314 resultados para Lots closed


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This paper presents the development and experimental validation of a prototype system for online estimation and compensation of wind disturbances onboard small Rotorcraft unmanned aerial systems (RUAS). The proposed approach consists of integrating a small pitot-static system onboard the vehicle and using simple but effective algorithms for estimating the wind speed in real time. The baseline flight controller has been augmented with a feed-forward term to compensate for these wind disturbances, thereby improving the flight performance of small RUAS in windy conditions. The paper also investigates the use of online airspeed measurements in a closed-loop for controlling the RUAS forward motion without the aid of a global positioning system (GPS). The results of more than 80 flights with a RUAS confirm the validity of our approach.

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The long-term vision of economic security and social participation for people with a disability held by disability activists and policy-makers has not been realised on a global scale. This is despite the implementation of various poverty alleviation initiatives by international and national governments. Indeed within advanced Western liberal democracies, the inequalities and poverty gaps have widened rather than closed. This article is based on findings from a historical-comparative policy and discourse analysis of disability income support system in Australia and the Basic Income model. The findings suggest that a model such as Basic Income, grounded in principles of social citizenship, goes some way to maintaining an adequate level of subsistence for people with a disability. The article concludes by presenting some challenges and a commitment to transforming income support policy.

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Background: Many preterm neonates display difficulty establishing suck-feeding competence in the weeks following birth. Ineffective management of transitional feeding issues may cause patient complications, and can contribute to increased length of stay. Aims: Given that many neonatal nurseries appear to vary in their neonatal feeding management practices, the aim of this study was to investigate and document the routine level of support and intervention currently provided for preterm neonates with transitional feeding issues across the various level II (special care) nurseries (SCNs) in Queensland, Australia. Methods: A questionnaire was mailed to all Queensland SCNs in 2005 (n = 36). The questionnaire contained a series of closed-choice and short-answer questions designed to obtain information from each SCN regarding their current practices for managing transitional feeding issues in preterm neonates. Results were confirmed during a follow-up phone call. Results: Responses were obtained from 29 SCNs (80.6%). None of these nurseries reported having any formal, written policies regarding the management of transitional feeding issues in preterm neonates. Wide variations were reported in relation to the suck-feeding assessments and interventions used by staff within the various SCNs. Of the 29 nurseries, 4 (13.8%) reported using checklists or assessments to judge readiness for suck-feeds, and 5 (17.2%) reported using pulse oximetry to judge tolerance of suck-feeding attempts. Eighteen SCNs (62.1%) reported offering some form of active intervention to assist neonates with transitional feeding issues, with the most common intervention techniques reported being non-nutritive sucking during tube feeds, pre-feeding oral stimulation, and actively pacing suck-feeds. Twenty-two SCNs (75.4%) reported having access to a lactation consultant to assist mothers with breastfeeding issues. Conclusions: Differences were reported in the routine management of transitional feeding issues in preterm neonates across the various SCNs in Queensland. It is suggested that evidence based guidelines need to be developed, and that, in order to do this, further research studies are required to determine current best practice, as well as to answer remaining questions. © 2008 Elsevier Ireland Ltd. All rights reserved.

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The literature around Library 2.0 remains largely theoretical with few empirical studies and is particularly limited in developing countries such as Indonesia. This study addresses this gap and aims to provide information about the current state of knowledge on Indonesian LIS professionals’ understanding of Library 2.0. The researchers used qualitative and quantitative approaches for this study, asking thirteen closed- and open-ended questions in an online survey. The researchers used descriptive and in vivo coding to analyze the responses. Through their analysis, they identified three themes: technology, interactivity, and awareness of Library 2.0. Respondents demonstrated awareness of Library 2.0 and a basic understanding of the roles of interactivity and technology in libraries. However, overreliance on technology used in libraries to conceptualize Library 2.0 without an emphasis on its core characteristics and principles could lead to the misalignment of limited resources. The study results will potentially strengthen the research base for Library 2.0 practice as well as inform LIS curriculum in Indonesia so as to develop practitioners who are able to adapt to users’ changing needs and expectations. It is expected that the preliminary data from this study could be used to design a much larger and more complex future research project in this area.

