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Measurement And Simulation Of Parallel Plate Waveguide Structures In The Terahertz Region For Sensing And Material Characterization Applications, James Alexander Higgins Jan 2012

Measurement And Simulation Of Parallel Plate Waveguide Structures In The Terahertz Region For Sensing And Material Characterization Applications, James Alexander Higgins

Dissertations and Theses

The THz region is a burgeoning field of research with applications in spectroscopy, integrated circuit fabrication, bio-medicine, and communications. Until recently, the THz region was largely unexplored, mainly due to the technical difficulties involved in making efficient and compact sources and detectors. As these challenges are addressed, the focus of research has shifted to practical applications, such as sensing and imaging. The focus of this thesis is to investigate the characterization of parallel plate waveguide multimode propagation and periodically notched resonant structures for use in sensing and material parameter extraction applications. Broadband and narrowband measurements are presented and analyzed. Measurements …

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Memristor-Based Reservoir Computing, Manjari S. Kulkarni Jan 2012

Memristor-Based Reservoir Computing, Manjari S. Kulkarni

Dissertations and Theses

In today's nanoscale era, scaling down to even smaller feature sizes poses a significant challenge in the device fabrication, the circuit, and the system design and integration. On the other hand, nanoscale technology has also led to novel materials and devices with unique properties. The memristor is one such emergent nanoscale device that exhibits non-linear current-voltage characteristics and has an inherent memory property, i.e., its current state depends on the past. Both the non-linear and the memory property of memristors have the potential to enable solving spatial and temporal pattern recognition tasks in radically different ways from traditional binary transistor-based …

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Development Of A Nephelometry Camera And Humidity Controlled Cavity Ring-Down Transmissometer For The Measurement Of Aerosol Optical Properties, James Gregory Radney Jan 2012

Development Of A Nephelometry Camera And Humidity Controlled Cavity Ring-Down Transmissometer For The Measurement Of Aerosol Optical Properties, James Gregory Radney

Dissertations and Theses

A Nephelometry camera (NephCam) and Humidity Controlled Cavity Ring-Down Transmissometer (HC-CRDT) were developed for the determination of aerosol optical properties. The NephCams use a reciprocal geometry relative to an integrating nephelometer; a diode laser illuminates a scattering volume orthogonal to a charge coupled device (CCD). The use of a CCD allows for measurement of aerosol scattering in 2 dimensions; scattering coefficients and size information can be extracted. The NephCam's optics were characterized during a set of imaging experiments to optimize the images collected by the camera. An aperture setting of 1.6 was chosen because it allowed for the most light …

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Biosynthesis Of Marineosin, A Spiroaminal Undecylprodiginine Natural Product, Shaimaa Mohamed Salem Jan 2012

Biosynthesis Of Marineosin, A Spiroaminal Undecylprodiginine Natural Product, Shaimaa Mohamed Salem

Dissertations and Theses

Marineosins A and B are two spiroaminal-ring containing tripyrrole compounds isolated from the marine actinomycete, Streptomyces CNQ-617, and were found to possess potent and selective cytotoxic activity against leukemia and melanoma. Marineosins belong to the prodiginines class of natural products, examples of which are undecylprodiginine and streptorubin B. Unlike marineosins, prodiginines structures are characterized by the presence of fully conjugated tripyrrole nucleus linked to an alkyl chain (that lacks any oxygen). Cyclic prodiginines arise from an oxidative cyclization of the alkyl chain onto the tripyrrole, a step catalyzed by Rieske-oxygenase like enzymes such as RedG. The biosynthesis of prodiginines is …

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Distributed Solar Photovoltaic Grid Integration System : A Case Study For Performance, Ming Shen Jan 2012

Distributed Solar Photovoltaic Grid Integration System : A Case Study For Performance, Ming Shen

