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To create a map of an unknown area, autonomous robots must follow a strategy to explore the area without knowing the optimal paths to reduce the time needed to map the whole area. To reduce the time to accomplish this task, multiple robots can work together to create a map in a more efficient way. However, without proper coordination, the time a team of autonomous robots needs to explore the unknown area can exceed the time needed by a single robot. To counteract the challenges, a shared infrastructure is needed which extracts useful information for the individual robots out of the shared information of all robots so the exploration can be coordinated. These measures introduce new challenges to the system, concerning the load of the communication infrastructure as well as the overall task of exploring and mapping becoming dependent on the correct communication and robustness of the shared team infrastructure. Therefore, the amount of communication and dependency of each individual robot of the rest of the other robots of the team must be reduced to ensure that the robots can continue working even if the communication with the shared infrastructure fails.
In recent years, numerous studies around the world have examined the environmental potential of biochar to determine whether it can help address climate challenges. Several of these studies have used the Life Cycle Assessment (LCA) method to evaluate the environmental impacts of biochar systems. However, studies focus mainly on biochar obtained from pyrolysis, while the number of studies on biochar from gasification is small.
To contribute to the current state of LCA research on biochar from gasification, LCA was performed for biochar, electricity, and heat from a wood gasification plant in Vorarlberg, Austria. Woodchips from local woods are used as biomass feedstock to produce energy, i.e., electricity and heat. Thereby, biochar is obtained as a side product from gasification. The production of syngas and biochar takes place in a floating fixed-bed gasifier. Eventually, the syngas is converted to electricity in a gas engine and fed to the power grid. Throughout different stages within the gasification process, heat is obtained and fed into local heat grid to be delivered to customers. The biochar produced complies with the European Biochar Industry (EBI) guidelines and is used on a nearby farm for manure treatment and eventually for soil application. Thereby, the effect of biochar used for manure treatment is considered to reduce emissions occurring from manure, i.e., nitrogen monoxide (N2O). Further, the CO2 sequestration potential of biochar, i.e., removal of CO2 from the atmosphere and long-term storage, is considered. Several constructions, such as the construction of the gasification system and the heating grid, are included in the evaluation.
As input related reference flow, 1 kg of woodchips with water content of 40 % is used. Three functionals units are eventually obtained, i.e., 0.17 kg of biochar applied to soil, 4.47 MJ of heat and 2.82 MJ of electricity, each per reference flow. The results for Global Warming Potential (GWP) for biochar is – 274.7*10 - 3 kg CO2eq per functional unit, which corresponds to – 1.6 kg CO2eq per 1 kg biochar applied to soil. The GWP for heat results in 17.1*10 - 3 CO2eq per functional unit, which corresponds to 3.6*10 - 3 kg CO2eq per 1 MJ. For electricity, a GWP of 38.1*10 - 3 kg CO2eq per functional unit is obtained, which is equivalent to 13.5*10 - 3 kg CO2eq per 1 MJ.
The calculation was performed using SimaPro Version 9.1 and the ReCiPe method with hierarchist perspective.
If left uncontrolled, electric vehicle charging poses severe challenges to distribution grid operation. Resulting issues are expected to be mitigated by charging control. In particular, voltage-based charging control, by relying only on the local measurements of voltage at the point of connection, provides an autonomous communication-free solution. The controller, attached to the charging equipment, compares the measured voltage to a reference voltage and adapts the charging power using a droop control characteristic. We present a systematic study of the voltage-based droop control method for electric vehicles to establish the usability of the method for all the currently available residential electric vehicle charging possibilities considering a wide range of electric vehicle penetrations. Voltage limits are evaluated according to the international standard EN50160, using long-term load flow simulations based on a real distribution grid topology and real load profiles. The results achieved show that the voltage-based droop controller is able to mitigate the under voltage problems completely in distribution grids in cases either deploying low charging power levels or exhibiting low penetration rates. For high charging rates and high penetrations, the control mechanism improves the overall voltage profile, but it does not remedy the under voltage problems completely. The evaluation also shows the controller’s ability to reduce the peak power at the transformer and indicates the impact it has on users due to the reduction in the average charging rates. The outcomes of the paper provide the distribution grid operators an insight on the voltage-based droop control mechanism for the future grid planning and investments.
In recent years, ultrashort pulsed lasers have increased their applicability for industrial requirements, as reliable femtosecond and picosecond laser sources with high output power are available on the market. Compared to conventional laser sources, high quality processing of a large number of material classes with different mechanical and optical properties is possible. In the field of laser cutting, these properties enable the cutting of multilayer substrates with changing material properties. In this work, the femtosecond laser cutting of phosphor sheets is demonstrated. The substrate contains a 230 micrometer thick silicone layer filled with phosphor, which is embedded between two glass plates. Due to the softness and thermal sensitivity of the silicone layer in combination with the hard and brittle dielectric material, the separation of such a material combination is challenging for both mechanical separation processes and cutting with conventional laser sources. In our work, we show that the femtosecond laser is suitable to cut the substrate with a high cutting edge quality. In addition to the experimental results of the laser dicing process, we present a universal model that allows predicting the final cutting edge geometry of a multilayer substrate.
Entangled photon generation at 1550 nm in the telecom C-band is of critical importance as it enables the realization of quantum communication protocols over long distance using deployed telecommunication infrastructure. InAs epitaxial quantum dots have recently enabled on-demand generation of entangled photons in this wavelength range. However, time-dependent state evolution, caused by the fine-structure splitting, currently limits the fidelity to a specific entangled state. Here, we show fine-structure suppression for InAs quantum dots using micromachined piezoelectric actuators and demonstrate generation of highly entangled photons at 1550 nm. At the lowest fine-structure setting, we obtain a maximum fidelity of 90.0 ± 2.7% (concurrence of 87.5 ± 3.1%). The concurrence remains high also for moderate (weak) temporal filtering, with values close to 80% (50%), corresponding to 30% (80%) of collected photons, respectively. The presented fine-structure control opens the way for exploiting entangled photons from quantum dots in fiber-based quantum communication protocols.
