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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
141

The Happening of Tradition : Vallabha on Anumāna in Nyāyalīlāvatī

Sjödin, Anna-Pya January 2006 (has links)
The present dissertation is a translation and analysis of the chapter on anumāna in Vallabha’s Nyāyalīlāvatī, based on certain theoretical considerations on cross-cultural translation and the understanding of tradition. Adopting a non-essentialized and non-historicist conceptualization of the Nyāya-Vaiśeṣika/Navya-nyāya tradition, the work focuses on a reading of the anumāna chapter that is particularized and individualized. It further argues for a plurality of interpretative stances within the academic field of Nyāya-Vaiśeṣika/Navya-nyāya studies, on the grounds that the dominant stance has narrowed the scope of research. With reference to post-colonial theory, this dominant stance is understood in terms of a certain strategy called “mimetic translation”. The study of the anumāna chapter consists of three main interpretational sections: translation, comments, and analysis. The translation and comments focus on understanding issues internal to the Nyāyalīlāvatī. The analysis focuses on a contextual interpretation insofar as the text is understood through reading other texts within the Nyāya-Vaiśeṣika/Navya-nyāya discourse. The analysis is further grounded in a concept of intertextuality in that it identifies themes, examples, and arguments appearing in other texts within the discourse. The analysis also identifies and discusses Cārvāka and Mīmāṁsaka arguments within the anumāna chapter. Two important themes are discerned in the interpretation of the anumāna chapter: first, a differentiation between the apprehension of vyāpti and the warranting of this relation so as to make the apprehension suitable for a process of knowledge; second, that the sequential arrangement of the subject matter of the sections within the chapter, vyāptigraha, upādhi, tarka, and parāmarśa, reflects the process of coming to inferential knowledge. The present work is a contribution to the understanding of the post-Udayana and pre-Gaṅgeśa Nyāya-Vaiśeṣika/Navya-nyāya discourse on inferential knowledge and it is written in the hope of provoking more research on that particular period and discourse in the history of Indian philosophies.
142

Der hoch- und spätromanische Bauschmuck des Naumburger Domes im Zusammenhang der Baugeschichte / Architecture and decoration of the Romanesque Naumburg cathedral with regard to the history of its construction

Glaeseker, Michael 19 December 2001 (has links)
No description available.
143

Volume 2 – Conference

22 June 2020 (has links)
We are pleased to present the conference proceedings for the 12th edition of the International Fluid Power Conference (IFK). The IFK is one of the world’s most significant scientific conferences on fluid power control technology and systems. It offers a common platform for the presentation and discussion of trends and innovations to manufacturers, users and scientists. The Chair of Fluid-Mechatronic Systems at the TU Dresden is organizing and hosting the IFK for the sixth time. Supporting hosts are the Fluid Power Association of the German Engineering Federation (VDMA), Dresdner Verein zur Förderung der Fluidtechnik e. V. (DVF) and GWT-TUD GmbH. The organization and the conference location alternates every two years between the Chair of Fluid-Mechatronic Systems in Dresden and the Institute for Fluid Power Drives and Systems in Aachen. The symposium on the first day is dedicated to presentations focused on methodology and fundamental research. The two following conference days offer a wide variety of application and technology orientated papers about the latest state of the art in fluid power. It is this combination that makes the IFK a unique and excellent forum for the exchange of academic research and industrial application experience. A simultaneously ongoing exhibition offers the possibility to get product information and to have individual talks with manufacturers. The theme of the 12th IFK is “Fluid Power – Future Technology”, covering topics that enable the development of 5G-ready, cost-efficient and demand-driven structures, as well as individual decentralized drives. Another topic is the real-time data exchange that allows the application of numerous predictive maintenance strategies, which will significantly increase the availability of fluid power systems and their elements and ensure their improved lifetime performance. We create an atmosphere for casual exchange by offering a vast frame and cultural program. This includes a get-together, a conference banquet, laboratory festivities and some physical activities such as jogging in Dresden’s old town.:Group 1 | 2: Digital systems Group 3: Novel displacement machines Group 4: Industrial applications Group 5: Components Group 6: Predictive maintenance Group 7: Electro-hydraulic actuators / Der Download des Gesamtbandes wird erst nach der Konferenz ab 15. Oktober 2020 möglich sein.:Group 1 | 2: Digital systems Group 3: Novel displacement machines Group 4: Industrial applications Group 5: Components Group 6: Predictive maintenance Group 7: Electro-hydraulic actuators
144

