Engineering Commons^™

Modeling Harmonic Impacts Of Electric Vehicle Chargers On Distribution Networks, Nicole Woodman, Robert B. Bass, Mike Donnelly

Electrical and Computer Engineering Faculty Publications and Presentations

As the proliferation of electric vehicles continues to grow, it is becoming important to understand the impacts that electric vehicle charging will have on distribution assets. EV chargers are non-linear, multi-state loads. This manuscript presents a design method for the modeling of EV charging units using a VHDL-AMS simulation environment, per IEEE Standard 1076.1. Voltage and current data collected from in-service EV charging stations were used to create harmonic profiles of the EV charging units. From these profiles, generalized models for both Level 2 and Level 3 EV chargers were created. These models were validated within a larger system context …

Thermal Management In 3d Ic Designs For Nano-Cmos Technologies: Analysis On Graphene- Vs. Graphite-Based Tim, Satya K. Vendra, Malgorzata Chrzanowska-Jeske

Electrical and Computer Engineering Faculty Publications and Presentations

With a high thermal conductivity of 3000-5000 W/m-K, Graphene outstands almost all materials in effective lateral heat spreading. Will introduction of 2D monolayer graphene in 3D-IC help in vertical heat conduction too? In this work, we investigate the impact of Graphene- and Graphite- -based inter-die thermal interface material (TIM) on the peak temperature of the 3D-IC. We compare configurations of additional intermediate layer (IL) of monolayer graphene, graphite and copper materials along with TIM. Simulations show a peak temperature reduction of up to 500C in GSRC benchmarks. Role of thermal conductivity and the additional IL critical thickness in peak temperature …

Automating Variation And Repeater Analysis In Physical Design Of Integrated Circuits, Subrat Mahalik

Dissertations and Theses

Rapid advancement and innovation in semiconductor research have continuously helped in designing efficient and complex integrated circuits in miniature size. As the device technology, is aggressively scaling to improve the device performance, the issues related to device interconnects, power, and reliability have become a major concern for the designers. These challenges make the design and validation of ASIC extremely complicated.

The primary idea of this work is to develop automation tools, to be used in the physical design flows to improve the efficiency of the design flow. The first tool named as variation analysis tool automates the on-chip variation modeling …

Power System Spoof Detection With A Hybrid Hardware/Software Benchmarking Framework, Keaton Dieter, Ben Mccamish, Eduardo Cotilla-Sanchez, Robert B. Bass, Scott Wallace, Xinghui Zhao

Electrical and Computer Engineering Faculty Publications and Presentations

The integration of monitoring and control networks at different voltage levels and across utility boundaries has made it harder to maintain and assess the resilience of power systems due to increasing cyber attacks. On the software side, a variety of research efforts pursue cyber protection algorithms, such as spoof detection techniques. On the hardware and firmware side, research has demonstrated the feasibility of adversarial attacks by providing an entry point at the device level. This work proposes and evaluates two detection performance metrics for a variety of cyber spoofing attacks introduced in a realistic Phasor Measurement Unit (PMU) network for …

Event Detection Using Correlation Within Arrays Of Streaming Pmu Data, Rich Meier, Ben Mccamish, Eduardo Cotilla-Sanchez, Jordan Landford, Robert B. Bass, David Chiu

Electrical and Computer Engineering Faculty Publications and Presentations

Phasor measurement units provide real-time power system monitoring. We present a data analysis method that leverages statistical correlation and analysis methods to identify power system events. This research uses archived phasor measurement unit data to show that the method is useful for detecting power system events. Results from a lighting strike case study are presented. A monitoring stratagem based on PMU clustering is discussed, and the viability of monitoring pertinent statistical parameters over various clustering schemes is demonstrated.

