PDXScholar: The Institutional Repository of Portland State University

<!DOCTYPE html> <html lang="en"> <head><script type='text/javascript' src='//cdnjs.cloudflare.com/ajax/libs/yui/3.6.0/yui/yui-min.js'></script><script type='text/javascript' src='//ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js'></script><script type='text/javascript' src='https://assets.adobedtm.com/4a848ae9611a/d0e96722185b/launch-d525bb0064d8.min.js'></script><script type='text/javascript' src=/assets/nr_browser_production.js></script>  <meta charset="utf-8"> <meta name="viewport" content="width=device-width"> <title> PDXScholar: The Institutional Repository of Portland State University </title>  <meta name="robots" content="noodp, noydir"> <meta name="description" content="PDXScholar, a service of Portland State University Library, provides access to a diverse collection of academic, scholarly, scientific and creative content produced by faculty, students and staff. PDXScholar increases the visibility of authors' works, maximizes research impact, facilitates interdisciplinary research, and provides regional and global communities with immediate and permanent access.">   <link rel="stylesheet" href="/ir-style.css" type="text/css" media="screen"> <link rel="stylesheet" href="/ir-custom.css" type="text/css" media="screen"> <link rel="stylesheet" href="/ir-local.css" type="text/css" media="screen"> <link rel="stylesheet" href="/ir-print.css" type="text/css" media="print"> <link rel="alternate" type="application/rss+xml" title="Site Feed" href="/recent.rss"> <script type="text/javascript" src="/assets/jsUtilities.js"></script> <script type="text/javascript" src="/assets/footnoteLinks.js"></script>  <link rel="shortcut icon" href="/favicon.ico" type="image/x-icon">  <script type="text/javascript">var pageData = {"page":{"environment":"prod","productName":"bpdg","language":"en","name":"site:index","businessUnit":"els:rp:st"},"visitor":{}};</script> 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href="https://pdxscholar.library.pdx.edu" id="banner_link" title="PDXScholar" > <img id="banner_image" alt="PDXScholar logo with slogan Access for All." width='980' height='100' src="/assets/md5images/28b51ec96488dbdc3a7fa65e6295f612.png"> </a> <a href="https://library.pdx.edu/" id="logo_link" title="Portland State University" > <img id="logo_image" alt="Portland State University Library" width='275' height='100' src="/assets/md5images/2c7abb9d58181a61d4dc2d60646a0610.png"> </a> </div> <div id="navigation"> <div id="tabs" role="navigation" aria-label="Main"><ul><li id="tabone"><a href="https://pdxscholar.library.pdx.edu" title="Home" ><span>Home</span></a></li><li id="tabtwo"><a href="https://pdxscholar.library.pdx.edu/about.html" title="About" ><span>About</span></a></li><li id="tabfour"><a href="https://pdxscholar.library.pdx.edu/cgi/myaccount.cgi?context=" title="My Account" ><span>My Account</span></a></li></ul></div>  </div> <div id="wrapper"> <div id="content"> <div id="main" class="text" role="main">  <div id="dcn-home"> <h1 class="visually-hidden">PDXScholar</h1>  <div id="homepage-intro"> <p id="home-intro">PDXScholar makes the research, scholarship, and creative works of Portland State University faculty, staff, and students easily discoverable and available to anyone, anywhere in the world. <br> <a href="https://pdxscholar.library.pdx.edu/featured.html" >View Our Featured Collections</a></p> </div>  <div id="cover-browse"> <div id="browse-left"> <div class="browse-btn"> <img alt="" width='85' height='48' src="assets/md5images/9a8480e55d548c14063c28be9ac313b2.jpg" alt=""> <a href="https://works.bepress.com/experts/portland-state-university/" title="Faculty Profiles" > Faculty Profiles </a> </div> <div class="browse-btn"> <img alt="" width='85' height='48' src="assets/md5images/4b51fca6dfa933277aeba367a5fb8649.jpg" alt=""> <a href="https://pdxscholar.library.pdx.edu/communities" title="Schools & Colleges" > Schools & Colleges </a> </div> <div class="browse-btn"> <img alt="" width='85' height='48' src="assets/md5images/7919fe9116da850fd03b2b3da7a9d568.jpg" alt=""> <a href="https://pdxscholar.library.pdx.edu/centers" title="Centers & Institutes" > Centers & Institutes </a> </div> <div class="browse-btn"> <img