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Study on Factors Influencing the Strong Chromatic Index of Graphs derived from Path Graphs, Star Graphs, and Cycle Graphs
No full textGraph coloring is a major research area in Graph Theory that has a rich collection of research articles contributed by mathematicians across the world. This thesis focuses on a specific type of Graph coloring where the edges of a graph are colored by a principle called strong edge-coloring. There have been numerous research articles published on the least number of colors required to define such a coloring for a given graph G. This least number, χ′s (G), is called as the strong chromatic index of a graph G. Though conjectures stated as early as 1989 remain unsolved, there have been many results proving the conjecture for particular families of graphs. Other significant contributions have established upper bounds for χ′s (G) for specific classes of graphs such as planar graphs, sparse graphs, and some specific bipartite graphs.
A fair share of the articles published in this area of research includes significant applications in the field of wireless sensor networks. In particular, congestion in wireless data transfer and two types of interferences in wireless communication networks can be avoided by modeling and analyzing these networks using graphs. In particular, the problem of assigning interference-free frequencies to a wireless sensor network is equivalent to the problem of coloring the edges of a graph by the principle of strong edge-coloring. Further, the design of a placement delivery array corresponds to the problem of coloring the edges of a bipartite graph by the principle of Strong edge-coloring.
This thesis investigates the minimum number of colors required to color some popular classes of graphs like paths, cycles, and star graphs and their derivatives. This is followed by an analysis of the factors influencing the strong chromatic index of graphs derived from them. A detailed analysis of the strong edge-coloring of graphs derived from cycles and families of graphs related to cycles is included.
In addition, graphs are classified based on the stability of χ′s(G) under graph operations like vertex deletion, edge deletion and subdivision of edges. Further, there is a discussion on how the parameter varies when new graphs are constructed by duplicating graph elements, generating the line graph L(G) of the given graph G, inflating a given graph G and generating graph products from two graphs, G1 and G2.
The algorithmic aspects of the strong edge-coloring problem are also discussed by defining an algorithm that examines if an assignment of colors for the edges of a graph G can represent a placement delivery array pertaining to a wireless network by verifying if the assignment corresponds to the definition of strong edge-coloring. Two algorithms that color the edges of path graphs and cycle graphs in linear time are also discussed
Enhancing the Efficacy of Task-Based Grammar Teaching: A Study through Error Analysis of ESL Learners at the Tertiary Level
No full textThis study aims to determine the effectiveness of modern methods of teaching grammar and to test the student\u27s learning through activities and games. The objective is to identify the students\u27 grammatical errors regarding prepositions, articles, concord, tenses, and redundancy by practical methods and task-based activities. The study employed Corder’s Error Analysis method to understand the students\u27 language learning process, indicate errors, and identify opportunities to develop learners\u27 language awareness.
A pilot study was conducted involving both pre test and posttest for the students. The primary research involved pre test, posttest and retention tests for the students to evaluate the error analysis better. The study has also employed modern methods like the Cooperative Learning Method (CLM) and Blended Learning with Flipped Classroom (BL&FC). The tasks associated with CLM include Jigsaw Strategy and Think-Pair-Share, and the tasks related to BL & FC include Froggy Play and Teacher Student Flipped Role-Play.
The study plays a vital role in designing engaging lesson plans to accomplish real-life objectives, shifting a teacher’s role to facilitator and mentor, curating the students\u27 English language interests through meaningful tasks with grammar in context and encouraging active learning production. The present study is beneficial to the students
for rectifying the errors, helping the teachers to incorporate innovative teaching strategies, identifying applying suitable methods and restructuring the syllabus
Hybrid Hydrolysis and Fermentation of Prosopis Juliflora Pods for Biohydrogen Production by Dark Fermentation
Get PDFThe rapid consumption of fossil fuels has resulted in the energy crisis and many environmental issues, including air pollution and the greenhouse effect. Hydrogen is the independent source of the highest energy content, with 122 KJ g-1. Biohydrogen produced from lignocellulosic biomass (LCB) is an excellent alternative fuel for its cleanability, renewability and sustainability. Biohydrogen production from dark fermentation using lignocellulosic biomass provides low cost and a sustainable pathway to utilize a vast amount of waste.
