Olivier Nusbaumer: Resources

I have released a few of my research projects to the public domain:

NeuralSpectrum

Since you have landed here, you are most likely looking for the Binary Decision Diagram (BDD) software I have developed.
This software is an integrated fault tree / BDD tool that features a fault tree package, a BDD engine and a minimal cutset engine, with dedicated fault tree to BDD conversion and optimization routines. The optimization routines include global, static (pre-processing), dynamic and local (BDD objects) techniques.

Using this tool and techniques, I succeeded in converting a fullscope linked fault tree model, as found in nuclear power plants, to its BDD form. This was a major achievement, because the BDD represents a canonical solution of the model: we were able, for the first time, to solve such models correctly and completely. I was also the first one to be able to generate a BDD video of a realistic model, which helped to better understand how such complex mathematical structures look like in practice.

This tool was developed in C# 2005 and is freely available here. However, before you can use it, you have to agree, sign and return this agreement form to me.

PhD-Thesis

You can find my PhD thesis here (without the appendices and the source code): "Analytical Solutions of Linked Fault Tree Probabilistic Risk Assessments using Binary Decision Diagrams with Emphasis on Nuclear Safety Applications" (Diss. ETH No. 17286, 2007).

Ontronic

I am the designer of the Ontronic product line, and the sale manager.

Ontronic is a programmable Engine Management System (EMS) for racing applications, that allows the user full control over fuel and ignition timing to gain maximum performance from their motor vehicle. It can be implemented on any engines from 1 to 12 cylinders, naturally aspirated or supercharged, phased (fully sequential up to 8 cylinders) or not phased (e.g. 2 stroke). It features real-time tuning capabilities and provides logging of engine data.

The software was developed in Borland C++ 6 and can be found here. However, before you can use it, you have to agree, sign and return this agreement form to me. The PCB and the firmware are not publicly available though (copyright).

Seismic Hazard Quantification

I have published several papers on Probabilistic Seismic Risk Assessment (PSRA), the best known of which addressed the quantification issues; it can be found here: "Analytic Solution of Seismic Probabilistic Risk Assessment" (In Proc. ESREL, 2005). It was the first publication to investigate the impact of the rare event approximation on seismic PRA. It also introduced new ways to quantify fragility distributions semi-analytically.

The fragility computer code can be found here.

Bayesian Update Tool

I have developed a Bayesian update computer code, as part of a bigger project to automatically process nuclear power plant reliability data. It was published in RiskSpectrum Magazine Issue 1, 2004.

The Bayesian update computer code can be found here.

Human Reliability Analysis Tool (HRA-Tool)

I have developed several HRA tools, used at various nuclear power plants, including an automatic pre-initiator Human Error Probability (HEP) quantification engine based on the THERP / ASEP methodologies. It has been (very) succinctly described here (German translation available here). This tool does not only calculate the HEP values, but also produces the corresponding quantification documentation for the reviewer (example).

The computer code can be found here.

Decay Heat Calculation Software

I have developed a C++ software to calculate the decay heat level of nuclear reactors after shutdown, based on the ANS-5.1-94 standard. This software, called DECANS V1.2, is useful to define core configuration. In addition, it is suitable for PRA Level 2 applications, analysis and real-time accident simulation. DECANS V1.2 automatically evaluates the fractional fission contribution of each fissile isotope (²³⁵U, ²³⁸U, ²³⁹Pu and ²⁴¹Pu) based on the fuel burnup using published fractional contributions for Light Water Reactors (LWRs).

The core of the computer code can be found here. It includes the official ANS tables, that can be used for other applications. More details can be found on the DECANS website.

Olivier Nusbaumer, 2008

W3C validated