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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.
31

Diffraction and direct methods for surface structure determination /

Chu, Tsui-ping. January 1997 (has links)
Thesis (M. Phil.)--University of Hong Kong, 1997. / Includes bibliographical references.
32

Low energy electron diffraction from SI(111)7X7 and ultrathin films on substrate crystals /

Lai, Wai-kong, Pan. January 1999 (has links)
Thesis (M. Phil.)--University of Hong Kong, 1999. / Includes bibliographical references (leaves 107-108).
33

Temperature dependence of the low-energy electron diffraction from silver

Jones, Edwin R., January 1965 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1965. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
34

Climate-responsive design for non-domestic buildings in warm climates : optimisation of thermal mass for indoor cooling

Diaz, Camilo January 1994 (has links)
The present investigation focuses on the study of the thermal inertia of buildings examining the extent to which the envelope and internal components can moderate their internal climate. Especial emphasis is given to the analysis of thermal mass effects in conditions of overheating in buildings with predominantly day-time occupancy schedules such as offices and mixed use buildings. The thesis comprises three parts. The first part discusses the principles and definitions of thermal inertia identifying a number of aspects which are relevant to the thermal performance of buildings. A review of the physical principles and parameters for quantification of heat storage in building elements is also included. The second part presents the results obtained from a series of field experiments carried out in six buildings in different locations to observe the thermal reaction on their internal spaces according to the particular thermal mass characteristics of each case. The third part is devoted to the analytic work by means of parametric studies and by comparing the field experiments findings with computer simulation results and exploring additional aspects of thermal mass effects. The analytic studies included the application of the diurnal heat capacity method for the calculation of internal temperature swings obtaining results in close agreement with both SERI-RES simulations and field measurements. A calculation worksheet is proposed to facilitate the internal swing calculations. Finally, the conclusions obtained from the results were used to define a series design measures aimed at the improvement of indoor thermal conditions by the optimisation of the effect of thermal mass of buildings in warm environments.
35

Lokalizační systém / Localization system

Chlad, Miloslav January 2017 (has links)
The intent of this master’s thesis is to look for the best solution of finding lost items of everyday use. Described solution is based on GPS for outdoor and Bluetooth Low Energy for indoor localization. User of this system will be able to find his/her lost items using smartphone application.
36

Influence of a low energy diet within Berkshire genetics on associated effects of growth, composition, and quality

Bishop, Megan Josephine 17 March 2011 (has links)
No description available.
37

Development of a Low-Energy Ion Scattering Surface Analysis System Using a Time-of-Flight Method / Development of an Ion-Scattering System

Cervin, Andrew Claude January 1981 (has links)
An ion scattering surface analysis system using TOF energy-analysis of the scattered ions was improved with a duoplasmatron ion source and new data-handling electronics. The new source gave greater beam current and stability. The new electronics were: a timing filter amplifier and constant fraction discriminator. Much work was done on alignment of the sample in the beam and reduction of the spot size. To add to the flexibility of the beam guidance system a new pair of steering plates was added. Some of the test spectra are presented to show the operation of the system. Relevant material on various aspects of the system are presented in the appendices. / None / Master of Engineering (ME)
38

Mobilsportsensor : Utvecklingsplattform för att kvantifiera träning / Mobile Sport Sensor : Development Platform to Quantify Training

