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Variabilní geometrie sacích a výfukových portů Wankelova motoru / Variable geometry of intake and exhaust ports of Wankel engineKrejčí, Tomáš January 2010 (has links)
The purpose of this thesis is to design the key parameters of the high-powered Walkel engine and to design a chamber side on the base of computed parameters so that it enables variable change of the intake and exhaust port geometry. Consequently, to carry out a flow simulation in both ports in designed chamber side in order to find out its flow character and geometry change reaction.
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Návrh jednotné koncepce teleskopů manipulátorů přepravek pro zakladače typu Navette a SMC / Unified Design of Box Gripper Telescopes for Navette and SMC Storage MachinesSojka, Michal January 2016 (has links)
The aim of this diploma thesis is unified design of box gripper telescopes for Navette and SMC storage machines. The work contains technical report and drawings documentation. The first part of technical report is aim to research of similar constructions used in the world. Followed by own construction solution, including needed calculation. At the final part of work was created a tolerance analysis of new telescope. The drawings documentation contains assembly and subassembly drawings.
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Ventilový rozvod přeplňovaného motoru formule Student / Valve Train for Turbocharged Formula Student EngineBuchta, Martin January 2016 (has links)
This diploma thesis deals with valve train design of turbocharged engine used in Formula Student category race car. Based on thermodynamic model, a proper valve timing was chosen to achieve maximum power at high engine speed. A kinematic model was used to compute final cam profiles and CAD model was created.
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Temporal Processing In The Amygdalo-Prefronto-Dorsostriatal Network In Rats / Traitement de l'information temporelle dans le réseau amygdalo-préfronto-dorsostriatal chez le ratTallot, Lucille 18 December 2015 (has links)
Le temps est une dimension essentielle de la vie. Il est nécessaire, entre autres, pour réaliser des mouvements coordonnés, pour communiquer, mais aussi dans la prise de décisions. L’objectif principal de cette thèse était de caractériser le rôle d’un réseau amygdalo-préfronto-dorsostriatal dans la mémorisation et l’encodage du temps chez le rat. Dans un premier temps, nous avons décrit le comportement temporel du rat lors d’une tâche de suppression conditionnée (i.e. la suppression d’une réponse instrumentale d’appui sur levier par la présentation d’un son associé à un stimulus aversif), démontrant ainsi un contrôle temporel fin du comportement dans une situation Pavlovienne aversive. Dans un deuxième temps, nous avons analysé les potentiels de champs locaux (analyse fréquentielle des activités oscillatoires) de notre réseau d’intérêt au début d’un apprentissage associatif et après surentraînement dans la tâche de suppression conditionnée. En effet, le comportement temporel moteur nécessite un grand nombre de séances d’apprentissage pour devenir optimal, alors que l’apprentissage temporel est, lui, très rapide. Cette étude nous a permis de caractériser des corrélats neuronaux temporels au sein de ce réseau, que ce soit au niveau des structures individuelles ou au niveau de l’interaction entre ces structures. De plus, ces corrélats neuronaux sont modifiés selon le niveau d’entraînement des animaux. Enfin, dans une troisième étude, nous avons démontré que des ratons juvéniles (pré-sevrage), qui présentent un cortex préfrontal ainsi qu’un striatum dorsal immatures, peuvent mémoriser et différencier des intervalles de temps, ouvrant donc la question sur le rôle de ce réseau dans l’apprentissage temporel au cours du développement. / Time is an essential dimension of life. It is necessary for coordinating movement, for communication, but also for decision-making. The principal goal of this work was to characterize the role of an amygdalo-prefronto-dorsostriatal network in the memorization and encoding of time in a rat model. Firstly, we described temporal behavior in a conditioned suppression task (i.e. the suppression of an instrumental lever-pressing response for food by the presentation of a cue associated with an aversive event), therefore showing a precise temporal control in Pavlovian aversive conditioning. Secondly, we measured local field potentials in our network of interest at the beginning of associative learning and after overtraining in the conditioned suppression task. In effect, motor temporal behavior requires a large number of training sessions to become optimum, but temporal learning happens very early in training. This study allowed us to characterize, using frequency analysis of oscillatory activities, neuronal correlates of time in this network both at the level of individual structures, but also in their interactions. Interestingly, these neural correlates were modified by the level of training. Finally, we demonstrated that juvenile rats (pre-weaning), with an immature prefrontal cortex and dorsal striatum, can memorize and discriminate temporal intervals, raising questions on the role of this amygdalo-prefronto-dorsostriatal network in temporal learning during development.
