bluuebunny/crossref_metadata_2025 huggingface dataset:
Risk assessment at work and prevention strategies on COVID-19 in Italy
Authors: Iavicoli Sergio , Boccuni Fabio , Buresti Giuliana , Gagliardi Diana , Persechino Benedetta , Valenti Antonio , Rondinone Bruna Maria
Published: March 2021

The COVID-19 pandemic has spread worldwide, with considerable public health and socio-economic impacts that are seriously affecting health and safety of workers, as well as their employment stability. Italy was the first of many other western countries to implement extended containment measures. Health workers and others employed in essential sectors have continued their activity, reporting high infection rate with many fatalities. The epidemiological trend highlighted the importance of work as a substantial factor to consider both when implementing strategies aimed at containing the pandemic and shaping the lockdown mitigation strategy required for sustained economic recovery. To support the decision-making process, we have developed a strategy to predict the risk of infection by SARS-CoV-2 in the workplace based on the analysis of the working process and proximity between employees; risk of infection connected to the type of activity; involvement of third parties in the working processes and risk of social aggregation. We applied this approach to outline a risk index for each economic activity sector, with different levels of detail, also considering the impact on mobility of the working population. This method was implemented into the national epidemiological surveillance model in order to estimate the impact of re-activation of specific activities on the reproduction number. It has also been adopted by the national scientific committee set up by the Italian Government for action-oriented policy advice on the COVID-19 emergency in the post lockdown phase. This approach may play a key role for public health if associated with measures for risk mitigation in enterprises through strategies of business process re-engineering. Furthermore, it will make a contribution to reconsidering the organization of work, including also innovation and fostering the integration with the national occupational safety and health (OSH) system.
Cervical cytology and associated factors among tribal women of Karnataka, India
Authors: Ghosh Supriti , Pattanshetty Sanjay M. , Mallya Sneha D. , Pandey Deeksha , Guddattu Vasudeva , Kamath Veena G. , Kabekkodu Shama Prasada , Satyamoorthy Kapaettu , Shetty Ranjitha S.
Published: March 2021

Background

Reproductive well-being is a crucial element of women’s health. Due to the asymptomatic nature of gynaecological morbidities, women rarely seek medical advice in the initial period leading to delayed diagnosis and poor prognosis of subsequent disease. The present study aimed to explore the cervical cytology and its associated risk factors among women from tribal communities of the southern part of coastal Karnataka, India.

Methods

Papanicolaou (Pap) smear test was performed among 1140 women from three tribal populations, to detect cervical lesions, infections and reactive changes. A semi-structured questionnaire was administered to collect data on socio-demographic and reproductive characteristics of the study population.

Results

The most predominant gynaecological complaint among the participants was severe lower back ache (77.6%), followed by white discharge per vagina (29.0%) and menstrual irregularities (25.9%). Of the 1140 women screened, 12.4% showed cervical microbial infections, 23.6% were reported to have reactive changes, and 0.2% had epithelial cell abnormalities in the cervix. Cervical microbial infections were found to be associated with younger age group, low socio-economic status and younger age at sexual debut.

Conclusion

Most of the symptoms suggestive of gynaecological morbidities reported in this study are preventable or treatable. Strengthening ongoing cervical cancer screening programme and implementation of health education programmes among tribal population would be the right policy approach to prevent, detect and treat these symptoms at an early stage and to achieve acceptable health outcomes among tribal women.
Beauty or beast? Farmers’ dualistic views and the influence of aesthetic appreciation on tolerance towards black-backed jackal and caracal
Authors: Drouilly Marine , Nattrass Nicoli , O’Riain M. Justin
Published: March 2021

Various species of wild, adaptable, medium-sized carnivores occur outside of protected areas, often coming into contact with people and their domestic animals. Negative human-carnivore interactions can lead to antagonistic attitudes and behavior directed at such species. In the South African Karoo, a semi-arid rangeland, the predation of small-livestock by mesopredators is common and farmers typically use a combination of non-lethal and lethal methods to try and prevent livestock losses. We used ethnographic field observations and semi-structured interviews as part of a mixed methods approach, including the quantitative and qualitative analysis of farmers’ narratives to illustrate the nuanced ways in which sheep farmers relate to the two mesopredators that consume the most livestock on their farms; black-backed jackal and caracal. Overall, farmers attributed negative characteristics to jackal and caracal but farmers’ narratives provided evidence of complex perceptions in that the animals were admired as well as disliked. Both species were seen as charismatic due to traits such as their physical appearance, their “cunning” nature and their remarkable adaptability to human activities, including lethal control. Aesthetic appreciation was an important predictor of tolerance towards both species whereas negative attitudes were associated with the perception that mesopredators should only occur within protected areas. Attitudes towards jackals also appeared to have been affected by cultural representations of them as “thieves”. We showed that perceiving mesopredators as beautiful increased the average marginal probability of a farmer tolerating them, and that this strong relationship held when controlling for other covariates such as livestock predation. We advocate the importance of understanding the cultural and aesthetic aspects of predators and considering existing positive dimensions of human-wildlife relationships that may encourage increased farmers’ tolerance, which might promote coexistence.
Presentación de los Directores
Authors: Santos Pérez José Manuel , Beçak Rubens
Published: March 2021

