A color image watermarking framework for copyright protection of stereo images based on binocular just noticeable difference and LU decomposition

Multimedia Tools and Applications - The copyright protection of three-dimensional (3D) content is a matter of interest in artistic and creative works due to the rights of the holder for the...     

Rheological studies with spherically shaped thin liquid films

The present work shows the first experimental and theoretical results for investigations on the rheology of liquid films. The experiments are planned to be performed under microgravity conditions. This environment will allow forming films of different thickness, which is impossible under ground conditions due to drainage. Then the films are forced to harmonic oscillations of the film area so that the film elasticity can be measured as a function of frequency. The presented theoretical model demonstrates the main relationships to be solved under corresponding boundary conditions     

Neural network-based calibration of electromagnetic tracking systems

Electromagnetic tracking systems are a common component of many virtual reality installations. Their accuracy, however, suffers from the distortions of the electromagnetic field used in calculating the tracker sensor’s position. We have developed a tracker calibration technique based on a neural network that effectively compensates for the errors in both tracked location and orientation. This case study discusses our implementation of the calibration algorithm and compares the results with traditional calibration methods.     

A combined-cycle refrigeration system using ejector-cooling cycle as the bottom cycle

A combined-cycle refrigeration system (CCRS) that comprises a conventional refrigeration and air-conditioning system using mechanical compressor (RAC/MC) and an ejector-cooling cycle (EJC) is proposed and studied. The EJC is driven by the waste heat from the RAC/MC and acts as the bottom cycle of the RAC/MC. A system analysis shows that the COP of a CCRS is significantly higher than a single-stage refrigeration system. Improvement in COP can be as high as 18.4% for evaporating temperature of the RAC/MC T_e at −5°C. A prototype of the CCRS was built and tested in the present study. Experimental results show that at T_e=−4.5°C, COP is improved by 14% for a CCRS. For T_e at 5°C, COP can be improved by 24% for a CCRS with higher condensing temperature of the RAC/MC. The present study shows that the CCRS using the ejector-cooling cycle as the bottom cycle of the RAC/MC is viable. Further improvement in COP is possible since the prototype is not designed and operated at an optimal condition.     

The beamfilling algorithm for retrieval of hydrometeor profileparameters from passive microwave measurements

The horizontal inhomogeneity of the atmosphere within a satellite microwave radiometer's field of view (FOV) has always been considered as a source of rainfall retrieval errors. The hydrometeor profile retrieval algorithm presented exploits it to obtain an approximation of a radiative transfer model, which allows relatively simple inversion. The atmosphere within the FOV is treated as a combination of horizontally homogeneous domains. Assuming that one of known “basic” hydrometeor profiles occurs in each domain, the inverse problem is reduced to a determination of “beamfilling coefficients.” The online procedure includes determination of beamfilling coefficients and a footprint-averaged hydrometeor profile as a linear combination of “basic” ones. Off-line procedures involve the selection of a minimum number of necessary “basic” brightness temperature vectors and correction of “basic” hydrometeor profiles to provide the best retrieval accuracy for a given cloud/radiative simulation. The performance of the algorithm is tested for both numerical simulations and TRMM/TMI data. Numerical simulation has allowed a comparison of the information content of radiometer measurements from SSM/I, TMI, and the future AMSR. The effectiveness of the algorithm is being tested for rain water integral and rain rate retrievals from TRMM TMI measurements     

A SOLAR EJECTOR COOLING SYSTEM USING REFRIGERANT R141b

A high-performance solar ejector cooling system using R141b as the working fluid was developed. We obtain experimentally a COP of 0.5 for a single-stage ejector cooling system at a generating temperature of 90°C, condensing temperature of 28°C, and an evaporating temperature 8°C. For solar cooling application, an optimum overall COP can be obtained around 0.22 at a generating temperature of 95°C, evaporating temperature of 8°C and solar radiation at 700 W m⁻².     

