Development and flight test of a helicopter compact, portable, precision landing system concept

An airborne, radar-based, precision approach concept is being developed and flight tested as a part of NASA's Rotorcraft All-Weather Operations Research Program. A transponder-based beacon landing system (BLS) applying state-of-the-art X-band radar technology and digital processing techniques, was built and is being flight tested to demonstrate the concept feasibility. The BLS airborne hardware consists of an add-on microprocessor, installed in conjunction with the aircraft weather/mapping radar, which analyzes the radar beacon receiver returns and determines range, localizer deviation, and glide-slope deviation. The ground station is an inexpensive, portable unit which can be quickly deployed at a landing site. Results from the flight test program show that the BLS concept has a significant potential for providing rotorcraft with low-cost, precision instrument approach capability in remote areas

QuizMap: Open social student modeling and adaptive navigation support with TreeMaps

In this paper, we present a novel approach to integrate social adaptive navigation support for self-assessment questions with an open student model using QuizMap, a TreeMap-based interface. By exposing student model in contrast to student peers and the whole class, QuizMap attempts to provide social guidance and increase student performance. The paper explains the nature of the QuizMap approach and its implementation in the context of self-assessment questions for Java programming. It also presents the design of a semester-long classroom study that we ran to evaluate QuizMap and reports the evaluation results. © 2011 Springer-Verlag Berlin Heidelberg

Individual and peer comparison open learner model visualisations to identify what to work on next

Open learner models (OLM) can support self-regulated learning, collaborative interaction, and navigation in adaptive educational systems. Previous research has found that learners have a range of preferences for learner model visualisation. However, research has focused mainly on visualisations that are available in a single system, meaning that not all visualisations have been compared to each other. We present a study using screen shots of OLM visualisations for individuals and for comparing one's own learner model to the models of other individuals or the group, to define visualisations that students would be able to use to identify their next steps, across a wider range of options

Investigation of phonon behavior in Pr2NiMnO6 by micro-Raman spectroscopy

The temperature dependence of phonon excitations and the presence of spin phonon coupling in polycrystalline Pr2NiMnO6 samples were studied using micro-Raman spectroscopy and magnetometry. Magnetic properties show a single ferromagnetic-to-paramagnetic transition at 228 K and a saturation magnetization close to 4.95 \muB/f.u.. Three distinct Raman modes at 657, 642, and 511 cm-1 are observed. The phonon excitations show a clear hardening due to anharmonicity from 300 K down to 10 K. Further, temperature dependence of the 657 cm-1 mode shows only a small softening. This reflects the presence of a relatively weak spin-phonon coupling in Pr2NiMnO6 contrary to other double perovskites previously studied.Comment: 10 pages, 4 fig

Time‐Series Prediction Approaches to Forecasting Deformation in Sentinel‐1 InSAR Data

Time series of displacement are now routinely available from satellite InSAR and are used for flagging anomalous ground motion, but not yet forecasting. We test conventional time series forecasting methods such as SARIMA and supervised machine learning approaches such as LSTM compared to simple function extrapolation. We focus initially on forecasting seasonal signals and begin by characterising the time‐series using sinusoid fitting, seasonal decomposition and autocorrelation functions. We find that the three measures are broadly comparable but identify different types of seasonal characteristic. We use this to select a set of 310 points with highly seasonal characteristics and test the three chosen forecasting methods over prediction windows of 1‐9 months. The lowest overall median RMSE values are obtained for SARIMA when considering short term predictions ( 6 months). Machine learning methods (LSTM) perform less well. We then test the prediction methods on 2000 randomly selected points with a range of seasonalities and find that simple extrapolation of a constant function performed better overall than any of the more sophisticated time series prediction methods. Comparisons between seasonality and RMSE show a small improvement in performance with increasing seasonality. This proof‐of‐concept study demonstrates the potential of time‐series prediction for InSAR data but also highlights the limitations of applying these techniques to non‐periodic signals or individual measurement points. We anticipate future developments, especially to shorter timescales, will have a broad range of potential applications, from infrastructure stability to volcanic eruptions

Conceptualising ethical capital in social enterprises

Purpose – In popular culture, ethics and morality are topical (Giroux 1994), heightened by recent attention to the banking industry and pay awards, monopoly capitalism, global warming and sustainability. Yet, surprisingly, little attention is given to these in the narrative of the conceptualisation of social enterprise or social entrepreneurship – nor in the academic research on the sector. Current conceptualisations of social enterprise fail to fully satisfy the spirit of the movement which advances a narrative that social enterprises: are more like businesses than voluntary organisations; are more entrepreneurial than public service delivery; use business models but are not just in it for the money. A focus on the economic implies a business model where deep tensions lie. A focus on social capital offers a different frame of reference, yet both these conceptualisations fail to fully identify the phenomenon that is social enterprise. The objective of this paper is to fill that gap. Ethical capital is offered here as an alternative and unrecognised conceptualisation in the field of social enterprise. Design/methodology/approach – This paper is exploratory in nature - a tentative piece of theorising that brings together the authors‟ perspectives on ethical capital to offer a new frame of reference on social enterprise. It sets out to investigate some of the issues in order to provoke further research. As authors, we felt it important to theoretically explore the concept and discuss several themes to provoke a response. All need further research to tease out the detail. We start by outlining the current conceptualisations of social enterprise, then move on to theorising ethical capital using three broad themes; theme 1 discusses the levels of ethical capital, bridging from the private sector into the social sector. Theme 2 deconstructs the ethics of social enterprise and theme 3 questions moral agency through a conventional and enforcing enterpriser or the greater good through a critical and creative moral enterpriser. Findings – This paper very much aims at starting the process of intellectual debate about the notion of ethical capital in social enterprises. The conclusions of this paper outline further research questions that need to be addressed in order to fully develop this concept. Originality/value – It is argued that the current ideology of the neo-classical economic paradigm pursues interests towards the self and erodes the moral basis of association. The outcome leaves society with a problem of low ethical virtue. The implications of this paper are that social enterprises maximise ethical virtue beyond any other form of organisation and as such create value beyond their missions and values. This paper offers value in the understanding of social enterprise through fresh insight into its conceptualisation. A critical perspective is adopted toward the current literature. This paper sheds new light on our understanding of the sector, providing practitioners, business support agencies and academics alike with a conceptualisation that has not been explored before

Progressor: Social navigation support through open social student modeling

The increased volumes of online learning content have produced two problems: how to help students to find the most appropriate resources and how to engage them in using these resources. Personalized and social learning have been suggested as potential ways to address these problems. Our work presented in this paper combines the ideas of personalized and social learning in the context of educational hypermedia. We introduce Progressor, an innovative Web-based tool based on the concepts of social navigation and open student modeling that helps students to find the most relevant resources in a large collection of parameterized self-assessment questions on Java programming. We have evaluated Progressor in a semester-long classroom study, the results of which are presented in this paper. The study confirmed the impact of personalized social navigation support provided by the system in the target context. The interface encouraged students to explore more topics attempting more questions and achieving higher success rates in answering them. A deeper analysis of the social navigation support mechanism revealed that the top students successfully led the way to discovering most relevant resources by creating clear pathways for weaker students. © 2013 Taylor and Francis Group, LLC