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Number of results: 47
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Abstract

We examine new mechanisms that introduce environmentally friendly eco-changes involving the elimination of noxious commodities and take into account the structure of demand without a detrimental effect to agents' position. In the era of the fourth industrial revolution, these mechanisms allow eliminating unnecessary services or goods that are being replaced by modern technologies. We define optimal mechanisms under the criterion of distance minimization, when a small number of detrimental commodities is excluded from production processes as well as when producers are change-averse. The results have the form of theorems with rigorous proofs.
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Authors and Affiliations

Agnieszka Lipieta
1
Anna Denkowska
1

  1. Cracow University of Economics, Poland
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Abstract

This paper presents the current stage of the development of EA-MOSGWA – a tool for identifying causal genes in Genome Wide Association Studies (GWAS). The main goal of GWAS is to identify chromosomal regions which are associated with a particular disease (e.g. diabetes, cancer) or with some quantitative trait (e.g height or blood pressure). To this end hundreds of thousands of Single Nucleotide Polymorphisms (SNP) are genotyped. One is then interested to identify as many SNPs as possible which are associated with the trait in question, while at the same time minimizing the number of false detections.

The software package MOSGWA allows to detect SNPs via variable selection using the criterion mBIC2, a modified version of the Schwarz Bayesian Information Criterion. MOSGWA tries to minimize mBIC2 using some stepwise selection methods, whereas EA-MOSGWA applies some advanced evolutionary algorithms to achieve the same goal. We present results from an extensive simulation study where we compare the performance of EA-MOSGWA when using different parameter settings. We also consider using a clustering procedure to relax the multiple testing correction in mBIC2. Finally we compare results from EA-MOSGWA with the original stepwise search from MOSGWA, and show that the newly proposed algorithm has good properties in terms of minimizing the mBIC2 criterion, as well as in minimizing the misclassification rate of detected SNPs.

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Authors and Affiliations

Artur Gola
Małgorzata Bogdan
Florian Frommlet
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Abstract

Implementation of European directives is closely related to the quality of production and the associated operational safety, maintenance of machines and mechanical systems, both mobile or stationary, in order to reduce the dynamic load (vibration and noise) on the working environment, not only during their operating state but also during their design, production, and setting of the vibration isolation components. Reducing the dynamic load of mechanical systems and their components is reflected in the working environment by reduced emissions and immissions of noise and vibration. The presented paper investigates the methods and conditions for noise and vibration control, focusing mainly on increasing the quality of rotating machine components, such as bearings by means of effective vibration isolation of the machines. The solution of this problem requires theoretical analysis and methodology for the measurement of the mechanical systems involved. The results of the vibroacoustic measurements were analysed in terms of the low frequency vibration and noise level (quality) of bearings and conditions for effective vibration isolation of the machines using vibroacoustic diagnostic method. Furthermore, the impact on the working environment was also analysed. Finally, the paper suggests some actions to be taken to effectively reduce the unwanted vibrosound energy in working places, also using recycled material as a vibration isolation element.

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Authors and Affiliations

Stanislav Žiaran
Ľubomír Šooš
Ondrej Chlebo
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Abstract

The green peach aphid, Myzus persicae (Sulzer), is a polyphagous and holocyclic aphid which significantly damages agricultural crops. In the current study, the effects of micronutrients on some secondary metabolites of bell pepper (Capsicum annum L.) leaves and their subsequent influence on the life table parameters of M. persicae were investigated under greenhouse conditions. The flavonoid content in bell pepper leaves significantly changed following micronutrient treatments in the wavelength of 270 nm while there were no significant differences in the wavelengths 300 and 330 nm. The highest anthocyanin content was recorded after Fe treatment (3.811 mg ⋅ ml–1) while the total phenolic content in the bell pepper leaves increased after Mn (541.2 mg ⋅ ml–1) treatment compared to Fe (254.5 mg ⋅ ml–1) and control (216.33 mg ⋅ ml–1), respectively. The highest values of intrinsic (r) and finite rates of population increase (λ) of M. persicae were gained with Zn (0.320 and 1.377 day–1, respectively) treatment although the highest and the lowest values of the mean generation time (T) were found with Fe and Zn (14.07 and 12.63 days, respectively) treatments, respectively. Our findings suggest that Mn, more than Zn micronutrients, decreased ecological fitness of green peach aphid and may help enhance the efficiency of pest control techniques.

