Dynamic thermal models: reliability for domestic building design

This paper describes a three year UK initiative—Applicability Study 1-to enhance the usability and credibility of detailed thermal simulation programs with particular reference. to the design of passive solar dwellings. Researchers at Leicester Polytechnic and the Building Research Establishment are working with ESP, HTB2 and SERIRES. The aims are to identify the problems for which these programs can be used reliably and those for which they cannot, to provide guidance on the best modelling techniques, indicate the uncertainty inherent in predictions, identify the attributes of programs which are necessary to obtain reliable results, and indicate areas in which additional theoretical or experimental research is needed. The results to date show that good agreement in some design trends can be obtained provided a high level of quality control is exercised and program users have a good understanding of the theoretical basis of the programs. There were, however, some situations in which the programs still predicted significant differences in the trends in energy consumption as the building design changed. These may be explained by the different algorithms employed by the detailed thermal simulation programs and errors in them

Metric versus observable operator representation, higher spin models

We elaborate further on the metric representation that is obtained by transferring the time-dependence from a Hermitian Hamiltonian to the metric operator in a related non-Hermitian system. We provide further insight into the procedure on how to employ the time-dependent Dyson relation and the quasi-Hermiticity relation to solve time-dependent Hermitian Hamiltonian systems. By solving both equations separately we argue here that it is in general easier to solve the former. We solve the mutually related time-dependent Schrödinger equation for a Hermitian and non-Hermitian spin 1/2, 1 and 3/2 model with time-independent and time-dependent metric, respectively. In all models the overdetermined coupled system of equations for the Dyson map can be decoupled algebraic manipulations and reduces to simple linear differential equations and an equation that can be converted into the non-linear Ermakov-Pinney equation

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Planning energy systems for small rural communities (including economic, technical and thermodynamic criteria)

SIGLEAvailable from British Library Document Supply Centre- DSC:DX83608 / BLDSC - British Library Document Supply CentreGBUnited Kingdo