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Endoplasmatic reticulum aminopeptidase 1 (ERAP1) is a multifunctional enzyme involved in trimming of peptides to an optimal length for presentation by major histocompatibility complex (MHC) class I molecules. Polymorphisms in ERAP1 have been associated with chronic inflammatory diseases, including ankylosing spondylitis (AS) and psoriasis, and subsequent in vitro enzyme studies suggest distinct catalytic properties of ERAP1 variants. To understand structure-activity relationships of this enzyme we determined crystal structures in open and closed states of human ERAP1, which provide the first snapshots along a catalytic path. ERAP1 is a zinc-metallopeptidase with typical H-E-X-X-H-(X)18-E zinc binding and G-A-M-E-N motifs characteristic for members of the gluzincin protease family. The structures reveal extensive domain movements, including an active site closure as well as three different open conformations, thus providing insights into the catalytic cycle. A K 528R mutant strongly associated with AS in GWAS studies shows significantly altered peptide processing characteristics, which are possibly related to impaired interdomain interactions.

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This paper investigates several competing procedures for computing the prices of vanilla European options, such as puts, calls and binaries, in which the underlying model has a characteristic function that is known in semi-closed form. The algorithms investigated here are the half-range Fourier cosine series, the half-range Fourier sine series and the full-range Fourier series. Their performance is assessed in simulation experiments in which an analytical solution is available and also for a simple affine model of stochastic volatility in which there is no closed-form solution. The results suggest that the half-range sine series approximation is the least effective of the three proposed algorithms. It is rather more difficult to distinguish between the performance of the halfrange cosine series and the full-range Fourier series. However there are two clear differences. First, when the interval over which the density is approximated is relatively large, the full-range Fourier series is at least as good as the half-range Fourier cosine series, and outperforms the latter in pricing out-of-the-money call options, in particular with maturities of three months or less. Second, the computational time required by the half-range Fourier cosine series is uniformly longer than that required by the full-range Fourier series for an interval of fixed length. Taken together,these two conclusions make a case for pricing options using a full-range range Fourier series as opposed to a half-range Fourier cosine series if a large number of options are to be priced in as short a time as possible.

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This book is a collection of three large-cast plays written in response to a very specific problem. My work as a teacher of drama often required me to locate a script that would somehow miraculously work for a cast of unknown number and gender, and most likely uneven skills and enthusiasm, who I hadn’t even met yet. It’s a familiar dilemma for teachers and students of drama in education contexts, at whatever level you’re teaching. I’d first addressed this creative problem with scripts such as Gate 38 (2010). I had tried using scripts that already existed, but found they required such extensive editing to suit the parameters of cast and performance duration that I may as well have been writing them myself. Even in the setting of a closed studio, in altering these plays I felt I was bending the vision of the playwright, and certainly their narrative structure, out of shape. Everyone who’s attempted to stage a performance with a large cast of students in an educational setting knows it takes time to truly connect with a play, its social contexts, themes and characters. It also takes a lot of time to get on top of the practicalities of learning, rehearsing, directing and running a performance with young people. Often the curtain goes up on something unfinished and unstable. I was looking for ways to reduce the complexity of staging a script, while maintaining the potential of this process as a site of rich, enjoyable learning. Two of the plays (Duty Free and Please Be Seated) are comprised of multiple monologues, combined with music-driven ensemble sequences. The monologues enable individuals to develop and polish their own performances, work in small groups, and cut down on the laborious detail of directing naturalistic scenes based in character interaction. The third (Australian Drama) involves a lot of duologues, meaning that its rehearsal process can happily employ that mainstay of the drama classroom: small group work. There’s plenty of room to move in terms of gender-blind casting as well. Please be Seated is mainly young women. The scripts also contain ensemble-based interludes which are non-verbal, music driven, with a choreographic element. They have also springboarded further explorations in form. The ethical and aesthetic complexities of verbatim works; the interaction between music and theatre; and meta-concerns related to the performing of performance: ‘how can the act of acting ‘acted’. The narratives of all three of these plays are deliberately open, enabling the flexible casting and on-the hop editing that large-group, time-poor processes sometimes necessitate. Duty Free is about the overseas ‘adventures’ of young people. Please Be Seated is based in verbatim text about young people falling in and out of love. Australian Drama is about young people in a drama classroom trying to connect with each other and put their own shine on dull fragments of the theatrical canon. The plays were published as a collection in hardcopy and digital editions by Playlab Press in 2015. Please be Seated is a co-write with a large group. These co-author’s names are listed in the publication, and below in ‘additional information’.

