Faculty of Science School of Geography And Archaeology and Enviromental Studies 9905693x Nicola@crg.bpb.wits.ac.za / The Cape Town brown haze is a brown-coloured smog that is present over the Cape Town atmosphere during the winter months due to the accumulation of gaseous and particulate pollutants. The main aim of this research was to evaluate the impact of atmospheric pollutants to visibility impairment by the brown haze through visibility modelling of major pollution sources around the City of Cape Town. The screening model, VISCREEN, the Plume Visibility model, PLUVUE II and the CALPUFF Modelling System were employed to model the visual impact of emissions from the major sources. Two point sources, Caltex Oil Refinery and Consol Glass, and three area sources, Cape Town Central Business District (CBD), Cape Town International Airport and the townships of Khayelitsha and Mitchell’s Plain were identified as the major sources. An initial screening analysis indicated that emissions from the two industrial sources would be visible and would result in a yellow-brown discolouration of the atmosphere. Detailed modelling using PLUVUE II identified the area sources of Cape Town CBD and the townships to be the significant contributors to visibility impairment over Cape Town. Plume perceptibility is primarily dependant upon particulate emissions while NOx emissions influence the colouration of the atmosphere. CALPUFF was employed to assess the distribution of NOx, SO2 and PM10 concentrations over the area and the associated visibility impairment on a nonhaze (13 August 2003) and haze day (22 August 2003). Pollutant concentrations were considerably reduced on the non-haze day compared to the haze day. The Cape Town CBD was an important source of all the major pollutants with the townships contributing significantly to the aerosol loading over Cape Town. Pollutant concentrations are particularly elevated during the late evening and early morning periods, particularly between 7 am and 8 am. Visibility impairment is greatest on the haze day, particularly over the central Cape Town region and the townships. The greatest reduction in visibility is experienced between midnight and 9 am which corresponds with the periods of elevated atmospheric pollutant concentrations.

Lack of visibility of the assets in a product supply chain compromises attempts to optimise supply chain management. Increasing the visibility of these assets presents a relatively unexplored frontier in operations and supply where organisations can create competitive advantage through the opportunities asset visibility offer. This research aims at investigating the key capabilities of asset visibility specifically those associated with returnable transport assets that travel across supply chains carrying material and products e.g. cages, boxes, trays, trolleys and pallet bins. In addition, how these capabilities may influence supply chain visibility and firm performance in a way that might lead to sustainable competitive advantage is examined. To achieve these objectives, the research develops a two-stage model that is theoretically grounded in the extended resource-based view. Philosophically, the research adopts a critical realist approach using abductive logic. Methodologically, a sequential exploratory strategy for data collection is implemented. A qualitative, indepth site-based case study supported by field expert interviews was conducted as a pilot study. The pilot study findings refined the initial conceptual model derived from literature and informed the next stage of the research. The quantitative phase focused on refining the factors constituting asset visibility capabilities and then testing the relationship between these capabilities and supply chain visibility, performance and sustainable competitive advantage. Key findings are that asset visibility capabilities are shaped through three key capabilities: (1) an asset management capability formed by both core technological aspects related to tracking and tracing technology, and non-technological ones focusing on logistic-related capability; (2) a complementary technological capability comprising of IT infrastructure for supply chain integration; and (3) a complementary nontechnological capability represented through three sub-capabilities: (a) supply chain process integration; (b) focal firm-3PL relational orientation; and (c) internal firm integration. The research findings prove a positive relationship between asset visibility capabilities and supply chain visibility. In addition, a positive relationship between these capabilities and sustainable competitive advantage through the mediated effect of supply chain visibility and firm performance, is confirmed.

Narcissism refers to persistent feelings of grandiosity, a need for admiration, and a lack of empathy (American Psychiatric Association 2013). The literature has found narcissism to be associated with individuals making decisions for a firm that fulfill their egos rather than maximize firm value. The literature in psychology, however, suggests that when firms face financial distress, narcissism could be a desirable trait in an individual, enabling the CEO to take the necessary risks and make the necessary decisions for the firm to recover. I study the context under which a firm may benefit from a narcissistic CEO. In this study, I use two measures from prior literature (CEO photo prominence in the annual report and a CEO’s use of first-person personal pronouns) to form a combination measure to investigate whether firms in financial distress are more likely to appoint a CEO with more narcissistic traits. I find some evidence to support this hypothesis. I also examine whether the association between narcissism and future firm performance is affected by the economic conditions of a firm and the visibility of the firm. I find results consistent with firm financial distress increasing a narcissistic CEO’s effect on firm performance in low-visibility firms.

