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Number of results: 97
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Abstract

The lubrication of angular contact ball bearings under high-speed motion conditions is particularly important to the working performance of rolling bearings. Combining the contact characteristics of fluid domain and solid domain, a lubrication calculation model for angular contact ball bearings is established based on the RNG k-ε method. The pressure and velocity characteristics of the bearing basin under the conditions of rotational speed, number of balls and lubricant parameters are analyzed, and the lubrication conditions and dynamics of the angular contact ball bearings under different working conditions are obtained. The results show that the lubricant film pressure will rise with increasing speed and viscosity of the lubricant. The number of balls affects the pressure and velocity distribution of the flow field inside the bearing but has a small effect on the values of the characteristic parameters of the bearing flow field. The established CFD model provides a new approach to study the effect of fluid flow on bearing performance in angular contact ball bearings.
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Bibliography

[1] B. Yan, L. Dong, K. Yan, F. Chen, Y. Zhu, and D. Wang. Effects of oil-air lubrication methods on the internal fluid flow and heat dissipation of high-speed ball bearings. Mechanical Systems and Signal Processing, 151:107409, 2021. doi: 10.1016/j.ymssp.2020.107409.
[2] H. Bao, X. Hou, X. Tang, and F. Lu. Analysis of temperature field and convection heat transfer of oil-air two-phase flow for ball bearing with under-race lubrication. Industrial Lubrication and Tribology, 73(5):817–821, 2021. doi: 10.1108/ilt-03-2021-0067/v2/decision1.
[3] T.A. Harris. Rolling Bearing Analysis. Taylor & Francis Inc. 1986.
[4] T.A. Harris and M.N. Kotzalas. Advanced Concepts of Bearing Technology. Taylor & Francis Inc. 2006.
[5] F.J. Ebert. Fundamentals of design and technology of rolling element bearings. Chinese Journal of Aeronautics, 23(1):123-136, 2010. doi: 10.1016/s1000-9361(09)60196-5.
[6] T.A. Harris. An analytical method to predict skidding in high speed roller bearings. A S L E Transactions, 9(3):229–241, 1966. doi: 10.1080/05698196608972139.
[7] A. Wang, S. An, and T. Nie. Analysis of main bearings lubrication characteristics for diesel engine. In: IOP Conference Series: Materials Science and Engineering, 493(1):012135, 2019. doi: 10.1088/1757-899X/493/1/012135.
[8] W. Zhou, Y. Wang, G. Wu, B. Gao, and W. Zhang. Research on the lubricated characteristics of journal bearing based on finite element method and mixed method. Ain Shams Engineering Journal, 13(4):101638, 2022. doi: 10.1016/j.asej.2021.11.007.
[9] J. Chmelař, K. Petr, P. Mikeš, and V. Dynybyl. Cylindrical roller bearing lubrication regimes analysis at low speed and pure radial load. Acta Polytechnica, 59(3):272–282, 2019. doi: 10.14311/AP.2019.59.0272.
[10] C. Wang, M. Wang, and L. Zhu. Analysis of grooves used for bearing lubrication efficiency enhancement under multiple parameter coupling. Lubricants, 10(3):39, 2022. doi: 10.3390/lubricants10030039.
[11] Z. Xie and W. Zhu. An investigation on the lubrication characteristics of floating ring bearing with consideration of multi-coupling factors. Mechanical Systems and Signal Processing, 162:108086, 2022. doi: 10.1016/j.ymssp.2021.108086.
[12] M. Almeida, F. Bastos, and S. Vecchio. Fluid–structure interaction analysis in ball bearings subjected to hydrodynamic and mixed lubrication. Applied Sciences, 13(9):5660, 2023. doi: 10.3390/app13095660.
[13] J. Sun, J. Yang, J. Yao, J. Tian, Z. Xia, H. Yan, and Z. Bao. The effect of lubricant viscosity on the performance of full ceramic ball bearings. Materials Research Express, 9(1):015201, 2022. doi: 10.1088/2053-1591/ac4881.
[14] D.Y. Dhande and D.W. Pande. A two-way {FSI} analysis of multiphase flow in hydrodynamic journal bearing with cavitation. Journal of the Brazilian Society of Mechanical Sciences and Engineering, 39:3399–3412, 2017. doi: 10.1007/s40430-017-0750-8.
[15] H. Liu, Y. Li, and G. Liu. Numerical investigation of oil spray lubrication for transonic bearings. Journal of the Brazilian Society of Mechanical Sciences and Engineering, 40:401, 2018. doi: 10.1007/s40430-018-1317-z.
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Authors and Affiliations

