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The subject of this paper is the analysis of possible influence of climate change on the energy performance of building and indoor temperatures. The model is based on the Maison Air et Lumière house, which concept was developed as part of the Model Homo 2020 project. It was a low-energy, single family, detached house. The model was divided into three thermal zones and developed by using SketchUp software. The analysis of the climate change was made on the example of the city in Poland - Kielce and described in the first part of the paper. Dynamic calculations of the building model were performed by using the TRNSYS software. The calculations were made for three different scenarios relating to existing technical systems: ventilation, ventilation + heating, ventilation + heating + cooling. Annual energy consumption and rooms air temperature changes were estimated for each variant. The results showed higher risk of summer discomfort and change in energy balance of building what indicates the need to use the cooling system in the future during the summer to reduce the discomfort of overheating. In the variant without the cooling system, the percentage of time with an indoor temperature above 27°C increased from 23.7% to 44.2% in zone 2. The energy demand for heating was reduced by 23.4% compared to the current climate, and the energy consumption for cooling (with the cooling option) increased significantly by 232% compared to the current demand. Summarizing, research indicates that with global warming, the energy demand for heating will decrease and the cooling demand will increase significantly in order to maintain the required user comfort. [ABSTRACT FROM AUTHOR]

On fifth-generation wireless networks, a potential massive MIMO system is used to meet the ever-increasing request for high-traffic data rates, high-resolution streaming media, and cognitive communication. In order to boost the trade-off between energy efficiency (EE), spectral efficiency (SE), and throughput in wireless 5G networks, massive MIMO systems are essential. This paper proposes a strategy for EE 5G optimization utilizing massive MIMO technology. The massive MIMO system architecture would enhance the trade-off between throughput and EE at the optimum number of working antennas. Moreover, the EE-SE tradeoff is adjusted for downlink and uplink massive MIMO systems employing linear precoding techniques such as Multiple - Minimum Mean Square Error (M-MMSE), Regularized Zero Forcing (RZF), Zero Forcing (ZF), and Maximum Ratio (MR). Throughput is increased by adding more antennas at the optimum EE, according to the analysis of simulation findings. Next, utilizing M MMSE instead of RZF and ZF, the suggested trading strategy is enhanced and optimized. The results indicate that M-MMSE provides the best tradeoff between EE and throughput at the determined optimal ratio between active antennas and active users equipment's (UE). [ABSTRACT FROM AUTHOR]

Nowadays the demand for renewable energy sources is constantly growing. There are several reasons of such state, including requirements for energy-efficient new buildings and reduction of greenhouse gas emissions. An exemplary solution that may help to reduce "traditional" primary energy consumption is local energy source utilization. The article presents a simplified feasibility study of hybrid energy system under Polish law and economic conditions for a self-government unit, that is legally obliged to apply means of energy efficiency improvement. The aim of this paper is to provide a simple algorithm to find optimal hybrid PV and wind power source sizing for a prosumer. Resource data used in analyses are imported from Photovoltaic Geographical Information System and cover a period of one year. The paper includes two different methodologies applied to solve the problem of optimal hybrid energy system sizing. The first approach is heuristic and based on monthly energy balancing while the second is iterative and takes into account hourly energy balance. The results from both methods are compared and verified by HomerPro software, that shows significant differences between two algorithms. At the end economic assessment based on Net Present Value method is performed. [ABSTRACT FROM AUTHOR]

Energy and latency are the significant Quality of Service parameters of ad hoc networks. Lower latency and limited energy expenditure of nodes in the ad hoc network contributes to a prolonged lifetime of the network. Reactive protocols determine the route to the destination using a route discovery process which results in increased delay and increased energy expenditure. This paper proposes a new technique of route discovery, Dynamic Blocking Expanded Ring Search (DBERS) which minimizes time delay and energy required for route discovery process. DBERS reduces energy expenditure and time delay occurring in the existing route discovery techniques of reactive protocols. The performance of DBERS is simulated with various network topologies by considering a different number of hop lengths. The analytical results of DBERS are validated through conduction of extensive experiments by simulations that consider topologies with varying hop lengths. The analytical and simulated results of DBERS are evaluated and compared with widely used route discovery techniques such as BERS, BERS+. The comparison of results demonstrates that DBERS provides substantial improvement in time efficiency and also minimizes energy consumption. [ABSTRACT FROM AUTHOR]

This paper, an energy consumption model is developed and exploited to evaluate the electrical energy consumption of ultra-wideband impulse radio (UWB-IR) systems. We develop the energy consumption models and our comparative study, on the one hand, for a system based single-input singleoutput (SISO) configuration and a multiple-input single-output (MISO) and on the other hand, for a time reversal TR-MISO configuration and for MISO alone configuration. We consider an indoor propagation environment based on the 802.15.4a channel model. The results show very different behaviors depending on the propagation conditions, the number of antennas used, or on the number of transmitted symbols. Using such a model, a radiofrequency designer can obtain significant inputs to optimally select an adequate configuration to design an adaptive energyaware UWB-IR system. [ABSTRACT FROM AUTHOR]

As more and more Base Stations (BSs) are being deployed by mobile operators to meet the ever increasing data traffic, solutions have to be found to try and reduce BS energy consumption to make the BSs more energy efficient and to reduce the mobile networks' operational expenditure (OPEX) and carbon dioxide emissions. In this paper, a BS sleeping technology deployable in heterogeneous networks (HetNets) is proposed. The proposed scheme is validated by using extensive OMNeT++/SimuLTE simulations. From the simulations, it is shown that some lightly loaded micro BSs can be put to sleep in a HetNet when the network traffic is very low without compromising the QoS of the mobile network. [ABSTRACT FROM AUTHOR]

Energy Efficiency (EE) is becoming increasingly important for wireless communications and has caught more attention due to steadily rising energy costs and environmental concerns. Recently, a new network architecture known as Massive Multiple-Input Multiple-Output (MIMO) has been proposed with the remarkable potential to achieve huge gains in EE with simple linear processing. In this paper, a power allocation algorithm is proposed for EE to achieve the optimal EE in Massive MIMO. Based on the simplified expression, we develop a new algorithm to compute the optimal power allocation algorithm and it has been compared with the existing scheme from the previous literature. An improved water filling algorithm is proposed and embedded in the power allocation algorithm to maximize EE and Spectral Efficiency (SE). The numerical analysis of the simulation results indicates an improvement of 40% in EE and 50% in SE at the downlink transmission, compared to the other existing schemes. Furthermore, the results revealed that SE does not influence the EE enhancement after using the proposed algorithm as the number of Massive MIMO antenna at the Base Station (BS) increases. [ABSTRACT FROM AUTHOR]

Manufacturing engineering is supposed to provide analyses related to various aspects of manufacturing and production in order to maximise technological, energy, and economic gains in relevant production processes. The present paper gives a recapitulation of several publications by present authors, presenting considerations of the energy efficiency of biofuel production. The energy efficiency is understood as the ratio of energy obtained from biofuels produced basing on crops from a particular area to the energy required to satisfy needs of all subsidiary processes assuring correct functioning of the production system, starting from operations aimed to obtain agricultural crops, and ending with the conversion of the crops onto biofuels. Derived by the present authors, the mathematical model of energy efficiency of biofuel production is extended to a more general form, and applied to the analysis of quantitative relations between energy efficiency of sc. "energy plantations", and further elements of biofuel production system converting harvested biomass into biofuel. Investigations are aimed towards the determination of the role of biomass as a source of energy. [ABSTRACT FROM AUTHOR]