The electromagnetic radiation from fresh and saltwater (18 %) surfaces at a frequency of 15 GHz was experimentally studied over the temperature range of (30–50) °C. It is shown that the dependence of the radiation power on temperature is linear, with the temperature gradient for fresh water (0.107 rel. units / °C) being greater than that for the saline solution (0.077 rel. units / °C). For this frequency range, fluctuations in radiation power were recorded for the first time at approximately 30 °C, which are presumably associated with the disappearance of the “light” water fraction. A corresponding theoretical analysis was performed using the laws of ray optics (Snell’s law) and the model of Stogryn for the dielectric constant. It was established that the radiation is formed within a surface temperature film, which thickness exceeds the skin depth. It is shown that the difference in the radiation power of fresh and salt water cannot be explained solely by the difference in their emissivity, indicating the influence of the vertical temperature distribution in the surface layer. The results of the study are important for understanding the heat exchange processes at the water – atmosphere interface and for developing methods for the remote monitoring of water bodies.

1. Röntgen, W.C. Über die Constitution des flüssigen Wassers // Ann. Phys. Chem. N.F., 1892, Bd. 281(1), pp. 91–97.
2. Fumagalli, L., Esfandiar, A., Farbegas, R. et al. Anomalously low dielectric constant of confined water // Science, 2018, Vol. 360 (6395), pp. 1339–1342. DOI: 10.1126/science.aat4191.
3. Debye, P. Polar Molecules / New York: The Chemical Catalogue Company, Inc., 1929, 172 p.
4. Amann-Winkel, K., Bellissent-Funel, M.C., Bove, L.E., Loerting, T., Nilsson, A., Paciaroni, A., Schlesinger D., Skinner, L. X-ray and neutron scattering of water // Chemical reviews, 2016, Vol. 116 (13), pp. 7570–7589.
5. Tielrooij, K.J., Garcia-Araez, N., Bonn, M., Bakker, H.J. Cooperativity in ion hydration // Science, 2010, Vol. 328 (5981), pp. 1006–1009.
6. Bubukin, I.T., Stankevich, K.S. Measurements of the reflectivity and permittivity of water in the film layer of the sea surface in the millimetre wave band // Journal of Communications Technology and Electronics, 2013, Vol. 58, pp. 673–681.
7. Lunkenheimer, P., Emmert, S., Gulich, R., Köhler, M., Wolf, M., Schwab, M., Loidl, A. Electromagnetic-radiation absorption by water // Physical Review E., 2017, Vol. 96, 062607.
8. Stogryn, A.P. Equations for Calculating the Dielectric Constant of Saline Water (Correspondence) // IEEE Transactions on Microwave Theory and Techniques, 1971, Vol. 19, pp. 733–736.
9. Gavrilin, S.N. Dependence of water radiation on temperature at microwaves // Physica Scripta, 2025, Vol. 100 (1), 015966.
10. Gavrilin S.N. and Parfentyeva N.A. Radiation-temperature dependence of water and aqueous solution // Light & Engineering, 2025, Vol. 33, # 2, pp. 111–117.
11. Mallamace, F., Branca, C., Broccio, M., Corsaro, C., Mou, C.Y., Chen, S.H. The anomalous behaviour of the density of water in the range 30 K< T< 373 K // Proceedings of the National Academy of Sciences, 2007, Vol. 104 (47), pp. 18387–18391.
12. Poole, P.H., Sciortino, F., Essmann, U., Stanley, H.E. Phase behaviour of metastable water // Nature, 1992, Vol. 360 (6402), pp. 324–328.
13. Ginzburg, A.I., Zatsepin, A.G., Fedorov, K.N. The fine structure of the thermal boundary layer in water at the water-air interface [Tonkaya struktura teplovogo pogranichnogo sloya v vode na granitse razdela vodavozdukh] // Izvestiya AN SSSR. Physics of the atmosphere and ocean, 1977, Vol. 13, # 12, pp. 1268–1277.
14. Bubukin, I.T., Stankevich, K.S. Remote sensing of a film layer of marine surface in the IR spectral range // Journal of Communications Technology and Electronics, 2012, Vol. 57, pp. 1094–1102.

Lighting is one of the key elements that influence the way viewers perceive artistic works. Despite the importance of this topic, it has long been overlooked by specialists because there was a rigid system of norms and standards established back in the Soviet period. However, over time, these rules should evolve with the development of technology and modern trends. The right choice of lighting allows viewers to delve deeper into a work of art by emphasizing the shape, texture and colour of objects, as well as creating soft, natural shadows and an appropriate atmosphere that helps to better understand the author’s intent. At the same time, traditional lighting methods can cause harsh shadows and glare, which can distort the impression of the artwork. Modern digital technologies provide an opportunity to create virtual expositions available to a large number of viewers, but their realization requires high-quality visualization of synthetic images of sculptures. The use of special programs for calculating illumination and analysing colour characteristics makes it possible to test various lighting options, considering a variety of parameters, and through experimentation to find the most suitable solutions for each specific situation.

1. Boos, G.V. Museum lighting as one of the priorities of the Russian light and engineering industry // Light & Engineering, 2023, Vol. 31, # 1, pp. 4–8.
2. Budak, V., Galliamov, I., Kiselev, D. Comparative analysis of colour appearance models for realistic display of synthetic images // Light & Engineering, 2023, Vol. 31, # 2, pp. 76–80.
3. Li, O.D., Lebedeva, S.M. Modelling of lighting options for sculptures in museum halls [Modelirovaniye variantov osveshcheniya skul’ptur v muzeynykh zalakh] / In: “Innovative lighting technology”, 2022, pp. 75–79.
4. Fairchild, M.D. Colour appearance models / Hoboken: John Willeys & Sons Ltd, 2005. 385 p.
5. https://light-point.club/about/
6. https://www.svetcom.ru/poleznaya-informatsiya/4000–5000 K
7. Budak, V.P., Gallyamov, I.R., and Kiselyov, D.A. Comparative analysis of colour perception models for realistic rendering of synthetic images // Light & Engineering, 2023, Vol. 31, # 5, pp. 4–9.
8. Gusev, A.N., Utochkin, I.S. Psychological measurements: Theory. Methods: General psychological practice [Psychological measurements: Theory. Methods: General psychological practice] / Moscow: Aspect Press, 2011. 317 p.
9. Shchepetkov, N.I. Architectural lighting in museums // Light & Engineering, 2019, Vol. 27, # 4, pp. 43–52.
10. Chernyak, A. Sh., Kuznetsova, A.B., and Bartsev, A.A. Measurement of illumination parameters of the halls and exhibited items of the state hermitage and the state Tretyakov gallery // Light & Engineering, 2019, Vol. 27, # 4, pp. 66–72.
11. Atasyan, D.A., Shleyuk, S.G., Principles of Modern organization of museum and exhibition space lighting [Printsipy sovremennoy organizatsii osveshcheniya muzeynykh i vystavochnykh prostranstv] / In: “Sociohumanitarian innovations: strategies of fundamental and applied scientific research”, 2021, pp. 847–851.
12. Kotik, G.G., Matveev, A.B., Pereima, V. V., Tokhadze, I.L. Categorical assessments of lighting quality and their interrelation on a psychometric scale [Kategorial’nyye otsenki kachestva osveshcheniya i ikh vzaimosvyaz’ po psikhometricheskoy shkale] // Svetotekhnika, 1975, # 7, pp. 3–5.

The article presents the results of a study of the buildings of the latest mosques to identify common techniques and patterns of daylighting systems. The options for illuminating the wall of the Qibla and the main prayer niche of the mihrab with overhead and side lights, including through a spatial grid of shanashil or mashrabiya, are shown. Highlighting the mihrab with a directed stream of light is an innovative technique that has been actively used in mosque architecture only in the 21st century. It is noted that in modern houses of worship, the architecture of which demonstrates, it would seem, a clear rejection of traditional Islamic methods, daylight acquires the most important importance, endowing the religious space with semantic and valuable content. The main objects of the study are modern mosque buildings, which at first glance do not fit into the Islamic traditions of architecture, built by architects E. Arolat, A. Kazmaoglu, Cubeinside Bureau, Forum architects, Nakshabid architects and others in the period 2005–2025 in the Middle East and Southeast Asia.