Dark fermentation has considerable potential for hydrogen production because it does not require sunlight, allowing for full-time operation and minimizing bioreactor complexity. The major bottleneck of lignocellulosic-based biohydrogen production is separating and breaking the major polymers into fermentable sugars. Inoculum plays an essential factor in biohydrogen production under dark fermentation. Anaerobic sludge containing mixed microbial cultures could offer a complete pathway during biomass to biofuel conversion.
Mixed consortia could metabolize and tolerate metabolic compounds that act as metabolic inhibitors, such as acetic acid and hydroxy methyl furfural. Process integration using enzyme cocktails in the LCB biorefinery requires fewer enzymes, improving product formation and reducing cost. HHF involves integrating simultaneous hydrolysis and fermentation of biomass without compromising the hydrolysate yield.
Thus, the present study evaluated the hybrid enzymatic hydrolysis and fermentation of Prosopis juliflora pods (Pj pods) for the enhanced Biohydrogen production from the activated anaerobic sludge through the waste-to-energy approach (WtE). The onsite-produced cellulolytic enzyme cocktail from the newly isolated Trichoderma harzianum BPGF1 hydrolyzed the sulfuric acid-treated Pj pods. After the separate enzymatic hydrolysis, the acid- treated Pj pods produced 342.51 mg/gds glucose. The sesame oil-treated anaerobic sludge has more hydrogen-producing Clostridium species and less hydrogen-consuming bacteria.
After the optimization, a maximum biohydrogen yield of 7366±164.12 μmole H2/gds and 108.690±2.82 mmole H2/L was achieved under anaerobic conditions. Thus, the HHF was proven to be a more efficient and reliable approach for biomass\u27s enzymatic hydrolysis and fermentation to produce biofuels & biochemicals. Using onsite-produced enzymes for the Hybrid hydrolysis and fermentation for biohydrogen production is new and novel in the present report. Also, the present study, for the first time, explored sesame oil as a source of LCFAs for suppressing hydrogen consumers in the inoculum
Preparation And Efficacy Evaluation Of Chicken Egg Yolk Sourced Igy Against The Venoms Of Cobra, Krait, Russell’s Viper, And Saw-Scaled Viper
No full textEnvenomation resulting from snakebites is widely recognized as an alarming health risk in tropical and sub-tropical areas. The big four snakes including Naja naja, Bungarus caeruleus, Daboia russelli, Echis carinatus are responsible for most of the envenomation in India. The current therapy for snake envenomation is immunoglobulins, produced from serum or plasma of horses or sheep. To overcome the drawbacks of current antivenom, chicken egg yolk (IgY) antibodies have recently emerged as one of the most promising research avenues.
In this study, the efficacy of chicken egg yolk sourced antisnake venom (ASV) IgY against the big four venoms was evaluated by in-vivo and in-vitro experiments. Lethal dose determination studies in mice and chickens reveal that krait venom is more potent. The sub-lethal doses of venoms were immunized to the chickens and the titre was 1:64000 against all the venoms. On testing the scalability of IgY, water dilution method followed by tangential flow filtration and further purified by Ion-exchange chromatography would be suitable for large scale production of IgY.
IgY was found efficient in neutralizing the hemotoxic and pro-coagulant activities of venoms. Interestingly, IgY was able to inhibit the myotoxicity and nitric oxide production (inflammatory marker) in a dose-dependent manner. Further, study on the neutralization potency of IgY in mice had shown antivenom IgY raised against Bungarus caeruleus (0.028mg of venom/mL of ASV IgY) and Naja naja (0.22mg of venom/mL of ASV IgY) was very much congruent with the commercial antivenom IgG (Bungarus caeruleus - 0.035 mg/mL of ASV IgG; Naja naja - 0.28mg/mL of ASV IgG), while potency of IgY against Echis carinatus
(0.442mg of venom/mL of ASV IgY) was better than the commercial antivenom IgG (Echis carinatus - 0.095 mg of venom/mL of ASV IgG). Anti-Echis carinatus IgY was highly effective in neutralizing 2xLD50 dose of venom. However, the neutralization potency of IgY was less against Daboia russelii venom compared to other venoms. IgY exhibits pronounced inhibition against the edema-forming and haemorrhage activities induced by the venoms demonstrated in mice models
Aerodynamic Investigation of NACA 0020 Airfoil with Extended and Serrated Trailing Edge at Various Turbulent Intensities
No full textLift (upward force) is a significant aerodynamic component that directly relates to the aerodynamic efficiency (lift-to-drag ratio) of the airfoil. Enhancement of airfoil lift is important for industries like wind turbines, aircraft, and turbo machinery. The present study investigates the NACA series airfoil by modifying the trailing edge in the form of extension and serration. The angle of attack was changed from 0° to 35° instep of 5°, and the airflow Reynolds number was fixed as 2.14 × 105. To figure out the flow behavior, surface pressure has been collected from the 50 pressure ports provided over the airfoil surface. The extended trailing edge of amplitude (10%c, 20%c, and 30%c) is designed and fitted with the conventional airfoil.
