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The paper deals with experimental researches concerning micromachining through ultrasonically aided electrical discharge machining (μEDM+US) of an advanced material, comprising a base metal from Ti and superficial nanometric layers from TiO2, i.e. Titania nanotube arrays. The material was investigated by scanning electron microscope. The chemical composition of machined samples was determined by X rays spectrometer energy dispersive. The roughness of machined surface was studied using a profile surface instrument. A comparison was made between the results obtained by classic μEDM and μEDM+US in terms of surface roughness, and craters microgeometry.

The paper presents new methods of smart regional development, starting from a question and one answer: How do we go about building our local smart ecosystem? Make one step at a time. This step is achieved through a number of seven elements: the SMEs network, the relations between universities and the labour market, the efficient using of transport infrastructure, the interactions specific to the various forms of capital with accent on intangible assets, smart relocation, online and offline interactions in smart communities, the used of young staff as a source of creativity and innovation, oriented to smart specialization, leading to sustainable competitive advantage.

This study investigates the thrust force (Fz) and torque (Mz) in a drilling process of an Al7075 workpiece using solid carbide tools (Kennametal KC7325), depending on the effects of crucial cutting parameters such as cutting velocity, feed rate and tool diameter of 10mm, 12mm and 14mm. Artificial neural networks (ANN) methodology is used in order to acquire mathematical models for both the thrust force (Fz) and torque (Mz) related to the drilling process. The ANN results showed that the best prediction topology of the network for the thrust force was the one with five neurons in the hidden layer, while for the case of Mz the best network topology for the prediction of the experimental values was the one with six neurons in the hidden layer. Based on the results acquired, the ANN models achieved accuracy of 1,96% and 1,95% for both the thrust force and torque measured, while the R coefficient for the prediction model of the thrust force is 0.99976 and 00.99981 for the torque. As a result they can be considered as very accurate and appropriate for their prediction.

The paper deals with comparative study between plasma and laser cutting of different materials. C 45 and stainless steel were cut by these mentioned above technologies with different working parameters. The surface quality was studied using scanning electron microscopy. The comparison was extended in the same manner, at laser cutting of some polymeric materials like PVC and Plexiglas. COMSOL Multiphysics, Heat transfer module was used in a dynamic variant with a sweep parameter as machining time in connection to feed rate, aiming at improvement of output technological parameters at plasma and laser cutting. A Gaussian distribution of the energy on laser and plasma spot was introduced as boundary conditions, as well as thermal characteristics of the studied materials. The quality of machined surface was considered based on moderate heating of the material. Some values of working parameters were established due to computerized modelling. These were validated by experimental results. [ABSTRACT FROM AUTHOR]

The paper deals with finite element modelling of micromachining CoCr alloys by ultrasonically aided electrical discharge machining. This hybrid machining process has two components: a thermal one due to EDM, and a mechanical one to ultrasonic assistance. Both components were modelled using Thermal and Structural Mechanics time dependent modules of Comsol Multiphysics. The results were compared with the experimental data obtained in our laboratories, proving a good agreement and offering some solutions for machining optimization.

Starting from the role of new technologies in the development of engineering innovation, this paperwork has two main research directions with respect to creativity and innovation in engineering education. These are based on a combination of creative techniques with traditional engineering education methods. The first component of our research presented herein aims the use of creative methods such as Creative Training and Image Streaming, and the second component of the research statistically analyses the Social Media posts regarding the use of Cloud Computing technology as a support for innovation. The aim of combining such lines of research will lead to the emergence of specific knowledge needed to identify and implement new creative techniques in engineering human resources. Applying such creativity techniques within groups of students can result in innovative ideas usable in ongoing research projects, in certain deadlock situations on finding critical solutions to overcome blockages.

The paper deals with researches of microtopography obtained at different working modes at ultrasonically aided micro-electrical discharge machining (μEDM+US) and pure micro-EDM, using both commanded and relaxation pulses. Images of machined surface taken with scanning electron microscope were analyzed in correlation with chemical composition of samples detected by X rays spectrometer. This led to some explanations of material removal mechanism, aiming at improvement of process modelling and performances increase of μEDM+US.

