be continuously varied within the layer. This allows far more efficient structures to be created, resulting in a further reduction in the weight of the structure compared to conventional composites. At the same time, this manufacturing freedom also poses a major challenge for the structural design of composite components, as simulation methods based on meso-level homogenization are mostly not usable due to the lack of periodicity of the reinforcement structure. In our paper, we have established a structural modelling method using finite element analysis (FEA) for fused filament fabrication-based additive manufacturing of continuous fiber–reinforced composites. For modelling the reinforcement structure properly, we used the base-coordinate sweep (BCS) modelling method and for capturing progressive failure mechanisms we used Ansys LS-Dyna with the MAT54 material card. Based on the simulations and tests performed, we demonstrated that the method we present is suitable for the engineering modelling of continuous fiber–reinforced 3D printed composites.

This paper focuses on the application of Value at Risk (VaR) estimation techniques in the context of energy commodity trading, with a specific emphasis on the NYMEX (NG) and Title Transfer Facility (TTF) natural gas index. The primary point of this study is to break down and assess the VaR assessment strategies and recognize the most reasonable methodology. Historical price data for these commodities were collected, and forward prices were generated using a Long Short-Term Memory (LSTM) forecasting model. A portfolio comprising Future and Forward contracts for both NG and TTF index was constructed and three VaR estimation approaches: Variance-Covariance, Historical Simulation, and Monte Carlo Simulation were employed. Backtesting was then performed using the metric Quadratic Probability Score (QPS) to determine the optimal approach. Sensitivity analysis was also conducted to evaluate the variation in the estimated VaR values. The VaR values were determined using all three methods at different confidence interval and their backtesting was performed. The study found that the Monte Carlo Simulation approach outperforms other methods for estimating VaR in risk-averse trading scenarios with lowest QPS. It also underscores the need to consider individual contract risks within a portfolio, suggesting that diversification alone might not suffice in mitigating those risks.

Pipelines have become a major part of energy infrastructure, which requires a secure and reliable means of maintenance. It has become critical to introduce advanced robotic methods for inspecting pipelines in order to offer a more secure alternative to human entry and facilitate deployment of specialized visual inspection devices. This paper primarily deals with the design and development of a simple wall-pressed robot capable of detecting visual defects inside pipelines of diameters ranging from 38 cm to 65 cm. The overall structure of the robot is divided into two segments, each equipped with a three-wheel module arranged 120° from the central axis. Static structural analysis for strength optimization is performed using finite element method. Poly lactic acid plastic and aluminium alloy are selected as structural materials for lightweight design. Real time forces on the robot structure are simulated by applying fixed supports at the holding frame, – 33.85 N compressive forces at the wheel ends of the linkage in the axial direction and placing 145 gm weight at the motor linkage. Motion simulations are carried out to study functionality of driving mechanism. A robot prototype is built and powered by 11.1 V 5200 mAh LiPo batteries. Experimental testing is conducted in a steel pipe of inner diameter 38 cm to validate the robot’s design, assessing traction, gradeability and operational robustness. Testing results are validated with calculated results that the robot applied a tractive force of 26.26 N to the in-pipe wall against each wheel during normal operation and maintained a uniform velocity of 30 mm/sec in horizontal test. This robot has the potential to ensure the safety, reliability and affordability of operations in oil and gas pipelines.

Langtang, a popular tourist destination in Nepal’s northern Himalayas, relies heavily on solid fuels like coal, wood, and LPG, accounting for 99.3% of its energy demand. This reliance is a significant source of greenhouse gas emissions and deforestation. The proposed study provides a green alternative by utilizing heat that would otherwise be squandered with benefits including avoided cost of energy, through which the use of surplus and wasted heat energy, and reduced investment in individual household or building heating equipment. This paper conducts a feasibility study to assess technical and economic viabilities of introducing a solar water heater reinforced rural heat grid network in the region. The technical feasibility of this system is determined using TRNSYS and Polysun to see if the proposed system provide at least 60% solar fraction in all seasons, while economic analysis is conducted using Benefit Cost Ratio (BCR) and discounted payback period. A pilot project was carried out for five households for demonstration, which showed that the heating demand of each house could be met by 40 different 15-tube solar collectors, resulting in energy savings of 2,28,000 kWh and reducing 25,423 kgs of CO2annually. The financial analysis revealed a BCR of 1.45 and a payback period of 14 years, showing that heat grid network is techno-economically viable for rural communities of Nepal.

Nepal’s heavy-duty vehicle fleet relies entirely on imported fossil fuels, posing significant environmental risks due to high particulate matter (PM) emissions. Battery-powered alternatives are unsuitable for large fleets due to trade-offs between range and vehicle weight, which is not an issue for hydrogen-powered fuel cell electric vehicles (FCVs). Shifting to hydrogen fuel offers a promising solution for sustainable, emission-free heavy-duty vehicle operation. Fuel cell buses (FCBs) represent a transformative step in transportation, prioritizing environmental protection, decarbonization, and achieving net-zero carbon emissions by 2045. This paper reviews the critical components for developing an on-site hydrogen refueling station (OHRS). It analyzes the power requirements of vehicles operating on inclined roads based on vehicle modeling. By studying existing diesel buses on the route, the specifications needed for FCBs are determined. It involves Excel-based calculations of fuel demand, vehicle drive cycle modeling, infrastructure assessment, and capacity determination for a fleet of ten hydrogen buses. The analysis reveals that the maximum tractive power required is 119.85 kW, with buses averaging a velocity of 6.8 m/s, reaching a maximum of 20.75 m/s, and achieving a maximum acceleration of 0.96 m/s2. The average motor power required is 13.09 kW, with a maximum of 151.48 kW. Each bus requires 8 kg of hydrogen per day, necessitating an OHRS capable of producing 80 kg per day for a fleet of 10 buses. Consequently, the sizing of components such as the electrolyzer, compressor, storage, and dispenser is dictated by a hydrogen production flow rate of 4 kg per hour. This study provides a comprehensive framework for implementing and operationalizing OHRS to support the deployment of FCBs in heavy-duty transportation.

