• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 229
  • 61
  • 13
  • 12
  • 8
  • 5
  • 5
  • 5
  • 5
  • 5
  • 3
  • 2
  • 2
  • 2
  • 2
  • Tagged with
  • 613
  • 103
  • 96
  • 70
  • 68
  • 67
  • 66
  • 46
  • 45
  • 37
  • 35
  • 35
  • 35
  • 34
  • 33
  • 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.
221

On the Subject of Retroactive Characterisation in Games

Cimino, Santino, Persson Lundh, Linus January 2020 (has links)
This paper will create, define & develop the concept of retroactive characterisation as a narrative device for games. In doing so, it will investigate a method of conveying character and narrative to a player after a given event has already taken place, hence, retroactively. The paper will present data collected through surveys and interviews held in conjunction with test sessions. The paper presents and discusses this data through compiled diagrams and interview transcripts, in order to fulfill its purpose of determining the validity of retroactive characterisation as a narrative device in games.
222

Investigation of acoustic source characterisation and installation effects for small axial fans

Berglund, Per-Olof January 2003 (has links)
Fans are often used in equipment such as home appliances andelectronic equipment where the margin of profit is small butcustomers demands on a low noise level are high. Therefore,methods for predicting the noise emitted by an applicationincluding one or several fans are desirable in order toimprove, accelerate and reduce the cost of low-noise design.The Noise Shaping Technology (NST) has been developed withinthe EC-project NABUCCO in order to fulfil the aboverequirements on a prediction method. According to NST, thenoise source (not necessary a fan) is described by one orseveral noise descriptors, CSSs, and the correspondingtransmission paths through the structure described by one orseveral transfer functions, ACFs. In this thesis, theapplicability of NST is evaluated on a cabinet for electronicequipment where small axial cooling fans constitute the primarysources of the airborne sound. As an axial fan is a complex source of sound,simplifications are necessary when modelling its acousticproperties. Therefore, the sound radiation of an axial fan infree space was examined by expanding the generated soundpressure field into spherical harmonics. The conclusion on asource model for the cabinet example, where the fans are moreor less In-duct mounted, is a modified single axial dipole. Themodel is expected to be valid in the entire frequency range ofinterest except in the mid-frequency range where the modaldensity is low. In order to improve the source model in thisfrequency range, a future model based on a rotating dipole isproposed. The sound power of a small axial fan is measured in an ISO10302 test-rig. In order to take account of flow conditions,acoustically transparent ducts have been developed. These shallbe attached to the test-rig when measuring the sound power ofthe fan. A simple but practical method of how to correct thesound power for the baffling effect of the test-rig has alsobeen developed. Finally, the sound power can be converted intodipole force, which is the airborne CSS corresponding to thesingle axial dipole model. The corresponding airborne transfer function (ACF), i.e.,from dipole force at the source point to sound pressure at thereceiver point, is measured reciprocally by taking use ofLyamshevs reciprocity relation. From multiplication of the CSS and the ACF, the soundpressure can be predicted. The prediction shows quite goodagreement with the measured values. <b>Keywords:</b>axial fan, airborne sound, sourcecharacterisation, transmission path analysis, In-duct,spherical harmonics, rotating dipole, installation effects, ISO10302, flow conditions, baffling effect, acousticallytransparent ducts, Lyamshevs reciprocity relation, reciprocity,CSS, ACF, GSM, NST. / NR 20140805
223

Performance of a Micro-CT System : Characterisation of Hamamatsu X-ray source L10951-04 and flat panel C7942CA-22 / Prestanda hos ett Micro-CT System : Karaktärisering av Hamamatsu röntgenkälla L10951-04 och plattpanel C7942CA-22

Baumann, Michael January 2014 (has links)
This master thesis evaluated the performance of a micro-CT system consisting of Hamamatsu microfocus X-ray source L10951-04 and CMOS flat panel C7942CA-22. The X-ray source and flat panel have been characterised in terms of dark current, image noise and beam profile. Additionally, the micro-CT system’s spatial resolution, detector lag and detector X-ray response have been measured. Guidance for full image correction and methods for characterisation and performance test of the X-ray source and detector is presented. A spatial resolution of 7 lp/mm at 10 % MTF was measured. A detector lag of 0.3 % was observed after ten minutes of radiation exposure. The performance of the micro-CT system was found to be sufficient for high resolution X-ray imaging. However, the detector lag effect is strong enough to reduce image quality during subsequent image acquisition and must either be avoided or corrected for.
224

