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		<title>IT Playground</title>
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			<title>Git Projects</title>
			<link>https://www.mastersong.de/index.php/it-playground/204-git-projects</link>
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			<description><![CDATA[<p>  

 
<p>Here is an unfiltered list of my Github repositories. Some repos contain real software projects, yet most repos are personal playgrounds or serve demonstration purposes in school.</p> 

 
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			<category>IT Playground</category>
			<pubDate>Mon, 16 Apr 2018 14:06:59 +0000</pubDate>
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			<title>Mathematical Sleep Wake Modelling II</title>
			<link>https://www.mastersong.de/index.php/it-playground/60-research-projects/172-mathematical-sleep-wake-modelling-ii</link>
			<guid isPermaLink="true">https://www.mastersong.de/index.php/it-playground/60-research-projects/172-mathematical-sleep-wake-modelling-ii</guid>
			<description><![CDATA[<p>The two-process model of Daan et. al (1984) was combined with a phase shifting and amplitude altering routine for better entrainment of the circadian processes by light. Genetic algorithms were used to find the appropriate model parameters for the natural distribution of different chronotypes (early birds, owls) that was published by Roenneberg (2007). As a breakthrough, the resulting distribution of one of the 8 free parameters - the circadian period - closely matched both distribution and average of the human circadian period published for experimantal data by Czeisler (1999).</p>
<p>These results were presented at the UKSim 2013 in Cambridge. A<a href="https://www.mastersong.de/images/stories/SSS/UkSim2013/cambridge_08_CH.pdf"> full description</a> as publication and <a href="https://www.mastersong.de/images/stories/SSS/UkSim2013/cambridge_presentation.pdf">presentation</a> are available here.</p>
<center>
<img src="https://www.mastersong.de/images/stories/SSS/UkSim2013/chronotype_distribution_Roenneberg_GA.png" alt="Chronotype Distribution" title="Chronotype Distribution" width="500" />
</br><br>
<img src="https://www.mastersong.de/images/stories/SSS/UkSim2013/tau_distribution_Czeisler_GA.png" alt="Distribution of Circadian Period" title="Distribution of Circadian Period" width="500" />
</center>]]></description>
			<category>Research Projects</category>
			<pubDate>Sun, 21 Apr 2013 06:17:51 +0000</pubDate>
		</item>
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			<title>Lectures on the Art of Scientific Working</title>
			<link>https://www.mastersong.de/index.php/it-playground/60-research-projects/171-lectures-on-the-art-of-scientific-working</link>
			<guid isPermaLink="true">https://www.mastersong.de/index.php/it-playground/60-research-projects/171-lectures-on-the-art-of-scientific-working</guid>
			<description><![CDATA[<p>I am greatful for the oportunity to give a series of lectures on Scientific Working&nbsp; at the University of Applied Science in Schmalkalden.</p>
<p>The following topics were covered in 6 sessions:</p>
<ul>
<li>Choosing and framing the topic</li>
<li>Task and Time planing</li>
<li>Search strategies</li>
<li>Pro and Contra books</li>
<li>Online: Wikipedia, Google Scholar, Scirus</li>
<li>Smart search: Bool operators, distance operators, truncation, wildcards and more</li>
<li>Break down search results</li>
<li>Literature management systems</li>
<li>Literature library of the university (Online-Library, Online-Magazines (Fr. Kritikou)</li>
<li>Reading strategies</li>
<li>Understand and abstract scientific texts</li>
<li>Fast reading techniques</li>
<li>Just write: flow of writing, obstacles</li>
<li>Plagiarism</li>
<li>Correct citing</li>
<li>Creating useful diagrams</li>
<li>Basic Latex introduction</li>
</ul>
<p>Lecture notes are available in German on request.</p>]]></description>
			<category>Research Projects</category>
			<pubDate>Sun, 21 Apr 2013 06:07:23 +0000</pubDate>
		</item>
		<item>
			<title>Lectures on Natural Optimization</title>
			<link>https://www.mastersong.de/index.php/it-playground/60-research-projects/170-lectures-on-natural-optimization</link>
			<guid isPermaLink="true">https://www.mastersong.de/index.php/it-playground/60-research-projects/170-lectures-on-natural-optimization</guid>
			<description><![CDATA[<p>I am thankful for the oportunity to give two lectures on Natural Optimization strategies at the University of Applied Science in Schmalkalden. The different ways of natural optimization provide powerful and fascinating&nbsp; opportunities to tackle mathematical problems beyond classic computational borders.</p>
<p>Topics were:</p>
