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The power quality of distributed power generation systems is a growing, challenging, and fascinating field in modern times. Power quality refers to assessing and maintaining optimal power quality during generation, transmission, and distribution. The power quality gets degraded due to voltage sag/swell, flickers, voltage spikes, harmonic distortions, etc. These issues are usually caused by non-linear loads in welding machines, arc furnaces, and other heavy types of machinery. In the present study, the Distribution Static Compensator (D-STATCOM) helped in compensating the harmonics and the reactive power demanded by the non-linear loads. The reference current for D-STATCOM is derived using the Synchronous Reference Frame Theory (SRFT). The Total Harmonic Distortion (THD) percentage is calculated by designing the simulation block diagrams in the Matlab/Simulink. As a result, the source's power factor (PF) is improved, and the Total Harmonic Distortion in the source currents is analyzed as 4.76%, its considered satisfactory as per the IEEE-519 standard. [ABSTRACT FROM AUTHOR]

Purpose: Literature is replete with research on expectations of customers from restaurants they visit and resulting effect on overall restaurant business. But after the onslaught caused by SARS-CoV-2 pandemic, customer priorities have changed a lot. In the current study, the researchers intend to ascertain the factors affecting customer expectations and also their impact on the satisfaction of restaurant customers and their intention to visit the restaurants again after Covid-19 lockdown relaxation. Design/methodology/approach: Herein the workers studied quantitatively the various factors on which expectations of the customers are dependent in the current situation. A sample size of 300 customers from Chandigarh Tricity was taken who availed restaurants' services when they reopened during lockdown relaxation. Findings: Three relevant factors were observed which were significant during the pandemic period namely hygiene, health and safety. Regression analysis was conducted on these three factors to ascertain the connection between customer satisfaction and their revisit intention. The hygiene factor displayed the highest impact out of the given variables on the customer expectation and revisit intention after the Covid-19 crisis. Keeping this in mind, it is recommended to adopt new and emerging technologies like PMS, QR Code Menus, Robots serving food etc. that will increase automation and reduce human touch. Implications: Since Covid-19 is a highly communicable disease, these three factors have to be taken care of by the restaurant management in order to get a higher level of satisfaction of the customer and revisit intention thus increasing business. Originality: The study was conducted during the Covid-19 pandemic when restaurants started reopening after government relaxed lockdown to find out customer expectations so that restaurant business can come to normal. [ABSTRACT FROM AUTHOR]

The Pandemic (Covid-19) deeply impacted the Hospitality and Tourism industry across the country. Its effect disrupted human lives and pushed the country to an economic slowdown. This Pandemic brought fear of travel and dining out, on every person be it a domestic or an international traveller. Lockdowns and intra state travel ban, and the fear of being quarantined took its toll on Hospitality and Tourism Industry. In This paper researchers are making an effort to find out the extent to which this deadly Virus (COVID-19) has impacted the Travel and Tourism industry in India and also explains how our tourism sector shall cope with this extraordinary circumstance, and establish Management and Recovery strategies. Pre COVID-19, Hotels and Restaurants were relying on various techniques and marketing skills for selling Food and Beverage, but post COVID-19 the entire scenario changed and those skills went redundant. Reinventing and innovative use of technology is the call of the hour to breathe life into the Hospitality and Tourism Industry. This research paper recommends that we need to be proactive in planning as per the guests' perceptions of the hygiene and cleanliness in hotels as these will be the new normal and deciding factors in the Guests mind to visit Hospitality establishments. Additionally, a detailed study is required to adopt necessary healthcare facilities for hotel guests and employees. [ABSTRACT FROM AUTHOR]

One of the most effective techniques for determining the best choice among the several is to use a fuzzy TOPSIS. This paper proposes a novel intuitionistic fuzzy entropy measure to deal with a MCDM problem by using fuzzy TOPSIS. To express rating of each option and weighting of each criteria, this method uses an intuitionistic fuzzy number. An actual example has given to show how the fuzzy TOPSIS approach may utilized to address a MCDM problem in which we compare the three universities Guru Nanak Dev University; Panjab University and Punjabi University while choosing on the most desired choice, the decision maker uses the seven criterion by using real data from https://naac.gov.in. At the last, we show the distinction between the suggested fuzzy TOPSIS approach and the classic fuzzy approach. The suggested fuzzy TOPSIS method uses intuitionistic fuzzy numbers to introduce objective entropy weights into an intuitionistic fuzzy environment, while the classic fuzzy TOPSIS method uses intuitionistic fuzzy numbers to introduce criterion weights into a fuzzy environment. This shows that the alternatives' closeness coefficient values are quantitative and change depending on the criteria, and can used to show the degree to which one alternative is better than the other one. [ABSTRACT FROM AUTHOR]

