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Wind energy conversion systems have become a key technology to harvest wind energy worldwide. In permanent magnet synchronous generator-based wind turbine systems, the rotor position is needed for variable speed control and it uses an encoder or a speed sensor. However, these sensors lead to some obstacles, such as additional weight and cost, increased noise, complexity and reliability issues. For these reasons, the development of new sensorless control methods has become critically important for wind turbine generators. This paper aims to develop a new sensorless and adaptive control method for a surface-mounted permanent magnet synchronous generator. The proposed method includes a new model reference adaptive system, which is used to estimate the rotor position and speed as an observer. Adaptive control is implemented in the pulse-width modulated current source converter. In the conventional model reference adaptive system, the proportional-integral controller is used in the adaptation mechanism. Moreover, the proportional-integral controller is generally tuned by the trial and error method, which is tedious and inaccurate. In contrast, the proposed method is based on model predictive control which eliminates the use of speed and position sensors and also improves the performance of model reference adaptive control systems. In this paper, the proposed predictive controller is modelled in MATLAB/SIMULINK and validated experimentally on a 6-kW wind turbine generator. Test results prove the effectiveness of the control strategy in terms of energy efficiency and dynamical adaptation to the wind turbine operational conditions. The experimental results also show that the control method has good dynamic response to parameter variations and external disturbances. Therefore, the developed technique will help increase the uptake of permanent magnet synchronous generators and model predictive control methods in the wind power industry.

This article seeks to address the pressing issue of developing the innovative activity of the domestic economy through the use of the potential of small and medium-sized enterprises, which has to do with the possibility of application of existing experience of the more developed foreign countries in order to achieve economic success. The purpose of this study is to examine the trends in the development of innovative activity of small and medium-sized enterprises in Ukraine, as well as to determine the distribution of the total amount of expenditures by areas of innovation. Analysis of the literature on this issue has shown that the economic development of a country depends on many factors, and the use of intellectual potential is quite a significant factor in modern society. The relevance of this issue is supported by the fact that the majority of developed countries that have high levels of national income and are distinguished by the quality of life of the population are introducing the latest innovative inventions and using them appropriately in: production, agriculture, trade and other fields of activity. The research of the development of innovation activity of small and medium-sized enterprises in the article is carried out in the following logical sequence: analysis of small and medium-sized enterprises in Ukraine, analysis of small and medium-sized enterprises of EU countries, evaluation and comparison of innovation activity of Ukraine and EU countries. The methodical tools of the study included methods of statistical analysis. The study period was 2010-2018. The object of analysis is the process of development of innovation activity of small and medium-sized enterprises, as they are the majority of enterprises in Ukraine. The article presents the results of the analysis of the state of innovation the activity of small and medium-sized enterprises, which showed that our country needs significant transformation in this direction. Studies show that increasing the turnover and the production of small and medium-sized enterprises depends on the level of innovative development. The results of the study may be useful for small and medium-sized enterprises.

Introduction - the purpose of the article is to determine the theoretical and legislative bases for the definition and construction of the national innovation system and its subsystems, to establish gaps in the regulatory legal regulation of the economic activity of individual elements - subjects of the NIS. Methods of research - structural and functional methods of analysis are used to determine the existing competence of the participants of the national innovation system of Ukraine and the ability to perform the necessary functions for the system. Methods of analysis and synthesis were used in the study of theoretical models of innovative systems and their structure. The normativist method (formal and legal) was used in the study of the actual state of legislative securing of the NIS. Results of the research - Based on the analyzed scientific sources and on the basis of regulatory acts of Ukraine, it is necessary to distinguish the following NIS subsystems, which require significant legislative regulation: subsystem of generation of knowledge and education, subsystem of production of products and services, subsystem of innovative infrastructure,subsystem «National network technology transfer», Territorial (regional) subsystems. Discussion with the otherscientists- most views on the essence of a NIS can be divided into the following groups: structural approach, subsystem approach, functional and structural. However, these models do not sufficiently address the role of the lowest level of the administrative system - the united territorial communities as the only one as close as possible to the governmental structure. In this direction, it is necessary to extend the limits of financial capacity of territorial communities on the principles of transparency, accessibility, sufficiency. Summary and conclusions - for the harmonious and timely development of the National Innovation System it is necessary to comprehensively approach the legislative regulation of relations in the innovation system and its subsystems, as well asto formulate guidelines for the formation of the system of regulation of innovative activity in the laws.

The article is devoted to the study of spatial forms of organizing innovative infrastructure of Ukraine in terms of sustainable development. In the course of the study, modern trends of innovative development of the regions in Ukraine are highlighted. The peculiarities of implementing innovative policy in the context of smart specialization strategy are analyzed. Diagnostics of processes of formation and development of innovative infrastructure in regions of Ukraine is carried out. A conceptual approach to assessing the level of innovation infrastructure development is proposed.

The article is devoted to the topic of Ukraine’s readiness for innovations in industry 4.0. The article also discusses the concept of the 4th industrial revolution. The proposed methodology for assessing readiness for innovations is based on the annual ranking of The Global Innovation Index of Cornell University, the French Business School and Research Institute (INSEAD), the World Intellectual Property Organization (WIPO) and official EU statistics. An analysis was carried out of Ukraine’s readiness for innovation in comparison with EU countries in the area of "The Conditions for Creating Innovative Potential, Level of Innovation Potential, Conditions for Realization of Innovative Potential, Realization of Innovative Potential". A cluster analysis of countries regarding the level of preparedness for innovation based on the indicators was also made. The strengths and weaknesses of Ukraine as an innovative country are highlighted, practical recommendations are also given for improving the level of innovative development in the country.