Geochemical and mineralogical laboratory methods in waste rock drainage quality prediction

Karlsson, Teemu January 2019 (has links)
Harmful substances containing acid or neutral rock drainages (ARD and NRD) are a major challenge related to the management of extractive industry wastes. This issue is particularly related to deposits containing sulphide minerals, which are prone to oxidization under the influence of atmospheric oxygen and water. The drainage quality depends mainly on the mineralogical and chemical composition of the extractive wastes, and especially on the ratio of acid-producing and neutralizing minerals, combined with reactions catalysed by microbes. Since harmful drainages play a major role in the generation of environmental issues for extractive industry, the accurate prediction of the drainage quality is of utmost importance. To design appropriate extractive waste facilities and drainage management, the characterisation of extractive wastes and assessment of the behaviour of the waste material is essential already before the actual mining activities start. Several methods have been developed to characterize extractive waste materials and to predict their short and long term behaviour, including e.g. geochemical laboratory tests, static tests and longer term kinetic tests, and geochemical modelling. The characterisation methods for assessing the ARD risk can be divided into static and kinetic tests. Static tests are short term laboratory analyses, usually used for preliminary investigation and screening. Kinetic tests are longer term tests, revealing information on the time scale of drainage events. Commonly used static tests for ARD prediction include acid–base accounting (ABA) tests and the net acid generation (NAG) test. Since acid and neutralisation potential largely depend on the ratio and quality of acid-producing and neutralizing minerals, mineralogical calculations could also be used for ARD prediction. The mobility of potentially harmful substances from extractive waste can be preliminary assessed using different geochemical laboratory tests, including selective extraction and leaching methods. The most commonly used selective extraction method in Finland is the aqua regia (AR) extraction. In addition to some silicates and secondary precipitate minerals, it is intended to dissolve elements bound especially to sulphide phases. A less commonly used method for element mobility prediction is the analysis of the single addition NAG test leachate. In this study, several Finnish waste rock sites were investigated and the performances of different preliminary drainage quality test methods evaluated and compared. The assessed acid production potential methods included the ABA test as presented in the standard EN 15875, the single addition NAG test as presented in the AMIRA guidebook, and a SEM mineralogy-based calculation. The assessed methods for element mobility prediction included the single addition NAG test leachate analysis and the AR extraction. According to the results, pyrrhotite seems to be the main mineral contributing to acid production, and the silicate minerals the main contributors to the neutralisation potential at the most Finnish waste rock sites. Since silicate minerals appear to have a significant role in ARD prevention, the behaviour of these minerals in mining environment should be more thoroughly investigated. In the investigated Finnish waste rocks, Co, Cr, Cu and Ni often occurred as elevated concentrations, and the most widely abundant harmful elements in the waste rock drainages were Co, Cu, Ni and Zn. The results suggest that an acid production prediction based on SEM mineralogical calculation is at least as accurate as the commonly used static laboratory methods. The AR extraction indicates well which elements might occur as elevated concentrations in the drainage. Also the NAG test leachate analysis performed well in element mobility assessment, but only when the NAG test leachate was sufficiently acidic, the leachate pH being below of 3-6, depending on the element of interest.
225

Determination of phenotypic characteristics, production systems, productivity, and contribution of local chickens to households in North-Central Namibia

Eiki, Ndahambelela 14 November 2016 (has links)
The phenotypic characteristics, level of production, management system and contribution of the local chickens to household studied in the north central Namibia. The study involved both qualitative and quantitative methods to gather the data. The questionnaire was used for survey while phenotypic characteristics and egg production forms were used to collect the actual data. The findings revealed that farmers in the study area regarded chicken production as their primary source of domestic animal protein, with the domestic fowl being the most widely kept poultry species. Other uses are participation in socio-cultural ceremonies, selling for money and gifts. The average number of eggs per clutch ranged from 10 to 15. The hatchability ranged between 50% and 60%). Phenotypic characteristics measures revealed the absence of pure white plumage colour that can be associated with the introduction of White Leghorn to the flock. Generally, normal feather cover was the main feather morphology of local chicken populations in north central Namibia. However, features like crested heads, naked necked, frizzling, and feathered shanks occurred sporadically among local chickens in the study area. Fifty-seven percentages of chickens in the surveyed region had single comb, while 29.6% and 13.8% had rose and pea combs respectively. The most frequent shank colour was black followed by yellow, whitish, orange, and reddish shank. The wing span had positive correlation with body weight and chest circumference at (r = 0.994). Other researchers discover the strong correlation of chest circumference with length shank at (r = 0.827). The current study attained the mean body weight of 1.7 to 2.1 kg of both sexes combined which falls within the range of 1.6 to 2.18 kg reported by (Alabi et al. 2012). In conclusion, the current study revealed large variation of phenotypical characteristics with poor correlation to their productivity due to lack of record keeping although production forms were made available to the farmers. The part of productivity according to their identified phenotypic characteristics is not accepted nor rejected due to poor records, but recommended for further study with training on record keeping by farmers / College of Agriculture and Environmental Sciences / M. Sc. (Agriculture)
226

