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1

Influence of the thin-wall ratio on the limiting spinning ratio and the thinning of the AMS 5504 sheet in spinning

Kut Stanisław, Ryzińska Grażyna, Mrugała Tomasz

Hutnik, Wiadomości Hutnicze

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2023

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Vol. 90 nr 4

15--19

EN

The paper contains the results of experimental research on the AMS 5504 sheet spinning process. The research was carried out on a Leifeld SFC 800 V500 two-roller metal spinning machine with a vertical axis. Various shapes of rollers and different thicknesses of sheet metal were used.The relationships between the limiting spinning ratio, thin-wall ratio and the fillet radius of roller were determined, and the occurrence of negative phenomena during the spinning process, such as wrinkling or cracking, was taken into account. The conclusions contained in the work and the developed methodology allow for a practical assessment of the possibility of producing drawpiece with given parameters by spinning.

PL

W pracy przedstawiono wyniki badań eksperymentalnych procesu wyoblania blachy AMS 5504. Badania przeprowadzono na dwurolkowej wyoblarceLeifeld SFC 800 V500 o osi pionowej. Zastosowano różne kształty rolek i różną grubość blachy. Określono zależności pomiędzy granicznym współczynnikiem wyoblania, współczynnikiem cienkościenności i promieniem zaokrąglenia rolki, a także uwzględniono występowanie negatywnych zjawisk podczas procesu wyoblania, takich jak fałdowanie czy pękanie. Wnioski zawarte w pracy oraz opracowana metodologia pozwalają na praktyczną ocenę możliwości wytwarzania wytłoczki o zadanych parametrach metodą wyoblania.

2

Variation Between Voivodships in Terms of Forest Area and Silviculture Activities in Polish Forests in 2015-2019

Grużewska Agata, Rymuza Katarzyna, Niewęgłowski Marek

Rocznik Ochrona Środowiska

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2021

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Tom 23

524--538

EN

The objective of the study reported here was to compare voivodships in terms of forest area, forest regeneration area, afforested area, thinned forest area and natural forest regeneration area Main Statistical Office data for Polish voivodships was analysed. It included forest area, natural forest regeneration and silviculture activities (forest regeneration, afforestations and thinning) in all forests, state-owned forests and privately-owned forests. Voivodships were compared using the arithmetic mean, the indicator of structure, the average rate of change, principal component analysis and cluster analysis. Principal Component Analysis, revealed that state-owned forest area, forest regeneration in state forests, total forest regeneration, and thinning in state-owned forests had the greatest share in the multivariate variation among voivodships analysed in terms of forestry. Cluster analysis yielded two groups of voivodships. The voivodships in the first group had a higher average total forest area, area of state-owned forests, total area of forest regeneration and forest regeneration in state-owned forests, area of natural forest regeneration and thinning in state-owned forests. On average, forests of voivodships which formed group 2 included less privately-owned forests in which fewer forest regeneration and afforestation activities had been conducted. Opolskie and Śląskie Voivodships as well as Łódzkie and Świętokrzyskie Voivodships were the most similar in terms of all the analysed characteristics.

3

The Locality of Bear’s Garlic (Allium ursinum L.) in Palace Park in Korytów – Environmental Conditions and Protection Possibilities

Szymura M., Liszewski M., Kocowicz A., Pytlarz-Kozicka M., Szymura T. H.

Architektura Krajobrazu

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2015

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nr 4

48--59

EN

The aim of this study is to characterize the habitat preferences of Wild garlic (Allium ursinum), determine the potential environmental threats and possibilities of protection of this species and also, to show the possibility of its use as a natural element in landscape planning. The palace park in Korytów (Kłodzko Valley, Lower Silesia) was selected as a model area for the study. The research has shown that bear garlic is a highly demanding plant in terms of soil conditions. The threat to this species is soil eutrophication related to the influence of anthropogenic factor and excessive cutting of forest trees. In order to protect the wild garlic population it is recommended to reduce the felling of trees and remove competitive species like Impatiens parviflora and Urtica dioica.

