Sökresultat

Modern transportation requires advanced powertrain systems to reduce the production of greenhouse gas CO2. Partially premixed combustion (PPC) is one of the most promising methods to achieve low emission and low fuel consumption of internal combustion engines. The present paper evaluated the effects of the calibration parameters on the efficiency and emissions of a multi-cylinder engine using PPC

Future applications of internet of things (IoT) will go far beyond connecting sensors to the internet. The real challenge lies in how to easily build well working systems of things: well integrated distributed applications that support users, yet built from a variety of devices running on a variety of networks and protocols, and including services that were not designed to interoperate.Based on ou

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].

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

In this study, we investigate integrating eye tracking with auditory attention decoding (AAD) using portable EEG devices, specifically a mobile EEG cap and cEEGrid, in a preliminary analysis with a single participant. A novel audiovisual dataset was collected using a mobile EEG system designed to simulate real-life listening environments. Our study has two main objectives: (1) to use eye tracking

ASG Innovation for whom Universities as drivers of social innovation for inclusive development In the ongoing refugee crisis in Europe, 162 877 persons applied for asylum in Sweden in 2015. Integrating hundreds of thousands of new arrivals into the Swedish society in the coming years is but one example of societal challenges that will require social innovations, not least within Higher Educational

https://www.pi.lu.se/en/sites/pi.lu.se.en/files/pa_innovation_for_whom.pdf - 2026-05-30

In this short note, we argue that performance per watt, which is often cited in the graphics hardware industry, is not a particularly useful unit for power efficiency in scientific and engineering discussions. We argue that joules per task and watts are more reasonable units. We show a concrete example where nanojoules per pixel is much more intuitive, easier to compute aggregate statistics from,

Application of the faster than Nyquist signaling method to the upcoming fifth generation wireless system