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The Role of Cultural Intelligence on the Choice of a Cross-Cultural Conflict Management Style and on Cooperation in a Public Goods Experiment
No full textEmpirical studies have shown that CQ predicts cross-cultural task performance, negotiation tactics, and expatriate adjustment. However, no study has examined if and how CQ predicts conflict management and cooperation in an intercultural working context.
The first study was conducted to develop a situational judgment test which measures five cross-cultural conflict management styles (integrating, dominating, avoiding, compromising, and obliging) (Rahim & Bonoma, 1979). The resulting instrument consisted of three scenarios with five answer options (corresponding to the five styles). The second study examined if cognitive, motivational and metacognitive CQ predict support for five conflict management styles. It was also investigated if the salience of national or global identity can moderate these relationships. Participants first completed questionnaires measuring the three CQ dimensions and some control variables. Then either their national or their global identity was made salient. Cognitive CQ was positively associated with the avoiding style, motivational CQ was positively associated with the obliging style, and metacognitive CQ was negatively associated with the dominating style. In addition, the salient national and global identities moderated some of these relationships.
The goal of the third study was to investigate if CQ predicts cooperation in a repeated public goods game with culturally diverse groups of participants. Participants first completed an online questionnaire measuring the level of their cultural intelligence. Then they played in the lab ten periods of the public goods game. The results showed that only motivational CQ is positively associated with cooperation. In addition, global identity salience moderated the relationship between behavioral CQ and cooperation. These findings have implications for a more effective assignment of people with specific CQ characteristics to tasks requiring cooperative actions
Generalized Simultaneous Localization and Mapping (SLAM) on Graphs with Multimodal Probabilities and Hyperedges
No full textSimultaneous Localization and Mapping (SLAM) is one of the cornerstones of robotics research. Any mobile robot which is to operate in a previously unknown area requires a method for estimating both a model of its new surrounding and its location within it. Even stationary robots that may have to process previously unknown objects require a method to model these objects as they are detected. SLAM methods offer solutions for these situations, utilizing varying sensors, robot models, and estimation techniques.
This thesis focuses on Graph-based SLAM methods, where sensor observations are related with spatial constraints in a network fashion. Numerical optimization methods are used to estimate the most likely global configuration of observations, which, when merged, represents the model of the environment or object in question. However, the original graph topology and sensor observations are kept intact and are reusable for further mapping operations.
The thesis consists of two main parts. First, several contributions to traditional Graph-based SLAM research are discussed. Novel uncertainty estimation techniques for 2D and 3D spectral registration methods are described that allow the use of such methods in Graph-based SLAM. Spectral registration methods are especially robust to noise and their computational requirements only depend on the resolution of the data, not its structure. Additionally, novel approaches to multi-robot Graph-based SLAM under communication constraints are described, including a formal description of the underlying graph structure and techniques to optimize the use of available bandwidth.
Second, novel contributions in the very exciting field of robust optimization techniques for Graph-based SLAM are shown and collected in the description of the Generalized Graph SLAM framework. Specifically, the two major sources of errors in traditional Graph-based SLAM are addressed: Multiple local optima in the registration cost function (local ambiguity) that can impact the performance of traditional methods severely are represented in the Generalized Graph SLAM framework as multimodal probability distributions within the spatial constraints. The second major source of errors lies in place recognition methods, which is needed to improve the map by relating current sensor observations to much older ones. Significant work has been done to eliminate false positives, usually at the cost of false negatives. When a repetitive environment gives rise to multiple independent places in the map that fit the current sensor observation (global ambiguity), traditional methods would either disregard such ambiguous results if they can be detected or fatally diverge. In order to take full advantage of even such globally ambiguous cases, they are represented as hyperedges in the Generalized Graph SLAM framework. Multiple estimation methods are described that are applicable to these extended graph structures. Additionally, a method to generate multimodal registration results is presented.
