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Background: Kernel Fisher discriminant analysis (KFDA) is a nonlinear discrimination technique for improving automatic modulation classification (AMC) accuracy. Our study showed that the higher-order cumulants (HOCs) of the Long-term evolution (LTE) modulation types are nonlinearly separable, so the KFDA technique is a good solution for its modulation classification problem. Still, research papers showed that the KFDA suffers from high time and space computational complexity. Some studies concentrated on reducing the KFDA time complexity while preserving the AMC performance accuracy by finding faster calculation techniques, but unfortunately, they couldn't reduce the space complexity. Objective: This study aims to reduce the time and space computational complexity of the KFDA algorithm while preserving the AMC performance accuracy. Methods: Two new time and space complexity reduction algorithms have been proposed. The first algorithm is the most discriminative dataset points (MDDP) algorithm, while the second is the k-nearest neighbors-based clustering (KNN-C) algorithm. Results: The simulation results show that these algorithms could reduce the time and space complexities, but their complexity reduction is a function of signal-to-noise ratio (SNR) values. On the other hand, the KNN-C-based KFDA algorithm has less complexity than the MDDP-based KFDA algorithm. Conclusion: The time and space computation complexity of the KFDA could be effectively reduced using MDDP and KNN-C algorithms; as a result, its calculation became much faster and had less storage size.

We used the binary collision approximation code Marlowe to simulate displacement cascades in tantalum monocarbide. We investigated the damage production, the spatial configurations of the resulting defects, and the vacancy clustering. Statistics over 5000 cascades were accumulated, and primaries with kinetic energies up to 20 keV were launched from lattice sites. Elastic collisions between atoms were modeled by the universal Ziegler–Biersack–Littmark, Moliere, and Born–Mayer potentials. The Lindhard–Scharff–Schiott theory was used to account for the inelastic energy losses. Principal components analysis was utilized to evaluate the volume of the damaged zone. Analysis of the simulation results shows that no more than 40% of the displaced Ta and C atoms constitute permanent damage. The number of surviving tantalum Frenkel pairs is about twice the carbon one. The cascade volume distributions deviate from a Gaussian distribution showing high degree of dispersion. Only small vacancy clusters are observed within the investigated range of the primary energies, and 33% of the produced vacancies are considered as isolated point defects in 20 keV cascade.

1 Abstract The crime of breach of regulations on rules of economic competition This thesis deals with the crime of breach of regulations on rules of economic competition under section 248 of the Criminal Code. This section consists of four separated crimes, where the author focuses only on the crime of unfair competition and the crime of conclusion of cartel agreement. In the first chapter the author concisely describes the historical background which is notable especially for legislation from period of the First Czechoslovak Republic. The author considers its significance mainly since the then Unfair Competition Act has been a source for the current provisions on unfair competition in the Civil Code. Moreover, the author intended to point out a very different rationale and approach to cartels under the then Act on Cartels in comparison with contemporary legal situation. After a general description of the elements of the crime in question in sense of systematic classification and introduction of its main issues the author presents two criminal law principles, i.e. subsidiarity of prosecution in criminal law and requirement of nullum crimen sine lege certa. The author examines both crimes in the light of these two principles throughout his whole thesis. In the third chapter the author inquires into legal...

This paper deals with the gaseous cascade amplification in He-H 2 O mixture in an ESEM. It is shown that such a mixture has the same behavior and gas amplification gain slightly modified with the increase of the (pd) parameter as compared to pure Helium. The use of the mixture gives rise to higher gain with respect to water vapor and more efficiency in the electrical neutralization of the specimen surface compared to He. All in all, the mixture exhibits high Townsend ionization coefficient, high gain and low operating voltage, which allows an expected increase of the signal to noise ratio.

This paper reports on Monte Carlo simulations of electrons propagation in water vapor using a set of electron collision cross sections created with data published recently in order to follow the beam profile at low energy in environmental scanning electron microscopy (ESEM). Results show that lowering electrons beam energy or pressure has little effect on the skirt extend which is mainly function of working distance. The ionization and excitation events per track history are independent of the initial electron energy in the 1–5 keV range. Ionization occurs with low energy electrons, frequently above 50 eV, whereas the excitation processes are dominated by the electrons below 50 eV.

The full potential linear muffin-tin orbital (FP-LMTO) method was applied to study the structural and electronic properties of the compounds MgO, ZnO and their alloy MgxZn1–xO in the zincblende and NaCl structures. Results are obtained using the local density approximation (LDA), the ground-state properties like lattice constant and bulk modulus obtained agree very well with experimental and other theoretical calculations. The effect of composition on lattice constant from Vegard’s law and the bulk modulus was investigated. The microscopic origins of the gap bowing were explained by using the approach of Zunger and co-workers. It is concluded that the energy band gap bowing is primarily due to chemical charge-transfer effect. Contribution of volume deformation and structural relaxation to the gap bowing parameter is found to be very small.

We have performed first-principles calculations of structural, elastic, thermodynamic, and electronic properties of anti-perovskites AIIICNi3 (AIII = Al, Ga, In), by using the full-potential linearized augmented plane wave (FP-LAPW) method combined with the quasi-harmonic Debye model. We carried out our calculations within the local density approximation (LDA) and the generalized gradient approximation (GGA-PBE and GGA-PBEsol functionals). Our results constitute interesting first predictions in the case of many elastic parameters of the anti-perovskites AIIICNi3, among them elastic parameters of AlCNi3 and GaCNi3 and some polycrystalline elastic parameters of InCNi3. We also report for the first time calculated values, at ambient conditions, of Gruneisen parameter, thermal expansion coefficient, specific heat at constant pressure, specific heat at constant volume, isothermal bulk modulus, and adiabatic bulk modulus for AlCNi3, GaCNi3, and InCNi3. Band structure, total and partial densities of states, and charge density have been obtained and analyzed. Electronic structure results show metallic behavior for the three compounds. Ni 3d states play dominant role near the Fermi level and there is a strong hybridization between Ni 3d and C 2p states. In addition, as AIIICNi3 synthesized samples are expected to be carbon-deficient, we calculated structural, elastic, and thermodynamic properties of sub-stoichiometric AlC x Ni3 materials.