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This paper presents a motion control system for tracking of attitude and speed of an underactuated slender-hull unmanned underwater vehicle. The feedback control strategy is developed using the Port-Hamiltonian theory. By shaping of the target dynamics (desired dynamic response in closed loop) with particular attention to the target mass matrix, the influence of the unactuated dynamics on the controlled system is suppressed. This results in achievable dynamics independent of stable uncontrolled states. Throughout the design, the insight of the physical phenomena involved is used to propose the desired target dynamics. Integral action is added to the system for robustness and to reject steady disturbances. This is achieved via a change of coordinates that result in input-to-state stable (ISS) target dynamics. As a final step in the design, an anti-windup scheme is implemented to account for limited actuator capacity, namely saturation. The performance of the design is demonstrated through simulation with a high-fidelity model.

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In this paper, we address the problem of stabilisation of robots subject to nonholonommic constraints and external disturbances using port-Hamiltonian theory and smooth time-invariant control laws. This should be contrasted with the commonly used switched or time-varying laws. We propose a control design that provides asymptotic stability of an manifold (also called relative equilibria)-due to the Brockett condition this is the only type of stabilisation possible using smooth time-invariant control laws. The equilibrium manifold can be shaped to certain extent to satisfy specific control objectives. The proposed control law also incorporates integral action, and thus the closed-loop system is robust to unknown constant disturbances. A key step in the proposed design is a change of coordinates not only in the momentum, but also in the position vector, which differs from coordinate transformations previously proposed in the literature for the control of nonholonomic systems. The theoretical properties of the control law are verified via numerical simulation based on a robotic ground vehicle model with differential traction wheels and non co-axial centre of mass and point of contact.

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A profluorescent nitroxide possessing an isoindoline nitroxide moiety linked to a perylene fluorophore was developed to monitor radical mediated degradation of melamine-formaldehyde crosslinked polyester coil coatings in an industry standard accelerated weathering tester. Trapping of polyester-derived radicals (most likely C-radicals) that are generated during polymer degradation leads to fluorescent closed-shell alkoxy amines, which was used to obtain time-dependent degradation profiles to assess the relative stability of different polyesters towards weathering. The nitroxide probe couples excellent thermal stability and satisfactory photostability with high sensitivity and enables detection of free radical damage in polyesters under conditions that mimic exposure to the environment on a time scale of hours rather than months or years required by other testing methods. There are indications that the profluorescent nitroxide undergoes partial photo-degradation in the absence of polymer-derived radicals. Unexpectedly, it was also found that UV-induced fragmentation of the NO–C bond in closed-shell alkoxy amines leads to regeneration of the profluorescent nitroxide and the respective C-radical. The maximum fluorescence intensity that could be achieved with a given probe concentration is therefore not only determined by the amount of polyester radicals formed during accelerated weathering, but also by the light-driven side reactions of the profluorescent nitroxide and the corresponding alkoxy amine radical trapping products. Studies to determine the optimum probe concentration in the polymer matrix revealed that aggregation and re-absorption effects lowered the fluorescence intensity at higher concentrations of the profluorescent nitroxide, but too low probe concentrations, where these effects would be avoided, were not sufficient to trap the amount of polyester radicals formed upon weathering. The optimized experimental conditions were used to assess the impact of temperature and UV irradiance on polymer degradation during accelerated weathering.