All contributions are further substantiated with extensive experimental results, both using synthetic and real world data sets. Synthetic data sets are used for systematic analysis of the involved parameters and comparison with ground truth. Results on real world data sets show the applicability and effectiveness of the respective methods in realistic scenarios
Indonesia-EU Trade Relations : A Case Study of International Trade between South and North
No full textThis case study is aimed at describing and explaining reciprocal trade relations between Indonesia representing the South and the EU representing the North. This study uses both descriptive and explanatory case studies. In the descriptive study, this study analyzes the trade volume and pattern of two political entities. In this part, this study also calculates and analyzes the RCA index and export performances. Results of the descriptive study have been used in selecting six cases. In the explanatory study, trade incentives and barriers that increase and restrict exports, respectively, in either direction are investigated. This involves the collection and analysis of firm level primary data and secondary data. In analyzing collected data, this study uses one primary data and four secondary data.
In the case of Indonesia’s exports to the EU, the application of different methods of analysis has identified simple entry procedures, low technical barriers, good logistics, higher product quality, larger market size, endowment factors, GDP, and past colonial relations as trade incentives. Data analysis has also suggested that technical impediments, bad logistics, distance, high competition, production capacity, tariff barriers, and market entry procedures are barriers to export volume. In the case of the EU exports to Indonesia, data analysis has identified technology superiority, low tariffs, innovation, larger market size, distributor/local partner, patent ownership, GDP, and product quality as trade incentives of such exports. Data analysis has also revealed that higher tariffs, corruption, distance, absence of a unified patent system, increasing cost of production, and market entry procedures are barriers to the EU exports to Indonesia.
Hence, Indonesia and the EU should better formulate their future bilateral trade policy. Bilateral trade partnership should contain promotion and elimination of regulatory trade incentives and barriers in order to create trade
Schubert slices in the combinatorial geometry of flag domains
No full textFlag domains are open orbits of real semisimple Lie groups in flag manifolds of their complexifications. Certain group theoretically defined compact complex submanifolds, which are regarded as cycles are of basic importance for their complex geometric and representation theoretic properties. It is known that there are optimal Schubert varieties which intersect the cycles transversally in finitely many points and in particular determine them in homology. Here we give a precise description of these Schubert varieties in terms of certain subsets of the Weyl group and compute their total number for all the real forms of SL(n,C). Furthermore, we give an explicit description of the points of intersection in terms of flags and their number
Enabling Networked Visible Light Communications
No full textThis thesis focuses on optical wireless communications (OWC), where optical beams are used to transmit information in free space, with wavelengths ranging from infrared (IR) to ultraviolet (UV) including the visible light spectrum. We are particularly interested in visible light communication (VLC) that uses standard o-the-shelf visible light emitting diode (LED) luminaires to transmit broadband data streams. New technical solutions are developed to cope with the increasing demand for wireless data. The well utilised radio frequency (RF) spectrum which is primarily used to provide wireless services is confronted with the problem of a severe spectrum shortage, also referred to as 'spectrum crunch'. A potential solution to this problem is OWC that targets an entirely different part of the electromagnetic spectrum, the infrared and visible light spectrum. For example, indoor OWC systems based on LEDs as light sources and orthogonal frequency division multiplexing (OFDM) as a modulation technique have attracted substantial research interest. In VLC, the white LEDs providing lighting can also be modulated to achieve high-speed wireless data transmission. The combination of lighting design and light communication allows the VLC system to coexist and benefit from the lighting setup present in many indoor environments (e.g. offices, homes, public places). The high signal-to-noise ratio (SNR) stemming from an illuminated room can make VLC very attractive to provide the indoor wireless link instead of using an outdoor radio base station to send the radio frequency signal through multiple walls. Especially with the increasing usage of data over mobile phones and other wireless devices, this technology can be a powerful alternative to complement existing RF wireless systems.
