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HCCI (Homogeneous Charge Compression Ignition) is a very control-intensive combustion concept which has been studied for over a decade because of its favorable combination of high efficiency and low emissions. Various optimal control methods have been applied to HCCI and this chapter gives an overview of them. Optimal control of HCCI can be divided into model based and non-model based where MPC is

Partially premixed combustion is a compression ignited combustion strategy where high exhaust gas recirculation (EGR) levels in combination with early or late injection timing result in a prolonged ignition delay yielding a more premixed charge than with conventional diesel combustion. With this concept it is possible to get low smoke and NOx emissions simultaneously. Accurate control of injection

Previous research carried out by the authors described the role of dual-fuel combustion efficiency on overall engine efficiency at high diesel substitution ratio. At low loads, high diesel substitution ratios result in excessive total unburned hydrocarbon emissions due to bulk flame quenching, and consequently lower substitution ratios in combination with intake air heating, throttling and increas

The effects of fuel properties on the performance and emissions of an engine running in partially premixed combustion mode were investigated using nine test fuels developed in the gasoline boiling point range. The fuels covered a broad range of ignition quality and fuel chemistry.The fuels were characterized by performing a load sweep between 1 and 12 bar gross IMEP at 1000 and 1300 rpm. A heavy d

Background: A panel of four kallikrein markers (total, free, and intact prostate-specific antigen [PSA] and human kallikrein-related peptidase 2 [hK2]) improves predictive accuracy for Gleason score ≥7 (high-grade) prostate cancer among men biopsied for elevated PSA. A four-kallikrein panel model was originally developed and validated by the Dutch center of the European Randomized Study of Screeni

It has recently been found that anti-Stokes photoluminescence can be observed in degenerately n-doped indium phosphide nanowires, when exciting directly into the electron gas. This anti-Stokes mechanism has not been observed before and allows the study of carrier relaxation and recombination using standard photoluminescence techniques. It is important to know if this anti-Stokes photoluminescence

Avalanche photodetectors (APDs) are key components in optical communication systems due to their increased photocurrent gain and short response time as compared to conventional photodetectors. A detector design where the multiplication region is implemented in a large band gap material is desired to avoid detrimental Zener tunneling leakage currents, a concern otherwise in smaller band gap materia

This paper provides a descriptive analysis of the level of and change in cigarette smoking, excessive alcohol consumption and body weight in Nordic countries and compares them with non-Nordic OECD countries. Our results show that the average prevalence of daily smokers is significantly lower for Nordic countries compared to non-Nordic countries. Four out of five Nordic countries are below the non-

There is an increasing body of evidence that the intensity in which alcohol is drunk is of greater concern than the frequency or overall quantity consumed. This paper provides an extensive analysis of the demand for alcohol as measured by total quantity, frequency, and intensity. A unique large sample of cross-sectional data from Sweden 2004–2011 allows reduced-form alcohol demand equations to be

Background: The health care costs of kidney transplantation and dialysis are generally unknown. This study estimates the Swedish health care costs of kidney transplantation and dialysis over 10 years from a health care perspective.Method: A before–after design was used, in which the patients served as their own controls. Health care costs the year before transplantation were assumed to continue in

A novel approach to the synthesis of Mn-doped InSb nanowires is demonstrated in this work. We first report on the preparation of InSb nanowires without high temperature treatment. Indium nanowires are grown by glance angle deposition and then coated with a layer of Sb. Single crystalline InSb nanowires are obtained by annealing In/Sb nanostructures at 200 °C. Triple-layer In/Mn/Sb nanostructures a

Signatures of Majorana-fermion bound states in one-dimensional topological-insulator (TI) nanowires with proximity-effect-induced superconductivity are studied. The phase diagram and energy spectra are calculated for single-TI nanowires, and it is shown that the nanowires can be in the topologically invariant phases of winding numbers W=0,±1, and ±2, corresponding to the cases with zero, one, and

Nanowires hold great promise as tools for probing and interacting with various molecular and biological systems. Their unique geometrical properties (typically <100 nm in diameter and a few micrometers in length) enable minimally invasive interactions with living cells, so that electrical signals or forces can be monitored. All such experiments require in situ high-resolution imaging to provide co

Semiconductor nanowires show a great deal of promise for applications in a widerange of important fields, including photovoltaics, biomedicine, and informationtechnology. Developing these exciting applications is strongly dependent onunderstanding the fundamental properties of nanowires, such as their opticalresonances and absorption spectra. In this thesis we explore optical absorption spectra of

Gallium nitride based light-emitting diodes (LEDs) are presently fundamentally transforming the lighting industry, but limitations in the materials and fabrication methods of LEDs introduce substantial challenges to their future development. Among the remaining key bottlenecks of GaN LEDs are the resistive losses and current crowding that strongly increase the heat generation at high powers. In th