Bearing is a critical component in any machine as most of failures occurring in rotating machinery are due to bearings. Although bearing is suitably chosen for a particular application but still for some specific applications like railways and aircrafts, world-renowned manufactures like SKF and NBC prefer to do coating on it to improve the properties hence remaining useful life (RUL). Properties like roughness, hardness, wear resistance could be improved as per the requirement of the practical use. In this study, different coatings on the bearing are analysed with their respective grade of tribological properties from the available literature. Firstly, the relation of tribological and mechanical properties of the coatings was co-related with the practical usage of the bearing. Thereafter, the degradation in the properties of bearing coatings over the usage of time was discussed along with conventional techniques available for the measurement of properties. It was observed that the conventional techniques were having number of challenges in measurement of properties as bearing needed to be dismantled or even damaged. To overcome this challenge vibration-based techniques were finally proposed to detect these changes in the properties because of their sensitivity to detect even small changes in the vibration signature. It is also suggested that if vibrational based techniques could be implemented in detecting the property changes, then the remaining useful life can be predicted more accurately. [ABSTRACT FROM AUTHOR]

To In the 21st century, the automotive industry is booming. A major problem with internal combustion engines (I.C.) is the noise coming from the exhaust system. This noise is very harmful for human health according to different researchers. It is for this reason that mufflers are used to reduce the noise produced. Although mufflers are not designed to perform any of the main output functions, they are included within the I.C. engines. It is designed as a sound protection device that reduces engine pressure. But mufflers need structure and geometry, if you think the physics behind it are very confusing. The muffler design developed into a repetitive process with trial and error. Recent research in this area has made it possible to do so through analytical and experimental methods. In this paper, three dissimilar models of mufflers are reflected for study. Aerodynamic performance parameters of this mufflers are determined through CFD analysis and it is performed in ANSYS software. It was witnessed that the 3rd model achieves the highest amount of pressure drop i.e. around 15-22% more than the 1st model and 2nd model, whereas 2nd model produces around 1-5 % more than model 1 at different inlet velocity. From this CFD analysis it could be decided that the 3rd model is the best optimized muffler for usage in automotive vehicle. [ABSTRACT FROM AUTHOR]

The rolling element bearings are the most essential components of machinery. Most of the rotating machinery failures are generally linked to bearing failures; hence conditions monitoring using vibration analysis and fault diagnosis of these bearings are of major significance in industries and also help for making the maintenance strategies. This paper presents a wavelet packet transform (WPT) based methodology for detecting the crack propagation of taper roller bearing. In order to extract relevant information from raw data db03 and shannon based wavelets were used and entropy was calculated. The vibration signal captured from the bearing having outer race defect was decomposed using Wavelets Packet. The results show that the energy coefficients of wavelet packet nodes are affected by the crack propagation rate. This work establishes the applicability of the wavelet packet node energy coefficients for analyzing the crack propagation rate and can be used as a criterion expressing the condition of a bearing. It was observed that till 180 hours no change was happened in any of the node no edge breakage has happened till this hour. After 180 hours the nodes shows rise in range of the signal for 200 hours signal and out of all the nodes (3,5) node has shown maximum rise in the range from about 100 to 400 and edge breakage has also identified physically. The experimental findings show that the proposed method is effective in identifying crack propagation rate of roller element bearing [ABSTRACT FROM AUTHOR]

