This paper considers the problem of stability of linear feedback systems with time-varying but bounded delays. Simple but powerful criteria of stability, as well as a simple performance bound, are presented for both continuous-time and discrete-time systems. Using these criteria, stability can be checked in a closed loop Bode plot. This makes it easy to design the system for robustness.

The first aim of this doctoral work has been to develop a new generation of computer programs for transient and steady-state heat conduction in two and three dimensions. A large range of heat transfer problems within the field of buildings physics can be analyzed using these tools. There are, however, many things to keep in mind when modelling a problem, such as how to choose the numerical mesh,

Human neuroblastoma cells SH-SY5Y and neuroblastoma-glioma cells NG 108-15 have been used as models for the elucidation of the effects of ethanol on receptor-mediated phospholipase C activity, c-fos mRNA expression and protein kinase C activity. Cells were exposed to ethanol (0-200 mM) for varying periods up to seven days. Agonist stimulated events were obtained in NG 108-15 cells with bradykinin

Aim: To investigate the association between the use of cellular or cordless telephones and the risk for salivary gland tumours. Methods: Cases were assessed from the six regional cancer registries in Sweden. Four controls matched for sex and age in five year age groups were selected for each case. A total of 293 living cases and 1172 controls were included. Results: There were 267 (91%) participat

BACKGROUND AND PURPOSE: The purpose of this study was to determine whether preoperative and postoperative enrichment of the environment can enhance the functional outcome after cerebral infarction in rats. METHODS: The right middle cerebral artery was ligated in adult spontaneously hypertensive male rats, and the functional outcome was studied for 12 weeks after the operation. Three groups were co

Popular Abstract in Swedish Programvara spelar en allt viktigare roll i industriella produkter. Bilar, flygplan, telefoner, hemelektronik, kärnkraftverk m.m. innehåller alla programvara. När man utvecklar programvara blir det ofta fel i produkterna, fel som kan vara mycket allvarliga för funktion och säkerhet. Ett första steg i att minska dessa fel är att uppskatta hur många fel som finns i produkIn software engineering, the quality of software and in particular the software reliability has to be controlled and improved. Hence there is a need for measuring and controlling the number and appearance of software faults and failures. This thesis presents models for estimation of residual faults after inspections and a model for usage specifications which enables estimation of operational failu

We demonstrate that the multiple gluon emission phase space in the dipole cascade model has a strong linear correlation with the number of gluons emitted. The number of gluons per unit available phase space at a certain resolution scale is found to be remarkably independent of the cms energy and global event properties like thrust, and even changes in the ordering variable or resolution scale. We

The fer gene from Bacillus subtilis has been subcloned and overexpressed in Escherichia coli and the protein (Fer) purified to homogeneity. N-Terminal sequencing and mass spectrometry indicate that the initiator methionine is removed from the protein and that the molecular mass is 8732 Da consistent with that deduced from the gene sequence. Amino-acid sequence comparisons indicate that Fer is a fe

Properties of nonionic triblock copolymers of poly(ethylene oxide) (PEO) and poly(propylene oxide) (PPO) (EOnPOmEOn) in aqueous solution and their interaction with the ionic surfactants sodium dodecyl sulfate and hexadecyltrimethylammonium chloride have been investigated by static and dynamic light scattering, high sensitivity differential scanning, and isothermal titration calorimetry. The studie

Objective. Intrauterine growth restriction ( IUGR) resulting in low birth weight for gestational age may predispose one to development of cardiovascular disease later in life. Abnormal fetal blood flow in the presence of fetal growth restriction helps to distinguish infants with true fetal growth impairment from small but normal infants. Our goal was to investigate associations between IUGR with a

The purpose was to examine the long-term stability of a diagnosis of psychotic disorder in adolescence and to focus on diagnostic change over time. A total of 88 patients with a first episode of early onset psychosis (before 19 years) were followed up an average of 10.5 years (range 5.1-18.2) after admission. This report includes the 68 patients who could be traced and interviewed with the Positiv

A carbohydrate binding module, CBM4-2, derived front the xylanase (Xyn 10A) of Rhodothermus marinus has been used as a scaffold for molecular diversification. Its binding specificity has been evolved to recognise a quite different target, a human monoclonal IgG4. In order to understand the basis for this drastic change in specificity we have further investigated the target recognition of the IgG4-

This tutorial describes experiences with applying a control theoretical approach to achieving performance guarantees in Web servers, with emphasis on delay control. A model for the server is formulated and translated into a control problem formulation. Limitations of the control theoretic approach are identified that arise due to system non-linearities and modeling inaccuracies. Solutions are prop