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Improved convergence rate for the simulation of stochastic differential equations driven by subordinated Levy processes

We consider the Euler approximation of stochastic differential equations (SDEs) driven by Levy processes in the case where we cannot simulate the increments of the driving process exactly. In some cases, where the driving process Y is a subordinated stable process, i.e., Y = Z(V) with V a subordinator and Z a stable process, we propose an approximation Y by Z(V-n) where V-n is an approximation of

Assessing water mains condition using hydraulic transients

This paper investigates the potential of using controlled hydraulic transients for non-intrusive assessment of the internal condition of water transmission pipelines. Deterioration of pipelines is a natural process. An effective tool for evaluating the state of pipeline interiors could be extremely useful for planning rehabilitation or identifying critical points in a system. A non-intrusive techn

Invitation to a population-based cohort study: differences between subjects recruited using various strategies.

AIM: The present study compares subjects recruited to a population-based prospective cohort study by community versus personal invitation, and subjects responding late versus early to personal invitation. Subjects were compared with respect to sociodemographic characteristics, selected lifestyle factors, cancer incidence and mortality. METHODS: The Malmö Diet and Cancer Study recruited a total of

Dead-Time Compensation and Performance Monitoring in Process Control

Popular Abstract in Swedish Avhandlingen består av två delar. Den första delen behandlar reglering av processer med lång dödtid. Avhandlingen ger förslag på hur regulatorer för dessa processer ska dimensioneras och jämför sedan prestanda hos dessa regulatorer med vanliga PID-regulatorer. Avhandlingens andra del handlar om metoder för automatisk övervakning av reglerkretsar i processindustrin. TvåThe thesis contains two parts, dead-time compensation and performance monitoring. The first part on dead-time compensation is about robust tuning procedures for dead-time compensating controllers (DTC). Both stable and integrating processes are considered. Simple experiments are performed to obtain process models as well as bounds on the allowable bandwidth for stability. The DTCs used have few pa

Sociala utredningar om barn : En rättssociologisk studie av lagstiftningens krav, utredningarnas argumentationer och konsekvenser för den enskilde

Popular Abstract in Swedish Denna avhandling behandlar sociala utredningar om barn. Avhandlingens övergripande syfte är att ur ett kritiskt perspektiv analysera och diskutera hur de rättsligt givna handlingsdirektiven för utredningsförfarandet och det därmed integrerade stöd- och behandlingsarbetet tillämpas i socialtjänstens faktiska utredningsverksamhet, i förhållande till föräldrarna. Frågan bThis thesis is about the social services’ investigations into childrens need of protection and support. The principal purpose is, from a critical perspective, to analyse and discuss how the legally-accorded procedural directives for the execution of an investigation, and therein the integrated support and counselling work, are adapted in the social services’ actual investigation work in relation t

Variable Valve Actuation in a Spark Ignition Engine - A Flow Field and Heat Release Study

The objective of this thesis was to find ways of improving part-load efficiency for a spark ignition engine by studying the effects of variable-valve actuation on fluid flow and combustion. The in-cylinder flow was measured with laser doppler velocimetry, LDV, and particle image velocimetry, PIV. A piezo-electric pressure transducer was used to measure the in-cylinder pressure, which was used for

Sociologisk essäism – Essäistisk sociologi. Om en tankestils utveckling och aktualitet i en postdisciplinär tid

Contemporary society is characterized by processes of fundamental change (keywords: multiple modernities, globalization, mobilization, individualization, transgression of cultures and identities). At the same time, the production of knowledge undergo swift transition and pluralization. By way of discussing sociology’s history as well as some of its non-scientific interfaces, this article deals wit

Real-time visualisation of fibre networks

Different methods of real-time fibre-network visualisation have been studied. Using an extrusion-based method yields very good results, but for large networks the frame rate becomes unacceptably low. To increase the number of fibres that can be visualised in real time, a textured billboard method has been implemented. With this method, an average performance gain of 60% has been achieved, using an

Low-power voltage-controlled oscillators in 90-nm CMOS using high-quality thin-film postprocessed inductors

Wafer-level packaging (WLP) technology offers novel opportunities for the realization of high-quality on-chip passives needed in RF front-ends. This paper demonstrates a thin-film WLP technology on top of a 90-nm RF CMOS process with one 15-GHz and two low-power 5-GHz voltage-controlled oscillators (VCOs) using a high-quality WLP or above-IC inductor. The 5-GHz VCOs have a power consumption of 0.3

Heavy metal concentrations in European mosses: 2000/2001 survey

The heavy metals in mosses survey was originally established in 1980 as a joint Danish-Swedish initiative under the leadership of Angstromke Ruhling, Sweden and has, since then, been repeated at five-yearly intervals with an increasing number of countries and individuals participating. Twenty-eight European countries, almost 7000 sites and about 100 individuals have been involved in the most recen

Inflammatory indices for chronic bronchitis and chronic obstructive airway disease. Cell populations in bronchial and bronchoalveolar lavage

The development of chronic bronchitis (CB) and chronic obstructive airway disease (COAD) seems to be related to inflammatory changes of airway structure. However, the cause and the exact location and type of these changes resulting in altered airway function are not known. Mucosal inflammation is characterized by the recruitment of granulocytes, macrophages and lymphocytes as well as by the sheddi

THE ROLE OF PHOSPHODIESTERASE 3B IN CAMP-MEDIATED REGULATION OF INSULIN SECRETION

Type 2 diabetes mellitus (T2DM) is characterized by various combinations of ?-cell failure and insulin resistance leading to hyperglycemia and glucose intolerance. In order to maintain glucose tolerance in the insulin resistance state, increased insulin secretion is a requirement and it is because of inadequate islet adaptation that glucose intolerance develops in T2DM. The pathophysiology of T2DM

The effect of nutrient stress on developmental instability in leaves of Acer platanoides (Aceraceae) and Betula pendula (Betulaceae)

Studies of developmental stability can provide insights into the amount of genetic or environmental stress experienced by individuals or populations. In the present study, we used young plants of Acer platanoides (Norway maple) and Betula pendula (silver birch), two distantly related tree species with widely different leaf morphologies, to compare the expression of developmental instability in two

Högpresterande betongs hydratation, struktur och hållfasthet

Syftet med projektet var att jämföra egenskaper hos s k högpresterande betong, d v s betong med mycket låga vattenbindetal (vbt) med motsvarande egenskaper hos normala betongkvaliteter. Studerade egenskaper är hydration, hållfasthetstillväxt och fukttransportegenskaper. I hydrationsstudierna ingår analys av hydratvattenmängd, kemisk krympning och värmeutveckling.