Day by day automotive vehicle has become the basic need of human life. Due to the increase in number of automotive vehicles, the noise produce by the exhaust system of these vehicles is also increasing. This large noise greatly affects the human health and causes many diseases. So reducing the exhaust noise is the main area of concern. Muffler is one such acoustic filter which could be implemented for reducing the exhaust noise. Reactive muffler and dissipative muffler are the basic types of muffler. Transmission loss (TL) is the main performance parameter which determines the amount of noise reduced by the muffler. This performance parameter could be determined through acoustic analysis. In this study pressure acoustic analysis is performed for obtaining an optimized reactive muffler. The effect of variation in length of chambers, implementation of baffles and changing the hole position in baffles are the parameters considered for study. From the study, it was initially observed that elliptical chamber type muffler produces more transmission loss than a circular chamber type muffler. Finally, through acoustic analysis it was observed that an optimized muffler was obtained which is having maximum transmission loss of 123 dB as compared to next maximum transmission loss of 110 dB. Further it was observed that the sound pressure level also reduced from 90 dB at the inlet to 20 dB at the exit. These results justified that the optimized muffler is one of the most suitable muffler for use in automotive vehicles. [ABSTRACT FROM AUTHOR]

Multiple Criteria Decision Making (MCDM) is a decision-making method in which we decide the right decision from a range of viable options based on the comparative or context of specific of a defined system of interrelated or impartial parameters. By giving preferred evidence in the form of an actual real number or a range, a suitable solution may be selected. Therefore, given ambiguous or inaccurate facts, desire info in actual life could be analyzed directly. In certain instances, uncertainty is generated by creators who are ambiguous or inaccurate. Such feature provided researchers with a strong incentive to apply MCDM methods in an uncertain environment. In recent times, TOPSIS is often known about MCDM in several areas. The fuzzy TOPSIS (technique for order preference by similarity to ideal solution) approach and several basic principles are discussed in this paper. The major aim of this paper is to create a novel intuitionistic fuzzy set decision-making method based on a novel fuzzy entropy measure. To begin, create a novel intuitionistic fuzzy entropy measure as well as innovative weighting techniques for intuitionistic multi-criterion decision making by using the attribute values based mostly on the fuzzy based measure. In addition, it develops an intuitionistic fuzzy TOPSIS method for ranking options, and a practical example is provided in which we compare the four universities LPU, Amity University, Chitkara University, and Chandigarh University for the purpose of selecting the best one for admission by using the real data. [ABSTRACT FROM AUTHOR]

The present paper is obligated to develop a numerical technique for solving higher order ordinary differential equation containing initial conditions. The efficiency of Runge-Kutta method for an implicit function consisting of sixth order ordinary differential equation denoted as RKSD is analyzed. The three stage seventh order Runge-Kutta methods (RKSD7) depending upon order conditions have been constructed and derived for RKSD. Numerical equations and results are presented in this paper for illustrating the Zero-Stability of RKSD7 through relevant set of problems. [ABSTRACT FROM AUTHOR]

The reactions involving fusion-fission of compound nuclei 244,247Cm* formed in low energy heavy ion collisions of 12,15C projectiles with actinide target 232Th have been investigated within dynamical cluster-decay model (DCM). We have probed the effects of transition from a paired to an unpaired valence neutron or halo nature of projectile (15C) on the fusion-fission cross sections (σFF) of decay of compound nuclei (CN) 244,247Cm*, formed in these reactions. The calculations are performed using spherical shape of nuclei at touching configuration at near-barrier energies (Ec.m.= 68-70 MeV) where experimental data is already available. The dynamical behaviour of these reactions is explored via fragmentation potential (V), preformation probability (P0), summed up preformation probability over angular momenta (ℓ) values (ΣP0) and penetrability (P) for fusion-fission fragments (FF) having mass numbers (ACN/2) ±20. It is observed that the overall pattern of fragmentation potential, V(MeV) at different ℓ values remains unaffected, but the potential energy surface (PES) for FF fragments show peculiar behavior with increase in mass of CN. These characteristics of the FF fragments are presented in terms of preformation probability (P0), explicitly. The effect of halo configuration of projectile is evident in the summed-up preformation probabilities (ΣP0) of various FF fragments, which means that the relevant structure information is duly explored. The DCM calculated, normalized values, of σFF are found to be consistent with the experimental data. The observation of enhancement in the magnitude of σFF for neutron-rich matter reveals the modification of nuclear behaviour, as we move towards region close to the drip line. [ABSTRACT FROM AUTHOR]

