Analysis and comparison of two high-gain interleaved coupled-inductor boost converters

The main objective of this thesis is to compare and analyze two different high-gain dc-dc power electronic converters based on coupled inductors and capacitor-diode multiplier cells. The idea of these converters is to integrate the solar energy with a 400V DC microgrid. DC microgrids are more efficient, less expensive, and more reliable compared to AC microgrids. They also favor the integration of renewable energy sources. With the growing need for the utilization of more renewable sources of energy, photovoltaic panels have become one of the trending technologies which convert the energy from the sun to a useable electrical power. But these panels produce a low dc output voltage which cannot directly be connected to the high voltage dc distribution of the grid. They require high-gain dc-dc converters suitable for converting the output voltage of the solar panels to the dc distribution grid voltage. The topologies studied in this thesis provide a high dc voltage gain suitable for this application. The other significant advantage of these topologies is a continuous input current which increases the effective utilization of the source. These converters can also be used in applications involving high gain dc-dc conversion such as fuel cells, and energy storage applications like ultracapacitors. In this thesis, the different operating modes of the two high-gain dc-dc converters are explained in detail. Also, the voltage and current stresses seen by the components have been derived and power loss analysis is carried out for both the topologies. Recently, GaN switches have gained popularity for their higher efficiencies at higher switching frequencies, so this thesis also makes an attempt to compare Si to GaN devices in terms of efficiency improvements for the studied converters --Abstract, page iii

Designing switches for routing in circuit-switched trees

Reconfigurable computing provides a fast and flexible solution for intensive computing processes. Thus, it acts as a bridge between software controlled and hardware based processors. The self–reconfigurable gate array (SRGA) is a reconfigurable architecture that allows fast switching between operations on a reconfigurable device. It consists of a 2-dimensional array of processing elements (PEs) connected using a binary tree structure, called a circuit-switched tree (CST). A CST is a balanced binary tree in which leaves represent processing elements (PE) and internal nodes represent switches. The PEs in the CST communicates with each other by configuring the appropriate switches in the communication path for different types of communication patterns. In this thesis, we have designed and implemented digital blocks for the routing algorithms provided by Roy et al. [RTV04] for right-oriented communication patterns for width-1 and width-w well-nested sets and width-1 multicast sets. We have extended the work and implemented the algorithm for point-to-point, right-oriented, width-w communication sets. Finally, we have introduced a multi-pattern framework, which accommodates different communication patterns. All the designs are synthesized for 0.25-micrometer technology and area, frequency, and power analyses are performed. The results show the behavior of the designs with four, eight, and 16 PEs. The results prove that the proposed framework occupies less area as compared to the sum of the areas occupied by other communication patterns discussed

Properties of Carbon Nanotubes and their applications in Nanotechnology – A Review

One of the most distinctive inventions in the world of nanotechnology is the carbon nanotube (CNT). Many scholars around the world have been studying carbon nanotubes (CNTs) over the past two decades due to their enormous potential in a variety of sectors. Single-wall CNTs with dimensions in the nanometer range are commonly referred to as carbon nanotubes. Carbon nanotubes are also known as multi-wall CNTs, which are made up of nested single-wall CNTs that are weakly bonded together in a tree ring-like structure by van der Waals interactions. Tubes having an unknown carbon wall structure and diameters smaller than 100 nanometers are also referred to as carbon nanotubes. A carbon nanotube's length is often substantially longer than its diameter, according to standard manufacturing methods. Carbon nanotubes are capable of exhibiting a variety of remarkable properties. CNTs have distinct electrical, mechanical and optical properties that have all been thoroughly investigated. The properties and applications of carbon nanotubes are the focus of this review

Study on Concurrent Operations in Extendible Hashing Involving Merging

Computer Scienc

Activity of radon (222Rn) in the lower atmospheric surface layer of a typical rural site in south India

