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Articles 991 - 1020 of 2758

Full-Text Articles in Engineering

Relative Sea Level, Tides, And Extreme Water Levels In Boston Harbor From 1825 To 2018, Stefan Talke, A. C. Kemp, J. Woodruff Jun 2018

Relative Sea Level, Tides, And Extreme Water Levels In Boston Harbor From 1825 To 2018, Stefan Talke, A. C. Kemp, J. Woodruff

Civil and Environmental Engineering Faculty Publications and Presentations

Using newly-discovered archival measurements, we construct an instrumental record of water levels and storm tides in Boston (MA) since 1825. After ascertaining the 19th century datum and correcting for a 0–0.03 m bias in the modern tide-gauge record, we show that local, decadally-averaged relative sea level (RSL) rose by 0.2860.05 m since 1826, with an acceleration of 0.02360.009 mm/yr2. Tide range decreased by 5.5% between 1830 and 1910, due in large part to dredging and filling of Boston Harbor, and trended slightly upward thereafter. An evaluation of storm events since 1825 suggests that trends in flood risk are driven by …


Assessing Scrum Project Management And Teamwork In Electrical And Computer Engineering Courses, Branimir Pejcinovic, Robert B. Bass, Phillip Wong Jun 2018

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 …


A Review Of In-Situ And Remote Sensing Technologies To Monitor Water And Sanitation Interventions, Luis Andres, Kwasi Boateng, Christian Borja-Vega, Evan Thomas Jun 2018

A Review Of In-Situ And Remote Sensing Technologies To Monitor Water And Sanitation Interventions, Luis Andres, Kwasi Boateng, Christian Borja-Vega, Evan Thomas

Engineering and Technology Management Faculty Publications and Presentations

The United Nations Sustainable Development Goals (SDGs), announced in September 2015, present a vision of achieving a higher level of human health and well-being worldwide by the year 2030. The SDG targets specific to water and sanitation call for more detailed monitoring and response to understand the coverage and quality of safely managed sources. It is hoped that improved monitoring of water and sanitation interventions will reveal more cost-effective and efficient ways of meeting the SDGs. In this paper, we review the landscape of approaches that can be used to support and improve on the water and sanitation targets SDG …


Mass Accretion And Ozone Reactivity Of Idealized Indoor Surfaces In Mechanically Or Naturally Ventilated Indoor Environments, Elliott T. Gall, Donghyun Rim Jun 2018

Mass Accretion And Ozone Reactivity Of Idealized Indoor Surfaces In Mechanically Or Naturally Ventilated Indoor Environments, Elliott T. Gall, Donghyun Rim

Mechanical and Materials Engineering Faculty Publications and Presentations

In indoor environments, accretion of mass to materials may provide sites for surface chemistry that differ from those of the original material. Since indoor surfaces are a major sink of oxidant gases, surface mass accretion may impact indoor O3 chemistry. In this study, the effect of surface mass accretion on O3 surface deposition was tested by deploying cleaned borosilicate glass plates in two types of indoor environments: a mechanically ventilated ( MV ) office and a naturally ventilated ( NV ) residence located in Singapore. In each environment, seven replicate glass plates and one field blank were deployed …


Baroclinic Tidal Sea Level From Exact-Repeat Mission Altimetry, Edward Zaron Jun 2018

Baroclinic Tidal Sea Level From Exact-Repeat Mission Altimetry, Edward Zaron

Portland Institute for Computational Science Publications

A near-global model for the sea-surface expression of the baroclinic tide has been developed using exact-repeat mission altimetry. The methodology used differs in detail from other altimetry-based estimates of the open ocean baroclinic tide, but it leads to estimates which are broadly similar to previous results. It may be used for prediction of the baroclinic sea level anomaly at the frequencies of the main diurnal and semidiurnal tides, K1, O1, M2, S2, as well as the annual modulates of M2, denoted MA2 and MB2. Based on a …


Thermally Stable Super-Hydrophobic Surface Creation, Caleb Turner May 2018

Thermally Stable Super-Hydrophobic Surface Creation, Caleb Turner

Maseeh Summer Undergraduate Research Experience

Thermally stable super-hydrophobic surface coatings are critical to applications in low gravity fluid dynamics, and in particular Leidenfrost effects. The challenges of manufacturing different super-hydrophobic coatings that are thermally stable, semi-transparent, and environmentally safe at desired operating temperatures is pursued in order to explore the applications of such coatings aboard spacecraft. A catalog of surface coating manufacturing procedures is tabulated with measures for static contact angle, thermal stability, and transparency. These quantities and methods serve as a foundation for both technology applications and follow on experimentation concerning low gravity fluid mechanics at the Portland State Dryden Drop Tower lab.


