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The Global ETD Search service is a free service for researchers
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Showing 561 to 569 of 569 (0.026 seconds)Spelling suggestions: "subject:"logik"" "subject:"gogik""
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Energy-aware localization based on an optimized anchor deployment in wireless sensor networksEl Houssaini, Dhouha 16 January 2023 (has links)
Various applications of Wireless Sensor Networks (WSNs) require accurate localization of sensor nodes. The quantity and locations of anchor nodes, which serve as reference points for distance estimates, as well as the localization process itself, affect the localization accuracy. Furthermore, because numerous communications are sent between nodes for localization, energy consumption must be considered. This work presents an energy-aware and accurate localization method. It is based on a combined anchor deployment and energy-aware localization. The proper number and distribution of anchors have been investigated to achieve full network coverage and connectivity based on an efficient and heterogeneous hexagonal deployment. Later, energy-aware localization is performed in three stages: Initialization, signal acquisition, and anchor selection. The initialization step allows the network to be adaptable to sudden changes by establishing anchor connectivity and creating the neighbors' list. Meanwhile, the Received Signal Strength Indicator (RSSI) is used for distance measurements between nodes, with the implementation of a Kalman
filter to reduce signal attenuation and noise. Later, the anchor selection is done using fuzzy logic with inference parameters: RSSI, node density, and residual energy. This step ensures that only operable anchors engage in localization, while anchors with inadequate energy sources remain intact to ensure their future availability.:1 Introduction
2 Theoretical background
3 Energy-aware outdoor deployment and localization
4 Proposed anchor deployment method
5 Proposed energy-aware localization method
6 Experimental validation of the proposed localization method / Verschiedene Anwendungen von drahtlosen Sensornetzwerken (WSNs) erfordern eine genaue Lokalisierung von Sensorknoten. Die Anzahl und Standorte der Ankerknoten, die als Referenzpunkte für Entfernungsschätzungen dienen, sowie der Lokalisierungsprozess selbst beeinflussen die Lokalisierungsgenauigkeit. Da für die Lokalisierung zahlreiche Nachrichten zwischen den Knoten gesendet werden, muss außerdem der Energieverbrauch berücksichtigt werden. In dieser Arbeit wird eine energiebewusste und genaue Lokalisierungsmethode vorgestellt. Sie basiert auf einer Kombination aus effizienter Ankerknotennutzung und energiebewusster
Lokalisierung. Die richtige Anzahl und Verteilung von Ankern wurde untersucht, um eine vollständige Netzabdeckung und Konnektivität auf der Grundlage einer effizienten und heterogenen hexagonalen Verteilung zu erreichen. Später wird die energiebewusste Lokalisierung in drei Stufen durchgeführt: Initialisierung, Signalerfassung und Ankerauswahl. Der Initialisierungsschritt ermöglicht es dem Netzwerk, sich an plötzliche Veränderungen anzupassen, indem es die Verbindung zu den Ankern und die Liste der Nachbarn erstellt. Zunächst wird der Received Signal Strength Indicator (RSSI) für die Entfernungsmessung zwischen den Knoten verwendet, wobei ein Kalman-Filter implementiert wird, um Signalabschwächung und Rauschen zu reduzieren. Später erfolgt die Ankerauswahl mit Hilfe von Fuzzy-Logik und Inferenzparametern: RSSI, Knotendichte und Restenergie. Dieser Schritt stellt sicher, dass nur funktionsfähige Anker an der Lokalisierung teilnehmen, während Anker mit unzureichenden Energiequellen intakt bleiben, um ihre zukünftige Verfügbarkeit zu gewährleisten.:1 Introduction
2 Theoretical background
3 Energy-aware outdoor deployment and localization
4 Proposed anchor deployment method
5 Proposed energy-aware localization method
6 Experimental validation of the proposed localization method
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Mer än bara fotboll : En etnografisk studie av fotbollens samhällsnytta: när idrott förväntas agera och lösa sociala utmaningar i en segregerad storstad / More than just football : An ethnographic study of the societal benefits of football: when sport is expected to act and solve social challenges in a segregated cityÖström, Niklas January 2022 (has links)
This master’s thesis in ethnology aim to enlighten the driving forces behind why a local football club, in a segregated residential area, outside of Stockholm in Sweden, chooses to develop its association in a more social direction. This is a cultural study of why football, as a cultural phenomenon, is expected to be able to solve social problems, and more generally how is sport considered a tool and a solution to social problems? Why is football expected to be able to solve segregation in a socio-economically vulnerable areas, of those who lead the sports activities? The empirical material of this essay has been collected through oral interviews from leaders of the association and government officials. Material from the association's development documents, state active board members from the association, government documents, and news articles have also been analyzed. By using the Political Discourse Theory by Ernesto Laclau and Chantal Mouffe (2008 [1985]), the situations for how the sports activities have been designed can be seen as made in relation to the general hegemonic discourse on the social benefits of sport. It is also possible to discover how government grants work as guidelines and point out what the sports movement should perform under state supervision. Logics of Critical Explanation in Social and Political Theory (2007), by Jason Glynos and David Howarth, are used in the analysis and especially their fantasmatic logic has given this study an insight into the idea or perception that football leaders have of the outside world, in this case the idea of the social benefit of sport. Which in turn can explain why they in turn invest their commitment in and attract their drive from these ideas because the conviction is about being able to change the socio-economic situation in their local area. In the end, however, it turns out that neither sport nor football alone cannot serve as the solution in the fight against child poverty, criminal activity, and segregation. Sport’s simply does not have all the characteristics required to reform, challenge, or question a social order created or even built on inequality and segregation. But this in no way takes sport into account in contexts where it can socially contribute to a community that can play a significant role for its participants in their everyday lives.
