A detailed report of findings on the altitudes which can be reached by super pressure balloons and how various factors and considerations affect this. Superpressure balloons are deployed and researched by various organisations including NASA, to solve technical limitations such as cell tower coverage as well as advancing fields of research. Balloons are used in planetary exploration, and weather prediction to teaching primary school physics. The versatile yet simple aerostat has been a valuable tool in many areas of engineering and their altitude ceiling is of great scientific interest. To solve the problem without the ability to physically reproduce the scenario, required mathematical models to be created as a means of simulating the effects of real world physics. A degree great enough to output an accurate and hence useful result without becoming too complex to be computable is the fine balance attempted to be created by this paper.
PDF accessibility requirements stipulate that word breaks must be represented explicitly in the PDF. However, TeX engines do not use space characters to separate words: they use interword glue. This project shows how you can use LuaTeX to replace interword glue with space characters and kerns without affecting the visual appearance of typeset text.
To understand the difference this makes for users of accessibility software, listen to this sound recording made using Adobe Reader DC's Read Out Loud feature. It records the two lines of text in this project being read out loud, before and after converting glue to spaces.
This is a plain TeX file compiled using LuaTeX. It is for experimental use only and not intended to be a full, production-quality solution. Primarily, it is designed to assist with understanding technical issues related to accessible PDFs. The Lua code in this project is based on the earlier Overleaf article Boxes and Glue: A Brief, but Visual, Introduction Using LuaTeX.
This project uses its own simple and very minimal OpenType font loader derived from this code: http://wiki.luatex.org/index.php/Use_a_TrueType_font.