Synthesis and characterization of the SBA-15/carbon cryogel nanocomposites

The ordered mesoporous silica SBA-15 materials were synthesized using Pluronic P123 (non-ionic triblock copolymer, EO₂₀PO₇₀O₂₀), under acidic conditions. SBA-15/carbon cryogel composites were obtained by sol–gel polycondensation of resorcinol and formaldehyde followed by freeze drying, and subsequent pyrolysis, in the presence of different amounts of SBA-15. For comparison purpose, SBA-15/carbon composite was also prepared using sucrose as carbon source. These materials were characterized by room temperature nitrogen adsorption–desorption measurement, X-ray diffraction, scanning electron microscopy (SEM) and Fourier transform infrared (FT-IR) spectroscopy. It was revealed that the samples have amorphous structure, high specific surface area (350–520 m² g^?1) and developed meso- as well as microporosity. The porosity of structure depends on the carbon source and Si/C ratio which can be easily controlled by varying concentration of starting solution.     

Research of influences of surface structure of coloured textiles: applying fuzzy logic

The fuzzy logic‐based approach was applied in studying the influence of a different textile surface structure on colour appearance and similarity. The fuzzy‐based approach has been chosen because fuzzy logic provides the computerising of human reasoning. For the analyses, 100% cotton samples with certain characteristics were chosen. First, the computer match prediction was performed to determine the concentrations of dyestuff to be used in the experimental work. A yellow‐shaded direct dyestuff suitable for cotton dyeing was used. In the next step, the fuzzy logic system was created based on terms that would define the surface characteristics of the samples. The most important part was a proper definition of the rules and linguistic variables that use words for assigning the values of properties and that influence the experience of an observer (gloss, smoothness, roughness, etc.) and connect input space with output space. Finally, the performances of both systems were compared and analysed. In this work, the approach was based solely on the surface–structural characteristics of textile samples. The main aim was to examine the approach using the fuzzy logic‐based technique in order to provide the method that would include surface parameters of textile samples that are of importance in applying colour to different structured textile surfaces. It was confirmed that the fuzzy logic reasoning would have its application in the control of the influence of the surface structure of coloured textiles, especially for lighter shades where the influence of structure parameters on the colour experience of an observer is more emphasised.     

COMPARISON OF CONVECTIVE, VACUUM, AND MICROWAVE DRYING CHLORPROPAMIDE

Drying kinetics of convective, vacuum, and microwave drying of a pharmaceutical product, chlorpropamide, has been investigated on a laboratory scale, in the temperature interval from 40°C to 60°C, and the range of microwave heating power from 154 W/kg_dm to 385 W/kg_dm.

The experimental data obtained were approximated with the “thin-layer” equation and a two parameter exponential model. In order to compare convective, vacuum, and microwave drying, effective diffusion coefficients and specific heat consumption were calculated for each drying method.

Higher rates and shorter drying times were achieved at a higher temperature and microwave heating power. The highest drying rates and the lowest specific heat consumption were achieved with microwave drying. This leads to the conclusion that microwave heating is the most appropriate method for drying of chlorpropamide. The quality of product was not changed for all applied methods.     

Reliability analysis of net cross-section resistance with accidental eccentricity of holes

The aim of the research was to determine reliability function of net cross-section resistance in relation to accidental eccentricity of nominally centric holes. The response surface method was used by taking into account the relevant Eurocode design provisions and reliability requirements. Within the response surface method, the central composite design method and the least square method were used with the employment of Monte Carlo simulations. The probable distributed variables such as strength f _y, breadth b, thickness t, diameter d ₀ and eccentricity e were determined by the central composite design method. 280 different numerical simulations were set up with varying variables. A log-normal distribution for strength (f _y) and a normal distribution for geometrical variables (b, t, d ₀,e) were employed by taking into account the coefficients of variations: V _fy=0.07, V _b,=0.005, V _l=0.05 and V _d0=0.005. In order to determine the influence of eccentricity on partial safety factor, several normal distributions with different variation factors were applied in the analysis. The influence of the edge distance of the hole e ₂ over d ₀ ratio on the partial safety factor was determined by varying mean values of variable b. For comparison, two types of steel were used: structural steel S235 and high strength steel S690. Numerical simulations of the net cross-section resistance F _u were performed with ABAQUS 6.7. The response surface for the net cross-section resistance was determined by introducing a quadratic approximation function and by applying the least square method. The partial safely factor was then (statistically) obtained by means of robust Monte Carlo simulations on the calculated response surface.     

Extended Approach to Water Flow Algorithm for Text Line Segmentation

This paper proposes a new approach to the water flow algorithm for text line segmentation. In the basic method the hypothetical water flows under few specified angles which have been defined by water flow angle as parameter. It is applied to the document image frame from left to right and vice versa. As a result, the unwetted and wetted areas are established. These areas separate text from non-text elements in each text line, respectively. Hence, they represent the control areas that are of major importance for text line segmentation. Primarily, an extended approach means extraction of the connected-components by bounding boxes over text. By this way, each connected component is mutually separated. Hence, the water flow angle, which defines the unwetted areas, is determined adaptively. By choosing appropriate water flow angle, the unwetted areas are lengthening which leads to the better text line segmentation. Results of this approach are encouraging due to the text line segmentation improvement which is the most challenging step in document image processing.     

Biosynthesis of the Insecticidal Xenocyloins in Xenorhabdus bovienii

The biosynthesis gene cluster for the production of xenocyloins was identified in the entomopathogenic bacterium Xenorhabdus bovienii SS‐2004, and their biosynthesis was elucidated by heterologous expression and in vitro characterization of the enzymes. XclA is an S‐selective ThDP‐dependent acyloin‐like condensation enzyme, and XclB and XclC are examples of the still‐rare acylating ketosynthases that catalyze the acylation of the XclA‐derived initial xenocyloins with acetyl‐, propionyl‐, or malonyl‐CoA, thereby resulting in the formation of further xenocyloin derivatives. All xenocyloins were produced mainly by the more virulent primary variant of X. bovienii and showed activity against insect hemocytes thus contributing to the overall virulence of X. bovienii against insects.     

Contribution to development of risk analysis methods by application of artificial intelligence techniques

During the life cycle of technical systems, precise and detail failure risk analysis gives suitable input elements for taking appropriate actions, which allows reducing of unwanted uncertainty and occurrences. Traditional method for risk analysis, which is applied for many years, especially in analysis of functionality of technical systems, is Failure Mode and Effects Analysis (FMEA) method. However, in many cases, this method shows weaknesses related to the inconsistency, which is a result of insecure subjectivity during the determination of values for parameters that gives Risk Priority Number (RPN), as well as other weaknesses. This paper shows contribution to the development of failure risk analysis based on FMEA method. Contribution of the development of risk analysis methods is given through modification of traditional FMEA method by integration of artificial intelligence techniques, in this case, by integration of fuzzy logic and by including a few principles based on special classification of recognized failures. Thus, it is minimized effect of methodological inconsistency and some of other identified weaknesses of traditional FMEA method. FMEA method is improved, which provides more precise failure risk evaluation and thus better prediction and minimizing of unwanted occurrences (failures of elements, subsystems, components, etc., of technical systems). It was proved by comparative analysis of applied traditional FMEA method as well as modified FMEA method, hereinafter called “intelligent” FMEA method (IFMEA) on system of tires for city busses.