Arrayed Waveguide Grating (AWG) is a passive optical component, which have found applications in a wide range of photonic applications including telecommunications and medicine. Silica-on-Silicon (SoS) based AWGs use a low refractive-index contrast between the core (waveguide) and the cladding which leads to some significant advantages such as low propagation losses and low fiber coupling losses between the AWG waveguides and the fibres. Therefore, they are an attractive DWDM solution offering higher channel count technology and good performance characteristics compared to other methods. However, the very low refractive-index contrast means the bending radius of the waveguides needs to be very large (on the order of several millimeters) and may not fall below a particular critical value to suppress bending losses. As a result, silica-based waveguide devices usually have a very large size that limits the integration density of SiO2-based photonic integrated devices. High-index contrast AWGs (such as silicon, silicon nitride or polymer-based waveguide devices) feature much smaller waveguide size compared to low index contrast AWGs. Such compact devices can easily be implemented on a chip and have already found applications in emerging applications such as optical sensors, devices for DNA diagnostics and optical spectrometers for infrared spectroscopy.In this work, we present the design, simulation, technological verification and applications of both, the low-index contrast and high-index contrast AWGs. For telecommunication applications AWG-MUX/Demux with up to 128-channels will be presented. For medical applications the AWG-spectrometer with up to 512-channels will be presented.This work was carried out in the framework of the projects: ADOPT No. SK-AT-20-0012, NOVASiN No. SK-AT-20-0017 and AUTOPIC No. APVV-17-0662 from Slovak research and development agency of Ministry of Education, Science, Research and Sport of the Slovak Republic and No. SK 07/2021 and SK 08/2021 from Austrian Agency for International Cooperation in Education and Research (OeAD-GmbH); and project PASTEL, no. 2020-10-15-001, funded by SAIA.
A Telecom optical fibers are still being the best transmission medium of digital data and analogue signals for long distance applications. Progress in integrated photonics enables development of photonic chips with new unique properties, circuits of the future, and overcomes current limits in information and communication technologies. The packaging of photonic chips is necessary for taking them out of research laboratories into real implementation in the information and communication technology applications. One important step of packaging is effective coupling of optical radiation between telecom optical fiber with ten microns core dimension and photonic chip optical waveguide with submicron dimensions. For complex photonic chips, it is necessary to couple not one optical fiber but several optical fibers, which are arranged in fiber arrays. In this case, it is necessary to use a 6D positioning system, which allows to optimally adjust the relative position of the photonic chip and the fiber arrays. After setting the optimal relative position of the photonic chip and the fiber array, the process of their fixation follows. One possibility of fixation is gluing with an adhesive in the optical path between the photonic chip and an array of optical fibers with a refractive index close to the refractive index of the optical fiber core. This paper is focused on the experimental test set-up for the temperature characterization of fiber array to photonics chip butt coupling at 1310 nm and 1550 nm wavelengths fixed themselves by UV adhesive in the optical path. The main aims of this works are selection of better adhesive from two types for gluing of photonic chip and fiber array in packaging process of photonics chips and validation of gluing process developing. The coupling and alignment of fiber arrays to photonics chip were done by automated active alignments system and they were fixed themselves by curable epoxy adhesive. Temperature changes of coupling insertion losses are measured and investigated for two different UV adhesives during three temperature cycles from -40 °C to 80 °C in climatic chamber according to Telcordia. Spectral dependence of insertion losses were measured and compared before and after three temperature cycles for 1530 nm to 1570 nm spectral range at room temperature.
This work was supported by the Slovak Research and Development Agency under the contracts APVV-17-0662 and SK-AT-20-0017 and by the COST Action “European Network for High Performance Integrated Microwave Photonics” (EUIMWP) CA16220.
In this paper, design of 1×8 multimode interference passive optical splitter is proposed. The structure of the splitter is designed based on a silicon nitride material platform. This work aims to find the minimum physical dimensions of the designed splitters with the satisfactory optical performance. According to the minimum insertion loss and minimum non-uniformity, the optimum length of the splitters is determined.
Femtosecond laser ablation on Si generates 2D ripple structures, known as laser induced periodic surface structures (LIPSS) and pinholes. We fabricated membranes with 20 to 50 μm thickness perforated by an array of tapered pinholes up to 5 μm in diameter and 10 to 20 μm spacing. Within several micrometer the pinholes transform into hollow photonic waveguides with constant diameter from 1μm to 2μm. Such structures offer a 3D photonic coupling device for polymer Y-branch- and MMI-splitter. We measured a considerable change of electrical resistivity for 500 ppm H2 in air using Si/SiO2/TiO2 substrates with 2D LIPSS. We propose to investigate 3D waveguide arrays also for photonic-chemical sensors.
In this paper we report on the experimental test set-up for the temperature characterization of fiber array to photonics chip butt coupling at 1310 nm and 1550 nm wavelengths. The alignment and gluing of fiber arrays to photonics chip were done by automated active alignments system and they were fixed themselves by UV curable epoxy adhesive. Temperature changes of coupling insertion losses are measured and investigated for two different UV adhesives during three temperature cycles from -40 °C to 80 °C in climatic chamber. Spectral dependence of insertion losses was measured and compared before and after three temperature cycles for 1530 nm to 1570 nm spectral range at room temperature.
We present design, simulation and optimization of polymer based 16-channel, 100-GHz AWG designed for central wavelength of 1550 nm. The input design parameters were calculated applying AWG-Parameters tool. The simulations were performed applying a commercial photonic tool PHASAR from Optiwave. The achieved transmission characteristics were evaluated by AWG-Analyzer tool and show a satisfying agreement between designed and simulated AWG optical properties. Finally, the influence of the number of phased array (PA) waveguides on the AWG performance was studied. The results show that there is a certain minimum number of PA waveguides necessary to reach sufficient AWG performance.
