{"id":15062,"date":"2022-06-16T20:34:34","date_gmt":"2022-06-17T00:34:34","guid":{"rendered":"https:\/\/carleton.ca\/scs\/?page_id=15062"},"modified":"2026-06-08T15:09:41","modified_gmt":"2026-06-08T19:09:41","slug":"tr-217-indexing-on-spherical-surfaces-using-semi-quadcodes","status":"publish","type":"page","link":"https:\/\/carleton.ca\/scs\/research\/scs-technical-reports\/technical-reports-1992\/tr-217-indexing-on-spherical-surfaces-using-semi-quadcodes\/","title":{"rendered":"TR-217: Indexing on Spherical Surfaces Using Semi-Quadcodes"},"content":{"rendered":"\n<section class=\"w-screen px-6 cu-section cu-section--white ml-offset-center md:px-8 lg:px-14\">\n    <div class=\"space-y-6 cu-max-w-child-5xl  md:space-y-10 cu-prose-first-last\">\n\n            <div class=\"cu-textmedia flex flex-col lg:flex-row mx-auto gap-6 md:gap-10 my-6 md:my-12 first:mt-0 max-w-5xl\">\n        <div class=\"justify-start cu-textmedia-content cu-prose-first-last\" style=\"flex: 0 0 100%;\">\n            <header class=\"font-light prose-xl cu-pageheader md:prose-2xl cu-component-updated cu-prose-first-last\">\n                                    <h1 class=\"cu-prose-first-last font-semibold !mt-2 mb-4 md:mb-6 relative after:absolute after:h-px after:bottom-0 after:bg-cu-red after:left-px text-3xl md:text-4xl lg:text-5xl lg:leading-[3.5rem] pb-5 after:w-10 text-cu-black-700 not-prose\">\n                        TR-217: Indexing on Spherical Surfaces Using Semi-Quadcodes\n                    <\/h1>\n                \n                                \n                            <\/header>\n\n                    <\/div>\n\n            <\/div>\n\n    <\/div>\n<\/section>\n\n\n\n<p>Carleton University<br><a href=\"https:\/\/carleton.ca\/scs\/research\/scs-technical-reports\/technical-reports-1992\/\">Technical Report<\/a>&nbsp;<strong>TR-217<\/strong><br>December 1992<\/p>\n\n\n\n<h2 id=\"indexing-on-spherical-surfaces-using-semi-quadcodes\" class=\"wp-block-heading\">Indexing on Spherical Surfaces Using Semi-Quadcodes<\/h2>\n\n\n\n<p>Ekow J. Otoo &amp; Hongwen Zhu<\/p>\n\n\n\n<h3 id=\"abstract\" class=\"wp-block-heading\">Abstract<\/h3>\n\n\n\n<p>The conventional method of referencing a point on a spherical surface of known radius is by specifying the angular position of&lt;\/&gt; and A with respect to an origin at the centre. This is akin to the ( x, y) coordinates system in R2 cartesian plane. To spec\u00adify a region in the cartesian plane, two points corresponding to the diagonal points (xi, Y1) and (x2, Y2) are sufficient to characterize the region. Given any bounded region, of 2h x 2h an alternate form of referencing a square subregion is by the linear quadtree address [9] or quadcode [12]. Corresponding encoding scheme for spherical surfaces is lacking. Recently a method similar to the quadtree recursive decomposi\u00adtion method has been proposed independently by Dutton and Fekete. Namely, the quaternary triangular mesh (QTM) [4] and the spherical quadtree (SDT) [7]. The addressing method of the triangular regions suggested are very similar. We present a new labeling method for the triangular patches on the sphere that allows for a better and more efficient operation and indexing on spherical surfaces.<\/p>\n\n\n\n<p><a href=\"https:\/\/carleton.ca\/scs\/wp-content\/uploads\/sites\/260\/TR-217.pdf\">TR-217.pdf<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Carleton UniversityTechnical Report&nbsp;TR-217December 1992 Indexing on Spherical Surfaces Using Semi-Quadcodes Ekow J. Otoo &amp; Hongwen Zhu Abstract The conventional method of referencing a point on a spherical surface of known radius is by specifying the angular position of&lt;\/&gt; and A with respect to an origin at the centre. This is akin to the ( x, [&hellip;]<\/p>\n","protected":false},"author":2,"featured_media":0,"parent":11910,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_acf_changed":false,"_cu_dining_location_slug":"","footnotes":"","_links_to":"","_links_to_target":""},"cu_page_type":[],"class_list":["post-15062","page","type-page","status-publish","hentry"],"acf":{"cu_post_thumbnail":""},"_links":{"self":[{"href":"https:\/\/carleton.ca\/scs\/wp-json\/wp\/v2\/pages\/15062","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/carleton.ca\/scs\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/carleton.ca\/scs\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/carleton.ca\/scs\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/carleton.ca\/scs\/wp-json\/wp\/v2\/comments?post=15062"}],"version-history":[{"count":2,"href":"https:\/\/carleton.ca\/scs\/wp-json\/wp\/v2\/pages\/15062\/revisions"}],"predecessor-version":[{"id":24465,"href":"https:\/\/carleton.ca\/scs\/wp-json\/wp\/v2\/pages\/15062\/revisions\/24465"}],"up":[{"embeddable":true,"href":"https:\/\/carleton.ca\/scs\/wp-json\/wp\/v2\/pages\/11910"}],"wp:attachment":[{"href":"https:\/\/carleton.ca\/scs\/wp-json\/wp\/v2\/media?parent=15062"}],"wp:term":[{"taxonomy":"cu_page_type","embeddable":true,"href":"https:\/\/carleton.ca\/scs\/wp-json\/wp\/v2\/cu_page_type?post=15062"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}