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Strategy development is one of the crucial factors for a firm's performance. For it
to be developed, a strategic analysis has to be conducted first. It enables
companies to gain a deeper understanding of their internal and external
environment. In the present work, the specialty coffee market is closely analyzed through a strategic analysis. The focus of this study is the young company Tikuna, a coffee producer that aims to enter the German market. In this context, Tikuna's possible entry into the German market and the companies competitive capacities are analyzed. In order to implement the different tools of the analysis, extensive literature research, as well as one expert interview and a survey were conducted.
It was found that Tikuna possesses all characteristics to enter the German
market. However, due to the lack of a differentiation factor in Tikuna's value
proposition, its competitive capacity is limited to a short period of time. In this
sense, different recommendations are given in order to ensure long term success
in the market. The central one being that Tikuna has to use its main strength and
bring innovation to the market.
This paper aims to provide essential information about the formal aspects of the adjustment process companies in Southern Germany utilize to adjust their employees to new surroundings. In particular, it shall be investigated and defined what formal aspects are and when firms apply them. Literature shows that companies do implement language courses, intercultural trainings or provide further information about the host country before a stay abroad. Nevertheless, the phases during and after the assignment are not taken into account with the required importance. Additionally, since national culture can be broken down into different layers, the organizational culture as one layer was analyzed, too.By conducting a quantitative research among companies in Baden-Württemberg, this paper shows the different approaches for dealing with a stay abroad. Scientific literature about the topic of adjustment of globally assigned workers shall help emphasizing the need of a deeper cultural insight. Furthermore, by attempting to explain the organizations’ culture, a better understanding of the chosen training methods shall be created. Definitions in the beginning helped to understand the concept of culture, the notion and the phases of adjustment. Almost all collected data has been accessed either through JSTOR (a digital library founded to help academic libraries or publishers) or similar databases, through the companies’ websites or through the survey results it selves.The results of this research show that the phase before the stay abroad is organized well. Companies offer pre-departure training, but during and after the expatriate time a lack of support is being observed. The firms obviously underestimate the necessary help needed during the assignment and in the return phase, which is why the thesis attempts to fill this gap. Through the organizational culture, described on the companies’ webpages the author was able to draw a conclusion to the applied training methods, which results in a consistent overall picture of the described firms. Companies from the automotive sector had the highest return rate in the survey, which is why particular attention was paid to it.
This paper describes an application analysis of one important topic of diversity
marketing – gender marketing. With the help of two surveys and content analyses
in two different media sectors – television and print media – the general trend of
gender representation in advertising could be located. While most survey
respondents are still using characteristics for males and females which were
shaped by traditional gender roles, most of them believe that the roles from the
1950s are outdated and that the media should adapt to the changes in societies in
regard to gender roles. However, the content analyses have shown that the
marketers have already adapted and are primarily presenting the viewers
contemporary images of men and women instead of the stereotyped ones from the
1950s. The only issue that has not changed yet is the color coding which starts to
differentiate between males and females since childhood. The findings of this
paper suggest that the perception and the reality do not always correspond with
each other and that, although the adoption of the change of gender roles is
advancing, it is still not completed yet.
This research looks into the question of where and how Artificial Intelligence and Big Data can be usefully implemented into Affiliate Marketing. By consulting relevant literature and qualified experts, this work identifies 6 areas, where Artificial Intelligence can be beneficial. These areas were found to be Affiliate Recruitment, Affiliate Management, Product Data Feed Optimization, Tracking, Attribution and Forecasting.
The implementation of Artificial Intelligence in these areas revealed 3 advantages to the Affiliate Marketing channel: Saving of time, support of decision-making, and incentivizing of publishers. While a more detailed study of this research topic would be necessary for validating the results, the findings show that the implementation of Artificial Intelligence technology can help a business gain competitive advantage.
Purpose: Although the frequency in which practitioners are fitting scleral
contact lenses is increasing, the recommendation for proper tear layer depth
(thickness) varies amongst experts. The main goal of this paper is to clinically
verify the effect of varying tear layer depths on induced corneal edema during
lens wear.
Methods: Ten subjects with healthy eyes were fitted with scleral lenses on their
right eye. Each of them was fit with two different lenses: one with an apical
clearance of 200 μm and another with an apical clearance of 600 μm. They wore
the lenses for 8 hours on two different days, with at least a one week wash-out
period. Lenses were applied at 8 a.m. on each of the testing days. Pachymetry
measurements were taken one day prior to lens wear at 4 p.m., on the day of
wear prior to lens application, and after removal of the lenses at 4 p.m.
