1,790 research outputs found
The impact of cultural intelligence on communication effectiveness, job satisfaction and anxiety for Chinese host country managers working for foreign multinationals
Cultural intelligence (CQ) is an important construct attracting growing attention in academic literature and describing cross-cultural competencies. To date, researchers have only partially tested the relationship between CQ and its dependent variables, such as performance. In this study, the relationship between CQ and communication effectiveness and job satisfaction is measured in a sample of 225 Chinese managers working for foreign multinational enterprises in China. The results show that CQ plays an important role in reducing anxiety and influencing both communication effectiveness and job satisfaction positively. Another outcome is the unexpected influence of anxiety on job satisfaction but not on communication effectiveness. These findings contribute to the development of theory with regard to the CQ construct
Light-induced dipolar spectroscopy - A quantitative comparison between LiDEER and LaserIMD
Nanometric distance measurements with EPR spectroscopy yield crucial
information on the structure and interactions of macromolecules in complex
systems. The range of suitable spin labels for such measurements was recently
expanded with a new class of light-inducible labels: the triplet state of
porphyrins. Importantly, accurate distance measurements between a triplet label
and a nitroxide have been reported with two distinct light-induced spectroscopy
techniques, (light-induced) triplet-nitroxide DEER (LiDEER) and laser-induced
magnetic dipole spectroscopy (LaserIMD). In this work, we set out to
quantitatively compare the two techniques under equivalent conditions at Q
band. Since we find that LiDEER using a rectangular pump pulse does not reach
the high modulation depth that can be achieved with LaserIMD, we further
explore the possibility of improving the LiDEER experiment with chirp inversion
pulses. LiDEER employing a broadband pump pulse results in a drastic
improvement of the modulation depth. The relative performance of chirp LiDEER
and Laser-IMD in terms of modulation-to-noise ratio is found to depend on the
dipolar evolution time: While LaserIMD yields higher modulation-to-noise ratios
than LiDEER at short dipolar evolution times ({\tau}=2 {\mu}s), the high phase
memory time of the triplet spins causes the situation to revert at {\tau}=6
{\mu}s.Comment: 9 pages, 4 figures and supporting information (18 pages, 11 figures
Bogoliubov theory for atom scattering into separate regions
We review the Bogoliubov theory in the context of recent experiments, where
atoms are scattered from a Bose-Einstein Condensate into two well-separated
regions. We find the full dynamics of the pair-production process, calculate
the first and second order correlation functions and show that the system is
ideally number-squeezed. We calculate the Fisher information to show how the
entanglement between the atoms from the two regions changes in time. We also
provide a simple expression for the lower bound of the useful entanglement in
the system in terms of the average number of scattered atoms and the number of
modes they occupy. We then apply our theory to a recent "twin-beam" experiment
[R. B\"ucker {\it et al.}, Nat. Phys. {\bf 7}, 608 (2011)]. The only numerical
step of our semi-analytical description can be easily solved and does not
require implementation of any stochastic methods.Comment: 11 pages, 6 figure
Statistischer Qualitätsvergleich von Kreditausfallprognosen
Die statistische Qualität von Kreditausfallprognosen läßt sich auf unterschiedliche Art und Weise messen und vergleichen. Die vorliegende Arbeit faßt die in der Literatur gemachten Vorschläge zusammen und diskutiert deren Eignung für das Alltagsgeschäft von Kreditausfallprognosen im Privatkundenbereich. Es zeigt sich, daß nicht alle Qualitätskriterien hier sinnvoll anzuwenden sind. Insbesondere scheinen die etwa in der Meteorologie beliebten Brier Scores und verwandte Kriterien für diese Anwendungen nur schlecht geeignet
Reject inference in consumer credit scoring with nonignorable missing data
We generalize an empirical likelihood approach to missing data to the case of consumer credit scoring and provide a Hausman test for nonignorability of the missings.
