Nantes, France


Nantes, France
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Lahrech R.,CSTB | Fery A.,CSTB | Gautier A.,Solamen SAS | Lecointre W.,CETE OUEST
Proceedings of BS 2013: 13th Conference of the International Building Performance Simulation Association | Year: 2013

The purpose of this study is to assess the capabilities of a thermal model to represent actual building energy consumption when trying to best fit the input data of the model to the actual data of the building in operation. The approach has been applied to a building for which many factors affecting energy use have been monitored for a whole year. Beyond detailed inspection and advanced investigation have been carried on to assess some uncertain parameters. The objective is also accounting for difficulties related to the inspection of a building in use. The results show the importance of sensitivity and uncertainty analysis on the evaluation of the energy consumption of buildings; within the probalistic frame, energy consumption calculation no more provides a single point estimate but rather a prediction interval with a distribution of the probability density. The study shows the difficulty of collecting and estimating the necessary parameters for the calculation model inputs for existing buildings in operation despite a strong investigation of inspection. Estimation of uncertainty of these parameters is also a long process that needs a strong knowledge. The overlap of distribution curve of the probability density of energy consumption for the case study between calculation and measurement is done on a small range which is outside the 90/90 tolerance interval of calculation. The main reason seems to be related to the difficulty to reproduce operating principles of HVAC systems into modeling (operating principles of air handling units for this case study) and difficulty to reproduce the real dynamic loads due to their complexity and diversity; many assumptions are used to estimate some of them, others were certainly not taken into account. Adjusting parameters of building energy simulation model into a calibration process allows to fit the model results to real situation of the building. It's helpful for energy efficiency services such as periodic verification of the energy performance of the building and continuous operation optimisation. In this field, sensitivity analysis method is necessary in the calibration process to orient the data collection work and to guide the parameters adjustment process [13]. Copyright © 2011 by IPAC'11/EPS-AG.

Cremona C.,SETRA CTOA | Poulin B.,CETE Ouest | Colas A.-S.,University Paris Est Creteil | Michel J.,SETRA CTOA | And 4 more authors.
Assessment, Upgrading and Refurbishment of Infrastructures | Year: 2013

The design codes use safety margins which, in general, exceed those that are reasonable to accept for the assessment of existing bridges. Knowledge about a structure can be improved by further investigations and this can justify modifying partial safety factors. In this context, the Technical Centre for Bridge Engineering (CTOA) of the Technical Department for Roads, Road Safety and Bridges (SETRA) has initiated in 2009 a large study for the calibration of partial factors adapted to the assessment of existing bridges. Based on the reliability theory, its objective is to provide modified partial factors based on tabulated experimental in-situ results. The study is performed on different families of standard bridges but the present paper will only highlight the preliminary results obtained for reinforced concrete slab bridges.

Guilbert D.,CETE Ouest | Guilbert D.,University Paris Est Creteil | Le Bastard C.,CETE Ouest | Le Bastard C.,University Paris Est Creteil | And 2 more authors.
IEEE Intelligent Vehicles Symposium, Proceedings | Year: 2013

Traffic congestion has led to research on how to use the existing infrastructure more efficiently. The experimental platform SAROT was constructed to allow traffic analysis but also to test new algorithms for traffic modeling and management. Origin-Destination (OD) Matrix is one of the most important traffic information for Intelligent Traffic System. By using the experimental platform SAROT, we want to test algorithms for OD Matrix. To obtain OD matrix, we need to get useful and accurate data by tracking vehicles. Two approaches for tracking vehicles by using Inductive Loop Detector (ILD) are used. Both approaches are computed on real traffic data set and compared. We use threshold decision to improve the correct matching rate for tracking vehicles. We propose a new methodology by associating two algorithms for increasing the correct matching rate. The new methodology was used to perform target OD matrix. © 2013 IEEE.

Humbert M.,CETE Ouest | Tasca-Guernouti S.,CETE Ouest | Berger J.,CETE Ouest | Lahrech R.,CSTB | Fery A.,CSTB
Proceedings of Building Simulation 2011: 12th Conference of International Building Performance Simulation Association | Year: 2011

The purpose of the CEBO research project is to propose a tool to assess the Effective Consumption of Occupied Buildings by calculation, which will be adjusted by measurement parameters that are limited in number and monitoring time. In this paper the method to identify the parameters that have to be measured is presented on a single family housing, using the TH-CE ex model (French regulation model for existing buildings). The method is based on uncertainty analysis with fractional factorial design. On the single family house test case, it appears that the weather data, then the set point temperature need to be measured.

Maritime Policy and Management | Year: 2013

The World Bank toolkit and its port administration models, particularly for landlord ports, have been inspiring port reforms around the world for many years. This includes the French port reform of 2008. This reform was implemented according to local conditions, and according to the activities of ports and terminals in comparison with other major European ports. This paper analyses the new organizations set-up and gives details about their features. Using the Matching Framework of existing literature, it assesses the degree to which the new structures and new strategies match. It contributes to the research about port reform, and stresses, as do the majority of other analyses that the landlord port model may require adjustments in specific situations. © 2013 Copyright Taylor and Francis Group, LLC.

Caucheteu A.,CETE Ouest | Stephan E.,CETE Ouest
Proceedings of BS 2013: 13th Conference of the International Building Performance Simulation Association | Year: 2013

Calibration of Building Energy Simulation is an under-determined problem. There can be several correct solutions. The consequences of using the Building Energy Simulation for retrofit design can be significant. In this paper, we will propose a method that identifies different solutions in the entire field that was studied. It enables one to evaluate the uncertainty in energy saving estimations. The method uses an experimental design in order to reduce calculation time. It uses the coefficient of variation of root mean square error. We applied the method on an old building. The same retrofit design can yield a 40 to 60% savings in energy according to the chosen calibrated Building Energy Simulation. Copyright © 2011 by IPAC'11/EPS-AG.

Caucheteux A.,CETE Ouest | Es Sabar A.,CETE Ouest | Boucher V.,CETE Ouest
International Journal of Metrology and Quality Engineering | Year: 2013

Measuring the energy efficiency of buildings and its confrontation with the current Building Energy Simulations now faces knowledge of what is commonly called "occupancy". This work has been made in order to implement a monitoring system on a research demonstrator building at DLRCA in Angers (France). The goals were first to know the occupancy as input data of models but also to build occupancy models. Occupancy can be defined as all the action of occupants that affect building energy efficiency. The chosen monitoring deals with its presence, lightning, windows opening and internal gains. It seems that the use of an Infra-red detector allows a accuracy of 5 min in the detection of presence. The use of dry contact sensors allows the detection of five different rates of slide windows opening that can affect temperature decrease. Light sensors seem to be efficient to detect artificial lighting states when correctly configured. © 2013 EDP Sciences.

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