100,214 research outputs found

    concept study for a 80% scaled Derivative LCA

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    The LCA. i s expected to incorporate advanced aerodynamic and flight control features, with high AoA capabilities and high agility . Due to our limited design data bank and lack of experience in FBW technology, several uncertainties may not be resolved even at the prototype first flight stage . Hence a study was conducted to explore the feasibility of fabricating and flight-testing a 80;6 scaled derivative aircraft to provide flight mechanics and flight control data for the LCA. This aircraft would be made from rigid-foam-FRP composite materials, using techniques developed at MAL . It would have an gross weight of 2500 kg and the Viper 22/8 engine is suggested as the powerplant because of availability. Preliminary design has been started and basic parameters are mentioned. It is felt that this experimental program will be crucial for the success of the LCA . The time element is the most challenging aspect in this situation. A 21z year time frame seems to be possible if financial and manpower support are available It is expected that this study will initiate a dialogue between is HAL and MBB to formulate a joint program for the fabrication and flight-testing of the experimental LCA.

    Multifunctions of bounded variation

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    Consider control systems described by a differential equation with a control term or, more generally, by a differential inclusion with velocity set F(t,x). Certain properties of state trajectories can be derived when it is assumed that F(t,x) is merely measurable w.r.t. the time variable t . But sometimes a refined analysis requires the imposition of stronger hypotheses regarding the time dependence. Stronger forms of necessary conditions for minimizing state trajectories can be derived, for example, when F(t,x) is Lipschitz continuous w.r.t. time. It has recently become apparent that significant addition properties of state trajectories can still be derived, when the Lipschitz continuity hypothesis is replaced by the weaker requirement that F(t,x) has bounded variation w.r.t. time. This paper introduces a new concept of multifunctions F(t,x) that have bounded variation w.r.t. time near a given state trajectory, of special relevance to control. We provide an application to sensitivity analysis

    Alarm initiated activities: Matching formats to tasks

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    This paper addresses the selection of visual alarm formats for different 'alarm initiated activities'. The activities under examination were alarm handling tasks. Seven such tasks have been identified, namely: observe, accept, analyse, investigate, correct, monitor and reset. One of the most important stages is the initial analysis of the alarm information as this determines the subsequent manner in which the information is processed. It was hypothesised that the format in which the information is presented will determine the success of the alarm handling task, hence the proposal to match formats to tasks. The findings suggest that text-based formats are best suited to tasks requiring time-based reasoning, mimic formats are best suited to tasks requiring spatial location and annunciator formats are best suited to tasks requiring recognition of spatial patterns. The importance of considering both reaction time and accuracy of response in consideration of task match was also noted. In summary, it is suggested that care needs to be taken to determine the appropriateness of the medium for any given task and the demands it places on the human operator

    On Revenue Monotonicity in Combinatorial Auctions

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    Along with substantial progress made recently in designing near-optimal mechanisms for multi-item auctions, interesting structural questions have also been raised and studied. In particular, is it true that the seller can always extract more revenue from a market where the buyers value the items higher than another market? In this paper we obtain such a revenue monotonicity result in a general setting. Precisely, consider the revenue-maximizing combinatorial auction for mm items and nn buyers in the Bayesian setting, specified by a valuation function vv and a set FF of nmnm independent item-type distributions. Let REV(v,F)REV(v, F) denote the maximum revenue achievable under FF by any incentive compatible mechanism. Intuitively, one would expect that REV(v,G)REV(v,F)REV(v, G)\geq REV(v, F) if distribution GG stochastically dominates FF. Surprisingly, Hart and Reny (2012) showed that this is not always true even for the simple case when vv is additive. A natural question arises: Are these deviations contained within bounds? To what extent may the monotonicity intuition still be valid? We present an {approximate monotonicity} theorem for the class of fractionally subadditive (XOS) valuation functions vv, showing that REV(v,G)cREV(v,F)REV(v, G)\geq c\,REV(v, F) if GG stochastically dominates FF under vv where c>0c>0 is a universal constant. Previously, approximate monotonicity was known only for the case n=1n=1: Babaioff et al. (2014) for the class of additive valuations, and Rubinstein and Weinberg (2015) for all subaddtive valuation functions.Comment: 10 page

    Towards an integrated and interoperable platform for telehealth and telecare

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    Copyright @ 2012 International Journal of Integrated Care (IJIC). This work is licensed under a (http://creativecommons.org/licenses/by/3.0) Creative Commons Attribution 3.0 Unported License.We present experience of implementing and evaluating a platform purpose designed to integrate interoperable telehealth and telecare. We chose the IEEE 11073 standards for all devices and used ZigBee wireless to support many devices concurrently and exploit its mesh networking to extend range around the entire house. We designed the home gateway to be unobtrusive; in project Hydra we used the smart meter and in other projects (Reaction, inCasa) we have developed a purpose designed plugtop ZigBee to GPRS gateway. All use common protocols and are interoperable. Technically the projects have been a success, and we have already implemented a wide range of devices on the common platform (BP, weight, SpO2, glucose, PIR, medication monitor, bed/chair sensor). Immediate feedback from participants has confirmed our goal of simplicity and convenience of use (and thus encourage adherence); and it is interesting that in discussion they then focus on the data rather than the technology. Our current goal is to exploit the potential for combination of physiological and environmental data to determine if change of habits can be detected and how this correlates with change in health. We are using this functionality to manage the frail elderly within project inCasa and we propose to present preliminary findings

    Frequency of Parental Psychopathology in Children with Attention Deficit Hyperactivity Disorder

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    Parental mental health concerns place children at a significantly greater risk of lower social, psychological and physical health than children in families not affected by mental illness. Several studies have examined the extent to which psychopathology in children are closely related to parental substance use disorders or to other mental disorders. This study intended to investigate the frequency of occurrence of parental psychopathology in children with Attention Deficit/Hyperactivity Disorder and compare the characteristics of children with and without parental psychopathology. Fifty children between 7-14 years of either sex fulfilling the ICD-10 criteria for ADHD comprised the sample of this study.It would be a chart review of in-patients and out-patients who have consulted at Kasturba Hospital, Department of Psychiatry, Manipal over a two year period. Parents diagnosed with Substance Use Disorders (SUD) and other psychiatric morbidity according to ICD-10 was compared with those parents without any psychiatric illness on various Sociodemographic, clinical characteristics. Most of the parents were in the second or third decade of their life. Of the fifty patients 41(82%) were males and 9 (18%) were females. In 36(87.0 %) of the fathers had a history of substance use disorder and 5(13.0 %) it was absent. Other morbidities were also present in both parents. The findings are discussed in light of the implications
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