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http://orbit.dtu.dk/en/publishers/technical-university-of-denmark-dtu(f7c040ab-194a-4da4-b458-670da24b2a08)/search/publications.html?page=1
RSS FeedFri, 16 Sep 2016 09:06:33 GMT2016-09-16T09:06:33ZDesign and analysis of cryptographic algorithms
http://orbit.dtu.dk/en/publications/design-and-analysis-of-cryptographic-algorithms(c3ac3f18-2898-476c-957b-59b83ee77d0d).html
<div style='font-size: 9px;'><div class="rendering rendering_publication rendering_publication_short rendering_bookanthology rendering_short rendering_bookanthology_short"><h2 class="title"><a rel="BookAnthology" href="http://orbit.dtu.dk/en/publications/design-and-analysis-of-cryptographic-algorithms(c3ac3f18-2898-476c-957b-59b83ee77d0d).html" class="link"><span>Design and analysis of cryptographic algorithms</span></a></h2><a rel="Person" href="http://orbit.dtu.dk/en/persons/stefan-koelbl(45ab0201-3844-404a-bbff-1ba4b392a953).html" class="link person"><span>Kölbl, S.</span></a>, <a rel="Person" href="http://orbit.dtu.dk/en/persons/christian-rechberger(2b326705-e9ce-4f75-8852-a312f3ed2260).html" class="link person"><span>Rechberger, C.</span></a> & <a rel="Person" href="http://orbit.dtu.dk/en/persons/lars-ramkilde-knudsen(a62b8acd-d07f-4943-a467-85af0eb5efe0).html" class="link person"><span>Knudsen, L. R.</span></a> <span class="date">2016</span> Kgs. Lyngby: <a rel="Publisher" href="http://orbit.dtu.dk/en/publishers/technical-university-of-denmark-dtu(f7c040ab-194a-4da4-b458-670da24b2a08).html" class="link"><span>Technical University of Denmark (DTU)</span></a>. <span class="numberofpages">257 p.</span> (DTU Compute PHD-2016; No. 434).<p class="type"><span class="type_family">Publication<span class="type_family_sep">: </span></span><span class="type_classification_parent">Research<span class="type_parent_sep"> › </span></span><span class="type_classification">Ph.D. thesis – Annual report year: 2016</span></p></div><div class="rendering rendering_publication rendering_publication_detailsportal rendering_bookanthology rendering_detailsportal rendering_bookanthology_detailsportal"><div class="abstract"><div class="textblock">In today’s world computers are ubiquitous. They can be found in virtually any industry and most households own at least one personal computer or have a mobile phone. Apart from these fairly large and complex devices, we also see computers on a much smaller scale appear in everyday objects in the form of micro-controllers and RFID chips.<br /><br />What truly transformed our society are large scale networks, like the Internet or mobile telephone networks, which can link billions of devices. Our ways of communicating and conducting business have severely changed over the last decades due to this development. However, most of this communication happens over inherently insecure channels requiring methods to protect our communication. A further issue is the vast amount of data generated, which raises serious privacy concerns.<br /><br />Cryptography provides the key components for protecting our communication. From securing our passwords and personal data to protecting mobile communication from eavesdroppers and our electronic bank transactions from manipulation. These applications would be impossible without cryptography. <br /><br />The main topic of this thesis is the design and security analysis of the most fundamental algorithms used in cryptography, namely block ciphers and cryptographic hash functions. These algorithms are the building blocks for a vast amount of applications and play a vital role in providing both confidentiality and integrity for our communication. <br /><br />This work is organized in two parts. First, an introduction to block ciphers and cryptographic hash functions is given to provide an overview over the state-of-the-art, the terminology, and how we can evaluate the security of an algorithm. The second part is a collection of scientific publications that have been written during the PhD studies and published. <br /><br />In the first publication we analyze the security of cryptographic hash functions based on the AES and demonstrate practical attacks on reduced-round versions of these algorithms. The second publication provides cryptanalysis of the lightweight block cipher SIMON in particular how resistant this type of block ciphers are against differential and linear cryptanalyis. In the fourth publication we present a short-input hash function utilizing AES-specific instructions on modern CPUs in order to improve the performance of hashbased signature schemes. The last publication deals with the design of the tweakable lightweight block cipher Skinny which provides strong security bounds against differential and linear attacks while also competing with the performance of SIMON.</div></div><div class="phddissertation"><table class="properties"><tbody><tr class="language"><th>Original language</th><td>English</td></tr></tbody></table><table class="properties"><tbody><tr><th>Place of Publication</th><td>Kgs. Lyngby</td></tr><tr><th>Publisher</th><td><a rel="Publisher" href="http://orbit.dtu.dk/en/publishers/technical-university-of-denmark-dtu(f7c040ab-194a-4da4-b458-670da24b2a08).html" class="link"><span>Technical University of Denmark (DTU)</span></a></td></tr><tr><th>Number of pages</th><td>257</td></tr><tr class="status"><th>State</th><td><span class="prefix">Submitted - </span><span class="date">2016</span></td></tr></tbody></table></div> <table class="properties"><tbody><tr><th>Name</th><td>DTU Compute PHD-2016</td></tr><tr><th>Number</th><td>434</td></tr><tr><th>ISSN (print)</th><td>0909-3192</td></tr></tbody></table></div></div>Thu, 31 Dec 2015 23:00:00 GMThttp://orbit.dtu.dk/en/publications/design-and-analysis-of-cryptographic-algorithms(c3ac3f18-2898-476c-957b-59b83ee77d0d).html2015-12-31T23:00:00ZAn Investigation of Methods for CT Synthesis in MR-only Radiotherapy
http://orbit.dtu.dk/en/publications/an-investigation-of-methods-for-ct-synthesis-in-mronly-radiotherapy(9a1a2093-e7f9-4415-8233-dad1ba5460ff).html
