Advanced Aspects of Engineering Research Vol.12

The rapid improvement in efficiency of perovskite solar cells has made them the key to future developments in photovoltaics and their properties are of great interest to the academic community. Perovskites exhibit a host of intriguing properties, such as ferroelectricity, superconductivity, magnetoresistance, birefringence and piezoelectricity, due to their unique crystal structure. In comparison, perovskite solar cell performance has improved from 3.1 percent in 2009 to 24.4 percent in 2019. As a vast number of elements can be assembled to form perovskite structures, the physical, optical and electrical properties of perovskite can be engineered and optimized selectively. It is possible to access the previously unknown structural properties, opto-electronic properties and operating parameters of these materials with high precision through theoretical and analytical modeling. This paper seeks to describe a few abilities of DFT hybrid functionals to investigate the electronic, structural and optical properties of compounds that constitute different layers of a perovskite solar cell using software packages such as VASP, WIEN2k etc. The effect of doping on the electronic properties of different layers of perovskite solar cells, including band gap, visible light absorption, relaxation time of holes and electrons using DFT, is also examined in this paper which in turn defines the optimum separation of charge. The consequence of adding an intermediate band gap in the perovskite structure using G₀W₀+SOC approach-based DFT methods is also discussed here. A study on the impact of different intrinsic defects present in perovskite structures using VASP or WIEN2k package with DFT calculations is also discussed. The importance of modeling the interfaces of different layers of perovskite solar cells with DFT packages is explored with the aid of selected material examples and representative interfaces.

In this work Spectral feature MFCC is considered for high accuracy, for Prosody feature Pitch is considered and concatenating with other two different features Cepstrum and DWT and this combination is called as Emotion- Specific Feature Set. A remarkable study is being done in the current years for improving human machine interaction on Speech Emotion Recognition. Speech contains a wealth of details about the Speaker's age, gender, and emotional condition.The challenging task of recognising a single emotion from a speaker is known as emotion recognition. The database under consideration is Telugu-Database, which is prompted by two male and female speakers and includes four emotions: happy, angry, sad, and neutral.To identify the corresponding emotion, different combinations of features are used, and these features are referred to as Emotion-specific features. The rate of combination identification is improved when these features are taken into account.The function information is extracted using the features DWT, Cepstrum, MFCC, and Pitch.After feature extraction, a back-propagation neural network algorithm is used to classify the data, and the results are then evaluated. The study concluded that by increasing number of nodes in the network and number of iterations the recognition rate is above 90%, the combinations of feature sets will give better emotion recognition rate than individual feature sets and the feature set combination DWT+Pitch+Cepstrum produced the individual emotion recognition rate above 95%.

The administration dispatches totally different aggressive comes trying to form the state additional prosperous, nevertheless what they bomb is in fruitful execution and coming back to recipients. the basic rationalization for this issue is that the absence of attentiveness among rustic people. This chapter is to allow a solution for this newsless circumstance. Through this framework the country understudies are educated such they will become at home with concerning what ar the various plans that ar outfitted by the administration and what ar the plans they're qualified for. On the off probability that the country understudies came to understand and acquire conscious of the apparent multitude of legislative plans gave by the govt. of India for the govt. help of the provincial understudies, at that time their life would venture into next level. Initially this framework can investigate the accessible government plans within the instructive for the govt. help of country understudies. Next, the understudy's data ((i.e.) name, age, station, occupation, annualincome.etc) ar accumulated. At that time; each the datasets ar brought into the Eunectes murinus Navigator. At that point, investigation and grouping addicted to networks (SC, ST, BC and MBC) of the understudies and therefore the plans ar performed. At that time utilizing the forecast calculations (Naïve Bayes, Random Forest and Support Vector Machine (SVM)) what ar typically the plans the particular understudy is qualified for ar anticipated. AN investigation is formed on the proficiency of the 3 calculations. The truth of the 3 calculations is poor down and therefore the effective calculation that creates the end result with most elevated preciseness is finally accustomed play out the forecast of the plans that a particular understudy is qualified for. At long last, the anticipated plans anticipated utilizing the foremost elevated effective calculation among the 3 calculations are gotten back to the understudies. Hence, through this endeavor the country understudies can return to consider totally different recipient plans gave by government and that they will use those plans for the advance of the country environmental factors

Nowadays, the health-care system is structured around creativity.