This paper presents the design, simulation, and optimization of a 1×128 multimode interference (MMI) splitter with a silica-on-silicon channel profile. This work aims to study the influence of the different S-Bend output waveguide shapes at the end of the MMI coupler on the final optical properties. The 1×128 MMI splitters have been simulated using beam propagation method in OptiBPM software. The optical properties of all considered splitters with different shapes of outputs waveguides are discussed and compared with each other. Based on the minimum insertion loss and non-uniformity, the final shape of output waveguides, ensuring the lowest losses, is determined.
Today, optics and photonics is widely regarded as one of the most important key technologies for this century. Many experts even anticipate that the 21st century will be century of photon much as the 20th century was the century of electron. Optics and photonics technologies affect almost all areas of our life and cover a wide range of applications in science and industry, e.g. in information and communication technology, in medicine, life science engineering as well as in energy and environmental technology. However even so attractive, the photonics is not well known by most people. To motivate especially young generation for optics and photonics we worked out a lecture related to the “light” for children aged eight to twelve years. We have prepared many experiments to explain the nature of light and its applications in our everyday life. Finally, we focused on the optical data transmission, i.e. how modern communication over optical networks works. To reach many children at home we recorded this lecture and offered it as a video online in the frame of children’s university at Vorarlberg University of Applied Sciences. By combining the hands-on teaching with having a fun while learning about the basic optics concepts we aroused interest of many children with a very positive feedback.
The increasing digitalisation of daily routines confronts people with frequent privacy decisions. However, obscure data processing often leads to tedious decision-making and results in unreflective choices that unduly compromise privacy. Serious Games could be applied to encourage teenagers and young adults to make more thoughtful privacy decisions. Creating a Serious Game (SG) that promotes privacy awareness while maintaining an engaging gameplay requires, however, a carefully balanced game concept. This study explores the benefits of an online role-playing boardgame as a co-designing activity for creating SGs about privacy. In a between-subjects trial, student groups and educator/researcher groups were taking the roles of player, teacher, researcher and designer to co-design a balanced privacy SG concept. Using predefined design proposal cards or creating their own, students and educators played the online boardgame during a video conference session to generate game ideas, resolve potential conflicts and balance the different SG aspects. The comparative results of the present study indicate that students and educators alike perceive support from role-playing when ideating and balancing SG concepts and are happy with their playfully co-designed game concepts. Implications for supporting SG design with role-playing in remote collaboration scenarios are conclusively synthesised.
Debugging errors in software applications can be a major challenge. It is not enough to know that a specific error exists, but the cause of it must be found in order to be able to fix it. Finding the source of an error can be time and cost intensive. The general approach is to analyse and debug the presumably erroneous part of the software. The analysis can be accompanied by instrumentation to gather additional information during the program execution. The analysis is made more difficult by the existence of different errors categories. Each category may need to be handled individually. Especially in embedded software applications, which commonly lack features like process or memory isolation, error detection and prevention can be even more challenging. This is the kind of problem this thesis tackles. This thesis tries to support developers during debugging and troubleshooting. The main focus is on errors related to memory management and concurrency. Specific features and properties of Arm Cortex-M processors are used to try to detect errors as well as their causes. For example, the memory protection unit is used to isolate the stack memories of different tasks running in a RTOS. The thesis tries to provide as much information as possible to the developer when reporting errors of any kind. The solution developed in this thesis also contains a custom memory allocator, which can be used to track down errors related to dynamic memory management. Furthermore, a Eclipse plugin has been developed which provides assertions for array accesses to detect and prevent out-of-bound accesses. The resulting solution has been implemented in commercial embedded software applications. This ensures that the developed solution is not only suitable for newly developed applications, but also for the integration into already existing products.
A concept for a recommender system for the information portal swissmom is designed in this work. The challenges posed by the cold start problem and the pregnancy-related temporal interest changes need to be considered in the concept. A state-of-the-art research on recommender systems is conducted to evaluate suitable models for solving both challenges. The explorative data analysis shows that the article's month of pregnancy is an important indicator of how relevant an article is to a user. Neither collaborative filtering, content-based filtering, hybrid models, nor context-aware recommender systems are applicable because the user's pregnancy phase is unknown in the available data. Therefore, the proposed recommender system concept is a case-based model that recommends articles which belong to the same gestation phase as the currently viewed article.
This recommender system requires that the month of pregnancy, in which an article is relevant, is known for each article. However, this information is only available for 31% of all articles about pregnancy. Consequently, this work looks for an approach to predict the month of gestation based on the article text. The challenges with this are that only few training data are available, and the article texts of the various months of pregnancy often contain the same terms, considering all articles are about pregnancy. A keyword-based approach using the TF-IDF model is compared with a context-based approach using the BERT model. The results show that the context-based approach outperforms the keyword-based approach.
In the context of this master thesis, general tensions within the relationship between headquarters and their subsidiaries are examined using the practical example of a Swiss company with its subsid-iary in Kenya. Thereby, the influence of cultural aspects and the associated different expectations on management and leadership are emphasized. In doing so, two countries are compared which have not yet been considered in the same context. The objective of this master thesis is to develop a framework that enables the headquarter in the German speaking area of Switzerland and the sub-sidiary in the Bantu speaking area of Kenya to overcome cultural barriers and to increase mutual understanding in the business context. This will facilitate the identification of potentially dysfunc-tional aspects in the working relationship and provide a basis for optimizing the existing business relationship between the Swiss headquarter and the Kenyan subsidiary.
