49 research outputs found
Volatile Compounds as Markers of Terroir and Winemaking Practices in Fetească Albă Wines of Romania
No full textThis study evaluates the influence of terroir on the physico-chemical characteristics and aromatic profiles of Fetească albă wines from five major Romanian wine regions. By analysing key factors such as soil types, climatic conditions, and winemaking techniques, the study aims to understand their impact on wine composition and quality. The study includes the analysis of superior alcohols, fatty acids, esters, carbonyl compounds, terpenes, and 4-mercapto-4-methylpentan-2-one, which are essential in defining the aromatic complexity of the wines. The results show how fermentation conditions, temperature control, microbial activity, and oxidative exposure contribute to the evolution of these compounds, influencing the sensory profiles. Significant differences in compound concentrations were observed across the regions, with wines from Dealu Mare and Murfatlar exhibiting high ester content and aromatic complexity, while those from Dealul Bujorului and Panciu showed elevated volatile acids and aromatic alcohols, suggesting distinct fermentation dynamics. Climatic factors, such as temperature and precipitation, played a crucial role in shaping the volatile composition, with elevated temperatures in 2021 enhancing ester formation and higher alcohol production. This study demonstrates the critical role of terroir and winemaking practices in shaping the aromatic and sensory characteristics of Romanian Fetească albă wines
Analysis and design of a two-speed single-phase induction motor with 2 and 18 pole special windings
No full textThe motor presented employs multiple independent windings for operation with two very different pole numbers. The 18-pole field is produced with a symmetrical three-phase winding connected in a Steinmetz arrangement to a single-phase supply. A unified analysis method has been developed and used to demonstrate the equivalence of a Steinmetz delta or star connection with a main and auxiliary winding of a single-phase motor. The method has been experimentally validated and also included are some specific motor design considerations
Computation of core losses in electrical machines using improved models for laminated steel
No full textTwo new models for specific power losses in cold-rolled motor lamination steel are described together with procedures for coefficient identification from standard multifrequency Epstein or single sheet tests. The eddy-current and hysteresis loss coefficients of the improved models are dependent on induction (flux density) and/or frequency, and the errors are substantially lower than those of conventional models over a very wide range of sinusoidal excitation, from 20 Hz to 2 kHz and from 0.05 up to 2 T. The model that considers the coefficients to be variable, with the exception of the hysteresis loss power coefficient that has a constant value of 2, is superior in terms of applicability and phenomenological support. Also included are a comparative study of the material models on three samples of typical steel, mathematical formulations for the extension from the frequency to the time domain, and examples of validation from electrical machine studies
The Cuntz algebra Q_N and C*-algebras of product systems
No full textWe consider a product system over the multiplicative group semigroup N^x of Hilbert bimodules which is implicit in work of S. Yamashita and of the second named author. We prove directly, using universal properties, that the associated Nica-Toeplitz algebra is an extension of the C*-algebra Q_N introduced recently by Cuntz
The Cuntz algebra Q_N and C*-algebras of product systems
No full textWe consider a product system over the multiplicative group semigroup N^x of Hilbert bimodules which is implicit in work of S. Yamashita and of the second named author. We prove directly, using universal properties, that the associated Nica-Toeplitz algebra is an extension of the C*-algebra Q_N introduced recently by Cuntz
INTERNATIONAL TRADE OF ROMANIA IN THE CONTEXT OF ITS LOW ECONOMIC POTENTIAL
No full textThe study provides a view on Romanian economy in terms of its competitiveness and potential for sustaining an efficient foreign trade. After reviewing literature and the reports of prestigious institutions and bodies in the area, the author presents several elements providing an accurate image on current quantitative and qualitative parameters of Romanian foreign trade, the internal and foreign processes influencing it and its main trends. The theoretical, legislative and institutional background of the paper was developed earlier by the author in his monograph - "The legal and financial regime applicable to international foreign trade" published in 2008 by ArtPress Publishing House after Romania joined the European Union. In this study, however, the focus is placed on major changes that have occurred in Romania’s foreign trade after it joined the European structures
High amplitude oscillating magnetic field applicator for remote magnetic nanoparticle detection
No full text
Static Analysis of the Structure Type Tank Thermally
No full textThis paper consider finite element analysis for structural analysis of a tank under thermal loadings. Geometric modeling is done in CATIA and for finite element analysis the author used FEA module in Catia. The aim is to determine von Mises stress field, deformed mesh and thermal loadings
Special Issue “Audit and Financial Control Tools Aimed at Ensuring the Sustainable Performance of Organizations”
No full textThrough this editorial, the author aims to present the main landmarks related to the scientific contributions that can be found in the special issue dedicated to the topic “Audit and Financial Control Tools Aimed at Ensuring the Sustainable Performance of Organizations” [...