The effects of various gas environment used in high pressure SEM inside the specimen chamber were investigated using Monte Carlo simulation. In order to improve the signal to noise ratio for the electron detection, we suggest to use helium gas-based mixture. The Helium gas is well known to reduce the skirt effect due to its low elastic scattering cross-section. The addition of an ionizing gas such as hydrogen or nitrogen is proposed to increase the inelastic scattering cross section which is mainly responsible for the ionisation process taking place during the beam-gas interactions. For all the mixtures (except He–Argon), the main results show that the skirt is slightly modified with the increase of the pressure. For the BSE detection, the signal to noise can remain high and gives a good contrast in imaging. Moreover, the presence of an ionizing gas will favour the ionizing process which is very important in beam-based electron detection. In this case, an increase of the signal to noise ratio can be expected.

A mathematical formalism is developed which describes the anodic dissolution of p-type Si in fluoride electrolyte within the first plateau of the electropolishing region. In this region, the silicon surface is coated with a wet oxide layer modelled as a composite medium [SiO2]1−h[H2O]h where the local volume fraction of water, h, decreases in the depth of the layer with decreasing distance from the silicon surface. Our theoretical approach based on the resolution of coupled non-linear differential equations involving the h function and the local fluoride concentration fits fairly well typical experimental voltammograms and oxide thickness measurements up to the beginning of the second electropolishing plateau.

The basic voltammetric data of silicon/ fluoride-electrolyte interfaces available in the literature appear to be rather divers because of the large number of experimental parameters like semiconductor type, crystallographic orientation, fluoride acid concentration CF, pH and electrode rotation rate. In the present work we have studied the effects of parameters such as electrode rotating rate upon the voltammograms in order to show the electrode geometry effects on current transport through Si/HF interface. The decrease of the current experimentally observed after the initial current peak (Si/HF current-potential curve) is investigated. The origin of this behaviour lies in substitution of Si-H surface bond by SiO2 in the first seconds following the potential jump. The diffusion current problem of a rotating porous silicon electrode has been analysed based on the mass transfer equations for partially blocked electrode. The blocking parameter is calculated.

By employing the first-principles method of the full potential linear augmented plane waves (FPLAPW), the structural, elastic and the electronic properties of LaBi are investigated. It is found that this compound has a semiconducting small and indirect gap. Through the quasi-harmonic Debye model, in which the phononic effects are considered, we have obtained successfully the thermodynamic properties such as thermal expansion coefficient, Debye temperature and specific heats in the whole pressure range from 0 to 10 GPa and temperature range from 0 to 1600 K.

The effect of the specimen inclination on the electron distribution at the specimen surface in an HPSEM was investigated by Monte Carlo simulation. A broadening of the electron profile versus the tilt angle was obtained and a relationship between the r(0.9) radius and this tilt angle is proposed. The plot of the electron distribution at the sample surface shows that the classical scattering profile in the standard conditions is modified so that an inclined truncated shape is obtained. This result confirms the difficulty to carry out X-ray microanalysis in low vacuum conditions.

Helium gas and air are commonly used in the high pressure scanning electron microscope (HPSEM). The presence of a gaseous environment in the specimen chamber modifies the electron beam profile. In order to fully understand the beam-gas interaction, we have investigated the beam-diameter effect for two gases (helium and air) by Monte Carlo simulation. In this calculation, we have assumed that the electron beam is Gaussian and we have explored the influence of the nature of the gas at low voltage. When the beam diameter varies between 1 and 100 nm, there is no influence on the beam profile for these two gases. The resolving power of the HPSEM is not affected by the beam-gas interaction. These theoretical results have been compared with experimental images obtained at low voltage under air and helium gases. The variation of image quality at low voltage has confirmed the interest of helium for use in a Field Emission Gun SEM (FEGSEM) in high pressure (or low vacuum) conditions.

X-ray microanalysis (XRMA) coupled to a variable pressure scanning electron microscope (VP-SEM) using air atmosphere in the specimen chamber performed on test structures were used to make comparison with a Monte Carlo simulation program based on the modeling of the electron beam-gas interaction. The results show that the extent of the beam spreading can be significantly reduced at relatively high pressures by using helium gas instead of air and considerably reduced even at low pressure by lowering the analytical distance.

The effects of three different gas environments formed by pure argon, helium and nitrogen with variable pressures up to 300 Pa inside the specimen chamber of a scanning electron microscope on the electron beam parameters were investigated and compared using Monte Carlo calculations. The calculations show that the skirt of the electron beam probe is nearly independent of pressure in the case of helium, which is also supported by experimental evidence. Both theoretical simulation and experimental facts indicate helium as the environment of choice in specimen chambers for minimizing the effect of beam–gas interactions.

In the context of the optimization of InP Rapid Thermal Annealing (RTA), two methods were analyzed and compared. In the first one, the sample is sandwiched between two silicon wafers. It is enclosed in a graphite cell in the second one. Deep level transient spectroscopy (DLTS) implemented on two InP samples annealed with identical effective thermal budgets, shows an additional electron trap when RTA is performed in the graphite cell. The latter mode was optimized for a plateau duration of about 10 s at 750 °C as confirmed by capacitance–voltage (C–V) measurements.

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