1. Ibragimov, I.A. Spatial-Value Orientation and Visual Dynamics in Christian and Islamic Temple Architecture [Prostranstvenno-cennostnaya orientaciya i vizual’naya dinamika khramovogo zodchestva v khristianstve i islame] / Cand. Sci. (Art Hist.) Diss.: 17.00.09. Saratov, 2011, 262 p.
2. Kononenko, E.I. Mosque Architecture as an Object of Interpretation [Arhitektura mecheti kak ob”ekt interpretacii] // Bulletin of Saint Petersburg University. Arts, 2018, Vol. 8, # 1, pp. 113–131. Doi:10.21638/11701/spbu15.2018.107.
3. Kononenko, E.I. Limits of Mosque ‘Modernization’: The Experience of Turkish Architecture [Predely “modernizaciI” mecheti: opyt tureckoj arkhitektury] // Islamovedenie, 2015, Vol. 6, # 3. [Online]. Available: https://islam.dgu.ru/stat/Islamoved%202015–3–5.pdf (Accessed: 11.02.2025).
4. Burckhardt, T. Art of Islam: Language and Meaning [Iskusstvo islama. Yazyk i znachenie] / Transl. from English by N.P. Lokman. Taganrog: Irbi, 2009, 288 p.
5. Ermolenko, E.V., Pavlov, N.L. Traditional Structures of the Mosque in Contemporary Architects’ Interpretation. Part I: The Mihrab Theme [Nekotorye tradicionnye struktury mecheti v interpretacii sovremennykh arkhitektorov. Chast’ I. Tema Mikhraba] // Architecture and Modern Information Technologies, 2024, # 3(68). [Online]. Available: https://marhi.ru/AMIT/2024/3kvart24/PDF/04_ermolenko.pdf (Accessed: 26.02.2025).
6. Starodub, T. Kh. Treasures of Islamic Architecture [Sokrovishcha islamskoj arkhitektury] / Moscow: White City, 2004, 456 p.
7. Zhemchugova, A.V. Architecture of 20th-Century Catholic Churches in Western Europe: Development Trends and Key Spatial Organization Issues [Arhitektura katolicheskikh khramov Zapadnoj Evropy KHKH veka: Tendencii razvitiya i osnovnye voprosy organizacii prostranstva] / Cand. Arch. Diss. Moscow, 2006, 207 p.
8. Ermolenko, E.V. Daylighting in Contemporary Christian Churches [Estestvennoe osveshchenie novejshikh khristianskikh khramov] // Light & Engineering, 2024, Vol. 32, # 4, pp. 8–15. [Online]. Available: https://l-e-journal.com/en/journals/light-engineering‑29–4/daylightingof-the-newest-christian-churches-l-e-vol‑29‑no‑4–2021/ (Accessed: 11.02.2025).
9. Chervonnaia, S.M. The Contemporary Mosque: Domestic and Global Experience in the Modern Era [Sovremennaya mechet’. Otechestvennyj i mirovoj opyt Novejshego vremeni] / Toruń: Tako, 2016, 478 p.
10. Shukurov, Sh.M. Architecture of the Modern Mosque: Origins [Arhitektura sovremennoj mecheti. Istoki] / Moscow: Progress-Traditsiia, 2014, 202 p.
11. Rizvi, K. The Transnational Mosque: Architecture and Historical Memory in the Contemporary Middle East / Chapel Hill: University of North Carolina Press, 2015, 296 p.
12. Serageldin, I., Steele, J. Architecture of the Contemporary Mosque / London: Wiley, 1996, 177 p. [Online]. Available: https://www.academia.edu/1181015/Architecture_of_the_contemporary_mosque (Accessed: 11.02.2025).
13. Avant-Garde Mosque in Tehran’s Bohemian Quarter Sparks Debate [Avangardnaya mechet’ v bogemnom kvartale Tegerana vyzvala spory]. [Online]. Available: https://islamosfera.ru/en/avangardnaya-mechet-v-bogemnom-rajone-tegerana-vyzvala-spory/ (Accessed: 25.01.2025).
14. Central Mosque of Pristina Competition. [Online]. Available: https://www.archdaily.com/tag/central-mosqueof-pristina (Accessed: 25.01.2025).
15. The Hidden Essence of Things: Sanjaklar Mosque in Istanbul [Skrytaya sut’ veshchej. Mechet’ Sandzhaklar v Stambule]. Arch.ru. [Online]. Available: https://archi.ru/world/60902/skrytaya-sut-veschei (Accessed: 25.01.2025).
16. Nasybullina, R., Samogorov, V. Light-Space: Evolution of Daylight’s Role in Architecture [Svetoprostranstvo. Ehvolyuciya roli estestvennogo sveta v arkhitekture] / Yekaterinburg: TATLIN, 2020, 136 p.
17. Gusev, M.N., Makarevich, V.G. Luminous Architecture [Svetovaya arkhitektura] / Moscow: Stroiizdat, 1973, 248 p.
18. Assyafaah Mosque. [Online]. Available: http://www.forum-architects.com/assyafaah-mosque.html (Accessed: 25.01.2025).

1. Korobko, A.A. Utilitarian outdoor lighting: A training manual [Utilitarnoye naruzhnoye osveshcheniye: uchebnoye posobiye] / Moscow, Editorial Office of the Journal Svetotekhnika / Light & Engineering, 2020, 124 p.
2. Danilko, A.V., Karev, A.V., Lagov, I.S., Stanislav A. Lyapunov, S.A., Pavlov V.A. Protective Glass in the Design of Outdoor Luminaires // Light & Engineering, 2024, Vol. 32, # 2, pp. 43–54.
3. Final Report prepared for the Illuminating Engineering Society of North America, January 2016: Measure and Report Luminaire Dirt Depreciation (Ldd) in LED Luminaires for Street and Roadway Lighting Applications; https://moodle.polymtl.ca/pluginfile.php/512391/mod_resource/content/3/RES‑1–16.pdf.
4. Davis, R.G., Wilkerson, A.M., Kinzey, B.R. Luminaire Dirt Depreciation (LDD): Field Data from Several Exterior Lighting Projects // LEUKOS, 2019, 15:1, pp. 55–63; https://www.tandfonline.com/doi/full/10.1080/15502724.2018.1517598.
5. FHWA report: Design Criteria for Adaptive Roadway Lighting / The USA, Federal Highway Administration, Research and Technology Report, July 2014; https://www.fhwa.dot.gov/publications/research/safety/14051/003.cfm.
6. VTRC 20-R31: Safety Benefits and Best Practices for Intersection Lighting / Final Report, Centre for Infrastructure-Based Safety Systems, Virginia Tech Transportation Institute; https://www.researchgate.net/publication/342048440_Safety_Benefits_and_Best_Practices_for_Intersection_Lighting.
7. Jackett, M. and Frith, W. (2013) Quantifying the Impact of Road Lighting on Road Safety – A New Zealand Study / IATSS Research, 36, pp. 139–145; https://doi.org/10.1016/j.iatssr.2012.09.001.
8. Russian Federation standard: GOST R 55706–2023 Road lighting. Classification and requirements.
9. Bukatov, A.S., Kireev, A.V. Installation and operation of lighting systems: A training manual / Moscow, Editorial Office of the Journal Svetotekhnika / Light & Engineering, 2022, 136 p.

The lighting sector has experienced rapid technological advancements in recent years. One of the important products developed in this context is light emitting diode (LED) technologies, which have a high-efficiency factor and can respond to different lighting needs. However, the use of LEDs in lighting causes harmonics. Harmonics are one of the disruptive factors affecting power quality. Harmonics cause overheating, flickering, increased losses, etc. in devices connected to the system. Additionally, harmonics produce undesirable impacts such as errors in digital meters and control systems, and interference in communication systems. Therefore, the analysis of the impacts of LEDs on power quality (PQ) is important. In this study, harmonic measurements of LEDs in the lighting systems of an industrial facility were made. The measurement results were compared with the IEC 61000–3–2 and IEEE 519–2014 harmonic standards. Then, passive LC filters were designed for different harmonic orders and added to the system. Thus, the impacts of LEDs in the lighting system on electrical power quality in an industrial facility were observed and solution methods were investigated by different passive LC filters.

1. Kocaman, B., Rustemli, S. Comparison of LED and HPS Luminaires in Terms of Energy Savings at Tunnel Illumination // Light & Engineering, 2019, Vol. 27, # 3, pp. 67–74.
2. Abdelrahman, A.A., Kamelia, Y., Ibrahim, Y. Harmonics Monitoring Survey on LED Lamps // Renewable Energy and Sustainable Development, 2017, Vol. 3, # 1, pp. 39–45.
3. Akalp, O., Ozbay, H., Efe, S.B. Design and Analysis of High-Efficient Driver Model for LED Luminaires // Light & Engineering, 2021, Vol. 29, # 2, pp. 96–106.
4. Tan, S.T., Sun, X.W., Demir, H.V., DenBaars, S.P. Advances in the LED Materials and Architectures for Energy-Saving Solid-State Lighting Toward Lighting Revolution // IEEE Photonics Journal, 2012, Vol. 4, # 2, pp. 613–619.
5. Radwa, M.A., Carl, N.M.H. Characterization of Commercial LED Lamps for Power Quality Studies // IEEE Canadian Journal of Electrical and Computer Engineering, 2021, Vol. 44, # 2, pp. 94–104.
6. Aurora, G., Sarah, K.R., Math, H.J. Light Intensity Variation (Flicker) and Harmonic Emission Related to LED Lamps // Electric Power Systems Research, 2017, Vol. 146, # 5, pp. 107–114.
7. Zhaoqi, M., Lane, G., Gary, H. Removing the LED Light Strobe Flicker by Proper Driver Designs // Proceedings of the 10th China International Forum on Solid State Lighting, Beijing, China, 2013, pp. 210–213.
8. Fukang, S., Xinxin, Z., Qiansheng, F., Jianxia, X. Experimental Study of Light Intensity Variation of LED Lamp with Flicker and Statistical Characteristics // Optik – International Journal for Light and Electron Optics, 2019, Vol. 193, Art. 163023.
9. IEEE Recommended Practices for Modulating Current in High-Brightness LEDs for Mitigating Health Risks to Viewers, IEEE Standard 1789–2015, 2015, pp. 1–80.
10. Peker, A., Yörükeren, N., Arsoy, A.B. The Harmonic Analysis and Harmonic Impacts Mitigation in Distribution System Using Distributed Generation // Duzce University Journal of Science and Technology, 2017, Vol. 5, pp. 23–33.
11. Vannoy, D.B., McGranaghan, M.F., Halpin, S.M., Moncrief, W.A., Sabin, D.D. Roadmap for Power-Quality Standards Development // IEEE Transactions on Industry Applications, 2007, Vol. 43, # 2, pp. 412–421.
12. Hasan, A., Abdulmajeed, S., Fahad, A., Kiss, P. Numerical Harmonic Modelling of Low Wattage LED Lamps Based on Parameter Estimation Algorithms // ISA Transactions, 2023, Vol. 139, pp. 230–241.
13. Ratnesh, K.P., Tondare, S.P. An AC LED Driver with Improved Total Harmonic Distortion and Power Factor // International Journal of Scientific & Engineering Research, 2016, Vol. 7, # 5, pp. 1532–1538.
14. Rustemli, S., Cengiz, M.S. Active Filter Solutions in Energy Systems // Turkish Journal of Electrical Engineering and Computer Sciences, 2015, Vol. 23, # 5, pp. 1587–1607.
15. Arrillaga, J., Watson, N.R. Power System Harmonics / John Wiley & Sons Ltd, 2003.
16. Özer, İ., Özbay, H., Efe, S.B. Deep Learning Based Harmonic Estimation in LED Illumination Systems // Journal of Engineering Sciences and Research, 2022, Vol. 4, # 2, pp. 328–334.
17. Chiradeja, P., Ngaopitakkul, A., Jettanasen, C. Energy Savings Analysis and Harmonics Reduction for the Electronic Ballast of T5 Fluorescent Lamp in a Building’s Lighting System // Energy and Buildings, 2015, Vol. 97, pp. 107–117.
18. Rustemli, S., Satici, M.A., Sahin, G., Sark, W.V. Investigation of Harmonics Analysis Power System Due to Non-Linear Loads on the Electrical Energy Quality Results // Energy Reports, 2023, Vol. 10, pp. 4704–4732.
19. Khalid, S., Dwivedi, B. Power Quality Issues, Problems, Standards & Their Impacts in Industry with Corrective Means // International Journal of Advances in Engineering & Technology, 2011, Vol. 1, # 2, pp. 1–11.
20. IEEE Recommended Practice and Requirements for Harmonic Control in Electric Power Systems, IEEE Standard 519–2014, 2014.
21. Electromagnetic Compatibility (EMC)  Part 3–2: Limits for harmonic current emissions (equipment input current ≤16 A per phase), IEC Standard 61000–3–2:2001, 2001.