Further, the triangular serration is introduced with the wavelengths of 20%c, 40%c, and 60%c and equipped with the conventional airfoil at the trailing edge and tested in the wind tunnel. The change in surface pressure coefficient and aerodynamic force coefficient are presented. As a result, excellent lift increment is favoured by the extended trailing edge, a thin, long surface attached to a conventional airfoil. By modifying the flow pattern, the serrated trailing edge functions as a flow control mechanism, delaying the stall phenomenon.
Airfoils employed in aircraft wings or turbine blades exposes to open atmosphere, where the turbulence intensity (measure of air stability) often changes. Turbulence intensity is measured by calculating the ratio of fluctuated velocity (u’) to the mean velocity (u∞) for a particular sampling frequency, in the current work the sampling frequency was fixed as 850 Hz.
The conventional airfoil, with and without extended and serrated trailing edges, of all designed cases is tested under the turbulence intensity (T. I) of 0.3%, 3%, 5%, 7% and 12%. On reaching T. I values of 7% and beyond, the lift performance falls, as at higher freestream turbulence, the complication takes place between the interaction of freestream turbulence and flow adjacent to the airfoil surface. This makes the aerodynamic performance to fall at very higher turbulence intensity.
However, the lift value falls very smoothly (i.e. soft stall), as alpha is increased. This is the similar trend of trailing edge stall, the separation point moves downstream nearer to the trailing edge at higher freestream turbulence intensity. However due to increase in friction drag, the aerodynamic efficiency falls with conserved stall characteristics. The airfoil with extended trailing edge and serrated trailing edge performs well compared to the conventional airfoil, even at higher levels of turbulence intensity
Study on the Rights of Parties in Live-In Relationships in India - A Case Review Approach
Get PDFHeterosexual live-in relationship is viewed as a stigma in Indian society. However, through a plethora of judgments, the Apex Court of India granted monetary relief and physical protections to couples in live-in relationships. While so a few High Courts had refused to grant protection to the live-in couples by stating that giving such rights and protection would destroy the country\u27s social fabric.
View of such High Courts reflects on the opinion that our Courts indeed have different ideas while granting reliefs to persons in live-in relationships. Catena of judicial decisions explained this relationship as a walk in and walked out relationship. Nevertheless, the Supreme Court has ruled that couples in a live-in relationship can take shelter under the bundle of rights granted under Article 21 of the Constitution of India. Societal morals can be subjective, but laws and the right to life cannot be so. Hence, the researcher attempted to study the legal status of parties in the Live-in relationships.
In India, there is no specific legislation regulating the issues around live-in relationships. From the period of ‘Sati’ to the contemporary times of honour killing (murder based on caste), the relationships between a man and a woman, or a man and man, or woman and woman, or the recognition of other queer relationships, have always been built around societal acceptance. However, it creates a new spectrum of constitutional challenges on the personal laws regarding this issue of live-in relationships
Investigation of Fault Detection and Redundant Control Strategy for Model Predictive Control of Distillation Column
Get PDFModel Predictive Controller (MPC) is one of the industrial-ready control systems and an ideal choice for complex, slow-varying, and energy-intense Distillation Columns (DC). However, MPCs are subjected to failures and their performance degrades with faults and disturbances. Hence, there is a need for a redundant control strategy to ensure the continuous operation of MPC-controlled DC, which is investigated in this work.
