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Number of results: 64
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Abstract

The article presents results of tests performed at the AGH-University of Science and Technology in Cracow on strength of single-coil inductors used as tools in electrodynamic machining of pipes. The character of volumetric Lorentz forces acting on coils of compressing and expanding inductors was discussed, and numerically determined distributions of stresses and displacements created in coils under the impact of these forces were presented. The problems presented are relevant when designing durable inductors intended for industrial applications.

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Authors and Affiliations

Józef Bednarczyk
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Abstract

The subject of investigations was the fragment of low peatland complex located close to Miękinia,

about 30 km from Wrocław. Within the range of the examined area of peat bog complex there can be distinguished three parts differing in their utilization and composition of species, namely: 1/ the area degraded by the

attempt to afforest it with alder trees Alnus glutinosa (L.) Gaertner, 2/ occasionally used bog hay meadow and

3/ typical peat forming phytocenosis. Total number of determined species, belonging to 11 phytosociological

classes, ranged 77, out of which more than a half constitute representatives of Molinio-Arrhenatheretea class.

As far as a non-afforested area was concerned, there were determined 5 phytocenosis, including 4 classified as

peat forming ones and one typical for post-bog meadows (Alopecuretum pratensis). The afforested area featured

herbaceous plant composition which indicated that the area with Alopecuretum pratensis phytocenosis had been

degraded. Analysis of environmental requirements, done with the use of ecological numbers, proved that prevailing number of species characterize similar requirements. It was mainly afforested part to feature taxons of

broader ecological scale, e.g. Polygonum bistora L., Carex hirta L. and Plantago lanceolata L.

The afforested area was purchased by a private person, therefore it can be assumed that the reason for such

a way of peatlands utilization was obtaining EU subsidies at minimum work effort. A higher financial profit,

however, would have been made by the owner if he had maintained a bog area as an extensive meadow.

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Authors and Affiliations

K. Tomaszewska
K. Kołodziejczyk
M. Podlaska
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Abstract

The subject of the work is the analysis of thermomechanical bending process of a thin-walled tube made of X5CrNi18-10 stainless steel. The deformation is produced at elevated temperature generated with a laser beam in a specially designed experimental setup. The tube bending process consists of local heating of the tube by a moving laser beam and simultaneous kinematic enforcement of deformation with an actuator and a rotating bending arm. During experimental investigations, the resultant force of the actuator and temperature at the laser spot are recorded. In addition to experimental tests, the bending process of the tube was modelled using the finite element method in the ABAQUS program. For this purpose, the tube deformation process was divided into two sequentially coupled numerical simulations. The first one was the heat transfer analysis for a laser beam moving longitudinally over the tube surface. The second simulation described the process of mechanical bending with the time-varying temperature field obtained in the first simulation. The force and temperature recorded during experiments were used to verify the proposed numerical model. The final stress state and the deformation of the tube after the bending process were analyzed using the numerical solution. The results indicate that the proposed bending method can be successfully used in forming of the thin-walled profiles, in particular, when large bending angles and a small spring-back effect are of interest.

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Authors and Affiliations

J. Widłaszewski
M. Nowak
Z. Nowak
P. Kurp
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Abstract

The paper covers the research on the process of solutionizing of 7075 aluminum alloy in cold tools during the stamping of a high-strength structural element (B-pillar’s base). For technological reasons, in order to obtain high strength parameters of the 7075 alloy, it is necessary to carry out a solutionization process, which allows to obtain dispersion strengthening during ageing process. Properly performed heat treatment of the alloy increases the strength of the material to approx. 600 MPa. The combination of the process of solutionization with simultaneous shaping is aimed at improving and simplifying technological operations of aluminum alloy stamping, shortening the duration of the manufacturing process and reducing production costs. The manufactured lower part of the B-pillar will be used for the verification of the validity of the developed method. During the experiment, a series of stamping tests were carried out, in which the lubricants, pressure and position of the upper and lower blankholders were the variables. The obtained results allow to estimate the influence of the cooling conditions on the strength of the drawpieces obtained after the process of artificial ageing. In order to verify and analyse the results more quickly, a numerical simulation was carried out.

