Digital Commons Network^™

A Look Into The Future Of Wireless Mobile Communication Technologies, Jisun Kim, Tugrul Unsal Daim, Timothy R. Anderson

Engineering and Technology Management Faculty Publications and Presentations

The number of wireless mobile communication service subscribers has reached 4.6 billion worldwide in 2009, and mobile revenues are expected to be over $1 trillion around 2012 according to the International Telecommunication Union (ITU) (ITU, 2010). A significant number of studies have been done to forecast the growing market and evaluate the new generation technology, the Beyond 3 Generation (B3G). However, there is no study forecasting when any of these new technologies will be commercialized. This paper presents a technical framework for forecasting the commercialization timeline of B3G technologies and provides insight on technology trajectories from 1G to 4G. The …

Biological Computation, Melanie Mitchell

Computer Science Faculty Publications and Presentations

In this article, the term biological computation refers to the proposal that living organisms themselves perform computations, and, more specifically, that the abstract ideas of information and computation may be key to understanding biology in a more unified manner. It is important to point out that the study of biological computation is typically not the focus of the field of computational biology, which applies computing tools to the solution of specific biological problems. Likewise, biological computation is distinct from the field of biologically-inspired computing, which borrows ideas from biological systems such as the brain, insect colonies, and the immune system …

Tracking Missing Drivers, James G. Strathman

TREC Project Briefs

By understanding driver absenteeism, transit providers can learn to manage it, Portland State University research suggests.

Manipulation Of Suspended Single Cells By Microfluidics And Optical Tweezers, Nathalie Neve De Mevergnies, Sean S. Kohles, Shelley R. Winn, Derek C. Tretheway

Mechanical and Materials Engineering Faculty Publications and Presentations

Chondrocytes and osteoblasts experience multiple stresses in vivo. The optimum mechanical conditions for cell health are not fully understood. This paper describes the optical and microfluidic mechanical manipulation of single suspended cells enabled by the μPIVOT, an integrated micron resolution particle image velocimeter (μPIV) and dual optical tweezers instrument (OT). In this study, we examine the viability and trap stiffness of cartilage cells, identify the maximum fluid-induced stresses possible in uniform and extensional flows, and compare the deformation characteristics of bone and muscle cells. These results indicate cell photodamage of chondrocytes is negligible for at least 20 min for laser …

Modeling Acoustic Scattering From The Seabed Using Transport Theory, Jorge Quijano, Lisa M. Zurk

Electrical and Computer Engineering Faculty Publications and Presentations

Radiative Transfer (RT) theory has established itself as an important tool for electromagnetic remote sensing in parallel plane geometries with random distributions of scatterers, and most recently it has also been proposed as a model for the propagation of elastic waves in layered ocean sediments. In this work the capabilities of this model are illustrated, as the RT method is used to predict backscattering strength from laboratory models of random media. The RT model is characterized by its flexibility on accommodating scatterers in a broad variety of sizes, shapes, and acoustic contrast relative to the background media. Additionally, this formulation …

Application Of Cuda In The Boolean Domain For The Unate Covering Problem, Eric Paul, Bernd Steinbach, Marek Perkowski

Electrical and Computer Engineering Faculty Publications and Presentations

NVIDIA’s Compute Unified Device Architecture (CUDA) is a relatively-recent development that allows to realize very fast algorithms for several Constraint Satisfaction and Computer Aided Design tasks. In this paper we present an approach to use Graphics Processing Units (GPU) and CUDA for solving Unate Covering Problem, a practical problem related to SAT. In particular we present a CUDA-enabled Petrick Function Minimizer. We compare the performance of a pipeline-processor (CPU) and a parallel processor (GPU) implementation of the matrix-multiplication method for solving unate covering problems.

Characteristics Of Transitions In Freeway Traffic, Robert L. Bertini, Soyoung Ahn

Civil and Environmental Engineering Faculty Publications and Presentations

This research seeks to understand the characteristics of transitions as freeway traffic changes from one state to another. This study addresses the features of two types of transitions; transitions near a merge and transitions along shock waves during the onsets and dissipations of queues at several freeway sites.