Measurements were collected using both the Pentacam® HR Corneal
Tomographer, as well as the Visante Anterior Segment Optical Coherence
Tomographer (OCT). The apical clearance was measured using the
Visante OCT at two intervals during the test day: immediately after application of
the lens and immediately prior to the removal of the lens.
Results: In this study, there was found to be no significant difference in corneal
edematous response during lens wear between the two test groups. The study
shows that the eyes with the lenses have a statistically significantly thicker
cornea compared to the non-lens-wearing eye after wearing either lens for 8
hours, lying within clinically and physiologically acceptable limits.
Conclusion: Our clinical results do not correlate with current theoretical
calculations, which predict a greater amount of corneal swelling with increasing
tear layer thickness. It has to be evaluated if the effect on corneal edema
changes with longer wearing periods, larger samples or other influences.
Key words: scleral (contact) lens, corneal edema, pachymetry, tear layer
thickness, vaulting, apical clearance
The surface topography of biodegradable polymer foils is modified by mechanical imprinting on a submillimeter length scale. The created patterns strongly influence the wetting behavior and allow the preparation of hydrophobic surfaces with controlled solid-liquid interaction. A detailed analysis of anisotropic surface patterns reveals that the observed effect arises from a combination of topographical and compositional changes that are introduced to the surface. As a main result it is found that an individual combination of material and structure is required for the production of water-repellent biopolymer foils that are highly attractive for packaging applications.
The present study deals with the topic how a town can use its cultural heritage or,
more precisely, its industrial culture as a means to market itself as an innovative
business location and to foster a more pronounced sense of civic cohesion among
residents. Economic theory suggests that, nowadays, traditional location factors
such as access to resources and a performant infrastructure are less important than
in the industrial age. Recently, factors like a city’s potential to generate and retain
human and creative capital have emerged. Accordingly, the economic and social
role of cities has shifted – from a place where workers lived and manufactured
goods towards a deeply interwoven ecosystem of knowledge-intense value creation.
The question at the root of the present study is how Heidenheim’s rich industrial
cultural heritage can be used as a future-pointing source of power for rebranding
the town. This rebranding concept has to be developed according to the town’s role
in past, present and future, thus creating actual economic and societal value.
Industrial culture bears branding potential and is closely related to various aspects
of modern life and work. The study examines possibilities to create awareness for
these relations connecting past, present and future. Their relevance shall be
emphasized in order to establish both points of orientation and authenticity of place
in times when macroeconomic and societal trends are difficult to predict. Ideally,
residents shall be given a sort of local identification to hold on to, and potential
investors and entrepreneurs shall be encouraged to sustainably experience the
innovation-based DNA of Heidenheim. Therefore, the study searches for a value
proposition that takes into account the points mentioned above on terms of an
innovative theoretic framework. As a result of this thesis, precise suggestions for
the implementation of a new branding strategy based on the conceptual guidelines
developed in this study will be proposed to the municipality of Heidenheim and, in
addition, an interface using principles of virtual and augmented reality will be
introduced.
Based on a data-driven approach, a computer-assisted workflow for the quantitative analysis of optical Kerr microscopy images of sintered FeNdB-type permanent magnets was developed. By analyzing the domain patterns visible in the Kerr image with data-driven approaches such as traditional machine learning and advanced deep learning, we can quantify grain orientation and size with a better trade-off between accuracy and higher throughput than electron backscatter diffraction (EBSD). The key distinction between traditional machine learning and advanced deep learning lies in feature extraction. Traditional methods require manual, user-dependent feature extraction from input data, while advanced deep learning achieves this automatically. The predictions from the trained models were compared to the measurements from EBSD for performance evaluation. The proposed data-driven model is trained on the dataset created from the correlative microscopy technique, which requires the images of grains extracted from the Kerr microscopy and corresponding EBSD grain orientation data (Euler angles). The fine-tuned deep learning model shows better generalization ability than the traditional machine learning models trained on the manually extracted features and resulted in a mean absolute error of less than 5° for grain orientation of the anisotropic magnet samples when evaluated against the measured EBSD values. The developed approach has reduced the measurement effort for grain orientation by 5 times and have sufficient accuracy when compared to the EBSD.
Purpose
To determine the stereo threshold and inherent variability with a monitor-based two-rod test at various eccentricities of the visual field. Additionally, to evaluate the duration of this procedure.
