1,421 research outputs found
Ghosh, the shadow lines, and the Indian-English novel
No full textThe prizewinning author of novels, nonfiction, and hybrid texts, Amitav Ghosh grew up in India and trained as an anthropologist. His works have been translated in over thirty languages. They cross and mix a number of genres, from science fiction to the historical novel, incorporating ethnohistory and travelogue and even recuperating dead languages. His subjects include climate change, postcolonial identities, translocation, migration, oceanic spaces, and the human interface with the environment
Automatic eyeblink and muscular artifact detection and removal from EEG signals using k-nearest neighbor classifier and long hhort-term memory networks
No full textElectroencephalogram (EEG) is often corrupted with artifacts originating from sources such as eyes and muscles. Hybrid artifact removal methods often require human intervention for the adjustment of different parameters. We propose a robust method that can automatically detect and remove eyeblink and muscular artifacts from EEG using a k-nearest neighbor (kNN) classifier and a long short-term memory (LSTM) network. Our method adopts a sliding window of 0.5 s to detect and remove the artifacts from EEG. Features, such as the variance, peak-to-peak amplitude, and average rectified value, are calculated for each EEG segment to identify corrupted segments using the kNN classifier. The kNN classifier detects the presence of artifacts, after which the corresponding EEG window is forwarded to the LSTM network for artifact removal. The LSTM network is trained with the corrupted segments of 0.5 s as input and clean segments of 0.5 s as output. Our method achieved an accuracy of 97.4% in identifying corrupted EEG segments and an average correlation coefficient, structural similarity, signal-to-artifact ratio, and normalized mean squared error of 0.69, 0.76, 1.52 dB, and 0.0013, respectively, in cleaning the EEG. Our results outperformed other hybrid methods reported in the literature based on a combination of ensemble empirical mode decomposition and canonical correlation analysis, a combination of independent component analysis and wavelet decomposition, and tensor decomposition. The mean absolute error of our method is also better in comparison to other methods. Our method can be applied to single and multiple channels and does not require any tuning of parameters
ENTIRE FUNCTIONS SHARING POLYNOMIALS WITH THEIR DERIVATIVES
No full textIn this paper we study the uniqueness of entire functions sharing two polynomials with their derivatives. The results of the paper improve the corresponding results of Chang and Fang (Kodai Math.J. 25(2002), 309–320) and Lahiri-Ghosh(Present author) (Analysis ,Munich. 31(2011), 47–59)
Distributed Mechanisms for Multi-Agent Systems: Analysis and Design
No full textThere is an increasing need for multi-agent systems to operate under decentralised control regimes that support openness (individual components can enter and leave at will) and enable components representing distinct stakeholders with different aims and objectives to interact effectively. To this end, this thesis explores issues associated with using techniques from Game Theory and Mechanism Design to organise and analyse such systems. In particular, emphasis is given to distributed mechanisms in which there is distributed allocation (no single centre determines the allocation of the resources or the tasks) and distributed information (agents require information privately known by other agents in order to determine their own valuation or cost). Such mechanisms are important because, in comparison to their centralised counterparts, they are robust to a single-point failure, the computational burden can be potentially shared amongst many agents, and there is a reduction in bottlenecks since not all communication need pass through a single point. As a result, distributed mechanisms are better suited to many types of multi-agent application. To provide a grounding for the mechanisms we develop, the thesis contains a running example of a multi-sensor network scenario. In these systems, distributed allocation mechanisms are desirable since they are robust and reduce bottlenecks in the communication system. Furthermore, we show that distributed information naturally arises by deriving an information-theoretic valuation function. This scenario also gives rise to two additional requirements that are addressed within this thesis: (i) constrained capacity, whereby suppliers can only provide a limited amount of goods or services at any given time and (ii) uncertainty in task completion, whereby sensors potentially fail after they have been assigned tasks. Specifically, we focus on the \ac{vcg} mechanisms and investigate ways of extending it so as to address the requirements that arise within distributed setting in general and sensor networks. In particular, we choose the VCG as our point of departure since it is a mechanism that is efficient, individually rational and incentive compatible. Unfortunately, it is brittle in the sense that it does not conserve these desirable properties when considering the requirements that we outlined above. Therefore, we develop novel mechanisms that do. In more detail, the first part of this thesis considers two distributed allocation mechanisms --- a simultaneous auction environment and \ac{cda}. In the former, bidders place sealed bids in a number of selling auctions which are concurrently offering items. This results in a distributed allocation whereby the winner at each auction is determined by the seller conducting it. For this case, we derive the optimal strategy of the bidders using a game-theoretic approach. In the \acs{cda}, buyers and sellers, respectively, submit bids and asks continuously and the market clears when a bid is higher than an ask; meaning that the allocation is again determined in a distributed way. Furthermore, CDAs are known to yield close to efficient allocations, under certain conditions, even when utilising very simple strategies. However, in our case, we need to modify their format in order to deal with the requirement of constrained capacity. In both of these mechanisms, we study the system's loss in efficiency that ensues from distributing the allocation and find that it is in the simultaneous auction case and upto in the continuous double