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C∗-Extreme Maps And Nest Algebras, Manish Kumar Dr. Jan 2023

C∗-Extreme Maps And Nest Algebras, Manish Kumar Dr.

Doctoral Theses

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Randomized Algorithms For Resource Allocation In Device To Device Communication., Subhankar Ghosal Dr. Dec 2022

Randomized Algorithms For Resource Allocation In Device To Device Communication., Subhankar Ghosal Dr.

Doctoral Theses

In device to device (D2D) communication, two users residing in close proximity can directly communicate between them, through a common channel, without the need of a base station. A pair of D2D users forms a link and a channel needs to be allocated to it. The interference relationship among the active links at time t is modelled as an interference graph g(t). To establish interference-free communication, we have to assign a channel vector C(t) and a power vector corresponding to the active links such that the required signal to interference plus noise ratio (SINR) is satisfied for each link. Since …


Constructions And Analyses Of Efficient Symmetric-Key Primitives For Authentication And Encryption., Sebati Ghosh Dr. Aug 2022

Constructions And Analyses Of Efficient Symmetric-Key Primitives For Authentication And Encryption., Sebati Ghosh Dr.

Doctoral Theses

In symmetric key cryptography there are two fundamental objectives, viz. 1. confidentiality or secrecy of message from unexpected party and 2. authentication of message which includes authenticating the source of the message as well as integrity of the message against any unwanted modification. Let us first concentrate on confidentiality. In classical symmetric key cryptography two parties, say Alice and Bob, first secretly exchange a key-pair (e, d). Later, if Alice wishes to send a secret message m ∈ M to Bob, she computes c = Ee(m) and transmits c to Bob. Upon receiving c, Bob computes Dd(c) = m and …


Morphological Network: Network With Morphological Neurons., Ranjan Mondal Dr. Aug 2022

Morphological Network: Network With Morphological Neurons., Ranjan Mondal Dr.

Doctoral Theses

Image processing with traditional approaches mainly use the tools of linear systems. However, linear approaches are not well suited and may even fail to solve problems involving geometrical aspects of the image. Thus, nonlinear geometric approaches like morphological operations are very popular in those cases. Morphological operations are nonlinear operations based on a set and lattice-theoretic methodology for image analysis that are capable of describing the geometrical structure of image objects quantitatively. It is suitable for various problems in image processing, computer vision, and pattern recognition. While solving problems with morphology, a particular structuring element is defined. Structuring elements have …


Computing Well-Structured Subgraphs In Geometric Intersection Graphs., Satyabrata Jana Dr. Jul 2022

Computing Well-Structured Subgraphs In Geometric Intersection Graphs., Satyabrata Jana Dr.

Doctoral Theses

For a set of geometric objects, the associative geometric intersection graph is the graph with a vertex for each object and an edge between two vertices if and only if the corresponding objects intersect. Geometric intersection graphs are very important due to their theoretical properties and applicability. Based on the different geometric objects, several types of geometric intersection graphs are defined. Given a graph G, an induced (either vertex or edge) subgraph H ⊆ G is said to be an well-structured subgraph if H satisfies certain properties among the vertices in H. This thesis studies some well-structured subgraphs finding problems …


Essays On The Economics Of Conflict., Ranajoy Guha Neogi Dr. May 2022

Essays On The Economics Of Conflict., Ranajoy Guha Neogi Dr.

Doctoral Theses

The thesis encompasses three chapters which provide policy-relevant insights into the domain of conflict economics. The research endeavour goes deep into exploring the underlying linkages of varied economic and non-economic factors (e.g., culture, religion and myriads of ethnic factors) leading to the multiple facets of economic outcomes. The analyses in the thesis, which fall in the realm of applied microeconomic theory, are facilitated by different tools of game theory and public economics. Although the focuses of these chapters lie in the domain of economics of conflict (and its policy implications under different situations), each chapter addresses the conflicts engendered in …


Essays In Multidimensional Mechanism Design., Kolagani Paramahamsa Dr. May 2022

Essays In Multidimensional Mechanism Design., Kolagani Paramahamsa Dr.