Bowen Jiao
1
ORCID: ORCID
Qiang Bian
1
ORCID: ORCID
Xinghong Wang
1
Chunjiang Zhao
1
ORCID: ORCID
Ming Chen
1
Xiangyun Zhang
2

  1. School of Mechanical Engineering, Taiyuan University of Science and Technology, Taiyuan, China
  2. Luoyang Bearing Research Institute Co., Ltd, Luoyang, China
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Abstract

The experiment consisted in monitoring the count of moulds and three selected Trichoderma sp. isolates (T1 - Trichoderma atroviride, T2 - Trichoderma harzianum, T3 - Trichoderma harzianum) in vegetable (onion and tomato) waste composted with additives (straw, pig manure). Additionally, the aim of the study was to determine the type of interaction occurring between autochthonous fungi isolated from composts after the end of the thermophilic phase and Trichoderma sp. strains applied in the experiment. Number of microorganisms was determined by the plate method, next the identification was confirmed. The rating scale developed by Mańka was used to determine the type of interactions occurring between microorganisms. The greatest count of moulds in onion waste composts was noted in the object which had simultaneously been inoculated with two strains T1 - T. atroviride and T3 - T. harzianum. The greatest count of moulds was noted in the tomato waste composts inoculated with T2 - T. harzianum strain. Microscope identification revealed that Penicillum sp., Rhizopus sp., Alternaria sp. and Mucor sp. strains were predominant in onion waste composts. In tomato waste composts Penicillium was the predominant genus, followed by Rhizopus. The test of antagonism revealed the inhibitory effect of Trichoderma isolates on most autochthonous strains of moulds. Tomato waste composts proved to be better substrates for the growth and development of Trichoderma sp. isolates. The results of the study show that vegetable waste can be used in agriculture as carriers of antagonistic microorganisms.

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Authors and Affiliations

Agnieszka Wolna-Maruwka
Tomasz Piechota
Alicja Niewiadomska
Jacek Dach
Magdalena Szczech
Małgorzata Jędryczka
Agnieszka A. Pilarska
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Abstract

The authors studied the fracture mechanical properties under half-symmetric loading in this paper. The stress distribution around the crack tip and the stress intensity factor of three kinds of notched specimens under half symmetric loading were compared. The maximum tensile stress σmax of double notch specimens was much greater than that of single notch specimens and the maximum shear stress τmax was almost equal, which means that the single notch specimens were more prone to Mode II fractures. The intensity factors KII of central notch specimens were very small compared with other specimens and they induced Mode I fractures. For both double notch and single notch specimens, KII was kept at a constant level and did not change with the change of a/h, and KII was much larger than KI. KII has the potential to reach its fracture toughness KIIC before KI and Mode II fractures occurred. Rock-like materials were introduced to produce single notch specimens. Test results show that the crack had been initiated at the crack tip and propagated along the original notch face, and a Mode II fracture occurred. There was no relationship between the peak load and the original notch length. The average value of KIIC was about 0.602 MPa×m1/2, and KIIC was about 3.8 times KIC. The half symmetric loading test of single notch specimens was one of the most effective methods to obtain a true Mode II fracture and determine Mode fracture toughness.