We investigate the low energy 20O+12C reaction at Ec.m. = 9.29 MeV populating the 32Si* nuclear system within dynamical cluster-decay model (DCM) and bring about the role of temperature (T) dependent binding energies in the reaction dynamics. T-dependent binding energies are one of the crucial ingredients of DCM used to calculate the fragmentation potential and hence the fusion cross-section. The inculcation of T-dependent binding energies from microscopic relativistic mean field (RMF) theory in comparison to that from Davidson formula, leads to considerable change in the fragmentation profile, preformation probability of different fragments. Subsequently, it affects the contribution of individual channel in the fusion cross-section associated with light charged particles (LCP) emission. It is noted that the statistical evapOR model under predicts the LCP cross-section σLCP. On the other hand, DCM calculated σLCP is in nice agreement with experimental data for both cases of T-dependent binding energies although contribution of 3H and 4He channels in σLCP changes significantly for both cases. [ABSTRACT FROM AUTHOR]

Within the Strutinsky renormalization procedure temperature dependence of binding energies of nuclei has been observed, where the binding energy comprises of the macroscopic and microscopic part i.e. the liquid drop energy VLDM and the shell correction (δU), respectively. It is observed that δU (particularly at energies ≤ 1.5 MeV) along with the VLDM plays a crucial role to give proper understanding of the nuclear reaction dynamics at the given temperatures of the composite nuclei formed in the low energy heavy ion collisions, within the dynamical cluster decay model of Gupta and Collaborators. We observe that effect of temperature on various binding energy terms of the formula is varied at different temperatures (0 - 4 MeV). This variation is guided by the temperature dependence of various energy coefficients obtained by Davidson et. al., which eventually affects the binding energy per nucleon (B.E./A) curve quite significantly. We find that values of B.E./A show consistent increasing trend up to T = 1 MeV, attributing it to the peculiar behavior of the surface energy term, and for higher temperature (say 2 - 4 MeV), it is showing downward trend particularly for nuclei with A ∼ 10-150. While for heavier nuclei, the values of B.E./A start increasing beyond T = 2 MeV, due to the asymmetry energy term. [ABSTRACT FROM AUTHOR]

The coatings on materials have contributed significantly in engineering applications and its attributes could be studied unconventionally through vibration signatures. In this work, three different bearings (NBC6205) are coated with Zn3(PO4)2, copper and nickel, all deposited by electroplating. The results obtained after measurements of surface finish of the coated surface shows that the surface finish of zinc phosphate is better than copper and surface texture of copper is smoother than nickel. Under load, all three bearings are made to run at three different rpm and their vibrational signals are being acquired. The statistical parameters are calculated for the acquired signals for different coatings at different rpm and results are compared with reference to the properties of coating. It is observed that bearing with zinc phosphate coating is giving less values of statistical moment, because Zn3(PO4)2 has better surface finish followed by copper and nickel. Further, analysis is done to get spectral contents of the acquired signals by taking Fast Fourier transform (FFT), where it is found RMS, standard deviation (SD), Logarithmic energy (LE) and Shannon Entropy (SE) are showing rising trend compare to other parameters of spectral contents. Due to the low value of spectral content, it is clear that signal is less harsh in zinc phosphate coating, which further reflects its better surface finish level. Then sensitivity index is calculated so as to get most sensitive parameter among the responded parameters. From results, it is found that SE of spectral contents is the most sensitive parameter, which is showing considerable deviation and could be proposed as reference to reveal the distinct values of surface finish. [ABSTRACT FROM AUTHOR]

There has been a crucial demand to synthesize graphitic carbon at an economical rate. In this respect, renewable biomass resources such as rice husk, rice straw, wheat straw, corn straw, animal manures, etc. serve as a quite eco-friendly, low-cost source of carbon. In the present study, the valuable graphitic carbon is synthesized through the torrefaction of rice straw, which includes the slow heating of the raw material in an inert environment to a temperature of approximately 300 °C. FESEM, HRTEM, and XRD were utilized to confirm its presence and determine its surface and internal morphology. Apart from spherical carbon structures, some bundles of CNTs have also been observed in the SEM and TEM images. [ABSTRACT FROM AUTHOR]

