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Light Pollution of the Mountain Areas in Poland / Zanieczyszczenie Świetlne W Obszarach Górskich W Polsce

Wiesław Kaszowski Tomasz Ściężor Marek Kubala
Archives of Environmental Protection | 2012 | vol. 38 | No 4 | DOI: 10.2478/v10265-012-0042-4
Keywords Light pollution artificial sky glow light-island light sources illumination
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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

Analysis of lighting on exterior scaffoldings at different times of day

Iwona Szer Jacek Szer
Archives of Civil Engineering | 2022 | vol. 68 | No 3 | 139-154 | DOI: 10.24425/ace.2022.141878
Keywords construction sites workers illuminance lighting uniformity scaffoldings
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Abstract

Lighting of the workplaces has a large impact on safety, proper vision comfort and visual efficiency. The aim of this article is to present an analysis of the lighting of the workplaces of people working on scaffoldings. The researches were carried out on 23 frame-type facade scaffoldings. The scaffoldings were examined from March to October 2017. Due to the specificity of works performed on scaffoldings, the researches were carried out in accordance with an individually adapted research program. The study analyzed the illuminance at particular points and variability in the lighting uniformity in a given workspace. Analysis of the obtained results showed a large variability in illuminance in workplaces of people working on scaffoldings. The measured illuminance levels in the workspaces on the one hand were higher than the minimum illuminance levels defined by the construction site standards, but on the other hand, illuminance levels that may dazzle the employees were also recorded. The luminous intensity depended on the season, time of day, location of the scaffolding, as well as the presence of a protective net installed on the scaffolding, which reduced the occurrence of values that could lead to situations in which the worker could be dazzled. The protective net installed on the scaffolding also reduces the differences in lighting in the scaffolding workspace, improving the lighting conditions of the workplaces.
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Authors and Affiliations

Iwona Szer
1
ORCID: ORCID
Jacek Szer
1
ORCID: ORCID
  1. Lodz University of Technology, Department of Building Materials Physics and Sustainable Design, Politechniki 6, 90-924 Łódz, Poland

Small lighting luminaires for illumination applications

Antoni Różowicz Henryk Wachta Sebastian Różowicz
Archives of Electrical Engineering | 2022 | vol. 71 | No 4 | 1035-1050 | DOI: 10.24425/aee.2022.142123
Keywords computer visualization illumination LED light sources luminance distribution
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Abstract

The application of solid-state light sources in luminaires creates a new quality in illumination design works. In a confrontation with a commonly used but relatively unattractive flood method, the use of small-size luminaires allows one to present an illuminated architectural object in a more attractive way in the evening and at night. In this case, it is possible to apply the principles of illumination described in the literature, especially the principle of height amplification and the principle of depth amplification. The conceptual work of illumination with the use of a large number of small-size luminaires does not require the use of supporting graphical tools, but the specification of actual lighting equipment using only polygonal samples in this case is not possible. The paper presents selected issues of the key stages of the completed work. Using specialized computer software, a geometric model of the architectural object has been developed, facade materials have been parameterized, models of small-size illuminating equipment have been selected and, finally, calculations of luminance distribution on illuminated surfaces have been carried out. As a result of computer work, luminance distributions and photorealistic visualizations of illuminations from defined main directions of observation were obtained. The Lubomirski Palace in Przemysl is an example of the architectural object indicated for detailed works.
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Authors and Affiliations

Antoni Różowicz
1
ORCID: ORCID
Henryk Wachta
2
Sebastian Różowicz
1
ORCID: ORCID
  1. Department of Industrial Electrical Engineering and Automatic Control, Kielce University of Technology, Tysiaclecia Panstwa Polskiego 7, 25-314 Kielce, Poland
  2. Department of Power Electronics and Power Engineering, Rzeszow University of Technology, Wincentego Pola 2, 35-959 Rzeszow, Poland

Investigation of noise in surface topography measurement using structured illumination microscopy

Zhen Li Sophie Gröger
Metrology and Measurement Systems | 2021 | vol. 28 | No 4 | 767-779 | DOI: 10.24425/mms.2021.137706
Keywords surface topography measurement measurement noise uncertainty structured illumination microscopy
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Abstract