Adoption Of An Internet Of Things Framework For Distributed Energy Resource Coordination And Control, Tylor Slay

Dissertations and Theses

Increasing penetration of non-dispatchable renewable energy resources and greater peak power demand present growing challenges to Bulk Power System (BPS) reliability and resilience. This research investigates the use of an Internet of Things (IoT) framework for large scale Distributed Energy Resource (DER) aggregation and control to reduce energy imbalance caused by stochastic renewable generation. The aggregator developed for this research is Distributed Energy Resource Aggregation System (DERAS). DERAS comprises two AllJoyn applications written in C++. The first application is the Energy Management System (EMS), which aggregates, emulates, and controls connected DERs. The second application is the Distributed Management System (DMS), …

Short-Term Tracking Of Orientation With Inertial Sensors, Golriz Sedaghat

Dissertations and Theses

In the past several years, IMU's have been widely used to measure the orientation of a moving body over a continuous period of time. Although, inertial navigation is a common approach for estimating the orientation, it greatly suffers from the accumulation of error in the orientation estimation. Most of the current common practices apply zero velocity update as a calibration method to address this problem and improve the estimation accuracy. However, this approach requires the sensors to be stationary frequently.

This thesis introduces a novel method of calibration for estimating the elevation and bank angles of the orientation over a …

Flip-Chip (Fc) And Fine-Pitch-Ball-Grid-Array (Fpbga) Underfills For Application In Aerospace Electronics—Brief Review, Ephraim Suhir, Reza Ghaffarian

Mechanical and Materials Engineering Faculty Publications and Presentations

In this review, some major aspects of the current underfill technologies for flip-chip (FC) and fine-pitch-ball-grid-array (FPBGA), including chip-size packaging (CSP), are addressed, with an emphasis on applications, such as aerospace electronics, for which high reliability level is imperative. The following aspects of the FC and FPGGA technologies are considered: attributes of the FC and FPBGA structures and technologies; underfill-induced stresses; the roles of the glass transition temperature (T_g) of the underfill materials; some major attributes of the lead-free solder systems with underfill; reliability-related issues; thermal fatigue of the underfilled solder joints; warpage-related issues; attributes of accelerated life …

Electric Water Heater Modeling For Distributed Energy Resource Aggregation And Control, Anne E. Clarke

Dissertations and Theses

Today's utilities face new challenges due to the continually increasing penetration of residential solar and other distributed, stochastic generation sources. In order to maintain balance and stability in the grid without building costly, large-scale generation plants, utilities are turning to distributed energy resources for use in demand response programs. Demand response is a cost-efficient way to balance grid load/generation without the need for increased capital investment in traditional generation resources. Demand response programs are excellent exploiters of end-user devices that otherwise further accentuate the daily load curve and thus, add to the difficulties created by daily load peaks.

Electric water …

Dark Current Rts-Noise In Silicon Image Sensors, Benjamin William Hendrickson

Dissertations and Theses

Random Telegraph Signal (RTS) noise is a random noise source defined by discrete and metastable changes in the magnitude of a signal. Though observed in a variety of physical processes, RTS is of particular interest to image sensor fabrication where progress in the suppression of other noise sources has elevated its noise contribution to the point of approaching the limiting noise source in scientific applications.

There have been two basic physical sources of RTS noise reported in image sensors. The first involves a charge trap in the oxide layer of the source follower in a CMOS image sensor. The capture …

New Approaches For Memristive Logic Computations, Muayad Jaafar Aljafar

Dissertations and Theses

Over the past five decades, exponential advances in device integration in microelectronics for memory and computation applications have been observed. These advances are closely related to miniaturization in integrated circuit technologies. However, this miniaturization is reaching the physical limit (i.e., the end of Moore's Law). This miniaturization is also causing a dramatic problem of heat dissipation in integrated circuits. Additionally, approaching the physical limit of semiconductor devices in fabrication process increases the delay of moving data between computing and memory units hence decreasing the performance. The market requirements for faster computers with lower power consumption can be addressed by new …

Assessing Scrum Project Management And Teamwork In Electrical And Computer Engineering Courses, Branimir Pejcinovic, Robert B. Bass, Phillip Wong

