Modeling engine spray ignition with igniting flamelets

Poster onl

Body Part-Based Representation Learning for Occluded Person Re-Identification

Occluded person re-identification (ReID) is a person retrieval task which aims at matching occluded person images with holistic ones. For addressing occluded ReID, part-based methods have been shown beneficial as they offer fine-grained information and are well suited to represent partially visible human bodies. However, training a part-based model is a challenging task for two reasons. Firstly, individual body part appearance is not as discriminative as global appearance (two distinct IDs might have the same local appearance), this means standard ReID training objectives using identity labels are not adapted to local feature learning. Secondly, ReID datasets are not provided with human topographical annotations. In this work, we propose BPBreID, a body part-based ReID model for solving the above issues. We first design two modules for predicting body part attention maps and producing body part-based features of the ReID target. We then propose GiLt, a novel training scheme for learning part-based representations that is robust to occlusions and non-discriminative local appearance. Extensive experiments on popular holistic and occluded datasets show the effectiveness of our proposed method, which outperforms state-of-the-art methods by 0.7% mAP and 5.6% rank-1 accuracy on the challenging Occluded-Duke dataset. Our code is available at https://github.com/VlSomers/bpbreid

Surgical antibiotic prophylaxis in a Belgian teaching hospital : a retrospective evaluation

C

Ignition and combustion characteristics of hydrotreated pyrolysis oil in a combustion research unit

Biomass-derived fuels are promising in reducing life-cycle CO2 emissions and achieving the goal of sustainable mobility in the future. This work investigates the ignition behavior and combustion process of hydrotreated pyrolysis oil (HPO) derived from various biomass resources. They are tested in a combustion research unit based on constant volume combustion technology, which imitates the ignition behavior in compression ignition engines. Various conditions are tested and HPO are benchmarked with commericially avalable biofuels and fossile fuels: hydrotreated vegetable oil (HVO) and fatty acid methyl ester (FAME), diesel, and marine gas oil. The results showed that the igntiion delay time follows an order of folloing: HPO &gt; diesel-like fuels &gt; HVO. Both the biomass type and after-treatment have a small influence on the ignition delay of HPO. Two combustion regimes are observed at different chamber temperature range. It also revealed that blending HPO into HVO can extend the ignition delay of HVO. And ignition delay of HVO/HPO increases as the HPO blend ratio increases. At 75 vol% HPO blend ratio, the HPO/HVO blend shows identical ignition and combustion behavior as diesel. In addition, the viscosity of HPO/HVO blends and diesel are also quite similar. The results indicated the possibility of using 100% bio-fuel in a modern marine engine to provide power to future mobility.</p

Progress in FGM-LES modeling of igniting n-heptane sprays in a constant volume

Abstract in article

Experimental study on the impact of operating conditions on PCCI combustion

In a short–term scenario, using near–standard components and conventional fuels, PCCI combustion relies on a smart choice of operating conditions. Here, the effects of operating conditions on ignition delay, available mixing time, combustion phasing and emissions are investigated. In the PCCI regime, NOX and smoke have been shown to be efficiently reduced with elongated mixing time. For viable PCCI combustion, one would require a Combustion Delay (CD) which is long enough to bring both NOX and smoke levels down to acceptable values. For the completeness of combustion, the resulting unburned hydrocarbon and carbon monoxide emissions, as well as the associated fuel consumption; mixing time should, however, be as short as possible. Most parameters strongly correlate with combustion delay, independent of how this is achieved. Lastly, the best points experienced for a number of cases are given

The transcriptional repressor complex FRS7-FRS12 regulates flowering time and growth in Arabidopsis

Most living organisms developed systems to efficiently time environmental changes. The plant-clock acts in coordination with external signals to generate output responses determining seasonal growth and flowering time. Here, we show that two Arabidopsis thaliana transcription factors, FAR1 RELATED SEQUENCE 7 (FRS7) and FRS12, act as negative regulators of these processes. These proteins accumulate particularly in short-day conditions and interact to form a complex. Loss-of-function of FRS7 and FRS12 results in early flowering plants with overly elongated hypocotyls mainly in short days. We demonstrate by molecular analysis that FRS7 and FRS12 affect these developmental processes in part by binding to the promoters and repressing the expression of GIGANTEA and PHYTOCHROME INTERACTING FACTOR 4 as well as several of their downstream signalling targets. Our data reveal a molecular machinery that controls the photoperiodic regulation of flowering and growth and offer insight into how plants adapt to seasonal changes