Analysis of one year measurements of in situ radon (222Rn) and its progenies along with surface air temperature, relative humidity and pressure near to the Earth’s surface has been carried out for the first time at the National Atmospheric Research Laboratory (NARL, 13.5∘N and 79.2∘E) located in a rural site in Gadanki, south India. The dataset was analysed to understand the behaviour of radon in relation to the surface air temperature and relative humidity at a rural site. It was observed that over a period of the 24 hours in a day, the activity of radon and its progenies reaches a peak in the morning hours followed by a remarkable decrease in the afternoon hours. Relatively, a higher concentration of radon was observed at NARL during fair weather days, and this can be attributed to the presence of rocky hills and dense vegetation surrounding the site. The high negative correlation between surface air temperature and activity of radon (R = – 0.70, on an annual scale) suggests that dynamical removal of radon due to increased vertical mixing is one of the most important controlling processes of the radon accumulation in the atmospheric surface layer. The annual averaged activity of radon was found to be 12.01±0.66 Bq m−3 and 4.25±0.18 Bq m−3 for its progenies, in the study period

Architecture for data exchange among partially consistent data models

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2002.Includes bibliographical references (leaves 75-76).by Eswar Venkat Ram Prasad Vemulapalli.S.M

Difficult Denture Birds: An Easy Psychological Assessment

Individuals who present uncommon and abnormal denture problems require unusual and resourceful treatment. Because of the extreme complexity of their systemic illness, physical,psychogenic abnormalities, anatomic abnormalities and neurological disorders, these are the difficult denture birds. This article mainly describes about difficult denture birds and theirmanagement.&nbsp

Managing the Pandemic in the South Asian (SAARC) Countries

This paper explores the coronavirus pandemic response from a South Asian perspective. When their case numbers were still relatively low, the South Asian Association for Regional Cooperation (SAARC) countries adopted lockdowns at the same time or before India did. On 24 March 2020, when there were just two confirmed cases, Nepal went into lockdown, and Sri Lanka locked down on 22 March, when there were 78 cases. India locked down the day after Nepal, with all countries imposing some form of restrictions on people’s movement. This paper draws its data from the first year of the pandemic that loomed in the SAARC nations. The regional cooperation provided by SAARC has allowed the sharing of resources and a strengthening of the region’s self-reliance. Notably, the commitment made by India to ensure its neighbours are supplied with vaccines, many of these donated. The eight-member SAARC states are Afghanistan, Bangladesh, Bhutan, India, Maldives, Nepal, Pakistan, and Sri Lanka. This paper draws on the knowledge and perceptions of academics and social workers in the SAARC countries. It provides insight into the responses, impacts, vulnerabilities, and challenges faced by the region and in each specific country since the beginning of COVID-19. This paper also offers a discussion on vaccines, PPE, as well as the role of cooperation across the region. The relationship between India and the SAARC countries and its ‘neighbourhood first’ policy are also discussed

Preparation, validation and user-testing of pictogram-based patient information leaflets for hemodialysis patients

AbstractBackground: Patient information leaflets are universally-accepted resources to educate the patients/users about their medications, disease and lifestyle modification. Objectives: The objective of the study was to prepare, validate and perform user-testing of pictogram-based patient information leaflets (P-PILs) among hemodialysis (HD) patients. Methods: The P-PILs are prepared by referring to the primary, secondary and tertiary resources. The content and pictograms of the leaflet have been validated by an expert committee consisting of three nephrologists and two academic pharmacists. The Baker Able Leaflet Design has been applied to develop the layout and design of the P-PILs. Results: Quasi-experimental pre- and post-test design without control group was conducted on 81 HD patients for user-testing of P-PILs. The mean Baker Able Leaflet Design assessment score for English version of the leaflet was 28, and 26 for Kannada version. The overall user-testing knowledge assessment mean scores were observed to have significantly improved from 44.25 to 69.62 with p value <0.001. Conclusion: The overall user opinion of content and legibility of the leaflets was good. Pictogram-based patient information leaflets can be considered an effective educational tool for HD patients

Study of Atmospheric Instabilities through Radioactivity

Radon and its progeny concentration are measured at 1m height from surface of Earth in the premises of National Atmospheric Research Laboratory, Gadanki to observe the changes in activity concentration of radon particularly during instabilities that are occurring in the atmosphere. The measurements were carried out using AlphaGUARD and Alpha Progeny Meter for the measurement of radon and its progenies, respectively. It has been observed that, the changes in daily and weekly atmospheric radon levels are related to the stability or turbulence of the lower troposphere. The analysis reveals that from sunny windless days indicates growth and dissolution of the inversion layer. The study of radon concentrations during several atmospheric instabilities including period during Nilam cyclone, has shown interesting features, which are correlated with the conditions of stability or turbulence in the atmosphere