<div style='font-size: 9px;'><div class="rendering rendering_publication rendering_publication_short rendering_bookanthology rendering_short rendering_bookanthology_short"><h2 class="title"><a rel="BookAnthology" href="http://orbit.dtu.dk/en/publications/an-investigation-of-methods-for-ct-synthesis-in-mronly-radiotherapy(9a1a2093-e7f9-4415-8233-dad1ba5460ff).html" class="link"><span>An Investigation of Methods for CT Synthesis in MR-only Radiotherapy</span></a></h2><a rel="Person" href="http://orbit.dtu.dk/en/persons/daniel-andreasen(d45d8ed5-c7b3-44eb-ac2e-1c3ecd43f8f2).html" class="link person"><span>Andreasen, D.</span></a> & <a rel="Person" href="http://orbit.dtu.dk/en/persons/koen-van-leemput(265767e4-0af5-4996-acf2-288bf3d27030).html" class="link person"><span>Van Leemput, K.</span></a> <span class="date">2016</span> Kgs. Lyngby: <a rel="Publisher" href="http://orbit.dtu.dk/en/publishers/technical-university-of-denmark-dtu(f7c040ab-194a-4da4-b458-670da24b2a08).html" class="link"><span>Technical University of Denmark (DTU)</span></a>. <span class="numberofpages">72 p.</span> (DTU Compute PHD-2016; No. 428).<p class="type"><span class="type_family">Publication<span class="type_family_sep">: </span></span><span class="type_classification_parent">Research<span class="type_parent_sep"> › </span></span><span class="type_classification">Ph.D. thesis – Annual report year: 2016</span></p></div><div class="rendering rendering_publication rendering_publication_detailsportal rendering_bookanthology rendering_detailsportal rendering_bookanthology_detailsportal"><div class="abstract"><div class="textblock">In recent years, the interest in using magnetic resonance (MR) imaging in radiotherapy (RT) has increased. This is because MR has a superior soft tissue contrast compared to computed tomography (CT), which makes it a better modality for delineating the target volume (tumor) and possible organs at risk (OARs). In an MR/CT work-flow, independent MR and CT scans are acquired. The target and possible OARs are delineated on the MR and then transferred to CT by aligning the data using a registration. This introduces the risk of systematic registration errors especially in non-rigid body structures, the consequence being a systematic miss of target or increased dose to healthy tissue. <br /><br />Radiotherapy based on MR as the only modality removes this uncertainty and simplifies the clinical work-flow. However, the information on electron density which is usually contained in the CT must now be derived from the MR. A way to achieve this is to computationally estimate a so-called synthetic CT (sCT) from the MR data, which can then act as a substitute for the CT. This is a challenging task, since no unique relationship between MR and electron density exists.<br /><br />The goal of this thesis is to develop and investigate the right combination of MR acquisition protocols and computational models for accurate MR-based CT synthesis for use in RT. We investigate different categories of methods for CT synthesis and validate them using clinically relevant quality measures. Specifically, we implement a patch-based multi-atlas method in the brain, which compares favorably to state-of-the-art methods. In our next effort, we substantially improve the speed of the method and apply it in the pelvis, again with promising results. Our final contribution is a voxel-based method, which is developed to be registration-free and broadly applicable. In initial results, the performance of this method is close to the patch-based.</div></div><div class="phddissertation"><table class="properties"><tbody><tr class="language"><th>Original language</th><td>English</td></tr></tbody></table><table class="properties"><tbody><tr><th>Place of Publication</th><td>Kgs. Lyngby</td></tr><tr><th>Publisher</th><td><a rel="Publisher" href="http://orbit.dtu.dk/en/publishers/technical-university-of-denmark-dtu(f7c040ab-194a-4da4-b458-670da24b2a08).html" class="link"><span>Technical University of Denmark (DTU)</span></a></td></tr><tr><th>Number of pages</th><td>72</td></tr><tr class="status"><th>State</th><td><span class="prefix">Submitted - </span><span class="date">2016</span></td></tr></tbody></table></div> <table class="properties"><tbody><tr><th>Name</th><td>DTU Compute PHD-2016</td></tr><tr><th>Number</th><td>428</td></tr><tr><th>ISSN (print)</th><td>0909-3192</td></tr></tbody></table></div></div>Thu, 31 Dec 2015 23:00:00 GMThttp://orbit.dtu.dk/en/publications/an-investigation-of-methods-for-ct-synthesis-in-mronly-radiotherapy(9a1a2093-e7f9-4415-8233-dad1ba5460ff).html2015-12-31T23:00:00ZOptimization on Spaces of Curves
http://orbit.dtu.dk/en/publications/optimization-on-spaces-of-curves(6ffa726c-50ce-416f-a64b-0b3f40bb70be).html
<div style='font-size: 9px;'><div class="rendering rendering_publication rendering_publication_short rendering_bookanthology rendering_short rendering_bookanthology_short"><h2 class="title"><a rel="BookAnthology" href="http://orbit.dtu.dk/en/publications/optimization-on-spaces-of-curves(6ffa726c-50ce-416f-a64b-0b3f40bb70be).html" class="link"><span>Optimization on Spaces of Curves</span></a></h2><a rel="Person" href="http://orbit.dtu.dk/en/persons/jakob-moellerandersen(4d0b40f9-31c1-497c-acef-e6f5660a42ff).html" class="link person"><span>Møller-Andersen, J.</span></a> & <a rel="Person" href="http://orbit.dtu.dk/en/persons/jens-gravesen(c4148734-4026-46f6-ac0d-8ddd781fb0b0).html" class="link person"><span>Gravesen, J.</span></a> <span class="date">2016</span> Kgs. Lyngby: <a rel="Publisher" href="http://orbit.dtu.dk/en/publishers/technical-university-of-denmark-dtu(f7c040ab-194a-4da4-b458-670da24b2a08).html" class="link"><span>Technical University of Denmark (DTU)</span></a>. <span class="numberofpages">113 p.</span> (DTU Compute PHD-2016; No. 432).<p class="type"><span class="type_family">Publication<span class="type_family_sep">: </span></span><span class="type_classification_parent">Research<span class="type_parent_sep"> › </span></span><span class="type_classification">Ph.D. thesis – Annual report year: 2016</span></p></div><div class="rendering rendering_publication rendering_publication_detailsportal rendering_bookanthology rendering_detailsportal rendering_bookanthology_detailsportal"><div class="abstract"><div class="textblock">This thesis is concerned with computational and theoretical aspects of Riemannian metrics on spaces of regular curves, and their applications. It was recently proved that second order constant coefficient Sobolev metrics on curves are geodesically complete. We extend this result to the case of Sobolev metrics with coefficient functions depending on the length of the curve. We show how to apply this result to analyse a wide range of metrics on the submanifold of unit and constant speed curves.<br /><br />We present a numerical discretization of second order Sobolev metrics on the space of regular curves in R<sup>d</sup>, and methods to solve the initial and boundary value problem for geodesics allowing us to compute the Karcher mean and principal components analysis of data of curves. We apply the methods to study shape variation in synthetic data in the Kimia shape database, in HeLa cell nuclei and cycles of cardiac deformations.<br /><br />Finally we investigate a new application of Riemannian shape analysis in shape optimization. We setup a simple elliptic model problem, and describe how to apply shape calculus to obtain directional derivatives in the manifold of planar curves. We present an implementation based on parametrization of immersions by B-splines, which ties in naturally with Isogeometric Analysis to solve the PDE. We give numerical examples of solutions, and compare the Riemannian optimization algorithms with different choices of metrics to a naive unregularized discretize-first approach.