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Number of results: 29
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Abstract

The multicriteria decision process consists of five main steps: definition of the optimisation problem, determination of the weight structure of the decision criteria, design of the evaluation matrix, selection of the optimal evaluation method and ranking of solutions. It is often difficult to obtain the optimal solution to a multicriterion problem. The main reason is the subjective element of the model – the weight functions of the decision criteria. Expert opinions are usually taken into account in their determination. The aim of this article is to present a novel method of minimizing the uncertainty of the weights of the decision criteria using Monte Carlo simulation and method of data reconciliation. The proposed method is illustrated by the example of multicriterion social effectiveness evaluation for electric power supply to a building using renewable energy sources.
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Authors and Affiliations

Barbara Mendecka
Joachim Kozioł
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Abstract

An analysis of energy efficiency for transcritical compression unit with CO2 (R744) as the refrigerant has been carried out using empirical operating characteristics for the two-phase ejector. The first stage of the refrigerant compression is carried out in the ejector. The criterion adopted for the estimation of energy efficiency for the cycle is the coefficient of performance COP. The analysis is performed for the heat pump and refrigeration systems. The results of COP for the systems with the ejector has been compared with the COPL values for the single stage Linde cycle.

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Authors and Affiliations

Joachim Kozioł
Wiesław Gazda
Łukasz Wilżyński
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Abstract

It is assumed in the paper that the signals in the enclosure in a transient period are similar to a noise induced by vehicles, tracks, cars, etc. passing by. The components of such signals usually points out specific dynamic processes running during the observation or measurements. In order to choose the best method of analysis of these phenomena, an acoustic field in a closed space with a sound source inside is created. Acoustic modes of this space influence the sound field. Analytically, the modal analyses describe the above mentioned phenomena. The experimental measurements were conducted in the room that might comprise the closed space with known boundary conditions and the sound source Brüel & Kjær Omni-directional type 4292 inside. To record sound signals before the field's steady state was reached, the microphone type 4349 and the 4-channel frontend 3590 had been used. The obtained signals have been analysed by using two approaches, i.e. Fourier and the wavelet analysis, with the emphasis on their efficiency and the capability to recognise important details of the signal. The results obtained for the enclosure might lead to the formulation of a methodology for an extended investigation of a rail track or vehicles dynamics.
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Authors and Affiliations

Andrzej Błażejewski
Piotr Kozioł
Maciej Łuczak
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Abstract

The paper presents the analysis of results of the investigations concerning a vertical pipe submersion coefficient h/L with an air-water mixer of the described type. The investigations were performed on an air lift pump testing stand, constructed in a laboratory on a scale of 1:1. At first, the paper presents the possibilities of application of air lift pumps. The investigations to date have been briefly characterized and a research problem formulated. Then the paper describes the construction and working principle of the air lift pump testing stand, constructed in a laboratory. It presents the methodology of derivation of empirical formulas for calculation of vertical pipe submersion coefficients h/L. The comparative analysis of the values of h/L determined in the measurements with the values of h/L calculated using the derived empirical formulas was carried out. The research scope encompassed the derivation of the aforementioned empirical formulas for five fixed values of air lift pump delivery head H, comparison of the obtained values h/L determined in the measurements with the values of h/L calculated using the derived empirical formulas and the improved analytical Stenning-Martin model. To derive the empirical formulas for calculation of the vertical pipe submersion coefficient h/L, the dimensional analysis and multiple regression was applied. The investigations of the vertical pipe submersion coefficient h/L were carried out for the vertical pipe internal diameter d = 0.04 m and for the fixed delivery heads H: 0.45, 0.90, 1.35, 1.80, 2.25 m. The values calculated using the derived empirical formulas (23), (24), (25), (26), (27) coincide with the values of h/L determined in the measurements for the whole range of the investigated delivery heads H. On the other hand, the values of h/L calculated using the improved analytical Stenning-Martin model do not coincide with the values of h/L determined in the measurements for the delivery heads H equal 0.45 and 0.90 m, whereas they are comparable for H equal 1.35, 1.80, 2.25 m. For the tested air lift pump with the air-water mixer of the described type (Fig. 2), the maximum air pressure should not exceed pp = 145 kPa, because for higher pressures the water flow rate diminishes. In the air lift pump being tested, the water flow rate Qw grows along with the rise in the air flow rate and in the vertical pipe submersion coefficient h/L whereas falls along with the rise in the delivery head H.
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Authors and Affiliations