A Survey Of Ride-Hailing Passengers, Steven Gehrke May 2018

A Survey Of Ride-Hailing Passengers, Steven Gehrke

PSU Transportation Seminars

In less than a decade, the ride-hailing industry, led by Uber and Lyft, has dramatically transformed the way we travel in our metro regions. Rider adoption of these on-demand mobility services has proceeded much quicker than our understanding of their impacts to our urban transportation systems. Planning for this transformation in personal mobility, which will have unintended consequences, has been made more difficult by the scarcity in meaningful data made available by these ride-hailing companies. Public agencies responsible for managing congestion and transit services are hindered in their ability to successfully plan for the integration of this emergent travel mode …


Improvement Of 802.11 Protocol On Fully Programmable Wireless Radio, Eunji Lee May 2018

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

Maseeh Summer Undergraduate Research Experience

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 Exploration Of Software Defined Radio And Gnu Radio Companion For Use In Drone-To-Drone Communication, Amanda K. H. Voegtlin May 2018

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

Maseeh Summer Undergraduate Research Experience

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 …


Automating Knife-Edge Method Of Thz Beam Characterization, Christopher Charles Faber May 2018

Automating Knife-Edge Method Of Thz Beam Characterization, Christopher Charles Faber

Maseeh Summer Undergraduate Research Experience

The goal of this project is to create a time and cost-effective solution for THz beam profiling.

The knife edge method of beam characterization is a technique to verify the intensity profile of a beam involving traveling a blade orthogonal to the beam path and measuring transmission in successive steps. We use a vector network analyzer (VNA) to measure S21 transmission from a THz source. Manual implementation of this method was time-consuming and inefficient.

Project hardware includes an Arduino, a motor shield, and a ball screw linear rail with stepper motor actuator. Software was created in LabView and data is …


Binder Free Graphene Hybridized Fe3o4 Nanoparticles For Supercapacitor Applications, Nathan D. Jansen May 2018

Binder Free Graphene Hybridized Fe3o4 Nanoparticles For Supercapacitor Applications, Nathan D. Jansen

Maseeh Summer Undergraduate Research Experience

In a world with increasing energy demands, the need for safe and mobile energy storage grows. There are a number of renewable energy sources that can be harvested, however peak demand and peak production times tend to not overlap. As the capabilities of collecting the energy grows so does the need to store the energy for later consumption. The two promising methods of storing energy are batteries or supercapacitors. Both technologies employ an electrode consisting of an active material bound to a current collector. This material participates in a redox reaction, storing charge electrochemically to later be used as energy, …


Laser-Scribed Graphene Micro-Supercapacitors, Kimi D. Owens May 2018

Laser-Scribed Graphene Micro-Supercapacitors, Kimi D. Owens

Maseeh Summer Undergraduate Research Experience

M. F. El-Kady and R. B. Kaner, “Scalable fabrication of high-power graphene micro-supercapacitors for flexible and on-chip energy storage,” Nature Communications, vol. 4, p. 1475, Feb. 2013.

Supercapacitors are electrical components that have higher energy density than regular capacitors. Currently, they are large and bulky which makes it hard to be implemented into smaller electronic devices or on-chip. In Scalable Fabrication of High-power Graphene Micro-supercapacitors for Flexible and On-chip Energy Storage, El-Kady and Kaner developed an inexpensive and reliable method for scaling down supercapacitors to be approximately 7.53 x 5.35 mm. To make the laser-scribed graphene (LSG) micro-supercapacitors, an aqueous …


Combining Algorithms For More General Ai, Mark Robert Musil May 2018

Combining Algorithms For More General Ai, Mark Robert Musil

Maseeh Summer Undergraduate Research Experience

Two decades since the first convolutional neural network was introduced the AI sub-domains of classification, regression and prediction still rely heavily on a few ML architectures despite their flaws of being hungry for data, time, and high-end hardware while still lacking generality. In order to achieve more general intelligence that can perform one-shot learning, create internal representations, and recognize subtle patterns it is necessary to look for new ML system frameworks. Research on the interface between neuroscience and computational statistics/machine learning has suggested that combined algorithms may increase AI robustness in the same way that separate brain regions specialize. In …


Learning In Bio-Molecular Computing Systems, Lauren Braun May 2018

Learning In Bio-Molecular Computing Systems, Lauren Braun

Maseeh Summer Undergraduate Research Experience

Many potential applications of biochemical computers involve the detection of highly adaptable and dynamic chemical systems, such as emerging pathogens. Current technology is expensive to develop and unique to each application, thus causing limitations in accessibility. In order to make this type of computing a realistic solution to problems in the medical field, a biochemical computer would need to be adaptable to work in a variety of applications. Banda et al. (2014) previously proposed a first dynamic biochemical system that was capable of autonomous learning. For this project we studied a framework similar to Banda’s but in two separate pieces, …


Direct Synthesis Of Graphene On Niobium And Niobium Nitride, Robin Ekeya, Otto Zietz May 2018

Direct Synthesis Of Graphene On Niobium And Niobium Nitride, Robin Ekeya, Otto Zietz

Maseeh Summer Undergraduate Research Experience

Since its isolation by mechanical exfoliation in 2004, graphene has attracted enormous interest from the scientific community not the least because of its unique physical and electronic properties. Among these, graphene’s ballistic electron transport and proximity induced superconductivity make graphene-superconductor (GS) hybrid structures a scientifically promising area.