1. Fadeev, V.V. Remote laser sensing of photosynthetic organisms [Distantsionnoye lazernoye zondirovaniye fotosinteziruyushchikh organizmov] // Quantum Electronics [Kvantovaya Elektronika]. 1978, Vol. 5, # 10, pp. 2221–2226.
2. Hoge, F.E., Swift, R.N. Application of the NASA airborne oceanographic lidar to the mapping of chlorophyll and other organic pigments // NASA. Langley Research Centre Chesapeake Bay Plume Study, 1981, 43 p.
3. Reuter, R., Diebel, D., Hengstermann, T. Oceanographic laser remote sensing: measurement of hydrographicfronts in the German Bight and in the Northern Adriatic Sea // International Journal of Remote Sensing, 1993, Vol. 14, # 5, pp. 823–848.
4. Shangguan, M., Guo, Y., Liao, Z. Shipborne single-photon fluorescence oceanic lidar: instrumentation and inversion // Optics Express, 2024, Vol. 32, # 6, pp. 10204–10218; DOI: [10.1364/OE.516523].
5. Glukhovets, D.I., Goldin, Yu.A., Gureev, B.A. Calibration of flow-through fluorimeter PFD‑2 [Kalibrovka protochnogo fluorimetra PFD‑2] // Modern Methods and Means of Oceanological Research (MSOI‑2019): Conference Proceedings [Sovremennyye metody i sredstva okeanologicheskikh issledovaniy (MSOI‑2019): Materialy konferentsii], 2019, pp. 45–48.
6. Jamet, C., Ibrahim, A., Ahmad, Z. et al. Going beyond standard ocean colour observations: lidar and polarimetry // Frontiers in Marine Science, 2019, Vol. 6, Art. 251; DOI: [10.3389/fmars.2019.00251].
7. Chen, S, Chen, P, Ding, L, Pan, D. A new semianalytical MC model for oceanic LIDAR inelastic signals // Remote Sensing, 2023, Vol. 15, # 3, pp. 684.
8. Spence, D.J., Neimann, B.R., Pask, H.M. Monte Carlo modelling for elastic and Raman signals in oceanic LiDAR // Optics Express, 2023, Vol. 31, # 8, pp. 12339–12348; DOI: [10.1364/OE.485077].
9. Pelevin, V., Zlinszky, A., Khimchenko, E., Toth, V. Ground truth data on chlorophyll-a, chromophoric dissolved organic matter and suspended sediment concentrations in the upper water layer as obtained by LIF lidar at high spatial resolution // International Journal of Remote Sensing, 2017, Vol. 38, # 7, pp. 1967–1982; DOI: [10.1080/01431161.2017.1294779].
10. Yermakov, S.M., Mikhailov, G.A. Statistical Modelling [Statisticheskoe modelirovanie] // Moscow: Nauka, 1982, 296 p.
11. Mobley, C.D. Light and Water. Radiative Transfer in Natural Waters // San Diego: Academic Press, 1994, 592 p.
12. Maritorena, S., Morel, A., Gentili, B. Determination of the fluorescence quantum yield by oceanic phytoplankton in their natural habitat // Applied Optics, 2000, Vol. 39, # 36, pp. 6725–6737.
13. Budak, V.P., Zheltov, V.S. Simulation of lighting using local estimations of the Monte-Carlo method // Light & Engineering, 2009, Vol. 17, # 2, pp. 80–85.
14. Budak, V.P., Grimailo, A.V. Energy Calculation of Optical Systems: Direct Monte-Carlo Method Modification // Light & Engineering, 2023, Vol. 31, # 6, pp. 65–69.
15. Cornec, M., Claustre, H., Mignot, A., et al. Deep chlorophyll maxima in the global ocean: Occurrences, drivers and characteristics // Global Biogeochemical Cycles, 2021, Vol. 35, # 4, e2020GB006759.
16. Falkowski, P.G., Lin, H., Gorbunov, M.Y. What limits photosynthetic energy conversion efficiency in nature? Lessons from the oceans // Philosophical Transactions of the Royal Society B: Biological Sciences, 2017, Vol. 372, # 1730, pp. 20160376; DOI: 10.1098/rstb.2016.0376.
17. Lin, H., Kuzminov, F. I., Park, J. et al. The fate of photons absorbed by phytoplankton in the global ocean // Science, 2016, Vol. 351, # 6270, pp. 264–267. DOI: [10.1126/science. aab2213].

This paper proposes a high-efficiency LED driver system powered by photovoltaic (PV) energy, designed to operate under variable irradiance conditions with optimized power conversion. The system integrates a high-frequency Series Resonant Inverter (SRI) controlled by Pulse Density Modulation (PDM), enabling soft switching through zero-voltage and zero-current conditions. A 2.2 kW PV array serves as the energy source, and maximum power point tracking (MPPT) is achieved via a Perturb and Observe (P&O)-based algorithm. This controller simultaneously manages MPPT and inverter operation by adjusting the pulse density in real time according to the irradiance level. To improve system performance,the study implements and compares three modulation strategies: conventional irregular PDM, Enhanced PDM (EPDM), and Improved PDM (IPDM). All methods are developed and simulated in the PSIM environment, using non-ideal parameters to replicate real-world conditions. Simulation results indicate that the proposed control strategies achieve over 99 % efficiency across varying power levels, with IPDM demonstrating the lowest harmonic distortion and resonance current ripple. These results confirm that the proposed PDM-based control approach offers a robust and energy-efficient solution for PV-powered LED drivers, particularly in off-grid or energy-constrained environments.