Subjects and methods
A pilot trial was conducted in five ophthalmologically normal subjects (2 male and 3 female) aged 21 – 23 years. Two black rods on white background, which appeared under an angle of 1° were presented in a viewing distance of 5.0 meters. The right rod was stationary, whilst the left rod appeared under a stereoscopic parallax, with an either proximal or distal displacement to the image plane. Threshold determination was assessed at seven eccentricities of the visual field by a staircase method. Eccentricities were 0° centrally, 5° to the right and left, 10° to the right and left and 15° to the right and left of the visual field. Proximal and distal displacement as well as the sequence of eccentricities were presented in random order. Stereo acuity was measured in two different sessions for four subjects and in five different sessions for one subject. For all sessions the duration was recorded. All sessions were separated by a time interval of at least 24 hours and no longer than 7 days. Evaluation was made by Wilcoxon test and Kruskal Wallis test at the 95% confidence level (CI) and the median was assessed for all thresholds.
Results
Stereo acuity declines with increasing eccentricities of the retina similar to visual acuity. While at 0° eccentricity thresholds were found to be lowest with (median) 5.0 seconds of arc (‘’) and the CI (0.5’’, 30.5’’) for all measurements, they increased to 112.2’’ at 15° eccentricity to the left in proximal displacement. Distal it was 19.9’’ centrally and 112.2’’ to the right at 15° eccentricity with CI (0.5’’, 30.5’’) for all measurements.
Repeatability of the threshold determination was found to be best at 0° eccentricity with proximal displacement showing the exact same result in the repetitive session and poorest repetition was found at 15° eccentricity to the left with distal displacement. Distal repeatability was worse than proximal. Median and CI of duration time was 5.3 (3.2, 8.3) minutes.
Conclusion
Stereo acuity thresholds are repeatable however increase with increasing eccentricity. Repetitions of the threshold determination do not vary considerably. The duration of these measurements indicates the monitor-based two-rod test as a fast procedure, that can be applied in future studies. The test program is limited by an imperfect algorithm and the stereoscopic images evoke cues, this should be reworked.
Transformations in the work–nonwork interface highlight the importance of effectively managing the boundaries between life domains. However, do the ways individuals manage the boundaries between work and nonwork life change from one day to the next? If so, which antecedents may explain these intra-individual fluctuations in boundary management? Drawing on boundary management, spillover, and resource theories, we investigate daily changes in segmentation preferences and integration enactments as a function of experiencing strain in work and nonwork life. Assuming that changes in segmentation preferences reflect an individual’s strategy to regulate negative cross-role spillover, we suppose that strain increases individuals’ segmentation preferences; at the same time, however, it could force individuals to enact more integration.
The present thesis deals with alternative powertrains, focusing on electric vehicles
and hybrid vehicles and which of those alternative powertrains is considered as
sustainable for the future. It explores the question, which alternative powertrain is
worthwhile investing in for German automotive suppliers. The aim is to clarify
which of the two powertrains is already established on the market and what the
future prospects of those powertrains are. The question here is evaluated based on
the analysis of current literature as well as through the use of a SWOT analysis
and the use of the scoring model.
As a result it is clear that there is a need for alternative powertrains and the entire
automotive industry invests a lot in the development and research of alternative
powertrains. According to the German Federal Government, one million electric
vehicles should be on German roads by 2020. With pure electric vehicles, however,
the goal will be difficult to reach. Therefore, there is a lot of vested interest in
the development of hybrid vehicles on the market. It shows that the hybrid vehicle
has considerable advantages over the electric vehicle and the hybrid vehicle is
already seen as a transitional solution for pure electric vehicles. The hybrid vehicle
is also already established in the market and has better chances on the market
in the future. Therefore, it makes sense for German automotive suppliers to invest
in hybrid vehicles and to focus on this market, since there the chances of success
are greater and the future potential of this market is higher.
Purpose
Automated scanpath comparison metrics should deliver an objective method to
evaluate the similarity of scanpaths. The aim of this thesis is an evaluation of
seven existing scanpath comparison metrics in static and dynamic tasks in order
to provide a guidline that helps to decide which algorithm has to be chosen for a
special kind of task.
Methods
The applicability of the algorithms for a static, visual search task and a dynamic,
interactive video game task as well as their constraints and limitations were tested.
Therefore, binocular gaze data were recorded by using the eye tracking system The
Eye Tribe (The Eye Tribe ApS, Copenhagen/ Denmark). Objective task performance
measures from 21 subjects were used in order to create scanpath groupings
for which a relevant effect of dissimilarity was to be expected. Objective task performance
measures such as task performance time were statistically evaluated and
compared to the results gained by the comparison metrics.
Results
Four of the algorithms being used successfully identified differences for static and
dynamic tasks: MultiMatch, iComp, SubsMatch and the Hidden Markov Model.
ScanMatch was very sensitive for the static task but not applicable to the dynamic
task whereas FuncSim was suitable for dynamic but not for static tasks. Eyenalysis
failed to detect any effect.
