Characteristics of High-Power UV Lamps with Electronnic Ballasts

The article briefly describes the structure and the results of measurements of characteristics of low power(LP) amalgamate bactericidal lamps with rated power of 300 W (manufactured by R&D company LIT, Russia) combined with an electronic ballast designed by the authors. Distinctions and characteristics of this apparatus are described.

A Method for Evaluating the Daylighting of Premises Using BIM

The paper presents a method for assessing the daylighting of premises, which can be used directly at the stage of architectural and construction design of buildings in building information model (BIM) software complexes. The calculation method is based on the calculation of the sky factor by constructing a solid angle formed by the calculated point and the light opening of the outer wall. These operations are proposed to be performed automatically using visual programming programs that work together with the BIM complexes. Since the considered calculation method is based on the idea of the physical meaning of the daylight factor, it can be used to evaluate the daylighting according to almost any regulatory method. At the same time, all the data necessary for the calculation can be obtained directly from the building information model. The method is universal and can be used both for the calculation of side and top daylighting, considering the surrounding development. The proposed method can also be used as a tool for finding the best design solution for translucent structures of the designed building based on the requirements of thermal protection, daylighting, and safety.

Definition of Characteristics of Instantaneous Diurnal Activity of Human Body Affected by Solar Radiation in the Circadian Region of Optical Spectrum during Daytime

The article reviews the impact of daily changes in characteristics of solar radiation in the circadian region of optical spectrum on diurnal (circadian) activity of human body with changes of solar altitude angle. Analytical expressions, allowing to theoretically estimation instantaneous melatonin content in human blood plasma and dependence of instantaneous human activity during daytime on solar altitude angle, were obtained.

Analysis of Tungsten Halogen Lamps Characteristics

The authors briefly review distinctions of tungsten halogen lamps (THL) and analyse the results of their own measurements of characteristics of three types of THL manufactured by Saransk lighting equipment plant LISMA. Rated power, luminous flux, and correlated colour temperature of lamps were measured. Relative measurement errors with consideration of possible technological errors for these products do not exceed 0.84 % for values of rated power and 0.29 % for values of correlated colour temperature in batches of 13 pcs. The analysis conducted shows that the technical level of development and production technology of Saransk lighting equipment plant LISMA provides high quality of THL.

The Usage of Solar Power in the Heating Treatment of Concrete

This article proposes the usage of alternative energy instead of traditional, as safer, and environmentally friendly for the planet and all humankind in the manufacture of monolithic concrete and reinforced concrete products. Monolithic concreting in the conditions of the construction site is now widespread in the construction industry. The subject of the article is considered of the issues of heat treatment of concrete and acceleration of its hardening processes using solar energy. A brief review and classification of the most well-known and common energy sources used to harden acceleration of the concrete mix such as wind power, biofuels, solar energy, alternative hydropower is given. For consideration in the article offers the solar energy – the energy received from solar radiation. The sun as a source is an inexhaustible and affordable type of energy that supplies energy several times higher than traditional sources. In this regard, attention is paid to this field of alternative energy when using it in various spheres of the national economy, especially in the field of construction. Already existing methods of heat treatment of concrete with the help of solar technology are considered, the modern level of development of these methods is defined and further ways of their development are planned. As an example, a physical and mathematical model of a non-stationary heat transfer process in a flat reinforced concrete structure during its heat treatment using solar energy, considering the hydration of cement, is considered. Analytical expressions are obtained that allow us to model the process at any stage and actively intervene and adjust the external parameters to create rational and comfortable conditions for increasing the strength of concrete.

The Regularity of the Decrease in the Quantum Yield of Quantum-Wells LEDs at the Long-Term Current Flow from the ABC Model Position

The works on degradation of light emitting diodes (LEDs) with quantum wells (QW) were analysed. The calculation model of the relation between LED luminous flux and duration of LED current flow and current density was proposed. It allows us to forecast service life of such radiators with the pre-set electric modes and temperature. It is demonstrated that: – Reduction of quantum yield of LED with QW based on high-bandgap semiconductors with longterm flow of forward current occurs due to generation of point defects in the QW areas; – The dot defects occur as a result of interaction between hot electrons and semiconductor atoms caused by subthreshold displacement out of the lattice dots; – The dot defects create non-radiative recombination centres with particular concentration in the energy gap of a semiconductor, as a result of which intensities of recombination flows in QWs and in barriers between QWs redistribute towards the non-radiative component of the ABC model.

Autonomous Active Solar Energy Systems for Heat Supply in Housing and Communal Services

Energy saving in small-scale heat power engineering is directed to increasing the efficiency of using fossil energy carriers, electric power, and their wider replacement with alternative sources in housing and communal complex. The practical use of active solar energy systems, both photovoltaic and with direct water heating, has found widespread use. At the same time, the specificities of these systems deployment are caused by climatic and technical conditions of their application. For countries found in climatic zones with temperate and cold climate, water heating installations design is most rational when used seasonally. Low coolant potential, heat supply frequency in active solar energy systems, linked to seasonality of their operation, daytime and weather require several technical solutions. For example, solutions with the use of other equipment in form of thermal energy accumulators, heat pumps and other equipment, which in any case must be combined with a traditional source of thermal energy using fossil fuels or electric power, performing the functions of both other and emergency source of heat energy. Capacity reserving of alternative energy sources is most efficient and least energy-consuming when conducting with heat sources using gaseous or degasified fuel. The use of electric power for heat supply purpose, with few capital investments, requires from a developer significant installed capacities of heat source with a low efficiency for primary fuel. In the article one considers thermal schemes of autonomous heat supply installations for objects using modern condensing boilers of low power and along them various heat cumulating devices, supplying full year operation of equipment at heat supply facilities to get the highest efficiency of energy use.

Luminaires and the History of the Development of Artificial Lighting in Russia

The article is devoted to luminaires and the history of the development of artificial illumination. As you know, light is one of the human needs. At all stages of the development of human civilization, people have thought about how to use artificial light source if there is not enough daylight. That is why man constantly invented and improved certain light source, the framings of which we now call lighting device or luminaires. The stages of development and improvement of luminaires are a matter of separate serious scientific research. In this article, we are talking about how the development of lighting devices took place in different periods. In different epochs, luminaires corresponded to certain traditions and aesthetic views of certain architectural styles. That is why in his article the author pays great attention not only to the appearance of the described luminaires, but also to its architectural environment.

Daylight, Solar Radiation, Architectural Expression, and Energy Efficiency of Buildings

Building design includes a large number of various issues, which must be taken into account in mutual coordination and with optimal consideration of individual factors. Daylighting, insolation, sun protection in hot weather are factors that directly affect the comfort of the indoor environment in buildings and their energy efficiency. It is noted that the above factors also affect the economy through the cost of housing and through operating costs for replenishing heat losses through windows, for ventilation and cooling of buildings, i.e. on the elimination of heat gains through translucent structures, as well as on artificial lighting, for which electricity costs can be comparable depending on the climatic conditions of the construction site and the design features and architecture of buildings, on artificial lighting technology and on technical solutions for air conditioning and ventilation. It provides topics related to daylight, solar radiation, and translucent structures, directly related to building design, partially reflected in the articles of this issue of Light & Engineering journal. Thus, the interrelation of building design issues with various aspects of lighting technologies is indicated.