Three Speed 3d Printed Magnetic Gear, Robert J. Rutherford May 2018

Three Speed 3d Printed Magnetic Gear, Robert J. Rutherford

Maseeh Summer Undergraduate Research Experience

Power transmission is traditionally achieved with a mechanical gear. Mechanical gears require maintenance, cause vibration, and have no overload protection. Magnetic gears offer an innovative solution to these drawbacks as they do not require regular maintenance, have no need for lubrication, create very little acoustic noise, have built in overload protection and as a result of these advantages, have a longer lifetime of operation. This research focused upon the design, assembly and demonstration of the magnetic gear concept. The research used a solid works design, 3D printed ABS plastic housing, and use of neodymium magnets and ferromagnetic iron segments.

This …


An Analysis Of Lora Low Power Technology And Its Applications, Gomathy Venkata Krishnan May 2018

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

Maseeh Summer Undergraduate Research Experience

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 …


Designing Model Experiments Around Harriet Tubman Middle School, Ryan Crist, Sarah Smith, Greg Sakradse, Ryan Scott May 2018

Designing Model Experiments Around Harriet Tubman Middle School, Ryan Crist, Sarah Smith, Greg Sakradse, Ryan Scott

Maseeh Summer Undergraduate Research Experience

Air quality is of concern in densely populated areas and especially near sources of inefficiently exhausted fossil fuel such as near the highway. Harriet Tubman middle school in North Portland, Oregon is situated alongside highway 5. Here, model experiments are designed and proposed to observe the instantaneous flow fields reflect modifications. LIDAR data was used to model the school and surrounding topography three-dimensionally in order to construct a model school and surrounding area from laser cut cardboard with a surface smoothed with paper mache. This model will be placed in the Portland State University wind tunnel; transport of mean and …


Ozone Removal Efficiency And Surface Analysis Of Green And White Roof Hvac Filters, Omed A. Abbass, David Sailor, Elliott T. Gall May 2018

Ozone Removal Efficiency And Surface Analysis Of Green And White Roof Hvac Filters, Omed A. Abbass, David Sailor, Elliott T. Gall

Mechanical and Materials Engineering Faculty Publications and Presentations

Heating, ventilation, and air-conditioning ( HVAC ) system filters from a commercial building were tested for their ability to remove ozone from intake air. Filters were taken from rooftop HVAC systems installed for two months: one located on a white membrane roof and the other on a vegetated green roof. One new, unused filter sample was tested as a reference. Samples from these filters were exposed to ozonated air streams at 40 and 120 ppb and relative humidity levels of 30% and 70%. Filter surfaces were analyzed with a scanning electron microscope to observe the structure and composition of the …


Analysis Of The Contribution Of Transportation And Land Use To Citizen Perceptions Of Livability, Rebecca Lewis May 2018

Analysis Of The Contribution Of Transportation And Land Use To Citizen Perceptions Of Livability, Rebecca Lewis

PSU Transportation Seminars

What is livability? How does the built environment influence resident perceptions of livability? Although livability is a broadly used term and a key goal in land use and transportation plans at the state level, it is unclear whether residents think their neighborhoods are livable and what contributes to their perception of livability. The purpose of the project was to understand how Oregonians, in neighborhoods of varying densities and within Metropolitan Planning Organizations (MPOs), perceive livability at the nexus of transportation and land use. We sought to understand how residents define and perceive livability in three different MPOs in the state: …


Bond-Type Cfrp Anchorage System For Prestressed Concrete Applications, Yasir Saeed, Franz Rad, Salam Al-Obaidi May 2018

Bond-Type Cfrp Anchorage System For Prestressed Concrete Applications, Yasir Saeed, Franz Rad, Salam Al-Obaidi

Student Research Symposium

High tensile strength, adjustable and high modulus of elasticity, high strength-to-weight ratio, and non-corrosiveness are great features which have made Fiber Reinforced Polymer (FRP) very attractive to engineers. Prestressed concrete applications require high strength prestressing material that could apply and maintain effective compressive force to concrete members. Although FRPs, especially Carbon FRP (CFRP), have the desired strength, no efficient system for its anchorage to concrete has been devised yet. This paper presents an experimental evaluation on new bond-type CFRP anchors. A total of eleven samples were prepared and tested. The CFRP rods were 0.375 in. and 0.50 in. diameter. The …