Noise is a fundamental metrological characteristic of the instrument in surface topography measurement. Therefore, measurement noise should be thoroughly studied in practical measurement to understand instrument performance and optimize measurement strategy. This paper investigates the measurement noise at different measurement settings using structured illumination microscopy. The investigation shows that the measurement noise may scatter significantly among different measurement settings. Eliminating sample tilt, selecting low vertical scanning interval and high exposure time is helpful to reduce the measurement noise. In order to estimate the influence of noise on the measurement, an approach based on metrological characteristics is proposed. The paper provides a practical guide to understanding measurement noise in a wide range of applications.
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Bibliography

[1] International Organization for Standardization. (2019). Geometrical product specifications (GPS) – Surface texture: Areal – Part 600: Metrological characteristics for areal topography measuring methods (ISO 25178-600:2019). https://www.iso.org/standard/67651.html
[2] de Groot, P., & DiSciacca, J. (2020). Definition and evaluation of topography measurement noise in optical instruments. Optical Engineering, 59(6), 064110. https://doi.org/10.1117/1.OE.59.6.064110
[3] Eifler, M., Hering, J., Seewig, J., Leach, R. K., von Freymann, G., Hu, X., & Dai, G. (2020). Comparison of material measures for areal surface topography measuring instrument calibration. Surface Topography: Metrology and Properties, 8(2), 025019. https://doi.org/10.1088/2051-672X/ab92ae
[4] Vanrusselt, M., Haitjema, H., Leach, R., & de Groot, P. (2021). International comparison of noise in areal surface topography measurements. Surface Topography: Metrology and Properties, 9(2), 025015. https://doi.org/10.1088/2051-672X/abfa29
[5] Giusca, C. L., Leach, R. K., Helary, F., Gutauskas, T., & Nimishakavi, L. (2012). Calibration of the scales of areal surface topography-measuring instruments: Part 1. Measurement noise and residual flatness. Measurement Science and Technology, 23(3), 035008. https://doi.org/10.1088/0957-0233/23/3/035008
[6] Grochalski, K., Wieczorowski, M., Pawlus, P., & H’Roura, J. (2020). Thermal sources of errors in surface texture imaging. Materials, 13(10), 2337. https://doi.org/10.3390/ma13102337
[7] Fu, S., Cheng, F., Tjahjowidodo, T., Zhou, Y., & Butler, D. (2018). A non-contact measuring system for in-situ surface characterization based on laser confocal microscopy. Sensors, 18(8), 2657. https://doi.org/10.3390/s18082657
[8] Barker, A., Syam, W. P., & Leach, R. K. (2016, October). Measurement noise of a coherence scanning interferometer in an industrial environment. Proceedings of the Thirty-First Annual Meeting of the American Society for Precision Engineering (vol. 65, pp. 594–599). http://eprints.nottingham.ac.uk/id/eprint/38454
[9] Gomez, C., Su, R., De Groot, P., & Leach, R. (2020). Noise reduction in coherence scanning interferometry for surface topography measurement. Nanomanufacturing and Metrology, 3, 68–76. https://doi.org/10.1007/s41871-020-00057-4
[10] Leach, R. (Ed.). (2011). Optical Measurement of Surface Topography (Vol. 8). Springer Berlin Heidelberg. https://doi.org/10.1007/978-3-642-12012-1
[11] Maculotti, G., Feng, X., Galetto, M., & Leach, R. (2018). Noise evaluation of a point autofocus surface topography measuring instrument. Measurement Science and Technology, 29(6), 065008. https://doi.org/10.1088/1361-6501/aab528
[12] De Groot, P. J. (2017). The meaning and measure of vertical resolution in optical surface topography measurement. Applied Sciences, 7(1), 54. https://doi.org/10.3390/app7010054
[13] Haitjema, H., & Morel, M. A. A. (2005). Noise bias removal in profile measurements. Measurement, 38(1), 21–29. https://doi.org/10.1016/j.measurement.2005.02.002
[14] Leach, R., Haitjema, H., Su, R.,&Thompson, A. (2020). Metrological characteristics for the calibration of surface topography measuring instruments: a review. Measurement Science and Technology, 32(3), 032001. https://doi.org/10.1088/1361-6501/abb54f
[15] DIN. (2008). Optical measurement and microtopographies – Calibration of interference microscopes and depth measurement standards for roughness measurement (VDI/VDE 2655 Blatt 1.1).