An application to recent consumer credit data shows that our model yields parameter
estimates which are significantly different (both statistically and economically)
from the case where customers who were refused credit are ignored
The administrative structure and urban geography of the jund of Filasṭīn and the jund of al-Urdunn : the cities and districts of Palestine and East Jordan during the early Islamic, 'Abbāsid and early Fāṭamid periods
In this study, we test the strength of a cross-cultural simulation game, Ecotonos, in the development of cultural intelligence (CQ) and self-efficacy amongst business students. Cross-cultural training is perceived as an important tool to help develop cross-cultural competence in international managers. Within the training literature, a distinction is made between various types of training, roughly the more cognitive knowledge-transferring training formats and more behavioral training formats such as cultural simulation games or cross-cultural role-plays. The impact of these cross-cultural role-plays is perceived to be stronger due to the process of practicing new behavior in an intercultural safe setting. In this study, we test such a behavioral training format, Ecotonos, to investigate the impact of this cross-cultural intervention on the cultural competence of students in higher business education. This study shows that the use of the Ecotonos cross-cultural role-play supports the development of CQ, specifically metacognitive, motivational, and behavioral CQ. Next, it shows an increase in the development of confidence in cross-cultural encounters. Communication effectiveness did not increase as a result of the Ecotonos cross-cultural role-play
Reject inference in consumer credit scoring with nonignorable missing data
We generalize an empirical likelihood approach to missing data to the case of consumer credit scoring and provide a Hausman test for nonignorability of the missings. An application to recent consumer credit data shows that our model yields parameter estimates which are significantly different (both statistically and economically) from the case where customers who were refused credit are ignored
Pore-Scale Modelling of Induced-Polarization Mechanisms in Geologic Materials
This thesis is concerned with mechanistic pore-scale models, which relate the induced-polarization (IP) response of geologic materials to the underlying physical and chemical processes. Although a sound understanding of these processes is essential for the interpretation of measured IP responses, the development of suitable mechanistic models is lagging far behind the fast growing amount of experimental IP data. Therefore, the main objective of this thesis is to improve theoretical models and advance the general understanding of the polarization processes. The first development is an analytic model to predict the influence of an immiscible liquid hydrocarbon phase on the membrane-polarization mechanism occurring in electrolyte-filled pore constrictions. The hydrocarbon is modelled as an electrically insulating phase with a negatively charged surface. Magnitude and phase of the predicted electrical conductivity of hydrocarbon-contaminated materials decrease with increasing hydrocarbon saturation irrespective of whether the hydrocarbon phase is wetting or non-wetting. Only non-wetting hydrocarbon droplets with highly charged surfaces yield an increase of the magnitude with the hydrocarbon saturation and a slight increase of the phase at intermediate hydrocarbon concentrations. This prediction offers the first theoretical explanation for a similar experimentally determined relation between complex conductivity and hydrocarbon saturation. The next two parts of this thesis examine the electrode-polarization mechanism responsible for the IP response of metal-bearing materials. The polarization of uncharged metallic particles is studied based on an electrochemical model, which includes the effect of oxidation-reduction reactions at the particle surface. The full solution of the underlying Poisson-Nernst-Planck (PNP) system is presented, which allows to visualize the micro-scale manifestations of two simultaneously acting polarization mechanisms. The first mechanism is related to the dynamic charging of field-induced diffuse layers and the second is a volume-diffusion mechanism activated by reaction currents through the particle surface. For the relaxation times of both processes analytic expressions are derived and a critical particle radius is determined. While the response of particles smaller than this