Detektering, målföljning och identifiering med robotsystem 90

The objective was to clarify whether and how it is possible to detect, track and identify with an EO/IR (electro optical/infrared) sensor. Moreover, the sight of robotic system 90 was tested in order to clarify the possibilities of using it as a sensor. The sight has a field of view of 3x4° with the TV camera and 4x6° with the IRV camera. Therefore, the project focused on a moving sensor, in order to be able to scan a larger area. By background subtraction it´s possible to detect changes, i.e., movements. The background must move with the sight and therefore requires measurements of the sight direction to be accurate. Detection was made possible by noise reduction of the measured values using a Kalman filter. The maximum scan rate of the sight was 10.8°² /s. The sight can thus not be used as a sensor because the scanning speed is judged to be too low. Kalman filters may also be used to filter the detections and for a short time predict the target path. With a scaling matrix, error in the velocity vector was reduced when the target was not manoeuvring and the target movement could be predicted over time. However, it led to delays when the target manoeuvred, resulting in poor accuracy of the target position. The video color from the sight is in grayscale, which means that the color couldn´t be used to identify aircraft. The aircraft is dark with the TV camera and bright with the IRV camera. What was left then was to identify the type of aircraft by analysing the shape. An existing method for identification by shape analysis is HOG (Histogram of Oriented Gradients). A large amount of training data was required for the support vector machine to handle the differences in shape depending on the sensor viewing angle, the aircraft´s rotation and the relatively small pictures. However, the reliability of the method was still not high enough. Two custom methods were therefore tested in order to try to identify targets by shape analysis. In the first method a 3D model of an airplane was built. The identification would be done by rotating and projecting the model to a two-dimensional image which was compared with the image of the target. Finding the best three-dimensional rotation is a problem which can be solved only by testing all solutions. Therefore, it takes too long to identify with this method. The second method aims to analyse the shape by rotating the two-dimensional image so that the nose is pointing along the x-axis of a two-dimensional coordinate system. Wings were then analysed by analysing the values on the y-coordinates relative to the x-coordinates. Maxima, minima and the gradients were analysed in order to place the wings, estimate their relative size to each other and the shape of the aircraft. Method two may be used to increase the reliability of the identification of the aircraft. An autonomous combat system requires the identification to be very reliable, thus requiring the use of an optical zoom to enlarge the images. More parameters such as position, speed and size should also be analysed when identifying the target

Online Tribes and Digital Authority:What Can Social Theory Bring to Digital Archaeology?

From early discussions of the disruptive potential of computer technologies for archaeological applications, to the present era of digital archaeology as the technical underpinning of modern archaeological practice, we have continued to debate the potential impacts of digital communication and digital capture and storage on our knowledge, profession and communications. The increased use of digital tools and methods for archaeological research and dissemination, as well as what Roosevelt (2015) has referred to as the shift to the digital paradigm within archaeological practice, leads us to suggest that the impact of this paradigm shift requires careful and critical examination. This article will examine the edges of the disciplines of archaeology and sociology, where we aim to advance our understanding of the relationship between digital technologies and archaeological knowledge from a uniquely social perspective, using the theoretical approaches of both classic and modern sociologists. The application of this lens of sociology to digital archaeology equips us to understand how archaeology and archaeological practice is situated in a social world, which is especially relevant in the Global West, where digital technology is ubiquitous. Through a critical consideration of the complexity of use of digital technologies within digital archaeology, we can begin to shift our focus away from the character and method of tools and workflow, to the background of intellectual power and influence

Extensiones del marco traslocal en protestas en red: el caso del hashtag #idlenomore

The aim of the present study was to examine how locally situated social movements can use social media to deploy translocally networked forms of protests. The study looks at the Canadian Idle No More movement, an indigenous and environmental grassroots initiative that emerged around the end of 2012 and the beginning of 2013 as a reaction to previous neglect of indigenous groups and to the omnibus bill proposal C-45 (which threatened both the partial sovereignty of indigenous territories and the Canadian environment). Focusing on the -decentralized and heterogeneous- movement’s Twitter use in general, and the employment of the hashtag #idlenomore in particular, the study examines to which extent and how Twitter may be a means for establishing bonds between geographically dispersed social movements.El objetivo del presente estudio es examinar cómo movimientos sociales locales pueden usar formulas de protesta traslocal en red. El estudio trata sobre el movimiento canadiense “Idle No More”, una iniciativa medioambiental indígena de base que emerge a finales del 2012 y principios de 2013 como reacción a la marginación de los grupos indígenas y a la propuesta de ley “omnibus” C-45 (que amenazaba tanto la soberanía de los territorios indígenas como el medioambiente canadiense). En relación con el habitualmente descentralizado y heterogéneo uso de Twitter , y en particular, con la forma de emplear el hashtag #idlenomore, el estudio examina en qué medida y cómo Twiter puede ser una forma de establecer lazos entre movimientos sociales dispersos geográficamente

