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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.
281

A re-examination of the origins of Romani

John, Vijay George 15 April 2014 (has links)
Romani Studies as an academic discipline emerged in the 18th century with scholars such as Rüdiger (1782) and Grellmann (1783). At that time, two main hypotheses regarding the origin of the Roma formed that, in some variation, still have their adherents today. Rüdiger argued that the Roma’s ancestors left India because of invading armies, whereas Grellmann argued that they were social outcasts. This thesis argues in support of a military origin of the Roma and a koïné origin of the Romani language by bringing together linguistic, sociohistorical, and genetic evidence. / text
282

Wear and Contact Phenomena in Existing and Future Large-Scale Chemical Mechanical Planarization Processes

Jiao, Yubo January 2012 (has links)
This dissertation presents a series of studies with regards to wear and contact phenomena in existing and future large-scale chemical mechanical planarization (CMP). They are also evaluated with the purposes of reducing cost of ownership (COO) and minimizing environmental impacts. The first study is performed to investigate the effect of retaining ring slot design, material and temperature on pad wear during interlayer dielectric CMP. During polishing, friction is generated at the retaining ring-pad interface resulting in pad wear. Three retaining rings are used in this study and the results show that the retaining ring material and temperature have significant impacts on the pad wear rate. In the next study, a custom-made sample holder is designed to heat pad sample. Pad surface contact area and density are measured at three different temperatures using laser confocal microscopy to illustrate the effect of temperature on the mechanical contact during CMP. In the third study, the tribological, thermal and kinetic attributes of 300 mm copper CMP process are investigated. The current state-of-the-art IC manufacturing factories have migrated from 200 mm wafer processes to 300 mm to reduce manufacturing COO and increase throughput. In this study, a two-step modified Langmuir-Hinshelwood model is used to simulate copper removal rate as well as chemical and mechanical dominance during CMP. The fourth study evaluates the relationship between planarization and pad surface contact area and micro-topography using laser confocal microscopy. Results of confocal microscopic analysis are correlated with polishing performance in terms of coefficient of friction, removal rate, time to clear, dishing and erosion. As Ti has recently regained attention in copper barrier applications, the effect of temperature during Ti CMP is investigated in another study to provide fundamental understanding of Ti removal mechanism. The last contribution of this dissertation involves a study on 450 mm CMP process. An existing 300 mm CMP tool is modified to polish both 300 and 450 mm wafers to demonstrate experimentally whether any differences exist in the tribological and thermal characteristics of the two processes, and from that, to infer whether one can expect any removal rate difference between the two systems.
283

Contact Representations of Graphs in 2D and 3D

Alam, Muhammad Jawaherul January 2015 (has links)
We study contact representations of graphs in the plane and in 3D space, where vertices are represented by polygons or polyhedra and each edge is represented by a common boundary between two polygons or polyhedra. In the weighted version of the problem, we find contact representations with the additional restriction that the areas for the polygons or the volumes for the polyhedra realize some pre-specified value for the vertices. We address different variants of the problem depending on the types of polygons or polyhedra (convex or non-convex, axis-aligned or not), types of contacts (proper contacts with common boundaries of non-zero lengths in 2D or non-zero areas in 3D or improper contacts where common boundaries of zero lengths or areas are allowed), and whether holes are allowed in the representation or not. In the plane we mainly focus on the weighted version of the problem. We find optimal (in terms of polygonal complexity) contact representations for planar graphs (both for axis-aligned and non-axis-aligned polygons) and some subclasses of planar graphs. With non-axis-aligned polygons we show that non-convex polygons with 4 sides are sometimes necessary and always sufficient for proportional contact representation of a planar graph, when point contacts are allowed; otherwise for proper contacts 7-sided polygons are sometimes necessary and always sufficient. We give a linear-time algorithm in each case to compute the optimal representation. We also give quadratic-time algorithms to construct optimal proportional contact representations for (2, 0)-sparse graphs (with triangles for improper contacts and with convex quadrilaterals for proper contacts). For maximal outerplanar graphs proportional contact representation with triangles can also be computed in linear time. In case only axis-aligned polygons are used, we show that 8 sides are sometimes necessary and always sufficient for a planar graph. While we do not have a polynomial-time algorithm to construct such a representation, we give a linear-time algorithm to compute representation with 10-sided axis-aligned polygons. We also give linear-time construction algorithms for optimal proportional contact representations with 8-sided polygons for planar 3-trees and Hamiltonian maximal planar graphs, and with rectangles for maximal outerplanar graphs. For contact representation with 3D polyhedra, we consider both the weighted and the unweighted variants of the problem for both planar and non-planar graphs and have some preliminary results. We find several subclasses of planar graphs that have contact representations using cubes or proportional boxes. We also consider (improper) contact representations using tetrahedra, and show that planar graphs, complete bipartite and tripartite graphs, and complete graphs with at most 10 vertices have contact representations with tetrahedra. We also addressed variants of this problem using only unit regular tetrahedra or considering contacts only between apices of the tetrahedra or using both restrictions.
284