This thesis addresses the overarching question of what the two business entities need to know about each other in terms of cultural characteristics and emerging differences in business practices (in terms of management/leadership) in order to improve the overall cooperation and working rela-tionship between the headquarter and its subsidiary. Thus, the following topics are emphasized with-in this thesis: tensions within the headquarter/subsidiary relationship, concise country profiles of Switzerland and Kenya including a cultural overview of both countries, cultural concepts including organizational culture, common leadership theories related to the situational leadership approach, and finally, an evaluation of the current status quo in the working relationship between the Swiss headquarter and the Kenyan subsidiary based on interviews.
The term start-up has become indispensable when new ideas are to be turned into business ventures. The number of start-ups is continuously increasing, but at the same time, many new start-ups are marked by failure. The successful path from start-up to a stable business model is to be explored in more detail in this thesis. The focus here is on the various success factors and how decisive they are.
At present, start-ups are mainly focusing on the area of digitalisation, not only triggered by the Covid19 pandemic but also by the high demand for digital products and services. In the past, start-ups founded in Silicon Valley/USA have been incredibly successful. Nevertheless, currently many other countries offer decisive advantages for start-ups and are therefore more attractive than the Silicon Valley. In Europe, Spain stands out with a rapidly growing start-up scene, primarily in the metropolises of Madrid and Barcelona.
This Master's thesis aims to empirically investigate the interrelationships of the necessary success factors in the start-up scene for the country of Spain. The focus of the study here is on the digitalisation industry. Qualitative content analysis is used for closer examination and is carried out through expert interviews. Qualitative research allows a much deeper insight into the interviewees' personal experiences and examines non-measurable factors. The subsequent evaluation is intended to present correlations and provide new insights. In summary, a list of recommendations is generated to provide future founders with suitable suggestions and advice right from the start.
This master thesis investigates leadership traits and how they can drive success within international organizations in the digital era. The basic principles of what defines a leader have undergone significant scrutiny throughout the past one hundred years, however, the digital revolution has created the most upset when considering the requirements for efficient leadership.
This paper utilizes a literature review to first determine how modern leadership theory developed and the implications of current research, followed by an empirical study designed to collect real-world data which represents how current leaders active in various industries understand their role as a leader and what skills they use to promote success within their organization.
Cross-examination of these sources indicates that the most effective leaders employ a combination of Transformational Leadership Theory and Emotional Intelligence-based leadership. The extent to which a leader must individualize their style is strongly contingent on the organizational culture, the individual employees, and the external environment. While traits such as communication, charisma, and trustworthiness are certainly strong indications of an efficient leader, agility and adaptability clearly stand out as the traits which are most required for highly effective leaders in the digital era.
This paper gives an insight into how cybersecurity is built inside and outside banks in Austria. The research was conducted based on information received from bank representatives in Austria as well as on literature, participation in various kinds of online conferences, and so on. The main objective of this paper was to investigate the cybersecurity execution scheme and to consider the possible impact of the cultural factor on cybersecurity execution. Due to a force majeure situation like coronavirus, the author was able to obtain little information from participants, but even this helped to draw satisfactory conclusions and make recommendations to banks. Thanks to the vast amount of literature and research, confirmation of the factor under study was found, confirming the relevance of the work and the potential for further research.
Companies worldwide and, therefore, companies from Vorarlberg face a common problem: the lack of skilled workers that led to the so-called “war for talents” in the last decades. This problem encouraged scientists to investigate the importance of many different monetary incentives and non-cash benefits to win this war for talents. This master’s thesis aims to examine if and how companies in Vorarlberg already use non-cash benefits. Furthermore, the most important benefits and their influence on the attractiveness of job advertisements are identified.
For this purpose, interviews with three HR managers from companies in Vorarlberg are carried out. Subsequently, in a quantitative survey, 21 different monetary incentives and non-cash benefits, intangible non-cash benefits, and corporate culture are evaluated by 316 participants. Furthermore, the participants ranked five different job advertisements to conceive results on the research questions.
The results clearly show that non-cash benefits are far more critical for future employees than classical monetary incentives. Although the number of international participants was lower than the number of Austrian and German participants (41 to 81 to 194), it is still obvious that independent of nationality, non-cash benefits can lead to a competitive advantage for companies in Vorarlberg. The interviews show that companies already work with such benefits in their daily business but do not strategically communicate on the topic.
To summarize, it can be concluded that a variety of non-cash benefits should be implemented within a company and also should be mentioned in job advertisements as they can help to attract more applicants not only from Austria but also from abroad and, therefore, help to win the war for talents.
Leadership, leader-follower relationship, and
subordinates’ behaviors during the Covid-19
pandemic
(2021)
In today’s world, companies feel the urge to disguise from competitors and to connect emotionally with consumers in order to foster a meaningful and long-lasting relationship. Simultaneously, stakeholders demand an increase of companies’ social responsibility. Cause-related marketing (CRM) is a marketing tool that addresses the change in societal values and the rising expectations from stakeholder groups. The increasing number of companies that choose to partner with a non-profit organization highlights that linking a charitable cause to the company's brand is an effective marketing tool. Authors illustrate that CRM, as a form of showing corporate social responsibility, will become even more important in the future. This master thesis examines the relationship between CRM, emotions, and culture. The research goal is to identify if CRM programs are effective in evoking emotions in consumers and if the cultural background of a consumer influences the evocation of certain emotions. The empirical findings outline that CRM programs are effective in evoking emotions. Other-focused emotions evoked by CRM programs are stronger expe-rienced by members of collectivistic countries than by members of individualistic countries. Likewise other-focused emotions evoked by CRM programs are stronger experienced by high interdependent selves than by low interdependent selves.