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Authors and Affiliations

Zhi Wang
Jiajia Zhou
Long Li
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Abstract

The aim of the performed experiments was to analyse relationships occurring between endophytic

bacteria from the Herbaspirillum genus and Sinorhizobium meliloti Bp nodule bacteria and to examine the

condition of plants subjected to coinoculation with the above-mentioned strains in in vitro conditions. In experiments examining the impact of Herbaspirillum frisingense on Sinorhizobium meliloti BP, the stimulation of

growth of inoculated bacteria from the Sinorhizobium genus was recorded in all three combinations (48-hour

culturing, sediment and supernatant). On the other hand, the examination of interactions between the Sinorhizobium meliloti strain and Herbaspirillum frisingense strain revealed that in the case of culture and supernatant, an

antagonistic action was recorded. Besides, it was found that such coinoculation exerted a beneficial influence on

the process of seed lucerne symbiosis and yielding as confirmed by increased numbers of root nodules, higher

nitrogenase activity and greater plant mass.

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Authors and Affiliations

A. Niewiadomska
D. Swędrzyńska
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Abstract

Traffic related noise is currently considered as an environmental pollution. Paper presents results of multidirectional study attempting to serve urban traffic without the need to erect noise barriers interfering urban space. Initial concept of the road expansion included construction of 1000 m of noise barriers dividing city space. Improvement in the acoustic conditions after construction completion is possible due to the applied noise protection measures: vehicle speed limit, smooth of traffic flow, use of road pavement of reduced noise emission and the technical improvement of the tramway.

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Authors and Affiliations

K.J. Kowalski
A.J. Brzeziński
J.B. Król
P. Radziszewski
Ł. Szymański
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Abstract

The pesticide persistence, in particular in soils, often significantly exceeding the declarations of their manufacturers is surprising. There are many publications devoted to the explanation of this phenomenon in the field literature, but the diverse research methodologies used may lead to the ambiguous conclusions. On the basis of the collected literature, the attempt was made to systematize the available information on the interactions of commonly used groups of pesticides with individual soil components. The complex mechanisms of interactions between pesticides and soil based on van der Waals forces, ionic and covalent bonding, ligand exchange and charge transfer complexes formation were demonstrated. It was also proved that the nature of interactions is strictly dependent on the structure of the pesticide molecule. The conclusion of the review may contribute to the choice of plant protection products that, in addition to their effectiveness, are as little ballast for the environment as possible.

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Authors and Affiliations

Hanna Barchańska
1
Marianna Czaplicka
2
ORCID: ORCID
Joanna Kyzioł-Komosińska
2

  1. Silesian University of Technology, Poland
  2. Institute of Environmental Engineering, Polish Academy of Sciences
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Abstract

Despite many years of research, we have yet to discover all the myriad ways various components of the climate interact. For instance, it looks likely that the circulation of oceanic waters has a much broader impact than previously thought.

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Authors and Affiliations

Paweł Schlichtholz
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Abstract

A helicopter blade tip vortex generates impulsive noise of high intensity when it impinges upon the following blade. In the present work, the vortex is attenuated by coaxial swirling jet rotating in the opposite direction. The jet issues from a nozzle located at the blade tip. The nozzle was supplied with compressed air transported in the blade channel. The decrement of vortex strength is measured as a function of the compressed air pressure related to the dynamic pressure of the flow in the wind tunnel. It was found that the jet, even of relatively low intensity, considerably effects the blade tip vortex formation.
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Authors and Affiliations

Andrzej Szumowski
Mieczysław Litwińczyk
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Abstract

