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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.
51

The Impact of a Sixth Grade Laptop Initiative on Student Attitudes Concerning Their Learning and Technological Competencies

Jordan, Jamie 01 May 2018 (has links) (PDF)
This research explored the impact of a sixth grade one-to-one laptop initiative on student attitudes about learning and technological competencies. The study compared student preintervention and postintervention survey data prior to and after a sixth grade laptop intervention initiative. The survey responses were divided into 5 dimensions (School Subject Attitudes, Teaching and Learning Preferences, Computer Use Perceptions, Technology Skills, and Personal Attitudes and Behaviors) on both pre- and postsurveys. District means were compared with preintervention and postintervention data, as well as the means from the 5 dimensions, using a one-sample t-test with a midpoint test value of 3 on a 5-point scale. Ninety students participated in the preintervention survey and 93 students participated in the postintervention survey across 3 schools. The findings indicated that there was a statistically significant difference in student responses in 4 of the 5 dimensions except Teaching and Learning Preferences. Overall the findings on the 2 dimensions related to technological competencies had statistically significant scores on the postintervention survey, whereas the findings on 2 of the 3 sections related to student attitudes about learning had statistically significant scores. In conclusion, generally the laptop intervention initiative had an overall positive impact on student attitudes and technological competencies. The researcher concluded that the timing of the postsurvey, as well as the research taking place during the first year of implementation could have had an impact on the Teaching and Learning Preferences results. Examining the impact of one-to-one initiatives on student attitudes about learning and technological competencies could support districts in making the decision of adopting this technology.
52

Control and monitoring of a BTES-system

Fjordestam, Patrik, Hansen, Sebastian January 2016 (has links)
During the summer excess energy is produced from solar heaters, this is not taken care of, and usually goes to waste. The base of the project is built on that you should take the excess energy during the warmest months of the summer and save the energy in boreholes in the ground, then during the colder months the energy can be used. The purpose of the project was to build a prototype for the control and monitoring of a system. With this project we want to present a solution to a prototype which can be used as a development platform for the client. Communication between the actuators, sensors and the controller is made via a CAN-bus. The temperature sensors uses a One-wire buss and its values are stored and can be shown on a website. The results show that the monitoring and control functions works. Theoretically, the prototype is designed to be expanded to a real application. / Under sommaren produceras överbliven energi från solvärmare, denna tas inte omhand utan går oftast till spillo. Projektets grund bygger på att ta den överblivna energin under de varmaste månaderna på sommaren och spara undan energin i borrhål i marken, för att sedan under kallare månader kunna använda detta. Syftet med projektet har varit att bygga en prototyp för styrning och övervakning av ett system. Med detta projekt vill vi visa en lösning på en prototyp som kan fungera som utvecklingsplattform för beställaren. Kommunikation mellan aktuatorer, sensorer och styrenhet görs via en CAN-buss. Temperaturensorernas använder sig av en One-wire buss och dess värden sparas och kan avläsas på en webbplats. Resultatet visar att övervakning av sensordata och reglering av aktuatorer fungerar. Teoretiskt sett är prototypen utformad för att expanderas till en verklig applikation.
53

Secure Remote Access to Telemetry: A Study in How to Allow Remote Access to Satellite Telemetry Data

McClinton, Arthur T., Jr. 10 1900 (has links)
ITC/USA 2009 Conference Proceedings / The Forty-Fifth Annual International Telemetering Conference and Technical Exhibition / October 26-29, 2009 / Riviera Hotel & Convention Center, Las Vegas, Nevada / The need to allow remote access to telemetry data from closed networks has long existed. To ensure the correct engineers are available for anomaly resolution, NOAA developed the Secure Remote Access Server (SRAS) to allow transfer of satellite telemetry to an external secure server. SRAS uses one-way links to protect the ground system and secure communications for all communications with the user. After the SRAS was developed, a similar system was developed to support file transfers. This paper provides an overview of these systems and lessons learned in the development of one-way fiber systems.
54

A theoretical analysis of the spin susceptibility tensor and quasiparticle density of states for quasi-one-dimensional superconductors

Vaccarella, Cawley D. 12 1900 (has links)
Thesis made openly available per email from author, 8-2-2015.
55

