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  • Author: Wojciech Zieliński x
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A Remark on the Interpretation of Pooling Results

A Remark on the Interpretation of Pooling Results

A multinomial distribution (-1, π1), (0, π2), (1, π3), π1 + π2 + π3 = 1 is observed. Suppose that n 1 values -1, n 2 values 0 and n 3 values 1 (n = n 1 + n 2 + n 3) were observed. The construction of the confidence region for the vector (π1, π2, π3) is given. Theoretical considerations are illustrated by an example of the results of a pool.

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Sedimentary record of a Pleistocene ice-sheet interlobate zone (NE Poland)

Sedimentary record of a Pleistocene ice-sheet interlobate zone (NE Poland)

Well developed NE-SW trending corridors of outwash in NE Poland are associated with a series of lakes with a similar direction of elongation. The glaciofluvial corridor under study consists of parallel ridges with associated channels and kames. The deposits are flanked by till and hummocky terrain. The gravel ridges are composed of sand and gravel deposits that are cross-stratified, massive or graded, and that contain cut-and-fill structures and large intra-clasts of sand and gravel. Locally the deposits show normal faults. The succession of one of the ridges is interpreted to reflect the infilling of a braided channel in a crevasse. Sedimentation took place in some phases when the ice-sheet regime changed from active to stagnant. Sandy-gravel ridges occur within this complex perpendicular to the Weichselian ice-sheet margin.

The corridor is interpreted as an interlobate area in the zone between the Warmia and Mazury ice lobes. The braided-channel deposits are not comparable to typical Polish sandurs. The lithofacies characteristics show higher energy conditions, and the channels are deeper than those typical of Pleistocene lowland sandurs. The sand and gravel ridges are interpreted as interlobate eskers.

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Influence of source data on fatigue estimation of a fighter aircraft

Abstract

Aircraft structures during operation are exposed to fluctuating loads caused both by aerodynamic and inertial loads. This fluctuation leads to the creation of fatigue cycles, which gradually diminish the residual durability of the structure. During the design process, the flight envelope is defined as well as the design load spectrum, which then defines the durability of the structure (often expressed in means of flight hours). However, during the operation of an individual aircraft the actual load cycles can be significantly lower or higher than the designed; therefore, load monitoring is essential for safe operation of aircraft structures.

The following article shows the results of fatigue analysis based on flight data from different flight data recorders for the Su-22 fighter aircraft.

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The Verification of the Technical Conditions of a Combat-Trainer Jet’s Airframe

Abstract

The combat-trainer jet aircraft is an important element in the process of fighter pilot training. This type of aircraft provides a means of transition from basic training on low-speed propeller trainers to piloting high-speed and highly maneuverable fighter aircraft. Nowadays, in Poland, the PZL TS-11 “ISKRA” jet trainers, designed in 1960s, are employed for training purposes. Because of financial considerations this trainer hasn’t been yet replaced by modern aircraft that conforms to current specifications and needs.

As is the case with other aircraft in service of the PLAF, the TS-11 fleet has a large reserve of remaining Hourly Service Life (HSL). This opens an opportunity to extend the Calendar Service Life (CSL), so as it matches the HSL. To this end, a series of technical and research activities needed to be undertaken. The Air Force Institute of Technology is conducting the necessary verification of airframe structural conditions in cooperation with the Military Aviation Works No. 1 J.S.C. (branch in Dęblin) responsible for the overhaul and repair operations.

The AFIT’s activities in this program include:

  • deformation analysis of the selected surface areas of the wing and the fuselage;
  • assessment of hidden corrosion in riveted joints;
  • non-destructive testing of selected riveted joints.

This paper describes the deformation analysis. As of today, the first stage of the deformation inspection has been completed. At this stage, baseline surface measurements were obtained. Further inspections shall be performed cyclically. The future measurements will be used to establish the areas that deform due to the aircraft operation.

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Evaluation of pollen fertility in pepino (Solanum muricatum Ait.)

