TY - CHAP A1 - Mecking, Simon A1 - Scheibengraber, Markus A1 - Kruse, Tobias A1 - Schanda, Ulrich A1 - Wellisch, Ulrich T1 - Energiebestimmung an Brettsperrholzbauteilen im Holzmassivbau T2 - Deutsche Gesellschaft für Akustik e.V. (ed.): Fortschritte der Akustik - DAGA 2017, 43. Deutsche Jahrestagung für Akustik, Kiel, Deutschland N2 - Ein Ziel des DFG-AiF-Clusterforschungsvorhabens Vibroakustik im Planungsprozess für Holzbauten ist die Reduktion des schalltechnischen Planungsaufwandes bei der Holzmassivbauweise. Hierzu soll das Prognoseverfahren der DIN EN 12354 angepasst werden. Darin ist ein vereinfachter SEA-Ansatz zugrunde gelegt, welcher diffuse Körperschallfelder in den Bauteilen sowie deren schwache Kopplung voraussetzt. Tatsächlich trifft die Annahme diffuser Körperschallfelder nur bei Bauteilen mit geringer Ausbreitungsdämpfung zu. Um ein Maß für die Kopplung der Bauteile zu erhalten, wird ein Energieverhältnis aus den Bauteilschnellen gebildet. In der DIN EN ISO 10848-1 wird eine Vorschrift für die Messung der mittleren Bauteilschnelle beschrieben. Daraus wird ein örtlich und zeitlich gemittelter Schnellepegel je Bauteil berechnet, mit dem die Energie des Bauteils bestimmt wird. In diesem Beitrag werden Messergebnisse von Körperschallfeldern an Brettsperrholzelementen im Hinblick auf die Energiebestimmung diskutiert. Bei der statistischen Auswertung werden die Anzahl der Anregepositionen und der Messpositionen auf dem direkt und indirekt angeregten Bauteil analysiert. In einem weiteren Schritt werden die erforderlichen Messpositionen durch eine geeignete Auswahl reduziert und mit den pauschalen, geometrischen Vorgaben der Messvorschrift aus der DIN EN ISO 10848-1 verglichen. Die Erkenntnisse werden zur Bewertung von Messergebnissen und für Empfehlungen an die Durchführung zukünftiger Messungen herangezogen. KW - Holzmassivbau KW - Schallmesstechnik Y1 - 2017 ER - TY - JOUR A1 - Mecking, Simon A1 - Scheibengraber, Markus A1 - Kruse, Tobias A1 - Schanda, Ulrich A1 - Wellisch, Ulrich T1 - Experimentally based statistical analysis of the vibrational energy of CLT building elements JF - 24th International Congress on Sound and Vibration, ICSV24, London, United Kingdom, July 2017 N2 - The method is based on a simplified Statistical Energy Analysis(SEA) approach. The energy ratios of various subsystems are the main quantities to predict sound transmission. The method has proven to work sufficiently accurate for masonry and concrete buildings, where the building components like walls, floors etc. can be regarded as rather homogeneous structures. To adapt this method for solid timber constructions it is necessary to prove that basic SEA requirements are fullfilled by orthotropic materials and heterogeneous structures that occur in these building types. In a case study, an isolated T-junction formed by Cross Laminated Timber(CLT) elements is experimentally investigated. The buildings elements are subdivided in segments with typical screwed connections. In the experiments the diffusivity of the vibration field is investigated, using point excitation with a shaker at several positions and many, randomly chosen response positions. MONTE-CARLO simulations are conducted for random but fix-sized subsets of the measured response positions to find the necessary number of response positions for an accurate determination of the vibrational energy. As a result the distribution of the mean velocity levels can be approximated. In a second approach a multiple linear regression model based on the least absolute shrinkage and selection operator(LASSO)is applied, because for lower frequency bands multicollinearity is expected. In the context of linear regression modelling, data-driven methods are used to select optimal subsets of response positions, to get an estimating equation. KW - Schallmesstechnik KW - CLT building Y1 - 2017 ER - TY - CHAP A1 - Hanfstaengl, Lucia A1 - Parzinger, Michael A1 - Spindler, Uli A1 - Wellisch, Ulrich A1 - Wirnsberger, Markus T1 - Identifying occupant presence in a room based on machine learning techniques by measuring indoor air conditions T2 - E3S Web of Conferences, 12th Nordic Symposium on Building Physics (NSB 2020) N2 - Knowing about the presence and number of people in a room can be of interest for precise control of heating, ventilation and air conditioning. To determine the