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Open access

Janusz T. Cieśliński, Artur Fiuk, Krzysztof Typiński and Bartłomiej Siemieńczuk

Abstract

This study is focused on experimental investigation of selected type of brazed plate heat exchanger (PHEx). The Wilson plot approach was applied in order to estimate heat transfer coefficients for the PHEx passages. The main aim of the paper was to experimentally check ability of several correlations published in the literature to predict heat transfer coefficients by comparison experimentally obtained data with appropriate predictions. The results obtained revealed that Hausen and Dittus-Boelter correlations underestimated heat transfer coefficient for the tested PHEx by an order of magnitude. The Aspen Plate code overestimated heat transfer coefficient by about 50%, while Muley-Manglik correlation overestimated it from 1% to 25%, dependent on the value of Reynolds number and hot or cold liquid side.

Open access

Sylwia Ciaglo-Androsiuk

Abstract

Relation between morphological traits of the root system and yield related traits is an important issue concerning efforts aiming at improving of ideotype of cultivated plants species, including pea. In this paper, to analyse the dependency between traits describing the root system morphology and yield potential, Person’s and Spearman's_correlations as well as canonical correlations were used.

Root system was analyzed in 14 and 21 day-old seedlings growing in blotting-paper cylinders. Yield potential of pea was analysed in a field experiment. Results of Person’s and Spearman's_correlations revealed that number of lateral roots and lateral roots density were correlated witch yield related traits. Correlation between root length and shoot length was observed only for 14 day-old seedlings. The result of canonical correlations revealed that number of lateral roots and lateral roots density had the largest effect on yield related traits. This work highlights, that in order to improve the yield of pea it might become necessary to understand genetic determination of morphological traits of the root system, especially number of lateral roots.

Open access

Ovidiu Păniţă

Abstract

In the years 2012-2014 on Banu-Maracine DRS were tested an assortment consists of 25 isogenic lines of common wheat (Triticum aestivum ssp.vulgare), with the combination of Rht1&rht8 genes, the analyzed characters being the hight of the strain (cm), the number of seeds/spike, seeds weight/spike (g), no. of spikes/m2, weight of a thousand seeds (WTS) (g) and no. of emerged plants/m2. Based on recorded data and statistical processing of those, they were identified a numbers of links between these characters, links quantified by using the correlation.

Regarding the classification based on the average high of the strain, it was found that that there is a strong link between some characters too. Based on component analysis, the no. of seeds/spike and the seeds weight/spikes are components that influence in excess of 83% variance analysis, a total of five genotypes having positive scores for both factors.

Open access

Sebastian Mucha, Ewa Gornowicz, Mirosław Lisowski, Bartosz Grajewski, Jolanta Radziszewska and Tomasz Szwaczkowski

Abstract

The aim of this study was to estimate coefficients of heritability as well as genetic and phenotypic correlations among body weight and carcass traits. The dataset contained records of 387 birds from the second crossbred generation. The following traits were recorded: body weight (BW) at 11 weeks, carcass weight (CW), breast muscle weight including superficial and deep muscle (BMW), leg muscle weight including thigh and shank (LMW), wings weight (WW), skin with subcutaneous fat weight (SW), abdominal fat weight (AFW), skeleton with the back muscle and inedible elements (SBM), and liver weight (LW). Estimates of variance components were obtained by the average information - REML algorithm in the ASReml package. Very high slaughter yield (74.90%) was obtained. Generally, the coefficients of heritability were high. The highest one of 0.75 was estimated for body weight at 11 weeks. High coefficients of h2 were estimated for breast muscle weight (0.69), wings weight (0.70), carcass weight (0.65), skin with subcutaneous fat weight (0.57) and skeleton with the back muscle (0.58), whereas h2 of liver weight was 0.29. Both phenotypic and genetic relationships between the recorded traits were usually positive. Generally, it seems that the crossbreeding scheme can be perceived as a suitable proposal for the breeding practice.

Open access

Maciej Haman

Internally-driven change and feature correspondence in object representation: A key to children's essentialism?

Two experiments were run to investigate how preschoolers use the pattern of an object's change as a cue to noticing correlations among the object's subsequent features. Four-year-old children were familiarized with either an internally or externally-driven transformation of an object, and tested for identification of an animation that did not match the familiar sequence of the object's features. In both experiments children in the internal-change group identified the incorrect sequence significantly more quickly than in the external-change condition. These results strongly suggest that perception of internally-driven transformation facilitates the formation of and/or access to a representation of correspondences between subsequent features of an object. The possible role of this mechanism in essentialist thinking is discussed at the end of the paper.

Open access

L. A. Apiolaza, C. A. Raymond and B. J. Yeo

Abstract

This study considered the degree of genetic variation for diameter (DBH), basic density (BD), predicted pulp yield (PPY), fibre length (FL), microfibril angle (MFA) and cellulose content (CC) amongst eight subraces of Eucalyptus globulus growing in a field trial in NW Tasmania. There were significant subrace effects for BD, FL and CC. This variation affected the relative profitability of the subraces for pulp production. On average, the most profitable subraces (on NPV/ha over the base population mean) were Strzelecki Ranges ($862.04), Western Otways ($657.80) and Strzelecki Foothills ($576.81). The genetic control (heritability) of variation in DBH, FL and MFA was moderate (0.15 < h2< 0.27), while control for BD, PPY and CC was high (h2> 0.40). Genetic correlations between growth and wood properties were not statistically significant, except for DBHMFA (-0.86). Most genetic correlations amongst wood properties were outside the parametric space (< -1 or >1), but there were significant correlations between BDMFA (-0.70) and PPY-CC (0.82). The empirical response to selection on an index based on a pulp wood objective (which included volume and basic density) resulted in a gain of 4.3% for DBH, 7.9% for BD and marginal changes for all other traits, with a net impact in profit of $1,270/ha. However, future profit calculations will need to consider the effect of FL, MFA and CC on the economics of wood processing to fully evaluate the economic impact of breeding.

