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Mohammed El Adnani Krabch, Abdelouahed Chetaine, Abdelati Nourreddine, Fatim Zohra Er-Radi and Laila Baddouh

Abstract

The aim of this study was to investigate the impact of heterogeneity on the dose calculation for two algorithms implemented in the TPS “Analytical Anisotropic Algorithm (AAA) and Acuros XB” and validated the use of Acuros XB algorithm in clinical routine. First, we compare the dose calculated by these algorithms and the dose measured at the given point P, which is found after heterogeneity insert. Second, we extend our work on clinical cases that present a complex heterogeneity. By evaluating the impact of the choice of the algorithm on the dose coverage of the tumor, and the dose received by the organs at risk for 20 patients affected by lung cancer.

The result of our phantom study showed a good agreement with several studies that showed the superiority of the Acuros XB over the AAA in predicting dose when it concerns heterogeneous media. The treatment plans for 20 lung cancers were calculated by two algorithms AAA and Acuros XB, the results show a statistical significant difference between algorithms for Homogeneity Index and the maximum dose of planning target volume (HI: 0.11±0.01 vs 0.05±0.01 p = 0.04; Dmax: 69.30±3.12 vs 68.51±2.64 p = 0.02). Instead, no statistically significant difference was observed for conformity index CI and mean dose (CI: 0.98±0.18 vs 0.99±0.14 p = 0.33; Dmean: 66.3±0.65 vs 66.10 ±0.61 p = 0.54). For organs at risk, the maximum dose for spinal cord, mean dose and D37 % of lung minus GTV (dose receiving 37% of lung volume) were found to be lower for AAA plans than Acuros XB and the differences were statistically significant (p<0.05). For the heart D33% and D67% were found to be higher for AAA plans than Acuros XB and the differences were statistically significant (p<0.05), but No difference was observed for D100% of the heart.

The use of the AXB algorithm is suitable in the case of presence of heterogeneity, because it allows to have a better accuracy close to the Monte Carlo calculation.

Open access

F. Ulloa, L García-Santander, D. Carrizo and C. Hurtado

Abstract

The efficient use of energy and its implementation in domestic automation systems is an essential requirement in Smart Cities. However, this requires appropriate measurement devices and an M2M control-communication alternative that offers real-time visualization of the information. This article proposes a prototype of the home electric power consumption management platform, as an advance in generating a model for future Smart Grid. Therefore, the research implements smart socket devices and a coordinator of the communication of a home area network between these measuring devices to have an intelligent control of electric power. As a result, real-time data of the defined electrical parameters have been obtained. This information has been stored in the Internet cloud, also allowing remotely programming and controlling these measurement devices. The present research contributes to generating a profile of total load consumption for residential users and allowing them to know and compare their real consumption with what was reported by the distributors.

Open access

A. Rassõlkin, A. Kallaste, S. Orlova, L. Gevorkov, T. Vaimann and A. Belahcen

Abstract

The paper discusses the current developments in the recycling of electrical machines. The main attention is devoted to three types of motors: synchronous reluctance motor, permanent magnet assisted synchronous reluctance motor, and induction motor. Base materials of such electrical machines are also described in the paper. Rare-earth permanent magnets used in electrical machines are review separately. Moreover, the paper considers the features of the disassembly and recycling options.

Open access

E. Pudzis, A. Adlers, I. Pukite, S. Geipele and N. Zeltins

Abstract

Recognising the fact that economic realities change the world faster than global politics, in 2010 the European Commission approved the strategy for smart, sustainable and inclusive growth, called EUROPE 2020, in order to promote greater economic independence and achieve a more sustainable future. The strategy puts forward three mutually reinforcing priorities: (P1) Smart Growth: developing an economy based on knowledge and innovation; (P2) Sustainable Growth: Promoting a more resource efficient, greener and more competitive economy; (P3) Inclusive Growth: Promoting a high-employment economy delivering social and territorial cohesion.

In the context of EUROPE 2020, the Smart Specialisation Strategy in Latvia (RIS3) has been set up and introduced as a strategic document for the development of support mechanisms of high value-added economic growth, including the maritime technology sector.