Chloride and Indium‐Chloride‐Complex Inorganic Ligands for Efficient Stabilization of Nanocrystals in Solution and Doping of Nanocrystal Solids

Here, the surface functionalization of CdSe and CdSe/CdS core/shell nanocrystals (NCs) with compact chloride and indium‐chloride‐complex ligands is reported. The ligands provide not only short interparticle distances but additionally control doping and passivation of surface trap states, leading to enhanced electronic coupling in NC‐based arrays. The solids based on these NCs show an excellent electronic transport behavior after heat treatment at the relatively low temperature of 190 °C. Indeed, the indium‐chlorido‐capped 4.5 nm CdSe NC based thin‐film field‐effect transistor reaches a saturation mobility of μ = 4.1 cm² (V s)^?1 accompanied by a low hysteresis, while retaining the typical features of strongly quantum confined semiconductor NCs. The capping with chloride ions preserves the high photoluminescence quantum yield ( ≈ 66%) of CdSe/CdS core/shell NCs even when the CdS shell is relatively thin (six monolayers). The simplicity of the chemical incorporation of chlorine and indium species via solution ligand exchange, the efficient electronic passivation of the NC surface, as well as their high stability as dispersions make these materials especially attractive for wide‐area solution‐processable fabrication of NC‐based devices.     

Morphology, optical, and photoelectrochemical properties of electrodeposited nanocrystalline ZnO films sensitized with Cd x Zn1−x S nanoparticles

Nanocrystalline ITO/ZnO films formed by porous zinc oxide microplatelets 1–3 μm in size and 100–200 nm in thickness, which consist of 30–50 nm ZnO crystallites, were sensitized to visible light by Cd _x Zn_1?x S nanocrystals deposited using the method of successive ionic layer adsorption and reaction (SILAR). The composition of Cd _x Zn_1?x S nanocrystals as well as the dependence between molar Cd(II) fraction in the films and the ratio of cadmium and zinc nitrate concentrations in solutions used for the SILAR procedure were determined by a combination of electron, Raman, and energy-dispersive X-ray spectroscopies. The photovoltage observed at illumination of the ITO/ZnO/Cd _x Zn_1?x S heterostructures by white light (λ >400 nm) in aqueous Na₂S solution increases with a decrease of Cd(II) content proportionally to an increment in the conduction band potential of the Cd _x Zn_1?x S nanocrystals. The photocurrent density normalized to the light absorbance of the ITO/ZnO/Cd _x Zn_1?x S films increases by a factor of around four when the conduction band potential of Cd _x Zn_1?x S nanocrystals grows by 220 mV as a result of Cd(II) fraction changing from 1.0 to 0.62–0.67. The results show that Cd _x Zn_1?x S solid solutions are more advantageous sensitizers for the short-wavelength part of the sensitivity window of the liquid-junction solar cells (400–450 nm) than conventionally used cadmium sulfide.     

Development of Resource-Saving Technology of Linseed Harvesting

ABSTRACT

The traditional technology of linseed harvesting involves the cutting of the stems with subsequent threshing. During cutting part of the stem remains on the field, which causes significant losses of fibrous raw materials. Threshing of stems by traditional technology also causes significant damage to the linseed straw. Developed resource-saving technology of linseed harvesting provides first linseed thrashing on the plants with subsequent pulling of stems. With this sequence of technological operations, all linseed stems and seeds are preserved without damage. For the implementation of resource-saving technology proposed design of flax thresher and flax puller. The results of experimental studies of the properties of linseed fibre obtained from the linseed showed that such fibre is suitable for the production of non-woven materials, technical textiles and paper. The introduction of resource-saving technology of linseed harvesting will save the harvest of seeds and straw with minimal losses and damage. Resource-saving technology will increase the profitability of linseed cultivation.     

Removing the outliers in root-MUSIC via pseudo-noise resampling and conventional beamformer

A joint use of pseudo-noise resampling technique and a conventional beamformer is proposed to mitigate the effect of outliers in Root-MUSIC estimator. After resampling of Root-MUSIC via pseudo-randomly generated noise we combine it with a conventional beamformer (in the sense that identification of the signal roots is based on the power of the conventional beamformer response). The resulting estimator can be referred to as modified resampled Root-MUSIC. The estimator bank is formed from a number of modified resampled Root-MUSIC. Censored selection of the results of modified pseudo-randomly resampled Root-MUSIC estimators is exploited based on an appropriate local performance test.