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Impact des conflits sur les forêts en Europe. Première application de l’anthracologie sur des camps militaires modernes, du XVIème au début du XIXème siècle.
No full textExploring superlongevity in the nematode Caenorhabditis elegans and the role of trehalose in its lifespan determination
Get PDFThe idea of global sociology in the international sociological agenda : unity and diversity of interpretations
No full textThis dissertation focuses on the idea of global sociology and the history of the debate on this issue. It is believed that sociology is a discipline, which exists in leading research centers in North America and Europe. Among the names of both sociological classics and contemporary authors, the overwhelming majority of researchers either come from these regions, or at least have a relation to them. Nevertheless, recently the voices of sociologists of the so-called global South have been heard more and more often, calling for their ideas to be accepted into the sociological family. Sociological practices are reproduced not only in the global North, but also in other countries around the world. It gave rise to a debate on the nature of sociological science, the implementation of its practices in local-national contexts.
Discussions on this issue arise at that time when sociologists of the global South claim their right to indigenous sociologies as well as to an alternative non-Western (Eurocentric) history of sociology. The monopoly of the global North on the production of sociological knowledge is considered as an unfair state of affairs. This situation is perceived by them as a sufficient basis for the decolonization of the discipline and for taking into account alternative southern theories. The latter notion is a label that we put on ideas that were born in opposition to the approaches of northern universalism in sociology. Such approaches cannot in any way get rid of the birth trauma – opposition to the North. They initially proceed from the opposite premise, which means that they oppose an already existing sociological order. The big question is whether such theories are capable of offering their own positive agenda without the presence of a northern ideological opponent.
The dissertation offers for consideration issues related to the formation of the sociological canon in the cradle of Western culture and its transformation. Special attention is paid to the global North and South, their emergence as well as the question of how this division affects sociology. In addition, the main ideas in the stated field from different parts of the world are considered, which are traditionally not taught in classical university courses and offer an alternative view of both the history of sociology and methods of sociological theorizing.
The first chapter is devoted to the context of the discussion, which is necessary for understanding what is happening in global sociology today. The second chapter deals with the universalism / particularism opposition and the substantive arguments of the authors. The third chapter is an analysis of the understanding of global sociology as a struggle "for a better world" and aspirations to establish the egalitarian coexistence of national / indigenous sociologies in the world.
It is necessary to present a brief history of the debate on this issue, together with a reconstruction of the intellectual history of the idea of global sociology. In addition, due to the fact that sociologists, while arguing on this issue, use different strategies for understanding the declared idea, there is a need to present a map of ideas, which means to systematize the debates associated with global sociology. These are the main tasks, which have been solved within the framework of the dissertation
Ascaridoid nematodes in fish : occurrence, diversity, and evaluation of candling towards exploring the public health relevance in Belgium
No full textAscaridoids are marine nematodes occurring in a wide range of fish hosts. In the intermediate fish host, L3 (third stage) larvae reside in the viscera (primary infection site) and can migrate, both post- and ante-mortem to the fish musculature. Humans are accidental dead-end host, and may develop gastro-intestinal complaints after ingestion of a viable larva, or acquire allergic symptoms even after ingestion of a dead larva or residual allergens. The industry is tasked with the detection and removal of these larvae, in absence of a fast, cheap, and highly sensitive detection technique. Remaining larvae may, besides representing a food safety problem, trigger consumers complaints. The objectives of this thesis were to estimate the occurrence of ascaridoids in fish destined for the Belgian market; and to assess the sensitivity of the current mostly used diagnostic tool in fish, namely candling
ETS1 and RUNX2 : two important transcriptional regulators of human NK cell development, phenotype and function
No full textA qualitative representation of moving point configurations with illustrations in micro traffic analysis
No full textMoving objects are an undeniable part of our everyday life. Tracking moving objects generates spatiotemporal data that describes the change in their position at a given place and time. Nowadays, this spatiotemporal data is widely available and can be digitally stored, indexed, processed and analysed. Often, this data is confusing and does not provide easily accessible information. Hence, more advanced methods for managing, accessing, and interpreting data are required as this data becomes richer and more complicated. For this reason, the representation and analysis of this data has received a lot of attention in the last two decades in various research areas such as human mobility research, intelligent transportation, urban planning and ecological studies. Existing studies have shown that one of the main goals of spatiotemporal data analysis is prediction, which can be achieved by discovering underlying patterns in movements. Various patterns, features, anomalies and useful knowledge can be extracted from massive data of moving objects. However, with advances in location-based technologies such as the Global Positioning System, the traditional
representation of motion data has changed. Now we have to deal with representing data in more than one direction and dimension. By dimensions, we mean data that have a vast amount of variables, e.g., traffic datasets generally have many attributes related to vehicles like their length, width, acceleration, etc. By direction, we mean the direction of flow of movement, since moving objects rarely move uniformly in one direction. Conventional methods for representing and
analysing data in only two dimensions or directions are therefore not sufficient to cope with the heterogeneity of the increasing movement data. To make the best use of this data, we need new qualitative techniques that not only represent spatiotemporal data, but also support data mining if needed. We focus on the qualitative description of movements, as people usually prefer to communicate in qualitative categories that support their intuition, rather than in quantitative categories. Nevertheless, the question remains unclear how to adequately qualitatively represent movement data, and in particular the interaction between moving objects, on a micro-scale.
