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Number of results: 29
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Abstract

Mikołaj Łabowski, Professor Emeritus at the Institute of Acoustics, Adam Mickiewicz University in Poznań, passed away on the 8th of October, 2013. Professor Mikołaj Łabowski was born on the 17th of December, 1935, in Florynka in the southern part of Poland. He graduated from the Faculty of Mathematics, Physics and Chemistry of the Adam Mickiewicz University receiving his Master of Science degree in physics in 1962. Eight years later he obtained his PhD title from the same university. In 1981, on the basis of the book “Ultra- and hypersonic properties of selected liquids and critical mixtures” he obtained the degree of habilitated doctor. The President of Poland awarded him the titles of Associate Professor in Physics in the year 1991 and Full Professor in 1999. From 1985 to 1987,Mikołaj Łabowski held the post of Vice-Dean for Students’ Affairs at the Faculty of Mathematics and Physics of the AdamMickiewicz University. In the years 1996–1999, he was the Director of the University’s Institute of Acoustics. He held many posts in the Polish Acoustical Society, of which he was a HonoraryMember. He always served with advice and assistance in scientific matters to the Committee of Acoustics of the Polish Academy of Sciences. Professor Łabowski was an outstanding scientist, one of the founders of ultrasonic physics in Poland. After returning from scholarship in the Lomonsov University in Moscow, he became an expert in the field of ultrasonic studies of liquids and liquid mixtures. His groundbreaking works on ultrasonic properties of critical binary mixtures opened up new perspectives in the research of dynamic phenomena in the vicinity of critical temperatures. Professor Łabowski’s outstanding scientific achievements were recognized by rewarding him the Minister of Education Prize in the years 1981 and 1987. Throughout his whole professional career associated with the Adam Mickiewicz University in Poznań, Professor Łabowski has published over 100 papers, mostly in renowned international scientific journals, and carried out an intensive teaching activity. Through his profound knowledge and enthusiasm, Professor Mikołaj Łabowski continuously inspired colleagues and collaborators and decisively shaped the development of ultrasonic physics in Poznań. With the death of Professor Mikołaj Łabowski, Polish acoustics has lost a great researcher, teacher, and scholar.
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Authors and Affiliations

Tomasz Hornowski
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Abstract

In this paper we have studied the driftless control system on a Lie group which arises due to the invariance of Black-Scholes equation by conformal transformations. These type of studies are possible as Black-Scholes equation can be mapped to one dimensional free Schrödinger equation. In particular we have studied the controllability, optimal control of the resulting dynamics as well as stability aspects of this system.We have also found out the trajectories of the states of the system through two unconventional integrators along with conventional Runge-Kutta integrator.

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Authors and Affiliations

Archana Tiwari
Debanjana Bhattacharyya
K.C. Pati
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Abstract

Biometrics provide an alternative to passwords and pins for authentication. The emergence of machine learning algorithms provides an easy and economical solution to authentication problems. The phases of speaker verification protocol are training, enrollment of speakers and evaluation of unknown voice. In this paper, we addressed text independent speaker verification using Siamese convolutional network. Siamese networks are twin networks with shared weights. Feature space can be learnt easily by training these networks even if similar observations are placed in proximity. Extracted features from Siamese then can be classified using difference or correlation measures. We have implemented a customized scoring scheme that utilizes Siamese’ capability of applying distance measures with the convolutional learning. Experiments made on cross language audios of multi-lingual speakers confirm the capability of our architecture to handle gender, age and language independent speaker verification. Moreover, our designed Siamese network, SpeakerNet, provided better results than the existing speaker verification approaches by decreasing the equal error rate to 0.02.

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Authors and Affiliations

Hafsa Habib
Huma Tauseef
Muhammad Abuzar Fahiem
Saima Farhan
Ghousia Usman
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Abstract

In this paper, a modified sound quality evaluation (SQE) model is developed based on combination of an optimized artificial neural network (ANN) and the wavelet packet transform (WPT). The presented SQE model is a signal processing technique, which can be implemented in current microphones for predicting the sound quality. The proposed method extracts objective psychoacoustic metrics including loudness, sharpness, roughness, and tonality from sound samples, by using a special selection of multi-level nodes of the WPT combined with a trained ANN. The model is optimized using the particle swarm optimization (PSO) and the back propagation (BP) algorithms. The obtained results reveal that the proposed model shows the lowest mean square error and the highest correlation with human perception while it has the lowest computational cost compared to those of the other models and software.