M. Kalenik
M. Chalecki
P. Wichowski
A. Kozioł
M. Babych
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Abstract

The article presents research results of physico-chemical and environmental issues for the dust generated during dedusting of the

installation for the processing and preparation of moulding sand with bentonite. Particular attention was paid to the content of heavy

metals and emission of gases from the BTEX group, which is one of the determinants of the moulding sands harmfulness for the

environment. The analysis of heavy metals in the test samples indicate that there is an increase of the content of all metals in the dust

compared to the initial mixture of bentonite. The most significant (almost double) increase observed for zinc is probably related to the

adsorption of this element on the dust surface by contact with the liquid metal. The study showed, that dust contained more than 20% of

the amount of montmorillonite and had a loss on ignition at a similar level. The addition of 1% of dust to the used moulding sand results in

almost 30% increase in the total volume of gases generated in casting processes and nearly 30% increase of the benzene emission.

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Authors and Affiliations

S. Żymankowska-Kumon
B. Grabowska
A. Bobrowski
Ż. Kurleto-Kozioł
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Abstract

The spectroscopic FT-IR and FT-Raman methods allowed to identify the cross-linking process of the aqueous composition of poly(acrylic

acid)/sodium salt of carboxymethyl starch (PAA/CMS-Na) applied as a binder for moulding sands (as a novel group binders BioCo). The

cross-linking was performed by physical agent, applying the UV-radiation. The results of structural studies (IR, Raman) confirm the

overlapping of the process of cross-linking polymer composition PAA/CMS-Na in UV radiation. Taking into account the ingredients and

structure of the polymeric composition can also refer to a curing process in a binder - mineral matrix mixture. In the system of bindermineral

matrix under the influence of ultraviolet radiation is also observed effect of binding. However, the bonding process does not occur

in the entire volume of the investigated system, but only on the surface, which gives some possibilities for application in the use of UV

curing surface of cores, and also to cure sand moulds in 3D printing technology

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Authors and Affiliations

B. Grabowska
A. Bobrowski
K. Kaczmarska
Ż. Kurleto-Kozioł
Ł. Szymański
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Abstract

Temperature change is one of key factors which should be taken into account in logistics during transportation or storage of many types of goods. In this study, a passive UHF RFID-enabled sensor system for elevated temperature (above 58°C) detection has been demonstrated. This system consists of an RFID reader and disposable temperature sensor comprising an UHF antenna, chip and temperature sensitive unit. The UHF antenna was designed and simulated in an IE3D software. The properties of the system were examined depending on the temperature level, type of package which contains the studied objects and the type of antenna substrate.

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Authors and Affiliations

Kamil Janeczek
Małgorzata Jakubowska
Grażyna Kozioł
Piotr Jankowski-Mihułowicz
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Abstract

The increasing demands for miniaturization and better functionality of electronic components and devices have a significant effect on the requirements facing the printed circuit board (PCB) industry. PCB manufactures are driving for producing high density interconnect (HDI) boards at significantly reduced cost and reduced implementation time. The interconnection complexity of the PCB is still growing and today calls for 50/50 μm or 25/25 μm technology are real. Existing technologies are unable to offer acceptable solution. Recently the Laser Direct Imaging (LDI) technology is considered as an answer for these challenges. LDI is a process of imaging electric circuits directly on PCB without the use of a phototool or mask. Our laboratory system for Laser Direct Imaging is designed for tracks and spaces on PCB with minimum width distance of 50/50 μm. In comparison with conventional photolithography method, this technology is much better for 50/50 μm track and spaces. In our research we used photoresist with resolution 50 μm, but in case of using laser photoresists with better resolution (e.g. 25 μm) it will be possible to image tracks in super-fine-line technology (25/25 μm). The comparison between two technology of creating mosaic pattern tracks on PCB proved that laser imaging is promising technology in high density interconnects patterns, which are widely use in multilayered PCB and similar applications.

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Authors and Affiliations

R. Barbucha
M. Kocik
J. Mizeraczyk
G. Kozioł
J. Borecki
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Abstract

Problems concerning structures dynamics are being one of most important subjects in recent investigations associated with railways constructions. The need of modelling of such structures and their behaviour prediction leads to necessity of seeking new approaches, mainly due to highly increasing speeds of vehicles and traffic intensity. Comparative studies carried out on experimental data, measurements and theoretical research show that models based on multi-layered approach supported by semi-analytical approximations of solutions can give new insight into undertaken analyses. More detailed consideration of roads components and their physical properties, along with application of effective estimations allowing to avoid numerical instabilities linked with extremal dynamic variations, can be important tools in obtaining new solutions both, theoretical and engineering. This paper briefly presents a number of multilayer railway track models, with special emphasis on nonlinear track properties. Existing analytical and semi-analytical solution methods are presented with main advantages of new approaches. The theoretical double-beam system with two nonlinear layers is solved and computational examples are presented along with possibility of their transition to other multilayer structures analysis.