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The aim of this study was to asses results obtained from a range of commonly performed lower extremity “open and closed” chain kinetic tests used for predicting foot function and correlate these test findings to data obtained from the Zebris WinFDM-T system®. When performed correctly these tests are thought to be indicators of lower extremity function. Podiatrists frequently perform examinations of joint and muscle structures to understand biomechanical function; however the relationship between these routine tests and forces generated during the gait cycle are not always well understood. This can introduce a degree of variability in clinical interpretation which creates conjecture regarding the value of these tests.

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Australia's child protection systems and the provision of out-of-home care, in particular, have been subject to sustained criticism for decades from dozens of official inquiries and reviews. It is now well established that many children in state care are treated significantly less well than required by relevant legal frameworks and community standards. Much attention and significant resources have been directed toward trying to ameliorate this ‘wicked problem’ and yet it continues. This article focuses on one reason the problems persists, namely the secrecy and closed cultures that characterize relevant organizations which reinforce strategies of denial that avoid acknowledging or dealing with ‘uncomfortable knowledge’. It is a situation many people in child protection systems confront. It is, for example, when we know abuse is taking place, or when they see or are ourselves party to corrupt or negligent practices. It is knowing that important ethical principles are being abrogated. We draw on recent official reports and inquiries noting the repeated calls for greater transparency and independent oversight. An argument is made for a default position of total transparency subject to caveats that protect privacy and any investigation underway. An account of what this can look like is offered.

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Large numbers of Mesenchymal stem/stromal cells (MSCs) are required for clinical relevant doses to treat a number of diseases. To economically manufacture these MSCs, an automated bioreactor system will be required. Herein we describe the development of a scalable closed-system, packed bed bioreactor suitable for large-scale MSCs expansion. The packed bed was formed from fused polystyrene pellets that were air plasma treated to endow them with a surface chemistry similar to traditional tissue culture plastic. The packed bed was encased within a gas permeable shell to decouple the medium nutrient supply and gas exchange. This enabled a significant reduction in medium flow rates, thus reducing shear and even facilitating single pass medium exchange. The system was optimised in a small-scale bioreactor format (160 cm2) with murine-derived green fluorescent protein-expressing MSCs, and then scaled-up to a 2800 cm2 format. We demonstrated that placental derived MSCs could be isolated directly within the bioreactor and subsequently expanded. Our results demonstrate that the closed system large-scale packed bed bioreactor is an effective and scalable tool for large-scale isolation and expansion of MSCs.

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One imperfection in housing markets is imperfect knowledge about legal interests such as ground leases. Both actual reduced legal interest as well as uncertainty surrounding rights and future lease payments for houses constructed on leased land may affect prices relative to houses built on freehold land. We use regression analysis of sales prices of condominium transactions in Helsinki to examine the effect ground leases have on house prices. We find that prices on condominiums constructed on leased lots are discounted at least 5 %, on average. In addition, we see that the announcement of potentially large increases in base rents upon renewal contributes to the discount.

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The increasing rate of child sexual abuse and child trafficking has become a serious concern for national and international policy makers. Because these acts are criminal, result in serious harms to the child, and occur in closed scenarios where the situation is concealed, it is very important for people who become aware of the acts to report the incidents to the appropriate authority. Reporting of incidents could help provide justice to the victim and penalize the perpetrators. In addition, it would help us to understand the nature and magnitude of the problem. The objective of this chapter is first to review the Indian legislation concerning mandatory reporting of child abuse and neglect, and second to consider the potential for mandatory reporting of two categories of child maltreatment in particular in the Indian context: sexual abuse and child trafficking.