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Analysis of an Extremal Controller for Hammerstein Models

The ordinary differential equations given by Ljung(1977) are used to analyse the behaviour of a certain adaptive extremal controller. It is shown that this controller will usually converge to the wrong point.This work was supported by the Swedish Board for Technical Development under contract No. 76-3804.

Post-industrial division of labour as a systemic barrier for immigrants in the Swedish labour market

ABSTRACT. Differences in labour force participation and unemployment rates between indigenous populations and immigrants are common throughout Europe. But the gap seems to be particularly wide in Sweden. Based on studies of work places that traditionally employed large numbers of immigrants, but where they are now declining, it is argued that a driving force behind this process of exclusion is to

Interactions between Sulfide Minerals and Alkylxanthate Ions .4. Vibrational Spectroscopic and Calorimetric Study of the Interactions between Galena and Synthetic Lead(Ii) Sulfide, and Alkylxanthate Ions in Aqueous, Acetone and Acetonitrile Solutions

The reactions between galena and synthetic lead(II) sulphide powders, and potassium alkylxanthates have been studied in aqueous, acetone and acetonitrile solutions. Acetone and acetonitrile have been used since potassium and lead(II) alkylxanthates are soluble in these solvents. Qualitative analysis of the alkylxanthate species present on the surfaces of galena and synthetic lead(II) sulphide afte

Technical discussion I - Underwater light measurement and light absorption by algae

In this paper concepts and nomenclature of light measurements are discussed. The particular problems of underwater light measurements and the calibration of the equipment were presented. The pros and cons with spectroradiometers and broad band sensors were discussed. The use of specific ultraviolet-B sources for algal photobiology is recommended.

O2 consumption, aerobic glycolysis and tissue phosphagen content during activation of the Na+/K+ pump in rat portal vein

Oxygen consumption, lactate production and tissue contents of ATP, phosphocreatine (PCr) and lactate were measured following readdition of K+ to K+-depleted rat portal veins, in order to study the energy turnover associated with Na+/K+ pumping. During incubation in K+-free medium at 37 degrees C spontaneous contractions disappeared in 10-20 min. Readdition of K+ (5.9 mM) after 40 min K+-free incub

Reswelling of polyelectrolyte hydrogels by oppositely charged surfactants

The interactions between charged alkylacrylamide gels of varying hydrophobicity and charge density and the oppositely charged surfactant hexadecyltrimethylammonium (C(16)TA(+)) have been investigated to determine the conditions necessary to induce excess surfactant binding (beyond charge neutralization) and resolubilization of the polymer-surfactant complex. In all cases, an initial gel collapse o

Two new species of Caloplaca (Teloschistaceae) from the southern hemisphere

Caloplaca gyalectoides S. Kondratyuk & Karnefelt from the Cape Province, South Africa, and Caloplaca chilensis S. Kondratyuk, Karnefelt, Froden & Arup with an associated parasymbiont Arthonia tetraspora S. Kondratyuk & Karnefelt occurring mainly along the coast in central Chile are described as new. Possible associated taxa are briefly discussed. Distribution maps are provided for all

High coloration performance of electrochromic devices assembled with electrolytes based on a branched boronate ester polymer and lithium perchlorate salt

An amorphous, colorless, and highly transparent polymer containing boron atoms in its branched chain architecture was synthesised from boron trioxide, poly(ethylene glycol) (PEG) and methoxy end-capped PEG. Electrolytes based on this polymer and different concentrations of lithium perchlorate (LiClO4) were prepared and characterised by impedance spectroscopy, calorimetry and thermogravimetry. The

Influence of laser phase and frequency fluctuations on photon-echo data erasure

Erasure of data stored by use of photon echoes has been investigated as a function of data writing time and data storage time. The results clarify the requirements on laser phase and frequency stability for performing photon-echo data erasure. The analysis of phase and frequency stability of a light source by the photon-echo erasure process is illustrated. A theoretical analysis emphasizing the ph

High resolution banding analysis of the reciprocal translocation t(6;9) in acute nonlymphocytic leukemia

The cytogenetic, hematologic, and clinical characteristics of a 13-year-old girl with acquired t(6;9)(p23;q34) and dysmyelopoietic syndrome developing into acute myelomonocytic leukemia are described, bringing the total number of patients with t(6;9) and hematologic disease described in the literature up to 19. The diagnosis has been acute myeloid leukemia in the great majority of these patients;

Metabolic correlates to pacemaker activity in the smooth muscle of guinea-pig mesotubarium

Oxygen consumption (FO2) and lactate production (Flac) were measured during spontaneous activity in the guinea-pig mesotubarium. During spontaneous contractions FO2 increased to maximally 0.270 +/- 0.025 mumol min-1g-1 (n = 23), followed by a rapid fall immediately upon relaxation. In the relaxed period (5-15 min) between spontaneous contractions FO2 continued to slowly decrease by about 25% towar

Pain and fractures are independently related to lower walking speed and grip strength: Results from the population study "Good Ageing in Skåne".

Background Earlier reports on reduced physical performance and osteoporosis-related fractures have mostly been short-term studies. The aim of this investigation was to examine the effects of fractures on physical functioning 3 years after trauma, the latter being stratified for pain. Participants and methods The study consisted of a population-based case-control study including 289 subjects from t

Universal scaling of the rapidity dependent elliptic flow and the perfect fluid at RHIC

The pseudo-rapidity dependence of the elliptic flow at various excitation energies measured by the PHOBOS Collaboration in Au+Au collisions at RHIC is one of the surprising results that has not been explained before in terms of hydrodynamical models. Here we show that these data are in agreement with theoretical predictions based on perfect fluid hydrodynamics. We also show that these PHOBOS data

Differential polyamine analogue effects in four human breast cancer cell lines

Polyamine analogues have demonstrated anti-tumour activity in a number of solid tumour models. In the present study we compared the cytotoxicities of three polyamine analogues against four breast cancer cell lines. All cell lines are derived from tumours of women with breast cancer and, although we are sampling just a small number of tumours, they represent a spectrum of the genetic plethora of br

Dual-pump dual-broadband coherent anti-Stokes Raman scattering in reacting flows

A dual-pump, dual-broadband coherent anti-Stokes Raman scattering system for simultaneous measurements of temperature and concentrations of N-2, O-2, and CO2 in reacting flows is demonstrated. In this system pure rotational transitions of N-2-O-2 and rovibrational transitions of N-2-CO2 are probed simultaneously with two narrowband pump beams, a broadband pump beam, and a broadband Stokes beam. Th