Individual vehicle trajectory data were analyzed for studying the transitions near a merge. The length of a transition zone was measured by analyzing the spatial changes in flow, density and speed along kinematic waves near a merge. It was found that the length of transition in terms of flow, density and speed …

Multiple Trophic Levels Fueled By Recirculation In The Columbia River Plume, Raphael M. Kudela, Alexander R. Horner-Devine, Neil S. Banas, Barbara M. Hickey, Tawnya D. Peterson, Ryan M. Mccabe, Evelyn J. Lessard, Elizabeth R. Frame, Kenneth W. Bruland, David A. Jay, Jay O. Peterson, William T. Peterson, P. Michael Kosro, Sherry L. Palacios, Maeve C. Lohan, Edward P. Dever

Civil and Environmental Engineering Faculty Publications and Presentations

Large rivers represent gateways for the transport of terrigenous and anthropogenic material to the coastal ocean. Here we document a ?700 km2 recirculation or bulge associated with the Columbia River plume that retains recently discharged river water sufficiently to create a regional bioreactor. Fueled by a fluvial nitrate source, this feature stimulated growth across three trophic levels and may buffer this gateway system during periods of increased warming and stratification that lead to decreased ocean productivity, potentially enhancing production at multiple trophic levels and enriching surfacewaters far from the river mouth.

Evolutionary Quantum Logic Synthesis Of Boolean Reversible Logic Circuits Embedded In Ternary Quantum Space Using Heuristics, Martin Lukac, Marek Perkowski, Michitaka Kameyama

Electrical and Computer Engineering Faculty Publications and Presentations

It has been experimentally proven that realizing universal quantum gates using higher-radices logic is practically and technologically possible. We developed a Parallel Genetic Algorithm that synthesizes Boolean reversible circuits realized with a variety of quantum gates on qudits with various radices. In order to allow synthesizing circuits of medium sizes in the higher radix quantum space we performed the experiments using a GPU accelerated Genetic Algorithm. Using the accelerated GA we compare heuristic improvements to the mutation process based on cost minimization, on the adaptive cost of the primitives and improvements due to Baldwinian vs. Lamarckian GA.We also describe various …

Comparing Discrete Simulation And System Dynamics: Modeling An Anti-Insurgency Influence Operation, Wayne Wakeland, Una E. Medina

Systems Science Faculty Publications and Presentations

This paper contrasts the tradeoffs of modeling the same dynamic problem at a micro scale and at a macro scale of analysis: discrete system simulation (DS) versus continuous system simulation or system dynamics (SD). Both are employed to model the influence of entertainment education on terrorist system decay, with implications for field application. Each method optimizes different design, scope/scale, data availability/accuracy, parameter settings, and system sensitivities. Whether the research served by the computer model is applied or theoretical, DS tends to be useful for understand low-level individual unit/step influences on system change over time, whereas SD tends to shine when …

System Dynamics Implementation Of An Extended Brander And Taylor-Like Easter Island Model, Takuro Uehara, Yoko Nagase, Wayne Wakeland

Systems Science Faculty Publications and Presentations

We provide a system dynamics implementation of a dynamic ecological economics model. Dynamic economic models are often constrained to use functions, such as the Cobb-Douglas function, chosen “conveniently” to allow for analytic solutions. The C-D function, however, suffers from its fixed elasticity that does not allow for the substitutability between man-made capital and natural capital to change, which is vital for economic sustainability. Using system dynamics removes this constraint and enables more realistic ecological economics models containing functions not amenable to analytic solution. The base model is the natural resource and population growth model developed by Brander and Taylor (1998) …

Developing Sustainable Life Support System Concepts, Evan A. Thomas

Mechanical and Materials Engineering Faculty Publications and Presentations

Sustainable spacecraft life support concepts may allow the development of more reliable technologies for long-duration space missions. Currently, life support technologies at different levels of development are not well evaluated against each other, and evaluation methods do not account for long-term reliability and sustainability of the hardware. This paper presents point-of-departure Sustainable System Mass (SSM) evaluation criteria for life support systems that may allow more robust technology development, testing, and comparison. An example sustainable water recovery system concept is presented.

