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Valorization of Agricultural Byproducts into Sustainable and Active Food Packaging Systems
No full textGlobally, plastic production is mounting to new heights every year, along with its waste accumulation in the environment. Predominantly, food packaging consumes colossal amounts of synthetic plastics over any other packaging materials due to their undeniable advantages. However, the non-biodegradable nature, insufficient recycling rates, and migration of additives necessitate a sustainable alternative. Biopolymers (i.e., biodegradable polymers) stand out as a viable alternative; they are from renewable sources and are biodegradable in the end. In that regard, biodegradable packaging materials developed using agricultural byproducts could be a novel strategy to overcome the environmental and economic concerns in the processing industries. This thesis demonstrates a feasible route to divert underutilized agricultural byproducts into sustainable materials for food packaging applications. This thesis investigates the potential of three different starches from byproducts (jackfruit seeds, jamun seeds, and litchi seeds) and xyloglucan from tamarind kernels in film forming to obtain strong mechanical, water-resistant, and antimicrobial/antioxidant properties. To achieve this goal, three strategies have been explored, namely starch recovery, starch-xyloglucan complexing, and active nanoparticle incorporation. In the first part of this thesis, jackfruit seed starch (JSS) and tamarind kernel xyloglucan (XG) were extracted from their sources. The JSS films displayed weaker mechanical and water vapor barrier properties than XG films. The blending of XG with JSS improves the material strength attributed to intermolecular interactions. Furthermore, JSS/XG nanocomposite films were synthesized by incorporating zinc oxide nanoparticles (ZNPs). The ZNPs-incorporated films demonstrated increased surface hydrophobicity and water resistance. Loaded ZNPs effectively transferred stress to the interface and enhanced the tensile strength (20.65 MPa), elongation at break (38%), and elastic modulus (0.39 GPa). The nanocomposite films showed strong growth inhibition activity against Staphylococcus aureus and Escherichia coli. Additionally, the JSS/XG/ZNPs coated tomato fruits resulted in delayed weight loss (up to 40%) compared to uncoated fruits at the end of storage. In the second part, bio-nanocomposite films using jamun seed starch (JaSS), tamarind kernel xyloglucan (XG), and chitosan nanoparticles (ChNPs) were developed. The blending of JaSS and XG promotes a dense polymer network with enhanced packaging attributes in the composite films. The addition of 3% w/w ChNPs significantly enhanced the tensile strength (20.42 MPa), elastic modulus (0.8 GPa), and surface hydrophobicity (89°), along with reduced water vapor permeability (4.32 × 10-9 g m-1s-1Pa-1) of the JaSS/XG films. The films exhibited strong antimicrobial activity against Bacillus cereus and Escherichia coli. More interestingly, a JaSS/XG/ChNPs coating applied on sapota fruits retarded the weight loss and color change up to 12 days of storage. In the third part, starch from litchi seeds (LSS) was extracted, and composite films were developed with xyloglucan (XG) and lignin nanoparticles (LNPs). The XG addition strengthened the weak polymer networks of LSS and improved the rheological, molecular, morphological, mechanical, and barrier properties. The lignin nanoparticles loading into the LSS-XG network further increased the tensile strength (14.83 MPa), elastic modulus (0.41 GPa), and surface hydrophobicity (80.07°) and reduced the water vapor permeability (5.63 × 10-7 g m-1s-1Pa-1). The phenolic hydroxyls of LNPs imparted strong UV-shielding and free radical scavenging activities to the composite films. These attributes aided in preserving the quality of coated banana fruits with minimal weight loss and color change. The last part presents the discussion of the resultant properties among the prepared bio-nanocomposites. LSS films exhibited the highest strength, stiffness, and water vapor permeability. JaSS films showed the highest flexibility and least water solubility. JSS films demonstrated the highest surface hydrophobicity and water vapor barrier. The complexing of starch and xyloglucan synergistically enhanced the intrinsic properties of starch films. The inorganic ZNPs enhanced maximum strength, stiffness, and antimicrobial activity, whereas the organic ChNPs and LNPs effectively enhanced the water-resistant attributes of the composite films. Overall, this research highlights the potential transformation of underutilized abundant byproducts into sustainable active bio-nanocomposites for food packaging applications. The prepared active bio-nanocomposites exhibited a promising potential in retarding the quality deterioration of highly perishable fruits that extends the shelf life and mitigates the economic and nutritional losses
Analysis and Implementation of AI Approaches Towards Terrain Exploration and Control of Humanoid Locomotion