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Authors and Affiliations

Mehdi Pourseiedrezaei
Ali Loghmani
Mehdi Keshmiri

Authors and Affiliations

Agnieszka Ozga
1
Jacek Wierzbicki
1
Dominik Mleczko
1

  1. Faculty of Mechanical Engineering and Robotics, Department of Mechanics and Vibroacoustics, AGH University of Krakow, Kraków, Poland
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Abstract

This study aims to determine the potential of Kebar grass extract in reducing the impact of liver damage in mice offspring ( Mus musculus) from parent exposed to carbofuran during lactation period. 42 lactation mice ( Mus musculus) used in the study were divided into seven groups, each group consisting of six mice. Carbofuran, Kebar grass extract, and vitamin C are administered orally on days 1 to 14 after birth. This group consisted of K (aquadest), P1 (carbofuran 1/4 LD50 0.0125 mg/day), P2 (carbofuran 1/8 LD50 0.00625 mg/day), P3 (Kebar grass extract 3.375 mg (0.2 ml) + carbofuran 1/4 LD50), P4 (Kebar grass extract 3.375 mg (0.2 ml) + carbofuran 1/8 LD50), P5 (vitamin C 5 mg (0.2 ml) + carbofuran 1/4 LD50), and P6 (vitamin C 5 mg (0.2 ml) + carbofuran 1/8 LD50). On the 15th day after birth, mice were sacrified and their liver taken for microscopic examination with hematoxilin and eosin staining. The scoring data were analyzed using Kruskal-Wallis and Mann-Whitney test. The result showed significant different (p<0.05) among the treatment groups. Mean of P4 in degeration is (1.13), necrosis (1.13) and inflamation (0.73), while the mean of P6 in degeneration is (2.20), necrosis (2.73) and inflamation (1.93). The conclusion of this research is giving Kebar grass extract is more effective in reducing degeneration, necrosis and inflammatory cell’s infiltration than vitamin C in in mice offspring ( Mus musculus) from parent exposed to carbofuran during lactation period.
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Bibliography


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Chandra D, Tripathi UN, Srivastava S, Amit Swaroop A (2011) Carbofuran induced biochemical toxicity in mice; Protective role of Momor-dica charantia. Eur J Exp Biol 1: 106-112.

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Gbadegesin MA, Owumi SE, Akinseye V, Odunola OA (2013) Evaluation of hepatotoxicity and clastogenicity of carbofuran in male Wistar rats. Food Chem Toxicol 5: 115-119.

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Gupta RC (1994) Carbofuran Toxicity. J Toxicol Environ Health 43: 383-418.

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Keegan J, Whelan M, Danaher M, Crooks S, Sayers R, Anastasio A, Elliott C, Brandon D, Furey A, O’Kennedy R (2009) Bensimidazole carbamate residues in milk: Detection by Surface Plasmon Resonance-biosensor, using a modified QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) method for extraction. Anal Chim Acta 654: 111-119.

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Trisetiyono Y, Pramono N, Hidayat ST, Widjiati (2019) The differences of malondialdehyde serum level, expression of tumor necrosis factor alpha and vascular endothelial growth factor, and the area of endometriotic implants in administration of Kebar grass extract (Biophytum peter-sianum) and green tea extract (Camelia sinensis) to mice. Trad Med J 24: 169-177.

