415 research outputs found
Fading correlation of co-located transmitters
No full textFading or attenuation of a signal due to environment is a phenomenon often encountered in wireless communications. It is expected that co-located transmitters i.e. transmitters placed very close to each other show a high signal fading correlation due to the presence of similar fading environment. In this thesis, we present an experimental study of this phenomenon. Correlation of received signal strengths obtained from co-located transmitters in dynamically varying environments indicate that the large scale signal variations (shadow fading) are highly correlated while the small scale variations (multipath or fast fading) show a low correlation. Highly correlated large scale variations suggest a presence of same large shadowing elements in the transmit-receive path while a low correlation among the multipath variations is due to mutual coupling between the antennas at very close distances. This has two implications: it suggests that shadow fading variations can serve as an indicator of the co-location of closely spaced transmitters while the multipath variations cannot. However, low multipath signal correlations suggest that antenna diversity could be investigated for implementation in mobile handsets.M.S.Includes bibliographical referencesby Prashant Jadha
The transformation of healthcare through AI-driven diagnostics migrant health worker deaths during covid-19: a methodological exploration and initial estimates
No full textThis chapter delves into the transformative effects of artificial intelligence (AI) on healthcare diagnostics, focusing on accuracy, efficiency, and predictability. The thorough analysis is organized around the main thematic parts. The chapter opens with an informative review of AI's role in healthcare diagnostics, laying the groundwork for understanding how AI technologies, such as machine learning and deep learning, transform medical diagnostic processes. The history of diagnostic procedures is explored, emphasizing the transition from old methods to the current era of AI-driven approaches. Finally, this chapter presents a thorough investigation into how AI-driven diagnostics impact healthcare's future. Covering present applications, problems, and future possibilities, it adds to the greater discussion of AI integration in healthcare. It emphasizes the importance of responsible and collaborative growth in this transformational subject
Low temperature laser molecular beam epitaxy and characterization of AlGaN epitaxial layers
No full textFabrication of nanoadjuvant with poly-ɛ-caprolactone (PCL) for developing a single-shot vaccine providing prolonged immunity [Corrigendum]
No full textPrashant CK, Bhat M, Srivastava SK, et al. Int J Nanomedicine. 2014;9:937–950.On page 937, the author affiliations have been listed incorrectly. The correct author list is as follows:Chandravilas Keshvan Prashant1Madhusudan Bhat2Sandeep Kumar Srivastava2Ankit Saxena3Manoj Kumar4Amar Singh3Mohammed Samim5Farhan Jalees Ahmad6Amit Kumar Dinda21Faculty of Engineering and Interdisciplinary Sciences, Jamia Hamdard, New Delhi, India; 2Department of Pathology, 3Department of Transplant Immunology and Immunogenetics, All India Institute of Medical Sciences, New Delhi, India; 4Centre for Biomedical Engineering, Indian Institute of Technology, New Delhi, India; 5Department of Chemistry, Faculty of Science, Jamia Hamdard, New Delhi, India; 6Department of Pharmaceutics, Faculty of Pharmacy, Jamia Hamdard, New Delhi, IndiaRead the original articl
A Five–Level PWM Inverter for Hybrid PV/Fuel Cell/Battery Standalone Power System
No full textRenewable energy sources (RES) has found attention of power system researchers as alternate energy sources recently. On the other hand RES based generation has emerged as one of the best option due to global environmental concerns, especially for off-grid load locations like islands, mountains, etc., where diesel generators are main source of power generation. This paper presents an efficient photovoltaic (PV) generation integrated with multilevel inverter to ensure regulated power at user end. In order to track the maximum power of PV applications Perturb and observe (PO) algorithm is used which is based on the maximum power point tracking (MPPT) principle. However in PV based power generation, control problems surfaces because of large variation in irradiance round the clock. This issue is controlled by hybrid PV generation system which is application of secondary power source as battery and fuel cell integrated with PV generation unit. The DC output of standalone hybrid PV-SOFC-Battery generation system is inverted by a single-phase multilevel converter. This output of developed standalone hybrid PV-SOFC-Battery generation system is used to supply the single-phase load. The results have been verified with MATLAB/Simulink for different load applications
Elaboration of self-healing polymer membranes
