A formal description of a database consists of the description of the relations (tables) of the database together with the constraints that must hold on the database. Furthermore the contents of a database can be retrieved using queries. These constraints and queries for databases can very well be formalized. A formal description of a constraint or a query is necessary to describe the constraint or query unambiguously. In other words, a formal description leads to one and only one meaning of the constraint or query. To describe constraints and queries in a formal way we use predicate logic, set theory and tuple relational calculus. The tuple relational calculus is a calculus based on the use of tuple variables. A tuple variable is a variable that ranges over a named relation (i.e. a set of tuples of a relation). This paper describes the use of the relational calculus for databases. A description of the formal notation is given as well as a mapping of these expressions to SQL.
Study design: A secondary analysis of a systematic review. Background: Manipulations or mobilizations are commonly used interventions in patients with mechanical neck pain. The treatment effects have often been studied in randomized controlled trials (RCT) which are generally considered the gold standard in evaluating the treatment effects, mainly due to its high internal validity. External validity is defined as the extent to which the effects can be generalised to clinical practice. An important prerequisite for this is that interventions used in clinical trials can be replicated in clinical practice. It can be questioned if interventions utilized in randomized controlled trials can be translated into clinical practice. Objectives: The overall aim of this study is to examine whether the quality of the description of manipulation and mobilization interventions is sufficient for to replication of these interventions in clinical practice. Methods: A comprehensive literature search was performed. Two independent researchers used the Template for Intervention Description and Replication (TIDieR) which is a 12-item checklist for describing the completeness of the interventions. Results: Sixty-seven articles were included that used manipulation and/or mobilization interventions for patients with mechanical neck pain. None of the articles describe the intervention e.g. all the items on the TIDieR list. Considering item 8 (a-f) of the TIDieR checklist only one article described the used techniques completely. Conclusion: Manipulation or a mobilization interventions are poorly reported in RCTs, which jeopardize the external validity of RCTs, making it difficult for clinicians and researchers to replicate these interventions.
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298 woorden: In the upcoming years the whole concept of mobility will radically change. Decentralization of energy generation, urbanization, digitalization of processes, electrification of vehicles and shared mobility are only some trends which have a strong influence on future mobility. Furthermore, due to the shift towards renewable energy production, the public and the private sector are required to develop new infrastructures, new policies as well as new business models. There are countless opportunities for innovative business models emerging. Companies in this field – such as charging solution provider, project management or consulting companies that are part of this project, Heliox and Over Morgen respectively – are challenged with countless possibilities and increasing complexity. How to overcome this problem? Academic research proposes a promising approach, namely the use of business model patterns for business model innovation. In short, these business model patterns are descriptions of proven practical solutions to common business model challenges. An example for a general pattern would be the business model pattern “Consumables”. It describes how to lock in a customer into an ecosystem by using a subsidized basic product and complement it with overpriced consumables. This pattern works really well and has been used by many companies (e.g. Senseo, HP, or Gillette). To support the business model innovation process of Heliox and Over Morgen as well as companies in the electric mobility space in general, we propose to systematically consolidate and develop business model patterns for the electric mobility sector and to create a database. Electric mobility patterns could not only foster creativity in the business model innovation process but also enhance collaboration in teams. By having a classified list of business model pattern for electric mobility, practitioners are equipped which a heuristic tool to create, extend and revise business models for the future.
