252 resultados para quantum corrections to solitons


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Sequences with optimal correlation properties are much sought after for applications in communication systems. In 1980, Alltop (\emph{IEEE Trans. Inf. Theory} 26(3):350-354, 1980) described a set of sequences based on a cubic function and showed that these sequences were optimal with respect to the known bounds on auto and crosscorrelation. Subsequently these sequences were used to construct mutually unbiased bases (MUBs), a structure of importance in quantum information theory. The key feature of this cubic function is that its difference function is a planar function. Functions with planar difference functions have been called \emph{Alltop functions}. This paper provides a new family of Alltop functions and establishes the use of Alltop functions for construction of sequence sets and MUBs.

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Background Type 2 diabetes is a leading cause of morbidity and mortality in midlife and older Australian women with known modifiable risk factors for type 2 diabetes including smoking, nutrition, physical activity and obesity. In Australia little research has been done to investigate the perceived barriers to healthy lifestyle activities in midlife and older women with type 2 diabetes. Aims The primary aim of this study was to explore the level and type of perceived barriers to health promotion activities. The secondary aim was to explore the relationship of perceived barriers to smoking behaviour, fruit and vegetable intake, physical activity, and body mass index. Methods The study was a cross sectional survey of women, aged over 45 with type 2 diabetes, recruited from four metropolitan community health clinics (n = 41). Data were collected from self-report questionnaires and analysed using quantitative methods. Results Women in the study had average total barriers scores similar to those reported in the literature for women with a range of physical disabilities and illnesses. The leading barriers for this group of women were: lack of interest, concern about safety, too tired, lack of money and feeling what they do does not help. There was no association between total barriers scores and body mass index, physical activity, fruit and vegetable intake or socio-demographic variables. Conclusion This study contributes to understanding the perceptions of midlife and older women with type 2 diabetes about the level and type of barriers to healthy lifestyle activities that they experience. The participants reported a high level perceived barriers with a range of personal, social and environmental issues identified and described. This study suggests that health promotion education and interventions for risk factor reduction in women with type 2 diabetes may be enhanced by explicitly addressing perceived barriers to healthy lifestyle activities.

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Exposure to ultrafine particles (UFPs) is deemed to be a major risk affecting human health. Therefore, airborne particle studies were performed in the recent years to evaluate the most critical micro-environments, as well as identifying the main UFP sources. Nonetheless, in order to properly evaluate the UFP exposure, personal monitoring is required as the only way to relate particle exposure levels to the activities performed and micro-environments visited. To this purpose, in the present work, the results of experimental analysis aimed at showing the effect of the time-activity patterns on UFP personal exposure are reported. In particular, 24 non-smoking couples (12 during winter and summer time, respectively), comprised of a man who worked full-time and a woman who was a homemaker, were analyzed using personal particle counter and GPS monitors. Each couple was investigated for a 48-h period, during which they also filled out a diary reporting the daily activities performed. Time activity patterns, particle number concentration exposure and the related dose received by the participants, in terms of particle alveolar-deposited surface area, were measured. The average exposure to particle number concentration was higher for women during both summer and winter (Summer: women 1.8×104 part. cm-3; men 9.2×103 part. cm-3; Winter: women 2.9×104 part. cm-3; men 1.3×104 part. cm-3), which was likely due to the time spent undertaking cooking activities. Staying indoors after cooking also led to higher alveolar-deposited surface area dose for both women and men during the winter time (9.12×102 and 6.33×102 mm2, respectively), when indoor ventilation was greatly reduced. The effect of cooking activities was also detected in terms of women’s dose intensity (dose per unit time), being 8.6 and 6.6 in winter and summer, respectively. On the contrary, the highest dose intensity activity for men was time spent using transportation (2.8 in both winter and summer).

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The purpose of Business Process Management (BPM) is to increase the efficiency and effectiveness of organizational processes through improvement and innovation. Despite a common understanding that culture is an important element in these efforts, there is a dearth of theoretical and empirical research on culture as a facilitator of successful BPM. We develop the BPM culture construct and propose a validated instrument with which to measure organizational cultures’ support of BPM. The operationalization of the BPM culture concept provides a theoretical foundation for future research and a tool to assist organizations in developing a cultural environment that supports successful BPM.

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We review and discuss recent developments in best–worst scaling (BWS) that allow researchers to measure items or objects on measurement scales with known properties. We note that BWS has some distinct advantages compared with other measurement approaches, such as category rating scales or paired comparisons. We demonstrate how to use BWS to measure subjective quantities in two different empirical examples. One of these measures preferences for weekend getaways and requires comparing relatively few objects; a second measures academics' perceptions of the quality of academic marketing journals and requires comparing a significantly large set of objects. We conclude by discussing some limitations and future research opportunities related to BWS.

