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Violin studies can be classified into two main types: psychoacoustic studies, which are based on the artistic perception of audibility by violinists and vibro-acoustic studies, which are based on the spectral analysis of the vibrations and sounds produced by the instruments. The paper presents the acoustic analysis of violins by means of specialized software, their main acoustic characteristics being extracted in the form of frequency spectrum, spectrograms, specific modes and number of harmonics. These results were compared with the results of the opinion poll among musicians regarding the acoustic qualities of violins, based on musical auditions. The results highlighted the fact that the acoustic analysis technique cannot detect in totality the psycho-acoustic effects of musical sounds, therefore the establishment of the acoustic quality of the instruments on objective foundations, since the personal touch of an instrumental artist aims at the approach and articulation of the musical discourse, in a complex manner, combined with the interpretation of forms and styles.

The paper presents the interdisciplinary approach of two fields - the artistic (musical) and technical (forestry engineering, wood processing engineering, mechanical and physical engineering) apparently opposite but which can be happily exploited for both parties. Thus, we can speak of a new paradigm of education through which art can combine with the technical sciences for the benefit of all. The aim of the paper is to present experimental methods in mechanical and acoustic evaluation of violins from engineering and artistic perspectives. The presented results are part of a larger study carried out within an experimental demonstration research project.

This work is focusing on electrospinning polyethylene oxide (PEO) with incorporated barium ferrite nano-particles (BaFe) and the characterization of the magnetic properties of the obtained composites fibers. The barium ferrite powders used belong to a group of ferrites with hexagonal crystal structure. PEO has low toxicity, is water soluble, and is available in a variety of molecular weights of which 600.000 g/mol was used in this study. Following successful electrospinning of magnetic composite fibers, we have selected two samples, denoted as S1 and S2, for further investigation. The process parameters corresponding to the production of S1 and S2 differ only by the needle tip-to-collector distance which is larger for S2 (70 mm as compared to 50 mm). SEM images and fiber diameter distributions reveal that, as previously shown for pure PEO electrospun fibers, the average fiber diameter is decreasing with decreasing tip-collector distance. In addition, the distribution of the fiber diameters for the S1 sample is wider than the one for S2. This is indicative of a less controlled electrospinning process in the case of the S1 sample. Magnetic measurements on composite fibers reveal an expected ferrimagnetic behavior and no major differences between the magnetic properties of S1 and S2.

Recent studies have showed that the microstructure and mechanical properties of A356 alloy can be significantly improved when ultrasonic cavitation and solidification processing is used. This is because during the fabrication of A356 castings, ultrasonic cavitation processing plays an important role in degassing and refining the as-cast microstructure. In the present study, A356 alloy and Al2O3/SiC nanoparticles are used as the matrix alloy and the reinforcements, respectively. Nanoparticles are injected into the molten alloy and dispersed by ultrasonic cavitation. Ultrasonic cavitation was also applied during solidification of these nanocomposites. The microstructure and nanoparticle distribution of the cast samples have been investigated in detail. The current experimental results indicated that ultrasonic cavitation during solidification will greatly improve the microstructure of the samples. Al2O3 and SiC nanoparticle reinforced nanocomposites have different nanoparticle distributions in the matrix.

In this paper we analyze the way of choosing the technical solutions concerning the supply of thermal energyfor residential groups of buildings, using the Multicriterial Ordinal Ranking Model, the Relative Distance Comparisonmodel in relation with the maximum performance and the Relative Distance Comparison model in relation with theaverage performance. The paper ends with the presentation of the numerical results and a few conclusions. Themodels proposed may be used in practice in case of feasibility studies, for master degree theses as well as for Ph.D.theses.

Modelling and simulation is an important aspect in robotic field. Knowing of the workspace is very important to the operation of manipulators arm. This paper investigates operational performance of space manipulator arm destined for industrial manufacturing, by defining and analyzing their workspace and manipulability measure. The authors show that manipulator arm developing requires the consideration of more efficient dynamic models and use of dedicated processing techniques such as Autodesk-Inventor 9, MATLAB, WorkSpace software.

A conceptual model of the industrial design process for isolation against vibrations is proposed and described. This model can be used to design products subject to functional, manufacturing, ergonomic, aesthetic constraints. In this paper, the main stages of the model, such as component organization, conception shape, product detailing and graphical design are discussed. The work has confirmed the validity of proposed model for rapid generation of aesthetic preliminary product designs using the virtual prototyping technique, by one of its main component that is conceptual product design.

Neurofibromatosis is a genetic disorder arising de novo or with an autosomal dominant transmission that typically presents either at birth or in early childhood, manifesting through distinctive clinical features such as multiple café-au-lait spots, benign tumors in the skin, bone enlargement, and deformities. This literature review aims to resume the spectrum of maternal and fetal complications encountered in pregnant women with neurofibromatosis type 1 (NF1). Thorough research was conducted on databases such as Web of Science, PubMed, Science Direct, Google Scholar, and Wiley Online Library. This review includes 48 case reports, original studies, and reviews on NF1 in pregnancy. The research on the interlink between NF1 and fertility and its influence on human-assisted reproduction techniques is limited. Preimplantation testing (by in vitro fertilization) and prenatal diagnosis (by chorionic villus sampling or amniocentesis) are available to detect affected fetuses. However, genotype–phenotype correlation is difficult to predict. Preconceptional planning and targeted investigations are crucial in understanding the extent of maternal disease. Although in some cases lesions can evolve rapidly during pregnancy, most pregnancies and births in NF1 go well with careful planning. There is a higher incidence of pheochromocytomas and pre-eclampsia, vascular rupture, and cardio-respiratory issues. Anesthesia at birth is a challenge in most cases, and before offering spinal anesthesia, imaging tests should be performed to characterize spinal lesions. General anesthesia may also be challenging when the disease affects the face, neck, upper spine, or airways. Birth-related difficulties may arise because of large neurofibromas located at the level of skin incision or birth canal; uterine atony may be expected if there are uterine lesions. Some complications can develop in postpartum, and affected women should be carefully followed even after pregnancy. Fetal risks include preterm birth (spontaneous or iatrogenic), growth restriction and developmental issues, birth complications, cardiovascular risk, and fetal/neonatal demise. Pregnancies in women with NF1 should be regarded as high-risk and followed in a multidisciplinary fashion. Careful assessment of lesions is of utmost importance before and during pregnancy for anticipating potential maternal risks and before birth to plan anesthesia and delivery. [ABSTRACT FROM AUTHOR]

The rheological modeling of soil–drum interaction in the vibratory compaction process is a complex process. This paper aims to describe the behavior of soil–drum interaction through lumped parameter modeling. The amplitude of the vertical motion is evaluated for dynamic conditions using the rheological models (generalized and advanced Kelvin–Voigt-based models) and compared with the experimental results obtained from weakly cohesive soil compaction. Different modeling approaches are considered, and the results reveal that the properties of the soil as input play a vital role in the accuracy of the modeling. [ABSTRACT FROM AUTHOR]