</div></div><div class="phddissertation"><table class="properties"><tbody><tr class="language"><th>Original language</th><td>English</td></tr></tbody></table><table class="properties"><tbody><tr><th>Place of Publication</th><td>Kgs. Lyngby</td></tr><tr><th>Publisher</th><td><a rel="Publisher" href="http://orbit.dtu.dk/en/publishers/technical-university-of-denmark-dtu(f7c040ab-194a-4da4-b458-670da24b2a08).html" class="link"><span>Technical University of Denmark (DTU)</span></a></td></tr><tr><th>Number of pages</th><td>113</td></tr><tr class="status"><th>State</th><td><span class="prefix">Submitted - </span><span class="date">2016</span></td></tr></tbody></table></div> <table class="properties"><tbody><tr><th>Name</th><td>DTU Compute PHD-2016</td></tr><tr><th>Number</th><td>432</td></tr><tr><th>ISSN (print)</th><td>0909-3192</td></tr></tbody></table></div></div>Thu, 31 Dec 2015 23:00:00 GMThttp://orbit.dtu.dk/en/publications/optimization-on-spaces-of-curves(6ffa726c-50ce-416f-a64b-0b3f40bb70be).html2015-12-31T23:00:00ZGraph Decompositions
http://orbit.dtu.dk/en/publications/graph-decompositions(26078582-4966-4501-bd83-484a67719c67).html
<div style='font-size: 9px;'><div class="rendering rendering_publication rendering_publication_short rendering_bookanthology rendering_short rendering_bookanthology_short"><h2 class="title"><a rel="BookAnthology" href="http://orbit.dtu.dk/en/publications/graph-decompositions(26078582-4966-4501-bd83-484a67719c67).html" class="link"><span>Graph Decompositions</span></a></h2><a rel="Person" href="http://orbit.dtu.dk/en/persons/martin-merker(73c783d1-127e-4a6e-9a3b-919312c24dd2).html" class="link person"><span>Merker, M.</span></a> & <a rel="Person" href="http://orbit.dtu.dk/en/persons/carsten-thomassen(88ab66ea-2b88-44e7-88f2-b8b883cf3ec0).html" class="link person"><span>Thomassen, C.</span></a> <span class="date">2016</span> Kgs. Lyngby: <a rel="Publisher" href="http://orbit.dtu.dk/en/publishers/technical-university-of-denmark-dtu(f7c040ab-194a-4da4-b458-670da24b2a08).html" class="link"><span>Technical University of Denmark (DTU)</span></a>. <span class="numberofpages">97 p.</span> (DTU Compute PHD-2016; No. 431).<p class="type"><span class="type_family">Publication<span class="type_family_sep">: </span></span><span class="type_classification_parent">Research<span class="type_parent_sep"> › </span></span><span class="type_classification">Ph.D. thesis – Annual report year: 2016</span></p></div><div class="rendering rendering_publication rendering_publication_detailsportal rendering_bookanthology rendering_detailsportal rendering_bookanthology_detailsportal"><div class="abstract"><div class="textblock">The topic of this PhD thesis is graph decompositions. While there exist various kinds of decompositions, this thesis focuses on three problems concerning edgedecompositions. Given a family of graphs H we ask the following question: When can the edge-set of a graph be partitioned so that each part induces a subgraph isomorphic to a member of H? Such a decomposition is called an H-decomposition. Apart from the existence of an H-decomposition, we are also interested in the number of parts needed in an H-decomposition. <br /><br />Firstly, we show that for every tree T there exists a constant k(T) such that every k(T)-edge-connected graph whose size is divisible by the size of T admits a T-decomposition. This proves a conjecture by Barát and Thomassen from 2006.<br /><br />Moreover, we introduce a new arboricity notion where we restrict the diameter of the trees in a decomposition into forests. We conjecture that for every natural number k there exists a natural number d(k) such that the following holds: If G can be decomposed into k forests, then G can be decomposed into k + 1 forests in which each tree has diameter at most d(k). We verify this conjecture for<br />k ≤ 3. As an application we show that every 6-edge-connected planar graph contains two edge-disjoint 18/19 -thin spanning trees.<br /><br />Finally, we make progress on a conjecture by Baudon, Bensmail, Przybyło, and Wozniak stating that if a graph can be decomposed into locally irregular graphs, then there exists such a decomposition with at most 3 parts. We show that this conjecture is true if the number 3 is replaced by 328, establishing the first constant upper bound for this problem.</div></div><div class="phddissertation"><table class="properties"><tbody><tr class="language"><th>Original language</th><td>English</td></tr></tbody></table><table class="properties"><tbody><tr><th>Place of Publication</th><td>Kgs. Lyngby</td></tr><tr><th>Publisher</th><td><a rel="Publisher" href="http://orbit.dtu.dk/en/publishers/technical-university-of-denmark-dtu(f7c040ab-194a-4da4-b458-670da24b2a08).html" class="link"><span>Technical University of Denmark (DTU)</span></a></td></tr><tr><th>Number of pages</th><td>97</td></tr><tr class="status"><th>State</th><td><span class="prefix">Submitted - </span><span class="date">2016</span></td></tr></tbody></table></div> <table class="properties"><tbody><tr><th>Name</th><td>DTU Compute PHD-2016</td></tr><tr><th>Number</th><td>431</td></tr><tr><th>ISSN (print)</th><td>0909-3192</td></tr></tbody></table></div></div>Thu, 31 Dec 2015 23:00:00 GMThttp://orbit.dtu.dk/en/publications/graph-decompositions(26078582-4966-4501-bd83-484a67719c67).html2015-12-31T23:00:00ZImage reconstruction under non-Gaussian noise
http://orbit.dtu.dk/en/publications/image-reconstruction-under-nongaussian-noise(38fa38ee-f1db-4021-92ef-b9cb27e4adfb).html
<div style='font-size: 9px;'><div class="rendering rendering_publication rendering_publication_short rendering_bookanthology rendering_short rendering_bookanthology_short"><h2 class="title"><a rel="BookAnthology" href="http://orbit.dtu.dk/en/publications/image-reconstruction-under-nongaussian-noise(38fa38ee-f1db-4021-92ef-b9cb27e4adfb).html" class="link"><span>Image reconstruction under non-Gaussian noise</span></a></h2><a rel="Person" href="http://orbit.dtu.dk/en/persons/federica-sciacchitano(595c3287-b609-4c3e-a8db-a390a74df2b1).html" class="link person"><span>Sciacchitano, F.</span></a>, <a rel="Person" href="http://orbit.dtu.dk/en/persons/yiqiu-dong(fbd1dafa-2d1c-4149-85b8-8998ea308e5f).html" class="link person"><span>Dong, Y.</span></a> & <a rel="Person" href="http://orbit.dtu.dk/en/persons/per-christian-hansen(6c6c6f32-e3b2-40d5-a407-aa8e2f051f7b).html" class="link person"><span>Hansen, P. C.</span></a> <span class="date">2016</span> Kgs. Lyngby: <a rel="Publisher" href="http://orbit.dtu.dk/en/publishers/technical-university-of-denmark-dtu(f7c040ab-194a-4da4-b458-670da24b2a08).html" class="link"><span>Technical University of Denmark (DTU)</span></a>. <span class="numberofpages">115 p.