bluuebunny/crossref_metadata_2025_split huggingface dataset:
Topological optimization of the mobile element structure of Gantry type CNC machine using FEA method
Authors: Petrea L , Stan G 
Published: October 2021

Abstract
Because of the rapid development key industries like aerospace, energy, rail transportation, engineering machinery and other industries there exist a growing demand for high speed and precise manufacturing of large and heavy parts. CNC Machine Tools with kinematical feed chains with great distance between slides, Gantry type, are the main tool to machine large and heavy parts. In such type of machines, the mobile element (the mechanical coupling between the two kinematical feed chains) has a significant effect upon the static and dynamic characteristics of the machine. Deformation of the mobile element has a significant impact upon machining accuracy. A study of the static proprieties and the deformation that effect the mobile element is extremely useful for improving the machining accuracy and efficiency of the machine. The weight of the mobile element it is extremely important and effects the overall dimension and weight of the machine. Using FEA analysis on a 3D CAD model this papers objectives are mesh optimization and topological optimization of the mobile element. This study will show that the topological optimization preformed on the mobile element has reduce the inertial forces, 10 to 30 %, while maintaining rigidity.
Modern manufacturing technology for modular photovoltaic panels: State-of-the-art and future trends
Authors: Polcovnicu RA , Țăranu N , Ungureanu D , Zghibarcea Ș , Hudișteanu VS 
Published: October 2021

Abstract
The technological advancement of the recent years has triggered a significant increase in the global energy consumption. Within this frame, the fossil fuels still account for most of the energy consumption as the renewable energy systems often lack reliability and predictability in terms of total energy supply. These shortcomings may be overcome if various design and manufacturing process optimization methods are applied so as to gain more benefits from the current solar power systems. A modern modular photovoltaic (PV) panel is an assembly of photovoltaic cells mounted in an adaptable framework for quick installation. The photo-voltaic cells use sunlight as source of energy and generate current electricity, which can be harvested directly or through an existing grid. A collection of PV modules can be arranged in any desirable manner to form a PV panel. Also, the implementation of such modern modular systems brings numerous advantages, including the reduction of power transmission cost and the minimization of the global warming problems. This work presents the latest findings related to the manufacturing technology and the equipment train used in the production of modern photovoltaic systems.
An alternative for wind energy conversion using improved Savonius rotor turbine model
Authors: Scheaua F D 
Published: October 2021

Abstract
The current society development is dependent of the planet energy resources and if we take an overview on renewable energies used worldwide it can be said that they are constantly gaining ground. This trend represents an important step forward towards maintaining a clean environment by focusing on capitalizing considerable resources that are sustainable over time, such as solar energy, together with waves and wind force. Regarding the energy production solution based on the atmospheric air masses movements or wind energy, the alternative to the constructive model of horizontal axis turbines (HAWT), currently widely used in wind farms is presented the alternative of using vertical shaft turbines (VAWT) for reduced installed power wind farms. The aspects that form the advantages of these turbines are presented as well as the fact that although they offer a lower power coefficient, they can play an important role for smaller power farms, the investment being at lower values. The basic rotor construction model is based on the SAVONIUS type which has been continuously improved, the results being better in terms of energy performance. A rotor concept that can be used within wind turbines with better performance results compared to SAVONIUS classic model is presented in this paper. The novelty elements consist in the use of a larger number of blades as well as the placing method on the rotor basic circle profile. The numerical analysis results made on virtual rotor model are presented, which highlight the improved values obtained on the analysed model.
Coupling methods and optimal use of modern anti-seismic insulation systems at building and bridge construction structures
Authors: Scheaua F D 
Published: October 2021

Abstract
The construction industry has recorded an unprecedented advance in recent years, especially in the world recent developed countries and this involves the increasing development of insulation techniques against the effects of seismic actions that can threaten the structure integrity at a certain time. Most recent achievements in terms of structure insulation systems are successfully used within building and bridge structures in order to ensure the optimal stability level during a potential earthquake, which allows ensuring a proper safety level both for operation and in terms of investments protection. the protection methods of the structures are directed in two directions, namely in achieving the insulation at the base of the structure by strategically positioning the systems at the base of the structure while the second direction is directed at seismic energy consumption or energy dissipation by using dissipative systems mounted on frames the resistance structure of the building. By combining the action of the two types of mechanical systems, good results can be obtained regarding the behaviour of the structure isolated by the earthquake. The paper presents constructive aspects of the mechanical systems used for the seismic insulation of both building and bridge structures and their functional role in the whole structure to which they are mounted. Through the experimental tests made are highlighted the better results in terms of acceleration for the structure isolated with the composed system. Are emphasized in this manner the protective system role in ensuring an improved behaviour for the structure where is mounted at seismic dynamic motions that can occur in time.
Influence of the positioning accuracy given by the positioning encoder of the CNC machine tools
Authors: Stan G , Stoica A 
Published: October 2021

