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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.
131

The use of technology in meeting science reform criteria: Can web-based instruction promote scientific literacy?

Vogt, Karen Fay 01 January 1999 (has links)
Science educators are currently facing the challenge of reforming the practices of science education. Publications of various science and educational organizations have established new criteria for accomplishing this goal. The new goal of science educators is scientific literacy for all.
132

Analýza tepelné spotřeby objektu / Analysis of Heat Energy Consumption of Buildings

Houzar, Tomáš January 2017 (has links)
Master’s thesis is focused on analysis of thermal consumption in the buiding. This work describes current state of family house and possible suggestions for heating and water heating. Part of solution is created program, which supposed to serve as universal calculation program for design and economic evaluation of suggested solar systém and allows a comparison between commonly used sources for heating and water heating.
133

Měření a regulace počítačem řízených solárních systémů: Vizualizace energetických systémů / Measuring and regulation of computer controlled solar systems: Vizualization of energetic systems

Vlčnovská Kotlíková, Silvie January 2008 (has links)
This work is oriented on study and evaluation of performance of real operating solar system. There was made analysis of actual technological unit and there was suggested mode of measuring of nodal parameters. There was made interconnection between the head operating unit of the solar system and the web server. And there was prepared software for grafical image of time and temperature dependence and for data transfer to ready web application. It primarily talks about increase of efficiency of real technological unit through regulating of parameter that is using up of accumulated energy.
134

Vyhodnocení ekonomické efektivnosti solárního systému / Analysis of the economic efficiency of a solar system

Mikl, Antonín January 2009 (has links)
The Master’s thesis deals with the processing of solar thermal systems for heating hot water, outdoor swimming pool and heating selected house. Introduces us how we can use the sun for the production of thermal energy through solar collectors. Furthermore, the basic components of the solar system and the types of collectors used. After this summary on the present state be the calculation of the system and fixing the price of the investment. The economic part of the evaluate if this system to invest, eventually appoint a return on investment.
135

Energetické hodnocení obytných budov / Energy Evaluation of Residential Buildings

Fojtů, Pavel January 2013 (has links)
This master thesis offers two cost-saving measures to reduce the energy consumption of a residential building. These measure include insulation of the building envelope, domestic hot water by solar colectors and heat recovery.
136

Návrh otopného systému pro nízkoenergetický rodinný dům / Design of heating system for low-energy family house

Kytýrová, Zdeňka January 2008 (has links)
This diploma thesis deals with the design of a heating system for a "low-energy" house. It is conceived as a low temperature system using a combination of radiators and underfloor heating. The design is supplemented with a calculation of heat loss, a proposal of needed components, a scheme of the system and means of regulation. The second part solves the heat source selection. A solar system with vacuum tubes is used as the primary source. The second one is an electrical water heater located in the accumulation reservoir for the hot domestic water. Necessary calculations for the design of the solar system, together with a scheme and means of regulation, are enclosed in this section.
137

Návrh solárního ohřevu vody a solárního přitápění v rodinném domě / Design of a solar space and DHW heating system for a detached dwelling

Čukat, Stanislav January 2012 (has links)
The master’s thesis deals with the design of solar assisted space heating and domestic hot water (DHW) heating in a detached single family dwelling. The thesis contains the heating load calculations as well as the calculation of the energy consumption for space and DHW heating. The thesis also contains the actual design and sizing of the heating system including the drawings. A simulation of solar heating was carried out with the use of the TRNSYS simulation tool in order to assess the yield of the solar heating system.
138

Heating of building with almost zero energy consumption / Heating of building with almost zero energy consumption

Kubátová, Anna January 2012 (has links)
The aim of the thesis is to model energetic needs for heating and temperatures progress in the building with almost zero energy consumption. The part of the work is the economical and energetic comparison. Proposed systems are based on a knowledge of active houses.
139

Deployment, Management, & Operations of Internet Routers for Space-Based Communication

Sims, Zack A. 25 August 2015 (has links)
No description available.
140

Europa's Lyman-Alpha Shadow on Jupiter

Ferm, Johan January 2020 (has links)
Europa is one of the most interesting satellites in the solar system in the search ofextra-terrestrial life, as it harbours an interior water ocean under its icy surface. Watervapour in Europa’s atmosphere has been previously observed, suggesting water plumeeruptions from the surface. These plumes could potentially originate from the subsurfaceocean, and as such contain ocean constituents that can be examined in orbit. Twoobservations of Europa’s far-ultraviolet shadow on Jupiter were made by the HubbleSpace Telescope in 2018 and 2019. It was observed in Lyman-α (1 216 Å), a spectral lineof hydrogen. This study investigates the imaged Lyman-α shadow in search of potentialplumes at the shadow limb. Examining the shadow instead of the moon itself is a newmethod of remotely studying the Europan atmosphere. Forward modelling is applied tocreate artificial images that are compared to the observations. Any anomalies aroundthe shadow limb are then analysed and evaluated for their statistical significance. Twonoteworthy outliers are found at the limb (one on each occasion) corresponding to H2Oline of sight column densities of 3.07×1017 cm−2 and 4.72×1016 cm−2, for the 2018 and2019 observation, respectively. They are not significant however, as they lie within threestandard deviations from the expected value (< 3σ). An upper limit on what columndensity is detectable in the data is computed, yielding 6.71×1016 cm−2 (using only 2019data due to a weak signal on the 2018 occasion). A constraint on the maximum possibleH2O column density at Europa is thus provided. The new method is shown to be usefulfor the intended purpose and could potentially be applied on other icy moons. / Europa är ett av solsystemets mest intressanta objekt i jakten på utomjordiskt liv, dådet finns ett hav av vatten under månens isiga yta. Vattenånga har tidigare observeratsi Europas atmosfär, vilket kan tyda på vattenplymer som skjuts ut från ytan i kraftigautbrott. Dessa plymer kan möjligtvis ha sitt ursprung i månens inre hav, de kandärför möjliggöra en analys av havsvattnets beståndsdelar i omloppsbana. Europasultravioletta skugga på Jupiter observerades vid två tillfällen 2018 och 2019, av HubbleSpace Telescope. Observationerna gjordes i Lyman-α (1 216 Å), en spektrallinje hos väte.Denna studie undersöker den avbildade skuggan i Lyman-α för att söka efter potentiellavattenplymer vid skuggans rand. Att undersöka skuggan istället för själva månen är en nymetod för att studera Europas atmosfär genom fjärranalys. Metoden forward modellinganvänds för att skapa artificiella bilder, som jämförs med observationerna. Eventuellaavvikelser som hittas runt skuggans rand analyseras sedan och deras statistiska signifikansutvärderas. Två anmärkningsvärda avvikelser kan hittas vid randen (en vid varjeobservationstillfälle), som motsvarar H2O-kolumndensiteter på 3.07 × 1017 cm−2 och4.72 × 1016 cm−2, för 2018-observationen respektive 2019-observationen. Densiteternaär dock inte signifikanta, då de ligger inom tre standardavvikelser från deras förväntadevärden (< 3σ). Istället beräknas en övre gräns för vilken kolumndensitet som kandetekteras i datan, vilket ger 6.71 × 1016 cm−2 (där endast 2019-data används på grundav en svag signal hos 2018-observationen). Den högsta möjliga H2O-kolumndensitetenkan således begränsas. Den nya metoden visar sig vara användbar för det tänkta syftetoch kan eventuellt appliceras på andra ismånar.

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