PL

Celem pracy jest charakterystyka preferencji siedliskowych czosnku niedźwiedziego (Allium ursinum), określenie potencjalnych zagrożeń i możliwości ochrony tego gatunku oraz pokazanie możliwości jego wykorzystania jako elementu naturalistycznego w kształtowaniu krajobrazu. Jako modelowe stanowisko wybrano park przypałacowy w Korytowie (Kotlina Kłodzka, Dolny Śląsk). Czosnek niedźwiedzi wykazuje duże wymagania w stosunku do warunków glebowych. Zagrożeniem dla tej rośliny są eutrofizacja gleb związana z wpływem czynnika antropogenicznego i nadmierne prześwietlenie drzewostanów. W celu ochrony czosnku niedźwiedziego zaleca się ograniczenie wycinki drzew oraz usuwanie roślin z nim konkurujących takich jak niecierpek drobnokwiatowy (Impatiens parviflora) i pokrzywa zwyczajna (Urtica dioica).

4

Kategorie i ilość uszkodzeń drzew przy pracach pozyskaniowych

Lewaszkiewicz Ł., Grieger A., Żukowska K.

Inżynieria Rolnicza

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2013

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R. 17, nr 3, t. 2

225--234

PL

W artykule przedstawiono wyniki badań skali uszkodzeń drzew przy pracach leśnych z wykorzystaniem specjalistycznych maszyn. Badania zostały przeprowadzone w Nadleśnictwie Rokita, Regionalna Dyrekcja Lasów Państwowych w Szczecinie. Pod uwagę wzięto skutki zastosowania maszyn do ścinki i zrywki drewna. Prace były prowadzone w drzewostanach trzebieżowych. Na podstawie uzyskanych wyników stwierdzono, że największe szkody co do liczby generowane są przez harwestery podczas ścinki drzew. Uszkodzenia dotyczą odsłoniętej bieli drzewa w ilości 57 szt·ha-1. Przy pracach zrywkowych przy użyciu forwardera zanotowano natomiast 4 szt·ha-1 połamanych gałęzi. Ilość uszkodzeń była zdecydowanie większa przy pracach wykonywanych w trzebieży późnej pozytywnej, gdzie nie było szlaków zrywkowych. W trzebieży, gdzie były zastosowane szlaki technologiczne, liczba uszkodzeń zdecydowanie malała. Parametry technologiczne maszyn w 50% nie były dostosowane do parametrów technologicznych drzewostanu.

EN

The article presents the research results of the damage scale of trees at forestry works with the use of specialistic machines. The research was carried out in Rokita Forestry Management, Regional Management of National Forests in Szczecin. The effects of using cutting and logging machines were taken into account. The works were carried out in thinning forest stand. Based on the obtained results it was found out that the biggest damage concerning the number are generated by harvesters during cutting trees. Damage concern the exposed tree alburnum in the amount of 57 item·ha-1. At the logging works with the use of forwarder 4 item·ha-1 of broken branches were reported. Number of damage was decisively higher at the works performed in a late positive thinning, where there were no skidding roads. In thinning, where technological roads were used, the number of damage decisively decreased. Technological parameters of machines were not adjusted to technological parameters of the forest stand in 50%.

5

Extraction of centre line from curvilinear objects

Rokicki J., Matiukas V., Ušinskas A., Adaškevičius R.

Opto-Electronics Review

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2011

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Vol. 19, No. 1

22-29

EN

This tutorial paper surveys three methods designed to detect the centre line in curvilinear structures. These are the iterative thinning, Steger's and derivatives' methods. We aim to illustrate the effectivness of the chosen methods for processing laser-trace images and magnetic resonance slices of human head. The essence of each three methods is presented and important parameters are discussed. Experiments have been carried out and results are discussed in the light of the quality of the centre line produced and work time of all three methods.

6

K3M: A universal algorithm for image skeletonization and a review of thinning techniques

Saeed K., Tabędzki M., Rybnik M., Adamski M.