1. Efe, S.B., Varhan, D. Interior lighting of a historical building by using led luminaires: A case study of fatih Paşa mosque // Light and Engineering, 2020, Vol. 28, # 4, pp. 77–83.
2. Thothadri, M., Sathi, R.R., Ponnurangam, S., Chinnaraj, K. Fractional order PID controlled phase shift modulated interleaved Watkins – Johnson converter-based LED driver with reduced current ripple // Electr. Eng. 2025, 107, 2163.
3. Askari, S., Farzanehfard, H., Maghsoudi, M. Isolated Soft Switched Resonant Led Driver with Constant Output Current and Wide Input Voltage Range // 16th Power Electronics, Drive Systems, and Technologies Conference, PEDSTC 2025, Institute of Electrical and Electronics Engineers Inc.
4. Mukherjee, A., Chandra Bansal, T., Soni, A. Analysis of LED Driver Topologies with Respect to Power Factor and THD // Light & Engineering, 2018, Vol. 26, # 1, pp. 63–72.
5. Pal, A.K., Singha, A.K. A Digital Pulse Frequency Modulation Technique for a Series Resonant Converter-based LED Driver // IEEE Trans Power Electron. 2025, Feb, Vol. 40, # 2, pp. 2797–2808.
6. Akalp, O., Ozbay, H., Efe, S.B. Design and analysis of high-efficient driver model for led luminaires // Light and Engineering, 2021, Vol. 29, # 2, pp. 96–106.
7. Efe, S.B., Ozbay, H., Ozer, I. Experimental Design and Analysis of Adaptive LED Illumination System // Light and Engineering, 2022, Vol. 30, # 4, pp. 63–70.
8. Akdeniz, M., Efe, S.B. Forecasting of Harmonic Distortions in MV Distribution Network Caused by Illumination Devices // Light and Engineering, 2025, Vol. 33, # 2, pp. 64–69
9. Esteki, M., Khajehoddin, S.A., Safaee, A., Li, Y. LED Systems Applications and LED Driver Topologies: A Review // Vol. 11, IEEE Access. Institute of Electrical and Electronics Engineers Inc. 2023, pp. 38324–38358.
10. Tran, D.H., Waheed, Z., Choi, W.A. New Two-Stage Multiple-Parallel-Channel LED Driver Using a CLL – C Resonant Converter and Time Division Control Technique // Energies (Basel), 2025, Mar 1, Vol 18, # 5.
11. Rao, K.V.G., Kiran, K. M., Srikanth G.B. An Independently Controlled Two Output Half Bridge Resonant LED Driver // Electric Power Components and Systems, 2024, Vol. 52, # 7, pp. 1094–1114.
12. Duman, A.C., Güler, Ö. Techno-economic analysis of off-grid PV LED road lighting systems for Antalya province of Turkey // Light & Engineering, 2019, Vol. 27, # 2, pp. 58–66.
13. Kamalapathi, K., Srinivasa, Rao Nayak P., Tyagi, V.K. Design and implementation of dual-source (WPT + PV) charger for EV battery charging // International Transactions on Electrical Energy Systems, 2021, Vol. 31, # 11, pp. 1–29.
14. Yesuraj, S., Yesuraj, J., Muthaiah, P., Balaraman, S. Standalone PV-fed LED Street Lighting Using Resonant Converter // Electric Power Components and Systems, 2017, Vol. 45, # 5, pp. 548–559.
15. Raj, A., Arya, S.R., Gupta, J. Solar PV array-based DC – DC converter with MPPT for low power applications // Renewable Energy Focus, 2020, # 34 (September), pp. 109–119.
16. Sheng, X., Shi, L., Fan, M. An Improved Pulse Density Modulation of High-Frequency Inverter in ICPT System // IEEE Transactions on Industrial Electronics, 2021 Vol. 68, # 9, pp. 8017–8027.
17. Özbay, H. PDM – MPPT based solar powered induction heating system // Engineering Science and Technology, an International Journal, 2020, Vol. 23, # 6, pp. 1397–414.
18. Li, H., Fang, J., Chen, S., Wang, K., Tang, Y. PulseDensity Modulation for Maximum Efficiency Point Tracking of Wireless Power Transfer Systems // IEEE Trans Power Electron, 2018, Vol. 33, # 6, pp. 5492–5501.
19. Karafil, A., Ozbay, H., Oncu, S. Design and Analysis of Single-Phase Grid-Tied Inverter with PDM Mpptcontrolled Converter // IEEE Trans Power Electron, 2020, Vol. 35, # 5, pp. 4756–4766.
20. Sheng, X., Shi, L. An Improved Pulse Density Modulation Strategy Based on Harmonics for ICPT System // IEEE Trans Power Electron, 2020, Vol. 35, # 7, 6810–6819.
21. Esteve, V., Jordan, J., Sanchis-Kilders, E., Dede, E.J., Maset, E., Ejea, J.B., et al. Enhanced Pulse-Density-Modulated Power Control for High-Frequency Induction Heating Inverter // IEEE Transactions on Industrial Electronics, 2015, Vol. 62, # 11, 6905–6914.
22. Kazimierczuk, M.K., Czarkowski, D. Resonant Power Converters / New York, NY, USA: John Wiley & Sons, 2012, 632 p.
23. Karafil, A. Comparison of the various irregular pulse density modulation (PDM) control pattern lengths for resonant converter with photovoltaic (PV) integration // Journal of the Faculty of Engineering and Architecture of Gazi University, 2021, Vol. 36, # 3, pp. 1595–15611.
24. Yue, H., Fang, Z., Xia, Y. PDM Control Strategy of Extremely High Gain ICPT System Applying for Electrical Isolation Aimed at Maximum Efficiency // IECON Proceedings (Industrial Electronics Conference), 2022, 2022-Octob, pp. 1–6.
25. Karafil, A., Ozbay, H., Oncu, S. Comparison of regular and irregular 32 pulse density modulation patterns for induction heating // IET Power Electronics, 2020, (August), pp. 1–12.
26. Lee, W.C., Hwang, D.H. Improved SSJ-MPPT Method for Maximum Power Point Tracking of Photovoltaic Inverter Under Partial Shadow Condition // Journal of Electrical Engineering and Technology, 2019, Vol. 14, # 1, pp. 301–309. Available from: https://doi.org/10.1007/s42835–018–00018–4.
27. Özbay, H., Öncü, S., Kesler, M. SMC-DPC based active and reactive power control of grid-tied three phase inverter for PV systems // Int. J. Hydrogen Energy, 2017 Vol. 42, # 28, pp. 17713–17722.
28. Ozbay, H., Karafil, A., Oncu, S., Kesler, M. PSIM Simulation of Flyback Converter for P&O and IC MPPT Algorithms // European Journal of Engineering and Natural Sciences, 2017, Vol. 2, # 1, pp. 204–209.
29. Abdel-Salam, M., El-Mohandes, M.T., El-Ghazaly, M. An Efficient Tracking of MPP in PV Systems Using a Newly-Formulated P&O-MPPT Method Under Varying Irradiation Levels // Journal of Electrical Engineering and Technology, 2020, Vol. 15, # 1, pp. 501–513.

This paper describes methods for assessment of a glare discomfort which is a critical aspect in lighting design for work and living spaces. Traditional methods work with small homogeneous light sources in three-dimensional space. In contrast, methods based on the analysis of high dynamic range images, obtained as a result of computer simulation, allow for early assessment of visual discomfort at the design stage of buildings. Particular attention is paid to the problem of calculating glare ratings for non-uniform light sources, such as LED lamps or windows with blinds. Improved methods are proposed, including a weighted average summation of pixel brightness for more accurate calculation of the Guth index, as well as a clustering mechanism for glare areas that takes into account spatial proximity and similarity of brightness characteristics. These methods provide a more adequate assessment of visual discomfort based on HDR images, which is confirmed by the results of testing in the Lumicept lighting simulation and photorealistic image generation system.

1. International Lighting Vocabulary (ILV), 2nd edition, 2020. DOI: 10.25039/S017.2020. URL: http:// https://cie.co.at/publications/ilv-international-lighting-vocabulary‑2nd-edition‑0 (accessed 03.06.2025).
2. Hopkinson, R.G. Glare from daylighting in buildings // Applied ergonomics, 1972, Vol. 3, # 4, pp. 206–215.
3. Wienold, J., Christoffersen, J. Evaluation methods and development of a new glare prediction model for daylight environments with the use of CCD cameras // Energy and buildings, 2006, Vol. 38, # 7, pp. 743–757.
4. CIE, Discomfort Glare in the Interior Lighting, Commission Internationale de lE clairage (CIE), Technical committee TC‑3.13, Division 4, Interior Environment and Lighting Design, Vienna Austria, 1992.
5. Rubiño, M. et al. Discomfort glare indices: a comparative study // Applied optics, Vol. 33, # 34, 1994 pp. 8001–8008.
6. Light and Lighting. Lighting of Work Places. Part 1. Indoor Work Place / European Standard. EN 12464–1, European Committee for Standardization (CEN), Brussels, 2011.
7. M. Rea, editor. IES Lighting Handbook, Reference & Application // Illuminating Engineering Society of North America, New York, 1993, Volume 3, page 79.
8. Discomfort glare in the interior working environment, 1983. Publication CIE, No. 55 (TC‑3.4), Commission Internati´onale de l’´Eclairage (CIE), Vienna, Austria, 43 p.
9. Boyce, PR. Human Factors in Lighting / 3rd Edition, Boca Raton, FL: CRC Press, 2014.
10. Hirning, M.B., Isoardi, G.L., Cowling, I. Discomfort glare in open plan green buildings / Energy and Buildings, Vol. 70, 2014, pp. 427–440.
11. Abboushi, B. et al. The position index of overhead LED sources under different spectral power distributions and background luminance / LEUKOS, 2025, Vol. 21, # 1, pp. 65–82.
12. Kim, W., Kim, J. T. A distribution chart of glare sensation over the whole visual field / Building and Environment, Vol. 45, # 4, 2010, pp. 922–928.
13. Tokura, M., Iwata, T., Shukuya, M. Experimental study on discomfort glare caused by windows part 3: Development of a method for evaluating discomfort glare from a large light source // Journal of Architecture and Planning (Transactions of AIJ), Vol. 61, # 489, 1996, pp. 17–25.
14. Kleindienst, S., Andersen, M. The adaptation of daylight glare probability to dynamic metrics in a computational setting / Proceedings of Lux Europa 2009–11th European lighting conference.
15. Ward, G. Real Pixels Graphics Gems / J. Arvo, ed., 1991. pp. 80–83.
16. Coyne, S. et al. The use of high dynamic range luminance mapping in the assessment, understanding and defining of visual issues in post occupancy building assessments // International conference on energy efficiency in commercial buildings (IEECB’08). Frankfurt, Germany, 10–11 April. 2008.
17. Hirning, M., Coyne, S., Cowling, I. The use of luminance mapping in developing discomfort glare research / Journal of Light & Visual Environment, 2010, Vol. 34, # 2, pp. 101–104.
18. Funke, C., Schierz, C. Extension of the unified glare rating formula for non-uniform LED luminaires // Proc. 12th Lux Junior Conf. Ilmenau, 2015, pp. 80–81.
19. Wienold, J. Dynamic simulation of blind control strategies for visual comfort and energy balance analysis / Swiss Federal Institute of Technology in Lausanne, 2007.
20. Pierson, C., Wienold, J., Bodart, M. Daylight discomfort glare evaluation with Eval glare: influence of parameters and methods on the accuracy of discomfort glare prediction / Buildings, 2018, Vol. 8, # 8, p. 94.
21. Dubois, M.C. Impact of shading devices on daylight quality in offices / Simulations with Radiance, 2001.
22. Shin, J. Y., Yun, G.Y., Kim, J.T. View types and luminance effects on discomfort glare assessment from windows / Energy and Buildings, 2012, Vol. 46, pp. 139–145.
23. Hirning, Michael B. The application of luminance mapping to discomfort glare: a modified glare index for green buildings / Diss. Queensland University of Technology, 2014.
24. Lumicept – Hybrid Light Simulation Software. URL: http://www.integra.jp/en (accessed 03.03.2025).

