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Number of results: 91
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Abstract

On one hand, Judgment and Decision Making (JDM) research reports a phenomena called the cross-modal effect, which shows that magnitude priming based on spatial attributes of a stimuli might influence numerical estimations. On the other hand, research directed at human cognition reports that processing of space and numbers may interfere. Despite different theoretical backgrounds, those two lines of research report similar results. Is it possible that the cross-modal anchoring and the interaction between space and number are just two manifestations of the same psychological effect, conceptualized within different paradigms? In Experiment 1 participants were asked to draw lines of different length and estimate numerosity of sets of dots presented for 100 ms. Based on current studies, magnitude priming is assimilated with subsequent numerical judgment. However, an unexpected contrast effect was observed in Experiment 1. Priming of “smallness” resulted in higher estimations of numerosity, while priming of “largeness” was associated with lower estimations. Short exposition time often leads to automatic attention processes, which could possibly account for the observed contrast effect. In Experiment 2 this assumption was tested, verifying potential differences between different exposition times (100 ms vs 300 ms). The same pattern of results was obtained. Findings of both experiments are discussed from the perspective of different anchoring paradigms and concepts related to space and number processing.

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Authors and Affiliations

Paweł Tomczak
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Abstract

A description of direct simulation of crosswind loads caused by critical vortex excitation and the response of the structure to these loads are presented in this paper. Tower-like structures of circular cross-sections are considered. A proposed mathematical model of vortex excitation has been numerically implemented and a selfserving computer program was created for the purpose. This software, cooperating with the FEM system, allows for a simulation of a crosswind load and lateral response in real time, meaning that at each time step of the calculations the load is generated using information regarding displacements seen beforehand. A detailed description of the mathematical model is neglected in this paper, which is focused on numerical simulations. WAWS and AR methods are used in simulations.

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Authors and Affiliations

T. Lipecki
A. Flaga

Authors and Affiliations

Katarzyna Kasia
1

  1. Department of Culture Theory, Faculty of Management of Visual Culture, Academy of Fine Arts in Warsaw
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Abstract

Due to different reasons a significant modal shift from railway to road transport took place over last decades. The basic reasons are pointed in the paper introduction together with contradicting transport policy taking into account environmental and economical challenges. Political vision to stimulate modal shift from road and air to railway cannot become true without achieving railway technical and operational interoperability. Paper describes wide range of technical barriers between individual intraoperable railway systems in civil engineering structures, traction power supply, control command and signalling and the ways, which are being applied to ensure stepwise converging of the technical solutions taking into account safety and technical compatibility, as well as other essential requirements, namely: reliability, accessibility, health and environment.

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Authors and Affiliations

M. Pawlik
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Abstract

Deriving the formulas for strain components, we are assuming, that cross-section of a rod being rotated in space during deformation does not need to be perpendicular to deformed centroid line. This not a quite intuitive assumption allows for more compact and easier formulas for strain tensor or equilibrium equations. Derived transformations between actual and initial coordinate system, components of strain tensor and virtual works principle for investigated spatially curved beams of bisymmetric cross-section are shown in this paper. Conformity with other models from referenced literature is also shown.

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Authors and Affiliations

R. Bijak
G. Kołodziej
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Abstract

The names of stations in the Way of the Cross may be used as titles of pictures and sculptures, each corresponding to a particular event in the Passion of Christ, or as titles of meditations. The article focuses on the second meaning, but the trends of the development of both kinds of names are similar. The study is based on material consisting of about 200 texts of the service that have been published from the beginning of the 20th century to the present (2020). The purpose of the article is to describe the changes that have taken place in the 20th century, a period of particularly turbulent changes in religious discourse. The article deals with the function, syntactic structure and features of style, such as the use of archaic or colloquial vocabulary. These properties are considered in connection with social and cultural changes. At the beginning of the analyzed period, it was customary to use relatively long titles, which informed the participant or reader about a particular event using expressive and evaluative lexis. Those titles gradually gave way to short, schematic names. Since the Second Vatican Council, titles of a new type have appeared. Their purpose is to attract the attention of the recipient. They are based on a riddle, a contrast, allusions, etc. Therefore, the recipient derives satisfaction from deciphering the puzzle or finding the source of the quote or allusion. These phenomena are known from research on the language of press or fiction, but they can also be linked to current trends in the so-called new evangelization.

