 Dat is wel een klein beetje, maar er is een focus op de alternaties voor de gevoelst in de Roosland-centrums. De gevoelst is meedwaardig aan me, maar ook aan mijn collega's, die in mijn en die centrum-centrum-centrum-centrum-centrum-centrum. In general, ik ga volgen van de list van content die is propost. Maar ik zal een kort introductie om een paar research-programma's te laten zien wat we nu vormen, we zijn hier nu, die ook in de context van onze gebruik is. Over de vorige jaren doen we een research-programma, om te kijken naar de complete structures in de levelis. We hebben er al opgemaakt om de hoogte op te doen, dat was bijvoorbeeld in de bg's-lectio. En in de bg's-lectio hebben we er al opgemaakt om verschillende sources van ontwikkeling. Zoals we in de materiaal-properaties hebben gezien. En we hebben ook de aantreving voor de ontwikkeling gezien, als we naar de, wat zeggen, de vaste, non-linear, quantitative modelling van de structuren. One particular thing is then also that we do research with respect to corrosion. The assessment and prediction lay out of our research program is relatively standard in terms that we have structural health monitoring or information that we get that we use for the condition assessment by modelling these modelling that can take place on different levels, but they are used to update our self-slide predictions for this, I guess one of these schemes that go around over the world with respect to that. Also part of this research program is the development of a new layout of type of corrosion centre. The idea behind that is that what would it mean if not only one physical quantity is being measured as a corrosion indicator, but we try to simultaneously measure not all physical quantity. So in this case we are measuring resistances on surface with respect to the color but also color density and corrosion potentials, as well as also extra data and additional data from intake testing and sampling, for instance water cement ratio or cement drops. We then use statistical models to capture the relations and then come not only with the sensor use, but also with an autonomous interpretation model. So this is what we need to do. We have data, physics and expert agreements and all this knowledge is then captured in a Bayesian network which then behaves as an interpretation model for the sensor period and gives as a result the likelihood of corrosion based on all the indicators. Here below we see a simple configuration of the Bayesian network for the interpretation. In blue there are the intake parameters, water cement ratio, cement type en in green there are all the sensor values. All these data are then combined in a kind of artificial intelligence model towards the predictor, whether or not there is an effective corrosion in fact, the outcome of this model gives you the probability of corrosion being affected. Then the next point decision scenario. We want now to use the value of information concept also to decide which structural health point or intake should the owner apply in a way that it deserves to the minimization of the remaining service life costs. And of course there are a lot of things where this depends upon the cost, the occurrences of the measurement techniques possible actions as information has to lead to actual status structure and of course the cost of benefits related to the period. The decision scenario. I presented this field chart. Decision maker would be the public authority of all the municipality. We are looking at an objective function that minimizes the life cycle cost. Performance is evaluated respectively for the serviceability. We will look at the correct sizes occurring as a result of the corrosion indicators. Some of them I have already mentioned. We have corrosion capacity, cobalt assistance, surface assistance and cobalt potential. A library of possible actions to be taken. Coding, cobalt renewal, or maybe cathodic protection. Objectives I have already mentioned, the compensation of the cost but it is all in the context of maintenance actions. We want to apply the data information concept also using two alternatives for sensory. The first one is the let's call it a more traditional corrosion potential measurements also potential measurements. And the other one, the alternative is the aforementioned multi-sensor. But the case study might be general, as David has suggested In fact we took a few tissues, but we enforced concrete establish located in the bottom end. We focused on the crack risk and the metal support the two sectional corrosion links. For now, as it is still in the bottom end of development we look at two possible actions meaning no action or cathodic protection. En below on this sheet there are some figures that describe the properties and dimensions of their case. For now, I'm still making quite large assumptions as we can read here. We state now that those measurements are deeply expensive en we also state now that the multi-sensor node will have a better information compared to the half self potential measurements. An indication of this better information is given in these probability tables where the likelihood of probability is given that a type of sensor gives a positive indication of deep observation given that there's actually also deep observation present. The metal supplied is again a Bayesian network and Jorgen this morning explained some teachers of the Bayesian network already. Basically all these yellowish nodes they stand for stochastic parameters, physical parameters then we have these squares which are decision nodes so alternatives can be chosen and the effect of those choices can be calculated and then we have