A pilot-plant binary DC used to separate methanol and water is implemented with a computer-controlled system and is subjected to Pseudorandom Binary Excitation Signals (PRBS). The output response acquired is used to develop a MIMO (Multi-Input Multi- Output) state-space model of DC, which exhibits an 85% fit percentage. MPC is designed using a state-space model and various Quadratic Problem (QP) solvers used for cost function minimization are analyzed. Among the three QP solvers considered, the Iterative Interior Point (IIP) solver provides optimal control action amidst noises and disturbances.
DC is a multi-variable process with a significant number of sensors and actuators making fault inevitable. Canonical Cross-Correlation (CCA)-based fault detection is developed to detect faults in actuators (stiction and dead band), sensors (drift and bias), and controllers of DC. Genetic Algorithm (GA) is used to tune the threshold that minimizes false detection and provides about 96.54% of fault detection accuracy on average.
A redundant control strategy is vital to ensure a reliable MPC under various abnormal operating conditions like unbounded disturbance and controller failure. Autotuned PID controller has been considered to provide redundancy for MPC failure. An on-demand GAbased controller tuning technique inspired by MPC is developed to tune PID parameters. A Graphical User Interface (GUI) is also developed to monitor and control the DC.
Finally, an experimental investigation of the proposed redundant control system is carried out and compared with conventional MPC. About 87.7% reduction in Integral Time Absolute Error (ITAE) performance metric is observed during MPC failure, which demonstrates the reliability and capability to ensure continuous operation of the DC
Molecular Insights Of Paraoxonase 2 In Advanced Glycation End Product Induced Endothelial Dysfunction
Get PDFDiabetes mellitus (DM) is a metabolic disorder associated with various vascular complications and affects the function of the endothelial cells. Elevated blood glucose levels accelerate the formation of advanced glycation end products (AGEs) by Amadori rearrangement and bind to their Receptor for the advanced glycation end product (RAGE) and evoke release of key pro-inflammatory cytokine proteins leading to endothelial dysfunction. Paraoxonase 2 (PON2) is an endogenous intracellular enzyme, localised in mitochondria, endoplasmic reticulum (ER), and nuclear membrane with numerous properties, like anti-inflammatory, anti-apoptotic and anti-oxidant.
Our present study aims to ascertain the effect of AGEs on PON2 activity and expression, and its consequences on endothelial dysfunction (ED) in both macrovascular and microvascular endothelial cells. In Human umbilical vein endothelial cells (HUVECs), AGEs (Glycated Albumin (GA) or CML) exposure significantly increased the expression of various receptors, which ultimately decreased the activity and expression of PON2 with elevated level of Reactive oxygen species (ROS), ER stress proteins and pro-inflammatory cytokines levels. Overexpression of PON2 significantly reduced ROS and ER stress through reduced Nuclear factor kappa B (NFκB), and extracellular signal-regulated protein kinase (ERK1/2) phosphorylation.
Mitochondrial dysfunction is one of the key pathological changes seen in diabetes patients and also induces dysfunctional endothelial cells thereby contributing to the pathology of DR. We found that PON2 protein was reduced in human retinal microvascular endothelial cells (HRECs) upon CML treatment and also in the diabetic retina (p=0.035). Silencing of PON2 augments Fission-1 (Fis1), resulting in fragmentation of mitochondria, and facilitates mitochondrial permeability transition pore (mPTP) opening, which induces the release of cytochrome-C (Cyt-c), and activates pro-apoptotic pathway.
While PON2 overexpression was similar to SP600125 (a specific JNK (c-Jun Nterminal kinases) inhibitor) in decreasing Fis1 (p=0.036) and reduces the phosphorylation of JNK1/2 signaling pathway confirming the anti-apoptotic role of PON2 in CML-mediated mitochondrial dysfunction. Since, PON2 a multifaceted enzyme, decreased in diabetes and glycation decreases its activity in diabetes, therefore we aimed at constructing a mutated PON2 that can defy glycation.
To deduce the glycation-prone residues in PON2, we used an in silico approach and developed a mutated mPON2 by SDM assay, and compared the efficiency of both wPON2 (wildtype PON2) and mPON2 (mutant PON2-PON2-K70A) in HRECs upon CML treatment. We deciphered CML glycates wPON2 and reduces its activity and mPON2 designed using in silico studies found to interact much better with its substrates than wPON2. Further overexpression of mPON2 show enhanced inhibition of CML-induced oxidative, ER stress, pro-inflammation, and mitochondrial fission than wPON2.
