Filetype
Traditionally, diesel engine control has had to rely on indirect feedback variables and empirical open-loop maps because direct measurements of the variables representing high-level objectives, such as emissions, have not been available in production engines. With new sensors being developed, the opportunity opens to design the controller directly based on high-level objectives. In this paper, we
This study investigates mode switching from spark ignited operation with early intake valve closing to residual gas enhanced HCCI using negative valve overlap on a port-fuel injected light-duty diesel engine. A mode switch is demonstrated at 3.5 bar IMEPnet and 1500 rpm. Valve timings and fuel amount have to be selected carefully prior to the mode switch. During mode transition, IMEPnet deviates b
Positioning is an essential feature in Narrow-Band Internet-of-Things (NB-IoT) systems. Observed Time Difference of Arrival is one of the supported positioning techniques for NB-IoT. It utilizes the downlink NB positioning reference signal (NPRS) generated based on a length-31 Gold sequence. Although a Gold sequence has good auto-correlation and cross-correlation properties, the correlation proper
We consider time-of-arrival (ToA) estimation for a device working in narrowband Internet-of-Things (NB-IoT) systems. Due to a limited 180 kHz bandwidth, the time-domain auto-correlation function (ACF) of transmitted NB positioning reference signal (NPRS) has a wide main-lobe. Without considering that, the performance of ToA estimation can be degraded for two reasons. Firstly, the NPRS correspondin
We propose an improvement over a modulus zero-forcing (MZF) detector proposed earlier in [1] for multi-input multi-output (MIMO) detection, namely, the joint MZF (JMZF) detector. The MZF detector provides better detection-performance than a traditional ZF detector through preserving controllable interferences, which are mitigated later by nonlinear modulus arithmetic operation. However, the MZF de
In massive MIMO systems the uplink pilot signalstransmitted by a terminal define the channel seen by the basestation. This gives the terminal some degree of freedom selectingan uplink pilot transmission strategy. In this paper, we investigatethe benefit of different pilot transmission strategies when increasingthe number of antennas in the terminal. Building on previouswork on a simulation framewo
Over Boreal regions, monoterpenes emitted from the forest are the main precursors for secondary organic aerosol (SOA) formation and the primary driver of the growth of new aerosol particles to climatically important cloud condensation nuclei (CCN). Autoxidation of monoterpenes leads to rapid formation of Highly Oxygenated organic Molecules (HOM). We have developed the first model with near-explici
We investigate the importance of weak clusters when modeling a wireless massive MIMO channel. We do this by studying the influence of densely spaced terminals and the number of base-station antennas for a zero-forcing precoded massive MIMO system. In particular, we focus on the influence on the correlation and imbalance between the signals at the terminal antennas, the effective channel-gain, the
Many application areas for embedded systems, such as DSP, media coding, and image processing, are based on stream processing. Stream programs in these areas are often naturally described as graphs, where nodes are computational kernels that send data over the edges. This structure also exhibits large amounts of concurrency, because the kernels can execute independently as long as there are data to
Monte Carlo ray tracing offers the capability of rendering scenes with large numbers of area light sources---lights can be sampled stochastically and shadowing can be accounted for by tracing rays, rather than using shadow maps or other rasterization-based techniques that do not scale to many lights or work well with area lights. Current GPUs only afford the capability of tracing a few rays per pi
Fifth-generation (5G) new radio (NR) deployments are being rolled out in both the C–band (3.3 - 5.0 GHz) and millimeter-wave (mmWave) band (24.5 - 29.5 GHz). For outdoor scenarios, the C–band is expected to provide wide area coverage and throughput uniformity, whereas the mmWave band is expected to provide ultra-high throughput to dedicated areas within the C-band coverage. Due to the differences
We present recent results on spatially coupled turbolike codes and point out a connection to the self-concatenatedtrellis construction proposed by Loeliger in 1997 [1].
Network Function Virtualization (NFV) has shifted communication networks towards more adaptable software solutions, but this transition raises new security concerns, particularly in public cloud deployments. While Intel’s Software Guard Extensions (SGX) offers a potential remedy, it requires complex application adaptations. This paper investigates AMD’s Secure Encrypted Virtualization (SEV) as an
The introduction of standardized APIs for ray tracing, together with hardware acceleration, opens up possibilities for physically based lighting in real-time rendering. Light importance sampling is one of the fundamental operations in light transport simulations, applicable to both direct and indirect illumination. This chapter describes a bounding volume hierarchy data structure and associated sa
The purpose of this study was to increase the understanding of the phenomenon that there are so many young people placed in institutions in Sweden despite the valuable knowledge regarding the problems and risks of doing so. The questions that follow in the essay were what guided the social workers to choose institutional placement for youngsters. It went on to also ask if this knowledge could cont
Syftet med denna studie är att generera en kunskap kring hur fysiska butiker idag parerar den alltmer digitaliserade konsumenten samt hur de arbetar för att bibehålla sin position på marknaden. Studien har skett på butiksnivå och forskningsansatsen är kvalitativ där insamlingen av empiri skett i form av nio stycken djupintervjuer med både butikschefer och regionchefer från modeföretag som verkar p
The cosmogenic radionuclide 36Cl is a valuable tracer for studying Earth system processes, solar variability and geomagnetic field changes. These applications rely on a comprehensive understanding of 36Cl transport and deposition processes, which are still poorly studied. In this study, we apply a state-of-the-art climate model ECHAM6.3-HAM2.3 to investigate the source distribution and deposition
We study mixed-integer optimal control problem using indirect approaches. The proposed method relies on splitting algorithms which separate the mixed problem into two solvable pieces and then iteratively alternating between the two. The algorithm gives approximated local solutions, and provides lower and upper bounds estimations of the global optimum. Simulations are provided to validate our appro
In this paper, we present a system for drone detection and positioning. The approach uses a system composed of an audio detection rig with a set of microphones, a set of fixed cameras with a large combined field of view and a Pan-TiltZoom camera. We present how this system can be defined in an efficient and modular way with a number of parallel sensing modules. The focus of this work is the audio
Side-channel attacks exploiting Plaintext-Checking (PC) and Decryption Failure (DF) oracles are a pressing threat to deployed post-quantum cryptography. These oracles can be instantiated from tangible leakage sources like timing, power, and microarchitectural behaviors, making them a practical concern for leading schemes based on lattices, codes, and isogenies. In this paper, we revisit chosen-cip
