11,832 research outputs found

    Investigating Concrete Steel Rebar Degradation Using Some Selected Inhibitors in Marine and Microbial Media

    Get PDF
    Potential monitoring investigations were conducted on concrete steel rebar samples premixed with selected inhibitors accompanied by fixed amount of sodium chloride salt and partially immersed in sulphuric acid and sodium chloride solution. Varying concentration of potassium dichromate, potassium chromate and sodium nitrite inhibitors were used individually and synergistically in this study. The potential readings were taken in accordance with ASTM C 876 through the open circuit potential corrosion monitoring technique. Suppressive quality and dependability of the inhibitor was then assessed by the Weibull probability density distribution as an extreme value statistical modeling approach to study performance effectiveness and forecast the most effective inhibitor concentration in each media. Inhibitor effect on the compressive strengths of the reinforced concrete samples was also examined and reported. Results showed that 0.15M potassium chromate inhibitor had the best overall and individual performance in its inhibiting ability in the H2SO4 medium, while 0.68M sodium nitrite admixture was predicted as showing the lowest probability of corrosion risk in NaCl medium. Also, the best synergistic performance was shown by sample admixed with 0.06M K2Cr2O7, 0.15M K2CrO4 and 0.27M NaNO2 partially immersed in the NaCl medium. The compressive strength of concrete sample admixed with 0.03M K2Cr2O7 and 0.10M K2CrO4 was the highest amongst samples admixed with inhibitor in both media, though the control sample partially immersed in the NaCl medium had the highest overall compressive strength value

    Set-up and study of a networked control system

    Get PDF

    Expect the unexpected: the co-construction of assistive artifacts

    Get PDF
    This paper aims to explain emerging design activities within community-based rehabilitation contexts through the science of self-organization and adaptivity. It applies an evolutionary systematic worldview (Heylighen, 2011) to frame spontaneous collaboration between different local agents which produce self-made assistive artifacts. Through a process of distinction creation and distinction destruction occupational therapist, professional non-designers, caregivers and disabled people co-evolve simultaneously towards novel possibilities which embody a contemporary state of fitness. The conversation language is build on the principles of emotional seeding through stigmergic prototyping and have been practically applied as a form of design hacking which blends design time and use time. Within this process of co-construction the thought experiment of Maxwell’s Demon is used to map perceived behavior and steer the selecting process of following user-product adaptation strategies. This practice-based approach is illustrated through a case study and tries to integrate both rationality and intuition within emerging participatory design activities

    Affective Medicine: a review of Affective Computing efforts in Medical Informatics

    Get PDF
    Background: Affective computing (AC) is concerned with emotional interactions performed with and through computers. It is defined as “computing that relates to, arises from, or deliberately influences emotions”. AC enables investigation and understanding of the relation between human emotions and health as well as application of assistive and useful technologies in the medical domain. Objectives: 1) To review the general state of the art in AC and its applications in medicine, and 2) to establish synergies between the research communities of AC and medical informatics. Methods: Aspects related to the human affective state as a determinant of the human health are discussed, coupled with an illustration of significant AC research and related literature output. Moreover, affective communication channels are described and their range of application fields is explored through illustrative examples. Results: The presented conferences, European research projects and research publications illustrate the recent increase of interest in the AC area by the medical community. Tele-home healthcare, AmI, ubiquitous monitoring, e-learning and virtual communities with emotionally expressive characters for elderly or impaired people are few areas where the potential of AC has been realized and applications have emerged. Conclusions: A number of gaps can potentially be overcome through the synergy of AC and medical informatics. The application of AC technologies parallels the advancement of the existing state of the art and the introduction of new methods. The amount of work and projects reviewed in this paper witness an ambitious and optimistic synergetic future of the affective medicine field

    The black silicon method: a universal method for determining the parameter setting of a fluorine-based reactive ion etcher in deep silicon trench etching with profile control

    Get PDF
    Very deep trenches (up to 200 ”m) with high aspect ratios (up to 10) in silicon and polymers are etched using a fluorine-based plasma (SF6/O2/CHF3). Isotropic, positively and negatively (i.e. reverse) tapered as well as fully vertical walls with smooth surfaces are achieved by controlling the plasma chemistry. A convenient way to find the processing conditions needed for a vertical wall is described: the black silicon method. This new procedure is checked for three different reactive ion etchers (RIE), two parallel-plate reactors and a hexode. The influence of the RF power, pressure and gas mixture on the profile will be shown. Scanning electron microscope (SEM) photos are included to demonstrate the black silicon method, the influence of the gases on the profile, and the use of this method in fabricating microelectromechanical systems (MEMS)

    Stress related epigenetic changes may explain opportunistic success in biological invasions in Antipode mussels

