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Number of results: 95
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Abstract

The existence of extensive records for the impact of night sky brightness on the animals’ behavior in their natural environment shows the need to investigate the level of artificially induced night sky glow (light pollution) in the protected areas.

The results of multi-night sky brightness measurements carried out at the selected sites in Polish mountain areas under various atmospheric conditions are presented. Conducted measurements show a strong impact of the artificial sky glow on the night sky brightness, which is the essence of light pollution. The influence of both distant urban centers, as well as local tourist resorts on the size of studied phenomenon in the mountain areas, which causes both ecological and touristic degradation of these areas was stated. In a few studied areas the level of night sky brightness greatly exceeds the natural one and is comparable to such levels measured inside the cities. It was found that only the southern part of the Polish Carpathians can be considered an area free of light pollution.

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Authors and Affiliations

Wiesław Kaszowski
Tomasz Ściężor
Marek Kubala
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Abstract

This work concerns measurements of the radiant intensity emitted by LEDs. The influence of selected factors and parameters on the final measurement result are discussed. The research was conducted using two type of detectors: light meter and CCD camera, to compare the degree of influence of these parameters depending on the measurement instrument used.

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Authors and Affiliations

Joanna Parzych
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Abstract

In 2020, an international project on residential lighting started and was implemented in four countries (Poland, Sweden, UK and Turkey). This article presents the results of a survey carried out in Poland, in the winter term between November 2020 and January 2021. A total of 125 Polish residents (59 women, 65 men, one person did not wish to specify gender) participated in the survey. A variety of data was collected on the respondents and their assessments as well as on their satisfaction with day- and artificial lighting in residential living spaces. The results from questionnaires were analyzed with STATISTICA 13.3. Descriptive statistics and Spearman rank order correlations were adopted to identify the light-related aspects, lighting patterns, and respondents’ perception of day- and artificial lighting conditions in living areas. The results revealed that satisfaction with daylighting in the living area, both in summer and winter, was significantly correlated with daylighting level, daylighting uniformity, sunlight exposure and view-out. The results also revealed that satisfaction with artificial lighting was significantly correlated with artificial lighting level, artificial lighting uniformity and color rendering. The results provide valuable information on lighting and factors that influence the luminous environment in residential living spaces.
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Authors and Affiliations

Piotr Pracki
1
ORCID: ORCID
Rengin Aslanoglu
2
Jan K. Kazak
2
ORCID: ORCID
Begüm Ulusoy
3
Sepideh Yekanialibeiglou
4

  1. Warsaw University of Technology, Electrical Power Engineering Institute, Division of Lighting Technology, Warsaw, Poland
  2. Wrocław University of Environmental and Life Sciences, Institute of Spatial Management, Wrocław, Poland
  3. University of Lincoln, Interior Architecture and Design, School of Design, Lincoln, UK
  4. Bilkent University, Department of Interior Architecture and Environmental Design, Faculty of Art, Design and Architecture, Ankara, Turkey
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Abstract

Light-weight Self-Compacting Concrete (LWSCC) might be the answer to the increasing construction requirements of slenderer and more heavily reinforced structural elements. However there are limited studies to prove its ability in real construction projects. In conjunction with the traditional methods, artificial intelligent based modeling methods have been applied to simulate the non-linear and complex behavior of concrete in the recent years. Twenty one laboratory experimental investigations on the mechanical properties of LWSCC; published in recent 12 years have been analyzed in this study. The collected information is used to investigate the relationship between compressive strength, elasticity modulus and splitting tensile strength in LWSCC. Analytically proposed model in ANFIS is verified by multi factor linear regression analysis. Comparing the estimated results, ANFIS analysis gives more compatible results and is preferred to estimate the properties of LWSCC.

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Authors and Affiliations

B. Vakhshouri
S. Nejadi
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Abstract

A thermal resistance characterization of semiconductor quantum-well heterolasers in the AlGaInAs-AlGaAs system (λst ≈ 0.8 μm), GaSb-based laser diodes (λst ≈ 2 μm), and power GaN light-emitting diodes (visible spectral region) was performed. The characterization consists in investigations of transient electrical processes in the diode sources under heating by direct current. The time dependence of the heating temperature of the active region of a source ΔT(t), calculated from direct bias change, is analyzed using a thermal RTCT equivalent circuit (the Foster and Cauer models), where RT is the thermal resistance and CT is the heat capacity of the source elements and external heat sink. By the developed method, thermal resistances of internal elements of the heterolasers and light-emitting diodes are determined. The dominant contribution of a die attach layer to the internal thermal resistance of both heterolaser sources and light-emitting diodes is observed. Based on the performed thermal characterization, the dependence of the optical power efficiency on current for the laser diodes is determined.

