Engineering Commons^™

Comprehensive Mapping And Benchmarking Of Esaki Diode Performance, David John Pawlik

Theses

The tunneling-FET (TFET) has been identified as a prospective MOSFET replacement technology with the potential to extend geometric and electrostatic scaling of digital integrated circuits. However, experimental demonstrations of the TFET have yet to reliably achieve drive currents necessary to power large scale integrated circuits. Consequentially, much effort has gone into optimizing the band-to-band tunneling (BTBT) efficiency of the TFET. In this work, the Esaki tunnel diode (ETD) is used as a short loop element to map and optimize BTBT performance for a large design space. The experimental results and tools developed for this work may be used to (1) …

Construction Of Multi-Mode Fiber Modes Using Phase Masks, Alexandre Tulikumwenayo

Theses

Transverse fiber modes are the distribution of electromagnetic fields in the cross-section of an optical fiber through which light propagates in the fiber. Research is being conducted to explore the usage of fiber modes with the purpose of increasing the capacity and reach of optical fibers. Mode Division Multiplexing, an area in which reseach is being conducted with the same purpose, is a multiplexing scheme used in optical networks that maps data channels onto different modes, and multiplexes these modes into one fiber for transmission. This thesis focuses on the study of modes in multi-mode fibers, and the simulation of …

Fpga Hardware Accelerators - Case Study On Design Methodologies And Trade-Offs, Matthew V. Ryan

Theses

Previous research has shown that the performance of any computation is directly related to the architecture on which it is performed. As a result, the performance of compute intensive applications can be improved using heterogeneous systems. These systems consist of various processor architectures such as CPU, FPGA, DSP, and GPU. Individual computations can be performed in parallel on different processor architecrues within the heterogeneous system. Computations are performed by utilizing existing designs from implementation libraries. There is a lack of FPGA accelerators for use in these libraries and as such additional implementations need to be designed.

Different design methodologies for …

Research On Mppt Methods For Photovoltaic System Based On Microgrid, Jingchu Ji

Theses

This thesis introduces some basic concepts about a microgrid. Then it discusses the structure of photovoltaic system (PVS) which contains a solar panel and simplified PV models. Next, it discusses and compares different methods for Maximum Power Point Tracking (MPPT) with PVS. It presents three types of DC-DC converters -- Buck, Boost and Buck-Boost converter. This work proposes to apply a DC-DC converter of Buck-Boost type to make PVS controllable because this type of converter has the largest range for operational region so that it can get the best result on MPPT. Finally, this thesis presents a kind of new …

Detection Of Video Frame Insertion Based On Constraint Of Human Visual Perception, Lu Zheng

Theses

Recently, due to availability of inexpensive and easily-operable multimedia tools, digital multimedia technology has experienced drastic advancements. At the same time, video forgery becomes much easier and makes more difficult to validate the video content. Consequently, the origin and integrity of video can no longer be taken for granted. A methodology is developed that is capable of detecting the video frame insertion based on the constraint of human visual perception. The main idea is based on the so-called differential sensitivity. That is, that the variation of brightness of neighboring video frames has some constraint. First, the video sequence is partitioned …

Model Predictive Control For Building Temperature Regulation, Weiqiang Dong

Theses

With the rapid increase in human consumption of energy, global warming is becoming an urgent problem. According to the past research, a significant part of greenhouse gas release and electricity consumption has been connected to buildings. Heating systems are the major contributor to high energy consumption of buildings. Better methods for decreasing energy consumption of buildings should be proposed and applied.

Model predictive control is widely used in building temperature regulation. Each model predictive control has its advantage. Through the comparison of several methods, this thesis discusses their respective features. The combination of a Matlab-based modeling system CVX and model …

Non-Uniform Transmission Lines For Ultra Wideband: Design Optimisation And Interfacing To Antennas And Loads, Prasanth Moolakuzhy Narayanan

Theses

This thesis presents the electrical characterization of ultra-wideband non- uniform transmission lines (UWB NUTLs). Non-uniform transmission lines have been identified as a successful device for ultra-wideband pulse shaping, which can be designed to generate complex and arbitrary pulse shapes as an impulse response. The performance of a range of UWB NUTLs, with different substrate materials and load impedances, has been characterised. In addition, the possibility of interfacing NUTL with antennas and the filtering effect of antennas has been investigated. To characterise the NUTLs, knowledge of current literature related to NUTL designs is required. A detailed review of the literature published …