The purpose of this work is to study the dynamics of competing α and 208Pb daughter cluster radioactive decays using the preformed cluster decay model (PCM), within the collective clusterization approach of Quantum Mechanical Fragmentation Theory (QMFT). The QMFT based fragmentation potential comprises of binding energy (B.E) (which is the sum of liquid drop energy (VLDM), based on semi empirical mass formula of Seeger and shell corrections (δU) given by Myers and Swiatecki), Coulomb potential (VC) and nuclear proximity potential (VP) of the cluster and daughter nuclei in the ground state decay of the radioactive parent nuclei. To explore the competing aspects of α and 208Pb daughter cluster radioactivities, we have chosen 222Ra, 226Th, 228Th, 231Pa, 230U and 232U parent nuclei. The crucial role played by shell closure effects is demonstrated in minimized values of fragmentation potential for cluster accompanied by doubly-magic 208Pb daughter nucleus in comparison to neighboring fragments. The higher values of preformation probabilities, P0 of these clusters further reveal significance of nuclear structure in the cluster radioactivity process. We have calculated the half-lives via fragmentation potential, preformation probability, scattering potential for spherical case, of chosen nuclei, and then compared with the given experimental data. From the comparison of α cluster and 208Pb daughter decays, we see that the former is heavily dominating with larger values of P0 in comparison to the later as evident from the experimentally observed high count rate of α cluster in such decays. However, the penetrability for both types of decays is almost similar. The experimental data and PCM calculated results are in fair comparison for all the chosen cases. [ABSTRACT FROM AUTHOR]

The non-stoichiometric combustion of hydrocarbon fuels lead to the significant soot emission, the concentration of which varies with air-fuel ratio and mass flow rates of air and fuel. By effective utilization of computational fluid dynamics tool, it is easy to predict the various process parameters such as temperature distribution inside the flame, optimum air to fuel ratio and reactant and product concentrations inside the flame. This paper present the numerical analysis of liquefied petroleum gas (LPG) fuelled diffusion flame to investigate the influence of air-fuel velocity ratio on flame temperature and soot mass fraction. Simulation has been carried out at fixed fuel flow rate and varied air flow rate. The observations indicate that the peak flame temperature and mass fraction of soot increases with decrease in the air flow rate. This soot can then be purified to get carbon nanoparticles. [ABSTRACT FROM AUTHOR]

Graphene is attractive two-dimensional (2D) carbon nanomaterial has excellent mechanical flexibility, superior electrical conductivity and high thermal/chemical stability. Many reports have been available on applications of graphene in different fields. Present work describes an easy way to prepare graphene embedded conducting Polyvinylidenedifluoride (PVDF) membrane pore size 0.22 μm. In this work graphene oxide (GO) was prepared by modified hummer method and then graphene oxide was reduced by using ascorbic acid. Graphene-PVDF flexible nanohybrid film was prepared. The film was characterized by field emission scanning electron microscopy, X-ray Diffraction Spectroscopy (XRD) and Fourier transform infrared spectroscopy. FESEM, XRD and FTIR results ascertained the presence of graphene on polymer membrane. Supercapacitor application of the PVDF-graphene conductive paper was investigated by using cyclic voltammetry (CV). [ABSTRACT FROM AUTHOR]

Laser detonation of secondary explosives is a great field of interest from past half of the decade. This present work is one step more in the direction of development of laser based detonator. Here in present case, PETN explosive has been mixed with gold nano rods with rigorous Sonication and stirring method. To process a free flow composition of energetic material, for the very first time freeze drying technique has been utilized for energetic material (PETN) and gold nano rods composition. Scanning electron microscope (SEM) images have confirmed the formulation of better composition of gold nanoparticles with PETN explosive whereas energy dispersive x-rayspectroscopy (EDS) graphs have supported the SEM images with elemental confirmation of presence of gold inside the crystal structure of PETN, also the absorption studies of the gold nanoparticles and PETN energetic material reveals that the absorption spectrum Laser initiation experiments done with laser diode 980nm in CW mode .Experimentally, it has been observed that the laser power of 4 Watt is sufficient to ignite successfully this energetic composition. [ABSTRACT FROM AUTHOR]