Taking into account the oil resources depletion the requirements to fuel consumption of internal combustion engines are now increasing as well as to their reliability and durability. With the continual increase in the number of internal combustion engines in operation, along with the problem of parts of the cylinder piston group wearing out has caused exhaust from such engines to be one of the main source of harmful pollutant emissions in cities. Therefore, environmental requirements have in turn increased dramatically. The engine resource and its efficiency largely depend on the process of fuel combustion in the combustion chamber. Experimental studies aimed to improve the working process on diesel engines by piston insulation have shown an effective decrease in fuel consumption by reducing heat loss and more complete fuel combustion. When oxide ceramic coatings were used on the piston and cylinder head, the maximum power increased and the specific fuel consumption decreased. However ceramic coatings are not widely used due to their peeling. We have developed a technology for the galvanic plasma treatment of pistons, which made it possible to obtain on the pistons surface made of aluminum alloys a ceramic corundum layer with high adhesion to the base metal that does not peel and has electret properties. In 1993, pistons with a corundum surface layer were installed in a shunting diesel locomotive and life-time running tests were conducted. Such pistons increased wear resistance, reduced the wear of cylinder liners, increased the strength of the annular jumpers, and were not prone to burnouts and scuffing. They provided an increase in the resource of the cylinder-piston group of the diesel engine by more than 125 thousand engine hours. The paper provides an analysis of the effect of corundum pistons thermal insulation on significant increasing the, engine power and fuel consumption reduction. Basing on experimental bench studies of a gasoline engine, a tractor diesel engine and long-term operational life tests of diesel engines, an attempt had been made to explain the reasons for the improvement in the engines’ efficiency.

The article analyses the types of waste generated in economy and the possibilities of their management, on the example of Poland. The main focus was on using selected types of waste for methane production. The impact of the decomposing mass of organic waste on the production of greenhouse gases was examined and various types of biogas plants operating in Poland were presented (biogas plants at landfills, biogas plants at sewage treatment plants, agricultural biogas plants). The article also presents the benefits for the economy from the use of methane from methane drainage. Unfortunately, in Poland, methane resources are used to a small extent. In the case of mines, landfills or sewage treatment plants it is related to high costs of constructing methane capture installations, which are not offset by revenues from sales of gas and green certificates. Although much more favourable blue certificates have been introduced for agricultural biogas plants, the obstacle standing in the way of their progress is the lack of local spatial development plans for the places designated for their construction

Agriculture is a risky industry because forces beyond human control influence the quality and profitability of their activities. Farmers' incomes reveal high volatility due to product and crop price as well as catastrophic risks such as natural disasters and diseases. The following paper discusses different methods, also those not specific to EMS, and their exemplary application. An attempt has been made to answer the question of what methods of risk analysis and management are appropriate for agriculture. The goal is to identify methods which can be used in EMS for agriculture, especially in the family farmsteads. The paper is based on the latest, third edition of ISO 14001

This paper presents the modifications that have been made to the sickle insert of the gear pump with internal gearing. This procedure allowed the obtainment of radial compensation. The test stand to plot the characteristics of the pump before, as well as after the first and second modification is discussed. The results of the measurements from the tests conducted are presented. The results obtained confirmed the achievement of radial compensation by cutting the appropriate channel in the sickle insert. As a result, it will be possible to obtain a higher discharge pressure for this type of pump and to increase its efficiency.

Today’s construction market of materials, contractors and building users, places new demands on individual building materials. Undoubtedly one such material is concrete, which is used in almost all construction projects as a binder for building materials. Therefore, it is necessary that this material is constantly subjected to new tests to find ways to improve its properties. Therefore, many scientists attempt to improve properties such as compressive strength, flexural strength and water resistance. One method is to modify the cement matrix with polymers.

Nano- and biotechnologies are the key elements of the complex of NBIC-technologies, developed within the concept of continuous growth of innovations in the context of the transition to the sixth technological mode. The purpose of the article is to study the prospects for the development of nano- and biotechnologies in various sectors of the economy, as well as explore opportunities for accelerating the commercialization of research results in these areas. The article’s relevance is confirmed by the strengthening of the role of nano- and biotechnologies in the sphere of innovation development of countries worldwide. The results of the study have shown that the nanotechnology market has a divergent structure, and the basic characteristic of nanoproducts is their interdisciplinary nature. The world leaders in the production and commercialization of nanotechnologies are the United States, China, Japan, Germany and South Korea. Biotechnologies are developing rapidly as well. Worldwide, the largest number of biotechnologies is created in areas such as health care (biomedicine and biopharmaceuticals), industry and agriculture. The leading countries in the field of development and commercialization of biotechnologies are the United States, France, Germany and South Korea.

The paper shows the results of research aimed to assess the impact of high squeeze pressure on the porosity of AlZn5Mg alloy castings, including its distribution in slab-type castings with dimensions of 25 x 100 x 200 mm. The research was carried out on castings made by two methods: squeeze casting and gravity casting. The pressing was conducted at a pressure of 100 MPa at an initial mould temperature of 200°C. The research identified the middle and outer parts of the casting. Experimental research was preceded by numerical simulation of the casting solidification, then a porosity assessment was carried out using the hydrostatic weighing method, which was supplemented by structural observations. The results of the research showed a two-fold decrease in the porosity in the middle part of the casting which is most exposed to the occurrence of shrinkage voids formed in the final clotting phase. Structural tests revealed the occurrence of dispersed porosity in castings, mainly of shrinkage and / or shrinkage-gas origin. The impact of pressure of 100 MPa during solidification caused fragmentation of the primary structure of castings, which resulted in a higher grain density.

