pages tagged library_science http://meng6net.localhost/tag/library_science/ <p><small>Copyright © 2005-2020 by <code>Meng Lu &lt;lumeng3@gmail.com&gt;</code></small></p> Meng Lu's home page ikiwiki Fri, 08 May 2020 20:51:23 +0000 中国古代书籍分类 http://meng6net.localhost/journal/%E4%B8%AD%E5%9B%BD%E5%8F%A4%E4%BB%A3%E4%B9%A6%E7%B1%8D%E5%88%86%E7%B1%BB/ http://meng6net.localhost/journal/%E4%B8%AD%E5%9B%BD%E5%8F%A4%E4%BB%A3%E4%B9%A6%E7%B1%8D%E5%88%86%E7%B1%BB/ TODO academics business information taxonomy journal library library science reference scholar sysadmin Fri, 08 May 2020 20:51:23 +0000 2020-05-08T20:51:23Z <h2>中国古代书籍分类</h2> <ul> <li> <p>中国古代书籍可以定义为1912年之前出版印行及1912年之后影印等形式的同类电子图书。</p> </li> <li> <p>经部</p> <ul> <li>易、书、诗、三礼礼制、乐、春秋、四书、孝经、小学、群经总义、谶纬、丛编、石经等</li> </ul> </li> <li>史部 <ul> <li>正史別史、编年、纪事本末、杂史、载记地理、史表、史评史抄、传记、政书职官、诏令奏议、金石、目录、丛编等</li> </ul> </li> <li>子部 <ul> <li>儒家、道家、兵家、法家、农家、医家、杂家、小说家、天文历算、术数、艺术工艺、丛编等</li> </ul> </li> <li>集部 <ul> <li>楚辞、别集、总集、诗文评、词 、曲、小说、丛编等</li> </ul> </li> <li>丛部 <ul> <li>类书通类、类书专类、杂纂丛书、辑佚丛书、郡邑丛书、氏族丛书、独撰丛书、丛书补缺等</li> </ul> </li> </ul> <h3>TODO</h3> <ul> <li>补充各类书籍实例。</li> </ul> Graphlet: a readable serialized representation of graphs http://meng6net.localhost/blog/graphlet/ http://meng6net.localhost/blog/graphlet/ graph idea library science metadata notation Tue, 16 May 2017 23:59:39 +0000 2017-05-16T23:59:39Z <p>A tree graph is uniquely identified by the set of its edges</p> <pre> <code>{1-&gt;2, 1-&gt;3, 2-&gt;4, 2-&gt;5, 2-&gt;6, 3-&gt;7, 3-&gt;8} </code></pre> <p>This syntax is used in <a href= "http://reference.wolfram.com/language/ref/Graph.html">Wolfram Language's graph specification</a>. The actual picture of the graph can be displayed in Mathematica with:</p> <pre> <code>Graph[{1 -&gt; 2, 1 -&gt; 3, 2 -&gt; 4, 2 -&gt; 5, 2 -&gt; 6, 3 -&gt; 7, 3 -&gt; 8}] </code></pre> <p>It can be <a href= "https://www.wolframalpha.com/input/?t=crmtb01&amp;f=ob&amp;i=graph%201%20-%3E%202%2C%201%20-%3E%203%2C%202%20-%3E%204%2C%202%20-%3E%205%2C%202%20-%3E%206%2C%203%20-%3E%207%2C%203%20-%3E%208"> drawn in Wolfram|Alpha conveniently with query "graph 1 -&gt; 2, 1 -&gt; 3, 2 -&gt; 4, 2 -&gt; 5, 2 -&gt; 6, 3 -&gt; 7, 3 -&gt; 8"</a>.</p> <p>The question is: is there a better way to represent the graph in a compact, readable, and text-only form?</p> <h2>Why?</h2> <p>A few use cases which might give some motivation:</p> <ol> <li> <p>In tweets, sometimes, one might want to include graphs accurately represented by a short sequence of regular characters, which ideally should also be easy to parse as-is (instead of only after being processed by software such as Mathematica's <code>Graph[...]</code> function.)</p> </li> <li> <p>When labeling/classifying objects, besides using tags which are a flat list of IDs of form <code>{tag1, tag2, ...}</code> and equivalent to a graph with vertexes but no edges, one can use a tree graph represented in a succinct form to carry more information about the hierarchical classification of the object.</p> </li> </ol> <h2>One way: list of tags</h2> <p>One obvious way is to write the list of edges such as <code>{1-&gt;2, 1-&gt;3,2-&gt;4, 2-&gt;5, 2-&gt;6, 3-&gt;7, 3-&gt;8}</code>, which uniquely identifies the graph. It's not very compact -- vertexes with multiple children is repeated -- and neither very readable -- one need to do much mental processing and memorizing in order to understand and imagine the structure of the graph.</p> <h2>Another way: "graphlet"</h2> <p>Another way I designed is to write it into the following form, which I dubbed "graphlet representation" of (tree) graphs:</p> <pre><code>1`{2`{4, 5, 6}, 3`{7, 8}} </code></pre> <p>So, in graphlet representation:</p> <ol> <li> <p>The edges in a graph are represented by an edge character (backtick for instance);</p> </li> <li> <p>Child vertexes are grouped by a pair of grouping characters (<code>{</code> and <code>}</code> for instance).</p> </li> </ol> <p>Note that the graphlet representation is shorter than the flat list-of-edges representation.</p> <h2>Classification graphlet is more informative than list of tags</h2> <p>An object's classification is often represented as a list of tags</p> <pre><code>{tag1, tag2, ..., tag8} </code></pre> <p>However, if the classification is hierarchical, a graphlet representation can easily records more information about the classification structure:</p> <pre><code>tag1`{tag2`{tag4, tag5, tag6}, tag3`{tag7, tag8}} </code></pre> <h3>Application examples</h3> <p>To represent the classification of a problem, a sequence of key words is often used, e.g.</p> <pre> <code>astrophysics, cosmology, general-relativity, star, galaxy </code></pre> <p>One can actually additionally include its hierarchical classification structure by using a graphlet:</p> <pre> <code>science`{physics`{astrophysics, cosmology, general-relativity}, astronomy`{star, galaxy}} </code></pre> <h3>Advantages</h3> <p>Preserving the full graph structure, many graph characteristics can be exploited, and graph-theoretic methods can be used for analyzing metadata in this form. For example, graphlets can be systematically shorten/simplified by pruning leaves.</p> /blog/graphlet/#comments