64 resultados para Energy methods


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Issue addressed: Many children consume excessive amounts of energy-dense, nutrient-poor (EDNP) or 'extra' foods and low intakes of fruit and vegetables. The aim of this study was to examine the associations between EDNP foods and ascertain whether certain EDNP foods and beverages are more likely to be eaten in association with other EDNP foods.

Methods: A cross-sectional representative population survey of children in preschool (n=764), and of school students in Years K, 2 and 4 (n=1,560) and in Years 6, 8 and 10 (n=1,685) residing in the Hunter New England region of New South Wales, Australia. Dietary data were collected using a short food frequency questionnaire. Multivariate logistic regression models examined the association between EDNP foods and fruit and vegetable intake. Data were stratified by sex and age cohort.

Results: More frequent consumption of some EDNP food types was significantly associated with more frequent consumption of other EDNP foods. Fast food and soft drinks consumption were associated with each other as well as with fried potato and salty snacks; and with lower intakes of fruit and vegetables in some but not all age groups.

Conclusion: The positive associations found between EDNP foods point towards the existence of a high-risk group of children who frequently consume a variety of EDNP foods and drinks.

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The building sector consumes around 30–40 per cent of the primary energy in most developed countries. The importance of labelling buildings as a national strategy for energy efficiency is well recognized worldwide. The last 10–15 years have seen an emergence of programmes in different parts of the world. As seen in the United States, European Union, South America and Asia, there is a collection of rating systems or tools internationally, designed with the intention of evaluating the design, construction and operation of buildings. This study presents an overview and critical reflection on the progress on building energy labelling techniques in recent years. The scope of labelling, methodology and methods of implementation are discussed in detail.

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Background: It has been suggested that those who are habitually high caffeine consumers ingest greater quantities of snack foods both in and outside the laboratory. Sugar-sweetened beverages (SSBs) are a major contributor to caffeine consumption and evidence links SSB consumption with poor dietary intake.

Objective: To determine whether varying the concentration of caffeine in SSBs influences snack food consumption and energy intake.

Methods: Caffeine taste thresholds were assessed using the International Standards Organization method for assessing taste sensitivity. In a crossover study design, participants (n=23, 26±5 years old, 58% female) were provided with a standardized meal on 4 days and simultaneously consumed SSBs with varied levels of caffeine (0, 0.67, 1.16, and 1.65 mM). The intake of food and beverage was recorded following each meal session.

Results: A one way between groups analysis of variance revealed no significant main effect of caffeine concentration on consumption of SSBs [F (3, 92)=0.154, p=0.927] or food [F (3, 92)=0.305, p=0.822]. Pearson correlation analysis identified no significant correlations between the amount of food and SSB consumed (R=−0.031–0.415, p=0.062–0.893), or the amount of food and SSB consumed with body mass index and waist circumference (R=0.000 to −0.380, p=0.073–0.999). An individual's oral sensitivity to caffeine was not associated with SSB consumption (R=0.045 to −0.309, p=0.152–0.839) or the consumption of food (R=−0.052 to −0.327, p=0.128–0.812).

Conclusions: The concentration of caffeine in SSBs did not influence the amount of food or SSB consumed.

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Despite significant advancements in wireless sensor networks (WSNs), energy conservation remains one of the most important research challenges. Proper organization of nodes (clustering) is one of the major techniques to expand the lifespan of the whole network through aggregating data at the cluster head. The cluster head is the backbone of the entire cluster. That means if a cluster head fails to accomplish its function, the received and collected data by cluster head can be lost. Moreover, the energy consumption following direct communications from sources to base stations will be increased. In this paper, we propose a type-2 fuzzy based self-configurable cluster head selection (SCCH) approach to not only consider the selection criterion of the cluster head but also present the cluster backup approach. Thus, in case of cluster failure, the system still works in an efficient way. The novelty of this protocol is the ability of handling communication uncertainty, which is an inherent operational aspect of sensor networks. The experiment results indicate SCCH performs better than other recently developed methods.

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Objectives
Evaluate the predictive validity of ActiGraph energy expenditure equations and the classification accuracy of physical activity intensity cut-points in preschoolers.

Methods
Forty children aged 4–6 years (5.3±1.0 years) completed a ~150-min room calorimeter protocol involving age-appropriate sedentary, light and moderate-to vigorous-intensity physical activities. Children wore an ActiGraph GT3X on the right mid-axillary line of the hip. Energy expenditure measured by room calorimetry and physical activity intensity classified using direct observation were the criterion methods. Energy expenditure was predicted using Pate and Puyau equations. Physical activity intensity was classified using Evenson, Sirard, Van Cauwenberghe, Pate, Puyau, and Reilly, ActiGraph cut-points.

