Wyniki wyszukiwania - Biblioteka Nauki

1

A statistical assessment of consumers' criteria regarding organic agricultural products: the case of organic olive oil

100%

Baourakis G. , Apostolakis I.

Foundations of Computing and Decision Sciences

|

1999

|

tom Vol. 24, No. 1

21-31

EN

The socio-economic parameters of organic farn1ing in the restructuring of small to medium agricultural economies, such as that of Greece, are of significant importance. In these cases organic farn1ing seems to offer a promising alternative and profitable agricultural practice, particularly where organic olive oil is concerned. The paper aims to find, with a statistical assessment, the criteria that the consumers use in order to choose organic products and their willingness to pay in order to buy them. An overview of the Greek organic farming structure is presented and the subjects of the supply of, and demand for, organic olive oil are discussed. A market survey2 was conducted in several areas of Greece in order to record quantitative data, preferences, purchasing criteria, buying procedures and attitudes towards organic olive oil.

2

Statistical Assessment of Coal Charge Effect on Metallurgical Coke Quality

75%

Pustejovska P. , Brozova S. , Jursova S.

Production Engineering Archives

|

2016

|

tom Vol. 11, No. 2

15--17

EN

The paper studies coke quality. Blast furnace technique has been interested in iron ore charge; meanwhile coke was not studied because in those previous conditions seemed to be good enough. Nowadays, the requirements for blast furnace coke has risen, especially, requirements for coke reactivity [1]. The level of reactivity parameter is determined primarily by the composition and properties of coal mixtures for coking. The paper deals with a statistical analysis of the tightness and characteristics of the relationship between selected properties of coal mixture and coke reactivity. Software Statgraphic using both simple linear regression and multiple linear regressions was used for the calculations. Obtained regression equations provide a statistically significant prediction of the reactivity of coke, or its strength after reduction of CO2, and thus their subsequent management by change in composition and properties of coal mixture [2]. There were deter-mined indexes CSR/CRI for coke [3]. Fifty – four results were acquired in the experimental parts where correlation between index CRI and coal components were studied. For linear regresion the determinant was 55.0204%, between parameters CRI – Inertinit 21.5873%. For regression between CRI and coal components it was 31.03%. For multiply linear regression between CRI and 3 feedstock components determinant was 34.0691%. Final correlation has shown the decrease in final coke reactivity for higher ash, higher content of volatile combustible in coal increases the total coke reactivity and higher amount of inertinit in coal increases the reactivity. Generally, coke quality is significantly affected by coal processing, carbonization and maceral content of coal mixture.

3

Statistical assessment of certain properties of soil under permanent grasslands

63%

Wylupek T. , Gawryluk A.

Journal of Elementology

|

2016

|

tom 21

|

nr 2

EN

Geobotanical studies comprised soil and permanent grasslands in the valley of the Por River. The paper describes an assessment of the content of organic matter, reaction (pH) and availability of P, K and Mg in meadow soils overgrown with plant communities classified within the following syntaxonomic units: associations Phragmition and Magnocaricion, orders Molinietalia and Arrhenatheretalia, classes Scheuchzerio-Caricetea nigrae and the order Trifolio fragiferae-Agrostietalia stoloniferae. The results of chemical analyses were confronted with the limit ordinals after IUNG in Puławy (1990) and submitted to statistical analysis using the system of SAS 9.2 from Enterprise Guide 4.2. The analyzed habitats of permanent grasslands had neutral reaction and were dominated by organic soils. Mineral soils occurred in a small area. Generally, a very high or high availability of assimilable P, a low or very low availability of K and a differentiated content of Mg were found in organic soils. In mineral soils, on the other hand, a very high content of P and Mg and a very low content of K were observed. Comparative analyses of selected properties of the habitats showed very significant diversity. Variability coefficients were generally characterized by high values, which points to considerable differentiation of the analyzed properties of the soils within the distinguished syntaxonomic units. Based on our analysis of the Pearson’s correlation coefficients, a number of relations, both positive and negative ones, can be noticed between the properties studied.

4

Statystyczna ocena zagrożenia porażeniowego podczas zwarć doziemnych w stacjach elektroenergetycznych średnich napięć

63%

Kmak J. , Nowak W. , Tarko R.

Przegląd Elektrotechniczny

|

2022

|

tom R. 98, nr 10

99--102

PL

Artykuł dotyczy oceny zagrożenia porażeniowego podczas zwarć doziemnych w stacjach elektroenergetycznych średnich napięć zasilanych z sieci o nieskutecznie uziemionym punkcie neutralnym. Podstawę tej oceny stanowią wartości napięć uziomowych, które zależą od wartości prądu zwarcia doziemnego oraz od mającej losowy charakter wartości rezystancji uziemienia stacji. W artykule zaproponowano oryginalną metodę statystycznej oceny zagrożenia porażeniowego, którą wykorzystano do analizy rzeczywistej sieci 15 kV.

EN

The article concerns the shock hazard during earth faults in medium-voltage substations supplied from networks with non-effectively earthed neutral point. The basis for the risk assessment are the values of earth voltages which depend on the value of earth fault current and on random value of substation earth resistance. This paper proposes an original method for statistical assessment of the electric shock hazard, which was used to analyze the real 15 kV network.

5

Program iteracyjny obliczenia parametrów sfery oraz ich ocena statystyczna dla WMP

51%

Filipowski R. , Lechniak Z. , Zawora J.

|

2015

|

tom R. 10, nr 5-6

20--23

PL

Sferę w przestrzeni 3D określają cztery parametry, to jest, współrzędne położenia środka sfery oznaczone (mx,my,,mz) oraz jej promień R. Na rys. przedstawiono hipotetyczną sferę oraz chmurę punktów oznaczonych przez Pi, uzyskanych podczas pomiaru sfery sondą pomiarową na WMP. Na podstawie uzyskanego ciągu punktów oblicza się w cyklu iteracyjnym, niżej przedstawionym, cztery parametry hipotetycznej sfery.