Internationalization and SMEs choice of direct export strategies and firm performance - Case study approach

In this research, we have, through the case study method, looked at differences in social mechanisms, including relationships, networks, trust, commitment, learning, and knowledge, in addition to firm performance. The differences are looked up against the direct export strategies our case firm Drytech uses, distributor, and direct to-retailer. Further, we have examined the advantages and disadvantages of the social mechanisms and firm performance within the strategies. Our findings found several differences within each variable when comparing the export strategies, which created the foundation to discuss each variable. Our discussion examined the advantages and disadvantages of all the variables within the social mechanisms and regarding firm performance. Our findings and discussion highlight the importance of relationships and networks when using both strategies. The degree of strength in the relationship and networks, we found to determine the achievability for information sharing and knowledge, trust, and commitment, especially when using a direct-to-retailer strategy, due to fewer expectations within the relationships. Using a direct-to-retailer strategy was more resource demanding due to the many contact points compared to a distributor in a given market with one contact point. For firm performance, we found profit and margins, in addition to sales growth, to be the main factors influencing firm performance when using the different export strategies. This thesis used qualitative methods as the research strategy and a single case study as a research design. Semi-structured interviews were conducted with four subjects from Drytech who have worked with their internationalization since the start using appropriate samples based on the information power model. The semi-structured interviews were formed with the help of an extensive literature review resulting in a theoretical framework. The four subjects included two subjects from sales and marketing, one business developer, and the CEO. Furthermore, we conducted observation both direct and by participating in meetings and at an exhibition in Germany. The empirical evidence was strengthened with secondary sources like websites, meeting notes, and strategy documents resulting in a chain of evidence

Magnetic instability in a sheared azimuthal flow

We study the magneto-rotational instability of an incompressible flow which rotates with angular velocity Omega(r)=a+b/r^2 where r is the radius and $a$ and b are constants. We find that an applied magnetic field destabilises the flow, in agreement with the results of Rudiger & Zhang 2001. We extend the investigation in the region of parameter space which is Rayleigh stable. We also study the instability at values of magnetic Prandtl number which are much larger and smaller than Rudiger & Zhang. Large magnetic Prandtl numbers are motivated by their possible relevance in the central region of galaxies (Kulsrud & Anderson 1992). In this regime we find that increasing the magnetic Prandtl number greatly enhances the instability; the stability boundary drops below the Rayleigh line and tends toward the solid body rotation line. Very small magnetic Prandtl numbers are motivated by the current MHD dynamo experiments performed using liquid sodium and gallium. Our finding in this regime confirms Rudiger & Zhang's conjecture that the linear magneto-rotational instability and the nonlinear hydrodynamical instability (Richard & Zahn 1999) take place at Reynolds numbers of the same order of magnitude.Comment: 4 pages, 4 figure

Magnetic shear-driven instability and turbulent mixing in magnetized protostellar disks

Observations of protostellar disks indicate the presence of the magnetic field of thermal (or superthermal) strength. In such a strong magnetic field, many MHD instabilities responsible for turbulent transport of the angular momentum are suppressed. We consider the shear-driven instability that can occur in protostellar disks even if the field is superthermal. This instability is caused by the combined influence of shear and compressibility in a magnetized gas and can be an efficient mechanism to generate turbulence in disks. The typical growth time is of the order of several rotation periods.Comment: 8 pages, 6 figures, A&A to appea

Global accretion disk simulations of magneto-rotational instability

We perform global three-dimensional simulations of accretion disks integrating the compressible, non-viscous, but diffusive MHD equations. The disk is supposed to be isothermal. We make use of the ZEUS-3D code integrating the MHD equations and added magnetic diffusivity. We measure the efficiency of the angular-momentum transport. Various model simulations delivered transport parameters of alpha_SS=0.01 to 0.05 which are consistent with several local numerical investigations. Two of the models reach a highly turbulent state at which alpha_SS is of the order of 0.1. After a certain stage of saturating of the turbulence, Reynolds stress is found to be negative (inward transport) in many of the models, whereas Maxwell stresses dominate and deliver a positive (outward) total transport. Several of the models yield strongly fluctuating Reynolds stresses, while Maxwell stresses are smooth and always transport outwards. Dynamo action is found in the accretion disk simulations. A positive dynamo-alpha is indicated in the northern hemisphere of the most prominent run, coming along with negative kinetic and current helicities (all having the opposite sign on the southern side). The dipolar structure of the magnetic field is maintained throughout the simulations, although indication for a decay of antisymmetry is found. The simulations covered relatively thick disks, and results of thin-disk dynamo models showing quadrupolar fields may not be compatible with the results presented here.Comment: 13 pages, LaTeX, submitted to A&