Doctoral Theses

This thesis analyzes three problems where a monopolistic seller is selling to an agent with multidimensional private information. While our understanding of such problems is comprehensive if the agent's private information is one-dimensional, problems with multidimensional private information are known to be ubiquitous but analytically notorious. The three chapters in this thesis make progress in understanding optimal mechanism design in such multidimensional screening problems. In the first problem, the seller is selling an object to an agent who exhibits behavioral preferences, in a departure from the standard rational models. Behavioral preferences arise because the agent is budget constrained and needs …


Efficient Handover Mechanisms For Heterogeneous Networks., Shankar Kumar Ghosh Dr. Apr 2022

Efficient Handover Mechanisms For Heterogeneous Networks., Shankar Kumar Ghosh Dr.

Doctoral Theses

In this thesis, some analytical frameworks have been developed to analyze the effect of different system parameters on handover performances in heterogeneous network (HetNet) and based on such frameworks, some efficient handover algorithms have been proposed. The study starts with an analytical framework to investigate the effect of resource allocation mechanisms, upper layer mobility management protocols (MMPs) and handover decision metrics on user perceived throughput. This analysis reveals that among other factors, handover decision metric plays a crucial role in determining user perceived throughput in HetNet. Subsequently, we develop two handover decision metrics for ultra dense networks (UDN) and unlicensed …


Essays On Social Networks, Workplace Ties And Labor Productivity., Swati Sharma Dr. Feb 2022

Essays On Social Networks, Workplace Ties And Labor Productivity., Swati Sharma Dr.

Doctoral Theses

The role of social contacts in finding jobs, career mobility and other labor market outcomes is well acknowledged both theoretically and empirically in labor economics. The existence of individuals’ social networks at their workplace is a pervasive phenomenon, leading to the widespread use of social ties for information, influence and referrals on both sides of the labor market. The central theme of this thesis is to examine the interplay of ‘off-workplace socio-economic interdependence’ and outcomes at the workplace. Understanding this interdependence has the potential to devise policies which can impact labor productivity, especially in developing countries. This thesis divided into …


Zero-Knowledge Proof, Deniability And Their Applications In Blockchain, E-Voting And Deniable Secret Handshake Protocols., Somnath Panja Dr. Feb 2022

Zero-Knowledge Proof, Deniability And Their Applications In Blockchain, E-Voting And Deniable Secret Handshake Protocols., Somnath Panja Dr.

Doctoral Theses

In this thesis, we propose a cryptographic technique for an authenticated, end-to-end verifiable and secret ballot election. Currently, almost all verifiable e-voting systems require trusted authorities to perform the tallying process except for the DRE-i and DRE-ip systems. We have shown a weaknesses in the DRE-ip system and proposed a solution. We have modified the DRE-ip system so that no adversary can create and post a valid ballot on the public bulletin board without detection. We provide security proofs to prove the security properties of the proposed scheme. We propose two methods to store these ballots using blockchain and cloud …


Many-Objective Evolutionary Algorithms: Objective Reduction, Decomposition And Multi-Modality., Monalisa Pal Dr. Jan 2022

Many-Objective Evolutionary Algorithms: Objective Reduction, Decomposition And Multi-Modality., Monalisa Pal Dr.

Doctoral Theses

Evolutionary Algorithms (EAs) for Many-Objective Optimization (MaOO) problems are challenging in nature due to the requirement of large population size, difficulty in maintaining the selection pressure towards global optima and inability of accurate visualization of high-dimensional Pareto-optimal Set (in decision space) and Pareto-Front (in objective space). The quality of the estimated set of Pareto-optimal solutions, resulting from the EAs for MaOO problems, is assessed in terms of proximity to the true surface (convergence) and uniformity and coverage of the estimated set over the true surface (diversity). With more number of objectives, the challenges become more profound. Thus, better strategies have …


Mathematical Formulations For Complex Resource Scheduling Problems., T. R. Lalita Dr. Jan 2022

Mathematical Formulations For Complex Resource Scheduling Problems., T. R. Lalita Dr.