Electrical and Computer Engineering Faculty Publications and Presentations

Teamwork and project management are essential skills for engineering students, as recognized in the proposed new ABET topic area 7. Our team of instructors exposes students to project management techniques at multiple levels within our undergraduate ECE program. By learning project management early and practicing it often, students improve their teamwork efficacy in projects, courses, and in their future careers. Scrum is a cyclical project management technique commonly used in high-tech industries. Scrum provides a framework that facilitates teamwork through an adaptable and incremental process. Our variant of scrum is tailored to students working on engineering projects in a higher-education …

An Exploration Of Software Defined Radio And Gnu Radio Companion For Use In Drone-To-Drone Communication, Amanda K. H. Voegtlin

Undergraduate Research & Mentoring Program

In a world that increasingly relies on automation and intelligent robotics, there is a need for drones to expand their independence and adaptability in navigating their environments. One approach to this problem is the use of wireless communication between units in order to coordinate their sensor data and build real-time maps of the environments they are navigating. However, especially indoors, relying on a fixed transmission tower to provide data to the units faces connectivity challenges.

The purpose of this research was to determine the fitness of an on-drone assembly that uses the the NI B200mini software-defined radio board and Gnu …

Improvement Of 802.11 Protocol On Fully Programmable Wireless Radio, Eunji Lee

Undergraduate Research & Mentoring Program

The growth in the number of connected device usage has led to a rapidly increased data traffic on wireless network and the demand for access to high speed and stable Internet connection is becoming more prominent. However, current off the shelf wireless cards are not programmable or observable across layers of the standard protocol stack, which leads to poor practical performance. Thus, Wireless Open Access Research Platform (WARP), a scalable wireless platform providing programmable functionality at every layer of the network stack, has been used for the real-time implementation and improvement of 802.11 protocol.

An Analysis Of Lora Low Power Technology And Its Applications, Gomathy Venkata Krishnan

Undergraduate Research & Mentoring Program

The number of Internet of Things (IoT) devices has exponentially increased in the last decade. With the increase in these devices, there is a necessity to effectively connect and control these devices remotely. Cellular technologies cannot handle this demand since they are not cost effective and easy to deploy. This is where LoRa technology comes handy. LoRa is long-range, low-power, low cost technology that supports internet of things applications. LoRa has many advantages in terms of capacity, mobility, battery lifetime and cost. It uses the unlicensed 915MHz ISM band and can be easily deployed.

This research is focused on setting …

Wideband Absorber Characterization Using Coaxial Airline And Electromagnetic Simulation, Ha Tran, Thanh Le, Branimir Pejcinovic

Student Research Symposium

With the increase in popularity of electronic devices especially the wireless devices, microwave absorber becomes more essential to reduce electromagnetic interference. A deep understanding of electromagnetic properties namely electric permittivity and magnetic permeability is required in order to fabricate, test and use microwave absorber. In this study, we focused on developing a procedure to parameterize material electromagnetic properties. We first extract material properties by placing samples inside an airline and taking measurements of scattering parameters matrix with a vector network analyzer. Air-line is the preferred transmission line medium since the traveling wave inside the airline is both TEM and confined. …

Radiation Source Localization By Using Backpropagation Neural Network, Jian Meng, Christof Teuscher, Walt Woods

Student Research Symposium

The most difficult part of the radiation localization is that we cannot use the traditional acoustic localization method to determine where the radiation source is. It’s mainly because the electromagnetic waves are totally different with the sound wave. From the expression of the radioactive intensity, we can tell that the intensity of radiation not only depend on the distance from the radiation but also related to the type of the nuclide. In general, the relationship between the intensity and the distance satisfy the inverse-square law, which is a non-linear relationship. In other words, if we can use the measurement and …

Biochemical Reservoir Computing, Hoang Nguyen, Christof Teuscher

Student Research Symposium

Reservoir computing is an emerging machine learning paradigm. Compared to traditional feedforward neural networks, the reservoir can be unstructured and recurrent and only the output layer is trained. Reservoirs can be built with various types of physical components, yet, biochemical building blocks have not been widely used. This project focuses on designing and testing a reservoir computer (RC) based on chemical reaction network (CRN). We simulated high-level CRNs in MATLAB and their complex chemical dynamics were observed over time. A CRN constructed by a network of coupled deoxyribozyme oscillators was chosen for the final RC model. The inputs of the …