Texto de presentación del número 15 (volumen 7) de la Revista de Estudios Brasileños.
La acción exterior de Brasil a examen. Entrevista a Bruno Ayllón Pino, especialista en el estudio de las relaciones internacionales brasileñas
Authors: Santos Pérez José Manuel , Tavares Duarte Elisa
Published: March 2021

Entrevista con el politólogo y especialista en las relaciones España-Brasil, Bruno Ayllón Pino, autor del libro Las relaciones hispano-brasileñas: de la mutua irrelevancia a la asociación estratégica (1945-2005), en la que se abordan cuestiones como la trayectoria investigadora, el papel que juega Brasil en el concierto internacional, el estado de las relaciones entre Brasil y España, la acción cultural brasileña, la cooperación Sur-Sur y el presente y futuro de todos estos campos de estudios.
Characterization of putative pathogenic Shewanella algae isolated from ballast water
Authors: Ibrahim Nik Nuraznida Nik , Nasir Nurathirah Mat , Sahrani Fathul Karim , Ahmad Asmat , Sairi Fareed
Published: March 2021

Background and Aim: Shewanella algae is ubiquitous in marine-associated environments and has been increasingly recognized as a significant human pathogen that can cause serious infections mainly associated with exposure to seawater and ingestion of raw seafood. This study aimed to isolate and characterize S. algae from ballast water of ships berthed at Port Klang, Malaysia.

Materials and Methods: Ballast water was sampled from nine ships docked at Port Klang, Malaysia. The isolates were identified and characterized based on biochemical and enzymatic properties, 16S rRNA and gyrB sequencing, biofilm formation capability, and antibiotic susceptibility.

Results: A total of four S. algae isolates were isolated from four ballast water samples tentatively name Sa-BW1, Sa-BW2, Sa-BW7, and Sa-BW8. All isolates showed positive reaction for cytochrome oxidase, catalase, high tolerance to NaCl (6% and 8%), ability to grow at 42°C, and on Salmonella-Shigella agar. The strains also exhibited β-hemolytic activity on sheep blood and human blood agar, positive reaction for lipase, protease, DNase and gelatinase, strong biofilm adherence capabilities and multiple antibiotic resistances against ampicillin, carbenicillin, cephalothin, colistin, novobiocin, oxacillin, penicillin, rifampicin, and tobramycin which suggested their potential pathogenicity.

Conclusion: This study demonstrated the occurrence of putative pathogen S. algae in ballast water of ships docked at Malaysian port.
Antimicrobial resistance profiles of Escherichia coli from swine farms using different antimicrobials and management systems
Authors: Ketkhao Pramualchai , Thongratsakul Sukanya , Poolperm Pariwat , Poolkhet Chaithep , Amavisit Patamabhorn
Published: March 2021

Background and Aim: The emerging of antimicrobial-resistant foodborne bacteria is a serious public health concern worldwide. This study was conducted to determine the association between farm management systems and antimicrobial resistance profiles of Escherichia coli isolated from conventional swine farms and natural farms. E. coli isolates were evaluated for the minimum inhibitory concentration (MIC) of 17 antimicrobials, extended-spectrum beta-lactamase (ESBL)- producing enzymes, and plasmid-mediated colistin-resistant genes.

Materials and Methods: Fecal swabs were longitudinally collected from healthy pigs at three stages comprising nursery pigs, fattening pigs, and finishers, in addition to their environments. High-generation antimicrobials, including carbapenem, were selected for the MIC test. DNA samples of colistin-resistant isolates were amplified for mcr-1 and mcr-2 genes. Farm management and antimicrobial applications were evaluated using questionnaires.

Results: The detection rate of ESBL-producing E. coli was 17%. The highest resistance rates were observed with trimethoprim/sulfamethoxazole (53.9%) and colistin (48.5%). All isolates were susceptible to carbapenem. Two large intensive farms that used colistin-supplemented feed showed the highest colistin resistance rates of 84.6% and 58.1%. Another intensive farm that did not use colistin showed a low colistin resistance rate of 14.3%. In contrast, a small natural farm that was free from antimicrobials showed a relatively high resistance rate of 41.8%. The majority of colistin-resistant isolates had MIC values of 8 μg/mL (49%) and ≥16 μg/mL (48%). The genes mcr-1 and mcr-2 were detected at rates of 64% and 38%, respectively, among the colistin-resistant E. coli.

