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Den främsta orsaken till en ökad växthuseffekt anses idag bero på en högre koncentrationav koldioxid i atmosfären. Sedan den industriella revolutionen harmänniskan påverkat mängden koldioxid i atmosfären genom aktiviteter så somförbränning av fossila bränslen, avskogning, förändringar i markanvändning, samtcementproduktion. För att kunna motverka framtida klimatförändringar krävs enfördjupad kunskThis thesis focuses on the development and application of efficient mathematicaltools for estimating and modelling the exchange of carbon dioxide (CO2) between the Earth and its atmosphere; here referred to as the global CO2 surface flux.There are two main approaches for estimating the CO2 flux: Processed based(bottom-up) modelling and atmospheric inversion (top-down) modelling. Thefirst part of t

Code-based cryptography is one of the main techniques enabling cryptographic primitives in a post-quantum scenario. In particular, the MDPC scheme is a basic scheme from which many other schemes have been derived. These schemes rely on iterative decoding in the decryption process and thus have a certain small probability p of having a decryption (decoding) error.In this paper we show a very fundam

Pseudo-random functions are a fundamental building block in many cryptographic applications. In certain scenarios, a weaker notion (where security is restricted to uniformly random input), but more computationally efficient, called weak pseudo-random functions, is sufficient. In this work, we present new differential attacks on the main binary weak pseudo-random function constructions, namely the

Recently there has been an increase in the number of available autonomous vehicle (AV) models. To evaluate and compare the safety of the various models the AVs need to be tested in several diverse safety-critical scenarios. We propose the Adversarial Test Case Generator (ATCG) that differently from previous test case generators allows for the generation of realistic collision scenarios with varied

In this paper, we present the first chosen-ciphertext (CC) cache-timing attacks on the reference implementation of HQC. We build a cache-timing based distinguisher for implementing a plaintext-checking (PC) oracle. The PC oracle uses side-channel information to check if a given ciphertext decrypts to a given message. This is done by identifying a vulnerability during the generating process of two

In this paper, we show that a software implementation of IND-CCA-secure Saber key encapsulation mechanism protected by first-order masking and shuffling can be broken by deep learning-based power analysis. Using an ensemble of deep neural networks trained at the profiling stage, we can recover the session key and the secret key from 257 × N and 24 × 257 × N traces, respectively, where N is the num

We consider a perturbation problem for embedded eigenvalues of a self-adjoint differential operator in L2(R;Rn). In particular, we study the set of all small perturbations in an appropriate Banach space for which the embedded eigenvalue remains embedded in the continuous spectrum. We show that this set of small perturbations forms a smooth manifold and we specify its co-dimension. Our methods invo

Connected and automated vehicles (CAVs) will be a key component of future cooperative intelligent transportation systems (C-ITS). Since the adoption of C-ITS is not foreseen to happen instantly, not all of its elements are going to be connected at the early deployment stages. We consider a scenario where vehicles approaching a traffic light are connected to each other, but the traffic light itself

Given a sensor network, TDOA self-calibration aims at simultaneously estimating the positions of receivers and transmitters, and transmitters time offsets. This can be formulated as a system of polynomial equations. Due to the elevated number of unknowns and the nonlinearity of the problem, obtaining an accurate solution efficiently is nontrivial. Previous work has shown that iterative algorithms

Monocular depth estimation is a highly challenging problem that is often addressed with deep neural networks. While these use recognition of high level image features to predict reasonably looking depth maps,the result often has poor metric accuracy. Moreover,the standard feed forward architecture does not allow modification of the prediction based on cues other than the image.In this paper we rel

Open-Source Software (OSS) is increasingly common in industry software and enables developers to build better applications, at a higher pace, and with better security. These advantages also come with the cost of including vulnerabilities through these third-party libraries. The largest publicly available database of easily machine-readable vulnerabilities is the National Vulnerability Database (NV

Correlation attacks apply mainly to stream ciphers and can be considered as an extension of the idea of distinguishing attacks to collect information on secret key bits. The original correlation attack was proposed by Siegenthaler on nonlinear combination generators. In a nonlinear combination generator, the keystream is generated as the output of a Boolean function with inputs being sequences fro

In this thesis, we address three main security problems related to cryptography andcloud storage. To tackle the challenge posed by a quantum computer, we needencryption that is resistant to quantum computers. This category of cryptographyis called post-quantum cryptography. In the first paper, we solve a challengein one of the lattice-based cryptographic protocols called Nth-degree Truncatedpolyno

For a generalized (or non-central) camera model, the minimal problem for two views of six points has efficient solvers. However, minimal problems of three views with four points and three views of six lines have not yet been explored and solved, despite the efforts from the computer vision community. This paper develops the formulations of these two minimal problems and shows how state-of-the-art

Intensity Analysis (IA) of land use and land cover change (LULCC) is important to support policy and practice. We applied IA to analyse LULCC in Sironko catchment, Uganda. Results show that agricultural land, forest, and wetland reduced by 8%; 32%; and 20% between 1986-2000. Between 2000-2016, forest, wetland, and built-up areas increased by 84%, 5%, and 57%. Active gainers between 1986-2000 were

With the inclusion of external software components in their software, vendors also need to identify and evaluate vulnerabilities in the components they use. A growing number of external components makes this process more time-consuming, as vendors need to evaluate the severity and applicability of published vulnerabilities. The CVSS score is used to rank the severity of a vulnerability, but in its

User generated content (UGC) makes up a significant portion of Internet traffic. As opposed to other content, UGC has so far been left outside over-the-top providing network operators content distribution networks (telco-CDN) due to the difficulty in determining optimised placement of such content. The side effect of this is that UGC content is not placed close to end users and therefore occupy un

Organizations and individuals maintain and use an ever increasing amount of computer systems, either deployed locally, or in the cloud.These systems often store and handle vast amounts of data, some of which is sensitive and should be kept private.Regardless of where the data is located, there is a need to prevent data from falling into the wrong hands.To this end, this dissertation presents contr