A comparative study of benchmarking approaches for non-domestic buildings: Part 1 – Top-down approach

Benchmarking plays an important role in improving energy efficiency of non-domestic buildings. A review of energy benchmarks that underpin the UK’s Display Energy Certificate (DEC) scheme have prompted necessities to explore the benefits and limitations of using various methods to derive energy benchmarks. The existing methods were reviewed and grouped into top-down and bottom-up approaches based on the granularity of the data used. In the study, two top-down methods, descriptive statistics and artificial neural networks (ANN), were explored for the purpose of benchmarking energy performances of schools. The results were used to understand the benefits of using these benchmarks for assessing energy efficiency of buildings and the limitations that affect the robustness of the derived benchmarks. Compared to the bottom-up approach, top-down approaches were found to be beneficial in gaining insight into how peers perform. The relative rather than absolute feedback on energy efficiency meant that peer pressure was a motivator for improvement. On the other hand, there were limitations with regard to the extent to which the energy efficiency of a building could be accurately assessed using the top-down benchmarks. Moreover, difficulties in acquiring adequate data were identified as a key limitation to using the top-down approach for benchmarking non-domestic buildings. The study suggested that there are benefits in rolling out of DECs to private sector buildings and that there is a need to explore more complex methods to provide more accurate indication of energy efficiency in non-domestic buildings

The pituri story: a review of the historical literature surrounding traditional Australian Aboriginal use of nicotine in Central Australia

The harmful outcomes of nicotine self administration have been the focus of sustained global health education campaigns that have targeted tobacco smoking and to a lesser extent, smokeless tobacco use. 'Smokeless tobacco' infers that the nicotine is not burnt, and administration can be through a range of methods including chewing. The chewing of wild tobacco plants (Nicotiana spp.) is practiced across a broad inland area of Central Australia by traditional Aboriginal groups. Collectively these plants are known by a variety of names - one common name being 'pituri'. This is the first paper to examine the historical literature and consider the linkage between pituri use and health outcomes. Using a narrative approach, this paper reviews the literature generated since 1770 surrounding the term pituri and the behaviours associated with its use. The review examines the scientific literature, as well as the diaries and journals of nineteenth century explorers, expedition notes, and early Australian novels to expound the scientific evidence and broaden the sense of understanding related to pituri, particularly the behavioural elements. The evaluation considers the complexities of ethnobotany pertaining to language and distance and the ethnopharmacology of indigenous plant usage. The review compares the use of burnt and smokeless tobacco to pituri and establishes the foundation for research into the clinical significance and health outcomes of pituri use. Additionally, this review provides contemporary information for clinicians providing care for patients who chew pituri

A Monte Carlo Analysis of the Thrust Imbalance for the RSRMV Booster During Both the Ignition Transient and Steady State Operation

This paper presents the results of statistical analyses performed to predict the thrust imbalance between two solid rocket motor boosters to be used on the Space Launch System (SLS) vehicle. Two legacy internal ballistics codes developed for the Space Shuttle program were coupled with a Monte Carlo analysis code to determine a thrust imbalance envelope for the SLS vehicle based on the performance of 1000 motor pairs. Thirty three variables which could impact the performance of the motors during the ignition transient and thirty eight variables which could impact the performance of the motors during steady state operation of the motor were identified and treated as statistical variables for the analyses. The effects of motor to motor variation as well as variations between motors of a single pair were included in the analyses. The statistical variations of the variables were defined based on data provided by NASA's Marshall Space Flight Center for the upgraded five segment booster and from the Space Shuttle booster when appropriate. The results obtained for the statistical envelope are compared with the design specification thrust imbalance limits for the SLS launch vehicl

Numerical Modeling of Propellant Boiloff in Cryogenic Storage Tank

This Technical Memorandum (TM) describes the thermal modeling effort undertaken at Marshall Space Flight Center to support the Cryogenic Test Laboratory at Kennedy Space Center (KSC) for a study of insulation materials for cryogenic tanks in order to reduce propellant boiloff during long-term storage. The Generalized Fluid System Simulation program has been used to model boiloff in 1,000-L demonstration tanks built for testing the thermal performance of glass bubbles and perlite insulation. Numerical predictions of boiloff rate and ullage temperature have been compared with the measured data from the testing of demonstration tanks. A satisfactory comparison between measured and predicted data has been observed for both liquid nitrogen and hydrogen tests. Based on the experience gained with the modeling of the demonstration tanks, a numerical model of the liquid hydrogen storage tank at launch complex 39 at KSC was built. The predicted boiloff rate of hydrogen has been found to be in good agreement with observed field data. This TM describes three different models that have been developed during this period of study (March 2005 to June 2006), comparisons with test data, and results of parametric studies

