Search results

Filters

  • Journals
  • Authors
  • Keywords
  • Date
  • Type

Search results

Number of results: 6
items per page: 25 50 75
Sort by:
Download PDF Download RIS Download Bibtex

Abstract

Water scarcity is a phenomenon that is occurring more and more frequently in larger areas of Europe. As a result of drought, there are significant drops in yields. As demand for food continues to rise, it is becoming necessary to bring about a substantial increase in crop production. The best solution to water scarcity appears to be irrigation for crops that are particularly sensitive to drought. Today, many technical solutions are used to supply and distribute water to crops. The optimal solution is drip irrigation, which makes it possible to deliver water directly to the plant root system to save melting freshwater resources. In the article special attention was paid to methods of supplying electricity to power irrigation pumps. The analysis was made for areas with a significant distance between the agricultural land and the urbanised area (which has water and electricity). The authors have selected the parameters of an off-grid photovoltaic mini-hydropower plant with energy storage (with a power of 1.36 kW). An analysis was made of the profitability of such an investment and a comparison with other types of power supply. Based on the performed calculations, a prototype power supply system equipped with photovoltaic panels was made to show the real performance of the proposed system. The tests carried out showed that the irrigation pump will be powered most of the time with a voltage whose parameters will be very close to the nominal ones.
Go to article

Authors and Affiliations

Zbigniew Skibko
1
ORCID: ORCID
Wacław Romaniuk
2
ORCID: ORCID
Andrzej Borusiewicz
3
ORCID: ORCID
Stanisław Derehajło
3
ORCID: ORCID

  1. Bialystok University of Technology, Faculty of Electrical Engineering, Wiejska 45 D, 15-351 Białystok, Poland
  2. Institute of Technology and Life Sciences – National Research Insitute, Falenty, Poland
  3. The Higher School of Agribusiness in Łomża, Poland
Download PDF Download RIS Download Bibtex

Abstract

The most popular field methods of measurements of raised marine beach altitudes used by geomorphologists are presented. Compared data from clisimeter routes, altimeter routes and from readings from a photogeological map and directly from air photos compose the profiles. Advantages and disavantages of each method are discussed.

Go to article

Authors and Affiliations

Jerzy Nitychoruk
Wojciech Ozimkowski
Ryszard Szczęsny
Download PDF Download RIS Download Bibtex

Abstract

Properties of excitons confined to potential fluctuations due to indium distribution in the wetting layer which accompany self-assembled InAs/GaAs quantum dots are reviewed. Spectroscopic studies are summarized including time-resolved photoluminescence and corresponding single-photon emission correlation measurements. The identification of charge states of excitons is presented which is based on results of a theoretical analysis of interactions between the involved carriers. The effect of the dots’ environment on their optical spectra is also shown.

Go to article

Authors and Affiliations

A. Babiński
Download PDF Download RIS Download Bibtex

Abstract

The impulse noise is agent harmful to health not only in the case of shots from firearms and the explosions of explosive materials. This kind of noise is also present in many workplaces in the industry. The paper presents the results of noise parameters measurements in workplaces where four different die forging hammers were used. The measured values of the C-weighted peak sound pressure level, the A-weighted maximum sound pressure level and A-weighted noise exposure level normalized to an 8 h working day (daily noise exposure level) exceeded the exposure limit values. For example, the highest measured value of the C-weighted peak sound pressure level was 148.9 dB. In this study possibility of the protection of hearing with the use of earplugs or earmuffs was assessed. The measurement method for the measurements of noise parameters under hearing protection devices using an acoustical test fixture instead of testing with the participation of subjects was used. The results of these measurements allows for assessment which of two tested earplugs and two tested earmuffs sufficiently protect hearing of workers in workplaces where forging hammers are used.

Go to article

Authors and Affiliations

Emil Kozłowski
Rafał Młyński
Jan Adamczyk
Download PDF Download RIS Download Bibtex

Abstract

The acoustic properties of the sitar string are studied with the aid of a physical model. The nonlinearity of the string movement caused by the bridge acting as an obstacle to the vibrating string is of special interest. Comparison of the model's audio output to recordings of the instrument shows interesting similarities. The effects dispersion and bridge have on the sound of the instrument are demonstrated in the model.

Go to article

Authors and Affiliations

Sadjad Siddiq
Download PDF Download RIS Download Bibtex

Abstract

In 2009 Pentor Research International, acting on behalf of the Museum of the 2nd World War in Gdańsk, organized impressive research into the knowledge and memory of the war in Poland. The comprehensive results are published in the book Między codziennością a wielką historią (Between everydayness and monumental history) by Piotr T. Kwiatkowski and others (Warsaw, Gdańsk 2010). The author of the present article comments on this research. He is mostly astonished by the regional differences in memory of the war in a country like present day Poland that is relatively homogenous. He proposes differentiating between what he calls „a stable memory” and a „momentaneous memory”. The latter appears strong but in fact it depends on what the TV says the last week before the research is done.
Go to article

Authors and Affiliations

Marcin Kula
ORCID: ORCID

This page uses 'cookies'. Learn more