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Authors and Affiliations

Tayebeh Alizamani
Jahanshir Shakarami
Mozhgan Mardani-Talaee
Arash Zibaee
Jose Eduardo Serrão
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Abstract

Postharvest insect pests constitute major threats to food security because they cause qualitative and quantitative damage to agricultural produce. Therefore, eco-friendly and cost-effective measures should be used for their management. In this study, five botanical powders ( Trema orientalis and Crataeva religiosa leaves; and Citrus tangelo, Citrus maxima and Citrus aurantifolia peels) were admixed with Spintor® [1.25 active ingredient (a.i.) mg · kg –1] and evaluated as toxicants against Tribolium castaneum. Each botanical powder and spintor was solely applied at 1000 mg · kg –1 millet seeds. Spintor-botanical powder mixtures admixed at a ratio of 1 : 1 (w/w) were applied at 500 and 1000 mg · kg –1, corresponding to 0.313 and 0.625 a. i. mg · kg –1 for spintor in the mixtures, respectively. On the 14th day of exposure, the Citrus species admixed with spintor and applied at 500 mg · kg –1 evoked significantly (p < 0.05) higher percentage mortality (72.22–90.28%) than what was observed in the mixture of spintor with T. orientalis (22.08%) or the mixture of spintor with C. religosa (17.92%) applied at 500 mg · kg –1. There was a significant difference (p < 0.05) in the Kaplan-Meier estimates of the treatments against the insects. The time required to kill 50% of the assayed insects (LT50) when Citrus species were admixed with spintor at 500 mg · kg –1 (10 days) was shorter than 14 days observed in the mixture of spintor with T. orientalis or C. religiosa. Therefore, admixing spintor with any of the Citrus powders [at 1 : 1 (w/w)] applied at 500 mg · kg –1 seed is recommended for the protection of millet seeds against T. castaneum.,
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Authors and Affiliations

Oludele Ajiboye
1
Samuel Adelani Babarinde
1
ORCID: ORCID
Gabriel Olulakin Adesina
1
Oludayo Christopher Olusoji
2
Timothy Abiodun Adebayo
1
Kasali Amofe Adelasoye
1

  1. Department of Crop and Environmental Protection, Ladoke Akintola University of Technology, Ogbomoso, Nigeria
  2. Fruit Improvement Unit, National Horticultural Research Institute, Ibadan, Nigeria
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Abstract

The electron field and photo-field emission from GaN nanostructures has been analyzed in this review. In order to explain the obtained experimental results, a model was proposed taking into account the change in carrier concentration distribution in the main and the satellite valley during the emission process. The lowering of work function (due to the increased number of carriers in the satellite valley) can explain the decrease in the Fowler-Nordheim plot slope. It was shown that the energy difference between the main and satellite valley in GaN was decreased in the case of quantum confinement, thus increasing the probability of electron transition from Γ to X valley at same electric fields.

Investigations of electron photo-field emission demonstrated that the Fowler–Nordheim plots of the emission current have different slopes for nonilluminated and illuminated devices. A model based on the electron emission from valleys having different specific electron affinities is proposed to explain the experimental results. In the absence of illumination the emission takes place only from the lower valley. Upon UV illumination and presence of a high electric field at the emitter tip, the upper valley of the conduction band appears to be occupied by electrons generated at the valence band.