No full textExploring an optimal path for Humanoid locomotion is a challenging task that demands a smooth and collision-free path. The current research discusses various path-planning algorithms to achieve the objectives. The classical-based Linear regression model, memory- less Gravitational Search Algorithm (GSA) models, and memory-based Harris-Hawk optimization (HHO), Archerfish Hunting Optimization (AHO), and Slime Mould (SM) models are introduced for effective path planning of the NAO robots. The modifications to the standard approaches, hybridization of the different standalone models, and tuning of the different standalone models using the classical approach are performed to evaluate the effectiveness of the different models. Path exploration is performed simultaneously in both environments with static-only and static and dynamic obstacles. The Petri-net model is used for path planning to overcome collisions with dynamic obstacles in a dynamically complex environment. Also, the camera-vision approach is introduced to perform path exploration in an environment with uneven floor conditions. To further evaluate the performance, the different models are compared with the existing approaches developed using different approaches in other complex environments. Improvements of more than 5% were recorded using the different controllers. The different modified and hybrid models showed optimal performance compared to the existing research. Further, the improved models showed an efficient path exploration compared to the standard models in various complex terrains
Construction of Integrated (bio) Degradation and Adsorption-based Approach for Treatment of Diversified Pharmaceutical Compounds
No full textA wide range of pharmaceutically active compounds (PhACs) have been recently detected in different types of ground and surface waters all over the world. Among these compounds, non-steroidal anti-inflammatory drugs (NSAID) and antibiotics were found most abundantly due to their unrestricted and unmonitored use and disposal. The conventional water treatment techniques were found inefficient in managing these contaminants, raising the need for specialized techniques to treat such micropollutants. The current study initially addressed diverse PhACs including NSAIDs, antibiotics, and dyes. Six different bacterial strains were isolated from the pharmaceutical wastewater, specialized to degrade particular PhACs which include five different pharmaceutical azo dyes (indigo carmine (IC), tartrazine (TAR), quinolone yellow (QY), sunset yellow (SY), and amaranth (AM)) and two NSAIDs (paracetamol and diclofenac (DCF)). The underlying process of biodegradations for each PhAC was studied and optimized to obtain the best degradation efficiencies. The degradation efficiency of the azo dyes was 99.91%, 99.87%, 96.89%, 93.98%, and 99.71% for IC, SY, TAR, QY, and AM, respectively. After optimization, the degradation efficiency for paracetamol was 92.35% (Ci = 3 g/L), whereas for DCF, the same was 99.82% (initial concentration, Ci = 500 mg/L). Moreover, the presence of antibiotics could interrupt the biodegradation of PhACs and spread antibiotic resistance. Hence, this current study resolved this issue by implementing an adsorption strategy for the removal of antibiotics from the wastewater. Two different bio- adsorbents, 700 °C rice straw biochar, and 200 °C torrefied coco peat developed for the removal of two different antibiotics doxycycline (Dox) and norfloxacin (NFX), respectively, representative of the two most used antibiotic family, tetracycline and fluoroquinolone, respectively. The removal efficiency of the mentioned antibiotics was found to be 99.82% (Ci =500 mg/L) and 99.52% (Ci = 500 mg/L), respectively. The adsorption mechanism, kinetics, and isotherm studies were also performed. The desorption study revealed that for both bio- adsorbents, 90% ethanol was found to regenerate the adsorbent. Further, all of the individual processes were integrated to demonstrate the successful PhAC removal from synthetic wastewater formulated by mixing azo-dyes, paracetamol, DCF, Dox, and NFX. The primary step of the designed integrated process was the single-step adsorption of the antibiotics using biochar. The antibiotic removal from the wastewater was monitored by a minimum inhibitory concentration test using the Escherichia coli DH5α strain. Untreated wastewater exhibited almost 100% growth inhibition at 1% concentration. However, significant growth of E. coli was observed up to 4% concentration of treated wastewater. Moreover, the FITR spectra of the adsorbents confirmed the antibiotic removal. Biodegradation of the residual PhACs was performed in an aerated reactor which was confirmed by monitoring different water quality parameters. The COD and TOC of the synthetic wastewater were reduced by 92.32% and 87.47%, respectively. The ecotoxicological study using Aliivibrio fischeri (ATCC 7744) confirmed notable depletion in the ecotoxic load (97.71%) of the wastewater signifying the success of the integrated process. The techno-economic analysis estimated an expense of $0.03/L of wastewater for a plant with a capacity of 100 kL for each batch. Hence, this current work has successfully demonstrated the implementation of an integrated wastewater treatment policy using bioadsorption and biodegradation technologies for the cost-effective removal of PhACs from wastewater with appreciable efficiencies. The constructed design can be further improved for industrial applications by improving water flow, bioreactor, and plant design. Enhancing detection methods would open opportunities for exploring more compounds and applying the integrated design to address broader wastewater remediation challenges