Conclusion: Commensal E. coli were relatively sensitive to the antimicrobials used for treating critical human infections. Colistin use was the primary driver for the occurrence of colistin resistance in swine farms having similar conventional management systems. In the natural farm, cross-contamination could just occur through the environment if farm biosecurity is not set up carefully, thus indicating the significance of farm biosecurity risk even in an antimicrobial-free farm.
A szolgáltatások ellátási láncának speciális menedzsmentjellemzői (Management specialties of supply chain of services)
Authors: Gelei Andrea , Gémesi Katalin
Published: March 2021

Az elmúlt évtizedekben a gazdálkodástudomány kitüntetett figyelemmel kísért két – mind a makrogazdaság, mind az egyes vállalatok működésének sikere szempontjából meghatározó fontosságú – jelenséget, egyrészt a szolgáltatásoknak a hagyományos termeléssel szembeni egyre erőteljesebb térnyerését, másrészt a fogyasztói érték teremtése szempontjából növekvő jelentőségű ellátási láncoknak, illetve azok menedzsmentjének kérdéskörét. Ugyanakkor igen kevés elemzés, de kevés leíró jellegű munka is született a két jelenséget és menedzsmentproblémát összekapcsoló területről, azaz a szolgáltatások ellátási láncáról, ezen ellátási láncok kezelésének speciális problémáiról. A szerzők cikkükben a szolgáltatások ellátási láncának és menedzsmentjének jellegzetességeit, a klasszikus terméket előállító ellátási láncokhoz viszonyított sajátosságait foglalják össze a nemzetközi szakirodalom alapján. Ennek során bemutatják, hogy az ún. tiszta szolgáltatások széles körben ismert jellemzői hatással vannak a szolgáltatások előállítását és értékesítését végző ellátási láncok működésére is. Ezek a hatások és specialitások megjelennek az ellátásilánc-menedzsment irodalmában kiemelten tárgyalt mindhárom problémakörben, rányomják tehát bélyegüket mind az ellátási lánc felépítésére, mind az ellátási láncban együttműködő partnerek kapcsolatának kezelésére és végül, de nem utolsósorban az ellátásilánc-menedzsment folyamatok kezelésére. _________ In the last decades scholars have paid a lot of attention to both service operation and supply chain management. There is still limited research on the overlapping field of theses two management areas, on service supply chain specialties. This article gives a structured overview on the latest research results on this topic. Doing so the paper would like to draw attention of the Hungarian researchers to this field and facilitate these empirical researches. As described in the paper traditional service specialties (intangibility, perishability, inseparability, heterogeneity and the importance of human capital) create special management problems concerning (i) the structure of these supply chains, (ii) their relationship management and (iii) the management of supply chain processes.
Statistics of Electron Avalanches and Streamers
Authors: Ficker T.
Published: March 2021

We have studied the severe systematic deviations of populations of electron avalanches from the Furry distribution, which has been held to be the statistical law corresponding to them, and a possible explanation has been sought. A  new theoretical concept based on fractal avalanche multiplication has been proposed and is shown to be a convenient candidate for explaining these deviations from Furry statistics.
Simulation Environment for Artificial Creatures
Authors: Kohout K. , Nahodil P.
Published: March 2021

Our research is focused on the design and simulation of artificial creatures – animates. This topic has been addressed in our research group for the last decade. The designed animates have been greatly inspired by sciences such as ethology, biology and psychology. Several agent architectures have been proposed and tested in recent years. We started to face the problem of comparing various architectures in order to benchmark them. Intelligence is embodied in our agent, and it needs an environment to be placed into. We have solved both these problems by first proposing and then implementing a common simulation environment in which these agents can run and compete. The main contribution of this paper is to offer a description of this designed simulation environment. It has been named the World of Artificial Life (WAL).
First Steps into Practical Engineering for Freshman Students Using MATLAB and LEGO Mindstorms Robots
Authors: Behrens A. , Atorf L. , Schwann R. , Ballé J. , Herold T. , Telle A.
Published: March 2021

Besides lectures on basic theoretical topics, contemporary teaching and learning concepts for first semester students give more and more consideration to practically motivated courses. In this context, a new first-year introductory course in practical engineering has been established in the first semester curriculum of Electrical Engineering at RWTH Aachen University, Germany. Based on a threefold learning concept, programming skills in MATLAB are taught to 309 students within a full-time block course laboratory. The students are encouraged to transfer known mathematical basics to program algorithms and real-world applications performed by 100 LEGO Mindstorms robots. A new MATLAB toolbox and twofold project tasks have been developed for this purpose by a small team of supervisors. The students are supervised by over 60 tutors at 23 institutes, and are encouraged to create their own robotics applications. We describe how the laboratory motivates the students to act and think like engineers and to solve real-world issues with limited resources. The evaluation results show that the proposed practical course concept successfully boosts students’ motivation, advances their programming skills, and encourages the peer learning process.
The Precision Simulation of the First Generation Matrix Converter
Authors: Bednář M.
Published: March 2021

This paper describes simulation of first generation matrix converter, which was realized in the lab. The simulation was developed in response to the need a diagnostic tool. The program is needed in order to debug the implemented control algorithms. The simulator supplies an environment for testing the generation of switching pulses without the risk of damaging the hardware. It supports the large potentiality for quicker development of new switching algorithms. A description of the simulated system is also included.
Acceleration of Sparse Matrix-Vector Multiplication by Region Traversal
Authors: Šimeček I.
Published: March 2021

