Engineering Commons^™

Zenneck Waves In Decision Agriculture: An Empirical Verification And Application In Em-Based Underground Wireless Power Transfer, Usman Raza, Abdul Salam

Faculty Publications

In this article, the results of experiments for the observation of Zenneck surface waves in sub GHz frequency range using dipole antennas are presented. Experiments are conducted over three different soils for communications distances of up to 1 m. This empirical analysis confirms the existence of Zenneck waves over the soil surface. Through the power delay profile (PDP) analysis, it has been shown that other subsurface components exhibit rapid decay as compared to the Zenneck waves. A potential application of the Zenneck waves for energy transmission in the area of decision agriculture is explored. Accordingly, a novel wireless through-the-soil power …

On-Site And External Energy Harvesting In Underground Wireless, Usman Raza, Abdul Salam

Faculty Publications

Energy efficiency is vital for uninterrupted long-term operation of wireless underground communication nodes in the field of decision agriculture. In this paper, energy harvesting and wireless power transfer techniques are discussed with applications in underground wireless communications (UWC). Various external wireless power transfer techniques are explored. Moreover, key energy harvesting technologies are presented that utilize available energy sources in the field such as vibration, solar, and wind. In this regard, the Electromagnetic(EM)- and Magnetic Induction(MI)-based approaches are explained. Furthermore, the vibration-based energy harvesting models are reviewed as well. These energy harvesting approaches lead to design of an efficient wireless underground …

Numerical And Analytical Modeling To Determine Performance Trade-Offs In Hydrogel-Based Ph Sensors, Piyush Dak, Muhammad Ashraful Alam

Birck and NCN Publications

Hydrogel based pH sensors are promising candidates for implantable sensors due to their low-cost and biocompatibility. Despite their commercial potential and numerous theoretical/experimental reports, the trade-offs between different performance parameters are not well understood, and explicitly stated. In this work, we develop a numerical and analytical framework to show that there is a fundamental trade-off between the performance parameters i.e. sensitivity/dynamic range vs. response-time/response-asymmetry in hydrogel sensors under constrained swelling conditions. Specifically, we consider the effect of the gel parameters, such as the ionizable group density ( N_f) and its dissociation constant ( K_a), on the …

Computational Electronics For The 21st Century: Reflections On The Past, Present, And Future, Mark S. Lundstrom

Department of Electrical and Computer Engineering Faculty Publications

The author’s career has coincided with the development of numerical simulation into an essential component of semiconductor device technology research and development. We now have a sophisticated suite of simulation capabilities along with new challenges for 21st Century electronics. This talk presents a short history of the field and a description of the current state of the art, but it concentrates on lessons learned and thoughts about how computational electronics can continue to contribute effectively to the development of new electronic device technologies. The author will argue that electronics is changing, and that computational electronics can play a key role …

Two-Dimensional Layered Mos2 Biosensors Enable Highly Sensitive Detection Of Biomolecules, Joonhyung Lee, Piyush Dak, Yeonsung Lee, Heekyeong Park, Woong Choi, Muhammad Ashraful Alam, Sunkook Kim

Birck and NCN Publications

We present a MoS₂ biosensor to electrically detect prostate specific antigen (PSA) in a highly sensitive and label-free manner. Unlike previous MoS₂-FET-based biosensors, the device configuration of our biosensors does not require a dielectric layer such as HfO₂ due to the hydrophobicity of MoS₂. Such an oxide-free operation improves sensitivity and simplifies sensor design. For a quantitative and selective detection of PSA antigen, anti-PSA antibody was immobilized on the sensor surface. Then, introduction of PSA antigen, into the anti-PSA immobilized sensor surface resulted in a lable-free immunoassary format. Measured off-state current of the device …

Nanoscale Contacts Between Semiconducting Nanowires And Metallic Graphenes, Seongmin Kim, David B. Janes, Sung-Yool Choi, Sanghyun Ju

Birck and NCN Publications

Metal–semiconductor (M–S) junctions are important components in many semiconductor devices, and there is growing interest in realizing high quality M–S contacts that are optically transparent. In this paper, we present our investigations into the characteristics of M–S junction in a semiconducting ZnO nanowire that was directly grown on a multilayer graphene film (MGF). The synthesized nanowires were fabricated into two-terminal devices with MGF as one contact and Al as the other contact. By comparison with devices employing Al contacts at both ends, the nanowire resistivity and specific contact resistivity of the MGF–nanowire contact can be extracted. The extracted specific contact …

Lithium-Based Battery System Management And Balancing, William Joel Schmidt Iii

Purdue Polytechnic Masters Theses

This thesis builds upon previous work completed for the design and evaluation of active lithium battery system management. Simulations were performed to provide a comparison for the hardware that was designed, built, and tested. An analysis of the simulation and hardware results was completed to support or disprove the initial hypothesis. A DC-DC converter was used as the source for the balancing current. Lithium polymer batteries with a 5Ah capacity were used for testing the designed hardware. The findings showed that there is a reduction in the system voltage swing during balancing as well as less time taken to decrease …

Miniature Mass Spectrometry: Rf Amplitude Control System Design, Matthew Allen Kirleis

Purdue Polytechnic Masters Theses

This thesis covers the methods used to construct and characterize a custom digital RF amplitude control system. Many types of mass spectrometers exist, but few have been miniaturized as much as the Mini instruments developed at Purdue University. The goal of this research was to improve upon an earlier amplitude control system consisting of analog circuits first implemented in the Mini 11.5 mass spectrometer developed at Purdue University.