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Agnieszka Sieradzka-Mruk
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Abstract

Edith Stein is a person who was born in the Jewish traditionally religious family. In her youth she lost her faith in God. However in her life she was seeking the truth. In this search she was very honest. The article first shows different definitions of truth. Then he takes the presentation of Edith Stein’s, the ways of phenomenological discov-ery of the truth about a human person. Finally, it shows her coming to the discovery of the God of Love, who has drawn her to mystical union in the spirituality of Carmel. Edith Stein died in the concentration camp in Auschwitz, experiencing the mystery of the Cross of Christ and sacrificing herself for her people.

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Authors and Affiliations

Ks. Andrzej Pryba MSF
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Abstract

ABSTRACT:

Among the cross pennies of later types, contained in the hoard from Słuszków near Kalisz and dated to after 1105, there are 73 obols — coins worth half a penny. The coins from the Słuszków hoard are dated to the period from the second half of the 11th century to the beginning of the 12th century. The assemblage is dominated by specimens with the image of a beaded cross and individual coins featuring a simple cross, a crosier as well as a crosier, a ring and a banner — types V, VI, VII and VIII according to M. Gumowski’s typology. Most probably, all the obols were struck by bishop’s mints in the archdiocese of Magdeburg.

SUMMARY:

In the early Middle Ages, the smallest denomination of coins used across Latin Europe was the obol. The most frequent finds of the coin, dated to the second half of the 10th century and the beginning of the 11th century come mainly from Germany, Bohemia and Hungary. The high silver content of the pennies at the time necessitated the production of smaller denominations, used for concluding small trade transactions, particularly in the countries where the coins’ origin. In the Polish lands small transactions involved predominantly fragments of coins, which constituted the dominant part of the hoard material from the times of Mieszko I and Boleslaus I the Brave. The debasement of pennies throughout the 11th century resulted in both obols and coin fragments disappearing from hoards. Almost of all of the late cross pennies CNP 813 and 867–869 from the Słuszków hoard, dated to the end of the 11th century and the beginning of the 12th century were not divided. The coins produced for the longest period of time (until the beginning of the 12th century) discovered in the Polish lands were cross obols. The largest collection of the coins comes from the hoard discovered in Słuszków near Kalisz and dated to after 1105. The assemblage contains 13061 coins, mainly early variants of cross pennies from the end of the 11th and the beginning of the 12th century.

Due to the lack of some types of cross obols in the most complete classification of the cross coins in Marian Gumowski’s Corpus Nummorum Poloniae, the typology based on the obols from the Słuszków hoard is presented.

The earliest variant, SoV-1, similar to CNP 674, has on its obverse the older version of the beaded cross (beads along the quadrangle). In all certainty, it is dated to before the half of the 11th century. Chronologically, the second type of obol in the Słuszków assemblage is the SoV-2 variant, not recorded in CNP. The artefact relates to a group of cross pennies from the so-called transitional group with a beaded cross, where some signs were arranged along the quadrangle and some along a circle. It may be dated to the half of the 11th century. The next five variants of cross obols, SoV-3 — SoV-7, are similar to CNP 677, their margins are wide enough for the legend to be legible. The obverse features the younger beaded cross, most often with 12 beads. The coins were minted in the third quarter of the 11th century. The next group of obols comprises variants SoV-8 — Sov-16, characterised by relatively narrow margins, which translates into only partial legibility of the characters. On the obverse there is the younger beaded cross. The obols may be dated back to the turn of the 4th quarter of the 11th century. The youngest group of cross obols from Słuszków are coins classified as variants SoV-17 — SoV-21. On the obverse they have a beaded cross with eight or nine beads. They may be dated to the last quarter of the 11th century. There are two more obols that may be identified as cross obols with beaded crosses, classified as variants SoVA-1 and SoVA-2. The specimens feature a beaded cross whose two arms are represented as prolonged triangles, similarly to the crossing of the crosier on the younger variants of type VII cross obols. In all probability, the coins may be dated to the turn of the 4th quarter of the 11th century. In the Słuszków hoard, the type VI cross obols with the simple cross are represented by one specimen of the SoVI-1 variant (CNP 876), dated probably to the last two decades of the 11th century.

The Słuszków hoard contains only one type VII obol — SoVII-1. The coin shows a short, crossed crosier, to the left, with a narrow crook, ending with a large dot. The coin may be dated to the last quarter of the 11th century. The last and probably the youngest group of obols comprises type VIII specimens of the SoVIII-1 type (CNP 1029). Obols of this type are known mostly from the Polabian region and can be dated to the end of the 11th and the beginning of the 12th century. In all certainty, all the cross obols from the Słuszków hoard were struck in Saxony, in mints of Magdeburg, Halle-Giebichenstein, Merseburg, Naumburg and perhaps Meissen, a fact confirmed by the artefacts discovered in Polabia. The large number of the coins known from Greater Poland — the region of Poland lying closest to Magdeburg, testifies to the Saxon origin of the cross obols from the end of the 11th and the beginning of the 12th century.

