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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.
21

Better infamous than unknown? : A study on the media effects of a scandal on corporate reputation and visibility

Johansson, Linnea January 2016 (has links)
In this paper I theorize about how a company’s corporate reputation and visibility can be affected by a scandal. Scandals are associated with negative outcomes such as bad reputation but this thesis investigates if there are some positive side-effects of a scandal in terms of increased visibility. The idea of it being better for companies to be infamous than unknown is studied using the empirical example of the payment service company Klarna AB, their scandal in April of 2014 is the focus of the thesis. The results show that the company’s visibility was affected in a positive way following the scandal since the number of articles about Klarna did increase after the scandal compared to before the scandal. Klarna’s visibility was also shown to increase through the higher number of customer reviews after the scandal. The measurements for corporate reputation of Klarna rose significantly after the scandal in comparison to before the scandal indicating that also Klarna’s reputation was positively affected by the scandal. The conclusion is that it is better to be infamous than unknown since there was something to gain from the scandal in terms of visibility and corporate reputation.
22

INVESTIGATING DIMMING OF OBSTRUCTION LIGHTS IN A SWEDISH WIND FARM

Jansson, Anton January 2016 (has links)
The demand and need for alternative obstruction marking has become a significant challenge for the wind power development in Sweden. While the development of wind turbines pushes for higher heights, the need to denote them as possible obstacles for aviation increase. To reduce undesired effects of the aviation warning lights in the landscape, various technologies for reducing the light emitted have been developed. One of these technologies control the lights’ output by dimming them based on measurements of the prevailing visibility in the vicinity of the wind farm.Visibility controlled obstruction lighting has not yet been used in Swedish wind farms. This thesis will investigate how a system can be applied from different viewpoints and what would be gained in a wind farm in northern Sweden.By reviewing literature, interviewing key-persons, studying a case with application of Finnish regulations and estimating the performance during different conditions, and discussing the results, conclusions could be drawn. The findings are general recommendations for acceptance, an aviation risk that need to be considered, indications of preferable regulation applications and approximations of the performance and possible gain.
23

A fog and low visibility climatology for selected stations in the Western Canadian Arctic

Khalilian, Vida 06 January 2017 (has links)
A detailed examination of low visibility (LV) occurrences and the weather types that cause low visibility, with a focus on fog, was performed for five weather stations in the western Canadian Arctic, in the vicinity of the Amundsen Gulf area of the eastern Beaufort Sea. A series of climatologies were developed that established patterns of LV occurrence as a proportion of all observations and as a function of LV events caused by fog. Frequency climatologies for other weather types were also performed; in particular, for snow, blowing snow, rain, and drizzle. Annual climatologies were used to identify trends in several weather parameters over the 1980-2015 period of study. Monthlies were used to identify typical patterns of occurrence over the course of a year, and hourlies over the course of a day. A dataset of multi-hour fog events was also created; some of these were related to synoptic patterns. Analysis was also broken down by season. Results indicate several things. Monthly climatologies showed considerable diversity across the study area. Three distinct groupings were noted: Tuktoyaktuk and Ulukhaktok with a maximum frequency of LV conditions in February, Aklavik and Inuvik with a maxiumum frequency in October, and Sachs Harbour in August. The February maximum in Tuktoyaktuk and Ulukhaktok was related to cold air temperatures combined with small amounts of moisture from sea ice leads. The Alkavik and Inuvik October maximum was related to moisture advected over land from remaining open water, as well as diurnal snow melt adding moisture to the boundary layer that condenses as the evening cools off. The August maximum in Sachs Harbour is a reflection of proximity to open water and cold air temperatures. Hourly climatologies in the spring/fall season showed most stations have maximum occurrence of LV events caused by fog in the early morning. This is a radiative effect; cooling overnight causes radiation fog that peaks in occurrence just as morning begins. This peak is pushed into the midday in the winter, and is much weaker in the summer, both reflections of the changing pattern of daylight hours. / Graduate
24

Efektivní výpočet viditelnosti pro simulaci přenosu světla v opticky aktivních médiích / Efficient visibility calculation for light transport simulation in participating media

Houška, Čestmír January 2013 (has links)
Title: Efficient visibility calculation for light transport simulation in participating media Author: Čestmír Houška Department / Institute: Department of Software and Computer Science Educa- tion Supervisor of the master thesis: doc. Ing. Jaroslav Křivánek, Ph.D. Abstract: This thesis investigates the use of acceleration methods for the testing of visibility in light transport calculation algorithms with the emphasis on conser- vativeness and low accelerated query overhead. Several published non-directional and directional distance field methods are presented with the description of their characteristic properties. Two of these methods are then implemented and thor- oughly tested in an existing rendering framework on a path tracing volumetric integrator as well as on an own implementation of a ray marching single scattering integrator. A method that further accelerates the original distance field methods by pre-caching results of some of the queries is also proposed, implemented and tested. Furthermore, several possible extensions to this method are outlined. Keywords: computer graphics, rendering, participating media, visibility
25

Flying Under the Radar: the Politics of Low-visibility Retrenchment. A Case Study Involving the United Kingdom and the Federal Republic of Germany

Baum, Christopher J. January 2009 (has links)
Thesis advisor: Kenji Hayao / This paper discusses the forces driving variation in the success of state pension system retrenchment. Two case studies are presented: the United Kingdom’s largely successful effort in 1986, and Germany’s less than stellar effort in 2001. After examining the general impact of institutional effects, ideology, path dependency, and demographic pressures on retrenchment, the importance of these factors in each country is discussed. These two countries are particularly enlightening due to their prototypical natures and opposing democratic traditions. One objective of this paper is to explain an unexpected outcome: the successful retrenchment produced in a low-pressure environment in the U.K., and ineffective reform in Germany in a high-pressure environment. This discussion frames the factors that determine successful retrenchment as such: whether a government has the ‘will,’ or motive, to retrench, whether it has the capability to do so, and whether it has the awareness and acumen to implement low-visibility strategies. I find that low-visibilities are extremely important to success in this area, and due to the nature of pension policy, the implications of this conclusion may be applicable to other policy-making challenges. / Thesis (BA) — Boston College, 2009. / Submitted to: Boston College. College of Arts and Sciences. / Discipline: College Honors Program. / Discipline: Political Science Honors Program. / Discipline: Political Science.
26

