406 research outputs found
Automating Vehicles by Deep Reinforcement Learning using Task Separation with Hill Climbing
Within the context of autonomous driving a model-based reinforcement learning
algorithm is proposed for the design of neural network-parameterized
controllers. Classical model-based control methods, which include sampling- and
lattice-based algorithms and model predictive control, suffer from the
trade-off between model complexity and computational burden required for the
online solution of expensive optimization or search problems at every short
sampling time. To circumvent this trade-off, a 2-step procedure is motivated:
first learning of a controller during offline training based on an arbitrarily
complicated mathematical system model, before online fast feedforward
evaluation of the trained controller. The contribution of this paper is the
proposition of a simple gradient-free and model-based algorithm for deep
reinforcement learning using task separation with hill climbing (TSHC). In
particular, (i) simultaneous training on separate deterministic tasks with the
purpose of encoding many motion primitives in a neural network, and (ii) the
employment of maximally sparse rewards in combination with virtual velocity
constraints (VVCs) in setpoint proximity are advocated.Comment: 10 pages, 6 figures, 1 tabl
Mobility as a contradictory resource: Peripatetic Qur’anic students in Kano, Nigeria
Mobility is a powerful resource young people can draw on to improve their lives, but it can also entail risks. This paper explores how mobility becomes a contradictory resource for peripatetic Qur'anic students (almajirai) in Kano State in northern Nigeria. Moving to urban areas allows the young almajirai to escape difficult conditions and to access educational and income opportunities absent in their rural homes. It makes it possible for them to adopt self-conceptions as migrants in search of sacred knowledge who were once widely respected. However, economic decline has made survival in the city more difficult. Lacking the economic and cultural resources to participate in displays of status, and without social superiors to speak for them, the almajirai feel they have become fair game for those searching for scapegoats
1954: Abilene Christian College Bible Lectures - Full Text
Preface
The 1954 Abilene Christian College Lectureship was one of the best attended and most successful in the history of the school. Considerable interest was manifested in the timely theme, “Overcoming Dangerous Tendencies,” and in the two special topics, “Ways and Means of Doing Mission Work,” and “Caring For Widows and Orphans.” The reports from the mission fields were highly stimulating, and all in all, the speeches were unusually high caliber. The Panel Discussions were also on timely subjects and well presented. They received a warm response, as did also the thirty classes that were conducted each day. These classes were taught by persons expert in their particular fields, and covered a wide range of interests to the faithful, working Christian. We at Abilene Christian College predict for this book of Lectures a wide and hearty reception, and believe that its reading will issue in profit to the individual and to the church at large.
J. D. Thomas
Lectureship Directo
Road layout understanding by generative adversarial inpainting
Autonomous driving is becoming a reality, yet vehicles still need to rely on complex sensor fusion to understand the scene they act in. The ability to discern static environment and dynamic entities provides a comprehension of the road layout that poses constraints to the reasoning process about moving objects. We pursue this through a GAN-based semantic segmentation inpainting model to remove all dynamic objects from the scene and focus on understanding its static components such as streets, sidewalks and buildings. We evaluate this task on the Cityscapes dataset and on a novel synthetically generated dataset obtained with the CARLA simulator and specifically designed to quantitatively evaluate semantic segmentation inpaintings. We compare our methods with a variety of baselines working both in the RGB and segmentation domains
Fatty Acid Composition of M. Biceps Femoris of Edible Dormouse (Glis glis L.)
This study aimed to investigate the fatty acid (FA) composition of edible dormouse m. biceps
femoris in both sexes. More than 20 FA were identified in the muscle, with the 18:1cis-9 (oleic acid)
being the most abundant in both sexes, comprising more than 50% of total FA in muscle. The most
dominated FA were monounsaturated (MUFA), followed by saturated FA (SFA) and polyunsaturated
FA (PUFA), reaching 54.8%, 25.43% and 19.8% of total FA, respectively. Sums of PUFA and n-3
PUFA tended (p > 0.05) to be higher in males than in females. There were no significant differences
between sexes on the FA composition. Nevertheless, the 18:2n-6 tended to differ between sexes
(p = 0.063). Several long-chain PUFA (LC-PUFA) were detected in dormouse muscle, with the 20:4
n-6 (arachidonic acid, AA) and the 22:6 n-3 (docosahexaenoic acid, DHA) being the most abundant in
both sexes. The relatively high stearoyl-CoA desaturase (SCD) indexes and the large concentration
of 18:1cis-9 in dormouse muscle tissues might point to a low mobilization of the SCD products.