Sparse matrix-vector multiplication (shortly SpM×V) is one of most common subroutines in numerical linear algebra. The problem is that the memory access patterns during SpM×V are irregular, and utilization of the cache can suffer from low spatial or temporal locality. Approaches to improve the performance of SpM×V are based on matrix reordering and register blocking. These matrix transformations are designed to handle randomly occurring dense blocks in a sparse matrix. The efficiency of these transformations depends strongly on the presence of suitable blocks. The overhead of reorganization of a matrix from one format to another is often of the order of tens of executions ofSpM×V. For this reason, such a reorganization pays off only if the same matrix A is multiplied by multiple different vectors, e.g., in iterative linear solvers.This paper introduces an unusual approach to accelerate SpM×V. This approach can be combined with other acceleration approaches andconsists of three steps:1) dividing matrix A into non-empty regions,2) choosing an efficient way to traverse these regions (in other words, choosing an efficient ordering of partial multiplications),3) choosing the optimal type of storage for each region.All these three steps are tightly coupled. The first step divides the whole matrix into smaller parts (regions) that can fit in the cache. The second step improves the locality during multiplication due to better utilization of distant references. The last step maximizes the machine computation performance of the partial multiplication for each region.In this paper, we describe aspects of these 3 steps in more detail (including fast and time-inexpensive algorithms for all steps). Ourmeasurements prove that our approach gives a significant speedup for almost all matrices arising from various technical areas.
Thermal – Oxidation Stability of Insulating Fluids
Authors: Semančík P. , Cimbala R. , Záliš K.
Published: March 2021

This paper deals with the thermal – oxidation stability of insulating fluids by the EEZ– ORGREZ test method [1]. It describes the principle test method as a preparation of experiment and the thermal – oxidation stability measuring of insulating oil.
Statistical Analysis of Input Parameters Impact on the Modelling of Underground Structures
Authors: Hilar M. , Pruška J.
Published: March 2021

The behaviour of a geomechanical model and its final results are strongly affected by the input parameters. As the inherent variability of rock mass is difficult to model, engineers are frequently forced to face the question “Which input values should be used for analyses?” The correct answer to such a question requires a probabilistic approach, considering the uncertainty of site investigations and variation in the ground. This paper describes the statistical analysis of input parameters for FEM calculations of traffic tunnels in the city of Prague. At the beginning of the paper, the inaccuracy in the geotechnical modelling is discussed. In the following part the Fuzzy techniques are summarized, including information about an application of the Fuzzy arithmetic on the shotcrete parameters. The next part of the paper is focused on the stochastic simulation – Monte Carlo Simulation is briefly described, Latin Hypercubes method is described more in details. At the end several practical examples are described: statistical analysis of the input parameters on the numerical modelling of the completed Mrázovka tunnel (profile West Tunnel Tube km 5.160) and modelling of the constructed tunnel Špejchar – Pelc Tyrolka.
Memory Hierarchy Behavior Study during the Execution of Recursive Linear Algebra Library
Authors: Šimeček I.
Published: March 2021

For good performance of every computer program, good cache and TLB utilization is crucial. In numerical linear algebra libraries (such as BLAS or LAPACK), good cache utilization is achieved by explicit loop restructuring (mainly loop blocking), but this requires difficult memory pattern behavior analysis. In this paper, we represent the recursive implementation (“divide and conquer” approach) of some routines from numerical algebra libraries. This implementation leads to good cache and TLB utilization with no need to analyze the memory pattern behavior due to “natural” partition of data.
Incorporation of Load Induced Thermal Strain in Finite Element Models
Authors: Law A. , Gillie M. , Pankaj P.
Published: March 2021

Load induced thermal strains (LITS) are an integral part of the behaviour of concrete in fire; their existence has been well documented and modelled by different researchers. More thorough representation of LITS is needed to accurately represent their plastic constituents in finite element models. This paper develops a technique to allow the evolution of LITS in accordance with the rules developed in several academic models. The technique is implemented with a simple Drucker-Prager yield surface and the results assessed.
Structural Analysis of Steel Structures under Fire Loading
Authors: Crosti C.
Published: March 2021

This paper focuses on the structural analysis of a steel structure under fire loading. In this framework, the objective is to highlight the importance of the right choice of analyses to develop, and of the finite element codes able to model the resistance and stiffness reduction due to the temperature increase. In addition, the evaluation of the structural collapse under fire load of a real building is considered, paying attention to the global behavior of the structure itself.
Fire Resistance of Axially Loaded Slender Concrete Filled Steel Tubular Columns – Development of a Three-Dimensional Numerical Model and Comparison with Eurocode 4
Authors: Espinós A. , Hospitaler A. , Romero M. L.
Published: March 2021