No full textL'objectif de cette thèse est d'élaborer et de développer un type de membranes polymères qui peuvent se réparer de manière autonome en cas de fissures. Si elles ne sont pas détectées, ces fissures peuvent poser des problèmes notamment pour des applications médicales. Dans une première partie, une membrane polymère dynamique à base de micelles de copolymère tribloc ABA a été préparée. Le bloc "A" est représenté par le poly (styrene-co-acrylonitrile), copolymère bloc mécaniquement robuste, et un bloc "B" relativement mou et souple, le poly (ethylene oxide). Lorsqu'une pression est appliquée à la membrane, sa morphologie peut être ajustée grâce à la nature compressible des micelles, ainsi que les ponts dynamiques intermicellaires. Une gamme de porosités accessible peut être régulée par la pression et de manière à contrôler la performance de filtration. La même nature dynamique a également été utilisée pour montrer une réparation autonome entrainée par la pression. L'efficacité du processus de réparation dépend de la taille des fissures, de la valeur de pression et de la durée d'application de la pression. En utilisant la propriété d'auto-réparation de la membrane ci-dessus, le processus « Direct Mode Translocation » de nanoparticules a également été étudié. Quatre classes différentes de nanoparticules ont été utilisées avec diverses propriétés intrinsèques et extrinsèques. Les conclusions de ces travaux prouvent que les caractéristiques de taille, de forme et de surface des nanoparticules ainsi que la force exercée régissent le processus de translocation. Dans une seconde partie, un revêtement 2D et 3D réversible basé sur l'auto-assemblage de micelles de copolymère dibloc constitué d'un poly (methyl methacrylate) (PMMA) et du poly (n-octadecyl methacrylate) (PODMA) blocs a été développé. L'assemblage de micelles est réalisé par l'effet "Zipper", grâce aux longues chaînes pendantes du bloc PODMA. Le même effet "Zipper" permet d'enlever facilement le revêtement par lavage dans un solvant sélectif, donnant ainsi la possibilité de modifier la surface d'un substrat plusieurs fois de manière réversible. La cristallisation à température ambiante du bloc PODMA offre la possibilité d'avoir un revêtement auto-réparable thermiquement sans affecter la morphologie globale des micelles. Enfin, une dernière partie a été conceptualisée, dans laquelle l'auto-réparation se fait par « nano-gel » encapsulés et dispersés dans une membrane. Le « nano-gel » est à base d'un copolymère hydrophile en forme d'une étoile partiellement réticulée et qui doit être synthétisée par la technique de "Reversible Addition-Fragmentation Transfer" (RAFT) polymérisation. La synthèse d'un agent RAFT avec 4 bras pour la polymérisation a été accomplie, cependant, des travaux sont encore nécessaires pour valider la voie de synthèse vers la synthèse de « nano-gel » ainsi que son application pour le processus d'auto-réparation.The objective of this thesis is to develop such kind of polymeric membranes which can repair themselves autonomously in an event of damage. Such damage in a membrane, if left undetected can pose serious health issues in some of the intended applications. In the first approach, a dynamic polymeric membrane based on ABA type triblock copolymer micelles has been prepared. The block “A” is represented by mechanically robust poly(styrene-co-acrylonitrile) copolymer while block “B” by relatively soft and flexible poly(ethylene oxide). When pressure is applied to the membrane, its morphology can be fine-tuned thanks to the compressible nature of micelles as well as intermicellar dynamic bridges. A range of porosities are accessible which can be regulated by pressure and thereby controlling the filtration performance. The same dynamic nature has also been utilized to display an effective pressure driven autonomous healing. The efficiency of healing process has been found to be dependent on the extent of damage, pressure value and time duration of application of pressure. Using the self-healing property of above membrane, “Direct Mode Translocation” of nanoparticles has also been studied. Four different classes of nanoparticles were used with varied intrinsic and extrinsic properties. The findings of the work prove that the size, shape and surface characteristics of the nanoparticles as well as the applied force govern the translocation process. In a second approach, a 2D and 3D reversible coating based on the self-assembly of micelles of diblock copolymer consisting of poly(methyl methacrylate) (PMMA) and poly(n-octadecyl methacrylate) (PODMA) blocks have been developed. The assembly of micelles is accomplished via so called “Zipper” effect, thanks to the long pendant chains of PODMA block. The same “zipper” effect plays the role of removing the coating easily by washing in a selective solvent, thus giving the ability to alter the surface of substrate for many times in reversible manner. The room temperature crystallization of PODMA block provides huge implications for a thermally assisted self-healing coating without affecting the global micelle morphology. Finally, another approach has been conceptualized in which self-healing occurs via encapsulated nano-gel dispersed within a membrane. The nano-gel is based on a partially crosslinked hydrophilic star shaped block copolymer which has to be synthesized by “Reversible Addition-Fragmentation Transfer” (RAFT) polymerization technique. The synthesis of a 4- arm RAFT agent for polymerization has been accomplished however ; a substantial amount of work is still needed to validate the synthetic route towards the nano-gel synthesis as well as its further application for the self-healing process
Computational electronic structure studies of novel condensed matter phases