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Authors and Affiliations

Piotr Kozioł
Rafał Pilecki
ORCID: ORCID
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Abstract

Objective: Evaluation of serum lactadherin level, its correlation with disease activity and certain biochemical parameters in IBD patients.
Methods: The study involved adult IBD patients, comprising 50 with ulcerative colitis (UC), 68 with Crohn’s disease (CD), and 29 healthy controls.
Results: The MFGE8 median concentration was significantly higher in UC versus controls (1914.54 vs. 1392.21; p = 0.017), but not in CD. The median MFGE8 levels in UC and CD patient groups didn’t significantly differ. There was a significant inverse correlation between MFGE8 and CRP (r = –0.283; p = 0.044) and fibrinogen (r = –0.362, p = 0.017) in UC. In active UC, MFGE8 median concentration was higher versus controls (1974.36 vs. 1392.21; p = 0.04) and negatively correlated with CRP (r = –0.482; p = 0.005), WBC (r = –0.391; p = 0.027), and fibrinogen (r = –0.473; p = 0.015). Inactive UC showed negative correlation only with fibrinogen (r = –0.567; p = 0.018). No correlations were found with disease activity measured using appropriate scales, age, BMI, or gender.
Conclusions: Active UC patients show higher MFGE8 levels. These increase inversely with inflamma-tory markers (CRP, WBC, fibrinogen) in active UC, but not in CD.
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Authors and Affiliations

Kamil Kozioł
1
Danuta Owczarek
1
Dorota Cibor
1
Małgorzata Zwolińska-Wcisło
1

  1. Department of Gastroenterology and Hepatology, Jagiellonian University Medical College, Kraków, Poland
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Abstract

Oxidative stress (OxS) has been implicated in the pathogenesis of Crohn’s disease (CD). The aim of this study was to examine whether nonenzymatic antioxidants are associated with active CD, by using the FRAP and GSH assay in plasma. Additionally, we measured bilirubin and albumin levels as two individual components of the plasma antioxidant system. A total of 55 patients with established CD, 30 with active CD and 25 with inactive disease, and 25 healthy individuals were prospectively enrolled in this study. We evaluated CD activity index, BMI and blood morphology, platelet count, serum CRP level, and bochemical parameters of OxS: ferric reducing ability of plasma (FRAP), reduced glutathione (GSH) in plasma and bilirubin and albumin levels in serum. Plasma FRAP and GSH concentrations were decreased in both CD groups compared to controls and negatively correlated with CDAI values (FRAP: r = –0.572, p = 0.003; GSH: r = –0.761, p = 0.001), CRP and platelet count. Bilirubin and albumin levels were lower in the serum of active CD patients than inactive CD patients and controls and negatively correlated with the CD activity index (r = –0328, p = 0.036, r = –0.518, p = 0.002) and CRP (r = –0.433, p = 0.002). The decreased FRAP and GSH levels in plasma and bilirubin and albumin levels in serum of patients with active CD compared to inactive CD and controls underlines the importance of OxS in the pathophysiology and activity of CD.

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Authors and Affiliations

Katarzyna Szczeklik
Wirginia Krzyściak
Dorota Cibor
Kamil Kozioł
Halina Pocztar
Jolanta Pytko-Polończyk
Tomasz Mach
Danuta Owczarek
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Abstract

This work presents the methodology for analyzing the impact of ground vibrations induced during the drilling of gas/oil exploration wells on the surrounding constructions, as well as on humans and the natural environment. In the primary stage, this methodology is based on measurements of ground vibrations induced by a specific type of drilling system in the so-called reference site. In the next stage, ground vibrations are estimated in similar conditions to another design site, these conditions are assumed for a given drilling system, treated as a vibration source. In both sites, special seismic and geotechnical data are collected to construct numerical models for dynamic analyses. Finally, if it is required, a protection system is proposed with respect to the drilling technology and local conditions. The methodology presented has been tested on the terrain of an active natural gas mine used as the design site, and located in the southeastern part of Poland. The reference site was placed in the terrain of a working drilling system in similar conditions in the central part of Poland. Based on the results of numerical simulations, one may verify the different locations of the drilling rig in the design site with respect to the existing industrial structure. Due to the hazard from destructive ground vibrations, a certain vibroisolation system was proposed at the design site. Based on the results of numerical simulations one could rearrange the components of the drilling system in order to provide maximum security for the surrounding structures.

