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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.
11

Superembeddings, Partial Supersymmetry Breaking and Superbranes

Paolo Pasti, Dmitri Sorokin, Mario Tonin, sorokin@pd.infn.it 10 July 2000 (has links)
No description available.
12

Experimental study on the wave energy dissipation by a submerged breakwater

Wu, Yi-Ping 02 September 2010 (has links)
In this thesis,I discuss the wave pass on submerged bweakwater,and theheight of submerged breakwater,different slope of submerged breakwater with breaking wave relations.I do experiment to find the regular between breaking wave and the design of submerged breakwater.I use different submerged breakwater,there are two slope.There are 1/2 and 1/5.The height of submerged breakwater is 45 cm,the wide of submerged breakwater is 75 cm.the water deep is from 50cm to 90 cm,Wave cyclical is from 1.2 sec to 2.7 sec,I use H L to choose wave height,and save the data of incident wave.and then I analysis the data to get t K and energy.I also memorize the site of breaking wave and breaking type. From the experiment ,we know that wave do not be broken, be broken, and the regular of breaking wave and breaking type ,so we can use the regular to design the height of submerged breakwater, the slope of submerged breakwater. So we can use the least costs to protect the seacoast. When we know local wave condition, we can design the height of submerged breakwater to break wave that is dangerous for seacoast ,or we want to break wave when the wave height at 1 m or 2 m or others design the height of submerged breakwater. When £m^2h/g is between 0.3 and 2.5,we can find that when R/H0¡¦ is smaller than 1,the wave will break¡CWhen wave break bysubmerged breakwater ,we can find the slope of 1/5 is better than the slope of 1/2 to reduce the wave.Both slope of 1/2 and slope of 1/5 are effective to reduce wave energy at Hi/R=2.
13

Dynamics of Wave Breaking at a Coastal Sea Wall

Antoine, Arthur L. 2009 December 1900 (has links)
Structural designs barely consider the dynamic scenario of a well-developed impinging wave hitting the structure. The usual area of focus is on static and stability factors (e.g. drag, inertia, resistive forces related to weight, buoyancy, sliding etc). Even the "Factor of Safety" which is regularly used in designs to account for unknown and/or unforeseen situations which might occur implies a degree of uncertainty about the dynamic scenario of breaking waves in the coastal environment. In the present study the hydrodynamics of a coastal structure-turbulent bore interaction was studied by examination (two-dimensional) of the singular case of a plunging breaking wave forming a well developed turbulent bore which impacted on a model sea wall structure. The turbulent bore impact event was found to display similar characteristics to the impact event of other wave shapes, in particular that of a plunging breaker. Examination of the impact event confirmed the conversion of nearly all horizontal velocity to vertical velocity during the "flip through" event. In accordance with theoretical expectations the location of maximum pressure was found to occur just below the still water level (SWL). Resulting pressure data in the present study consisted of two blunt spikes as opposed to the "church-roof" (high spike) shape seen in other results. The shape of the pressure data was attributed to the following: firstly, to the initial impact of the protruding jet of the breaking wave which causes the first maxima, secondly, to the sensor encountering the bulk of the entrapped air hence causing the drop in pressure between the blunt spikes and lastly, to the inherent hydrostatic pressure combined with the compression of the entrapped air bubbles, by the subsequent forward motion of the water within the wave, which causes the second maxima. The point of maximum pressure was found to always be within the second maxima. Observation of the turbulent bore-structure interaction showed that the consequential maximum pressure was a direct result of the compression of entrapped air by the weight of the water in the wave as it continued forward onto the structure combined with the inherent hydrostatic pressure of the wave. The project was conducted in an attempt to contribute to the vast knowledge of coastal structure-wave interactions and to add to the understanding of the physics and characteristics of breaking waves. Whilst numerous studies and experiments have been carried out on the phenomenon of breaking waves by previous researchers the current project highlights the advent of new equipment and technological advances in existing methods.
14

Computer simulation of ice breaking by explosion and impact

Mansour, Ahmad Mansour Adel. January 1982 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1982. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
15

Proposed control system for ice-transiting ship

Kashima, Tadashi. January 1984 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1984. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
16

Supersymmetry Breaking from Holography to Colliders

Redigolo, Diego 08 September 2014 (has links)
We investigate several aspects of four dimensional supersymmetric gauge theories with the minimal amount of supercharges both from the theoretical and the phenomenological view point. On the theoretical side we investigate the behavior of two-point correlators of short multiplets for vacua that spontaneously break supersymmetry. The main goal is to build up an exhaustive description of the supersymmetry breaking dynamics that it is easily extendable to strongly coupled gauge theories. When strong coupling is involved we study the behavior of two-point correlators by means of AdS/CFT techniques building up models of strongly coupled hidden sectors that break supersymmetry and can be described holographically by gauged supegravity in five dimensions. These hidden sectors have also some phenomenological interest in particle physics beyond the Standard Model since they can be used as supersymmetry-breaking sectors in models where the breaking of supersymmetry is mediated by gauge interactions. On the more phenomenological side we study how the Higgs mass requirements constraints gauge mediation models and what could be possible interesting signatures of these scenarios at LHC. / Doctorat en sciences, Spécialisation physique / info:eu-repo/semantics/nonPublished
17

