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Number of results: 19
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Abstract

An Internet application was developed to support the design process of the WLAN access network. The whole program was designed as a desktop application using the following languages: HTML, CSS and JavaScript. The main task of the application facilitates the planning process of the WLAN access network, including the location of multiple base stations. There is an example of using the program in the WLAN network planning process. The main purpose of this application as the ability to carry out network planning using multiple base stations and provide radio coverage for the entire area served by Wireless Internet Service Provider, is obtained.

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Authors and Affiliations

Sławomir Pluta
Jacek Pluta
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Abstract

The article presents a scientific research concerning the role and development of one of the most important leisure and recreation areas in Warsaw — Pole Mokotowskie, located near the city center, in three districts: Ochota, Śródmieście and Mokotów (part of the area is the Park of Józef Piłsudski). The research concentrates on determining the influence of contemporary spatial transformations of the park area on the spatial composition of the park.

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Authors and Affiliations

Katarzyna Pluta
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Abstract

Artykuł przedstawia badania dotyczące roli budowli sakralnych we współczesnym krajobrazie Warszawy. Obiekty sakralne powinny być częścią elementów i systemów tworzących tożsamość każdego miasta. Badania koncentrują się na określeniu roli budowli sakralnych w kompozycji krajobrazu miasta, w tym wpływu przekształceń przestrzennych terenów położonych w najbliższym sąsiedztwie budowli sakralnych na kompozycję przestrzenną badanych założeń.
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Authors and Affiliations

Katarzyna Pluta
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Abstract

The subject of the article is the design and practical implementation of the wireless mesh network. IQRF radio modules were used for the network design. The IQRF® technique has enabled the construction of a mesh network with the possibility of reconfiguration. The theoretical part contains a description of the IQRF® hardware solutions used. The practical scope includes the design part, where the configuration of the radio modules was carried out and the parameters of the radio network were set to allow its implementation in various topologies. Then, a wireless network consisting of 10 IQRF modules was launched in the P3 building of the Opole University of Technology. At this stage, configured radio modules were placed in selected rooms on all five floors of the building in order to carry out tests of the radio network constructed in this way. The tests included measuring the packet transmission delay time as well as the received signal strength. Research was carried out for several network topologies.

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Authors and Affiliations

Sławomir Pluta
Patryk Roszkowski
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Abstract

Currently used procedures in room acoustics measurements are not automated. Particularly in medium-sized and large areas they require a lot of time and intensive labour which directly translates into an increase in the measurement cost. Introduction of an automated system would increase efficiency of the measurements, and therefore could present both practical and scientific benefit. The paper presents initial feasibility study for designing a system that permits the measurement of selected acoustic parameters for any choice of three-dimensional grid of measurement points throughout the volume of the room. The system will utilize an autonomous probe attached to a blimp, and will be able to measure and analyze acoustic characteristics of the rooms. The article discusses the initial choices of the system elements, starting from the general idea, through the mechanical design and control procedures, the software that controls positioning and flying of the probe, up to the automation of the measurement procedure and its possible impact on the acoustic field.
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Authors and Affiliations

Bartłomiej Borkowski
Marek Pluta
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Abstract

In this article, an analysis of an innovative system for filtering signals in the audible range (16 Hz - 20 kHz) on programmable logic devices using a filters with a finite impulse response, is presented. Mentioned system was neat combination of software and hardware platform, where in the program layer a multiple programming languages including VHDL, JavaScript, Matlab or HTML were used to create completely useful application. To determine the coefficients of polynomial filters the Matlab Filter Design & Analysis Tool was used. Thanks to the developed graphic layer, a user-friendly interface was created, which allows easily transfer the required coefficients from the computer to the executive system. The practical implementation made on the FPGA platform, specifically on the Altera DE2- 115 development kit with the FPGA Cyclone IV, was compared with simulation realization of Matlab FIR filters. The performed research confirm the effectiveness of filtration in real time with up to 128th order of the filter for both audio channels simultaneously in FPGA-based system.
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Authors and Affiliations