Unitly AJA, Inara C (2011) Potential of kebar grass (Biophytum Petersianum Klotzsch) in improving reproductive performance. Proceedings of the National Seminar Universitas Patimura, Ambon, Indonesia, pp 329-333.
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Authors and Affiliations

N.A. Yulitasari
1
S. Hidanah
1
Widjiati
1
V.F. Hendrawan
2
E.M. Luqman
1

  1. Department of Veterinary Science Faculty of Veterinary Medicine Universitas Airlangga Kampus C Unair, Jalan Mulyorejo Surabaya 60115 Indonesia
  2. Department of Animal Reproduction Faculty of Veterinary Medicine, Universitas Brawijaya, Jl. MT. Haryono No.169, Ketawanggede, Lowokwaru, Kota Malang, 65144 Indonesia
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Abstract

The development of in vitro embryo production (IVEP) techniques in Felis catus is a fitting model with potential application to the conservation of endangered felid species. To improve the quality of IVEP techniques an appropriate balance of pro- and antioxidants should be provided. Under in vitro conditions, high levels of superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT) mRNA provide a defence mechanism against oxidative stress for embryos. In order to improve the development of cat oocytes, the effects of SOD and CAT supplemented to in vitro maturation (IVM) medium and of GPx supplemented to in vitro fertilization (IVF) medium on development and embryo production in vitro were evaluated. Data showed an increase of 70 and 77 % of cleaved embryo and blastocyst formation, respectively, in the experiment with SOD and CAT addition to IVM medium; in the experiment with GPx addition to IVF medium the number of cleaved embryos doubled and the number of embryos increased by 96 %. Therefore, our results were positive and encourage us to continue studies on cat oocytes evaluating the effects of various dosages and combination of antioxidants.

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Authors and Affiliations

N. Cocchia
S. Tafuri
C. Del Prete
V. Palumbo
L. Esposito
L. Avallone
F. Ciani
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Abstract

During the Brexit campaign, both those who opted for Britain leaving the EU and those who wanted to remain in the structures of the Union referred to William Shakespeare to support the rightness of their preference. The question of how Shakespeare would have voted was raised by numerous journalists, writers and politicians who either tried to present Shakespeare as a national bard promoting British isolationism or a staunch adherent of England being an integral part of the European continent. The paper scrutinizes some aspects of Shakespeare’s plays which indicate the writer’s attitude towards the relations between England and Europe.

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Authors and Affiliations

Paweł Kaptur
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Abstract

Thermal spraying methods are commonly used to regenerate damaged surface or change materials surface properties. One of the newest methods is cold spraying, where coating is deposited of material in the solid state. Therefore shape and size of the powder particles are very important parameters. The article presents the influence of copper powder morphology on mechanical properties of the coatings (adhesion, hardness, Young’s modulus) deposited with the Low Pressure Cold Spraying method on the AA1350 aluminium alloy substrate. The coatings were deposited using two commercially available copper powders with spherical and dendritic morphology and granulation of –40+10 µm. The bond strength of coatings was determined with the pull off method, the hardness with the Vickers method at load of 2.94 N, while the Young’s modulus through measurement of nanoindentation. Microstructure of the coatings was analysed using the light and scanning electron microscopy (SEM). Shape of the powder influences mechanical properties of the coating significantly. The coatings deposited with dendritic powder had low mechanical properties, hardness of the 81 HV0.3 order and adhesion of about 4 MPa. However changing powder morphology to spherical increased hardness of the coating to 180 HV0.3 and adhesion to 38.5 MPa.
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Authors and Affiliations

D. Grygier
1
ORCID: ORCID
M. Rutkowska-Gorczyca
1
ORCID: ORCID
M.G. Winnicki
2
ORCID: ORCID
T. Wojdat
2
ORCID: ORCID

  1. Wroclaw University of Science and Technology, Faculty of Mechanical Engineering, Department of Vehicle Engineering, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland
  2. Wroclaw University of Science and Technology, Faculty of Mechanical Engineering, Department of Metal Forming, Welding and Metrology, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland
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Abstract

The article presents an analysis of the impact of bending optical fibers with tilted Bragg gratings on their spectral parameters. This article proves that it is possible to a choose TFBG cladding mode and the optical spectrum range related to it that allows the best metrological properties to be obtained when measuring bend. The results contained in the paper explain why the minima in the spectral characteristics, corresponding only to some cladding modes, change their shape during TFBG bending, which is important for application of Bragg gratings as bending sensors. It has been presented that in the case of TFBG we are able to aggregate the knowledge obtained during experiment to the form of a physical model of the fiber bending sensor.
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Authors and Affiliations

Piotr Kisała
1

  1. Lublin University of Technology, Nadbystrzycka 38A, 20-618 Lublin, Poland
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Abstract