On the Effect of Thin Film Growth Mechanisms on the Specular Reflectance of Aluminium Thin Films Deposited via Filtered Cathodic Vacuum Arc

Rincón-Llorente, G., Heras, I., Guillén Rodríguez, E., Schumann, E., Krause, M., Escobar-Galindo, R. 07 May 2019 (has links)
The optimisation of the specular reflectance of solar collectors is a key parameter to increase the global yield of concentrated solar power (CSP) plants. In this work, the influence of filtered cathodic vacuum arc deposition parameters, particularly working pressure and deposition time, on the specular and diffuse reflectance of aluminium thin films, was studied. Changes in specular reflectance, measured by ultraviolet–visible and near-infrared spectroscopy (UV-vis-NIR) spectrophotometry, were directly correlated with thin film elemental concentration depth profiles, obtained by Rutherford backscattering spectrometry (RBS), and surface and cross-sectional morphologies as measured by scanning electron microscopy (SEM) and profilometry. Finally, atomic force microscopy (AFM) provided information on the roughness and growth mechanism of the films. The two contributions to the total reflectance of the films, namely diffuse and specular reflectance, were found to be deeply influenced by deposition conditions. It was proven that working pressure and deposition time directly determine the predominant factor. Specular reflectance varied from 12 to 99.8% of the total reflectance for films grown at the same working pressure of 0.1 Pa and with different deposition times. This transformation could not be attributed to an oxidation of the films as stated by RBS, but was correlated with a progressive modification of the roughness, surface, and bulk morphology of the samples over the deposition time. Hence, the evolution in the final optical properties of the films is driven by different growth mechanisms and the resulting microstructures. In addition to the originally addressed CSP applications the potential of the developed aluminium films for other application rather than CSP, such as, for example, reference material for spectroscopic diffuse reflectance measurements, is also discussed.
227

Character voice in subtitles: a case study of the Japanese subtitles of The Witcher

Rusanen, Sirius January 2021 (has links)
In storytelling, one of the most important functions of dialogue is to create characterisation. Character voice is each character's unique style of speaking, which can impart explicit or implicit information about characters, such as their personality, age, or gender. Japanese language texts are known to use gendered language and role language (yakuwarigo) as a way of creating characterisation and character voice.This case study examines the English dialogue and the Japanese subtitles of four characters (Tissaia, Yennefer, Geralt, and Jaskier) from the series The Witcher. The aim was to categorize the strategies used to recreate the original character voice, to mark the differences in the character voices, and to examine their possible impact on the overall characterisations. The study concludes that the main strategy in creating character voice was gendered language and role language. Overall, the English and Japanese character voices were roughly equivalent with each other, and the used gendered language was supported by the characters’ personalities or appearance. The character Jaskier had the most differences between his English and Japanese dialogue, most likely due to the difficulties in recreating his brand of humorous tone in subtitle form.
228

The portrayal of racial characterisation in South African soap operas : the case of Skeem Saam

Mathobela, Ramasela Semang Lydia January 2021 (has links)
Thesis (M.A. (Media Studies)) -- University of Limpopo, 2021 / The emergence of democracy in South Africa brought a fallacious rainbow nation to permit all citizens to benefit from equal opportunities regardless of colour. The national broadcaster, SABC as a tool of transformation to promote multiracialism was meant to depict balanced representations of all races through its programmes such as soap operas. This study’s aim was to examine the depiction of racial characterisation in Skeem Saam which is broadcast by the SABC. The study employed a qualitative approach which allowed the use of descriptive analysis. Purposive sampling was used to determine the soap opera as the most appropriate to examine racial characterisation. The data was collected through qualitative content analysis which enabled the researcher to peruse Skeem Saam’s episodes which address the study’s objectives. Thematic content analysis was used to analyse the data which enabled the analysis of ten characters and the contexts these characters are portrayed in. The study found that there are negative racial misconceptions and stereotypes attached to Black character roles through occupational roles, personality traits, social and economic status as compared to White character roles. Therefore, that there is misrepresentation of Blacks through roles played by Black characters. The study recommends a need for transformative policy amendments which will bind soap opera producers to include realistic and balanced representations of race and gender. Narrative formations should also feature realistic developments in society rather fictional storylines that run at the expense of daunting Blacks growth in South Africa.
229