Dissertations and Theses

The needs to the sustainable development of electricity, energy efficiency improvement, and environment pollution reduction have favored the development of distributed generation (DG). But the problems come with increasing DG penetration in distribution networks. This thesis presents the Solar Energy Grid Integration System (SEGIS) Stage III project done by Portland General Electric (PGE), Advanced Energy, Sandia National Lab on a PGE selected distribution feeder. The feeder has six monitored commercial solar PV systems connected. The total power output from the PV systems has the potential to reach 30% of the feeder load. The author analyzes the performance of the solar …

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Electrokinetic Properties Of Lipid And Sarcoplasmic Reticulum Membranes In Aqueous Electrolyte And In The Presence Of Lipophilic Ions, Laura Elizabeth Satterfield Jan 2012

Electrokinetic Properties Of Lipid And Sarcoplasmic Reticulum Membranes In Aqueous Electrolyte And In The Presence Of Lipophilic Ions, Laura Elizabeth Satterfield

Dissertations and Theses

The purpose of this study is the characterization of the membrane-water interfaces of both sarcoplasmic reticulum membrane (SR) and charged lipid bilayers under varied properties of the surrounding aqueous solution. In this work we studied the electrokinetic properties of liposomes and SR vesicles as well as the interaction of lipophilic ions with these membranes. The study of electrokinetic properties is based on the measurements of electrophoretic mobility of SR membrane vesicles and PC/PG liposomes. Electrophoretic mobility of SR vesicles was measured as a function of ionic strength for six pH values (pH 4.0, 4.7, 5.0, 6.0, 7.5, and 9.0). Electrophoretic …

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Evaluation Of Voltage Instability Countermeasures In Constrained Sub-Transmission Power Networks, Peter Gibson Jones Jan 2012

Evaluation Of Voltage Instability Countermeasures In Constrained Sub-Transmission Power Networks, Peter Gibson Jones

Dissertations and Theses

This paper investigates the various parameters that effect voltage stability in sub-transmission power networks. The paper first looks at contributions from equipment: generators, transmission lines, transformers, capacitors, SVCs and STATCOMs. The paper also looks at the effects of loads on voltage stability. Power flow solutions, PV and VQ curves are covered. The study models an existing voltage problem i.e., a long, radial, 115 kV sub-transmission network that serves a 65 MW load. The network model is simulated with the following voltage instability countermeasures: adding a capacitor, adding an SVC, adding a STATCOM, tying to a neighboring transmission system, adding generation …

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The Link Between Image Segmentation And Image Recognition, Karan Sharma Jan 2012

The Link Between Image Segmentation And Image Recognition, Karan Sharma

Dissertations and Theses

A long standing debate in computer vision community concerns the link between segmentation and recognition. The question I am trying to answer here is, Does image segmentation as a preprocessing step help image recognition? In spite of a plethora of the literature to the contrary, some authors have suggested that recognition driven by high quality segmentation is the most promising approach in image recognition because the recognition system will see only the relevant features on the object and not see redundant features outside the object (Malisiewicz and Efros 2007; Rabinovich, Vedaldi, and Belongie 2007). This thesis explores the following question: …

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Fostering Hope And Closing The Academic Gap: An Examination Of College Retention For African-American And Latino Students Who Participate In The Louis Stokes Alliance Minority Participation Program (Learning Community) While Enrolled In A Predominately White Institution, Aisha La'chae Hollands Jan 2012

Fostering Hope And Closing The Academic Gap: An Examination Of College Retention For African-American And Latino Students Who Participate In The Louis Stokes Alliance Minority Participation Program (Learning Community) While Enrolled In A Predominately White Institution, Aisha La'chae Hollands

Dissertations and Theses

Colleges are struggling to retain students of color at four-year academic institutions (Kuh, 2005). The result is that while African-American and Latino students are entering college, fewer successfully complete their programs of study and obtain an undergraduate degree (ACE, 2006). For this reason, institutions are establishing supportive learning communities to not only recruit, but to retain this population.Learning communities have become welcoming places in the academy, and are designed to help students succeed in college by providing a formative, integrated academic experience that builds strength, perspective, and commitment. Employing Vincent Tinto`s (1975) student integration theory as a conceptual framework, this …

