177 research outputs found
A review on AI Safety in highly automated driving
Remarkable progress in the fields of machine learning (ML) and artificial intelligence (AI) has led to an increased number of applications of (data-driven) AI systems for the partial or complete control of safety-critical systems. Recently, ML solutions have been particularly popular. Such approaches are often met with concerns regarding their correct and safe execution, which is often caused by missing knowledge or intransparency of their exact functionality. The investigation and derivation of methods for the safety assessment of AI systems are thus of great importance. Among others, these issues are addressed in the field of AI Safety. The aim of this work is to provide an overview of this field by means of a systematic literature review with special focus on the area of highly automated driving, as well as to present a selection of approaches and methods for the safety assessment of AI systems. Particularly, validation, verification, and testing are considered in light of this context. In the review process, two distinguished classes of approaches have been identified: On the one hand established methods, either referring to already published standards or well-established concepts from multiple research areas outside ML and AI. On the other hand newly developed approaches, including methods tailored to the scope of ML and AI which gained importance only in recent years
Reinforcement learning for safety-critical control of an automated vehicle
We present our approach for the development, validation and deployment of a
data-driven decision-making function for the automated control of a vehicle.
The decisionmaking function, based on an artificial neural network is trained
to steer the mobile robot SPIDER towards a predefined, static path to a target
point while avoiding collisions with obstacles along the path. The training is
conducted by means of proximal policy optimisation (PPO), a state of the art
algorithm from the field of reinforcement learning. The resulting controller is
validated using KPIs quantifying its capability to follow a given path and its
reactivity on perceived obstacles along the path. The corresponding tests are
carried out in the training environment. Additionally, the tests shall be
performed as well in the robotics situation Gazebo and in real world scenarios.
For the latter the controller is deployed on a FPGA-based development platform,
the FRACTAL platform, and integrated into the SPIDER software stack
Inhibition of the mevalonate pathway affects epigenetic regulation in cancer cells
The mevalonate pathway provides metabolites for post-translational modifications such as farnesylation, which are critical for the activity of RAS downstream signaling. Subsequently occurring regulatory processes can induce an aberrant stimulation of DNA methyltransferase (DNMT1) as well as changes in histone deacetylases (HDACs) and microRNAs in many cancer cell lines. Inhibitors of the mevalonate pathway are increasingly recognized as anticancer drugs. Extensive evidence indicates an intense cross-talk between signaling pathways, which affect growth, differentiation, and apoptosis either directly or indirectly via epigenetic mechanisms. Herein, we show data obtained by novel transcriptomic and corresponding methylomic or proteomic analyses from cell lines treated with pharmacologic doses of respective inhibitors (i.e., simvastatin, ibandronate). Metabolic pathways and their epigenetic consequences appear to be affected by a changed concentration of NADPH. Moreover, since the mevalonate metabolism is part of a signaling network, including vitamin D metabolism or fatty acid synthesis, the epigenetic activity of associated pathways is also presented. This emphasizes the far-reaching epigenetic impact of metabolic therapies on cancer cells and provides some explanation for clinical observations, which indicate the anticancer activity of statins and bisphosphonates
Application of the residue number system to the matrix multiplication problem
Due to the character of the original source materials and the nature of batch digitization, quality control issues may be present in this document. Please report any quality issues you encounter to [email protected], referencing the URI of the item.Includes bibliographical references.Not availabl
Reaction behaviour of dinuclear copper(I) complexes with m-xylyl-based ligands towards dioxygen
Intramolecular ligand hydroxylation was observed during the reactions of dioxygen with the dicopper(I) complexes of the ligands L1 (L1 = α,α'-bis[(2-pyridylethyl)amino]-m-xylene) and L3 (L3 = α,α'-bis[N-(2-pyridylethyl)-N-(2-pyridylmethyl)amino]-m-xylene). The dinuclear copper(I) complex [Cu2L3](ClO4)2 (3) and the dicopper(II) complex [Cu2(L1-O)(OH)(ClO4)]ClO4 (1) were characterized by single-crystal X-ray structure analysis. Furthermore, phenolate-bridged complexes were synthesized with the ligand L2-OH (structurally characterized [Cu2(L2-O)Cl3] (7) with L2 = α,α'-bis[N-methyl-N-(2-pyridylethyl)amino]-m-xylene; synthesized from the reaction between [Cu2(L2-O)(OH)](ClO4)2 (2) and Cl-) and Me-L3-OH: [Cu2(Me-L3-O)(μ -X)](ClO4)2·nH2O (Me-L3-OH = 2,6-bis[N-(2-pyridylethyl)-N-(2-pyridylmethyl)amino]-4-methylphenol and X = C3H3N2- (prz) (4), MeCO2- (5) and N3- (6)). The magnetochemical characteristics of compounds 4-7 were determined by temperature-dependent magnetic studies, revealing their antiferromagnetic behaviour [-2J (in cm-1) values: -92 for 4, -86 for 5 and -88 for 6; -374 for 7]
Arm swing responsiveness to dopaminergic medication in Parkinson’s disease depends on task complexity
The evidence of the responsiveness of dopaminergic medication on gait in patients with Parkinson’s disease is contradicting. This could be due to differences in complexity of the context gait was in performed. This study analysed the effect of dopaminergic medication on arm swing, an important movement during walking, in different contexts. Forty-five patients with Parkinson’s disease were measured when walking at preferred speed, fast speed, and dual-tasking conditions in both OFF and ON medication states. At preferred, and even more at fast speed, arm swing improved with medication. However, during dual-tasking, there were only small or even negative effects of medication on arm swing. Assuming that dual-task walking most closely reflects real-life situations, the results suggest that the effect of dopaminergic medication on mobility-relevant movements, such as arm swing, might be small in everyday conditions. This should motivate further studies to look at medication effects on mobility in Parkinson’s disease, as it could have highly relevant implications for Parkinson’s disease treatment and counselling
Non-global logarithms and jet algorithms in high-pT jet shapes
We consider jet-shape observables of the type proposed recently, where the
shapes of one or more high-pT jets, produced in a multi-jet event with definite
jet multiplicity, may be measured leaving other jets in the event unmeasured.
