Converting Journal Article from LaTeX to Markdown

, 11 min read

1. Problem statement. You have a scientific journal article in LaTeX format on arXiv but want it in Markdown format for a personal blog. In our case we take the article "A Parsec-Scale Galactic 3D Dust Map out to 1.25 kpc from the Sun" from Gordian Edenhofer et al. The original paper is…

Performance Comparison of Ristorante Panorama Website: WordPress vs. Simplified Saaze

, 2 min read

In the previous post Example Theme for Simplified Saaze: Panorama I demonstrated the transition from a website using WordPress to Simplified Saaze. This very blog also uses Simplified Saaze. This post shows how much better performance-wise this transitions was. The comparison is therefore…

Example Theme for Simplified Saaze: Panorama

, 8 min read

1. Features. Here is another theme called Panorama for Simplified Saaze. The example content is from Ristorante Panorama. This theme has below properties: It is geared towards restaurants with menus Responsive with media-breaks for 1-column, 2-column, 3-column, and printer output RSS and…

Malcolm Gladwell: Meritocracies don't work

, 16 min read

Malcolm Gladwell was invited to Google Zeitgeist again. He gave a talk on meritocracies and their failures. This is somewhat a follow-up on his earlier talk given on Google Zeitgeist. I had written on this prior talk here: Malcolm Gladwell: Don't go to Harvard, go to the Lousy Schools!. The talk is…

Performance Comparison gzip vs Brotli

, 2 min read

The NGINX web-server offers gzip, deflate, and Brotli compression. My current nginx.conf file uses brotli_comp_level 10; It looks that indeed the default Brotli compression level 6 is a sweet spot for Brotli. 1. Measurement. I used below software versions: Arch Linux kernel 6.4.12-arch1-1 Brotli…

From Hiawatha to NGINX

, 8 min read

1. Motivation 2. NGINX installation 3. Brotli compilation for Arch Linux 4. NGINX configuration 5. Caching 6. Deployment Since mid of August I switched from Hiawatha web-server to NGINX web-server. I initially intended to use OpenLiteSpeed web-server. See Installing OpenLiteSpeed on Arch Linux,…

Crucial 4TB SSD in Asrock A300M

, 3 min read

Task at hand: Increase SSD storage on Asrock A300M mini-PC, as existing SSD is 90% full. Solution: Buy a new 2 TB SSD, or use an existing 2 TB SSD, for example a Samsung. Bad idea: Buy a new 4 TB SSD from Crucial and insert it into the A300M. 1. Problem statement. Since May 2020 I own an Asrock…

Mixing PHP into Markdown

, 3 min read

Markdown is a simple language to write documents, which are finally converted to HTML. There are many conversion programs to convert from Markdown to HTML. This blog uses MD4C for this. The CommonMark specification says: An HTML block is a group of lines that is treated as raw HTML (and will not…

Installing OpenLiteSpeed on Arch Linux

, 3 min read

Unfortunately the AUR package for installing OpenLiteSpeed is broken. Additionally, the manual installation of OpenLiteSpeed via self-compilation is a mess. 1. Downloading rpm. Here we describe using the rpm repository of /edge/centos/8/x86_64/RPMS/. Essentially, this is a precompiled binary in…

Blog Anniversary: 500 posts

, 1 min read

This blog now has more than 500 posts. 1. Data. Generating static HTML files with Simplified Saaze shows number of posts: $ time php saaze -mortb /tmp/build Building static site in /tmp/build... execute(): filePath=/home/klm/php/sndsaaze/content/aux.yml, nentries=6, totalPages=1,…

cpio command cheat sheet

, 1 min read

cpio is a command, which is less used than tar. So the required options are often forgotten. cpio needs the < redirection to get its archive from stdin. List content of cpio-archive: cpio -tv < archive Extract data out of cpio-archive: cpio -idmv < archive, -i is extract, -d creates…

A Parsec-Scale Galactic 3D Dust Map out to 1.25 kpc from the Sun

, 82 min read

Author Gordian Edenhofer (1,2,3) Catherine Zucker (3,4) Philipp Frank (1) Andrew K. Saydjari (3) Joshua S. Speagle (5,6,7,8) Douglas Finkbeiner (3) Torsten Enßlin (1,2) } Institute Max Planck Institute for Astrophysics, Karl-Schwarzschild-Straße 1, 85748 Garching bei München, Germany Ludwig…

Profiling PHP Programs #2

, 44 min read

After adding a number of smaller features to Simplified Saaze I wanted to make sure that not too much fat has been added. So I profiled Simplified Saaze with XHProf. I had written on PHP profiling in Profiling PHP Programs. I used XHProf version 2.3.9 and PHP version 8.2.8 on Arch Linux kernel…

Hosting Static Content with Neocities

, 3 min read

I wrote about hosting static sites on various platforms: Hosting Static Content with surge.sh Hosting Static Content with now.sh, now.sh renamed themself to vercel.app Hosting Static Content with netlify.app Hosting Static Content with Cloudflare This short post documents how to upload static…

Steve Jobs on Bicycles

, 3 min read

1. Energy efficiency. Steve Jobs was impressed by the efficiency of the human riding a bike. Steve Jobs has cited this comparison multiple times during his life. Probably he was referring to this chart in Scientific American: Bicycles are very efficient, see The science of bicycles by Chris…

Data Centers in Africa

, 1 min read

1. Wikipedia. Wikipedia has a total of five data centers in the US, Europe, and Singapore. They are given in below table as of 2023. Nr. Location Role Since 1 Virginia, USA Application + Caching 2010 2 Texas, USA Application + Caching 2014 3 Amsterdam,…

Performance Remarks on PublicoMag Website

, 2 min read

Publico is a German political magazine published by Alexander Wendt. The website is using WordPress and hosted on Cloudflare. Webserver is NGINX. It contains content since Oct-2017. 1. Frankfurt. Below is an analysis conducted via pingdom.com. Page in question is Inspiration als Energiequelle:…

Example Theme for Simplified Saaze: Paternoster

, 7 min read

1. Features. Here is another theme called Paternoster for Simplified Saaze. The example content is from Leon Paternoster. Some key features: Multiblog: 3 different blog types, i.e., one classical blog, one Twitter like blog, one link-collection blog Lightweight as there are no gimmicks, no social…

Neural Network Training using Stiff ODE Solvers

, 4 min read

This post recaps the paper from Aaron J. Owens and D.L. Filkin from 1989: Efficient Training of the Back Propagation Network by Solving a System of Stiff Ordinary Differential Equations. 1. Neural network. Below is a single "neuron": Input to node $Q$ is given in $A_i\in\mathbb{R}$,…

Theorem of Stein and Rosenberg

, 5 min read

This post recaps content from Homer Walker in his handout, and Richard Varga's classic book "Matrix Iterative Analysis". Below tables show the three standard iterations for solving the linear system $Ax=b$, with $A=(a_{ij})\in\mathbb{R}^{n\times n}$, and $x,b\in\mathbb{R}^n$; index $i$ is…