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The purpose of this paper is to present issues related to the design of a modern lighting system based on LED technology. The developed system provides lighting with a high colour rendering index (up to 98); it also has many innovative functions, which make its implementation bring significant energy savings and increase the comfort of work.

In contrast to typical solutions, the dynamic synthesis of white light from six component colours was used in the presented project. This process is controlled by a microcontroller, and there is a colour temperature sensor in the feedback loop. The communication between smart luminaires and sensor modules is provided by means of a ZigBee wireless network.

The correctness of the proposed methodology has been proved by measurements and laboratory tests.

The process of improving the lighting system is continued and significant changes in the spectrum of used sensors are expected.

The proposed system based on mixing light from six components is an innovative solution that besides undoubted advantages entails a more elaborate electronic circuitry. However, good characteristics of the obtained light, as well as the possibility of compensating for changes in colour temperature of natural light and reducing the impact of aging of LEDs, in the authors’ opinion, make the proposed solution find its place on the market.

The proposed solution is original, both in terms of the light mixing technique and advanced functionality offered by the system.

This paper aims to investigate different properties of synthesized perovskite Sm_0.9Sr_0.1CoO_3-δ and its potential for application in potentiometric oxygen sensors.

The powder was obtained through solid-state reaction method and characterized by thermogravimetric/differential thermal analyzer and X-ray diffraction. It was used for both making a paste and pressing into rods for sintering. The prepared paste was deposited on alumina and yttria-stabilized zirconia substrates, by screen printing. Thick film conductivity, bulk conductivity and Seebeck coefficient of sintered rods were measured as a function of temperature. An oxygen concentration cell was fabricated with the screen-printed perovskite material as electrodes.

Electrical conductivity of the bulk sample and thick film increases with the increase in temperature, showing semiconductor-like behavior, which is also indicated by relatively high values of the measured Seebeck coefficient. Estimated values of the activation energy for conduction are found to be of the same magnitude as those reported in the literature for similar composition. An investigation of Nernstian behavior of the fabricated cell confirmed that Sm_0.9Sr_0.1CoO_3-δ is a promising material for application in oxygen potentiometric sensors.

Gas sensor research is focused on the development of new sensitive materials. Although there is scarce information on SmCoO_3-δ in the literature, it is mostly investigated for fuel cell applications. Results of this study imply that Sr-doped SmCoO_3-δ is a good candidate material for oxygen potentiometric sensor.

The purpose of this paper is to present fabrication process of volatile organic compounds (VOCs) sensors based on polypyrrole material deposited on different substrates and to show and compare the responses of the produced sensors to different VOCs.

Polypyrrole sensing layers were prepared by in situ chemical polymerisation on two different substrates: alumina and poly(ethylene terephthalate) (PET). The time of the polymerisation was varied. After film deposition, an interdigitated electrode was screen-printed on the material deposited on the substrate.

It was demonstrated that both polymerisation time and substrate type provide means to vary the sensitivity of polypyrrole-based sensors to VOCs.

VOCs, which are released in manufacturing or use of various products and materials, pose a threat to the environment and human health. Therefore, measures must be taken to control their concentration both in indoor and outdoor air.

Deposition of a conductive polymer film on the substrate via in situ chemical polymerisation followed by screen-printing of an interdigitated electrode on the polymer surface offers a fast and an effective method of chemiresistor-type sensor fabrication.

The purpose of this paper is to report the system solution expressed in the form of a block diagram. In this paper, a multi-functional demonstrator of the interactive system designed to modelling, monitoring and validation of hybrid photovoltaic (PV) systems assisted by fuel cells and thermoelectric generators is presented. Technical parameters of demonstrator components such as: silicon PV modules, fuel cells, thermoelectric generators, gel batteries, control and monitoring systems are described.

The design shows the implementation of PV system modelling by four universal PV module simulators supported by two 65 W fuel cell and 12 modules, 6 W thermoelectric generators battery.

The paper provides practical proof that the combination of PV technology with both thermoelecric generators and fuel cells technologies shows promising results for the development of hybrid PV systems with increased effectiveness and efficiency.

The design idea can be developed for many applications gaining electricity from many distributed sources of wasted energy.

In practice, hybrid systems can be used to support the operation of classic PV systems, for example, working in various climatic conditions.

The proposed model demonstrates new technical solution leading to the enlargement of the PV systems application.