MHD instability in differentially rotating cylindric flows

The possibility that the magnetic shear-flow instability (MRI, Balbus-Hawley instability) might give rise to turbulence in a cylindric Couette flow is investigated through numerical simulations. The study is linear and the fluid flow is supposed to be incompressible and differentially rotating with a simple velocity profile with $\Omega = a+b/R^2$. The simplicity of the model is counterbalanced by the fact that the study is fully global in all three spatial directions with boundaries on each side; finite diffusivities are also allowed. The investigation is also carried out for several values of the azimuthal wavenumber of the perturbations in order to analyse whether non-axisymmetric modes might be preferred, which might produce, in a non-linear extension of the study, a self-sustained magnetic field. We find that with magnetic field the instability is easier to be excited than without magnetic field. The critical Reynolds number for Pm$=1$ is of order 50 independent of whether the nonmagnetic flow is stable or not. Also we find that i) the magnetic field strongly reduces the number of Taylor vortices, ii) the angular momentum is transported outwards and iii) for finite c ylinders a netto dynamo-alpha effect results which is negative for the upper part of the cylinder and which is positive for the lower part of the cylinder. For magnetic Prandtl number smaller than unity the critical Reynolds number scales with Pm$^{-0.65}$. If this was true even for very small magnetic Prandtl number (e.g. liquid sodium) the critical Reynolds number should reach the value 10$^5$ which is, however, also characteristic for nonlinear fi nite-amplitude hydrodynamic Taylor-Couette turbulence -- so that we easily have to expect the simultaneous existence of both sorts of instabi lities in cold accretion disks.Comment: 6 pages, 11 figures, submitted to A&

Zur selbsttätig sicheren Begrenzung von nuklearer Leistung und Brennstofftemperatur in innovativen Kernreaktoren

Nuclear energy probably will not contribute significantly to the future worldwide energysupply until it can be made catastrophefree. Therefore it has to be shown, that theconsequences of even largest accidents will have no major impact to the environmentof a power plant.In this paper one of the basic conditions for such a nuclear technology is discussed.Using mainly the modular pebble-bed high-temperature reactor as an example, thedesign principles, analytical methods and the level of knowledge as given today incontrolling reactivity accidents by inherent safety features of innovative nuclear reactorsare described. Complementary possibilities are shown to reach this goal with systems ofdifferent types of construction . Questions open today and resulting requirements forfuture activities are discussed .Today's knowledge credibly supports the possibility of a catastrophefree nucleartechnology with respect to reactivity event

Angular momentum transport and turbulence in laboratory models of Keplerian flows

We present angular momentum transport (torque) measurements in two recent experimental studies of the turbulent flow between independently rotating cylinders. In addition to these studies, we reanalyze prior torque measurements to expand the range of control parameters for the experimental Taylor-Couette flows. We find that the torque may be described as a product of functions that depend only on the Reynolds number, which describes the turbulent driving intensity, and the rotation number, which characterizes the effects of global rotation. For a given Reynolds number, the global angular momentum transport for Keplerian-like flow profiles is approximately 14% of the maximum achievable transport rate. We estimate that this level of transport would produce an accretion rate of $\dot{M}/\dot{M_0} \sim 10^{-3}$ in astrophysical disks. We argue that this level of transport from hydrodynamics alone could be significant.Comment: 17 pages, 7 figures, 2 tables, submitted to Astronomy & Astrophysics (2011

Auswirkungen eines spontanen Druckbehälterversagens beim HTR-Modul

The HTR-Module (High Temperature Reactor) is supposed to be a reactor, which comprises ofthe complete know-how ofHTR-technology. The consequent goal of a passive and inherent safety philosophy in reactor design has been followed. The question remains, however, whether this is also sufficient in the Gase of a spontaneous failure of the reactor pressure vessel, which is not designed as burst-proof Due to this, the assumption of the hypothetical reactor pressure vessel failure is an unalterable boundary condition for all considerations in this thesis. The first part evaluates the non-nuclear effects. Through the means of known investigations of explosions and burst processes, a comparison measure for the HTR-Module is developed. More detailed investigations of the dynamic fragment behaviour are made with the new computer programs FRAG2 and Xerxes. In the following, it is investigated in which way the burst process also implies nuclear effects. A limitation is made to be time period immediately following the burst of the vessel, meaning that corrosion of the fuel elements is not regarded and the void fraction of the pebble bed remains constant. Thus the calculated reactivities are Input data for the analysis of the stress of the Coated Particles in the fuel elements. The fast reactivity transients are calculated with means of the pointkinetic program HTRKIN and then transformed to transient stresses with use of the new program FAST2. The stresses of the CP-laysers of interest are rated with the use of comparison values. Additionally, an investigation ofthe longterm behaviour is made in such a way, that the resulting temperature increase by the reactivity input is used as an input data for the thermohydraulic analysis with regard to the changed core structure. The result of the investigations is that the shortterm transients, which will occur without any outer influence, have a relatively small hazardous potential in comparison to experimental results. The longterm transients can be handled through a fitting accident management. The way in which the possible shortterm transients result in a remaining prefailure of the Coated Particles and negatively influence the longterm behaviour still needs to be considered

Konzept einer Multimedialen Dokumentation der Steinkohlenzechen im Ruhrgebiet

Der Bergbau im Ruhrgebiet ist in vielfältiger Weise dokumentiert worden. Allerdings wurden bisher räumliche Darstellungen vernachlässigt. Im Rahmen der Dissertation wird daher ein Konzept vorgestellt, das sowohl einführende Darstellungen zum Thema Bergbau, einzelne Zechendokumentationen, vor allem aber auch kartographische Darstellungen mit einbezieht. Vorangestellt sind Bestandsanalysen zu aktuellen Aufgaben und Anwendungsfeldern in den Bereichen Kartographie, Dokumentation und Multimedia im Allgemeinen und speziell zum Thema Steinkohlenbergbau. Die Dissertation umfasst nicht nur die theoretische Herleitung des Konzeptes, sondern dieses Konzept wurde auch exemplarisch am Beispiel der Stadt Essen umgesetzt. Die dafür notwendigen technischen und gestalterischen Grundlagen werden ebenso aufgezeigt wie die derzeitigen Probleme und ein möglicher Ausbau des Systems