Lindgren, Carl, Jakum, Andreas January 2020 (has links)
Simning är en sport där små marginaler har stor inverkan på resultatet. I OS-finalen 2008 vann Michael Phelps över Milorad Čavić med en hundradels sekund. För att få marginalen på sin sida behöver simmaren träna otaliga timmar. I dagsläget har Kungliga Tekniska Högskolan inte en bra prototyp för att testa, utvärdera och mäta en simmares träning. Att kontinuerligt under ett helt träningspass få mätvärden som kan användas för att förbättra simtekniken skulle kunna ge en stor fördel. Målet med det här examensarbetet är att utvärdera möjligheten att utveckla en metod för att mäta dessa värden. Metoden som valdes var att med en IMU och mikrokontroller mäta rörelser. En jämförelseanalys gjordes mellan mikrokontrollers för att ge plattformen bästa utvecklingsmöjligheter. Efter resultatet från jämförelseanalysen införskaffades de två olika mikrokontrollers som hade störst potential och dessa två jämfördes vidare. Därefter utvecklades flera möjliga designer för plattformen med störst potential som kan användas för att kvantifiera simträning. Resultatet blev två funktionella protyper som uppfyllde de krav som ställdes. Framtida utveckling skulle vara att testa och utvärdera plattformarna vidare och hitta andra sporter och användningsområden. / Swimming is a sport where small margins can have a big impact on the result. In the 2008 Olympic finals Michael Phelps won over Milorad Čavić by one hundredth of a second. To get the margin on their side, the swimmers need to practice countless hours. Currently, the Royal Institute of Technology does not have a good prototype for testing, evaluating, and measuring a swimmer's training. Continuously getting measured values during an entire training session that can be used to improve a swimming technique could provide a great advantage. The aim of this thesis is to evaluate the possibility of developing a method for measuring these metrics. The method chosen was to measure movements using an IMU and microcontroller. A comparison analysis was made between microcontrollers to provide the platform with the best development opportunities. Following the results of the comparison analysis, two different microcontrollers with the greatest potential were acquired and these two were further compared. Subsequently, several possible designs were developed for the platform with the greatest potential that can be used to quantify swim training. The result was two functional prototypes that met the requirements. Future development would be to test and evaluate the platforms further and find other sports and areas of use.
39

Accelerated optimisation methods for low-carbon building design

Tresidder, Esmond January 2014 (has links)
This thesis presents an analysis of the performance of optimisation using Kriging surrogate models on low-carbon building design problems. Their performance is compared with established genetic algorithms operating without a surrogate on a range of different types of building-design problems. The advantages and disadvantages of a Kriging approach, and their particular relevance to low-carbon building design optimisation, are tested and discussed. Scenarios in which Kriging methods are most likely to be of use, and scenarios where, conversely, they may be dis- advantageous compared to other methods for reducing the computational cost of optimisation, such as parallel computing, are highlighted. Kriging is shown to be able, in some cases, to find designs of comparable performance in fewer main-model evaluations than a stand-alone genetic algorithm method. However, this improvement is not robust, and in several cases Kriging required many more main-model evaluations to find comparable designs, especially in the case of design problems with discrete variables, which are common in low-carbon building design. Furthermore, limitations regarding the extent to which Kriging optimisa- tions can be accelerated using parallel computing resources mean that, even in the scenarios in which Kriging showed the greatest advantage, a stand-alone genetic algorithm implemented in parallel would be likely to find comparable designs more quickly. In light of this it is recommended that, for most lowcarbon building design problems, a stand-alone genetic algorithm is the most suitable optimisation method. Two novel methods are developed to improve the performance of optimisation algorithms on low-carbon building design problems. The first takes advantage of variables whose impact can be quickly calculated without re-running an expensive dynamic simulation, in order to dramatically increase the number of designs that can be explored within a given computing budget. The second takes advantage of objectives that can be !Keywords To Be Included For Additional Search Power: Optimisation, optimization, Kriging, meta-models, metamodels, low-energy design ! "2 calculated without a dynamic simulation in order to filter out designs that do not meet constraints in those objectives and focus the use of computationally expensive dynamic simulations on feasible designs. Both of these methods show significant improvement over standard methods in terms of the quality of designs found within a given dynamic-simulation budget.
40

Direct determination of the 6H-SiC(0001)-3X3 and 6H-Sic(0001)-[square root] 3 x [square root] 3 surface reconstruction by LEED Pattersonfunction

Lau, Wai-ping, 劉偉平 January 2004 (has links)
published_or_final_version / abstract / toc / Physics / Doctoral / Doctor of Philosophy

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