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Authors and Affiliations

K. Jaśkiewicz
M. Skwarski
S. Polak
Z. Gronostajski
ORCID: ORCID
J. Krawczyk
ORCID: ORCID
P. Kaczyński
W. Chorzępa
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Abstract

The paper presents methods of analytical and measurement-based determination of pressures acting on sheet metal in the process of electrodynamic forming by means of flat inductors generating pulse magnetic field. Pressures are determined for sheet metal of different thicknesses processed by means of circular and elliptical spiral inductors. The paper describes also examples of copper and aluminium sheet metal forming conducted by means of the analysed inductors and shaped forming dies.
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Authors and Affiliations

Józef Bednarski
Gerard Głuch
Andrzej Kot
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Abstract

The urban form creates the city structure, whose spatial values not only shape the functionality of the city, but also its identity, whose the most important determinant is the urban tissue. The subject of the study is the analysis of selected historical areas of Cracow in the scope of composition and readability of their urban structure. The analysis focuses on the identification of the most important aspects of spatial renewal processes of these spaces. These processes aimed at strengthening their potential as local centres, that can become a factor stimulating the development of the individual urban units. The increase in the attractiveness and quality of public spaces will positively affect the degree of their perception by the inhabitants and the social relations taking place in them. This in turn, influences the degree of the social involvement in development processes and the creation of more or less spontaneous, bottom-up activities.

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Authors and Affiliations

Dorota Jopek
ORCID: ORCID
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Abstract

Public spaces designed in a reasonable way make up an element that heals the city. They are both areas dedicated to collective recreation and a catalyst for social activities. Regarding a rational space exploitation, a reuse of grounds that are being liberated as a result of cities reorganization and revitalization of postindustrial areas should be a clue. The latter represent a unique esthetic virtues due to specificity of their original function. Comparison of the selected designs and scientific approaches had been made in order to take the floor in a debate about devastated areas revitalisation and city – and center-making capability of cultural investments. The importance of psychological links between human and his environment is set down by the presence of features defining the open form in a mentioned projects.

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Authors and Affiliations

Miłosz Zieliński
ORCID: ORCID
Ewelina Sypek
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Abstract

The article is devoted to an analysis of the suffixal and truncated suffixal variants of male Christian names in the Lutsk castle book of 1560‑1561(2013), and the identification of productive / unproductive formants in the composition of the researched names. The Polish academic I. Mytnik prepared a monograph Anthroponymy of Volynia of the 16th‑18th centuries (2010), using a wide source base – 58 manuscripts and 32 printed sources, but this 16th‑century Volyn literary heritage site did not serve as a basis for her study. Having studied the word‑formative derivatives of the male Christian names in the Lutsk castle book of 1560‑1561 we came to the conclusion that the most productive formants are ‑k(o) (67 variants) and ‑ets (40 variants); the suffixes ‑yna (10), ‑uk (9), ‑ash (6), ‑osh (4) show a slightly lower productivity. With the help of the suffixes ‑k(a), ‑yk, ‑ysh, ‑ut(a), ‑yts(a) 2 nominal variants are formed. Names with the formants ‑ok, ‑as, ‑ys, ‑os, ‑ay constitute single examples. The most commonly used names in Volyn documents from the middle of the 16th century were Yatsko / Ya(ts)ko (35 bearers), Fede(ts) / Khvede(ts) (22), Vasko / Va(s)ko (20), Hrytsko / Hry(ts)ko, Yvane(ts) (18), Le(v)ko (15), Andree(ts) / Andr± e(ts) (14), Yvashko / Yva(sh)ko, Matys (11), Mykhno, Tyshko / Ty(sh)ko, Fe(d)ko / Khve(d)ko (10). Among the truncated suffix name variants, the most productive form is ‑khno: it being attested in 9 names. While the most commonly used name is Mykhno (10 bearers).
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Authors and Affiliations

Lesya Yashchuk
1
ORCID: ORCID
Oksana Lytvynchuk
2
ORCID: ORCID

  1. Ivan Franko Zhytomyr State University
  2. Zhytomyr Polytechnic State University
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Abstract