In recent years, concrete filled tubular (CFT) columns have become popular among designers and structural engineers, due to a series of highly appreciated advantages: high load-bearing capacity, high seismic resistance, attractive appearance, reduced column footing, fast construction technology and high fire resistance without external protection. In a fire, the degradation of the material properties will cause CFT columns to become highly nonlinear and inelastic, which makes it quite difficult to predict their failure. In fact, it is still not possible for analytical methods to predict with enough accuracy the behaviour of columns of this kind when exposed to fire. Numerical models are therefore widely sought. Many numerical simulations have been carried out worldwide, without obtaining satisfactory results. This work proposes a three-dimensional numerical model for studying the actual fire behaviour of columns of this kind. This model was validated by comparing the simulation results with fire resistance tests carried out by other researchers, as well as with the predictions of the Eurocode 4 simplified calculation model.
A New Design Method for Industrial Portal Frames in Fire
Authors: Song Y. , Huang Z. , Burgess I. , Plank R.
Published: March 2021

Industrial portal frames near to other buildings must keep their vertical walls standing in fire in order to prevent fire spread.  A recently developed analysis, implemented in the program Vulcan, using a combination of static and dynamic solvers, has shown that the strong base connections recommended by the current design method may not always lead to conservative design. A second-phase failure mechanism observed in numerical modelling, and the critical temperature at which final run-away collapse occurs, may be higher than the temperature at which the roof frame initially loses its stability, because a re-stabilisation often happens.  A new method for estimating critical temperatures of portal frames in fire, using these two failure mechanisms, is presented. Numerical tests on typical industrial frames are used to calibrate this new method.
Noise Reduction in Car Speech
Authors: Bolom V.
Published: March 2021

This paper presents properties of chosen multichannel algorithms for speech enhancement in a noisy environment. These methods are suitable for hands-free communication in a car cabin. Criteria for evaluation of these systems are also presented. The criteria consider both the level of noise suppression and the level of speech distortion. The performance of multichannel algorithms is investigated for a mixed model of speech signals and car noise and for real signals recorded in a car.
Technical and Economic Assessment of Storage Technologies for Power-Supply Grids
Authors: Meiwes H.
Published: March 2021

Fluctuating power generation from renewable energies such as wind and photovoltaic are a technical challenge for grid stability. Storage systems are an option to stabilise the grid and to maximise the utilisation factors of renewable power generators. This paper analyses the state of the art of storage technologies, including a detailed life cycle cost comparison. Beside this, benefits of using storage systems in electric vehicles are analysed and quantified. A comprehensive overview of storage technologies as well as possible applications and business cases for storage systems is presented.
Working Fluid Quantity Effect on Magnetic Field Control of Heat Pipes
Authors: Cingroš F. , Hron T.
Published: March 2021

This paper deals with heat pipes controlled by a static magnetic field and with an important side effect – the quantity of working fluid. Heat pipes are able to provide very effective heat transport. Several standard regulation methods are commonly used for this purpose. In previous experiments implemented in our laboratory, we have observed the significant influence of a magnetic field on the heat conductance of the selected heat pipe. A special heat pipe was manufactured for this purpose and pure oxygen was chosen as a working fluid, due to its suitable magnetic properties. The heat pipe operation and the magnetic field control depend on various parameters. This paper is focused on the influence of the quantity of working fluid. Some important results of our experiments are presented and discussed.
Demand Modelling in Telecommunications
Authors: Chvalina M.
Published: March 2021

This article analyses the existing possibilities for using Standard Statistical Methods and Artificial Intelligence Methods for a short-term forecast and simulation of demand in the field of telecommunications. The most widespread methods are based on Time Series Analysis. Nowadays, approaches based on Artificial Intelligence Methods, including Neural Networks, are booming. Separate approaches will be used in the study of Demand Modelling in Telecommunications, and the results of these models will be compared with actual guaranteed values. Then we will examine the quality of Neural Network models.
Capillary Discharge XUV Radiation Source
Authors: Nevrkla M.
Published: March 2021

A device producing Z-pinching plasma as a source of XUV radiation is described. Here a ceramic capacitor bank pulse-charged up to 100 kV is discharged through a pre-ionized gas-filled ceramic tube 3.2 mm in diameter and 21 cm in length. The discharge current has amplitude of 20 kA and a rise-time of 65 ns. The apparatus will serve as experimental device for studying of capillary discharge plasma, for testing X-ray optics elements and for investigating the interaction of water-window radiation with biological samples. After optimization it will be able to produce 46.9 nm laser radiation with collision pumped Ne-like argon ions active medium.
Implementation of a Power Combining Network for a 2.45 GHz Transmitter Combining LINC and EER
Authors: Wang F. , Koch O.
Published: March 2021

A power combining network with 180N hybrid for a 2.45 GHz Transmitter Combining LINC and EER has been analyzed, built and measured. The network feeds the wasted outphasing power partly back to the power supply and therefore improves the overall power efficiency. The recycling circuit was designed and simulated with ADS. A measured peak recycling efficiency of 60% was achieved with commercial Schottky diodes at 2.45 GHz at an input power of 36 dBm.
2.45 GHz Class E Power Amplifier for a Transmitter Combining LINC and EER
Authors: Dirix M. , Koch O.
Published: March 2021

