Effects of alarms on control of robot teams

Annunciator driven supervisory control (ADSC) is a widely used technique for directing human attention to control systems otherwise beyond their capabilities. ADSC requires associating abnormal parameter values with alarms in such a way that operator attention can be directed toward the involved subsystems or conditions. This is hard to achieve in multirobot control because it is difficult to distinguish abnormal conditions for states of a robot team. For largely independent tasks such as foraging, however, self-reflection can serve as a basis for alerting the operator to abnormalities of individual robots. While the search for targets remains unalarmed the resulting system approximates ADSC. The described experiment compares a control condition in which operators perform a multirobot urban search and rescue (USAR) task without alarms with ADSC (freely annunciated) and with a decision aid that limits operator workload by showing only the top alarm. No differences were found in area searched or victims found, however, operators in the freely annunciated condition were faster in detecting both the annunciated failures and victims entering their cameras' fields of view. Copyright 2011 by Human Factors and Ergonomics Society, Inc. All rights reserved

Mössbauer hyperfine parameters of iron species in the course of Geobacter-mediated magnetite mineralization

Amorphous ferric iron species (ferrihydrite or akaganeite of <5 nm in size) is the only known solid ferric iron oxide that can be reductively transformed by dissimilatory iron-reducing bacteria to magnetite completely. The lepidocrocite crystallite can be transformed into magnetite in the presence of abiotic Fe(II) at elevated pH or biogenic Fe(II) with particular growth conditions. The reduction of lepidocrocite by dissimilatory iron-reducing bacteria has been widely investigated showing varying results. Vali et al. (Proc Natl Acad Sci USA 101:16121-16126, 2004) captured a unique biologically mediated mineralization pathway where the amorphous hydrous ferric oxide transformed to lepidocrocite was followed by the complete reduction of lepidocrocite to single-domain magnetite. Here, we report the 57Fe Mössbauer hyperfine parameters of the time-course samples reported in Vali et al. (Proc Natl Acad Sci USA 101:16121-16126, 2004). Both the quadrupole splittings and linewidths of Fe(III) ions decrease consistently with the change of aqueous Fe(II) and transformations of mineral phases, showing the Fe(II)-mediated gradual regulation of the distorted coordination polyhedrons of Fe 3+ during the biomineralization process. The aqueous Fe(II) catalyzes the transformations of Fe(III) minerals but does not enter the mineral structures until the mineralization of magnetite. The simulated abiotic reaction between Fe(II) and lepidocrocite in pH-buffered, anaerobic media shows the simultaneous formation of green rust and its gradual transformation to magnetite plus a small fraction of goethite. We suggested that the dynamics of Fe(II) supply is a critical factor for the mineral transformation in the dissimilatory iron-reducing cultures. © 2011 The Author(s).published_or_final_versionSpringer Open Choice, 21 Feb 201

Friedelin: A bacterial resistance modulator from Paulinia Pinnata L.

As part of the project to identify plant natural products which modulate bacterial multidrug resistance (MDR), bioassay-guided isolation of the methanol extract of Paullinia pinnata L. roots yielded four known compounds namely friedelin, â-sitosterol, â-sitosterol acetate and â-sitosterol Dglucoside. The structures were established by spectroscopic methods and comparison with published data. These compounds were tested for in vitro antibacterial and resistance modifying activities against strains of Staphylococcus aureus; SA1199B, RN4220 and XU212 possessing the Tet(K), Msr(A), and Nor(A) multidrug resistance efflux mechanisms respectively. At 10ìg/ml, none of the compounds displayed any antibacterial action but in combination with tetracycline, erythromycin andnorfloxacin, friedelin displayed a 2-fold, 4-fold and 16-fold potentiation of activities of these antibiotics against XU212, SA1199B and RN4220 possessing the Tet(K) [tetracycline resistant], Nor(A)[norfloxacin resistant] and Msr(A) [macrolide resistant] transporters respectively

Reconstructing Colonization Dynamics of the Human Parasite Schistosoma mansoni following Anthropogenic Environmental Changes in Northwest Senegal

© 2015 Van den Broeck et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. The attached file is the published version of the article