the green diamonds which stands for utility nodes where costs can be accounted for. So this decision node for instance decides whether or not there is structural monitoring to be applied and also what kind of structure else monitoring is applied. So the traditional potential measurement for the multi-sensor node each of them have a process. Net observations with this measurement monitoring to are obtained based on five models which then have to be translated towards load effect on effect in this case a correctness. These correctness are then associated with costs and also these derived quantities are then related to actions of speed also in this speed then monitoring obtaining information will lead to amount of actions or assist to be made about actions. So the models involved in this study are still under development and what we will do is add five models for their depreciation we have to take into account recent developments of our multi-sensor node the costs as I stated they are taking people to each other now they have time to be quantified appropriately the time as parameter to be included other actions like encoding or renewal of the code we also have to have a closer look at the spatial variability whether it is associated with that those not to be obtained as it is to the development were best being at the end the value of information has to be calculated so that there will be an outcome in terms of odd variables on one but also the decision rules will be obtained so the type of sensor will be chosen for but also the postponing maintenance policy will be desired we had a very large structural estimate of information for the owner on session there for the owner obtain a minimised total maintenance of course we will also then provide the optimal structural estimate and method the options that were investigated accompanied by the optimal maintenance policy for the next years and for this maintenance policy it has to be said that this policy can also be adaptive or dynamic so the recent network that I showed before is being used for the value of information study what once it is there and a certain monitoring device is active it can later on still be used to update the maintenance policies for coming years once information is also actually obtained from the monitoring system these are results for the owner but I think also respect to the sensor there is some information obtained you get an insight in the value of information of the sensor this can be used as a kind of business case for the sensor and it could be or will be development incentives for innovation and developments for the sensor very much indeed we have this can be general concrete bridges do you have do we have first questions from the audience what is your impression of health monitoring for concrete bridges for a class of bridges let's say concrete bridges which is the classical structures we monitor my general question is also for the audience are there any or do you apply for a class of concrete bridges let's say you have many concrete bridges and you select based on some principle five to do the structural health monitoring so out of the class of structures which one you monitor are you applying this or are you applying this in Portugal so you have a class of structures and you say we have to take the most critical ones and see what we can conclude for the others I believe that we are doing that this is my first question where you are in that part I don't have a stable framework for that everybody is searching to classify the bridges in order to they are in order to sensitivity, risk and priority and the inspection program would depend on the criticality of the bridge so you would appreciate if guidelines would focus on this so this is a very interesting thing to see type of structures are there some questions here before we take the break we have five minutes any questions discussion yes maybe a discussion point is you are mentioning that you prioritize program based on criticality but in terms of monitoring what is that criticality is that they have the highest or the highest failure probability or is it that they have the highest uncertainty in terms of strength so maybe that's a thing to be discussed because it's a correct or incorrect feeling about in this case what I presented here was that you service would be a good thing really in the context of failure of the story with this and in that for that reason I also think that in the Netherlands not much of many pictures are being monitored basically they are regularly monitored we do think there are there's a vast number of pictures arriving towards a state where corrosion will be the research that we are doing now is to be prepared to respond to also a kind of priority this can be settled in those actions in the future we we we we we we we we we we we we we we we we we we we we we we we we we we we we we op het risico van gevolg en de risico van de verdediging. Dus als je in je presentatie maakt om zes sensors en zes dikes te doen, betekend op de eerste inspectie, en ook dat je op het eerst klinkt of dat het gevoel is of niet. Dat betekent dat de dike ervoor moet worden, de vervolking, de studies. En dan denk ik dat het framework is dezelfde. Dat de eerste die de bridge's en de slops, en de waarde structuur klinkt, op de technologie, weten we al dat pre-cast bridges meer vervolkingen zijn dan hypostatic bridges. En dan zijn dat soort bridges meer volwap nodig. En natuurlijk zijn de sensors welkant, in order te monitoriseren in onze hoofdpartijs, in order om alle infrastructuur te controleren. En ik denk dat de vervolkingen meer of meer dezelfde zijn. Ik geloof het. Dank je wel.