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Number of results: 9
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Abstract

The probability density functions were used to forecast the air quality in several monitoring sites located in Worek Żytawski region. Prediction of percentile 99.8 value (the maximum allowable 30-minute pollutant concentration) was made on the basis of the frequency function, which represented the annual distribution of SO2. Analysing the historical SO2 concentration data sets identified the form of distribution. The parameters of the distribution were estimated basing upon the annual average concentration prognosis. Then, the preliminary predicted distribution of S02 was verified every month by taking into account successively upcoming concentrations values recorded during the analysed period. The results proved that the air quality estimation obtained with the presented method of verification at the end of September and the ones typically calculated at the end of the year were similarly accurate.
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Authors and Affiliations

Jerzy Zwoździak
Wiwiana Szalińska
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Abstract

The conducted work shows and confirms how thermal analysis of grey and ductile iron is an important source for calculating metallurgical data to be used as input to increase the precision in simulation of cooling and solidification of cast iron. The aim with the methodology is to achieve a higher quality in the prediction of macro– and micro porosity in castings. As comparison objects standard type of sampling cups for thermal analysis (solidification module M ≈ 0.6 cm) is used. The results from thermal analysis elaborated with the ATAS MetStar system are evaluated parallel with the material quality (including tendency to external and internal defects) of the tested specimen. Significant temperatures and calculated quality parameters are evaluated in the ATAS MetStar system and used as input to calibrate the density curve as temperature function in NovaFlow&Solid simulation system. The modified data are imported to the NovaFlow&Solid simulation system and compared with real results.

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Authors and Affiliations

P-E. Persson
Z. Ignaszak
H. Fransson
V. Kropotkin
R. Andersson
A. Kump
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Abstract

The considerations presented in this paper include a computer analysis of slide bearing wear prognosis using the solutions of recurrence equations complemented with the experimental data values. On the ground of the results obtained from analytical and computational numerical calculations, and taking into account the experimental parameters of bearing material and operation boundary conditions, the control problems of slide bearing wear surfaces have been presented. The obtained results allow us to see a connection between roughness, material properties, the amplitude of vibrations, the kind of the friction forces, the hardness of materials, the sliding speed in one side and the wear increments in succeeding time units of the exploitation process in other side.

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Authors and Affiliations

Andrzej Miszczak
Krzysztof Wierzcholski
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Abstract

Four and a half years of African Swine Fever (ASF) in population of free-ranging wild boars and domestic pigs revealed a number of novel insights into the disease epidemiology. Until November 20th, 2018, in total 3048 cases in wild boars and 213 outbreaks in domestic pigs have been confirmed. In spite of low contagiosity as well as low rate of ASF spread in wild boars the disease has an enormous socio-economical impact on the production of pigs in Poland. One of the most important aspects which directly influences the dynamics of ASF spread is the unpredictable hu- man activity. Another important factor responsible for continuous ASF spread is fast recovery of wild boar population in spite of efforts taken by hunters. Assuming our scientific opinion ASF seems to be present in wildlife for the incoming few or several years. Therefore, extraordinary measures should be prepared and undertaken to limit the risk of the occurrence of future out- breaks in domestic pigs. One of the most crucial issues is implementation of strict biosecurity measures in all domestic pigs holdings.

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Authors and Affiliations

Z. Pejsak
K. Niemczuk
M. Frant
M. Pomorska-Mól
A. Ziętek-Barszcz
Ł. Bocian
M. Łyjak
D. Borowska
G. Woźniakowski
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Abstract

The article presents the results of research on the formation of the WF coefficient in coal excavations. The WF coefficient determines the share of the wet surface of the excavation sidewall. The wet part of the excavation sidewall is covered partly by the water film, which evaporates, lowering the temperature of this surface. This coefficient is one of the principal parameters used in forecasting the changes in temperature and humidity of the mine air occurring on the way of contact between the excavation sidewall and the flowing air. During the determination of the coefficient value, the criterion of equality of the actual and forecasted ratios of sensible heat to total heat was assumed in the research methodology. Values of the WF coefficient in the examined excavations generally vary within the range of 0,1-0,6, and they are mostly dependent on the parameters related to the period of ventilation.
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Authors and Affiliations

Marcin Smołka
1
ORCID: ORCID

  1. Central Mining Institute, Plac Gwarków 1, 40-166 Katowice, Poland
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Abstract

An overview of the bibliography regarding the connection of knowledge about precious metal alloys and aspects of the use of computer aided technologies to the optimization of the jewelry casting processes is presented. An analysis of the usability of selected CAx systems was made: 1) for spatial design, called Rhinoceros 6 and 2) CAE system: NovaFlow & Solid (NF&S). The authors describe own research including data acquisition and evaluation of temperature variations during solidification of the selected Au-Ag-Cu alloy, with the identification of the phase transformations of this alloy. The intensity of heat exchange was changed (cooling of specimens under ambient temperature conditions – "normal" intensity and with the furnace – very slow cooling). The problem of completing the simulation database was pointed out and analyzed. Examples of simulations of casting selected jewelry (ring and signet) were given and compared with the result of the experiment realized in real conditions. It was confirmed that the optimization by combining experimental and simulation studies allows for the acquisition of new knowledge, and also facilitates the creation of new artistic designs of jewelry as well as performing the feasibility check, and then optimizing the chosen technology.

