Dutch researcher Laura Brandán Briones, that's who.
She improved both the tests and the method to determine the reliability of the tests. This means, for example, that washing machines and coffee machines can be tested far better before they are launched on the market.
Brandán Briones made several considerable improvements. First of all she made it possible to include the factor 'time' in the testing. Not only can it be determined if coffee actually comes out of the machine but also how long that takes.
Brandán Briones developed a good measure for establishing the reliability of the tests. This can be achieved by determining which part of the system has been tested: the degree of coverage. An equally large problem during the testing of software is the gigantic number of scenarios that a system offers. This is more than the number of elementary particles in the universe. It is therefore impossible to test all of these. The degree of coverage is a measure of the reliability of the system. If you have a coffee machine with tea and coffee and you test all of the possible options that supply coffee then you have a degree of coverage of 50%.
The old method for determining this degree of coverage assumed all possible processes in a system to make, for example, a cup of black coffee. However the system can deliver the same cup of coffee in various ways. Using the method of Brandán Briones all of the different ways are assigned the same value. Therefore the degree of coverage no longer varies.
The method Brandán Briones has developed is the first that also takes into account the severity of possible errors. This is a major advantage for companies that want to make a risk estimate. Taking into account the importance of the errors provides a far more accurate and realistic measure of reliability. It is far worse if you get milk in black coffee than that the strength is not exactly right.
Computer chip manufacturer ASML has followed the work of Brandán Briones with interest and is currently making use of it. The research of Brandán Briones was part of the NWO project Systematic Testing of Realtime Embedded Software Systems (STRESS).