Results
The Pate equation significantly overestimated VO2 during sedentary behaviors, light physical activities and total VO2 (P<0.001). No difference was found between measured and predicted VO2 during moderate-to vigorous-intensity physical activities (P = 0.072). The Puyau equation significantly underestimated activity energy expenditure during moderate-to vigorous-intensity physical activities, light-intensity physical activities and total activity energy expenditure (P<0.0125). However, no overestimation of activity energy expenditure during sedentary behavior was found. The Evenson cut-point demonstrated significantly higher accuracy for classifying sedentary behaviors and light-intensity physical activities than others. Classification accuracy for moderate-to vigorous-intensity physical activities was significantly higher for Pate than others.

Conclusion
Available ActiGraph equations do not provide accurate estimates of energy expenditure across physical activity intensities in preschoolers. Cut-points of ≤25counts⋅15 s−1 and ≥420 counts⋅15 s−1 for classifying sedentary behaviors and moderate-to vigorous-intensity physical activities, respectively, are recommended.

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The Intergovernmental Panel on Climate Change and the McKinsey Greenhouse Gas abatement studies have highlighted reduction of building energy consumption as a primary cost-effective element in the abatement of Global Warming. Nevertheless, the energy investigation in most of our existing building stock remains at a novice level at best. Building sub-metering, by which we mean any secondary, hourly, metering (after the main) of various circuits, provides substantial information on when and where energy is used in specific buildings. Furthermore, combining this information with external weather data provides information beyond basic metering results. This paper discusses three case studies and explains how sub-metering, augmented by external solar and temperature data, benefits energy management and identified problems. It explains how different methods of analysing energy usage allowed: justifiable sizing of a solar photovoltaic system, with a calculated Cooling Degree Unit, identified the absence of savings from a proprietary chiller controller, and the energy variation due to user schedules and external conditions indicated anomalies in energy use. The advantages of wireless access are noted. Extracting information in graphical formats suggests better strategies to understand and control energy use.

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Steel pipelines, buried under the soil and protected by the combination of protective coatings and cathodic protection (CP), are used for oil and gas transportation. These pipelines are one of the critical infrastructures for energy transportation and therefore became lifelines of modern society. The deterioration of the external surfaces of transmission pipelines is a serious problem and is caused mainly by coating and/or CP failure leading to the loss of integrity of pipelines. To avoid such damage, there is a need of techniques which are able to locate active corrosion sites, monitor corrosion, and evaluate corrosion damage. Fundamental understanding of such processes occurring on coated pipelines (with various types of defects in coatings as well as pipe) in complex soil environment is necessary for the development of such techniques. Numerous laboratory techniques, i.e., electrochemical impedance spectroscopy based, polarisation measurements based, mathematical simulations, direct observation etc. have been used to develop fundamental understanding, simulate and evaluate corrosion occurring in oil and gas pipelines under various operating conditions. Given the complex nature of the pipeline corrosion, application of these laboratory techniques in field measurements as well as in understanding the corrosion mechanisms is lacking. This paper presents an overview of investigations, based on electrochemical techniques, for simulation and evaluation of pipeline corrosion in laboratory.

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 Background: The Dutch Obesity Intervention in Teenagers (DOiT) programme is an evidence-based obesity prevention programme tailored to adolescents attending the first two years of prevocational education in the Netherlands. The initial programme showed promising results during an effectiveness trial. The programme was adapted and prepared for nationwide dissemination. To gain more insight into the process of translating evidence-based approaches into ‘real world’ (i.e., ‘natural’) conditions, our research aims were to evaluate the impact of the DOiT-implementation programme on adolescents’ adiposity and energy balance-related behaviours during natural dissemination and to explore the mediating and moderating factors underlying the DOiT intervention effects.
Methods: We conducted a cluster-controlled implementation trial with 20 voluntary intervention schools (n=1002 adolescents) and 9 comparable control schools (n = 484 adolescents). We measured adolescents’ body height and weight, skinfold thicknesses, and waist circumference. We assessed adolescents’ dietary and physical activity behaviours by means of self-report. Data were collected at baseline and at 20-months follow-up. We used multivariable multilevel linear or logistic regression analyses to evaluate the intervention effects and to test the hypothesised behavioural mediating factors. We checked for potential effect modification by gender, ethnicity and education level.
Results: We found no significant intervention effects on any of the adiposity measures or behavioural outcomes. Furthermore, we found no mediating effects by any of the hypothesised behavioural mediators. Stratified analyses for gender showed that the intervention was effective in reducing sugar-containing beverage consumption in girls (B = -188.2 ml/day; 95% CI = -344.0; -32.3). In boys, we found a significant positive intervention effect on breakfast frequency (B = 0.29 days/week; 95% CI = 0.01; 0.58). Stratified analyses for education level showed an adverse intervention effect (B = 0.09; 95% CI = 0.02; 0.16) on BMI z-scores for adolescents attending the vocational education track.
Conclusions: Although not successful in changing adolescents’ adiposity, the DOiT-implementation programme had some beneficial effects on specific obesity-related behaviours in subgroups. This study underlines the difficulty of translating intervention effectiveness in controlled settings to real world contexts. Adaptations to the implementation strategy are needed in order to promote implementation as intended by the teachers.