Vybrané problémy vrcholně středověké transformace moravsko-slezského pomezí (ve světle archeologických pramenů) / Selected issues in the High Medieval transformation of the Moravian-Silesian border region (evidence from archeological sources)

Zezula, Michal January 2019 (has links)
Michal Zezula: Selected issues in the High Medieval transformation of the Moravian- Silesian border region (evidence from archeological sources) This study consists of three chapters and focuses on the Moravian-Silesian border region and its transformation during the High Middle Ages (in the 13th century). For most of the Early Middle Ages, this region lay on the boundary between the early Bohemian and Polish states, and after being annexed to the Přemyslid territories at the end of the 12th century it underwent fundamental changes, which are symbolized by the early emergence of institutionalized towns within the Bohemian Lands. The first chapter focuses on the Golensizi region in the Early Middle Ages, particularly on the village of Holasovice, which has attracted the attention of archeologists and historical researchers for over two centuries. Based on an assessment of older and more recent archeological discoveries and surveys, the significance of the location during the second half of the 12th century and the first half of the 13th century has been determined. Although there is at present no relevant archeological information which would provide evidence of the role played by Holasovice in the structures of the Piast state, its status as a local- level administrative centre in the Přemyslid-controlled...
145

Challenges for novel lead-free Alloys in Hydraulics

Reetz, Björn, Münch, Tileman 23 June 2020 (has links)
Different special brass (e.g. CuZn37Mn3Al2PbSi) and bronze alloys (e.g. CuPb15Sn) are well known for use in oil-hydraulics having in common to be alloyed with lead. The lead content of special brass alloys in this use ranges from 0.1 to 2.0 mass-%. Some bronze alloys provide even much higher contents of lead of 10 to 15 mass-%. Typically, lead is considered for improvement of machinability or castability. Beyond this purpose lead in brass and bronze alloys affects many more properties of manufacturing and application. During the shaping of the parts by means of hot or cold forming often the materials are strained close to their limits. Thanks to lead cracking is prevented during this process. Lead is also of great importance for the improvement of tribological systems. The surfaces of these systems are exposed to friction and wear. Lead is incorporated in the surface layers and supports the tribological system in their running-in process to achieve a steady state of friction and wear. Above all lead is unique because it forms no solid solution with copper or brass and forms no compounds with other typical copper alloying elements. The feasibility assessment of elements in order to substitute lead in brass or bronze alloys has to be done for each alloy and application individually. In oil-hydraulic applications as bushings, slippers or distributor plates, lead-free alloys must fulfil different profiles of requirements, depending on the conditions of manufacturing and application. The requirements do not only include mechanical strength, formability and thermal strength, but also fatigue strength, low friction and high wear resistance and lubricant compatibility. Consequently, the substitution of lead in brass and bronze alloys for application in oil-hydraulics is a challenging task. This does not only apply for the requirements for machining and forming, but particularly for the need of the new alloys to function under wear, friction and corrosion. Examples are given for how these challenges of new lead-free special brass alloys can be met in bushings (machining, friction properties), slippers (forming, strength) and distributor plates (fatigue strength) for axial piston pumps. Further on, new lead-free special brass alloys for contact with environmentally compatible lubricants are presented. All these examples show that there is not the one and only lead-free alloy for applications in oil-hydraulics. In fact, every application requires a different alloy which is composed and processed individually to meet the specific demands.
146

Researches on waterhydraulic motor

Majdič, Franc 23 June 2020 (has links)
Tribology has been recognized as a very important discipline in different branches of industry because almost every mechanical system has some moving parts. Due to the relative motion between these different mechanical parts, a variety of contacts are formed, and they are very often lubricated with oil. Environmental protection and ecological awareness are becoming increasingly important, which in turn has resulted in the shift to a low-carbon society, making water more interesting as a possible lubricant. On the one hand, water is less environmentally damaging as a lubricant than oil, but on the other hand, water has very poor lubrication properties, as its viscosity is 100 times lower than the viscosity of oil. These limitations might be overcome by appropriate surface engineering (e.g., diamond-like carbon, DLC). Tribological tests were performed in oil and water for two different contacts. Steel/steel and steel/DLC were investigated. DLC was recognized as a very promising solution, which ensures low friction and low wear. DLC was deposited on a real hydraulic part in an orbital hydraulic motor and tested under real industrial conditions. The overall efficiency of the hydraulic motor was measured.
147

