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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.
161

Implementing a reusable design pattern Library in C#

Van Leeuwen, Alastair January 2013 (has links)
Design patterns in software systems are described as a universal reusable solution to a commonly recurring problem in software design. Design patterns were, however, not intended to be reusable in terms of code. A symptom of their non-reusability is the problems experienced with the way the implementation of design patterns negatively affects their traceability, maintainability and contribution to productivity. This thesis shows how design patterns can be elevated to a higher level of reusability. This work presents design patterns as reusable components that developers can use to implement solutions that utilise patterns, without having to implement a major part of a pattern’s structure and behaviour anew each time. A component is a reusable software section, with possible library classes, that is usually in source form. Previous research has shown that a high proportion of patterns (65%) can be “componentized” in Eiffel, which leads to the idea that a language supporting the same set of features would also have the same success in pattern componentization. This thesis has looked at the componentization of twelve design patterns in C#. The C# language has more advanced language features than Eiffel, including functional and dynamic language features and, as such, should lend itself better to pattern componentization than Eiffel does. The language features that are reviewed in this thesis are inheritance, design by contract™, attributes, method references (or delegates), anonymous functions, lambda expressions, mixins (or extension methods), duck typing, dynamic types and meta-programming. Each pattern’s reusable components are discussed in detail, including the success of the reusable component transformation. All the design patterns reviewed in this thesis could be transformed into fully or partially reusable components. Implementing design patterns using reusable library components is thus a step in the right direction in making design pattern implementations more traceable, reusable, maintainable and more productive. Other object-oriented languages implementing the same or similar language features as those reviewed in this thesis should have the same level of success in transforming design patterns into reusable components. / Dissertation (MSc)--University of Pretoria, 2013. / gm2014 / Computer Science / unrestricted
162

Attentional Window and Global/Local Processing

Schultz, Steven Peter 16 June 2016 (has links)
How does the focus of attention influence the encoding of information? Research has shown that size and allocation of the attentional window has an influence on what information is attended to or missed. The size-scale of features also effects processing of visual information. Previous research involving hierarchical stimuli suggests precedence for global features. In the present experiment, I investigated the influence of attentional window size on accuracy of encoding hierarchical stimuli at the global and local level. Here I introduce a new method for manipulating the size of the attentional window and for collecting unconstrained responses. At the start of each trial, observers tracked a dashed-line rectangular box, which either broadened or narrowed in size after onset. This sequence was immediately followed by a brief presentation of two hierarchical letters presented simultaneously on the left and right sides of the screen. The box preceding the hierarchical letters either broadened to a size large enough to include both letters at the global level, or narrowed to a size small enough to include a maximum of two letters at the local level at either side of the screen. Observers reported all letters they were able to identify. Results from two experiments indicate an overall precedence of global letters. However, a narrow attentional window reduced global precedence, as would be expected with more focused attention. The narrow windows also produced more same-side identifications of both global and local letters. The second experiment also showed that reducing the processing time decreased the global advantage.
163

Critical features and impacts of mathematics teacher professional development programs : Comparing and characterizing programs implemented at scale