Detecting dynamic communities in opportunistic networks

In opportunistic networks, communities of mobile entities may be utilized to improve the efficiency of message forwarding. However, identifying communities that are dynamically changing in mobile environment is non-trivial. Based on random walk on graphs, in this paper we present a community detection algorithm that takes into account the aging and weight of contacts between mobile entities. Our idea originates from message-forwarding operations in opportunistic networks. We evaluate the algorithm on both computer-generated networks and real-world human mobility traces. The result shows that our proposed algorithm can find the communities and detect the changes in their structures over time. © 2009 IEEE.published_or_final_versionThe 1st International Conference on Ubiquitous and Future Networks (ICUFN 2009), Hong Kong, China, 7-9 June 2009. In Proceedings of the 1st ICUFN, 2009, p. 159-16

An agile information-architecture-driven approach for the development of user-centered interactive software

This is the author's version of the work. It is posted here for your personal use. Not for redistribution. The definitive Version of Record was published in Interacción '15: Proceedings of the XVI International Conference on Human Computer Interaction, http://dx.doi.org/10.1145/2829875.2829919.For the most part, Information Architecture processes include sets of activities and techniques to be carried out by the development team to create interactive applications effectively, involving usability concerns at every development step. In fact, plenty of process models have already been proposed to bridge the gap between User-Centered Development and Information Architecture, empowering the development team to build usable applications successfully. However, the combination of User- Centered Development and Information Architecture paradigms sometimes results in cumbersome process models containing lots of phases and activities to be considered, which increases the cycle time to have partial and validated software increments readily. As less effort has been devoted to speed up the usable Information Architecture development, the aim of this paper is to address such problem. To do so, we present Scrum-UIA, an agile and usable development process driven by the Information Architecture. This process is intended to develop web applications by splitting up responsibilities and tasks, and decreasing the time to perform technical activities, in order to readily obtain usable software increments.This work has been supported by the funding projects «eMadrid», granted by the Madrid Research Council (project code S2013/ICE-2715) and «Flexor», granted by the Spanish Government (project code TIN2014-52129-R)

Reversible writing of high-mobility and high-carrier-density doping patterns in two-dimensional van der Waals heterostructures

A key feature of two-dimensional materials is that the sign and concentration of their carriers can be externally controlled with techniques such as electrostatic gating. However, conventional electrostatic gating has limitations, including a maximum carrier density set by the dielectric breakdown, and ionic liquid gating and direct chemical doping also suffer from drawbacks. Here, we show that an electron-beam-induced doping technique can be used to reversibly write high-resolution doping patterns in hexagonal boron nitride-encapsulated graphene and molybdenum disulfide (MoS2) van der Waals heterostructures. The doped MoS2 device exhibits an order of magnitude decrease of subthreshold swing compared with the device before doping, whereas the doped graphene devices demonstrate a previously inaccessible regime of high carrier concentration and high mobility, even at room temperature. We also show that the approach can be used to write high-quality p–n junctions and nanoscale doping patterns, illustrating that the technique can create nanoscale circuitry in van der Waals heterostructures

Environmental performance indicators for assessing sustainability of projects in the Ghanaian construction industry

PURPOSE: Recent reports based on the sustainable development goals (SDGs) have revealed that no country is in line with achieving the targets of the 2030 Agenda for sustainable development, with the slowest progress being witnessed mainly on goals that are focused on the environment. This study examines environmental performance indicators for assessing the sustainability of building projects. DESIGN/METHODOLOGY/APPROACH: The study uses an explanatory sequential design with an initial quantitative instrument phase, followed by a qualitative data collection phase. An extensive critical comparative review of the literature resulted in the identification of ten environmental sustainability indicators. One hundred and sixty-seven questionnaire responses based upon these indicators from the Ghanaian construction industry were received. Data were coded with SPSS v22, analysed descriptively, and via inferential analysis. These data were then validated through semi-structured interviews with six interviewees who are fellows of their respective professional bodies, a senior academic (professor in construction project delivery) and a government official. Data obtained from the semi-structured validation interviews were analysed through the side-by-side comparison of the qualitative data with the quantitative data. FINDINGS: The findings from the study suggest that all the indicators were important in assessing building projects' environmental sustainability across the entire life cycle. Key among the identified indicators is the effects of the project on “water quality, air quality, energy use and conservation, and environmental compliance and management”. The interviewees further agreed to and confirmed the importance of these identified indicators for assessing the environmental sustainability of building projects in Ghana. ORIGINALITY/VALUE: Compared to existing studies, this study adopts the exploratory sequential design to identify and examine the critical indicators in assessing the environmental sustainability across the entire lifecycle of building projects in a typical developing country setting, i.e. Ghana. It reveals areas of prime concern in the drive to place the local construction industry on a trajectory towards achieving environmental sustainability