How useful are strategic plans for information systems?

Although much research has been done in the area of strategic planning for information systems (IS), relatively less research has focused on the output of the IS planning process, namely, the IS plan. This paper examines the usefulness of IS plans through a field survey of 136 IS executives. Results indicate that IS plans are generally perceived to be useful for supporting business objectives, improving systems integration, exploiting information technology (IT) for competitive advantage, and prioritising IS development projects. Conversely, IS plans are perceived to be less useful for clarifying the role of IS, evaluating IS performance, anticipating surprises and crisis, and adapting to unanticipated situations. Implications of these results are discussed.     

Phase-Change Materials in Optically Triggered Microactuators

Phase-change materials have been extensively used for optical data storage in commercial rewritable compact disks and digital video disks. These materials are also widely considered for next-generation phase-change random access memories to replace current Flash memories. We suggest a different application of phase-change materials in optically triggered microactuators. The suggested device consists of a thin film of a phase-change material deposited on a microfabricated cantilever. A laser-induced phase transformation in the film initiates a cantilever deflection since the transformation is accompanied by a large density change. We analyze quantitative criteria for material selection and optimization of device dimensions for the largest possible actuation angles and deflections. The resulting analytical model is both verified numerically and applied experimentally. Furthermore, we show that these cantilevers offer a convenient way to measure film stresses and film strains associated with laser-induced phase transformations.     

Time dependent processing in a parallel pipeline architecture

Pipeline architectures provide a versatile and efficient mechanism for constructing visualizations, and they have been implemented in numerous libraries and applications over the past two decades. In addition to allowing developers and users to freely combine algorithms, visualization pipelines have proven to work well when streaming data and scale well on parallel distributed-memory computers. However, current pipeline visualization frameworks have a critical flaw: they are unable to manage time varying data. As data flows through the pipeline, each algorithm has access to only a single snapshot in time of the data. This prevents the implementation of algorithms that do any temporal processing such as particle tracing; plotting over time; or interpolation, fitting, or smoothing of time series data. As data acquisition technology improves, as simulation time-integration techniques become more complex, and as simulations save less frequently and regularly, the ability to analyze the time-behavior of data becomes more important. This paper describes a modification to the traditional pipeline architecture that allows it to accommodate temporal algorithms. Furthermore, the architecture allows temporal algorithms to be used in conjunction with algorithms expecting a single time snapshot, thus simplifying software design and allowing adoption into existing pipeline frameworks. Our architecture also continues to work well in parallel distributed-memory environments. We demonstrate our architecture by modifying the popular VTK framework and exposing the functionality to the ParaView application. We use this framework to apply time-dependent algorithms on large data with a parallel cluster computer and thereby exercise a functionality that previously did not exist.     

A study of the polymerization behaviour of N-(4-phenoxy)-phenylmaleimide using DSC analysis

Summary The thermal cure of a monofunctional maleimide N-(4-phenoxy)-phenylmaleimid (1) was examined using differential scanning calorimetry (DSC). The analogous bis-maleimide bis-(4-maleimidophenyl)ether (2) was also analyzed in the same manner for comparison. Polymerization kinetics derived from scanning DSC measurements showed an order of reaction varying between n=1 and 2 for (1), compared to an order of reaction between n=2 and 3 (by multiple linear regression analysis) for (2). The overall enthalpy of polymerization (H_o) for N-(4-phenoxy)-phenylmaleimide (94kJ/mole) agrees well with that obtained for maleimide itself (89kJ/mole) using conventional calorimetric techniques indicating that polymerization appears complete within the timescale of the experiment. In contrast the analogous BMI displays a markedly lower overall polymerization enthalpy (ca. 66kJ/mole) indicating an apparent conversion of only 37%.     

Ohmic contacts to p-type Hg0.3Cd0.7Te by metalorganic chemical vapour deposition of HgTe

Ohmic contacts were obtained to p-type Hg_0.3Cd_0.7Te crystals by metalorganic chemical vapour deposition (MOCVD) of HgTe as an interface material between the crystals and the contacting metal. Deposition at a reduced temperature of 350C did not lead to an obvious change in the material performance. Electronic-transport data are given. Two acceptor levels, at 4.8 and 60 meV above the valence-band edge, were found.     

Combined infra-red and X-ray studies of β-silicon nitride and β′-sialons

Previous investigations of the replacement of silicon by aluminium and nitrogen by oxygen in -silicon nitride have been based primarily on X-ray powder diffraction studies. In the present work this technique is coupled with parallel infra-red studies. X-ray analyses of sialons over a wide composition range confirm previous observations that increasing substitution of aluminium for silicon and nitrogen for oxygen in -silicon nitride is accompanied by an increase in cell size, with no evidence of any other structural modification. Parallel infra-red analyses show shifts in certain of the infra-red absorption bands to lower wavenumbers as the degree of substitution increases. Changes in the infrared spectra at the composition Si₂Al₄N₄O₄ indicate structural modifications which are not apparent from the X-ray investigations. It is suggested that these changes are a result of the ordering of the different atom types at this composition.     