Application of Electrochemical Impedance Spectroscopy (EIS) to Study the Effect of Different Deposition Parameters During Electroplating
No full textCopper (Cu) electrochemical deposition (ECD) on graphite was studied using Cu (noble metal) and Ni (active metal) to investigate nucleation and growth processes. Cu deposition was analyzed under varying potentials, ion concentrations, and temperatures in acidic and alkaline baths. In acidic conditions, different anodes (Pt and Cu) were used. The electrodeposition was investigated by various techniques i.e., cyclic voltammetry (CV), chronoamperometry (CA), electrochemical impedance spectroscopy (EIS), X-ray diffraction (XRD), atomic force microscopy (AFM) and scanning electron microscope (SEM). From cyclic voltammetry the redox potentials have been chosen. The selected potentials (-0.16 V, -0.26 V, -0.36 V, -0.46 V, -0.56 V and -0.66 V) are the input parameters for i-t curve and EIS. The Nyquist plots revealed that copper ion charge transfer happens at high frequencies and is represented by a single capacitive constant, while at low frequencies copper ion diffusion from the solution to the electrode surface is represented by a Warburg-type contribution. The corresponding Bode plots represent a decent ability between the experimental and fitting data. The effect of potential on double-layer capacitance, diffusion coefficient, and diffusion layer thickness along the interface of electrode and electrolyte has been discussed extensively. The morphologies of the copper particles depositing on the surface of electrode also studied and it shows that copper deposits during electrodeposition resulted in a transition from spherical to dendritic structure as a function of deposition potential. The current density-time (i-t) curve was recorded by the potentiostatic method for 300 sec various potentials, concentrations and temperatures. At low Potentials (-0.16, -0.26 and -0.36 V) Nyquist plots reveal that copper ion charge transfer occurs at high frequency, while at low frequency copper ion mass transfer occurs. At high Potentials (-0.46, -0.56 and -0.66 V) Nyquist plots reveal that copper ion charge transfer occurs at low and high frequency. A fitted equivalent circuit was utilised to determine EIS parameters. The Nyquist plots revealed that copper ion charge transfer happens at high frequencies and is represented by a single capacitive constant, while at low frequencies copper ion diffusion from the solution to the electrode surface is represented by a Warburg-type contribution. The corresponding Bode plots represent a decent ability between the experimental and fitting data. The effect of potential on double-layer capacitance, diffusion coefficient, and diffusion layer thickness along the interface of electrode and electrolyte has been discussed extensively. The morphologies of the copper particles depositing on the surface of electrode also studied and it shows that copper deposits during electrodeposition resulted in a transition from spherical to dendritic structure as a function of deposition potential. The effect of pH on copper electroplating from a cyanide-free alkali medium was studied using copper sulphate, glycine, and sodium hydroxide. Electrochemical impedance spectroscopy (EIS) was used to analyze phase transformations under varying ion concentrations (0.01, 0.05, and 0.1 M), temperatures (5–20 °C), and deposition potentials (-0.56 V, -0.66 V, -0.76 V) determined from cyclic voltammetry (CV). The initial CV and potentiostatic studies reveal that the system is mixed kinetics control one. EIS study further supplement to the observations and it was observed that at low ion concentration (0.01 M) mass transfer was dominated. To complement the EIS results, a thorough phase and morphological examination of the copper films was done by means of X-ray diffraction (XRD), FESEM and AFM. It was revealed that at low ion concentration and potential, the film was not uniform. The films were uniform and consisted of a thin oxide layer with increase of potential and concentration and decrease of temperature. Based on the findings of double layer capacitance and charge transfer resistance along with film resistance, a plausible deposition mechanism has been proposed. However, there can be further critical use of EIS to gain deeper insights into the electrochemical phenomena occurring at the electrode-electrolyte interface to manipulate the film properties as per the desired applications. Again, electrochemical impedance spectroscopy (EIS), chronoamperometry, and cyclic voltammetry are used to investigate Ni electroplating from three different types of electrolytic baths- sulphate, chloride, and watts at silent and ultrasonic conditions. The nucleation and growth mechanism were examined using the EIS method, and it was found that ultrasound had a discernible impact. After applying an applied potential of -1.4 V to deposit nickel, two unique depressed semicircles were observed in the impedance spectrum. These semicircles' frequency and capacitance varied according to the different electrolyte compositions, providing insight into the deposit morphology. According to X-ray diffraction studies, crystallite size decreased in sulphate to chloride bath. Atomic force microscopy and scanning electron microscopy were used to analyse the surface morphology of films produced in the presence of ultrasound and silent condition