Numerical Modeling of Propellant Boil-Off in a Cryogenic Storage Tank

A numerical model to predict boil-off of stored propellant in large spherical cryogenic tanks has been developed. Accurate prediction of tank boil-off rates for different thermal insulation systems was the goal of this collaboration effort. The Generalized Fluid System Simulation Program, integrating flow analysis and conjugate heat transfer for solving complex fluid system problems, was used to create the model. Calculation of tank boil-off rate requires simultaneous simulation of heat transfer processes among liquid propellant, vapor ullage space, and tank structure. The reference tank for the boil-off model was the 850,000 gallon liquid hydrogen tank at Launch Complex 39B (LC- 39B) at Kennedy Space Center, which is under study for future infrastructure improvements to support the Constellation program. The methodology employed in the numerical model was validated using a sub-scale model and tank. Experimental test data from a 1/15th scale version of the LC-39B tank using both liquid hydrogen and liquid nitrogen were used to anchor the analytical predictions of the sub-scale model. Favorable correlations between sub-scale model and experimental test data have provided confidence in full-scale tank boil-off predictions. These methods are now being used in the preliminary design for other cases including future launch vehicle

Nicotine vaping product use, harm perception and policy support among pharmacy customers in Brisbane, Australia

Despite regulatory barriers for accessing nicotine liquid, use of nicotine vaping products (NVPs) has increased rapidly in Australia. Legal use of NVPs to aid smoking cessation requires a prescription, and pharmacies report receiving enquiries about the use of and access to NVPs. In this study, we assessed vaping product use, harm perception and policy support among community pharmacy customers.A cross-sectional survey was conducted among customers (n = 470) from a large community pharmacy chain in Brisbane, Australia. Multivariable logistic regression was used to examine perception of NVPs as less harmful than combustible cigarettes and regulatory recommendations in relation to demographics, smoking status and NVP use.Almost one-third of the sample (31%) had either tried NVPs in the past (16%) or were current vapers (15%), the majority of them being current smokers (67%) who are trying to quit (31%) or substitute smoking (41%). Vapers primarily depended on family/friends as a source of information (76%). Current smokers and vapers were more likely to perceive NVPs as less harmful than cigarettes than non-smokers and non-vapers. Perceiving NVPs as safer than cigarettes was correlated with a recommendation to regulate as a tobacco product.There was widespread misperception about relative risk of nicotine-containing products, with 37% of respondents perceiving nicotine-containing NVPs to be as harmful as combustible cigarettes. Community pharmacies represent an ideal setting for educating smokers about smoking and vaping. Thus, pharmacy staff needs educational support to ensure that they are equipped to provide current evidence-based information to customers

Framing and scientific uncertainty in nicotine vaping product regulation: An examination of competing narratives among health and medical organisations in the UK, Australia and New Zealand

Aims To compare the policy positions of health and medical organisations across Australia, New Zealand, and the UK as they relate to sale and supply of nicotine vaping products (NVPs) and evaluate factors that have informed the differences in policy recommendations among these countries. Methods We used mixed methods to analyse data from position or policy statements published by health and medical organisations regarding NVPs (n = 30) and consultation documents submitted to government committees regarding policy options for the regulation of NVPs (n = 26). Quality assessment of included documents was conducted using the six-item Joanna Briggs Institute (JBI) Critical Appraisal Checklist for Text and Opinion Papers, and findings were presented narratively. Qualitative data were coded using NVivo 12 software and analysed using thematic analysis. Results An overwhelming majority of health bodies, charities and government agencies in the UK and New Zealand portrayed NVPs as a life-saving harm reduction tool. In contrast, concerns about addicting non-smoking youth to nicotine, a perceived lack of clear and convincing evidence of safety and efficacy and the potential to undermine tobacco control progress continues to define attitudes and recommendations towards NVPs among Australian health and medical organisations. Although the profoundly divided views among stakeholders seem to arise from empirical uncertainties and disagreements over the level and credibility of evidence, the source of most of these disagreements can be traced back to the fundamental and irreconcilable differences in the framing of the NVP debate, and varied tolerability of risk trade-offs associated with NVPs. Conclusion Progress in resolving the controversy surrounding NVP policy requires stakeholders to be frame-reflective and engage in a meaningful dialogue of risk trade-offs, as well as both intended and unintended consequences of proposed policies