Transport anomalies and magnetic properties of Sn x Eu1.2−x Mo6S8 alloys

We have measured the resistance R, magnetoresistance, and magnetization of sintered samples of the compounds Sn _x Eu_1.2–x Mo₆S₈, where x = 0, 0.12, 0.24, and 0.48. A large resistance anomaly beginning at T ~ 100 K and extending to low temperatures is found in all of the alloys except x = 0.48, which had a high superconducting transition temperature T _c ~ 11.3 K. The resistance anomaly, which appears to be correlated with the depression of T _c, is also correlated with a large negative magnetoresistance at temperatures T 12 K. For all samples except x = 0.48, that part of the magnetoresistance attributed to spin-flip scattering is proportional to the square of the magnetization M ² and is 30–40% of R (0) for some samples. Magnetization measurements are consistent with a spin-7/2 paramagnetic behavior of Eu²⁺ ions when allowance is made for a concentration of 20–30% nonmagnetic (J = 0) Eu³⁺ ions as determined from Mössbauer measurements. The experimental results are inconsistent with predictions of dilute magnetic alloy Kondo models. We speculate that the resistance anomaly and suppression of T _c for x 0.24 are associated with a semiconductor-like behavior.Work performed under the auspices of the U.S. DOE.Work supported by NSF Research Grant DMR 78-2428.     

The history and development of the helium ion microscope

The helium ion microscope has recently emerged as a commercially available instrument. However, its roots go back more than 60 years to the development of the field ion microscope in Berlin, first reported in 1951. Over the intervening years, numerous researchers have pursued the development of a gas field ionization source with the goal of producing a suitable source for an ion microscope. This proved to be an elusive goal until early in this century when a number of discoveries led to a successful source, and shortly thereafter, an instrument fully able to exploit its advantages. Many individuals and many technical advances have come together to make this new class of microscope. The long history of this quest is reviewed along with the recent advances that led to the achievement of this milestone. A brief summary of the current status of the technology and its applications are given.     

Quasi‐equilibrium conditions of urban gravel‐bed stream channels in southern Ontario,Canada

Urban gravel‐bed stream channels in southern Ontario, Canada identified to be in a state of quasi‐equilibrium have been studied over the past 15 years and compared against rural gravel bed stream channels of the same hydrophysiographic region. Bankfull width and depth versus bankfull discharge were not found to increase as a function of increasing urbanization as has been found in many other studies. The observed annual frequency of bankfull discharge was typically less than a 1‐year return period with many sites ranging between 2 and 18 bankfull events per year with higher intensity and shorter duration urban flood responses, which further identified significant limitations in using annual peak discharge methods for predicting morphological forming flows in urban watersheds. The cumulative volume of bankfull and larger flood events from the urban stream channels were very similar to the same annual event volumes in the rural comparison study reaches. Bed material supply was found to decrease with increasing urbanization and the reduction in bed material supply appears to be off‐set by the smaller bankfull channel width, depth and access to floodplains during large flood events. Field evidence may also suggest a even greater reduction in channel width trajectory, relative to the rural setting, with expansive floodplains to maintain quasi‐equilibrium conditions as bed material supply continues to decrease with increased anthropogenic activity. Copyright © 2010 John Wiley & Sons, Ltd.     

Very low-temperature search for superconductivity in semiconducting KTaO3

A series of attempts have been made to detect the presence of superconductivity in semiconducting potassium tantalate (KTaO₃) single crystals. Semiconducting potassium tantalate has a number of properties in common with semiconducting SrTiO₃, which is superconducting below 0.3 K, with a critical temperatureT _c that varies as a function of the carrier concentration. Both KTaO₃ and SrTiO₃ are perovskite-structure oxides and both materials are so-called incipient ferroelectrics that are characterized by high dielectric constants at low temperature. These common properties suggest that superconductivity might also be observed in semiconducting potassium tantalate. In the temperature ange from 0.01 to 4.0 K, however, no evidence was found for superconductivity in KTaO₃ in the presence of magnetic fields of 10^–5–10^–4 T (i.e., 0.1–1 Oe). Below 1.5 K, the search for superconductivity in KTaO₃ was carried out using a³He-⁴He dilution refrigerator equipped with a SQUID magnetometer and an ac magnetometer. The system response was verified by measuring the paramagnetic susceptibility of Dy₂O₃-doped KTaO₃. The failure to observe superconductivity in KTaO₃, while SrTiO₃ is an established superconducting material, may be related to the fact that the latter substance assumes a tetragonal symmetry phase at 105 K, while KTaO₃ remains cubic to low temperatures.Operated by Union Carbide Corporation for the U.S. Department of Energy under contract w-7405-eng-26.