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Authors and Affiliations

Yurii Bumai
Aleh Vaskou
Valerii Kononenko
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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

Lighting technologies developed significantly in the last decade. New LED light sources, dedicated luminaires and improved lighting control techniques gave rise to new possibilities in improving energy efficiency of lighting solutions. The article is an overview of interior, road and exterior architectural object lighting design strategies. It also presents design considerations that directly impact lighting conditions and energy efficiency. Practical examples of the application of basic design strategies, accompanied by the obtained energy results, are also depicted. Issues discussed in the article may be useful in researching and designing interior and road lighting, as well as floodlighting. They can also be useful in planning and implementing strategies aimed at improving lighting conditions and energy efficiency of lighting solutions.

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Authors and Affiliations

P. Pracki
A. Wiśniewski
D. Czyżewski
R. Krupiński
K. Skarżyński
M. Wesołowski
A. Czaplicki
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Abstract

Directionality of light and modelling effects impact lighting quality in interiors. The modelling effects depend on luminaires’ photometric characteristics and their layout but also on interior size and reflectance. The objective of this research was to evaluate lighting design limitations and impact of interior and luminaires’ characteristics on the modelling effects, as well as elaborate a prediction method of the modelling effects in interior lighting. The General Index of Modelling was used for the analysis of the modelling effects in interiors. The implementation of the research objectives was based on the simulation and statistical analysis. 432 situations, varied interior size and reflectance, lighting class, luminaire downward luminous intensity distribution and layout were considered. The results show that achieving the required range of the General Index of Modelling in interior lighting is substantially limited. Luminaires’ layout impacts the General Index of Modelling the most. The elaborated multiple linear regression models can have a practical use for interior lighting design and analysis in terms of obtaining therequired range of the General Index of Modelling.
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Authors and Affiliations

Piotr Pracki
ORCID: ORCID
Paulina Komorzycka
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Abstract

The article presents how multi-layered urban lighting projects fit into the programs of integrated activities to improve the living conditions of the local community, the surrounding space, and its economic relations. The role of the electric lighting in revealing the night image of the city, its promotion and public spaces transformations offering new impressions to city residents is growing thanks to the use of the SSL technology. The authors focus on a role of outdoor lighting projects in urban regeneration within the selected urban areas. The paper describes how conscious shaping of lighting by analysing the goals and stages of the project can contribute to the improvement of quality in the processes of renewal of degraded urban areas.

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Authors and Affiliations

Natalia Sokół
Katarzyna Rusek
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Abstract

General lighting is the most common way of illuminating interiors and the source of electricity consumption in buildings. This fact forces the search for lighting solutions effective both for people and the environment. In this study the impact of room and luminaire characteristics on general lighting conditions and energy efficiency in interiors is considered. In rooms of different sizes and reflectances, seventeen luminaire types with various light distributions were arranged in uniform layouts. The levels of average illuminance, uniformity and normalised power density related to two horizontal working planes were calculated. The impact of working plane reduction, room index and reflectances, lighting class and luminous intensity distribution of luminaire on the considered parameters was investigated. The use of the reduced working plane resulted in the increase in the average illuminance (7.7% on average), uniformity (33% on average) and normalised power density (23% on average). The impact of the room index and lighting class on the average illuminance and normalised power density was significant while the impact of the luminaire luminous intensity distribution and room reflectances was low. The normalised power density levels of the general electric lighting in interiors, with luminaire luminous efficacy of 100 lm/W, are in the following range: 1.08‒3.42 W/m² per 100 lx. Based on these results a normalised power density level of 2 W/m² per 100 lx is recommended for designing and assessing the new general electric lighting systems in buildings.

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Authors and Affiliations

P. Pracki
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Abstract

The β phase (Al 12Mg 17) precipitated by heat treatment in some alloy compositions may result deterioration of corrosion resistance. However, much of its role remains unclear. The effect of the β phase on the corrosion resistance behavior in a NaCl solution was presented in this study. The specimen was Mg-9mass%Al (AM90) alloy and the content of the β phase precipitant was controlled systematically by aging time at 473 K. Area rate of β and lamellar phase in the specimens were 0, 10 and 100%, respectively. According to the results of cathodic polarization curves measurement, the corrosion current density of α phase was 0.215 A/m2 and β phase of it was 0.096 A/m2. While, the specimen includes 10% of β and lamellar phase showed large corrosion current density of 0.251 A/m2. Positive correlation between the β phase and the open circuit potential, suggest that the β phase acts as a cathodic electrode. Moreover, the microstructure after postentiostatic corrosion tests was also support the role of β phase.
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Authors and Affiliations