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Authors and Affiliations

Andrzej Truty
Zenon Pilecki
Krzysztof Stypuła
Rafał Wiśniowski
Krzysztof Kozioł
Stanisław Stryczek
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Abstract

The growth of the global population, urbanization as well as economic and industrial development, affect the continuously increasing demand for mineral aggregates. The current assessed global production of mineral aggregates amounts to 50 billion Mg/year, which statistically approximates 6.5 Mg per an inhabitant of the globe. In terms of consumption volume, water is the only raw material ahead of aggregates. Despite such a great scale, in many countries and regions the extraction and production of aggregates belong to the least regulated sector of human activity. This refers particularly to the countries of A sia, A frica, and North A merica, where both the resources and the extraction of aggregates, particularly of sand and gravels, are either not monitored and registered. It significantly increases the negative impact on the natural environment, due to the destruction of riverbeds and oxbows, coastal erosion, drying up cultivation areas, etc. In the reports, local terminology of aggregates often functions, which makes it difficult to compare them and prepare appropriate balances. In order to regulate the unfavorable situation, one of the main conclusions of the Report (UNEP 2019) is the need of implementing a common requirement to plan and monitor the process of extraction of natural resources. The paper presents the possibility of forecasting the extraction and producing aggregates based on the consumption of cement, i.e. the basic building material. A lthough the analyzed coefficient of mineral aggregate production per unit of cement consumption (production) varies, its advantage is the fact that the production of cement is identified and taken into account in balances of industrial production of the majority of countries, whereas such identification for mineral aggregate production are still lacking.

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Authors and Affiliations

Ireneusz Ryszard Baic
ORCID: ORCID
Wiesław Kozioł
ORCID: ORCID
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Abstract

The electromagnetic field (EMF) is an environmental factor affecting living organisms. The aim of this study was to demonstrate the effect of an extremely low frequency electro- magnetic field (ELF-EMF) on selected chemical components of the honeybee (Apis mellifera L.) using Fourier Transform Infrared (FTIR) spectroscopy. The FTIR method provides information on the chemical structure of compounds through identification and analysis of functional groups. The honeybees were treated with EMF at a frequency of 50 Hz and magnetic induction of 1.6 mT for 2, 6, 12, 24 and 48 hours. Analysis of FTIR spectra showed that EMF exposure longer than 2 hours induced changes in the structure of chemical compounds, especially in the IR region corresponding to DNA, RNA, phospholipids and protein vibrations, compared to control samples (bees not EMF treated). The results confirm the effect of EMF on bees depending on the duration of exposure.

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Authors and Affiliations

A. Koziorowska
J. Depciuch
J. Białek
I. Woś
K. Kozioł
S. Sadło
B. Piechowicz
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Abstract

The intercalation into interlayer spaces of montmorillonite (MMT), obtained from natural calcium bentonite, was investigated. Modification of MMT was performed by the poly(acrylic acid-co-maleic acid) sodium salt (co-MA/AA). Efficiency of modification of MMT by sodium salt co-MA/AA was assessed by the infrared spectroscopic methods (FTIR), X-ray diffraction method (XRD) and spectrophotometry UV-Vis. It was found, that MMT can be relatively simply modified with omitting the preliminary organofilisation – by introducing hydrogel chains of maleic acid-acrylic acid copolymer in a form of sodium salt into interlayer galleries. A successful intercalation by sodium salt of the above mentioned copolymer was confirmed by the powder X-ray diffraction (shifting the reflex(001) originated from the montmorillonite phase indicating an increase of interlayer distances) as well as by the infrared spectroscopy (occurring of vibrations characteristic for the introduced organic macromolecules). The performed modification causes an increase of the ion exchange ability which allows to assume that the developed hybrid composite: MMT-/maleic acid-acrylic acid copolymer (MMT-co- MA/AA) can find the application as a binding material in the moulding sands technology. In addition, modified montmorillonites indicate an increased ability for ion exchanges at higher temperatures (TG-DTG, UV-Vis). MMT modified by sodium salt of maleic acid-acrylic acid copolymer indicates a significant shifting of the loss of the ion exchange ability in the direction of the higher temperature range (500–700°C).

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Authors and Affiliations

B. Grabowska
S. Cukrowicz
Ż. Kurleto-Kozioł
K. Kaczmarska
D. Drożyński
M. Sitarz
A. Bobrowski

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