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Authors and Affiliations

V. Litovchenko
A. Evtukh
A. Grygoriev
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Abstract

The objective of the study was to trace the variability of the hydrochemical conditions in three lakes of the West Pomeranian Voivodeship (Poland) – Starzyca, Maszewskie and Nowogardzkie in the annual cycle. The research was done in 2018–2019, and samples for analysis were collected 4 times a year. All analyses were performed applying standard methods. Such hydrochemical indices were determined as dissolved oxygen, chemical oxygen demand, content of orthophosphates, total phosphorus, nitrite, nitrate, ammonium, chlorophyll a and iron. The study showed that all lakes in the research cycle were characterised by a polymictic type of water mixing, and the trophic level, based on the adopted criteria, indicated advanced eutrophy, which may also be caused by anthropogenic pressure. Oxygen conditions characterised by deoxidation of the waters in the bottom layer in the spring and summer seasons, and clear oxygenation in the surface water layer (in Lake Maszewskie reaching even 188.5% in the spring) confirm the significant advancement of the eutrophication process. The supply of phosphorus and nitrogen in spring from pelagic waters in the waters of the examined lakes influences concentrations of chlorophyll a in the summer. The influence of “internal supply” (bottom waters and bottom sediments) on the amount of nutrients available for autotrophs is clearly visible in the analysed lakes – an increase in nitrogen and mineral phosphorus concentrations in relation to surface waters was observed in the bottom layer.
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Authors and Affiliations

Agnieszka Tórz
1
ORCID: ORCID
Małgorzata Bonisławska
1
ORCID: ORCID
Arkadiusz Nędzarek
1
ORCID: ORCID
Agnieszka Rybczyk
1
ORCID: ORCID
Adam Tański
1
ORCID: ORCID

  1. West Pomeranian University of Technology, Faculty of Food Sciences and Fisheries, Królewicza Kazimierza St, 4, 71-550 Szczecin, Poland
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Abstract

Edible snails are kept in farms in many countries worldwide. As farm animals, they are an object of interest of veterinary studies and applied biology. There is a large demand for tests which would help identify their health and well-being. The objective of this study was to assess the usefulness of determining the concentration of urea in hemolymph as a marker of health of the Lissachatina fulica and Cornu aspersum edible snails. The observation covered snails from four farms marked from A to D, in which numerous deaths (farm A) and decreased body weight gain (farms B and C) were observed. In experimental farm D we observed a group of snails subjected to stress and a control group maintained in correct conditions. High concentrations of urea were found in the hemolymph of all farm animals from farms A, B and C, as well as in those subjected to food deprivation in farm D (on average from 96 mg/dl in farm D to 320 mg/dl in farm A). On the other hand, in controls from group D, the concentration of the parameter in question was much lower (< 2.0 mg/dl). The results obtained indicate that the urea concentration is a non-specific marker of pathological conditions in snails, and that the continuous monitoring of this parameter makes it possible to demonstrate irregularities in farming and introduce appro- priate and early measures to eliminate such disturbances.

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Authors and Affiliations

J. Ziętek
L. Guz
A. Wójcik
ORCID: ORCID
S. Winiarczyk
Ł. Adaszek
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Abstract

The article presents the results of CRL research on glacial till contaminated with JET A1 aviation fuel and mineral oil 15W40. The conducted research has shown that the compressibility of fine grained soils contaminated with hydrocarbons during a constant rate of loading tests depends on the physical properties of the soil, properties of oil contaminants, their content in the soil pores as well as the adopted loading velocity. The implemented laboratory test program shows that the contamination of glacial till with hydrocarbons increases their compressibility. Moreover, this research shows that the CRL test method may be recommended in the compressibility research of fine grained soils contaminated with hydrocarbons.
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Authors and Affiliations

Piotr Stajszczak
1

  1. Geoteko Geotechnical Consultants Ltd., ul. Wałbrzyska 14/16, 02-739 Warszawa, Poland
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Abstract

