Online Spatio-Temporal Learning with Target Projection

Recurrent neural networks trained with the backpropagation through time (BPTT) algorithm have led to astounding successes in various temporal tasks. However, BPTT introduces severe limitations, such as the requirement to propagate information backwards through time, the weight symmetry requirement, as well as update-locking in space and time....

Ground vibration testing and fem model updating of scaled Diana 2 glider model using accelerometer, gyro and strain measurements

A ground vibration test was conducted with a 1:3 scaled Diana 2 glider model where the modal parameters were estimated using the accelerometers, gyroscopes and strain gauges integrated in the test aircraft and validated using externally attached calibrated accelerometers and commercial software. These modal parameters were then used to update...

No-Directional and Backward-Leak Uni-Directional Updatable Encryption Are Equivalent

Updatable encryption (UE) enables the cloud server to update the previously sourced encrypted data to a new key with only an update token received from the client. Two interesting works have been proposed to clarify the relationships among various UE security notions. Jiang (ASIACRYPT 2020) proved the equivalence of every security notion in...

Large-Scale ADS-B Data and Signal Quality Analysis

To investigate the contradicting findings of previous studies that investigated ADS-B quality, a study was per-formed to analyze the data and signal quality of ADS-B. For this study, a large dataset of raw ADS-B messages was analyzed, regarding the quality of the data and the signal, differentiating between internal and external sources of...

Challenges for Updating 3D Cadastral Objects using LiDAR and Image-based Point Clouds

Nowadays due to the increasing complex and multifunctional building environment in the urban areas it is required an accurate geometry and proper legal registration of the cadastral objects including third dimension and time aspect. 2D land-parcel data seems insufficient to address the variety of problems in high density residential areas. This...

EuroSDR: The pan european network for mapping agencies and academia

EuroSDR (http://www.eurosdr.net/) is a non-profit organisation that provides a pan-European network that brings together mapping / cadastre agencies and academia for the purpose of applied research, and securing timely, research-based knowledge that allows the agencies to play their role as content providers and government competence centres...

Incorporating Observations to Update the Piping Reliability Estimate of the Francis Levee

Piping failure of levees is one of the main contributors to flood risk. Piping occurs when the head difference over a levee results in uplift of the inland blanket, followed by backward erosion in the aquifer due to high local flow velocities. Whether piping occurs, highly depends on local geo-hydrological circumstances which are uncertain due...

Computing the Reliability of Shallow Foundations with Spatially Distributed Measurements

In many geotechnical projects, field data is used to determine the soil parameters. In most instances, however, the statistical analysis is performed ad hoc and the spatial distribution of this data is not (expclitly) accounted for. A more formal statistical approach allows to make better use of the data and combine it in a consistent manner...

Assessment of the homogeneity of volunteered geographic information in South Africa

The potential for volunteer groups to contribute geographic data to National Mapping Agencies has been widely recognised. Several investigations have been done to determine the geometric accuracy of this data for the purposes of national mapping. Beyond accuracy, from a production perspective National Mapping Agencies will also be interested in...

Re-assessing reliability based on survived loads

The reliability of flood defenses is often dictated by large uncertainties in the hydraulic loading and the structural resistance. Additional information decreases uncertainty, however, acquiring it is often costly. One source of information, even though in many cases readily available, is hardly used – survived loads. This article shows how...

Automatic object recognition and change detection of urban trees

Monitoring of tree objects is relevant in many current policy issues and relate to the quality of the public space, municipal urban green management, management fees for green areas or Kyoto protocol reporting and all have one thing in common: the need for an up to date tree database. This study, part of the Tree and Image research project,...

Updating piping probabilities with survived historical loads

Piping, also called under-seepage, is an internal erosion mechanism, which can cause the failure of dikes or other flood defence structures. The uncertainty in the resistance of a flood defence against piping is usually large, causing high probabilities of failure for this mechanism. A considerable part of this uncertainty is of epistemic nature...

Improving 2D change detection by using available 3D data

Change detection with very high resolution imagery is difficult, because 3D objects as buildings appear differently in 2D imagery due to varying viewing angles and sun positions. This research proposes a method to improve change detection by using simple 3D models of buildings. Buildings have been modelled as flat roof or gable roof buildings....

Using perspective guidance overlay to improve UAV manual control performance

The guidance information that is available to the UAV operator typically suffers from limitations of data update rate and system latency. Even when using a flight director command display, the manual control task is considerably more difficult compared to piloting a manned aircraft. Results from earlier research into perspective guidance...

The Stability of Paths in a Dynamic Network