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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.
691

Sukúky jako islámské investiční nástroje z pohledu české a evropské právní úpravy / Sukuk as Islamic Financial Instruments from the Perspective of Czech and European Law

Vojtěch, Jakub January 2019 (has links)
Sukuk are a special kind of securities based on Islamic law. Being an up-to-date and increasingly important instrument, sukuk are traded in financial markets of not only Muslim countries. The aim of the dissertation is to review this Islamic legal institute in its entirety and to examine it from the point of view of the Czech and European Union legal regulation of securities and financial instruments. The starting point of the dissertation is the assumption that by studying foreign law and comparing its institutes, it is possible to achieve a better understanding of one's own legal regulation and possibly create new solutions that would otherwise be hidden in the standard context of understanding national law. The dissertation deals with sukuk both in terms of their theoretical definition provided by the Islamic legal theory (the idealistic approach) as well as from the point of view of their actual form in practice as products of Islamic securitization (the pragmatic approach). The analysis of the examined legal institute results in a new definition of the concepts of sukuk and Islamic securitization. The paper further concentrates on the structures of a total of seven main types of sukuk, namely: (i) Sukuk al-Ijarah, (ii) Sukuk al-Murabahah, (iii) Sukuk as- Salam, (iv) Sukuk al-Istisna'a, (v)...
692

Cobrança sobre usos da água como instrumento econômico de gestão: o caso do reservatório de Salto Grande (Americana, SP) / Water charges as management economic instrument: case of Salto Grande reservoir (Americana, SP)

Pessoa, Carlos Alberto Perdigão 30 October 2002 (has links)
O presente trabalho contribui para a discussão e aplicação dos Instrumentos Econômicos (IEs) na gestão dos recursos hídricos, em especial a cobrança sobre usos da água, consideradas suas distintas possibilidades de implementação e metodologias aplicáveis. Foram analisadas algumas experiências internacionais e brasileiras no trato com os IEs e identificados os objetivos da utilização desses instrumentos nos respectivos sistemas de gestão. Essa análise revelou que, em determinados casos, a atuação dos IEs é descaracterizada pois não é atendido o objetivo precípuo desses instrumentos, qual seja, o incentivo ao uso adequado dos recursos hídricos. Para ilustrar a aplicação da cobrança sobre usos da água como instrumento econômico de gestão é utilizada a metodologia de SOUZA (1995). Foram realizadas simulações no reservatório de Salto Grande (Americana, SP) para os seguintes anos: 2000, 2005 e 2010. Os resultados indicam que a sazonalidade e os investimentos previstos para o controle de descargas poluentes influenciam, de maneira significativa, os valores cobrados nos cenários simulados. / The present work contributes to the discussion and application of economic instruments (EIs) for water management, especially water charging, considering their different implementation possibilities and applicable methodologies. Some international and Brazilian experiences about EIs were analyzed and identified the objectives of the use of these instruments at their respective water management systems. This analysis shows that, in some cases, the EIs loose its real features because the main objective of the instruments - the incentive of sustainable water use - is not satisfied. The work shows an application of water charges as management economic instrument, based on SOUZA (1995). Simulations were made in Salto Grande reservoir (Americana, SP) for the years 2000, 2005 and 2010. The results indicate that sazonability and foreseen investments for the pollutant discharge control are of great influence the charged value on the simulated scenarios.
693

Physical modelling of the bowed string and applications to sound synthesis

Desvages, Charlotte Genevieve Micheline January 2018 (has links)
This work outlines the design and implementation of an algorithm to simulate two-polarisation bowed string motion, for the purpose of realistic sound synthesis. The algorithm is based on a physical model of a linear string, coupled with a bow, stopping fi ngers, and a rigid, distributed fingerboard. In one polarisation, the normal interaction forces are based on a nonlinear impact model. In the other polarisation, the tangential forces between the string and the bow, fingers, and fingerboard are based on a force-velocity friction curve model, also nonlinear. The linear string model includes accurate time-domain reproduction of frequency-dependent decay times. The equations of motion for the full system are discretised with an energy-balanced finite difference scheme, and integrated in the discrete time domain. Control parameters are dynamically updated, allowing for the simulation of a wide range of bowed string gestures. The playability range of the proposed algorithm is explored, and example synthesised gestures are demonstrated.
694