Modulation of Electrical Properties of RF Sputtered Tantalum Oxide Based Thin Films for High-k dielectric Applications
No full textIn the past decade, significant research efforts have focused on integrating high-k dielectric materials to replace traditional low-k dielectrics like SiO2. Among these materials, tantalum oxide (Ta2O5) has garnered substantial attention and appears particularly promising due to its high dielectric constant (≈25-30), relatively large energy bandgap (~4.5 eV), better amorphous to crystallization temperatures, and good thermal stability in contact with both silicon and metal gates. These exceptional material properties have made Ta2O5 highly attractive for use as a gate dielectric in Metal-Oxide-Semiconductor Field- Effect Transistors (MOSFETs). Furthermore, resistive switching in metal-oxide-metal structures fabricated using Ta2O5 thin films have demonstrated excellent memory effects, making it a suitable candidate for advanced memristor device applications. Integrating these devices into a monolithic structure, such as a one transistor one resistor (1T-1R) configuration, could potentially achieve high-speed operation, high storage density, and low power consumption. This advancement is facilitated by the use of multifunctional high-k dielectric materials like Ta2O5. Thin films of Ta2O5 have been produced using the radio frequency (RF) magnetron sputtering method. The study investigates the influence of sputtering parameters such as RF power, sputtering pressure, Ar/O2 gas flow ratio, and substrate temperature on the structural, morphological, and electrical properties of the films. The optimizing conditions are found to be RF power of 150 W, sputtering pressure of 1.0 × 10-2 mbar, Ar/O2 gas flow ratio of 3:2 and substrate temperature of 300 °C. Additionally, the impact of conventional annealing and rapid thermal annealing (RTA) at different process conditions, (temperature and duration) on the properties of Ta2O5 films is examined. 800 °C for conventional annealing and 750 °C for 10 min duration for RTA Process were found to be the optimal post-deposition treatment. At these optimal conditions, high dielectric constant, low leakage current, low oxide charge density, and low interface state density are observed. Doped versions of Ta2O5 films, incorporating Zr, and Hf, are synthesized on silicon substrates using RF co-sputtering. The dopant concentration is adjusted by varying the RF power applied to the dopant target while maintaining the RF power of the Ta target at an optimized level. To further modulate the electrical properties of the Ta2O5 thin film, a ZrO2 and HfO2 stacking layer was incorporated with different thickness configurations. An initial investigation was conducted to examine the resistive switching (RS) behavior of Ta2O5 films using a metal/insulating/metal (MIM) structure for memory device applications. This research work aims to investigate the enhanced RS characteristics of Ta2O5 films with varying different process parameter. Specifically, the study explores the effects of dopants and stack layer on the switching behavior of the as-deposited and modified Ta2O5 films. To investigate the structural, morphological, elemental and electrical properties of RF sputtered Ta2O5 thin film with various growth process parameters different characterization techniques were used. A Rigaku Ultima IV multipurpose X-ray diffractometer was used to study the structural properties of all the Ta2O5 based thin film. Nova Nano SEM/EFI field emission scanning electron microscope (EFSEM) was used to performed the morphological study on all sputtered Ta2O5 based samples, while X-ray photoelectron spectroscopy (XPS) from Omicron technology was used to study the compositional analyses of the sputtered films. Park XE7 atomic force microscope (AFM) was used to determine the roughness of the films. Al/Ta2O5/Si MOS capacitors were fabricated to study the electrical properties of the RF sputtered Ta2O5 films. Capacitance- voltage (C-V) and current-voltage (I-V) measurements were performed on the MOS structures using an Agilent E4980A precision LCR meter and a Keithley 6487 Picoammeter, respectively. Further, current-voltage measurements were performed on the metal-insulator-metal (MIM) structures using a Keithley 2410 sourcemeter to study the resistive switching behavior of the sputtered films
Effect of Different Mixing Methods on Fe-MWCNTs MMC Fabricated by Conventional Powder Metallurgy
No full textMulti walled carbon nanotubes (MWCNTs) are considered as a promising reinforcement due to their unique physical and mechanical properties. The properties like light weighthigh strength, superior thermal and electrical properties of MWCNTs has high potential for reinforcement in the conventional materials. Researchers are interested in multi-walled carbon nanotubes (MWCNTs) reinforced metal matrix composites (MMCs) since they can be utilised as functional materials with fascinating thermal and electrical properties as well as structural applications due to their high specific strength. The aim of the current work is fabrication of multi-walled carbon nanotubes reinforced ironbased MMCs by conventional powder metallurgy (PM) route. High to low volume content MWCNTs reinforced five different compositions such as Fe-21, Fe- 4, Fe- 2, Fe-1 and Fe- 0.5 vol. % MWCNTs were chosen for fabrication of the composites. The