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Wyświetlanie 1-9 z 9
Tytuł:
Variability in and correlations among selected physical properties of European larch (Larix decidua Mill.) seeds
Autorzy:
Kaliniewicz, Z.
Tylek, P.
Anders, A.
Markowski, P.
Rawa, T.
Powiązania:
https://bibliotekanauki.pl/articles/297835.pdf
Data publikacji:
2014
Wydawca:
Uniwersytet Warmińsko-Mazurski w Olsztynie
Tematy:
seeds
physical properties
coefficients
correlation
Opis:
Selected physical attributes of European larch seeds harvested from 2 seed plantations and 2 commercial seed stands in north-eastern Poland were determined. The physical properties of seeds were measured, and the results were used to calculate indicators of seed weight and the frictional and geometric properties of seeds. Physical attributes and indicators were compared by Student’s t-test for independent samples, analysis of variance, correlation analysis and linear regression analysis. The average values of physical properties and indicators were determined at: critical transport velocity - from 5.93 to 6.13 m • s-1, thickness - from 1.25 to 1.43 mm, width - from 2.29 to 2.71 mm, length - from 3.71 to 4.57 mm, angle of sliding friction - from 27.85 to 31.98o, weight - from 4.03 to 6.14 mg, coefficient of sliding friction - from 0.54 to 0.63, arithmetic mean diameter - from 2.42 to 2.90 mm, geometric mean diameter - from 2.20 to 2.60 mm, aspect ratio - from 59.60 to 62.38%, sphericity index - from 57.27 to 59.40%, specific weight - from 1.81 to 2.33 g • m-1, volume - from 4.60 to 7.59 mm3 and density - from 0.82 to 0.91 g • cm-3. The material harvested in seed plantations differed from seeds from commercial seed stands in all parameters, excluding critical transport velocity. Seed weight was most correlated with the remaining parameters. The highest value of the correlation coefficient and the equation with the highest value of the coefficient of determination were reported for the dependence between seed weight and seed length. Seed weight was also relatively highly correlated with seed width, therefore, the use of mesh screens with round openings and/or cylindrical grain graders is recommended in seed sorting processes.
Źródło:
Technical Sciences / University of Warmia and Mazury in Olsztyn; 2014, 17(2); 123-134
1505-4675
2083-4527
Pojawia się w:
Technical Sciences / University of Warmia and Mazury in Olsztyn
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of saw chain type and wood species on the kickback angle of a chainsaw
Autorzy:
Kaliniewicz, Z.
Maleszewski, Ł.
Krzysiak, Z.
Powiązania:
https://bibliotekanauki.pl/articles/297817.pdf
Data publikacji:
2018
Wydawca:
Uniwersytet Warmińsko-Mazurski w Olsztynie
Tematy:
chainsaw
kickback
saw chain
wood
correlation
Opis:
Wood processing operations, in particular debarking, can pose a significant hazard for the chainsaw operator when performed without due caution. The most common hazards with potentially fatal consequences include kickback which occurs when the chainsaw’s guide bar is violently thrown backwards towards the operator. The aim of this study was to determine the influence of wood species and different saw chain brands on the kickback angle of a chainsaw. The kickback angle of a combustion chainsaw was analyzed in a self-designed test stand with the use of a digital level gauge accurate to 0.1°. Four differently priced saw chain brands, including two standard chains and two chains with anti-kickback features, were evaluated. Kickback was analyzed on five wood species (pine, spruce, birch, alder and oak) at three engine speeds (50%, 75% and 100% of maximum rotational speed). Kickback was significantly determined by wood species and saw chain type, and it was less influenced by the rotational speed of the chainsaw engine. The average kickback angle was largest in alder and smallest in spruce. The analyzed parameter was not always reduced by saw chains with anti-kickback features. In some cases, low-priced saw chains with anti-kickback features offer less protection than more expensive standard chains. Chainsaw buyers should decide whether it is worthwhile to compromise on safety in exchange for a lower price.
Źródło:
Technical Sciences / University of Warmia and Mazury in Olsztyn; 2018, 21(4); 323-334
1505-4675
2083-4527
Pojawia się w:
Technical Sciences / University of Warmia and Mazury in Olsztyn
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Correlations between basic physical parameters of nuts and the weight of common beech (Fagus sylvatica L.) seeds
Autorzy:
Kaliniewicz, Z.
Tylek, P.
Anders, A.
Markowski, P.
Rawa, T.
Andros, K.