In this research work, the Ti-6Al-4V material was used for the investigation of machining parameters by means of hybrid micro electrical discharge machining to improve the machining process and reduce the negative effects of debris accumulation in the drilled hole. L9 orthogonal array was used in the Taguchi based grey relational analysis to optimize the parameters such as material removal rate and diametrical accuracy of the machining process for Ti-6Al-4V. This work encompasses the design, development, and calibration of the work piece vibration platform and experimental analysis of the process parameters by means of the hybrid micro electrical discharge machining process. The maximum material removal rate and minimum surface roughness was observed at the current value of 2.5 A, pulse on time is 2 µs and pulse off time is 14.5 µs. The maximum material removal rate was observed for the increase in pulse on time with 14.4  µs and 4 A current level. The diametrical accuracy of the microholes was increased while increasing the pulse off time and decreasing the pulse on time. The fluid flow simulation has been conducted to find out the pressure drop and to know the velocity of the flow inside the hole for the effective flushing of the debris during machining.

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Authors and Affiliations

T. Mugilan
M.S. Aezhisai Vallavi
S. Santhosh
D. Sugumar
S. Christopher Ezhil Singh
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Abstract

The article presents the tender procedure used to select the best – according to the investor’s requirements – variant of the offer for the General Contractor of a development investment. The subject of the contract was the comprehensive construction of a complex of single-family, semi-detached buildings with a traditional brick structure. In the opinion of the authors of the article, a well-thought-out selection of an appropriate contractor is one of the most important elements of the investment process, because it has a direct impact on the fluency of the construction stage and the future use of the investment, during the warranty period. In addition, a diligently conducted tender procedure allows to minimize the risk of selecting an unprofessional contractor and thus allows to counteract many possible problems and conflicts during the implementation of the subject of the contract. At the stage of the tender procedure, four variants of offers for the comprehensive implementation of the construction of a complex of single-family semi-detached buildings of the following criteria: price (C1), lead time (C2), form of payment (C3), liquidity (C4), experience (C5) and resources (C6). In this article, the authors presented in details the calculation procedure using the ideal point method. Conducting a multi-criteria assessment of variants, based on the selected methods, also clearly verified the strengths and weaknesses of all tenderers, enabling the selection of the best one in the light of the adopted assessment criteria.
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Authors and Affiliations

Mariola Książek-Nowak
1
ORCID: ORCID
Marek Ozimek
2

  1. Warsaw University of Technology, Faculty of Civil Engineering, Al. Armii Ludowej 16, 00-637 Warsaw, Poland
  2. Kiloutou Polska Sp. z. o. o., ul. Rokicinska 142 Z, 92-412 Łódz, Poland
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Abstract

Numerous European countries experience a steady increase in the share of electric (EV) and hybrid electric (HEV) vehicles in the traffic stream. These vehicles, often referred to as low- or zero-emission vehicles, significantly reduce air pollution in the road environment. They also have a positive effect on noise levels in city centers and in the surroundings of low-speed roads. Nevertheless, issues related to modeling noise from electric and hybrid vehicles in the outdoor environment are still not fully explored, especially in the rural road settings. The article attempts to assess the degree of noise reduction around these roads based on different percentages of EVs in the traffic stream. Input data for noise modeling was obtained from 133 sections of homogeneous rural roads in Poland. Based on their analysis, it was first determined on how many of these road sections electric-vehicle-induced noise reduction would be possible, taking into account the traffic speeds occurring on them. Next, a computational algorithm that can be used to calculate noise reduction in the CNOSSOS-EU model is presented, and noise modeling is performed based on it for different percentages of electric vehicles in the traffic stream.
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Authors and Affiliations

Maciej Hałucha
1
ORCID: ORCID
Janusz Bohatkiewicz
2
ORCID: ORCID
Piotr Mioduszewski
3
ORCID: ORCID

  1. EKKOM Sp. z o.o., ul. dr Józefa Babinskiego 71B, 30-394 Cracow, Poland
  2. Tadeusz Kosciuszko Cracow University of Technology, Faculty of Civil Engineering, ul. Warszawska 24, 31-155 Cracow, Poland
  3. Gdansk University of Technology, Faculty of Mechanical Engineering and Ship Technology, ul. Gabriela Narutowicza 11/12, 80-233 Gdansk, Poland
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Abstract