Masahiko Hatakeyama
1
ORCID: ORCID
Yusuke Shimada
2
ORCID: ORCID
Naoki Kawate
2
ORCID: ORCID
Kaede Sarayama
2
ORCID: ORCID
Satoshi Sunada
1
ORCID: ORCID

  1. University of Toyama, Graduate School of Materials Science and Engineering for Research, 3190 Gofuku, Toyama 930-8555, Japan
  2. University of Toyama, Graduate School of Materials Science and Engineering for Education, Japan
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Abstract

The article raised issues related to the design and execution of low-energy objects in Polish conditions. Based on the designed single-family house, adapted to the requirements of the National Fund for Environmental Protection and Water Management ("NF40" standard), the tools to assist investment decisions by investors were shown. An economic analysis and a multi-criteria analysis were performed using AHP method which had provided an answer to the question whether it is worthwhile to bear higher investment costs in order to adjust to the standards of energy-efficient buildings that fulfil a minimal energy consumption's requirements contained in Polish law. In addition, the variant of object that had optimal characteristics due to the different preferences of investors was indicated. This paper includes analysis and observations on the attempts to unify that part of the building sector, which so far is considered to be personalized, and objects in accordance with the corresponding idea are designed as "custom-made".

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Authors and Affiliations

K. Tomczak
O. Kinash
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Abstract

The effect of emulsifier volume on emulsion system stability of plant origin being the basis of diet supplements for animals in winter season was analyzed. For this purpose, measurements of the backscattered light intensity as the function of the measuring cell height were conducted with a Turbiscan LAB optical analyzer. System stability was analyzed on the basis of Turbiscan Stability Index values. A Helos laser analyzer and a Nikon Eclipse E400 POL optical microscope were used to investigate drop size distribution and analyze microscopic pictures. It was shown that emulsion with 10% (w/w) of the emulsifier was the most stable one.

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Authors and Affiliations

Anna Zalewska
Joanna Kowalik
Ireneusz Grubecki
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Abstract

We introduce numerical methods and algorithms to estimate the main parameters of fractal-like particle aggregates from their optical structure factor (i.e. light scattering diagrams). The first algorithm is based on a direct and simple method, but its applicability is limited to aggregates with large size parameter and intermediate fractal dimension. The second algorithm requires to build calibration curves based on accurate particle agglomeration and particle light scattering models. It allows analyzing the optical structure factor of much smaller aggregates, regardless of their fractal dimension and the size of the single particles. Therefore, this algorithm as well as the introduction of a criterial curve to detect the different scattering regimes, are thought to be powerful tools to perform reliable and reproducible analysis.

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Authors and Affiliations

Janusz Mroczka
Mariusz Woźniak
Fabrice R.A. Onofri
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Abstract

The results of surface texture measurements obtained with the stylus equipment, white light interferometer

and confocal profilometer of the same samples were compared. Machined isotropic and anisotropic surfaces,

of symmetric and asymmetric ordinate distribution were measured. Forms were removed using polynomials.

Sampling intervals and measuring areas during computations of parameters were the same. Discrepancies

between the results obtained with various methods were observed and discussed. It was found that errors of

surface texture measurement with the optical methods depend on the type of surface topography.

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Authors and Affiliations

Paweł Pawlus
Rafał Reizer
Michał Wieczorowski
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Abstract

The paper presents a new method of surface topology reconstruction from a white light interferogram. The method is based on interferogram modelling by complex exponents (Prony method). The compatibility of white light interferogram and Prony models has already been proven. Effectiveness of the method was tested by modelling and examining reconstruction of tilted and spherical surfaces, and by estimating the reconstruction accuracy.
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Authors and Affiliations

Anna Khoma
Jarosław Zygarlicki
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Abstract

BC (Black Carbon), which can be found in the atmosphere, is characterized by a large value of the imaginary part of the complex refractive index and, therefore, might have an impact on the global warming effect. To study the interaction of BC with light often computer simulations are used. One of the methods, which are capable of performing light scattering simulations by any shape, is DDA (Discrete Dipole Approximation). In this work its accuracy was estimated in respect to BC structures using the latest stable version of the ADDA (vr. 1.2) algorithm. As the reference algorithm the GMM (Generalized Multiparticle Mie-Solution) code was used. The study shows that the number of volume elements (dipoles) is the main parameter that defines the quality of results. However, they can be improved by a proper polarizability expression. The most accurate, and least time consuming, simulations were observed for IGT_SO. When an aggregate consists of particles composed of ca. 750 volume elements (dipoles), the averaged relative extinction error should not exceed ca. 4.5%.
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Authors and Affiliations

Krzysztof Skorupski
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Abstract

The paper presents the authors’ concept of an adaptive road lighting that is concurrent with vehicles moving on roads. The lighting system is based on luminaires with light emitting diodes. The authors describe the operation of the adaptive road lighting system and point out benefits and limitations of the solution. The theoretical considerations are supported by an analysis of the installed and working system that was implemented at Bożeny street in Poznan, Poland. The system was also evaluated by the residents living near the street.