Doctoral Theses

This thesis deals with development of effective models for large scale real-world resource scheduling problems. Efficient utilization of resources is crucial for any organization or industry as resources are often scarce. Scheduling them in an optimal way can not only take care of the scarcity but has potential economic benefits. Optimal utilization of resources reduces costs and thereby provides a competitive edge in the business world. Resources can be of different types such as human (personnel-skilled and unskilled), financial(budgets), materials, infrastructures(airports and seaports with designed facilities, windmills, warehouses’ area, hotel rooms etc) and equipment (microprocessors, cranes, machinery, aircraft simulators for …


Interplay Between Education And Identity: Inter Caste Marriages, Gendered Stream Choice And Caste Peer Effects., Komal Sahai Dr. Jan 2022

Interplay Between Education And Identity: Inter Caste Marriages, Gendered Stream Choice And Caste Peer Effects., Komal Sahai Dr.

Doctoral Theses

No abstract provided.


On Class Imbalanced Learning:Design Of Non-Parametricclassifiers, Performance Indices, And Deep Oversampling Strategies., Sankha Mullick Dr. Jan 2022

On Class Imbalanced Learning:Design Of Non-Parametricclassifiers, Performance Indices, And Deep Oversampling Strategies., Sankha Mullick Dr.

Doctoral Theses

The relevance of classification is almost endless in the everyday application of machine learning. However, the performance of a classifier is only limited to the fulfillment of the inherent assumptions it makes about the training examples. For example, to facilitate unbiased learning a classifier is expected to be trained with an equal number of labeled data instances from all of the classes. However, in a large number of practical applications such as anomaly detection, semantic segmentation, disease prediction, etc. it may not be possible to gather an equal number of diverse training points for all the classes. This results in …


Optimal Eavesdropping In Quantum Cryptography, Atanu Acharyya Dr. Jan 2022

Optimal Eavesdropping In Quantum Cryptography, Atanu Acharyya Dr.

Doctoral Theses

Quantum key distribution (QKD) has raised some promise for more secured communication than its classical counterpart. It allows the legitimate parties to detect eavesdropping which introduces error in the channel. If disturbed, there are ways to distill a secure key within some threshold error-rate. The amount of information gained by an attacker is generally quantified by (Shannon) mutual information. Knowing the maximum amount of information that an intruder can gain is important for post-processing purposes, and we mainly focus on that side in the thesis. Renyi information is also useful especially when post-processing is considered. The scope of this thesis …


Locally Dependent Natural Image Priors For Non-Blind And Blind Image Deconvolution., Kaustav Nandy Dr. Dec 2021

Locally Dependent Natural Image Priors For Non-Blind And Blind Image Deconvolution., Kaustav Nandy Dr.

Doctoral Theses

Degradation of photographic images is a common phenomenon that can occur due to several reasons. Astronomical images may be degraded due to atmospheric factors or telescope optics. Photographs taken using standard digital cameras may be blurred due to lack of focus, due to motion of the subject, due to low resolution, or due to camera shake during relatively long exposures. Often one wishes to correct for the effect of such degradation and recover the original image, and this has been a long-standing research problem in digital imaging. Effective solutions depend critically on the context of the problem and the type …


A Brief Treatise On Bayesian Inverse Regression., Debashis Chatterjee Dr. Dec 2021

A Brief Treatise On Bayesian Inverse Regression., Debashis Chatterjee Dr.

Doctoral Theses

Inverse problems, where in a broad sense the task is to learn from the noisy response about some unknown function, usually represented as the argument of some known functional form, has received wide attention in the general scientific disciplines. However, apart from the class of traditional inverse problems, there exists another class of inverse problems, which qualify as more authentic class of inverse problems, but unfortunately did not receive as much attention.In a nutshell, the other class of inverse problems can be described as the problem of predicting the covariates corresponding to given responses and the rest of the data. …


Secret Sharing And Its Variants, Matroids,Combinatorics., Shion Samadder Chaudhury Dr. Dec 2021

Secret Sharing And Its Variants, Matroids,Combinatorics., Shion Samadder Chaudhury Dr.