<ol>
<li>Basics of Optimization</li>
<li>Evolutionary Algorithms</li>
<li>Ant Colony Optimization</li>
<li>Particle Swarm Optimization</li>
</ol>
<p><a title="Powerpoint Presentation (german)" href="https://www.mastersong.de/images/stories/SSS/NatOpti/NatOpti_II.pdf">Lecture notes are available here (german).</a></p>]]></description>
			<category>Research Projects</category>
			<pubDate>Sun, 21 Apr 2013 05:20:59 +0000</pubDate>
		</item>
		<item>
			<title>Mathematical Sleep-Wake Modelling</title>
			<link>https://www.mastersong.de/index.php/it-playground/60-research-projects/108-mathematical-sleep-wake-modelling</link>
			<guid isPermaLink="true">https://www.mastersong.de/index.php/it-playground/60-research-projects/108-mathematical-sleep-wake-modelling</guid>
			<description><![CDATA[<p>An ongoing project that has already been the core of my Diploma thesis:</p>
<p>In Collaboration with the Neuroinformatic Research Group at the University of Applied Science in Schmalkalden, a mathematical model for human Sleep-Wake-Rhythm prediction is proposed, that accounts for both Sleep homoeostatis and adaption of the circadian day to daylight.</p>
<p style="text-align: center;"><img class="Caption" src="https://www.mastersong.de/images/stories/SSS/kombi_modell.PNG" alt="Combined Model for Human Sleep-Wake Rhythm" title="Combined Model for Human Sleep-Wake Rhythm" style="vertical-align: middle;" border="0" height="203" width="600" /></p>
<p>The model shown above is a combination of the 2 Process Model [Daan,Beersma,Borbely] and the Phase Response Curve [DeCoursey, Pittendrigh]. The 2 Process Model (<em>2PM</em>) consists of the upper and lower sinodial circadian thresholds for sleep onset (green) and waketime (blue), further called <em>Process C</em>. In between, the sleep pressure (<em>S</em>) raises during waketime and falls during sleep. If one of the thresholds of Process C is met, S changes from Sleep to Wake state or vice versa.</p>
<p>The Phase Response Curve (<em>PRC</em>, thin blue line) is a mathematical model that accounts for the adaptation of the inner circadian clock to the solar day. Based on various experiments it was verified, that bright light in the subjective morning would accelerate the circadian clock, and bright light in the subjective evening slows it. Habitual sleeptime at night prevents the circadian clock to be altered too much. In the proposed combined model, both Process C and PRC run at the same circadian period (23.5 to 25hrs). If light hits an active part of the PRC, the phase shift is applied instantly to Process C and accumulated to later shifting on PRC. Further, the total sum of absolute product of light and PRC value during the day is calculated for attenuation of both PRC and Process C.&nbsp;</p>
<p>Humans happen the have different Sleep-Wake behaviours (further called <em>Chronotypes</em>), ranging from "Larks" awaking before sunrise after only 4.5hrs of sleep to "Owls" awaking just before noon after perhaps 12hrs of sleep. Various model parameters must be fitted to account for people with different chronotypes, which was achieved using Genetic Algorithms. The illustration below shows the fitting of a simulated Sleep-Wake-Cycle with fitted model parameters to the Sleep-Wake-Cycle recorded in a sleep diary over almost 150 days.</p>
<p style="text-align: center;"><img class="Caption" src="https://www.mastersong.de/images/stories/SSS/GA_CT_sim_sw_data.png" alt="GA CT sim sw data" title="Simulated and Real Sleep-Wake data after Parameter Optimization" /></p>]]></description>
			<category>Research Projects</category>
			<pubDate>Fri, 10 Sep 2010 04:10:43 +0000</pubDate>
		</item>
		<item>
			<title>Schedule Evaluation for Chronotype Performance</title>
			<link>https://www.mastersong.de/index.php/it-playground/60-research-projects/107-schedule-evaluation-for-chronotype-performance</link>
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			<description><![CDATA[<p>Based on our Sleep-Wake Model, shift schedules can be simulated for different chronotypes and examined for their suitability regarding sleep deprivation, forced waking and accumulated sleep lacks. Goal is to find schedules with reduced impact on these factors, hence provide better vigilance during work hours.</p>
<p><img style="vertical-align: middle;" mce_style="vertical-align: middle;" title="Schedule Simulation Software" alt="Schedule GUI IV" src="https://www.mastersong.de/images/stories/SSS/Schedule_GUI_IV.jpg" mce_src="https://www.mastersong.de/images/stories/SSS/Schedule_GUI_IV" height="333" width="600" /></p>]]></description>
			<category>Research Projects</category>
			<pubDate>Fri, 10 Sep 2010 04:04:30 +0000</pubDate>
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