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Shaping The Future Past: Finding History, Creating Identity In The Kwan Hsu Papers, Lisa Chere' Donnelly Jan 2012

Shaping The Future Past: Finding History, Creating Identity In The Kwan Hsu Papers, Lisa Chere' Donnelly

Dissertations and Theses

Dr. Kwan Hsu was neither a superstar nor a celebrity. Her name does not come up in conversations about important contributors to her field of biophysics nor is she instantly recognizable for her contributions to Portland State University's international program or the state of Oregon's business ties with China. Yet she was a contributor, a cog-in-the-wheel, at the very least, in all of these areas and more. She was a peripheral member of a well-known Chinese family, but few in the United States know of or perhaps have interest in, but otherwise, she had no great connections or family ties …

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Dynamic Ccd Pixel Depletion Edge Model And The Effects On Dark Current Production, Justin Charles Dunlap, Morley M. Blouke, Erik Bodegom, Ralf Widenhorn Jan 2012

Dynamic Ccd Pixel Depletion Edge Model And The Effects On Dark Current Production, Justin Charles Dunlap, Morley M. Blouke, Erik Bodegom, Ralf Widenhorn

Physics Faculty Publications and Presentations

The depletion edge in Charge-Coupled Devices (CCD) pixels is dependent upon the amount of signal charge located within the depletion region. A model is presented that describes the movement of the depletion edge with increasing signal charge. This dynamic depletion edge is shown to have an effect on the amount of dark current produced by some pixels. Modeling the dark current behavior of pixels both with and without impurities over an entire imager demonstrates that this moving depletion edge has a significant effect on a subset of the pixels. Dark current collected by these pixels is shown to behave nonlinearly …

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Proton-Fountain Electric-Field-Assisted Nanolithography (Pen): Fabrication Of Polymer Nanostructures That Respond To Chemical And Electrical Stimuli. An Overview In The Context Of The Top-Down And Bottom-Up Approaches To Nanotechnology, Andres H. La Rosa, Mingdi Yan, Rodolfo Fernandez, Elia Zegarra Jan 2012

Proton-Fountain Electric-Field-Assisted Nanolithography (Pen): Fabrication Of Polymer Nanostructures That Respond To Chemical And Electrical Stimuli. An Overview In The Context Of The Top-Down And Bottom-Up Approaches To Nanotechnology, Andres H. La Rosa, Mingdi Yan, Rodolfo Fernandez, Elia Zegarra

Physics Faculty Publications and Presentations

The development of chemically functionalized materials, such that their physical properties can vary in response to external mechanical, chemical, or optical stimuli, offers potential applications in a wide range of fields, namely microfluidics, electronic memory devices, sensors and actuators. In particular, patterned structures built with stimuli-responsive polymer materials are attractive due to their inherent lower cost production and for building soft scaffolds that mimic closer natural bio-environments. In addition, harnessing the construction of patterns with nanoscale dimensions would not only a) allow building lab-on-a-chip devices that require minimal chemical reactants volumes, but also b) find applications in the area of …

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Ecosystem Health And Ecological Engineering, Robert Costanza Jan 2012

Ecosystem Health And Ecological Engineering, Robert Costanza

Institute for Sustainable Solutions Publications and Presentations

Ecosystem health is a desired endpoint of environmental management and should be a primary design goal for ecological engineering. This paper describes ecosystem health as a comprehensive, multiscale, measure of system vigor, organization and resilience. Ecosystem health is thus closely linked to the idea of sustainability,whichimplies theabilityofthesystemtomaintainits structure(organization)andfunction (vigor) over time in the face of external stress (resilience). To be truly successful, ecological engineering should pursue the broader goal of designing healthy ecosystems, which may be novel assemblages of species that perform desired functions and produce a range of valuable ecosystem services. In this way ecological engineering can achieve its …

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Curriculum Change 2012-2013, Portland State University Jan 2012

Curriculum Change 2012-2013, Portland State University

Bulletin & Curriculum Change Documents

No abstract provided.