Using Reservoir Computing To Build A Robust Interface With Dna Circuits In Determining Genetic Similarities Between Pathogens, Christopher Neighbor, Christof Teuscher

Student Research Symposium

As computational power increases, the field of neural networks has advanced exponentially. In particular recurrent neural networks (RNNs) are being utilized to simulate dynamic systems and to learn to predict time series data. Reservoir computing is an architecture which has the potential to increase training speed while reducing computational costs. Reservoir computing consists of a RNN with a fixed connections “reservoir” while only the output layer is trained. The purpose of this research is to explore the effective use of reservoir computing networks with the eventual application towards use in a DNA based molecular computing reservoir for use in pathogen …

Power Spectrum Prediction Of Amplified Dual-Band Lte-Advanced Signals, Xianzhen Yang

Dissertations and Theses

In wireless communication, the nonlinearity of a radio frequency (RF) power amplifier is an important issue for power amplifier designers. Since the nonlinearity is generated by the properties of physical components, it is hard to avoid it in producing power amplifiers. Power amplifier designers should know about the nonlinearity in order to compensate for it.

A two-tone test is a relatively widely used method to measure the nonlinearity of a power amplifier, which means the third order intercept point (IP3) can be measured from the two-tone test. Through the two-tone test, researchers have proposed some formulae to present what the …

Space-Angle Signal Processing Using A Modulated Scatter Array, Nasr Alkhafaji

Electrical and Computer Engineering PhD Day

A UHF signal processing technique is described in the Fourier Space-Angle domain that uses an array of scattering elements with reflection coefficients modulated at baseband. The illumination arrival angle distributes a UHF phase across the array, and the baseband modulator phase at each of the array elements determines the radiation angle of the desired scattered product. Undesired products are re-radiated in different directions. Example 1, 2 and 4 element arrays operate at 432 MHz array with 700 Hz modulation. 2 element arrays cancel one sideband, and the 4 element array cancels both the undesired sideband and 2nd order products. Reflection …

Drafting In Self-Timed Circuits, Christopher Cowan

Electrical and Computer Engineering PhD Day

Intervals between data items propagating in self-timed circuits are controlled by handshake signals rather than by a clock. The sequence of handshakes can be abstracted as the movement of “tokens”. In many self-timed designs, a trailing token will catch up with a leading token, even when it trails by thousands of gate delays. Simulations in SPICE of a simple GasP circular FIFO reveal this effect. Contrary to earlier work, we find the cause of drafting to be charge stored on an isolated node between two series transistors. This mechanism occurs in many decision gates that implement a logical AND. The …

Coaxial Magnetic Gearbox With A Flux Concentration Halbach Rotor And Consequent Pole Rotor Typology, Ho Yin Wong

Electrical and Computer Engineering PhD Day

This paper presents the performance comparison between a flux concentration and triple permanent magnet consequent pole magnetic gear rotor typology with the same 7.5:1 gear ratio. The triple permanent magnet consequent pole magnetic gear is unique in that it can create torque change through two field heterodyning pole combinations. The performance with respect to volumetric and mass torque density is considered. It is shown that the flux concentration typology can operate with a higher mass and volumetric higher torque density, even when using a low flux concentration ratio rotor.