Doctoral Theses

The main focus of this thesis is secret sharing. Secret Sharing is a very basic and fundamental cryptographic primitive. It is a method to share a secret by a dealer among different parties in such a way that only certain predetermined subsets of parties can together reconstruct the secret while some of the remaining subsets of parties can have no information about the secret. Secret sharing was introduced independently by Shamir [139] and Blakely [20]. What they introduced is called a threshold secret sharing scheme. In such a secret sharing scheme the subsets of parties that can reconstruct a secret …


Some Nonparametric Hybrid Predictive Models : Asymptotic Properties And Applications., Tanujit Chakraborty Dr. Nov 2021

Some Nonparametric Hybrid Predictive Models : Asymptotic Properties And Applications., Tanujit Chakraborty Dr.

Doctoral Theses

Prediction problems like classification, regression, and time series forecasting have always attracted both the statisticians and computer scientists worldwide to take up the challenges of data science and implementation of complicated models using modern computing facilities. But most traditional statistical and machine learning models assume the available data to be well-behaved in terms of the presence of a full set of essential features, equal size of classes, and stationary data structures in all data instances, etc. Practical data sets from the domain of business analytics, process and quality control, software reliability, and macroeconomics, to name a few, suffer from various …


Three Essays On The Political Economics Of Conflict., Dripto Bakshi Dr. Oct 2021

Three Essays On The Political Economics Of Conflict., Dripto Bakshi Dr.

Doctoral Theses

A standard practice in the sociological and comparative-politics literature is to interpret ethnicity broadly as identity cleavages deriving from non-class categories such as language, religion, race and caste. In recent decades, conflicts between ‘ethnic’ communities, i.e., groups divided along non-class identity dimensions such as race, language, and, in particular, religion, have attained increasing salience in many countries. In response to this, a large analytical and empirical literature has developed both in political science and in political economics that seeks to explicate various aspects of this phenomenon. This thesis aims to throw light on two major aspects of ethnic conflicts. (1) …


Some Contributions To Free Probability And Random Matrices., Sukrit Chakraborty Dr. Oct 2021

Some Contributions To Free Probability And Random Matrices., Sukrit Chakraborty Dr.

Doctoral Theses

No abstract provided.


Some Topics In Leavitt Path Algebras And Their Generalizations., Mohan R. Dr. Sep 2021

Some Topics In Leavitt Path Algebras And Their Generalizations., Mohan R. Dr.

Doctoral Theses

The purpose of this section is to motivate the historical development of Leavitt algebras, Leavitt path algebras and their various generalizations and thus provide a context for this thesis. There are two historical threads which resulted in the definition of Leavitt path algebras. The first one is about the realization problem for von Neumann regular rings and the second one is about studying algebraic analogs of graph C ∗ -algebras. In what follows we briefly survey these threads and also introduce important concepts and terminology which will recur throughout.


Scaling Limits Of Some Random Interface Models., Biltu Dan Dr. Sep 2021

Scaling Limits Of Some Random Interface Models., Biltu Dan Dr.

Doctoral Theses

In this thesis, we study some probabilistic models of random interfaces. Interfaces between different phases have been topic of considerable interest in statistical physics. These interfaces are described by a family of random variables, indexed by the ddimensional integer lattice, which are considered as a height configuration, namely they indicate the height of the interface above a reference hyperplane. The models are defined in terms of an energy function (Hamiltonian), which defines a Gibbs measure on the set of height configurations. More formally, letÏ• = {Ï•x}x∈Z dbe a collection of real numbers indexed by the d-dimensional integer lattice Z d. …


On The Inertia Conjecture And Its Generalizations., Soumyadip Das Dr. Sep 2021

On The Inertia Conjecture And Its Generalizations., Soumyadip Das Dr.

Doctoral Theses

This thesis concerns problems related to the ramification behaviour of the branched Galois covers of smooth projective connected curves defined over an algebraically closed field of positive characteristic. Our first main problem is the Inertia Conjecture proposed by Abhyankar in 2001. We will show several new evidence for this conjecture. We also formulate a certain generalization of it which is our second problem, and we provide evidence for it. We give a brief overview of these problems in this introduction and reserve the details for Chapter 4.Let k be an algebraically closed field, and U be a smooth connected affine …


Commuting Isometries And Invariant Subspaces In Several Variables., Sankar T. R. Dr. Aug 2021

Commuting Isometries And Invariant Subspaces In Several Variables., Sankar T. R. Dr.

