 So, sorry to interrupt you, Marius. All right, so this session is organized by working group one, which is responsible for a theoretical framework for this action. And theory behind quantifying the value of structural health monitoring is mainly by the decision theory. So the aim of presentations at this session is to cover basic aspects of this theory, which are relevant for the action. And the first presentation will be given by Daniel Honfi, who is already here, and the title of his presentation, System Representation. And just a moment. And this will be organized in the following way. So first we'll have all presentations, and then we have hopefully time for questions and discussion. So at the end of the session, after all presentations, I'll invite all speakers back to the stage, and you will be able to ask questions, and we will be also able to have discussion about the topic of this session. Okay, now Daniel. Thank you very much. So I will try to be very quick. And then we could have a lunch at noon. So we were a bit unsure how to present this in a best way, because our hope is that we will have some useful comments here rather than confusing questions, which will then help us to finalize this fact sheet, which is about system representation. It was mainly prepared by myself and Joanne He-Rolzgaard from Rambo. Unfortunately, she cannot be here today. And try to include as much as possible from the actual fact sheet, just to... So then you can even read a text and see what is the content and what we thought that should be included here. It's quite difficult to put something in a fact sheet, relatively short, rather low number of pages. But then the structure was more or less discussed in the working group meeting, and also the template defined a lot of things. So the main parts that we agreed upon and work with Joanne, is that we will talk about utility and risk uncertainty and ranking of decision alternatives, acceptance criteria, and talk about consequences. We thought that we should have an introductionary section and something about system identification, which then turned to be probably the most important one, what we will see. And this is still not the final version, so I hope that we can improve it after this meeting. So the scope of the fact sheet, we thought that it could be given outline about the basic principles of system representation, the context of risk-based decision-making framework, even that could be discussed if risk-based decision-making is the right term. And then highlight is important aspects related to structural monitoring. The abstract proofs, that is something you might want to read. Then we try to explain why is it important to have a special focus on this topic of system representation. Because this is actually turned out to be a crucial part of any kind of risk-based assessment of engineering systems. Then basis theory and methods, then we listed some methods that not necessarily needed to understand this fact sheet, but connected to it, like structuralized with the methods and engineering risk assessment, statistical decision, theory and Bayesian analysis and volume of information theory. The main message here is that the system representation need to be consistent to come to good decisions and there should be no bias due to poor representation of the system. Yes, and these critical comments, critical appraisal. To be able to assess or main goal is to assess the value of or quantify the value of SHM. And these methodologies exist and they could be put into a consistent framework in a relatively straightforward way, but then computational efforts could be become relatively large. So one should always make some simplification, but that should be made by great care. That's a summary or conclusion of this fact sheet. So then some about the main parts of the fact sheet with inspection and monitoring techniques we could of course collect information which could be utilized to reduce risks and uncertainties and therefore risks. But this additional information of course has a price and that should be in balance with the benefits. But in practice that quite often becomes apparent after the installation and operation of the system. But as I said, there exists a framework or there exist methods to handle this and these will be discussed in the other fact sheets of this working group one. So that is described in this introductory part. And then moving to this system representation part, then here reference is made mostly to joint committees work on risk assessment and papers on risk-based decision analysis. One should be able to describe the system in a very generic way represented in this figure. So one should define what constitutes the system and what is the word around it and one should be able to identify the actions that could be taken and decisions and criteria. So there exists a framework for this which is quite clearly described in a general way. And if you see this decision making as playing a game where the aim of the game is to optimize the expected utility then if you want to participate in game then you can do that by buying changes in the system like physical changes to the system or buying knowledge about the system and that is our main focus here with structural house monitoring. This is also explained in our fact sheet. So there is a part on a special focus then on structural house monitoring which in the current state actually is quite long. Maybe it should be shortened. So I hope that some of you might have a possibility to take a look at the actual fact sheet. And here just to mention some important aspects is that in practical situation but also in a theoretical situation it's important to identify the system correctly and then have a rationale of decision making and an acceptance criteria, acceptance of the decisions and then have an idea about perception of risks and consequences with their probabilities and occurrence. So here we included some description about risk-based decision making that it can enable then ranking between decision alternatives in a consistent manner and it enables updating of risks and also that is based on knowledge available at the future and then also one can include responsive actions. So in a structural house monitoring content then these last two are extremely important but that is also described in the fact sheet. Since the time is short and I think I will move to the next section and then we included a description of utility since we stated before the objective of the decision making is to maximize the expected utility which is as you could see this in the previous presentation in practice often clearly focuses on purely economic benefits so costs then here is included perhaps a well-known figure on how the costs and benefits could be represented based on the decision parameters taken from this paper here but also from this GCSS document on existing structures. It's well described. So we try to include the essence of it in this fact sheet and also then one should define risks which is I guess well known for everyone so we just included a basic description of risks in this engineering risk assessment framework. Then there is a relatively significant part to discussing uncertainties first in general which yes is also quite basic thing the different type of uncertainties, allatory uncertainties which is the natural randomness of processes and epistemic uncertainties which are related to the lack of knowledge or lack of data. Then we also try to highlight or describe this in structural house monitoring content that even though this categorization of uncertainties is not really interesting in the way they should be handled in a risk assessment then turned to be quite useful in this context because epistemic uncertainties can be represented with non-physical variables and then the SHM could capture information about this and that could be utilized and also statistical dependencies could be included in this framework. You need to speed up, sorry. Then maybe I could just really focus on the structure so this is then discussed in SHM context how and why uncertainties are important. Then we have a section on ranking in a decision problem this is also quite basic. First and then some issues related to SHM are highlighted. Also included some formulas but didn't want to go to give too much details because that is also perhaps part of the other fact sheets in the working group. Also decision tree is an example. Then we talk about acceptance criteria how it is usually done in standards and then how this optimization should be carried out that was mentioned in this previous slide even including addressing social issues like the value of human life and so on how this could be handled. Also we discussed a little bit the LAP principle when talking about acceptance criteria. Consequences we also have a general discussion about how to represent them in a generic way and talk about direct and indirect consequences and give some examples in the SHM context. Unfortunately I cannot talk too much details about this but you might be able to look at the fact sheets itself and then give us some comments or questions. Okay, thank you Daniel.