Abstract
The CNC machine tools are present at a large extent worldwide, for machining by cutting all kinds of work pieces. Their machining accuracy and quality are crucial to obtaining very accurate and intricate work pieces. The accuracy of a CNC machine tool is given by the quality of each and every kinematic linkage/coupling in its structure. This work aims at researching the influence of several constructive and functional factors on the positioning accuracy of a kinematic coupling in the structure of a CNC machine tool. The influence caused by noncompliance with the Abbé principle on the positioning accuracy of a feed kinematical linkage is analysed into detail, both at idle and load running. Out of this research useful conclusions are resulting for the CNC machine tool designers and builders, with respect to optimising several constructive factors, such as the location of the position encoder, location of the ball screw, stiffness of the directional guideways etc., in order to improve the accuracy of the CNC machine tool. The results of the theoretical research have been validated through experimental trials, confirming the impossibility of full compliance with the Abbé on the CNC machine tools.
Investigations on the effect of low temperature cooling on the phase transformations of the EN AW 7075 alloy
Authors: Stoicanescu M , Crisan A , Bedo T , Varga B , Milosan I , Peter I 
Published: October 2021

Abstract
Al-based alloys are very challenging materials, especially in applications where energy and mass reduction are required. In this scenario, EN AW 7075 Al-based alloy can be considered of high interest for different large and thick products. One of the many fields of interest where large geometry dynamic is present is, for example, aerospace, where the alloy structural stability in different conditions is very important. In this paper, the main attention is oriented toward the structural investigation of the EN AW 7075 Al-based alloy in different condition, by differential scanning calorimeter and dilatometry analysis, in order to be able to propose it, as a suitable material for aerospace component production. The analysis on the conditioned and un-conditioned materials has been used to assess the alloy’s performance and to control the evolution of the alloy properties, in specific conditions, important aspect for the targeted application. Some data on the mechanical behaviour of the alloy integrate the study.
Comparative study on the financial implications of a fire fighting intervention on an oil reservoir
Authors: Voicu I , Juganaru E D , Panaitescu V F , Panaitescu M 
Published: October 2021

Abstract
In this paper, the authors determine by calculation, for a storage reservoir design for petroleum products, with a volume of 50,000 m3, the required amount of foam that will be used to extinguish a fire that broke out in it. The reservoir for which the calculation is made is in the park reservoir within S.C. Oil Terminal S.A. Constanta -South Platform. The paper presents the constructive characteristics of the reservoir, for which the calculation is made, the constructive characteristics of the special extinguishing installation, the physico-chemical characteristics of the petroleum substances (gasoline, crude oil), as well as the physico-chemical characteristics of the foaming liquid used for extinguishing the fire. The calculation is made on the basis of the Norm on the fire safety of buildings, Part II Extinguishing Installations Indicative P118/2-2013, as well as on the basis of information from the Methodology for calculating the forces and means necessary for extinguishing fires.
Research on small caliber weapons firing ranges security enhancement considering the projectile-obstacle impact
Authors: Zvîncu N-D , Moldoveanu C-E , Mandache-Dodoiu A-D , Dîrloman F-M , Vedinaș I 
Published: October 2021

Abstract
Weapons systems are used to gain a tactical, strategic, material or mental advantage over an adversary or enemy target. The modern weapons systems are designed to be technologically complex but practical for operator usage. The firing phenomenon consists of a multitude of mechanical and thermodynamic processes with the result being the movement of the projectile towards a chosen target. The projectile movement from the weapon to the point of impact defines its trajectory.
Firing ranges are locations where military personnel is operating certain weapons systems in order to achieve specific results and certain levels of readiness. Due to increasing urbanisation of the areas adjacent to firing ranges, monitoring the projectile trajectory becomes mandatory in order to be able to provide a secure climate for both military personnel and civilians.
It is the purpose of the author to provide the numerical simulation tool (a MATLAB application) which is useful for tracking the projectile trajectory from the muzzle of the weapon to the impacted obstacle. By computing the useful information obtained with the internal and external ballistics, the theoretical trajectory of a projectile can be calculated. In order to get the most accurate values, preliminary knowledge is needed. So by using appropriate tools and software, a projectile’s trajectory can be calculated if the correct values are provided (mass, diameter, initial angle, initial speed). The tool created has different weapons-ammunition specifications and initial conditions parameters loaded that can be combined with the existing drag laws known in ballistics (Siacci law, 1930 law or 1943 law) to describe the projectile movement in atmosphere. As obstacles are defined, similar to the ones existing in a firing range, the tool can assess where the impact occurred and is able to display necessary values (impact points coordinates, velocities, impact angles, etc) while also creating 3D and 2D visualisations on the integrated graphic area. This way, the tool can be used to create impact assessments for specific weapons systems and decisions can be made to enhance the security of the firing range and the firing safety.
Three different firing range configurations are considered for comparison when using certain small caliber weapons used by NATO countries.
Comparison between milling roughing operations in full slotting manufacturing: trochoidal, plunge and conventional milling
Authors: Gómez G , Fernández De Lucio P , Del Olmo A , Martínez De Pissón G , Jimeno A , González H , López De Lacalle L N 
Published: October 2021

