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Popular Abstract in Swedish Kemisk industri, inklusive petrokemisk industri, är en av de största av alla världens industrier. Mer än 60% av de produkter som framställs och 90% av de processer som används inom kemisk industri är baserade på katalys. Det är tydligt att katalytiska processer utgör en mycket viktig del av ett antal av de största industrierna och att stura ekonomiska vinningar därför kSynthesis and characterization of new transition metal carbonyl clusters has been undertaken, and evaluation of the new clusters to act as catalysts/catalysts precursor in asymmetric reactions has been carried out. The catalytic hydrogenation of tiglic acid under relatively mild conditions, using diastereomeric clusters of the general formula [(µ-H)2Ru3(µ3-S)(CO)7(µ-1,2-L)] (L= chiral diphosphine

The development of electrical resistivity imaging techniques has been rapid in the last decade. This applies to data acquisition as well as inverse modelling techniques, and has lead to a greatly expanded practical applicability of the method. A trend today is to move from traditionally used electrode array types towards non-conventional arrays that are more efficient for multi-electrode equipment

Experiments relying on tomographic reconstruction of soot emission and absorption offer relatively simple and inexpensive ways to image both soot concentration and temperature in axisymmetric flames. Because the tomography problem is mathematically ill-posed, however, special measures have to be taken to ensure an accurate solution. This paper describes the application of one such measure, Tikhono

This article presents two types of advanced heat exchangers: high-temperature heat exchangers (HTHEs) and compact heat exchangers (CHEs). Design materials selection and coolants for high temperatures are described. As a promising HTHE and a CHE, printed circuit heat exchanger has been outlined. Micro/mini-channel heat exchanger and foam heat exchanger, as two types of CHEs, are also described. Var

We examine consumer certainty of future preferences and overconfidence in predicting future preferences. We explore how preference certainty and overconfidence impact the option value to revise today’s decisions in the future. We design a laboratory experiment that creates a controlled choice environment, in which a subject's choice set (over food snacks) is known and constant over time, and the t

Block transmission over noisy communication channels is characterized by two performance criteria: the bit error probability P/sub b/ and the block error probability P/sub B/. If P/sub B/ goes to zero when N/spl rarr//spl infin/ (where N denotes the length of the permutors), P/sub b/ also must go to zero for all symbols in the block but, in general, the reverse is not true. Therefore we formulate

Elasticity and damping are significant properties of rubber, taken advantage of in engineering applications. It is therefore important that the constitutive model accurately captures these aspects of the mechanical behavior. In the first part of the thesis a description of theory and experiments for determination of hyperelastic parameters required for finite element analysis is provided. Test sp

Chromosomal aberrations in solid tumors appear in complex patterns. It is important to understand how these patterns develop, the dynamics of the process, the temporal or even causal order between aberrations, and the involved pathways. Here we present network models for chromosomal aberrations and algorithms for training models based on observed data. Our models are generative probabilistic model

The effects of high optical depth phenomena, such as superradiance, are investigated in potential quantum memory materials. The results may have relevance for several schemes, including controlled reversible inhomogeneous broadening, atomic frequency combs, and quantum memories based on electromagnetically induced transparency, which are based on using ensembles as storage media. It is shown that

Popular Abstract in Swedish Modellering och simulering är etablerade tekniker för att lösa designproblem inom många olika ingenjörsdiscipliner idag. Dedicerade språk, såsom Modelica, och effektiva mjukvaror finns också tillgängliga. I denna avhandling presenteras en språklig utvidgning av Modelica, Optimica, som är avsedd för formulering av dynamiska optimeringsproblem. För att demonstrera användnModeling and simulation are established techniques for solving design problems in a wide range of engineering disciplines today. Dedicated computer languages, such as Modelica, and efficient software tools are available. In this thesis, an extension of Modelica, Optimica, targeted at dynamic optimization of Modelica models is proposed. In order to demonstrate the Optimica extension, supporting sof

This thesis regards datapath design and analysis at several abstraction levels. Five papers are presented that focus on datapath design for mobile communication systems and design methodologies for such datapaths. Paper I discusses different aspects of Turbo channel decoder design for high speed and low power applications. It is shown that critical path delay is significantly reduced by simple re

The spectral properties of financial correlation matrices can show features known from completely random matrices. A major reason is noise originating from the finite lengths of the financial time series used to compute the correlation matrix elements. In recent years, various methods have been proposed to reduce this noise, i.e. to clean the correlation matrices. This is of direct practical relev

The development of treatment planning methods in radiation therapy requires dose calculation methods that are both accurate and general enough to provide a dose per unit monitor setting for a broad variety of fields and beam modifiers. The purpose of this work was to develop models for calculation of scatter and transmission for photon beam attenuators such as compensating filters, wedges, and blo

We propose a test resource partitioning and optimization technique for core-based designs. Our technique includes test set selection and test resource floor-planning with the aim of minimizing the total test application time and the routing of the added TAM (test access mechanism) wires. A feature of our approach is that it pinpoints bottlenecks that are likely to limit the test solution, which is

Silicon microtechnology has been used to develop a microstructure toolbox in order to enable high accuracy protein identification. During the last 2 years we developed and applied monocrystalline silicon structures and established new automated protein analysis platforms, The development of a high throughput protein platform is presented where fully automated protein identifications are performed.

Popular Abstract in Swedish Avhandlingen handlar om tes av periodicitet och trend inom långminne-processer. Med hjälp av diskret wavelet transform och periodogram presenteras vi två test för periodicitet och tre test för trend. Vi utvärderar vår test samt studerar deras egenskaper delvis genom att använda oss av datorintensiva metoder såsom Monte Carlo och delvis genom att jämföra dem med andra liThis thesis presents methods of testing the periodicity and trend for the time series, which exhibit dependence over long periods of time. Many such processes can be modeled by a class of models called fractionally differenced processes. The first approach we consider to analyse such processes is by using the band periodogram, which divides the periodogram into different intervals or bands, matchi

Software architecture, the underlying structure to a software system, is an asset which can be invested in. Such investments can later be capitalized on in the form of e.g. increased flexibility and enhanced maintainability. These benefits may be gained in a system developed in one project, but are much more visible in a strategic perspective when several projects share resources. Architectural de

This paper gives an overview of the present knowledge regarding the interaction between the climatic conditions at the concrete surface and the corresponding conditions inside the concrete. The phenomena dealt with are those involved in frost damage, frost and salt scaling and reinforcement corrosion, such as temperature and moisture conditions in the near surface regions, carbonation and chloride

Symptoms and signs of the urogenital estrogen deficiency syndrome occur relatively late in a women's life when endogenous estrogen levels are well below those required to stimulate endometrial growth. At age 60 and above symptoms are common and progress with advancing age. The first and most common complaint is vaginal dryness, but symptoms of lost control of micturition as well as urge incontinen