This thesis explores themes of visibility in the work of Jacques Rancière, Judith Butler and Adriana Cavarero. It argues that visibility is important for each author: for Rancière the making visible of particular existents; for Butler the making visible of violences; and for Cavarero the making visible of another’s uniqueness. However, these commitments to visibility reach a limit when confronted with those who exist in indifference to visibility, for example, the fugitive politics of the enslaved as detailed by Saidiya Hartman. In these instances there is a danger that a fugitive politics is overlooked if visibility is one’s primary frame of analysis. This thesis is interdisciplinary, bringing each author into conversation with the others but not attempting to synthesise their thought into a whole, nor to resolve the tensions in their work by privileging one author over the others. Instead, and following Rancière, it reads each author for their aesthetic contribution to making sense of the world with the aim of identifying the forms of existence that are opened up in their work, but also those that are closed down. The first chapter identifies themes of visibility in Rancière’s account of politics, arguing that there is an ambivalence in Rancière’s politics but that in either case politics is linked to the making visible of forms of existence that are otherwise rendered insensitive. The second and third chapters identify themes of visibility in Butler’s account of violence, arguing that Butler’s reflections on violence’s visibility are overlooked in her consideration of nonviolence. The fourth and fifth chapters identify themes of visibility in Cavarero’s work, arguing that her insistence on making another’s uniqueness visible is made urgent because of scenes of violence. The sixth chapter argues that Butler and Cavarero’s work should be understood as an insurrectionary humanism centred on the paraontology of vulnerability. The seventh chapter reads Rancière, Butler and Cavarero in relation to Hannah Arendt, arguing that it is Arendt’s proximity to each author that enables a politics of fugitivity to become tangible in their work. The eighth chapter reads Rancière, Butler and Cavarero against Saidiya Hartman’s account of the Middle Passage, plantation slavery and its legacies to demonstrate the limits of their commitment to visibility and to further manifest a sense of a fugitive politics indifferent to visibility.

This thesis presents a study on the subtitler's visibility management as manifested by their subtitling approaches. The special textuality and the recent digitization of subtitling practices make the subtitler's visibility management through subtitling an issue that is rather distinctive from the translator's visibility in general. Previous studies that directly investigate subtitler's visibility tend to focus on subtitler's relatively restricted and/or linear social interactions, while relevant discussion that examines their non-linear social interactions such as subtitling is very rare. Almost no study has provided either a conceptualization of subtitler's visibility or a systematic analytical framework specifically for analysing the subtitler's visibility management through subtitling. In the current study, the author examines the subtitler's visibility management through subtitling by comparing WHV industrial subtitlers' and YYeTs fansubbers' subtitling approaches to The Big Bang Theory. Based on Nornes's (2007) notions of corrupt and abusive subtitling and Ortabasi's critiques on the lack of multimodality in these notions, it has been hypothesized that the two groups of subtitlers' approaches differ in two dimensions and three aspects of issues. Accordingly, an analytical framework is constructed to systematically interrogate the two groups of subtitlers' visibility management as reflected by their subtitling approaches: 1) comparing their subtitling approaches to the verbal and nonverbal issues identified in the represented dimension; 2) comparing their subtitling approaches to the technical issues identified in the representing dimension; 3) comparing and discussing how their relatively different approaches in the two dimensions demonstrate their different visibility management. The findings suggest that the ways in which WHV industrial subtitlers and YYeTs fansubbers manage their visibility differently are multifaceted and bidimensional. First, the industrial subtitlers tend to adopt a relatively corrupt approach and the fansubbers tend to adopt a relatively abusive approach in the represented dimension, while the relative differences between their approaches are more drastic in the verbal aspect than in the nonverbal aspect. Second, the above-found relative differences between the two groups of subtitlers' approaches are even more explicitly consistent in the technical aspect of the representing dimension. Third, in both dimensions, the industrial subtitlers gain less visibility through the relatively corrupt approach and the fansubbers acquire more visibility through the relatively abusive approach. More profoundly, by adopting the relatively corrupt approach, the industrial subtitlers perform gatekeepers in the represented dimension and adherents in the representing dimension; by using the relatively abusive approach, the fansubbers present themselves as educators in the represented dimension and as innovators in the representing dimension. Beyond these findings, this thesis also makes broader theoretical and methodological contributions. It has demonstrated how a nonbinary and generative conceptualization of the subtitler's visibility from a sociological perspective, hitherto never provided by previous discussions, can lead to more fruitful investigations on the subtitler's visibility management. This combination of Nornes's (2007) notions of corrupt and abusive subtitling and Ortabasi's (2007) critiques on them offers us a set of analytical tools for thoroughly investigating how subtitlers manage their visibility differently through subtitling.

