969 resultados para lipidic cubic phase crystallization
Resumo:
Footwear is designed to reduce injury and enhance performance. However, the effect footwear has on foot and ankle kinematics currently remains unknown. Acknowledging the need for improved understanding, the aim of this study was to describe the effect footwear has on the kinematics of a multi segment foot during stance phase of walking gait.
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This report provides an overview of findings of qualitative research comprising three case studies undertaken as a part of the retrospective analysis component of Sustainable Built Environment National Research Centre (SBEnrc) Project 2.7 Leveraging R&D investment for the Australian Built Environment. These case studies (see Parts 2, 3 and 4 of this suite of reports) were undertaken to illustrate the nature of past R&D investments in Australia. This was done to complement: (i) the audit and analysis of past R&D investment undertaken by Thomas Barlow (2011); and (ii) the Construction 2030 roadmap being developed by Swinburne University of Technology and Professor Göran Roos from VTT Technical Research Centre of Finland. These documents will be the basis for the final phase of the present project - developing policy guidelines for future R&D investment in the Australian built environment. Refer also Parts 1, 2 and 3 for detail findings.
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This report discusses findings of a case study into "CADD, BIM and IPD" undertaken as a part of the retrospective analysis component of Sustainable Built Environment National Research Centre (SBEnrc) Project 2.7 Leveraging R&D investment for the Australian Built Environment. This case study investigated the evolution that has taken place in the Queensland Department of Public Works Division of Project Services during the last 20 years from: the initial implementation of computer aided design and documentation(CADD); to the experimentation with building information modelling (BIM) from the mid 2000’s; embedding integrated practice (IP); to current steps towards integrated project delivery (IPD) with the integration of contractors in the design/delivery process. This case study should be read in conjunction with Part 1 of this suite of reports.
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This report discusses findings of a case study into "Road Construction Safety" undertaken as a part of the retrospective analysis component of Sustainable Built Environment National Research Centre (SBEnrc) Project 2.7 Leveraging R&D investment for the Australian Built Environment. The Queensland Department of Transport and Main Roads (QTMR) has taken a leadership role in developing a safer working environment for road construction workers. In the past decades, a range of initiatives have been introduced to contribute to improved performance in this area. Several initiatives have been undertaken by QTMR as part of their overarching commitment to safety. Three such initiatives form the basis for this case study investigation, in order to better illustrate the nature of R&D investment and its impact on day-to-day operations and the supply chain. These are the development and implementation of: (i) the Mechanical Traffic Aid: (ii) the Thermal Imaging Camera; and (iii) the Trailer-based CCTV (camera). This case study should be read in conjunction with Part 1 of this suite of reports.
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This report discusses findings of a case study into "Green Buildings" undertaken as a part of the retrospective analysis component of Sustainable Built Environment National Research Centre (SBEnrc) Project 2.7 Leveraging R&D investment for the Australian Built Environment. The Western Australian Government (WAG) has taken a leadership role for a number of decades in developing more environmentally responsive buildings. In the past decade, considerable initiatives have been introduced to contribute to: (i) greening the stock of government buildings; and (ii) providing leadership in the development of other non-residential buildings developed commercially. This role has been informed by global, national and internal initiatives and research in this area. This case study investigates: (i) the nature of this leadership; and (ii) the role of R&D policy development; and (iii) the dissemination and impact of outcomes in the broader industry. This case study should be read in conjunction with Part 1 of this suite of reports.
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Residual amplitude modulation (RAM) mechanisms in electro-optic phase modulators are detrimental in applications that require high purity phase modulation of the incident laser beam. While the origins of RAMare not fully understood, measurements have revealed that it depends on the beam properties of the laser as well as the properties of the medium. Here we present experimental and theoretical results that demonstrate, for the first time, the dependence of RAM production in electro-optic phase modulators on beam intensity. The results show an order of magnitude increase in the level of RAM, around 10 dB, with a fifteenfold enhancement in the input intensity from 12 to 190 mW/mm 2. We show that this intensity dependent RAM is photorefractive in origin. © 2012 Optical Society of America.
Resumo:
We present experimental and theoretical results of the intensity dependence of residual amplitude modulation (RAM) production in electro-optic phase modulators. By utilizing the anisotropy of the medium, we show that RAM has a photorefractive origin.
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Vapour phase assembly has been used for the first time to prepare co-crystals in which the primary intermolecular interaction is halogen bonding. Co-crystals of the nitroxide 1,1,3,3-tetramethylisoindolin-2-yloxyl (TMIO) and 1,2-diiodotetrafluorobenzene (1,2-DITFB) are readily formed under standard sublimation conditions. Single crystal X-ray diffraction confirmed the structure of a 2:2 cyclic tetramer, (TMIO)2·(1,2-DITFB)2, which exhibits a new halogen bonding motif, with each nitroxide oxygen atom accepting two halogen bonds. Powder X-ray diffraction confirmed the homogeneity of the bulk sample. The crystalline complex was further characterized in the solid state using thermal analysis and vibrational spectroscopy (infrared and Raman). Density functional theory calculations were also used to evaluate the enthalpy of formation, electrostatic potential and unpaired electron density of the complex. These findings illustrate the preparation of co-crystals where solution state methodology is problematic and the potential of this approach for the formation of novel organic spin systems.