Examining a comparative depiction of crime in Smith and Nesbo's selected novels : an afro-western perspective

Malatji, Permission Agosi January 2019 (has links)
Thesis (M. A.(English Studies)) --University of Limpopo, 2019 / This study explores a literary comparative examination of crime between Africa and Scandinavia, with special attention to Botswana and Norway. Smith’s and Nesbo’s selected novels are used as primary texts for analysis. The novels are, therefore, set in two different areas. These writers depict crime from the African and European perspectives. Chapter One deals with a brief introduction, and the aim and objectives of the study. It also expands on the theoretical background and provides definitions of terms that are used in this paper. Chapter Two presents views from various scholars on crime. This study is based on an Afro-Western approach of literary analysis. In other words, there are thoughts by both African and Western writers which assist in determining possible and noticeable similarities and differences, on the issue of crime. Chapter Three analyses crime from an African perspective while Chapter Four discusses crime from a Western point of view. Each of these chapters reflects on crime through character portrayal and depiction within its context. Chapter Five is a comparative analysis of both novels. The chapter identifies possible similarities and differences, mainly of the depiction of crime in different settings – Africa and Scandinavia, committed by blacks and whites. However, the structural and linguistic approaches of both the novels are also reviewed, assisting in discovering the life, in comparison, of the authors. The last chapter (Chapter Six), is a conclusion of the study and future suggestions. Basically, the study argues that blacks only should not be portrayed as perpetrators, but that whites too can be culprits. Again, there should be an equal of measurement on the weight and honour of the two races. Lastly, the moral is that without considering skin colour, financial and social backgrounds, justice must be served equally. Hence, whoever is caught in any form of wrongdoing, they must be given the appropriate punishment – regardless of race, colour, religious creed, gender, financial and social background. Key Words: Crime, Afro-Western, Marxism, suspense, detective, identity, puzzle, fix, accumulation, class, characterisation and setting
230

NUMERICAL MODELING OF FLUID FLOW AND ARGON INJECTION IN PRIMARY COOLING OF CONTINUOUS CASTING PROCESS

Mingqian Wang (16745124) 04 August 2023 (has links)
<p>Continuous casting is a vital process in the production of semi-finished steel, converting molten metal into solid form. Primary cooling, a critical stage of this process, uses water to cool the solidifying shell as it descends through the mold. The quality of the final cast product is significantly influenced by the fluid flow characteristics during this phase. Given the inherent complexities and costs associated with experimental studies in this area, numerical modeling has emerged as a crucial tool for understanding, predicting, and optimizing fluid flow dynamics within the mold. This research focuses on the implications of argon injection within the mold during the primary cooling stage of the continuous casting process.</p><p>In this thesis, a comprehensive computational investigation of the transportation, entrapment, and fluid dynamic effects of argon injection is presented. Through an exploration of bubble sizes, SEN submergence depths, and slide gate openings, the study reveals how these parameters can significantly influence the casting process.</p><p>The research finds that argon bubble size plays a critical role in determining bubble trajectories and residence times, with smaller bubbles showing a longer residence time and increased boundary interaction due to the dominance of drag forces. The submergence depth of the submerged entry nozzle (SEN) also influences these factors, with deeper submergence resulting in longer bubble trajectories and greater residence times. The study highlights how bubble diameter impacts their entrapment probability, with bubbles ranging from 0.3mm to 0.6mm being most prone to entrapment.</p><p>The effects of argon injection on fluid flow within the SEN demonstrate an enhancement of turbulence, thus promoting a uniform outflow. However, excessively high argon flow rates risk a critical reduction in meniscus velocity, which could lead to overcooling. The research further elucidates the influence of argon on X-velocity near the mold's narrow faces, indicating a potential method for controlling dendritic growth and enhancing the final product quality.</p><p>This work underlines the complex and multifaceted impacts of argon injection on the continuous casting process. It suggests that through careful manipulation of argon bubble size, SEN submergence depth, and slide gate opening, it is possible to optimize the transportation and entrapment of argon bubbles, manage fluid flow dynamics, and ultimately, improve the quality of the cast product.</p>

Page generated in 0.1151 seconds