Yes / There is increasing concern with protecting quiet and tranquil areas from intrusive noise. Noise reduction at source and barriers to transmission are mitigation measures often considered. An alternative is to attempt to mask or distract attention away from the noise source. The masking or distracting sound source should be pleasant so that it does not add to any irritation caused by the noise source alone. The laboratory measurements described in this paper consisted of capturing under controlled conditions the third octave band spectra of water falling onto water, gravel, bricks and small boulders and various combinations. These spectra were then matched with typical traffic noise spectra to assess the degree of masking that could be expected for each option. Recordings were also taken during each measurement and these were used later to enable the subjective assessment of the tranquility of the sounds. It was found that there were differences between water sounds both in terms of masking and their subjective impact on tranquility.

The turbulent flow through a marine propulsor was experimentally modeled using a large cascade configuration with six 33 cm chord flat plates spanning the entire height of the test section in the Virginia Tech Stability Wind Tunnel. Three-component hot-wire velocity measurements were obtained ahead, throughout and behind both an unstaggered and a 35º staggered cascade configuration with blade spacing and onset turbulence integral scales on the order of the chord. This provided a much needed data-set of much larger Taylor Reynolds number than previous related studies and allowed a thorough investigation of the blade-blocking effects of the cascade on the incident turbulent field. In order to generate the large scale turbulence needed for this study, a mechanically rotating "active" grid design was adopted and placed in the contraction of the wind tunnel at a streamwise location sufficient to cancel out the relatively large inherent low frequency anisotropy associated with this type of grid. The resulting turbulent flow is one of the largest Reynolds number (Reλ  1000) homogeneous near-isotropic turbulent flows ever created in a wind tunnel, and provided the opportunity to investigate Reynolds number effects on turbulence parameters, especially relating to inertial range dynamics. Key findings include 1) that the extent of local isotropy is solely determined by the turbulence generator and the size of the wind-tunnel that houses it; and 2) that the turbulence generator operating conditions affect the shape of the equilibrium range at fixed Taylor Reynolds number. The latter finding suggests that grid turbulence is not necessarily self-similar at a given Reynolds number independent of how it was generated. The experimental blade-blocking data was compared to linear cascade theory and showed good qualitative agreement, especially for wavenumbers above the region of influence of the wind tunnel and turbulence generator effects. As predicted, the turbulence is permanently modified by the presence of the cascade after which it remains invariant for a significant downstream distance outside the thin viscous regions. The obtained results support the claim that Rapid Distortion Theory (RDT) is capable of providing reasonable estimates of the flow behind the cascade even though the experimental conditions lie far outside the predicted region of validity. / Ph. D.

This dissertation presents measurements of the far-field noise associated with the interaction of grid-generated turbulence with a series of airfoils of various chord lengths, thicknesses, and camber. The radiated noise was measured for a number of angles of attack for each airfoil to determine the effects of angle of attack on the leading edge noise. Measurements are compared with numerous theories to determine the mechanism driving the production of leading edge noise. Calculations were also made using a boundary element method to determine the effects of airfoil shape on the unsteady loading spectrum on the different airfoils to attempt to explain the far-field noise. Measurements of the unsteady surface pressure on a single airfoil were made for a number of angles of attack to determine the effects of wind tunnel interference corrections on the unsteady surface pressure. These measurements were compared with those of Mish (2003) to determine the effects of the interference correction. An attempt was also made to correlate the unsteady loading on the airfoil with the far-field noise. The airfoils studied were a 0.203-m chord NACA 0012, a 0.61-m chord NACA 0015, a 0.914-m chord NACA 0012, a 0.914-m chord DU96, and a 0.914-m chord S831. All airfoils spanned the entire 1.83-m height of the test section. Measurements were made using the Virginia Tech Stability Wind Tunnel in its acoustic configuration with an anechoic test section with side walls made of stretched Kevlar fabric to reduce aerodynamic interference. Measurements were made in grid-generated turbulence with an integral length scale of 8.2-cm and a turbulence intensity of 3.9%. Far-field noise measurements were made at Mach numbers of 0.087 and 0.117 with various configurations of up to 4 Bruel and Kjaer microphones mounted at an observer angle of 90° measured from the wind tunnel axis. Unsteady surface pressure measurements were made on the NACA 0015 airfoil immersed in the same grid generated turbulence used in the far-field noise study. An array of microphones mounted subsurface along the airfoil chord and a spanwise row was used to measure the unsteady surface pressure. These measurements were made at angles of attack from 0 through 16° in 2° increments. Far-field noise measurements of the leading edge noise show a consistent angle of attack effect. The radiated noise increases as the angle of attack is increased over the frequency range. These effects are small for large integral scale to airfoil chord ratios. The larger airfoils have been shown to generate significantly less leading edge noise at high frequencies, but this effect does not appear to be solely dependent upon the leading edge radius. The leading edge noise can be predicted with accuracy using the method of Glegg et al. (2008). Unsteady surface pressure measurements have been shown to be largely independent of the wind tunnel interference correction as shown by comparison with Mish (2008). The same low frequency reduction described by Mish was seen for an interference correction that was nearly 30% larger. The unsteady sectional lift spectra have been shown to be related to the far-field noise spectra by a factor close to the dipole efficiency factor; however, no correlation could be found between the instantaneous unsteady surface pressure and the radiated noise. The spanwise averaged unsteady pressure difference spectra have been shown to be related to the far-field noise spectra by the dipole efficiency factor. / Ph. D.