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Governments in Australia are faced with policy implementation that mandates higher energy efficient housing (Foran, Lenzen & Dey 2005). To this effect, the National Construction Code (NCC) 2013 stipulates the minimum energy performance for residential buildings as 114MJ/m2 per annum or 6 stars on an energy rating scale. Compliance with this minimum is mandatory but there are several methods through which residential buildings can be rated to comply with the deemed to satisfy provisions outlined in the NCC. FirstRate5 is by far the most commonly used simulation software used in Victoria, Australia. Meanwhile, Building Information Modelling (BIM), using software such as ArchiCAD has gained a foothold in the industry. The energy simulation software within ArchiCAD, EcoDesigner, enables the reporting on the energy performance based on BIM elements that contain thermal information. This research is founded on a comparative study between FirstRate5 and EcoDesigner. Three building types were analysed and compared. The comparison finds significant differences between simulations, being, measured areas, thermal loads and potentially serious shortcomings within FirstRate5, that are discussed along with the future potential of a fully BIM-integrated model for energy rating certification in Victoria. © 2014, The Association for Computer-Aided Architectural Design Research in Asia (CAADRIA), Hong Kong.

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Background: Emerging evidence indicates that consumers of alcohol mixed with energy drink (AmED) self-report lower odds of risk-taking after consuming AmED versus alcohol alone. However, these studies have been criticized for failing to control for relative frequency of AmED versus alcohol-only consumption sessions. These studies also do not account for quantity of consumption and general alcohol-related risk-taking propensity. The aims of the present study were to (i) compare rates of risk-taking in AmED versus alcohol sessions among consumers with matched frequency of use and (ii) identify consumption and person characteristics associated with risk-taking behavior in AmED sessions. Methods: Data were extracted from 2 Australian community samples and 1 New Zealand community sample of AmED consumers (n = 1,291). One-fifth (21%; n = 273) reported matched frequency of AmED and alcohol use. Results: The majority (55%) of matched-frequency participants consumed AmED and alcohol monthly or less. The matched-frequency sample reported significantly lower odds of engaging in 18 of 25 assessed risk behaviors in AmED versus alcohol sessions. Similar rates of engagement were evident across session type for the remaining behaviors, the majority of which were low prevalence (reported by <15%). Regression modeling indicated that risk-taking in AmED sessions was primarily associated with risk-taking in alcohol sessions, with increased average energy drink (ED) intake associated with certain risk behaviors (e.g., being physically hurt, not using contraception, and driving while over the legal alcohol limit). Conclusions: Bivariate analyses from a matched-frequency sample align with past research showing lower odds of risk-taking behavior after AmED versus alcohol consumption for the same individuals. Multivariate analyses showed that risk-taking in alcohol sessions had the strongest association with risk-taking in AmED sessions. However, hypotheses of increased risk-taking post-AmED consumption were partly supported: Greater ED intake was associated with increased likelihood of specific behaviors, including drink-driving, sexual behavior, and aggressive behaviors in the matched-frequency sample after controlling for alcohol intake and risk-taking in alcohol sessions. These findings highlight the need to consider both personal characteristics and beverage effects in harm reduction strategies for AmED consumers.

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The constrained battery power of mobile devices poses a serious impact on user experience. As an increasingly prevalent type of applications in mobile cloud environments, location-based applications (LBAs) present some inherent limitations concerning energy. For example, the Global Positioning System based positioning mechanism is well-known for its extremely power-hungry attribute. Due to the severity of the issue, considerable researches have focused on energy-efficient locating sensing mechanism in the last a few years. In this paper, we provide a comprehensive survey of recent work on low-power design of LBAs. An overview of LBAs and different locating sensing technologies used today are introduced. Methods for energy saving with existing locating technologies are investigated. Reductions of location updating queries and simplifications of trajectory data are also mentioned. Moreover, we discuss cloud-based schemes in detail which try to develop new energy-efficient locating technologies by leveraging the cloud capabilities of storage, computation and sharing. Finally, we conclude the survey and discuss the future research directions. © 2013 Springer-Verlag Wien.

