In modern society, humans spend most of their time in the indoor environment (home, work, school...). This indoor lifestyle constantly poses challenges to our physical and mental health by affecting our hormone levels and circadian rhythm. This article deals with the possible connection between human and working environment factors and the emergence of health problems in connection with work. Using statistical methods, the dependence between the six characteristics (age, length of employment, visual demand of the work task, satisfaction with lighting conditions, and shift work) and occurrence of health-related problems and discomfort (i.e., eye discomfort, headache, eye fatigue, and seasonal affective disorder symptoms) was examined. The paper also deals with the evaluation of lighting conditions in the workshop using the lighting design software DIALux evo 9.2. Using this software, two lighting variants were modeled. The first simulated variant included lighting parameters according to the currently used luminaries and the second variant contained more efficient LED luminaries.

Gear drives are widely used in various fields and applications due to their properties and capacity. Their versatility, durability, and ability to transmit high torques as well as precision and reliability make them extremely useful in many fields of technology. They are widely used in industrial and energy machinery, vehicle drive systems, aerospace, medical devices, and many other areas. Gears can be manufactured using many technologies. This work focuses mainly on machining with particular emphasis on high-performance new technologies. The process of mathematical modeling of the gear and the machined profile is strongly related to CNC machining technologies. A robust correlation of systems supporting the design and modeling of sliding gears needed for the manufacturing process is presented in the article. It is very important to properly assess gears with correct manufacturing in accordance with a specific standard. The article presents an analysis of available methods for controlling gears using coordinate measurement techniques. Gear machining methods were assessed in terms of the technologies used as well as their productivity and manufacturing tolerance.

Lighting conditions in industrial operations are currently at a level, which in many cases does not satisfy the requirements set out by legislation and standards. Slovakia has highly energy-intensive industrial structure, where dominates the engineering industry. The proportion of electricity attributable to lighting is significant and not negligible. Installation and operation of energy efficient lighting systems is in most cases not yet considered a major priority, because the available funds are primarily used for the operation, modernization of production process, and other related activities, that are directly related to the production, and the existence of industrial enterprises and institutions. This paper presents new trends and progressive strategies to reduce energy consumption of lighting systems. In new installations energy efficient lighting costs are little more to provide than the older less efficient kind, but consumption of energy are lower, economical and environmental friendly

This paper focuses on evaluating lighting conditions in a university classroom used for day and evening classes. The evaluation was made with regard to the legislation requirements for evening classes and adult education. The practical part of this paper consists of illumination measuring and simulation. A RadioLux 111 luxmeter was used to measure the illumination during the absence of daylight, which often occurs, especially in winter during the later hours. The simulation was performed in the DIALux EVO 10.1 and ReluxDesktop lighting design software. In both software, a 3D model of the classroom was created to represent its actual state. The results of the measurement and both simulations were compared with each other and with the requirements of the legislation. The requirements for evening classes have not been met in all three cases; therefore, the lighting simulation tools were used to improve the lighting system design concerning its energy efficiency and costs. This paper points out the benefits of using freely available computer software in the process of the calculation and improvement of lighting systems.

Thermoplastic starch (TPS) consisting of corn starch and glycerol as a plasticizer, and TPS-montmorillonite (MMT) nanocomposite were stored at room temperature in the air with relative humidities (RH) of 11, 55 and 85% for seven weeks. Mechanical testing and dynamic mechanical thermal analysis (DMTA) were performed to detect changes in their mechanical properties. Solid-state NMR spectroscopy monitoring the changes in molecular mobility in the samples provided an insight into relations between mechanical properties and local structure. The results of mechanical testing indicated that the addition of MMT results in the increase in the tensile strength and Young’s modulus while elongation at break decreased, indicating the reinforcing effect of MMT. DMTA experiments revealed a decrease in glass transition temperature of starch-rich phase below room temperature for samples stored at higher RH (55 and 85%). This indicates that absorbed water molecules had additional plasticizing effect on starch resulting in higher mobility of starch chain segments. Recrystallization in these samples was deduced from the shape of cross-polarization magic-angle spinning ¹³C NMR spectra. The shape of broad-line ¹H NMR spectra reflected changes in molecular mobility in the studied samples during seven weeks of storage and revealed that a high amount of water molecules impacts the starch intermolecular hydrogen bond density.