Nanotechnology is a manipulation of nature that has emerged through the use of basic sciences, material science and engineering at the nano-scale. The interaction between biological environment and nanoparticles-nanoparticles or nanoparticles-organic materials is not yet well-understood. The toxic effects of nanoparticles on plants were investigated and it was proved that they caused morphological and physiological changes in plants. This study aimed to determine the effects of TiO -TiO2Ag nanoparticles, and co-application of EDDS-TiO2Ag nanoparticles alone, co-application of ZnO nanoparticles- Ag nanoparticles on seed germination, seedling vigor, radicle and plumule elongation of two different wheat species. In the experimental stage, ten seeds were placed in petri-dishes with a double layer of fi lter paper which was used as an inert material. Then 5 mL of TiO2Ag, ZnO+TiO2Ag, and EDDS+TiO2Ag suspensions were added to every petri dish. Results showed that the maximum SVI was determined at the concentration of 50 mg∙L-1 TiO2 Ag+EDDS for bread wheat and the minimum SVI was observed at 100 mg∙L-1 TiO2Ag nanoparticles concentration for durum wheat. The effect of both nanoparticles-nanoparticles interaction and the other chemicals-nanoparticles interaction on the ecosystems should be evaluated.

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Authors and Affiliations

G. Doğaroğlu Zeynep
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Abstract

The model of odour intensity analyzer in a form of two layers of neurons. was proposed. The first layer consists of specific receptors of odorants, which are randomly distributed. The odorant influence on odour intensity of mixtures is depends on the number of suitable receptors and number of their connections with the second layer neurons (the degree of divergence). The second layer neuron is stimulated with the same power after receiving the signal from any receptor or receptors. Il was assumed that the odour intensity is directly proportional to the number of stimulated neurons in the second layer. The investigated model contained 1000 neurons in the first layer and 1456 neurons in the second layer. The first layer contained receptors A and B (RA and RB) in quantities 15% RA, IS% RB and 30% RA, 10% RB. Receptors A characterized the divergence I :9, receptors B - 1 :25. The stimulus were mixtures containing 5-100 molecules A and B per hundred (x , = 0.0, 0.2, 0.5, 0.8 and 1.0). The general similarity of • the model reaction with that of the human smell reaction was found.
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Authors and Affiliations

Joanna Kośmider
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Abstract

Automation in experiments carried out on animals is getting more and more important in research. Computers take over laborious and time-consuming activities like recording and analysing images of the experiment scene. The first step in an image analysis is finding and distinguishing between the observed animals and then tracking all objects during the experiment. In this paper four tracking methods are presented. Quantitative and qualitative figures of merit are applied to confront those methods. The comparison takes into consideration the level of correct object recognition during different disturbances, the speed of computation, requirements as to the frame rate and image illumination, quality of recovering from occluded situations and others.

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Authors and Affiliations

Magdalena Mazur-Milecka
Antoni Nowakowski
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Abstract

The paper presents selected results of studies connected with modeling of a biological object which could be used for simulation and measurements of the selected human tissues optical transmittance. The studies were performed for transilluminated homogeneous tissue layers as well as for objects consisted of different tissues. During simulations the software built with LabVIEW environment was used. Experimental verification of the model structure was made with spectrophotometry. The presented examples of modeling concern the transmittance spectra for two selected specific objects: the venous blood and muscle tissue analyzed in the wavelength range extending from 360 nm to 900 nm. The implemented model could be used in estimating the content and thickness of particular layers distinguished in a complex object and prediction of their transillumination efficiency.

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Authors and Affiliations

Z. Krawiecki
A. Cysewska-Sobusiak
G. Wiczynski
A. Odon
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Abstract

The article discusses the relationship between energy quality technologies cutting and their environmental friendliness. Based on the energy analysis shows that energy consumption in the individual technological process is connected with the cutting power and power loss, which form the environmental indicators of the cutting process and reduce its energy efficiency. In addition, it is shown that at implementation of technological processes on the equipment, electrical systems are AC systems the implementation of the cutting process occurs when excessive consumption of currents. The article presents the results of studies on the energy efficiency of cutting processes, definition of the complex influence of cutting processes on the environment and humans, the formation of ways of improving environmental and energy performance quality of these processes.