Radiation Source Localization By Using Backpropagation Neural Network, Jian Meng, Christof Teuscher, Walt Woods May 2018

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 …


Coastal Bridges Subjected To Waves: Analysis And Quantification Of Forces, Alaa Waleed Hameed, Thomas Schumacher May 2018

Coastal Bridges Subjected To Waves: Analysis And Quantification Of Forces, Alaa Waleed Hameed, Thomas Schumacher

Student Research Symposium

Coastal bridges can be exposed to significant wave forces during hurricane events. This research is studying the parameters that govern the structural response through data analysis of a large experimental data set. This data set was generated by testing a heavily-instrumented 1:5-scale bridge superstructure model, which was modeled after the I-10 Bridge over the Escambia Bay, under various wave conditions and water levels in a large wave flume. A unique aspect of the model is that the flexibility of the substructure can be adjusted to represent different types of bridge support systems. This poster discusses the first part of the …


Apprehensive Drought Characteristics Over Iraq: Results Of A Multidecadal Spatiotemporal Assessment, Maysoun Ayad Hameed, Ali Ahmadalipour, Hamid Moradkhani May 2018

Apprehensive Drought Characteristics Over Iraq: Results Of A Multidecadal Spatiotemporal Assessment, Maysoun Ayad Hameed, Ali Ahmadalipour, Hamid Moradkhani

Student Research Symposium

Drought is an extreme climate phenomenon that happens slowly and periodically threatens the environmental and socio-economic sectors. Iraq is one of the countries in the Middle East that has been dealing with serious drought-related issues in the 21st century. Here, we investigate meteorological drought across Iraq from 1948 to 2009 at 0.25◦ spatial resolution. The Standardized Precipitation Evapotranspiration Index (SPEI) has been utilized as a multi-scalar drought index accounting for the effects of temperature variability on drought. Four of the main characteristics of drought including extent, intensity, frequency and duration are studied and the associated spatiotemporal patterns are investigated for …


Biochemical Reservoir Computing, Hoang Nguyen, Christof Teuscher May 2018

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 …


Concrete Beams With Fully Corroded Steel Repaired With Cfrp Laminates, Needa M. Lingga, Yasir Saeed, Franz Rad, Anas Yosefani May 2018

Concrete Beams With Fully Corroded Steel Repaired With Cfrp Laminates, Needa M. Lingga, Yasir Saeed, Franz Rad, Anas Yosefani

Student Research Symposium

This research focused on concrete beams with voids simulating beams with fully corroded steel that were repaired with CFRP laminates. The experimental program included testing five, approximately one- third-scaled simply supported rectangular concrete beams. The aim was to investigate the extent of improvement by CFRP to flexural and shear capacity of beams that contain fully corroded steel bars, simulated by voids. Load carrying capacity, deflection, and ductility were measured and compared. Test results showed that one layer of CFRP increased the load capacity to slightly higher than the typical code-designed RC beam, and two layers of CFRP increased it by …


Using Reservoir Computing To Build A Robust Interface With Dna Circuits In Determining Genetic Similarities Between Pathogens, Christopher Neighbor, Christof Teuscher May 2018

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 …


Wideband Absorber Characterization Using Coaxial Airline And Electromagnetic Simulation, Ha Tran, Thanh Le, Branimir Pejcinovic May 2018

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. …


Toward Understanding Pu And Peou Of Technology Acceptance Model, Nayem Rahman May 2018

Toward Understanding Pu And Peou Of Technology Acceptance Model, Nayem Rahman

Student Research Symposium

Technology Acceptance Model (TAM) is considered one of the most popular models used in Information System (IS) research. Fred Davis developed this model as part of his doctoral research at MIT in 1986. Since then this model has been widely used in IS research and other disciplines. Two main components of TAM are Perceived Usefulness (PU) and Perceived Ease of Use (PEOU). This model allowed researchers to plug-in external factors to these two components. Researchers have used a variety of external factors to draw relationships between these two internal factors of TAM model. However, most of the research used these …


Business Model Innovation: Review Of The Concept, Importance, Classifications, And Elements, Ahmed Alibage, Mark Ahn May 2018

Business Model Innovation: Review Of The Concept, Importance, Classifications, And Elements, Ahmed Alibage, Mark Ahn

Student Research Symposium

The research trend on business models continues to surge, foreseeing them as the future blueprint to create and sustain competitive advantages, as well as the major driver that guides the strategic renovation efforts of businesses all over the world. In this research, we intensively review the literature on the business model regarding the concept emergence, theoretical background, definitions, importance, classifications, and the structure of the elements. Our interest is in gaining a better understanding of how to innovate a business model that can lead to create and sustaincompetitive advantages. Based on our findings, the literature to date lacks the systematic …