With some of these challenges in mind, in this thesis, we introduce a new qualitative spatiotemporal approach to represent motion data as the Point-Descriptor-Precedence (PDP) representation. This approach qualitatively represents (moving) point configurations along straight and curved directed lines by a system of relational symbols () based on two distance descriptors: one representing the distance along the curved directed line and the other representing the signed orthogonal distance to the curved directed line, measured positive on the left and negative on the right with respect to direction. The directed line represents the direction of the movement flow . For example, it can be straight, as in the case of a motorway, or curved, as in the case of an intersection or roundabout. Following the Point Calculus, the order between points on the curved directed line is described by a small set of binary relations () acting on the distance descriptors. We refer to this representation as the Point-Descriptor-Precedence-Static (PDPS) representation at a point in time and the Point-Descriptor-Precedence-Dynamic (PDPD) representation during a time interval. A combination of PDPS and PDPD is also represented as Point-Descriptor-Precedence-General (PDPG). The PDPG representation can represent movements at time points and during time intervals simultaneously. After the introduction and a detailed overview of the existing spatiotemporal approaches in Chapter 1, the PDP representation and its different types are defined in Chapter 2. Furthermore, some basic examples from traffic micro-analysis are used to explain how this representation can be used to represent and analyse movements. A procedure for extracting movement patterns
from a motion dataset based on the PDPS representation is also described. Chapter 3 addresses some extensions of our approach to highlight the practical advantages of the PDP representation in identifying movement patterns that could be useful in geographic information systems, autonomous vehicles, sports analysis and gait analysis.
To illustrate how the PDP representation provides a good solution for studying the interaction of traffic flows at intersections, Chapter 4 presents a novel approach to retrieving and representing micro-level interactions between traffic movements using the case study of an non-signalised T-junction. Why intersections? Because an intersection of two or more roads poses a risk for potential conflicts between vehicles. Often the reasons that trigger such conflicts are not visible to the human eye. The environment also plays a role in understanding where, when and why a particular vehicle
interaction occurred in a particular way. Therefore, it is of utmost importance to further investigate vehicle interaction at the micro-scale within the embedded geographic environment, especially at intersections. This would in turn help to assess the relationship between vehicle interactions and conflict risks and near misses. Furthermore, the detection of such micro-traffic interactions could be used to improve the complexity of the already existing transport infrastructure. On the other hand, intersection traffic has been researched mainly in terms of traffic flow estimation, capacity and width measurements, traffic congestion, etc., while the detection of micro-traffic interactions at intersections is still relatively unexplored. In contrast to conventional approaches, we start our approach with actual movements before modelling the static intersection environment. Furthermore, we discuss with illustrative examples how length, width and speed of vehicles can be used in our approach to detect specific patterns more accurately.
An example of a significantly big data representation and analysis using the PDP representation is explored in Chapter 5. Here, we have obtained a real traffic flow of a multi-lane highway and created a sufficiently big traffic dataset for the busiest and the least busy hours on a weekday. The dataset is generated from the video of a weekday by extracting the -coordinates of the vehicles present during the selected traffic hours. The PDP representation is then used to identify and distinguish the different instances of the lane-changing manoeuvre in the dataset as potentially safe and unsafe. We have focused only on the micro-scale variations of the lane-changing manoeuvre, as this manoeuvre is quite common among vehicles and is considered one of the riskier driving manoeuvres. In the future, other types of manoeuvres could be studied to optimise things further. Moreover, vehicle automation is rapidly becoming a reality and it is crucial to identify the cases where such a manoeuvre can lead to an unsafe situation. To this end, we take into account not only
the dimensions of the vehicle, but also the micro-scale variations in the vehicle’s speed and its distance from other vehicles. Our approach automatically detects such micro variations in lane-changing manoeuvres registered in a multi-lane highway traffic dataset. With this approach, we have shown that it is possible to probe deeper into the micro-scale variations in traffic movements. This work is part of a broader study on “how movements can be adequately defined within a qualitative domain to provide a tool for both data and knowledge representation and spatiotemporal data retrieval”. A comprehensive study of the practical applications, implementation and technical aspects of the PDP representation is needed to provide a complete answer to this question. Despite the fact that automation will bring a number of new challenges, we are confident that this work can serve as a basis for implementation in an information system that can process quasi-continuous movement data
Growing up in the big data era : an investigation of the role of advertising literacy in children’s responses to commercial data collection and personalized advertising
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Thermal modelling of a steel slab in a continuous walking beam reheat furnace of a hot strip mill
No full textSteel reheating is one of the most energy-intensive steps in the process of steel manufacturing. A reheat furnace is used to heat steel to about 1200°C. This is achieved by the combustion of energy-dense fuels like coal or natural gas. The combustion of these fuels results in high amounts of CO2 emissions, thus any gains in the energy efficiency of the system have a major impact. In order to improve the process, a detailed investigation of the system is necessary. However, considering the high temperatures inside the furnace, it is impractical to conduct an elaborate experimental campaign. Computational fluid dynamics (CFD) is very useful in this regard. However, current CFD methods are either computationally very expensive or rely on too many simplifications. In this research, a novel modelling technique, called the Truncated Transient Slab Model, was developed to accurately and efficiently simulate the newly installed reheat furnace at ArcelorMittal Gent. Compared to the state-of-the-art, this new methodology is capable of simulating a furnace system thrice the size in half of the simulation time, using only a third of the computational resource