1. Garcia-Sifuentes, Y., Maney, D.L. Reporting and misreporting of sex differences in the biological sciences // Elife, 2021, Vol. 10, # 1, e70817 p. doi:10.7554/ eLife.70817
2. Klein, S.L. et al. Sex inclusion in basic research drives discovery // Proceedings of the National Academy of Sciences, 2015, Vol. 112, # 17, pp. 5257–5258. doi:10.1073/pnas.1502843112
3. Joel, D., McCarthy, M.M. Incorporating Sex As a Biological Variable in Neuropsychiatric Research: Where Are We Now and Where Should We Be? // Neuropsychopharmacology, 2017, Vol. 42, # 2, pp. 379–385. doi:10.1038/npp. 2016.79
4. de Vries, G.J., Forger, N.G. Sex differences in the brain: a whole body perspective // Biology of Sex Differences, 2015, Vol. 6, # 1, 15 p. doi:10.1186/s13293-015-0032-z
5. Vanston, J.E., Strother, L. Sex differences in the human visual system // Journal of Neuroscience Research, 2017, Vol. 95, # 1–2, pp. 617–625. doi:10.1002/jnr.23895
6. Brabyn, L.B., McGuinness, D. Gender differences in response to spatial frequency and stimulus orientation // Perception and Psychophysics, 1979, Vol. 26, # 4, pp. 319–324. doi:10.3758/bf03199887
7. Abramov, I., Gordon, J., Feldman, O., Chavarga, A. Sex and vision I: Spatio-temporal resolution // Biology of Sex Differences, 2012, Vol. 3, # 1, 20 p. doi:10.1186/2042-6410-3-20
8. Kuehni, R.G. Determination of unique hues using Munsell colour chips // Colour Research and Application, 2001, Vol. 26, # 1, pp. 61–66. doi:10.1002/1520-6378(200102)26:1<61:: AID-COL8>3.0.CO;2–7
9. Abramov, I., Gordon, J., Feldman, O., Chavarga, A. Sex and vision II: colour appearance of monochromatic lights // Biology of Sex Differences, 2012, Vol. 3, # 1, 21 p. doi:10.1186/2042-6410-3-21
10. Jameson, K.A., Highnote, S.M., Wasserman, L.M. Richer colour experience in observers with multiple photopigment opsin genes // Psychonomic Bulletin and Review, 2001, Vol. 8, # 2, pp. 244–261. doi:10.3758/bf03196159
11. Rodríguez-Carmona, M., Sharpe, L.T., Harlow, J.A., Barbur, J.L. Sex-related differences in chromatic sensitivity // Visual Neuroscience, 2008, Vol. 25, # 3, pp. 433–440. doi:10.1017/s095252380808019x
12. Jordan, G., Deeb, S.S., Bosten, J.M., Mollon, J.D. The dimensionality of colour vision in carriers of anomalous trichromacy // Journal of Vision, 2010, Vol. 10, # 8, 12 p. doi:10.1167/10.8.12
13. Nagy, A.L., MacLeod, D.I., Heyneman, N.E., Eisner, A. Four cone pigments in women heterozygous for colour deficiency // Journal of the Optical Society of America, 1981, Vol. 71, # 6, pp. 719–722. doi:10.1364/JOSA.71.000719
14. Jordan, G., Mollon, J.D. A study of women heterozygous for colour deficiencies // Vision Research, 1993, Vol. 33, # 11, pp. 1495–1508. doi:10.1016/0042-6989(93)90143-K
15. Hurlbert, A.C., Ling, Y. Biological components of sex differences in colour preference // Current Biology, 2007, Vol. 17, # 16, pp. R623-R625. doi:10.1016/j.cub.2007.06.022
16. Shields, S. Functionalism, Darwinism, and the Psychology of Women: A Study in Social Myth // American Psychologist, 1975, Vol. 30, # 7, pp. 739–754. doi:10.1037/h0076948
17. Wierenga, L.M. et al. A Key Characteristic of Sex Differences in the Developing Brain: Greater Variability in Brain Structure of Boys than Girls // Cerebral Cortex, 2017, Vol. 28, # 8, pp. 2741–2751. doi:10.1093/cercor/bhx154
18. Arden, R., Plomin, R. Sex differences in variance of intelligence across childhood // Personality and Individual Differences, 2006, Vol. 41, # 1, pp. 39–48. doi:10.1016/j.paid.2005.11.027
19. Johnson, W., Carothers, A., Deary, I.J. Sex Differences in Variability in General Intelligence: A New Look at the Old Question // Perspectives on Psychological Science, 2008, Vol. 3, # 6, pp. 518–531. doi:10.1111/j.1745-6924.2008.00096.x
20. Lehre, A.-C., Lehre, K.P., Laake, P., Danbolt, N.C. Greater intrasex phenotype variability in males than in females is a fundamental aspect of the gender differences in humans // Developmental Psychobiology, 2009, Vol. 51, # 2, pp. 198–206. doi:10.1002/dev.20358
21. Borkenau, P., McCrae, R.R., Terracciano, A. Do men vary more than women in personality? A study in 51 cultures // Journal of Research in Personality, 2013, Vol. 47, # 2, pp. 135–144. doi:10.1016/j.jrp.2012.12.001
22. Hyde, J.S. Gender Similarities and Differences // Annual Review of Psychology, 2014, Vol. 65, pp. 373–398. doi:10.1146/annurev-psych-010213-115057
23. Baye, A., Monseur, C. Gender differences in variability and extreme scores in an international context // Large-scale Assessments in Education, 2016, Vol. 4, # 1, 1 p. doi:10.1186/s40536-015-0015-x
24. Hedges, L.V., Nowell, A. Sex Differences in Mental Test Scores, Variability, and Numbers of High-Scoring Individuals // Science, 1995, Vol. 269, # 5220, pp. 41–45. doi:10.1126/science.7604277
25. Summers, V. Sex differences in number of X chromosomes and X-chromosome inactivation in females promote greater variability in hearing among males // Biology of Sex Differences, 2022, Vol. 13, # 1, 35 p. doi:10.1186/s13293-022-00457-9
26. Neitz, J., Neitz, M. The genetics of normal and defective colour vision // Vision Research, 2011, Vol. 51, # 7, pp. 633–651. doi:10.1016/j.visres.2010.12.002
27. Helson, H., Lansford, T. The Role of Spectral Energy of Source and Background Colour in the Pleasantness of Object Colours // Applied Optics, 1970, Vol. 9, # 7, pp. 1513–1562. doi:10.1364/AO.9.001513
28. Averchenkov, V.I., Kondratenko, S.V., Potapov, L.A., Spasennikov, V.V. A Mathematical Model of the Colour Preference Scale Construction in Quality Management at the Machine-Building Enterprise // Journal of Physics: Conference Series, 2017, Vol. 803, # 1, 012010 p. doi:10.1088/1742-6596/803/1/012010
29. Hallock, J. Colour Assignment, 2003, URL: https:// www.joehallock.com/?page_id=1281#
30. Farnsworth, D. The Farnsworth-Munsell 100-Hue and Dichotomous Tests for Colour Vision // Journal of the Optical Society of America, 1943, Vol. 33, # 10, pp. 568–578. doi:10.1364/JOSA.33.000568
31. Li, Z. et al. A methodological validation of psychophysical approaches for quantifying the colour discrimination capability of white light sources // Colour Research and Application, 2022, Vol. 47, # 6, pp. 1392–1401. doi:10.1002/col.22826
32. Liu, Y. et al. Optimising colour preference and colour discrimination for jeans under 5500 K light sources with different Duv values // Optik, 2020, Vol. 208, 163916 p. doi:10.1016/j.ijleo.2019.163916
33. Esposito, T., Houser, K. A new measure of colour discrimination for LEDs and other light sources // Lighting Research and Technology, 2019, Vol. 51, # 1, pp. 5–23. doi:10.1177/1477153517729200
34. Königs, S., Mayr, S., Buchner, A. A common type of commercially available LED light source allows for colour discrimination performance at a level comparable to halogen lighting // Ergonomics, 2019, Vol. 62, # 11, pp. 1462–1473. doi:10.1080/00140139.2019.1663940
35. Pardo, P.J., Suero, M.I., Perez, A.L., Martinez-Borreguero, G. Optimization of the correlated colour temperature of a light source for a better colour discrimination // Journal of the Optical Society of America A, 2014, Vol. 31, # 4, pp. A121-A124. doi:10.1364/JOSAA.31.00A121
36. Liu, Q. et al. The Impact of Correlated Colour Temperature of LED Light Source on Colour Discrimination // China Illuminating Engineering Journal, 2015, Vol. 26, # 3, pp. 41–46.
37. Liu, Y. et al. Extending the colour discrimination metric with consideration of illuminance level // Optics Letters, 2022, Vol. 47, # 8, pp. 1851–1854. doi:10.1364/OL.454786
38. Huang, Z. et al. Light dominates colour preference when correlated colour temperature differs // Lighting Research and Technology, 2018, Vol. 50, # 7, pp. 995–1012. doi:10.1177/1477153517713542
39. Huang, Z. et al. Best lighting for jeans, part 1: Optimising colour preference and colour discrimination with multiple correlated colour temperatures // Lighting Research and Technology, 2019, Vol. 51, # 8, pp. 1208–1223. doi:10.1177/1477153518816125
40. Huang, Z. et al. White lighting and colour preference, Part 1: Correlation analysis and metrics validation // Lighting Research and Technology, 2020, Vol. 52, # 1, pp. 5–22. doi:10.1177/1477153518824789
41. Wang, Y. et al. Interactive effect of illuminance and correlated colour temperature on colour preference and degree of white light sensation for Chinese observers // Optik, 2020, Vol. 224, 165675 p. doi:10.1016/j.ijleo.2020.165675
42. Liu, Q. et al. A Field Study of the Impact of Indoor Lighting on Visual Perception and Cognitive Performance in Classroom // Applied Sciences, 2020, Vol. 10, # 21, 7436 p. doi:10.3390/app10217436
43. Huang, Z. et al. Gender Difference in Colour Preference of Lighting: A Pilot Study // Light & Engineering, 2020, Vol. 28, # 4, pp. 111–122. doi:10.33383/2019-100
44. Chen, W. et al. The impact of illuminance level, correlated colour temperature and viewing background on the purchase intention for bread and cakes // Food Quality and Preference, 2022, Vol. 98, 104537 p. doi:10.1016/j.foodqual.2022.104537
45. Mayr, S., Maja, K., Buchner, A. Comparing colour discrimination and proofreading performance under compact fluorescent and halogen lamp lighting // Ergonomics, 2013, Vol. 56, # 9, pp. 1418–1429. doi:10.1080/0014 0139.2013.819940
46. Boyce, P.R. Illuminance, lamp type and performance on a colour discrimination task // Lighting Research and Technology, 1976, Vol. 8, # 4, pp. 195–199. doi:10.1177/14771535760080040401
47. Boyce, P.R., Simons, R.H. Hue discrimination and light sources // Lighting Research and Technology, 1977, Vol. 9, # 3, pp. 125–140. doi:10.1177/096032717700900301
48. Khanh, T., Bodrogi, P., Vinh, Q., Guo, X., Anh, T. Colour preference, naturalness, vividness and colour quality metrics, Part 4: Experiments with still life arrangements at different correlated colour temperatures // Lighting Research and Technology, 2018, Vol. 50, # 6, pp. 862–879. doi:10.1177/1477153517700705
49. Chen, W. et al. Evaluating the colour preference of lighting: the light booth matters // Optics Express, 2020, Vol. 28, # 10, pp. 14874–14883. doi:10.1364/OE.390353
50. Hyde, J.S., Lindberg, S.M., Linn, M.C., Ellis, A.B., Williams, C.C. Gender Similarities Characterize Math Performance // Science, 2008, Vol. 321, # 5888, pp. 494–495. doi:10.1126/science.1160364
51. Lindberg, S.M., Hyde, J.S., Petersen, J.L., Linn, M.C. New trends in gender and mathematics performance: a meta-analysis // Psychological Bulletin, 2010, Vol. 136, # 6, pp. 1123–1135. doi:10.1037/a0021276
52. Thöni, C., Volk, S. Converging evidence for greater male variability in time, risk, and social preferences // Proceedings of the National Academy of Sciences, 2021, Vol. 118, # 8, e2026112118 p. doi:10.1073/pnas.2026112118
53. Ritchie, S.J. et al. Sex Differences in the Adult Human Brain: Evidence from 5216 UK Biobank Participants // Cerebral Cortex, 2018, Vol. 28, # 8, pp. 2959–2975. doi:10.1093/cercor/bhy109
54. Wierenga, L.M. et al. Greater male than female variability in regional brain structure across the lifespan // Human Brain Mapping, 2022, Vol. 43, # 1, pp. 470–499. doi:10.1002/hbm.25204
55. Else-Quest, N., Hyde, J., Goldsmith, H., Van Hulle, C. Gender Differences in Temperament: A Meta-Analysis // Psychological Bulletin, 2006, Vol. 132, # 1, pp. 33–72. doi:10.1037/0033-2909.132.1.33
56. Li, J., Hu, L., Huang, Y., Wang, T., Shao, R. A Study of Healthy Lighting for Learning Performance and Visual Fatigue in School-Aged Children with Reading and Writing Tasks // Light & Engineering, 2025, Vol. 33, # 1, pp. 6–14. doi:10.33383/2024-077
57. Wang, T., Hu, W., Wang, Y., Li, J., Liu, Y. Visual Perception and Alertness in Dependence on CCT for LED Lighting in Classroom [in Russian] // Light & Engineering 2025, Vol. 33, # 1, pp. 15–20. doi:10.33383/2024-058
58. Arnold, A.P. The organizational – activational hypothesis as the foundation for a unified theory of sexual differentiation of all mammalian tissues // Hormones and Behavior, 2009, Vol. 55, # 5, pp. 570–578. doi:10.1016/j.yhbeh.2009.03.011
59. Joel, D. et al. Sex beyond the genitalia: The human brain mosaic // Proceedings of the National Academy of Sciences, 2015, Vol. 112, # 50, pp. 15468–15473. doi:10.1073/pnas.1509654112
60. McCarthy, M.M., Arnold, A.P. Reframing sexual differentiation of the brain // Nature Neuroscience, 2011, Vol. 14, # 6, pp. 677–683. doi:10.1038/nn.2834
61. Tian, B. et al. Assessment of colour preference, purchase intention and sexual attractiveness of lipstick colours under multiple lighting conditions // Frontiers in Neuroscience, 2023, Vol. 17, 1280270 p. doi:10.3389/fnins.2023.1280270