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Bulletin: General Catalog Issue 2012-2013, Portland State University Jan 2012

Bulletin: General Catalog Issue 2012-2013, Portland State University

Bulletin & Curriculum Change Documents

No abstract provided.

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Needed: The Solutions Generation, Robert Costanza Jan 2012

Needed: The Solutions Generation, Robert Costanza

Institute for Sustainable Solutions Publications and Presentations

The author argues on the need for a shared vision and focus in solving fundamental problems facing the U.S. He suggests that people should design new political and economic systems that can create shared prosperity without increasing their demands on a finite environment. The author comments that people should vision a refocus on the goal of sustainable human well-being instead of maximizing conventional economic production and consumption.

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On The Skewness Of Order Statistics With Applications, Subhash C. Kochar, Maochao Xu Jan 2012

On The Skewness Of Order Statistics With Applications, Subhash C. Kochar, Maochao Xu

Mathematics and Statistics Faculty Publications and Presentations

Order statistics from heterogenous samples have been extensively studied in the literature. However, most of the work focused on the effect of heterogeneity on the magnitude and dispersion of order statistics. In this paper, we study the skewness of order statistics from heterogeneous samples in the sense of star order. The main results extended the results in Kochar and Xu (2009, 2011). Examples and applications in statistical inference are highlighted.

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Understanding Multidigit Whole Numbers: The Role Of Knowledge Components, Connections, And Context In Understanding Regrouping 3+-Digit Numbers, Eva Thanheiser Jan 2012

Understanding Multidigit Whole Numbers: The Role Of Knowledge Components, Connections, And Context In Understanding Regrouping 3+-Digit Numbers, Eva Thanheiser

Mathematics and Statistics Faculty Publications and Presentations

This case study of a PST's understanding of regrouping with multidigit whole numbers in base-10 and non-base-10 contexts shows that although she seems to have all the knowledge elements necessary to give a conceptually based explanation of regrouping in the context of 3-digit numbers, she is unable to do so. This inability may be due to a lack of connections among various knowledge components (conceptual knowledge) or a lack of connections between knowledge components and context (strategic knowledge). Although she exhibited both conceptual and strategic knowledge of numbers while regrouping 2-digit numbers, her struggles in explaining regrouping 3-digit numbers in …

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Woody Biomass Use Trends, Barriers, And Strategies: Perspectives Of Us Forest Service Managers, Shiloh Sundstrom, Max Nielsen-Pincus, Cassandra Moseley, Sarah Mccaffery Jan 2012

Woody Biomass Use Trends, Barriers, And Strategies: Perspectives Of Us Forest Service Managers, Shiloh Sundstrom, Max Nielsen-Pincus, Cassandra Moseley, Sarah Mccaffery

Environmental Science and Management Faculty Publications and Presentations

The use of woody biomass is being promoted across the United States as a means of increasing energy independence, mitigating climate change, and reducing the cost of hazardous fuels reduction treatments and forest restoration projects. The opportunities and challenges for woody biomass use on the national forest system are unique. In addition to making woody biomass usage pencil out, national forest managers must also navigate substantial public engagement and forest planning processes that add to the complexity of fostering woody biomass use opportunities on the national forest system. We report on the results of a survey of US Forest Service …

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Drinking With Friends: A Cellular Automata Approach To Modeling Peer Influence On Binge Drinking Behavior, Piper Jackson, Andrew Reid, Niki Huitson, Kathryn Wuschke, Vahid Dabbaghian Jan 2012

Drinking With Friends: A Cellular Automata Approach To Modeling Peer Influence On Binge Drinking Behavior, Piper Jackson, Andrew Reid, Niki Huitson, Kathryn Wuschke, Vahid Dabbaghian

Criminology and Criminal Justice Faculty Publications and Presentations

In this project, we adopt Cellular Automata (CA) modeling as a means to focus solely on the elements of concern: individual state (binging) and local interactions (peer pressure). CA models are well suited for exploring the dynamics that occur within a population, and are useful for visualizing the clustering behaviour of communities. With this more abstract approach, it is possible to simulate large populations with reasonable computational requirements.

