29 research outputs found
Interview with Derek Nikitas, part 1 of 2 [video]
No full textDerek Nikitas is a faculty member in the Creative Writing MFA Program and author of two recent mystery novels, The Long Division (2009) and Pyres (2007). Nikitas\u27 first novel was nominated for the prestigious Edgar award, and has been optioned for film adaptation by Vox3 Films. His second novel, The Long Division, is receiving rave reviews
Interview with Derek Nikitas, part 2 of 2 [video]
No full textDerek Nikitas is a faculty member in the Creative Writing MFA Program and author of two recent mystery novels, The Long Division (2009) and Pyres (2007). Nikitas\u27 first novel was nominated for the prestigious Edgar award, and has been optioned for film adaptation by Vox3 Films. His second novel, The Long Division, is receiving rave reviews
Κατανομή πόρων σε ενσωματωμένα επίγεια και μη επίγεια δίκτυα με παράλληλη ανάπτυξη αλυσίδας λειτουργιών υπηρεσίας υπό δυναμικές μεταβολές
No full textΕθνικό Μετσόβιο Πολυτεχνείο--Μεταπτυχιακή Εργασία. Διεπιστημονικό-Διατμηματικό Πρόγραμμα Μεταπτυχιακών Σπουδών (Δ.Π.Μ.Σ.) "Επιστήμη Δεδομένων και Μηχανική Μάθηση
Comparative Evaluation of Machine Learning Inference Machines on Edge-class Devices
No full textComputer science and engineering have evolved rapidly over the last decade offering innovative Machine Learning frameworks and high-performance hardware devices. Executing data analytics at the edge promises to transform the mobile computing paradigm by bringing intelligence next to the end user. However, it remains an open question to explore if, and to what extent, today's Edge-class devices can support ML frameworks and which is the best configuration for efficient task execution. This paper provides a comparative evaluation of Machine Learning inference machines on Edge-class compute engines. The testbed consists of two hardware compute engines (i.e., CPU-based Raspberry Pi 4 and Google Edge TPU accelerator) and two inference machines (i.e., TensorFlow-Lite and Arm NN). Through an extensive set of experiments in our bespoke testbed, we compared three setups using TensorFlow-Lite ML framework, in terms of accuracy, execution time, and energy efficiency. Based on the results, an optimized configuration of the workload parameters can increase accuracy by 10%, and in addition, the class of the Edge compute engine in combination with the inference machine affects execution time by 86% and power consumption by almost 145%.Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Embedded System
Conflits entre conventions collectives de niveaux différents : Étude comparative
No full textIn most countries labour collective bargaining takes place not only at one but at several levels. Thus is created the possibility — and the reality ! — of conflits between collective agreements at different levels, conflits which are multiplied through the growing diversification of the bargaining levels. The economic crisis has sometimes causes « cracks » to some acquisitions of the collective agreement's law, and so has accentuated the problems of these conflicts.
In this study the author tries to systematize this complex matter and to clarify some concepts on the basis of comparative observation and the general theory of law. So he proposes a more or less exhaustive typology of conflicts between collective agreements at different levels and of the principles of their solution. The basic distinction is that of conflicts of competence and conflicts of regulation(s). The conflicts of regulation(s) can be resolved by means of five rules of conflict of which the one, the principle of greatest advantage, has value of general principle provided his individualistic character is mitigated.Dans la plupart des pays les négociations collectives de travail ne se déroulent pas à un seul mais à plusieurs niveaux. De là la possibilité — et la réalité — de conflits entre conventions collectives de niveaux différents, conflits qui se multiplient avec la diversification croissante des niveaux de négociation. La crise économique ayant parfois provoqué des « fissures » à certains acquis du droit collectif conventionnel a accentué les problèmes de ces conflits.
Dans cette étude l'auteur essaie de systématiser cette matière complexe et de clarifier certains concepts sur la base de l'observation comparative et de la théorie générale du droit. Il propose ainsi une typologie, plus ou moins exhaustive, des conflits entre conventions collectives de niveaux différents et des principes de leur solution. La distinction de base est celle entre conflits de compétence et conflits de réglementation(s). Les conflits de réglementation(s) sont résolus à l'aide de cinq règles de conflit dont l'une, le principe de faveur, a valeur de principe général à condition que soit atténué son caractère individualiste.Aliprantis Nikitas. Conflits entre conventions collectives de niveaux différents : Étude comparative. In: Revue internationale de droit comparé. Vol. 39 N°1, Janvier-mars 1987. pp. 7-41
DC-DC Bidirectional Converter with USB Type-C for Power Delivery
No full textFocusing on real life commercial applications, this thesis presents the theoretical and practical control requirements of an application board, which exploits flexible bidirectional DC-DC converters, to power up a unit of multi USB type-C ports. Emphasis is given in the power management between the connected devices since the power flow is bidirectional.The USB type-C interface allows power management between the devices and offers the possibility of using the Li-ion batteries of the end-devices as a backup power source in case of a blackout or source failure. At the beginning of this research, the appropriate topology of the converter is defined based on the requirements of the application. The power stage and the system control is fully simulated to prove the application concept. The final stage is the design and implementation of the real application board to extract useful results regarding the viability and feasibility of producing such an integrated solution.The results arising from the application board prove the real application use. This research topic is setting the foundations for a further research on future applications of the USB type-C interface, in commercial or domestic buildings which are powered by a DC network.Electrical Engineering | Sustainable Energy Technolog
Athens by night : representations of gendered sexualities in Greek film noir of the 1950s and the 1960s
No full textThis dissertation examines Greek film noirs of the 1950s and the 1960s, focusing on gender and sexual representations. The author argues that discourses that run through both the filmic texts as well as other types of texts and media that constitute the films’ contexts coarticulate specific modern Greek gender and sexual identities
Dynamics of Intra-EMS Interest Rate Linkages
No full textinterest rates, long memory, error correction
Semantic 3D city models as support for urban flood resilience: Experiences from Rotterdam