Abstract
Manufacturing improvements in terms of manufacturing-chain costs and times reduction are becoming a real need in the industry, especially for roughing operations. To satisfy these industrial requirements, more efficient machining processes have been developed, such as High Efficiency Milling (HEM). According to the above mentioned direction, trochoidal milling appears as an efficient method for roughing operations of full slots. This work presents an analysis in terms of production time between conventional, plunge and trochoidal milling to determine which process configuration is more productive.
Milling angular references and process parameters on fiber reinforced plastics
Authors: Navarro M D , Meseguer M D , Ordeig I , Lluch J 
Published: October 2021

Abstract
Machining of fiber-reinforced composites produces delamination in the workpiece. In bidirectional long fiber fabric reinforced composites, delamination depends on different parameters. In this work, two parameters are studied: fiber orientation angle respect to machining direction and the distance of the warp yarn from the trimmed edge until the next dip below the crossing fill. This work defines angles relating fiber orientation with cutting and feed movements and their relations in a robust way, being applied to edge trimming and grooving operations. On the other hand, for Type II delamination, three different kinds of delamination (constant, uniform pattern variation and random) are studied taking into account fiber orientation, wick size and the fiber orientation angle respect to machining direction.
Latest trends in basalt fibre applications and implications of machining processes
Authors: Domingo R , De Agustina B , Marín M M , Calvo R 
Published: October 2021

Abstract
Lastly the use of basalt fibre as reinforcement in organic matrix composites has had a particular attention. Applications in products intended for industry or for final consumer have been increased. The good thermal and mechanical proprieties in environmental typical and extremes conditions have facilitated such uses. Moreover, the development of cryogenic machining can contribute, as environmentally friendly process, in these materials because are support extremes temperatures. Thus, a systematic literature review has been carried out through PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) methodology. At first approximation, it has allowed to identify the main applications of this material, such as transport sector, in several products types (automobiles, drones, bicycles, among others). Few research groups dedicated to this field have been identified, and they are focused especially on the materials properties. Respect to machining processes, several works have been found and in all of them, the operations were executed in dry and at room temperature. Therefore, a new development is possible through the cryogenic machining in basalt fibre reinforced composites.
On machining of Calmax steel by EDM: an experimental study
Authors: Karmiris P , Papazoglou E L , Leszczyńska B , Zagórski K , Markopoulos A P 
Published: October 2021

Abstract
Electrical Discharge Machining (EDM) is a non-conventional machining process in which the material removal occurs by utilizing thermoelectric energy. EDM’s inherent properties render it a feasible method in machining hard-to-cut materials, like tool steels. The current study presents an experimental study regarding the machining of Calmax, a chromium - molybdenum - vanadium alloyed steel, with EDM. The control parameters are the pulse-on current, the pulse-on time and the open-circuit voltage, while the machining performance was estimated in terms of the Material Removal Rate (MRR), the Tool Wear Ratio (TWR) and the Arithmetic Average Roughness (Ra). The experiments were carried out based on Taguchi DOE and an L16 orthogonal array design. Finally, for the aforementioned performance indexes, Analysis Of Variance (ANOVA) was performed to determine how the machining parameters impact the process’ results.
Preliminary study of the hardening effect and fatigue behaviour enhancement through vibration assisted ball burnishing on C45 Steel
Authors: Velázquez E , Marqués J A , Fernández I , Travieso J A , Jerez R , Llumà J 
Published: October 2021

Abstract
The objective of this paper is to present a preliminary study of the effects of ball burnishing with vibration assistance on cycle fatigue endurance of cylindrical specimens subjected to bending stress and obtain the best input parameters. The specimens were burnished through 6 different combinations of preload force, number of passes and vibration assistance, finding that burnishing while applying a 90-N preload and 5 passes derives in the longest lifespan, being the vibration assistance not significant with this combination. In terms of roughness, it has been proved that the vibration assistance improves the finishing significatively, allowing to reduce the number of passes compared to NVABB and, as optimal ball-burnishing parameters, the 90-N preload and 5 passes combination derivates in a 93% improvement in terms of mean roughness of the surface. It is also been proved the hardening effect provoked by the ball-burnishing, being an improvement estimated around the 51% in the best case.
Enactive manufacturing through cyber-physical systems: a step beyond cognitive manufacturing
Authors: Martín A M , Ávila M J , Aguayo F 
Published: October 2021

