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1

EGYPTIAN SEPULCHRAL PORTRAITS FROM THE 1ST-4TH C. AD (Portret sepulkralny z terenów Egiptu w I-IV w. n.e.)

100%

Baran M.

Kwartalnik Historii Kultury Materialnej

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2010

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tom 58

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nr 3-4

335-348

EN

The article is concerned with the varied terminology applied in the literature on the so-called Faiyum portraits. It discusses the terms most commonly used in publications, explains their origin and meaning, and finally suggests how they should be applied or what they should be replaced with. In both older and newer literature of the subject we can find several terms referring to Egyptian sepulchral pictures. They are often used interchangeably and inconsistently. The most frequent term is the 'mummy portrait', linking two-dimensional Faiyum paintings with mummies and with funeral rites, which does not seem accurate since the question of their sepulchral function has not yet been settled. The term is also used with reference to three-dimensional gilded and cartonnage masks from a different period. Apart from the term 'mummy portrait' there is a widely used notion of 'Faiyum portraits', which is derived from the Faiyum Oasis, where the first examples of portraits dated to the 1st-4th c. CE were found. Nowadays we know of specimen of such portraits from all over Egypt and from other territories. Another term is the 'coffin portrait', which is clearly wrong, as the portraits in question were never attached to coffins. Some terms applied to Faiyum portraits are connected with the painting technique or the material. For example the term 'encaustic portrait' refers to the technique of painting with wax on an unprimed surface, while the 'tempera portrait' was painted on a primed surface with tempera paints. Those notions, as well as the term 'easel portrait', are certainly overused and applied interchangeably with the term 'mummy portrait', although the works in question were also painted with other media and on varied surfaces. It should be stressed that not all funeral portraits painted on canvas and included in the Faiyum group were directly connected with mummies. In the relevant period in Egyptian funeral rites in addition to shrouds and mummy portraits there was a place for draperies, which decorated the tomb during burial feasts; they showed the deceased person in the company of Anubis and Osiris. In order to clarify the terminology concerning the Egyptian painting of the 1st-4th c. it is necessary to use certain terms consistently in certain contexts. Egyptian painting can be divided into several groups: pictures on everyday items, wall paintings, pictures on canvas and papyrus (including wall draperies, funeral draperies and illuminations of magic texts) and easel paintings. It is the last group that should include propaganda portraits, satirical and genre painting, religious pictures and commemorative images, with a separate category for imagines clipeatae, imagines maiorum and the images of family members in altars, which in various publications have been included in the category of mummy portraits (e.g. in K. Parlaska's catalogue). The meaning of the traditional term 'Faiyum portraits' should be narrowed to two-dimensional portraits painted on wood (panel portraits) and on canvas, including portraits showing only the face of the deceased person, portraits attached to mummies and funeral shrouds. The category should not include draperies. The terms which refer to the origin, authorship or addressees of this type of painting, such as 'Greco-Egyptian portraits' or 'Roman-Egyptian portraits' should be abandoned due to the complexity of the issue. The consistent application of the terms presented will allow scholars to avoid categorizing together artefacts of different function, origin, technique, character and chronology.

2

Mechanical Tests Applied to Structural Health Monitoring: An Overview of Previous Experience

51%

Baran M. , Nowakowski D. , Lisiecki J. , Kłysz S.

Fatigue of Aircraft Structures

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2020

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tom Iss. 12

123--135

EN

Laboratory for Materials Strength Testing (LMST) has been conducting accredited mechanical research for aviation from 2003. Among accredited procedures are e.g. low and high cycle fatigue tests, fracture toughness tests and fatigue crack growth rate tests. The main goal of them is obtaining materials constants and characteristics. However knowledge how to conduct these tests could be used also in other applications, for instance in the work on development of Structural Health Monitoring systems (SHM). When cracks propagate in a controlled way in laboratory conditions, it allows verifying the operation of a single sensor or a network of sensors. In this paper, an overview of mechanical tests carried out at the Laboratory for Materials Strength Testing within Air Force Institute of Technology (AFIT) work on research and development of SHM systems is presented. Specimens prepared from materials such as aluminum alloys (among other withdrawn PZL-130 Orlik TC-II aircraft) and CFRP composite were tested under different mechanical loads, i.e., cycle and impact loads. In the presented research, both constant amplitude and spectrum loads were applied.

3

Comparative Study on Fatigue Life of CFRP Composites with Damages

51%

Baran M. , Synaszko P. , Lisiecki J. , Kłysz S.

Fatigue of Aircraft Structures

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2019

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tom Iss. 11

28--38

EN

In this work, the compressive residual strength tests results, Compression After Impact (CAI), are presented. The specimens were made of carbon-epoxy prepreg E722-02 UHS 130-14. Two variants of specimens were tested: samples undamaged and samples with damage that was centrally introduced by a drop-weight impact, as per the ASTM D7136/7136M standard. An impactor with potential energy equal to 15J and the type of support required by the standard were used. The size of impacted damages, defined as an area of damage on a plane perpendicular to the impact direction, and the equivalent diameter were specified using the flash thermography method. The tests were performed using the fixtures manufactured according to the ASTM D7137/7137M standard. The specimens were compressed to determine the residual strength. This value was afterwards used to specify the force levels for the fatigue tests. The fatigue tests were carried out under force control – with a sinusoidal shape, stress ratio R equal to 0.1 and frequency f 1Hz. Maximum force in a loading cycle Pmax was being increased after each thousand of cycles N until its value was close to the residual strength determined in the previously mentioned tests. In this work, the following relationships were presented: force-displacement P-δ for both static and fatigue tests and displacement-loading cycles δ-N for fatigue tests. A method of conducting the fatigue tests of CFRP composite was proposed, in which both the CAI specimens and CAI fixture were used. This allowed researchers to accelerate making initial comparisons between the two groups of specimens with damages – grouped relative to the way of conditioning.

4

Examination of Honeycomb Core Compliance in Sandwich Structure

45%

Nowakowski D. , Baran M. , Lisiecki J. , Kłysz S. , Synaszko P.

Fatigue of Aircraft Structures

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2019

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tom Iss. 11

19--27

EN

The objective of the research presented in this paper was to determine the honeycomb core compliance of a sandwich structure of the horizontal stabilizer of the MiG-29 fighter jet in the static compression test. The study of the specimen was conducted based on the ASTM C365/C365M standard. The article presents the results of experimentally determined dependencies and strength parameters, i.e. the force-displacement dependence, the compressive modulus and the honeycomb core deformations.

5

Crack Propagation Tests for Load Sequences Developed Using Different Flight Parameters of a Trainer Aircraft

38%

Reymer P. , Kowalczyk K. , Baran M. , Nowakowski D. , Dziendzikowski M. , Leski A.

Fatigue of Aircraft Structures

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2023

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tom Iss.15

155--165

EN

Military aircraft are subjected to highly variable and unpredictable loads due to diverse mission profiles, armament configurations, and individual piloting styles. This variability complicates the definition of precise load spectra, particularly in cases where data loss occurs due to Flight Data Recorder (FDR) malfunctions or data mishandling. This paper investigates the use of different flight parameters, such as load factor (nz), barometric height (Hb), and horizontal velocity (Vp), to define load sequences for the PZL-130 “Orlik” TC-II military trainer aircraft. These sequences were then used to evaluate crack propagation using Compact Tension (CT) specimens. The results show that the incorporation of additional flight parameters improves the accuracy of crack propagation predictions when compared to direct strain measurements. This study highlights the potential of using available flight data to develop reliable load spectra for fatigue life estimation in military aircraft, even when direct load measurements are not financially feasible.