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In this paper we consider a mobile platform performing partial hand-eye calibration and Simultaneous Localisation and Mapping (SLAM) using images of the floor along with the assumptions of planar motion and constant internal camera parameters. The method used is based on a direct parametrisation of the camera motion, combined with an iterative scheme for determining the motion parameters from inte
Description: Python® is a free open-source language and environment that has great potential in scientific computing. Computing with Python presents the programming language in close connection wit mathematical applications. The approach of the book is concept based rather than a systematic introduction to the language. It is written for a mathematical readership and is aimed at students with a ma
During the last decades, image analysis has become an important tool in various applications. The increase in computer power has led to that more advances algorithms can be developed. In this thesis image analysis has been used in three different applications; quality control of asphalt, cancer detection in histopathological images and traffic surveillance. In the first part of the thesis image a
In this paper, we study minimal problems related to dual microphone rig self-calibration using TOA measurements from sound sources with unknown positions. We consider the problems with varying setups as (i) if the internal distances between the microphone nodes are known a priori or not. (ii) if the microphone rigs lies in an affine space with different dimension than the sound sources. Solving th
Global fire-vegetation models are widely used to assess impacts of environmental change on fire regimes and the carbon cycle and to infer relationships between climate, land use and fire. However, differences in model structure and parameterizations, in both the vegetation and fire components of these models, could influence overall model performance, and to date there has been limited evaluation
A growing number of connected IoT devices makesit more and more difficult for the network to provide the desiredreliability in any deployment scenario. The advent of NB-IoTtechnology opens new possibilities for low-power long-range IoTapplications. However, the design of the standard introduces highbattery drainage in the situations when the radio conditionsbetween the UE and the eNB are poor. Dev
Discontinuous Reception (DRX) has been included in 4G-LTE as the main power saving mechanism for User Equipment (UE). However, the existing 3-state DRX model is not sufficient for new use cases introduced by 4G and 5G. For example, the device discovery process in Device to Device (D2D) communication has a significant impact on delay and power consumption, but the existing conventional 3-state DRX
In this paper we study resilience of TDMA-based wireless sensor networks to node failures. We investigate exploiting mutlicast routing for providing redundancy in the number of gateways used by data streams, so as to protect them against gateway failures. To do this, we develop an optimization model aiming at packet traffic throughput maximization composed of three mixed-integer programming proble
Concerns about food security under climate change motivate efforts to better understand future changes in crop yields. Process-based crop models, which represent plant physiological and soil processes, are necessary tools for this purpose since they allow representing future climate and management conditions not sampled in the historical record and new locations to which cultivation may shift. How
Low rank structures are present in many applications of computer vision and machine learning. A popular approach consists of explicitly parameterising the set or matrices with sought rank, leading to a bilinear factorisation, reducing the problem to find the bilinear factors. While such an approach can be efficiently implemented using second-order methods, such as Levenberg-Marquardt (LM) or Varia
We investigate the trade-off between energy usage and (packet) throughput in wireless mesh networks performing machine-to-machine communication. For this we provide a novel mixed-integer programming formulation to maximise the throughput while maintaining minimal energy usage, together with an effective price-and-branch solution algorithm based on column generation. The resulting optimisation mode
Open Source Security and Dependency Vulnerability Management (DVM) has become a more vital part of the software security stack in recent years as modern software tend to be more dependent on open source libraries. The largest open source of vulnerabilities is the National Vulnerability Database (NVD), which supplies developers with machine-readable vulnerabilities. However, sometimes Common Vulner
Estimating receiver and sender positions is often solved using a stratified, two-tiered approach. In the first step the problem is converted to a low-rank matrix estimation problem. The second step can be seen as an affine upgrade. This affine upgrade is the focus of this paper. In the paper new efficient algorithms for solving for the upgrade parameters using minimal data are presented. It is als
We study a scenario where a monitor is interested in the freshest possible update from a remote sensor. The monitor also seeks to minimize the number of updates that exceed a certain freshness threshold, beyond which, the information is deemed to be too old. Previous work has presented results for First Come First Served (FCFS) systems. However, it has been shown that Last Come First Served (LCFS)
In this paper we address the energy consumption of the Constraint Application Protocol (CoAP) and the Message Queue Telemetry Transport (MQTT) protocol and compare their overhead. We also pay attention to the use case of security in IoT and analyze the energy consumption when using TLS/DTLS for the two protocols. In our experiments we use ESP32 with libcoap, MQTT, and mbed TLS libraries and conduc
In this thesis, we investigate and develop new methods for efficient and functional use of resources in edge networks. Setting this work aside from previous work, we study User Generated Content (UGC) such as social media information and data generated in the new emerging Internet of Things systems. We present efficient solutions for placing such content and managing which network resources should
Intellectual property rights (IPRs) represent a key concern for researchers and industry in basically all (high-tech) sectors. IPRs regularly figure prominently in scientific journals and at scientific conferences and lead to dedicated workshops to increase the awareness and “IPR savviness” of scientists. In 2015, Biotechnology Journal published a report from an expert meeting on “Synthetic Biolog
In this paper, robust detection, tracking and geometry estimation methods are developed and combined into a system for estimating time-difference estimates, microphone localization and sound source movement. No assumptions on the 3D locations of the microphones and sound sources are made. The system is capable of tracking continuously moving sound sources in an reverberant environment. The multi-p
This survey overviews the potential use of cryptographic primitives in the fifth-generation mobile communications system (aka 5G) and beyond. It discusses the new security challenges that come with 5G and presents the upcoming security architecture. It shows the use of current cryptographic algorithms and discusses new algorithms or modifications of existing ones, that can be relevant. It also dis
Changes in forest cover have a strong effect on climate through the alteration of surface biogeophysical and biogeochemical properties that affect energy, water and carbon exchange with the atmosphere. To quantify biogeophysical and biogeochemical effects of deforestation in a consistent setup, nine Earth system models (ESMs) carried out an idealized experiment in the framework of the Coupled Mode