radius is mainly determined by the diffuse-layer polarization, the effect of the volume-diffusion mechanism becomes significant around larger particles. The model is then extended to investigate the effect of surface charge on electrode polarization. Besides the dynamic charging of field-induced diffuse layers and the volume-diffusion processes related to the reaction currents, the numeric solution of the modified PNP system reveals the action of an additional volume-diffusion process caused by the unequal transport rates of anions and cations within the static diffuse covering the charged surface. This mechanism is found to have a second-order effect on the macroscopic polarization response, which is still dominated by the first two mechanisms. While the volume-diffusion process due to the reaction currents remains practically unaffected by the surface charge, a moderate increase of the low-frequency conductivity and the relaxation time as well as a slight reduction of the polarization magnitude with the surface charge are observed if the diffuse-layer relaxation dominates, i.e. in the case of small particles. In the last part of this thesis, the coupled polarization of Stern and diffuse layers covering dielectric surfaces is treated in a generalized numeric framework. First, this framework is used to model the response of spherical particles and guide the development of an improved analytic model for the coupled polarization of Stern and diffuse layer. Subsequently, it is applied to a cylindrical pore-constriction geometry. In the limiting case of a pure diffuse-layer polarization, the corresponding numeric results can be matched by an improved analytic membrane-polarization model. In both geometries, the response of the Stern layer dominates as long as the charged surfaces are not interconnected at the system scale. With increasing degree of interconnectivity, however, the response of the diffuse layer becomes more important and in the case of fully interconnected surfaces becomes as strong as the response of the Stern layer. In summary, this thesis brings together significant improvements of analytic models for all relevant induced-polarization mechanisms: Membrane polarization, electrode polarization, and Stern- and diffuse-layer polarization. The carefully validated numeric modelling framework furthermore lays the foundation for the future investigation of more realistic geometrical configurations of the various solid and liquid phases of real geologic materials.Porenskalenmodellierung der Mechanismen der Induzierten Polarisation in Geologischen Materialien Gegenstand dieser Dissertation sind mechanistische Porenskalenmodelle, die die Induzierte Polarisation (IP) geologischer Materialien mit den ihr zugrundeliegenden physikalischen und chemischen Prozessen verknüpfen. Obwohl ein umfassendes Verständnis dieser Prozesse für die Interpretation immer neuer experimenteller IP Daten wichtig wäre, hängt die Entwicklung mechanistischer Modelle weit hinterher. Ziel dieser Dissertation ist es daher, theoretische Modelle weiterzuentwickeln und damit das grundlegende Verständnis der Polarisationsprozesse zu verbessern. Den ersten Beitrag dazu liefert ein analytisches Modell, das den Einfluss unvermischbarer flüssiger Kohlenwasserstoffe (KW) auf die Membranpolarisation in elektrolytgefüllten Porenengstellen vorhersagt. Der flüssige KW wird hier als nichtleitende Phase mit negativ geladener Oberfläche modelliert. Betrag und Phase der resultierenden elektrischen Leitfähigkeit nehmen mit zunehmendem KW-Anteil ab – unabhängig davon, ob der KW die benetzende oder die nicht-benetzende Phase ist. Nur im Falle stark negativ geladener nicht-benetzender KW-Tropfen nimmt der Betrag mit dem KW-Anteil zu. Auch die Phase durchläuft hier zunächst ein Maximum bevor sie bei hohen KW-Anteilen schließlich abfällt. Diese Vorhersage kann erstmals einen ähnlichen experimentell nachgewiesenen Zusammenhang zwischen komplexer elektrischer Leitfähigkeit und KW-Anteil theoretisch erklären. Die folgenden zwei Teile behandeln die für die starke IP Antwort metallhaltiger Materialien verantwortliche Elektrodenpolarisation. Die Polarisierung ungeladener metallischer Partikel wird mithilfe eines elektrochemischen Modells untersucht, das auch Redoxreaktionen an der Partikeloberfläche einschließt. Die hier vorgestellte vollständige Lösung des zugrundeliegenden Poisson-Nernst-Planck (PNP) Gleichungssystems ermöglicht es die mikroskopischen Auswirkungen zweier gleichzeitig ablaufender Mechanismen grafisch darzustellen: Das dynamische Laden feldinduzierter diffuser