International Journal of Applied Mathematics and Computer Science

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2010

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Vol. 20, no 2

317-335

EN

This paper aims at three aspects closely related to each other: first, it presents the state of the art in the area of thinning methodologies, by giving descriptions of general ideas of the most significant algorithms with a comparison between them. Secondly, it proposes a new thinning algorithm that presents interesting properties in terms of processing quality and algorithm clarity, enriched with examples. Thirdly, the work considers parallelization issues for intrinsically sequential algorithms of thinning. The main advantage of the suggested algorithm is its universality, which makes it useful and versatile for a variety of applications.

7

3D skeletonization of pulmonary airway tree structures

Postolski M., Janaszewski M., Jopek Ł., Babout L.

Automatyka / Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie

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2010

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T. 14, z. 3/1

337-351

EN

Quantitative analysis of the human airway trees is a challenge in image processing and analysis. Results obtained in previous work on this subject are still not sufficient and they need improvements. Quantitative description of an airway tree consists in application of several steps: segmentation of the tree, skeletonization, decomposition and anatomical labelling, cross section generation and finally quantitative measurements. Each step needs to use different kinds of image processing algorithms. The most works were performed on different segmentation strategies, however skeletonization algorithms are still not enough tested and they require attention. Moreover, skeleton has very large impact on the quality of quantitative measurement of a bronchial tree. In the paper authors tested three skeletonization methods which are based on thinning - the most popular skeletonization approach. However, each algorithm uses different thinning strategy. The paper presents basic concepts of the algorithms and discussion about their primary features based on acquired results from real human CT images.

PL

Ilościowa analiza ludzkich drzew oskrzelowych jest wyzwaniem z punktu widzenia analizy i przetwarzania obrazów. Uzyskane do tej pory wyniki są ciągle niedoskonałe i wymagają ulepszeń. Ilościowa analiza drzew oskrzelowych składa się z kilku kroków: segmentacji drzewa, szkieletyzacji, dekompozycji drzewa i anatomicznego etykietowania, generacji przekrojów prostopadłych i na końcu dokonania pomiarów. Każdy z kroków wymaga użycia innych algorytmów przetwarzania obrazów. Najwięcej badań wykonano nad problemem segmentacji drzewa. Jednakże algorytmy szkieletyzacji są ciągle zbyt mało przebadane i wymagają większej uwagi. Co więcej, uzyskany szkielet ma bardzo duży wpływ na jakość dokonanych pomiarów. W artykule, autorzy przetestowali trzy algorytmy szkieletyzacji bazujące na pocienianiu - najbardziej popularnym podejściu do szkieletyzacji. Każdy z algorytmów wykorzystywał inną strategię pocieniania. Artykuł prezentuje podstawowe koncepcje algorytmów oraz dyskusje na temat ich podstawowych właściwości bazując na wynikach przeprowadzonych eksperymentów.

8

Skeletal curves of 3D astrocyte samples

Klette G.

Machine Graphics and Vision

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2008

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Vol. 17, No. 1/2

105-129

EN

The paper discusses the concept of simple (and non-simple) elements for the generation of topologic skeletons, their transformation into abstract curve graphs, and the analysis of such graphs. The definition of a branching index of a point on a curve is fundamental in curve theory (in Euclidean space), and leads to important subjects of curve analysis. This paper derives analogous notions, such as branching index, branch element, and junction, for digital curves, which allow us to introduce new concepts for analyzing complex digital curves in a 3D space. The paper provides new theoretical insights, and also discusses an application project (the description of astrocytes in 3D confocal images of human brain tissue). This work was originally initiated by a particular research project at the Medical School of The University of Auckland. Medical experts developed the hypothesis that features of astrocytes in confocal volume scans are useful for defining states between normal and abnormal tissue. The calculation of skeletal curves, as proposed and studied in this paper, provides a valuable tool for calculating such features.

9

Charakterystyka uszkodzeń powierzchniowych warstw gleby podczas zrywki drewna ciągnikami rolniczymi w trzebieżowych drzewostanach sosnowych

Sowa J. M., Kulak D.