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Authors and Affiliations

Tadeusz Zaborowski
Leonid Shvartsburg
Natalja Ivanova
Sergej Ryabov
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Abstract

The paper proposes a study of molecular interactions using the planetary model of the atomic structure. The description refers to transfer of the interactions by electrons bonded with an atom in a planetary system. In molecules we refer to analysis of electrons that remain unpaired during the formation of chemical compounds. The planetary electronic state of molecular interactions is defined by considering the action arm for interatomic forces. Then the interaction torque is defined. The problem is studied in a collection of atoms forming a nanoparticle and then analysis is carried on in the entire volume of the nanocomposite, which is defined as a set of the nanoparticles in a field of matrix-nanofiller interactions. As a result, new mechanical, magnetic, and optical properties of the nanocomposite arise and are described herein. The atomic-scale phenomena are described by both classical and quantum mechanics and are then transferred to the nanoparticle scale by applying statistical mechanics. The quantum solutions for the optically active electrons form the basis for the optical properties of the nanocomposite using forced gyrobirefringence and Maxwell equations. The results of the theoretical analysis are confirmed by experiment using an electron paramagnetic resonance spectrometer.

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Authors and Affiliations

M. Sikoń
E. Bidzinska
J. Marcinowski
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Abstract

Neighbouring as a type of social interchange and multi-dimensional social phenomenon is of funda-mental importance in the social sciences and problems associated with intercultural and interethnic neighbouring are currently on the increase. Contemporary migration processes and ethnic diversity in Poland are relatively new issues that are reflected in the experiences of both migrants and representa-tives of the host society. The aim of this article is to analyse intercultural neighbourly contacts be-tween Poles and migrants in Warsaw in the context of Erving Goffman’s sociology of interaction. These contacts and the social processes they involve are of great importance when it comes to mi-grants’ integration in their new place of residence. The article considers how glances, gestures and behaviours are interpreted, leading to the formation of specific opinions and attitudes between mi-grants and Poles. Both ‘unfocused’ and ‘focused’ interactions are analysed, with an emphasis on ex-pectations and definitions of tactful behaviour in intercultural neighbourly encounters and the concept of ‘polite indifference.’ Conclusions are based on semi-structured interviews conducted with Poles and migrants from Vietnam, Turkey and African countries living in Warsaw, Poland.

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Authors and Affiliations

Aleksandra Winiarska
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Abstract

A study of the Quran makes it clear, that the New and Old Testament traditions are manifest in various forms in the sacred book of Muslims. This paper presents the phenomenon of these biblical borrowings, giving the references in the Quran to the biblical persons and main themes. One finds many of the Old and New Testament stories of the prophets sometimes in precise forms where the Quranic records are relative identical with the Biblical versions. On other fragments the Quranic narra- tives contain elements of Biblical traditions mixed with folklore and fables extracted from the Talmud and in some cases (such as the story of Abraham and the idols) the sources are entirely Midrashic-Haggadic or Apocryphal. It is worth to be pointed out that the influence of orthodox Christianity on the Quran was slight but apocryphal and heretical Christian legends are clearly visible in the various Quranic fragments. Probably it is a result of Muhammad’s journeys between Syria, Hijaz, and yemen.

Scholars have adopted a number of different theories explaining the phenomenon of the biblical borrowings found in the Quran. For example it is said about Muham- mad’s dependence upon Jewish teachers and thus an overarching Jewish influence on Islam. It is generally admitted that Muhammad had opportunity to come into contact with yemenite, Abyssinian, Ghassanite, and Syrian Christians, especially heretic.

Analyzes of the Quran in the light of parallel passages in the Bible, Talmud and Apocrypha permits us to formulate an idea that early Islamic revelations were com- pilation of Muhammad inspiration with repetition of information coming to his ears, some of it Biblical and true to history, the rest predominantly mythical and fictitious. This thesis is not accepted by Muslim scholars, who maintain that the Qur’an is the divine word of God without any interpolation.