Open access

Oana Bogdan, Dorel Mateş, Aura Emanuela Domil, Marina Adriana Puşcaş, Ancuţa Puşcaş and Ramona Teşu

Abstract

Through this paper, we want to identify the correlations between the benefits and costs of adopting IFRS standards in construction entities in the Western Region of Romania and their performance, using the Pearson correlation coefficient, which measures and describes the direction, degree and form of the association between two variables, thus obtaining high, reasonable, weak and very weak links between the benefits / costs and the performance of the entity.

The tool used in the research undertaken by construction companies is the questionnaire.

The questionnaire “On the Costs and Benefits of IFRS in Construction Companies in the Western Region of Romania” was disseminated among professional accountants in order to identify the perceptions of economists operating in construction companies in the Western Region Romania on the costs and benefits of implementing international standards. Thus, through this paper we aim to identify the correlations between the following benefits and costs:

  • - Benefits of implementation: comparability of information, increased transparency, increased access to capital, cost savings, reduction of informational asymmetry,

  • - Implementation costs: IFRS readiness level, complexity of standards, link between accounting and taxation, existing accounting tradition, costs associated with IFRS conversion, and

  • - Performance of the entity viewed from the perspective of: total revenue and turnover. In the research, we chose to present the analysis of compared to both the total revenues and the turnover, because the difference between the two economic-fiscal indicators is mainly represented by the financial revenues and the incomes from the disposals of assets.

Open access

Mahmood Farzaneh-Gord and Hamid Rahbari

Developing novel correlations for calculating natural gas thermodynamic properties

Natural gas is a mixture of 21 components and it is widely used in industries and homes. Knowledge of its thermodynamic properties is essential for designing appropriate processes and equipment. This paper presents simple but precise correlations of how to compute important thermodynamic properties of natural gas. As measuring natural gas composition is costly and may not be effective for real time process, the correlations are developed based on measurable real time properties. The real time properties are temperature, pressure and specific gravity of the natural gas. Calculations with these correlations are compared with measured values. The validations show that the average absolute percent deviation (AAPD) for compressibility factor calculations is 0.674%, for density is 2.55%, for Joule-Thomson coefficient is 4.16%. Furthermore, in this work, new correlations are presented for computing thermal properties of natural gas such as enthalpy, internal energy and entropy. Due to the lack of experimental data for these properties, the validation is done for pure methane. The validation shows that AAPD is 1.31%, 1.56% and 0.4% for enthalpy, internal energy and entropy respectively. The comparisons show that the correlations could predict natural gas properties with an error that is acceptable for most engineering applications.

Open access

Joanna Olbryś and Elżbieta Majewska

Abstract

The main goal of this paper is to explicitly test a research hypothesis that there was no integration effect among the U.S. and the eight Central and Eastern European (CEE) stock markets during the 2007-2009 Global Financial Crisis (GFC). As growing international integration could lead to a progressive increase in cross-market correlations, the evaluation of integration was carried out by applying equality tests of correlation matrices computed over non-overlapping subsamples: the pre-crisis and crisis periods, in the group of investigated markets. The crisis periods are formally established based on a statistical method of dividing market states into bullish and bearish markets. The sample period May 2004-April 2014 includes the 2007 U.S. subprime financial crisis. The robustness analysis of the integration tests with respect to various data frequencies is provided. The empirical results are not homogeneous and they depend both on the integration test and data frequency. Consequently, it is not possible to conclude whether integration between the investigated markets is present.

Open access

Elżbieta Jędrszczyk, Barbara Skowera, Maria Gawęda and Andrzej Libik

Abstract

Cultivation of field tomato in Poland meets unfavorable temperature and precipitation conditions, which affect yield and quality. The aim of the study is to evaluate the effect of temperature and precipitation conditions on the growth and development dynamics of five cultivars of processing tomato. The analysis took into account the key morphological characteristics of the plant, the inflorescence and fruit, which determine the suitability of the cultivar for processing. Analysis of the effect of meteorological elements on the stem development showed that stem length was most strongly influenced by precipitation – both total precipitation and frequency, rather than by temperature; the greater the rainfall, the more intensive stem elongation. High levels of precipitation limited gains in stem thickness. The number of flowers and fruits formed per inflorescence was negatively correlated with temperature. Excessive precipitation during the entire growing period led to formation of smaller fruits. The length and width of the fruit were negatively correlated with the frequency of precipitation in all stages, and with total precipitation during the period from planting to setting of the first fruits. A beneficial effect of temperature on the length and width of the fruit was noted during the entire growing period. The tomato fruit formed a thicker pericarp when precipitation was more frequent.