composites were fabricated by various processes, parameters and atmospheres to investigate the effect on composite powder, microstructure and properties of the sintered composite. MWCNTs were dispersed in iron matrix by planetary milling for long time and short time, turbula mixing, sonicating and mixing in pestle-mortar. For long milling time (12 and 10 h) composite, in every 2 hours of milling, small amount of powder was picked up for characterization. The final synthesis powders and every 2 h milled Powders were characterized by XRD analysis, SEM/FESEM, TEM, particle size analysis and Raman spectroscopy. After successful synthesis, composite powders were cold compacted in a uni-axial hydraulic press and then sintered at three different temperatures of 900, 1200 and 1300 °C for 2 hours under argon and hydrogen gas atmosphere in a tubular furnace. After successful fabrication of composite, finally properties like density, hardness and compression strength of sintered composites were measured by Archimedes’ principle, Vickers hardness tester and UTM respectively. The tribological properties, electrical conductivity and corrosion behavior of composite were also studied. For long milled composite, the effect of milling conditions (wet and dry milling) and volume percentage of MWCNTs on phase evolution, size and morphology of composite powder and also on sintered composites have been studied. The wet milling and dry milling were conducted in toluene and argon gas atmosphere respectively. It has been found from FESEM analysis that 21 vol. % MWCNTs of 12 hours wet milled composite provides uniform distribution of MWCNTs in iron matrix. In case of other composition and long-time milling, MWCNTs are destructed into nano scale amorphous powder and embedded into the iron powder. After 10 h milling, the FESEM pictures demonstrate that the final Fe powder has spherical in shape. From phase analysis of the milled powder, it has been observed that ferrite, austenite, cementite and other iron-carbide metastable phases are evolved during milling. These metastable phases were formed due to mechano-chemical reaction between iron powder and carbon of MWCNTs. Crystallite size, lattice parameter, lattice strain and dislocation density were also derived from XRD data using FWHM. Due to high impact force of balls on powder during milling, it is found that increasing the milling time reduces the crystallite size and increase in lattice parameter, lattice strain and dislocation density. Particle size analysis was done for the milled powders and an average particle size of 7 μm was obtained after 10 hours of wet milling for Fe-2 vol. % MWCNTs. For Fe-21 vol. % MWCNTs, it has been noted that the average particle size drops from 100 to 13 μm after 10 hours of milling. Moreover, the wet milled powders are fine (average size d50 = 10 μm) and exhibit narrow size distribution whereas dry milled powders (average size d50 = 90 μm) show wide range binomial distribution. The internal morphology of milled powder was investigated by using transmission electron microscopy (TEM). By using Raman spectroscopy, the structural stability of MWCNTs was investigated. The morphology of sintered samples was observed by optical microscope and SEM/FESEM. It has been observed that clear grain and grain boundaries are formed for the composite sintered at 1300 C. At high temperature, enhanced particle-particle bonding occurred due to high rate of diffusion. The XRD patterns of sintered samples show the presence of high intensity sharp peaks of -Fe with a very less intensity of austenite and very weak peaks of iron oxide. Hence, the metastable iron carbides and austenite phases disappeared and iron oxide (Fe3O4) was formed a long with ferrite after consolidation at all temperatures. For high (21) vol. % Fe-MWCNTs composite, the maximum relative density, hardness and compressive strength values were found in Fe-21 vol. % MWCNTs wet milled, sintered at 1300 C for 2 hours composite and reported to be 92 %, 450 VHN and 525 MPa respectively. For all compositions, it has been found that density, hardness and compressive strength of composites increase with increase in sintering temperature due to improved particle-particle bonding. Among low volume (X=0.5, 1, 2 & 4) content MWCNTs reinforced composite, Fe-1 vol. % MWCNTs reinforced wet milled iron composite sintered at 1300 C for 2 h has achieved the maximum relative density, Vickers hardness and compressive strength having 90 %, 350 VHN, 800 MPa respectively. The optimum properties achieved at Fe-1 vol. % MWCNTs is due to proper dispersion of MWCNTs inside the iron matrix. For short milled and without milled iron-MWCNTs composite, it is found that no appreciable destruction or distortion of MWCNTs are found after 20-minute milling or turbula mixing. Moreover, no solid solutions (ferrite and austenite) or iron carbides phases were evolved during the processing of the composite powder. For short milled and without milled powder, it has been observed that MWCNTs are stable; retain their structure after milling and consolidation. In short milling and without milling; both iron powder and MWCNTs are absorbed less mechanical forces compared to long milling. The maximum density, hardness and compressive strength of 86 % relative density, 170 VHN and 425 MPa respectively were found in Fe-4 vol. % MWCNTs composite when consolidated in argon gas at 1300C for 2 hours. From short milled and without milled iron-MWCNTs composite, some samples were selected for non-lubricated sliding wear, electrical conductivity and corrosion study. It has been found that Fe-0.5 vol. % MWCNTs composite sintered at 1300C in argon exhibits higher wear resistance than other composites. The electrical conductivity of the composites increases with increase in MWCNTs amount up to 2 vol. %, beyond that conductivity decreases. Iron-0.5 vol. % MWCNTs metal matrix composite sintered in H2 at 1300 C shows better corrosion resistance than other composites