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Authors and Affiliations

Adam Kędzierski
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Abstract

A simple analytical method is developed to estimate frequencies of longitudinal modes in closed hard-walled ducts with discontinuities in a cross-sectional area. The approach adopted is based on a general expression for the acoustic impedance for a plane wave motion in a duct and conditions of impedance continuity at duct discontinuities. Formulae for mode frequencies in a form of transcendental equations were found for one, two and three discontinuities in a duct cross-section. An accuracy of the method was checked by a comparison of analytic predictions with calculation data obtained by use of numerical implementation based on the forced oscillator method with a finite difference algorithm.

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Authors and Affiliations

Mirosław Meissner
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Abstract

The objective of this study is to investigate the change in partition coefficient with a change in the concentration of the solute in a liquid system consisting of two relatively immiscible solvents. To investigate the changes in the partition coefficients, the data of the partition coefficients at infinite dilution and the ternary Liquid-Liquid Equilibrium (LLE) data at finite concentrations of the solute should be consistent. In this study, 29 ternary systems that are found in literature and for which the partition coefficients at infinite dilution and the ternary LLE data cannot be predicted accurately by the universal quasi-chemical (UNIQUAC) model are identified. On the basis of this model, some consistent and inconsistent ternary systems are introduced. Three inconsistent systems, namely hexane-butanol-water, CCl4 (carbon tetrachloride)-PA (propanoic acid)-water, and hexane-PA-water, are chosen for detailed analysis in this study. The UNIQUAC activity coefficient model is used to represent these data over a range of concentrations. The results show large errors, exhibiting the inability of this model to correlate the data. Furthermore, some ternary systems in which cross behavior of solutes between two phases observed are identified.

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Authors and Affiliations

Akand Islam
Anand Zavvadi
Vinayak Kabadi
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Abstract

This publication describes research on the course of the process of cross-linking new BioCo polymer binders - in the form of water-based polymer compositions of poly(acrylic acid) or poly(sodium acrylate)/modified polysaccharide - using selected physical and chemical factors. It has been shown that the type of cross-linking factor used influences the strength parameters of the moulding sand. The crosslinking factors selected during basic research make it possible to obtain sand strengths similar to those of samples of sands bonded with commercial binders. Microwave radiation turned out to be the most effective cross-linking factor in a binder-matrix system. It was proven that adsorption in the microwave radiation field leads to the formation of polymer lattices with hydrogen bonds which play a major role in maintaining the formed cross-linked structures in the binder-matrix system. As a result, the process improves the strength parameters of the sand, whereas the hardening process in a microwave field significantly shortens the setting time.
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Authors and Affiliations

B. Grabowska
A. Bobrowski
K. Kaczmarska
E. Olejnik
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Abstract

The effects of silica additive (Poraver) on selected properties of BioCo3 binder in form of an aqueous poly(sodium acrylate) and dextrin (PAANa/D) binder were determined. Based on the results of the thermoanalytical studies (TG-DTG, FTIR, Py-GC/MS), it was found that the silica additive results in the increase of the thermostability of the BioCo3 binder and its contribution does not affect the increase in the level of emissions of organic destruction products. Compounds from group of aromatic hydrocarbons are only generated in the third set temperature range (420-838°C). The addition of silicate into the moulding sand with BioCo3 causes also the formation of a hydrogen bonds network with its share in the microwave radiation field and they are mainly responsible for maintaining the cross-linked structures in the mineral matrix system. As a consequence, the microwave curing process in the presence of Poraver leads to improved strength properties of the moulding sand (���� �� ). The addition of Poraver's silica to moulding sand did not alter the permeability of the moulding sand samples, and consequently reduced their friability. Microstructure investigations (SEM) of microwave-cured samples have confirmed that heterogeneous sand grains are bonded to one another through a binder film (bridges).