Powiązania:
https://bibliotekanauki.pl/articles/297912.pdf
Data publikacji:
2015
Wydawca:
Uniwersytet Warmińsko-Mazurski w Olsztynie
Tematy:
nuts
seeds
physical properties
variation
correlation
Opis:
Selected physical attributes of common beech nuts harvested from four tree stands in northern Poland were determined. Seeds were manually extracted from every nut. Seeds and nuts were weighed, and the results were used to determine the ratio of seed weight to nut weight, which described the degree of nut filling. Physical parameters and the calculated coefficients were compared by the t-test for independent samples, analysis of variance, correlation analysis and linear regression analysis. The following ranges of variation were reported in the physical attributes of nuts and the coefficients of common beech seeds: critical transport velocity of nuts - from 6.33 to 11.28 m s-1, nut thickness - from 4.76 to 9.86 mm, nut width - from 6.46 to 13.54 mm, nut length - from 12.63 to 21.62 mm, angle of sliding friction of nuts - from 15.67 to 26.67o, nut weight - from 93.0 to 513.7 mg, coefficient of sliding friction of nuts - from 0.28 to 0.50, seed weight - from 11.0 to 374.8 mg, and ratio of seed weight to nut weight - from 0.08 to 0.88. The majority of nuts contained one seed (average weight of 195.36 mg), and only 2.3% of nuts contained two seeds (average weight of 103.11 mg). The attribute that was most highly correlated with the ratio of seed weight to nut weight was seed weight (0.685), followed by critical transport velocity (0.527) and weight of nuts (0.493). The results indicate that common beech seeds would be processed most effectively in vibration-pneumatic separators or, alternatively, in pneumatic separators where nut fractions obtained with the use of mesh screens can be sorted separately.
Źródło:
Technical Sciences / University of Warmia and Mazury in Olsztyn; 2015, 18(1); 5-14
1505-4675
2083-4527
Pojawia się w:
Technical Sciences / University of Warmia and Mazury in Olsztyn
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of correlations between selected physical properties and color of scots pine (Pinus sylvestris L.) seeds
Autorzy:
Kaliniewicz, Z.
Tylek, P.
Markowski, P.
Anders, A.
Rawa, T.
Głażewska, E.
Powiązania:
https://bibliotekanauki.pl/articles/298468.pdf
Data publikacji:
2014
Wydawca:
Uniwersytet Warmińsko-Mazurski w Olsztynie
Tematy:
pine
seed
physical attributes
color
correlation
Opis:
Selected physical properties of Scots pine seeds harvested from five plantations in north-eastern Poland were determined. Seed color was determined in a sensory analysis, and seeds were classified into one of four color groups: black, brown, gray or other. The results of measurements were used to calculate indicators of seed weight and seeds’ frictional and geometric properties. Physical attributes and indicators were compared by one-way analysis of variance, correlation analysis and linear regression analysis. The average values of physical properties and indicators characterizing seeds from different color groups were determined at: critical transport velocity - from 7.0 to 7.1 m • s-1, thickness - from 1.48 to 1.50 mm, width - from 2.51 to 2.54 mm, length - from 4.32 to 4.46 mm, angle of sliding friction - from 29.1 to 29.8o, weight - from 6.4 to 6.7 mg, coefficient of sliding friction - from 0.56 to 0.58, arithmetic mean diameter - from 2.77 to 2.82 mm, geometric mean diameter - from 2.52 to 2.55 mm, aspect ratio - from 56.91 to 58.64%, sphericity index - from 57.44 to 58.69%, specific weight - from 2.51 to 2.60 g • m-1, volume - from 7.90 to 8.24 mm3 and density - from 0.80 to 0.82 g • cm-3. Selected color groups differed only in length, aspect ratio and sphericity index. Seed weight was most highly correlated with the remaining attributes, and the highest value of the correlation coefficient and the equation with the highest value of the coefficient of determination were reported for the correlation between seed weight and thickness.
Źródło:
Technical Sciences / University of Warmia and Mazury in Olsztyn; 2014, 17(3); 259-274
1505-4675
2083-4527
Pojawia się w:
Technical Sciences / University of Warmia and Mazury in Olsztyn
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Correlations between germination capacity and selected physical properties of perennial ryegrass cv. Maja seeds
Autorzy:
Kaliniewicz, Z.
Jadwisieńczak, K.
Jadwisieńczak, B.
Potkaj, Ł.