[16] DIN. (2010). Optical measurement of microtopography – Calibration of confocal microscopes and depth setting standards for roughness measurement (VDI/VDE 2655 Blatt 1.2).
[17] de Groot, P., & DiSciacca, J. (2018, August). Surface-height measurement noise in interference microscopy. Interferometry XIX (Vol. 10749, p. 107490Q). International Society for Optics and Photonics. https://doi.org/10.1117/12.2323900
[18] Pawlus, P., Reizer, R., & Wieczorowski, M. (2017). Problem of non-measured points in surface texture measurements. Metrology and Measurement Systems, 24(3), 525–536. https://doi.org/10.1515/mms-2017-0046
[19] International Organization for Standardization. (2012). Geometrical product specifications (GPS) – Surface texture: Areal – Part 3: Specification operators (ISO 25178-3:2012).
[20] Blateyron, F. (2014, May). Good practices for the use of areal filters. Proc. 3rd Seminar on Surface Metrology of the Americas.
[21] Podulka, P. (2020). Proposal of frequency-based decomposition approach for minimization of errors in surface texture parameter calculation. Surface and Interface Analysis, 52(12), 882–889. https://doi.org/10.1002/sia.6840
[22] He, B., Zheng, H., Ding, S.,Yang, R.,& Shi, Z. (2021).Areviewof digital filtering in surface roughness evaluation. Metrology and Measurement Systems, 28(2). https://doi.org/10.24425/mms.2021.136606
[23] Podulka, P. (2020). Comparisons of envelope morphological filtering methods and various regular algorithms for surface texture analysis. Metrology and Measurement Systems, 27(2), 243–263. https://doi.org/10.24425/mms.2020.132772
[24] Podulka, P. (2021). Reduction of Influence of the High-Frequency Noise on the Results of Surface Topography Measurements. Materials, 14(2), 333. https://doi.org/10.3390/ma14020333
[25] Todhunter, L., Leach, R., & Blateyron, F. (2020). Mathematical approach to the validation of surface texture filtration software. Surface Topography: Metrology and Properties, 8(4), 045017. https://doi.org/10.1088/2051-672X/abc0fb
[26] Vanrusselt, M., & Haitjema, H. (2020). Reduction of noise bias in 2.5 D surface measurements. In Proceedings of Euspen’s 20th International Conference & Exhbition, 277–281. European Society for Precision Engineering; Nothampton.
[27] Gomez, C., Su, R., Lawes, S., & Leach, R. (2019). Comparison of two noise reduction methods in coherence scanning interferometry for surface measurement. The 14th International Symposium on Measurement Technology and Intelligent Instruments.
[28] Sánchez, Á. R., Thompson, A., Körner, L., Brierley, N., & Leach, R. (2020). Review of the influence of noise in X-ray computed tomography measurement uncertainty. Precision Engineering, 66, 382–391. https://doi.org/10.1016/j.precisioneng.2020.08.004
[29] confovis GmbH. Structured Illumination Microscopy. https://www.confovis.com/en/optical-measurement
[30] International Organization for Standardization. (2012). Geometrical product specifications (GPS) – Surface texture: Areal – Part 2: Terms, definitions and surface texture parameters (ISO 25178-2:2012).
[31] International Organization for Standardization. (2020). Geometrical product specifications (GPS) – Surface texture: Areal – Part 700: Calibration, adjustment and verification of areal topography measuring instruments (ISO/DIS 25178-700:2020).
[32] Leach, R., Haitjema, H., & Giusca, C. (2019). A metrological characteristics approach to uncertainty in surface metrology. Optical Inspection of Microsystems, 73–91. CRC Press.
[33] Haitjema, H. (2015). Uncertainty in measurement of surface topography. Surface Topography: Metrology and Properties, 3(3), 035004. https://doi.org/10.1088/2051-672X/3/3/035004
[34] Yang, Z., Kessel, A., & Häusler, G. (2015). Better 3D Inspection with Structured Illumination: Signal Formation and Precision. Applied Optics, 54(22), 6652–6660. https://doi.org/10.1364/AO.54.006652
[35] Gomez, C., Su, R., Thompson, A., DiSciacca, J., Lawes, S., & Leach, R. K. (2017). Optimization of surface measurement for metal additive manufacturing using coherence scanning interferometry. Optical Engineering, 56(11), 111714. https://doi.org/10.1117/1.OE.56.11.111714
[36] Zhou, Y., Troutman, J., Evans, C., & Davies, A. (2014, June). Using the random ball test to calibrate slope dependent errors in optical profilometry. Optical Fabrication and Testing, OW4B-2. Optical Society of America. https://doi.org/10.1364/OFT.2014.OW4B.2
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Authors and Affiliations