Travelling wave control of stringed musical instruments

Donovan, Liam January 2018 (has links)
Despite the increasing sophistication of digital musical instruments, many performers, composer and listeners remain captivated by traditional acoustic instruments. Interest has grown in the past 2 decades in augmenting acoustic instruments with sensor and actuator technology and integrated digital signal processing, expanding the instrument's capabilities while retaining its essential acoustic character. In this thesis we present a technique, travelling wave control, which allows active control of the vibrations of musical strings and yet has been little explored in the musical instrument literature to date. The thesis seeks to demonstrate that travelling wave control is capable of active damping and of modifying the timbre of a musical string in ways that go beyond those available through the more conventional modal control paradigm. However, we show that travelling wave control is highly sensitive to nonlinearity, which in practical settings can lead to harmonic distortion and even instability in the string response. To avoid these problems, we design and build a highly linear optical string displacement sensor, and investigate the use of piezoelectric stacks to actuate the termination point of a string. With these components we design and build a functioning travelling wave control system which is capable of damping the vibrations of a plucked string without adversely affecting its timbre. We go on to show that by deliberately adding nonlinearity into the control system, we are able to modify the timbre of the string in a natural way by affecting the evolution of the modal amplitudes. The results demonstrate the feasibility of the concept and lay the groundwork for future integration of travelling wave control into future actuated musical instruments.
695

Ion probe measurement of oxygen self-diffusion in Al2O3.

Reed, David John January 1977 (has links)
Thesis. 1977. Sc.D.--Massachusetts Institute of Technology. Dept. of Materials Science and Engineering. / MICROFICHE COPY AVAILABLE IN ARCHIES AND SCIENCE. / Vita. / Includes bibliographical references. / Sc.D.
696

Novel Microfabrication Techniques Towards Next-Generation In Vitro and In Vivo Medical Devices

Chin, Sau Yin January 2015 (has links)
Microfabrication has given rise to numerous technologies and has resulted in new paradigms for how science and technology has advanced in recent years. Having originated from the microelectronics industry, microfabrication techniques have increasingly been leveraged in the development of various other fields. Such techniques have an increasing presence in the field of medical devices, especially with the advent of microfluidics. The capability that microfluidics lends to miniaturizing and making portable analytical tools was, and still is, extremely useful in the advancement of medical technologies. In this dissertation, we explore novel microfabrication techniques towards the development of next-generation medical devices. We can broadly classify these devices as devices that function in in vitro and in vivo settings. In vitro devices typically function in a non-invasive manner such as when patient samples are processed externally for diagnostic purposes. In vivo medical devices, on the other hand, normally play a role in disease treatment upon implantation into a patient, such as with stents, pacemakers and drug delivery devices. Here we demonstrate how microfabrication techniques can be implemented in the improvement of devices involved in diagnosis and treatment; two important branches of medical sciences that go hand in hand. Firstly, microfabrication and microfluidic techniques were implemented in developing a CD4+ T helper cell counter. This integrated device, where capture and analysis are performed on the same platform, also employs a chemiluminescence-based method of detection. This a rather simple and elegant technique that is amenable for miniaturization in future as it does not require the use of external complex light source (such as for fluorescence imaging) nor the use of image/data analysis methods. The second part of this dissertation describes novel microfabrication techniques for the development of a new class of implantable devices- hydrogel MEMS devices. This technique is comparable to additive manufacturing techniques such as 3D printing. Current 3D printing or fabrication techniques for biocompatible materials normally result in standalone structures. Using our technique, we are not only able to construct microcomponents entirely out of hydrogels but also have the capability to assemble and align various moving components to form a robust MEMS-like device. As these MEMS devices are constructed entirely out of biocompatible PEG-based hydrogels, they are ideal candidates for implantable devices. Once implanted, they can be wirelessly actuated using simple permanent magnets and the operation of the devices do not require onboard power-sources or electronics, which is common for current MEMS-based implantable devices. These devices can also be designed to deliver payloads and this delivery can be actively controlled. We also explore the use of hydrogel MEMS in the in vivo delivery of therapeutics, and assess its efficacy in delivering local, low-doses of a chemotherapeutic drug in a disease model. We envision that these devices, and the technology from which they are borne, will open up a new paradigm in the way implantable devices are developed.
697

Construction, Deployment and Data Analysis of the E and B EXperiment: A Cosmic Microwave Background Polarimeter