Furthermore, finding the unusual FA 20:3 D5,D11,D14, suggests feeding on leaf and wood lipids of
Coniferophytes. We demonstrated sexual size monomorphism in edible dormouse. The literature
regarding the composition of dormouse meat is scarce and no studies reported the FA composition of
muscle, thus, this work can contribute to increasing the knowledge on edible dormouse physiology
and nutritional traitsinfo:eu-repo/semantics/publishedVersio
AIBA: An AI Model for Behavior Arbitration in Autonomous Driving
Driving in dynamically changing traffic is a highly challenging task for
autonomous vehicles, especially in crowded urban roadways. The Artificial
Intelligence (AI) system of a driverless car must be able to arbitrate between
different driving strategies in order to properly plan the car's path, based on
an understandable traffic scene model. In this paper, an AI behavior
arbitration algorithm for Autonomous Driving (AD) is proposed. The method,
coined AIBA (AI Behavior Arbitration), has been developed in two stages: (i)
human driving scene description and understanding and (ii) formal modelling.
The description of the scene is achieved by mimicking a human cognition model,
while the modelling part is based on a formal representation which approximates
the human driver understanding process. The advantage of the formal
representation is that the functional safety of the system can be analytically
inferred. The performance of the algorithm has been evaluated in Virtual Test
Drive (VTD), a comprehensive traffic simulator, and in GridSim, a vehicle
kinematics engine for prototypes.Comment: 12 page
Utopianism and social change: materialism, conflict and pluralism
This article discusses criticisms that utopia and utopianism undermine social change. It outlines two types of utopia, future and current. It argues against claims that utopianism is idealist and steps aside from material and conflictual dimensions of society and so undermines change, proposing that utopias are material and conflictual and contribute to change. Against liberal and pluralist criticisms that utopianism is end-ist and totalitarian and terminates diversity and change it argues that utopianism can encompass liberal and pluralist dimensions and be dynamic rather than static. It is proposed that criticisms create false conflations and dichotomies. Critical perspectives, rather than being rejected, are answered on their own terms. Utopianism, it is argued, is part of change, materially, now and in the future
NON-INVASIVE BLOOD PRESSURE AND OTHER PHYSIOLOGICAL DATA IN CHEMICALLY IMMOBILIZED BROWN BEARS (URSUS ARCTOS)
Free-ranging brown bears (Ursus arctos) were snared and subsequently darted with a combination of xylazine-ketamine in Croatia (n = 5) or darted from a helicopter with a combination of medetomidine-tiletamine-zolazepam in Scandinavia (n = 20). Three adults and one yearling (1 year old) bear were captured in Croatia, with one adult being captured twice. The Scandinavian bears were divided into Group A (yearlings, n = 7) and Group B (subadults, n = 2 and adults, n = 11). The exertion time (time from activation of the trap or from the start of the helicopter chase to recumbency) and the induction time (time from darting to recumbency) were recorded. The rectal temperature (Tr) was measured as soon as possible after induction and then monitored at frequent intervals (varied between individuals) in immobilized bears. Blood pressure (BP) was measured with a non-invasive method (Korotkoff's technique) every 5 minutes. The heart rate (HR), respiratory rate (RR), and arterial haemoglobin oxygen saturation (SpO2) were recorded every 5 minutes. Reliability of the BP monitoring technique, trends of variation of the physiological variables, and the factors related to the capture were assessed. Both exertion and induction times were longer in Croatian bears than in Scandinavian bears. In Croatian bears, the Tr was either constant or slightly decreasing, with hyperthermia recorded in two individuals (Tr > 39.0° C). In Scandinavian bears, 17 of 20 individuals developed an initial hyperthermia. Four of five bears in Croatia and 17 of 20 bears in Scandinavia showed a decreasing trend in systolic and mean BP over time. According to the Korotkoff method, all bears were hypertensive (mean BP > 130 mmHg) with varying severity, and the systolic pressure was significantly lower in yearlings when compared to subadults and adults. Yearlings had significantly (p < 0.05) higher HR than subadults and adults, however there was no significant differences in RR, SpO2, and Tr between the age groups. All Croatian bears and 13 of 20 Scandinavian bears were moderately to severely hypoxemic (SpO2 < 90%). Further studies with simultaneous invasive and non-invasive (Korotkoff) BP monitoring techniques are required to confirm the accuracy of methods used in this study. The data presented here provides evidence of the physiological impact of different capture methods and chemical immobilization of brown bears in Croatia and Scandinavia
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