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BACKGROUND: There has been a significant growth in the energy drink (ED) market in Australia and around the world; however, most research investigating the popularity of ED and alcohol and energy drink (AED) use has focused on specific subpopulations such as university students. The aim of this study was to estimate the prevalence, consumption patterns, and sociodemographic correlates of ED and combined AED use among a representative Australian population sample. METHODS: A computer-assisted telephone interview survey (n = 2,000) was undertaken in March-April 2013 of persons aged 18 years and over. Half of the interviews were obtained through randomly generated landline telephone numbers and half through mobile phones. Approximately half of the sample was female (55.5%; n = 1,110) and the mean age of participants was 45.9 (range 18 to 95, SD 20.0). RESULTS: Less than 1 in 6 Australians reported ED use (13.4%, n = 268) and 4.6% (n = 91) reported AED use in the past 3 months. Majority of ED and AED users consumed these beverages monthly or less. ED and AED users are more likely to be aged 18 to 24 years, live in a metropolitan area, and be moderate risk or problem gamblers. AED consumers are more likely to report moderate levels of psychological distress. CONCLUSIONS: Our findings in relation to problem gambling and psychological distress are novel and require further targeted investigation. Health promotion strategies directed toward reducing ED and AED use should focus on young people living in metropolitan areas and potentially be disseminated through locations where gambling takes place.

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Background: Previous research on alcohol mixed with energy drinks (AmED) has shown that use is typically driven by hedonistic, social, functional, and intoxication-related motives, with differential associations with alcohol-related harm across these constructs. There has been no research looking at whether there are subgroups of consumers based on patterns of motivations. Consequently, the aims were to determine the typology of motivations for AmED use among a community sample and to identify correlates of subgroup membership. In addition, we aimed to determine whether this structure of motivations applied to a university student sample. Methods: Data were used from an Australian community sample (n = 731) and an Australian university student sample (n = 594) who were identified as AmED consumers when completing an online survey about their alcohol and ED use. Participants reported their level of agreement with 14 motivations for AmED use; latent classes of AmED consumers were identified based on patterns of motivation endorsement using latent class analysis. Results: A 4-class model was selected using data from the community sample: (i) taste consumers (31%): endorsed pleasurable taste; (ii) energy-seeking consumers (24%): endorsed functional and taste motives; (iii) hedonistic consumers (33%): endorse pleasure and sensation-seeking motives, as well as functional and taste motives; and (iv) intoxication-related consumers (12%): endorsed motives related to feeling in control of intoxication, as well as hedonistic, functional, and taste motives. The consumer subgroups typically did not differ on demographics, other drug use, alcohol and ED use, and AmED risk taking. The patterns of motivations for the 4-class model were similar for the university student sample. Conclusions: This study indicated the existence of 4 subgroups of AmED consumers based on their patterns of motivations for AmED use consistently structured across the community and university student sample. These findings lend support to the growing conceptualization of AmED consumers as a heterogeneous group in regard to motivations for use, with a hierarchical and cumulative class order in regard to the number of types of motivation for AmED use. Prospective research may endeavor to link session-specific motives and outcomes, as it is apparent that primary consumption motives may be fluid between sessions.

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In this work, the crystallization rates and spherulitic growth rate of miscible blends of poly(vinylidene fluoride) (PVDF) and acrylic rubber (ACM) were determined using differential scanning calorimetry (DSC), real-time FTIR, and optical microscopy. FTIR results suggest that blending does not induce the creation of polymorphic crystalline forms of PVDF. SAXS data demonstrate the formation of interlamellar structure after blending. The fold surface-free energy (σ e) was analyzed and compared using different thermal analysis techniques. The isothermal crystallization curves obtained using real-time FTIR and DSC explored in two different methods: t 1/2 or Avrami equation. While the Avrami equation is more widespread and precise, both analytical methods gave similar free energy of folding values. However, it was found that the direct optical method of measuring spherulitic growth rate yields σ e values 30-50 % lower than those obtained from the overall crystallization rate data. Conversely, the σ e values were found to increase with increasing amorphous ACM phase content regardless of the analytical methods.