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Follow-up and dynamical analysis of Kepler targets with transit timing variationsFreudenthal, Jantje 01 November 2019 (has links)
No description available.
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Instruction Timing Analysis for Linux/x86-based Embedded and Desktop SystemsJohn, Tobias 19 October 2005 (has links)
Real-time aspects are becoming more important in
standard desktop PC environments and x86 based
processors are being utilized in embedded systems
more often.
While these processors were not created for use
in hard real time systems, they are fast and
inexpensive and can be used if it is possible
to determine the worst case execution time.
Information on CPU caches (L1, L2) and
branch prediction architecture is necessary
to simulate best and worst cases in execution
timing, but is often not detailed
enough and sometimes not published at all.
This document describes how the underlying
hardware can be analysed to obtain
this information.
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Robustness Mechanisms of Temporal Cell-Fate Progression in C. ElegansIlbay, Orkan 16 December 2019 (has links)
Robustness is a ubiquitous property of biological systems, however, underlying mechanisms that help reinforce the optimal phenotypes despite environmental or physiological perturbations are poorly understood.
C. elegans development consists of four larval stages (L1-L4) and well-characterized invariant cell lineages, within which the heterochronic pathway controls the order and timing of cell-fates. Environmental or physiological stress signals can slow or temporarily halt larval stage progression; remarkably, however, temporal cell-fate progression remains unaffected.
We show that two widely conserved signaling pathways, insulin and TGF- β, that regulate C. elegans larval stage progression in response to starvation and crowding, respectively, also regulate a rewiring of the heterochronic pathway so that cell-fates remain temporally anchored to appropriate larval stages. This rewiring is mediated by the nuclear hormone receptor DAF-12, and it involves a shift from the reliance on let-7-family microRNAs to the reliance on LIN-46 for proper downregulation of the transcription factor, Hunchback-like-1 (HBL-1), which promotes L2 cell-fates and opposes L3 cell-fates. LIN-46 (which is a homolog of bacterial molybdopterin molybdenum transferase (moeA) and human gephyrin) post-translationally inhibits HBL-1 activity. LIN-46 expression is repressed by the RNA-binding protein LIN-28 at the early stages to permit HBL-1 activity and hence the proper execution of L2 cell-fates.
Our results indicate that robustness mechanisms of temporal cell-fate progression in C. elegans involves 1) coordinated regulation of temporal cell-fates and larval stage progression and 2) collaboration between translational regulation exerted by microRNAs and post-translational regulation exerted by LIN-46 to coordinate HBL-1 downregulation with stage progression.
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A distributed, mobile positioning systemfor wireless, handheld devicesChristiansson, Fredrik January 2000 (has links)
This thesis investigates the possibilities of implementing a location awareness mechanism for the so-called lesswire localNavigator. The author claims that it is possible to implement such a mechanism within the given prerequisites and constraints, even though with today’s technology it may not be economically feasible. Due to the lesswire’s constraints: high accuracy (67%), high-resolution (12 m2) and no hardware modification allowed to the mobile device, the suggested scheme uses Time Difference Of Arrival technology (TDOA). The main advantage of TDOA, as stated in this thesis, is the fact that it is almost totally independent of the preferred wireless technology of the mobile device. TDOA technology therefore, can be applied to a wide range of wireless networks (primarily TDMA, CDMA, FDMA – based). A disadvantage of this scheme is the fact that the network infrastructure needs to be extremely well synchronized - which in turn implies higher costs. Depending on how the synchronization problem is solved, the proposed system may well be economically feasible in the near future.
