Low-cost housing in Swaziland

The data assembled here was gathered while the author was acting as chief architect for the Government of Swaziland from 1971-74, under United Nations auspices, where he investigated housing conditions elsewhere in Africa and assessed their suitability for Swaziland. At the time of writing a pilot scheme of eight house types had been completed and a major project of 115 houses was under construction. The author has now returned to architectural practice in New York.     

Outsourcing im Pflegedienst

Pflegekunden vertrauen den Pflegediensten sensible Gesundheitsdaten an. Doch dieses rechtlich geschützte Vertrauen ist durch wirtschaftliche Zw?nge gef?hrdet. Viele Pflegedienste binden IT-Dienstleister in Ihre Datenverarbeitung ein und machen diese somit zu Mitwissern. Dabei gibt es einen Weg zwischen rechtlichen und wirtschaftlichen Zw?ngen.     

Criteria of progress for information systems design theories

According to Kuhn, science and progress are strongly interrelated. In this paper, we define criteria of progress for design theories. A broad analysis of the literature on information systems design science reveals that there is no consensus on the criteria of progress for design theories. We therefore analyze different concepts of progress for natural science theories. Based on well-founded criteria stemming from the philosophy of science and referring to natural science theories, we develop a set of criteria of progress for design theories. In summary, our analysis results in six criteria of progress for design theories: A design theory is partially progressive compared to another if it is ceteris paribus (1) more useful, (2) internally more consistent, (3) externally more consistent, (4) more general, (5) simpler, or (6) more fruitful of further research. Although the measurement of these criteria is not the focus of this paper, the problem of measurement cannot be totally neglected. We therefore discuss different methods for measuring the criteria based on different concepts of truth: the correspondence theory of truth, the coherence theory of truth, and the consensus theory of truth. We finally show the applicability of the criteria with an example.     

A rail-to-rail amplifier input stage with /spl plusmn/0.35%g/sub m/ fluctuation

A new scheme for achieving rail-to-rail input to an amplifier is introduced. Constant g/sub m/ is obtained by using tunable level shifters and a single differential pair. Feedback circuitry controls the level shifters in a manner that fixes the common-mode input of the differential pair, resulting in consistent and stable operation for rail-to-rail inputs. As the new technique avoids using complimentary input differential pairs, this method overcomes problems such as common-mode rejection ratio and gain-bandwidth product degradation that exist in many other designs. The circuit was fabricated in 0.5-/spl mu/m process. The resulting differential pair had a constant transconductance that varied by only /spl plusmn/0.35% for rail-to-rail input common-mode levels. The input common-mode range extended well past the supply levels of /spl plusmn/1.5V, resulting in only /spl plusmn/1% fluctuation in g/sub m/ for input common modes from -2 to 2 V.     

Reduced model to describe SPM-limited fiber transmission indispersion-managed lightwave systems

A reduced model to describe self-phase modulation (SPM)-limited fiber transmission in dispersion-managed lightwave systems is presented. By introducing a new figure of merit, the maximum transmission distance versus optical power can be determined without any numerical simulation. Together with simplified models for other nonlinear fiber effects, a useful set of design rules for a first-order performance estimation of wavelength-division multiplexed (WDM) systems is established     

Migration of divalent ions in nylon 6 films

The migration of ions through a nylon-6 film is studied by MRI. For this study the paramagnetic ions Mn²⁺ and Cu²⁺ are used as they act as a contrast agent and are detectable by MRI.     

Thermally enhanced solubility for the shrinking of a nanoink droplet in a surrounding liquid

This paper presents a theoretical investigation of the phenomenon of diffusion-dominated shrinking of a nanoparticle suspension droplet in a surrounding liquid of a different substance. The shrinking is controlled thermally by enhancing the solubility of the droplet into the surrounding medium. The model is based on the transport equations for mass, momentum and energy in spherical coordinates, considering all important thermophysical phenomena such as the transfer of energy and species over the moving interface as well as particle transport and diffusion processes within the droplet and the surrounding medium. Solutions for the interface velocity and the velocity fields are obtained, describing the diffusive nature of the problem.