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The role of young-of-the-year fish in lake ecosystems

Popular Abstract in Swedish Min avhandling handlar om vilken roll fiskyngel har i samspelet mellan olika organismer i våra sjöar, såsom i samspelet mellan rovfiskar, djurplanktonätande fiskar, djurplankton och alger. Fisklarver och fiskyngel förekommer i stora mängder i våra sjöar under sommaren. Varje vår/sommar kläcks nya kullar av bl.a. abborre och mörtlarver, vilka äter (prederar på) små djurFood chain theory is based on consumption; that is, presupposing that the only important interaction between organisms is that they actually meet in an unstructured environment and that one of them is consumed. Recently, studies, including biomanipulation projects, have indicated that trophic interactions are more complex than predicted by food chain theory. In this thesis I examine the role of yo

A CMOS implementation of a video-rate successive approximation A/D converter

Previous approaches to video-rate CMOS A/D (analog-to-digital) converters are based on fully-parallel, subrange, or pipeline architectures. The authors describe a 5-MHz 8-bit experimental design of a successive-approximation A/D converter using 3-μm CMOS technology. Since neither capacitors nor a resistor string are needed in the current-switching technique, a conventional digital technology can b

V-GQM: a feed-back approach to validation of a GQM study

The Goal/Question/Metric paradigm is used for empirical studies on software projects. Support is given on how to define and execute a study. However, the support for running several subsequent studies is poor. V-GQM introduces a life-cycle perspective, creating a process, spanning several GQM studies. After the GQM study has been completed, an analysis step of the plan is initiated. The metrics ar

Manual Control and Stabilization of an Inverted Pendulum

The problem of stabilizing an inverted pendulum on a cart while enabling manual control of the cart velocity is treated. Introduction of an input saturation nonlinearity makes the problem challenging in the sense that the system may be driven to a state where recovery is not possible. A controller based on the controllability set of the inverted pendulum, which ensures stability and tracking of co

A higher-order singularity subtraction technique for the discretization of singular integral operators on curved surfaces

This note is about promoting singularity subtraction as a helpful tool in the discretization of singular integral operators on curved surfaces. Singular and nearly singular kernels are expanded in series whose terms are integrated on parametrically rectangular regions using high-order product integration, thereby reducing the need for spatial adaptivity and precomputed weights. A simple scheme is

Clonal structure and reproductive biology in the gynodioecious herb Glechoma hederacea L. Lamiaceae

Clonal structure and reproductive biology in the gynodioecious herb Glechoma hederacea L. Lamiaceae The frequencies of females, hermaphrodites and partially male-sterile (PMS) genets of Glechoma hederacea were estimated in natural populations in S Sweden. The frequency of females and PMS genets in natural populations varied from 0 to 100%. The temporal and spatial variation in stamen fertility in

Till främmande land

Swedish travellers during 19th century through the eyes the artist Egron Lundgren.

Dynamic characterization of elastomers using impact testing

Dynamic characterization of elastomers, i.e. laboratory testing and fitting of constitutive models, is quite complicated. The demands on the laboratory equipment and the skill of the personal handling the test equipment are high. Stationary harmonic testing is an established method for evaluating dynamic properties of elastomers. However, it is demanding experimentally when it comes to high freque