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Authors and Affiliations

Ks. Krzysztof Kościelniak
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Abstract

In civil engineering, underground structures are exposed to various georisks and require greater attention and awareness of the need to identify them at the earliest possible stage of investment preparation and implementation. The assessment of the interaction of objects in the underground space is a task that requires the analysis of many influencing factors resulting from the geometry and characteristics of the constructed structure and existing buildings, in the context of soil and water conditions. The correctness of such an assessment and forecast of the range and scope of these impacts requires knowledge of both construction and geotechnical issues, as well as knowledge of using the experience gained, including the analysis of the results of observations and monitoring measurements. One of the main challenges associated with underground constructions is their impact on existing buildings and other structures adjacent to the developed site. As these structures are often highly susceptible to excavation-induced ground movements, their behavior have to be considered in a design as one of the geotechnical-related limit states. As in the analysis of limit states, various computational models can be used to assess the impact of investments, including analytical, semi-empirical or numerical models. In the process of assessing the impact of underground structures, it is also important to identify additional elements of potential georisks, e.g. the impact of accompanying works, which in certain situations may have a significant impact on the construction process, requiring preventive measures. On a few examples from the construction of deep excavations and tunnels in different soil and water conditions, the article discusses the aspects of the role of the accuracy of the identification of soil and water conditions and the creation of a reliable and useful subsoil model as elements allowing for the identification and minimization of georisks and its proper management.
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Authors and Affiliations

Tomasz Godlewski
1
ORCID: ORCID
Eugeniusz Koda
2
ORCID: ORCID
Monika Mitew-Czajewska
3
ORCID: ORCID
Stanisław Łukasik
1
ORCID: ORCID
Simon Rabarijoely
2
ORCID: ORCID

  1. Building Research Institute, 21 Ksawerów St., 02-656 Warsaw, Poland
  2. Institute of Civil Engineering, Warsaw University of Life Sciences – SGGW, 159 Nowoursynowska St., 02-776 Warsaw, Poland
  3. Warsaw University of Technology, Faculty of Civil Engineering, Al. Armii Ludowej 16, 00-637 Warsaw, Poland
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Abstract

The characteristics of the free gas jet, during its interaction with an upstream moving shock, were investigated experimentally. The initial strength of the shock remained constant and equal to M, = 1.34 whereas the Mach number of the free gas jet M, varied in a wide range of sub- and transonic values from M, = O up to M, = 1.4. It is shown that in the presence of the moving shock the jet characteristic becomes strongly modified. Outside the jet originates a cluster of pressure waves which moves upstream in jet surrounding. Spatial and frequency characteristics, as well as the number of pressure waves in the cluster, depend on the shock amplitude and the exit velocity of the free gas jet.
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Authors and Affiliations

Witold S. Selerowicz
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Abstract

Weak value amplification is a measurement technique where small quantum mechanical interactions are amplified and manifested macroscopically in the output of a measurement apparatus. It is shown here that the linear nature of weak value amplification provides a straightforward comparative methodology for using the value of a known small interaction to estimate the value of an unknown small interaction. The methodology is illustrated by applying it to quantify the unknown size of an optical Goos-Hänchen shift of a laser beam induced at a glass/gold interface using the known size of the shift at a glass/air interface.

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Authors and Affiliations

Allen D. Parks
Scott E. Spence
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Abstract

The present work deals with continuum mechanical considerations for deformable and rigid solids as well as for fluids. A common finite element framework is used to approximate all systems under considerations. In particular, we present a standard displacement based formulation for the deformable solids and make use of this framework for the transition of the solid to a rigid body in the limit of infinite stiffness. At last, we demonstrate how to immerse a discretized solid into a fluid for fluid-structure interaction problems.