HRM Practices and Innovative Work Behavior: Employee Involvement and Job Auton-omy as influencing factors of Innovative Work Behavior
An organization´s capacity to innovate often resides within its employee´s innovative work behavior. Previous research suggested positive effects of employee involvement and job autonomy on innovative behavior. This research aims to analyze the impact of involvement- and autonomy-focused HRM practices (participation, information-sharing, work-scheduling autonomy, decision-making autonomy, and work-methods autonomy) on innovative work behavior. It is hypothesized that all five HRM practices mentioned above positively influence employees´ innovative work behavior. Therefore, a cross-sectional quantitative research design was chosen. Online questionnaire data from 376 employees in Austria was analyzed. Although all five HRM practices correlated with innovative work behavior, only work-methods autonomy had a statistically significant influence on the innovative work behavior of all employees. Thus, practitioners should include work-methods autonomy as critical HRM practice in a “high-innovation” HRM system to facilitate employees´ innovative work behavior.
In this work, the simulation possibilities of transient magnetic fields are investigated. For this purpose, an experimental setup is established to compare the simulation results with actual measurement data.
The experimental set-up consists of two coils, which are placed on two U-shaped iron cores. These cores are then brought together to form two air-gaps. These two gaps are used for measurement and the optional insertion of samples. The simulations are carried out with the finite element method (FEM) program ANSYS Maxwell 19R3.
In the first experiments, static simulations and measurements are compared to verify the validity of the available material data and the simulation techniques, especially the symmetry considerations, excitations of the coils, and boundary conditions. The static simulations show two main sources of uncertainty. The B-H curve of the core material used in the simulations and the air-gap distance uncertainty.
After validating the simulations with the static measurements, transient experiments are performed. In these experiments, the qualitative agreement of the simulation and measurement, as well as the characteristic rise times are compared. The experiments show a decisive influence of the considered loss mechanisms on the agreement of the simulation results with the measurements. Therefore, several simulations with different loss mechanisms are performed.
Finally, also the simulation capability including a material sample in the upper gap is investigated. Therefore, the conformity of the relative change of the measurement and the simulation is compared.
In the experiments a good simulation capability within a 5% error bar is seen. The main difficulty of this work represents the uncertainty due to the available material data. It is assumed, that with more accurate material data the error can be reduced significantly.
This paper analyses an electrical test tower of the OMCIRON electronics GmbH and evaluates whether a Predictive Maintenance (PdM) strategy can be implemented for the test towers. The company OMICRON electronics GmbH performs unit tests for its devices on test towers. Those tests consist of a multitude of subtests which all return a measurement value. Those results are tracked and stored in a database. The goal is to analyze the data of the test towers subtests and evaluate the possibility of implementing a predictive maintenance system in order to be able to predict the RUL and quantify the degradation of the test tower.
By assuming that the main degradation source are the relays of the test tower, a reliability modelling is performed which is the model-driven approach. The data-driven modelling process of the test tower consists of multiple steps. Firstly, the data is cleaned and compromised by removing redundances and optimizing for the best subtests where a subtest is rated as good if the trendability and monotonicity metric values are above a specific threshold. In a second step, the trend behaviours of the subtests are analyzed and ranked which illustrates that none of the subtests contained usable trend behaviour thus making an implementation of a PdM system impossible.
By using the ranking, the data-driven model is compared with the reliability model which shows that the assumption of the relays being the main error source is inaccurate.
An analysis of a possible anomaly detection model for a PdM is evaluated which shows that an anomaly detection is not possible for the test towers as well. The implementability of PdM for test towers and other OMICRON devices is discussed and followed up with proposals for future PdM implementations as well as additional analytical analyses that can be performed for the test towers.
The purpose of an energy model is to predict the energy consumption of a real system and to use this information to address challenges such as rising energy costs, emission reduction or variable energy availability. Industrial robots account for an important share of electrical energy consumption in production, which makes the creating of energy models for industrial robots desirable. Currently, energy modeling methods for industrial robots are often based on physical modeling methods. However, due to the increased availability of data and improved computing capabilities, data-driven modeling methods are also increasingly used in areas such as modeling and system identification of dynamic systems. This work investigates the use of current data-driven modeling methods for the creation of energy models focusing on the energy consumption of industrial robots.
For this purpose, a robotic system is excited with various trajectories to obtain meaningful data about the system behavior. This data is used to train different artificial neural network (ANN) structures, where the structures used can be categorized into (i) Long Short Term Memory Neural Network (LSTM) with manual feature engineering, where meaningful features are extracted using deeper insights into the system under consideration, and (ii) LSTM with Convolutional layers for automatic feature extraction. The results show that models with automatic feature extraction are competitive with those using manually extracted features. In addition to the performance comparison, the learned filter kernels were further investigated, whereby similarities between the manually and automatically extracted features could be observed. Finally, to determine the usefulness of the derived models, the best-performing model was selected for demonstrating its performance on a real use case.
With the digitalisation, and the increased connectivity between manufacturing systems emerging in this context, manufacturing is shifting towards decentralised, distributed concepts. Still, for manufacturing scenarios manual input or augmentation of data is required at system boundaries. Especially in distributed manufacturing environments, like Cloud Manufacturing (CMfg) systems, constant changes to the available manufacturing resources and products pose challenges for establishing connections between them. We propose a feature-oriented representation of concepts, especially from the manufacturing domain, which serves as the basis for (semi-) automatically linking, e.g., manufacturing resources and products. This linking methodologies, as well as knowledge inferred using it, is then used to support distributed manufacturing, especially in CMfg environments, and enhance product development. The concepts and methodologies are to be evaluated in a real world learning factory.
Background: Mobile health interventions are intended to support complex health care needs in chronic diseases digitally, but they are mainly targeted at general health improvement and neglect disease-specific requirements. Therefore, we designed TrackPAD, a smartphone app to support supervised exercise training in patients with peripheral arterial disease.
Objective: This pilot study aimed to evaluate changes in the 6-minute walking distance (meters) as a primary outcome measure. The secondary outcome measures included changes in physical activity and assessing the patients’ peripheral arterial disease–related quality of life.