Artificial Intelligence (AI) has become increasingly prevalent in society with the rise oftools like Stable Diffusion. This evolution has shown an increase in the use of AI picturesin different fraud cases. To combat this, some researchers are in the process of trainingneural networks to detect AI-generated images. However, these tools are not perfect andare not always commercially available. Thus, to increase resilience against this kind offraud, this study lists practical methods for spotting AI-generated images and measurespeople’s perceived abilities against their actual abilities to determine whether the pictureis generated or not. These results are based on a survey designed to determine standard techniques people use to spot AI images and discern their self-rated ability to detectthem. To conclude, the participants rated their ability to detect generated images lowerthan their actual ability turned out to be. The most effective techniques are looking forincorrect shadows, blurry skin or textures, lack of texture/fine details, incorrect amount ofhands/fingers, abnormal background details, lack of imperfections, poor picture qualityand reflections.

近年来，中国内地市场化报纸纷纷开设"报网互动栏目"来常规性吸纳和利用网络用生成内容。本文试图对这一现象作出描述、分析和解释。本研究从新闻常规和新闻内容两个面向，对作为中国"报网互动栏目"范例的《S报》"网"版进行了考察。考察围绕以下问题展开："报网互动"栏目的新闻常规是什么？它与一般新闻常规有何异同？这些新闻常规是如何形成的，又发挥了怎样的作用？是否帮助"报网互动栏目"突破中国媒体在践行传媒公共性上的局限？为什么会出现这样的情况？以往对用生成内容、新闻常规以及传媒公共性三者关系的研究都主要产生于自由主义传统的社会。本研究将为此提供一个新的参照，其背景是像中国内地这样的非自由主义传统的社会。 / 本研究通过对《S报》"网"版的考察发现，"网"版在吸纳用生成内容时因应出一定的以公共性为导向的新常规，这些常规主要存在于新闻生产的发现、选择、报道以及撤稿等环节。在这些常规的作用下，"报网互动栏目"重视吸纳与公共利益相关、尤其是与监督公权力相关的用生成内容，并在报道中彰显出鲜明的民间立场。但是，《S报》同时保留了既定的对传媒公共性具有破坏作用的新闻常规。这些新闻常规限制了"报网互动栏目"对传媒公共性追求，使其难以突破过往中国媒体在践行传媒公共性上的局限性。 / 中国内地市场化报纸"报网互动栏目"所展示出的局限的公共性是国家、市场、新闻专业主义和互联网技术等多重因素共同作用的结果。其中，国家、市场、新闻专业主义均不同程度地发挥了促进和破坏传媒公共性的双面作用。因此，尽管互联网科技为传媒提供了提升自身公共性的可能性，但这种可能性在特定的权力结构中被消解。 / In recent years, market-driven newspapers in China have increasingly established the "Press-Internet Interaction Section [Baowang Hudong Lanmu]" to regularly incorporate user-generated content. This dissertation tries to describe, analyze, and explain this phenomenon. The study examines the news routine and news content of one exemplary section, "The Net Section" of S-News. The exploration focuses on the following questions: What is the news routine in this "Press-Internet Interaction Section"? Is it different from established newspaper routines? How is it formed? How does it work? Does the news routine promote the publicness of the news content? And why? So far most existing literature on this topic examines cases in societies with liberal traditions of news-making. This study provides a new point of reference in the contexts of societies outside the liberal traditions such as in China. / This study finds that S-News has established several new public-oriented routines to appropriate the user-generated content. Meanwhile, the newspaper also retains some established routines that threaten the publicness of media. These two types of news routines make the news content of "Press-Internet Interaction Section" only show limited publicness as other Chinese media. / The performance of "Press-Internet Interaction Section" is the result of a confluence of factors. The factors include the state, the market, the journalistic professionalism and the Internet. Except the Internet, all three other factors construct and destruct the publicness of media to varying degrees. As a result, the possibility provided by the Internet to increase the publicness of media has been minimal within established power structures. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / 張偉偉. / Thesis (Ph.D.) Chinese University of Hong Kong, 2014. / Includes bibliographical references (leaves 265-283). / Abstracts also in English. / Zhang Weiwei.

