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System identification of linear multivariable dy-namic models based on discrete-time data can be performed using a algorithm combining linear regression and LQG-balanced model reduction. The approach is applicable also to unstable system dynamics and it provides balanced models for optimal linear prediction and control.

Computer simulations were used to study the effect of a single reinforcement fiber added to a mechanical fibre network. The stresses of the surrounding fibers and inter-fiber bonds increased proportionally to the logarithm of the elastic stiffness of the reinforcement fibre. In the case of fiber failure the breaking stress of the model system increased only little and breaking strain decreased lit

We present a new type of nanometer-scale semiconductor nonlinear device, called self-switching device (SSD). The device was realized by simply etching insulating grooves into a semiconductor, between which a narrow channel with a broken symmetry was formed. Because of the asymmetry in the channel boundary, an applied voltage V not only changes the potential profile along the channel direction, but

A neural model with N interacting neurons is considered. A firing of neuron i delays the firing times of all other neurons by the same random variable theta((i)), and in isolation the firings of the neuron occur according to a renewal process with generic interarrival time Y-(i). The stationary distribution of the N-vector of inhibitions at a firing time is computed, and involves waiting distribut

In this study, a three-dimensional calculation method has been developed to simulate and analyze steam reforming of natural gas, and the effects on various transport processes in a duct from a compact steam reformer. The reformer conditions such as the combined thermal boundary conditions on solid walls, mass balances associated with the reforming reactions and gas permeation to/from the porous ca

Eukaryotic cells contain numerous compartments, which have different protein constituents. Proteins are typically directed to compartments by short peptide sequences that act as targeting signals. Translocation to the proper compartment allows a protein to form the necessary interactions with its partners and take part in biological networks such as signalling and metabolic pathways. If a protein

House dusts, collected for detection of microorganisms in buildings, sometimes have to be stored before measurement. It is possible that continued growth of microorganisms in the stored samples will increase the levels of CFU, chemical marker, biomass etc. The aim of this investigation was to assess the influence of relative humidity on microbial growth in dust samples. We have exposed dust sample

Even though multisensory environments (MSE) incorporate artifacts and technology to provide sensory stimuli, most of these artifacts are non-interactive. Twenty-four children with profound developmental disabilities from three MSE institutions have been involved in a research study. A handful of interactive design artifacts, which have been developed as a tool for ideation and to enhance the use o

One problem with web servers is that they are sensitive to overload. The servers may become overloaded during temporary traffic peaks when more requests arrive than the server is designed for. Because overload usually occurs rather seldom, it is not economical to overprovision the servers for these traffic peaks, instead admission control mechanisms can be implemented in the servers. This pa per i

Success factors are identified for residential fires. Success factors are defined as aspects resulting in a positive outcome if a fire occurs in a home environment. The factors could be linked to the individual persons as well as to the society. The success factors have been identified using cluster analysis of statistical information and using interviews with rescue services personnel. The typica

Deterministic lateral displacement (DLD) is a powerful bimodal separation scheme [1] based on fluid flow through regular obstacle arrays that in its basic embodiment sends suspended particles in two different directions as a function of size. We show that without the need to seal devices and without the need for fluidic connections or pumps, particle separation can be achieved by the passive flow

Deterministic lateral displacement (DLD) is a powerful bimodal separation scheme [1] based on regular obstacle arrays that in its basic embodiment sends particles in two different directions as a function of size. We add functionality to the technique by including gravitational forces, as a perturbation to particles transported by fluid flow, and as a way of transporting the particles through a st

Conventional fractionation techniques fail to fully benefit from the variety in morphology and shape that is found among biological particles. Although light scattering in conventional FACS gives some information on the size and morphology of a particle, it is generally not capable of giving a definite number on specified dimensions of a small object. We demonstrate an approach where we select whi

A new numerical model of regional sediment transport and barrier elongation, supplied by sediment coming from longshore sediment transport (LST), was developed. The spit growth and barrier elongation model was based on the model proposed by Kraus (1999). The LST rate used as input for the spit growth and barrier elongation model was simulated by the one-line model of shoreline change (Hanson, 1987