Despite many technological possibilities, proper sanitation of sludge creates problems to their natural use. Thus, new solutions are still being looked for. Liming is one of the methods for sludge sanitation, however, rather expensive one. Seeking the substitute of high calcium content and non-toxic for environment has led to investigations on the application of mineral wastes - ashes from semi-dry sulfur removal from flue gases in the "Opole" power plant for sludge sanitation purposes. Ash was mixed with sludge in various proportions. After 3 days, the microbiological exams of the mixtures were carried out. The investigation data proved the performed sanitation effective and confirmed microbiological usability of the sludge for a natural use. The total contents of heavy metals and their distribution between particular fractions were determined in the sludge mixtures with mineral waste and in reference samples (i.e. sludge and mineral waste). No significant changes of metals proportion bound with biogenie fractions (fractions I- II) after addition of the mineral wastes to sludge were observed. Cadmium, zinc and partially chrome are bound with the iron and manganese oxides fraction (fraction III) which is sensitive to the redox potential changes. No significant change of contents was observed with the increase in a contribution of sludge or mineral waste. In all samples of the organic fraction (fraction IV) chrome and copper are bound in the highest amounts, and in the residue fraction (fraction V) cadmium, nickel and lead are bound, mainly. The investigation has showed that addition of optional proportions of sludge and mineral wastes mixtures into soil did not result in increase in heavy metals hazard. The investigation of the metals speciation in sludge and their mixtures with the mineral wastes showed similar metals distribution in individual fractions. The most hazardous elements for soil, water and plants such as lead, chrome, nickel, cadmium and zinc are bound in slightly soluble fractions and thus are hardly available to the ecosystem.
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Authors and Affiliations

Czesława Rosik-Dulewska
ORCID: ORCID
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Abstract

When and where did life first appear on Earth? Humankind has been pondering this question for centuries. The discovery of ancient microalgae is providing a partial answer.

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Authors and Affiliations

Józef Kaźmierczak
Barbara Kremer
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Abstract

A new approach to the transformations of the matrices of linear continuous-time systems to their canonical forms with desired eigenvalues is proposed. Conditions for the existence of solutions to the problems were given and illustrated by simple numerical examples.
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Authors and Affiliations

Tadeusz Kaczorek
1
ORCID: ORCID

  1. Bialystok University of Technology, Białystok, Poland
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Abstract

The main aim of the study is an assessment of models suitability for steel beams made of thin-walled cold-formed sigma profiles with respect to different numerical descriptions used in buckling analysis. The analyses are carried out for the sigma profile beam with the height of 140 mm and the span of 2.20 m. The Finite Element (FE) numerical models are developed in the Abaqus program. The boundary conditions are introduced in the formof the so-called fork support with the use of displacement limitations. The beams are discretized using S4R shell finite elements with S4R linear and S8R quadratic shape functions. Local and global instability behaviour is investigated using linear buckling analysis and the models are verified by the comparison with theoretical critical bending moment obtained from the analytical formulae based on the Vlasow beam theory of the thin-walled elements. In addition, the engineering analysis of buckling is carried out for a simple shell (plate) model of the separated cross-section flange wall using the Boundary Element Method (BEM). Special attention was paid to critical bending moment calculated on the basis of the Vlasov beam theory, which does not take into account the loss of local stability or contour deformation. Numerical shell FE models are investigated, which enable a multimodal buckling analysis taking into account interactive buckling. The eigenvalues and shape of first three buckling modes for selected numerical models are calculated but the values of critical bending moments are identified basing on the eigenvalue obtained for the first buckling mode.
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Authors and Affiliations

Katarzyna Rzeszut
1
ORCID: ORCID
Ilona Szewczak
2
ORCID: ORCID
Patryk Różyło
3
ORCID: ORCID
Michał Guminiak
4
ORCID: ORCID

  1. Poznan University of Technology, Institute of Building Engineering, Marii Skłodowskiej-Curie 5, 60-965 Poznan
  2. Lublin University of Technology, Faculty of Civil Engineering and Architecture, ul. Nadbystrzycka 38D,20–618 Lublin, Poland
  3. Lublin University of Technology, Faculty of Mechanical Engineering, ul. Nadbystrzycka 38 D, 20–618 Lublin, Poland
  4. Poznan University of Technology, Institute of Structural Analysis, Marii Skłodowskiej-Curie 5, 60-965 Poznan, Poland
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Abstract

In the paper the results of experimental research of the process of flow forming of cylindrical drawpieces were presented. The drawpieces were made of the 3.1 mm thick AMS 5596 sheet by drawing process. Tests were performed on two-roller metal spinning machine of a vertical axis Leifeld SFC 800 V500.

