Eindhoven University of Technology

About: Eindhoven University of Technology is a education organization based out in Eindhoven, Noord-Brabant, Netherlands. It is known for research contribution in the topics: Catalysis & Computer science. The organization has 22309 authors who have published 52936 publications receiving 1584164 citations. The organization is also known as: Technische Hogeschool Eindhoven & TU/e.

Discovering block-structured process models from event logs - a constructive approach

Abstract: Process discovery is the problem of, given a log of observed behaviour, finding a process model that 'best' describes this behaviour. A large variety of process discovery algorithms has been proposed. However, no existing algorithm guarantees to return a fitting model (i.e., able to reproduce all observed behaviour) that is sound (free of deadlocks and other anomalies) in finite time. We present an extensible framework to discover from any given log a set of block-structured process models that are sound and fit the observed behaviour. In addition we characterise the minimal information required in the log to rediscover a particular process model. We then provide a polynomial-time algorithm for discovering a sound, fitting, block-structured model from any given log; we give sufficient conditions on the log for which our algorithm returns a model that is language-equivalent to the process model underlying the log, including unseen behaviour. The technique is implemented in a prototypical tool.

Forty years of Fanger's model of thermal comfort: comfort for all?

Abstract: The predicted mean vote (PMV) model of thermal comfort, created by Fanger in the late 1960s, is used worldwide to assess thermal comfort. Fanger based his model on college-aged students for use in invariant environmental conditions in air-conditioned buildings in moderate thermal climate zones. Environmental engineering practice calls for a predictive method that is applicable to all types of people in any kind of building in every climate zone. In this publication, existing support and criticism, as well as modifications to the PMV model are discussed in light of the requirements by environmental engineering practice in the 21st century in order to move from a predicted mean vote to comfort for all. Improved prediction of thermal comfort can be achieved through improving the validity of the PMV model, better specification of the model's input parameters, and accounting for outdoor thermal conditions and special groups. The application range of the PMV model can be enlarged, for instance, by using the model to assess the effects of the thermal environment on productivity and behavior, and interactions with other indoor environmental parameters, and the use of information and communication technologies. Even with such modifications to thermal comfort evaluation, thermal comfort for all can only be achieved when occupants have effective control over their own thermal environment.

A low-bandgap semiconducting polymer for photovoltaic devices and infrared emitting diodes

Abstract: A novel low-bandgap conjugated polymer (PTPTB, E-g = similar to1.6 eV), consisting of alternating electron-rich N-dodecyl-2,5-bis(2'-thienyl)pyrrole (TPT) and electron-deficient 2,1,3-benzothiadiazole (B) units, is introduced for thin-film optoelectronic devices working in the near infrared (NIR). Bulk heterojunction photovoltaic cells from solid-state composite films of PTPTB with the soluble fullerene derivative [6,6]-phenyl C-61 butyric acid methyl ester (PCBM) as an active layer shows promising power conversion efficiencies up to 1% under AM1.5 illumination. Furthermore, electroluminescent devices (light-emitting diodes) from thin films of pristine PTPTB show near infrared emission peaking at 800 nm with a turn on voltage below 4 V. The electroluminescence can be significantly enhanced by sensitization of this material with a wide bandgap material such as the poly(p-phenylene vinylene) derivative MDMO-PPV.

Lipid-based nanoparticles for contrast-enhanced MRI and molecular imaging.

Abstract: In the field of MR imaging and especially in the emerging field of cellular and molecular MR imaging, flexible strategies to synthesize contrast agents that can be manipulated in terms of size and composition and that can be easily conjugated with targeting ligands are required. Furthermore, the relaxivity of the contrast agents, especially for molecular imaging applications, should be very high to deal with the low sensitivity of MRI. Lipid-based nanoparticles, such as liposomes or micelles, have been used extensively in recent decades as drug carrier vehicles. A relatively new and promising application of lipidic nanoparticles is their use as multimodal MR contrast agents. Lipids are amphiphilic molecules with both a hydrophobic and a hydrophilic part, which spontaneously assemble into aggregates in an aqueous environment. In these aggregates, the amphiphiles are arranged such that the hydrophobic parts cluster together and the hydrophilic parts face the water. In the low concentration regime, a wide variety of structures can be formed, ranging from spherical micelles to disks or liposomes. Furthermore, a monolayer of lipids can serve as a shell to enclose a hydrophobic core. Hydrophobic iron oxide particles, quantum dots or perfluorocarbon emulsions can be solubilized using this approach. MR-detectable and fluorescent amphiphilic molecules can easily be incorporated in lipidic nanoparticles. Furthermore, targeting ligands can be conjugated to lipidic particles by incorporating lipids with a functional moiety to allow a specific interaction with molecular markers and to achieve accumulation of the particles at disease sites. In this review, an overview of different lipidic nanoparticles for use in MRI is given, with the main emphasis on Gd-based contrast agents. The mechanisms of particle formation, conjugation strategies and applications in the field of contrast-enhanced, cellular and molecular MRI are discussed.