With ever-increasing concerns over environmental hazards, energy security, and, fleeting reserves of petroleum-based fuel, dimethyl ether (DME) has been under scrutiny as an alternative fuel, which is a high-efficiency compression ignition fuel with minimal NOx, SOx, and particulate matter emission. This paper explores the efficacy of biomass gasification as a method to synthesize dimethyl ether. The impact of steam and pure oxygen on syngas production has been studied, along with an analysis of how temperature affects the yield of DME. A process simulating software, ASPEN PlusV10.0, was used to simulate the synthesis process using the Langmuir-Hinshelwood-Hougen-Watson (LHHW) model. The direct (one-step) method has been studied where methanol synthesis and dehydration of methanol over a catalyst occur in a single plug flow reactor. Both steam and oxygen increased hydrogen production. Steam reduced CO and increased CO2production, whereas oxygen enhanced CO and decreased CO2production. From a biomass of 10,000 kg/hr, a yield of 4,583 kg/hr of dimethyl ether was achieved through the utilization of steam and oxygen as gasifying agents. A tentative economic analysis has been performed to understand the feasibility of the project. The CAPEX amounted to 64.7 million USD, while OPEX amounted to 28.9 million USD. It yielded an annual rate of return of 10.46%. The purity of DME was measured at 98.89%.

Numerous studies and research projects have been conducted to develop natural fiber polymer composites. The researcher and engineers develop a composite by reinforcing natural fiber with a polymer that exhibits the desired mechanical properties. The experiment determines the composite’s mechanical properties, such as tensile, compression, flexural, and impact strength. This paper presents the experimental study of the natural fiber-reinforced composite, where hemp and jute fibers were reinforced with epoxy polymer as the test specimens for the experiment. The primary approach involved fabricating composite samples with fiber-weight fractions and matrix compositions. Then the appropriate sample is experimented with for its tensile strength, compression strength, and impact strength. Another property of the composite’s the composite’s water absorption was investigated through a water absorbability test. Key results show that composites containing a 30% weight fraction of natural hemp fiber demonstrated promising mechanical properties. This composite showed a tensile strength of 50 MPa, a compression strength of 55.6 N/m2, an impact strength of 58.9 kJ/m2, and a water absorbability of 7%. These results may offer valuable insight into the mechanical behavior of natural fiber composites, which can be used to optimize material design and engineering applications. Understanding the limitations and strengths of these composites allows for informed decision-making in selecting appropriate materials for specific engineering projects.

This paper presents a comprehensive study of application of different machine learning techniques for the prediction of turbine faults in an early stage. As the need to ensure an optimal turbine operation through early stage fault detection grows, precise predictive models using machine learning techniques are also increasing rapidly. This study primarily focuses on development and evaluation of the predictive models capable of anticipating fault phases using different range of classification algorithms. It assesses the effectiveness of different classification methods including Support Vector Machine (SVM), K-Nearest Neighbors (KNN), Random Forest, and Convolutional Neural Networks (CNNs) to predict distinct turbine phases. These algorithms are evaluated on experimented dataset encompassing various stages of faults. The results from the algorithm show that CNN was accurately predicting the particular turbine fault phases achieving 80% accuracy with a small length of time series. The deep learning capabilities of CNN capture intricate spatial patterns in turbine data enabling them to discern fault indicators eluded by traditional machine learning methods. The insights gained from this research helps to extend the application of machine learning approaches in the field of turbine fault detection, paving the way for more precise and dependable early failure detection systems.

Gait analysis is the study of human motion during walking or running. It is often used to evaluate and treat individuals with movement disorders or to assist in the design of prosthetics and other assistive devices. The phase detection aspect of gait allows for the quantification of gait characteristics, assessment of effectiveness of interventions and monitoring the changes in gait over time. The objective of the paper is the design and development of a Force Sensing Resistor (FSR) embedded insole that can be placed in shoes for detection of phases during the human gait and its classification. The classification using FSR is achieved by placing sensors at strategic locations on the foot, to detect the forces applied during walking. The data collected by these sensors are used to identify specific phases of the gait cycle—particularly heel strike, midstance, toe-off and swing, by analysing the patterns of data during movement. The layout and number of FSRs is determined through literature review and is followed by the insole fabrication. The wireless transmission of gait data through the FSRs is actuated for ten healthy adults. Machine Learning (ML) program is consequently developed based on all available classification algorithms of supervised learning namely—Logistic Regression, Naïve Bayes, Decision Tree, Random Forest and Support Vector Machine (SVM). The algorithm is trained and tested on separate FSR data sets from which the predictive decision in each gait cycle is attained. In the phase classification aspect, SVM, Naïve Bayes, and Random Forest achieved the highest accuracy of 91.54%, followed by Decision Tree at 90.77% and Logistic Regression at 89.23%. In conclusion, the optimal number of FSRs and their location in smart insole for gait phase detection is resolved. Gait phase classification is also attained. FSR embedded insole thus, provides a promising solution in accurately identifying and categorizing gait phases.