number and presence of occupants cost-effectively, it is of interest to use already existing air condition sensors (temperature, humidity, CO2) of the building automation system. Different approaches and methods for determining presence have attracted attention in recent years. We propose an occupancy detection method based on a method of supervised machine learning. In an experiment, measurement data were recorded in a research apartment with controllable boundary conditions. The presence of people was simulated by artificial injection of water vapour, CO2 and heat dissipation. The variation of the number of artificial users, the duration of presence and the supply air volume flow of the ventilation resulted in a total of 720 combinations. By using artificial users, the boundary conditions were accurately defined, and different presence situations could be measured time-effectively. The data is evaluated with a method of supervised machine learning called random forest. The statistical model can determine precisely the number of people in over 93% of the cases in a disjoint test sample. The experiments took part in the Rosenheim Technical University of Applied Sciences laboratory. KW - occupancy KW - maschine learning KW - random forest Y1 - 2020 UR - https://doi.org/10.1051/e3sconf/202017222005 VL - 172 SP - 22005 ER - TY - JOUR A1 - Parzinger, Michael A1 - Hanfstaengl, Lucia A1 - Sigg, Ferdinand A1 - Spindler, Uli A1 - Wellisch, Ulrich A1 - Wirnsberger, Markus T1 - Residual Analysis of Predictive Modelling Data for Automated Fault Detection in Building’s Heating, Ventilation and Air Conditioning Systems JF - Sustainability N2 - Faults in Heating, Ventilation and Air Conditioning (HVAC) systems affect the energy efficiency of buildings. To date, there rarely exist methods to detect and diagnose faults during the operation of buildings that are both cost-effective and sufficient accurate. This study presents a method that uses artificial intelligence to automate the detection of faults in HVAC systems. The automated fault detection is based on a residual analysis of the predicted total heating power and the actual total heating power using an algorithm that aims to find an optimal decision rule for the determination of faults. The data for this study was provided by a detailed simulation of a residential case study house. A machine learning model and an ARX model predict the building operation. The model for fault detection is trained on a fault-free data set and then tested with a faulty operation. The algorithm for an optimal decision rule uses various statistical tests of residual properties such as the Sign Test, the Turning Point Test, the Box-Pierce Test and the Bartels-Rank Test. The results show that it is possible to predict faults for both known faults and unknown faults. The challenge is to find the optimal algorithm to determine the best decision rules. In the outlook of this study, further methods are presented that aim to solve this challenge. KW - fault detection KW - HVAC KW - residual analysis Y1 - 2020 UR - https://doi.org/10.3390/su12176758 VL - 12 IS - 17 SP - 6758 ER - TY - CHAP A1 - Parzinger, Michael A1 - Wellisch, Ulrich A1 - Hanfstaengl, Lucia A1 - Sigg, Ferdinand A1 - Wirnsberger, Markus A1 - Spindler, Uli T1 - Identifying faults in the building system based on model prediction and residuum analysis T2 - E3S Web of Conferences, 12th Nordic Symposium on Building Physics (NSB 2020) N2 - The energy efficiency of the building HVAC systems can be improved when faults in the running system are known. To this day, there are no cost-efficient, automatic methods that detect faults of the building HVAC systems to a satisfactory degree. This study induces a new method for fault detection that can replace a graphical, user-subjective evaluation of a building data measured on site with an automatic, data-based approach. This method can be a step towards cost-effective monitoring. For this research, the data from a detailed simulation of a residential case study house was used to compare a faultless operation of a building with a faulty operation. We argue that one can detect faults by analysing the properties of residuals of the prediction to the actual data. A machine learning model and an ARX model predict the building operation, and the method employs various statistical tests such