A custom set of control and data acquisition electronics were developed for testing the digital and analog control systems in a Mini 11.5 mass spectrometer chassis. A MATLAB Simulink simulation was done …

Mechatronics Application To Solar Tracking, Danny L. Rodriguez Jr

Purdue Polytechnic Directed Projects

The purpose of this was to design and implement a two-axis solar tracking system utilizing the National Instruments C-Rio real time controller. In order to accomplish this a prototype was modeled in CAD. This prototype used two 12 V DC motors to change a solar panel's rotation and tilt based on feedback data from three cadmium sulfide photoresistors. This configuration was chosen for its ability to create both a left-right rotational and an up/down tilt differential. In Addition this approach uses National Instruments Labview to control a solar tracking system. Using Labview add uniqueness to this project by adding a …

Electric Motor & Power Source Selection For Small Aircraft Propulsion, Jeremy Fehrenbacher, David L. Stanley, Mary E. Johnson Dr., Jeffrey Honchell

Purdue Polytechnic Directed Projects

The research conducted in this project is on electrical propulsion in aviation. A Cessna 172K aircraft with a Lycoming O-320-E2D piston engine serves as a baseline measurement. Investigation of the components required for electrical flight is performed, and components are selected based on market availability and operational performance criteria.

This research focuses on electrical propulsion in the aviation industry, and is tailored to aircraft within the General Aviation sector leading to the following research question: Can current electric motor and battery technologies conceptually support flight operations for a Cessna 172K in terms of aircraft performance criteria?

The results explore the …

Using Smartphones For Indoor Navigation, Benjamin Thomas Loulier

Purdue Polytechnic Masters Theses

This directed projet is about the use of smartphones for indoor navigation.

Nowadays, indoor navigation is a real challenge, we are all familiar with the multiple applications of GPS based navigation but all these applications cannot be transfered in an indoor environment as we cannot receive a GPS signal inside.

The document is composed of three different parts related to indoor navigation using smartphones. The first part presents an inertial positioning system for pedestrians walking in an indoor environment, this system is implemented on an iPhone 4. In the second part we introduce a positioning system using RFID tags scattered …

Design Concepts Of Terahertz Quantum Cascade Lasers: Proposal For Terahertz Laser Efficiency Improvements, Tillmann Kubis, Saumitra Raj Mehrotra, Gerhard Klimeck

Birck and NCN Publications

Conceptual disadvantages of typical resonant phonon terahertz quantum cascade lasers 􏰎THz-QCLs􏰍 are analyzed. Alternative designs and their combination within a concrete device proposal are discussed to improve the QCL performance. The improvements are 􏰎1􏰍 indirect pumping of the upper laser level, 􏰎2􏰍 diagonal optical transitions, 􏰎3􏰍 complete electron thermalization, and 􏰎4􏰍 materials with low effective electron masses. The nonequilibrium Green’s function method is applied to predict stationary electron transport and optical gain. The proposed THz-QCL shows a higher optical gain, a lower threshold current, and a higher operation temperature. Alloy disorder scattering can worsen the QCL performance.

Detecting Stator And Rotor Winding Faults In Three-Phase Induction Machines, Jeffrey C. Robertson, Chee Mun Ong

Department of Electrical and Computer Engineering Technical Reports

The purpose of this work is to investigate the efficiency of existing methods for on-line fault detection when applied to three-phase induction motors, spc:cifically to test known theoretical calculations of harmonics developed by certain types of faults experimentally. The work involves the development of equipment and test procedures needed and research of existing methods of fault detection. The experiments are cor~ductedb y planting a fault in a test induction machine and then performing a Fast Fourier Transform (FFT) on the line current. The processed data are then compared with those from the same test machine before the fault was planted. …

Three-Dimensional Insulated Gate Bipolar Transistor (Igbt) Development, P.V. Gilbert, G.W. Neudeck

Department of Electrical and Computer Engineering Technical Reports

A new insulated gate bipolar transistor structure, the 3D-IGBT, is presented. The 3D-IGBT utilizes selective epitaxial silicon to form a top contacted anode and still retain the cellular structure of vemcally oriented devices. The 3D-IGBT , unlike other fully integrable power devices, exploits the merits of cellular structure to increase its packing density and thus reduce its on-resistance per unit area. It also eliminates the parasitic JFET resistance found in vertical IGBT's. To integrate the 3D-IGBT with low power devices, the QDI method of device isolation is also presented. QDI uses a combination of JI and DI to electrically isolate …