</span> (DTU Compute PHD-2016; No. 426).<p class="type"><span class="type_family">Publication<span class="type_family_sep">: </span></span><span class="type_classification_parent">Research<span class="type_parent_sep"> › </span></span><span class="type_classification">Ph.D. thesis – Annual report year: 2016</span></p></div><div class="rendering rendering_publication rendering_publication_detailsportal rendering_bookanthology rendering_detailsportal rendering_bookanthology_detailsportal"><div class="abstract"><div class="textblock">During acquisition and transmission, images are often blurred and corrupted by noise. One of the fundamental tasks of image processing is to reconstruct the clean image from a degraded version. The process of recovering the original image from the data is an example of inverse problem. Due to the ill-posedness of the problem, the simple inversion of the degradation model does not give any good reconstructions. Therefore, to deal with the ill-posedness it is necessary to use some prior information on the solution or the model and the Bayesian approach.<br /><br />Additive Gaussian noise has been extensively studied since it produces simple and tractable mathematical models. However, in the real applications, the noise is much more complicated and it cannot be well simulated by additive Gaussian noise, for instance, it may be signal dependent, very impulsive, multiplicative, mixed, etc. This PhD thesis intends to solve some of the many open questions for image restoration under non-Gaussian noise. The two main kinds of noise studied in this PhD project are the impulse noise and the Cauchy noise.<br /><br />Impulse noise is due to for instance the malfunctioning pixel elements in the camera sensors, errors in analogue-to-digital conversion, faulty memory locations in hardware. Cauchy noise is characterized by a very impulsive behaviour and it is mainly used to simulate atmospheric and underwater acoustic noise, in radar and sonar applications, biomedical images and synthetic aperture radar images. For both noise models we introduce new variational models to recover the clean and sharp images from degraded images. Both methods are veri_ed by using some simulated test problems. The experiments clearly show that the new methods outperform the former ones.<br /><br />Furthermore, we have carried out a theoretical study on the two most known estimates:<br />maximum a posteriori (MAP) estimate and conditional mean (CM) estimate for non-Gaussian noise. With only the convexity assumption on the data _delity term, we introduce some cost functions for which the CM and MAP estimates are proper Bayes estimators and we also prove that the CM estimate outperforms the MAP estimate, when the error depends on Bregman distances.<br /><br />This PhD project can have many applications in the modern society, in fact the reconstruction of high quality images with less noise and more details enhances the image processing operations, such as edge detection, segmentation, etc.</div></div><div class="phddissertation"><table class="properties"><tbody><tr class="language"><th>Original language</th><td>English</td></tr></tbody></table><table class="properties"><tbody><tr><th>Place of Publication</th><td>Kgs. Lyngby</td></tr><tr><th>Publisher</th><td><a rel="Publisher" href="http://orbit.dtu.dk/en/publishers/technical-university-of-denmark-dtu(f7c040ab-194a-4da4-b458-670da24b2a08).html" class="link"><span>Technical University of Denmark (DTU)</span></a></td></tr><tr><th>Number of pages</th><td>115</td></tr><tr class="status"><th>State</th><td><span class="prefix">Submitted - </span><span class="date">2016</span></td></tr></tbody></table></div> <table class="properties"><tbody><tr><th>Name</th><td>DTU Compute PHD-2016</td></tr><tr><th>Number</th><td>426</td></tr><tr><th>ISSN (print)</th><td>0909-3192</td></tr></tbody></table></div></div>Thu, 31 Dec 2015 23:00:00 GMThttp://orbit.dtu.dk/en/publications/image-reconstruction-under-nongaussian-noise(38fa38ee-f1db-4021-92ef-b9cb27e4adfb).html2015-12-31T23:00:00ZEnhancing User Experience in Next Generation Mobile Devices Using Eye Tracking as a Biometric Sensor
http://orbit.dtu.dk/en/publications/enhancing-user-experience-in-next-generation-mobile-devices-using-eye-tracking-as-a-biometric-sensor(2562ac71-373f-46e6-b88c-6c64589cde86).html
<div style='font-size: 9px;'><div class="rendering rendering_publication rendering_publication_short rendering_bookanthology rendering_short rendering_bookanthology_short"><h2 class="title"><a rel="BookAnthology" href="http://orbit.dtu.dk/en/publications/enhancing-user-experience-in-next-generation-mobile-devices-using-eye-tracking-as-a-biometric-sensor(2562ac71-373f-46e6-b88c-6c64589cde86).html" class="link"><span>Enhancing User Experience in Next Generation Mobile Devices Using Eye Tracking as a Biometric Sensor</span></a></h2><a rel="Person" href="http://orbit.dtu.dk/en/persons/per-baekgaard(c7b6e25e-b81b-402f-81c1-7e6ef56e2334).html" class="link person"><span>Bækgaard, P.</span></a>, <a rel="Person" href="http://orbit.dtu.dk/en/persons/michael-kai-petersen(0184dad5-da00-4ca8-b00a-53165ce84766).html" class="link person"><span>Petersen, M. K.</span></a> & <a rel="Person" href="http://orbit.dtu.dk/en/persons/jakob-eg-larsen(691c8ae7-9a21-4b98-9b91-5e2d9806a4b9).html" class="link person"><span>Larsen, J. E.</span></a> <span class="date">2016</span> Kgs. Lyngby: <a rel="Publisher" href="http://orbit.dtu.dk/en/publishers/technical-university-of-denmark-dtu(f7c040ab-194a-4da4-b458-670da24b2a08).html" class="link"><span>Technical University of Denmark (DTU)</span></a>. <span class="numberofpages">234 p.</span> (DTU Compute PHD-2016; No. 433).<p class="type"><span class="type_family">Publication<span class="type_family_sep">: </span></span><span class="type_classification_parent">Research<span class="type_parent_sep"> › </span></span><span class="type_classification">Ph.D. thesis – Annual report year: 2016</span></p></div><div class="rendering rendering_publication rendering_publication_detailsportal rendering_bookanthology rendering_detailsportal rendering_bookanthology_detailsportal"><div class="abstract"><div class="textblock">A good User Experience is not about just “getting the job done” in the most efficient way. It is also about the subjective elements, providing a positive experience to the user while doing so; emotionally and affectively, having the user engage with the service or product.<br /><br />Knowing when this takes place means we need ways of measuring concepts like attention. The basis for this should preferably be rooted in our understanding of the anatomically based attention networks of the brain. <br /><br />This thesis looks at biometric markers of cognitive and affective processes; at the overview level Electroencephalography (EEG), Galvanic Skin Conductance (GSR), Heart Rate and Heart Rate Variability as well as Face Expression Detection – and in much more detail Eye Tracking.