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| 563 |
A Fuzzy Controller Design for a Mechatronic Ski BindingHermann, Aljoscha, Baumeister, Dirk, Carqueville, Patrick, Senner, Veit 14 October 2022 (has links)
Mechatronic Ski Bindings are the most promising technical solution to reduce knee injuries in alpine skiing. The key to a successful system is the algorithm controlling the bindings adaption of the retention values. A fuzzy controller has advantages compared to classical controllers due to missing information about injury mechanisms and the complex dynamics of the skier. We present a controller structure and test it using the injury case reported in the literature. / Mechatronische Skibindungen sind die vielversprechendste technische Lösung zur Reduzierung von Knieverletzungen im alpinen Skisport. Der Schlüssel zu einem erfolgreichen System ist der Algorithmus, der die Anpassung der Bindungen an die Haltewerte steuert. Ein Fuzzy-Regler hat Vorteile gegenüber klassischen Reglern, da Informationen über Verletzungsmechanismen und die komplexe Dynamik des Skifahrers fehlen. Wir stellen eine Reglerstruktur vor und testen sie anhand eines in der Literatur beschriebenen Verletzungsfalls.
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Mathematical Pluralism: Constructive Mathematics and Economic TheorySteins, Stefan Arno 09 December 2021 (has links)
Wir schlagen eine praxisorientierte Explikation der philosophischen Position des Mathematischen Pluralismus vor. Dieser Position zufolge existieren mehr als ein legitimes mathematisches System. Wir interpretieren 'legitim' als 'geeignet zur Realisierung wissenschaftlicher Ziele' und wenden die resultierende pluralistische Position auf die Mathematische Ökonomie an. Wir präsentieren ein begriffliches Rahmenwerk, in dem pluralistische Thesen formuliert und evaluiert werden können, stellen ein informelles System der Konstruktiven Mathematik als Alternative zur Klassischen Mathematik vor, und zeigen, dass verschiedene ökonomische Theoreme nicht konstruktiv beweisbar sind. Auf dieser Basis argumentieren wir, dass Pluralismus relativ zu Zielen mit Bezug zu Erklärung und Simplizität in der Ökonomie vorliegt. / We propose a practice-oriented explication of the philosophical position known as mathematical pluralism. According to this position there is more than one legitimate mathematical system. We interpret 'legitimate' as 'suitable for realizing scientific goals' and apply the resultant pluralist position to mathematical economics. We present a conceptual framework within which pluralist theses can be formulated and evaluated, introduce an informal system of constructive mathematics as an alternative to classical mathematics, and point out that central theorems of economic equilibrium theory are not constructively provable. On this basis, we argue that pluralism obtains with respect to goals related to explanation and simplicity in economics.
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IN - eine verteilte Service-Plattform mobiler Prozeßarchitekturen für verkehrstelematische Anwendungen / IN - adistributed service platform of mobile process architectures for traffic telematic applications / traffic telematics IN (eng)Riegelmayer, Wolfgang P. 14 February 2006 (has links) (PDF)
Der Paradigmenwechsel zur Entwicklungsmethodik innerhalb verteilter Kommunikationssysteme schlägt sich auch in der Telematik zum Anwendungspotential und Systemkomplexität nieder. Dies liefert eine neue Auffasung dessen, was den transparenten Datenkanal ausmacht.