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"Gift Of The Word" Exhibit Catalogue, Katherine Bass, Karena Bennett, Jeffrey Brown, Bronwyn Dorhofer, Normandie Holmes, Denise Loncar, Alexandra Park, Darcie Hart Riedner, Christy Valentine Jan 2012

"Gift Of The Word" Exhibit Catalogue, Katherine Bass, Karena Bennett, Jeffrey Brown, Bronwyn Dorhofer, Normandie Holmes, Denise Loncar, Alexandra Park, Darcie Hart Riedner, Christy Valentine

Gift of the Word

This is the catalogue for the exhibit "Gift of the Word"

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Building A Sustainable And Desirable Economy-In-Society-In-Nature, Robert Costanza, Gar Alperovitz, Herman E. Daly, Joshua C. Farley, Carol Franco, Tim Jackson, Ida Kubiszewski, Juliet Schor, Peter A. Victor Jan 2012

Building A Sustainable And Desirable Economy-In-Society-In-Nature, Robert Costanza, Gar Alperovitz, Herman E. Daly, Joshua C. Farley, Carol Franco, Tim Jackson, Ida Kubiszewski, Juliet Schor, Peter A. Victor

Institute for Sustainable Solutions Publications and Presentations

This report is a synthesis of ideas about what this new economy-in-society-innature could look like and how we might get there. Most of the ideas presented here are not new. The coauthors of this report have published them in various forms over the last several decades, and many others have expressed similar ideas in venues too numerous to mention. What is new is the timing and the situation. The time has come when we must make a transition. We have no choice. Our present path is clearly unsustainable. As Paul Raskin has said, "Contrary to the conventional wisdom, it is …

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Teaching 21st Century Skills: Voices From The Field, Andrew Kitchenham Jan 2012

Teaching 21st Century Skills: Voices From The Field, Andrew Kitchenham

Northwest Journal of Teacher Education

This article presents an overview of the 21st century student characteristics based on the professional literature. It then outlines specific pedagogical techniques that can be used to improve literacy in school-aged children. It also includes specific examples of these techniques used in North American classrooms.

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What Matters Is Mutual Investment And Evidence-Based Dialogue: Designing Meaningful Contexts For Teacher Learning, Amy E. Ryken, Fred L. Hamel Jan 2012

What Matters Is Mutual Investment And Evidence-Based Dialogue: Designing Meaningful Contexts For Teacher Learning, Amy E. Ryken, Fred L. Hamel

Northwest Journal of Teacher Education

How might teachers be supported as professional learners, in activities and conversations that assist, rather than distract from, the complex work they do each day? In this article we describe a public school/university partnership model designed to support practice-oriented communication among educators– where professionals from various roles, institutional affiliations, and experience levels, communicate together about the details of their teaching. We outline the principles behind our approach and describe the specific practices we use to promote communication that engages teachers’ pedagogical thinking. We share how teachers’ own practice can become a centerpiece of professional development, and how authentic questions and …

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Secondary School Students’ Lack Of Mathematics Understanding, Masomeh Jamshid Nejad Jan 2012

Secondary School Students’ Lack Of Mathematics Understanding, Masomeh Jamshid Nejad

Northwest Journal of Teacher Education

A study was conducted to investigate the influence of pupils’ beliefs on their performance in problem solving. Twenty-seven students from Grade 8 participated in this study. The findings showed that there is a positive correlation between participants’ belief, some subscales of belief and participants’ performance in problem solving. Further research was then suggested. A study was conducted to investigate the influence of pupils’ beliefs on their performance in problem solving. Twenty-seven students from Grade 8 participated in this study. The findings showed that there is a positive correlation between participants’ belief, some subscales of belief and participants’ performance in problem …