Powiązania:
https://bibliotekanauki.pl/articles/297989.pdf
Data publikacji:
2016
Wydawca:
Uniwersytet Warmińsko-Mazurski w Olsztynie
Tematy:
seeds
physical parameters
germination rate index
correlation
Opis:
Perennial ryegrass is one of the most valuable pasture grasses. The species is recommended for sodding various types of land in Poland due to its fast growth and the ability to produce large numbers of vegetative shoots. Seedling emergence and biomass yield are largely determined by seed quality. This study analyzes the correlations between the basic physical properties of seeds of perennial ryegrass cv. Maja and their germination capacity. The basic dimensions (length, width and thickness) and mass of each of the 150 seeds were determined, and their arithmetic mean diameter, geometric mean diameter, aspect ratio, sphericity index and density were calculated. The seeds were germinated for 14 days, and the results were recorded daily, which enabled to determine germination time for each seed. The relationships between the evaluated parameters were determined by the Student’s t-test for independent samples and correlation analysis. The analyzed physical properties of seeds had no significant effect on the germination rate index. Germinated and non-germinated seeds differed significantly in width, length and arithmetic mean diameter, but they should not be sorted based on their plumpness to improve the quality of seed material because it could lead to a high loss of viable seeds.
Źródło:
Technical Sciences / University of Warmia and Mazury in Olsztyn; 2016, 19(1); 5-16
1505-4675
2083-4527
Pojawia się w:
Technical Sciences / University of Warmia and Mazury in Olsztyn
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Basic physical properties of Norway spruce (Picea abies (L.) Karst.) seeds
Autorzy:
Kaliniewicz, Z.
Markowski, P.
Anders, A.
Jadwisieńczak, B.
Rawa, T.
Szczechowicz, D.
Powiązania:
https://bibliotekanauki.pl/articles/298166.pdf
Data publikacji:
2016
Wydawca:
Uniwersytet Warmińsko-Mazurski w Olsztynie
Tematy:
seed
dimension
seed mass
range of variations
correlation
separation
Opis:
The range of variations in a given separation parameter and its relationships with other attributes have to be determined for designing seed cleaning and sorting processes. In this study, those relationships were determined for five batches of Norway spruce seeds supplied by a seed extraction plant in Jedwabno. The seeds were harvested from seed stands in northern Poland. The terminal velocity, length, width, thickness and mass of every seed were determined. The results were used to calculate the geometric mean diameter, aspect ratio, sphericity index and density of the evaluated seeds. Those parameters were compared by analysis of variance and linear correlation analysis. Similarities in the average values of all physical properties were noted only between seeds harvested in the same seed zone, from tree stands occupying the same habitat type. The analyzed seeds can be effectively separated into mass fractions with the use of traditional sorting devices such as pneumatic separators, mesh sieves with longitudinal or round openings, cylindrical graders, winnowing machines and pneumatic sieves, in order to achieve more uniform seedling emergence when each seed fraction is sown separately.
Źródło:
Technical Sciences / University of Warmia and Mazury in Olsztyn; 2016, 19(2); 103-115
1505-4675
2083-4527
Pojawia się w:
Technical Sciences / University of Warmia and Mazury in Olsztyn
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Selected physical parameters of common hornbeam (Carpinus betulus L.) nuts
Autorzy:
Kaliniewicz, Z.
Tylek, P.
Markowski, P.
Anders, A.
Rawa, T.
Liedtke, M.
Powiązania:
https://bibliotekanauki.pl/articles/298164.pdf
Data publikacji:
2015
Wydawca:
Uniwersytet Warmińsko-Mazurski w Olsztynie
Tematy:
common hornbeam
seeds
physical parameters
range of variations
correlation
separation
Opis:
Selected physical parameters of common hornbeam nuts were determined in five batches of nuts harvested from seed tree stands in northern Poland. The results were used to calculate the arithmetic and geometric mean diameters, aspect ratio, sphericity index, volume and density of each nut. The above parameters were compared by analysis of variance, correlation analysis and linear regression analysis. Habitat conditions had a greater influence on nut plumpness than the age of the tree stand. Nut width was highly correlated with nut mass, and the above observation can be used in the process of separating nuts into mass categories. When two mesh screens with 5 mm and 6 mm openings are used, nuts will be separated into a fine-sized fraction containing 71.4% of nuts with reduced plumpness, 24.1% of moderately plump nuts and 1.8% of plump nuts, and a coarse-sized fraction containing 2.0% of nuts with reduced plumpness, 43.6% of moderately plump nuts and 54.4% of plump nuts.