A 10 W class-E RF power amplifier (PA) is designed and fabricated using a Cree GaN HEMT. The proposed PA uses an innovative input circuit to optimize band with. At 2.45 GHz the PA achieves a PAE of 60 % at an outputpower of 40 dBm. The resulting amplifier is simulated and constructed using a transmissionline topology. Two of these amplifiers are fabricated on a single board for outphasing application. Their suitability for outphasing application and supply modulation is investigated.
Reliability Risk Evaluation during the Conceptual Design Phase
Authors: Mamtani G. , Green G.
Published: March 2021

I (Relative Reliability Risk Index) is calculated and the idea of concept functionality graphs is presented.  This method is applied on the example of seat suspensions for an off highway vehicle and the results are discussed. The findings help to sort out the concepts that are relatively strong in terms of reliability.
Identification and Predictive Control by p-norm Minimization
Authors: Pekař J. , Štecha J.
Published: March 2021

Real time system parameter estimation from the set of input-output data is usually solved by minimization of quadratic norm errors of system equations – known in the literature as least squares (LS) or its modification as total least squares (TLS) or mixed LS and TLS. It is known that the utilization of the p-norm (1?p
Similarity Solutions of Jet Development Mixing Layers Using Algebraic and 1-Equation Turbulence Models
Authors: Tesař V.
Published: March 2021

Mixing layers are formed between two parallel fluid streams having different velocities. One of the velocities may be zero, as is the usual case of the mixing layer that surrounds, immediately downstream from the nozzle, the core of a developing jet issuing into stagnant surroundings. Earlier – but so far not properly published – experimental evidence shows a remarkably weak effect of transversal curvature, making the present solution applicable with acceptable precision to description of developing round jets. This paper presents solutions of a planar mixing layer by a similarity transformation, which reduces the problem to solving ordinary differential equations. Two solutions are investigated: one based on an algebraic model and the other using the 1-equation model of turbulence. They are compared with recent results of PIV measurements of a developing jet.
State of a Logical Object
Authors: Bokr J. , Jáneš V.
Published: March 2021

The paper deals with the state and performance of a logical object on a state-differentiating level and with the so called determinization of a finite – automaton model.
Power System Stabilizer Driven by an Adaptive Fuzzy Set for Better Dynamic Performance
Authors: Soliman H. F. , Attia A.-F. , Hellal M. , Badr M. A. L.
Published: March 2021

This paper presents a novel application of a fuzzy logic controller (FLC) driven by an adaptive fuzzy set (AFS) for a power system stabilizer (PSS).The proposed FLC, driven by AFS, is compared with a classical FLC, driven by a fixed fuzzy set (FFS). Both FLC algorithms use the speed error and its rate of change as input vectors. A single generator equipped with FLC-PSS and connected to an infinite bus bar through double transmission lines is considered. Both FLCs, using AFS and FFS, are simulated and tested when the system is subjected to different step changes in the reference value. The simulation results of the proposed FLC, using the adaptive fuzzy set, give a better dynamic response of the overall system by improving the damping coefficient and decreasing the rise time and settling time compared with classical FLC using FFS. The proposed FLC using AFS also reduces the computational time of the FLC as the number of rules is reduced.
System for 3D Visualization of Flaws for Eddy Current Inspection
Authors: Dočekal A. , Kreidl M. , Šmíd R.
Published: March 2021

This paper presents a novel method for 3D visualization of flaws detected during Eddy Current (EC) inspection. The EC data was acquired using an automated scanning system equipped with precise eddy current probe positioning. The method was tested on a single frequency instrument with an absolute probe. The EC inspection procedure is implemented statically by registering the operating point of the instrument at each equidistant point on a tested object.The paper describes a data processing method based on the Fourier transform enabling 3D visualization of flaws. This three-dimensional image of the result of a scan enables the position of flaws to be determined, and the size and bevel (angle to the surface) of each detected flaw to be estimated. This research investigated flaws rising from the surface of the tested object, and flaw depth was not evaluated in this work. This method of visualization is simple to implement and is currently targeted for application in EC scanning devices.
Reconstruction of the Old Bridge of Mostar
Authors: Popovac M.
Published: March 2021

The Old Bridge of Mostar was built in 1566 by Hajrudin, a student of Kodza Mimar Sinan, the greatest Ottoman architect. It is a stone bridge of very slender and elegant shapes: its profile and its skyline are so thin and so high over the river waters that it is hard to believe that such a structure could be made out of huge stone blocks. The Bridge was destroyed in November 1993 by shelling during the recent war events. Its reconstruction was one of the biggest and most complicated projects involving UNESCO, The World Bank and many local and international experts. The task was to build a New Old Bridge – precisely the same in all details as the Old one. After many studies, tests and shape determinations, the project was completed and the actual reconstruction work could begin. Ancient techniques and methods, original materials and a perfectly reconstructed shape gave this Bridge its new life in post-war Mostar.
Metal Fatigue Features
Authors: Brož P.
Published: March 2021

