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Flow and Temperature Distribution in an Experimental Engine: LES Studies and Thermographic Imaging

Temperature stratification plays an important role in HCCI combustion. The onsets of auto-ignition and combustion duration are sensitive to the temperature field in the engine cylinder. Numerical simulations of HCCI engine combustion are affected by the use of wall boundary conditions, especially the temperature condition at the cylinder and piston walls. This paper reports on numerical studies an

Turbulence and combustion interaction: High resolution local flame front structure visualization using simultaneous single-shot PLIF imaging of CH, OH, and CH2O in a piloted premixed jet flame

High resolution planar laser-induced fluorescence (PLIF) was applied to investigate the local flame front structures of turbulent premixed methane/air jet flames in order to reveal details about turbulence and flame interaction. The targeted turbulent flames were generated on a specially designed coaxial jet burner, in which low speed stoichiometric gas mixture was fed through the outer large tube

Performance Analysis and Energy Optimization of Wake-Up Receiver Schemes for Wireless Low-Power Applications

The use of duty-cycled ultralow-power wake-up receivers (WRxs) can significantly extend a node lifetime in low-power sensor network applications. In the WRx design, both the low-power operation of the WRx and the wake-up beacon (WB) detection performance are of importance. We present a system-level analysis of a duty-cycled WRx design, including an analog front end, a digital baseband, the WB stru

Crack Behavior near Reinforcing Bars in Concrete Structures

Currently used design methods predict that the crack widths at the concrete surface will increase significantly with concrete cover Requirements concerning limitation of crack widths therefore make it difficult to use large concrete covers, which are otherwise desirable to reduce the reinforcement corrosion. For this reason, it would be more relevant to use the crack width in the vicinity of the r

Ecological importance of the thermal emissivity of avian eggshells

Breeding birds have to divide their time between egg incubation and foraging. Particularly in cases when only one parent incubates the eggs, and especially in cold climates, the cooling of the eggs during absence from the nest may be problematic. In the present study we find that the thermal emissivity of eggshells may be ecologically important, and that an evolutionary pressure towards lower emis

Non-invasive imaging of microcirculation: a technology review.

Microcirculation plays a crucial role in physiological processes of tissue oxygenation and nutritional exchange. Measurement of microcirculation can be applied on many organs in various pathologies. In this paper we aim to review the technique of non-invasive methods for imaging of the microcirculation. Methods covered are: videomicroscopy techniques, laser Doppler perfusion imaging, and laser spe

Risk and vulnerability analysis in society’s proactive emergency management: Developing methods and improving practices

Risk and vulnerability analyses can play important roles in the society’s proactive emergency management. This thesis addresses two ways of improving the analysis of risk and vulnerability analysis in this context. First, by developing methods for risk and vulnerability analysis of technical infrastructure networks and emergency response systems. Secondly, by aiming to improve practises related to

Treatment of Critical Limb Ischaemia

Recommendations stated in the TASC II guidelines for the treatment of peripheral arterial disease (PAD) regard a heterogeneous group of patients ranging from claudicants to critical limb ischaemia (CLI) patients. However, specific considerations apply to CLI patients. An important problem regarding the majority of currently available literature that reports on revascularisation strategies for PAD

Medierande verktyg i körledarpraktik – en studie av arbetssätt och handling i körledning med barn och unga.

Title: Mediating tools in the practice of choir directors – a study of working approaches and actions in choral conducting with children and youth. Abstract: In Sweden, approximately 5 % of the population sing in a choir or a singing group which means that about 500 000 people plus a number of choral conductors regularly meet in choir related practices. The aim of the present study is to describ

On the existence of complex-valued harmonic morphisms

Popular Abstract in Swedish En harmonisk morfi är en avbildning som bevarar harmoniska funktioner. De studerades först av Jacobi år 1848, han studerade dem i syfte att hitta harmoniska avbildningar från rummet till planet. Man kan visa att harmoniska morfier är precis de avbildingar som bevarar Brownska rörelser. En Brownsk rörelse är en typ av slumpvandring där riktingen i varje steg är likaförThis thesis consists of 4 papers, their content is described below: Paper I. We present a new method for manufacturing complex-valued harmonic morphisms from a wide class of Riemannian Lie groups. This yields new solutions from an important family of homogeneous Hadamard manifolds. We also give a new method for constructing left-invariant foliations on a large class of Lie groups producing harmoni

ETS Gene Fusions in Prostate Cancer: From Discovery to Daily Clinical Practice

Context. In 2005, fusions between the androgen-regulated transmembrane protease serine 2 gene, TMPRSS2, and E twenty-six (ETS) transcription factors were discovered in prostate cancer. Objective: To review advances in our understanding of ETS gene fusions, focusing on challenges affecting translation to clinical application. Evidence acquisition: The PubMed database was searched for reports on ETS

Colombian Children With Overweight and Obesity Need Additional Motivational Support at School to Perform Health-Enhancing Physical Activity

Aims: The aim of this study is to investigate associations of screen-time and physical activity (PA) with self-efficacy for PA, intrinsic motivation to PA and health-related quality of life (HRQoL) in Colombian schoolchildren from socioeconomically disadvantaged neighborhoods, and to compare these variables among children with normal-weight (NW), overweight (OW) and obesity (OB). Methods: In 678 s

Integration Options for High Energy Efficiency and Improved Economics in a Wood-to-Ethanol Process

Background: There is currently a steady increase in the use of wood-based fuels for heat and power production in Sweden. A major proportion of these fuels could serve as feedstock for ethanol production. In this study various options for the utilization of the solid residue formed during ethanol production from spruce, such as the production of pellets, electricity and heat for district heating, w

Nuclear matter effects on J/psi production in asymmetric Cu plus Au collisions at root S-NN=200 GeV

We report on J/psi production from asymmetric Cu + Au heavy-ion collisions at root S-NN = 200 GeV at the Relativistic Heavy Ion Collider at both forward (Cu-going direction) and backward (Au-going direction) rapidities. The nuclear modification of J/psi yields in Cu + Au collisions in the Au-going direction is found to be comparable to that inAu + Au collisions when plotted as a function of the nu

Validation of the Scandinavian guidelines for initial management of minimal, mild and moderate traumatic brain injury in adults.

Acute management of traumatic brain injury (TBI), in particular mild TBI, focuses on the detection of the 5-7 % who may be harboring potentially life-threatening intracranial hemorrhage (IH) using CT scanning. Guidelines intending to reduce unnecessary head CT scans using available clinical variables to detect those at high IH risk have shown varying results. Recently, the Scandinavian Neurotrauma