Methods: This was a pilot two-arm, single-blinded, randomized controlled trial. Patients with symptomatic PAD (Fontaine stage IIa/b) and access to smartphones were eligible. Eligible participants were randomly assigned to the study, with the control group stratified by the distance covered in the 6-minute walking test using the TENALEA software. Participants randomized to the intervention group received usual care and the mobile intervention (TrackPAD) for the follow-up period of 3 months, whereas participants randomized to the control group received routine care only. TrackPAD records the frequency and duration of training sessions and pain levels using manual user input. Clinical outcome data were collected at the baseline and after 3 months via validated tools (the 6-minute walk test and self-reported quality of life). The usability and quality of the app were determined using the Mobile Application Rating Scale user version.
Results: The intervention group (n=19) increased their mean 6-minute walking distance (83 meters, SD 72.2), while the control group (n=20) decreased their mean distance after 3 months of follow-up (–38.8 meters, SD 53.7; P=.01). The peripheral arterial disease–related quality of life increased significantly in terms of “symptom perception” and “limitations in physical functioning.” Users’ feedback showed increased motivation and a changed attitude toward performing supervised exercise training.
Conclusions: Besides the rating providing a valuable support tool for the user group, the mobile intervention TrackPAD was linked to a change in prognosis-relevant outcome measures combined with enhanced coping with the disease. The influence of mobile interventions on long-term prognosis must be evaluated in the future.
With green cosmetics becoming widely used in Germany, this research would like to fill a research gap and investigate the impact of transatlantic transportation on the willingness of German customers to purchasing the product. With growing environmental awareness this information might be decisive for companies willing to expand internationally. They can take it into consideration when creating their international expansion strategy and deciding for the mode of entry.
Current research also explores the option of targeting the customers with marketing messages to share information about the low environmental impact of the transatlantic transport. It tests different marketing messages and analyses their impact on green purchase intention.
The phenomenon of the increase of numerous widespread and common diseases, ranging from simple dental problems to obesity, high blood pressure or diabetes, is a concern which can be observed in various aspects of the entire world. Reasons for this is a combination of an unhealthy diet and insufficient physical activity. Consequently, governments across the globe are seeing the need to change consumer behaviour by introducing plain packaging regulations. From an entrepreneurial point of view, this would result in financial losses as well as various limitations in product design, branding and differentiation. Therefore, an empirical study with 232 respondents was conducted, which revealed that the use of images on packaging activates emotions in customers within a few seconds. This master thesis examines possible correlations and differences between the importance of emotionally loaded product packaging and consumer behaviour at the point of sale. The persuasive effect of images on purchase decisions is based on personal consumer experiences and validated processing in the brain which trigger specific emotions. Modern companies are able to communicate company values through emotions by using images correctly. The results of the conducted survey enable Diezano to successfully implement the communication strategy in the event of the introduction of plain packaging regulations. By using mountain graphics, Diezano conveys values such as home, regional, refreshment, tasty, memories of childhood and nostalgia, which the brand aims to convey to the market. Based on the result of this master thesis, it is concluded that the picture superiority effect is mostly underestimated, yet it is an indispensable medium for emotional differentiation and thus a company’s success.
Marketing automation
(2021)
Packaging has important functions, such as the marketing function or protecting the product from spoilage. However, the supply in the supermarket must be viewed critically, as the majority of packaging is designed for single use. The question of how producers and retailers can increase customer acceptance of sustainable packaging in supermarkets has particular relevance in terms of the environmental impact of packaging waste. Although more and more customers are interested in the topic of sustainability, a gap between their attitude and behavior is apparent. This is addressed in more detail on the basis of two product categories. Expert interviews with international producers and retailers as well as a consumer survey allow the views of these three decision-makers to be taken into account. At the end, concrete recommendations for action are presented. These show that, among other things, information and transparency are essential in order to be able to influence consumers' purchasing decisions. In addition, the responsibility of all decision-makers is seen as the key to success.
The fact that services have emerged a driving force and the fastest growing sector in international trade attracts researchers to follow the changes taking place in the service industry. This study extends the scientific discussion on internationalization of service firms. Unlike previous research that examined factors that influence a single firm’s decision to internationalize, I acknowledge the heterogeneity of services, and based on the results obtained from secondary analysis of primary qualitative data sets, answer the main research question how internationalization motives differ between people-processing services, possession-processing services, and information-based services. This research goes beyond identification of variation in internationalization motives and analyses the service characteristics that might be responsible for the differences. In addition, I assess the key trends in the service sector and predict the possible future internationalization motives that are likely to emerge from the current trends.
Findings of this study reveal two major issues. First, it is evident that reasons for internationalization differ among hotel, retail firms and Higher education institutions representing people-processing services, possession-processing services, and information-based services respectively. Second, a few motives are common across sub-sectors, however the significance of the motives vary from sub-sector to sub-sector. I conclude that the differences in underlying structures of the respective service sub-sectors is the fundamental cause for the variation in internationalization motives among service sub-sectors. Other factors such as distinctive characteristics of service, firm’s competitive strategies, income elasticity of demand, and life-cycle stage of the service sub-sector also contribute to the differences in internationalization motives.
This paper also presents three different factors, which are likely to emerge as significant factors that influence service firm internationalization decision in future. (1) Company’s urge to be socially responsible and the need to contribute towards the environmental well-being (2) The need to sell regional products and services to neighbouring nations and respond to consumers’ demand for sustainable consumerism (3) Decision to penetrate foreign markets facilitated by the low risks and low cost of internationalization.
In this paper, we propose and simulate a new type of three-dimensional (3D) optical splitter based on multimode interference (MMI) for the wavelength of 1550 nm. The splitter was proposed on the square basis with the width of 20 x 20 µm2 using the IP-Dip polymer as a standard material for 3D laser lithography. We present the optical field distribution in the proposed MMI splitter and its integration possibility on optical fiber. The design is aimed to the possible fabrication process using the 3D laser lithography for forthcoming experiments.
