Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

Wyszukujesz frazę "wood technology" wg kryterium: Temat


Wyświetlanie 1-5 z 5
Tytuł:
Porównanie wybranych technologii pozyskania drewna pod względem wydajności i kosztów
Comparison of selected wood acquisition technologies as regards output and costs
Autorzy:
Długosiewicz, L.
Grzebieniowski, W.
Powiązania:
https://bibliotekanauki.pl/articles/287056.pdf
Data publikacji:
2009
Wydawca:
Polskie Towarzystwo Inżynierii Rolniczej
Tematy:
drewno
pozyskanie
technologia
wydajność
koszty
wood
technology
acquisition
output
costs
Opis:
W pracy porównano wybrane technologie pozyskania drewna na przykładzie zespołu maszyn wielooperacyjnych typu harwester i forwarder z klembankiem oraz alternatywnej technologii dla pozyskiwania drewna dłużycowego na poziomie ręczno-maszynowym i zrywki z użyciem ciągnika rolniczego przystosowanego do zrywki drewna. Stwierdzono m.in. , że koszty pozyskania drewna przy pomocy harwestera są o około 81% wyższe aniżeli pilarką, a koszty zrywki drewna przy pomocy forwardera są niższe o około 16% niż koszt zrywki ciągnikiem rolniczym.
The paper compares selected technologies used to acquire timber on the example of a set of multi-operational harvester and forwarder type machines with a skidder, and alternative technology used to acquire log wood at manual-mechanical level and skidding with a farm tractor adapted for tree skidding. Among other things, it has been observed that costs of timber acquisition using a harvester are approximately 81% higher compared to sawing machine, and costs of tree skidding using a forwarder are circa 16% lower than cost of skidding with a farm tractor.
Źródło:
Inżynieria Rolnicza; 2009, R. 13, nr 8, 8; 7-13
1429-7264
Pojawia się w:
Inżynieria Rolnicza
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study of Physical and Mechanical Properties of Post-Consumer Wood of Different Age
Autorzy:
Gayda, Serhiy
Kiyko, Orest
Powiązania:
https://bibliotekanauki.pl/articles/27323548.pdf
Data publikacji:
2023
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Technologii Drewna
Tematy:
post-consumer wood
physical properties
mechanical properties
characteristics
strength
recycling
technology
use
Opis:
It should be noted that there is currently a problem with wood resources in the woodworking industry. A potential, unused wood reserve is post-consumer wood (PCW). The problem with the quality of this wood resource has not been fully resolved since there is no regulatory database. In fact, there is a lack of appropriate regulatory documents, which makes it impossible to describe to a full extent the physical and mechanical properties of PCW of common wood species of different ages as a source of additional raw materials for various woodworking technologies. Proceeding from the goal, the task of the study is to describe the physical and mechanical properties of postconsumer wood using the example of fir wood, which for a long period of time has been used to create furniture and joinery products. The task is also to identify patterns of change in the indicators of this resource with age – an expired service life or suitability. In order to use PCW in woodworking and to fill the scientific base with physical and mechanical indicators of fir wood of different ages with an expired product service life, the following characteristics were investigated: static hardness, swelling, coefficients of swelling, the value of transverse anisotropy, density, static bending strength, splitting strength along the fibers, modulus of elasticity in compression, and the modulus of elasticity in static bending. The characteristics of PCW of the widespread fir species in the range of use from 0 to 20 years were explored, with intermediate control over the properties every 5 years. The dynamics of the physical and mechanical indicators of fir PCW were revealed and it was found that in the course of operation time in various conditions they change, mainly decreasingly: static hardness by 9.2-9.6%; the value of transverse anisotropy by 30-32%; strength: static bending strength by 3.4-7.95%, splitting strength by 4.49-8.67%; modulus of elasticity: in compression by 3.89-4.08%, in bending by 2.75-6.64%. The main causes of changes in the properties of PCW with age: natural: weathering, partial internal rot, insect damage, other biological effects; mechanical: splitting, scratches, small holes from means of fastening and other defects due to use; operational: the influence of power and dynamic loads, the influence of surface finishing agents and other factors on the structural elements of wood products. A summary table was compiled for the selection of indicators of the physical and mechanical properties of fir PCW of different ages. When knowing the indicators and dynamics of the physical and mechanical properties of PCW with age, it can be recommended for manufacturing structural materials – blockboards and furniture panels.