The main purpose of this research was to determine the relationship between relative thickness reduction and the mechanical properties of tested material. Knowledge of these dependencies is especially useful in designing machines’ components manufactured by flow forming, in the selection of parameters of realization of this technological process as well. Mechanical properties were determined on the basis of uniaxial tensile of the micro samples obtained from the drawpieces: (I) after cold flow forming, (II) after cold flow forming and in-process heat treatment. Obtained results were shown graphically in the diagrams and their analysis was carried out. In addition, the microstructure of the sheet material tested after drawing and flow forming is presented.

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Authors and Affiliations

S. Kut
P. Maj
T. Mrugała
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Abstract

The study proposed the model of “guide mark” defects formation on the internal surface of pipes, produced on PRM mills of PRP – 140. The research of pipe forming at plug rolling mill with stub mandrel has been carried out; regularities of the dimensionless parameters characterizing the deformation of the gap release, depending on the reduction ratio, were determined. The model of “guide mark” defect formation on the internal surface of the pipe has been proposed. This allows for lesser wall thickness variation of rough tubes. It has been shown that, when using dioctahedral pass designs in comparison with hexagonal pass designs the proportion of displaced volume along the pipe axis is greater but the value is lower; thereby, the risk of “guide mark” defect forming is reduced.

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Authors and Affiliations

D. Pavlov
A. Bogatov
E. Pavlova
H. Dyja
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Abstract

This study presents a description of the mechanics of forming dough pieces into cylindrical (cylinder-like) shapes. Based on the configuration of forming, the movement of the formed piece and its surface deformations were described. Kinematic relationships concerning the dough piece material as a rheological fluid were formulated. Next, the relationships coupling the kinematic quantities present with both descriptions were determined. The components of the deformation rate tensor, presented in the assumed forming configuration (cylindrical coordinate system), describe the velocity distribution on the surface of dough piece being formed and deformed. The determined kinematic quantities and their interrelations may be used to describe the process of forming dough pieces into cylindrical shapes.

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Authors and Affiliations

Feliks Chwarścianek
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Abstract

In this paper, the author derives theoretical formulae for calculating of squeezing forces. This report is the first one concerning the method of forming stepped shafts by longitudinal cold rolling. The formulae of the radial squeezing forces for the final passage of longitudinal rolling were calculated under the Huber hypothesis of plastic deformation and maximum shear stress.

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Authors and Affiliations

Marek Kowalik
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Abstract

The article is an introduction to the monographic content of a volume containing articles dedicated to contemporary models of building residential districts in Europe, where the issue of an attractive, beautiful architectural form must integrate the dimension of energy efficiency. Individualism must be subject to flexible regulations so that the current understanding of the concept of spatial order brings with it commonly desirable qualities as an effective strategy against the processes of the city›s sprawl. Attached is the output of the HOPU-S URBACT II project (2007-2013), which became an inspiration for the topic.

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Authors and Affiliations

Gabriela Rembarz
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Abstract

This article is devoted to the official forms in the inflection of chosen toponyms in Poland and the variety of dialectal singular and plural place names. The variety of place names often diverges from the rules of language use, and causes language users problems. The toponyms have peculiar, locally used inflected forms; the outside-linguistic (non-linguistic) factors that are social and local factors, play an important role in the inflection of place names. The local population often uses other forms than those recommended by official sources. I focus my attention on the genitive forms of toponyms because it is mainly here that one can see clear variations in the official and local inflection of place names. The material shows that the singular masculine toponyms have genitive endings: -a (in the official variety), -u (in the local variety), for example Biłgoraj, gen. Biłgoraja, but in the local dialect: biłgoraju. The singular feminine place names have genitive endings: -ej (in the official variety), -y||-i (in the local variety): Brzezowa, gen. Brzezowej, but Brzezowy in the local dialect. The plural toponyms have genitive endings: -ø, -ów, -i (-y), but in the local circulation the ending -ów is dominant and demonstrates a wider expansion in use. For example Brzózki, gen. Brzózek, in the local variety Brzuskuf; Budy, official gen. Bud, but Buduf; Burnie, gen. Burni, in the local dialect: Burniuf. The gathered material reflects a hesitation in the inflection of toponyms, as the linguistic customs and presented dialectal records of forms of genit ives of place names show a significantly diverse approach towards the Polish language.

