Time filter

Source Type

Århus, Denmark

Jakobsen T.P.,Alexandra Institute | Makkes M.X.,TU Eindhoven | Nielsen J.D.,Alexandra Institute
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2010

We present an efficient implementation of the Orlandi protocol which is the first implementation of a protocol for multiparty computation on arithmetic circuits, which is secure against up to n-1 static, active adversaries. An efficient implementation of an actively secure self-trust protocol enables a number of multiparty computation where one or more of the parties only trust himself. Examples includes auctions, negotiations, and online gaming. The efficiency of the implementation is largely obtained through an efficient implementation of the Paillier cryptosystem, also described in this paper. © 2010 Springer-Verlag Berlin Heidelberg. Source

Verdezoto N.,University of Aarhus | Olsen J.W.,Alexandra Institute
IHI'12 - Proceedings of the 2nd ACM SIGHIT International Health Informatics Symposium | Year: 2012

Several technologies have been developed to support people's medication management, including pillboxes, specialized software applications, reminders and paper-based medication lists. Several of these technologies were discovered in older adults' homes during user studies carried out with the main purpose to help them to manage their medications and recall challenges. We confirm that a considerable number of older adults integrate their medication treatments into their daily life routines, and that the lack of knowledge, caregiver's support, medicine outside the home, forgetting medication intake, complexity of medication regimen were equally important challenges. One of the major findings was the issue related to substitutions, as older adults get confused due to the volatile information that they receive regarding their medications. We define basic requirements in order to address these issues towards the design of a personalized medication management system. We further describe our initial stage in a participatory design process as part of the ongoing Lev Vel Consortium. Copyright © 2012 ACM. Source

Andersen E.S.,Aarhus University Hospital | Noe K.O.,University of Aarhus | Noe K.O.,Alexandra Institute | Sorensen T.S.,University of Aarhus | And 6 more authors.
Radiotherapy and Oncology | Year: 2013

Background and purpose: Variations in organ position, shape, and volume cause uncertainties in dose assessment for brachytherapy (BT) in cervix cancer. The purpose of this study was to evaluate uncertainties associated with bladder dose accumulation based on DVH parameter addition (previously called "the worst case assumption") in fractionated BT. Materials and methods: Forty-seven patients treated for locally advanced cervical cancer were included. All patients received EBRT combined with two individually planned 3D image-guided adaptive BT fractions. D2cm 3 and D0.1 cm 3were estimated by DVH parameter addition and compared to dose accumulations based on an in-house developed biomechanical deformable image registration (DIR) algorithm. Results: DIR-based DVH analysis was possible in 42/47 patients. DVH parameter addition resulted in mean dose deviations relative to DIR of 0.4 ± 0.3 Gyαβ3 (1.5 ± 1.8%) and 1.9 ± 1.6 Gyαβ3 (5.2 ± 4.2%) for D2cm 3 and D0.1cm 3 respectively. Dose deviations greater than 5% occurred in 2% and 38% of the patients for D2 cm 3 and D0.1cm 3 respectively. Visual inspection of the dose distributions showed that hotspots were located in the same region of the bladder during both BT fractions for the majority of patients. Conclusion: DVH parameter addition provides a good estimate for D2cm 3 whereas D0.1cm 3 is less robust to this approximation. © 2013 Elsevier Ireland Ltd. All rights reserved. Source

Dalgaard L.G.,Alexandra Institute | Gronvall E.,University of Aarhus | Verdezoto N.,University of Aarhus
Proceedings of the 2013 7th International Conference on Pervasive Computing Technologies for Healthcare and Workshops, PervasiveHealth 2013 | Year: 2013

Several projects have shown that self-management of medication in private homes can be challenging. Many projects focused on specific illness-related approaches (e.g. diabetes) or practical issues such as how to handle medication while travelling. However, designing for everyday medication management involves more than just specific illness-related strategies and should take into account the broad set of activities conforming people's everyday life. This study investigates how older adults manage their medication in everyday life. To inform the design of pervasive healthcare medication management systems (PHMMS), the study calls for attention to medication-specific particularities that account for: according to need medication, the heterogeneous care network, the substitute medication, the medication informational order, the shared responsibility and the adjustment of medication intake. These medication particularities can enhance the individual's medication overview and support the understanding of medication intake in everyday life. The study also presents five design principles for future design of PHMMS. © 2013 ICST. Source

Neerbek J.,Alexandra Institute
ACM International Conference Proceeding Series | Year: 2012

Frequent itemset mining finds frequently occurring itemsets in transactional data. This is applied to diverse problems such as decision support, selective marketing, financial forecast and medical diagnosis. The cloud, computation as an utility service, allows us to crunch large mining problems. There are a number of algorithms for doing frequent itemset mining, but none are out-of-the-box suited for the cloud, requiring large data structures to be synchronized across the network. One of the best algorithms for doing frequent itemset mining is the known FP-growth (Frequent Patterns growth). We develop a cloud-enabled algorithmic variant for frequent itemset mining that scales with very little communication and computational overhead and even, with only one worker node, is faster than FP-growth. We develop the concept of a postfix path and show how this allows us to lower the communicational cost and leads to adjustable work sizes. This concept provides a very exible algorithmic solution that can be applied to a wide variety of different problem sizes and setups. Copyright 2012 ACM. Source

Discover hidden collaborations