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Industrialised building (IB) is considered by many to have an important role to play in China's residential construction industry due to its potential for improved quality, productivity, efficiency, safety and sustainability. It is surprising, therefore, that although a large number of construction programmes have been completed in the country in recent years, very few have been built in this manner. Quite why this situation exists is unknown. The well-known problems with IB, such as the constraints placed on designer freedom, may be the cause. It is equally possible that, as is typical with developing countries such as China, cost or government issues dominate. On the other hand, in comparison with other countries, the construction industry in China has been widely criticised for its lack of modernity. Either way, there is an urgent need to assess and understand the hindrances to the adoption of IB in residential construction in order to identify what corrective measures, if any, need to be taken. Towards this end, we first identify a set of critical factors (CFs) for assessing the hindrances to IB adoption in China. This involves the analysis of research data collected by a questionnaire survey of experienced housing developers and professionals working in China's construction industry sector. Fuzzy set theory is used in the selection of the CFs. These CFs comprise, in rank order: higher initial cost; lack of skilled labour in IB; manufacturing capability and involvement issues and product quality problems; lack of supply chain; lack of codes and standards; and lack of government incentives, directives and promotion. The establishment of the CFs provides a basis for local construction sectors to better equip themselves for future implementation of IB. The findings also indicate a current need for formulating improved policies and strategies to encourage the further development of IB in China at present.

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In the recent manuscript published by Egodawatta et al. (2013), the authors investigated the build-up process of heavy metals (HMs) associated with road-deposited sediment (RDS) on residential road surfaces, and presented empirical models for the prediction of both the surface loads and build-up rates of HMs on these surfaces...

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This paper presents a rigorous and a reliable analytical procedure using finite element (FE) techniques to study the blast response of laminated glass (LG) panel and predict the failure of its components. The 1st principal stress (σ11) is used as the failure criterion for glass and the von mises stress (σv) is used for the interlayer and sealant joints. The results from the FE analysis for mid-span deflection, energy absorption and the stresses at critical locations of glass, interlayer and structural sealant are presented in the paper. These results compared well with those obtained from a free field blast test reported in the literature. The tensile strength (T) of the glass has a significant influence on the behaviour of the LG panel and should be treated carefully in the analysis. The glass panes absorb about 80% of the blast energy for the treated blast load and this should be minimised in the design.

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Purpose Intensity modulated radiotherapy (IMRT) treatments require more beam-on time and produce more linac head leakage to deliver similar doses to conventional, unmodulated, radiotherapy treatments. It is necessary to take this increased leakage into account when evaluating the results of radiation surveys around bunkers that are, or will be, used for IMRT. The recommended procedure of 15 applying a monitor-unit based workload correction factor to secondary barrier survey measurements, to account for this increased leakage when evaluating radiation survey measurements around IMRT bunkers, can lead to potentially-costly over estimation of the required barrier thickness. This study aims to provide initial guidance on the validity of reducing the value of the correction factor when applied to different radiation barriers (primary barriers, doors, maze walls and other walls) by 20 evaluating three different bunker designs. Methods Radiation survey measurements of primary, scattered and leakage radiation were obtained at each of five survey points around each of three different radiotherapy bunkers and the contribution of leakage to the total measured radiation dose at each point was evaluated. Measurements at each survey point were made with the linac gantry set to 12 equidistant positions from 0 to 330o, to 25 assess the effects of radiation beam direction on the results. Results For all three bunker designs, less than 0.5% of dose measured at and alongside the primary barriers, less than 25% of the dose measured outside the bunker doors and up to 100% of the dose measured outside other secondary barriers was found to be caused by linac head leakage. Conclusions Results of this study suggest that IMRT workload corrections are unnecessary, for 30 survey measurements made at and alongside primary barriers. Use of reduced IMRT workload correction factors is recommended when evaluating survey measurements around a bunker door, provided that a subset of the measurements used in this study are repeated for the bunker in question. Reduction of the correction factor for other secondary barrier survey measurements is not recommended unless the contribution from leakage is separetely evaluated.

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With this special issue, we draw attention to the growing and diverse field of HCI researchers exploring the interstices of food, technology and everyday practices. This special issue builds on the CHI workshop of the same name (Comber et al., 2012a), where we brought together the community of researchers that take food as a point from which to understand people and design technology. The workshop aimed toto attend to the practical and theoretical difficulties in designing for human–food interactions in everyday life’ identifying four thematic areas of food practices – health and wellbeing; sustainability; food experiences; and alternative food cultures. These practical and theoretical difficulties are evident in the papers that we present here, though the distinction between our four themes, premised by complexities of food practices, is a little less evident. Thus, in the papers that follow we explore how the social, technological, cultural and methodological intertwine in the field of human–food interaction.