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Authors and Affiliations

Christian Hesch
Peter Betsch
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Abstract

A novel type of an axial, piston-driven high pressure hydraulic pump with variable capacity marks a significant improvement in the area of the hydraulic machinery design. Total discharge from hydrostatic forces eliminates a need for a servomechanism, thus simplifying operation, reducing weight and introducing the possibility of the pump displacement control by computer. PWK-type pumps, invented in the Gdansk University of Technology, offer high efficiency for pressure levels up to 55 MPa, ability to work self sucking even at high speed. However, the heart of the new invention, the commutation unit, creates harmful pressure peaks. Those peaks can be mitigated by the introduction of a compensation chamber with elastic walls. Owing to the dynamic character of events taking place in the pump, a need for computer simulation arouse in order to understand phenomena leading to the occurrence of pressure peaks and choose compensation chamber parameters accordingly. A CFD package alone would not be sufficient to reliably represent the interaction between the compensation chamber wall and the working fluid. This paper presents Fluid Structure Interaction approach comparing 3 different models: 2 simplified models of the pump and a full pump model.

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Authors and Affiliations

Leszek Osiecki
Piotr Patrosz
Bettina Landvogt
Janusz Piechna
Tomasz Zawistowski
Bartek Żyliński
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Abstract

The category of expectation constitutes an important element of reflection in many scientific disciplines focusing on man. it is treated in both the categories of expectations inscribed in large social projects (e.g. of utopian nature) and individual expectations which build human daily routine. The article is divided into two parts. in the first, the issues of interpersonal expectations, analysed in the perspective of social psychology and sociology, will be undertaken. what will be explored here are the problems of defining the notion of expectation and the problems of expectations at school, which will be exemplified by the pygmalion effect. The first part is completed with some considerations on the meaning of expectation in sociology, the role of expectations in interaction, and the relations between expecting and social order.

In the second part, the author focuses on the issues of expectations inscribed in utopian projects (“great expectations”). pedagogical utopias and relations between utopias and popularization of normative (formal) or informal pedagogies are subjected to analysis. The author makes here some references to the concept of post-materialistic society, attempting to elicit relations between this type of society and popularization of nonformal pedagogies.

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Authors and Affiliations

Andrzej Kasperek
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Abstract

The focus point of this article is the territory of historical greenery (THG) of landscape architecture (LA) as a result of interaction between material environment design as applied art and society. As an object of applied art and anthropogenic activity, LA, as well as its research is an important area for natural, anthropogenic, social and economic sustainability. The study of THG problems today is based on the innate human right to live in a harmonious space of both aesthetic material and natural environment. Aesthetic quality criteria are important for understanding the systemic relationships between nature and human interaction embodied in LA as an applied art form. Therefore, the anthropogenic objects of LA and the spaces formed by them in the urban environment require studies of the material and natural environment and the anthropogenic functioning as a whole. Based on heuristic, qualitative and quantitative research methods and case studies, the article discusses the problems of interaction between present anthropogenic and natural processes, as well as the possible influence of such interactions on scenarios of LA development and future management of the territory of historical greenery.
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Authors and Affiliations

Jonas Jakaitis
1

  1. Vilnius Gediminas Technical University, Faculty of Architecture
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Abstract

In this paper, effects of non-Fourier thermal wave interactions in a thin film have been investigated. The non-Fourier, hyperbolic heat conduction equation is solved, using finite difference method with an implicit scheme. Calculations have been carried out for three geometrical configurations with various film thicknesses. The boundary condition of a symmetrical temperature step-change on both sides has been used. Time history for the temperature distribution for each investigated case is presented. Processes of thermal wave propagation, temperature peak build-up and reverse wave front creation have been described. It has been shown that (i) significant temperature overshoot can appear in the film subjected to symmetric thermal load (which can be potentially dangerous for reallife application), and (ii) effect of temperature amplification decreases with increased film thickness.

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Authors and Affiliations

Marcin Lenarczyk
Roman Domański

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