In this article, we present a novel approach for pattern recognition by using graph theory and its application in mechanical engineering. One of the most important characteristics of the microstructure of a material is the grain size. The analysis of structure is based on statistical methods and on the principle: from the general image of the structure to the particular (individual grains) by averaging. With computer methods, material structure is characterized by analyzing each grain. When using computer software tools it is also possible to analyze the area occupied by a certain structure directly, without the need for approximate calculations, as well as automatically create a report file. The aim of this paper is to present a new methodology; a novel approach for pattern recognition by using graph theory and its application in the analysis of grain size distribution values. These values were obtained from SEM images of robot laser-hardened specimens using estimating methods to calculate the fractal dimension of 3D objects and calculating the density of 3D visibility graphs. [ABSTRACT FROM AUTHOR]

The strategic management of an innovative organization is the process in which managers establish long term orientation, propose performance objectives, develop strategies for achieving the objectives in accordance with the factors involved, internal and external. The external environment defines the vicinity of innovative organization and consists of those elements that directly influence it and over which it can exert a significant influence. In parallel with the analysis of external environment, the organization must carry out an assessment of commercial, productive, innovative, financial, organizational and human potential. Thus, it is possible to determine its ability to deal with threats and capitalize on opportunities. The analysis of external and internal environment must be followed by the construction of scenarios that represent an adequate solution by elaborating a set of alternatives of future of innovative organization that could materialize. The SWOT analysis of innovative organization evaluates the strengths and weaknesses of internal environment, respectively the opportunities and threats from the external environment. [ABSTRACT FROM AUTHOR]

Aspects concerning the intangible resources in machines building industry wishes to highlight aspects of the state of play of the machines building industry within the European economy and taking as an example Siemens, one of the most representative organizations in the industry, to make a brief analysis of the organization in a few more important points. The longstanding presence of this organization in a top position in the market evolves owes its strategy to paying particular attention to intangible resources, achieving and maintaining over time a sustainable competitive advantage. [ABSTRACT FROM AUTHOR]

This research deals with the electrochemical behavior of the advanced material Ti6Al4V in 5% NaCl electrolyte solution as well as the smoothing of the semi-finished front surface by the ultrasonic cyclic stress-inducing effect on the microgeometry peaks. Laboratory experiments were carried out on the estimation of electrochemical parameters in relation to the studied material. The smoothing of the front surface was made by varying the distance between it and the end of the ultrasonic chain and also the energy consumption on the ultrasonic chain. Computerized models were developed using the finite element method of the material removal mechanism using ultrasounds, aiming to explain the specific phenomena of ultrasonic cavity in electrolytic environment. [ABSTRACT FROM AUTHOR]

Intuitive Surgical is the pioneer and a global technology leader in robotic-assisted, minimally invasive surgery. The company develops, manufactures and markets the Surgical System da Vinci, the most complex device used in medical robotics. The product is called "da Vinci" because Leonardo da Vinci invented the first robot, and his works excel in anatomical details. The Surgical System da Vinci is a robotic platform that allows complex surgery through incisions of 1-2 cm. So far, hundreds of thousands of surgeries have been performed. The Surgical System da Vinci reproduces the surgeon's movements in real time. The advantages of using the Surgical System da Vinci, are greater precision, a much better picture and remote surgery. The disadvantages to traditional techniques are that it cannot be programmed and cannot make decisions on its own to make a surgical move or surgery without the surgeon's command. The Surgical System da Vinci is used currently in major medical centers around the world. [ABSTRACT FROM AUTHOR]