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A controlled layer of multi-wall carbon nanotubes (MWCNT) was grown directly on top of fluorine-doped tin oxide (FTO) glass electrodes as a surface modifier for improving the performance of polymer solar cells. By using low-temperature chemical vapor deposition with short synthesis times, very short MWCNTs were grown, these uniformly decorating the FTO surface. The chemical vapor deposition parameters were carefully refined to balance the tube size and density, while minimizing the decrease in conductivity and light harvesting of the electrode. As created FTO/CNT electrodes were applied to bulk-heterojunction polymer solar cells, both in direct and inverted architecture. Thanks to the inclusion of MWCNT and the consequent nano-structuring of the electrode surface, we observe an increase in external quantum efficiency in the wavelength range from 550 to 650 nm. Overall, polymer solar cells realized with these FTO/CNT electrodes attain power conversion efficiency higher than 2%, outclassing reference cells based on standard FTO electrodes.

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This paper presents the details of an experimental study of a cold-formed steel hollow flange channel beam known as LiteSteel Beam (LSB) subject to combined bending and shear actions. The LSB sections are produced by a patented manufacturing process involving simultaneous cold-forming and electric resistance welding. Due to the geometry of the LSB, as well as its unique residual stress characteristics and initial geometric imperfections resultant of manufacturing processes, much of the existing research for common cold-formed steel sections is not directly applicable to LSB. Experimental and numerical studies have been carried out to evaluate the behaviour and design of LSBs subject to pure bending actions and predominant shear actions. To date, however, no investigation has been conducted into the strength of LSB sections under combined bending and shear actions. Combined bending and shear is especially prevalent at the supports of continuous span and cantilever beams, where the interaction of high shear force and bending moment can reduce the capacity of a section to well below that for the same section subject only to pure shear or moment. Hence experimental studies were conducted to assess the combined bending and shear behaviour and strengths of LSBs. Eighteen tests were conducted and the results were compared with current AS/NZS 4600 and AS 4100 design rules. AS/NZS 4600 design rules were shown to grossly underestimate the combined bending and shear capacities of LSBs and hence two lower bound design equations were proposed based on experimental results. Use of these equations will significantly improve the confidence and cost-effectiveness of designing LSBs for combined bending and shear actions.

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Drink walking, that is walking in a public place while intoxicated, is associated with increased risk of injury and fatality. Young people and males are especially prone to engaging in this behaviour, yet little is known about the factors associated with individual’s decisions to drink walk. The present research explores the role of different normative influences (friendship group norm, parent group norm, university peer group norm) and perceived risk, within an extended theory of planned behaviour (TPB) framework, in predicting young people’s self-reported drink walking intentions. One hundred and eighteen young people (aged 17-25 years) completed a survey including sociodemographic measures and extended TPB measures related to drink walking. Overall the extended TPB explained 72.8% of the variance in young people’s intentions to drink walk in the next six months with attitude, perceived behavioural control, friendship group norm, and gender (male) emerging as significant predictors. Males, as compared with females, had higher intentions to drink walk and lower perceptions of risk regarding drink walking. Together, these findings provide a clearer indication of the salient normative influences and gender differences in young pedestrian’s decisions to walk while intoxicated. Such findings can be used to inform future interventions designed to reduce injuries and fatalities associated with drink walking.

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Using the belief basis of the theory of planned behavior (TPB), the current study explored the rate of mild reactions reported by donors in relation to their first donation and the intention and beliefs of those donors with regard to returning to donate again. A high proportion of first-time donors indicated that they had experienced a reaction to blood donation. Further, donors who reacted were less likely to intend to return to donate. Regression analyses suggested that targeting different beliefs for those donors who had and had not reacted would yield most benefit in bolstering donors’ intentions to remain donating. The findings provide insight into those messages that could be communicated via the mass media or in targeted communications to retain first-time donors who have experienced a mild vasovagal reaction.

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Background In Pacific Island Countries (PICs) the epidemiology of dengue is characterized by long-term transmission of a single dengue virus (DENV) serotype. The emergence of a new serotype in one island country often indicates major outbreaks with this serotype will follow in other PICs. Objectives Filter paper (FP) cards on which whole blood or serum from dengue suspected patients had been dried was evaluated as a method for transportation of this material by standard mail delivery throughout the Pacific. Study design Twenty-two FP-dried whole blood samples collected from patients in New Caledonia and Wallis & Futuna Islands, during DENV-1 and DENV-4 transmission, and 76 FP-dried sera collected from patients in Yap State, Majuro (Republic of Marshall Islands), Tonga and Fiji, before and during outbreaks of DENV-2 in Yap State and DENV-4 in Majuro, were tested for the presence of DENV RNA, by serotype specific RT-PCR, at the Institut Louis Malardé in French Polynesia. Results The serotype of DENV could be determined, by a variety of RT-PCR procedures, in the FP-dried samples after more than three weeks of transport at ambient temperatures. In most cases, the sequencing of the envelope gene to genotype the viruses also was possible. Conclusions The serotype and genotype of DENV can be determined from FP-dried serum or whole blood samples transported over thousands of kilometers at ambient, tropical, temperatures. This simple and low-cost approach to virus identification should be evaluated in isolated and resource poor settings for surveillance for a range of significant viral diseases.