No full textThis paper presents a process to develop a CityGML-based 3D city model that, together with results from a flood simulation, can be used to investigate direct and indirect effects of floods on a city, its inhabitants and its critical infrastructure, and to quantify such effects by means of a Flood Resilience Score. In addition, the model can be used as a spatial planning support tool for urban planners to prioritise the redevelopment of certain areas and to test new spatial design decisions. First, a semantic 3D city model is prepared and enriched with additional building and infrastructure information. Then a Flood Resilience Score (FReSco) is defined and computed by quantifying the direct and indirect impacts of flooding on buildings, households, and critical infrastructure points using information from both the 3D city model and the flood simulation results. Lastly, a prototype of a spatial planning support tool is proposed to evaluate the flood resilience of a new environmental plan. As a case study, the neighbourhood of “Nieuw Kralingen” in Rotterdam was chosen. Overall, the outcomes of this work are meant to help cities better understand the impacts of flooding and adjust their urban planning activities accordingly. At the same time, the developed methodology also tests the strengths and limits of CityGML-based 3D city models in combination with openly available data and software.Urban Data Scienc
Improving processor power demand comprehension in data-driven power and software phase classification and prediction
No full textThe single-core performance trend predicted by Moore's law has been impeded in recent years partly due to the limitations imposed by increasing processor power demands. One way to mitigate this limitation in performance improvement is the introduction of multi-core and multi-processor computation.
Another approach to increasing the performance-per-Watt metric is to utilize the processor's power more efficiently. In a single-core system, the processor cannot sustainably dissipate more than the nominal Thermal Design Power (TDP) limit determined for the processor at design time. Therefore it is important to understand and manage the power demands of the processes being executed. This principle also applies to multi-core and multi-processor environments. In a multi-processor environment, knowing the power demands of the workload, the power management unit can schedule the workload to a processor based on the state of each processor and process in the most efficient way. This is an example of the knapsack problem. Another approach, also applicable to multi-cores, could be to reduce the core's power by reducing its working voltage and frequency, leading to mitigation of the power bursts, lending more headroom to other cores, and keeping the total power under the TDP limit. The information collected from the execution of the software running on the processor (i.e. the workload) is the key to determining the actions needed with regards to power management at any given time.
This work comprises two different approaches in improving the comprehension of software power demands as it executes on the processor. In the first part of this work, the effects of software data on power is analysed. It is important to be able to model the power based on the instructions it comprises, however, to the best of our knowledge, no work exists in which the effects of the values being processed has been investigated with regards to processor power. Creating a power model capable of accurately reflecting the power demands of the software at any given time is a problem addressed by previous research. The software power model can be used in processor simulation environments as well as in the processor itself to create an estimated power dissipation without the need to physically measure the power. In the first part of this research, the effects of software data on power is investigated. In order to collect the data required as part of this research, a profiler tool has been developed by the author and used in this part of the research as well as the second part.
The second part of this work focuses on the development of processor power throughout time during the execution of the software. Understanding the power demands of the processor at any given time is important to maintain and manage processor power. Additionally, acquiring an insight into the future power demands of the software can help the system with scheduling planning ahead of time, in order to prepare for any high-power section of the code as well as to plan to use the available power headroom as a result of an upcoming low-power section. In this part of our work, a new hierarchical approach to software phase classification is developed. Software phase classification problem focuses on determining the behaviour of the software at any given time slice by assigning the time slice to one of pre-determined software phases. Each phase is assumed to have known behaviour which was previously measured and instrumented based on previously observed instances of the phase, or by utilizing a model capable of estimating the behaviour of each phase. Using a two-tiered hierarchical clustering approach, our proposed phase classification methodology incorporates the recent performance behaviour of the software in order to determine the power phase. We focused on determining the power phase using the performance information because the real processor power is not usually available without the need for added hardware, while there exists a large number of different performance counters available on most modern processors. Additionally, based on our observations, the relation between performance phases and power behaviour is highly predictable. This method is shown to provide robust results with a low amount of noise compared to other methods, while providing a high enough timing accuracy for the processor to act on. To the best of our knowledge, no other existing work is able to provide both timing accuracy and reduced noise compared to our work.
Software phase classification can be used to control the processor power based on the software's phase at any given time, but it does not provide future insight into the progression of the workload. Finally, we developed and compared several phase prediction methodologies based on phase precursors and phase locality concepts. Phase precursor-based methods rely on detecting the precursors observed before the software enters a certain phase, while phase locality methods rely on the locality principle, which postulates a high probability for the current software behaviour to be observed in the near-future. The phase classification, as well as phase prediction methodologies was shown to be able to reduce the power bursts within a workload in order to provide a more smooth power trace. As the bursts are removed from one workload's power trace, the multi-core processor power headroom can be confidently utilized for another process.Graduat