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IN - eine verteilte Service-Plattform mobiler Prozeßarchitekturen für verkehrstelematische AnwendungenRiegelmayer, Wolfgang P. 09 January 2006 (has links)
Der Paradigmenwechsel zur Entwicklungsmethodik innerhalb verteilter Kommunikationssysteme schlägt sich auch in der Telematik zum Anwendungspotential und Systemkomplexität nieder. Dies liefert eine neue Auffasung dessen, was den transparenten Datenkanal ausmacht.
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| 567 |
In-Vitro Biological Tissue State Monitoring based on Impedance SpectroscopyGuermazi, Mahdi 04 May 2017 (has links)
The relationship between post-mortem state and changes of biological tissue impedance has been investigated to serve as a basis for developing an in-vitro measurement method for monitoring the freshness of meat. The main challenges thereby are the reproducible measurement of the impedance of biological tissues and the classification method of their type and state.
In order to realize reproducible tissue bio-impedance measurements, a suitable sensor taking into account the anisotropy of the biological tissue has been developed. It consists of cylindrical penetrating multi electrodes realizing good contacts between electrodes and the tissue. Experimental measurements have been carried out with different tissues and for a long period of time in order to monitor the state degradation with time. Measured results have been evaluated by means of the modified Fricke-Cole-Cole model. Results are reproducible and correspond to the expected behavior due to aging. An appropriate method for feature extraction and classification has been proposed using model parameters as features as input for classification using neural networks and fuzzy logic.
A Multilayer Perceptron neural network (MLP) has been proposed for muscle type computing and the age computing and respectively freshness state of the meat. The designed neural network is able to generalize and to correctly classify new testing data with a high performance index of recognition.
It reaches successful results of test equal to 100% for 972 created inputs for each muscle. An investigation of the influence of noise on the classification algorithm shows, that the MLP neural network has the ability to correctly classify the noisy testing inputs especially when the parameter noise is less than 0.6%. The success of classification is 100% for the muscles Longissimus Dorsi (LD) of beef, Semi-Membraneous (SM) of beef and Longissimus Dorsi (LD) of veal and 92.3% for the muscle Rectus Abdominis (RA) of veal.
Fuzzy logic provides a successful alternative for easy classification. Using the Gaussian membership functions for the muscle type detection and trapezoidal member function for the classifiers related to the freshness detection, fuzzy logic realized an easy method of classification and generalizes correctly the inputs to the corresponding classes with a high level of recognition equal to 100% for meat type detection and with high accuracy for freshness computing equal to 84.62% for the muscle LD beef, 92.31 % for the muscle RA beef, 100 % for the muscle SM veal and 61.54% for the muscle LD veal. / Auf der Basis von Impedanzspektroskopie wurde ein neuartiges in-vitro-Messverfahren zur Überwachung der Frische von biologischem Gewebe entwickelt. Die wichtigsten Herausforderungen stellen dabei die Reproduzierbarkeit der Impedanzmessung und die Klassifizierung der Gewebeart sowie dessen Zustands dar. Für die Reproduzierbarkeit von Impedanzmessungen an biologischen Geweben, wurde ein zylindrischer Multielektrodensensor realisiert, der die 2D-Anisotropie des Gewebes berücksichtigt und einen guten Kontakt zum Gewebe realisiert. Experimentelle Untersuchungen wurden an verschiedenen Geweben über einen längeren Zeitraum durchgeführt und mittels eines modifizierten Fricke-Cole-Cole-Modells analysiert. Die Ergebnisse sind reproduzierbar und entsprechen dem physikalisch-basierten erwarteten Verhalten. Als Merkmale für die Klassifikation wurden die Modellparameter genutzt.
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Complexity of Normal Forms on Structures of Bounded DegreeHeimberg, Lucas 04 June 2018 (has links)
Normalformen drücken semantische Eigenschaften einer Logik durch syntaktische Restriktionen aus. Sie ermöglichen es Algorithmen, Grenzen der Ausdrucksstärke einer Logik auszunutzen. Ein Beispiel ist die Lokalität der Logik erster Stufe (FO), die impliziert, dass Graph-Eigenschaften wie Erreichbarkeit oder Zusammenhang nicht FO-definierbar sind. Gaifman-Normalformen drücken die Bedeutung einer FO-Formel als Boolesche Kombination lokaler Eigenschaften aus. Sie haben eine wichtige Rolle in Model-Checking Algorithmen für Klassen dünn besetzter Graphen, deren Laufzeit durch die Größe der auszuwertenden Formel parametrisiert ist. Es ist jedoch bekannt, dass Gaifman-Normalformen im Allgemeinen nur mit nicht-elementarem Aufwand konstruiert werden können. Dies führt zu einer enormen Parameterabhängigkeit der genannten Algorithmen. Ähnliche nicht-elementare untere Schranken sind auch für Feferman-Vaught-Zerlegungen und für die Erhaltungssätze von Lyndon, Łoś und Tarski bekannt.