Sequence Labeling Tasks for Odia Language
No full textThis comprehensive thesis delves into the intricate landscape of natural language processing (NLP) for low resource languages, primarily focusing on Odia, an Indo Aryan language spoken predominantly in the Indian state of Odisha. This language face unique challenges in the development of NLP applications due to the scarcity of linguistic resources and annotated data. The primary focus revolves around addressing the inherent limitations of low-resource languages, explicitly emphasizing the construction of annotated datasets and the subsequent development of systems for the fundamental task of Odia language, such as sequence labeling. The overarching objective is to contribute to the enhancement of NLP applications for Odia, particularly in the domains of Part-of-Speech (POS) tagging, Named Entity Recognition (NER), and chunking. The first objective of the research involves an in-depth investigation into the construction of annotated datasets tailored for sequence labeling tasks. Given the scarcity of linguistic resources and annotated data in low-resource languages like Odia, the methodology adopted for dataset creation is meticulous and resourceful. This corpus, precisely curated and annotated, spans various domains, text types, and linguistic nuances. Its creation involved extensive data collection efforts, linguistic analysis, and annotation by domain experts, resulting in a valuable resource for Odia language research. This stage serves as the foundational building block for subsequent developments, ensuring the availability of high-quality annotated data for training and evaluation purposes. The second phase of the thesis focuses on the development of systems for sequence labeling tasks, commencing with POS tagging. A baseline model is established using Conditional Random Fields (CRF) for the development of Odia POS tagger. Subsequently, the thesis explores advanced modeling techniques, incorporating Convolutional Neural Networks (CNN), Long Short-Term Memory networks (LSTM), and transformer models to refine and elevate the accuracy of the POS tagger. Each model is meticulously fine-tuned to the unique linguistic characteristics of the Odia language, offering a nuanced understanding of context and semantics. The third phase of the research extends the developed methodologies to the creation of a phrase chunking system. Leveraging the foundation laid by the annotated dataset and the insights gained from the POS tagging system, the chunking model is designed to capture syntactic structures and linguistic nuances specific to Odia. Similar to the POS tagging phase, CRF, CNN, LSTM, and transformer models are employed to iteratively enhance the results and adaptability of the chunking system. The final stage of the research culminates in the development of a Named Entity Recognition (NER) system. Drawing on the knowledge gained from the preceding phases, the NER system is crafted to identify and categorize named entities within Odia text. The utilization of diverse modeling approaches, including CRF, CNN, LSTM, and transformer models, ensures a comprehensive and nuanced understanding of named entities in the context of the Odia language. Throughout the thesis, an exhaustive evaluation process is undertaken to assess the performance of each developed system against established benchmarks and existing NLP tools for Odia. Comparative studies and detailed evaluations provide insights into the effectiveness, superiority, and practical utility of the proposed solutions. The robustness and adaptability of the developed frameworks across different domains and genres underscore their applicability in real-world scenarios. This thesis represents a significant and multifaceted effort aimed at addressing the challenges posed by low-resource languages in the realm of NLP. The construction of annotated datasets and the development of advanced systems for sequence labeling tasks in Odia not only contribute to linguistic research but also hold immense potential for linguistic preservation, digital inclusion, and technological innovation. The outcomes of this research pave the way for a future where all languages, irrespective of their resource constraints, can thrive in the digital age
Development of Novel Meta-heuristic Algorithms to Optimize the Locations, Type and Ratings of the FACTS Devices in Load Flow Studies for Enhancement of the Power System Operations
