[en] The aim of this article was to present the studies of radiological level of some commercial dairy products in Mazovian, Kuyavian-Pomeranian and Lublin regions. They were carried out for 27 commercial dairy products such as two specimens of lean cottage cheese, three specimens of cottage cheese containing a limited percentage of fat, three specimens of fat cottage cheese, three specimens of milk containing 3.2% of fat, three specimens of milk containing 2.0% of fat, two specimens of sour cream containing 12% of fat, three specimens of sour cream containing 18% of fat, one specimen of 30% whipping cream, two specimens of homogenized (strawberry and vanilla) cheese, three specimens of hard rennet cheese, one specimen of powdered milk, one specimen of goat milk. For the given commercial dairy products there were calculated effective doses (?Sv) obtained after consumption of 1 kg contaminated product for different age groups. (author)

[en] Highlights: • Effective elastic constants of GFRT pipes are studied by theoretical method. • The results from theoretical method, 3D and simplified model agree well. • Effective elastic constants are only related with the winding angle and the volume fractions. • There is a corresponding winding angle for optimal properties in different directions. -- Abstract: In this paper, a theoretical method, a 3D model and a simplified model are proposed to investigate the effective elastic constants of the glass-fibre reinforced thermoplastic (GFRT) pipes. The effects of the layer thickness, winding angle and reinforced layer volume fractions of the GFRT pipes on the effective elastic constants are discussed. The results show that the proposed simplified model can predict the effective elastic constants in three directions very well. The effective elastic constants developed by theoretical method and simulation have a good agreement, and they are only related with the winding angle and the reinforced layer volume fractions. With the increase of the winding angle, $E_{\text{φ}}$ decreases, while $E_{\text{z}}$ and ${\nu }_{\text{ρφ}}$ gradually increase. The pipes with winding angle of $[\pm {45}^{\circ }]$ give peaks of $E_{\text{ρ}}$ and $G_{\text{zφ}}$. The ${\nu }_{\text{zφ}}$ and ${\nu }_{\text{zρ}}$reach maximum and minimum values, respectively, when winding angle is $[\pm {60}^{\circ }]$. There is a corresponding winding angle for optimal properties in different directions.

[en] We present a model based on a two-scale asymptotic analysis for resonant arrays of the Helmholtz type, with resonators open at a single extremity (standard resonators) or open at both extremities (double-sided resonators). The effective behaviour of such arrays is that of a homogeneous anisotropic slab replacing the cavity region, associated with transmission, or jump, conditions for the acoustic pressure and for the normal velocity across the region of the necks. The coefficients entering in the effective wave equation are simply related to the fraction of air in the periodic cell of the array. Those entering in the jump conditions are related to near field effects in the vicinity of the necks and they encapsulate the effects of their geometry. The effective problem, which accounts for the coupling of the resonators with the surrounding air, is written in the time domain which allows us to question the equation of energy conservation. This is of practical importance if the numerical implementations of the effective problem in the time domain is sought. (authors)

[en] Published in summary form only

[en] Complete text of publication follows. The new devices have been developed for laser beams homogenizing in the focal spot - multi-component lens raster and raster with the edges smoothing phase mask. The envelope non-uniformity of < 3-5% at energy concentration up to 60% was achieved for beams having the initial non-uniformity in the near field of approximately 30% and divergence ≤ 10^-4 radians. Investigation into the temporary-spatial smoothing with the use of low-density foams with the density less than the critical one is still in progress. Experiments on the foams with the density of 1-2.3 mg/cm³, thickness of 100-200 μm, and the cells' sizes up to the tens of micrometers were carried out with the radiation wavelength of 0.657 μm. The RMS non-uniformity < 5% has been found for the beam passed through the foam. The non-uniformity is evenly distributed over the spatial frequency spectrum. The induced divergence of radiation is measured to be 0.35 radian. The frequency of the rearranged speckled field of about 2 THz was obtained. The beam smoothing was recorded from the start of pulse of radiation, had the duration up to 1 ns, and the width of the radiation spectrum was about 30 A. The work was performed in part under the sponsorship of the RFFI (grants No. 09-02-12157-ofi-m and No. 09-02-97095-r-povolzh'ye-a) and grant of the President of the RF to leading scientific schools No. 65192.2010.2.

[en] We present a homogenization model for a single row of locally resonant inclusions. The resonances, of the Mie type, result from a high contrast in the shear modulus between the inclusions and the elastic matrix. The presented homogenization model is based on a matched asymptotic expansion technique; it slightly differs from the classical homogenization which applies for thick arrays with many rows of inclusions (and thick means large compared to the wavelength in the matrix). Instead of the effective bulk parameters found in the classical homogenization, we end up with interface parameters entering in jump conditions for the displacement and for the normal stress; among these parameters, one is frequency dependent and encapsulates the resonant behavior of the inclusions. Our homogenized model is validated by comparison with results of full wave calculations. It is shown to be efficient in the low frequency domain and accurately describes the effects of the losses in the soft inclusions. (authors)

[en] [Background] The new generation of pin-by-pin calculation method has gradually become the state-of-the-art approaches along with the improvement of computer technology and the development of core design. The difference between the pin-by-pin calculation and the traditional two-step scheme leads to the homogenization technique difficult to implement. [Purpose] This study aims to evaluate super homogenization techniques for pin-by-pin core calculation with emphasis on equivalent homogenization constants. [Methods] Super homogenization method was used as one of the main homogenization techniques of pin-by-pin calculation. For fuel assembly, the traditional super homogenization method was employed to generate the group constants. For reflector assembly with neutron leakage, the super homogenization method related to space leakage was applied to the generation of equivalent homogenization constant including super homogenization factor. [Results] Based on the threedimensional C5G7 benchmark, the application performance of the super homogenization method in pin-by-pin calculation is evaluated. The eigen-value relative error of pin-by-pin calculation is -0.0016, assembly-power and pin-power relative errors are less than 5.5%. [Conclusions] Numerical results showed that the pin-by-pin calculations have the higher accuracy than the assembly-homogenized results. (authors)

No abstract available

[en] We propose an investigation combining numerical and analytical tools to estimate the ageing viscoelastic properties of cement-based materials within a multi-scale framework.With analytical homogenization the properties at the cement paste and mortar scales are estimated by a combination of Generalized Self-Consistent (GSC) and Mori-Tanaka (MT) schemes. With numerical homogenization the effective properties at the concrete scale are estimated. Numerical homogenization has the advantage of allowing assessing local information and to study more complex geometries. This combined strategy constitutes a promising tool to investigate how different mechanisms leading to ageing at the hydrated products scale, as well as other features of cement-based materials such as the Interfacial Transition Zone (ITZ), affect the viscoelastic behaviour at superior scales. In this context, we study the solidification of non-ageing constituents as the mechanisms leading to the ageing behaviour combined or not with a space-filling process in C-S-H. Relaxation and creep results are presented. (authors)

[en] This work deals with the homogenization of functionals with linear growth in the context of $\mathcal{A}$-quasiconvexity. A representation theorem is proved, where the new integrand function is obtained by solving a cell problem where the coupling between homogenization and the $\mathcal{A}$-free condition plays a crucial role. This result extends some previous work to the linear case, thus allowing for concentration effects.