Connections between the hillforts of the Clwydian Range and the wider landscape

Lloyd Jones, Erin January 2019 (has links)
This study examines the characteristics and setting of the six hillforts of the Clwydian Range in north east Wales and considers other hills and hillforts within the surrounding area. It provides an assessment of the hillforts of much of north Wales and the borderlands as a group, to define connections or regional variations, in order to aid understanding of their function. Sites have been investigated through the use of Geographical Information Systems and viewshed analysis to consider the extent of view, the features visible and intervisibility. The use of a control sample of non-hillfort sites considers why some hills were chosen to be hillforts but others not. Interrogation of the data to identify what the monument can see, not just how much, is fundamental in the interpretation of site selection and position. Architectural features and dating evidence have been documented and examined. Former radiocarbon dating has been scrutinised and recalibrated to ensure consistency. A theme of stone, or the illusion of, is dominant across the study area and, despite previous reports, not limited to Gwynedd and a small number of outliers. Entrances and their evolution are distinctive to north east Wales and the borders, with possible links to northern England. The hillforts of the Clwydian Range are distinctive with regards to their proximity and longevity, with multi-phase, multi-period use. In contrast to 'Central Place Theory', there is not an obvious 'main' hillfort dominating or suppressing the others. Instead, awareness of each other may have complimented their situation and therefore the area flourished. Changes in the hillforts' characteristics are essential in understanding the evolution of their function throughout the Iron Age; from initial community links and cultivation, to control and finally to conservation, which is a tradition which has continued to this day.
27

Application of Artificial Neural Network on The Prediction of Ambient Air Quality

Lin, Yat-Chen 30 July 2002 (has links)
The air quality in Kaohsiung and Ping-Dong district is the worst in Taiwan. The air pollution episodes in Kaohsiung are attributed to high concentrations of PM10 and O3. Among them, over half of the episodes result from PM10. In addition to Pollutant Standards Index (PSI), atmospheric visibility is also an indicator of ambient air quality. Citizens always complain about the impairment of visibility because it can be visualized directly. Visibility is closely correlated to both air pollutants and meteorological condition. Extinction of visible light by fine particles is the major reason for visibility impairment. In this study, an artificial neural network was applied to predict the concentration of PM10 and atmospheric visibility. The objectives of this study were to investigate the effects of meteorological factor and air pollutants on visibility and to apply artificial neural network to predict the concentration of PM10 and atmospheric visibility. The measured PM10 data were divided into two parts (i.e. summer and winter, ) to understand whether different season affect the prediction of PM10 concentration. The modeling results showed that the optimum input variables included the PM10 concentration, atmospheric pressure, surface radiation, relative humidity, atmospheric temperature, and cloud condition. The network outputs showed high correlation with measured PM10 concentration (R=0.876) in the whole-year set. Furthermore, the prediction of summer set also showed high correlation with measured PM10 concentration (R=0.753). The winter set demonstrated the worse prediction among three sets, and showed medium correlation with measured PM10 concentration (R=0.553). The visibility network test was conducted by two stages. The first stage (set-1~set-3) showed that relative humidity, atmospheric temperature, and cloud condition were the most important meteorological factors, while PM10, O3, and NO3 were the most important air pollutants on the prediction of atmospheric visibility. The prediction of set-1 considering only meteorological factors was the worst (R=0.586), while set-3 was the best and showed medium correlation with measured atmospheric visibility (R=0.633). The second stage (set-4 and set-5) increased the hidden neuron numbers and input variables, and added atmospheric visibility in the input variables. Although the correlation coefficients between predicted and measured data did not increase, the prediction of atmospheric visibility had significant improvement. Finally, a short-term prediction of PM10 and atmospheric visibility was conducted and validated by the level of PSI values and atmospheric visibility. Prediction results showed that the accuracy of PM10 prediction was 76.9%, while the prediction of atmospheric visibility by set-3 network demonstrated an accuracy of 76.9%. Moreover, no significant difference of prediction was detected by using either three-level or five-level visibility systems.
28

Air Visibility Forecasting via Artificial Neural Networks and Feature Selection Techniques

Yang, Tun-Hsiang 01 August 2003 (has links)
none
29

Changing visibility in Kuwait: 1963-1978

Nasrallah, Hasan Ali January 1980 (has links)
No description available.
30

High resolution phase contrast x-ray radiography

Arhatari, Benedicta Dewi January 2006 (has links) (PDF)
The conventional approach for x-ray radiography is absorption contrast. In recent years a new approach that eliminates the usual requirement for absorption and allows the visualization of phase based on refractive index features in a material has been demonstrated. This so-called “phase contrast imaging” has now been applied using a wide range of radiation and samples. In this work we are motivated by the need to find optimal conditions for achieving high quality phase contrast images. We consider image formation using the free space propagation of x-rays from a point source passing through a sample. This imaging model is a lens-less configuration and, as such, is very useful for x-ray wavelengths where lenses are difficult to fabricate. Although no lenses are used, image magnification is still achieved due to the expansion of the wavefront as it propagates from the point source illumination. The short wavelength and penetrating power of x-rays make them ideal for non-destructive studies of microscopic samples. However, these techniques are also important for investigating larger, non-microscopic samples.

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