Pad-Wafer and Brush-Wafer Contact Characterization in Planarization and Post-Planarization Processes

SUN, TING January 2009 (has links)
This dissertation presents a series of studies relating to pad-wafer and brush-wafer contact characterization in planarization and post-planarization processes. These are also evaluated with the purposes of minimizing environmental impact and reducting cost of ownership.Firstly, a new method using spectral analysis based on real-time raw friction data is developed to quantify the total amount of mechanical interaction in the brush-fluid-wafer interface in terms of stick-slip phenomena in post-planarization scrubbing. This new method is remarkable from the standpoint of its potential to eliminate having to perform a multitude of experiments needed for constructing and interpreting Stribeck curves, and its application to processes where Stribeck curves fail to yield any useful data. Moreover, this method is applied to investigate the effect of brush roller design on scrubbing process and to analyze behaviors of eccentric brushes.In order to study pad-wafer contact in planarization processes, a mechanical characterization method (incremental loading test) is developed and applied to analyze different types of pads and pad surfaces subjected to various treatments. Along with optical interferometry and theoretical analysis, flow resistance due to pad land area topography can be estimated.The greatest contribution of this dissertation involves development of real pad-wafer contact area measurement technique using confocal microscopy. The real pad-wafer contact area is a difficult property to measure in planarization, yet it is a key feature to further understand the process. A custom-made sample holder with a sapphire window and a miniature load cell is used to collect confocal images at controlled values of down force.At last, the two newly developed techniques (incremental loading test and real pad-wafer contact area measurement using confocal microscopy) together with dual emission UV enhanced fluorescence imaging are utilized to investigate conditioning effects in planarization process.
285

Two roads - no exit : an in camera discourse on negotiations in North America today

McIntyre, Donald G. 11 1900 (has links)
This work is an interdisciplinary exploration of negotiations between the nations that make up Canada. It explores the disparity that remains between Aboriginals and non Aboriginals in Canadian North America at a systemic level. It will show that the postcolonial era is rampant with colonial doctrine and that these principles and policies maintain a dogmatic system that can not allow for the continued existence of Aboriginals as separate and distinct peoples. I will show my understanding and interpretation of an old Indigenous system and suggest ways in which aspects of this ancient system may be valuable in creating a coordination of world views that can allow for both factions to exist and prosper. I will specifically address how the differing world views that exist between Aboriginal and non-Aboriginal Canadians—and the inequality between these two groups of peoples—has been and remains infused in the negotiation process that these governments attempt to complete. The final aspect of this work will be a theatrical production piece that allows (in some small way) the traditional Indigenous approach to ‘law’ to be given equal weight as the Supreme Court in Delgamuukw suggests.
286

Įvairaus meistriškumo futbolininkų kontaktinių veiksmų rezultatyvumas / The results of contact actions of football players with different skills

Butkus, Darius 11 August 2011 (has links)
Taktiniai, tame tarpe dvikovos, puolimo ir gynybos veiksmai, yra vienas iš pagrindinių faktorių, įtakojančių galutiniam rungtynių rezultatui. Per ilgalaikį futbolo sporto šakos vystymosi laikotarpį keitėsi taktinės sistemos, puolimo ir gynybos akcentai, tobulėjo futbolininkų technika ir taktika. Mokslininkai savo tyrimais daug pasiekė didindami sportininkų morfofiziologines ir psichologines galimybes. Todėl gerėjant futbolininkų fiziniam parengtumui nepaprastai padidėjo žaidimo sparta. Futbolininkų taktinio parengimo lygis priklauso nuo to, kaip jie įsisavinę taktikos priemones, formas ir rūšis. Taktikos priemonės - tai visi technikos veiksmai ir jų atlikimo būdai, formos - individualūs, grupiniai, komandiniai veiksmai, rūšys - puolimo ir gynybos taktika, yra tyrinėta ir spręstina mokslinė problema. Tyrimo tikslas – stebėti ir analizuoti futbolininkų kontaktinius veiksmus įvairaus lygio rungtynėse, įvertinti jų efektyvumą. Buvo taikyti 4 tyrimo metodai: literatūros šaltinių analizė ir apibendrinimas, pedagoginis stebėjimas, palyginamoji analizė, matematinė statistika. Brazilijos r. dvikovų skaičius siekia iki 200, iš jų 103 pozityvios ir 97 negatyvios dvikovos. Efektyvumas 51.5 proc. Prancūzijos r. dvikovų skaičius siekia 233, iš jų 124 pozityvios ir 108 negatyvios dvikovos. Efektyvumas 53.2 proc. Lietuvos rinktinės dvikovų skaičius siekia 160, iš jų 76 pozityvios ir 84 negatyvios dvikovos. Efektyvumas 47 proc. FK „Ekranas“ komandos vidutinis dvikovų skaičius per rungtynes... [toliau žr. visą tekstą] / Tactical, including duel, attack and defence actions is one of the crucial indicators influencing the final result of a competition. In a long run of football development the tactical systems, attack and defence focuses has been changing, the techniques of football players improved. The scientists with their research works achieved a lot in increasing morpho physiological and psychological abilities. That is why when physical abilities of the football players improve, the speed of playing enlarged immensely. The level of tactical preparation of football players depend upon the possessing tactical tools, forms and kinds. Tactical tools are all technical actions and their ways of implementation, forms – individual, group, team actions, and kinds – attack and defence technique and all this makes the science scope which has to be analysed and solved. The aim of the analysis is to observe and analyse contact activities of football players at the matches of various level and to evaluate their efficiency. 4 methods of analysis were used: the analysis of literature sources and summarising, pedagogical observing, comparative analysis, mathematical statistics. . In the ranking of the world countries the number of combats reaches 200, out of it 103 are positives and 97 are negative ones. Brazil takes 51.5 pct. In the ranking of France countries the number of combats reaches 233, out of it 124 are positive and 108 are negative ones. Effectiveness takes 53.2 pct. The number of... [to full text]
287

