Wirtschaft und Informationstechnik Bocholt
Analysis of future development opportunities for OIS (Office Information Systems) methods and tools.
(1992)
Zur Wirtschaftlichkeit aktueller Technik-gestützter Geschäftsprozesse - Ein Branchenvergleich
(1995)
In der Diskussion um Strategien zum Abbau der Arbeitslosigkeit ist der Dienstleistungssektor zum Hoffnungsträger geworden. Viele sehen das Dienstleistungsgewerbe schon als Motor des wirtschaftlichen Wachstums in der Bundesrepublik an. Allerdings übersieht diese These wechselseitige Abhängigkeiten zwischen sekundärem und tertiärem Sektor. Die empirische Analyse für den Regierungsbezirk Münster verdeutlicht, daß die Vorleistungsbeziehungen zwischen beiden Sektoren eine bedeutende Rolle spielen. Insofern hängen die Beschäftigungserfolge im Dienstleistungssektor auch von der Wettbewerbsfähigkeit der regionalen Industrie ab. Eine Förderung der Dienstleistungsbereiche ohne entsprechende Pflege der industriellen Basis erweist sich daher als fragwürdige Strategie.
Diversity Management
(2001)
Mentoring
(2001)
Menschen, Technik, Götter
(2002)
Digitale Brücken nach Nepal
(2003)
Die Erosion des Normalunternehmertums als Chance für eine notwendige Entrepreneurial Diversity
(2007)
This paper develops a framework for understanding the relationships between approaches to learning adopted by students in the context of higher education and the culture of the country they were brought up in. The paper, after examining the more widely used Kolb's learning styles, opts for another categorisation, namely the so called learning approaches developed by Entwistle and others (for example, Entwistle and Ramsden, 1983; Biggs, 1987; Entwistle, 1992; Tait, Entwistle and McCune, 1998; Biggs, Kember and Leung, 2001). Each of the main categories of learning approaches identified by his school, namely, deep, surface apathetic, and strategic are related to Hofstede's cultural dimensions, namely, power distance, individualism vs. collectivism, uncertainty avoidance, long vs. short time orientation and masculinity vs. femininity and a series of hypotheses developed that could be tested in cross cultural samples. This study would give practical hints on students moving out to study in different cultures (e.g. for higher education) and for teachers dealing with students from multiple cultures.
(PDF) Does culture influence learning styles in higher education?. Available from: https://www.researchgate.net/publication/254836756_Does_culture_influence_learning_styles_in_higher_education [accessed Jul 09 2018].
Die Erosion des Normalunternehmertums als Cance für eine notwendige Entrepreneurial Diversity
(2007)
Die Autorinnen stellen erste Ergebnisse aus ihrem Forschungsprojekt 'Vielfalt in der Unternehmerschaft: Facetten des Unternehmerinnenbildes in Deutschland' vor, in welchem u.a. folgende Fragen untersucht werden: Welches Selbstbild entwickeln Frauen zwischen dem Entschluss, unternehmerisch tätig zu werden, bis zur Gründung, Übernahme oder Weiterführung eines Unternehmens? Welche Rolle spielen hierbei staatliche Programme, aber auch Leitbilder aus der Personalentwicklung oder von beratenden Institutionen, Organisationen sowie Expertinnen bzw. Experten? Ab welchem Zeitpunkt verstehen Frauen sich selbst als erfolgreiche Unternehmerinnen und wie werden sie von anderen an diesen Prozessen beteiligten Akteuren gesehen? Es wurde folgende Arbeitshypothese zugrunde gelegt: Ein hegemoniales und einseitig männlich geprägtes Unternehmerbild verhindert, dass Frauen im gleichen Ausmaße wie Männer Unternehmen gründen, weiterführen und in wachsenden Unternehmen Arbeitgeber- und Führungsfunktionen übernehmen und damit Arbeitsplätze schaffen. Die Autorinnen stellen zur Überprüfung dieser Hypothese einige Auszüge aus den narrativen, problemzentrierten Interviews mit Unternehmerinnen und Unternehmern vor und erläutern ihre Typologie des Unternehmertums, welche die Typen 'Normalunternehmer', 'Step-by-Step', 'Crisis' und 'Bricoleur' umfasst. Angesichts der beobachteten Vielfalt des Unternehmertums plädieren sie für eine Verflüssigung des hegemonialen unternehmerischen Leitbildes und die Schaffung einer 'Entrepreneurial Diversity'
Rationale Klimaschutzpolitik
(2008)
Gaining customer loyalty is an important goal of marketing, and loyalty programs are intended to help in reaching it. Research on loyalty programs suggests that customers differentiate between loyalty to a company and loyalty to a loyalty program, yet little is known about the consequences of these two types of loyalty. Therefore, our study intends to make two main contributions: (1) improving our understanding of the constructs “program loyalty” and “company loyalty”, (2) investigating the relative impact of the two types of loyalty on preference, intention, and purchase behavior for the case of a multi-firm loyalty program. Results indicate that company loyalty influences a customer’s choice to visit a particular provider and to prefer it over competitors, but it is not a strong predictor of purchase behavior. Conversely, program loyalty is a far more important driver of purchase behavior. This implies that company loyalty primarily attracts customers to a particular provider and program loyalty ensures that once inside the store, more money is spent.