Second-Generation International Space Station Total Organic Carbon Analyzer Verification Testing And On-Orbit Performance Results, Nicole L. Bentley, Evan A. Thomas, Michael Van Wie, Chad Morrison

Mechanical and Materials Engineering Faculty Publications and Presentations

The International Space Station (ISS) total organic carbon analyzer (TOCA) is designed to autonomously assess recovered water quality by providing an indication of total organic carbon (TOC). The current TOCA has been on the ISS since November 2008. Functional checkout and operations revealed complex operating considerations. Specifically, failure of the hydrogen (H2) catalyst resulted in development of an innovative oxidation analysis method. This method reduces activation time and limits the H2 produced during analysis, while retaining the ability to indicate TOC concentrations within 25% accuracy. Subsequent testing and comparison to archived samples returned from the station and tested on the …

Improving Robustness Of Hydrologic Parameter Estimation By The Use Of Moving Block Bootstrap Resampling, Hamid Moradkhani, Mohammad Ebtehaj, Hoshin V. Gupta

Civil and Environmental Engineering Faculty Publications and Presentations

Modeling of natural systems typically involves conceptualization and parameterization to simplify the representations of the underlying process. Objective methods for estimation of the model parameters then require optimization of a cost function, representing a measure of distance between the observations and the corresponding model predictions, typically by calibration in a static batch mode and/or via some dynamic recursive optimization approach. Recently, there has been a focus on the development of parameter estimation methods that appropriately account for different sources of uncertainty. In this context, we introduce an approach to sample the optimal parameter space that uses nonparametric block bootstrapping coupled …

The Surface Expression Of Semidiurnal Internal Tides Near A Strong Source At Hawaii. Part I: Observations And Numerical Predictions, Cedric Chavanne, P. Flament, Glenn S. Carter, M. Merrifield, D. Luther, Edward D. Zaron, K. W. Gurgel

Civil and Environmental Engineering Faculty Publications and Presentations

Observations of semidiurnal currents fromhigh-frequency radioDoppler currentmeters andmoored acoustic Doppler current profilers (ADCPs) in the Kauai Channel, Hawaii, are described and compared with two primitive equation numerical models of the tides. The Kauai Channel, separating the islands of Oahu and Kauai, is a site of strong internal tide generation by the barotropic tides flowing over Kaena Ridge, the subsurface extension of Oahu. The nature and impacts of internal tide generation in the Kauai Channel were intensively studied during the 2002–03 near-field component of the Hawaii Ocean Mixing Experiment. Comparisons of observed coherent (i.e., phase locked to the astronomical forcing)M_{2 …}

Multiharmonic Frequency Tracking Method Using The Sigma-Point Kalman Smoother, Sunghan Kim, Anindya S. Paul, Eric A. Wan, James Mcnames

Electrical and Computer Engineering Faculty Publications and Presentations

Several groups have proposed the state-space approach to tracking time-varying frequencies of multiharmonic quasiperiodic signals. The extended Kalman filter/smoother (EKF/EKS) is one of the common frequency tracking approaches seen in the literature. We introduce a multiharmonic frequency tracker based on the forward-backward statistical linearized Sigma-Point Kalman smoother (FBSL-SPKS) and compare its performance to that of the extended Kalman smoother (EKS). In all cases the FBSL-SPKS tracker outperformed the EKS tracker over a wide range of signal-to-noise (SNR) ratios. We also demonstrate its superior performance on real signals.

Automated Nanocrystal Orientation And Phase Mapping In The Transmission Electron Microscope On The Basis Of Precession Electron Diffraction, Edgar F. Rauch, Joaquin Portillo, Stavros Nicolopoulos, Daniel Bultreys, Sergei Rouvimov, Peter Moeck

Physics Faculty Publications and Presentations

An automated technique for the mapping of nanocrystal phases and orientations in a transmission electron microscope is described. It is primarily based on the projected reciprocal lattice geometry that is extracted from electron diffraction spot patterns. Precession electron diffraction patterns are especially useful for this purpose. The required hardware allows for a scanning-precession movement of the primary electron beam on the crystalline sample and can be interfaced to any older or newer mid-voltage transmission electron microscope (TEM). Experimentally obtained crystal phase and orientation maps are shown for a variety of samples. Comprehensive commercial and open-access crystallographic databases may be used …

River Influences On Shelf Ecosystems: Introduction And Synthesis, Barbara M. Hickey, Raphael M. Kudela, Jonathan Nash, Kenneth W. Bruland, William T. Peterson, P. Maccready, Evelyn J. Lessard, David A. Jay, Neil S. Banas, Antonio M. Baptista, Edward P. Dever, P. Michael Kosro, Levi Kilcher, Alexander R. Horner-Devine, Edward D. Zaron, Ryan M. Mccabe, Jay O. Peterson, Philip M. Orton, Jiayi Pan

