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The maximum likelihood method of identification is a powerful tool for obtaining mathematical models of dynamic processes. To apply this method a loss function has to be minimized. The aim of the paper is an investigation of the local minimum points of this loss function for a common structure of a general form. If the loss function has more than one local minimum point, numerical problems can occ

Study design:Register study.Objectives:To design and implement a validation process to check the completeness of the Hospital Discharge Register (HDR) held by the Swedish National Board of Health and Welfare.Setting:Sweden.Methods:An accurate traumatic spinal cord injury prevalence group (n=495) was acquired from the Swedish Spinalis Clinic. A register control was performed on the group by raising

The problem of estimating a spectral representation of damped sinusoidal signals from a gapped data set is of considerable interest in several applications. In this paper, we propose a filterbank approach to provide such an estimate, by first reconstructing the missing data samples assuming that the spectral content of the missing data is similar to that of the available samples, and then forming

The nature of size fluctuations is crucial in forecasting future population persistence, independently of whether the variability stems from external forces or from the dynamics of the population renewal process. The risk of intercepting zero is highly dependent on the way the variance of the population size relates to its mean. The minimum population size required for a population not to go extin

The evolution of partial migration in birds is typically assumed to be the result of an optimization process. The fitness rewards for individuals choosing to migrate are balanced against the rewards of remaining in the breeding area all year around. This balancing is often thought to result in an evolutionarily stable strategy (ESS) such that an optimal fraction of the population becomes migratory

The secondary motion induced by flow through curves and bifurcations has been subject to investigation over long time due to its importance in physiological and technological applications. In contrast to the flow in a straight pipe, curvature leads to the formation of secondary flow which is often unsteady. Streamline curvature occurs also in bifurcating pipes leading to some corresponding seconda

We consider algorithms for simulation of iterated Itô integrals with application to simulation of stochastic differential equations. The fact that the iterated Itô integral I_{ij}(t_n,t_n+h)=\int_{t_n}^{t_n+h} \int_{t_n}^{s} dW_{i}(u)dW_{j}(s) conditioned on W_i(t_n+h)-W_i(t_n) and W_j(t_n+h)-W_j(t_n), has an infinitely divisible distribution is utilised for the simultaneous simulation of $I_{ij}(

We report on the final electroweak measurements performed with data taken at the Z resonance by the experiments operating at the electron-positron colliders SLC and LEP. The data consist of 17 million Z decays accumulated by the ALEPH, DELPHI, L3 and OPAL experiments at LEP, and 600 thousand Z decays by the SLID experiment using a polarised beam at SLC. The measurements include cross-sections, for

This work discusses methods to obtain reference following on unstable systems. The task is critical; introduction of refernce signal might cause instability in some cases. It is thus interesting to develop strategies that offer acceptable reference following, but also guarantees stability. In practice similiar problems arises in flight control systems for unstable fighter aircrafts. Experimental v

A theoretical investigation of the stresses in external involute helical gears has been carried out. Geometrical conditions are given and the load distribution along and between the gear teeth in contact is calculated. With this load distribution, contact pressure and fillet tensile and compression stresses are calculated. The influence bending functions, used to calculate the load distribution, a

Popular Abstract in Swedish Reglering av celltillväxt och celldöd är mycket viktigt för bibehållandet av balansen mellan antalet olika celler i kroppen. Om regleringen rubbas kan olika sjukdomar uppkomma, som karakteriseras av för mycket celltillväxt eller av för mycket celldöd. Exempel är cancer, där man har för mycket tillväxt, samt många degenerativa sjukdomar som diabetes, Parkinsons och aids,Apoptosis is a kind of death that is best described as cellular suicide and it is important for normal tissue homeostasis. The process can be induced by a number of different stimuli and the dying cell goes through a defined pathway terminating in typical biochemical and morphological alterations of the cell. With my studies I wanted to investigate the role of the polyamines in the regulation of a

A permutor (interleaver) design method was proposed to show the existence of turbo codes with minimum distance growing logarithmically with the permutor length. It was found that the minimum distance of a turbo code depended on the structure of the permutor or on its life cycle structures. It was demonstrated that the method could be used for the construction of turbo codes with practical blocklen

Thermographic phosphors can be robust temperature remote sensors. The accuracy of the temperature measured by the phosphor is highly dependent on the quality of the phosphor calibration used. Conventionally, thermographic phosphors are calibrated by measuring a series of decay curves at known stable oven temperatures. The process is then repeated covering the thermal sensitivity range of the phosp

Due to the increasing usage of embedded instruments in many electronic devices, new solutions to effectively access these instruments appeared, including the new IEEE 1687 standard. The approach supported by IEEE 1687 allows a flexible access to embedded instruments through the Boundary Scan interface. The IEEE 1687 network includes a set of reconfigurable scan chains. This paper addresses the iss