In this thesis, key challenges of optical wireless systems have been investigated. We focus on the transmission opportunities given by the current illumination scenario where a single coordinated optical source or multiple optical access points (APs) are installed in the room. First we evaluate the performance of such a VLC system in terms of average area spectral efficiency (ASE). The ASE is derived for optical wireless in a similar way to RF cellular networks and verified through Monte Carlo simulations. More than three orders of magnitude improvement in ASE is achieved by employing a VLC system indoors as compared to state-of-the-art wireless radio systems. While wireless femtocell base stations are a suitable solution for increasing indoor coverage in areas with high user density, VLC has the potential to deliver much higher data rates. This study compares the ASE of both technologies in a real world scenario and demonstrates the great potential of VLC to act as a powerful complementary technology to femtocells indoors. Moreover by allowing different light sources in a room to coexist and exploit the LED light radiation characteristics as well as the particular characteristics of the optical detectors, the improvement in ASE for VLC can be enhanced further. The lighting equipment in a VLC system should also full the function of wireless data transmission. Therefore, a close investigation of the best placement of the lighting system in a room for illumination and communication performance is important for the end-user experience. In this thesis we investigate the transmitter LED arrays design and placement in a room in order to achieve the required lighting distribution and reliable data transmission at the same time. The design of the LED lighting system and placement in the room for VLC is formulated as a constrained optimization problem and applied to a room of 2.5m x 5m x 3m dimension where lighting is provided by two square LED arrays. Based on numerical simulations it is demonstrated that the system performance in terms of average ASE is degraded when fulfilling the lighting conditions compared with the situation where the VLC system targets only the maximization of the communication performance evaluated also in terms of average ASE. Furthermore, a search is performed for the optimal feld of view (FOV) of the detector that maximizes the communication performance and also guarantees the minimum illumination in the room. Another challenge related to the implementation of high-speed VLC is light dimming. This allows an LED system to save energy by controlling the brightness of LEDs. A dimming approach based on amplitude reduction is proposed for VLC systems employing asymmetrically clipped optical orthogonal frequency division multiplexing (ACO-OFDM) as a modulation scheme. In addition, the impact of the induced distortions due to the nonlinear behavior of the LED as a light source is included in the analysis. The performance of an ACO-OFDM system is investigated in a practical room scenario where various lighting requirements (e.g. brightness levels) are viable. The DC optical power/bias point level must be changed adaptively to maximize the useful dimming range and to maintain a good SNR. By properly selecting the DC optical power and the useful optical signal power, an optimum SNR can be achieved. It is also shown that signal power dependence of induced nonlinear effects clearly limits the maximum achievable data rates.
Finally, an air-interface for a cellular optical wireless communication network is developed that is capable of serving multiple users in a point-to-multipoint as well as multipoint-to-point fashion. Physical layer techniques based on OFDM are developed to enable data rates in exceed of 100 Mbps. OFDM is chosen as a modulation technique due to the ability to support high data rates by using high order multi-level quadrature amplitude modulation (M-QAM) without the need of complex channel equalizers. Moreover, OFDM presents an inherent robustness against multipath eects, due to the use of a cyclic prefix (CP) attached to the transmitted OFDM symbols. As a result intersymbol interference (ISI) due to multipath dispersion effects is completely avoided. Multipath dispersion is a significant problem in indoor applications especially at high data rates. Particularly in a diffuse link this problem leads to serious ISI and degrades performance severely.