The unprecedented 'one country two systems': a comparative study of the 'high degree of autonomy' enjoyed by theHong Kong Special Administrative Region and the Macau SpecialAdministrative Region

Wong, Oi Yung, Lauretta., 黃愛容. January 2001 (has links)
published_or_final_version / Asian Studies / Master / Master of Arts
56

Single-crystal superconducting Pb nanowires and nanostructures

Yi, Ge January 1999 (has links)
No description available.
57

Reductive amination catalysed by iridium complexes

Ellis, Richard D. January 2001 (has links)
No description available.
58

Angle resolved studies of molecular photoionisation

Townsend, David Philip January 1999 (has links)
No description available.
59

Exciton relaxation dynamics in a one-dimensional semiconductor

XIAO, YEE-FANG 09 December 2013 (has links)
Carbon nanotubes are intriguing materials and extensively studied for both their fundamental properties and extraordinary performance in various applications during the last 20 years. They are extremely small in diameter, light in weight, sensitive to the environment, strong, and chemically stable. They can be either metallic or semiconducting depending on their species. The semiconducting species can absorb and emit light in a wide range of wavelengths. These outstanding properties of carbon nanotubes promise abundant applications that may be revolutionary. The opto-electronic behaviour of a single-walled carbon nanotube (SWCNT) is extremely sensitive to its physical structure and ambient environment. Structural defects and surrounding environment are extrinsic influential factors that often obscure the understanding of the intrinsic behaviour. Progress on SWCNT synthesis has been made continuously but not until the last 10 years, have single SWCNTs been isolated individually and from substrates so that their fluorescence can be detected. The fundamental science of an optically generated exciton (an electron-hole pair) in an ideal semiconducting SWCNT is not fully understood despite many studies of exciton behaviour using various optical approaches. The major challenge is controlling SWCNT sample qualities. SWCNT's fundamental properties, such as the absorption cross section, quantum efficiency, radiative and nonradiative lifetimes, remain under debate. Knowing the intrinsic SWCNT properties is essential to understand exciton transport and relaxation mechanisms. To minimize the extrinsic effects, we have selected high-quality unprocessed SWCNTs for investigation. Collaboration with Dr. P. Finnie and Dr. J. Lefebvre at National Research Council Canada, allow us to access pristine SWCNTs individually. Since the emission from a single SWCNT is low, it requires unconventional methods to measure the PL dynamics. Suggested by the results, exciton transport in a semiconducting SWCNT is diffusional at room temperature, with high diffusivity (130 -350 cm^2/s) and long diffusion length (1 - 5 µm). At lower temperatures, we observed a more efficient exciton-exciton interaction that suggests the contribution from hot excitons or a longer existence of delocalized excitons. Highly efficient exciton-exciton annihilation and long coherence time in a SWCNT are promising for making a single-photon source at near-infrared wavelength range and developing quantum computers. / Thesis (Ph.D, Physics, Engineering Physics and Astronomy) -- Queen's University, 2013-12-06 09:52:51.136
60

Material characterisation, testing, and modelling of finite element analysis of impact structures

Nichols, Rachel 10 1900 (has links)
Formula One race cars have to pass rigorous safety tests before they are allowed on track. This type of testing has been in place for years but the requirements for testing are continually increasing in order to reduce the amount of risk to the drivers’ safety during a race. The number of structures that need to be made and tested can quickly make this process an expensive one. Additionally, it is necessary to pass the mandated tests within a reasonable amount of time so as not to have an impact on the development on the rest of the car. There is a desire to reduce the number of structures needed for testing through finite element analysis (FEA), and as such, to reduce the time needed to pass the safety tests. FEA of laminated composites can be complex and is a balance between accuracy and the time it takes to find a solution. The current project looks into increasing understanding of the requirements for material characterisation, experimental impact testing, and explicit simulation of a carbon fibre fabric pre-impregnated with epoxy resin. Mercedes-Benz Grand Prix (MGP) Formula One Team has provided a pre-preg material for evaluation. Material experiments were performed per the American Society for Materials and Testing (ASTM) in order to find the tensile modulus, tensile strength, Poisson’s ratio, compressive strength, shear modulus, and shear strength of the material. Nine tubes were manufactured at MGP and tested in the drop tower at the Cranfield Impact Centre (CIC) ... [cont.].

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