In this paper, low-loss Y-branch splitters up to 128 splitting ratio are designed, simulated, and optimized by using 2D beam propagation method in OptiBPM tool by Optiwave. For an optical waveguide, a silica-on-silicon material platform is used. The splitters were designed as a planar structure for a telecommunication operating wavelength of 1.55 m. According to the minimum insertion loss and minimum non-uniformity, the optimum length for each Y-branch is determined. The influence of the pre-defined S-Bend waveguide shapes (Arc, Cosine, Sine) and of the waveguide core size reduction on the splitter performance has been also studied. The obtained simulation results of all designed splitters with different S-Bend shape waveguides together with the different waveguide core sizes are discussed and compared with each other.
Continuous monitoring of interactive exhibits in museums as part of a persuasive design approach
(2021)
Purpose: The purpose of this qualitative phenomenological study is to explore the of self-initiated expatriates prior to and during acculturation to life in a smaller periphery region such as Vorarlberg, Austria. By providing insights into their lived experience this research aims to fill in the gaps of missing information on motivators, success factors to adjustment, issues, and stressors, and more that SIEs experience when adjusting. Specifically, what items promote adjustment and what items hinder adjustment.
Findings: Developed a better understanding of how and what motivational factors lead to expatriation. Furthermore, that opportunities arise by chance. During acculturation, language factors (dialect), cultural differences act as stressors. While social support, and organizational support, learning of the language act as promoters of acculturation.
Further Research could be done including ethnicities, SIEs moving from developed to developing countries, adjustment in regions with dialect vs no dialect.
Key words: self-initiated expatriates, expatriation, acculturation, adjustment, promoting acculturation, hindering acculturation.
Whenever foreign activities turn out to be essential to ensure the company's goals and competitiveness, companies become international. New markets, new lucrative resources promise profitable growth. The new step beyond the national borders requires careful consideration based on the political conditions of the target market (e.g. stability of the political system, social peace, legal certainty, institutional barriers to market entry, attitude to direct investment). The legal framework, such as state funding, environmental protection laws, tax legislation, state requirements or bureaucratic regulations, appear to be at least as relevant too. However, SMEs often lack the capacity and/or courage to take this step. Political authorities at the European level and below are aware of this problem. Numerous studies show that internationalisation is not only necessary to improve competitiveness, but greatly promote innovation, e.g. within international collaborations, it is important to get the authorities to treat these issues with special attention. Governmental promotion is supposed to work in terms of establishing regional balance and supporting socially relevant topics and research. Nevertheless, despite the willingness to support SMEs in their cross-border projects, billions of released Euros are lying around and have not been used. It seems reasonable to assume money is not easy to come by. Enormous bureaucratic hurdles are on everyone's lips. But is that the only reason? Are the people sufficiently informed to be able to take advantage of the numerous financing opportunities? Or is there even more behind the invisible hurdle at first glance? To ascertain this circumstance more precisely, an in-depth analysis to answer the research question ‘what can the institutions do better to make it easier for SMEs to access funding?’ is required.
The research activity described in this master thesis focus on global leadership in team sport. Football head coaches working or who have worked in the globalised Big Five leagues of England, France, Germany, Spain and Italy are investigated. These leagues are host to players, staff, executives, fandoms and head coaches from around the globe. Sport in general is posed as a valid platform to investigate global leadership. Elite and globalised clubs in association football are further posed the archetype of global sport. Head coaches at the helm of the on-field and off-field teams are hypothesised as global leaders, due to their squad, staff and networks of global nature and the span of their influence on individuals around the globe.
It is proposed that investigations of the leadership in this setting can usefully contribute to insights on global leadership. The research activity follow an exploratory purpose resulting from a gap found in the literature review. The research design framework is a first sequential loop of Ground Theory methodology with the aim to identify useful hypotheses for future theoretical sampling. Secondary data was gathered and analysed qualitatively. The data stems from the public domain and statements from interviews, commentaries, biographies, and conferences on or by the head coaches. The theoretical framework of the presented re-search covers the personal traits and attributes of the investigated individuals.
Findings both overlap and contrast with findings from other global leadership research activities. The differences were identified in properties of the global sport business such as constant public attention. Based on the findings from the purposive sampling and acknowledging applicable limitations on the findings, hypotheses for theoretical sampling are proposed. Theoretical sampling is the next step in the workflow of the Grounded Theory methodology used for this study.
In the regime of incentive-based autonomous demand response, time dependent prices are typically used to serve as signals from a system operator to consumers. However, this approach has been shown to be problematic from various perspectives. We clarify these shortcomings in a geometric way and thereby motivate the use of power signals instead of price signals. The main contribution of this paper consists of demonstrating in a standard setting that power tracking signals can control flexibilities more efficiently than real-time price signals. For comparison by simulation, German renewable energy production and German standard load profiles are used for daily production and demand profiles, respectively. As for flexibility, an energy storage system with realistic efficiencies is considered. Most critically, the new approach is able to induce consumptions on the demand side that real-time pricing is unable to induce. Moreover, the pricing approach is outperformed with regards to imbalance energy, peak consumption, storage variation, and storage losses without the need for additional communication or computation efforts. It is further shown that the advantages of the optimal power tracking approach compared to the pricing approach increase with the extent of the flexibility. The results indicate that autonomous flexibility control by optimal power tracking is able to integrate renewable energy production efficiently, has additional benefits, and the potential for enhancements. The latter include data uncertainties, systems of flexibilities, and economic implementation.
