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Many problems in computer vision can be turned into a large-scale boolean optimization problem, which is in general NP-hard. In this paper, we further develop one of the most successful approaches, namely roof duality, for approximately solving such problems for higher-order models. Two new methods that can be applied independently or in combination are investigated. The first one is based on cons
Abstract in UndeterminedIn this paper theoretical results regarding a generalized minimum rank matrix approximation problem in the spectral norm are presented. An alternative solution expression for the generalized matrix approximation problem is obtained. This alternative expression provides a simple characterization of the achievableminimum rank, which is shown to be the same as the optimal obje
A distributed model predictive control (DMPC) approach based on distributed optimization is applied to the power reference tracking problem of a hydro power valley (HPV) system. The applied optimization algorithm is based on accelerated gradient methods and achieves a convergence rate of O(1/k^2), where k is the iteration number. Major challenges in the control of the HPV include a nonlinear and l
Power system voltage security assessment is generally applied by considering the power system loadability surface. For a large power system, the loadability surface is a complicated hyper-surface in parameter space, and local approximations are a necessity for any analysis. Unfortunately, inequality constraints due to for example generator overexitation limiters, and higher codimension bifurcation
Lately, much work in the area of voltage stability assessment has been focused on finding post-contingency corrective controls. In this article a contribution to this area will be presented where we search for maximal loadability while considering post-contingency corrective controls. This objective is different from the usual approach to the problem, where the aim is to include the post-contingen
We present exploratory data analysis methods to assess inversion estimates using examples based on l(2)- and l(1)-regularization. These methods can be used to reveal the presence of systematic errors such as bias and discretization effects, or to validate assumptions made on the statistical model used in the analysis. The methods include bounds on the performance of randomized estimators of a larg
This paper examines the potential benefits of applying next best view planning to sequential 3D reconstruction from unordered image sequences. A standard sequential structure-and-motion pipeline is extended with active selection of the order in which cameras are resectioned. To this end, approximate covariance propagation is implemented throughout the system, providing running estimates of the unc
We consider the least-squares (L2) minimization problems in multiple view geometry for triangulation, homography, camera resectioning and structure-and-motion with known rotatation, or known plane. Although optimal algorithms have been given for these problems under an Linfinity cost function, finding optimal least-squares solutions to these problems is difficult, since the cost functions are not
As automatic sensing and information and communication technology get cheaper, building monitoring data becomes easier to obtain. The availability of data leads to new opportunities in the context of energy efficiency in buildings. This paper describes the development and validation of a data-driven grey-box modelling toolbox for buildings. The Python toolbox is based on a Modelica library with th
This chapter describes the architecture of a middleware layer between low-level sensing devices and higher level software layers, to support the requirements of a software infrastructure for networked enterprises. The development of such middleware layer is an important problem, as demonstrated by the number or research papers and the variety of approaches that can be found in literature. The main
We present the first method to handle curvature regularity in region-based image segmentation and inpainting that is independent of initialization. To this end we start from a new formulation of length-based optimization schemes, based on surface continuation constraints, and discuss the connections to existing schemes. The formulation is based on a cell complex and considers basic regions and bou
Semiconductor nanowires are key building blocks for the next generation of light-emitting diodes, solar cells and batteries. To fabricate functional nanowire-based devices on an industrial scale requires an efficient methodology that enables the mass production of nanowires with perfect crystallinity, reproducible and controlled dimensions and material composition, and low cost. So far there have
We construct a variational formulation for the problem of interpolating seismic data in the case of missing traces. We assume that we have derivative information available at the traces. The variational problem is essentially the minimization of the integral over the smallest eigenvalue of the structure tensor associated with the interpolated data. This has the physical meaning of penalizing the l
A one-year study was performed at the Vavihill background station in southern Sweden to estimate the anthropogenic contribution to the carbonaceous aerosol. Weekly samples of the particulate matter PM10 were collected on quartz filters, and the amounts of organic carbon, elemental carbon, radiocarbon (C-14) and levoglucosan were measured. This approach enabled source apportionment of the total car
It has been discussed how important the contributions of informal investors in supporting entrepreneurs and developing startups. The market for informal venture capital is almost invisible source of financing for entrepreneurial ventures, which can explain the difficulty of finding these investors. However, what if the entrepreneur were able to find virgin angel, private individuals who want to un
I denna uppsats undersöks manliga och kvinnliga skillnader inom image, marknadsföring och musik under årtalen 1962-1964. För att göra detta används amerikanska girl groups, exempelvis The Ronettes, och det brittiska bandet The Beatles som referenser och utgör grunden för de analyser som utförs i uppsatsen. Uppsatsens fokus ligger på de såkallade "språk" som bestod av både musikaliska och
Throughout the ongoing pandemic, the operational integrity of the political system of the world has seemingly been on the cusp of collapse, raising questions about the institutional and normative vitality of this system. Moreover, this global moment draws attention to the epistemological conditions that shape global policy frameworks often consulted to devise agendas that address challenges of glo
Justice, in the broadest sense of equality and fairness, is a cornerstone aspect of our abilities, as human beings, to lead individual lives in the way we choose according to what we see as the right or the good way to live. A catalyst for any debate over a theory of justice, Immanuel Kant’s work provides a fundamental basis from which we should begin to understand why society, with justice as a k
Bhutan is the world’s most mountainous country which comes with some logistical difficulties. Due to slow transportation times and lackluster food preservation are the post-harvest losses high which especially affects the rural parts of Bhutan negatively. Solar Food: Reducing post-harvest losses through improved solar drying, is a project set out to design a low-cost solar powered food dryer to im
Hearing is our second most important sense. The main focus of a surveillance camera is obviously the video but the audio shouldn't be neglected. It is possible to hear what the camera can't see and what is said in a conversation can't be showed in a video. Therefore there are good reasons to always try and achieve the best audio possible. This is not an easy task since cameras are oper