Additionally, mPON2 inhibited the CML-induced phosphorylation of NFĸB, similar to Pyrrolidine Dithiocarbamate (PTDC-an inhibitor of NFĸB) treatment. Hence we report inferring the functional implications of mPON2 in mitigating ER stress and inflammation against CML induced vascular dysfunction. Our Overall, analysis of all these results showed a PON2 as a highly promising potential therapeutic target against diabetic micro and macro vascular disease reducing the AGEs induced ROS, ER stress, inflammation and mitochondrial dysfunction
Investigation of Machine Learning Driven Adaptive Control Strategy for Heat Exchanger under Varying Fouling Conditions
Get PDFFouling is an undesirable and inevitable phenomenon that affects Heat Exchanger (HE) dynamics, increases maintenance cost (\u3e50%), and loss of production. Conventional fouling prediction and control techniques demand an in-depth understanding of the HE-specific fouling dynamics. Hence, machine learning emerges as an ideal tool for learning the fouling process from the available measurement dataset.
The proposed work aims to design a machine learning-driven adaptive control technique for an industrial HE, subjected to varying fouling conditions. Naphtha cooler, an industrial HE utilized in petroleum refineries, employs cooling water to lower Naphtha temperature, but the high impurities in the recycled cooling water leads to fouling. In this work, a Linear Parameter-Varying (LPV) model with Fouling Resistance (FR) as the drive parameter is developed using the data acquired from the Naphtha cooler at different fouling conditions. LPV model shows a model fit percentage of 89.30%, which is higher than other standard models.
Random Forest (RF) integrated Long-term Short-term Model (LSTM) is developed to predict FR. Experimental investigation shows good performance with the coefficient of determination ( ) of 0.9770. Robust analysis indicates the proposed RF-LSTM to predict FR accurately even with noisy measurements. Dual Extended Kalman Filter (DEKF) is modified to include RF-LSTM as a guiding input for FR estimation. Multiobjective Genetic Algorithm (GA) is used to tune the weights for the modified FR prediction. Five different fouling conditions are used to evaluate the FR estimation performance and show an improvement of FR estimation by 38.49% on average.
A novel Iterative Quality Weighted Interpolation (IQWI) is proposed to derive the model parameters from the LPV. It is based on model quality to determine the optimal model parameters and a 24.44% improvement in model parameter estimation is observed. Model parameters from LPV are used to define an accurate prediction model and are used by adaptive MPC to effectively control the HE. Comparative analysis illustrates the reliable performance of the adaptive MPC under FR variations. Adaptive tuning of MPC parameters like horizons, weights, and constraints based on the HE fouling condition will be investigated in the future
Phosphorene as a Chemical Nanosensor for Volatile Organic Compound Vapours - A DFT Outlook
Get PDFBased on the density functional theory framework, the structural stability of phosphorene allotropes and its various nanostructures are ensured. The various allotropes of phosphorene and its nanostructures such as nanosheets, nanoribbon and nanotubes are used as adsorbing materials for various volatile organic compounds (VOCs) such as alcohols, chloroform, amines and aldehydes. The results of adsorption energy are used to confirm physisorption or chemisorption of VOCs on phosphorene. In addition, the charge transfer outcome suggests whether phosphorene is acting as acceptor or donor of electrons upon interaction of target VOCs.
The electronic attributes such as band structure, projected density of states (PDOS), electron density difference (EDD) is used to study the variation of electronic properties of phosphorene upon adsorption of VOCs. Besides, the response of phosphorene is ensured based on the results of relative energy gap variation owing to VOCs adsorption. Moreover, we considered different phosphorene nanostructure and various vapours.
However, the adsorption of trimethyl amine (TMA) and dimethyl amine (DMA) on black phosphorene nanotubes, adsorption of chloroform vapour on blue phosphorene nanoribbon, methanol and ethanol vapours adsorption on stair phosphorene nanosheets and formaldehyde and acetaldehyde vapour adsorption on zipper phosphorene sheets are observed to be optimum. The present report opens the avenue on using various phosphorene allotropes to detect different VOCs