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Internet of Things is a widespread concept associated with devices equipped with sensors, connected to the Internet, and able to communicate to each other and with the end user. The ultimate goal of Internet of Things is to make people’s lives easier, simpler and safer, and a number of applications that are steering Internet of Things in that direction already exist. This paper presents a brief overview of Internet of Things methodologies and applications that use visual data, i.e. where the main focus is on Internet of Things methodologies and applications where one of the primary sensors that is being used is a digital camera. This sub-field of Internet of Things is also known as Visual Internet of Things. more...

Buildings contribute with 32% to the world's overall energy consumption. Given documented discrepancies between the design and operation of buildings, concepts such as continuous commissioning and performance testing (PTing) have emerged. To increase the applicability and customizability of real-Time performance monitoring, PTing frameworks utilize metadata schemas and generic libraries of tests. However, real-Time PTing requires enhanced instrumentation in the building, such as meters and sensors. Considering the usage and age of buildings, different buildings impose more stringent requirements for sensing equipment in terms of applicability of PTing. Prior work establishes a framework for automatic discovery of performance tests, and their continuous execution without human intervention. In this paper, we provide an algorithm for automatic estimation of the Smart Readiness Indicator (SRI), a metric for measuring the technological readiness of a building proposed by the European Commission. In line with our PTing framework, we estimate a minimal SRI for PTing to be 23%, implying high applicability across a variety of buildings. We evaluate a case study building for its SRI and perform sensitivity analyses of the SRI specific requirements against the PT-SRI. more...

The existing interdependencies between electric power and natural gas networks are getting stronger with the increased penetration of renewable energy sources (RES) and should be considered at both the operational and the planning stage. A powerful simulation model based on an equivalent electrical model of the whole multi-energy system allows simultaneous analysis of these two connected networks in one simulation environment. In this study, the behavior of an ideal, as well as a real natural gas metering and pressure reduction station (MRS), has been analyzed and electric analogy steady state models (i.e. models with electric circuit elements) are given. The verification of the presented model is obtained by 24 examples carried out to cover a wide range of input data, and the simulation results are compared with the results obtained by SIMONE – the commercial software package for gas network simulation that is widely used in Europe. The results have shown a very high precision of the presented model and confirmed the proposed modeling principles, as well as the approach to modeling gas network elements in the electrical analogy. more...

Heat pumps are recognized as energy efficient and environmentally friendly technologies for cooling and heating. The objective of this paper is to identify the economic and environmental potential of seawater heat pump installed in a specialized hospital on the Mediterranean coast. A seawater heat pump is operating in the heating mode throughout the whole year and it is used for pool heating and domestic hot water production. Energy demand was studied for a whole year, and the economic benefits, as well as primary energy savings and CO 2 emissions reduction, were analysed. The analysis showed that the seawater heat pump would lead to 25% lower costs, 52% primary energy savings and 63% of CO 2 emission reduction in comparison to fuel oil boiler. more...

The main goal of this paper is to investigate the effects of environmental stresses on high voltage polymer insulators regarding electric field distribution. For that purpose simulations were carried out, using contemporary software tool COMSOL Mph, for polymer rod type insulator operating under polluted conditions and with presence of water droplets. Simulations were performed for clean insulator, with uniformly deposited contamination layer, with presence of dry band location and presence of water in the form of droplets on the hydrophobic surface of insulator. In order to simulate different types of pollution, the pollution layer is modeled as a conductive layer for different values of its conductivity. The results provided in this paper point out critical spots on the insulator due to the environmental stresses and as such they provide deeper understanding of polymer insulators performances under different polluted conditions from the surrounding ambient. more...

We propose a method of discerning components in multicomponent, stationary and nonstationary signals by application of edge detection techniques to the time-frequency (TF) plane. The approach is based upon the use of a robust to noise computer vision edge detection algorithms, which can be used to precisely mark the position of the component in the TF plane independent of its length, frequency or shape. The results show the proposed method correctly detects positions of stationary signals with low error even in signals heavily corrupted by Additive White Gaussian Noise (AWGN) and other color noise environments, tested for Signal-to-Noise Ratio (SNR)of OdB and 6dB. Positions of nonstationary components in the TF plane are detected with error of less than 6%. Results with synthetic signals and a real-life signal (bat-echolocation) indicate that the method can be used in identifying components in noisy environments using a computationally less costly method that outperforms previously proposed adaptive methods by offering faster computational speed and smaller processor workload. Closer to optimal detection can be achieved with a combination of edge detection operators and thresholded image segmentation procedures. more...

This paper compares the numerical results for the induced electric field and the specific absorption rate (SAR) obtained using the hybrid FEM/BEM method in two detailed models of the human eye. The first model features the human eye placed in the free space, while the second one incorporates the eye model in the realistic head model obtained from the magnetic resonance imaging (MRI) scans. Although the preliminary analysis showed the similar distribution of the induced electric field along the pupillary axis obtained in both models, the numerical results for the SAR showed some discrepancy between the two models, which can be attributed to the high values of induced field in the corneal and scleral regions obtained in the compound eye model. The analysis could provide some helpful insights when carrying out the dosimetric analysis of the human eye exposed to electromagnetic radiation. more...

In this paper, a new numerical algorithm for high-accurate computation of exact Carson formulas is developed. Carson formulas are used for computing of per-unit-length (pul) self and mutual impedances of infinitely long parallel conductors. The proposed algorithm is based on piecewise linear approximation of kernel function and analytical integrations of piecewise-linearized kernel function multiplied by the rest of two integrands. Using proposed numerical algorithm, high-accurate results with desired n-digit accuracy can be easily obtained. Results computed by two approximation methods are compared with high-accurate results computed by proposed numerical algorithm for power frequency. more...