Conclusion
The applicability of scanpath comparison metrics depends on the state of the task,
respectively on the kind of experimental set up. In future, the application area for
eye tracking will expand and an improvement of automated scanpath comparison
metrics is therefore required.
This paper deals with the question of which factors have to be given for
successful share repurchases that create long-term shareholder value. Center of
the thesis is the agency theory and its influence on share repurchases. Based on
theoretical findings success factors for share repurchases are derived and then
verified by case studies.
The main drivers for a successful share repurchase elaborated by this paper are a
suitable long-term executive compensation, an independent board of directors and
a shareholder structure without a majority shareholder. Additionally the findings
show that tying repurchases to certain share price thresholds improves the quality
of share repurchases.
The increasing prevalence of myopia throughout the industrialized world in recent decades has caused costs and problems for the eye health. Changed lifestyle and behavior are the main causes. For the pathogenesis of myopia, the amount of time spent outdoor and near activities play an important role. Various options for the treatment of myopia have been described as effective in the literature. Normal single vision glasses and contact lenses can only provide clear vision, but do not reduce myopia progression. Orthokeratology shows a slowing of axial growth, but has an increased risk of infectious keratitis. Low-dose atropine (0.01%) is currently the best pharmacological option. It proved safe, effective and showed the least rebound effect with negligible side effects. Other options for the treatment of myopia include special glasses, behavioral changes and prolonged outdoor exposure (to prevent the onset of myopia), as well as other methods. An increasingly important myopia management option is multifocal contact lenses, that provide a peripheral treatment zone producing myopic defocus. Such myopia control lenses are available as customized or as daily or monthly lenses. Children benefit from wearing contact lenses more than just having refractive error correction and myopia control, they have a better self-esteem and improved quality of life. The numerous findings on the safety and efficacy of soft multifocal distance center contact lenses in children to reduce the progression of myopia suggest that this modality should be considered as a main treatment option. Less, but similar to orthokeratology, when wearing soft lenses there is a risk of developing potentially serious complications such as microbial keratitis. The introduction of child-appropriate risk minimization strategies, and patient and parent education with regular monitoring is essential and leads to successful contact lens wear. This literature review summarized the actual knowledge about myopia management, prevalence, etiology and the visual and healthy consequences of myopia.
The three currently most important strategies for slowing the progression of myopia are soft multifocal distance center contact lenses, Orthokeratology and low-dose atropine ophthalmic drops.
Abstract
1.1 Purpose
The purpose of this study is to prescribe follicular-like conjunctivitis associated with Siliconhydrogels
(FoCoSi) in silicone hydrogel contact lens wearers as a novel subtype of
the well prescribed contact lens induced papillary conjunctivitis (CLPC).
1.2 Methods
1211 patients who wore silicon hydrogels were included in this prospective, nonrandomised,
single center study. Subjective symptoms and clinical signs were evaluated
for daily wear (DW) and continuous wear (CW) populations for several (Lotrafilcon A,
Lotrafilcon B, Senofilcon A, Galyfilcon A) silicon hydrogel lens types. CCLRU and other
specifically developed grading scale were utilized for evaluation. Grading of 2 and above
was rated as clinically significant. Statistical evaluation was performed for eyes rather
than subjects.
1.3 Results
The clinical presentation of FoCoSi could be confirmed and showed an incidence of
3.8%. Lotrafilcon A followed by Senofilcon A on a CW modality presented, with a risk
ratio of 2.49 and 1.53 respectively, the highest affinity for developing FoCoSi. Fluorescein
positive spots showed the closest correlation with subjective symptoms reported
by patients and divided FoCoSi into an active and dormant form. Besides Protein, Lipid
deposition on the contact lens surface and air pollution like Ozone or fine and ultrafine
particles seems to be important factors in developing FoCoSi, whereas mechanical irritation
played a minor role.
1.4 Conclusion
FoCoSi is a novel and relevant subtype of CLPC. Further studies should be performed
to validate these findings and clear up several questions about the aetiology of FoCoSi
and CLPC.