Didier-Scapel, Joy Maria Elise January 2016 (has links)
The E and B EXperiment (EBEX) is a pointed balloon-borne telescope designed to measure the polarization of the cosmic microwave background (CMB) as well as that from Galactic dust. The instrument is equipped with a 1.5 meter aperture Gregorian-Dragone telescope, providing an 8' beam at three frequency bands centered on 150, 250 and 410 GHz. The telescope is designed to measure or place an upper limit on inflationary B-mode signals and to probe B-modes originating from gravitationnal lensing of the CMB. The higher EBEX frequencies are designed to enable the measurement and removal of polarized Galactic dust foregrounds which currently limit the measurement of inflationary B-modes. Polarimetry is achieved by rotating an achromatic half-wave plate (HWP) on a superconducting magnetic bearing. In January 2013, EBEX completed 11 days of observations in a flight over Antarctica covering 6,000 square degrees of the southern sky. This marks the first time that kilo-pixel TES bolometer arrays have made science observations on a balloon-borne platform. In this thesis we report on the construction, deployment and data analysis of EBEX. We review the development of the pointing sensors and software used for real-time attitude determination and control, including pre-flight testing and calibration. We then report on the 2013 long duration flight (LD2013) and review all the major stages of the analysis pipeline used to transform the ~1 TB of raw data into polarized sky maps. We review "LEAP", the software framework developed to support the analysis pipeline. We discuss in detail the novel program developed to reconstruct the attitude post-flight and estimate the effect of attitude errors on measured B-mode signals. We describe the bolometer time-stream cleaning procedure including removing the HWP-synchronous signal, and we detail the map making procedure. Finally we present a novel method to measure and subtract instrumental polarization, after which we show Galaxy and CMB maps.
698

Análise dos critérios de outorga de direito de usos consuntivos dos recursos hídricos baseados em vazões mínimas e em vazões de permanência. / Analysis of grant criteria based on minimum flow and flow according to duration curve for water consumptive uses.

Mendes, Ludmilson Abritta 16 May 2007 (has links)
A Política Nacional de Recursos Hídricos acaba de completar dez anos, período ao longo do qual novos desafios se apresentaram ao gerenciamento dos recursos hídricos à medida que se consolidou a aplicação dos instrumentos de gestão, dentre eles a outorga de direito de uso. Os critérios comumente aplicados na determinação da disponibilidade hídrica para outorga, ao fixarem vazões muito restritivas como quantidade máxima outorgável, se mostraram inadequados à realidade de algumas bacias, que, em pouco tempo, se apresentaram com disponibilidade hídrica crítica ou em vias de criticidade, tendo a somatória das demandas consuntivas alcançado a restrita parcela destinada à outorga estabelecida em legislação. Neste trabalho buscou-se apresentar as inconveniências relacionadas ao uso da vazão mínima de 7 dias com 10 anos de recorrência - Q7,10 - e das vazões de permanência como referência para outorga. Através das leituras de vazões diárias de dois postos fluviométricos da bacia hidrográfica do rio Turvo, em São Paulo, já considerada crítica quanto à disponibilidade hídrica, foi calculada a Q7,10 por ajustes obtidos por quatro distribuições probabilísticas, e também foi construída a curva de permanência de vazões de ambos os postos. Os resultados foram usados no cálculo da vazão outorgável segundo os critérios estaduais baseados em vazão mínima e em vazão de permanência. Discutem-se, então, as imprecisões associadas à Q7,10 e às vazões de permanência em vários aspectos, bem como as inconveniências de se fixar um teto exíguo e universal de outorga a perfis de demandas distintos. Sugere-se, por fim, o abandono destes critérios de outorga e, a partir de algumas experiências de gestão de bacias críticas, apontam-se caminhos alternativos mais adequados, em especial a outorga negociada. / Through these ten years of the Water Resources Brazilian Policy, some difficulties have been presented to the water resources management in so far as the management instruments has becoming solid, mainly to the grant of right for using water resources. A problem of those refers to the low water availability in several water basins, where the total water demands exceed the maximum volume permitted in agreement with the law. This situation occurs by the state criteria which impose low limits for the surface outflows, expressed by minimum flow or flow according to duration curve. This work analyses the constraints when the hydrologic water availability is referred to the Q7,10 (minimum flow with duration of 7 days duration and 10 years of return period), to Q95% (flow equalized or overstated in 95% of the time) or to Q90%. These flows were calculated from the daily records in two hydrological stations located at Turvo River, State of São Paulo, where the consumptive uses are higher than the water availability. The Q7,10 flow was obtained through four probabilistic methods. Also the duration curves were obtained and the results was used to determine the maximum value granted according to state criteria referred to Q7,10, Q95% and Q90% flows. Then, it\'s argued the imprecision related to these three flows in several aspects and the inconvenience of fixing an scanty and universal ceiling to different demands profiles. In conclusion, it\'s suggested the substitution of these criteria and, through some cases of management of critical basins, it\'s pointed alternative methods of grant of right for using water resources.
699

Computational design and prototype development of optical prism for augmented reality projection.