auction case. The second part of this thesis is concerned with designing mechanisms when agents have distributed information within the system. Such settings are more general than those more traditionally studied in that they encompass the fact that agents can potentially change their valuation or cost upon knowing a signal about the system (which they have not observed) that was hitherto unknown to them. Specifically, we first show that interdependent valuations arise naturally within a sensor network when we develop an information-theoretic valuation function. To account for this, we significantly extend the VCG mechanism in order to deal with these interdependent valuations. We then go on to develop a mechanism that can deal with uncertainty in task allocation. In both of these cases, our mechanisms are shown to be efficient, individually rational and incentive compatible. Moreover, their computational properties are studied and efficient algorithms are designed (based on linear and dynamic programming) in order to speed up the computation of the allocation problem which is generally -hard
First person – Arijita Ghosh
No full textABSTRACT
First Person is a series of interviews with the first authors of a selection of papers published in Journal of Cell Science, helping early-career researchers promote themselves alongside their papers. Arijita Ghosh is the first author on “Leucine-rich repeat-containing 8B protein is associated with the endoplasmic reticulum Ca2+ leak in HEK293 cells”, published in Journal of Cell Science. Arijita is a PhD student in the laboratory of Amal Kanti Bera at the Indian Institute of Technology Madras, Chennai, India, investigating the role of leucine-rich repeat-containing 8 proteins in cellular calcium homeostasis.</jats:p
Understanding Terrorism in the context of Global Security
No full textUnderstanding Terrorism in the context of Global Security
Author / Authors : Shreyasi Ghosh
Page no. 89-106
Discipline : Political Science/Polity/ Democratic studies
Script/language : Roman/English
Category : Research paper
Keywords: Terrorism, Violence, Threat, Global Security, Globalization
Beyond national literatures: Empire and Amitav Ghosh
No full textScholarship on the writer Amitav Ghosh has addressed issues of nationalism, postcolonial identity, ecocriticism, testimony, subalternity, and historiography. But the idea of Ghosh as an Asian American author with a particular relationship to the United States and its national mythologies, has barely been considered. In this essay, I explore this neglected aspect of Ghosh’s œuvre by looking at the idea of America in his writing and by situating his work within what I term "the Bengali American grain". Reading his work alongside that of other Bengali American writers and arguing that it is more ambitious thematically and more anti-imperialistic, I probe Ghosh’s problematic relationship with the United States, asking how his hemispheric writing continues to extend and even alter the terrain often associated with Asian American literature
A survey on denoising techniques of electroencephalogram signals using wavelet transform
No full textElectroencephalogram (EEG) artifacts such as eyeblink, eye movement, and muscle movements widely contaminate the EEG signals. Those unwanted artifacts corrupt the information contained in the EEG signals and degrade the performance of qualitative analysis of clinical applications and as well as EEG-based brain–computer interfaces (BCIs). The applications of wavelet transform in denoising EEG signals are increasing day by day due to its capability of handling non-stationary signals. All the reported wavelet denoising techniques for EEG signals are surveyed in this paper in terms of the quality of noise removal and retrieving important information. In order to evaluate the performance of wavelet denoising techniques for EEG signals and to express the quality of reconstruction, the techniques were evaluated based on the results shown in the respective literature. We also compare certain features in the evaluation of the wavelet denoising techniques, such as the requirement of reference channel, automation, online, and performance on a single channel
Market-Based Task Allocation Mechanisms for Limited Capacity Suppliers
No full textThis paper reports on the design and comparison of two economically-inspired mechanisms for task allocation in environments where sellers have finite production capacities and a cost structure composed of a fixed overhead cost and a constant marginal cost. Such mechanisms are required when a system consists of multiple self-interested stakeholders that each possess private information that is relevant to solving a system-wide problem. Against this background, we first develop a computationally tractable centralised mechanism that finds the set of producers that have the lowest total cost in providing a certain demand (i.e. it is efficient). We achieve this by extending the standard Vickrey-Clarke-Groves mechanism to allow for multi-attribute bids and by introducing a novel penalty scheme such that producers are incentivised to truthfully report their capacities and their costs. Furthermore our extended mechanism is able to handle sellers' uncertainty about their production capacity and ensures that individual agents find it profitable to participate in the mechanism. However, since this first mechanism is centralised, we also develop a complementary decentralised mechanism based around the continuous double auction. Again because of the characteristics of our domain, we need to extend the standard form of this protocol by introducing a novel clearing rule based around an order book. With this modified protocol, we empirically demonstrate (with simple trading strategies) that the mechanism achieves high efficiency. In particular, despite this simplicity, the traders can still derive a profit from the market which makes our mechanism attractive since these results are a likely lower bound on their expected returns
R v Ghosh [1982] 1 QB 1053, Court of Appeal
No full textEssential Cases: Criminal Law provides a bridge between course textbooks and key case judgments. This case document summarizes the facts and decision in R v Ghosh [1982] 1 QB 1053, Court of Appeal. The document also included supporting commentary from author Jonathan Herring.</p
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