No full textThis dissertation compiles the bulk of my work as a PhD student in the research group of Professor Prashant K. Jain at University of Illinois at Urbana-Champaign. My research was exclusively in the field of theoretical chemistry and materials science: I employed high-performance computing tools to perform electronic structure investigations of novel crystalline materials synthesized, some for the very first time, in the group. My placement in the experimentally-focused Jain group afforded multiple opportunities in which the discoveries of my fellow group members prompted me to conduct stand-alone or collaborative theoretical investigations of new nanomaterials. A summary of the experimental backdrop to my work is presented in Chapter 1, along with a description of the theoretical methods that were the mainstay of my PhD research. Chapter 2 presents work in which my density functional theory (DFT) calculations improved our understanding of the metastability of a previously unobserved vacancy ordering in a Cu2Se. Chapter 3 presents a different direction of investigations that we conducted on Cu2Se, this time into its superionic properties. The nucleation, kinetics, and correlation of lattice strain to the order-disorder superionic phase transition were explored through a combination of transmission electron microscopy and DFT. The correlation between lattice strain and superionicity is expanded upon in Chapter 4 where Prashant and I developed a theoretical basis on which to understand compressively strain-stabilized superionicity in Cu2Se and Li2Se. Chapter 5 shifts away from Cu2Se on to HgSe. Additionally, the focus changes from the structure and transport of cations to the structure and transport of electrons, specifically the electron-conducting surface states found in topological phases of matter. Bulk band-structure calculations and charge density character analysis that I carried out led us to hypothesize that a hexagonal phase of HgSe newly-synthesized bny the Jain group was a 3-D topological insulator. The unique topological surface states (TSS) of HgSe and their dependence on strain, crystallographic symmetry, and surface faceting are determined by DFT and presented in Chapter 6. Particularly, the effect of lattice strain on the dispersion and spin texture circles back to the central theme in the studies of super-ionic crystals: that small amounts of strain can significantly alter the charge transport properties of a material.Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2022-05-01The student, Daniel Dumett Torres, accepted the attached license on 2020-04-21 at 14:56.The student, Daniel Dumett Torres, submitted this Dissertation for approval on 2020-04-21 at 15:04.This Dissertation was approved for publication on 2020-04-24 at 13:06.DSpace SAF Submission Ingestion Package generated from Vireo submission #15022 on 2020-08-25 at 17:40:29Made available in DSpace on 2020-08-27T00:49:58Z (GMT). No. of bitstreams: 2
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Zalmoxis muelleri
No full textZalmoxis muelleri new name Zalmoxis neoguinensis Müller, 1917, p. 253, 256–258, figs. 3–5 [junior secondary homonym of Euzalmoxis neoguinensis Roewer, 1915]; Roewer, 1923, p. 90, fig. 87 a–b.; Goodnight & Goodnight, 1957, p. 81–83. Gagirius neoguinensis [partim.]: Roewer, 1949 a, p. 28. Record. *Sattelberg, Wilhelmshafen, New Guinea [Madang, Papua New Guinea]; other unspecified localities in New Guinea. Etymology. Our replacement name honors the original author of this species, Adolf Müller.Published as part of Sharma, Prashant P., Kury, Adriano B. & Giribet, Gonzalo, 2011, Zalmoxidae (Arachnida: Opiliones: Laniatores) of the Paleotropics: a catalogue of Southeast Asian and Indo-Pacific species, pp. 37-58 in Zootaxa 2972 on pages 49-50, DOI: 10.5281/zenodo.20662
Designing order–disorder transformation in high-entropy ferritic steels.
No full textOrder–disorder transformations hold an essential place in chemically complex high-entropy ferritic steels (HEFSs) due to their critical technological application. The chemical inhomogeneity arising from mixing of multi-principal elements of varying chemistry can drive property altering changes at the atomic scale, in particular short-range order. Using density-functional theory-based linear-response theory, we predict the effect of compositional tuning on the order–disorder transformation in ferritic steels—focusing on Cr–Ni–Al–Ti–Fe HEFSs. We show that Ti content in Cr–Ni–Al–Ti–Fe solid solutions can be tuned to modify short-range order that changes the order–disorder path from BCC-B2 (Ti atomic-fraction = 0) to BCC-B2-L21 (Ti atomic-fraction > 0) consistent with existing experiments. Our study suggests that tuning degree of SRO through compositional variation can be used as an effective means to optimize phase selection in technologically useful alloys.This article is published as Singh, Prashant, and Duane D. Johnson. "Designing order–disorder transformation in high-entropy ferritic steels." Journal of Materials Research 27 (2022): 136-144. DOI: 10.1557/s43578-021-00336-w. Copyright 2021 The Author(s). Attribution 4.0 International (CC BY 4.0). DOE Contract Number(s): AC02-07CH11358. Posted with permission
Editors and Reviewers Acknowledgement, 2(2), July-December, 2018
No full textThe Journal of Medical Research and Innovation would like to thank each and every one who has helped us to review and edit the articles. As a small token of appreciation, we would like to mention the names of all the editors and reviewers in random order here who have edited or reviewed the articles for the July, 2018 issue. The list will be updated as when more reviewers review the articles.
Editors
1) Varshil Mehta2) Shakti Goel3) Krutarth Shah
4) Sergey Kozhukhov
Reviewers
1) Shakti Goel
2) Varshil Mehta
3) Mykola Khaitovych
4) Rahul Kotian
5) Hira Lal
6) Prashant Pradhan
7) Pravin Padalkar
8) Saumya Agarwal
9) Mathew Asare
10) Edith Claros
11) Surya Parajuli
12) Rajesh Sharawat
13) Nishu Tyagi
14) Pradosh Sarangi
15) Deepak Jain
16) Hamsini C
17) Vicky Varghese
18) Nishtha Agarwal
19) Ishpreet Biji
20) Tushar Kunder
21) Rushi Solanki
22) Suvendu Maji
23) Sergey Kozhukhov
24) Shaunak Ajinky
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