January 2012 (has links)
虛擬現實(VR)為用家提供了一個結合了人工場境和現實世界的練習環境。隨著在醫療,軍事和娛樂行業日益增長的需求,虛擬現實化的設備將會越來越受歡迎。頭戴式顯示器(HMD)是一種利用自由曲面的光學棱鏡,以投射由微型顯示器顯示的圖像,讓用家能夠在近距離觀看和體驗虛擬環境的產品。 / 頭戴式顯示器由兩個基本部分組成,液晶顯示屏和一個光學元件,以能夠在很短的距離顯示圖像到用家的眼睛。光學自由曲面棱鏡在HMD研究中是一個主要的課題。設計的棱鏡需要運用大多數的光學理論和一些商業光學設計軟件的輔助。在市場,只有有限的光學軟件能深入地協助設計光學元件和系統。同時,成本高昂和不容易使用的光學軟件令到光學設計並不普及的原因。在下面的部分將用光學軟件ZEMAX去驗證每個設計。 / 自由曲面棱鏡的幾何形狀設計是為構建一個頭盔顯示器的關鍵問題。通常情況下,頭盔內自由曲面棱鏡由三面特別設計的非球面表面而組成。源圖像經過三個非球面反映後,可參照圖6,將圖像投射到人類視網膜上而形成圖像。棱鏡上的三個面的互相協調將是一個具有挑戰性的問題。 / 跟據現有的產品和研究分析,研發了一種新風格的棱鏡。在這篇論文中,由射線追踪和光學理論的幫忙,建議了一款凸-平棱鏡作HMD上的光學棱鏡。利用光學設計軟件分析和優化以追求一個可穿戴和低像差的光學棱鏡作目標。光學棱鏡中有兩個面為平面,因此光線能在棱鏡中穩步地轉化,從而,降低光學系統的像差。製作了經優化表面定位的原型,雖然原型是成本低,但它們比半透明的鏡子有一個更好的分辨率。在新設計的一個HMD上,一個廣闊和清晰的圖像將顯示。 / Virtual reality (VR) provides an artificial environment to user for practicing under a synthetic environment which merges the real world with artificial scene. In response to the growing demand in medical, military and entertaining application, devices that can simulate VR will become more and more popular. Head mounted display (HMD) is a kind of wearable products that utilize freeform optical prisms to project images generated by microdisplays, enabling users to situate in virtual environments. / HMD has two basic components, a LCD and an optical element, to display image to naked eye in a short distance. An optical freeform prism will be a main research topic in HMD. To design the prism will require substantial knowledge in optical theory and the aid of some commercial optical design software. In the market, there is limited number of software for in depth optical analysis. Meanwhile, costly and not user-friendly software is a problem of unpopularity of optical design. Zemax has been used for verifying the each design in the below sections. / The design of geometric shape for the freeform prism is crucial for constructing a HMD. Typically, the freeform prisms inside HMD comprise of 3 specially designed aspherical surfaces. The source image is reflected by those three surfaces to form image on human retina. The interplay of three surfaces will is the main challenging problem. With the analysis of existing products and researches, a new-style prism is proposed. In this thesis, with the aid of ray tracing and optical theory, a convex-plano prism is developed. / Analyses of optical design software and optimization are utilized to pursue the goal of wearable and low aberration HMD optical prism. Prototypes with the optimized surfaces alignment are fabricated. With two flat surfaces on the prism, the rays translate steadily in the prism. Hence, the optical system’s aberration is reduced. Although the prototypes are low cost, they have a better resolution than half-transparent mirror. Also a wide and clear image will show on the new style see-through HMD. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Ho, Pui Lam. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 57-59). / Abstracts also in Chinese. / Abstract --- p.i / Abstract (Chinese) 摘要 --- p.iii / Acknowledgement --- p.iv / List of Figure and Table --- p.vii / Paper published --- p.xi / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Overview on Near Eye Display (NED) --- p.1 / Chapter 1.2 --- Literature Review on HMD --- p.1 / Chapter 1.3 --- Motivation and Research Objective --- p.7 / Chapter 1.4 --- Thesis Outline --- p.8 / Chapter Chapter 2 --- Fundamental Design Concept --- p.9 / Chapter 2.1 --- Prism --- p.9 / Chapter 2.2 --- Convex Lens --- p.11 / Chapter 2.3 --- Combination of Convex lens and Regular Prism --- p.12 / Chapter Chapter 3 --- Optical Design Analysis by Software Package --- p.16 / Chapter 3.1 --- Surface Alignment --- p.16 / Chapter 3.2 --- Distortion --- p.18 / Chapter 3.3 --- MTF --- p.19 / Chapter 3.4 --- Image Simulation --- p.20 / Chapter 3.5 --- Aberration analysis --- p.21 / Chapter 3.6 --- Aspherical surface --- p.22 / Chapter Chapter 4 --- Design Principle and Procedure --- p.26 / Chapter 4.1 --- Basic Criteria --- p.26 / Chapter 4.2 --- See-throughPurpose --- p.27 / Chapter 4.3 --- Material --- p.28 / Chapter 4.4 --- SurfacesAlignment --- p.29 / Chapter 4.5 --- Compensator --- p.30 / Chapter 4.6 --- Angle Alignment --- p.30 / Chapter Chapter 5 --- System Efficiency --- p.32 / Chapter 5.1 --- System Efficiency --- p.32 / Chapter 5.2 --- System Analysis --- p.35 / Chapter Chapter 6 --- Prototype Fabrication and Testing --- p.38 / Chapter 6.1 --- Display System --- p.38 / Chapter 6.2 --- Monocular Configurations --- p.39 / Chapter 6.3 --- Prototypes Building --- p.40 / Chapter 6.4 --- Advantages --- p.54 / Chapter 6.5 --- Limitation --- p.54 / Chapter Chapter 7 --- Conclusions and Future Work --- p.55 / Chapter 7.1 --- Conclusions --- p.55 / Chapter 7.2 --- Future work --- p.55 / Reference --- p.57 / Appendix --- p.60 / Chapter Appendix 1 --- Background Theory --- p.60 / Chapter A1.1 --- Optical Theory --- p.60 / Chapter A1.2 --- Matrix Method --- p.65 / Chapter A1.3 --- Human Vision --- p.66 / Chapter Appendix 2 --- Simulation of reflection --- p.67 / Chapter Appendix 3 --- Aberration analysis of prisms --- p.70 / Chapter Appendix 4 --- Specification --- p.71
700

