Sequential Attacks on Kalman Filter-based Forward Collision Warning Systems

Kalman Filter (KF) is widely used in various domains to perform sequential learning or variable estimation. In the context of autonomous vehicles, KF constitutes the core component of many Advanced Driver Assistance Systems (ADAS), such as Forward Collision Warning (FCW). It tracks the states (distance, velocity etc.) of relevant traffic objects based on sensor measurements. The tracking output of KF is often fed into downstream logic to produce alerts, which will then be used by human drivers to make driving decisions in near-collision scenarios. In this paper, we study adversarial attacks on KF as part of the more complex machine-human hybrid system of Forward Collision Warning. Our attack goal is to negatively affect human braking decisions by causing KF to output incorrect state estimations that lead to false or delayed alerts. We accomplish this by sequentially manipulating measure ments fed into the KF, and propose a novel Model Predictive Control (MPC) approach to compute the optimal manipulation. Via experiments conducted in a simulated driving environment, we show that the attacker is able to successfully change FCW alert signals through planned manipulation over measurements prior to the desired target time. These results demonstrate that our attack can stealthily mislead a distracted human driver and cause vehicle collisions.Comment: Accepted by AAAI2

Utilising a simulation platform to understand the effect of domain model assumptions

© The Author(s) 2014. This article is published with open access at Springerlink.com. Open Access This article is distributed under the terms of the Creative Commons Attribution License which permits any use, distribution, and reproduction in any medium, provided the original author(s) and the source are credited.Computational and mathematical modelling approaches are increasingly being adopted in attempts to further our understanding of complex biological systems. This approach can be subjected to strong criticism as substantial aspects of the biological system being captured are not currently known, meaning assumptions need to be made that could have a critical impact on simulation response. We have utilised the CoSMoS process in the development of an agent-based simulation of the formation of Peyer's patches (PP), gut-associated lymphoid organs that have a key role in the initiation of adaptive immune responses to infection. Although the use of genetic tools, imaging technologies and ex vivo culture systems has provided significant insight into the cellular components and associated pathways involved in PP development, interesting questions remain that cannot be addressed using these approaches, and as such well justified assumptions have been introduced into our model to counter this. Here we focus not on the development of the model itself, but instead demonstrate how the resultant simulation can be used to assess how these assumptions impact the simulation response. For example, we consider the impact of our assumption that the migration rate of lymphoid tissue cells into the gut remains constant throughout PP development. We demonstrate that an analysis of the assumptions made in the construction of the domain model may either increase confidence in the model as a representation of the biological system it captures, or may suggest areas where further biological experimentation is required.This work was funded by the Wellcome Trust [ref:097829] through the Centre for Chronic Diseases and Disorders (C2D2) at the University of York. Paul Andrews is funded by EPSRC grant EP/I005943/1 “Resilient Futures.” Henrique Veiga-Fernandes is funded by Fundação para a Ciência e Tecnologia (PTDC/SAU-MII/100016/2008), Portugal, European Molecular Biology Organisation (Project 1648) and European Research Council (Project 207057). Jon Timmis is part funded by the Royal Society and the Royal Academy of Engineering. Funding for Mark Coles comes from grants from the Human Frontiers Science Program (RGP0006/2009) and the Medical Research Council (G0601156).info:eu-repo/semantics/publishedVersio

The association of alcohol dependence and consumption during adolescence with depression in young adulthood, in England: a prospective cohort study

BACKGROUND: The role of alcohol use in the development of depression is unclear. We aimed to investigate whether alcohol dependence, but not high frequency or quantity of consumption, during adolescence increased the risk of depression in young adulthood. METHODS: In this prospective cohort study, we included adolescents who were born to women recruited to the Avon Longitudinal Study of Parents and Children in Avon, UK, with delivery dates between April 1, 1991, and Dec 31, 1992. Alcohol dependence and consumption were measured at about age 16 years, 18 years, 19 years, 21 years, and 23 years using the self-reported Alcohol Use Disorders Identification Test, and at about age 18 years, 21 years, and 23 years using items corresponding to DSM-IV symptoms. The primary outcome was depression at age 24 years, assessed using the Clinical Interview Schedule Revised. Analyses were probit regressions between growth factors for alcohol dependence and consumption and depression, before and after adjustments for confounders: sex, housing tenure, maternal education, maternal depressive symptoms, parents' alcohol use, conduct problems at age 4 years, being bullied from age 12-16 years, and frequency of smoking cigarettes or cannabis. Adolescents were included in analyses if they had data from at least one timepoint for alcohol use and confounders. FINDINGS: We included 3902 adolescents (2264 [58·0%] female; 1638 [42·0%] male) in our analysis, and 3727 (96·7%) of 3853 participants with data on ethnicity were White. After adjustments, we found a positive association between alcohol dependence at 18 years of age (latent intercept) and depression at 24 years of age (probit coefficient 0·13 [95% CI 0·02 to 0·25]; p=0·019), but no association between rate of change (linear slope) and depression (0·10 [-0·82 to 1·01]; p=0·84). There was no evidence of an association between alcohol consumption and depression (latent intercept probit coefficient -0·01 [-0·06 to 0·03]; p=0·60; linear slope 0·01 [-0·40 to 0·42]; p=0·96) after adjustments. INTERPRETATION: Psychosocial or behavioural interventions that reduce the risk of alcohol dependence during adolescence could contribute to preventing depression in young adulthood. FUNDING: UK Medical Research Council and Alcohol Research UK (grant number MR/L022206/1)