Zhen Li
1
ORCID: ORCID
Sophie Gröger
1
  1. Chemnitz University of Technology, Department of Production Measuring Technology, Reichenhainer Straße 70, 09126 Chemnitz, Germany

Experimental study of non-measured points on surface measurement using structured illumination microscopy

Zhen Li Sophie Gröger
Metrology and Measurement Systems | 2022 | vol. 29 | No 4 | 763-778 | DOI: 10.24425/mms.2022.143071
Keywords non-measured points structured illumination microscopy areal surface texture parameters measurement uncertainty
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Abstract

Non-measured points (NMPs) are one of vital problems in optical measurement. The number and location of NMPs affect the obtained surface texture parameters. Therefore, systematic studying of the NMP is meaningful in understanding the instrument performance and optimizing measurement strategies. This paper investigates the influence of measurement settings on the non-measured points ratio (NMPR) using structured illumination microscopy. It is found that using a low magnification lens, high exposure time, high dynamic range (HDR) lighting levels, and low vertical scanning interval may help reduce the NMPR. In addition, an improved approach is proposed to analyze the influence of NMP on areal surface texture parameters. The analysis indicates that the influence of NMP on some parameters cannot be ignored, especially for extreme height parameters and feature parameters.
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Authors and Affiliations

Zhen Li
1
ORCID: ORCID
Sophie Gröger
1
  1. Chemnitz University of Technology, Department of Production Measuring Technology, Reichenhainer Straße 70, 09126 Chemnitz, Germany

Analysis of impact of atmospheric attenuation and measurement uncertainties on laser hazard distances in navigable airspace for visible cw laser radiation

Jarosław Młyńczak
Metrology and Measurement Systems | 2023 | vol. 30 | No 2 | 259-272 | DOI: 10.24425/mms.2023.144869
Keywords aviation safety laser hazard distances in navigable airspace laser safety laser hazard distance laser illumination
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Abstract

This document provides a simplified solution to the problem of calculation of laser hazard distances defined in the Advisory Circular 70-1B by the U.S. Federal Aviation Administration regarding atmospheric attenuation (assuming its constant value) and measurement uncertainties. The calculation approaches and examples presented in this document do not specify the procedure that should be followed in the case of atmospheric attenuation, nor do they take into account the uncertainties associated with the measured parameters. The analysis presented in the article complements to some extent AC 70-1B and can be used by those who need such a simplified solution regarding illumination of landing or taking off aircrafts. The article presents a sample analysis for a typical laser pointer, where the necessary parameters of the laser beam along with the appropriate uncertainties were determined in accordance with the methods accredited by the Polish Centre for Accreditation while the appropriate laser hazard distances were calculated taking into account different atmospheric attenuation coefficients.
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Authors and Affiliations

Jarosław Młyńczak
1
  1. Military University of Technology, Institute of Optoelectronics, Gen. S. Kaliskiego 2, 00-908 Warszawa, Poland

Characterization of GaN nanostructures by electron field and photo-field emission

V. Litovchenko A. Evtukh A. Grygoriev
Opto-Electronics Review | 2017 | vol. 25 | No 3 | 251-262
Keywords GaN nanostructures Electron field emission Photo-field emission Electron redistribution Illumination Quantum effects
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Abstract

The electron field and photo-field emission from GaN nanostructures has been analyzed in this review. In order to explain the obtained experimental results, a model was proposed taking into account the change in carrier concentration distribution in the main and the satellite valley during the emission process. The lowering of work function (due to the increased number of carriers in the satellite valley) can explain the decrease in the Fowler-Nordheim plot slope. It was shown that the energy difference between the main and satellite valley in GaN was decreased in the case of quantum confinement, thus increasing the probability of electron transition from Γ to X valley at same electric fields.