This study examines the interdisciplinary synthesis of light, sound, kinetics, and digital media in 21st-century installation art through analysis of works by leading European, Russian, and Asian practitioners. Applying structural, semantic, comparative, and technological methodologies, the research investigates ten significant installations that demonstrate innovative applications of both daylight and electric light in creating emotionally powerful three-dimensional environments. These case studies reveal four fundamental artistic-technical approaches: theatricality (dynamic light-soundmechanics integration), spontaneity (incorporating natural kinetic elements), contrast (juxtaposing geometric and organic forms), insiderism (active viewer immersion). Findings demonstrate how contemporary artists are expanding sensory perception through multisensory environments that transcend traditional visual paradigms.
A central comparative analysis focuses on two conceptually related works – Russian Field and The Day We Left Field – connected through their shared ‘field’ terminology and agrarian themes.
The research incorporates unique primary data obtained through interviews with Signatura Studio artists, offering new insights into creative processes behind light-based installations.

2. Groys, B. Media art in the museum // Moscow Art Magazine, 2023, 88 p.
3. Herrmann, H.-C.V. Metamechanics: Jean Tinguely’s machine theatre // Logos, 2010, Vol. 74, # 1, pp. 133–144.
4. Koleychuk, V. Kinetism [Kinetizm] // Galart, 1994.
5. Shchepetkov N.I. Physics of light in future architecture // Architecture and Modern Information Technologies, 2021, Vol. 54, # 1, pp. 248–261.
6. Shchepetkov, N.I. On the constructive methodological system for visual assessment of illuminated environments [O “konstruktivnoy” metodicheskoj sisteme zritel’nykh ocenok osveshchyonnoj okruzhayushchej sredy] // Svetotekhnika, 2024, # 5, pp. 33.
7. Xu, J. The art of installation in the digital age: From traditional to digital interactive installation // Media art – XXI century: Genesis, art programs, educational issues. Moscow, 2023, pp. 337–346.
8. Eliasson, O. Solar-drawing observatory (Large spheres) [Installation] // https://olafureliasson.net/artwork/solar-drawing-observatory-large-spheres‑2023/
9. Kim, S.-J. To breathe [Installation] // http://www.kimsooja.com/works/timeline:2024
10. Sila Sveta. Hyperfeeling [Installation] // https://www.silasveta.com/projects/the-hyperfeeling-installationballoon-museum
11. teamLab. Massless suns and dark suns [Installation] // https://www.teamlab.art/w/masslesssuns/
12. teamLab. Traces of continuous life [Installation] // https://www.teamlab.art/w/traces-of-continuouslife/
13. Tundra. The day we left field [Installation] // https://www.behance.net/gallery/78998309/THE-DAY-WELEFT-FIELD

The article describes the proposed prototype of a LED device for lighting birds in cages, consisting of a housing, in which a strip of LEDs of different glow colours is placed, and a controlled power supply with the ability to set a radiation power certain level for each colour LEDs. The device electrical and lighting characteristics measurement was carried out at the S.I. Vavilov VNISI (Ltd) and at the Lighting Engineering Department of the NRU MPEI. An analysis of the blue, green, and red LEDs spectral measurement dependence on the different level of brightness showed that the maxima wavelength values practically do not change depending on the current, and are (467–468) nm for blue, 520 nm for green, and 629 nm for red. The absence of a wavelength shift from current, especially for red and green LEDs, may indicate the absence of their active area significant heating, as a result of which no shift of the spectral maxima wavelengths is observed in the operating range of currents, which, in turn, ensures the resulting spectrum stability. The discrepancy between the results of the LED strip colour coordinates measuring with the SPECTRO 320 and with the CL‑70F devices is, on average, satisfactory.