Identification and measurement of tropical tuna species in purse seiner catches using computer vision and deep learning

Fishery monitoring programs are essential for effective management of marine resources, as they provide scientists and managers with the necessary data for both the preparation of scientific advice and fisheries control and surveillance. The monitoring is generally done by human observers, both in port and onboard, with a high cost involved. Consequently, some Regional Fisheries Management Organizations (RFMO) are opting for electronic monitoring (EM) as an alternative or complement to human observers in certain fisheries. This is the case of the tropical tuna purse seine fishery operating in the Indian and Atlantic oceans, which started an EM program on a voluntary basis in 2017. However, even when the monitoring is conducted though EM, the image analysis is a tedious task manually performed by experts. In this paper, we propose a cost-effective methodology for the automatic processing of the images already being collected by cameras onboard tropical tuna purse seiners. Firstly, the images are preprocessed to homogenize them across all vessels and facilitate subsequent steps. Secondly, the fish are individually segmented using a deep neural network (Mask R-CNN). Then, all segments are passed through other deep neural network (ResNet50V2) to classify them by species and estimate their size distribution. For the classification of fish, we achieved an accuracy for all species of over 70%, i.e., about 3 out of 4 individuals are correctly classified to their corresponding species. The size distribution estimates are aligned with official port measurements but calculated using a larger number of individuals. Finally, we also propose improvements to the current image capture systems which can facilitate the work of the proposed automation methodology.This project is funded by the Basque Government, and the Spanish fisheries ministry through the EU next Generation funds. Jose A. Fernandes'work has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreements No 869342 (SusTunTech). This work is supported in part by the University of the Basque Country UPV/EHU grant GIU19/027. We want to thank the expert analysts who helped to annotate images with incredible effort: Manuel Santos and Inigo Krug. We also like to extend our gratitude to Marine Instruments for providing the necessary equipment tocollect the data. This paper is contribution no 1080 from AZTI, Marine Research, Basque Research and Technology Alliance (BRTA)

Photodynamic therapy and diagnosis: Principles and comparative aspects.

Photodynamic therapy (PDT) is an evolving method of treating superficial tumours that is non-invasive and carries minimal risk of toxicity. It combines tumour-selective photosensitiser dyes, tissue oxygen and targeted illumination to generate cytotoxic reactive oxygen species (ROS) within the tumour. In addition to directly acting on tumour cells, PDT damages and restricts tumour microvasculature, and causes a local inflammatory response that stimulates an immune response against the tumour. Unlike surgery or radiotherapy, the surrounding extracellular matrix is unaffected by PDT; thus, tissue healing is excellent and PDT seldom causes scars. This, combined with the ease of light application, has made PDT a popular treatment for cancers and pre-cancerous conditions in human beings. Moreover, because photosensitiser dyes are fluorescent and selectively accumulate in tumour tissues, they can additionally be used to visualise and discriminate tumour from normal tissues, thereby improving the accuracy of tumour surgery. In veterinary practice, PDT has been used successfully for treatment of superficial squamous cell carcinomas of the feline nasal planum; urinary tract, urinary bladder and prostate neoplasia in dogs; and equine sarcoids. The purpose of this article is to provide a comparative review of the current literature on PDT in human and veterinary medicine, and to establish a basis for future development of PDT in veterinary medicine

Editorial: diversity of marine meiofauna on the coast of Brazil

After a first bout of primarily taxonomical effort, meiofauna studies in Brazilian waters remained virtually neglected until the 1990s. At the end of the last century, taxonomical and ecological studies on meiofauna taxa were again published regularly, especially for Nematoda and Copepoda. In this issue, 18 new species are described and ten species are redescribed from seven Phyla. The five ecological articles cover the spatial distribution of forams and amoeba in a lagunar system, the meiofauna associated with biogenic structures, the relationship between nematodes and granulometry, and the response of sandy-beach meiofauna to a natural, short-term pulse of diatoms. All these contributions show the potential of the Brazilian coast for revealing new species and testing small to large-scale hypotheses about ecological processes

Hubble Space Telescope WFPC-2 Imaging of Cassiopeia A

The young SNR Cassiopeia A was imaged with WFPC-2 through four filters selected to capture the complete velocity range of the remnant's main shell in several important emission lines. Primary lines detected were [O III] 4959,5007, [N II] 6583, [S II] 6716,6731 + [O II] 7319,7330 + [O I] 6300,6364, and [S III] 9069,9532. About 3/4th of the remnant's main shell was imaged in all four filters. Considerable detail is observed in the reverse-shocked ejecta with typical knot scale lengths of 0.2"-0.4" (1 - 2 x 10^16 cm). Both bright and faint emission features appear highly clumped. Large differences in [S III] and [O III] line intensities indicating chemical abundance differences are also seen, particularly in knots located along the bright northern limb and near the base of the northeast jet. A line of curved overlapping filament in the remnant's northwestern rim appears to mark the location of the remnant's reverse shock front in this region. Finger-like ejecta structures elsewhere suggest cases where the reverse shock front is encountering the remnant's clumped ejecta. Narrow-band [N II] images of the remnant's circumstellar knots ("QSFs") reveal them to be 0.1"-0.6" thick knots and filaments, often with diffuse edges facing away from the center of expansion. Three color composite images of the whole remnant and certain sections along with individual filter enlargements of selected regions of the bright optical shell are presented and discussed.Comment: 26 pages, 12 figures Accepted to the Astronomical Journa