Using a multi-level tailored design process to develop a customer satisfaction survey for university evaluation

A multi-level procedure is described in order to develop a total quality management survey tool in the field of engineering academia. As a first step a review of available evaluation tools for universities is conducted, resulting in over 150 items used for evaluation purposes. Secondly all dimensions of educational evaluation used in previous research are summarized, resulting in 15 dimensions. In a third step, items are assigned to the dimensions, overlapping items were combined or removed, and item content and dimensions were adjusted to the specific conditions of the target faculty. Fourthly, the resulting twelve dimensions were used in first, investigative interviews in the target population. Results indicate that eleven dimensions sufficiently mapped all aspects of evaluation. After revising the items to improve understanding in a fifth step cognitive pretests were conducted. The final revision resulted in 83 items assigned to eleven dimensions

Wir bitten um ein differenziertes Urteil: Möglichkeiten zur Reduktion von Nondifferentiation bei Rating-Skalen

Nondifferentiation ist ein generelles Phänomen bei der Einschätzung von Meinungsgegenständen mittels Rating-Skalen: Zwischen den Meinungsgegenständen wird nicht so deutlich unterschieden, wie aufgrund der Skalen möglich. In zwei experimentellen Studien zu unterschiedlichen Meinungsgegenständen werden in der Literatur diskutierte Verfahren zur Reduzierung der Nondifferentiation zusammen mit einem hierfür bisher nicht verwendeten Verfahren (konstante Summe, KS) hinsichtlich ihres Einflusses auf Nondifferentiation verglichen. Eine erste Studie (N = 139) belegt eine signifikant erhöhte Differenzierung bei KS im Vergleich zu einem verbalen Einschub. Für eine zweite Studie werden in einer Voruntersuchung (N = 138) stark positiv und stark negativ eingeschätzte Meinungsgegenstände ausgewählt, die in der anschließenden Hauptuntersuchung (N = 200) ohne Messwiederholung bewertet werden. Hierbei werden insgesamt 3 verschiedene Verfahren zur Verbesserung der Differenzierung verwendet und einem rein verbalen Einschub gegenübergestellt. Auch hierbei erweist sich die KS generell als das Verfahren, das die höchste Differenzierung bewirkt

Mesoscopic superconductors in the London limit: equilibrium properties and metastability

We present a study of the behaviour of metastable vortex states in mesoscopic superconductors. Our analysis relies on the London limit within which it is possible to derive closed analytical expressions for the magnetic field and the Gibbs free energy. We consider in particular the situation where the vortices are symmetrically distributed along a closed ring. There, we obtain expressions for the confining Bean-Livingston barrier and for the magnetization which turns out to be paramagnetic away from thermodynamic equilibrium. At low temperature, the barrier is high enough for this regime to be observable. We propose also a local description of both thermodynamic and metastable states based on elementary topological considerations; we find structural phase transitions of vortex patterns between these metastable states and we calculate the corresponding critical fields.Comment: 24 pages, 20 figure

A dual point description of mesoscopic superconductors

We present an analysis of the magnetic response of a mesoscopic superconductor, i.e. a system of sizes comparable to the coherence length and to the London penetration depth. Our approach is based on special properties of the two dimensional Ginzburg-Landau equations, satisfied at the dual point $(\kappa = \frac{1}{\sqrt{2}}).$ Closed expressions for the free energy and the magnetization of the superconductor are derived. A perturbative analysis in the vicinity of the dual point allows us to take into account vortex interactions, using a new scaling result for the free energy. In order to characterize the vortex/current interactions, we study vortex configurations that are out of thermodynamical equilibrium. Our predictions agree with the results of recent experiments performed on mesoscopic aluminium disks.Comment: revtex, 20 pages, 9 figure

Structure and mechanical properties of low temperature magnetron sputtered nanocrystalline (nc-)Ti(N,C)/amorphous diamond like carbon (a-C:H) coatings

This paper reports on the structure and mechanical properties of ~ 2 μm thick nanocomposite (nc-) Ti(N,C)/amorphous diamond like carbon (a-C:H) coatings deposited on 100Cr6 steel substrates, using low temperature (~ 200 °C) DC reactive magnetron sputtering. The carbon content was varied with acetylene partial pressure in order to obtain single layer coatings with different a-C:H carbon phase fractions. The nanocrystalline Ti(N,C) phase is approximately stoichiometric for all coatings and the a-C:H phase fraction increases from 31 to 47 at.% as the coatings stoichiometry changed from TiC1.34 N0.51 to TiC2.48 N0.48, respectively. TiC1.34 N0.51 coatings showed the highest nanoindentation hardness (H) of ~ 14 GPa and a modulus (Er) of ~ 144 GPa; H reduced to < 6 GPa and Er to < 70 GPa for TiC2.48 N0.48 coatings. nc-Ti(N,C)/a-C:H coatings are promising candidates for applications where better matching of the modulus between a relatively low modulus substrate, hard loading support layer and low modulus-high H/E ratio top layer is required

Structure and mechanical properties of low temperature magnetron sputtered nanocrystalline (nc-)Ti(N,C)/amorphous diamond like carbon (a-C:H) coatings

This paper reports on the structure and mechanical properties of ~ 2 μm thick nanocomposite (nc-) Ti(N,C)/amorphous diamond like carbon (a-C:H) coatings deposited on 100Cr6 steel substrates, using low temperature (~ 200 °C) DC reactive magnetron sputtering. The carbon content was varied with acetylene partial pressure in order to obtain single layer coatings with different a-C:H carbon phase fractions. The nanocrystalline Ti(N,C) phase is approximately stoichiometric for all coatings and the a-C:H phase fraction increases from 31 to 47 at.% as the coatings stoichiometry changed from TiC1.34 N0.51 to TiC2.48 N0.48, respectively. TiC1.34 N0.51 coatings showed the highest nanoindentation hardness (H) of ~ 14 GPa and a modulus (Er) of ~ 144 GPa; H reduced to < 6 GPa and Er to < 70 GPa for TiC2.48 N0.48 coatings. nc-Ti(N,C)/a-C:H coatings are promising candidates for applications where better matching of the modulus between a relatively low modulus substrate, hard loading support layer and low modulus-high H/E ratio top layer is required

Mechanical and high pressure tribological properties of nanocrystalline Ti(N,C) and amorphous C:H nanocomposite coatings

This paper reports on the mechanical and high pressure tribological properties of nanocrystalline (nc-) Ti(N,C)/amorphous (a-) C:H deposited, using low temperature (∼ 200 °C) DC reactive magnetron sputtering. The mechanical properties are affected by the nc-Ti(N,C)/a-C:H phase fraction ratio. For increasing C contents (from 31 to 47 at.%) an increase of the a-C:H phase content and a degradation of the nanocrystalline phase occurs leading to a reduction in nanoindentation hardness (H) values (from 15 to 9 GPa) and reduced modulus (Er) values (from 150 to 80 GPa). A strong correlation between H/E ratio and wear performance was exhibited by the coatings. The synthesized coatings survived up to 100 m sliding distance when tested using pin-on-disc sliding configuration at > 4.5 GPa contact pressures and the measured friction coefficient values were similar for all films (μ ∼ 0.21–0.25)