    Get PDF
    Different environmental factors could induce epigenetic changes, which are likely involved in the biological invasion process. Some of these factors are driven by humans as, for example, the pollution and deliberate or accidental introductions and others are due to natural conditions such as salinity. In this study, we have analysed the relationship between different stress factors: time in the new location, pollution and salinity with the methylation changes that could be involved in the invasive species tolerance to new environments. For this purpose, we have analysed two different mussels’ species, reciprocally introduced in antipode areas: the Mediterranean blue mussel Mytilus galloprovincialis and the New Zealand pygmy mussel Xenostrobus securis, widely recognized invaders outside their native distribution ranges. The demetylathion was higher in more stressed population, supporting the idea of epigenetic is involved in plasticity process. These results can open a new management protocols, using the epigenetic signals as potential pollution monitoring tool. We could use these epigenetic marks to recognise the invasive status in a population and determine potential biopollutants

    Sustainable development : a model Indonesian SRI co-operative : this research paper is presented in partial fulfilment of the requirements for the degree of Master of International Development, Massey University, New Zealand

    Get PDF
    This research report explores how ‘sustainable livelihoods’ have been achieved at a model cooperative using the ‘System of Rice Intensification’ named SIMPATIK. To conduct the research a novel template was developed. The framework was required following a review of sustainable livelihood literature which found deficiencies with the ‘sustainable livelihoods framework’, particularly its treatment of equity, social capital, culture and agro-ecology which disqualified the framework as an appropriate approach for the research. Amekawa’s (2011) ‘Integrated Sustainable Livelihoods Framework’ which synthesises agro-ecology and the sustainable livelihoods framework is then discussed. Further work is then presented on social capital which this paper argues has a critical role in facilitating access to livelihood capitals. A discussion of the significance of culture then follows to underline its importance as a form of livelihood capital. The research then introduces an operational model that is appropriate to the local cultural, institutional and geographical context to demonstrate how livelihood capitals are linked to livelihood outcomes, a model I have labelled the ‘Apt-Integrated Sustainable Livelihoods Framework’. This framework is then informed through field research at the SIMPATIK co-operative. Impact pathways through ‘synergetic forms of social capital’ and the System of Rice Intensification (SRI) are shown indeed to lead to sustainable livelihood outcomes for research participants. The ‘sequencing’ of livelihood capitals is seen to be critical and the research culminates in the development of a ‘SRI Co-operative Template for Sustainable Livelihoods’; a transferable model that shows how SRI can be promoted as a sustainable livelihood strategy

    Learning archetypes as tools of Cybergogy for a 3D educational landscape: a structure for eTeaching in Second Life

    No full text
    This paper considers issues of validity and credibility of eTeaching using a 3D Virtual World as a delivery medium of eLearning pertaining to the transfer of authentic real life skills. It identifies the game like qualities perceived therein, recognising that these very attributes may, when experienced superficially, be a contributing factor to the potential educational demise of the platform. It goes on to examine traditional educational theories in the light of the affordances of a virtual world seeking to adapt and apply them to the construction of a new conceptual framework of a pedagogy reflecting the affordances and understanding of on-line learning which incorporates the implementation of Learning Archetypes (models of activities) to maximise the essence of a virtual world, in as much as it is able to facilitate learning experiences delimited by physical world constraints. It builds upon these ideas to develop a working model of Cybergogy and Learning Archetypes in 3D with a view to making it available to people who wish to demonstrate theoretically robust lesson and course planning. The model is then applied to three examples of eTeaching, developed as Case Studies for the purpose of critically evaluating the model, which is found to be operationally effective, accurate and flexible. Conclusions are drawn that identify the merits and challenges of implementing such a model of Cybergogy into eTeaching and eLearning conducted in Second LifeÂź

    Retail design: lighting as an atmospheric tool, creating experiences which influence consumers’ mood and behaviour in commercial spaces

    Get PDF
    Retail design is no new discipline, but a scientific approach is of rather recent date. Since atmosphere has been proven to have an influence on consumer’s behaviour from a marketing point of view, this Ph.D. focuses on the designers’ perspective. This paper addresses one aspect of atmosphere: lighting and its influence on consumers’ mood and buying behaviour. Following an introduction in the discipline of retail design, we discuss the notion of ‘atmosphere’ and its relationship to lighting. We also develop a theoretical framework as a first part of a three-part process: literature review, experiments and validation. This first part includes the development of hypotheses and research questions. We will summarise a long tradition of research into architectural physics and psychology in both retail and work environments. Additionally, we also attempt to describe the applied research category: research by design. The set-up of the first experiment, currently undertaken, is explained via its method (participants, instruments, procedure) with an analysis of the preliminary results. Furthermore, the second part - the experiments and a design - and the third part - the development of guidelines - are briefly described. Keywords: Retail Design; Lighting; Consumer Behaviour; Research By Design; Mood; Atmosphere</p
    • 

    corecore