as the Sign Test, the Turning Point Test, the Box-Pierce Test and the Bartels-Rank Test. The results show that the amount of data, the type and density of system faults significantly affect the accuracy of the prediction of faults. It became apparent that the challenge is to find a decision rule for the best combination of statistical tests on residuals to predict a fault. KW - fault detection KW - model prediction KW - HVAC KW - residuum analysis Y1 - 2020 UR - https://doi.org/10.1051/e3sconf/202017222001 VL - 172 SP - 22001 ER - TY - RPRT A1 - Sandor, V. A1 - Schalk, D. A1 - Sussmann, M. A1 - Wellisch, Ulrich T1 - Statistische Datenanalyse und Modellierung - Einsatzmöglichkeiten von Machine Learning Verfahren. Forschungsbericht 2016 Hochschule Rosenheim KW - Statistische Datenanalyse KW - Statistische Modellierung KW - Machine Learning Y1 - 2016 ER - TY - JOUR A1 - Frey, C. A1 - Schönfelder, F. A1 - Wellisch, Ulrich T1 - Anwendung von maschinellem Lernen in der Tarifierung JF - Der Aktuar KW - Maschinelles Lernen KW - Aktuarwissenschaften Y1 - 2016 ER - TY - CHAP A1 - Antretter, F. A1 - Mayer, C. A1 - Wellisch, Ulrich T1 - An approach for a statistical model for the user behaviour regarding window ventilation in residential buildings T2 - Proceedings of Building Simulation 2011: 12th Conference of International Building Performance Simulation Association, Sydney KW - Window Ventilation KW - Residential Buildings KW - Building Simulation Y1 - 2011 ER - TY - JOUR A1 - Steiger, S. A1 - Wellisch, Ulrich A1 - Hellwig, R. T. T1 - Untersuchung der Eignung verschiedener Fassaden für automatisierte Fensterlüftung in Schulen mit einem Entscheidungsbaumverfahren JF - Bauphysik N2 - Sollen Klassenräume über Fenster belüftet werden, kann dies über Stoßlüftung oder genau dosierte Dauerlüftung erfolgen. Messungen verschiedener Institutionen zeigen, dass die erforderliche regelmäßige Stoßlüftung in Schulen nicht praktiziert wird. Damit eine Dauerlüftung aber funktionieren kann, muss ermittelt werden, welcher Fenstertyp bei welcher Öffnungsweite bei behaglichen thermischen Verhältnissen im Raum den notwendigen Luftwechsel gewährleistet. Deshalb wurden an einem Freilandversuchsstand des Fraunhofer‐Instituts für Bauphysik Schwingflügel und Kippflügel auf ihre Eignung zur Dauerlüftung in Klassenräumen untersucht. Da sich bei den vielen Einflussfaktoren auf die freie Lüftung die deskriptive Analyse oft als sehr schwierig erweist, wird ein besonderes statistisches Verfahren, ein Entscheidungsbaumverfahren verwendet, das sowohl hinsichtlich der Auswahl der Einflussgrößen und der Modellüberanpassung sehr günstige statistischmethodische Eigenschaften besitzt. Mit diesem Verfahren können Einflussgrößen mit unterschiedlichen Skalenniveaus adäquat in die Auswertung einbezogen werden. Dabei erhält man ein intuitiv interpretierbares Regelwerk, welches dem Anwender einen erklärenden Einblick in die Zusammenhangsstruktur des untersuchten Prozesses liefert. KW - Fensterlüftung KW - Schulbelüftung KW - Raumthermik Y1 - 2010 ER - TY - RPRT A1 - Pruschka, H. A1 - Wellisch, Ulrich T1 - Asymptotic behaviour of estimation equations with functional nuisance or working parameter. N2 - We are concerned with the asymptotic theory of semiparametric estimation equations. We are dealing with estimation equations which have a parametric component of interest and a functional (nonparametric) nuisance component. We give sufficient conditions for the existence and the asymptotic normality of a consistent estimation equation estimator for the parameter of interest. These conditions concern the asymptotic distribution of the estimation function and of its derivative as well as the effect of the functional nuisance part in the estimation equation. In order to treat the nonparametric component we introduce a general differential calculus and a general mean value theorem. For the nonparametric part in the estimation equation we distinguish two cases: the situation of a (classical) nuisance parameter and the case of a so called working parameter. As a special case we get regularity conditions for estimation equations with finite dimensional nuisance or working parameter. As an example we present the semiparametric linear regression model. KW - Estimating equations KW - Asymptotic distribution KW - semiparametric linear regression model Y1 - 1997 ER -