Inżynieria Rolnicza

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2008

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R. 12, nr 1(99)

353-361

PL

Celem badań było określenie rozmiaru i poznanie cech charakterystycznych naruszeń pokrywy glebowej powstałych w trakcie wykonywania zrywki drewna za pomocą ciągników rolniczych. Zakres prac ograniczono do niżowych, trzebieżowych drzewostanów sosnowych. Zrywka drewna w trzebieżach wczesnych spowodowała zniszczenia pokrywy glebowej na 2,57% powierzchni zrębowej, a w późnych na 3,63% zrębu. Dominującą formą uszkodzeń były ubicia, których udział w trzebieżach wczesnych wyniósł 84%, zaś w późnych 67%. Z przeprowadzonych analiz wynika, że o zaobserwowanych w badaniach różnicach w poziomie szkód w wierzchniej warstwie gleby pomiędzy trzebieżami wczesnymi i późnymi zadecydowała liczba powstałych naruszeń gleby, a nie powierzchnia pojedynczych uszkodzeń.

EN

The purpose of the research was to determine size and to get to know characteristic features of soil cover damage occurring during wood skidding with farm tractors. The scope of works was limited to lowland, thinning pine-stands. Wood skidding in first thinnings resulted in soil cover destruction at 2.57% of total felling area, and in secondary thinnings at 3.63% of total felling area. Compressions were prevailing form of damage. Their share in first thinnings reached 84%, and in secondary thinnings - 67%. Completed analyses indicate that differences in topsoil damage level between first and secondary thinnings, observed during the experiment, are determined by total number of soil damages, and not individual damage area.

10

A Fully-Automated Algorithm Dedicated to Computing Metacarpophalangeal and Interphalangeal Joint Cavity Widths

Zieliński B.

Schedae Informaticae

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2007

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Vol. 16

47-67

EN

In Europe, as well as in the United States of America, from 11\% to 14\% of residents suffer from rheumatoid arthritis. To give a diagnosis, an x-ray of patient's hand is taken, but regular analysis is exceedingly complicated, therefore it should be automated. It was not necessary to use a segmentation method. In order to find the joint cavity widths it was sufficient to use binarisation and thinning, and then analyze an obtained skeleton. The presented algorithm gives satisfactory results in the joint cavity width analysis (81% correct results).

11

Signature image recognition by shape context image matching

Adamski M., Saeed K.

Journal of Medical Informatics & Technologies

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2007

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Vol. 11

89--95

EN

This paper presents experiments on recognition of signature images. In preprocessing stage a thinning algorithm is used followed by a sampling technique. Sampled points are used to calculate shape context histograms and based on their values corresponding pairs of points from reference and tested signature objects are selected. A distance measure based on shape contexts is used to classify analysed signatures.

12

A comparative discussion of distance transforms and simple deformations in digital image processing

Klette G.

Machine Graphics and Vision

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2003

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Vol. 12, No. 2

235-256

EN

The paper discusses algorithms for extracting essential properties of binary objects in digital images which are either based on distance transforms defined by different metrics or algorithms based on simple shape deformations. Thinning algorithms define one-way simple deformations. Two-way simple deformations transfer object points into background points and vice versa, without destroying the image topology. This article reviews contributions in this area with respect to properties of algorithms and characterizations of simple points, and informs about a few new results. A main intention of this article is the comparative discussion of experimental results and theoretical equivalences.

13

VirEn : A virtual endoscopy system

Vilanova A., Konig A., Groller E.

Machine Graphics and Vision

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1999

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Vol. 8, No. 3

469-487

EN

Virtual endoscopy systems are promising tools for the simplification of daily clinical procedures. In this paper, a conceptual framework for a virtual endoscopy system (VirEn) is proposed, which is indented to be an interactive system. So far, out efforts have concentrated on some elements of the system. The generation of an optimal path for the automated navigation is one of them. Extensions to existing thinning algorithms used to generate the optimal path are presented and discussed. First results produced with VirEn are shown.