alt="" width='85' height='48' src="assets/md5images/5e242b1257e84045d1b4080bb65390f4.jpg" alt=""> <a href="https://pdxscholar.library.pdx.edu/archives" title="Special Collections & University Archives" > Special Collections & University Archives </a> </div> </div> <div id="browse-right"> <div class="browse-btn"> <img alt="" width='85' height='48' src="assets/md5images/e529206ee3881d56f81bf946a05ab2d0.jpg" alt=""> <a href="https://pdxscholar.library.pdx.edu/etds/" title="Dissertations & Theses" > Dissertations & Theses </a> </div> <div class="browse-btn"> <img alt="" width='85' height='48' src="assets/md5images/ca5f0e9a3c1fa8c0406abe89dc8914d6.jpg" alt=""> <a href="https://pdxscholar.library.pdx.edu/pdxopen" title="PDXOpen Textbooks" > PDXOpen Textbooks </a> </div> <div class="browse-btn"> <img alt="" width='85' height='48' src="assets/md5images/0f75cb5e2f146834614eb6299acfcdfd.jpg" alt=""> <a href="https://pdxscholar.library.pdx.edu/conferences" title="Conferences" > Conferences </a> </div> <div class="browse-btn"> <img alt="" width='85' height='48' src="assets/md5images/e580c902319dbd2620e99df6ec4c873c.jpg" alt=""> <a href="https://pdxscholar.library.pdx.edu/journals" title="Journals" > Journals </a> </div> </div> </div> <div id="readership-map-note"> <h2>Digital Commons Readership Activity Map</h2> <p class="visually-hidden">The PDXScholar Readership Activity Map is a real-time visualization of downloads across the globe. When a reader downloads an item from PDXScholar, a highlighted pin drops on the readership map at the approximate location of the download. The work’s title, author, and collection name appear in an automatic feed, along with location information. <strong>For a keyboard accessible representation of this data, please email <script type="text/javascript"> //<![CDATA[ document.write("<a href='mailto:" + "pdxscholar" + "@" + "pdx.edu" + "'>" + "pdxscholar" + "@" + "pdx.edu" + "<\/a>") //]]> </script> for an Excel spreadsheet of downloads data for a specific collection at a given point in time.</strong></p> <p>Email <script type="text/javascript"> //<![CDATA[ document.write("<a href='mailto:" + "pdxscholar" + "@" + "pdx.edu" + "'>" + "PDXScholar" + "<\/a>") //]]> </script> for an accessible representation of this data</p> </div>  <div id="rdr-embed" data-width="666" data-height="380" scrolling="no" style="margin-top: 20px; overflow: hidden; width: 100%; max-width: 666px;"></div> <script> (function () { var og = window.location.origin; window.rdrAsync = function() { RDR.init({ mapContext: '3790786', datastreamHost: 'datastream.bepress.com', datastreamPort: '443', datastreamStaticRoot: '//assets.bepress.com/20200205/', colorCode: 'custom', customColor: '', customSaturation: 0, customLightness: 0, institution_title: 'Portland State University', site_title: 'PDXScholar', site_link: 'https://pdxscholar.library.pdx.edu', instCountryCode: 'us', instCity: 'Portland', instRegion: 'Oregon', instCountry: 'United States of America', origin: og, embedLink: 'https://pdxscholar.library.pdx.edu/embed_map.html', largeMapLink: 'https://pdxscholar.library.pdx.edu/readership_map.html#content', homepageMap: 1, publicationMap: 0, zoom: 1, minZoom: 1, stats_host: 'https://resources.bepress.com', playbackHost: 'https://playback.bepressaws.com', playbackTimerTID: null, playbackForce: false, }); }; }()); </script> <script src="https://assets.bepress.com/20200205/shared/embed/rdr.js" async="true"></script>  <div class="box aag"><h2>At a Glance</h2><p><a href="https://pdxscholar.library.pdx.edu/topdownloads.html" >Top 10 Downloads<span>All time</span></a> <a class="recent-additions" href="https://pdxscholar.library.pdx.edu/recent_additions.html" >Recent Additions<span>20 most recent additions</span></a><a class="activity-by-year" href="https://pdxscholar.library.pdx.edu/activity.html" ><span>Activity by year</span></a></p></div>   <div class="box potd"><h2>Paper of the Day</h2> <p><a href="https://pdxscholar.library.pdx.edu/oscdl_bonner/96" title="Published in Ernie Bonner Collection" >Northwest comprehensive policies plan map <span>Northwest Comprehensive Policies</span></a></p> </div>  </div>  <div class="clear"></div> <link href="//assets.bepress.com/20200205/shared/floatbox/floatbox.css" rel="stylesheet" type="text/css" media="screen"> <script