This thesis describes also the digital signal processing algorithms of a complete orthogonal frequency division multiple access (OFDMA) system including forward error correction (FEC), subcarrier allocation, inverse fast Fourier transform (IFFT) operation, synchronization, channel estimation and equalization. Bit error ratio (BER) measurements of the optical wireless link incorporating the Xilinx field programmable gate array (FPGA) board, the analog-to-digital converter (ADC)/digital-to-analog converter (DAC) platform developed by Funkwerk Avionics and the optical tranceiver modules produced by Heinrich Hertz Institute are presented to evaluate the performance of the developed system. Moreover, basic proof-of-concept demonstrations involving 100 Mbps transmission from an access point to two spatially separated users are successfully conducted. For this purpose two separate video streams were transmitted to the two users
Analyte-Responsive Macrocyclic Host-Fluorophore Systems For Monitoring Biological Processes
No full textThis thesis describes the application of systems composed of a fluorophore and macrocyclic host as a sensitive and versatile analytical method to study biological processes, in particular, transport through the lipid-bilayer biomembrane and reactions catalyzed by proteases.
While it is acknowledged that only small and hydrophobic molecules can pass through the bilayer directly and while the importance of channel proteins for selective uptake is well recognized, methods to directly and sensitively monitor these membrane transport processes remain in high demand.
In the first part of the thesis, I introduce an in vitro fluorescence-based biomembrane assay—the supramolecular tandem membrane assay—based on host–guest, macrocycle–fluorophore reporter pairs encapsulated inside liposomes. Three features make this novel method unique. First, the tandem membrane assay allows label-free continuous monitoring of translocation through the lipid bilayer or through channel-proteins, which was previously not possible. Second, the assay is economic and versatile, i.e., applicable to both, diffusion through the membrane and translocation through channel proteins of different classes of translocating biomolecules. Third, the assay allows direct access to kinetic information of analyte permeation on microsecond-to-hours time scales. As a first application of the tandem membrane assay, we applied it to the unsolved biological question, whether cationic antimicrobial peptides, in particular, protamine, can enter into the cell through an outer membrane channel protein. For the first time, conclusive experimental evidence has been provided that such antimicrobial peptides can indeed enter through bacterial channels.
Protease assays for natural or unlabelled synthetic substrates are very much sought after, but the few assays that have been developed are limited to the general detection of protease activity. In the second part of this thesis, I present the label-free fluorescence-based protease assay—the supramolecular tandem protease assay. This newly developed label-free method overcomes the use of covalently attached fluorescent labels in peptides by, again, employing macrocycle–fluorophore reporter pairs. The beauty of our sensitive and versatile protease assay lies not only in being able to (i) monitor protease activity in real-time, but also in its utility to (ii) profile the substrate specificity of a protease, (iii) to sense enzyme substrate stereoselectivity, and (iv) in its utility for rapid and convenient screening of inhibitors and protease–resistant peptides. Additionally, the tandem protease assay allows stepwise proteolytic degradation of an entire peptide to be easily followed as sequential changes of the fluorescence response, which led us to the idea of peptide fingerprinting through unique fluorescence profiles
Neurophysiological Correlates of Tactile Perception: Age-Related Differences in Tactile Perception and Tactile Learning
No full textWith age, one's tactile perception declines. But tactile expertise and short-term tactile learning can induce cortical plasticity and improve tactile perception. Thus, tactile learning might contribute to the maintenance of tactile perception. Open questions were how age and expertise influence tactile perception and learning in middle-aged adults and how the respective electrophysiological correlates are shaped by age, expertise, and learning.
We investigated tactile discrimination and event-related potentials as markers of somatosensory and cognitive processing. Participants were of different age groups [young (18-25 years), early middle-aged (35-45 years), and late middle-aged adults (55-65 years)] and expertise levels [non-experts (service employees) and experts (precision mechanics)]. Learning was induced by repetitive tactile stimulation.
Late middle-aged performed worse than young and early middle-aged adults. Somatosensory excitability increased and processing speed reduced with age. P300 topography suggested attempted compensation and reduced availability of attentional resources in late middle-aged non-experts. Experts outperformed non-experts, revealed greater somatosensory excitability, and needed less attentional resources, as compared to non-experts. This suggested that comparable electrophysiological changes induced by age and expertise have different underlying mechanisms.