We describe a method called Visible Decomposition for computing collision-free paths in real time through a planar environment with a large number of obstacles. This method divides space into local visibility graphs, ensuring that all operations are local. The search time is kept low since the number of regions is proved to be small. We analyze the computational demands of the algorithm and the quality of the paths it produces. In addition, we show test results on a large simulation testbed.

Research on mental disability in the Sub-Sahara African context has recently stagnated, and is in need of a revival. The objectives of this study was to examine (i) the current situation of children and youth with mental disabilities in the Morogoro Region, Tanzania, and (ii) how to create more community awareness on rights of people with mental disabilities in the society, to put the discussion of mental disabilities back on the agenda. To fully grasp the cultural context, we have used interviews with local professionals working with children and youth with mental disabilities, in order to gain knowledge of efficient ways to create more community awareness. Over time there has been a change of attitudes due to improved knowledge, mainly through the increased visibility of people with mental disabilities in the society. However there is still a need to create awareness of the rights of people with mental disabilities, especially in rural areas. In order to influence the current situation for this group, we have concluded, within the frames of social constructionism, that networking through a bottom-up approach could be appropriate to share the burden.

Purpose: Previous studies have shown that some digital filters can enhance picture-image visibility for people with visual impairment. The ultimate purposes of this study are to determine the improvement of picture-image visibility for people with maculopathy using digital image enhancement, and to compare the enhancement effects of generic filters and custom-devised filters. The secondary interests are to investigate the effect of age and maculopathy on supra-threshold contrast matching and to investigate the spatial frequency characteristics of picture-images. Methods: In order to develop effective custom-devised filters, supra-threshold contrast matching and contrast thresholds for two age groups of subjects with normal vision (14 aged 20-50 years and 15 aged 51+ years) and three groups of people with maculopathy (13 with atrophic ARMD, 14 with exudative ARMD, and 8 with JMD) were measured. Amplitude spectrum at each spatial frequency and the slope of amplitude versus spatial frequency were measured to investigate the spatial frequency characteristics of single face and general scene images. To investigate the preference for filters, 7 generic filters and 4 custom-devised filters were applied to single faces and general scenes. The generic filters were high-pass/unsharp masking, contrast enhancement, Sobel edge enhancement, DoG convolution, DoG FFT, Peli’s adaptive enhancement, and a band-pass filter with equi-emphasis of spatial frequencies. The custom-devised filters were band-pass filters based on contrast sensitivity (CS) loss, contrast matching at 3.6% and 27.9%, and emphasis of the peak of the CS curve. Subjects with maculopathy were required to rate the visibility of each image with and without filtering. Nine subjects with maculopathy participated to assess the enhancement quantitatively during which the recognition of facial expression and details in general scenes was tested with and without filtering. Results: Contrast constancy was demonstrated in age-matched controls and people with maculopathy. Single faces were found to be of significantly lower average amplitude than the other groups of images. Eight filters were found to be effective in improving perceived visibility; contrast enhancement, Peli’s adaptive enhancement, DoG convolution, high-pass/unsharp masking, Sobel edge enhancement, band-pass based on 3.6% and 27.9% contrast matching and equi-emphasis band-pass filters. These filters specifically were found to be effective for one or more combinations of maculopathy type and image category. The most commonly preferred filters were the generic filters, contrast enhancement and Peli’s adaptive enhancement. The two highest rated filters for each subject significantly reduced the number of errors of facial expression and errors of recognition of detail within general scene images. Conclusions: The visual system adjusts to compensate for CS loss with aging and maculopathy. Single faces are unique in spatial frequency characteristics. Some generic and custom-devised filters are effective in enhancing image visibility. The custom-devised filters are not superior to the generic filters. Visibility enhancement can be assessed quantitatively.

