@inproceedings{WenningerBayerlMaieretal.2021, author = {Wenninger, Marc and Bayerl, Sebastian P. and Maier, Andreas and Schmidt, Jochen}, title = {Recurrence Plot Spacial Pyramid Pooling Network for Appliance Identification in Non-Intrusive Load Monitoring}, series = {2021 20th IEEE International Conference on Machine Learning and Applications (ICMLA)}, booktitle = {2021 20th IEEE International Conference on Machine Learning and Applications (ICMLA)}, pages = {108 -- 115}, year = {2021}, abstract = {Parameter free Non-intrusive Load Monitoring (NILM) algorithms are a major step toward real-world NILM scenarios. The identification of appliances is the key element in NILM. The task consists of identification of the appliance category and its current state. In this paper, we present a param- eter free appliance identification algorithm for NILM using a 2D representation of time series known as unthresholded Recurrence Plots (RP) for appliance category identification. One cycle of voltage and current (V-I trajectory) are transformed into a RP and classified using a Spacial Pyramid Pooling Convolutional Neural Network architecture. The performance of our approach is evaluated on the three public datasets COOLL, PLAID and WHITEDv1.1 and compared to previous publications. We show that compared to other approaches using our architecture no initial parameters have to be manually tuned for each specific dataset.}, language = {en} } @inproceedings{BayerlWenningerSchmidtetal.2021, author = {Bayerl, Sebastian P. and Wenninger, Marc and Schmidt, Jochen and Wolff von Gudenberg, Alexander and Riedhammer, Korbinian}, title = {STAN: A stuttering therapy analysis helper}, series = {2021 IEEE Spoken Language Technology Workshop (SLT)}, booktitle = {2021 IEEE Spoken Language Technology Workshop (SLT)}, pages = {2}, year = {2021}, abstract = {Stuttering is a complex speech disorder identified by repetitions, prolongations of sounds, syllables or words and blockswhile speaking. Specific stuttering behaviour differs strongly,thus needing personalized therapy. Therapy sessions requirea high level of concentration by the therapist. We introduce STAN, a system to aid speech therapists in stuttering therapysessions. Such an automated feedback system can lower the cognitive load on the therapist and thereby enable a more consistent therapy as well as allowing analysis of stuttering over the span of multiple therapy sessions.}, language = {en} } @inproceedings{SchmidtWongYeap2006, author = {Schmidt, Jochen and Wong, C.K. and Yeap, W.K.}, title = {Mapping and Localisation with Sparse Range Data}, series = {International Conference on Autonomous Robots and Agents (ICARA), pages 497-502, Palmerston North, New Zealand}, booktitle = {International Conference on Autonomous Robots and Agents (ICARA), pages 497-502, Palmerston North, New Zealand}, year = {2006}, abstract = {We present an approach for indoor mapping and localization with a mobile robot using sparse range data, without the need for solving the SLAM problem. The paper consists of two main parts. First, a split and merge based method for dividing a given metric map into distinct regions is presented, thus creating a topological map in a metric framework. Spatial information extracted from this map is then used for self-localization. The robot computes local confidence maps for two simple localization strategies based on distance and relative orientation of regions. The local confidence maps are then fused using an approach adapted from computer vision to produce overall confidence maps. Experiments on data acquired by mobile robots equipped with sonar sensors are presented.}, language = {en} } @inproceedings{SchmidtWongYeap2006, author = {Schmidt, Jochen and Wong, C.K. and Yeap, W.K.}, title = {A Split \& Merge Approach to Metric-Topological Map-Building}, series = {International Conference on Pattern Recognition (ICPR), volume 3, pages 1069-1072, Hong Kong}, booktitle = {International Conference on Pattern Recognition (ICPR), volume 3, pages 1069-1072, Hong Kong}, year = {2006}, abstract = {We present a novel split and merge based method for dividing a given metric map into distinct regions, thus effectively creating a topological map on top of a metric one. The initial metric map is obtained from range data that are converted to a geometric map consisting of linear approximations of the indoor environment. The splitting is done using an objective function that computes the quality of a region, based on criteria such as the average region width (to distinguish big rooms from corridors) and overall direction (which accounts for sharp bends). A regularization term is used in order to avoid the formation of very small regions, which may originate from missing or unreliable sensor data. Experiments based on data acquired by a mobile robot equipped with sonar sensors are presented, which demonstrate the capabilities of the proposed method.}, language = {en} } @inproceedings{WongYeapSchmidt2006, author = {Wong, C.K. and Yeap, W.K. and Schmidt, Jochen}, title = {Computing a Network of ASRs Using a Mobile Robot Equipped with Sonar Sensors}, series = {International Conference on Robotics, Automation, and Mechatronics (RAM), pages 57-62, Bangkok, Thailand}, booktitle = {International Conference on Robotics, Automation, and Mechatronics (RAM), pages 57-62, Bangkok, Thailand}, year = {2006}, abstract = {This paper presents a novel algorithm for computing absolute space representations (ASRs) in Yeap, W.K. and Jefferies, M. (1988) for mobile robots equipped with sonar sensors and an odometer. The robot is allowed to wander freely (i.e. without following any fixed path) along the corridors in an office environment from a given start point to an end point. It then wanders from the end point back to the start point. The resulting ASRs computed in both directions are shown}, language = {en} } @inproceedings{YeapWongSchmidt2006, author = {Yeap, W.K. and Wong, C.K. and Schmidt, Jochen}, title = {Initial Experiments with a Mobile Robot on Cognitive Mapping}, series = {International Symposium on Practical Cognitive Agents and Robots (PCAR 2006), pages 221-230, Perth, Australia}, booktitle = {International Symposium on Practical Cognitive Agents and Robots (PCAR 2006), pages 221-230, Perth, Australia}, year = {2006}, abstract = {This paper shows how a mobile robot equipped with sonar sensors and an odometer is used to test ideas about cognitive mapping. The robot first explores an office environment and computes a "cognitive map" which is a network of ASRs [1]. The robot generates two networks, one for the outward journey and the other for the journey home. It is shown that both networks are different. The two networks, however, are not merged to form a single network. Instead, the robot attempts to use distance information implicit in the shape of each ASR to find its way home. At random positions in the homeward journey, the robot calculates its orientation towards home. The robot's performances for both problems are evaluated and found to be surprisingly accurate.