Alexander Scriabin's style and musical gestures in the late piano sonatas : Sonata No.8 as a template towards a paradigm for interpretation and performance

Seah, Stefanie Huei-Ling January 2011 (has links)
Alexander Scriabin's piano sonatas are largely regarded as the most significant works in the genre since Beethoven. They outline the development of his compositional style from the youthful Chopinesque works, to his mature, idiosyncratic post-tonal offerings. According to his close friend, biographer, and critic Leonid Sabaneyev, despite Scriabin's philosophy suffering “from too many manifest faults”, his late music is “incomprehensible and incomplete” when “severed from his philosophy”. Consequently, this treatise focuses on Scriabin's unique compositional voice through an examination of his idiosyncratic musical gestures, and the points of their interaction/intersection with his eclectic philosophizing. Recognizing the absence of a substantial interpretive system that reconciles Scriabin's music with his philosophical outlook in the available Scriabin-scholarship, this dissertation investigates the impact of his mystical beliefs upon his compositional style. This is largely achieved through the identification and scrutiny of symbolic gestures in his idiosyncratic pianistic style. Part 1 constitutes the examination of Scriabin's symbolic gestures that routinely feature in his late works: unity, summons, light, flight, occult, resonance, sensuality, eroticism, ecstasy, and transformation/dissipation. Part 2 discusses Sonata no.8, which stands to benefit the most from a gestural reading, due to the near absence of the composer's customary vivid French annotations. A brief discussion regarding issues of interpretation and performance of that sonata and Scriabin's late keyboard works completes this dissertation. The investigative method outlined above, in synergy with the composer's complex beliefsystem, develops a new gestural framework for perceiving and interpreting Scriabin's work; one that blurs the conventional distinctions between musicologist and performer, enabling informed conceptualizations and gestalt performances of these ‘symbolist' works. Sonata No.8 is used as a matrix upon which this theoretical approach is applied. Through relative comparisons and references to the other late sonatas, the Eighth is proffered as an interpretive model upon which analogous interpretations may be based.

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