This paper presents a summary of fatigue, crack initiation and growth, and fractographic findings for metal materials. The purpose of this paper is to consolidate and summarize some aspects of the fatigue of materials and structures.
A business process model as a starting point for tight cooperation among organizations
Authors: Mysliveček O.
Published: March 2021

Outsourcing and other kinds of tight cooperation among organizations are more and more necessary for success on all markets (markets of high technology products are particularly influenced). Thus it is important for companies to be able to effectively set up all kinds of cooperation. A business process model (BPM) is a suitable starting point for this future cooperation. In this paper the process of setting up such cooperation is outlined, as well as why it is important for business success.
Microwave Drying of Textile Materials and Optimization of a Resonant Applicator
Authors: Pourová M. , Vrba J.
Published: March 2021

The principal aim of this work was to design and optimize the applicator for microwave drying. Our applicator is derived from the Fabry-Perrot resonator, which is an open type resonator.The whole system works at frequency 2.45 GHz and the magnetron that we used delivers power 800 W. This machine is intended for use in drying in factory production of fabrics. After identifying of the basic arrangement of the microwave drying machine, the next step in the design was the use of the electromagnetic field simulator. We determined the position of the magnetron and found the distribution of the electric field strength in drying textiles in this way. In parallel, we analyzed the drying system with analytical calculations. We created a diagram of the EM waves inside this structure and reached the resulting expression for use in calculating the strenght of the electric field in the plane of the drying textile. This quantity depends on the electrical characteristics of wet textiles, e.g. the permittivity and the loss factor. Measurements of these dielectric properties for the coburg is complicated, and this method makes it possible to solve our problem with dielectric parameters. We have SAR distribution results (by simulation and also by measurement), results of measurements of the moisture content in the dried textile with respect to time. These results are important for subsequent optimization of the efficiency of the whole machine.
Extraction of Alkali Ions Investigated by Conductometric and pH Measurements
Authors: Kalvoda L. , Klepáček R.
Published: March 2021

Extraction of alkali ions from aqueous solutions of chlorides and hydroxides into a lipophilic liquid membrane composed of tetraethyl p-tert-butylcalix[4]arene tetraacetate (TBT) solution in hexane was investigated by means of measurements of changes in the electrolytic conductivity and pH-value of the aqueous solution. Hydrolysis of the TBT ionophore resulting in the release of the ethyl groups was proposed as the main reaction process, leading to disturbance of the known preference of TBT for sodium ions.
Indirect Determination of the Risk of Transportation Projects
Authors: Pastor O.
Published: March 2021

This paper deals with indirect determination of the risk of transportation projects. It focuses on cases when the project has certain characteristics that might lead to conclusions concerning the degree of risk. The author proposes a multi-criterion evaluation of the territory with respect to its time evolution in order to determine the characteristics. The proposed method enables a simple graphical representation of the achievement of the territorial evolution in each time section, and also in the entire period that is under consideration. The method presents an inverse characteristic of the risk of the project.
Support for Expert Estimations in Transportation Projects
Authors: Pastor O. , Novotný P. , Melechovský J.
Published: March 2021

This paper deals with risk analysis as a part of the financial assessment of transportation projects. Two approaches to risk assessment are discussed. A risk can be evaluated either directly in terms of the probabilistic distribution of the assessment criterion; or an indirect determination of the risk can be applied without constructing the probability distribution, but by determining the characteristic features of the project.
Functional Determinants for Radially Separable Partial Differential Operators
Authors: Dunne G. V.
Published: March 2021

Functional determinants of differential operators play a prominent role in many fields of theoretical and mathematical physics, ranging from condensed matter physics, to atomic, molecular and particle physics. They are, however, difficult to compute reliably in non-trivial cases. In one dimensional problems (i.e. functional determinants of ordinary differential operators), a classic result of Gel’fand and Yaglom greatly simplifies the computation of functional determinants. Here I report some recent progress in extending this approach to higher dimensions (i.e., functional determinants of partial differential operators), with applications in quantum field theory.
Effective Data Mining for a Transportation Information System
Authors: Haluzová P.
Published: March 2021

This paper describes the application of data mining methods in the database of the DORIS transportation information system, currently used by the Prague Public Transit Company. The goal is to create knowledge about the behavior of objects within this information system. Data is analyzed partly with the help of descriptive statistical methods, and partly with the help of association rules, which may discover common combinations of attributes that occur most frequently within a given data set. Two types of quantifiers were used when creating the association rules; namely “founded implication” and “above average”. The results of the analysis are presented in the form of graphs and hypotheses.
PT-symmetry and Non-Central Potentials
Authors: Lévai G.
Published: March 2021