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Authors and Affiliations

S. Cukrowicz
S. Żymankowska-Kumon
B. Grabowska
A. Bobrowski
D. Drożyński
K. Kaczmarska
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Abstract

This paper presents the results of the theoretical and practical analysis of selected features of the function of conditional average value of the absolute value of delayed signal (CAAV). The results obtained with the CAAV method have been compared with the results obtained by method of cross correlation (CCF), which is often used at the measurements of random signal time delay. The paper is divided into five sections. The first is devoted to a short introduction to the subject of the paper. The model of measured stochastic signals is described in Section 2. The fundamentals of time delay estimation using CCF and CAAV are presented in Section 3. The standard deviations of both functions in their extreme points are evaluated and compared. The results of experimental investigations are discussed in Section 4. Computer simulations were used to evaluate the performance of the CAAV and CCF methods. The signal and the noise were Gaussian random variables, produced by a pseudorandom noise generator. The experimental standard deviations of both functions for the chosen signal to noise ratio (SNR) were obtained and compared. All simulation results were averaged for 1000 independent runs. It should be noted that the experimental results were close to the theoretical values. The conclusions and final remarks were included in Section 5. The authors conclude that the CAAV method described in this paper has less standard deviation in the extreme point than CCF and can be applied to time delay measurement of random signals.

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Authors and Affiliations

Adam Kowalczyk
Robert Hanus
Anna Szlachta
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Abstract

Precise measurement of rail vehicle velocities is an essential prerequisite for the implementation of modern train control systems and the improvement of transportation capacity and logistics. Novel eddy current sensor systems make it possible to estimate velocity by using cross-correlation techniques, which show a decline in precision in areas of high accelerations. This is due to signal distortions within the correlation interval. We propose to overcome these problems by employing algorithms from the field of dynamic programming. In this paper we evaluate the application of correlation optimized warping, an enhanced version of dynamic time warping algorithms, and compare it with the classical algorithm for estimating rail vehicle velocities in areas of high accelerations and decelerations.

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Authors and Affiliations

Stefan Hensel
Marin B. Marinov
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Abstract

Since late 2011, porcine infections with highly virulent and antigenic variant of pseudorabies virus (PRV) cause great economic loss in the swine industry in China, and its emergence leads to variable protection efficacy of the commercially available PRV vaccine.

In the present study, the potential cross-protective efficacy of two live virus vaccines, includ- ing a commercial vaccine, and an attenuated low pathogenic PRV variant (rPRVTJ-delTK/gE/gI) against a PRV variant Tianjing (TJ) was evaluated in piglets. Vaccination of piglets with the live vaccine Bartha-K61 could not reduce the clinical signs, and was partially efficacious in the reduc- tion of viral loads upon PRV variant TJ challenge, indicating that this live vaccine provided limited cross-protection efficacy against the PRV variant infection. Additionally, rPRVTJ-delTK/gE/gI appeared to exert some beneficial efficiency in shortening the period of clinical fever and improv- ing the growth performance of the challenged pigs.

Our findings give a valuable guidance for the choice and use of PRV vaccines to control PRV variant infection in the field.

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Authors and Affiliations

M. Wang
L. Wang
Q. Zhao
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Abstract

A huge isolated accumulation, more than 3 m thick and 10 m wide, of densely packed, uncrushed brachiopods has been found in Józefka Quarry within the Middle/Upper Devonian Szydłówek Beds deposited in a relatively deep environment of an intrashelf basin (Kostomłoty facies zone, western Holy Cross Mountains, Poland). The low-diversity assemblage is strongly dominated by the atrypide Desquamatia globosa jozefkae Baliński subsp. nov. and, to a lesser degree, by the rhynchonellide Coeloterorhynchus dillanus (Schmidt, 1941), which constitute 72.8% and 22.1% of the fauna, respectively. Less frequent are specimens representing the genera Hypothyridina, Schizophoria and Phlogoiderynchus. According to the conodont fauna found within the coquina bed, the stratigraphic position of the shell accumulation is close to the Givetian/ Frasnian boundary. The brachiopods are associated with numerous crinoids and less frequent bryozoans, receptaculitids (Palaeozoic problematica), sponges and solitary corals. Although it is difficult to entirely exclude the autochthonous nature of the brachiopod coquina member, its allochthonous origin and redeposition of the brachiopod shells to the deep basin by gravity flows is much more probable. Such conclusion is supported by the following facts: (1) the position of the complex in a succession of deep-marine basinal facies impoverished in oxygen; (2) its lateral thinning-out and composite internal stratification; (3) the lensshaped geometry of the coquina bed in the section perpendicular to the bedding dip; (4) high variability of the sediments preserved within the shells; and (5) the preferred orientation of the shells. The brachiopods mixed with crinoidal debris were probably transported by low-velocity, high-density, gravity-induced debris flows. Lack of fossils typical of the Middle Devonian shallows, such as massive stromatoporoids, amphiporoids and tabulates, indicates that the source area of the bioclastic material was not located in the shallowest part of the shelf, but most probably on a submarine sea-mount to the north of present-day Józefka, as suggested by earlier investigators. The triggering mechanism of the allochthonous deposition was an earthquake rather than storm activity. The enormous thickness of the brachiopod complex is probably caused by the sinking of bioclastic material, transported in succeeding depositional multi-events, in a soft, muddy bottom, typical of the Szydłówek Beds deposition.