Diese Arbeit untersucht die Komplexität der genannten Normalformen auf Klassen von Strukturen beschränkten Grades, für welche die nicht-elementaren unteren Schranken nicht gelten. Für diese Einschränkung werden Algorithmen mit elementarer Laufzeit für die Konstruktion von Gaifman-Normalformen, Feferman-Vaught-Zerlegungen, und für die Erhaltungssätze von Lyndon, Łoś und Tarski entwickelt, die in den ersten beiden Fällen worst-case optimal sind.
Wichtig hierfür sind Hanf-Normalformen. Es wird gezeigt, dass eine Erweiterung von FO durch unäre Zählquantoren genau dann Hanf-Normalformen erlaubt, wenn alle Zählquantoren ultimativ periodisch sind, und wie Hanf-Normalformen in diesen Fällen in elementarer und worst-case optimaler Zeit konstruiert werden können.
Dies führt zu Model-Checking Algorithmen für solche Erweiterungen von FO sowie zu Verallgemeinerungen der Algorithmen für Feferman-Vaught-Zerlegungen und die Erhaltungssätze von Lyndon, Łoś und Tarski. / Normal forms express semantic properties of logics by means of syntactical restrictions. They allow algorithms to benefit from restrictions of the expressive power of a logic. An example is the locality of first-order logic (FO), which implies that properties like reachability or connectivity cannot be defined in FO. Gaifman's local normal form expresses the satisfaction conditions of an FO-formula by a Boolean combination of local statements. Gaifman normal form serves as a first step in fixed-parameter model-checking algorithms, parameterised by the size of the formula, on sparse graph classes. However, it is known that in general, there are non-elementary lower bounds for the costs involved in transforming a formula into Gaifman normal form. This leads to an enormous parameter-dependency of the aforementioned algorithms. Similar non-elementary lower bounds also hold for Feferman-Vaught decompositions and for the preservation theorems by Lyndon, Łoś, and Tarski.
This thesis investigates the complexity of these normal forms when restricting attention to classes of structures of bounded degree, for which the non-elementary lower bounds are known to fail. Under this restriction, the thesis provides
algorithms with elementary and even worst-case optimal running time for the construction of Gaifman normal form and Feferman-Vaught decompositions. For the preservation theorems, algorithmic versions with elementary running time and non-matching lower bounds are provided.
Crucial for these results is the notion of Hanf normal form. It is shown that an extension of FO by unary counting quantifiers allows Hanf normal forms if, and only if, all quantifiers are ultimately periodic, and furthermore, how Hanf normal form can be computed in elementary and worst-case optimal time in these cases. This leads to model-checking algorithms for such extensions of FO and also allows generalisations of the constructions for Feferman-Vaught decompositions and preservation theorems.
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Licence to Talk : Sustainability Managers and their Managerial Realities within the Corporate Sustainability ParadoxEl hajjari Borg, Mounia, Sundberg, Elin January 2021 (has links)
While sustainability-dedicated managers and related titles represent a profession that has hardly existed for more than a decade, it is not surprising that the field of research concentrating on these professionals is in itself relatively new. With an increasing demand for corporations to take their social and environmental responsibility, and a corporate sustainability characterized by tension and paradox, we found it of importance to explore the role and entanglements of these professionals. By analysing 17 in-depth interviews with sustainability-dedicated professionals from the private sector in Sweden, our interpretation is that sustainability managers hold the function of selling sustainability, with talk as their main weapon. Expressly, in the intersection between business-case logics and sustainability logics, sustainability managers have to, above all, make a convincing case for sustainability, inwards and outwards. Therefore, they draw dynamically on different narratives which we conceptualise in three roles: the chameleon, the pragmatic, and the nagging manager. Through these roles, we intend to capture the fluidity with which the managers relate and engage with sustainability, and hence we do not mean to ossify a role’s dynamics within a single, static or stereotypical category. We discuss these findings and concepts to the background of previous studies and existing literature.
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