The increased popularity of mopeds and motor scooters : exploring usage patterns and safety outcomes
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Increased use of powered two-wheelers (PTWs) often underlies increases in the number of reported crashes, promoting research into PTW safety. PTW riders are overrepresented in crash and injury statistics relative to exposure and, as such, are considered vulnerable road users. PTW use has increased substantially over the last decade in many developed countries. One such country is Australia, where moped and scooter use has increased at a faster rate than motorcycle use in recent years. Increased moped use is particularly evident in the State of Queensland which is one of four Australian jurisdictions where moped riding is permitted for car licence holders and a motorcycle licence is not required. A moped is commonly a small motor scooter and is limited to a maximum design speed of 50 km/h and a maximum engine cylinder capacity of 50 cubic centimetres. Scooters exceeding either of these specifications are classed as motorcycles in all Australian jurisdictions. While an extensive body of knowledge exists on motorcycle safety, some of which is relevant to moped and scooter safety, the latter PTW types have received comparatively little focused research attention. Much of the research on moped safety to date has been conducted in Europe where they have been popular since the mid 20th century, while some studies have also been conducted in the United States. This research is of limited relevance to Australia due to socio-cultural, economic, regulatory and environmental differences. Moreover, while some studies have compared motorcycles to mopeds in terms of safety, no research to date has specifically examined the differences and similarities between mopeds and larger scooters, or between larger scooters and motorcycles. To address the need for a better understanding of moped and scooter use and safety, the current program of research involved three complementary studies designed to achieve the following aims: (1) develop better knowledge and understanding of moped and scooter usage trends and patterns; and (2) determine the factors leading to differences in moped, scooter and motorcycle safety. Study 1 involved six-monthly observations of PTW types in inner city parking areas of Queensland’s capital city, Brisbane, to monitor and quantify the types of PTW in use over a two year period. Study 2 involved an analysis of Queensland PTW crash and registration data, primarily comparing the police-reported crash involvement of mopeds, scooters and motorcycles over a five year period (N = 7,347). Study 3 employed both qualitative and quantitative methods to examine moped and scooter usage in two components: (a) four focus group discussions with Brisbane-based Queensland moped and scooter riders (N = 23); and (b) a state-wide survey of Queensland moped and scooter riders (N = 192). Study 1 found that of the PTW types parked in inner city Brisbane over the study period (N = 2,642), more than one third (36.1%) were mopeds or larger scooters. The number of PTWs observed increased at each six-monthly phase, but there were no significant changes in the proportions of PTW types observed across study phases. There were no significant differences in the proportions or numbers of PTW type observed by season. Study 2 revealed some important differences between mopeds, scooters and motorcycles in terms of safety and usage through analysis of crash and registration data. All Queensland PTW registrations doubled between 2001 and 2009, but there was an almost fifteen-fold increase in moped registrations. Mopeds subsequently increased as a proportion of Queensland registered PTWs from 1.2 percent to 8.8 percent over this nine year period. Moped and scooter crashes increased at a faster rate than motorcycle crashes over the five year study period from July 2003 to June 2008, reflecting their relatively greater increased usage. Crash rates per 10,000 registrations for the study period were only slightly higher for mopeds (133.4) than for motorcycles and scooters combined (124.8), but estimated crash rates per million vehicle kilometres travelled were higher for mopeds (6.3) than motorcycles and scooters (1.7). While the number of crashes increased for each PTW type over the study period, the rate of crashes per 10,000 registrations declined by 40 percent for mopeds compared with 22 percent for motorcycles and scooters combined. Moped and scooter crashes were generally less severe than motorcycle crashes and this was related to the particular crash characteristics of the PTW types rather than to the PTW types themselves. Compared to motorcycle and moped crashes, scooter crashes were less likely to be single vehicle crashes, to involve a speeding or impaired rider, to involve poor road conditions, or to be attributed to rider error. Scooter and moped crashes were more likely than motorcycle crashes to occur on weekdays, in lower speed zones and at intersections. Scooter riders were older on average (39) than moped (32) and motorcycle (35) riders, while moped riders were more likely to be female (36%) than scooter (22%) or motorcycle riders (7%). The licence characteristics of scooter and motorcycle riders were similar, with moped riders more likely to be licensed outside of Queensland and less likely to hold a full or open licence. The PTW type could not be identified in 15 percent of all cases, indicating a need for more complete recording of vehicle details in the registration data. The focus groups in Study 3a and the survey in Study 3b suggested that moped and scooter riders are a heterogeneous population in terms of demographic characteristics, riding experience, and knowledge and attitudes regarding safety and risk. The self-reported crash involvement of Study 3b respondents suggests that most moped and scooter crashes result in no injury or minor injury and are not reported