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Authors and Affiliations

Iwona Nobis
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Abstract

There is estrimated more than 750 (public and privat) hospitals active In Poland. In spite that there is legal regulation concerning hospital projects, realization and equipment – permanent financial problems concerning a public health service, results in standards of hospitals, much worse then represented in hospitals in highly developed countries. A long – term practice of authors, concerning both, design and implementation of hospitals, let them to formulate a set of remarks about disfunction, influalcing growth of a danger, risks and mistakes in medical practice, also unexpected accidents.

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Authors and Affiliations

Jacek Orłowski
Andrzej Walkowski
Maciej Złowodzki
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Abstract

A meadow, a flowery meadow, a clearing, a lawn – smoothly trimmed, flat and recessed, a grassy pathway – these are elements of gardens that have been known for centuries, used in different styles and different types of gardens, including in public spaces. Pratum commune, commons or grassy mounds are the landmarks of the landscape of many a city, both currently and throughout history. Decorative grasses, such as pampas, Miscanthus or Pennisestum started to be used in garden compositions in XIX-century England. Initially more so due to their peculiarity than beauty. However, it was naturalism that gave rise to the wider use of grasses in gardens and parks in various places of the world and gained many propagators, including W. Robinson, J. Jensen K. Foerster and P. Oudolf.Grasses are currently often designed by landscape architects in urbanised spaces. They are employed both in geometric and freeform compositions. Their texture and delicate colour create a background for more expressive plants. They often constitute the key element of naturalist layouts, and the use of domestic species aids in preserving biodiversity and recreating the domestic landscape. Many of these current projects have been discussed in magazines and subject literature and have received awards in competitions. This review article is devoted to this subject.

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Authors and Affiliations

Agata Zachariasz
Halina Lipińska
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Abstract

This article discusses the multi-threaded and multi-dimensional process of preparing a technical designs that lead to the introduction of new forms of use into existing urban and architectural structures of high historical value. It covers research concerning formal and spatial determinants, associated with local law in selected European countries. Its results point to concise, precise and easily understandable provisions in terms of local law concerning planned development in areas under heritage conservation, which is conducive to a climate of social acceptance of constraints and prohibitions that — some — may consider significant.
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Authors and Affiliations

Janusz Barnaś
1

  1. Cracow University of Technology, Faculty of Architecture Institute of Urban and Regional Development
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Abstract

The author tries to explain what consequences for social morality ensue from the assumption that moral attitudes are expressed not only in words but also in reactive attitudes. P.F. Strawson assumes that acts of resentment can alter attitudes of those who have triggered them by their behavior. On the other hand, we are ready to control our outbursts of short temper and anger to a certain degree if we take into account agents’ motives and their limited ability to exercise self-control. Moreover, it seems that reactive attitudes – though less precise than verbal rebuke – are more frank and straightforward. Nevertheless, why must I, when I hear a mediocre academic researcher brag over and over again about his apparently essential contribution to philosophy, curb my moral assessment of his self-importance to the level of my irritation? Why should I feel constrained to keep my moral disgust in tune with my impatience mixed with amusement? Why shouldn’t I continue to believe that I can be an amiable character and a rigorous moral person at the same time?

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Authors and Affiliations

Jacek Hołówka
ORCID: ORCID
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Abstract

In contrast to foreign combining forms, native combining forms are usually treated as elements on the margin of German word formation. At the same time the question is under discussion, how the notion of combining form has to be defined. Based on a semantically oriented notion, as presented in reference books, and using a large sample of items, it is argued that elements like SCHWIEGER(vater), STIEF- (kind), (Vogel)KUNDE, (Hallen)WART are just the often mentioned examples of a category with a broad range of elements and with communicative relevance. Native combining forms are not only remains of former language periods, but are permanently produced by language users in order to meet their communicative needs.
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Authors and Affiliations

Josef Schu
1
ORCID: ORCID

  1. Universität des Saarlandes, Saarbrücken

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