Civil and Environmental Engineering Faculty Publications and Presentations

River Influences on Shelf Ecosystems (RISE) is the first comprehensive interdisciplinary study of the rates and dynamics governing the mixing of river and coastal waters in an eastern boundary current system, as well as the effects of the resultant plume on phytoplankton standing stocks, growth and grazing rates, and community structure. The RISE Special Volume presents results deduced from four field studies and two different numerical model applications, including an ecosystem model, on the buoyant plume originating from the Columbia River. This introductory paper provides background information on variability during RISE field efforts as well as a synthesis of results, …

Climate And More Sustainable Cities: Climate Information For Improved Planning And Management Of Cities (Producers/Capabilities Perspective), C.S.B. Grimmond, Matthias Roth, Tim R. Oke, Y. C. Au, M. Best, R. Betts, Gregory R. Carmichael, Helen Cleugh, Walter F. Dabberdt, Rohinton Emmanuel, E. Freitas, K. Fortuniak, Steven Hanna, Petra M. Klein, Laurence S. Kalkstein, C. H. Liu, Alex Nickson, David Pearlmutter, David J. Sailor, James Voogt

Mechanical and Materials Engineering Faculty Publications and Presentations

In the last two decades substantial advances have been made in the understanding of the scientific basis of urban climates. These are reviewed here with attention to sustainability of cities, applications that use climate information, and scientific understanding in relation to measurements and modelling. Consideration is given from street (micro) scale to neighbourhood (local) to city and region (meso) scale. Those areas where improvements are needed in the next decade to ensure more sustainable cities are identified. High-priority recommendations are made in the following six strategic areas: observations, data, understanding, modelling, tools and education. These include the need for more …

Initial Expansion Of The Columbia River Tidal Plume: Theory And Remote Sensing Observations, David A. Jay, Edward D. Zaron, Jiayi Pan

Civil and Environmental Engineering Faculty Publications and Presentations

Analysis of the Columbia River tidal plume using Lagrangian frontal equations provides a concise description of the evolution of frontal depth H, velocity U, reduced gravity g', and frontal internal Froude number F (sub R) . Because the estuary mouth is narrow, the initial radial plume motion is supercritical (F (sub R) > 1) for up to 12 hours. Understanding this supercritical phase is vital, because plume properties change rapidly, with strong ecosystem impacts. To analyze this expansion, analytical and numerical models (the latter with three mixing formulations) were tested. Model results are compared to synthetic aperture radar images to verify …

Development Of A Contingency Capillary Wastewater Management Device, Evan A. Thomas

Mechanical and Materials Engineering Faculty Publications and Presentations

The personal body-attached liquid liquidator (PBALL) is conceived as a passive, capillary-driven, contingency wastewater disposal device. In this contingency scenario, the airflow system on the NASA crew exploration vehicle is assumed to have failed, leaving only passive hardware and vacuum vent to dispose of wastewater. To meet these needs, the PBALL was conceived to rely on capillary action and urine wetting conditions from 0° < θadv ∼ 90°, be adaptable for both male and female use, collect and retain up to 1 L of urine, minimize splash-back, and allow continuous draining of the wastewater to vacuum while minimizing cabin air loss. A subscale PBALL test article, which was tested on NASA's reduced-gravity aircraft in April 2010, successfully demonstrated key components of this design.

Organic Particulate Matter Formation At Varying Relative Humidity Using Surrogate Secondary And Primary Organic Compounds With Activity Corrections In The Condensed Phase Obtained Using A Method Based On The Wilson Equation, James F. Pankow, E. I. Chang

Civil and Environmental Engineering Faculty Publications and Presentations

Secondary organic aerosol (SOA) formation in the atmosphere is currently often modeled using a multiple lumped "two-product" (N · 2p) approach. The N · 2p approach neglects: 1) variation of activity coefficient (i) values and mean molecular weight MW in the particulate matter (PM) phase; 2) water uptake into the PM; and 3) the possibility of phase separation in the PM. This study considers these effects by adopting an (N ·2p)pMW, approach (is a phase index). Specific chemical structures are assigned to 25 lumped SOA compounds and to 15 representative primary organic aerosol (POA) compounds to allow calculation of i …