1. Gladin, D., Kavtarashvili, A. Effect of smooth switching the light on/off under intermittent LED lighting on the productivity of laying hens / Bio web of conferences. EDP Sciences, 2022. С. 03003.
2. Kavtarashvili, A., Gladin, D. Vitality and productivity of laying hens under different light flickering frequency of LED lamps / Bio web of conferences. EDP Sciences, 2022. С. 03004.
3. Pilshchikova, Yu.A. Kovalenko, O. Yu., Guseva, E.D., Kudashkina, M.V. Modelling the visual organ relative spectral sensitivity of a biological object to assess the radiation sources effectiveness [Modelirovanie otnositel’noy spektral’noy chuvstvitel’nosti organa zreniya bioob’ekta dlya otzenki effektivnosti istochnikov izlucheniya] // Sovremennye problem nauki I obrazovaniya, 2014, # 4, pp. 183.
4. Pilshchikova, Yu.A. Kovalenko, O. Yu., Ovchukova, S.A. The effect of combined radiation on young poultry [Vliyanie kombinirovannogo izlucheniya na molodniak ptitzy] // Vestnik Federalnogo gosudarstvennogo obrazovatel’nogo uchrezhdeniya vysshego professional’nogo obrazovaniya “Moskovskiy gosudarstvennyy agroinzhenernyy universitet imeni V.P. Goryachkina “, 2012, Issue 2, pp. 29–31.
5. Jarvis, J.R.,, Taylor, N.R., Prescott, N.B., Meeks, I., Wathes, C.M. Measuring and modelling the photopic flicker sensitivity of the chicken (Gallus g. domesticus) // Vision Research, 2002, 42(1), pp. 99–106.
6. Osorio, D., Vorobyev, M., Jones, C.D. Colour vision of domestic chicks // Journal of Experimental Biology, 1990, 202(21), pp. 2951–2959.
7. Gorbunov, А.А., Ivanushkin, А.М., Mikaeva, S.А., Zhuravleva, Yu.А. Research of led RGB light fixture for aquarium lighting with variable emission spectrum [Issledovanie svetodiodnogo RGB svetovogo pribora dlya akvariumnogo osveshcheniya s izmenyaemym spektrom izlucheniya] / Svetotekhnika, 2023, # 2, pp. 71–75.
8. Gorbunov, А.А., Ivanushkin, А.М., Mikaeva, S.А., Zhuravleva, Yu.А. Research of light-emitting diode RGB light fixture for aquarium lighting with variable emission spectrum // Light & Engineering, 2023, Vol. 31, # 5, pp. 30–35.
9. Kuznetzov, E.A., Shavshaev, R.A., Nesterkina, N.P., Zhuravleva, Yu.А. Development and research of LED lighting fixture with smooth regulation of luminous flux [Razrabotka i issledovanie svetodiodnogo osvetitelnogo pribora s plavnym regulirovaniem svetovogo potoka //Avtomatizatsiya. Sovremennye tekhnologii. 2021. Vol. 75. # 5. pp. 200–203.
10. Nemov, V.V., Ashryatov, A.A., Mikaeva, S.A., Zhuravleva, Yu.А. Development and research of a power source for a phyto-irradiator with a variable spectrum [Razrabotka i issledovanie istochnika pitaniya fitoobluchatelya s izmenyaemym spektrom / Spravochnik. Inzhenernyy zhurnal. 2023. # 5 (314). pp. 44–51.
11. Delyan, R.A., Erokhin, M.M., Markova, S.N., Potapov, A.S., Savitskaya, A.G., Terekhov, G.P., Turkin, A.N. Choosing a method for approximating the spectral distribution of colour LEDs and comparing their parameters and characteristics in nominal mode [Vybor metoda approksimatsii spektralnogo raspredeleniya tsvetnykh svetodiodov sravnenie ikh parametrov I kharakteristik v nominalnom rezhime // Svetotekhnika. 2023. # 1, pp. 48–53.
12. Erokhin, M.M., Kamshilov, P.V., Terekhov, V.G., Turkin, A.N. Study of characteristics of LEDs for phytoradiators [Issledovanie kharakteristik svetodiodov dlya fitoobluchateley] // Svetotekhnika. 2019. # 5, pp. 42–48.
13. Shubert, F. Light-emitting diodes [Svetodiody] / Transl. from engl. ed. by А.E. Yunovich, 2‑d edit. M.: FIZMATLIT, 2008, 496 p.
14. Zolina, K.G., Kudryashov, V.E., Turkin, A.N., Yunovich, A.E. Luminescence spectra of blue and green LEDs based on InGaN/AlGaN/GaN multilayer heterostructures with quantum wells [Spektry luminestsentsii golubykh I zelyonykh svetodiodov na osnove mnogosloynykh geterostruktur InGaN/AlGaN/GaN s kvantovymi yamami] // FTP, 1997, Vol 31, # 9, pp. 1055–1061.
15. Kudryashov, V.E., Turkin, A.N., Yunovich, A.E., Zolina, K.G., Nakamura, S. Spectra of superbright blue and green InGaN/AlGaN/GaN light-emitting diodes // Journal of the European Ceramic Society, 1997, Vol. 17, Issues 15–16, pp. 2033–2037.
16. Yunovich, A.E., Kovalev, A.N., Kudryashov, V.E., Turkin, A.N., Zolina, K.G., Kovalev, A.N., Manyachin, F.I. Mechanism of electroluminescence in InGaN/AlGaN/ GaN heterojunctions with quantum wells // Proc. of the 2nd Symp. on III – V Nitride Materials and Processes. Electrochem. Soc., Pennington, NJ. 1998, Vol. 98–02, pp. 83–102.
17. Kudryashov, V.E., Turkin, A.N., Yunovich, A.E., Kovalev, A.N., Manyachin, F.I. Luminescent and electrical properties of InGaN/AlGaN/GaN multiple quantum-well LEDs [Luminestsentnye i elektricheskie svoystva svetodiodov InGaN/AlGaN/GaN s mnozhestvennymi kvantovymi yamami] // FTP, 1999, Vol. 33, # 4, pp. 445–450.

Currently, the primary method for modelling light fields in lighting installations relies on Monte Carlo techniques. However, the conventional direct Monte Carlo approach has significant limitations. A promising solution to these shortcomings lies in local estimation methods, initially developed for radiative transfer problems.
This paper presents a formulation of initial and transitional ray-wandering densities within a scene, enabling local estimation of luminance as well as any other integral light-field characteristic expressible as a linear functional of luminance and a radiation value function defined by the corresponding receiver. By employing an orthonormal basis for this function, the method is extended to optical system modelling in luminaires.
Building on these developments and prior research, the authors propose a universal light-field modelling method applicable to three key areas in lighting practice:
 Optical system simulation,
 Multiple reflection calculations, and
 Light-surface interaction modelling.
The method has been implemented in Light-in-Night, a newly developed simulation program. Its results have been benchmarked against comparable software tools.