<br /><br />A simple framework for relating eye movements and pupil dilations to the visual processing system and to the attentional networks is suggested. It is demonstrated that it is possible to identify components of attention and cognitive load using low cost eye tracking in conventional office settings. It is also shown that aspects of surprise, similar to negativity feedback error coding, is measurable. Behavioural patterns possibly related to time on target, cognitive load, performance or stimuli are inferred. The existence of possibly unique individual gaze patterns related to visual stimuli or to the brain’s Default Mode Network are shown. <br /><br />A way of synchronizing EEG and Eye Tracking is also suggested, and in addition, a few software assets (a Python interface to The Eye Tribe tracker and an implementation of the Attention Network Test (ANT)) have been created.</div></div><div class="phddissertation"><table class="properties"><tbody><tr class="language"><th>Original language</th><td>English</td></tr></tbody></table><table class="properties"><tbody><tr><th>Place of Publication</th><td>Kgs. Lyngby</td></tr><tr><th>Publisher</th><td><a rel="Publisher" href="http://orbit.dtu.dk/en/publishers/technical-university-of-denmark-dtu(f7c040ab-194a-4da4-b458-670da24b2a08).html" class="link"><span>Technical University of Denmark (DTU)</span></a></td></tr><tr><th>Number of pages</th><td>234</td></tr><tr class="status"><th>State</th><td><span class="prefix">Submitted - </span><span class="date">2016</span></td></tr></tbody></table></div> <table class="properties"><tbody><tr><th>Name</th><td>DTU Compute PHD-2016</td></tr><tr><th>Number</th><td>433</td></tr><tr><th>ISSN (print)</th><td>0909-3192</td></tr></tbody></table></div></div>Thu, 31 Dec 2015 23:00:00 GMThttp://orbit.dtu.dk/en/publications/enhancing-user-experience-in-next-generation-mobile-devices-using-eye-tracking-as-a-biometric-sensor(2562ac71-373f-46e6-b88c-6c64589cde86).html2015-12-31T23:00:00ZMultilevel techniques for Reservoir Simulation
http://orbit.dtu.dk/en/publications/multilevel-techniques-for-reservoir-simulation(028e4f44-aa92-4c3a-b553-7bee9a76ed36).html
<div style='font-size: 9px;'><div class="rendering rendering_publication rendering_publication_short rendering_bookanthology rendering_short rendering_bookanthology_short"><h2 class="title"><a rel="BookAnthology" href="http://orbit.dtu.dk/en/publications/multilevel-techniques-for-reservoir-simulation(028e4f44-aa92-4c3a-b553-7bee9a76ed36).html" class="link"><span>Multilevel techniques for Reservoir Simulation</span></a></h2><a rel="Person" href="http://orbit.dtu.dk/en/persons/max-la-cour-christensen(4fc8cc48-7d39-4a46-863e-a03f00c4cbf3).html" class="link person"><span>Christensen, M. L. C.</span></a> & <a rel="Person" href="http://orbit.dtu.dk/en/persons/allan-peter-engsigkarup(f2fda3c5-b5fe-40c8-9cf4-e2bab14c176b).html" class="link person"><span>Engsig-Karup, A. P.</span></a> <span class="date">2016</span> Kgs. Lyngby: <a rel="Publisher" href="http://orbit.dtu.dk/en/publishers/technical-university-of-denmark-dtu(f7c040ab-194a-4da4-b458-670da24b2a08).html" class="link"><span>Technical University of Denmark (DTU)</span></a>. <span class="numberofpages">213 p.</span> (DTU Compute PHD-2016; No. 430).<p class="type"><span class="type_family">Publication<span class="type_family_sep">: </span></span><span class="type_classification_parent">Research<span class="type_parent_sep"> › </span></span><span class="type_classification">Ph.D. thesis – Annual report year: 2016</span></p></div><div class="rendering rendering_publication rendering_publication_detailsportal rendering_bookanthology rendering_detailsportal rendering_bookanthology_detailsportal"><div class="abstract"><div class="textblock">The subject of this thesis is the development, application and study of novel multilevel methods for the acceleration and improvement of reservoir simulation techniques. The motivation for addressing this topic is a need for more accurate predictions of porous media flow and the ability to carry out these computations in a timely manner. This will lead to better decision making in the production of oil and gas. The goal is attained in various ways throughout the thesis work. Specifically, three fields of multilevel methods have been addressed in this work, namely<br /><br />• Nonlinear multigrid (the Full Approximation Scheme)<br />• Variational (Galerkin) upscaling<br />• Linear solvers and preconditioners<br /><br />First, a nonlinear multigrid scheme in the form of the Full Approximation Scheme (FAS) is implemented and studied for a 3D three-phase compressible rock/fluids immiscible reservoir simulator with a coupled well model. In a fair way, it is compared to the state-of-the-art solution scheme used in industry and research simulators. It is found that FAS improves time-to-solution by having a larger basin of attraction, faster initial convergence, data locality and a lower memory footprint. The study is extended to include a hybrid strategy, where FAS is combined with Newton’s method to construct a multilevel nonlinear preconditioner. This method demonstrates high efficiency and robustness. <br /><br />Second, an improved IMPES formulated reservoir simulator is implemented using a novel variational upscaling approach based on element-based Algebraic Multigrid (AMGe). In particular, an advanced AMGe technique with guaranteed approximation properties is used to construct a coarse multilevel hierarchy of Raviart-Thomas and L2 spaces for the Galerkin coarsening of a mixed formulation of the reservoir simulation equations. By experimentation it is found that the AMGe based upscaling technique provided very accurate results while reducing the computational time proportionally to the reduction in degrees of freedom. Furthermore, it is demonstrated that the AMGe coarse spaces (interpolation operators) can be used for both variational upscaling and the construction of linear solvers. In particular, it is found to be beneficial (or even necessary) to apply an AMGe based multigrid solver to solve the upscaled problems. It is found that the AMGe upscaling changes the spectral properties of the matrix, which renders well-known state-of-the-art solvers for this type of system useless.<br /><br />Third, FAS is combined with AMGe with guaranteed approximation properties to obtain a nonlinear multigrid solver for unstructured meshes. The FAS-AMGe solver is applied to a simplistic but numerically challenging mixed (velocity/-pressure) model for porous media flow. In a fair way, FAS-AMGe is compared to Newton’s method and Picard iterations. It is found that FAS-AMGe is faster for the cases considered.