Promoting traits into model-driven development

Traits, as sets of behaviors, can provide a good mechanism for reusability. However, they are limited in important ways and are not present in widely used programming and modeling languages and hence are not readily available for use by mainstream developers. In this paper, we add UML associations and other modeling concepts to traits and apply them to Java and C++ through model-driven development. We also extend traits with required interfaces so dependencies at the semantics level become part of their usage, rather than simple syntactic capture. All this is accomplished in Umple, a textual modeling language based upon UML that allows adding programming constructs to the model. We applied the work to two case studies. The results show that we can promote traits to the modeling level along with the improvement in flexibility and reusability.     

What knowledge is important to a software professional?

Efforts to develop licensing requirements, curricula, or training programs for software professionals should consider the experience of the practitioners who actually perform the work. We surveyed software professionals representing a wide variety of industries, job functions, and countries to learn which educational topics have proved most important to them in their careers and to identify the topics for which their education or current knowledge could be improved     

Word-frequency and phonological-neighborhood effects on verbal short-term memory.

Immediate memory span and maximal articulation rate were assessed for word sets differing in frequency, word-neighborhood size, and average word-neighborhood frequency. Memory span was greater for high- than low-frequency words, greater for words from large than small phonological neighborhoods, and greater for words from high- than low-frequency phonological neighborhoods. Maximal articulation rate was also facilitated by word frequency, phonological-neighborhood size, and neighborhood frequency. In a final study all 3 lexical variables were found to influence the recall outcome for individual words. These effects of phonological-word neighborhood on memory performance suggest that phonological information in long-term memory plays an active role in recall in short-term-memory tasks, and they present a challenge to current theories of short-term memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Synthesis of novel magnetic iron metal-silica (Fe-SBA-15) and magnetite-silica (Fe(3)O(4)-SBA-15) nanocomposites with a high iron content using temperature-programed reduction

Magnetic iron metal-silica and magnetite-silica nanocomposites have been prepared via temperature-programed reduction (TPR) of an iron oxide-SBA-15 (SBA: Santa Barbara Amorphous) composite. TPR of the starting SBA-15 supported Fe(2)O(3) generated Fe(3)O(4) and FeO as stepwise intermediates in the ultimate formation of Fe-SBA-15. The composite materials have been characterized by means of x-ray diffraction, high resolution transmission electron microscopy and SQUID (superconducting quantum interference device) magnetometry. The Fe oxide and metal components form a core, as nanoscale particles, that is entrapped in the SBA-15 pore network. Fe(3)O(4)-SBA-15 and Fe-SBA-15 exhibited superparamagnetic properties with a total magnetization value of 17?emu?g(-1). The magnetite-silica composite (at an Fe(3)O(4) loading of 30%?w/w) delivered a magnetization that exceeded values reported in the literature or obtained with commercial samples. Due to the high pore volume of the mesoporous template, the magnetite content can be increased to 83%?w/w with a further enhancement of magnetization.     

Elastic anisotropy and extreme Poisson’s ratios in single crystals

The relationship between elastic anisotropy and extreme Poisson’s ratio behaviour (either positive or negative) in single-crystalline materials has been investigated using experimentally determined single-crystal elastic constants for a wide range of solid materials. This makes use of a recently proposed elastic anisotropy index that is applicable to all crystal symmetries. For many real materials we find a striking correlation between the value of the elastic anisotropy index and the magnitudes of maximum and minimum Poisson’s ratios this is independent of crystal symmetry. This structure–property relationship provides new examples of auxetics and shows that negative Poisson’s ratios are actually not uncommon among many classes of inorganic (and organic) materials, including elemental metals, alloys, ionic solids, molecular solids and giant covalent networks.     

A metamodel for the compact but lossless exchange of execution traces

Understanding the behavioural aspects of a software system can be made easier if efficient tool support is provided. Lately, there has been an increase in the number of tools for analysing execution traces. These tools, however, have different formats for representing execution traces, which hinders interoperability and limits reuse and sharing of data. To allow for better synergies among trace analysis tools, it would be beneficial to develop a standard format for exchanging traces. In this paper, we present a graph-based format, called compact trace format (CTF), which we hope will lead the way towards such a standard. CTF can model traces generated from a variety of programming languages, including both object-oriented and procedural ones. CTF is built with scalability in mind to overcome the vast size of most interesting traces. Indeed, the design of CTF is based on the idea that call trees can be transformed into more compact ordered acyclic directed graphs by representing similar subtrees only once. CTF is also supported by our trace analysis tool SEAT (Software Exploration and Analysis Tool).