src="/assets/floatbox/floatbox.js"></script> <div id="network-icon"> <a class="plain fbTooltip" data-fb-tooltip="source:#tooltip1 attachToHost:true" href="https://network.bepress.com" > <img width="16" height="16" alt="DC Network" style="vertical-align:bottom;" src="assets/md5images/8e240588cf8cd3a028768d4294acd7d3.png"> This collection is part of the <span class="dcn-footer-link">Digital Commons Network</span>™ </a> </div> <div id="tooltip1" class="hidden" style="width:auto;"> <div style="float:left;"> <a href="https://network.bepress.com" ><img width="80" height="80" alt="DC Network" style="margin:4px 0 0 4px; border-width:0;" src="assets/md5images/8e240588cf8cd3a028768d4294acd7d3.png"></a> </div> <div style="float:right; font-size:12px; font-family: Arial, Helvetica, sans-serif; margin:8px; width:auto;"> <div id="network"> <p>Visit any of the disciplines in the Digital Commons Network™</p> <p class="links"> <a href="https://network.bepress.com/architecture" title="Architecture" >Architecture</a> • <a href="https://network.bepress.com/arts-and-humanities" title="Arts and Humanities" >Arts and Humanities</a> • <a href="https://network.bepress.com/business" title="Business" >Business</a> • <a href="https://network.bepress.com/education" title="Education" >Education</a> • <a href="https://network.bepress.com/engineering" title="Engineering" >Engineering</a> • <a href="https://network.bepress.com/law" title="Law" >Law</a> • <a href="https://network.bepress.com/life-sciences" title="Life Sciences" >Life Sciences</a> <br> <a href="https://network.bepress.com/medicine-and-health-sciences" title="Medicine and Health Sciences" >Medicine and Health Sciences</a> • <a href="https://network.bepress.com/physical-sciences-and-mathematics" title="Physical Sciences and Mathematics" >Physical Sciences and Mathematics</a> • <a href="https://network.bepress.com/social-and-behavioral-sciences" title="Social and Behavioral Sciences" >Social and Behavioral Sciences</a> </p> </div> </div> </div>  </div> <div class="verticalalign"> </div> <div class="clear"> </div> </div> <div id="sidebar" role="complementary">    <h2>Find</h2> <form method='get' action='https://pdxscholar.library.pdx.edu/do/search/' id="sidebar-search"> <label for="search" accesskey="4"> Enter search terms: </label> <div> <span class="border"> <input type="text" name='q' class="search" id="search"> </span> <input type="submit" value="Search" class="searchbutton" style="font-size:11px;"> </div> <label for="context" class="visually-hidden"> Select context to search: </label> <div> <span class="border"> <select name="fq" id="context"> <option value='virtual_ancestor_link:"https://pdxscholar.library.pdx.edu"'>in this repository</option> <option value='virtual_ancestor_link:"http:/"'>across all repositories</option> </select> </span> </div> </form> <p class="advanced"> <a href="https://pdxscholar.library.pdx.edu/do/search/advanced/?fq=virtual_ancestor_link:%22https://pdxscholar.library.pdx.edu%22" > Advanced Search </a> </p>   <ul id="side-notify"> <li class="notify"> <a href="https://pdxscholar.library.pdx.edu/announcements.html" title="Email or RSS Notifications" > Notify me via email or <acronym title="Really Simple Syndication">RSS</acronym> </a> </li> </ul>    <div id="sb-custom-middle"> <ul class="sb-custom-ul"> <li class="sb-custom-li"> <a href="https://pdxscholar.library.pdx.edu/featured.html" > Featured Collections </a> </li> <li class="sb-custom-li"> <a href="https://pdxscholar.library.pdx.edu/communities.html" > All Works </a> </li> <li class="sb-custom-li"> <a href="https://pdxscholar.library.pdx.edu/authors.html" > All Authors </a> </li> <li class="sb-custom-li"> <a href="https://pdxscholar.library.pdx.edu/communities" > Schools & Colleges </a> </li> <li class="sb-custom-li"> <a href="https://pdxscholar.library.pdx.edu/etds" > Dissertations & Theses </a> </li> <li class="sb-custom-li"> <a href="https://pdxscholar.library.pdx.edu/pdxopen" > PDXOpen Textbooks </a> </li> <li class="sb-custom-li"> <a href="https://pdxscholar.library.pdx.edu/conferences" > Conferences </a> </li> <li class="sb-custom-li"> <a 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PDXScholar: The Institutional Repository of Portland State University