Jaan Tollander de Balsch

Jaan Tollander de Balsch

Computer Science & Applied Mathematics

Aalto University

Gamma-Opt

Biography

Jaan Tollander de Balsch is a computer scientist with a background in applied mathematics, who focuses on algorithms, computation, and mathematical modeling. His interests include scientific writing, software engineering, and artificial intelligence. Professionally, he creates practical, well-documented, and tested software packages for solving mathematical and computational problems using Julia language. Apart from work and academics, he is passionate about health, athletics, productivity, and saunas. You can read more about him in the About page or contact him in the Contact page.

Interests

  • Algorithms and Computing
  • Mathematical Modeling and Optimization
  • Julia Language
  • Scientific Writing
  • Software Engineering

Education

  • MSc in Computer Science, 2021

    Aalto University

  • BSc in Applied Mathematics, 2018

    Aalto University

Posts

Searching for Fixed-Radius Near Neighbors with Cell Lists

This article explores the Cell Lists algorithm for performing a fixed-radius near neighbors search through practical implementation in Julia language, analyzes the algorithm theoretically, and benchmarks its performance compared to brute force.
Last updated on 2020-11-03 15 min read Algorithms
Searching for Fixed-Radius Near Neighbors with Cell Lists

Measuring Tail Risk Using Conditional Value at Risk

This article explores the definition and properties of Conditional Value at Risk, a coherent risk measure for measuring tail risk. We also provide an implementation in Julia language for discrete probability distributions.
Last updated on 2020-09-16 9 min read Applied Mathematics
Measuring Tail Risk Using Conditional Value at Risk

Software Engineering Tools, Principles and Practices for Scientists

Read on to learn essential software engineering principles, practices, and tools, and how scientists can write code into collaborative software packages.
2020-05-22 15 min read Software Engineering
Software Engineering Tools, Principles and Practices for Scientists

How to Implement Continuous-Time Multi-Agent Crowd Simulation

This article explores the theory of implementing a continuous-time multi-agent crowd simulation.
2020-01-24 23 min read Simulation
How to Implement Continuous-Time Multi-Agent Crowd Simulation

Computer Algebra With Sympy and Jupyter

This article discusses the benefits and challenges of present-day computer algebra systems and demonstrates computer algebra with Jupyter and Sympy.
2019-11-16 4 min read Applied Mathematics
Computer Algebra With Sympy and Jupyter
See all posts

Books

My books

The Knowledge Worker webbook helps knowledge workers to learn essential tools, skills, and workflows for the digital age. The advice focuses on health, productivity, and ergonomics while keeping information security and privacy in a critical role. Check it out – it is open-source!

Projects

More on GitHub »

Decision Programming

DecisionProgramming.jl is a Julia package for solving multi-stage decision problems under uncertainty, modeled using influence diagrams. Internally, it relies on mathematical optimization. Decision models can be embedded within other optimization models.
Decision Programming

Polytechnic Sauna Society Website

Website for Polytechnic Sauna Society.
Polytechnic Sauna Society Website

Experience

 
 
 
 
 

Research Assistant

Systems Analysis Laboratory, Aalto University

Jun 2020 – Aug 2020 Helsinki Area, Finland
During summer 2020, I worked on creating a Julia package for decision programming, based on research done by Ahti Salo, Fabricio Oliveira, Juho Andelmin, and Olli Herrala. We can use decision programming to solve decision models, representing decision problems under uncertainty, modeled by influence diagrams. We can also embed decision models within other optimization models. The code is available in a repository at DecisionProgramming.jl with the documentation.
 
 
 
 
 

Research Assistant

Systems Analysis Laboratory, Aalto University

Jan 2020 – Mar 2020 Helsinki Area, Finland
During spring 2020, I worked with Fabricio Oliveira and Lucas Condeixa on creating a Julia package for a transmission capacity expansion model, based on their previous research and outside research. The code is available in a repository at EnergySystemModeling.jl with the documentation.
 
 
 
 
 

Research Assistant

Systems Analysis Laboratory, Aalto University

Jun 2019 – Aug 2019 Helsinki Area, Finland
During summer 2019, I worked with Fabricio Oliveira on creating a Julia package for a retail shelf space allocation model, based on his formulation and outside research. The work included programming the mathematical model, and creating visualizations, heuristics, and documentation. The code is available in a repository at ShelfSpaceAllocation.jl with the documentation.
 
 
 
 
 

Research Assistant

Systems Analysis Laboratory, Aalto University

Jun 2017 – Aug 2017 Helsinki Area, Finland
During summer 2017, I continued the work on developing the crowd dynamics simulation. I wrote an extensive blog article about implementing the simulation, which you can find at How to Implement Continuous-Time Multi-Agent Crowd Simulation. The code is available in a repository at crowddynamics.
 
 
 
 
 

Research Assistant

Systems Analysis Laboratory, Aalto University

Jun 2016 – Aug 2016 Helsinki Area, Finland
During summer 2016, I worked on developing and researching a simulation of crowd dynamics with prof. Harri Ehtamo and Anton Von Schantz. Crowd dynamics studies the movement of crowds of humans people, which the simulation aims to recreate computationally. The work included programming with Python using its vast ecosystem of scientific packages and researching and reading research papers about the subject.
 
 
 
 
 

Research Assistant

Department of Mathematics and Systems Analysis, Aalto University

Jun 2015 – Aug 2015 Helsinki Area, Finland
During summer 2015, I researched and wrote my Bachelor’s thesis for the department of mathematics and systems analysis with supervising professor Harri Hakula. My thesis On the Pointwise Convergence of Legendre Polynomials focuses on numerically exploring how a series expansion of step function (sign function) and V-function (absolute value function) using Legendre polynomials converges towards the real value at different points. We then compared the results against theoretical predictions of the convergence rates.

Skills

Strongest skills are in bold. Names are in italics.

Programming

Julialang, Python, C++, C, Haskell, Scala, Bash, Jamstack, Hugo, Markdown, LaTeX

Computer Science

Algorithm design and analysis, Data structures, Scientific computing, Theory of computation, Artificial intelligence

Applied Mathematics

JuMP, Gurobi, Numerical analysis, Computer algebra, Mathematical modeling and optimization

Machine Learning and Statistics

PyTorch, R, Stan, Deep learning, Bayesian statistics

Software Engineering

Git, GitHub, Netlify, Kanban, Testing, Documenting, Continuous Integration

OS & Editors

Linux, Ubuntu, VSCode, JetBrains, Atom

Contact

If you have personal questions for me, you can contact me through email at the address below. Please, state your intention in the title and write your message clearly. Thank you!