}, language = {en} } @inproceedings{SchmidtWongYeap2007, author = {Schmidt, Jochen and Wong, C.K. and Yeap, W.K.}, title = {Spatial Information Extraction for Cognitive Mapping with a Mobile Robot.}, series = {Conference on Spatial Information Theory: COSIT'07, Melbourne, Australia. Volume 4736 of Lecture Notes in Computer Science}, booktitle = {Conference on Spatial Information Theory: COSIT'07, Melbourne, Australia. Volume 4736 of Lecture Notes in Computer Science}, year = {2007}, abstract = {When animals (including humans) first explore a new environment, what they remember is fragmentary knowledge about the places visited. Yet, they have to use such fragmentary knowledge to find their way home. Humans naturally use more powerful heuristics while lower animals have shown to develop a variety of methods that tend to utilize two key pieces of information, namely distance and orientation information. Their methods differ depending on how they sense their environment. Could a mobile robot be used to investigate the nature of such a process, commonly referred to in the psychological literature as cognitive mapping? What might be computed in the initial explorations and how is the resulting "cognitive map" be used for localization? In this paper, we present an approach using a mobile robot to generate a "cognitive map", the main focus being on experiments conducted in large spaces that the robot cannot apprehend at once due to the very limited range of its sensors. The robot computes a "cognitive map" and uses distance and orientation information for localization.}, language = {en} } @inproceedings{WongYeapSchmidt2007, author = {Wong, C.K. and Yeap, W.K. and Schmidt, Jochen}, title = {Using a Mobile Robot for Cognitive Mapping}, series = {International Joint Conference on Artificial Intelligence (IJCAI), pages 2243-2248, Hyderabad, India, 2007}, booktitle = {International Joint Conference on Artificial Intelligence (IJCAI), pages 2243-2248, Hyderabad, India, 2007}, year = {2007}, abstract = {When animals (including humans) first explore a new environment, what they remember is fragmentary knowledge about the places visited. Yet, they have to use such fragmentary knowledge to find their way home. Humans naturally use more powerful heuristics while lower animals have shown to developa varietyof methodsthat tend to utilize two key pieces of information,namely distance and orientation information. Their methods differ depending on how they sense their environment. Could a mobile robot be used to investigate the nature of such a process, commonly referred to in the psychological literature as cognitive mapping? What might be computed in the initial explorations and how is the resulting "cognitive map" be used to return home? In this paper, we presented a novel approach using a mobile robot to do cognitive mapping. Our robot computes a "cognitive map" and uses distance and orientation information to find its way home. The process developed provides interesting insights into the nature of cognitive mapping and encourages us to use a mobile robot to do cognitive mapping in the future, as opposed to its popular use in robot mapping.}, language = {en} } @inproceedings{SchmidtVogtNiemann2002, author = {Schmidt, Jochen and Vogt, F. and Niemann, H.}, title = {Nonlinear Refinement of Camera Parameters using an Endoscopic Surgery Robot}, series = {Proceedings of IAPR Conference on Machine Vision Applications (MVA)}, booktitle = {Proceedings of IAPR Conference on Machine Vision Applications (MVA)}, year = {2002}, abstract = {We present an Approach for non linea roptimization of the parameters of an endoscopic camera mounted on a surgery robot. The goal is to generate a depth map for each image in order to enhance the quality of medical light fields. The pose information provided by the robot is used as an initialization, where especially the orientation isi naccurate. Refinement of intrinsic and extrinsic camera parameters is performed by minimizing the back-projectionerror of 3-D points that are reconstructed by triangulation from image Feature stracked over an image sequence. Optimization of the camera parameters results in an enhancement of Rendering Quality in two ways: More accurate parameters lead to better interpolation as well as to better depth maps for approximating the scenegeometry.}, language = {en} } @inproceedings{SchmidtNiemannVogt2002, author = {Schmidt, Jochen and Niemann, H. and Vogt, F.}, title = {Dense Disparity Maps in Real-Time with an Application to Augmented Reality}, series = {Proceedings Sixth IEEE Workshop on Applications of Computer Vision (WACV 2002), pages 225-230, Orlando, FL USA}, booktitle = {Proceedings Sixth IEEE Workshop on Applications of Computer Vision (WACV 2002), pages 225-230, Orlando, FL USA}, year = {2002}, abstract = {This work presents a technique for computing dense disparity maps from a binocular stereo camera system. The methods are applied in an Augmented Reality setting for combining real and virtual worlds with proper occlusions. The proposed stereo correspondence technique is based oil area matching and facilitates an efficient strategy by using the concept of a three-dimensional similarity accumulator whereby occlusions are detected and object boundaries are extracted correctly. The main contribution of this paper is the way we fill the accumulator using absolute differences of images and computing a mean filter on these difference images. This. is. where the main advantages of the accumulator approach can be exploited, since all entries can be computed in parallel and thus extremely efficient. Additionally, we-perform an asymmetric correction step and a post-processing of the disparity maps that maintains object edges.}, language = {en} }