Etorinių kontaktinių lęšių padėties ant akies stabilumo tyrimas / The investigation of toric contact lens position on the eye stability

Tekutienė, Vilma 21 August 2013 (has links)
Koreguoti kliniškai reikšmingą astigmatizmą būtina, nes visai nekoreguotas ar neteisingoje ašyje iškoreguotas astigmatizmas sukelia ne tik blogą matymą, bet ir astenopiją. Koreguoti kliniškai reikšmingą astigmatizmą būtina, nes visai nekoreguotas ar neteisingoje ašyje iškoreguotas astigmatizmas sukelia ne tik blogą matymą, bet astenopiją. Toriniai kontaktiniai lęšiai (TKL) suteikia galimybę labai tiksliai ištaisyti šią ydą, bet viena būtina sąlyga - jie turi būti stabilioje padėtyje. TKL stabilumas priklauso nuo vokų plyšio, ragenos formos, vokų prispaudimo jėgos, o taip pat nuo refrakcijos ydos dydžio ir astigmatizmo ašies. / N Scientific and Technical Progress century eyesight play an increasingly larger burden. To adjust clinically significant astigmatism is necessary, because completely uncorrected or wrong corrected axis of astigmatism cause not only poor vision, but asthenopia. Toric contact lenses (TKL) allows very precise remedy of this defect, but one necessary condition - they must be in a stable position. TKL stability depends on the eye crack opening, corneal shape, eyelid clamping force, as well as the refractive defect size and astigmatism axis.
288

Validation of a Dynamic Simulation of a Five Degree of Freedom Point Contact Joint

Knutson, Amanda 05 November 2007 (has links)
A new special case computer simulation to model the non-linear, three dimensional dynamic equations of motion of a five degree of freedom point contact joint has been developed and the functionality has been validated with data collected from a physical model. A system physically realistic to model was designed with sphere in sphere contact. A small outboard body articulates within a larger inboard spherical cut out body and springs help provide stability to the system by attaching the outboard body to the ground. The outboard body can move relative to the inboard body in both a rolling and sliding manner. The dynamic equations of motion were determined using Kane’s formulation and a numerical solution was attained through the implementation of a fourth-fifth order, variable time step, Runge-Kutta integrator. The positions of four markers, located on the outboard body of the system, were predicted in ground fixed coordinates by the solution routine. A physical model of the system was constructed and position locations of four markers located on the outboard body were captured by an Optotrak 3020 motion tracking system. Both static and dynamic experimental trials were performed and compared to the simulation. For one test case, the experimental data frequency of oscillation was found to be ωe = 2.33 Hz and the simulation frequency was found to be ωs = 2.37 Hz. Several sources for the discrepancies include viscous damping, a possible additional forcing function caused by lead wire sway, and neglecting the mass of the system’s springs. Coulomb damping was included in the simulation. / Thesis (Master, Mechanical and Materials Engineering) -- Queen's University, 2007-10-30 16:12:57.843
289

Albertans' preferences for social distance from people with mental illnesses or problems

Klassen, Amy Lynn Unknown Date
No description available.
290

Drop Removal from Solid Surfaces: Shedding and Evaporation

Chini, Seyed Farshid Unknown Date
No description available.

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