Magnetically Geared Lead Screw, Mojtaba Bahrami Kouhshahi

Electrical and Computer Engineering PhD Day

New magnetically geared lead screw (MGLS) is proposed in this work, which relies only on magnetic loading. Therefore it can provide speed and force conversion like its mechanical counterparts, but unlike the mechanical gears, a MGLS contact-less operation enables it to operate without lubrication and it can operate with low noise, and higher efficiency. Its reliance on magnetic loading also provides overload protection. MGLS combines the concepts of two previously proposed actuators named linear magnetic gear (LMG) and magnetic lead screw (MLS). However, unlike the LMG and MLS the translator on a MGLS does not contain magnets and therefore for …

From A Locally Competitive Algorithm To Sensory Relevance Models, Walter Woods

Electrical and Computer Engineering PhD Day

This poster addresses the development of a new Machine Learning (ML) mechanism, the Sensory Relevance Model (SRM), as a means of splitting information processing tasks into two sub-tasks with more intuitive properties. Specifically, SRMs are a front-end for other ML techniques, re-mapping the input data to a similar space with significantly more sparsity, achieved through the transformation and suppression of inputs irrelevant to the task. Prior work has attempted to reveal this information for Neural Networks (NNs) either as a post-processing step via saliency maps or through a simple masking of the input achieved with a dot product (so-called ``attention'' …

Hierarchical Random Boolean Network Reservoirs, Sai Kiran Cherupally

Dissertations and Theses

Reservoir Computing (RC) is an emerging Machine Learning (ML) paradigm. RC systems contain randomly assembled computing devices and can be trained to solve complex temporal tasks. These systems are computationally cheaper to train than other ML paradigms such as recurrent neural networks, and they can also be trained to solve multiple tasks simultaneously. Further, hierarchical RC systems with fixed topologies, were shown to outperform monolithic RC systems by up to 40% when solving temporal tasks. Although the performance of monolithic RC networks was shown to improve with increasing network size, building large monolithic networks may be challenging, for example because …

Head Waves In Ocean Acoustic Ambient Noise: Measurements And Modeling, Martin Siderius, Jie Li, Peter Gerstoft

Electrical and Computer Engineering Faculty Publications and Presentations

Seismic interferometry recovers the Green’s function between two receivers by cross-correlating the field measured from sources that surround the receivers. In the seismic literature, it has been widely reported that this processing can produce artifacts in the Green’s function estimate called “spurious multiples” or the “virtual refracted wave.” The spurious multiples are attributed to the head wave and its multiples and travels in the seabed. The head wave phenomenon is shown to be observable from both controlled active sources and from ocean ambient noise and for both vertical and horizontal arrays. The processing used is a generalization of the passive …

Silicon Compilation And Test For Dataflow Implementations In Gasp And Click, Swetha Mettala Gilla

Dissertations and Theses

Many modern computer systems are distributed over space. Well-known examples are the Internet of Things and IBM's TrueNorth for deep learning applications. At the Asynchronous Research Center (ARC) at Portland State University we build distributed hardware systems using self-timed computation and delay-insensitive communication. Where appropriate, self-timed hardware operations can reduce average and peak power, energy, latency, and electromagnetic interference. Alternatively, self-timed operations can increase throughput, tolerance to delay variations, scalability, and manufacturability.

The design of complex hardware systems requires design automation and support for test, debug, and product characterization.

This thesis focuses on design compilation and test support for dataflow …

Deciphering The Rules Of Cell-To-Cell Coupling By Molecular Modeling And Simulation, Linda D. Lee

REU Final Reports

Intercellular communication is vital for quick adjustments and maintenance for cell function and development. Gap junctions are membranes channel proteins that enable this direct communication between adjacent cells throughout the body. The compatibility of connexins (Cx), which make up a gap junction, determines whether a gap junction can form. Though many studies show which connexins are compatible, the molecular basis is not known (Bai & Wang, 2014). Through computational modeling, we identify the residues that energetically contribute most favorably at the docking interface of homotypic and heterotypic combinations of Cx43, Cx46, and Cx50 gap junctions. However, due to instability of …

Associative Learning In Biochemical Networks, Yasmin S. Sepulveda

REU Final Reports

Emerging evidence suggests that biochemical networks can be modeled by exploiting their ability to learn through associative learning. This type of learning in biomolecular structures gives it a the advantage to be able to be computationally model, and condition. Associative learning in biochemical networks is a developing area of study that once understood, can further develop diagnostic applications, and be used as tools for data analysis. Although it is a open ended project the motive of this research was to find the the best method of association learning being used in current work. After reading current work three associative learning …