Asymptotic equivalence of impulsive differential equations in a Banach space

By means of Schauder's fixed point theorem sufficient conditions for asymptotic equivalence of impulsive equations in a Banach space are found

Novel superconducting phases of Tl-based compounds

Several new superconducting phases of the Tl-based compounds were prepared. Structural studies revealed cell lengths of 31.9 A and longer. Properties of Ce-containing compounds are also discussed

On a Second Critical Point in the First Order Metal - Insulator Transitions

For the first order Metal Insulator Transitions we show that together with the d.c conductance zero there is a second critical point, where the dielectric constant becomes zero and further turns negative. At this point the metallic reflectivity sharply increases. The two points can be separated by a Phase Separation State in a 3D disordered system, but may tend to merge in 2D. For illustration we evaluate the dielectric function in a simple effective medium approximation and show that at the second point it turns negative. We reproduce the experimental data on a typical Mott insulator like MnO, demonstrating the presence of the two points clearly. We discuss other experiments for studies of the phase separation state and a similar phase separation in superconductors with insulating inclusions.Comment: 4pages, 2 figure

Lake-atmosphere interactions at Alqueva reservoir : a case study in the summer of 2014

The study of lake-atmosphere interactions was the main purpose of a 2014 summer experiment at Alqueva reservoir in Portugal. Near-surface fluxes of momentum, heat and mass [water vapour (H2O) and carbon dioxide (CO2)] were obtained with the new Campbell Scientific's IRGASON Integrated Open-Path CO2/H2O Gas Analyser and 3D Sonic Anemometer between 2 June and 2 October. On average, the reservoir was releasing energy in the form of sensible and latent heat flux during the study period. At the end of the 75 d, the total evaporation was estimated as 490.26 mm. A high correlation was found between the latent heat flux and the wind speed (R = 0.97). The temperature gradient between air and water was positive between 12 and 21 UTC, causing a negative sensible heat flux, and negative during the rest of the day, triggering a positive sensible heat flux. The reservoir acted as a sink of atmospheric CO2 with an average rate of -0.026 mg m(-2) s(-1). However, at a daily scale we found an unexpected uptake between 0 and 9 UTC and almost null flux between 13 and 19 UTC. Potential reasons for this result are further discussed. The net radiation was recorded for the same period and water column heat storage was estimated using water temperature profiles. The energy balance closure for the analysed period was 81%. In-water solar spectral downwelling irradiance profiles were measured with a new device allowing measurements independent of the solar zenith angle, which enabled the computation of the attenuation coefficient of light in the water column. The average attenuation coefficient for the photosynthetically active radiation spectral region varied from 0.849 +/- 0.025 m(-1) on 30 July to 1.459 +/- 0.007 m(-1) on 25 September.Peer reviewe

A multi-input UV-VIS airborne GASCOD/A4r spectroradiometer for the validation of satellite remote sensing measurements

The present paper describes a UV-VIS spectroradiometer named GASCOD/A4r developed at ISAC-CNR for remote sensing measurements aboard stratospheric M55-Geophysica aircraft, flying up to 21 km. Obtained experimental data are used for retrieving of NO2, O3 and of other minor gases atmospheric content, applying the DOAS (Differential Optical Absorption Spectroscopy) method. UV actinic flux and J(NO2) are also derived. All these parameters are used for satellite data validation tasks. The specific results obtained during dedicated aircraft missions in different geographical areas have already been utilized for ENVISAT validation

Herb Stem Cutter -Design and Research

Abstract IVANOV, D., G. KOSTADINOV, T. MITOVA and I. DIMITROV, 2006. Herb stem cutter -design and research. Bulg. J. Agric. Sci., The article presents the results of investigations on a herb stem cutting machine. Investigations were performed as a series of controlled single-factor experiments. The basic target functions of the study were as follows: drive's absorbed power of the machine (kW); specific energy consumption (kWh/t) and average cutting length (mm). The levels of controlled trial factors were as follows: machine load capacity with herb stem mass: Q = 0.5; 1 and 1.5 kg/s and feeding velocity of stem mass to the cutting drum: V = 2.0; 2.4 and 2.8 m/s. Here are the factors, maintained at stable levels: cutting drum peripheral velocity -25 m/s at rotation frequency of 1176 min -1 ; cutting drum working width -Β=0.558 mm; cutting drum diameter D=0.406 m; number of blades z=6; blade thickness b=10 mm; blade sharpening angle β=34°; inclination of blades' edges to the counteredge α=15°; front cutting angle ϕ=50°; gap between blade and counterblade edges ∆=0.5 mm; sharpening angle of the counterblade β 1 =90° and sharpness of counterblade cutting edge δ=0.2 mm. The correlation between the variation of drive's absorbed power for startup of the cutting drum, specific energy consumption and average cutting length, on the one hand, and the variation of controlled factors, on the other, was established. The respective adequate regression equations were simulated, describing the herb stem cutting processes with specific accuracy

Optimal Cutting Problem

One of the tasks of the Construction office of company STOBET Ltd is to create large sheets of paper containing a lot of objects describing a building construction as tables, charts, drawings, etc. For this reason it is necessary to arrange the small patterns in a given long sheet of paper with a minimum wastage. Another task of the company is to provide a way of cutting a stock material, e.g. given standard steel rods, into different number of smaller sized details in a way that minimizes the wasted material

Perspectives of 2D and 3D mapping of atmospheric pollutants over urban areas by means of airborne DOAS spectrometers

tants, offering numerous advantages over conventional networks of in situ analysers. We propose some innovative solutions in the field of DOAS (Differential Optical Absorption Spectroscopy) remote systems, utilizing diffuse solar light as the radiation source. We examine the numerous potentialities of minor gas slant column calculations, applying the «off-axis» methodology for collecting the diffuse solar radiation. One of these particular approaches, using measurements along horizontal paths, has already been tested with the spectrometer installed on board the Geophysica aircraft during stratospheric flights up to altitudes of 20 km. The theoretical basis of these new measurement techniques using DOAS remote sensing systems are delineated to assess whether low altitude flights can provide 2D and 3D pollution tomography over metropolitan areas. The 2D or 3D trace gas total column mapping could be used to investigate: i) transport and dispersion phenomena of air pollution, ii) photochemical process rates, iii) gas plume tomography, iv) minor gas vertical profiles into the Planetary Boundary Layer and v) minor gas flux divergence over a large area

Satb1 Regulates Contactin 5 to Pattern Dendrites of a Mammalian Retinal Ganglion Cell

The size and shape of dendritic arbors are prime determinants of neuronal connectivity and function. We asked how ON-OFF direction-selective ganglion cells (ooDSGCs) in mouse retina acquire their bistratified dendrites, in which responses to light onset and light offset are segregated to distinct strata. We found that the transcriptional regulator Satb1 is selectively expressed by ooDSGCs. In Satb1 mutant mice, ooDSGC dendrites lack ON arbors, and the cells selectively lose ON responses. Satb1 regulates expression of a homophilic adhesion molecule, Contactin 5 (Cntn5). Both Cntn5 and its co-receptor Caspr4 are expressed not only by ooDSGCs, but also by interneurons that form a scaffold on which ooDSGC ON dendrites fasciculate. Removing Cntn5 from either ooDSGCs or interneurons partially phenocopies Satb1 mutants, demonstrating that Satb1-dependent Cntn5 expression in ooDSGCs leads to branch-specific homophilic interactions with interneurons. Thus, Satb1 directs formation of a morphologically and functionally specialized compartment within a complex dendritic arbor