The conceptual design stage involves a compound set of objectives and constraints such as issues of function, aesthetic and ergonomics. Furthermore, computational design methodologies offer a great number of advantages for engineering and manufacturing processes. Through the coupling of conceptual design stage with parametric modelling methods, the present research aims towards a non-conventional design technique that enhance product designers' contribution to developing innovative and useful everyday products based on parametric design creations. The suggested approach allows a valuable perception of the design objectives and reinforces product designers in their decisions to find solutions. This research presents a number of illustrative case studies from interior design point of view (e.g. furniture and decorative items). Finally, the paper concludes with suggestions for further research and development for the coupling conceptual design and parametric modelling methodology. [ABSTRACT FROM AUTHOR]

The paper deals with finite element modelling (FEM) of complex shape ultrasonic (US) horn that has its end a wire tool-electrode used for micro-drilling by ultrasonically aided electrical discharge machining (EDM+US). The US horn is the technological component of an ultrasonic chain actuated by a sandwich PZT transducer supplied from 40 kHz generator. The shape and dimensions of ultrasonic horn was determined through several stages of FEM modelling strategy, aiming at obtaining the resonance condition of ultrasonic chain, i.e. the equality between natural frequencies of the sandwich PZT transducer and the US horn with included tool. The influence of different constructive conditions of US horn on its natural frequency and amplification were established in order to replicate the modelling strategy for other horn complex form. Finally, the measurements related to resonance conditions validated the strategy of FEM modelling creating conditions of CAM application for horn achievement. [ABSTRACT FROM AUTHOR]

The paper deals with concentrated energy (nonconventional) machining as technological response to ultraminiaturization challenge, namely micromachining and even nanomachining. Electrical discharge machining (EDM) has proved the opportunity to decrease the machined surfaces dimensions in nanorange (1...999 nm) at lower costs than other nonconventional machining. The finite element modelling of EDM process demonstrated the possibility that a single discharge could create a crater whose transversal dimension is lower than 999 nm. [ABSTRACT FROM AUTHOR]

The paper deals with finite element modelling (FEM) of material removal mechanism due to ultrasonically induced cavitation in the working gap at finishing modes of electrical discharge machining. The influence of some workpiece geometries (shape and dimensions) was studied from the point of view of the optimum value of ultrasonic pressure exerted by shock waves produced by cumulative microjets stage, aiming at obtaining a decrease of machined surface roughness at electrical discharge machining finishing aided by ultrasonics (EDM+US). This is in strong correlation with the consumed power on ultrasonic chain, a key-parameter of working finishing mode. By its appropriate adjustment, the surface roughness at EDM+US can be reduced with almost 50% against that from classic EDM. All these technological issues were supported by FEM results. [ABSTRACT FROM AUTHOR]

The paper deals with finite element modelling (FEM) of material removal mechanism due to ultrasonically induced cavitation in the working gap at finishing modes of electrical discharge machining. The peaks of machined microgeometry are removed, having lower shearing resistance than the other parts of microgeometry, thus the surface roughness being reduced. Experimental data are presented that indicated an optimum value of power consumed on ultrasonic chain, including the electrodetool, at which a minimum value for surface roughness was obtained. This corresponds to a pressure developed by collective implosion of the gas bubbles from the working gap, produced by shock waves oriented along the working gap, parallel to machined surface. This ultrasonic effect is considered a cycle pulse fatigue load on the flanks of microgeometry profile. [ABSTRACT FROM AUTHOR]

The paper deals with technological performances increase at electrical discharge machining aided by ultrasonic longitudinal vibrations of electrode-tool (EDM+US), in terms of machining rate and machined surface roughness. Some experimental data are presented in relation with finite element modelling of EDM+US material removal process. The machining rate could be increased by growing the probability to overlap the pulse time on cumulative microjets stage (CMS) - the effect of ultrasonically induced cavitation in the frontal gap. The surface roughness could be decreased through optimization of a keyparameter of working mode, the consumed power on ultrasonic chain. All these technological improvement with market impact on EDM users segment, very sensitive to cost level, are feasible if the organization applying this hybrid technology (EDM+US) valorizes the connected intangible assets, operable through some main competencies, technology, supplying, marketing, innovation, quality assurance, continuous costs decrease provided by accumulated know-how and patents series in EDM field. [ABSTRACT FROM AUTHOR]