<br /><br />Finally, a number of multigrid linear solvers and preconditioners are implemented for various linear systems. In particular AMGe are used in the construction of multigrid preconditioners. These are compared to two state-of-the-art block diagonal preconditioners based on 1) a Schur complement with an Algebraic Multigrid (AMG) solver and 2) an augmented Lagrangian formulation using the Auxiliary Space AMG solver.<br /><br />In addition to the research mentioned above, a sequential in-house COmpositional reservoir SImulator (COSI) with many features is parallelized in a distributed setting (MPI) using the PETSc framework. A parallel preconditioner based on the Constrained Pressure Residual method, Algebraic Multigrid and Restricted Additive Overlapping Schwarz with Incomplete LU solves on each subdomain is implemented. It is found that switching the traditionally used method, namely parallel ILU, with Restricted Additive Overlapping Schwarz results in a significant increase in parallel scalability while still maintaining similar robustness and efficiency.</div></div><div class="phddissertation"><table class="properties"><tbody><tr class="language"><th>Original language</th><td>English</td></tr></tbody></table><table class="properties"><tbody><tr><th>Place of Publication</th><td>Kgs. Lyngby</td></tr><tr><th>Publisher</th><td><a rel="Publisher" href="http://orbit.dtu.dk/en/publishers/technical-university-of-denmark-dtu(f7c040ab-194a-4da4-b458-670da24b2a08).html" class="link"><span>Technical University of Denmark (DTU)</span></a></td></tr><tr><th>Number of pages</th><td>213</td></tr><tr class="status"><th>State</th><td><span class="prefix">Submitted - </span><span class="date">2016</span></td></tr></tbody></table></div> <table class="properties"><tbody><tr><th>Name</th><td>DTU Compute PHD-2016</td></tr><tr><th>Number</th><td>430</td></tr><tr><th>ISSN (print)</th><td>0909-3192</td></tr></tbody></table></div></div>Thu, 31 Dec 2015 23:00:00 GMThttp://orbit.dtu.dk/en/publications/multilevel-techniques-for-reservoir-simulation(028e4f44-aa92-4c3a-b553-7bee9a76ed36).html2015-12-31T23:00:00ZCharacterization of absorption enhancers for orally administered therapeutic peptides in tablet formulations - Applying statistical learning
http://orbit.dtu.dk/en/publications/characterization-of-absorption-enhancers-for-orally-administered-therapeutic-peptides-in-tablet-formulations--applying-statistical-learning(7a231e4a-dd35-4c7a-9ea9-5992eae7cf2a).html
<div style='font-size: 9px;'><div class="rendering rendering_publication rendering_publication_short rendering_bookanthology rendering_short rendering_bookanthology_short"><h2 class="title"><a rel="BookAnthology" href="http://orbit.dtu.dk/en/publications/characterization-of-absorption-enhancers-for-orally-administered-therapeutic-peptides-in-tablet-formulations--applying-statistical-learning(7a231e4a-dd35-4c7a-9ea9-5992eae7cf2a).html" class="link"><span>Characterization of absorption enhancers for orally administered therapeutic peptides in tablet formulations - Applying statistical learning</span></a></h2><a rel="Person" href="http://orbit.dtu.dk/en/persons/soeren-havelund-welling(5b5a1379-6f2e-48bb-b295-85f808fd0d3b).html" class="link person"><span>Welling, S. H.</span></a> & <a rel="Person" href="http://orbit.dtu.dk/en/persons/per-b-brockhoff(3feab848-c4ad-40fd-a9eb-73155faa15d3).html" class="link person"><span>Brockhoff, P. B.</span></a> <span class="date">2016</span> Kgs. Lyngby: <a rel="Publisher" href="http://orbit.dtu.dk/en/publishers/technical-university-of-denmark-dtu(f7c040ab-194a-4da4-b458-670da24b2a08).html" class="link"><span>Technical University of Denmark (DTU)</span></a>. <span class="numberofpages">212 p.</span> (DTU Compute PHD-2016; No. 429).<p class="type"><span class="type_family">Publication<span class="type_family_sep">: </span></span><span class="type_classification_parent">Research<span class="type_parent_sep"> › </span></span><span class="type_classification">Ph.D. thesis – Annual report year: 2016</span></p></div><div class="rendering rendering_publication rendering_publication_detailsportal rendering_bookanthology rendering_detailsportal rendering_bookanthology_detailsportal"><div class="abstract"><div class="textblock">To develop a successful an oral formulation of insulin for treatment of type-2 diabetes patients would be a great mile stone in terms of convenience. Besides protecting insulin from enzymatic cleavage in the small intestine, the formulation must overcome the intestinal epithelia barrier. Absorption enhancers are needed to ensure even a few percent of insulin are taken up. In thesis article 1, various methods to measure the effect of absorption enhancement and enzyme stability of insulin were applied. The major class of absorption enhancers is surfactant-like enhancers and is thought to promote absorption by mildly perturbing the epithelial membranes of the small intestine. The Caco-2 (Carcinoma Colon) cells can grow an artificial epithelial layer, and are used to test the potency of new absorption enhancers. This project was aimed to identify new absorption enhancers, that are both potent and sufficiently soluble. Quantitative structural activity relationship (QSAR) modeling is an empiric approach to learn relationships between molecular formulas and the biochemical properties using statistical models. A public data set testing the potency of absorption enhancers in Caco-2 was used to build a QSAR model to screen for new potent permeation enhancers. Thesis article 2 contains likely the first QSAR model to predict absorption enhancement. The model was verified by predicting molecules not tested before in Caco-2. The Caco-2 model overestimates the clinical effect of lipophilic permeation enhancers. In the Caco-2 model all reagents are pre-dissolved, and therefore the assay cannot predict critical solubility issues and bile salt interactions in the final tablet formulation. A QSAR solubility model was built to foresee and avoid slow tablet dissolution. Due to enzyme kinetics, slow tablet dissolution will allow most insulin to be deactivated by intestinal enzymes. The combined predictions of potency and solubility, will likely provide a more useful in-silico screening of potential permeation enhancers.