Experts improved more than non-experts from the intervention, indicating meta-plasticity. Lower baseline performance was associated with higher learning. Intervention-related changes in P300 indicated that younger adults processed tactile stimuli faster, while older adults became better able to cognitively evaluate the stimuli. Experts established more specific brain activation, with a strong parietal-to-frontal gradient, pointing to more automated processing.
Results further the understanding of tactile perception in middle-aged adults and opened up new research questions
Simulation of the Laptev Sea shelf dynamics with focus on the Lena Delta region
No full textThe polar shelf zones are highly dynamic and diverse systems. They form a border between warm and fresh water of continental drain and the cold currents of the northern seas. The Lena River is one of the largest rivers in the Arctic, with the largest delta. The south-eastern part of the Laptev Sea, which includes the Lena Delta region, is the place where substantial changes in ocean circulation and ecosystem may happen in changing climate. Exploring processes there, which may serve as an indicator of climate change, acquire a special importance.
The Lena freshwater plume propagation dominates many aspects of dynamics in the Laptev Sea shelf. However, the direct measurements are by far insufficient, calling for a modeling approach which would enable one to estimate the impact of different factors on the circulation dynamics and would lay the foundation for further ecosystem modeling. The complexity of the region’s geometry and insufficient data make modeling of ocean circulation in the Lena Delta vicinity a challenging technical task not solved in the necessary detail previously. The quantitative effect of various factors (tides, winds, hear exchange with the atmosphere) on the freshwater plume propagation also has not been fully explored.
The main goal of this thesis is the analysis of the Lena River freshwater plume dynamics in the summer season on the basis of a full baroclinic numerical model of the Laptev Sea shelf with focus on the Lena Delta region. The setup is based on FVCOM (The Unstructured Grid Finite Volume Coastal/Community Ocean Model).
The thesis contains a detailed description of the model setup, including the generation of an unstructured mesh, analysis of barotropic and baroclinic dynamics in the region of interest, the description of new approaches for the model elaboration and visualization of simulation results and a comparison of the impact of different atmospheric forcing products on the simulated dynamics. Special attention is paid to the Lena River hydrology regime in the basin outlet, which is taken into account in simulations.
Since tides are responsible for a considerable fraction of mixing over the shallow shelf of the Laptev Sea, the first step consisted in accurate modeling of barotropic tides in the Lena Delta region of the Laptev Sea. This demanded using accurate topography data and the design of optimized open boundary conditions that would provide the best agreement with observations. The simulated tidal maps for principal semidiurnal constituents, which are the most important in the considered area, showed an improved agreement with observations as compared to other modeling efforts. Important information about barotropic currents, evolution of energy fluxes in the region and residual circulation, which affects sediment and nutrients transport, was obtained in this work.
The next important step toward more realistic simulations was taking into account the Lena River hydrology. This step required substantial preliminary work on compiling and analyzing respective Lena River characteristics in the basin outlet area. The anomaly in surface water temperature was found to exist at the most downstream location in the summer season. Its description and basic analysis is presented. To sort the problem of anomaly out, the observational data in the scope of hydrology and morphology for the Lena River delta and main channel area, including data on permafrost conditions under the river channel, were considered.
The third step was full baroclinic simulations with focus on the Lena River freshwater plume dynamics in the summer season. The role of tides, winds and thermohaline forcing in shaping the plume dynamics was explored by applying different sources of atmospheric forcing and switching on/off tidal dynamics. In addition, the roles of local bathymetry and techniques of freshwater distribution were assessed. A detailed comparison with the available observational data was also performed showing a good agreement. It was found that the surface salinity distribution is most sensitive to winds, with the implication that the ability of model to predict it relies on the availability of high-quality wind forcing data. Tidal mixing and residual transport are important, but only locally, whereas heat exchange with the atmosphere influences the water mass properties, but has only a weak impact on dynamics.