Lindvall, Jannika January 2017 (has links)
The aim of this thesis is to contribute to the knowledge base on conceptualizations and impacts of teacher professional development (PD) programs. This is done by studying the case of two large-scale teacher PD programs. The first was mandatory for all public elementary school mathematics teachers in a larger Swedish municipality, and the second has been completed by 76% of all elementary school mathematics teachers in Sweden. In the municipality, and during the time frame in which this study was conducted, it was possible to make a comparison between teachers participating in different programs. Data on the programs’ impacts on teachers, instruction, and student achievement were gathered both immediately and one year after the teachers’ participation in one of them. In other words, the context of the study created an opportunity to respond to recent calls for studies that (a) examine the impacts of PD programs implemented on a larger scale, (b) adhere to PD programs’ impacts on teachers, instruction, and student achievement, (c) examine the sustainability of PD programs’ impacts, and (d) attend to variations within and between PD programs’ impacts. The results show that the studied programs are highly similar if characterized according to established research frameworks on what constitutes critical features of teacher PD. At the same time, they demonstrate different impacts, both between the programs and within them. These results suggested an elaboration of two of the five critical features of teacher PD: Content Focus and Coherence. Through the development and application of a more finely grained tool to characterize the programs’ Content Focus, differences between their characteristics were detected. Together with a systematic review of the PD research literature on Coherence, these results formed a basis for discussing plausible reasons for the difference in the programs’ impacts as well as elaborating on the critical features of Content Focus and Coherence. In summary, the thesis contributes: (a) empirical results in relation to large-scale teacher PD programs’ impacts; (b) methodological results in the form of tools for characterizing PD programs’ Content Focus and Coherence; and (c) theoretical results, as it examines established frameworks for characterizing teacher PD programs by using them in practice and, in light of the results, also suggests an elaboration of them. / I denna avhandling har två storskaliga kompetensutvecklingsprogram (KUP) för lärare använts som fall för att bidra till kunskap om kritiska aspekter av sådana program samt deras inverkan på lärare, undervisning och elevresultat. Det första programmet, Räkna med Västerås (RäV), var obligatoriskt för alla kommunala grundskolelärare som undervisade i matematik i kommunen. Det andra programmet, Matematiklyftet, har genomförts av 76 % av alla grundskolelärare i Sverige som undervisar i matematik. Under den tidsperiod som studien genomfördes var det möjligt att göra en jämförelse mellan programmen, då det vid tillfället fanns lärare i kommunen som antingen deltagit i RäV, Matematiklyftet, eller inget program alls. Data gällande programmens inverkan på lärare, undervisning och elevresultat samlades in både direkt och ett år efter lärarnas deltagande. Med andra ord gjorde studiens kontext det möjligt att svara upp mot nyliga uppmaningar om att det behövs fler studier som studerar: (a) inverkan av KUP som genomförts i större skala, (b) KUPs inverkan på lärare, undervisning och elevresultat, (c) KUPs långsiktiga inverkan, och (d) variationen mellan olika KUPs inverkan. Resultaten visar att de studerade programmen är ytterst lika om de karaktäriseras enligt etablerade ramverk om vad som utgör kritiska faktorer av KUP för lärare, samtidigt som de visar på olika inverkan på lärare, undervisning och elevresultat. I ljuset av dessa resultat föreslås en utveckling av två kritiska aspekter gällande KUP för lärare: innehållsfokus och samstämmighet. Genom att utveckla ett mer finkänsligt verktyg för att karaktärisera programmens innehållsfokus upptäcktes också skillnader mellan dem. Tillsammans med en systematisk litteraturöversikt av forskningslitteraturen kring ”samstämmighet” utgjorde dessa resultat en bas för att diskutera möjliga förklaringar till skillnaderna i programmens inverkan, samt en utveckling av de kritiska aspekterna innehållsfokus och samstämmighet. Sammantaget bidrar denna avhandling med: (a) empiriska resultat i förhållande till storskaliga KUPs inverkan, (b) metodologiska resultat i form av verktyg för att karaktärisera KUPs innehållsfokus och samstämmighet, och (c) teoretiska resultat då etablerade ramverk för att karaktärisera KUPs har studerats genom praktisk användning och i ljuset av resultaten föreslås även utvecklingar av dem.
164

Laser generation and applications of micron and submicron scale features on metals

Lloyd, Robert William January 2011 (has links)
This thesis describes the formation of and applications of self-assembled structures on metals. Primarily the focus of this PhD project is on the formation of surfaces structures on stainless steel (AISI 304) but other metals have been studied. Laser generated surface structures have been applied to the modification of wettability and reflectivity with a view towards developing these processes for industrial applications. Compared to conventional techniques for the modification of wettabililty, lasers offer the advantage of being a relatively simple technique for the modification of surface structure, reducing the need for complex processes. It is hoped that investigations into the reduction of surface reflectivity will have applications in the conversion of solar energy into useable power in the form of solar thermal energy. The production of self assembled structures is demonstrated using diode pumped solid state (DPSS) Nd:YVO4 lasers operating at wavelengths of 532 and 1064 nm. It is shown that the production of surface microstructures is highly dependant on the correct laser fluence and requires multiple pulses and processing passes. At 1064 nm wavelengths, it has been found highly reproducible surface structures can be formed by carefully controlling laser fluence and scanning speed while keeping the optical arrangement relatively simple. In addition to microstructure formation, the use of ultrafast femtosecond lasers, operating at 400 and 800 nm wavelengths has verified the production of laser induced periodic surface structures. Additionally, the stationary method used to produce these surfaces has been adapted to cover large surface areas with sub wavelength ripple structures with periods of ~295nm and 600nm. Applications of laser surface microstructures on metals have been studied in an effort to produce hydrophobic and superhydrophobic surfaces on metals. It has been found that the roughness change produced by laser processing induces composite wetting when water droplets are introduced to the surface. Contact angle measurements and small angle XRD analysis of laser processed stainless steel (AISI 304) have shown that surface wettability decreased over a period of approximately one month, leading to steady contact angles of over 140°. This is attributed to the formation of a magnetite (Fe3O4) oxide layer in the period after laser processing. The effect of surface microstructure on surface reflectivity has also been studied. It was found that laser induced surface microstructures on copper can decrease surface reflectivity by almost 90%. A comparative study of the effects of surface roughness and chemistry on the optical absorption of copper is given, finding that these surfaces are competitive with contemporary coatings.
165