The key aim is to bring together a consistent patient inspection structure so that therapeutic services specialists can track patients who are also injured or carry out their everyday activities. This method is becoming increasingly beneficial to the elderly. By using Heartbeat Monitoring, it avoids additional time rates. We have some experience with electrocardiogram (ECG) estimation and pulse testing. Our system is designed to follow a patient's physiological sequence in order to determine when she or he feels most at comfort. The patient is transported in equipment with sensors and telephone applications; the sensors will sense the patient's essential sign and imperative indication, and this information will be transferred to the phone via Bluetooth/Wi-Fi. It also sends an instant message with an alert about the patient's essential well-being.  These information findings can be saved in a database that can be retrieved from a remote location if a crisis occurs legitimately. Sensors, a data acquisition facility, a microcontroller, and programming make up the majority of the system. Our framework checks, displays, and summarises the patient's body temperature, heart rate, muscles, blood glucose level, ECG information, and pulse level. This paper can play a critical role in saving a patient's life during a crisis.

The method of calculating the bending moment and curvature in the plastic zone of elastoplastic measurement of the carcass of the tractor cabin and on the basis of the strength characteristics of the carcass for the new cabin cotton-growing tractors of the class 1.4 is defined in the article.

The gamified e-learning approach has been widely used as a learning and teaching strategy, particularly in higher education.This strategy has been successfully used to engage, motivate and enhance learning performances. However, learners or students react differently to game designs and game mechanics depending on the subject area that a particular gamified application though there are several studies shows that gamification enhances motivation.In this paper, we designed and implemented a specific learning model for the gamified digital logic gates or LogIO. Thus, thirty (30) learners evaluated and we determined how do game design elements affect learners in terms of motivation, performance and learning experience.The main results of this study showed that learners agreed that the motivation level and usability of LogIO have a weighted mean of 4.48 and 4.49 respectively while performance and learning experience level has 81% during the utilization of the gamified mobile application.These results support the significance and relevance of adapting particular design elements for gamified digital logic gates to enhance motivation, performance and learning experience.

To reduce the total cost of power generation, power grid networks are becoming more integrated for the purpose of power transmission. With insufficient control, power systems become more difficult to operate and less secure. The economics of alternating current power transmission have always compelled planners to transmit as much power as possible through a given transmission line. Many networks have crowded smaller and thermally limited lines, while other higher capacity lines run well below their thermal maximum. When series capacitors are used in higher voltage cables, power can be transferred from overloaded lines, maximising the use of the existing line and supplementing the power system's performance. The aim of this paper is to demonstrate efficient line network utilisation for maximum power flow through the intended line with series capacitor compensation using a three-line meshed power system network with different thermal line limits. The simulations using the PowerWorld simulator show that adding a series capacitor increases the power transfer through the line before it reaches its thermal limit.

In developing countries such as Nigeria, there are significant problems with a shortage of affordable housing for low-income earners. The high cost of traditional building materials has been identified as one of the major factors driving up construction costs in recent years.  However, in the present day situation, incorporating green building materials that are appropriate and sustainable for building construction would offer excellent solutions for overcoming high construction costs. The surveying instrument was created and distributed to building professionals who are members of various professional bodies in the building sector. In north-central Nigeria, the research was conducted on all the available green materials. Surveyed instrument was prepared and distributed to building professional experts that are registered member of various professional bodies in the building sector. The extensive literature review and survey of relevant GM pinpoints various green materials and reveals that the adoption of GMs can result to lower cost of operation since they typically require little or no further process before being used for construction works. Throughout the north-central sector, 400 questionnaires were distributed. For the data analysis, 350 completed questionnaires were used.The study was analysed and a model was developed using the Analysis of Moments (AMOS) software and the structural equation model (SEM). The findings reveal that earth bricks, stone/rocks, timber, bamboo, thatches, straw fibre, and rice husk are all viable green building materials.

As a result, low-cost housing units would result from the use and incorporation of green materials in building construction.

The influence of the individual equiaxed and columnar cast structure on the evolution of texture during thermo-mechanical processes (TMP) was investigated using the electron backscatter diffraction (EBSD) technique. In this study, the effect of the individual IECS versus ICCS on texture evolution during rolling and annealing process was investigated. The recrystallization texture after cold working and annealing was then related to mechanical properties of the initial cast structures. It was found that the initial equiaxed cast structure exhibited a homogenous fiber texture while the columnar developed an inhomogeneous texture with the predominance of both the Goss and fiber textures. While texture has a significant influence on surface smoothness of the drawn product, it was found that it did not significantly affect the yield strength and ultimate tensile strength (UTS), but marginally affected the elongation i.e. it was found to be slighted higher for the equiaxed than the columnar cast structure measured parallel to the rolling direction (RD).