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Authors and Affiliations

Stanisław Skompski
Andrzej Baliński
Michał Szulczewski
Inga Zawadzka
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Abstract

The paper presents the methodology that makes it possible to evaluate computational model and introduce current corrections to it. The methodology ensures proper interpretation of nonlinear results of numerical analyses of thin-walled structures. The suggested methodology is based on carrying out, in parallel to nonlinear numerical analysis, experimental research on some selected crucial zones of loadcarrying structures. Attention is drawn to the determinants concerning the performance of an adequate experiment. The author points out on indicating the role of model tests as a fast and economically justified research instruments practicable when designing thin-walled load-carrying structures.

The presented considerations are illustrated by an example of a structure whose geometrical complexity and ranges of deformation are characteristic for modern solutions applied in the load-carrying structures of airframes. As the representative example, one selected the area of the load-carrying structure that contains an extensive cut-out, in which the highest levels and stress gradients occur in the conditions of torsion evoking the post-buckling states within the permissible loads. The stress distributions within these ranges of deformations were used as the basis for determining the fatigue life of the structure.

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Authors and Affiliations

Tomasz Kopecki
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Abstract

In this paper the authors present the test carried out to obtain the uniform velocity distribution at the outlet cross section of flow fan. In the investigations the inner flat vane mounted inside of the impeller has been applied. For various angular position of the inner vane, one obtained different flow structures as well as different velocity distributions. The analysis of the obtained results is presented in form of graphs shown in 10 figures, juxtaposing flow phenomena with velocity distributions. Numerical flow simulation with the use of Flo++ program based on the Finite Volume Method was carried out.

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Authors and Affiliations

Jolanta Stacharska-Targosz
Monika Chmielowiec
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Abstract

This paper presents an idea and results of 2D and 3D numerical CFD simulations of the proposed ring-engine construction dedicated for air propulsion or generation of electric power. The engine is designed as the simplest construction realizing the idea of pulsating reaction chamber utilizing a constant volume combustion principle. An atypical fuel (hydrogen peroxide) is used in the analyzed construction. The proposed ring-engine has reaction chambers forming a part of a ring periodically filled by cooling air and hydrogen peroxide vapour. The H2O2 is decomposed in exothermic reaction increasing pressure inside the chamber of constant volume. High pressure gas contents of the reaction chambers are periodically decompressed by jet nozzles generating torque. The paper contains the description of the ring-engine idea, the schematic engine geometry and a set of data visualizing pressure, velocity, temperature and species distribution inside the engine components being results of numerical simulations.

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Authors and Affiliations

Janusz Piechna
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Abstract

In order to solve the problem of large error of delay estimation in low SNR environment, a new delay estimation method based on cross power spectral frequency domain weighting and spectrum subtraction is proposed. Through theoretical analysis and MATLAB simulation, among the four common weighting functions, it is proved that the cross-power spectral phase weighting method has a good sharpening effect on the peak value of the cross-correlation function, and it is verified that the improved spectral subtraction method generally has a good noise reduction effect under different SNR environments. Finally, the joint simulation results of the whole algorithm show that the combination of spectrum subtraction and crosspower spectrum phase method can effectively sharpen the peak value of cross-correlation function and improve the accuracy of time delay estimation in the low SNR environment. The results of this paper can provide useful help for sound source localization in complex environments.

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Authors and Affiliations

Feng Bin
Xu Lei
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Abstract

In multi-axis motion control systems, the tracking errors of single axis load and the contour errors caused by the mismatch of dynamic characteristics between the moving axes will affect the accuracy of the motion control system. To solve this issue, a biaxial motion control strategy based on double-iterative learning and cross-coupling control is proposed. The proposed control method improves the accuracy of the motion control system by improving individual axis tracking performance and contour tracking performance. On this basis, a rapid control prototype (RCP) is designed, and the experiment is verified by the hardware and software platforms, LabVIEW and Compact RIO. The whole design shows enhancement in the precision of the motion control of the multiaxis system. The performance in individual axis tracking and contour tracking is greatly improved.

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Authors and Affiliations

Wan Xu
Jie Hou
Wei Yang
Cong Wang

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