Źródło:
Drewno. Prace Naukowe. Doniesienia. Komunikaty; 2023, 66, 212; Art. no. 177453
1644-3985
Pojawia się w:
Drewno. Prace Naukowe. Doniesienia. Komunikaty
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The investigation of properties of blockboards made of post-consumer wood
Autorzy:
Gayda, Serhiy
Kiyko, Orest
Powiązania:
https://bibliotekanauki.pl/articles/2010870.pdf
Data publikacji:
2020
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Technologii Drewna
Tematy:
post-consumer wood
blockboards
mathematical model
physical properties
mechanical properties
characteristics
strength
recycling
technology
use
Opis:
Today in woodworking, there are problems with the use of wood waste and the accumulation of involved wood as an additional and not fully used resource. The problem has not been completely solved, as there is no scientific basis and practical recommendations for efficient production processes with predicting the properties of products made from Post-Consumer Wood (PCW), in particular in the production of blockboards (BB). The objective of the studies is to substantiate and develop a scientific and technical basis for resource-saving and environmentally friendly technologies, to establish the influence patterns of PCW properties on the mechanical characteristics of the products obtained, to develop operating parameters and to formulate practical recommendations, confirmed by the results of experimental studies. The studies have proved the expediency of using PCW in technological processes of woodworking, in particular in the production of construction materials - blockboards with predicted characteristics. In order to rationally use raw materials for the manufacture of conventional blockboards made from Post-Consumer Wood (PCW-BB), new designs of a conventional PCW blockboard with a thickness of 22 mm and with a unified strip width of 16, 32, 48, and 64 mm, the strips are glued ones, 3 mm thick, and faced with plywood on both sides. The authors of the article found that in order to ensure improved operating characteristics of the blockboards, it is important to lay radial, semi-radial and tangential strips in structures with the ratio of width to thickness of the cross-sections of the strips - rationally and efficiently - 1:1, 2:1, 3:1. Substantiation on this basis of new designs of PCW blockboards makes it possible to reveal shortcomings of these products at the conceptual stage of the project and correct them before manufacturing taking into account the specified technical conditions and reducing costs at the development stage. Mathematical models for predicting the main characteristics of conventional PCW blockboards (PCW-BB) have been constructed, which made it possible to determine the indexes of the bending strength of the BB across the strips, σBB, and the shear strength of the BB along the glue line, τВВ. The coefficients of approximation of mathematical dependencies for predicting the strength of PCW-BBs, the strips of which were made of fir wood, were calculated, which would allow for the selection of rational designs of blockboards with appropriate characteristics. It has been established that the developed mathematical models make it possible to predict the characteristics of the PCW-BB depending on the cross-sectional dimensions of the strips, the angle of the annual rings slope to the blockboard face and the age of the PCW, and, on this basis, to propose improved designs of these blockboards for the technological processes of woodworking. The influence patterns of the properties of structural elements on the indicators of conventional PCW-BB (500 × 500 × 22 mm) were experimentally established. It was found that an increase in the width of the strips leads to a decrease in the strength indexes (by 29-37%); an increase in the angle of the annual rings slope to the BB face leads to an increase in static bending strength (by 31-33%) but to a decrease in shear strength (by 4-7%); an increase in the age of the PCW leads to a decrease in strength indexes (by 3-8%). It was found that the physical and mechanical parameters of the experimental PCW-BBs with a strip cross-sections of 1:1, 2:1, 3:1 meet the requirements of the standard (larger values: for static bending of a rate of 15 MPa and for shearing at a rate of 1 MPa), and for the 4:1 cross- -section, they partially had lower indexes by 2-3%. To ensure the strength of the developed structures of the PCW-BBs, it is recommended to use the 3:1 ratio of the sides in the cross-section of the strips, and the slope of the annual rings to the blockboard face must be at least 45o. It was found that the deviation of the values obtained by mathematical models in determining the strength in static bending and shearing in comparison with the experimental ones did not exceed 8% and 10%, respectively.