Adrian Lipowski
1
Paweł Majewski
1
Sławomir Pluta
1

  1. Opole University Technology, Opole, Poland
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Abstract

Telomeres are repetitive sequence structures at the ends of chromosomes. They consist of the double stranded DNA repeats followed by the short single stranded DNA. In humans and other verterbrates the telomeric sequence is composed of tandem of TTAGGG repeats. With each cells division telomeres shorten by up to 200 base pairs. Telomerase is an enzyme responsible for continuous cell growth and is repressed in most somatic cells, except proliferating progenitor cells, but in more than 85% of cancer cells telomerase expression is observed. Tumour cells with metastatic potential may demonstrate a high telomerase activity, allowing cells to escape from the inhibition of cell proliferation due to shortened telomeres. Determination of telomerase expres- sion was performed with the use of PCR ELISA in samples isolated from bovine leukaemia virus (BLV) infected cows. Telomerase activity was found in almost all investigated samples. The relative telomerase activity (RTA) was higher in infected cows than in healthy animals and the differences were statistically significant (α=0.05). In blood lymphocytes of BLV-infected cows the mean values of telomerase expression determined in real-time PCR were 3534.12 copies, in the healthy group there were 1010.10 copies and these differences were also statistically significant. For telomere length evaluation the Telomere PNA/FITC FISH and Telomere PNA/FITC FISH for flow cytometry were used. The mean fluorescence intensity of telomere sequences calculated on the surface of interphase nuclei of leukaemic blood lymphocytes was lower than that in the control animals and the difference was statistically significant. The mean length of telomeres in BLV- infected and healthy cows was 31.63 ± 12.62 and 38.4 ± 4.03, (p=0.112), respectively.

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Authors and Affiliations

M. Szczotka
J. Kocki
E. Iwan
A. Pluta
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Abstract

Dendritic cells (DCs) due to their ability to present antigens are essential during the immune response to infections. The aim of the study was to evaluate the influence of bovine leukaemia virus (BLV) infection on DC properties. Cytokine profiles of myeloid, plasmacytoid and mono- cyte derived DCs from BLV infected cattle were analysed. Concentrations of IL-6, IL-10, IL-12, IFN-γ, and TNF-α in DC cultures were measured by flow cytometry. Obtained results indicated activation of pDCs population, where a significant increase in production of the IFN-γ was shown. Meanwhile, a decrease in production of IFN-γ and increase in production of IL-10 were shown in mDCs; the main population responsible for antigens presentation. This may indicate a contribu- tory role of the population during the process of persistent infection. In MoDCs population a significant elevation in secretion of proinflammatory cytokines – IL-6 and TNF-α was noted.

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Authors and Affiliations

E. Iwan
M. Szczotka
J. Kocki
A. Pluta
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Abstract

Electric guitar manufacturers have used tropical woods in guitar production for decades claiming it as beneficiary to the quality of the instruments. These claims have often been questioned by guitarists but now, with many voices raising concerns regarding the ecological sustainability of such practices, the topic becomes even more important. Efforts to find alternatives must begin with a greater understanding of how tonewood affects the timbre of an electric guitar. The presented study examined how the sound of a simplified electric guitar changes with the use of various wood species. Multiple sounds were recorded using a specially designed test setup and their analysis showed differences in both spectral envelope and the generated signal level. The differences between the acoustic characteristics of tones produced by the tonewood samples explored in the study were larger than the just noticeable differences reported for the respective characteristics in the literature. To verify these findings an informal listening test was conducted which showed that sounds produced with different tonewoods were distinguishable to the average listener.
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Bibliography

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Authors and Affiliations

Jan Jasiński
1
Stanisław Oleś
1
Daniel Tokarczyk
1
Marek Pluta
1

  1. Department of Mechanics and Vibroacoustics, AGH University of Science and Technology, Cracow, Poland
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Abstract

Local service centre, defined as multi-functional public space providing access to everyday services, promoting social integration and building local identity, is an essential hub in the urban service sector. From the public policy perspective appropriate location and furnishing of local service centres is a basic condition for shaping territorial cohesion. This paper synthesises the to-date knowledge on mechanisms determining the development of service sector in cities, including new phenomena such as decentralisation of urban functions, urban shrinkage, remote services provision or commercialisation of lifestyle. Critical literature review enables the confrontation of various research perspectives and leads to distinguishing key factors affecting the development of urban local service centres in the first half of 21st century and defining the current challenges for public policy.

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Authors and Affiliations

Łukasz Damurski
Jerzy Ładysz
Jacek Pluta
Wawrzyniec Zipser
Magdalena Mayer-Wydra

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