The purpose of this paper is to examine two hypothetical models: one in which job satisfaction acts as a mediator of the effects of overqualification on turnover intention and performance, and another in which job satisfaction acts as a mediator of the effects of overqualification on performance. Data were collected from 318 call center employees in Portugal. The relationships were tested using a multiple regression hierarchy with PROCESS. As hypothesized, job satisfaction mediates the relationship between overqualification and turnover intentions. It appears that overqualification alone does not influence intention to quit, but rather does so via satisfaction. Job satisfaction also mediates the relationship between overqualification and job performance. However, perceptions of non-growth appear to be associated with a decline in contextual performance. The effects of overqualification on turnover intentions and job performance of call center employees have not been previously studied. Therefore, this study aims to fill this gap. Our study joins the small number of studies that analyze the mechanisms explaining the relationship between this mismatch between job demands and employees' perceived education, skills, experience, and work outcomes.
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Authors and Affiliations

Luís Andrade
1
ORCID: ORCID
Claúdia Santos
1
Liliana Faria
2
ORCID: ORCID

  1. Universidade Europeia, Lisbon, Portugal
  2. University of Algarve, Faro, Portugal
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Abstract

In this contribution, an overview over a numerical scheme for the crack modelling of spruce wood under tensile loading is given. A material model for biaxially stressed spruce wood with consideration of the effect of knots on the strength properties has been developed. A necessary feature of this material model is its ability to treat cracks by means of the so-called smeared crack concept. For this reason the consideration of a so-called characteristic length in the corresponding evolution laws of the strength values is required. The successful implementation in the material model is shown by means of various numerical examples.
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Authors and Affiliations

Herbert W. Mulllner
Christoph Kohlhauser
Martin Fleischmann
Josef Eberhardsteiner
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Abstract

Resilient under sleeper pads (USPs) are vibration isolators used in the ballasted track structure to improve the dynamic performance of the track, reduce vibrations and protect the ballast layer. Being permanently connected with the rail supports (sleepers or turnout bearers), the pads must exhibit a proper value of the pull-off strength, which ensures that they do not separate from the supports while being transported to the construction site or during many years of exploitation. This study focuses on the experimental determination of the pull-off strength of USPs attached to full scale prestressed concrete sleepers. Three variants are tested: two pads equipped with different anchor layers attached to the sleepers in the production plant and one pad glued to the sleeper in the laboratory. Some of the tested USPs are made of recycled styrene-butadiene rubber (SBR). An important part of the work is specification of the requirements for the pull-off strength of USPs, as well as the requirements for sleepers and turnout bearers equipped with resilient pads.
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Authors and Affiliations

Cezary Kraskiewicz
1
ORCID: ORCID
Artur Zbiciak
1
ORCID: ORCID
Henryk Zobel
1
ORCID: ORCID
Anna Al Sabouni-Zawadzka
1
ORCID: ORCID

  1. Warsaw University of Technology, Faculty of Civil Engineering, Al. Armii Ludowej 16, 00-637 Warsaw
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Abstract

Solar radiation reflectance was analysed to characterize Arctic ornithogenic tundra developing in the vicinity of large breeding colony of Brunnich‘s guillemots Uria lomvia and kittiwakes Rissa tridactyla at the foot of Gnĺlberget cliff (Hornsund, SW Spitsbergen). Radiometric method was found to be a useful tool for studying structure and functioning of plant formations. We measured reflectance of four wavelengths: 554 nm (YG), 655 nm (RED), 870 nm (NIR) and 1650 nm (SWIR) at 10 plots situated along the transect running from the colony to the sea. Moreover, data of plant community character, species quantitative composition as well as total biomass were collected to relate these parameters with the spectral values. The results showed that radiometric data characterized vegetation well enough to recognize the same plant communities on the basis of spectral reflectance as distinguished with traditional phytosociological methods.