The PhD research by Joris Weijdom studies the impact of collective embodied design techniques in collaborative mixed-reality environments (CMRE) in art- and engineering design practice and education. He aims to stimulate invention and innovation from an early stage of the collective design process.Joris combines theory and practice from the performing arts, human-computer interaction, and engineering to develop CMRE configurations, strategies for its creative implementation, and an embodied immersive learning pedagogy for students and professionals.This lecture was given at the Transmedia Arts seminar of the Mahindra Humanities Center of Harvard University. In this lecture, Joris Weijdom discusses critical concepts, such as embodiment, presence, and immersion, that concern mixed-reality design in the performing arts. He introduces examples from his practice and interdisciplinary projects of other artists.About the researchMultiple research areas now support the idea that embodiment is an underpinning of cognition, suggesting new discovery and learning approaches through full-body engagement with the virtual environment. Furthermore, improvisation and immediate reflection on the experience itself, common creative strategies in artist training and practice, are central when inventing something new. In this research, a new embodied design method, entitled Performative prototyping, has been developed to enable interdisciplinary collective design processes in CMRE’s and offers a vocabulary of multiple perspectives to reflect on its outcomes.Studies also find that engineering education values creativity in design processes, but often disregards the potential of full-body improvisation in generating and refining ideas. Conversely, artists lack the technical know-how to utilize mixed-reality technologies in their design process. This know-how from multiple disciplines is thus combined and explored in this research, connecting concepts and discourse from human-computer interaction and media- and performance studies.This research is a collaboration of the University of Twente, Utrecht University, and HKU University of the Arts Utrecht. This research is partly financed by the Dutch Research Council (NWO).Mixed-reality experiences merge real and virtual environments in which physical and digital spaces, objects, and actors co-exist and interact in real-time. Collaborative Mix-Reality Environments, or CMRE's, enable creative design- and learning processes through full-body interaction with spatial manifestations of mediated ideas and concepts, as live-puppeteered or automated real-time computer-generated content. It employs large-scale projection mapping techniques, motion-capture, augmented- and virtual reality technologies, and networked real-time 3D environments in various inter-connected configurations.This keynote was given at the IETM Plenary meeting in Amsterdam for more than 500 theatre and performing arts professionals. It addresses the following questions in a roller coaster ride of thought-provoking ideas and examples from the world of technology, media, and theatre:What do current developments like Mixed Reality, Transmedia, and The Internet of Things mean for telling stories and creating theatrical experiences? How do we design performances on multiple "stages" and relate to our audiences when they become co-creators?Contactjoris.weijdom@hku.nl / LinkedIn profileThis research is part of the professorship Performative Processes
Despite the benefits of the widespread deployment of diverse Internet-enabled devices such as IP cameras and smart home appliances - the so-called Internet of Things (IoT) has amplified the attack surface that is being leveraged by cyber criminals. While manufacturers and vendors keep deploying new products, infected devices can be counted in the millions and spreading at an alarming rate all over consumer and business networks. The objective of this project is twofold: (i) to explain the causes behind these infections and the inherent insecurity of the IoT paradigm by exploring innovative data analytics as applied to raw cyber security data; and (ii) to promote effective remediation mechanisms that mitigate the threat of the currently vulnerable and infected IoT devices. By performing large-scale passive and active measurements, this project will allow the characterization and attribution of compromise IoT devices. Understanding the type of devices that are getting compromised and the reasons behind the attacker’s intention is essential to design effective countermeasures. This project will build on the state of the art in information theoretic data mining (e.g., using the minimum description length and maximum entropy principles), statistical pattern mining, and interactive data exploration and analytics to create a casual model that allows explaining the attacker’s tactics and techniques. The project will research formal correlation methods rooted in stochastic data assemblies between IoT-relevant measurements and IoT malware binaries as captured by an IoT-specific honeypot to aid in the attribution and thus the remediation objective. Research outcomes of this project will benefit society in addressing important IoT security problems before manufacturers saturate the market with ostensibly useful and innovative gadgets that lack sufficient security features, thus being vulnerable to attacks and malware infestations, which can turn them into rogue agents. However, the insights gained will not be limited to the attacker behavior and attribution, but also to the remediation of the infected devices. Based on a casual model and output of the correlation analyses, this project will follow an innovative approach to understand the remediation impact of malware notifications by conducting a longitudinal quasi-experimental analysis. The quasi-experimental analyses will examine remediation rates of infected/vulnerable IoT devices in order to make better inferences about the impact of the characteristics of the notification and infected user’s reaction. The research will provide new perspectives, information, insights, and approaches to vulnerability and malware notifications that differ from the previous reliance on models calibrated with cross-sectional analysis. This project will enable more robust use of longitudinal estimates based on documented remediation change. Project results and methods will enhance the capacity of Internet intermediaries (e.g., ISPs and hosting providers) to better handle abuse/vulnerability reporting which in turn will serve as a preemptive countermeasure. The data and methods will allow to investigate the behavior of infected individuals and firms at a microscopic scale and reveal the causal relations among infections, human factor and remediation.
