Vakaumus, kerronta, identiteetti

Kirja-arvio

Calculations of Boiling Two-Phase Flow Using a Porous Media Model

Boiling two-phase flow and the equations governing the motion of fluid in two-phase flows are discussed in this thesis. Disposition of the governing equations in three-dimensional complex geometries is considered from the perspective of the porous medium concept. The equations governing motion in two-phase flows were formulated, discretized and implemented in a subroutine for pressure-velocity solution utilizing the SIMPLE algorithm modified for two-phase flow. The subroutine was included in PORFLO, which is a three-dimensional 5-equation porous media model developed at VTT by Jaakko Miettinen. The development of two-phase flow and the resulting void fraction distribution was predicted in a geometry resembling a section of BWR fuel bundle in a couple of test cases using PORFLO.

Technology roadmap for new sales support and management system for crane manufacturing company

Sales configurators are essential tools for companies that offer complicated case specifically crafted products for customers. Most sophisticated of them are able to design an entire end product on the fly according to given constraints, calculate price for the offer and move the order into production. This thesis covers a sales configurator acquisition project in a large industrial company that offers cranes for its customers. The study spans the preliminary stages of a large-scale software purchase project starting from the specification of problem domain and ending up presenting the most viable software solution that fulfils the requirements for the new system. The project consists of mapping usage environment, use cases, and collecting requirements that are expected from the new system. The collected requirements involve fitting the new sales system into enterprise application infrastructure, mitigating the risks involved in the project and specifying new features to the application whilst preserving all of the admired features of the old sales system currently used in the company. The collected requirements were presented to a number of different sales software vendors who were asked to provide solution suggestions that would fulfil all the demands. All of the received solution proposals were exposed to an evaluation to determine the most feasible solutions, and the construction of evaluation criteria itself was a part of the study. The final outcome of this study is a short-list of the most feasible sales configurator solutions together with a description of how software purchase process in large enterprises work, and which aspects should be paid attention in large projects of similar kind.

Ikäkaudet

Teemanumero 2008.

Ikä on aliteoretisoitu ero

Saatteeksi

Mittatilausetiikkaa folkloristeille

Kirjallisuusarvostelu

Puettu ja riisuttu valta

Kirjallisuusarvostelu

Turismin kulttuuripeliä Ahvenanmaalla

Kirjallisuusarvostelu

Itävallan ja Unkarin monidimensioinen rajakiista

Kirjallisuusarvostelu

Holocene Varved Lake Sediments as Records of Palaeoenvironmental Change and Geomagnetic Palaeosecular Variation in Eastern Finland

This dissertation discusses Holocene palaeoenvironmental and palaeomagnetic secular variation (PSV) records reconstructed from sediments preserved in Lake Lehmilampi (63º37´N, 29º06´E) and Lake Kortejärvi (63º37´N, 28º56´E) in eastern Finland. Several piston and freeze cores were obtained from both lakes for varve and magnetic analyses. Sediment samples were impregnated in low-viscosity epoxy and physical parameters of varves, including varve thickness and relative grey-scale values, were recorded using x-ray densitometry combined with semiautomatic digital image analysis. On average, varve records of Lehmilampi and Kortejärvi cover 5122 and 3902 years, respectively. Past solar activity, as estimated by residual ₁₄C data, compares favourably with varve thicknesses from Lehmilampi during the last 2000 years. This indicates the potential of clastic-organic varves to record sensitively climatic variations. Bulk magnetic parameters, including magnetic susceptibility together with natural, anhysteretic and isothermal remanent magnetizations, were measured to describe mineral magnetic properties and geomagnetic palaeosecular variation recorded in the sediments. Main stages in the development of the investigated lakes are reflected in the variations in the mineral magnetic records, sediment lithology and composition. Similar variations in magnetic parameters and sediment organic matter suggest contribution of bacterial magnetite in the magnetic assemblages of Lehmilampi. Inclination and relative declination records yielded largely consistent results, attesting to the great potential of these sediments to preserve directional palaeosecular variation in high resolution. The PSV data from Lehmilampi and Kortejärvi were stacked into North Karelian PSV stack, which may be used for dating homogenous lake sediments in the same regional context. Reconstructed millennial variations in relative palaeointensity results are approximately in agreement with those seen in the absolute palaeointensity data from Europe. Centennial variations in the relative palaeointensity, however, are influenced by environmental changes. Caution is recommended when using varved lake sediments in reconstructing relative palaeointensity.

Karjalan muisti

Kirja-arvio