<br /><br />Random forest was used to learn relationships between molecular descriptors and potency or solubility. However, unlike multiple linear regression, the explicitly stated random forest model is complex, and therefore difficult to interpret and communicate. Any supervised regression model can be understood as a high dimensional surface connecting any possible combination of molecular properties with a given prediction. This high dimensional surface is also difficult to comprehend, but for random forests, it was discovered that a method, feature contributions, was especially useful to decompose and visualize model structures. The visualization technique was named forest floor and could replace the otherwise widely use technique partial dependence plots, especially in terms of discovering interactions in the model structure. Thesis article 3 describes the forest floor method. An R package forestFloor was developed to compute feature contributions and visualize these according to the ideas of thesis article 3. Better interpretation of random forest models is an exciting interdisciplinary field, as it allows investigators of many backgrounds to find fairly complicated relationships in data sets without in advance specifying what parameters to estimate. Forest floor was used to explain how potency and solubility were predicted by random forest models.</div></div><div class="phddissertation"><table class="properties"><tbody><tr class="language"><th>Original language</th><td>English</td></tr></tbody></table><table class="properties"><tbody><tr><th>Place of Publication</th><td>Kgs. Lyngby</td></tr><tr><th>Publisher</th><td><a rel="Publisher" href="http://orbit.dtu.dk/en/publishers/technical-university-of-denmark-dtu(f7c040ab-194a-4da4-b458-670da24b2a08).html" class="link"><span>Technical University of Denmark (DTU)</span></a></td></tr><tr><th>Number of pages</th><td>212</td></tr><tr class="status"><th>State</th><td><span class="prefix">Submitted - </span><span class="date">2016</span></td></tr></tbody></table></div> <table class="properties"><tbody><tr><th>Name</th><td>DTU Compute PHD-2016</td></tr><tr><th>Number</th><td>429</td></tr><tr><th>ISSN (print)</th><td>0909-3192</td></tr></tbody></table></div></div>Thu, 31 Dec 2015 23:00:00 GMThttp://orbit.dtu.dk/en/publications/characterization-of-absorption-enhancers-for-orally-administered-therapeutic-peptides-in-tablet-formulations--applying-statistical-learning(7a231e4a-dd35-4c7a-9ea9-5992eae7cf2a).html2015-12-31T23:00:00ZTowards Plug-n-Play robot guidance: Advanced 3D estimation and pose estimation in Robotic applications
http://orbit.dtu.dk/en/publications/towards-plugnplay-robot-guidance-advanced-3d-estimation-and-pose-estimation-in-robotic-applications(96d95a07-3e64-4888-ba53-db6741f09f66).html
<div style='font-size: 9px;'><div class="rendering rendering_publication rendering_publication_short rendering_bookanthology rendering_short rendering_bookanthology_short"><h2 class="title"><a rel="BookAnthology" href="http://orbit.dtu.dk/en/publications/towards-plugnplay-robot-guidance-advanced-3d-estimation-and-pose-estimation-in-robotic-applications(96d95a07-3e64-4888-ba53-db6741f09f66).html" class="link"><span>Towards Plug-n-Play robot guidance: Advanced 3D estimation and pose estimation in Robotic applications</span></a></h2><a rel="Person" href="http://orbit.dtu.dk/en/persons/thomas-soelund(64b614e9-855f-4be9-b2fe-d42586e9e18e).html" class="link person"><span>Sølund, T.</span></a> & <a rel="Person" href="http://orbit.dtu.dk/en/persons/henrik-aanaes(82129afb-048a-424a-ba22-419bd0bab56f).html" class="link person"><span>Aanæs, H.</span></a> <span class="date">2016</span> Kgs. Lyngby: <a rel="Publisher" href="http://orbit.dtu.dk/en/publishers/technical-university-of-denmark-dtu(f7c040ab-194a-4da4-b458-670da24b2a08).html" class="link"><span>Technical University of Denmark (DTU)</span></a>. <span class="numberofpages">179 p.</span> (DTU Compute PHD-2016; No. 424).<p class="type"><span class="type_family">Publication<span class="type_family_sep">: </span></span><span class="type_classification_parent">Research<span class="type_parent_sep"> › </span></span><span class="type_classification">Ph.D. thesis – Annual report year: 2016</span></p></div><div class="rendering rendering_publication rendering_publication_detailsportal rendering_bookanthology rendering_detailsportal rendering_bookanthology_detailsportal"><div class="abstract"><div class="textblock">Robots are a key technology in the quest for higher productivity in Denmark and Europe. Robots have existed in many years as a part of production lines where they have solved monotonous and repetitive task in mass production industries. Typical the programming of these robots are handled by engineers with special knowledge who have often raised the price for using robots to a given production task. If robots have to be applicable for small and medium sized enterprises where production task often changes and batch sizes are below 50 products it is necessary that the staff is capable of re-programming the robot by themselves. <br /><br />During the last five years a number of collaborative robots are introduced on the marked e.g. Universal Robot, which enables a production worker to program the robot to solve simple tasks. With the collaborative robot the production worker is able to make the robot grind, mill, weld and move objects, which are physical located at the same positions. In order to place objects in the same position each time, custom-made mechanical fixtures and aligners are constructed to ensure that objects are not moving. It is expensive to design and build these fixtures and it is difficult to quickly change to a novel task. In some cases where objects are placed in bins and boxes it is not possible to position the objects in the same location each time.<br /><br />To avoid designing expensive mechanical solutions and to be able to pick objects from boxes and bins, a sensor is necessary to guide the robot. Today, primarily 2D vision systems are applied in industrial robotics, which are in-flexible and hard to program for the production workers. Smart cameras, which are easier to re-configure and program to detect objects exist. However, computing the correct position such that a robot can move to this position is still a challenge which requires calibration processes. Moreover, the ability to make the solution robust such that it is running 24/7 in a production is demanding and requires the right skills. Basically, the vision part of a flexible automation solution is difficult to manage for a production worker while the robot motion programming is easily handled with the new collaborative robots. This thesis deals with robot vision technologies and how these are made easier for production workers program in order to get robots to recognize and compute the position of objects in the industry.<br /><br />This thesis investigates and discusses methods to encapsulate a 2D vision system into a framework in order to make changes in production task easier. The framework is presented in [Contribution B] and [Contribution C] and demonstrates how re-configuration of vision systems is made easier but in the same time reviles some of the fundamental problems that exist by observing a tree dimensional world through a two dimensional vision system. This requires a calibration procedure every time in order to convert 2D to 3D, which still is a cumbersome process for a production worker.