We point out the structure of the full next-to-leading logarithmic resummation
specifically including resummation of non-global logarithms in the leading-Nc
limit and emphasising their properties. We also point out differences between
jet algorithms in the context of soft gluon resummation for such observables.Comment: 22 pages, 4 figures. Title and a few words changed. Several typos
corrected. Version accepted by JHE
Machine Learning to Detect Alzheimer's Disease from Circulating Non-coding RNAs
Blood-borne small non-coding (sncRNAs) are among the prominent candidates for blood-based diagnostic tests. Often, high-throughput approaches are applied to discover biomarker signatures. These have to be validated in larger cohorts and evaluated by adequate statistical learning approaches. Previously, we published high-throughput sequencing based microRNA (miRNA) signatures in Alzheimer’s disease (AD) patients in the United States (US) and Germany. Here, we determined abundance levels of 21 known circulating miRNAs in 465 individuals encompassing AD patients and controls by RT-qPCR. We computed models to assess the relation between miRNA expression and phenotypes, gender, age, or disease severity (Mini-Mental State Examination; MMSE). Of the 21 miRNAs, expression levels of 20 miRNAs were consistently de-regulated in the US and German cohorts. 18 miRNAs were significantly correlated with neurodegeneration (Benjamini-Hochberg adjusted P < 0.05) with highest significance for miR-532-5p (Benjamini-Hochberg adjusted P = 4.8 × 10−30). Machine learning models reached an area under the curve (AUC) value of 87.6% in differentiating AD patients from controls. Further, ten miRNAs were significantly correlated with MMSE, in particular miR-26a/26b-5p (adjusted P = 0.0002). Interestingly, the miRNAs with lower abundance in AD were enriched in monocytes and T-helper cells, while those up-regulated in AD were enriched in serum, exosomes, cytotoxic t-cells, and B-cells. Our study represents the next important step in translational research for a miRNA-based AD test
A Thing of Beauty: Steering Behavior in an Interactive Playground
Interactive playgrounds are spaces where players engage in collocated, playful activities, in which added digital technology can be designed to promote cognitive, social, and motor skills development. To promote such development, different strategies can be used to implement game mechanics that change player's in-game behavior. One of such strategies is enticing players to take action through incentives akin to game achievements. We explored if this strategy could be used to influence players' proxemic behavior in the Interactive Tag Playground, an installation that enhances the traditional game of tag. We placed the ITP in an art gallery, observed hundreds of play sessions, and refined the mechanics, which consisted in projecting collectible particles around the tagger that upon collection by runners resulted only in the embellishment of their circles. We implemented the refined mechanics in a study with 48 children. The playground automatically collected the players' positions, and analyses show that runners got closer to and moved more towards taggers when using our enticing strategy. This suggests an enticing strategy can be used to influence physical in-game behavior
Dark Patterns after the GDPR: Scraping Consent Pop-ups and Demonstrating their Influence
New consent management platforms (CMPs) have been introduced to the web to
conform with the EU's General Data Protection Regulation, particularly its
requirements for consent when companies collect and process users' personal
data. This work analyses how the most prevalent CMP designs affect people's
consent choices. We scraped the designs of the five most popular CMPs on the
top 10,000 websites in the UK (n=680). We found that dark patterns and implied
consent are ubiquitous; only 11.8% meet the minimal requirements that we set
based on European law. Second, we conducted a field experiment with 40
participants to investigate how the eight most common designs affect consent
choices. We found that notification style (banner or barrier) has no effect;
removing the opt-out button from the first page increases consent by 22--23
percentage points; and providing more granular controls on the first page
decreases consent by 8--20 percentage points. This study provides an empirical
basis for the necessary regulatory action to enforce the GDPR, in particular
the possibility of focusing on the centralised, third-party CMP services as an
effective way to increase compliance.Comment: 13 pages, 3 figures. To appear in the Proceedings of CHI '20 CHI
Conference on Human Factors in Computing Systems, April 25--30, 2020,
Honolulu, HI, US
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