This paper presents probabilistic assessment of load-bearing capacity and reliability for different STM of beams loaded with a torsional and bending moment. Three beams having different reinforcement arrangement obtained on the basis of STM but the same overall geometry and loading pattern were analysed. Stochastic modelling of this beams were performed in order to assess probabilistic load-bearing capacity. In the analysis, the random character of input data - concrete and steel was assumed. During the randomization of variables the Monte Carlo simulation with the reduce the number of simulations the Latin Hypercube Sampling (LHS) method was applied. The use of simulation methods allows for approximation of implicit response functions for complex in description and non-linear reinforced concrete structures. On the basis of the analyses and examples presented in the paper, it has been shown that the adoption of different ST models determines the different reliability of the analysed systems and elements.

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Authors and Affiliations

Lidia Buda-Ożóg
ORCID: ORCID
Katarzyna Sieńkowska
ORCID: ORCID
Izabela Skrzypczak
ORCID: ORCID
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Abstract

The main idea of this article is the necessity to take into account the multi-variant technological and organizational solutions of individual construction works in order to ensure rational planning for the implementation of construction projects. In practice, selection of construction works most often limited to the evaluation of technological and organizational solutions on the basis of time and cost criteria. However, it should be remembered that construction projects usually have a complex technological and organizational structure. This fact may increase the durations and costs of individual works in relation to their planned durations and costs. Therefore, the authors propose to take into account the criterion of technological and organizational complexity of the assessed construction work. The article describes the procedure for the technological and organizational optimization of construction works. A numerical example of the method of selecting technological and organizational solutions with the use of a fuzzy relation of preferences is also presented. The article also proposes to combine the computational selection model with the network planning model in a graphic form. This approach expands the computational and decision-making possibilities of network models in the practice of planning construction projects.
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Authors and Affiliations

Nabi Ibadov
1
ORCID: ORCID
Sahib Farzaliyev
2
ORCID: ORCID
Irene Ladnykh
1
ORCID: ORCID

  1. Warsaw University of Technology, Faculty of Civil Engineering, Al. Armii Ludowej 16, 00-637 Warsaw, Poland
  2. Azerbaijan University of Architecture and Construction, Faculty of Construction, Ayna Sultanova 11, Baku, Azerbaijan
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Abstract

In order to obtain the change rule of surrounding rock structure displacement and supporting structure internal force with time during the construction of the low mountain ridge tunnel, this paper relies on the Xishan Tunnel Project as the background. During tunneling, the displacement around the tunnel, the subsidence of the surface, the internal force of the steel arch and the pressure between the two layers of support are monitored dynamically. According to the above monitoring and measurement data, and the monitoring data analysis and nonlinear regression fitting, the predicted trend curve is obtained, the displacement change rules and characteristics of various surrounding rocks of the tunnel are obtained, to ensure the construction safety and stability requirements of supporting structure, and to provide a reasonable opportunity for the construction of secondary lining.
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Authors and Affiliations

Jian Ouyang
1
ORCID: ORCID
Haijun Wang
1
ORCID: ORCID
Luxiang Wu
1
ORCID: ORCID
Kexin Zhang
2
ORCID: ORCID
Xingwei Xue
2
ORCID: ORCID

  1. Engineering Department, Guangzhou Expressway Co., LTD, China
  2. School of Transportation and Surveying Engineering, Shenyang Jianzhu University, China
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Abstract

The constrained averaged controllability of linear one-dimensional heat equation defined on R and R+ is studied. The control is carried out by means of the time-dependent intensity of a heat source located at an uncertain interval of the corresponding domain, the end-points of which are considered as uniformly distributed random variables. Employing the Green’s function approach, it is shown that the heat equation is not constrained averaged controllable neither in R nor in R+. Sufficient conditions on initial and terminal data for the averaged exact and approximate controllabilities are obtained. However, constrained averaged controllability of the heat equation is established in the case of point heat source, the location of which is considered as a uniformly distributed random variable. Moreover, it is obtained that the lack of averaged controllability occurs for random variables with arbitrary symmetric density function.