Though fly ash in South Africa has mainly been utilized in the construction industry, a large portion of it is still discarded. Production of glass-ceramic composites through fly ash devitrification has gradually become one of the applications being examined internationally. This study reports the investigation of producing glass-ceramic composites from fly ash and varying quantities of beverage waste glass and magnesium oxide as main raw materials. Glasses were obtained by melting fly ash and its additives using an arc furnace. Based on their behaviour when subjected to differential thermal analysis, the glasses were then crystallised through a double-staged thermal treatment to form glass-ceramic composites. The composition and behaviour of the glass-ceramic composites were investigated using X-ray diffraction, Scanning Electron Microscopy, mechanical and chemical assessments. The crystal content in the glass-ceramic composites increased as the magnesium oxide content was increased. The desired diopside phase decreased with an increased magnesium oxide content and ultimately resulted in the formation of forsterite and anorthite as the major and second major phases respectively. The glass-ceramic composites with lesser amounts of magnesium oxide were chemically and thermally resistant and they also demonstrated high cold compressive strength.

A specific SFSWH system for domestic hot water is proposed in Kovilpatti, Tamilnadu, 9°10'N 77°52'E. The results were clarified using parallel flow solar water heaters as a contrast after this SFSWH device was successfully simulated in TRNSYS Software. To begin, a complete model of a spiral flow flat plate collector is created in TRNSYS software, accounting for heat transfer, outlet temperature, and performance. This model is then theoretically compared to a parallel flow flat plate collector using the TRNSYS simulation programme. With the aid of NASA surface meteorology and solar energy year readings, as well as ISRO's solar calculator application, the SFSWH device performs a role relative to Kovilpatti, Tamilnadu, India. An experimental setup was done at Kovilpatti to prove the accuracy of the TRNSYS model of the SFSWH, and necessary results were obtained under Kovilpatti weather conditions. The validation of this SFSWH TRNSYS model simulation programme is completed by comparing the expected software results with the original results. The SFSWH TRNSYS model result shows that the SFSWH performs better than a traditional parallel flow water heater. As a consequence, the TRNSYS model is dependable, and it alternates the experimentation.

The problem of the alkali-silica reaction is one of the top problems in the modern concrete science. The appearance of such reaction in the hardened cement and concrete stone results in the crack appearance and destruction of material. The present study discloses the results of a study on structure formation processes in the interfacial transition zone “cement stone - aggregate” of the alkali-activated cement concretes. The results indicate the influence of Al₂O₃ content in the cement composition on alkali-silica reaction gain in alkali activated materials. Introduction of additional source of Al into the system leads to the constructive gain of the alkali-silica reaction process in the system. This constructive effect is caused by incorporating the corrosion products into alkaline alumina silicate compounds, thus retarding the internal corrosion of the concrete and providing the higher durability even in case of alkali-activated cements and alkali-susceptible aggregates with relatively high alkali content. Also there are shown variations of the pH values in different alkali activated cement systems depending from type of alkaline component and additional source of alumina.

Sol gel co precipitation and commercial mixing methods were used to make Nd,Cr,Ce:YAG Nano powders. Both powders were calcined at temperatures ranging from 900 to 1100°C. The crystals were then vacuum sintered for 8 to 20 hours at temperatures ranging from 1700 to 1750°C. SEM, EDAX, TEM, and TGA-DSC were used to investigate the impact of calcinations and sintering on the Nano-structure. The optical properties of crystals were analysed using UV spectroscopy.The SEM morphology revealed a soft powder with a spherical shape and particle size >90 nm, which was also visible in the TEM images.After sintering, the crystal displayed a high degree of compactness, with mainly one step and very few and tiny pores. The EDX analysis showed the %Y/Al= 0.6 near the theoretical value and the XRD sharp peak confirmed YAG formation. The TGA-DSC curve revealed the crystal's thermal behavior, with a temperature of formation of nearly 750°C for YAG. UV spectroscopy was used to investigate the optical property. Around 300 nm, the absorbance maxima at 0.5 appeared, showing a band region with several peaks for Nd,Cr,Ce:YAG.

An approach for recovery of used seawater After reacting magnesium metal with citric acid to produce hydrogen gas and precipitating magnesium as magnesium gluconate, the remaining water is desalinated using the reverse osmosis technique. Magnesium gluconate was prepared as a medication product under ordinary conditions and is soluble in water.A spiral wound Reversed “Osmosis” commercial membrane module was used in prototype unit. Different concentrations of remediated seawater were mixed to create the necessary water salinities for spinach irrigation in rural areas with no other source of water. Irrigation results showed that 1000 ppm, 650 ppm, and 350 ppm almost gave the best treatments with fresh, dry, weight, and NPK when compared to 150 and 200 ml.