This understanding together with the proof that the model simulations agree well with the observational data are the main results of this thesis. They demonstrate that the model can serve as a platform for future ecosystem modeling in the Lena Delta region
Crustal and lithosphere dynamics of the Southern Pacific and the West Antarctic margin
No full textCurrently, there is a broad interest in the development of paleotopographic models for the West Antarctic margin, which are essential for robust simulations of paleoclimate scenarios. Recent work has shown that large uncertainties in past topography reconstructions have led to false conclusions about the growth and the extend of Antarctica's ice sheet. The evolution of the polar ice sheets is one of the driving factors of global climate change. Improvements on paleotopographic models are therefore fundamental for a better understanding of the climate in the past.
In this thesis, the author acquired and analyzed a new geomagnetic dataset off the West Antarctic margin, refined the South Pacific plate-tectonic reconstruction, and for the first time estimated the deformation of Antarctica's passive continental margins. The new data constrain the age of the rifted oceanic margin of West Antarctica and indicate that initial seafloor formation propagated westward from the Bellingshausen sector between ~89 and 84 Myr. In the Ross Sea area little continental deformation (<90 km) is observed prior to the breakup of Gondwana. However, further east the independent motion of the Bellingshausen microplate over a period of 22 Myr extended the continental margin by 106–304 km. Subsequent intraplate magmatism further altered the lithosphere. The rifting phase along the Pacific margin of Antarctica was comparatively short. Elsewhere in Antarctica rifting lasted much longer and was slow enough to allow for 300–400 km of margin extension.
The author further determined the total sediment thickness from seismic data, calculated cross-regional total sediment thickness grids of the Southern Pacific, and derived the sediment unloaded basement topography. The data indicate that sediment thickness along the Pacific margin of Antarctica is about 3–4 km larger than previously assumed and that the sediment volume has been underestimated. Hence, the re-evaluation of erosion rates and West Antarctica's topography are eminent to improve our understanding of Antarctica's glaciation history.
Grids of sediment corrected basement depth and residual basement depth of the South Pacific were derived from the sediment thickness and then compared to the present-day state of dynamic topography models. The mean residual basement depth of the Antarctic plate is about 300 m higher than that of the Pacific plate. The observations support the existence of a persistent mantle plume beneath the Ross Sea and the Balleny Islands hotspot area. However, dynamic topography disagrees with the presented residual basement depth of the South Pacific. Consequently, predictions of the South Pacific paleotopography remain speculative until more accurate dynamic topography models, which explain the anomalous basement depth become available
A Framework for Defining Declarative Languages
No full textDeclarative languages are an important family of formalisms used for formal knowledge representation in computer science. Examples include logics, type theories, set theories, specification languages and ontology languages. Despite the vast variety of declarative languages, they share a common structure: A possibly infinite collection of theories, which are sets of declarations, and a set of well-formed expressions over each theory.
This PhD thesis contributes to the design of declarative logical frameworks that balances the trade-off between abstract and concrete representations of declarative languages. In particular, we identify a new feature that can be added to a declarative framework as a language primitive: declaration patterns. The main idea behind this feature is to capture the common structure of the theories of declarative languages.
More specifically, we reify declaration patterns as a language primitive for declarative logical frameworks and use them to characterize the legal declarations of non-logical symbols by specifying their syntactic shape. Then, we introduce a notion of pattern-based translation, which maps legal theories of one declarative language to legal theories of the other language.
We introduce these novel notions in a calculus-based meta-framework for defining declarative languages and translations between them. Our meta-framework is independent of the underlying declarative logical framework and can be instantiated with specific logical frameworks like LF. In particular we develop a new declarative logical framework LFS (LF with sequences) that supports sequences and dependent function spaces that take sequence arguments, which we need for writing down the declaration patterns of most declarative languages.
We apply and evaluate our pattern-based approach in an atlas of declarative languages, which includes various logics ranging from traditional first-order logic to more complex languages such as polymorphic higher order logic