The paper deals with an integrated method for evaluation of intangible assets applied to Small and Medium Enterprises (SMEs) activating in research, through which they aim at obtaining sustainable competitive advantage (SCA). The intangible assets are strictly connected to competencies, which if are distinctive relative to competitors, represent a major option to SCA achieving. The elaborated method based on Producer Matrix needed to evaluate intangible assets in connection with competencies is integrated with products evaluation, based on Customer Matrix, and also with decision method based on Risk Cube. Another evaluation method with qualitative-quantitative character was described based on best practices leading to SCA achieving. [ABSTRACT FROM AUTHOR]

The paper reveals the technical solutions adopted for the design of hydrostatic equipment to replicate the electro discharge machining feed motion. Such equipment is very usefully in, at least two cases. A first case is when machining by electro discharge in difficult angular positions, in order to avoid using special fixturing devices. Using such device can result in significant costs reduction. A second case refers to the case of machining oversized workpieces, which cannot be installed on medium or small sized usual electro discharge installations. Based on functional specifications and elaborated technical documentation, a fully functional model was achieved. Experimental tests revealed a good accordance between the performance requirements and measured ones. The equipment is working properly, from the point of view of EDM system command response both in continuous and pulsed regimes. Further researches should be carried out on equipment with multi-place operation mode. [ABSTRACT FROM AUTHOR]

The paper deals with determination through Finite Element Method (FEM) of a profiled ultrasonic horn for vibrating a disk shape workpiece at ultrasonically aided electrical discharge machining. This approach comprises several stages, starting from applying mathematical relations for preliminary determination of a basic profile stepped horn. The next stages are fully based on FEM modelling the horn profile, using Comsol Multipysics, changing successively different constructive elements of the horn, and adding at its end, the workpiece to be vibrated at electrical discharge machining aided by ultrasonics (EDM+US), which is integrated part of ultrasonic chain. This method uses as entry data the dimensions and natural (own) frequency of transducer subassembly - component of ultrasonic chain - and covers the needed stages to meet the critical resonance condition. Based on applied method results, the horn was machined, proving real natural frequencies very close to those outcomes from FEM modelling. [ABSTRACT FROM AUTHOR]

The paper main aim is to document and analyze the environmental impact of some machine tools working phase, as well as to identify potential for environmental improvement. The work focuses on two case studies, one for conventional machining, e.g. milling machining and the other one for a nonconventional machining, e.g. electrical discharge machining (EDM), using CO2PE! methodology. This comprises two approaches, the screening one, which provides a first insight into the unit process and indepth one, in which all relevant process inputs and outputs are measured and analyzed in detail. [ABSTRACT FROM AUTHOR]

The paper deals with the process of computer aided machining (CAM) of ultrasonic horn, included in an ultrasonic chain used at ultrasonic assistance of electrical discharge machining (EDM). The assistance with ultrasonics of EDM process (EDM+US) leads to technological parameters improvement in terms of machining rate, volumetric relative wear and surface quality. Nevertheless, the lack of flexibility of EDM+US technology due to time consuming for resonance condition achievement, supposing several iterative stage, is an important disadvantage. CNC machining of ultrasonic horn is a strong support for amelioration of this drawback. The paper presents a CAM application developed in AutoLISP under AutoCAD used for accurate fabrication of ultrasonic horn on CNC lathe, easily covering the needed iterations to equalize the own frequencies of transducer and horn. [ABSTRACT FROM AUTHOR]

The paper deals with researches aiming at increase of technological performances at micro-electrical discharge machining aided by longitudinal ultrasonic oscillations of electrode-tool (μEDM+US). Some essential issues of complex phenomenology of μEDM+US, experimental results obtained so far, and some appropriate strategies for material removal process are presented. Finite Element Method (FEM) applied at μEDM+US in connection with strategies to be followed is approached. Patented solutions for equipment dedicated to μEDM+US used at WEDM, microslots, and deep microslots machining are presented. [ABSTRACT FROM AUTHOR]