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Authors and Affiliations

Katarzyna Zmudczyńska
Adrian Zwolicki
Mateusz Barcikowski
Adam Barcikowski
Lech Stempniewicz
ORCID: ORCID
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Abstract

This article is devoted to the official forms in the inflection of chosen toponyms in Poland and the variety of dialectal singular and plural place names. The variety of place names often diverges from the rules of language use, and causes language users problems. The toponyms have peculiar, locally used inflected forms; the outside-linguistic (non-linguistic) factors that are social and local factors, play an important role in the inflection of place names. The local population often uses other forms than those recommended by official sources. I focus my attention on the genitive forms of toponyms because it is mainly here that one can see clear variations in the official and local inflection of place names. The material shows that the singular masculine toponyms have genitive endings: -a (in the official variety), -u (in the local variety), for example Biłgoraj, gen. Biłgoraja, but in the local dialect: biłgoraju. The singular feminine place names have genitive endings: -ej (in the official variety), -y||-i (in the local variety): Brzezowa, gen. Brzezowej, but Brzezowy in the local dialect. The plural toponyms have genitive endings: -ø, -ów, -i (-y), but in the local circulation the ending -ów is dominant and demonstrates a wider expansion in use. For example Brzózki, gen. Brzózek, in the local variety Brzuskuf; Budy, official gen. Bud, but Buduf; Burnie, gen. Burni, in the local dialect: Burniuf. The gathered material reflects a hesitation in the inflection of toponyms, as the linguistic customs and presented dialectal records of forms of genit ives of place names show a significantly diverse approach towards the Polish language.

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Authors and Affiliations

Iwona Nobis
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Abstract

This paper addresses issues of feminism, masculinity, and the emotional culture of middle-class men who self-declare as feminists. The author discusses feminist theories on masculinity and its relations with femininity, critical theories of masculinity, and the role of emotional culture in the expression of masculinity. Feminists have proposed a dimorphic definition of feminism as a political movement and personal attitude critical of masculine domination. The critique of patriarchal, hegemonic masculinity has led feminists either to identify with “positive” masculinity or to reject masculinity for a post-gender narrative or material-discursive fact of “being a man,” which suggests an inadequacy of the sex/gender distinction in the description of gender identity. The identification with feminism allows men to avoid the crisis of traditional masculinity and the perspective of gendered emotions, as well as to gain insight into gendered determinants of emotional expression.

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Authors and Affiliations

Paweł Bagiński
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Abstract

The main goal of this paper is to propose the probabilistic description of cyclical (business) fluctuations. We generalize a fixed deterministic cycle model by incorporating the time-varying amplitude. More specifically, we assume that the mean function of cyclical fluctuations depends on unknown frequencies (related to the lengths of the cyclical fluctuations) in a similar way to the almost periodic mean function in a fixed deterministic cycle, while the assumption concerning constant amplitude is relaxed. We assume that the amplitude associated with a given frequency is time-varying and is a spline function. Finally, using a Bayesian approach and under standard prior assumptions, we obtain the explicit marginal posterior distribution for the vector of frequency parameters. In our empirical analysis, we consider the monthly industrial production in most European countries. Based on the highest marginal data density value, we choose the best model to describe the considered growth cycle. In most cases, data support the model with a time-varying amplitude. In addition, the expectation of the posterior distribution of the deterministic cycle for the considered growth cycles has similar dynamics to cycles extracted by standard bandpass filtration methods.

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Authors and Affiliations

Łukasz Lenart
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Abstract

This paper presents an improved approach for locating and identifying faults for UHV overhead Transmission line by using GA-ANFIS. The proposed method uses one end data to identify the fault location. The ANFIS can be viewed either as a Fuzzy system, neural network or fuzzy neural network FNN. The integration with neural technology enhances fuzzy logic system on learning capabilities are proposed to analyze the UHV system under different fault conditions. The performance variation of two controllers in finding fault location is analyzed. This paper analyses various faults under different conditions in an UHV using Matlab/simulink. The proposed method is evaluated under different fault conditions such as fault inception angle, fault resistance and fault distance. Simulation results confirm that the proposed method can be used as an efficient for accurate fault location on the transmission line.