A NUMERICAL STUDY FOR AERODYNAMIC PERFORMANCES OF NREL OFFSHORE 5-MW WIND TURBINE

Qiqing Zhang (11205621) 04 August 2021 (has links)
Wind energy is recognized as a sustainable source of energy that is both reliable and capable of dramatically reducing pollution to the environment and dependency on non-renewable fuels, leading to research on wind turbines. Nowadays, the demand for electricity increases. Considering that the greater the distance from shore, the greater the wind, more electricity will be generated along the coast. It is necessary and beneficial to study large scale offshore wind turbines. The National Renewable Energy Lab (NREL) 5-MW offshore wind turbine is simulated using a three-dimensional computational fluid dynamics (CFD) model in this article. A realizable k-ε viscous model is used to simulate turbulence flow. The work is validated by comparing the torque with published simulated data, and satisfied consistency is observed. Further simulation and comprehensive analysis demonstrate the flow features and aerodynamic performances of 5-MW offshore wind turbine under various wind and rotor speeds. The velocity profiles, total pressure distribution, pressure coefficient, rotor thrust, torque and aerodynamic properties are obtained in detail.
166

Bezdrátový přenos dat ze senzorů / Wireless transfer of the sensor data

Kičina, Andrej January 2008 (has links)
Thesys is focused on wireless transfer of the sensor data. It describes different wireless standards for potential use and realization of interface between sensor's data and their transfer. Crux of the matter is in detailed description of whole system with created utility programs. In the end it is summarized acquiered features of the realization.
167

The influence of a green building concept on the value of a building

Owoha, Faith January 2019 (has links)
Thesis (Master of Construction (Construction Management))--Cape Peninsula University of Technology, 2019 / This study examines the influence of a green building concept on the value of a building. Comprehensive literature was carefully reviewed to provide an overview on the concept of green building and its influence on the value of a building, subject to its overall benefits in South Africa. Several studies have been conducted giving guidelines for the determination of the best capitalisation rates needed for valuing green building properties. However, the information is still inadequate in providing evidence of the relationship between green building features and its influence on the value of a building, leaving most buildings with green features undervalued. This is a peculiar concern this research seeks to bring to notice and with its limited scope proffer possible recommendations and conclusions. A quantitative approach was adopted, facilitating the collection of data through the use of a questionnaire survey that involved randomly selected construction professionals in the Western Cape Province of South Africa. The motive behind the adoption of the quantitative method is to facilitate a reliable manner of satisfying the established aim and objectives for determining current practices in valuing green buildings. The above description paved the way for the use of theoretical, statistical and mathematical techniques for computation and interpretation of data to support objective reasoning and measures. Data was analysed with the application of descriptive and inferential statistical analysis tools, wherein the mean values and one-way analysis of variance were carefully determined. The findings demonstrate that the benefits of green building are critical for enhancing a building’s value. The benefits are divided into tangible and intangible benefits to classify impact on a building value. The classification of the impact cut across reduction of the consumption of energy and water, lowering operating cost and developing flexible design options. Some of the significant features of the green building include water metering, a photovoltaic solar panel system, electrical sub-metering, high performance building façade and skylight and borehole water. Further findings indicate that kitchen and water-closet (WC) water efficient fittings is ranked highest with a mean value (MV) of 3.91, followed by megawatt photovoltaic solar plant with an MV of 3.79, and water metering for monitoring and leak detection with an MV of 3.74. In light of the MVs, it is evident that these features significantly influence the value of a green building. Subsequently, the features are classified as: eco-friendly materials and energy conservation feature; water saving and renewable energy feature; safety feature; natural day light and control feature; sun shade and light feature; water management and flooring feature, and special utility feature. Information as gathered in the study demonstrate that the current practices engaged in valuing green building projects do not specifically differ among construction participants, although the perceptions of construction professionals regarding the most significant green building features that enhance the value of a building is on the average. Modalities towards promoting the concept and value of green building require resolute actions that should be implemented by the Green Building Council of South Africa. This concerns the creation of new growth strategies to escalate the awareness and implementation of a green building concept. Based on the benefits and significant features of green building, as determined through respondent affirmatives, this study broadens the view of construction professionals on the influence of a green building concept on the value of a building in South Africa.
168

