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Optoelectric spin injection in semiconductor heterostructures without a ferromagnet

We have shown that electron-spin density can be generated by a dc current flowing across a pn junction with an embedded asymmetric quantum well. Spin polarization is created in the quantum well by radiative electron-hole recombination when the conduction electron momentum distribution is shifted with respect to the momentum distribution of holes in the spin-split valence subbands. Spin current app

A Near-Infrared Transient Absorption Study of the Excited-State Dynamics of the Carotenoid Spirilloxanthin in Solution and in the LH1 Complex of Rhodospirillum rubrum.

The spectroscopic properties of spirilloxanthin in an nhexane solution and bound to the core light-harvesting LH1) complex of Rhodospirillum rubrum were studied by near infrared ultrafast transient absorption spectroscopy. Global analysis of the kinetic traces measured after excitation of spirilloxanthin to the S2 (1Bu +) state enabled us to estimate the species-associated difference spectra that

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