Abstract

The influence of the cultivation time (spring-summer and autumn) and the kind of cultivation (on rockwool and peat) on the fertility of pollen coming from three successive trusses were studied for six different pepino clones. The fertility was defined in vitro as the capacity of pollen for germinating. The average capacity of pollen germination ranged in the studied clones from 10 to 15%. These clones displayed the highest pollen fertility in an autumn cultivation, comparing to a spring-summer one. Higher rate of pollen fertility was observed during a springsummer cultivation on first trusses in most of the clones studied. The pollen of all plants grown on rockwool was more fertile, comparing to the cultivation on peat substrate. High differences in pollen fertility of the clones were obtained

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The Concept of a Full Scale Fatigue Test of a Su-22 Fighter Bomber

Abstract

This article presents a concept of the full scale fatigue test of a Su-22 fighter bomber. The authors define the general concept and goals of the test as well as the tasks to be accomplished in the preparation stage. The current work status is summarized and future tasks are defined.

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Predictive Models for Transient Loads of the Vertical Stabilizer of an Aircraft developed using Canonican Correlation Analision

Abstract

Knowledge about loads occurring in the structure during aircraft operation is vital from the point of view of the damage tolerance approach to aircraft design. In the best-life scenario, such information could be available from a network of sensors, e.g. strain gauges, installed in the aircraft structure to measure local stresses. However, operational loads monitoring (OLM) systems are still not widely applied. Instead, what is available is a set of flight parameters, which by the laws of inertia and aerodynamics help determine the dominant part of loads acting on a given element. This paper discusses the canonical correlation analysis (CCA) as a method for selecting the flight parameters used to predict aircraft loads. CCA allows for the identification of both different modes of stress distribution as well as flight parameters which are best suited for their prediction. The paper presents the application of this method to identify loads acting on the vertical stabilizer of an aircraft.

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Spatial variability of selected physicochemical parameters within peat deposits in small valley mire: a geostatistical approach

Abstract

Geostatistical methods for 2D and 3D modelling spatial variability of selected physicochemical properties of biogenic sediments were applied to a small valley mire in order to identify the processes that lead to the formation of various types of peat. A sequential Gaussian simulation was performed to reproduce the statistical distribution of the input data (pH and organic matter) and their semivariances, as well as to honouring of data values, yielding more ‘realistic’ models that show microscale spatial variability, despite the fact that the input sample cores were sparsely distributed in the X-Y space of the study area. The stratigraphy of peat deposits in the Ldzań mire shows a record of long-term evolution of water conditions, which is associated with the variability in water supply over time. Ldzań is a fen (a rheotrophic mire) with a through-flow of groundwater. Additionally, the vicinity of the Grabia River is marked by seasonal inundations of the southwest part of the mire and increased participation of mineral matter in the peat. In turn, the upper peat layers of some of the central part of Ldzań mire are rather spongy, and these peat-forming phytocoenoses probably formed during permanent waterlogging.

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Geomorphosite Assessment in the Proposed Geopark Vistula River Gap (E Poland)

Abstract

Geomorphosites are among major assets for the development of geotourism. An accurate assessment of spatial distribution of their scientific, educational and economic characteristics provides the basis for appropriate design and management of proposed geoparks. Although the problem of assessing their value for geotourism has been discussed by numerous authors, consistent methodology for the assessment of geomorphosites has not been devised so far. In the present study, we conducted a geotourist evaluation of geomorphosites located within the proposed geopark Vistula River Gap. We assessed a total of 76 sites using 18 assessment criteria. The results indicate not uniform spatial distribution of sites having the highest value. The application of cluster analysis to evaluation results enabled us to distinguish groups of sites with similar characteristics and thus to identify groups of geomorphosites in relation to which various measures should be taken in order to increase the possibilities of their tourist use.

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Vascular Complication in Aesthetic Medicine Treated with Hyperbaric Oxygenation

Abstract

The most hazardous adverse reactions following hyaluronic acid injections in aesthetic medicine involve vascular complications, known as the Nicolau Syndrome. This article presents a vascular complication in the area of the upper part of the nasolabial fold following subcutaneous administration of 0.5 ml of hyaluronic acid. At the time of the injection, paling occurred, which was followed by livedo racemosa appearing an hour later. Upon the lapse of a week, an ulceration appeared. It was not until the tenth day after the hyaluronic acid injection that hyaluronidase was administered. After 15 hyperbaric oxygen exposures, the ulcer was completely healed

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