No full textThe current research study probes into the utilization optimization algorithms which are inspired from natural phenomenon for the optimal allocation of FACTS controllers in IEEE bus systems. The main focus is to enhance the system performance by minimizing the active power loss, voltage deviations, and installation cost of FACTS, and maximizing the system loadability. Such study while pursued to determine the location, type, and rating of FACTS controllers by applying the metaheuristic methodologies yielded contributions in definite domains, involving the development of some new variants of existing algorithms. From the viewpoint of algorithms these encompass Jaya blended Moth Flame Optimization technique, augmented Ant Lion Optimization method, Probability Distribution based Salp Swarm Algorithm, and hybrid Ant lion-Moth Flame-Salp Swarm Algorithm which have been very successfully applied to optimal placement of FACTS devices for the first time both in their original and tweaked forms. Moreover, on the other hand, when metaheuristic techniques are being experimented with, the objective function which is optimized, includes single as well as multiple objectives. While the single objectives are modelled to minimize the active power loss and voltage deviations separately, the multiple objective category aims to minimize the active power loss, voltage deviations, and installation cost of FACTS controllers along with the maximization of system loadability. The outcomes acquired by applying the prospective algorithms using both the single and multiple objective formulations are highly profound and motivating. The aforesaid statement can be further strengthened by highlighting some significant quantitative results. The following table gives an insight into the analysis done where the values corresponding to the winning algorithms have been highlighted in bold. Also, the graphical analysis by comparing the performance of the algorithms based on the installation cost of FACTS devices and the system loadability for the same case study as tabulated above has been depicted in the figure below. These deductions have rightfully justified the proposed contributions evolved in the present investigation and the efficiently developed methodologies have surfaced as promising contenders in competition with their counterparts in the metaheuristic optimization realm
Grid Integrated Smart Charging Management of Electric Vehicles for Demand Response in Distribution System
No full textThe ever-increasing energy demand accompanied by fossil fuel depletion and environmental degradation has paved the way for transportation electrification. Electric Vehicles (EVs) are environmentally friendly alternatives to conventional Internal Combustion Engine (ICE) driven vehicles. For large-scale deployment of EVs, sustainable charging infrastructure needs to be developed. However, the increasing popularity of electric vehicles will pose a significant threat to existing electric grids due to added load of electric vehicles in the power systems distribution network. This thesis provides the solution for stabilizing electric grid health through two objectives. First is to charge EV batteries at variable charge rates, and second, to provide utilities with active and reactive power support using EV batteries and charging stations, respectively. This will essentially level the utility load throughout the day by providing power to charge EV batteries during off-peak hours, and, on the other hand, utilities will take power from EV batteries for peak power shaving during peak power demand hours of the day. The peak shaving and valley filling potential of the energy management system (EMS) is investigated in high-rise residential buildings equipped with PV storage systems. The battery bank is capable of charging from the off-peak load of the grid with PV generation. The EMS could effectively reshape the net electricity demand profile and match customer demand and PV generation. The charging station placement problem is a complex problem involving the power distribution network and road network. The charging stations must be placed in the distribution network in such a way that the negative impact of the placement of charging stations on the operating parameters of the distribution network is minimized. The impact of EV charging stations on operating parameters of the distribution network, such as voltage stability, load variance and power losses, are thoroughly analyzed in this thesis. Differential evolution optimization is developed and used for solving the charging station placement problem. The proposed formulations of the charging station placement problem are validated on superimposed IEEE 33 bus distribution. Currently installed transformers are of a certain fixed rating and cannot accommodate the rapid continuous growth, resulting in the utility not being able to meet the power demand. The concept of load shedding is utilized when supply cannot meet demand due to certain system constraints and demand reduction is required. The demand response is made to support EV fleet connected to the distribution circuit while assuming that the first peak demand can be met. The Programmable logic control (PLC) for EV demand side integration follows two categories (1) Smart charging connection and (2) The vehicle to grid concept. It also emphasizes managing battery security and safeguarding it from unfavorable operating conditions, including overcharging, severe discharge, over/under voltage, and thermal degradation. A humane machine interference (HMI) is developed and connected with the PLC in order to further provide reliable and efficient control monitoring of the battery parameter. Siemens S7 1200 and Siemens TIA WinCC Advanced V16.0 software are used to create and code the recommended digital battery management systems (BMS) HMI/ SCADA interface
