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Protection of systems with series compensated lines is considered to be one of the most difficult tasks for relay manufacturers and utility engineers. Protection and control of surrounding circuit elements, particularly transmission line protection, needs to be adapted to the variations introduced by these devices. Fixed series capacitors and thyristor controlled devices introduce harmonics and no

In this paper, the inverse scattering problem of amultilayer structure is analysed with the Fisher information matrix and the Cramer-Rao lower bound (CRLB). The CRLB quantifies the ill-posedness of the inverse scattering problem in terms of resolution versus estimation accuracy based on the observation of noisy data. The limit for feasible inversion is identified by an asymptotic eigenvalue analys

Solutions to non-linear least squares problems play an essential role in structure and motion problems in computer vision. The predominant approach for solving these problems is a Newton like scheme which uses the: hessian of the function to iteratively find a, local solution. Although fast, this strategy inevitably leeds to issues with poor local minima, and missed global minima. In this paper ra

This study was designed to investigate suicide attempters' views on problems underlying their suicidal behavior. A questionnaire comprising 17 problems was presented to 54 non-consecutive patients (men/women=25/29, mean age 36 ±14 years) admitted to a specialized psychiatric ward following an attempt. (In the large majority of cases the method was self-poisoning. 37% had previously attempted suici

Several different strategies are effective for medical treatment of motor problems in Parkinson's disease (PD). Many guidelines and evidence-based reviews are available, but there is no documentation or consensus in favor of just one treatment strategy. This review presents two algorithms that may be helpful when deciding how to treat a PD patient at various stages of the disease. The first algori

Finding optimal routes and spectrum allocation in flexgrid optical networks, known as the RSA problem, is an important design problem in transport communication networks. The problem is NP -hard, and its intractability becomes profound when network instances with several tens of nodes and several hundreds of demands are to be solved to optimum. In order to deal with such instances, large-scale opt

The numerical treatment of two-dimensional scattering in inhomogeneous media is considered. A novel approach in treating convolution operators with low regularity is used to construct an iterative solver for the Lippmann-Schwinger integral equation. In this way, accurate approximations within a choice of bandwidth can be obtained in a rapid manner. The performance of the method is tested on a disc

Popular Abstract in Swedish I denna avhandling behandlas två delvis överlappande teman; inversa problem av tomografisk karaktär samt snabba och noggranna metoder för applicering av faltningsoperatorer. Inom det första temat så studeras det inversa problemet inom Dopplertomografi och för detta ändamål så introduceras Dopplermomenttransformen. Genom att undersöka egenskaperna hos denna transform såThere are two, partially interlaced, themes treated in this thesis; inverse problems of tomographic type and fast and accurate methods for the application of convolution operators. Regarding the first theme, the inverse problem of Doppler tomography is considered and the Doppler moment transform is introduced for that purpose. By investigating the properties of the transform, we prove results reg

The authors consider the following inverse problem for scattering of time-harmonic waves by an impenetrable obstacle. Given data obtained from the scattered field at infinity, they determine the location of the boundary of the obstacle. To solve the forward scattering problem, they use the T matrix method, or null field approach. The ill-posedness of the inverse problem is discussed. To solve the

Lower system temperatures in district heating (DH) grids are important factors for system efficiency. Lower system temperatures lead, for example, to lower heat losses and higher production unit efficiency. One obstacle to lower supply temperatures are so-called bottlenecks in DH networks. Bottlenecks are areas in DH networks of very low differential pressure, which makes it difficult to supply th

A novel modified method for obtaining approximate solutions to difficult optimization problems within the neural network paradigm is presented. We consider the graph partition and the travelling salesman problems. The key new ingredient is a reduction of solution space by one dimension by using graded neurons, thereby avoiding the destructive redundancy that has plagued these problems when using s

Gaza has several water problems; inefficient water use by the agricultural sector, limited fresh water supply and high water demand, groundwater contamination, seawater intrusion and shortage of electricity. More water and electricity for the future development of Gaza that will give better life; a significant value of water should be added to the Palestinians living in blocked Gaza; more employme