The article considers the current issues of stimulating innovation in the energy sector and rational use of energy resources. A three-level system of problem-oriented management of human resources for stimulating innovation in the energy sector is proposed. The system considers the impact of the human factor on innovative development at the national, regional and enterprise levels. Also, the need to encourage enterprises to hire highly qualified specialists in the sphere of energy saving and energy efficiency is proven. The role of the tax policy in state regulation of the rational use of energy resources and stimulation of innovation in the energy sector is substantiated. The tax incentives for the rational use of energy resources applied in the world practice are grouped. Features of the application of tax incentives (accelerated depreciation, tax credits, tax holidays, and tax reduction) for energy efficiency and energy saving of households and business entities are analyzed. Directions for stimulating innovation in the energy sector for the efficient use of energy resources are offered.

As many programs of scientific and technical cooperation of various fields are being successfully implemented between Ukraine and the EU, the author has set the goal of intensifying relations between Ukraine and Chile in the field of green energy. The cooperation Ukraine has had with the EU serves as an example of future cooperation between Ukraine and Chile. The text explores Chile’s experience in the field of green energy and, through the comparative example of such cooperation between Ukraine and the EU countries, shows that such interaction is a worthwhile endeavor. Based on an analysis of research materials, one of the priority areas of scientific and technical cooperation is the use of non-traditional renewable energy technologies. In Ukraine, and the EU, as well as Chile, there are objective factors (natural, resources, socio-economic, environmental- technological) that concern their development. It is interesting to note Ukraine’s scientific experience and implementation of these technologies and the organizational and economic support of them as priorities in the context of national and regional policy. All aspects of international scientific and technical cooperation, including through the exchange of intellectual products, make it possible to increase the effectiveness of forms of state support, the innovation, production and business activities of Ukraine and the corresponding development of producers and consumers' motivation towards using non-conventional forms of renewable energy technology.

The dissolution of MnO2 from tantalum capacitor scrap using organic acids in various process conditions was studied. The initial materials were of two types: LTC (leaded tantalum capacitors) and SMDTC (surface-mounted device tantalum capacitors). The research materials were prepared by pyrolysis, grinding and sieving and the preparation processes were characterized. Dissolution of MnO2 was carried out with the use of sulfuric acid solutions with the addition of acetic, ascorbic, citric and oxalic organic acids. Results show that the addition of organic acids significantly improves dissolution yields (72-94 vs 90-99 % for H2SO4 and acid mixtures, respectively). In practice, a concentration of organic acid above 1 M results in the complete removal of MnO2.

Many firms from diverse sectors increasingly use artificial intelligence (AI) to strengthen their efficiency by replacing human work. However, many of these advanced automation procedures will become standard tools in the future, and their relatively isolated application will not enable companies to gain a competitive advantage. Drawing on the distinction of data, information, knowledge and intelligence or wisdom, this paper suggests an intelligence-based view of firm performance as an extension of the knowledge-based view and the resource-based view. An intelligence-based perspective underscores the need to integrate AI applications with specific human expertise to complicate imitation by competitors. To sustain a competitive advantage over time, companies further need to develop a meta-intelligence to dynamically renew and recombine their intelligence architecture with multiple types of human and artificial intelligence. An intelligence-based view provides a systematic framework for assessing a firm’s possibilities to profit from AI by generating growth and innovation beyond optimization and efficiency.

This article aims to provide a conceptual framework for small and medium-sized enterprises (SMEs) to evaluate the appropriation of blockchain technology for their business needs and challenges. This conceptual framework aims to respond to the problem of increasing speculations surrounding the blockchain that is considered to be an absolute and innovative solution to many business-related problems. However, this argument might not be realistic for SMEs despite this assumption. The main argument of the article is that SMEs should be skeptical while evaluating the appropriation of this technology for their business needs and they should follow a tailored approach whilst adopting it. Otherwise, the likelihood is high that a short-term and unstructured knowledge management process to adopt blockchain will end up with a waste of resources. The present paper conceptualizes an appropriation framework within nine factors namely, reduction of costs, internalization, digital representation of assets, unalterable data recording, network size, transparent and synchronized ledger, scalability, fair trade, and financing. Given the field’s infancy state of development, the paper relies on a qualitative document analysis involving SME literature and extant literature and white papers of blockchain applications.

In the last decade, design thinking has been discussed as a new paradigm for dealing with complex business problems. The implementation of design thinking is linked with substantial changes in the organizational culture, and becomes visible in new approaches to designing office and learning spaces. To analyze proponents’ perspectives on the implementation process, we adapted Schein’s (1990, 2017) approach of different layers of an organizational culture. In general, two layers in an organization are addressed, namely visible artifacts and behaviors, as well as basic principles to think about approaches to deal with business problems (mindset). In total, eight semi-structured expert interviews were conducted with proponents to learn more about the implementation of design thinking and the architecture of related office spaces. The findings suggest that design thinking addresses both aspects—the provision and inner design of physical space as well as a change of mindset.

The long-term use of plant protection products in agriculture, including pentachlorophenol (PCP), has contributed to their widespread distribution in the natural environment. So far, no cheap and effective techniques for removing chlorophenols by physicochemical or biological methods have been developed. Therefore, alternative methods of neutralizing them are currently being sought. The aim of the study was to investigate the possibility of pentachlorophenol decomposition by high temperature thermohydrolysis. The decomposition process was carried out at a constant pressure of 25 MPa, in the temperature range of 20°C to 500°C and at various volumetric flows of PCP through the reactor. Detailed analysis of the results showed that the process and degree of pentachlorophenol reduction depended on residence time in the reactor and the process temperature. The obtained results indicate that thermohydrolysis in supercritical water is not an effective method to neutralize pentachlorophenol. The high costs of conducting this process together with an average degree of PCP conversion (the conversion of pentachlorophenol at the lowest volumetric flow rate through the reactor reached about 45%) cause that thermohydrolysis at high temperature is not a costeffective method of neutralizing pentachlorophenol.

This article deals with the determination of the stages of development of Ukrainian industries with regard to the factors driving innovation. Based on an analysis of literary sources carried out, the most common indicators of the stages of development of industries have been identified, and it is proposed to classify them into structural, volumetric, dynamic, and innovation ones, given the specificity of the relevant statistical data regarding Ukraine. Calculations have shown that most industries are in a declining phase in terms of the majority of volumetric and innovation criteria. In some industries there are positive trends to intensify the innovation activity of businesses, while the chemical and engineering industries, which have the highest level of technological development, are in a decline phase.

After a short introduction characterizing the general outline of the issue, this paper describes the test results of oil leakage measurements through CVT actuator seals. The research was done using Jatco company's CVT 7 model, the popular gearbox for small passenger cars. Several curves of leakage values are given for both actuators, concerning different conditions such as rotational speed, oil temperature or pressure. In the summary several conclusions are formulated, based on presented test results. The determined maximal value of leakage is about 1 l/min. It emerged that the influence of centrifugal force is negligible. What is more, the observed phenomena are shortly described and projected for more detailed investigation.

The article aims at summarising the state of the art in the efforts of researchers and innovators to find viable solutions to mitigate the urban heat island (UHI) effect. This effect is loosely connected with the greenhouse effect, however, it certainly creates a severe negative synergy together with it. As green roofs are a well-known answer how to address the UHI effect, the ways how to make their massive and global deployment convenient are discussed. Initially, the differences and similarities between urbanisation in developed and developing countries are described. Then the paper depicts solutions, especially synergic ones, for making the dissemination of green roofs viable, such as rainwater and energy harvesting or urban agriculture. Then the authors conclude that retrofitting the existing roofs is the only method for reaching the desired scale and discuss available business models necessary for introducing the prosumer approach to the retrofitting.

In this study a system constituted by seven double skin facades (DSF), three equipped with venetian blinds and four not equipped with venetian blinds, applied in a virtual chamber, is developed. The project will be carried out in winter conditions, using a numerical model, in transient conditions, and based on energy and mass balance linear integral equations. The energy balance linear integral equations are used to calculate the air temperature inside the DSF and the virtual chamber, the temperature on the venetian blind, the temperature on the inner and outer glass, and the temperature distribution in the surrounding structure of the DSF and virtual chamber. These equations consider the convection, conduction, and radiation phenomena. The heat transfer by convection is calculated by natural, forced, and mixed convection, with dimensionless coefficients. In the radiative exchanges, the incident solar radiation, the absorbed solar radiation, and the transmitted solar radiation are considered. The mass balance linear integral equations are used to calculate the water mass concentration and the contaminants mass concentration. These equations consider the convection and the diffusion phenomena. In this numerical work seven cases studies and three occupation levels are simulated. In each case the influence of the ventilation airflow and the occupation level is analyzed. The total number of thermal and indoor air quality uncomfortable hours are used to evaluate the DSF performance. In accordance with the obtained results, in general, the indoor air quality is acceptable, however, when the number of occupants in the virtual chamber increases, the Predicted Mean Vote index value increases. When the airflow rate increases the total of Uncomfortable Hours decreases and, after a certain value of the airflow rate, it increases. The airflow rate associated with the minimum value of total Uncomfortable Hours increases when the number of occupants increases. The energy production decreases when the airflow increases and the production of energy is higher in DSF with venetian blinds system than in DSF without venetian blinds system.

A new bi-directional circuit breaker is presented for medium-voltage dc (MVDC) systems. The Y-source impedance network topology is used to implement the breaker. The current transfer function is derived to show the frequency response and the breaker operation with the high frequencies. Mathematical analysis is achieved with different conditions of coupling among the breaker inductors. The minimum level of the magnetic coupling is determined, which is represented by the null condition. The effect of the turns-ratio on this condition is investigated as well. The breaker is designed with two types of fault conductance slope rates. The Y-source breaker is simulated, and the results verify the breaker operation during the fault condition and the load change. The results also demonstrate the effect of the coupling level on the minimum values of the source current when the fault occurs. Based on the expected fault type in the MVDC systems, the proposed breaker is developed to interrupt the overcurrent due to any of these fault types. A protection scheme is proposed for a 12-bus, two-level micro-grid, where the Y-source breakers are used in the bi-directional zones. The results verify the ability of the breaker to conduct and interrupt the current in both directions of the power flow.

This paper proposed a test bench device to emulate or simulate the electrical impulses of a wave energy converter (WEC). The objective of the study is to reconstruct under laboratory conditions the dynamics of a WEC in the form of an emulator to assess the performance, which, in this case, is the output power. The designed emulator device is programmable, which makes it possible to create under laboratory conditions the operating mode of the wave generator, identical to how the wave generator would work under real sea conditions. Any control algorithm can be executed in the designed emulator. In order to test the performance of the constructed WEC emulator, an experiment was conducted to test its power output against that of a real point-absorber WEC. The results indicate that, although the power output for that of the real WEC was higher than the WEC emulator, the emulator performed perfectly well. The relatively low power output of the emulator was because of the type of algorithm that was written for the emulator, therefore increasing the speed of the motor in the algorithm (code) would result in higher output for the proposed WEC emulator. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

The problem of localization of nodes of a wireless sensor network placed in different physical media (anchor nodes above ground and sensor nodes underground) is addressed in this article. We use time of arrival of signals transmitted between neighboring sensor nodes and between satellite nodes and sensor nodes as the ranging measurement. The localization problem is formulated as a parameter estimation of the joint distribution of the time of arrival values. The probability distribution of the time of arrival of a signal is derived based on rigorous statistical analysis and its parameters are expressed in terms of the location coordinates of the sensor nodes. Maximum likelihood estimates of the nodes’ location coordinates as parameters of the joint distribution of the various time of arrival variables in the network are computed. Sensitivity analysis to study the variation in the estimates with respect to error in measured soil complex permittivity and magnetic permeability is presented to validate the model and methodology.

Nowadays, supplying demand load and maintaining sustainable energy are important issues that have created many challenges in power systems. In these types of problems, short-term load forecasting has been proposed as one of the management and energy supply modes in power systems. In this paper, after reviewing various load forecasting techniques, a deep learning method called bidirectional long short-term memory (Bi-LSTM) is presented for short-term load forecasting in a microgrid. By collecting relevant features available in the input data at the training stage, it is shown that the proposed procedure enjoys important properties, such as its great ability to process time series data. A microgrid in rural Sub-Saharan Africa, including household and commercial loads, was selected as the case study. The parameters affecting the formation of household and commercial load profiles are considered as input variables, and the total household and commercial load profiles of the microgrid are considered as the target. The Bi-LSTM network is trained by input variables to forecast the microgrid load on an hourly basis by recognizing the consumption pattern. Various performance evaluation indicators such as the correlation coefficient (R), mean squared error (MSE), and root mean squared error (RMSE) are utilized to analyze the forecast results. In addition, in a comparative approach, the performance of the proposed method is compared and evaluated with other methods used in similar studies. The results presented for the training phase show an accuracy of R = 99.81% for the Bi-LSTM network. The test and load forecasting stage are performed by the Bi-STLM network, with an accuracy of R = 99.34% and forecasting errors of MSE = 0.1042 and RMSE = 0.3243. The results confirm the high performance of the proposed Bi-LSTM technique, with a high correlation coefficient when compared to other methods used for short-term load forecasting.

In measurement systems operating under various disturbances the probabilistic characteristics of measurement noises are usually known approximately. To improve the observation accuracy, a new approach to the Kalman&rsquo, s filter adaptation is proposed. In this approach, the Covariance Matrix of Measurement Noises (CMMN) is estimated by accurate measurements detected irregularly by the mobile object observation system (from radiofrequency identifiers, etalon reference, fixed points etc.). The problem of adaptive estimation of the observer&rsquo, s noises covariance matrix in the Kalman filter is solved analytically for two cases: mutual noises correlation, and its absence. The numerical example for adaptive filtration of complexing navigation system parameters of a mobile object using irregular accurate measurements is given to illustrate the effectiveness of the proposed algorithm. Coordinate estimating errors have changed in comparison with the traditional scheme from 100 m to 2 m in latitude, and from 200 m to 1.5 m in longitude.

Accurate photovoltaic (PV) power forecasting is crucial to achieving massive PV integration in several areas, which is needed to successfully reduce or eliminate carbon dioxide from energy sources. This paper deals with short-term multi-step PV power forecasts used in model-based predictive control for home energy management systems. By employing radial basis function (RBFs) artificial neural networks (ANN), designed using a multi-objective genetic algorithm (MOGA) with data selected by an approximate convex-hull algorithm, it is shown that excellent forecasting results can be obtained. Two case studies are used: a special house located in the USA, and the other a typical residential house situated in the south of Portugal. In the latter case, one-step-ahead values for unscaled root mean square error (RMSE), mean relative error (MRE), normalized mean average error (NMAE), mean absolute percentage error (MAPE) and R2 of 0.16, 1.27%, 1.22%, 8% and 0.94 were obtained, respectively. These results compare very favorably with existing alternatives found in the literature. Programa Operacional Portugal 2020 and Operational Program CRESC Algarve 2020 grant 01/SAICT/2018. Antonio Ruano acknowledges the support of Fundação para a Ciência e Tecnologia, through IDMEC, under LAETA, grant UIDB/50022/2020. info:eu-repo/semantics/publishedVersion

The most profound requirements of fifth-generation (5G) technology implementations are the architecture design and the radio base station technology to capably run applications such as device-to-device, machine-to machine and internet of things at a reduced latency. Owing to these requirements, the implementation of 5G technology is very expensive to mobile network operators (MNO). In this study we modified the existing 4G network to form a distributed wireless network architecture (DWNA), the picocell and distributed antenna system were modified to support the enabling technology of 5G technology were a multi-edge computer (MEC), software-defined networking (SDN), massive multiple input multiple output (MIMO), ultra-dense network (UDN), Network Functions Virtualization (NFV) and device-to-device (D2D) communication at a reduced cost of ownership, improved coverage and capacity. We present a mathematical model for operational expenditure, capital expenditure and total cost of ownership (TCO) for the DWNA. A mathematical model for DWNA capacity and throughput was presented. Result shows that it is very economical for MNO to rent the space of the tower infrastructure from tower companies. The sensitivity analysis also shows a significant reduction in TCO for both the modified picocell and modified distributed antenna systems.

This paper aims to highlight the potential of solar water heater installations in Morocco. The project involves the comparison of active and passive solutions for energy efficiency in buildings. To this end, a numerical simulation model of solar water heater installations is created under TRNsys. Three hot water demand scenarios (Low, Standard, and High) were taken into account for the six climatic zones defined in the Moroccan thermal regulation of constructions. The same software (TRNsys) is used to model a pilot building consisting of 16 flats. Energy efficiency actions have been applied to the building envelope (insulation and glazing) and simulations are made for the six areas. The simulation results comparing energy and financial savings show the influence of subsidized gas prices on solar water heaters&rsquo, relevance despite significant energy savings. This work proves that solar water heaters will be a primary obligation for Morocco, taking into account changes in butane gas prices.

The present inquiry studies the influence of mass transfer in magnetohydrodynamics (MHD) upper-convected Maxwell (UCM) fluid flow on a stretchable, porous subsurface. The governing partial differential equations for the flow problem are reformed to ordinary differential equations through similarity transformations. The numerical outcomes for the arising non-linear boundary value problem are determined by implementing the successive linearization method (SLM) via Matlab software. The accuracy of the SLM is confirmed through known methods, and convergence analysis is also presented. The graphical behavior for all the parametric quantities in the governing equations across the velocity and concentration magnitudes, as well as the skin friction and Sherwood number, is presented and debated in detail. A comparability inquiry of the novel proposed technique, along with the preceding explored literature, is also provided. It is expected that the current achieved results will furnish fruitful knowledge in industrious utilities and correlate with the prevailing literature.

In recent years, machine learning (ML) tools have gained tremendous momentum and received wide-spread attention in different segments of modern-day life. As part of digital transformation, the power system industry is one of the pioneers in adopting such attractive and efficient tools for various applications. Apparently, a nonthreatening, but slow-burning issue of the electric power systems is the low-frequency oscillations (LFO), which, if not dealt with appropriately and on time, could result in complete network failure. This paper addresses the role of a prominent ML family member, particle swarm optimization (PSO) tuned adaptive neuro-fuzzy inference system (ANFIS) for real-time enhancement of LFO damping in electric power system networks. It adopts and models two power system networks where in the first network, the synchronous machine is equipped with only a power system stabilizer (PSS), and in the other, the PSS of the synchronous machine is coordinated with the unified power flow controller (UPFC), a second-generation flexible alternating current transmission system (FACTS) device. Then, it develops the proposed ML approach to enhance LFO damping for both adopted networks based on the customary practices of statistical judgment. The performance measuring metrics of power system stability, including the minimum damping ratio (MDR), eigenvalue, and time-domain simulation, were used to analyze the developed approach. Moreover, the paper presents a comparative analysis and discussion with the referenced works&rsquo, achieved results to conclude the proposed PSO-ANFIS technique&rsquo, s ability to enhance power system stability in real-time by damping out the unwanted LFO.

Nowadays, by increasing energy demand and considering the importance of environmental issues in recent decades, the use of renewable energies is expanding. Among renewable energies, wind power and its technology are growing and evolving more rapidly. Resource assessment in Iran has revealed the significant potential of wind energy around the country. To further develop wind energy in the country and create large-scale wind power plants, the consideration of distributed power generation using small wind turbines for applications in agricultural and residential use is needed. Conventional small wind turbines and small wind lens turbines have been developed in recent years. In this research project, a small wind lens turbine is designed. The advantages of this turbine are an increased production capacity and reduced cut-in speed and noise pollution. In this study, a lens (or shroud) is added to a small turbine, and the maximized annual energy production (AEP) and minimization of the levelized cost of energy (LCOE) are modeled. We applied the NSGA-II algorithm for optimization to find the best answer. The input parameters in the objective function of the AEP are cut-in, cut-out, rated speeds, scale factor, and shape factor. Additionally, the input parameters in the objective function of the LCOE are the power production, initial capital cost, annual operating expenses, and balance of energy. The results indicate that installing a wind lens turbine in Kish Island led to an LCOE decrease of 56% on average, and we can see an 83% increase in the AEP. In the Firoozkooh area, an average reduction of 59% in the LCOE and 74% increase in the AEP for a wind lens turbine is observed.

This paper presents the effect of grinding wheel contact stiffness on the plunge grinding cycle. First, it proposes a novel model of the generalized plunge grinding system. The model is applicable to all plunge grinding operations including cylindrical, centerless, shoe-centerless, internal, and shoe-internal grinding. The analysis of the model explicitly describes transient behaviors during the ramp infeed and the spark-out in the plunge grinding cycle. Clarification is provided regarding the premise that the system stiffness is composed of machine stiffness and wheel contact stiffness, and these stiffnesses significantly affect productivity and grinding accuracy. The elastic deflection of the grinding wheel is accurately measured and formulas for representing the deflection nature under various contact loads are derived. The deflection model allows us to find the non-linear contact stiffness with respect to the normal load. The contact stiffnesses of four kinds of grinding wheels with different grades and bond materials are presented. Both cylindrical grinding and centerless grinding tests are carried out, and it is experimentally revealed that the time constant at ramp infeed and spark-out is significantly prolonged by reducing the grinding force. It is verified that a simulation of the grinding tests using the proposed model can accurately predict critical parameters like forces and machine deflection during plunge grinding operations. Finally, this paper provides a guideline for grinding cycle design in order to achieve the required productivity and grinding accuracy.

The world is targeting fully renewable power generation by the middle of the century. Distributed generation is the way to increase the penetration level of renewable energies. This paper presents load frequency control of a hybrid tidal, wind, and wave microgrid to feed an isolated island. This research is a step towards 100% renewable energy communities in remote seas/oceans islands. The wave and tidal generation systems model are presented. The study presents load frequency control through three supplementary control strategies: conventional integrators, fractional order integrator, and non-linear fractional order integrator. All the controllers of the microgrid are designed by using a novel black widow optimization technique. The applied technique is compared to other existing state-of-the-art algorithms. The results show that the black widow non-linear fractional integrator has a better performance over other strategies. Coordination between the unloaded tidal system and blade pitch control of both wind and tidal systems are adopted in the microgrid to utilize the available reserve power for the frequency support. Simulation and optimization studies are performed using the MATLAB/SIMULINK 2017a software application.

Vast expansion in consumption is leading to natural resource scarcity and global warming. The integrated management of natural resources, such as food, energy, food (FEW) as one of the most important aspects has been proposed as a solution to meet these challenges. The FEW nexus is a world-wide solution for simultaneously assessing the development and implementation of various approaches focusing on energy, water and food security, sufficiency. This approach is intended to foster sustainable development and improve the quality of life of communities while preserving the natural, human and social capital, address the long-term sustainability challenges and protecting all-natural resources. This paper tries to review some recent research on this topic. For this purpose, first, we describe some facts about demand growth and exponential consumption in these three areas, with emphasis on presented statistics. Then, the most critical research published in this field is reviewed, considering that it took a decade or so before that the original idea was introduced. The most important policymakers of this emerging concept, including committees and conferences, and finally significant challenges and opportunities to the implementation along with future insights, are addressed.

For footwear insoles, high rebound performance is required in some instances such as for running, while softness for comfort is of higher importance during normal walking and standing to minimize high stress. Hence, materials with rebound performance in some scenarios and softness for other scenarios are desired. In this paper, we investigate rebound performance and hardness of composites made of a shear-thickening material and elastic foam. First, a hydrogel type of shear-thickening material (Slime) is characterized to investigate the influence of water content. After that, two particular shear-thickening hydrogels with better rebound performance (but not outstanding in the shear-thickening effect) are selected and integrated into the elastic foam to produce a composite insole. It is found that, as compared with the commercial elastic insole and commercial shear-thickening insole, softer and superior rebound performance can be achieved simultaneously only if the right shear-thickening material is used in the composite. Published version

This paper reviews the energy storage participation for ancillary services in a microgrid (MG) system. The MG is used as a basic empowering solution to combine renewable generators and storage systems distributed to assist several demands proficiently. However, because of unforeseen and sporadic features of renewable energy, innovative tasks rise for the consistent process of MGs. Power management in MGs that contain renewable energy sources (RES) can be improved by energy storage. The energy storage systems (ESSs) have several merits, such as supply and demand balancing, smoothing of RES power generation, enhancing power quality and reliability, and facilitating the ancillary services like voltage and frequency regulation in MG operation. The integration of ESS technology has become a solution to the challenges the power distribution networks face in achieving improved performance. By simplifying a smooth and robust energy balance within the MG, storage devices match energy generation to consumption. MG, and its multidisciplinary portrait of current MG drivers, tasks, real-world applications, and upcoming views are elucidated in this paper.

Data security of present-day power systems, such as the electricity market, has spurred global interest in both industry and academia. The electricity market can either be regulated (state-controlled entrance, policies, and pricing) or deregulated (open for competitors). While the security threats in a deregulated electricity market are commonly known and have been investigated for years, those in a regulated market still have scope for extensive research. Our current work focuses on exploring the data security of the regulated electricity market, and the regulated New Zealand Electricity Market (NZEM) has been considered for this research. Although the chances of cyberattacks on state-controlled regulated electricity market are relatively less, different layers of the current SCADA systems do pose some threats. In this context, we propose a decentralized Ethereum Blockchain-based end-to-end security prototype for a regulated electricity market such as the NZEM. This prototype aims to enhance data security between the different layers of the current SCADA systems. The detailed operation process and features of this prototype are presented in this work. The proposed prototype has prospects of offering improved data security solutions for the regulated electricity market.

The female perspective of implementing failure learning orientation is explored through the analysis of interviews with Canadian female executives of technology firms. The results of this study established several strategies for executives to use for creating an organizational culture that learns from failure. The strategies include, reimagine failure to mitigate negative emotions, focus on the root of the issue, openly discuss strategies and failures, be proactive, encourage risk-taking in experimentation, and finally, provide a calming presence.

The boiling process is utterly fundamental to the design and safety of water-cooled fission reactors. Both boiling water reactors and pressurised water reactors use boiling under high-pressure subcooled liquid flow conditions to achieve high surface heat fluxes required for their operation. Liquid water is an excellent coolant, which is why water-cooled reactors can have such small sizes and high-power densities, yet also have relatively low component temperatures. Steam is in contrast a very poor coolant. A good understanding of how liquid water coolant turns into steam is correspondingly vital. This need is particularly pressing because heat transfer by water when it is only partially steam (‘nucleate boiling’ regime) is particularly effective, providing a great incentive to operate a plant in this regime. Computational modelling of boiling, using computational fluid dynamics (CFD) simulation at the ‘component scale’ typical of nuclear subchannel analysis and at the scale of the single bubbles, is a core activity of current nuclear thermal hydraulics research. This paper gives an overview of recent literature on computational modelling of boiling. The knowledge and capabilities embodied in the surveyed literature entail theoretical, experimental and modelling work, and enabled the scientific community to improve its current understanding of the fundamental heat transfer phenomena in boiling fluids and to develop more accurate tools for the prediction of two-phase cooling in nuclear systems. Data and insights gathered on the fundamental heat transfer processes associated with the behaviour of single bubbles enabled us to develop and apply more capable modelling tools for engineering simulation and to obtain reliable estimates of the heat transfer rates associated with the growth and departure of steam bubbles from heated surfaces. While results so far are promising, much work is still needed in terms of development of fundamental understanding of the physical processes and application of improved modelling capabilities to industrially relevant flows.

In this proposed research, clear prospects of a real life marketing scenario, by analyzing a price discount policy and variable demand, are derived. The proposed study presents a production model along with time-dependent and selling price related demand for decaying items. Items deteriorate over time, therefore, considering deterioration in this model makes it more acceptable to the present marketing situation. The concept of delay-in-payments is utilized in this inventory system. In this research, a retailer buys some products, enjoys constant credit-period offers which are provided by the supplier. This model depicts a price discount strategy which is based on purchasing cost to attract more consumers in any business industry. By using this strategy, any manufacturer or business may gain more profit in comparison to methods suggested by earlier literature. The average profit function of the inventory system is maximized analytically and also finds the selling-price per unit and duration of the inventory cycle optimally. A numerical example, along with a case study and their graphical representations, are incorporated to verify the optimality of this research very clearly. The findings of this research have maximized the average profit function more than the existing literature.

Human action recognition has turned into one of the most attractive and demanding fields of research in computer vision and pattern recognition for facilitating easy, smart, and comfortable ways of human-machine interaction. With the witnessing of massive improvements to research in recent years, several methods have been suggested for the discrimination of different types of human actions using color, depth, inertial, and skeleton information. Despite having several action identification methods using different modalities, classifying human actions using skeleton joints information in 3-dimensional space is still a challenging problem. In this paper, we conceive an efficacious method for action recognition using 3D skeleton data. First, large-scale 3D skeleton joints information was analyzed and accomplished some meaningful pre-processing. Then, a simple straight-forward deep convolutional neural network (DCNN) was designed for the classification of the desired actions in order to evaluate the effectiveness and embonpoint of the proposed system. We also conducted prior DCNN models such as ResNet18 and MobileNetV2, which outperform existing systems using human skeleton joints information.

Some of the most promising distributed recycling and additive manufacturing (DRAM) technical systems use fused particle fabrication (FPF) or fused granular fabrication (FGF), where compression screws force post-consumer waste plastic through a heated nozzle for direct 3D printing. To assist the technical evolution of these systems, this study provided the details of an invention for a low-cost, easily replicable open-source grinding machine for compression screw manufacturing. The system itself can be largely fabricated using FPF/FGF following the self-replicating rapid prototyper (RepRap) methodology. This grinding machine can be made from a cordless cut-off grinder and &lt, $155 in parts. The new invention is demonstrated to be able to cut custom screws with variable (i) channel depths, (ii) screw diameters, (iii) screw lengths, (iv) pitches, (v) abrasive disk thicknesses, (vi) handedness of the screws, (vii) and materials (three types of steel tested: 1045 steel, 1144 steel, and 416 stainless steel). The results show that the device is more than capable of replicating commercial screws as well as providing makers with a much greater flexibility to make custom screws. This invention enables the DRAM toolchain to become even more self-sufficient, which assists the goals of the circular economy.

In the present scenario for the development of the unmanned aerial vehicle (UAV), artificial intelligence plays an important role in path planning and obstacle detection. Due to different environments, it is always a task to achieve the proper moment for achieving the target goal while avoiding obstacles with minimum human interference. To achieve the goal with the avoidance of obstacles, individual optimization techniques with metaheuristic algorithms such as fuzzy, particle swarm optimization (PSO), etc. were implemented in various configurations. However, the optimal solution was not attained. Thus, in order to achieve an optimal solution, a hybrid model was developed by using the firefly algorithm and the fuzzy algorithm, establishing multiple features of the individual controller. The path and time optimization were achieved by a standalone controller and a hybrid firefly&ndash, fuzzy controller in different conditions, whereby the results of the controller were validated by simulation and experimental results, highlighting the advantages of the hybrid controller over the single controller.

Metal additive manufacturing (AM) has gained much attention in recent years due to its advantages including geometric freedom and design complexity, appropriate for a wide range of potential industrial applications. However, conventional metal AM methods have high-cost barriers due to the initial cost of the capital equipment, support, and maintenance, etc. This study presents a low-cost metal material extrusion technology as a prospective alternative to the production of metallic parts in additive manufacturing. The filaments used consist of copper, bronze, stainless steel, high carbon iron, and aluminum powders in a polylactic acid matrix. Using the proposed fabrication technology, test specimens were built by extruding metal/polymer composite filaments, which were then sintered in an open-air furnace to produce solid metallic parts. In this research, the mechanical and thermal properties of the built parts are examined using tensile tests, thermogravimetric, thermomechanical and microstructural analysis.

Recurring and increasing large-scale wildfires across the globe (e.g., Southern Europe, California, Australia), as a result of worsening climate conditions with record temperatures, drought, and strong winds, present a challenge to mankind. Early fire detection is crucial for a quick reaction and effective firefighting operations, minimizing the risk to human lives as well as the destruction of assets, infrastructures, forests, and wildlife. Usually, ground firefighting relies on human intervention and dangerous exposition to high temperatures and radiation levels, proving the need for mechanisms and techniques to remotely or autonomously detect and combat fire. This paper proposes an autonomous firefighting system built with a motorized water turret, narrow beam far infrared (FIR) sensors, and a micro-controller running novel algorithms and techniques. Experimental field results validated the technical approach, indicating that when a small fire front is within the field of view of the FIR sensor and within the range of the water jet, it is possible to provide an early alarm and even autonomously extinguish or delay the approaching fire front, increasing the chance for evacuation.

This paper synthesizes the design of an infeed cylindrical grinding system into a total system composed of the grinding mechanism and the grinding machine characteristics. The causalities between the grinding parameters and the machine structures are discussed, and the infeed grinding processes are analyzed as outputs that represent responses to the inputs. These relationships are integrated into a block diagram with closed-loop feedback. A novel model exhibiting practical parameters such as grinding speed, infeed rate and MRR (Material Removal Rate) is proposed. The analysis of the grinding system derived a critical factor, the &ldquo, grinding time contact,&rdquo, which governs the transient behaviors of process parameters such as forces and machine deflection. The process parameters during the infeed cycle including spark-out grinding were investigated, and the formulas required for the cycle design are presented. Furthermore, to improve accuracy and productivity, the features of the cycle design are described and procedures for controlling size error and roundness are discussed. Finally, the model was verified with infeed grinding tests applied to both the chuck-type cylindrical and centerless grinding methods.

Owing to the expensive applications of nanoparticles in engineering sciences, an admirable attention has been intended by researchers on this topic in recent years. The utilization of nanoparticles as asource of energy is intended much attention of investigators in recent decade. This novel attempt investigates the thermal properties of Casson nanofluid containing microorganisms induced by an oscillatory moving surface. The fundamental features of heat and mass phenomenon are inspected by utilizing the temperature-dependent viscosity. Buongiorno&rsquo, s mathematical model is used to report the famous Brownian motion and thermophoretic diffusion consequences. The flow problem characterizes the partial differential equations for which analytical solution has been computed with a convincible accuracy. The insight physical features are inspected with help of various curves. The physical significances of flow parameters is studied via various graphs.