1. Apresyan, L. A., Kravtsov, Y.A. Radiation Transfer: Statistical & Wave Aspects / CRC Press (Gordon & Breach), 1996. 272 p. ISBN 978-2881249204.
2. Rosenberg, G.V. Vector-parameter of Stokes [Vektor-parametr Stoksa] // Phys.-Uspekhi. 1955, Vol. 56 (LVI), # 1, pp. 77–110.
3. Rosenberg, G.V. The light beam (Contribution to the theory of the light field) // Phys-Uspekhi. 1977, Vol. 20, # 1, pp. 55–80. DOI: 10.1070/PU1977v020n01ABEH005317.
4. Soret, J.-L. Sur la polarisation atmosphérique // Ann. Chim. Phys. Gauthier-Villars, 1888. V. XIV, # 6, pp. 503–541.
5. Kajiya, J.T. The rendering equation // Proc. 13th Annu. Conf. Comput. Graph. Interact. Tech. SIGGRAPH 1986, pp. 143–150.
6. Goldstein, R.A., Nagel, R. 3-D Visual simulation // Simulation, 1971, Vol. 16, # 1, pp. 25–31.
7. Korobko, A.A., Kushch, O.K. Using the Monte-Carlo method in lighting calculations [Ispol’zovanie metoda Monte-Karlo v svetotekhnicheskikh raschyotakh] // Svetotekhnika, 1986, # 10, pp. 14–17.
8. Frolov, V. et al. The current state of the methods for calculating global illumination in tasks of realistic computer graphics [Sovremennoye sostoyaniye metodov rascheta global’nogo osveshcheniya v zadachakh realistichnoy komp’yuternoy grafiki] // Proc. Inst. Syst. Program, RAS, 2021, Vol. 33, # 2, pp. 7–48.
9. Kalos, M.H. On the Estimation of Flux at a Point by Monte Carlo // Nucl. Sci. Eng. 1963, Vol. 16, # 1, pp. 111–117.
10. Marchuk, G.I. et al. The Monte Carlo Methods in Atmospheric Optics / Berlin – Heidelberg: Springer, 1980, 220 p. ISBN 978-3-540-35237-2. DOI: 10.1007/978-3-540-35237-2.
11. Budak, V. P., Zheltov, V. S., Kalakutsky, T.K. Local estimations of Monte Carlo method with the object spectral representation in the solution of global illumination // Computer Research and Modelling, 2012, Vol. 4, # 1, pp. 75–84. DOI: 10.20537/2076-7633-2012-4-1-75-84.
12. Budak, V.P. et al. Practical Application of Local Estimations: Singularity Removal in the Solution of the Global Illumination Equation // 33rd Int. Conf. Comput. Graph. Vis. 2023, pp. 108–115.
13. Budak, V., Grimailo, A. Light reflection from real surfaces: Probabilistic model of the layer radiance factor // CEUR Workshop Proc. 2020. V. 2744.
14. Ermakov, S. M., Mikhailov, G.A. Kurs statisticheskogo modelirovaniya [Course in Statistical Modeling] / Moscow: Nauka, 1976, 320 p.
15. Sobol’, I.M. Numerical Monte Carlo methods [Chislennye metody Monte-Karlo] / Moscow: Nauka, 1973, 312 p.
16. Budak, V. P., Grimaylo, A.V. Energy calculation of optical systems: direct Monte Carlo method modification // Light & Engineering, 2023, Vol. 31, # 4, pp. 82–85. DOI: 10.18287/2412-6179-LE-1248.
17. Wang, K. et al. Freeform Optics for LED Packages and Applications / Chennai: Wiley, 2017, 372 p.
18. Tikhonov, A.N., Samarsky, A.A. Equations of Mathematical Physics [Uravneniya matematicheskoy fiziki] / 5th ed., stereotyped, Moscow: Nauka, 1977, 736 p.
19. Cencov, N.N. Statistical Decision Rules and Optimal Inference / American Mathematical Society, 1982, 499 p. (Translations of Mathematical Monographs; Vol. 53). ISBN 0-8218-4502-0.
20. Bartsev, A. A., Budak, V.P. Calculation of photometric characteristics of optical systems by the Monte Carlo method in the direct ray tracing [Raschet fotometricheskikh kharakteristik opticheskikh sistem metodom Monte Carlo v pryamom khode luchey] // Svetotekhnika, 1993, # 4, pp. 4–8.
21. Sobolev, V.V. Point light source between parallel planes [Tochechnyi istochnik sveta mezhdu parallel’nymi ploskostyami] // Reports of Academy of Science SSSR, 1944, Vol. XLII, # 4, pp. 175–176.
22. Minin, I.N. Point light source in an absorbing medium between parallel planes [Tochechnyĭ istochnik sveta v pogloshchayushchey srede mezhdu parallel’nymi ploskostyami] // Reports of Academy of Science SSSR, 1960, Vol. 133, # 1, pp. 74–76.
23. Makarov, D.N. Computer modelling methods of lighting installations [Metody komp’yuternogo modelirovaniya osvetitel’nykh ustanovok, Ph. D. Thesis] / Moscow, NRU MPEI, 2007, 19 p.
24. Korobko, A.A. Method for Calculating the Asymmetric Luminous Intensity Distribution for the Road Lighting Luminaire // Light & Engineering Journal, 2023, # 6, pp. 4–12.

Blue ray is the visible light with a wavelength ranging from 415 nm to 490 nm. The short wavelength of blue light indicates that it contains high-energy visible light. This high-energy blue ray can penetrate the cornea of the eyes and has been scientifically proven to cause related eye diseases such as cataracts. Additionally, it can disrupt hormone levels by triggering the brain to release melatonin and affect hormone secretion, thereby impacting sleep quality. Consequently, there is a need for a study on blue light exposure. This paper reports a comparison of blue ray intensity among different types of lamps. The method employed to measure blue ray intensity involves using an averaging spectrometry method. The findings indicate that LED lamps have the highest blue ray intensity when compared to compact fluorescent lamps (CFLs) and incandescent lamps. The key contribution of this paper is to highlight to consumers that incandescent lamps are considered as the safest option, emitting the lowest amount of blue ray.

1. Khan Academy. Light: Electromagnetic waves, the electromagnetic spectrum and photons // Physics Library, 2016, Unit 14, Lesson 1.
2. CIE. Erythema reference action spectrum and standard erythema dose // Colour Research & Application, 1999, Vol. 24, # 2, pp. 158–158.
3. Helmenstine, A.M. The Visible Spectrum: Wavelengths and Colours // ThoughtCo, 2020, April.
4. Walls, H.L., Walls, K.L., Benke, G. Eye disease resulting from increased use of fluorescent lighting as a climate change mitigation strategy // American Journal of Public Health, 2011, Vol. 101, # 12, pp. 2222–2225.
5. American Academy of Ophthalmology. Blue Light and Your Eyes. 2022. Available at: https://www.aao.org/eye-health/tips-prevention/blue-light-digital-eye-strain.
6. Harvard Health Publishing. Blue Light Has a Dark Side. 2020, July. Available at: https://www.health.harvard.edu/staying-healthy/blue-light-has-a-dark-side.
7. Tosini, G., Ferguson, I., Tsubota, K. Effects of blue light on the circadian system and eye physiology // Molecular Vision, 2016, Vol. 22, pp. 61–72.
8. American Optometric Association. Computer Vision Syndrome. 2022. Available at: https://www.aoa.org/patients-and-public/caring-for-your-vision/protecting-your-vision/computer-vision-syndrome.
9. Arnault, E., Barrau, C., Nanteau, C. Phototoxic action spectrum on a retinal pigment epithelium model of age-related macular degeneration exposed to sunlight normalized conditions // PLoS One, 2013, Vol. 8, # 8, e71398 p.
10. Rahman, M.H., Rahman, M.L. Effects of blue light on human health and mitigation techniques: A comprehensive review // Journal of Environmental Management, 2021, Vol. 280, 111697 p.
11. Golebiowski, B., Long, J., Harrison, K., Lee, A., Vaghefi, E. The effects of smartphone use on human eye: A review // Clinical and Experimental Ophthalmology, 2019, Vol. 47, # 1, pp. 8–14.
12. ICNIRP. ICNIRP guidelines on limits of exposure to incoherent visible and infrared radiation // Health Physics, 2013, Vol. 105, # 1, pp. 74–96.
13. Behar-Cohen, F., Martinsons, C., Viénot, F., et al. Light-emitting diodes (LED) for domestic lighting: Any risks for the eye? // Progress in Retinal and Eye Research, 2011, Vol. 30, # 4, pp. 239–257.
14. Smith, A., Johnson, B. Principles and Applications of Spectroscopy / Wiley-Blackwell, 2021.
15. Silverstein, R.M., Webster, F.X., Kiemle, D.J. Spectrometric Identification of Organic Compounds. 7th ed. / John Wiley & Sons, 2015.
16. Nurulain, S., Aziz, N.A., Najib, M.S., Salim, M.R., Manap, H. A review of free fatty acid determination methods for palm cooking oil // Journal of Physics: Conference Series, 2021, Vol. 1921, 012055 p.
17. Song, Y., Ding, S. Infrared spectroscopy and imaging for molecular diagnosis of diseases // Journal of Materials Chemistry B: Materials for Biology and Medicine, 2021, Vol. 9, # 5, pp. 1134–1154.
18. Ernst, R.R., Wüthrich, K. Nuclear magnetic resonance spectroscopy of biological macromolecules // Quarterly Reviews of Biophysics, 1987, Vol. 20, # 1, pp. 1–56.
19. Manap, H., Suzalina, K., Najib, M.S. A potential development of breathing gas sensor using an open path fibre technique // Microelectronic Engineering, 2016, Vol. 164, pp. 59–62.
20. Manap, H., Najib, M.S. A DOAS system for monitoring of ammonia emission in the agricultural sector // Sensors and Actuators B: Chemical, 2014, Vol. 205, pp. 411–415.
21. Mohamad, M., Manap, H. The optimal absorption of bilirubin using an optical fiber sensor // ARPN Journal of Engineering and Applied Sciences, 2015, Vol. 10, # 19, pp. 8762–8764.
22. Shabani, M., Tavakoli, H., Masoumi, M. Applications of UV – Vis spectroscopy in food science: A review // Journal of Food Measurement and Characterization, 2018, Vol. 12, # 2, pp. 903–917.
23. Skoog, D.A., Holler, F.J., Crouch, S.R. Principles of Instrumental Analysis / Cengage Learning, 2014.
24. Sharma, S., Das, A. Applications of nuclear magnetic resonance spectroscopy in food science // Trends in Food Science & Technology, 2021, Vol. 107, pp. 426–438.
25. Keeler, J. Understanding NMR Spectroscopy. 2nd ed. / John Wiley & Sons, 2010.
26. Martinsons, C., et al. Solid-State Lighting: Review of Health Effects / IEA 4E Technology Cooperation Programme, 2024, ISBN 978-1-83654-223-0.

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The Influence of Daylighting on the Architecture of the Newest Mosques: Part I. The Top and Side Lighting of the Mihrab

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