One goal of the project described in this paper is to create learning algorithms for machines and robots that lack a precise virtual controller for correct simulations. Using a digital twin approach, the developed mixed reality application aims for an overlay of a virtual robot model with the real world counterpart using Microsoft HoloLens 2 smart glasses. The application should help users to have an inside look into the results of the learning algorithm and therefore supervise and improve those results. The main focus of this paper is the visual representation of the digital twin on the smart glasses. One of the challenges is the level of abstraction and specific use of shaders (program code defining material attributes) to help the user differentiating between virtual and real objects. Therefore different presentation methods are described and evaluated. Study results with 48 persons show that the most abstract representation (wireframe) scores lowest, whereas a half-transparent model works best.
Mobility choices - an instrument for precise automatized travel behavior detection & analysis
(2021)
This study deals with the energy situation in Ny-Ålesund, an Arctic research station on the archipelago Svalbard, and aims at analysing the technical feasability of a transition to renewable energies by taking into consideration both the environmental and climatic impediments.
The analysis is based on a 27 year long collection of authentic meteorological data with all its strong fluctuations, seasonal as well as yearly. Great emphasis was put on the discussion of tried-and-tested renewable technologies that were compared to a new wind-based energy device that has yet to be tested for its reliability in the harsh environment of notably the Arctic winter. Meticulous calculations lead to the result that bifacial solar modules are an efficient means even in months when the sun stands low and their combination with wind-based devices prove to generate a maximum output. Geothermal energy seems to be promising in the region, but could not be evaluated due to a crucial lack of relevant data.
The study comes to the conclusion that the research station of Ny-Ålesund could well rely on a combination of renewable energy devices to cover its energy load, but needs to keep a back-up system of diesel run generators to bridge short periods of possible dysfunctions or standstills due to meteorological circumstances. Battery storage could only contribute to solve the problem of an unfortunate interruption of the energy supply, but it cannot serve as the entire back-up system since, at present, the need would go beyond all possible dimensions.
Recently the use of microRNAs (miRNAs) as biomarkers for a multitude of diseases has gained substantial significance for clinical as well as point-of-care diagnostics. Amongst other challenges, however, it holds the central requirement that the concentration of a given miRNA must be evaluated within the context of other factors in order to unambiguously diagnose one specific disease. In terms of the development of diagnostic methods and devices, this implies an inevitable demand for multiplexing in order to be able to gauge the abundance of several components of interest in a patient’s sample in parallel. In this study, we design and implement different multiplexed versions of our electrochemical microfluidic biosensor by dividing its channel into subsections, creating four novel chip designs for the amplification-free and simultaneous quantification of up to eight miRNAs on the CRISPR-Biosensor X (‘X’ highlighting the multiplexing aspect of the device). We then use a one-step model assay followed by amperometric readout in combination with a 2-minute-stop-flow-protocol to explore the fluidic and mechanical characteristics and limitations of the different versions of the device. The sensor showing the best performance, is subsequently used for the Cas13a-powered proof-of-concept measurement of two miRNAs (miRNA-19b and miRNA-20a) from the miRNA-17∼92 cluster, which is dysregulated in the blood of pediatric medulloblastoma patients. Quantification of the latter, alongside simultaneous negative control measurements are accomplished on the same device. We thereby confirm the applicability of our platform to the challenge of amplification-free, parallel detection of multiple nucleic acids.
In this work, we present a significant step toward in vivo ophthalmic optical coherence tomography and angiography on a photonic integrated chip. The diffraction gratings used in spectral-domain optical coherence tomography can be replaced by photonic integrated circuits comprising an arrayed waveguide grating. Two arrayed waveguide grating designs with 256 channels were tested, which enabled the first chip-based optical coherence tomography and angiography in vivo three-dimensional human retinal measurements. Design 1 supports a bandwidth of 22 nm, with which a sensitivity of up to 91 dB (830 µW) and an axial resolution of 10.7 µm was measured. Design 2 supports a bandwidth of 48 nm, with which a sensitivity of 90 dB (480 µW) and an axial resolution of 6.5 µm was measured. The silicon nitride-based integrated optical waveguides were fabricated with a fully CMOS-compatible process, which allows their monolithic co-integration on top of an optoelectronic silicon chip. As a benchmark for chip-based optical coherence tomography, tomograms generated by a commercially available clinical spectral-domain optical coherence tomography system were compared to those acquired with on-chip gratings. The similarities in the tomograms demonstrate the significant clinical potential for further integration of optical coherence tomography on a chip system.
With Cloud Computing and multi-core CPUs parallel computing resources are becoming more and more affordable and commonly available. Parallel programming should as well be easily accessible for everyone. Unfortunately, existing frameworks and systems are powerful but often very complex to use for anyone who lacks the knowledge about underlying concepts. This paper introduces a software framework and execution environment whose objective is to provide a system which should be easily usable for everyone who could benefit from parallel computing. Some real-world examples are presented with an explanation of all the steps that are necessary for computing in a parallel and distributed manner.
We present a new concept of 3D polymer-based 1 × 4 beam splitter for wavelength splitting around 1550 nm. The beam splitter consists of IP-Dip polymer as a core and polydimethylsiloxane (PDMS) Sylgard 184 as a cladding. The splitter was designed and simulated with two different photonics tools and the results show high splitting ratio for single-mode and multi-mode operation with low losses. Based on the simulations, a 3D beam splitter was designed and realized using direct laser writing (DLW) process with adaptation to coupling to standard single-mode fiber. With respect to the technological limits, the multi-mode splitter having core of (4 × 4) μm 2 was designed and fabricated together with supporting stable mechanical construction. Splitting properties were investigated by intensity monitoring of splitter outputs using optical microscopy and near-field scanning optical microscopy. In the development phase, the optical performance of fabricated beam splitter was examined by splitting of short visible wavelengths using red light emitting diode. Finally, the splitting of 1550 nm laser light was studied in detail by near-field measurements and compared with the simulated results. The nearly single-mode operation was observed and the shape of propagating mode and mode field diameter was well recognized.