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Authors and Affiliations

G. Banu
S. Suja
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Abstract

The article describes the testing of four selected samples of limestone originating from four commercially exploited deposits. The tests of sorbents included a physicochemical analysis and calcination in different atmospheres. The main aim of the tests was to determine the possibilities for using limestone during combustion in oxygen-enriched atmospheres. Tests in a synthetic flue gas composition make it possible to assess the possibility of CaCO3 decomposition in atmospheres with an increased CO2 concentration.

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Authors and Affiliations

Angelika Kochel
Aleksandra Cieplińska
Arkadiusz Szymanek
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Abstract

The aim of this article is to present a modern method of convective drying intensification caused by the external action of ultrasound. The purpose of this study is to discover the mechanism of ultrasonic interaction between the solid skeleton and the moisture in pores. This knowledge may help to explain the enhancement of drying mechanism affected by ultrasound, particularly with respect to biological products like fruits and vegetables. The experimental kinetics tests were conducted in a hybrid dryer equipped with a new ultrasonic generator. The drying kinetics curves determined on the basis of drying model developed by the author were validated with those by the ones obtained from experimental tests. The intensification of heat and mass transfer processes due to ultrasound induced heating effect and vibration effect are analysed. The obtained results allow to state that ultrasound makes drying processes more effective and enhance the drying efficiency of biological products without significant elevation of their temperature.

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Authors and Affiliations

Stefan Jan Kowalski
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Abstract

Simulations of turbulent mixing in two types of jet mixers were carried out using two CFD models, large eddy simulation and κ-ε model. Modelling approaches were compared with experimental data obtained by the application of particle image velocimetry and planar laser-induced fluorescence methods. Measured local microstructures of fluid velocity and inert tracer concentration can be used for direct validation of numerical simulations. Presented results show that for higher tested values of jet Reynolds number both models are in good agreement with the experiments. Differences between models were observed for lower Reynolds numbers when the effects of large scale inhomogeneity are important.

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Authors and Affiliations

Krzysztof Wojtas
Łukasz Makowski
Wojciech Orciuch
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Abstract

Preliminary lab-scale investigations were conducted on slagging abatement in biomass-firing by fuel mixing. Three agriculture biomass fuels and olive cake were used in the experiments. Polish lignites and bituminous coals were examined as anti-sintering additives. The effects of chlorine release, potassium retention and ash sintering were examined by heating samples of biomass fuels and additives in the muffle oven and, next, firing them in the laboratory down-fired furnace at the temperature in the range of 800-1150ºC. The obtained slag samples were analysed on: chlorine and potassium content, sintering tendency and crystalline components. Among the examined coals lignite from Turów mine and bituminous coal from Bolesław Śmiały mine appeared to be the most effective in potassium retention in aluminosilicate and chlorine release from slag. Possibly the major factor of these coals which reduced ash sintering was relatively high content of kaolinite

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Authors and Affiliations

Włodzimierz K. Kordylewski
Krzysztof J. Mościcki
Karol J. Witkowski
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Abstract

Correct incipient identification of an analog circuit fault is conducive to the health of the analog circuit, yet very difficult. In this paper, a novel approach to analog circuit incipient fault identification is presented. Time responses are acquired by sampling outputs of the circuits under test, and then the responses are decomposed by the wavelet transform in order to generate energy features. Afterwards, lower-dimensional features are produced through the kernel entropy component analysis as samples for training and testing a one-against-one least squares support vector machine. Simulations of the incipient fault diagnosis for a Sallen-Key band-pass filter and a two-stage four-op-amp bi-quad low-pass filter demonstrate the diagnosing procedure of the proposed approach, and also reveal that the proposed approach has higher diagnosis accuracy than the referenced methods.
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Authors and Affiliations

Chaolong Zhang
Yigang He
Lei Zuo
Jinping Wang
Wei He

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