Self-Supervised PPG Representation Learning Shows High Inter-Subject Variability

With the progress of sensor technology in wearables, the collection and analysis of PPG signals are gaining more interest. Using Machine Learning, the cardiac rhythm corresponding to PPG signals can be used to predict different tasks such as activity recognition, sleep stage detection, or more general health status. However, supervised...

Experimental and numerical validation of an inter-ply friction model for thermoset based fibre metal laminate under hot-pressing conditions

Hot-pressing can be an attractive fabrication method that enables the forming of hybrid materials like thermoset based fibre metal laminates. However, the process simulation on press forming requires accurate material characterization and boundary conditions to facilitate part design for a defect-free component. In order to improve the overall...

A Novel Engine Architecture for Low NOx Emissions

The fuel efficiency of turbofan engines has improved significantly, hence reducing aviation's CO2 emissions. However, the increased operating pressure and temperature for fuel efficiency cause adverse effects on NOx emissions. Therefore, a novel engine concept, which can reduce NOx emissions without affecting the cycle efficiency, is of high...

Comparison of Radar Receivers for OFDM and OTFS waveforms

A generic description for common multi-carrier radar receivers is proposed. Two multi-carrier waveforms - orthogonal frequency division multiplexing (OFDM) and orthogonal time-frequency spacing (OTFS) - which could be used for joint radar and communication (JRC) applications - are considered. Sensing performances of different waveform...

Understanding Actor Roles in Inter-organizational Digital Public Services

Different actor roles in inter-organizational digital public services are often neither understood nor acknowledged. This can result in challenges regarding the proper design and result in a lack of adoption of these services. In the literature, there exist various taxonomies outlining roles such as users, consumers or co-creators, although...

Inter-Organizational Co-Creation: An Approach to Support Energy Transition Projects

Societal challenges such as climate change and inefficiency of energysystems more and more crave for a sustainable environment. Research proved thatrestructuring energy systems into more sustainable forms, called “Energy Transition”, has faced challenges. How to deal with these challenges requires the cocreation between various actors with...

Defining and quantifying conversation quality in spontaneous interactions

Social interactions in general are multifaceted and there exists a wide set of factors and events that influence them. In this paper, we quantify social interactions with a holistic viewpoint on individual experiences, particularly focusing on non-task-directed spontaneous interactions. To achieve this, we design a novel perceived measure,...

Governance Challenges of Inter-organizational Digital Public Services Provisioning: A Case Study on Digital Invoicing Services in Belgium

Governments aim to digitalize public services. Whereas initially they worked in isolation, nowadays they increasingly link different building blocks together to realize integrated public services. This evolution poses challenges concerning the governance of public services. The purpose of this paper is to identify governance challenges in...

High Data-Rate Inter-Satellite Link (ISL) For Space-Based Interferometry

The inter-satellite link (ISL) in swarm and constellation missions is a key enabler in the autonomy of the mission. OLFAR (Orbiting Low Frequency Array for Radio astronomy) is one such mission where 10 to 50+ nanosatellites are placed in the Lunar orbit and perform astronomical observations from the far-side of the moon. Each of the...

A Comparative Study of Business-to-Government Information Sharing Arrangements for Tax Reporting

Having tax transparency is getting more important and enforced by more and more countries around the world. To deal with tax evasion, OECD has developed an Automatic Exchange of Information (AEOI) standard. The implementation of this standard differs among countries. In this study, we explore factors explaining the differences between two...

Low Latency IoT/M2M Using Nano-Satellites

Nano-satellite IoT/M2M missions are gaining popularity in recent time. Various companies have launched their pilot missions last year in 2018 and all these companies intend to place a constellation in (V)LEO that can communicate with low power sensors on the ground (sometimes remote locations) and relay it back to the end-user who is monitoring...

Steering the adoption of Standard Business Reporting for cross domain information exchange

Over the years, several governments around the world have introduced a version of Standard Business Reporting (SBR) for information exchange with public agencies. Their main goals are to ease the reporting burden for businesses and the regulatory burden for government agencies. This paper takes a look at the adoption numbers in the...

Multi-GNSS PPP-RTK: Mixed-receiver network and user scenarios

In this contribution, we present full-rank observation equations of the network and user receivers, of mixed types, through an application of S-system theory. We discuss the important roles played by the inter system biases (ISBs), and we show how the three-component structure of PPP-RTK is affected by the inclusion of the ISBs as extra...

Beyond informality: Traders as space experts in their own informal settlements

The spatial layout of built environments influences the distribution of commercial activities. As literature has shown, commercial activities can enhance the process of urban consolidation of informal areas (Hillier et al, 2000; Shafiei, 2007). The purpose of this paper is to investigate the correlation between spatial factors and the...

Relative state estimation and observability for formation flying satellites in the presence of sensor noise

This paper presents an investigation into the relative state estimation and observability for two formation flying satellites using two different relative navigation sensor sets. The first set consists out of a transmitter antenna on one satellite and a single receiver antenna on the other satellite to measure the inter-satellite range using a...

Space and crime in Dutch built environments: Macro and micro scale spatial conditions for residential burglaries and thefts from cars

At this moment, more knowledge is available on the physical characteristics of the built environment and their relationship to criminal opportunity rather than the spatial characteristics of potential targets and the public and private space between them. To improve this situation, a research project was started in the Dutch cities Gouda and...

In search for an appropriate granularity to model routing policies

VERVOERMIDDELENGEBRUIK IN HET WOON-WERKVERKEER VAN INWONERS UIT KLEINE KERNEN.; TRAVEL PATTERNS AND MODE USE OF COMMUTERS FROM SMALL TOWNS.