Investigations of electron photo-field emission demonstrated that the Fowler–Nordheim plots of the emission current have different slopes for nonilluminated and illuminated devices. A model based on the electron emission from valleys having different specific electron affinities is proposed to explain the experimental results. In the absence of illumination the emission takes place only from the lower valley. Upon UV illumination and presence of a high electric field at the emitter tip, the upper valley of the conduction band appears to be occupied by electrons generated at the valence band.

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Authors and Affiliations

V. Litovchenko
A. Evtukh
A. Grygoriev

Power loss mechanisms in small area monolithic-interconnected photovoltaic modules

R. Kimovec H. Helmers A.W. Bett M. Topič
Opto-Electronics Review | 2018 | vol. 26 | No 2 | 158-164
Keywords Monolithic interconnected photovoltaic module Laser power converter Optical and electrical losses Current mismatch Gaussian illumination
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Abstract

Power loss mechanisms in small area monolithic-interconnected photovoltaic modules (MIM) are described and evaluated. Optical and electrical losses are quantified and individual loss components are derived for loss mechanisms of small area radial (radius = 1 mm) pie-shaped six-segment GaAs MIM laser power converter. At low monochromatic homogeneous illumination (Glow = 1.8 W/cm2, λ0 = 809 nm) conversion efficiency of the cell, designed for a low irradiance, is reduced by 3.7%abs. due to isolation trench optical losses and by 7.0%abs. due to electrical losses (mainly perimeter recombination). Electrical losses in a device designed for a high irradiance, result in 18%abs. decrease of output power under homogeneous monochromatic illumination (Ghigh = 83.1 W/cm2, λ0 = 809 nm), while 11.6%abs. losses are attributed to optical reasons. Regardless the irradiance level, optical losses further increase if the device is illuminated with a Gaussian instead of an ideal flattop beam profile. In this case, beam spillage losses occur and losses due to isolation trenches and reflections from metallization are elevated. On top of that, additional current mismatch losses occur, if individual MIM’s segments are not equally illuminated. For the studied device, a 29 μm off center misalignment of a Gaussian shaped beam (with 1% spillage) reduces the short circuit current Isc by 10%abs. due to the current mismatch between segments.

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Authors and Affiliations

R. Kimovec
H. Helmers
A.W. Bett
M. Topič

Research on the output characteristics of photovoltaic arrays under partial shading conditions based on peak point approximate calculation method

Liming Wei KaiKai Li
Archives of Electrical Engineering | 2022 | vol. 71 | No 2 | 409-424 | DOI: 10.24425/aee.2022.140719
Keywords I-V characteristic equation peak point approximate calculation method peak voltage point shadow occlusion’s rate type of illumination distribution
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Abstract

The mismatch effect of photovoltaic (PV) arrays due to different illumination intensity has a significant impact on the output characteristics and output power of PV arrays, which is crucial to understand the output characteristics of PV arrays and optimize the array configuration in order to improve the value of the maximum power point. This paper illustrates the short-circuit current mismatch of series circuits, and the open-circuit voltage mismatch of parallel circuits and proposes corresponding solutions for each mismatch phenomenon. The output characteristics of multi-stage series PV arrays and multi-stage parallel PV arrays under complex illumination are analyzed by using the peak point approximation calculation method, and the distribution law of peak voltage points as well as the I-V (Current-Voltage) characteristic equation of each operating section are proposed. On this basis, the output characteristics of 3 x 3 centralized PV arrays are analyzed and verified by simulation. By comparing series and parallel PV arrays with the same condition, as well as several groups of centralized PV arrays with the same topology and different types of illumination distribution, this paper proposes a configuration optimization method for PV arrays. Matlab/Simulink simulation results confirm that the output power of parallel arrays is greater than that of series arrays under the same configuration and illuminationt distribution type, and the peak point is less than that of series arrays under the same configuration and lighting conditions; while in centralized PV arrays, the fewer series modules are shaded, the greater the output power and the less the peak point.
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Authors and Affiliations

Liming Wei
1
ORCID: ORCID
KaiKai Li
1
ORCID: ORCID
  1. School of Electrical and Computer Engineering, Jilin Jianzhu University, Changchun, Jilin, China

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