to police. Study 3 provided some explanation for differences observed in Study 2 between mopeds and scooters in terms of crash involvement. On the whole, scooter riders were older, more experienced, more likely to have undertaken rider training and to value rider training programs. Scooter riders were also more likely to use protective clothing and to seek out safety-related information. This research has some important practical implications regarding moped and scooter use and safety. While mopeds and scooters are generally similar in terms of usage, and their usage has increased, scooter riders appear to be safer than moped riders due to some combination of superior skills and safer riding behaviour. It is reasonable to expect that mopeds and scooters will remain popular in Queensland in future and that their usage may further increase, along with that of motorcycles. Future policy and planning should consider potential options for encouraging moped riders to acquire better riding skills and greater safety awareness. While rider training and licensing appears an obvious potential countermeasure, the effectiveness of rider training has not been established and other options should also be strongly considered. Such options might include rider education and safety promotion, while interventions could also target other road users and urban infrastructure. Future research is warranted in regard to moped and scooter safety, particularly where the use of those PTWs has increased substantially from low levels. Research could address areas such as rider training and licensing (including program evaluations), the need for more detailed and reliable data (particularly crash and exposure data), protective clothing use, risks associated with lane splitting and filtering, and tourist use of mopeds. Some of this research would likely be relevant to motorcycle use and safety, as well as that of mopeds and scooters.
Resumo:
We examine the solution of the two-dimensional Cahn-Hilliard-reaction (CHR) equation in the xy plane as a model of Li+ intercalation into LiFePO4 material. We validate our numerical solution against the solution of the depth-averaged equation, which has been used to model intercalation in the limit of highly orthotropic diffusivity and gradient penalty tensors. We then examine the phase-change behaviour in the full CHR system as these parameters become more isotropic, and find that as the Li+ diffusivity is increased in the x direction, phase separation persists at high currents, even in small crystals with averaged coherency strain included. The resulting voltage curves decrease monotonically, which has previously been considered a hallmark of crystals that fill homogeneously.
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Chronic leg ulcers cause significant pain, cost, decreased quality of life and morbidity for a considerable segment of the older population (Graham et al., 2003a). At any given time the prevalence of patients with open leg ulcers receiving treatment is between 0.11% - 0.18% (Briggs & Closs 2003). Chronic leg ulcers occur in approximately 1 - 2% of the over 60 population in the US, UK, Europe and Australia (Baker & Stacey 1994; Johnson 1995; Lees & Lambert 1992; Margolis et al. 2002). Considerable research has been undertaken to determine the best treatment practices that will aid in the management and the healing of these ulcers, and practical and effective strategies and techniques for healing venous leg ulcers have been trialled to demonstrate their beneficial effects (Nelson et al. 2004; Cullum et al. 2001)...
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This paper investigates the use of mel-frequency deltaphase (MFDP) features in comparison to, and in fusion with, traditional mel-frequency cepstral coefficient (MFCC) features within joint factor analysis (JFA) speaker verification. MFCC features, commonly used in speaker recognition systems, are derived purely from the magnitude spectrum, with the phase spectrum completely discarded. In this paper, we investigate if features derived from the phase spectrum can provide additional speaker discriminant information to the traditional MFCC approach in a JFA based speaker verification system. Results are presented which provide a comparison of MFCC-only, MFDPonly and score fusion of the two approaches within a JFA speaker verification approach. Based upon the results presented using the NIST 2008 Speaker Recognition Evaluation (SRE) dataset, we believe that, while MFDP features alone cannot compete with MFCC features, MFDP can provide complementary information that result in improved speaker verification performance when both approaches are combined in score fusion, particularly in the case of shorter utterances.
Melting, ablation, and vapor phase condensation during atmospheric passage of the Bjurbole Meteorite
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A detailed study of the Bjurbole fusion crust using scanning electron microscopy (SEM) and energy dispersive analysis (EDS) shows that filamentary crystals and ablation spheres may form on the meteoroid surface. Filamentary crystals, hollow spheres, and porous regions of the surface point to a period of intense vapor phase activity during atmospheric passage. Filamentary crystals can be divided into three categories on the basis of bulk composition and morphology. Two types of filamentary crystals are vapor phase condensation products formed during atmospheric entry of the meteoroid. The other type forms by the interaction of seawater with the fusion surface. The density and composition of ablation spheres varies with the flight orientation of the meteorite. The size range and composition of iron-nickel spheres on the surface of Bjurbole are similar to spheres collected in the stratosphere. A comparison of stratospheric dust collections with meteorite surfaces may provide further insight into the mechanisms of meteoroid entry into planetary atmospheres.