Refined SRP Stack Memory Analysis by Exploiting Critical Sections for Shared Resources

International audienceIn this paper we refine previous results on stack memory analysis for SRP based systems. For a task J we associate the section of code in between a resource request and release of R to a sub-task J R . If J R is implemented as a function, the stack usage of J R can be accounted for locally (and not part of the initial allocation for J as done in previously published work.

Decay of extremals of Morrey's inequality

We study the decay (at infinity) of extremals of Morrey's inequality in $\mathbb{R}^n$. These are functions satisfying $$\displaystyle \sup_{x\neq y}\frac{|u(x)-u(y)|}{|x-y|^{1-\frac{n}{p}}}= C(p,n)\|\nabla u\|_{L^p(\mathbb{R}^n)} ,$$ where $p>n$ and $C(p,n)$ is the optimal constant in Morrey's inequality. We prove that if $n \geq 2$ then any extremal has a power decay of order $\beta$ for any $$ \beta<-\frac13+\frac{2}{3(p-1)}+\sqrt{\left(-\frac13+\frac{2}{3(p-1)}\right)^2+\frac13}. $

Modelling the genetic aetiology of complex disease: human-mouse conservation of noncoding features and disease-associated loci

Understanding the genetic aetiology of loci associated with a disease is crucial for developing preventative measures and effective treatments. Mouse models are used extensively to understand human pathobiology and mechanistic functions of disease-associated loci. However, the utility of mouse models is limited in part by evolutionary divergence in transcription regulation for pathways of interest. Here, we summarize the alignment of genomic (exonic and multi-cell regulatory) annotations alongside Mendelian and complex disease-associated variant sites between humans and mice. Our results highlight the importance of understanding evolutionary divergence in transcription regulation when interpreting functional studies using mice as models for human disease variants

An interview based study of pioneering experiences in teaching and learning Complex Systems in Higher Education

Due to the interdisciplinary nature of complex systems as a field, students studying complex systems at University level have diverse disciplinary backgrounds. This brings challenges (e.g. wide range of computer programming skills) but also opportunities (e.g. facilitating interdisciplinary interactions and projects) for the classroom. However, there is little published regarding how these challenges and opportunities are handled in teaching and learning Complex Systems as an explicit subject in higher education, and how this differs in comparison to other subject areas. We seek to explore these particular challenges and opportunities via an interview-based study of pioneering teachers and learners (conducted amongst the authors) regarding their experiences. We compare and contrast those experiences, and analyse them with respect to the educational literature. Our discussions explored: approaches to curriculum design, how theories/models/frameworks of teaching and learning informed decisions and experience, how diversity in student backgrounds was addressed, and assessment task design. We found a striking level of commonality in the issues expressed as well as the strategies to handle them, for example a significant focus on problem-based learning, and the use of major student-led creative projects for both achieving and assessing learning outcomes.Comment: 16 page

Numerical analysis of a reinforcement learning model with the dynamic aspiration level in the iterated Prisoner's Dilemma

Humans and other animals can adapt their social behavior in response to environmental cues including the feedback obtained through experience. Nevertheless, the effects of the experience-based learning of players in evolution and maintenance of cooperation in social dilemma games remain relatively unclear. Some previous literature showed that mutual cooperation of learning players is difficult or requires a sophisticated learning model. In the context of the iterated Prisoner's Dilemma, we numerically examine the performance of a reinforcement learning model. Our model modifies those of Karandikar et al. (1998), Posch et al. (1999), and Macy and Flache (2002) in which players satisfice if the obtained payoff is larger than a dynamic threshold. We show that players obeying the modified learning mutually cooperate with high probability if the dynamics of threshold is not too fast and the association between the reinforcement signal and the action in the next round is sufficiently strong. The learning players also perform efficiently against the reactive strategy. In evolutionary dynamics, they can invade a population of players adopting simpler but competitive strategies. Our version of the reinforcement learning model does not complicate the previous model and is sufficiently simple yet flexible. It may serve to explore the relationships between learning and evolution in social dilemma situations.Comment: 7 figure

Infectious Diseases, Climate Influences, and Nonstationarity

Cazelles and Hales discuss a new study that uses a range of mathematical tools to illustrate a clear relationship between climatic variables and the dynamics of cutaneous leishmaniasis