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Collaborating To Teach Research Methods In Education, Todd Milford, Catherine Etmanski Jan 2012

Collaborating To Teach Research Methods In Education, Todd Milford, Catherine Etmanski

Northwest Journal of Teacher Education

The purpose of this paper is to describe a pedagogical collaboration between two research methods instructors in a Faculty of Education in Canada. Both instructors represent different paradigms in the classic quantitative vs. qualitative dichotomy in that they were trained in vastly different ways and have tended to approach their research along these same lines. However, despite these differences the paper explores how they each viewed this as a potential limitation in their methods teaching and how through crossing over to each other’s classrooms were able to both expand their own understanding as well as offer a more balanced and …

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Life Changing Events For Students: An Initial Exploratory Study, Michael A. Rousell Jan 2012

Life Changing Events For Students: An Initial Exploratory Study, Michael A. Rousell

Northwest Journal of Teacher Education

The purpose of this exploratory study was to discover under what conditions teachers’ comments create transformative moments for students. This study shows that emotional arousal, frequently triggered by surprise, appears to be a catalyst for the spontaneous and profound restructuring of a student’s personal schema or worldview. Our brains evolved to respond to emotionally intense challenges rapidly and reflexively. These challenges are instantly processed by the brain’s innate, stress-driven, conceptual, problem-solving system. Our reflexive brain system is organized to accept the most expedient solution, not necessarily the best one. It’s thus quite vulnerable to making impetuous responses that may generate …

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An Empirical Test Of Alternative Theories Of Educational Inequality, Arthur Sakamoto, Changhwan Kim, Hyeyoung Woo Jan 2012

An Empirical Test Of Alternative Theories Of Educational Inequality, Arthur Sakamoto, Changhwan Kim, Hyeyoung Woo

Sociology Faculty Publications and Presentations

A classic issue in education centers on the nature of the relationship between schooling and labor market outcomes. Three general theories of this relationship are the human capital view, the market signal view, and the credentialist view. All three approaches predict a positive association between education and wages, but they differ in regard to its underlying causes. We argue that these theories may be fundamentally differentiated in terms of their implications for productivity, and we provide some relevant findings using productivity data for US manufacturing industries from 1976 to 1996. The results most strongly support the market signal view which …

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Freshest Advices On What To Do With The Historical Method In Philosophy When Using It To Study A Little Bit Of Philosophy That Has Been Lost To History, Bennett Gilbert Jan 2012

Freshest Advices On What To Do With The Historical Method In Philosophy When Using It To Study A Little Bit Of Philosophy That Has Been Lost To History, Bennett Gilbert

University Studies Faculty Publications and Presentations

The paper explores the question of the relationship between the practice of original philosophical inquiry and the study of the history of philosophy. It is written from my point of view as someone starting a research project in the history of philosophy that calls this issue into question, in order to review my starting positions. I argue: first, that any philosopher is sufficiently embedded in culture that her practice is necessarily historical; second, that original work is in fact in part a reconstruction by reinterpretation of the past and that therefore it bears some relation to historiographic techniques for the …

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Dynamic Simulation Of Opioid Misuse Outcomes, Alexandra E. Nielsen, Wayne Wakeland Jan 2012

Dynamic Simulation Of Opioid Misuse Outcomes, Alexandra E. Nielsen, Wayne Wakeland

Complex Systems Faculty Publications and Presentations

The objective of the study was to develop a system dynamics model of the medical use of pharmaceutical opioids, and the associated diversion and nonmedical use of these drugs. The model was used to test the impact of simulated interventions in this complex system. The study relied on secondary data obtained from the literature and from other public sources for the period 1995 to 2008. In addition, an expert panel provided recommendations regarding model parameters and model structure. The behaviour of the resulting systems-level model compared favourably with reference behaviour data (R2=.95). After the base model was tested, logic to …

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