Fluid-flow approach to evaluate the information loss probability in a finite buffering switching node under heterogeneous ON/OFF input traffic sources

This paper proposes an approximation to evaluate the information loss probability in a finite buffering switch by using a fluid-flow model with heterogeneous ON/OFF input sources. The approach is based on the dominant effect of the largest negative eigenvalue of the differential equation system describing the buffer content. The proposed approximation notably reduces the computational complexity involved and is useful in evaluating the resources needed in a switched telecommunications network given a loss probability requirement constraint.     

Ground measurements for the validation of land surface temperatures derived from AATSR and MODIS data

An experimental site was set up in a large, flat and homogeneous area of rice crops for the validation of satellite derived land surface temperature (LST). Experimental campaigns were held in the summers of 2002-2004, when rice crops show full vegetation cover. LSTs were measured radiometrically along transects covering an area of 1 km². A total number of four thermal radiometers were used, which were calibrated and inter-compared through the campaigns. Radiometric temperatures were corrected for emissivity effects using field emissivity and downwelling sky radiance measurements. A database of ground-based LSTs corresponding to morning, cloud-free overpasses of Envisat/Advanced Along-Track Scanning Radiometer (AATSR) and Terra/Moderate Resolution Imaging Spectroradiometer (MODIS) is presented. Ground LSTs ranged from 25 to 32 °C, with uncertainties between ± 0.5 and ± 0.9 °C. The largest part of these uncertainties was due to the spatial variability of surface temperature. The database was used for the validation of LSTs derived from the operational AATSR and MODIS split-window algorithms, which are currently used to generate the LST product in the L2 level data. A quadratic, emissivity dependent split-window equation applicable to both AATSR and MODIS data was checked as well. Although the number of cases analyzed is limited (five concurrences for AATSR and eleven for MODIS), it can be concluded that the split-window algorithms work well, provided that the characteristics of the area are adequately prescribed, either through the classification of the land cover type and the vegetation cover, or with the surface emissivity. In this case, the AATSR LSTs yielded an average error or bias of − 0.9 °C (ground minus algorithm), with a standard deviation of 0.9 °C. The MODIS LST product agreed well with the ground LSTs, with differences comparable or smaller than the uncertainties of the ground measurements for most of the days (bias of + 0.1 °C and standard deviation of 0.6 °C, for cloud-free cases and viewing angles smaller than 60°). The quadratic split-window algorithm resulted in small average errors (+ 0.3 °C for AATSR and 0.0 °C for MODIS), with differences not exceeding ± 1.0 °C for most of the days (standard deviation of 0.9 °C for AATSR and 0.5 °C for MODIS).     

Adaptive soft k-nearest-neighbour classifiers

A novel classifier is introduced to overcome the limitations of the k-NN classification systems. It estimates the posterior class probabilities using a local Parzen window estimation with the k-nearest-neighbour prototypes (in the Euclidean sense) to the pattern to classify. A learning algorithm is also presented to reduce the number of data points to store. Experimental results in two hand-written classification problems demonstrate the potential of the proposed classification system.     

Sustainable Development and the Sustainability of Competitive Advantage: A Dynamic and Sustainable View of the Firm

Does the need for sustainable development hinder businesses’ ability to create value? Is a firm’s competitiveness negatively affected by considering that need? After quickly reviewing the main literature contributions on the relationship between business and society, and drawing from resource‐based view of the firm and sustainable development literature, this paper presents a proposal for a dynamic and sustainable view of the firm. It shows how considering the changes introduced into the competitive landscape by sustainable development influences the way in which companies develop their resources, capabilities and activities, fostering the persistence of competitive advantages based on knowledge and innovation.     

A Methodology for Modeling and Optimizing Social Systems

Abstract

A system methodology for modeling and optimizing social systems is presented. It allows constructing dynamical models formulated stochastically, i.e., their results are given by confidence intervals. The models provide optimal intervention ways to reach the stated objectives. Two optimization methods are used: (1) to test strategies and scenarios and (2) to optimize with a genetic algorithm. The application case presented is a small nonformal education Spanish business. First, the model is validated in the 2008–2012 period, and subsequently, the optimal way to obtain a maximum profit in the 2013–2025 period is obtained using the two methods.     

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)