Purpose: Previous studies have shown that some digital filters can enhance picture-image visibility for people with visual impairment. The ultimate purposes of this study are to determine the improvement of picture-image visibility for people with maculopathy using digital image enhancement, and to compare the enhancement effects of generic filters and custom-devised filters. The secondary interests are to investigate the effect of age and maculopathy on supra-threshold contrast matching and to investigate the spatial frequency characteristics of picture-images. Methods: In order to develop effective custom-devised filters, supra-threshold contrast matching and contrast thresholds for two age groups of subjects with normal vision (14 aged 20-50 years and 15 aged 51+ years) and three groups of people with maculopathy (13 with atrophic ARMD, 14 with exudative ARMD, and 8 with JMD) were measured. Amplitude spectrum at each spatial frequency and the slope of amplitude versus spatial frequency were measured to investigate the spatial frequency characteristics of single face and general scene images. To investigate the preference for filters, 7 generic filters and 4 custom-devised filters were applied to single faces and general scenes. The generic filters were high-pass/unsharp masking, contrast enhancement, Sobel edge enhancement, DoG convolution, DoG FFT, Peli’s adaptive enhancement, and a band-pass filter with equi-emphasis of spatial frequencies. The custom-devised filters were band-pass filters based on contrast sensitivity (CS) loss, contrast matching at 3.6% and 27.9%, and emphasis of the peak of the CS curve. Subjects with maculopathy were required to rate the visibility of each image with and without filtering. Nine subjects with maculopathy participated to assess the enhancement quantitatively during which the recognition of facial expression and details in general scenes was tested with and without filtering. Results: Contrast constancy was demonstrated in age-matched controls and people with maculopathy. Single faces were found to be of significantly lower average amplitude than the other groups of images. Eight filters were found to be effective in improving perceived visibility; contrast enhancement, Peli’s adaptive enhancement, DoG convolution, high-pass/unsharp masking, Sobel edge enhancement, band-pass based on 3.6% and 27.9% contrast matching and equi-emphasis band-pass filters. These filters specifically were found to be effective for one or more combinations of maculopathy type and image category. The most commonly preferred filters were the generic filters, contrast enhancement and Peli’s adaptive enhancement. The two highest rated filters for each subject significantly reduced the number of errors of facial expression and errors of recognition of detail within general scene images. Conclusions: The visual system adjusts to compensate for CS loss with aging and maculopathy. Single faces are unique in spatial frequency characteristics. Some generic and custom-devised filters are effective in enhancing image visibility. The custom-devised filters are not superior to the generic filters. Visibility enhancement can be assessed quantitatively.

The development of the global luxury market, nearly showing a decade growth of high degree, primarily refering the consumers of luxury market.It expanded not only high status but also general status and it¡¦s different from our past cognitive. Consumption is not a bad thing, but recently consumers change their shopping motives and want to show their status and obtain the identity of others by pursuiting the consumption patterns of higher classu, it will cause the disequilibrium between consumption and status. Therefore, this study explores the relationship between the socialization of status consumption and luxury attitude, and then extended to understand the impact of various media in the consumer socialization process, to identify the major cause of the disequilibrium. This object of the study expandes to the general consumers, it refers to widely understand the consumers actual cognition¡Bemotions and behavior whether he bought luxury goods or not. And exploring the relationship of luxury attitude and status consumption,in which you can understand the role of government in the consumer market and effect. After the questionnaire analysis, we found it is positive relationship between the luxury attitude and the status consumption,and it also has significant relationship between the attitude the consumer socialization process of media¡Gage¡Bthe school pattern in high school ¡B the cognition of government policy and luxury attitude. In conclusion, the luxury¡§cognition¡¨ and¡§emotion¡¨"are major causes to influence status consumption,it said the consumer to do the consupmtion behavior is depending the inherent performance.If consumers do not face their own wrong consumption mode, the overall social climate of the country will not upgrade.