We present a general procedure by which solvable non-central potentials can be obtained in 2 and 3 dimensions by the separation of the angular and radial variables. The method is applied to generate solvable non-central PT-symmetric potentials in polar coordinates. General considerations are presented concerning the PT transformation properties of the eigenfunctions, their pseudo-norm and the nature of the energy eigenvalues. It is shown that within the present framework the spontaneous breakdown of PT symmetry can be implemented only in two dimensions.
Lectures on Classical Integrable Systems and Gauge Field Theories
Authors: Olshanetsky M.
Published: March 2021

In these lectures we consider Hitchin integrable systems and their relations with the self-duality equations and twisted super-symmetric Yang-Mills theory in four dimension. We define the Symplectic Hecke correspondence between different integrable systems. As an example we consider Elliptic Calogero-Moser system and integrable Euler-Arnold top on coadjoint orbits of the group GL(N, C) and explain the Symplectic Hecke correspondence for these systems.
Robust Detection of Point Correspondences in Stereo Images
Authors: Stojanovic A. , Unger M.
Published: March 2021

A major challenge in 3D reconstruction is the computation of the fundamental matrix. Automatic computation from uncalibrated image pairs is performed from point correspondences. Due to imprecision and wrong correspondences, only an approximation of the true fundamental matrix can be computed. The quality of the fundamental matrix strongly depends on the location and number of point correspondences.Furthermore, the fundamental matrix is the only geometric constraint between two uncalibrated views, and hence it can be used for the detection of wrong point correspondences. This property is used by current algorithms like RANSAC, which computes the fundamental matrix from a restricted set of point correspondences. In most cases, not only wrong correspondences are disregarded, but also correct ones, which is due to the criterion used to eliminate outliers. In this context, a new criterion preserving a maximum of correct correspondences would be useful.In this paper we introduce a novel criterion for outlier elimination based on a probabilistic approach. The enhanced set of correspondences may be important for further computation towards a 3D reconstruction of the scene.
Correlation Functions for Lattice Integrable Models
Authors: Smirnov F.
Published: March 2021

In this lectures I consider the problem of calculating the correlation functions for XXZ spin chain. First, I explain in details the free fermion case. Then I show that for generic coupling constant the fermionic operators acting on the space of quasi-local fields can be introduced. In the basis generated by these fermionic operators the correlation functions are given by determinants as in the free fermion case.
Negative Chromatic Dispersion Generated by Introducing Curvature into Photonic Crystal Fiber
Authors: Lucki M.
Published: March 2021

This is a modeling work, which aims to show that negative chromatic dispersion (CD) may be obtained in a PCF by fiber bending. Results from the study of negative dispersion could be employed in a new dispersion compensating technique. The proposed method does not require doping in the core, and does not require external cores. The minimum negative dispersion achieved by this method was -185000 ps/nm/km. Problems of bending losses and sensitivity of the dispersion with respect to deviations of geometry were studied.
The Influence of PZT Actuators Positioning in Active Structural Acoustic Control
Authors: Švec P. , Jandák V.
Published: March 2021

This paper deals with the effect of secondary actuator positioning in an active structural acoustics control (ASAC) experiment. The ASAC approach is based on minimizing the sound radiation from structures to the far field by controlling the structural vibrations. In this article a rectangular steel plate structure was assumed with one secondary actuator attached to it. As a secondary actuator, a specially designed piezoelectric stripe actuator was used. We studied the effect of the position of the actuator on the pattern and on the radiated sound field of the structural vibration, with and without active control. The total radiated power was also measured. The experimental data was confronted with the results obtained by a numerical solution of the mathematical model used. For the solution, the finite element method in the ANSYS software package was used.
Computer Controlled Switching Device for Deep Brain Stimulation
Authors: Tauchmanová J.
Published: March 2021

This paper has two goals. The practical part deals with the design of a computer controlled switching device for an external stimulator for deep brain stimulation. The switching device is used during investigations with functional magnetic resonance for controlling signals leading to the deep brain stimulation (DBS) electrode in the patient's brain. The motivation for designing this device was improve measured data quality and to enable new types of experiments.The theoretical part reports on early attempts to approach the problem of modeling and localizing the neural response of the human brain as a system identification and estimation task. The parametric identification method and real fMRI data are used for modeling the hemodynamic response.The project is in cooperation with 1st Faculty of Medicine, Charles University in Prague and Na Homolce hospital in Prague.
A Proportional Integral Derivative (PID) Feedback Control without a Subsidiary Speed Loop
Authors: Aboelhassan M.
Published: March 2021

The aim of this investigation is to design and describe the essential features of a brushless direct-current (BLDC) motor. The static and dynamical state of the BLDC-Motor is designed and calculated.Within this frame-work, it has been shown that while working with the P-controller in conjunction with the subsidiary speed loop and PD-controller (with non-zero error in a steady state) without a subsidiary speed loop, there is PID-controller without a subsidiary speed loop which has zero error in a steady state. The last part of this paper is dedicated to a simulation of the circle rounds of P and PID controllers with and without a subsidiary speed loop in MATLAB–SIMULINK to decide which of these controllers is suitable, available and reliable with a BLDC-Motor and their application in cutting tool machines in general.