Doctoral Theses

A very general and fundamental problem in the theory of bounded linear operators on Hilbert spaces is to find invariants and representations of commuting families of isometries.In the case of single isometries this question has a complete and explicit answer: If V is an isometry on a Hilbert space â„‹, then there exists a Hilbert space Hu and a unitary operator U on â„‹u such that V on â„‹u and[ S ⊗ IW 0 0 U] ∈ B((l 2 (ℤ+) ⊗ W) ⊕ â„‹u),are unitarily equivalent, whereW = ker V∗ ,is the wandering subspace for V and S is the …


Essays On Collective Contests And Bargaining., Dhritiman Gupta Dr. Jul 2021

Essays On Collective Contests And Bargaining., Dhritiman Gupta Dr.

Doctoral Theses

This thesis consists of three theoretical essays in Microeconomics. The first two essays analyze the properties of a particular class of prize sharing rules groups may employ in a situation of a collective contest with another group, over a private good. The third essay studies a situation of multi-lateral bargaining, where a buyer wants to successfully bargain with multiple sellers, who own an input each, so that he can implement a grand project. The main focus of the thesis is to theorize about and generate hypotheses of the situations summarized above. In the first chapter, we consider a situation of …


Dealing With Classification Irregularities In Real-World Scenarios., Payel Sadhukhan Dr. Jul 2021

Dealing With Classification Irregularities In Real-World Scenarios., Payel Sadhukhan Dr.

Doctoral Theses

Data processing by the human sensory system comes naturally. This processing, commonly denoted as pattern recognition and analysis are carried out spontaneously by humans. In day to day life, in most cases, decision making by humans come without any conscious effort. From the middle of the past century, humans have shown interest to render their abstraction capabilities (pattern recognition and analysis) to the machine. The abstraction capability of the machine is ’machine intelligence’ or ’machine learning’ [87].The primary goal of machine learning methods is to extract some meaningful information from the ’data’. Data refers to the information or attributes that …


Essays In Behavioral Social Choice Theory., Sarvesh Bandhu Dr. Jul 2021

Essays In Behavioral Social Choice Theory., Sarvesh Bandhu Dr.

Doctoral Theses

This thesis comprises four essays on social choice theory. The first three essays/chapters consider models where voters follow “non-standard” rules for decision making. The last chapter considers the binary social choice model and analyzes the consequences of a new axiom. The first chapter introduces a new axiom for manipulability when voters incur a cost if they misreport their true preference ordering. The second chapter considers the random voting model with strategic voters where standard stochastic dominance strategy-proofness is replaced by strategy-proofness under two lexicographic criteria. The third chapter also considers the random voting model but from a non-strategic perspective. It …


Terrorism And Counter-Terrorism: A Game Theoretic Approach., Aditya Bhan Dr. Jul 2021

Terrorism And Counter-Terrorism: A Game Theoretic Approach., Aditya Bhan Dr.

Doctoral Theses

Microeconomic concepts are often applied to analyze the phenomenon of terrorism, and gametheoretic frameworks are commonly applied throughout the existing literature. This is unsurprising, since real-world scenarios involving strategic interactions are best formulated using game theory because such formulations not only provide deep insights into the web of incentives and disincentives within which each player operates and consequent predictive paradigms, but also enable the creation of policy architectures based on anticipation of players‟ actions and/or alteration of players‟ incentives/disincentives to encourage/discourage certain behavioural outcomes. This thesis also applies game-theoretic frameworks to analyze some issues within the domain of terrorism and …


Integrated Shift And Drift Control Of A Non-Linear Growth Process., Soham Chakraborty Dr. May 2021

Integrated Shift And Drift Control Of A Non-Linear Growth Process., Soham Chakraborty Dr.

Doctoral Theses

In the field of Quality Control (QC), the term 'control' is used to mean many different things. For example, it may refer to an isolated control action (e.g. a process adjustment), a particular type of control architecture (e.g. feedback vs. feed forward control) or even a control discipline (e.g. Deming's PDCA cycle). So will be the case here. But the exact meaning will be clear from the context.Since the development of control chart by Shewhart [1] and the method of acceptance sampling by Dodge and Romig [2] during 1920's - 1940's, the field of quality control has been greatly enriched …