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Authors and Affiliations

Z. Ignaszak
J. Wojciechowski
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Abstract

Clinical records of dogs with spontaneous degenerative mitral valve disease (DMVD) with clinical signs related to congestive heart failure (CHF) recruited during routine clinical practice between 2001 and 2018 at the Cardiology Unit of the Veterinary Teaching Hospital (University of Milan) were included in this retrospective cohort study. Baseline echocardiographic data were evaluated. Median survival time (MST) was calculated. Data on therapeutic treatment, ISACHC (International Small Animal Cardiac Health Council) or ACVIM (American College of Veterinary Internal Medicine) classes were reviewed based on the inclusion period and type of endpoint (i.e. cardiac death or death for other causes). A univocal classification was needed, and the patients classified in ISACHC classes II, IIIa and IIIb, visited before 2009, were reallocated to ACVIM class C. The main goal of this data review was to retrospectively evaluate 259 clinical records of subjects belonging to ACVIM C class examined between 2001 to 2018 and 202 dogs examined between 2010 to 2018. In this way, in the second group, the bias of the reclassification was avoided. The MST (median survival time) of these subjects was 531 d (2001-2018) and 335.5 d (2010-2018), respectively. Univariate survival regression analysis for subjects included from 2010 to 2018 showed as significantly related to cardiac death (CD): left atrium to aorta ratio (LA/Ao) (HR 2.754, p=0.000), E wave (HR 2.961, p=0.000), E/A ratio (HR 1.372, p=0.000), end-diastolic (HR 1.007, p=0.000) (EDVI) and end-systolic (HR 1.012, p=0.026) (ESVI) volume indexes, allometric diastolic (HR 4.018, p=0.000) (LVIDdN) and systolic (HR 2.674, p=0.049) (LVIDsN) left ventricular internal diameters, age (HR 1.006, p=0.009) and pulmonary hypertension severity (HR=1.309, p=0.012) (PH). Multivariate analysis, adjusted for age, showed that the only variable that determined a statistically significant difference in MST was PH severity (HR 1.334, p=0.033). The type of therapeutic treatment within this class was not significant for the MST of the subjects.
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Authors and Affiliations

M. Bagardi
1
C. Locatelli
1
A. Zanaboni
2
A. Galizzi
1
D. Malchiodi
2
P.G. Brambilla
1

  1. University of Milan, University Veterinary Teaching Hospital, Via dell’Università n. 6, 26900 Lodi (LO), Italy
  2. University of Milan, Informatic Department, Via Giovanni Celoria n. 18, 20133 Milan (MI), Italy
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Abstract

The article deals with the problems of prevention in the preservation and development of idioms in the multilingual territory between the Dniester and the Danube rivers, based on the sociolinguistic situation of the region, the language and educational policy in the area and their dynamics, and a search for a solution. The goal involves modeling forecasts (possible development vectors) of the ethnolinguistic situation within the investigated area, in order to be able to avoid negative scenarios, but to move along the path of its harmonious development, to find tools and measures for its constructive management. It is considered that the problems preventing the preservation of this continuum’s linguistic diversity, as well as the development of idioms in a multilingual environment, are caused by both internal (problems of effective implementation of the language and educational policy of Ukraine) and external factors. In order to ensure the preservation and development of the area’s idioms, some negative, unfavorable scenarios in the development of the ethnolinguistic and political situation were modeled. In our opinion, a number of measures should be taken to prevent the ethno‑linguistic situation from developing along such destructive vectors. First of all, it is necessary to form, in some ways reanimate, a positive image of the Ukrainian Language, at least – it should not be perceived by minorities as an imposed language. If the Ukrainian authorities do not have an understanding of this necessity, the European Union could influence the resolution of many partial issues with the linguistic life of the region.
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Authors and Affiliations

Andrii Kolesnykov
1
ORCID: ORCID
Maryna Deliusto
1
ORCID: ORCID

  1. Izmail State University of Humanities
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Abstract

The paper presents the meaning of complexity as a notion in psychology, and its influence on architectural theory in the 1960s, focusing on the notion of optimal complexity. A commentary is presented on the two texts („Network of straight lines” and „Limited complexity”) by professor architect Juliusz Żórawski from 1967, where he has introduced the term of limited complexity in relation to architecture, and where he criticizes excessively far reaching forecasts of future development. Żórawski’s concepts are parallel to those of R. Venturi at that time.

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Authors and Affiliations

J. Krzysztof Lenartowicz

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