<br /><br />For this reason, the rest of the thesis investigates and discusses how 3D computer vision techniques can ease the problem of recognizing and computing the position of objects. In [Contribution D] a small lightweight 3D sensor is presented. The 3D sensor has a size that makes it suitable for tool mounting at a collaborative robot. It is based on structured light principles and 3D estimation techniques, which enables fast and accurate acquisition of point clouds of low textured and reflective industrial objects.<br /><br />In [Contribution E] a 3D vision system for easy learning of 3D models is presented. The system creates a 3D model of the object by scanning it from three views. Then the object acts as a reference model in the system when new instances of the object have to be located in the scene. With this approach fast re-configuration is possible. In [Contribution F] a new dataset for 3D object recognition and an evaluation of state-of-the-art local features for object recognition are presented. The contribution shows as expected that state-of-the-art 3D object recognition algorithms are not good enough to locate industrial objects with few local shape features on the surface.</div></div><div class="phddissertation"><table class="properties"><tbody><tr class="language"><th>Original language</th><td>English</td></tr></tbody></table><table class="properties"><tbody><tr><th>Place of Publication</th><td>Kgs. Lyngby</td></tr><tr><th>Publisher</th><td><a rel="Publisher" href="http://orbit.dtu.dk/en/publishers/technical-university-of-denmark-dtu(f7c040ab-194a-4da4-b458-670da24b2a08).html" class="link"><span>Technical University of Denmark (DTU)</span></a></td></tr><tr><th>Number of pages</th><td>179</td></tr><tr class="status"><th>State</th><td><span class="prefix">Submitted - </span><span class="date">2016</span></td></tr></tbody></table></div> <table class="properties"><tbody><tr><th>Name</th><td>DTU Compute PHD-2016</td></tr><tr><th>Number</th><td>424</td></tr><tr><th>ISSN (print)</th><td>0909-3192</td></tr></tbody></table></div></div>Thu, 31 Dec 2015 23:00:00 GMThttp://orbit.dtu.dk/en/publications/towards-plugnplay-robot-guidance-advanced-3d-estimation-and-pose-estimation-in-robotic-applications(96d95a07-3e64-4888-ba53-db6741f09f66).html2015-12-31T23:00:00ZMarine Bacterial Genomics: an ocean of opportunity
http://orbit.dtu.dk/en/publications/marine-bacterial-genomics(db5982f4-fc63-4f5f-948f-ff4b562a2d87).html
<div style='font-size: 9px;'><div class="rendering rendering_publication rendering_publication_short rendering_bookanthology rendering_short rendering_bookanthology_short"><h2 class="title"><a rel="BookAnthology" href="http://orbit.dtu.dk/en/publications/marine-bacterial-genomics(db5982f4-fc63-4f5f-948f-ff4b562a2d87).html" class="link"><span>Marine Bacterial Genomics: an ocean of opportunity</span></a></h2><a rel="Person" href="http://orbit.dtu.dk/en/persons/henrique-machado(f3a05fb5-e2a3-410d-8788-a1dd1f0fd7fd).html" class="link person"><span>Machado, H.</span></a> & <a rel="Person" href="http://orbit.dtu.dk/en/persons/lone-gram(9fabd1ae-e28f-4a5d-8456-7a075b4aa34e).html" class="link person"><span>Gram, L.</span></a> <span class="date">2016</span> <a rel="Publisher" href="http://orbit.dtu.dk/en/publishers/technical-university-of-denmark-dtu(f7c040ab-194a-4da4-b458-670da24b2a08).html" class="link"><span>Technical University of Denmark (DTU)</span></a>. <span class="numberofpages">239 p.</span><p class="type"><span class="type_family">Publication<span class="type_family_sep">: </span></span><span class="type_classification_parent">Research<span class="type_parent_sep"> › </span></span><span class="type_classification">Ph.D. thesis – Annual report year: 2016</span></p></div><div class="rendering rendering_publication rendering_publication_detailsportal rendering_bookanthology rendering_detailsportal rendering_bookanthology_detailsportal"><div class="abstract"><div class="textblock">For decades, terrestrial microorganisms have been used as sources of countless enzymes and chemical compounds that have been produced by pharmaceutical and biotech companies and used by mankind. There is a need for new chemical compounds, including antibiotics,new enzymatic activities and new microorganisms to be used as cell factories for production. Therefore exploitation of new microbial niches and use of different strategies is an opportunity to boost discoveries. Even though scientists have started to explore several habitats other than the terrestrial ones, the marine environment stands out as a hitherto under-explored niche. This thesis work uses high-throughput sequencing technologies on a collection of marine bacteria established during the Galathea 3 expedition, with the purpose of unraveling new biodiversity and new bioactivities. Several tools were used for genomic analysis in order to better understand the potential harbored in marine bacteria. The work presented makes use of whole genome sequencing of marine bacteria to prove that the genetic repertoire for secondary metabolite production harbored in these bacteria is far larger than anticipated; to identify and develop a new phylogenetic marker for the identification of members of the <i>Vibrionaceae </i>family, which led to the identification of two new species using this straightforward pipeline;to discovery of new cytochrome P450 enzymes to be used in biotechnology; and to a thorough study of the marine genus <i>Photobacterium</i>, by means of comparative genomics. In conclusion, this PhD thesis has contributed to our understanding of the marine microbial environment by studying genomic information of several marine bacteria, expanding the number of marine species taxonomically described, providing identification tools for further marine species documentation and pointing to these organisms as a very promising resource for further bioprospecting.</div></div><div class="phddissertation"><table class="properties"><tbody><tr class="language"><th>Original language</th><td>English</td></tr></tbody></table><table class="properties"><tbody><tr><th>Publisher</th><td><a rel="Publisher" href="http://orbit.dtu.dk/en/publishers/technical-university-of-denmark-dtu(f7c040ab-194a-4da4-b458-670da24b2a08).html" class="link"><span>Technical University of Denmark (DTU)</span></a></td></tr><tr><th>Number of pages</th><td>239</td></tr><tr class="status"><th>State</th><td><span class="prefix">Published - </span><span class="date">2016</span></td></tr></tbody></table></div></div></div>Thu, 31 Dec 2015 23:00:00 GMThttp://orbit.dtu.dk/en/publications/marine-bacterial-genomics(db5982f4-fc63-4f5f-948f-ff4b562a2d87).html2015-12-31T23:00:00Z