Plädoyer für eine Diversifizierung des unternehmerischen Leitbildes in Forschung und Beratung
(2012)
Seit den 1980er Jahren erlangt der Vertrauensbegriff im organisationalen Kontext eine immer größer werdende Bedeutung. Dennoch sind die Einflussfaktoren, welche auf die unterschiedlichen Arten des organisationalen Vertrauens wirken, weitestgehend unbekannt. Daher sollen in diesem Beitrag durch qualitative und quantitative Methoden zunächst die unterschiedlichen organisationalen Rahmenbedingungen zweier verschiedeneer sozialer Dienstleister eufgezeigt werden. In einem weiteren Schritt sollen mittels quantitativer Methoden die Einflussfaktoren auf die unterschiedlichen Formen des Vertrauens in Organisationen dargestellt sowie Konsequenzen für die praktische Arbeit abgeleitet werden.
Efficient tool to calculate two-dimensional optical spectra for photoactive molecular complexes
(2015)
We show that strong non-Markovian effects can be revealed by the steady-state two-dimensional (2D) photon echo spectra at asymptotic waiting times. For this, we use a simple dimer toy model that is strongly coupled to a harmonic bath with parameters typical for photoactive biomolecules. We calculate the 2D photon echo spectra employing both the numerically exact hierarchy equation of motion and the quasiadiabatic path integral approach and compare these results with approximate results from a time-nonlocal quantum master equation approach. While the latter correctly reproduces the exact population dynamics at long times, it fails at the same time to correctly describe the 2D photon echo spectra at long waiting times. The differences show that non-Markovian effects are much more important for the steady-state 2D photon echoes than for the equilibrium populations. Thus, accurate theoretical descriptions of the energy transfer dynamics in biomolecular complexes have to be based on numerically exact simulations of the environmental fluctuations when nonlinear response functions are analyzed.
When an open quantum system is driven by an external time-dependent force, the coupling of the driving to the central system is usually included, whereas the impact of the driving field on the bath is neglected. We investigate the effect of a quantum bath of linearly driven harmonic oscillators on the relaxation dynamics of a quantum two-level system which is not directly driven. In particular, we calculate the frequency-dependent response of the system when the bath is subject to Dirac and Gaussian driving pulses. We show that a time-retarded effective force on the system is induced by the driven bath which depends on the full history of the perturbation and the spectral characteristics of the underlying bath. In particular, when a structured Ohmic bath with a pronounced Lorentzian peak is considered, the dynamical response of the system to a driven bath is qualitatively different than that of the undriven bath. Specifically, additional resonances appear which can be directly associated with a Jaynes-Cummings-like effective energy spectrum.
Commonly, nanosystems are characterized by their response to time-dependent external fields in the presence of inevitable environmental fluctuations. The direct impact of the external driving on the environment is generally neglected. While this approach is satisfactory for macroscopic systems, on the nanoscale, an interaction of external fields with the environment is often unavoidable on principle. We extend the standard linear response theory of quantum dissipative systems to strongly driven baths. Significant modifications are found for two paradigm examples. First, we evaluate the polarizability of a molecule immersed in a strongly polarizable medium that responds to terahertz radiation. We find an increase of the molecular polarizability by about 30%. Second, we determine the response of a semiconductor quantum dot in close proximity to a metallic nanoparticle. Both are placed in a polarizable medium and exposed to electromagnetic irradiation. We show that the response of the quantum dot is qualitatively modified by the driven nanoparticle, including the generation of an additional channel of stimulated emission.