The invasive Himalayan balsam : Current status in Umeå, Northern Sweden / Den invasiva jättebalsaminen : Nuvarande status i Umeå, norra Sverige

Snider, Bailey January 2022 (has links)
Impatiens glandulifera is an invasive species throughout Europe. It was introduced to the wild in 1918 by escape from private gardens as well as the transport of garden soil and waste. Impatiens glandulifera prefers moist soils with moderate shade and commonly grows in riparian environments. In the Umeå municipality in northern Sweden, where this study is focused, the number of Himalayan balsam observations has dramatically increased over the last few years. This study aimed to determine habitat and anthropogenic land-use factors that may have contributed to the spread of Himalayan balsam in the Umeå municipality. This was done by using data on recorded observations of the species in a database called Artportalen. In order to determine how abundant and in which habitats Himalayan balsam occurs in the Umeå municipality, data on recorded observations in Artportalen from the Umeå municipality region for the period 01-01-2021 to 31-12-2021 was used along with maps from Google Earth Pro and Google maps. It was found that Himalayan balsam is now common in the region and does not show a definitive preference for riparian habitats or for forest or open areas in the Umeå municipality. Human activities seemed to be the main contributor to the spread of Himalayan balsam in the Umeå municipality.
169

Geomorphic Features and History of the Lower Part of Logan Canyon, Utah

Williams, Edmund J. 01 May 1964 (has links)
Logan Canyon is located east of Logan, Utah, in the Bear River Range. The lower part of Logan Canyon is considered that section of the canyon from its mouth upstream to Tony Grove Canyon, a distance of 22 miles, Figure 1 Some tributary canyons of the lower part of Logan Canyon have been included in this investigation because of their relationship to Logan Canyon. Grassy Flat Canyon, a south tributary of Logan Canyon 4.4 miles from Logan, exhibits several geomorphic features related to the geology of Logan Canyon. Because of its extensive use and close association with Logan Canyon, Tony Grove Canyon is also included. Tony Grove Canyon extends from Logan Canyon northwestward to the crest of the Bear River Range, a distance of about six miles. More than 20,000 feet of Paleozoic rocks ranging in age from Cambrian to Pennsylvanian are exposed in Logan Canyon . Cenozoic deposits are widespread in and near the canyon. The crest of the Bear River Range near Naomi Peak and Tony Grove Canyon was the center of glacial activity during the Pleistocene. During the glaciations of Tony Grove Canyon, Lake Bonneville extended into Logan Canyon and influenced the geomorphic development near the mouth of the canyon. Logan Canyon is vital to the economy of Cache Valley. The canyon is a large part of the Logan River watershed. Logan River passes through three hydroelectric plants in Logan Canyon and supplies culinary and irrigation water for the valley below. Animals and plants of a wide variety are abundant, providing fishing , hunting, and a harvest of forest products. U.S. highway 89 traverses the canyon and carries a large volume of traffic to points within the canyon, as well as to other areas. Logan Canyon is entirely within the Cache National Forest. Improved campsites and recreational facilities, which were used by almost 1.5 million visitors during 1963; according to the U. S. Forest Service, are located throughout the Canyon. Increased recreational and travel use of the canyon has resulted in a demand for more geologic work in this area .
170

Feature Selection and Analysis for Standard Machine Learning Classification of Audio Beehive Samples

Gupta, Chelsi 01 August 2019 (has links)
The beekeepers need to inspect their hives regularly in order to protect them from various stressors. Manual inspection of hives require a lot of time and effort. Hence, many researchers have started using electronic beehive monitoring (EBM) systems to collect critical information from beehives, so as to alert the beekeepers of possible threats to the hive. EBM collects information by applying multiple sensors into the hive. The sensors collect information in the form of video, audio or temperature data from the hives. This thesis involves the automatic classification of audio samples from a beehive into bee buzzing, cricket chirping and ambient noise, using machine learning models. The classification of samples in these three categories will help the beekeepers to determine the health of beehives by analyzing the sound patterns in a typical audio sample from beehive. Abnormalities in the classification pattern over a period of time can notify the beekeepers about potential risk to the hives such as attack by foreign bodies (Varroa mites or wing virus), climate changes and other stressors.

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