Źródło:
Technical Sciences / University of Warmia and Mazury in Olsztyn; 2015, 18(4); 247-259
1505-4675
2083-4527
Pojawia się w:
Technical Sciences / University of Warmia and Mazury in Olsztyn
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analiza związków masy i podstawowych wymiarów ziaren gryki i segmentów łuszczyn rzodkwi świrzepy
Analysis of relationships betwen mass and basic dimensions buckwheat and wild radish segments
Autorzy:
Kaliniewicz, Z.
Rawa, T.
Powiązania:
https://bibliotekanauki.pl/articles/288452.pdf
Data publikacji:
2005
Wydawca:
Polskie Towarzystwo Inżynierii Rolniczej
Tematy:
gryka
segmenty łuszczyn
rzodkiew świrzepa
wymiary
masa
współzależność cech
buckwheat
wild radish segments
dimensions
mass correlation of features
Opis:
W pracy przedstawiono metodykę i wyniki pomiarów grubości, szerokości i długości oraz masy ziaren gryki i łuszczyn rzodkwi świrzepy. Określono związek korelacyjny i matematyczny między przyjętymi cechami. Uzyskano równania, które można wykorzystać zarówno do budowy matematycznych modeli ziaren gryki i segmentów łuszczyn rzodkwi świrzepy, jak i matematycznych modeli procesów rozdzielczych.
The methodology and results of measurements of thickness, width and length as well as mass of buckwheat and wild radish seeds in work were introduced. Between received features, the correlation and mathematical relationships were qualified. The obtained equations can be used to building of mathematical models of buckwheat and wild radish segments seeds as well as to the mathematical modelling of cleaning processes.
Źródło:
Inżynieria Rolnicza; 2005, R. 9, nr 6, 6; 287-295
1429-7264
Pojawia się w:
Inżynieria Rolnicza
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wpływ wieku drzewostanu macierzystego na wybrane cechy fizyczne nasion świerka pospolitego
Influence of the age of parent stand on selected physical properties of Norway spruce seeds
Autorzy:
Kaliniewicz, Z.
Markowski, P.
Anders, A.
Tylek, P.
Krzysiak, Z.
Fura, S.
Powiązania:
https://bibliotekanauki.pl/articles/987167.pdf
Data publikacji:
2017
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
lesnictwo
hodowla lasu
drzewostany mateczne
wiek drzewostanu
wiek drzew
swierk pospolity
Picea abies
nasiona
cechy fizyczne
sortowanie
tree age
seeds
properties
variation
correlation
sorting
picea abies
Opis:
The objective of this study was to determine the influence of the age of parent tree stand on selected physical properties of Norway spruce seeds to improve the efficiency of seed separation processes. Seeds were harvested in a forest complex located in the seed zone No. 202, in the municipality of Kruklanki in the Borki Forest District (N Poland) during mast years (1999, 2004, 2007 and 2012). The experimental material comprised of Norway spruce seeds from three differently aged tree stands (86, 119 and 129 years old in the first harvest year). The following measurements were performed for each seed: terminal velocity – with a pneumatic classifier; length and width – with a laboratory microscope; thickness – with a thickness gauge; angle of external friction – on an inclined plane, in two positions on a steel friction plate, and mass – with a laboratory scale. The results were used to calculate the arithmetic and geometric mean diameters, aspect ratio, sphericity index and density of seeds. The values of the analyzed properties were compared with ANOVA for factorial designs and linear correlation analysis. The results of the study indicate that Norway spruce seeds obtained from cones harvested in 2012 are characterized by the highest thickness and, consequently, by the highest values of the aspect ratio and sphericity index. The age of parent trees significantly influences the majority of physical properties of seeds. However, the patterns of observed changes are difficult to interpret due to the impact of weather conditions and the genetic potential of parent trees, which perform differently in response to changing climate and geomorphological conditions. Over the analyzed 13−year period a gradual increase was noted in the width, geometric mean diameter, aspect ratio and sphericity index of seeds, whereas the length and density of seeds decreased. Therefore, Norway spruce seeds should be separated mostly with the use of mesh screens with longitudinal openings, pneumatic separators and graders. The use of those devices, separately or in combination, for sorting Norway spruce seeds into mass fractions could contribute to more uniform seedling emergence when every seed fraction is sown separately.
Źródło:
Sylwan; 2017, 161, 07; 548-557
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-9 z 9

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