The present study explores the mechanisms for the introduction of Blue Growth and RIS3 Strategies, which should be used to develop the maritime technology industry by assessing the efficiency of these mechanisms. Thus, the study addresses the issues of the implementation of modern technologies in the coastal municipalities and planning regions of Latvia.

Open access

S. Geipele, E. Pudzis, J. Uzulens, I. Geipele and N. Zeltins

Abstract

The present scientific paper is the fourth part and continuation of the in-depth scientific study of the developed system of engineering economic indicators, where the authors obtain results from the scientific research presented in a series of works on the development of the nanotechnologies and advanced materials industry in science and entrepreneurship in Latvia. Part Four determines the essential legal indicators of the development of nano-field at the macro, micro, and meso development levels of the economic environment in Latvia. The paper provides the interaction of new identified indicators of nano-field in terms of further scientific and practical activities. Latvia is analysed in comparison with other countries in the world.

Open access

I. Rankis and G. Zaleskis

Abstract

The paper presents results of analysis of a possible solution for enhancement of frequency converter (FC) AC supply power parameters. The method proposed is based on switched stabilisation of DC current of FC front-end rectifier unit. Such stabilisation allows obtaining rather good AC supply power parameters, i.e., its power factor and total harmonics distortion (THD) indicator for phase current. The paper also demonstrates a possible realisation scheme, a simplified mathematical description of processes in the scheme, as well as methods for consideration of its parameters, accounting the rated power of FC and the appointed level of the rectifier DC current continuity ratio. The results of computer simulation, to a great extent, testify a possible enhancement level.

Open access

N. Bulaha and J. Rudzitis

Abstract

In the scientific research, calculations of roughness parameters are carried out, with the aim of comparing measured values of roughness parameters with the calculated ones by normal random field equations. First of all, roughness measurement experiments for surfaces with irregular roughness are carried out to determine the roughness parameters and the ordinate distribution histograms using modern measuring equipment Taylor Hobson Talysurf Intra 50. Using the obtained experimental data, Pearson criterion calculations are made in order to check the compliance of surface ordinate distribution function to normal Gaussian distribution law. The obtained results showed that for all investigated samples the surface ordinate distribution function complies with normal Gaussian distribution law. The next step is the calculation of several 3D roughness parameters (from the standard ISO 25178-2). According to the obtained results it is concluded that the calculated values of surface roughness parameters Sa, Sp, Spc, Sdq, Sdr are quite close to the values obtained by measuring equipment Taylor Hobson. The acquired formulas may be applicable for determination of 3D roughness parameters.

Open access

S. Orlova, V. Pugachov and R. Otankis

Abstract

The research is devoted to the investigation of NdFeB permanent magnet (PM) based synchronous generators with non-overlapping concentrated windings. The rotor of such a generator has 10 pole pairs (PMs), which is dictated by the nominal voltage frequency (f=50 Hz) and the rotational speed (n=300 RPM). Comparison is made for four generators with three-phase winding coils and stator tooth numbers 18, 21, 24 and 27.

Open access

M. Muthtamilselvan and S. Sureshkumar

Abstract

This paper is intended to investigate the effects of an inclined magnetic field on the mixed convection flow in a lid-driven porous enclosure filled with nanofluid. Both the left and right vertical walls of the cavity are thermally insulated while the bottom and top horizontal walls are maintained at constant but different temperatures. The governing equations are solved numerically by using finite volume method on a uniformly staggered grid system. The computational results are obtained for various combinations of Richardson number, Darcy number, Hartmann number, inclination angle of magnetic field, and solid volume fraction. It is found that the presence of magnetic field deteriorates the fluid flow, which leads to a significant reduction in the overall heat transfer rate. The inclination angle of magnetic field plays a major role in controlling the magnetic field strength and the overall heat transfer rate is enhanced with the increase of inclination angle of magnetic field. Adding the nanoparticles in the base fluid significantly increases the overall heat transfer rate in the porous medium whether the magnetic field is considered or not.

Open access

O. Golevych, O. Pyvovar and P. Dumenko

Abstract

Areas of optimal amplitudes and minimal spectral unevenness of Rucklidge chaotic signals with better correlation abilities are demonstrated in the present research. A model of chaotic synchronization and information transmission system is implemented. The effect of the synchronization feedback coefficient and signal-to-noise ratio on the systems noise immunity is shown.