Źródło:
Drewno. Prace Naukowe. Doniesienia. Komunikaty; 2020, 63, 206; 77-102
1644-3985
Pojawia się w:
Drewno. Prace Naukowe. Doniesienia. Komunikaty
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Rola i dokonania Polskiej Akademii Nauk w rozwoju nauk leśnych
Autorzy:
Grzywacz, A.
Powiązania:
https://bibliotekanauki.pl/articles/1022160.pdf
Data publikacji:
2005
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
Wydzial Nauk Rolniczych,Lesnych i Weterynaryjnych
Komitet Technologii Drewna
instytucje naukowe
Zaklad Badan Lesnych
Komitet Nauk Lesnych
historia
dzialalnosc
Polska
Polska Akademia Nauk
lesnictwo
polish academy of sciences
forest sciences
committee of forest sciences
committee of wood
technology
Opis:
The role, objectives and achievements of the Polish Academy of Sciences in the development of forest services over the past semi−century has been presented. The activity of the Committee on Forest Sciences, the Committee of Wood Technology, as well as of forest and associated scientific institutions has been outlined. The polish and foreign members of the Academy have been listed and its extensive publishing, organisational and popularising activity has been depicted.
Źródło:
Sylwan; 2005, 149, 03; 56-66
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
METROPOL PARASOL W SEWILLI
Metropol Parasol in Seville
Autorzy:
Haduch, Bartosz
Marjański, Łukasz
Powiązania:
https://bibliotekanauki.pl/articles/439773.pdf
Data publikacji:
2017
Wydawca:
Akademia Finansów i Biznesu Vistula
Tematy:
architektura
urbanistyka
przestrzeń publiczna
plac miejski
punkt widokowy
punkt orientacyjny
kontekst historyczny
archeologia
technologia
projektowanie komputerowe
parametryka
drewno
beton
szkło
ornament
efekt Bilbao
architektura hiszpańska
architecture
urbanism
public space
public square
view point
landmark
historical context
archaeology
technology
digital design
parametrics
wood
concrete
glass
Bilbao effect
Spanish architecture.
Opis:
Celem artykułu jest ukazanie historii i szerszego kontekstu wyjątkowej realizacji architektonicznej – wielofunkcyjnego kompleksu Metropol Parasol (architekt: Jürgen Mayer H.) w hiszpańskiej Sewilli oraz jej wpływu na bliższe i dalsze otoczenie. Prezentowane założenie, umiejętnie łączące funkcje miastotwórcze z wysokiej jakości przestrzenią publiczną, stanowi ciekawą ilustrację nowych trendów w projektowaniu architektonicznym na początku XXI wieku (z uwzględnieniem architektury parametrycznej). Realizacja ta jest analizowana w kontekście lokalnym i globalnym, z nakreśleniem tła historycznego. Prezentowany materiał i wyniki badań mogą być punktem wyjścia dla dalszych opracowań dotyczących projektowania w historycznej tkance urbanistycznej.
The main goal of the article is a presentation of the history and broader context of a unique architectural realisation – the multifunctional complex of Metropol Parasol in Spanish Seville (architect: Jürgen Mayer H.) and its impact on the surrounding space. The presented case skilfully connects cityforming functions with high-quality public space, and it may be treated as a fine example of new architectural trends at the beginning of the 21st century (including parametric design). The realisation is analysed in a local, global, and historical context. The material can be a point of departure for further studies concerning architectural design in historical urban fabric.
Źródło:
Kwartalnik Naukowy Uczelni Vistula; 2017, 4(54); 105-113
2084-4689
Pojawia się w:
Kwartalnik Naukowy Uczelni Vistula
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-5 z 5

    Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies