Volume 22 (2022): Issue 1 (July 2022)

The Automatic Voltage Regulator (AVR) is necessary to keep the terminal voltage of a loaded alternator constant. It is widely used to increase the regulation and stability of synchronous alternators especially in bulk power plants where efficiency and stability is of paramount importance. The AVR is a feedback controller that varies the excitation of the alternator to support a constant output voltage by increasing or decreasing the excitation level of the alternator as the load varies. In this research, the transfer functions of the various stages of the AVR are decided for the purpose of the design of the Voltage Regulator. The performance of the AVR is decided by the basic no load and load test on the alternator. The results show that there was tremendous improvement in the terminal voltage of the alternator with the AVR and a significant drop in the terminal voltage of the alternator without the AVR.

In this article we aim to make an analysis of the evolution of security systems for smart homes and to present some effective solutions. Manufacturers are not developing smart devices from scratch, but are using existing solutions launched by large IT companies to help build smart home networks. The sensors are integrated in different places in homes, offices, equipment, sometimes even clothes, to detect and monitor the location, actions, necessary signs, room temperature and humidity levels of users properties. However, ensuring confidentiality and effective security is a major challenge for smart homes. The increased risk of data security and information leakage makes smart home security an important challenge that needs to be carefully considered.

This study examines the performance of the MPPT Proteus model. The high performance of this model was proposed for a photovoltaic system and tested using the most commonly known MPPT techniques. The proposed Proteus model is a simulator of a maximum power point tracking system for a photovoltaic panel connected to the DC-DC converter with digital control. The Proteus software performs simulation and implementation of the photovoltaic panel model based on a one-diode model and a two-diode model with high accuracy. Both photovoltaic panel models were validated by experimental measurements. Simulation results for tracking voltage, tracking current and tracking power show that this model performs satisfactorily. The theoretical evaluation confirms the high performance of the MPPT Proteus model, which offers a high degree of control and planning.

Currently, the market for the selling of petroleum products has reached a stage of development where it is almost impossible to satisfy all consumers with a single oil product, each category of consumers having their own expectations from the purchased product. Consequently, oil companies must consider the differences between consumer requirements and expectations when developing both their marketing mix and their marketing strategy. To achieve such a goal, they can adopt the strategy of dividing the market for petroleum products into specific groups, each including consumers with common characteristics and similar needs for certain goods and services. The action of finding the above-mentioned groups is called market segmentation. The segmentation of the market for petroleum products is the most important marketing tool, its role being that of helping the company find its place on the market.

Mobile telecommunication sites are an essential station in our technological life, used to allow the communication through mobiles and internet. Many telecommunication sites are installed in remote areas where the grid is not available. For this, hybrid renewable energy systems (HRES) are used to power the stations and integrate the remote areas with the world. This article aims to evaluate the performance of the existing HRES of the remote mobile telecommunication station of Bougaroun, Collo, Algeria -which consists of PV modules, batteries and diesel generator (DG)- and to develop it using a mathematical model to demonstrate the effect of deploying a wind turbine to supply more green energy, minimize the operation cost (fuel consumption and maintenance), and reduce the greenhouses emitted by the DG. Based on the wind data at the site location, the obtained results show a significant amount of output power that can be used to minimize the DG functionality.

The article’s main purpose is to analyse the effects of the “forced “digitalization process on the changes of the social attitudes appeared when the Covid 19 pandemic started. We will also outline efficient solutions to adapt to the new surrounding reality. The study aims to present a complete and objective analysis on the way the pandemic imposed not only behavioural and social changes, but also different visions at society level, about the imminent need for the digitalization process.

The paper aims to analyse a fiber optic link by using fiber optics (FT1000EMT, FT800UMT, FT200UMT, FT1500UMT), transmitters (M9-A64-0300, VCSEL-1060-SM, TUVE-1060-T-TO) and receivers (SRP00294, LDPF XXXX), using Octave.

Distribution of active and reactive power between consumers raises the problem of participation of each power station in supply of loads and determining flows of power from each generator trough branches of an electric power network. Interest of this problem mainly is chosen by the development of open access market in power systems. In this paper a method is reviewed of determination of settlement factors, which is based on finding the trace in oriented graph, and allows, with the number of cycles equal with the number of generator nodes, determine the part of active power, which flow from each generator through branches of electric network to load node.

This paper presents a preliminary version of case study for propagation process using Matrix of Partial Derivatives of the State Vector (Mpdx) Method associated to second order Partial Differential Equations with two Independent Variables and Approximating Solutions. Considering a thermally insulated layer of a specific thickness exposed on the upper part to a constant overtemperature with a uniform distribution over the entire heat transfer surface, using numerical modeling are emphasized some interpretation variants for evolution of processed signals for possible applications.

This paper presents a case study of interdisciplinary subjects, more precisely the AGILE SCRUM specific to software development applied in agricultural processes to increase the productivity, maximize the profit and to emphasize the benefits of AGILE methodology which is suitable in every field of industry. Starting with theoretical aspects about Agile project management approach and philosophy, including values and principles, continuing with SCRUM framework, is emphasized the applicability of the method in various fields of industry, including agriculture.

This article presents a desktop application which purpose is to help ethnomusicologists, music specialists and researchers in managing better the possible results of a field folklore investigation. Because a field investigation in ethnomusicology, ethnology and ethnography domain generates a huge video or audio material, it can be extremely difficult and time spending for specialists to handle with it, to extract all the information needed, to organize and to make a specialized analysis for a report or for a specific study in a traditional manner. At the same time, computer programming and database practice can have a major impact on musical and literary analysis of folklore songs, especially when they are put together within an application. The purpose of this article is to suggest and to describe such a computer application.

The design of an optical system sets up the knowledge of the limitations dictated by the losses and dispersion in the optical fiber (in direct connection with the wavelength used) for a point-to-point connection. Except for short links used in local area networks, attenuation losses play a significant role in system design. The paper aims to analyse a fiber connection in terms of the best communication distance using Octave and Packet Tracer.