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Authors and Affiliations

Jerzy Klamka
Asatur Zh. Khurshudyan
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Abstract

The technical requirements for the determination of physical parameters of vibration isolating material have not been standardized in Europe and Poland yet, which significantly hinders the ability to compare vibration isolating materials offered on the market. Therefore, there is a need for establishing a norm that could be applied both for the determination of the physico-mechanical properties of elastic vibration isolation elements in rail transport for domestic and foreign producers as well as in their selection for application in a specific vibration isolation system. The paper presents a proposal to standardize the methodology of the estimation of vibration isolation materials physical parameters authorized for use in vibration isolation systems used in rail transport. Methodology for measuring the physico-mechanical parameters of vibration isolating material presented in the paper forms uniform test procedure developed based on a fragmentary norms for flexible materials testing. The use of the proposed research methodology enables the creation of a unified database of elastic materials which parameters will be easy to compare, and choice between them will become easier for designers of vibration isolation systems used in rail transport.

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Authors and Affiliations

Jarosław Bednarz
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Abstract

The knowledge about membrane contactors is growing rapidly but is still insufficient for a reliable designing. This paper presents a new type of membrane contactors that are integrated with one of the following ways of separation by using absorbents, micelles, flocculants, functionalized polymers, molecular imprints, or other methods that are based on aggregation. The article discusses methods for designing multi-stage cascade, usually counter-current. At every stage of this cascade, relevant aggregates are retained by the membrane, while the permeate passes freely through membrane. The process takes place in the membrane boundary layer with a local cross-flow of the permeate and the retentate. So the whole system can be called a cross-counter-current. The process kinetics, k, must be coordinated with the permeate flux, J, and the rate of surface renewal of the sorbent on the membrane surface, s. This can be done by using ordinary back-flushing or relevant hydrodynamic method of sweeping, such as: turbulences, shear stresses or lifting forces. A surface renewal model has been applied to adjust the optimal process conditions to sorbent kinetics. The experimental results confirmed the correctness of the model and its suitability for design of the new type of contactors.

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Authors and Affiliations

Andrzej B. Kołtuniewicz
Szymon Modelski
Anna Witek
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Abstract

The electrical power drawn by an induction motor is distorted in case of appearance of a certain type of failures. Under spectral analysis of the instantaneous power one obtains the components which are connected with definite types of damage. An analysis of the amplitudes and frequencies of the components allows to recognize the type of fault.

The paper presents a metrological analysis of the measurement system used for diagnosis of induction motor bearings, based on the analysis of the instantaneous power. This system was implemented as a set of devices with dedicated software installed on a PC. A number of measurements for uncertainty estimation was carried out. The results of the measurements are presented in the paper. The results of the aforementioned analysis helped to determine the measurement uncertainty which can be expected during bearing diagnostic measurements, by the method relying on measurement and analysis of the instantaneous power of an induction machine.

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Authors and Affiliations

Ariel Dzwonkowski
Leon Swędrowski
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Abstract

Sapelovirus A (SV-A) is a positive-sense single-stranded RNA virus which is associated with acute diarrhea, pneumonia and reproductive disorders. The virus capsid is composed of four proteins, and the functions of the structural proteins are unclear. In this study, we expressed SV-A structural protein VP1 and studied its antigenicity and immunogenicity. SDS-PAGE analysis revealed that the target gene was expressed at high levels at 0.6 mM concentration of IPTG for 24 h. The mouse polyclonal antibody against SV-A VP1 protein was produced and reached a high antiserum titer (1: 2,048,000). Immunized mice sera with the recombinant SV-A VP1 protein showed specific recognition of purified VP1 protein by western blot assay and could recognize native SV-A VP1 protein in PK-15 cells infected with SV-A by indirect immunofluorescence assay. The successfully purified recombinant protein was able to preserve its antigenic determinants and the generated mouse anti-SV-A VP1 antibodies could recognize native SV-A, which may have the potential to be used to detect SV-A infection in pigs.

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Authors and Affiliations

T.T. Zhao
L. Cui
L. Chen
J.J. Li
Q.L. Liang
P.J. Wu
X.Q. Yu
Z.H. Zhang
X.G. Hua

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