Frequency based efficiency evaluation - from pattern recognition via backwards simulation to purposeful drive design

Starke, Martin, Beck, Benjamin, Ritz, Denis, Will, Frank, Weber, Jürgen 23 June 2020 (has links)
The efficiency of hydraulic drive systems in mobile machines is influenced by several factors, like the operators’ guidance, weather conditions, material respectively loading properties and primarily the working cycle. This leads to varying operation points, which have to be performed by the drive system. Regarding efficiency analysis, the usage of standardized working cycles gained through measurements or synthetically generated is state of the art. Thereby, only a small extract of the real usage profile is taken into account. This contribution deals with process pattern recognition (PPR) and frequency based efficiency evaluation to gain more precise information and conclusion for the drive design of mobile machines. By the example of an 18 t mobile excavator, the recognition system using Hidden – Markov - Models (HMM) and the efficiency evaluation process by means of backwards simulation of measured operation points will be described.
148

Optimization of operation strategy for primary torque based hydrostatics drivetrain using artificial intelligence

Xiang, Yusheng, Geimer, Marcus 23 June 2020 (has links)
A new primary torque control concept for hydrostatics mobile machines was introduced in 2018 [1]. The mentioned concept controls the pressure in a closed circuit by changing the angle of the hydraulic pump to achieve the desired pressure based on a feedback system. Thanks to this concept, a series of advantages are expected [2]. However, while working in a Y cycle, the primary torque controlled wheel loader has worse performance in efficiency compared to secondary controlled earthmover due to lack of recuperation ability. Alternatively, we use deep learning algorithms to improve machines’ regeneration performance. In this paper, we firstly make a potential analysis to show the benefit by utilizing the regeneration process, followed by proposing a series of CRDNNs, which combine CNN, RNN, and DNN, to precisely detect Y cycles. Compared to existing algorithms, the CRDNN with bidirectional LSTMs has the best accuracy, and the CRDNN with LSTMs has a comparable performance but much fewer training parameters. Based on our dataset including 119 truck loading cycles, our best neural network shows a 98.2 % test accuracy. Therefore, even with a simple regeneration process, our algorithm can improve the holistic efficiency of mobile machines up to 9% during Y cycle processes if primary torque concept is used.
149

A closed circuit electro-hydraulic actuator with energy recuperation capability

Qu, Shaoyang, Fassbender, David, Vacca, Andrea, Busquets, Enrique, Neumann, Uwe 23 June 2020 (has links)
The recent electrification trend in the off-road market has incentivized research towards the proposal of compact, cost-effective and energy-efficient solutions for hydraulic actuators. As a result, increased attention has been given to electro-hydraulic actuator (EHA) architectures. The paper offers a study performed on a novel closed-circuit EHA architecture with the goal to maximize the overall system efficiency while meeting or exceeding traditional off-road applications performance, thereby enabling further electrification of off-road applications. Both numerical and experimental approaches are utilized to validate the functionality of the proposed EHA circuital configuration in four quadrants. Moreover, the actuator functionality at both high and low velocities are considered, which has never been explored in the past due to the limitations on the hydraulic machine driving speed. The good match between the experimental data and the simulation results confirms the potential of the simulation model for sizing such EHA architecture for different actuator sizes, duty cycles, and performance levels.
150

Experimental evaluation of an electro-Hydrostatic actuator for subsea applications in a hyperbaric chamber

Duarte da Silva, João Pedro, Neto, Amadeu Plácido, De Negri, Victor Juliano, Orth, Alexandre 23 June 2020 (has links)
A novel Electro-Hydrostatic Actuator (EHA) prototype – designed to operate on subsea gate valves in deep and ultra-deep water – is analysed and qualified in terms of functionality under design and normative constraints. The prototype is assembled in a test bench for load control in a hyperbaric chamber where the high subsea environmental pressure can be emulated. The process variables under evaluation are monitored through a set of pressure and position sensors, which are part of the prototype design. The experimental results demonstrate a robust behaviour of the actuator concerning the imposed external pressure and load forces even with a forced limitation in its power input. Moreover, the prototype performs consistently throughout the entire endurance trial, asserting high reliability. With the results obtained, the subsea EHA concept is effectually eligible to a technology readiness level 4, according to the API 17N.

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