Thesis (M.Sc. (Mathematics)) -- University of Limpopo, 2021 / We study balanced filters and balanced z-filters considered by Carlson in [20] and [21] in topological spaces. We consider closed filters which are open-generated and open filters which are closed-generated. We show that a closed filter is open-generated precisely if it is a minimal balanced closed filter and that an open filter is closed-generated precisely when it is a minimal balanced open filter. For a completely regular topological space X, we study balanced z-filters and show that there is a one-to-one correspondence between the nonempty closed sets of βX and the balanced z-filter on X. By dualising closed filters we obtain ideals which then enables us to put some of the results in the context of frames. Dube in [28] has shown that a frame is normal if and only if its closed-generated filters are precisely the stably closed-generated ones. By dualisation we show that a frame is extremally disconnected if and only if its open-generated ideals are precisely the stably open-generated ones. We show that there is one-to-one correspondence between points of βL and the balanced ideals of Coz L. Furthermore we study nearness frames and show that the locally finite nearness frames strictly contain the Pervin nearness frames and the two coincide if the locally finite nearness frames are totally bounded. For perfect extension h : M → L of L, we show that a point p of M is a remote point if and only if Ip = {a ∈ L | h∗(a) ≤ p}. / University of Limpopo and DST - NRF Centre of Excellence in Mathematical and Statistical Sciences (CoE - MaSS)

Funding strategy has often been the determinant factor in the level of success for social entrepreneurships. The strategy could be a preference for internally generated revenue, externally generated revenue or a combination of the two. Interestingly, scarcity of resources has always been ‘a clog in the wheel’ of meaningful execution of projects irrespective of the funding model a social entrepreneur chooses. Through a review of existing literatures, this paper weighs the implications of choosing either externally generated revenue or internally generated revenue; specifically contextualizing the study to US. More so, it attempts to find out which of the two models would ensure optimum productivity, given that scarcity of resources would hamper the chances of effectively running the two models simultaneously. To arrive at a ‘plausible’ response, principles of resource valuation become vital in determining the costs and benefits associated with each model of funding. Consequently, the findings show that though both internally and externally generated revenue are sine qua non to an effective and efficient production of social values, internally generated revenue ensures better optimum production than externally generated revenue.

