Prototyping Dynamic Software Product Lines to evaluate run-time reconfigurations

Dynamic Software Product Lines (DSPL) encompass systems that are capable of modifying their own behavior with respect to changes in their operating environment by using run-time reconfigurations. A failure in these reconfigurations can directly impact the user experience since the reconfigurations are performed when the system is already under the users control. In this work, we prototype a Smart Hotel DSPL to evaluate the reliability-based risk of the DSPL reconfigurations, specifically, the probability of malfunctioning (Availability) and the consequences of malfunctioning (Severity). This DSPL prototype was performed with the participation of human subjects by means of a Smart Hotel case study which was deployed with real devices. Moreover, we successfully identified and addressed two challenges associated with the involvement of human subjects in DSPL prototyping: enabling participants to (1) trigger the run-time reconfigurations and to (2) understand the effects of the reconfigurations. The evaluation of the case study reveals positive results regarding both Availability and Severity. However, the participant feedback highlights issues with recovering from a failed reconfiguration or a reconfiguration triggered by mistake. To address these issues, we discuss some guidelines learned in the case study. Finally, although the results achieved by the DSPL may be considered satisfactory for its particular domain, DSPL engineers must provide users with more control over the reconfigurations or the users will not be comfortable with DSPLs.     

A kinetic interpretation of a negative time constant in impedance equivalent circuits for the dissolution/passive transition

A theoretical impedance function is proposed for the active/passive transition of nickel in an acid sulphate medium. It is considered that passivating species progressively covers the electrode surface. This approximated model predicts the appearance of negative time constants in the impedance spectra when coverage coefficient θ values for passive species are greater than 0.5.     

Generativity and moral development as predictors of value-socialization narratives for young persons across the adult life span: From lessons learned to stories shared.

Little research so far has examined storytelling as a channel of value socialization. In the present study, 129 adults from 3 age groups (18–26, 28–50, 60–75) were asked to tell stories for adolescents about 2 of their past value-learning experiences. Generative concern (D. P. McAdams & E. de St. Aubin, 1992) and moral reasoning stage level were also assessed. Stronger generative concern was predictive of a greater sense of having learned important lessons from these past events, of stronger adult value socialization investment, and of more engaging narratives for adolescents as judged by a panel of uninstructed raters. Higher levels of moral reasoning were positively related to generative concern and to a stronger sense of past lessons learned. Generativity appears important to the project of value socialization across the adult life span. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Protecting Research Subjects, Employees and Researchers: Implications for Software Engineering

Human subjects research entails risks for subjects and, to a lesser extent, for researchers. This paper introduces the common types of risks to subjects of empirical software engineering research, and how risk can be a function of the context in which the research is conducted. Risks for researchers are also discussed. Government regulation of the ethics of human subjects research is introduced using the example of the Common Rule that governs much human subjects research taking place in the United States.     

Does stress lead to a loss of team perspective?

One of the more well-established findings in the research literature is that stress leads to a restriction or narrowing of attentional focus. In the present study, we extend this research to the group context. We propose that, in a team environment, the narrowing of attention induced by stress may result in a shift in perspective from a broad team perspective to a more narrow or individualistic self-focus, and this loss of team perspective may result in degraded team performance. The results of an empirical study found that stress resulted in a narrowing of team perspective and that team perspective was a significant predictor of team performance. Moreover, when the effects of team perspective were controlled, the effects of stress on team performance were substantially weakened. These results suggest that one way in which stress impacts team performance is by narrowing or weakening the team-level perspective required for effective team behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A developmental study of shape integration over space and time.

Three experiments, with 172 Ss (aged 6–24 yrs), examined the integration of shape information over successive glances. In Exps I and II, Ss classified line drawings subtending 1–26° visual angle as possible or impossible objects. Response times and errors increased as a function of figure size for all age groups. The decline in performance with figure size was greater for children than for adults. In Exp II, Ss also performed a classification task based on only 1 of the informative regions in each figure. Performance in the 2 tasks suggested that the ability to encode shape information from a single region of the figures did not change with age. In Exp III, a simultaneous condition, in which an intact figure was presented, was compared with sequential conditions in which blank intervals of 0–3 sec separated 2 views of different parts of the figure. All Ss classified the figures most quickly and accurately in the simultaneous condition, and children were more affected by longer delays between views than adults. It is concluded that these results point to age-related improvements in sequential integration of shape information, both when integration occurs through successive glimpses over space and when information is separated only in time. (31 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Performance of an industrial biofilter from a composting plant in the removal of ammonia and VOCs after material replacement

BACKGROUND: Biofiltration is a suitable odor reduction technique for the treatment of gaseous emissions from composting processes, but little is known about the start‐up of full‐scale biofilters after material replacement and their performance after several years of operation. RESULTS: Biofilter material (wood chips used previously as bulking agent in a composting process) can effectively remove ammonia and most of the volatile organic compounds (VOCs) content, achieving removal efficiencies greater than 70% for VOCs and near 90% for ammonia immediately after material replacement. These removal efficiencies were maintained for several months after material replacement. In the studied full‐scale biofilter no lag phase was observed in the removal of ammonia whereas in the case of VOCs different patterns were detected during biofilter start‐up. For the old biofilter material, after 4 years of operation, a statistically significant decrease of removal efficiency for ammonia in comparison with the new material was detected. No statistically significant differences were found in the case of VOCs. CONCLUSIONS: Data on the emissions of several pollutants from biofilters treating composting exhaust gases have been systematically obtained. The tested filtering media presented adequate properties for biofiltration of gases emitted during the composting process. Copyright © 2009 Society of Chemical Industry     

Influence of the elimination and addition of seeds on the colour,phenolic composition and astringency of red wine

Several winemaking techniques have been developed to eliminate seeds to prevent the release of high amounts of very astringent proanthocyanidins, especially when the grapes are unripe. However, there is no scientific information on the effects of this practice. The aim of this paper is to study how the elimination and addition of seeds influence the colour, phenolic composition and astringency of red wine. The elimination of around 80% of the seeds led to a significant decrease of colour intensity and anthocyanin concentration. The addition of seeds originated wines with a greater concentration of total anthocyanin, but did not significantly affect the wine colour. These wines also presented significantly higher levels of proanthocyanidins, a greater proportion of epicatechin-3-gallate, a lower mean degree of polymerization, and, in particular, a drastic increase in astringency. Wines obtained with the elimination of seeds, on the other hand, had exactly the opposite characteristics.     

Acceptance of physical disability and attitudes toward personal appearance.

Investigated appearance management (AM) as a social–psychological variable in 322 physically disabled university students. The questionnaire included an AM and social interaction scale and measures of acceptance of disability. A tendency to regard AM as a form of compensation was associated with a tendency to view physical disability as a central or salient aspect of personal identity. Data suggest that AM is regarded by some as a means for ameliorating the social impact of a physical disability, but is expected to serve only a secondary role in impression formation. The relationship between disability acceptance and predisposition toward AM is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)