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Knowledge Transfer and The Timing of Information Technology Methods : A study within six organizations in Sweden during the COVID-19 pandemicLarsson, Filip, Thorsell, Anna January 2021 (has links)
Abstract Title: Information Technology and the Timing of Knowledge Transfer Methods: A study within six organizations in Sweden Level: Master Thesis for Master’s Degree in Business Administration Author: Anna Thorsell and Filip LarssonSupervisor: Daniella FjellströmExaminer: Ehsanul Huda Chowdhury Date: 2021 June Aim: It has been stated that knowledge transfer processes fail due to poorly timed transfer methods and that it is of importance to understand underlying mechanisms of transfer. It has also been argued that information technology (IT) systems can increase knowledge transfer in organizations. This study aims to research the influence IT has on the timing of transfer methods and knowledge transfer. The authors of this study discovered a gap for the use and timing of IT transfer methods and its influence on knowledge transfer within organizations in existing research. Method: This study included the use of secondary data from a literature review, as well as primary data using a qualitative research method with an inductive approach as semi- structured in-depth interviews were conducted for a multi-case study. The interviews were held with individuals working in six organizations in Sweden. Phases of analysis including content analysis and data coding were used for the analysis and reporting of the data collected. Findings and Conclusion: The study showed that IT provides platforms for knowledge transfer through different types of IT and IT transfer methods used. That the type of IT chosen can depend on the urgency of the transfer, what type of knowledge is transferred as well as the amount of knowledge transferred. That the timing of IT transfer methods I can speed up knowledge transfer as it enables the transfer to happen faster and in later stages of the transfer process due to providing direct knowledge transfer channels and accessible knowledge to all members of a team. It was shown that IT transfer methods can influence internal stickiness, decrease causal ambiguity and reduce the knowledge barrier of arduous relationships as well as influence the use of front-loading and back- loading modes of transfer. That the urgency of transfer can be a determining factor for the modes used rather than the level of causal ambiguity of the knowledge. Contribution of the Study: This study contributes to studies on types of IT and IT transfer methods used in organizations for knowledge transfer. It adds to existing research on timing of knowledge transfer methods including both explicit and tacit knowledge, as well as adding the influence of IT on the timing of knowledge transfer methods, knowledge transfer, internal stickiness, knowledge barriers and affordance of interaction. It provides new findings to the timing of knowledge transfer from the timing of types of IT and IT transfer methods used based on the urgency of transfer and what type of knowledge that is being transferred. The study contributes to highlighting the value of IT for the management of knowledge transfer within organizations, especially due to global events such as the COVID-19 pandemic. The study provides a basis for managers to examine their use of IT for knowledge transfer in organizations. It also showcases the continuous increased need for effective knowledge transfer processes between organizations, people and across locations and how IT can facilitate that. Study Reflections and Suggestions for Future Research: This study included individuals from six organizations. It is suggested to include more participants for future studies as well as investigating teams, departments and organizations on narrow as well as on broader levels in different sectors to gain deeper insight into the field. Further research on how the urgency of transfer affects the modes of transfer used is also advised. Keywords: Knowledge, Knowledge Transfer, Methods of Transfer, Timing, Modes of Transfer, Internal Stickiness, Information Technology, COVID-19
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Étude probabiliste des contraintes de bout en bout dans les systèmes temps réel / Probabilistic study of end-to-end constraints in real-time systemsMaxim, Cristian 11 December 2017 (has links)
L'interaction sociale, l'éducation et la santé ne sont que quelques exemples de domaines dans lesquels l'évolution rapide de la technologie a eu un grand impact sur la qualité de vie. Les entreprises s’appuient de plus en plus sur les systèmes embarqués pour augmenter leur productivité, leur efficacité et leurs valeurs. Dans les usines, la précision des robots tend à remplacer la polyvalence humaine. Bien que les appareils connectés comme les drônes, les montres intelligentes ou les maisons intelligentes soient de plus en plus populaires ces dernières années, ce type de technologie a été utilisé depuis longtemps dans les industries concernées par la sécurité des utilisateurs. L’industrie avionique utilise des ordinateurs pour ses produits depuis 1972 avec la production du premier avion A300; elle a atteint des progrès étonnants avec le développement du premier avion Concorde en 1976 en dépassant de nombreuses années les avions de son époque, et ça a été considéré comme un miracle de la technologie. Certaines innovations et connaissances acquises pour le Concorde sont toujours utilisées dans les modèles récents comme A380 ou A350. Un système embarqué est un système à microprocesseur qui est construit pour contrôler une fonction ou une gamme de fonctions et qui n’est pas conçu pour être programmé par l'utilisateur final de la même manière qu'un ordinateur personnel. Un système temps-réel est un système de traitement de l’information qui doit répondre aux stimuli d’entrées