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The human femur shows a high capacity to withstand external stresses and it is due to the mass distribution, morphology, and orthotropic behaviors of trabecular and cortical bone. Faithful modeling of the femur accounting for bone distribution and material orthotropic behavior is presented. The use of biofidel model is aimed to develop an “in silico” tool that could enable the valuation of biomechanics modification induced by the alteration of the structural and morphological characteristic in prothesized bones. Moreover, a faithful model assists us in the development of new design criteria for innovative prosthetic systems that, following the isostatic loading lines, could restore the physiological and natural stress and strains distribution. In this study a biofidel femur Finite Element Model (FEM) has been developed from Computerized Tomography (CT) scans using specific combination of software’s to correctly represent bone physiology and structural behavior. Proper identification of trabecular bone arrangement and distribution in the proximal diaphysis enabled modeling and definition of material properties. The faithful femur model proposed allows us to correctly account for non-isotropic properties to the proximal end explaining the critical structural role played by trabecular bone that should be taken into account in the design of new innovative prosthetic system.

A method for PET mechanical properties enhancement by reactive blending with HBA/HNA Liquid Crystalline Polymers for in situ highly fibrillar composites preparation is presented. LCP/PET blends were reactive extruded in presence of Pyromellitic Di-Anhydride (PMDA) and then characterized by Differential Scanning Calorimetry, Thermally Stimulated Currents and tensile mechanical properties. The formation of specific macromolecular structures, where the PET, the LCP and the reactive additive are involved, has been hypothesized in the reactively extruded blends from TSC analysis evidences. The use of a reactive additive improved the matrix LCP compatibilization and adhesion as indicated by the SEM analysis and mechanical testing. Moderate amounts of LCP in the PET (0.5 and 5%) and small amounts of thermo-active and reactive compatibilizer in the blend (0.3%) were found to significantly improve LCP melt dispersion, melts shear transfer and LCP fibril formation and adhesion. Blends of PET and LCP containing the compatibilizer favored the formation of a well dispersed and homogeneous fibrillar phase whose particle size distribution did not show great coarsening and coalescence leading to significant elastic properties improvements from 0.8 for not compatibilized to 3.1 GPa for compatibilized 0.5% LCP loaded PET blends that was even higher than those expected from ordinary theoretical calculation. This unexpected improvement was probably due to the presence of two distinct phases’ supra-molecular structures involving PET-LCP and PMDA.

The development and diversification of machines and mechanisms with applications in all fields require new scientific researches for the systematization and improvement of existing mechanical systems by creating new mechanisms adapted to modern requirements, which involve increasingly complex topological structures. The modern industry, the practice of designing and building machinery is increasingly based on the results of scientific and applied research. Each industrial achievement has backed theoretical and experimental computer-assisted research, which solves increasingly complex problems with advanced computing programs using an increasingly specialized software. The robotization of technological processes determines and influences the emergence of new industries, applications under special environmental conditions, the approach of new types of technological operations, manipulation of objects in the alien space, teleoperators in the top disciplines like medicine, robots covering a whole field greater service provision in our modern, computerized society. Movable, robotic, mechatronic mechanical systems have entered nearly all industrial spheres. Today, we can no longer conceive of industrial production without these extremely useful systems. They are still said to steal from people's jobs. Even so, it should be made clear that these systems create value, work in difficult, repetitive, non-pausing, high-quality work, without getting tired, without getting sick, without salary and producing value who are paid and people left without jobs, so that they can work elsewhere in more pleasant, more advantageous conditions, with the necessary breaks. Mechanical systems in motion type parallel structures are solid, fast and accurate. Between mobile systems parallel the best known and used system is that of a Stewart platforms, as being and the oldest system, quickly, solid and accurate. The paper presents a few main elements of the Stewart platforms. In the case where a motto element consists of a structure composed of two elements in a relative movement from the point of view of the train of propulsion and especially in the dynamic calculations, it is more convenient to represent the motto element as a single moving item. The paper presents an exact, original analytical geometry method for determining the kinematic and dynamic parameters of a parallel mobile structure. Compared with other methods already known, the presented method has the great advantage of being an exact analytical method of calculation and not one iterative-approximately.

The today main challenge to protect the environment through the development of new and more efficient transportation systems is presented. The absolutely necessary goods distribution and human transfers are polluting and damaging the environment and new solution should be envisaged; the conflicting strategies to adopt new types of environment friendly transportation while maintaining operative the more economically convenient, but largely polluting, already existing machines are discussed and compared. Shipment is an activity that is occurring since the existence of man who felt the need to find ways for him and his goods transportation. Physical human body limits have led to the discovery of a variety of systems for a continuous transportation evolution. This work analyzes the new environment friendly technologies that have been recently developed or that could be further implemented in the next near future. In view of the constantly improvement of the quality of transportation to be carried out, the transportation sector has various aspects that need to be investigated. Passenger comfort, flexible design, maximum interior space, safety and greater range are main features that improve transportation efficiency while making these technologies more familiar and accepted by consumers. Avoiding any excessive generalization, the three major transportation interacting branches, namely, infrastructures, vehicles and management have been reviewed. Such a complex system needed the application of an evolutionary design approach considering renewable energy sources for Hydrogen production as well as electric or internal combustion engines. The overall transportation network and related terminals have been involved as infrastructures, while all aspects of design, construction, operation diagnostics and traffic interactions have been considered for the vehicles. Finally, the management of the engineering responsibilities chain to ensure quality, safety and environmental impact of the transportation systems has been assessed.

Over time it has advanced the idea that the achievement of a hot nuclear reaction can require tens or hundreds of millions of degrees. Precise calculations clearly indicate a much higher temperature. At least 10 million degrees are necessary for 1 keV in thermonuclear reaction. At 400 keV it needs a temperature of 4000 million degrees to occur the hot fusion reaction. Hot fusion needs a temperature of about 4000 million degrees, or 4 billion degrees if we believe in the calculations the radius of deuterium static. If we believe in the calculations the radius of the real, dynamic deuterium, in movement, the temperature required to achieve the warm fusion reaction increases still 10000 times, reaching a value of 40 trillions degrees. Unfortunately, this clarification does not bring us closer to the realization of the hot fusion reaction, but on the contrary, us away from the day when we will be able to achieve it. Today we have only made 150 million degrees. A huge problem is even the achievement of such temperatures. For these reasons we are entitled to think up next following, namely achieving the cold fusion. Authors propose to bomb the fuel with accelerated Deuterium nuclei.