Graphene Oxide Based Ternary Hybrid Nanocatalyst for Photocatalytic Environmental Remediation
No full textThe growing global population and modern industrialization are putting the world in danger of an energy crisis and a dramatic rise in environmental pollution. The need for sustainable clean water has increased globally, which has sparked interest in developing alternate methods for achieving this goal. Among the many commonly used techniques for environmental cleanup, visible light-responsive photocatalysis based on semiconductor materials has garnered worldwide interest as an emerging green tool that could efficiently degrade organic and inorganic pollutants into sustainable products. Therefore, in this thesis, an effort has been made to explore the synthesis and photocatalytic application of different graphene oxide (GO) based ternary hybrid nanocatalysts that can be used for visible light induced photocatalytic environmental remediation. The GO based materials were subsequently integrated with metal oxide, mixed metal oxide, etc. nanostructures to prepare Z-scheme ternary hybrid heterostructure with improved optical absorption and enhanced photoelectochemical features which are effectively used for photocatalytic environmental remediation applications. In the first part of the study, sulfur-doped reduced graphene oxide enwrapped magnetic porous nickel ferrite/copper sulfide (SrGO/NiFe2O4/CuS: GNFC) ternary hybrid nanocatalyst was constructed through a facile solvothermal-reflux route. Under exposure to visible light, the optimal GNFC-13 nanocatalyst exhibits outstanding catalytic activity for the photoreduction of 4-Nitrophenol (90.62%) and photodegradation of Tetracycline hydrochloride (94.39%), which is significantly better than that of pristine and doublet nanomaterials, respectively. The explanations for the improved photocatalytic efficiency of GNFC nanocatalysts are due to the porous structures of the magnetic NiFe2O4 and the SrGO surface, which can offer a lot of adsorption sites and, therefore, advantageous for the adsorption enrichment of harmful pollutants. Additionally, in situ photocatalytic degradation and adsorption enrichment working together synergistically may lead to improved pollutant removal efficacy. The Raman and XPS analytical techniques verified the formation of sulfur doped reduced graphene oxide in the GNFC nanocatalyst. The free-radical trapping studies, terephthalic acid test, and nitroblue tetrazolium test disclosed that h+, OH•, e−, and •O2− are cardinal reactive species in the photocatalytic system. The developed Z-scheme charge transfer channelization system of GNFC nanocatalyst has led to the increase of catalytic activity due to the effective photoinduced carrier separation, wider photoabsorption range, high hole oxidation capacity, and high electron reduction power. In the second part, hematite nanoparticles decorated nitrogen-doped reduced graphene oxide/graphitic carbon nitride (NrGO/α-Fe2O3/g-C3N4: NGCF) ternary hybrid nanocatalyst was effectively synthesized using a facile thermal treatment approach followed by calcination. The ternary hybrid nanocatalytic materials exhibited distinct structural, compositional, as well as optoelectrical characteristics, which include high crystallinity, surface exposed reactive site, nanoscale interfacial contact, strong absorption in visible region, fast migration of charge carriers and high resistance to recombination. The nitrogen doping in reduced graphene oxide was confirmed from Raman and XPS analyses. The optimal NGCF-10 nanocatalyst exhibited excellent photocatalytic performance towards Cr(VI) photoreduction (95%) and 2,4-Dinitrophenol photodegradation (88%). Radical trapping experiments suggested the vigorous formation of reactive e−, •O2−, h+ and OH• radicals in aqueous suspension of the NGCF nanocatalyst, which play a pivotal role in the photocatalytic system. The Z-scheme charge transfer channelization mechanism was accepted for the enhanced performance of the NGCF ternary hybrid nanocatalyst system. In the last part of the study, a ZnBi2O4/ZIF-67 derived hollow Co3O4 decorated reduced graphene oxide (rGO/ZnBi2O4/ZIF-Co3O4: ZCG) ternary hybrid nanocatalyst was fabricated through a facile thermal treatment approach. The optimal ZCG-4 heterojunction demonstrated exceptional catalytic effectiveness for the photocatalytic reduction of Cr(VI) (97.4%) and photocatalytic degradation of Rhodamine B (92.5%) when exposed to visible radiation, which is much superior than pristine and doublet nanohybrids. The improved photocatalytic activity may be attributed to the beneficial synergistic interaction between the rGO, ZnBi2O4, and ZIF-Co3O4 nanocomponents in the nanohybrid. The radical trapping studies disclosed that OH•, h+, e−, and •O2− are key reactive species in the photocatalytic system. Based on the data from the various experiments, we infer that the as-prepared ZCG nanocatalyst functions via a Z-scheme charge transfer channelization mechanism, exhibiting a significant suppression of the photogenerated electron-hole pairs charge recombination. In conclusion, the work presented in this thesis unlocks opportunities for energy and material efficient nanocatalysts for photocatalytic environmental remediation applications using GO based nanohybrid materials