Keywords: Giant papillary conjunctivitis (GPC), contact lens-induced papillary conjunctivitis
(CLPC), follicular-like conjunctivitis associated with siliconhydrogels (FoCoSi)
In the fast-growing but also highly competitive market of battery-powered power tools, cell-pack-cooling systems are of high importance, as they guarantee safety and short charging times. A simulation model of an 18 V power tool battery pack was developed to be able to evaluate four different pack-cooling systems (two heat-conductive polymers, one phase change material, and non-convective air as reference) in an application scenario of practical relevance (the intensive use of a power tool followed by cooling down and charging steps). The simulation comprises battery models of 21700 cells that are commercially available as well as heat transfer models. The study highlights the performance of the different cooling materials and their effect on the maximum pack temperature and total charging cycle time. Key material parameters and their influence on the battery pack temperature and temperature homogeneity are discussed. Using phase change materials and heat-conductive polymers, a significantly lower maximum temperature during discharge (up to 26%) and a high shortening potential of the use/charging cycle (up to 32%) were shown. In addition to the cooling material sweep, a parameter sweep was performed, varying the external temperature and air movement. The high importance of the conditions of use on the cooling system’s performance was illustrated.
A good stereopsis (depth perception) is needed in everyday life, regardless whether a person is a professional driver or chef. Good estimation of distance, and of what is further and what closer, could mean the difference between a crushed and a whole car or between a bloody and a healthy finger. The main theme of this Master thesis is detect and quantify major factors in depth perception. Do the younger estimate the depth better than the older; do they have better depth perception with greater or smaller pupil distance; does depth perception depend on gender; what happens with stereopsis when vision is fogged by +0,5 and +1,0 D? These are the questions dealt with in this Master thesis.
To answer these questions measurements were made on 51 subjects (mean age 45,0 +/- 13,32 years) of whom 25 were women, mean age 45,5 +/-13,55 years (12 with PD<62 mm, mean and 13 with PD>66 mm) and 26 men, mean age 44,4 +/- 13,34 years (13 with PD<62 mm and, 13 with PD >66 mm). Each of these four groups was further divided by age (one in range 20 to 35 years and second in range 50 to 65 years).
The measurements were made with a few assumptions. The first assumption was that stereopsis is in direct correlation with visual acuity, the second assumption was that persons with bigger interpupillar distance have better stereopsis, and the third assumption was that with age the stereopsis ability decreases.
The measurements were done with modified Frisby–Davis test expanded from four geometrical shapes to twenty-five circles. The stereopsis was measured with full refractive correction at 4,5 and 3,0 meters. Later, stereopsis was measured with fogging with +0,5 and +1,0 D at the 4,5 and 3,0 meter distances.
Statistically there is no correlation (or very weak) between stereopsis and the visual acuity for whole group of 51 test persons, but if only young test persons are taken in consideration, the correlation becomes significant, r(20)=0,566, p=0,009 at 4,5 m and r(20)=0,456, p=0,043 at 3,0 m and that matches the assumption. Stereopsis is in no or weak positive correlation with pupil distance r(51)=0,059, p=0,679, which is in total contrast to the assumption. Stereopsis is in positive correlation with age at 4,5 meters measuring distance, r(51)=0,371, p=0,007, which corresponds to assumption. In addition, stereopsis is better in females than in males by 32,5%.
Based on the results it can be concluded that the stereopsis is in negative correlation with age, in positive correlation with visual acuity, females have better stereopsis than males and statistically, the correlation between stereopsis and pupil distance (PD) has not been proved. The most important conclusion is that the decreased visual acuity brings significant fall of stereopsis. A deficit in refraction of -0,50 D decreases stereo acuity by about 90% (nearly 2x) and a deficit of -1,0 D decreases stereo acuity by about 220% (about 3x).
Keywords: Stereopsis, stereo acuity, depth perception, pupil distance (PD), visual acuity (VA).
Laser melting manufacturing of large elements of lunar regolith simulant for paving on the Moon
(2023)
The next steps for the expansion of the human presence in the solar system will be taken on the Moon. However, due to the low lunar gravity, the suspended dust generated when lunar rovers move across the lunar soil is a significant risk for lunar missions as it can affect the systems of the exploration vehicles. One solution to mitigate this problem is the construction of roads and landing pads on the Moon. In addition, to increase the sustainability of future lunar missions, in-situ resource utilization (ISRU) techniques must be developed. In this paper, the use of concentrated light for paving on the Moon by melting the lunar regolith is investigated. As a substitute of the concentrated sunlight, a high-power CO2 laser is used in the experiments. With this set-up, a maximum laser spot diameter of 100 mm can be achieved, which translates in high thicknesses of the consolidated layers. Furthermore, the lunar regolith simulant EAC-1A is used as a substitute of the actual lunar soil. At the end of the study, large samples (approximately 250 × 250 mm) with interlocking capabilities were fabricated by melting the lunar simulant with the laser directly on the powder bed. Large areas of lunar soil can be covered with these samples and serve as roads and landing pads, decreasing the propagation of lunar dust. These manufactured samples were analysed regarding their mineralogical composition, internal structure and mechanical properties.