In dieser Bachelorarbeit wird eine Beispiel-E-Learning-Lektion zum Import von GPS Daten in die Kartenherstellungssoftware OCAD erstellt. Dabei liegt im theoretischen Teil der Hauptschwerpunkt auf nutzergenerierten Daten (Volunteered Geographic Infor-mation; kurz: VGI). Nach einer kurzen, allgemeinen Einführung wird auf die Bedeutung der Kartographie im Zusammenhang mit VGI eingegangen. Der zweite Teil beinhaltet Didaktik mit Schwerpunkt E-Learning. Dazu werden das Goal Based Scenario Modell und das Cognitive Apprenticeship Modell kurz vorgestellt und anschließend das Projekt GITTA mit der enthaltenen ECLASS-Struktur näher erklärt. Den immer wichtiger werdenden Content Management Systemen (CMS) widmet sich der dritte Theorieteil. Für die Realisierung der zu erstellenden Lektion wird das Open-Source CMS Joomla! ausführlicher erläutert. Die Implementierung beschreibt die Umsetzung der E-Leraning-Lektion mittels Joomla! und die Nutzung des ECLASS-Modells. Bevor auf die Vorgehensweise eingegangen wird, enthält der Implementierungsteil die Erstellung eines groben Gesamtkonzeptes für eine komplette E-Leraning-Anwendung zu OCAD mit entsprechenden Erläuterungen. Anschließend folgen eine Zusammenfassung und ein Ausblick über die Weiterführung der E-Learning-Anwendung.

Lerncontentmodelle beschreiben den modularen Aufbau von Lernmaterialien auf verschiedenen Komplexitätsebenen von Assets bis hin zu fertigen Kursmaterialien. In Autorenwerkzeugen wird diese Untergliederung oft unterstützt, bspw. durch Mediendatenbanken, modularisierte Inhaltsstrukturen oder pädagogische Metadaten zum unterstützten Lernszenario. User Generated Content in Social-Software-Anwendungen entsteht nicht auf diesem strukturierten Weg, sondern spontan und abhängig von den bereitgestellten Funktionen. Der Beitrag zeigt, dass sie sich aber weiterhin bezüglich ihrer Abhängigkeit vom Lernkontext klassifizieren lassen. Als Abstufungen ergeben sich Assets, Informations- und Lernobjekte, zielgruppenbasierte Zusammenstellungen und Kursunterlagen. Damit soll einerseits eine taxonomische Grundlage geschaffen werden, um User Generated Content als Lernmaterialien einzuordnen, es ist aber vornehmlich ein erster Schritt hin zur deren systematischer Re-Integration in institutionelle Lernmaterialien.

Syftet med denna studie är att undersöka fördröjningsskillnader inom användargränssnitt mellan native­utvecklade appar (utveckling till varje plattform) och appar av typen generated apps. Eftersom arbetet syftar till att bidra med information om prestanda ansågs en experimentell metod vara det bästa valet. Mätning av laddningstider gjordes med hjälp av en videokamera som filmade utförandet av experimenten vilket gjorde metoden simpel och liknar det som en användare kommer att uppleva. Avgränsning till plattformarna Android och iOS gjordes där Xamarin valdes som ramverk inom tekniker som skapar generated apps. Mätdata från experiment som undersökte laddningstider, experiment med användare som hanterade listors respons samt undersökning av CPU­ och minnesanvändning tyder på ett återkommande mönster. Xamarin Forms med XAML är den teknik som presterat sämst under experimenten som sedan följs av Xamarin Forms. Xamarin Android/iOS hade inte lika stora prestandaförluster jämfört med native­utvecklade delar. Generellt hanterar Xamarin Forms telefonens resurser sämre än vad Xamarin Android/iOS och native gör. Resultat från studien kan användas som beslutsstöd vid val av teknik. Studien bidrar även med data som kan användas vid vidare forskning inom området. / The purpose of this study is to examine differences in delay during calculation and presentation of interfaces executing on different techniques. Specifically between native developed apps and generated apps. Since the work aims to contribute with information regarding performance, an experimental method was considered to be the best choice. Measurements of loading times was made with a video camera that captured the execution of the experiments which made the method simple and captures what the users would have experienced. Demarcation to the platforms Android and iOS was made and Xamarin was chosen as the framework for creating generated apps. Data from experiment that examined loading times, experiment with users that dealt with the responsiveness of lists and the analysis of CPU and memory usage indicate a recurring pattern. Xamarin Forms with XAML is the technique that has performed worst during the experiments, followed by Xamarin Forms. Xamarin Android/iOS didn’t have as big performance loss. Xamarin Forms does not manage the phones resources as efficient as Xamarin Android/iOS and native developed apps does. The results from this study can be used as material for making decisions witin organisations when choosing technology for creating apps. The study also contribute with data that can be used by other researchers.