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Authors and Affiliations

S. Zalewski
P. Pracki
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Abstract

In the paper, on the basis of the performed tests, low-cycle fatigue characteristics (LCF) of selected light metal alloys used among others in the automotive and aviation industries were developed. The material for the research consisted of hot-worked rods made of magnesium alloy EN-MAMgAl3Zn1, two-phase titanium alloy Ti6Al4V and aluminium alloy AlCu4MgSi(A). Alloys used in components of means of transport should have satisfactory fatigue, including low-cycle fatigue, characteristics. Low-cycle fatigue tests were performed on an MTS-810 machine at room temperature. Low-cycle fatigue tests were performed for three total strain ranges Δεt = 0.8%, 1.0% and 1.2% with a cycle asymmetry coefficient R = –1. On the basis of the obtained results, characteristics of the fatigue life of materials, cyclic deformation σa = f(N) and cyclic deformation of the tested alloys were developed. The tests showed that titanium alloy Ti6Al4V was characterised by the highest fatigue life Nf, whereas the lowest fatigue life was found in the tests of the aluminium alloy AlCu4MgSi(A).

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Authors and Affiliations

G. Junak
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Abstract

This paper is focused on the manufacturing and properties of light weight aggregates made from local waste materials. The waste materials were car windshield glass contaminated by PVB foil, fly ash, mine slates as well as wastes after toothpaste production. The main aim of the research was to combine car windshield glass and the aluminosilicate coal mine slates as a basis for light weight aggregates manufacturing. Fly ash were added in order to modify rheological properties of the plastic mass. Toothpaste wastes were introduced as a source of carbonates and CO2 evolution during thermal treatment. After milling and mixing all materials they were pressed and sintered at temperature range of 950°C-1100°C in air. The results show that it is possible to receive light weight aggregates only from the Silesian local waste materials. The significant influence of sintering temperature on properties of aggregates was observed.

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Authors and Affiliations

J. Smoleń
T. Pawlik
M. Sopicka-Lizer
D. Michalik
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Abstract

A complete system of a Laser Radar is described in this paper. One explains the principles of the laser and all additional devices used in this system in order to obtain a compact and eye-safe system. The principle and realization of algorithms for controlling the cruise and speed of the vehicle are described. By applying modal control, and choosing the optimal mode for reducing the speed, one derives the system equation and determines its coefficients. Finally, the paper presents simulations of the laser scanning system, the modal control system and the behavior of the system affected by different errors and disturbances. The effects of instrumental errors are defined and simulation is performed illustrating how such a control system is influenced by internal and external disturbances.

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Authors and Affiliations

Alexander Zbrutsky
Maryam Kaveshgar
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Abstract

Light exposure is an important environmental factor which breaks seed dormancy in many plant species. Phytochromes have been identified as playing a crucial role in perception of the light signal that releases seed germination in Arabidopsis. Phototropins (Phot1, Phot2) are blue/UV-photoreceptors in plants which mediate phototropic responses, chloroplast relocation, hypocotyl growth inhibition and stomata opening. We studied germination under different light conditions in Arabidopsis Phot1-null and Phot2-null mutants and in a double phot1phot2 mutant. Germination of single phot1 and phot2 mutants in darkness was much lower than in wildtype (WT) seeds, whereas double phot1phot2 mutant lacking both functional phototropins germinated at frequency comparable to WT seeds, irrespective of light and temperature conditions. Light treatment of imbibed seeds was essential for effective germination of phot1, irrespective of low-temperature conditioning. In contrast, cold stratification promoted dark germination of phot2 seeds after imbibition in dim light. Low germination frequency of phot1 seeds under low light intensity suggests that the presence of functional Phot1 might be crucial for effective germination at these conditions. The lower germination frequency of phot2 seeds under continuous light suggests that Phot2 might be responsible for stimulating germination of seeds exposed to direct daylight. Thus, the phototropin system may cooperate with phytochromes regulating the germination competence of seeds under different environmental conditions

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Authors and Affiliations

Paweł Jedynak
Przemysław Malec
Beata Myśliwa-Kurdziel
Elżbieta Turek

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