générées de manière externe dans une période finie et spécifiée. Le comportement de ces systèmes prend en compte non seulement l'exactitude dépend non seulement du résultat logique mais aussi du temps dans lequel il a été livré. Les systèmes temps-réel peuvent être trouvés dans des industries comme l'aéronautique, l'aérospatiale, l'automobile ou l’industrie ferroviaire mais aussi dans les réseaux de capteurs, les traitements d'image, les applications multimédias, les technologies médicales, les robotiques, les communications, les jeux informatiques ou les systèmes ménagers. Dans cette thèse, nous nous concentrons sur les systèmes temps-réel embarqués et pour la facilité des notations, nous leur nommons simplement des systèmes temps réel. Nous pourrions nous référer aux systèmes cyber-physiques si tel est le cas. Le pire temps d’exécution (WCET) d'une tâche représente le temps maximum possible pour qu’elle soit exécutée. Le WCET est obtenu après une analyse de temps et souvent il ne peut pas être déterminé avec précision en déterminant toutes les exécutions possibles. C'est pourquoi, dans l'industrie, les mesures sont faites uniquement sur un sous-ensemble de scénarios possibles, celui qui générerait les temps d'exécution les plus élevés, et une limite supérieure de temps d’exécution est estimé en ajoutant une marge de sécurité au plus grand temps observé. L’analyses de temps est un concept clé qui a été utilisé dans les systèmes temps-réel pour affecter une limite supérieure aux WCET des tâches ou des fragments de programme. Cette affectation peut être obtenue soit par analyse statique, soit par analyse des mesures. Les méthodes statiques et par mesure, dans leurs approches déterministes, ont tendance à être extrêmement pessimistes. Malheureusement, ce niveau de pessimisme et le sur-provisionnement conséquent ne peut pas être accepté par tous les systèmes temps-réels, et pour ces cas, d'autres approches devraient être prises en considération. / In our times, we are surrounded by technologies meant to improve our lives, to assure its security, or programmed to realize different functions and to respect a series of constraints. We consider them as embedded systems or often as parts of cyber-physical systems. An embedded system is a microprocessor-based system that is built to control a function or a range of functions and is not designed to be programmed by the end user in the same way that a PC is. The Worst Case Execution Time (WCET) of a task represents the maximum time it can take to be executed. The WCET is obtained after analysis and most of the time it cannot be accurately determined by exhausting all the possible executions. This is why, in industry, the measurements are done only on a subset of possible scenarios (the one that would generate the highest execution times) and an execution time bound is estimated by adding a safety margin to the greatest observed time. Amongst all branches of real-time systems, an important role is played by the Critical Real-Time Embedded Systems (CRTES) domain. CRTESs are widely being used in fields like automotive, avionics, railway, health-care, etc. The performance of CRTESs is analyzed not only from the point of view of their correctness, but also from the perspective of time. In the avionics industry such systems have to undergo a strict process of analysis in order to fulfill a series of certification criteria demanded by the certifications authorities, being the European Aviation Safety Agency (EASA) in Europe or the Federal Aviation Administration (FAA) in United States. The avionics industry in particular and the real-time domain in general are known for being conservative and adapting to new technologies only when it becomes inevitable. For the avionics industry this is motivated by the high cost that any change in the existing functional systems would bring. Any change in the software or hardware has to undergo another certification process which cost the manufacturer money, time and resources. Despite their conservative tendency, the airplane producers cannot stay inactive to the constant change in technology and ignore the performance benefices brought by COTS processors which nowadays are mainly multi-processors. As a curiosity, most of the microprocessors found in airplanes flying actually in the world, have a smaller computation power than a modern home PC. Their chips-sets are specifically designed for embedded applications characterized by low power consumption, predictability and many I/O peripherals. In the actual context, where critical real-time systems are invaded by multi-core platforms, the WCET analysis using deterministic approaches becomes difficult, if not impossible. The time constraints of real-time systems need to be verified in the context of certification. This verification, done during the entire development cycle, must take into account architectures more and more complex. These architectures increase the cost and complexity of actual, deterministic, tools to identify all possible time constrains and dependencies that can occur inside the system, risking to overlook extreme cases. An alternative to these problems is the probabilistic approach, which is more adapted to deal with these hazards and uncertainty and which allows a precise modeling of the system. 2. Contributions. The contribution of the thesis is three folded containing the conditions necessary for using the theory of extremes on executions time measurements, the methods developed using the theory of extremes for analyzing real-time systems and experimental results. 2.1. Conditions for use of EVT in the real-time domain. In this chapter we establish the environment in which our work is done. The use of EVT in any domain comes with a series of restrictions for the data being analyzed. In our case the data being analyzed consists in execution time measurements.
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