Abstract
Cognitive manufacturing, as a paradigm for providing intelligence to manufacturing systems and enabling interaction with operators presents limitations. Manufacturing system requires to be adaptive to machine tools, manufacturing environments and operators. In this line, the enactive approach to cognitive science provides a paradigm for the design of new biologically inspired cognitive architectures. Likewise, the advantages of Key Enabling Technologies and the concept of Industry 4.0 reveal new opportunities for increasing industrial innovation and developing sustainable industrial environments. These technologies are appropriated to overcome the limitations of cognitive manufacturing, because they can achieve the integration of physical and digital systems focused on cyber-physical systems. In this work, an architecture for the sustainable development of enactive manufacturing systems based on holonic paradigm is proposed and its main associated informational model is described.
Validation of the sandblasting process in the manufacturing of precision spheres for non-contact metrology
Authors: Cuesta E , Meana V , Pastur P , Álvarez B J , Zapico P 
Published: October 2021

Abstract
In order to ensure the measurements that can be made with non-contact metrology technologies, it is necessary to use verification and calibration procedures using precision artefacts as reference elements. In this environment, the need for increasingly accurate but also more cost-effective calibration artefacts is a clear demand in industry. The aim of this work is to demonstrate the feasibility of using low-cost precision spheres as reference artefacts in calibration and verification procedures of non-contact metrological equipment. Specifically, low-cost precision stainless steel spheres are used as reference artefacts. Obviously, in order for such spheres to be used as standard artefacts, it is necessary to change their optical behaviour by removing their high brightness. For this purpose, the spheres are subjected to a manual sandblasting process, which is also a very low-cost process. The equipment used to validate the experiment is a laser triangulation sensor mounted on a Coordinate Measuring Machine (CMM). The CMM touch probe, which is much more accurate, will be used as a device for measuring the influence of sandblasting on the spheres. Subsequently, the influence of this post-processing is also checked with the laser triangulation sensor. Ultimately, the improvement in the quality of the point clouds captured by the laser sensor will be tested after removing the brightness, which distorts and reduces the quantity of points as well as the quality of the point clouds. In addition to the number of points obtained, the parameters used to study the effect of sandblasting on each sphere, both in contact probing and laser scanning, are the measured diameter form error, as well as the standard deviation of the point cloud regarding the best-fit sphere.
Experimental investigation of contact forces and temperatures in rubbing interactions of honeycomb interstate seals
Authors: Soler D , Saez De Buruaga M , Arrazola P J 
Published: October 2021

Abstract
The new architecture of high velocity aircraft engines includes labyrinth-honeycomb interstate seals to improve the engine’s stability. To increase these engines capacity a commonly used strategy is to reduce the clearance between the blades and the sealing system. However, this reduction causes non-desired contacts (rubbing) between the rotating and static components of the engine. This rubbing interaction has an adverse effect on the engine life (wear and thermal cracking) and efficiency. In this work, experimental tests were carried out to recreate the rub between an F110 steel fin and a Hastelloy X honeycomb seal. A conventional CNC machine controlled the sliding and penetration velocities, and the interaction forces and fin tip temperatures were measured during the rub. Results demonstrate the dependence that both, interaction forces and tip temperatures, have with sliding and penetration velocities. However, it is clear that this influence is more pronounced in relation to the sliding velocity.
Numerical analysis of necking in stretch-bending based on modified maximum force criteria
Authors: Morales D , Borrego M , López J A , Martínez A J , Centeno G , Vallellano C 
Published: October 2021

Abstract
The necking criteria based on the maximum force principle, such as the Swift and Hill necking models, have been extensively used in the past to study sheet formability. Many extensions or modifications of these criteria have been proposed to improve necking predictions under only stretching conditions. Recently, the authors proposed two approaches to predict necking under stretch-bending conditions: a generalisation of classical maximum force criteria to stretch-bending; and a necking criterion based on critical distance concepts, suggesting that necking is controlled by the damage of a critical material volume located at the inner side of the sheet. Both approaches were evaluated with analytical models and the failure was successfully predicted in different materials, such as steel, brass and aluminium. This work presents a numerical study of the proposed necking criteria in stretch-bending processes with different punch radii. The simulations are validated with experimental tests over H240LA steel sheets.