We present a scheme for cooling a vibrational mode of a magnetic molecular nanojunction by a spin-polarized charge current upon exploiting the interaction between its magnetic moment and the vibration. The spin-polarized charge current polarizes the magnetic moment of the nanoisland, thereby lowering its energy. A small but finite coupling between the vibration and the magnetic moment permits a direct exchange of energy such that vibrational energy can be transferred into the magnetic state. For positive bias voltages, this generates an effective cooling of the molecular vibrational mode. We determine parameter regimes for the cooling of the vibration to be optimal. Although the flowing charge current inevitably heats up the vibrational mode via Ohmic energy losses, we show that due to the magnetomechanical coupling, the vibrational energy (i.e, the effective phonon temperature) can be lowered below 50% of its initial value, when the two leads are polarized anti-parallel. In contrast to the cooling effect for positive bias voltages, net heating of the vibrational mode occurs for negative bias voltages. The cooling effect is enhanced for a stronger anti-parallel magnetic polarization of the leads, while the heating is stronger for a larger parallel polarization. Yet, dynamical cooling is also possible with parallel lead alignments when the two tunneling barriers are asymmetric.
The two-state two-path model is introduced as a minimized model to describe the quantum dynamics of an electronic wave packet in the vicinity of a conical intersection. It involves two electronic potential energy surfaces each of which hosts a pair of quasi-classical trajectories over which the wave packet is assumed to be delocalized. When both trajectories evolve dynamically either diabatically or adiabatically, the full wave packet dynamics shows only features of the dynamics around avoided level crossings in the vicinity of the conical intersection. When one trajectory evolves adiabatically whereas the other trajectory follows a diabatic evolution, quantum mechanical interference of the wave packet components on each path generates Stueckelberg oscillations in the transition probability. These are surprisingly robust against a dissipative environment and, thus, should be a marker for conical intersections.
Tunneling two-level systems (TLSs) are ubiquitous in amorphous solids, and form a major source of noise in systems such as nano-mechanical oscillators, single electron transistors, and superconducting qubits. Occurance of defect tunneling despite their coupling to phonons is viewed as a hallmark of weak defect-phonon coupling. This is since strong coupling to phonons results in significant phonon dressing and suppresses tunneling in two-level tunneling defects effectively. Here we determine the dynamics of a tunneling defect in a crystal strongly coupled to phonons incorporating the full 3D geometry in our description. Wefind that inversion symmetric tunneling is not dressed by phonons whereas other tunneling pathways are dressed by phonons and, thus, are suppressed by strong defect-phonon coupling. We provide the linear acoustic and dielectric response functions for a tunneling defect in a crystal for strong defect-phonon coupling. This allows direct experimental determination of the defect-phonon coupling. The singling out of inversion-symmetric tunneling states in single tunneling defects is complementary to their dominance of the low energy excitations in strongly disordered solids as a result of inter-defect interactions for large defect concentrations. This suggests that inversion symmetric TLSs play a unique role in the low energy properties of disordered solids.
The two-state two-path model is introduced as a minimized model to describe the quantum dynamics of an electronic wave packet in the vicinity of a conical intersection. It involves two electronic potential energy surfaces each of which hosts a pair of quasi-classical trajectories over which the wave packet is assumed to be delocalized. When both trajectories evolve dynamically either diabatically or adiabatically, the full wave packet dynamics shows only features of the dynamics around avoided level crossings in the vicinity of the conical intersection. When one trajectory evolves adiabatically whereas the other trajectory follows a diabatic evolution, quantum mechanical interference of the wave packet components on each path generates Stueckelberg oscillations in the transition probability. These are surprisingly robust against a dissipative environment and, thus, should be a marker for conical intersections.
Environmental noise leads to dephasing and relaxation in a quantum system. Often, a rigorous treatment of multiple noise sources within a system-bath approach is not possible. We discuss the influence of environmental fluctuations on a quantum system whose dynamics is dephasing already due to a phenomenologically treated additional noise source. For this situation, we develop a path-integral approach, which allows us to treat the system-environment coupling in a numerically exact way, and additionally we extend standard perturbative approaches. We observe strong deviations between the numerically exact and the perturbative results even for weak system-bath coupling. This shows that standard perturbative approaches fail for additional, even weak, system-bath couplings if the system dynamics is already dissipative.
Environmental rocking ratchet: Environmental rectification by a harmonically driven avoided crossing
(2017)
We propose a rocking ratchet designed as a symmetric quantum two-state system driven by a single periodic harmonic force and influenced symmetrically by thermal fluctuations. We show that the necessary broken symmetry can dynamically be achieved by a thermal environment that couples to the energy difference between the two states and the tunnel coupling between them. The quantum two-state system is driven by the harmonic periodic drive through its avoided crossing. The correspondingly driven dissipative quantum dynamics results on average in a finite population difference between both states. This then causes directed particle transport.