Habit Reversal in the Hooded Rat as a Function of ECS and the "Complexity" of the Task

Morosko, Thomas E. January 1962 (has links)
No description available.
18

The Effect Of Wave Breaking On The Performance Of Tuned Liquid Dampers

Omar, Mohamed 06 1900 (has links)
An in-house numerical model developed at McMaster University was used in this research to investigate the effect of the wave breaking on the performance of Tuned Liquid Damper (TLD). In this model, the Volume Of Fluid VOF method was used to construct the free surface and the surface tension was taken into consideration to evaluate the wave breaking. The model was implemented on incompressible, 2D flow water within the TLD that was harmonically excited. . The ability of the TLD to cancel out the external excitation was examined via damping effectiveness of the TLD. The damping effectiveness is calculated as the ratio of the net energy experienced by the TLD to the input excitation energy; both energies were calculated as the area under the force-displacement curve. The investigation of the effect of the wave breaking was done through changing the fluid height ratios, amplitude and frequency ratios. The fluid height ratio was changed as h/L= 0.5, 0.35, 0.125 which is above and at and below the critical fluid level for wave breaking occurrence respectively. The critical height is defined as the height at which the waves start to break. It was found that at high fluid ratios wave breaking did not occur, in contrary, at critical level wave breaking did occur and even more breaking waves recorded to have taken place at much lesser levels. The effect of the fluid height ratio on the damping effectiveness of the TLD was investigated, it was seen that the damping effectiveness of the TLD improves as water level becomes shallower. The amplitude ratio was also examined; the behavior of the TLD in general did not change i.e. increasing the amplitude enhances the damping of the TLD. The frequency ratio range was selected to cover the near-resonance region. It was found that the TLD damps most excitation close to the resonance. The wave breaking occurrence was assured via the free surface visualization for several cases and found in agreement with different wave breaking shapes reported experimentally. / Thesis / Master of Applied Science (MASc)
19

Effect of rest-breaking and fruit thinning treatments on reproductive development in apple

Sagredo, Karen X. 12 1900 (has links)
Thesis (PhD(Agric) (Horticulture))--Stellenbosch University, 2008. / Lack of winter chilling is a major problem in producing temperate-zone fruit in warm climates. Delayed foliation and protracted bud burst and flowering are the main problems necessitating artificial means to break dormancy. In South Africa (SA), most apple production areas receive insufficient winter chilling, and an annual application of rest breaking (RB) agents is included as standard practice. The most used RB agent in SA was dinitro-o-cresol (DNOC) but its use was discontinued. Hydrogen cyanamide (HC) became the replacement. It has been effective in apple, but variable effects on fruit set, blossom, yield and fruit quality have been reported. Thidiazuron (TDZ) has also shown the ability to break dormancy in apples. Another important practice in apple production is chemical thinning (CT). However, results are highly influenced by the type of chemical, weather conditions, cultivar and blossom pattern. With the increasing efficacy of RB and by identifying its effects on vegetative and reproductive development, it will be possible to determine more effective chemical thinning treatments. The objective of this study was to determine appropriate RB treatments for apple trees in a warm winter climate, identifying their effect on vegetative and reproductive development and the influence on CT efficacy. The research was performed in the Elgin area (34°S, 300 m) SA, over a period of three years, on ‘Golden Delicious’ and ‘Royal Gala’. In evaluating the effect of different HC concentrations and oil, no synergistic or antagonistic effects were observed on budburst and yield. Mineral oil at 4% plus 1 to 2% Dormex® combined were sufficient to break dormancy. Dormex® at 4% (2.08% HC) reduced fruit set and yield. In general, the rest breaking treatments (DNOC, HC and TDZ) enhanced the final vegetative bud burst compared to the control, while reproductive bud burst in 2002 and 2003 was not significantly influenced. The treatments compressed and advanced flowering periods, but this effect was not always evident when the spring was warm. The treatments synchronised flowering on the tree and between the two cultivars. The mixture of 0.245% HC and 4% oil was less effective in terms of increasing bud burst in ‘Royal Gala’ compared to other rest-breaking treatments. The mixture of 0.49% HC and 4% oil effectively compressed and synchronised flowering in ‘Golden Delicious’. TDZ-oil used at the lower rates also increased bud burst and concentrated flowering. However, it appears that after a cooler winter, higher rates could result in an exacerbated bud burst effect with excessive vegetative growth. The rate and timing of TDZ-oil application influenced the reproductive development of apples and therefore fruit quality. In ‘Golden Delicious’ increased fruit set, number of seeds, and reduced fruit russeting appear as beneficial results of TDZ-oil, whereas fruit set and russeting was not affected in ‘Granny Smith’. TDZ-oil, when applied late and at increasing rates, led to an increase in the malformation of calyx cavities, especially when chemical thinning was performed using the cytokinin-like compound benzyladenine. The effect seemed to be cultivar specific, with ‘Golden Delicious’ being the most severely affected. Increased return bloom in response to late TDZ application in ‘Golden Delicious’ and ‘Royal Gala’ appeared to be beneficial.
20

3-D wave-induced nearshore circulation model

Lee, Kwang Soo January 1998 (has links)
No description available.

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