Schichten und einen Volumendiffusionsmechanismus, der von Reaktionsströmen durch die Partikeloberfläche aktiviert wird. Für die Relaxationszeiten beider Prozesse werden analytische Ausdrücke abgeleitet und ein kritischer Partikelradius bestimmt. Während das Verhalten von Partikeln mit geringerem Radius hauptsächlich mit der Polarisation der diffusen Schicht zusammenhängt, wird im Fall größerer Partikel der Volumendiffusionsmechanismus bestimmend. Im Folgenden wird dieses Modell erweitert, um die Auswirkung elektrischer Ladungen an der Metalloberfläche auf die Elektrodenpolarisation zu untersuchen. Neben der dynamischen Ladung der feldinduzierten diffusen Schichten und dem durch die Reaktionsströme bedingten Volumendiffusionsmechanismus beschreibt die numerische Lösung des erweiterten PNP Systems einen weiteren Volumendiffusionsprozess. Dieser wird durch die unterschiedlichen Anionen- und Kationenflüsse in der statischen diffusen Schicht an der geladenen Grenzfläche hervorgerufen, beeinflusst die makroskopische Antwort, allerdings nur geringfügig: Während der durch die Reaktionsströme hervorgerufene Volumendiffusionsprozess praktisch unverändert bleibt, macht sich die geladene Partikeloberfläche genau dann durch einen moderaten Anstieg von Gleichstromleitfähigkeit und Relaxationszeit sowie durch eine leichte Abnahme der Polarisationsstärke bemerkbar, wenn die Relaxation der diffusen Schicht wichtig wird, d.h. vor allem im Falle sehr kleiner Partikel. Der letzte Teil widmet sich der gleichzeitigen Polarisierung von Stern-Schicht und diffuser Schicht an der geladenen Oberfläche dielektrischer Materialien. Ein entsprechender numerischer Modellierungsansatz wird zunächst benutzt, um die Polarisierung kugelförmiger Partikel zu simulieren und die analytische Modellierung der gleichzeitigen Polarisierung von Stern- und diffuser Schicht zu verbessern. Im Folgenden wird dieser Ansatz dann auf eine zylindrische Porenengstelle angewandt. Ein zu diesem Zweck verbessertes analytisches Modell der Membranpolarisation kann die Simulationsergebnisse allerdings nur im Grenzfall einer reinen Polarisierung der diffusen Schicht erklären. Solange die geladenen Oberflächen auf der Systemskala nicht durchgehend verbunden sind dominiert – wie im Falle kugelförmiger Partikel – die Polarisierung der Stern-Schicht. Mit zunehmender Kontinuität der Schichten nimmt der Beitrag der Polarisierung der diffusen Schicht aber zu. Bilden die Oberflächen durchgehende Verbindungen, sind beide Beiträge gleich groß. Insgesamt vereint diese Dissertation wichtige Weiterentwicklungen analytischer Modelle aller relevanten Mechanismen der induzierten Polarisation: Membranpolarisation, Elektrodenpolarisation, sowie Polarisation von Stern- und diffuser Schicht. Der sorgfältig validierte numerische Modellierungsansatz bildet außerdem die Grundlage für zukünftige Untersuchungen komplexerer geometrischer Anordnungen der verschiedenen festen und flüssigen Phasen, die reale geologische Materialien besser abbilden können
К вопросу о дистанционном обучении в аэрокосмической отрасли
Данная статья содержит информацию о возможности применения дистанционного обучения в образовательном процессе для получения степени бакалавра или магистра, либо для получения сертификата о прохождении образовательного курса в области аэрокосмической инженерии. Также рассматриваются преимущества и недостатки электронного обучения в аэрокосмической сфере. Проводится сравнительный анализ различных программ дистанционного обучения в зарубежных странах по основным критериям: стоимость обучения, продолжительность и содержание курса, требования кстуденту и т.д. Кроме того, изучена распростран?нность онлайн обучения в аэрокосмической отрасли в России и выявлены возможные проблемы реализации дистанционного обучения в аэрокосмической инженерии.This article contains an information about the possibilities of applying distance learning in the educational process in order to earn bachelor's degree or master's degree, or to obtain a certificate of passing the educational course in the field of aerospace engineering. The advantages and disadvantages of e-learning in the aerospace field are also mentioned. Comparative analysis of various distance learning programs in foreign countries was made according to the main criteria: tuition fee, duration and course content, student requirements, etc. In addition, the prevalence of online learning in the aerospace industry in Russia and possible problems of implementation ofdistance learning in aerospace engineering are covered
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