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Energy management in existing building services installations is an essential focus of contemporary facilities management. The subway company that is one of the major utilities services in Hong Kong Special Administrative Region has considered better energy management schemes in its subway stations to reduce the running cost. In the past few years some feasible measures in the mechanical ventilation and air conditioning (MVAC) systems were implemented, however the engineering decisions were supported by trial‐and‐error or imprecise estimation. Improvement to this process would be possible if numerical optimization methods were to be used. An evolutionary algorithm coupled with an external plant simulation programme was applied to determine the optimum conditions of the essential parameters of the MVAC systems. For the centralized MVAC systems under study, the developed optimization and simulation model was found useful in appraising the energy management opportunities for effective design and facilities management.

Energy consumption in existing office buildings has been growing in parallel with the rise in occupant energy demand. As a result, many building owners have given smart retrofits (SRs) a higher priority. However, the utilisation of suitable SRs from a range of SRs has become a challenging task. The purpose of this paper is to develop a decision-making model to select the most suitable SRs for conventional office buildings and form a set of benchmarks for assessing the performance of SRs.

A qualitative approach with six case studies was used. Content analysis was carried out using NVivo to explore the factors considered for the selection of SR techniques. A decision-making model for selecting SRs in Sri Lankan office buildings was proposed. SR performance benchmarks were developed by referring to established standards and studies done in tropical office buildings.

Out of 18 identified SRs from literature, fan cycling, ventilation control and LED luminaires have been recognised as commonly used SRs in Sri Lankan office buildings. Analysis showed that HVAC retrofits saved more energy, while lighting retrofits could be easily implemented in existing buildings. The proposed decision-making model can explore further improvements to enhance the performance of SRs.

The selection of SRs is a comprehensive decision-making process. Metrics were established to benchmark the performance of SRs. The proposed model offers a tool for building owners and facility managers to optimise facility operations.

The world was facing significant aging challenges. Aging in place has long been advocated which reflected the preference of older people to stay in their own home as long as possible. A huge amount of older people resided in private buildings that consist of both indoor settings (i.e. individual unit flats) and outdoor settings (i.e. common areas like lobby and corridor). The effect of indoor environment on the quality of life of the older people has been investigated, while this paper aims to examine the different effect of common areas environment for the older people.

A questionnaire survey was administered among over 300 older people living in private buildings. Multiple statistical techniques, including reliability test, correlation coefficient and multiple regression models, were used to analyze the collected data to determine the interactions between facilities management of the common areas in private buildings and the environment domain of quality of life for older people.

The final results were concluded based on the congruence of all the statistical results, which covered the identification of facilities management factors in common areas of private buildings that could influence the environment domain of quality of life for older people, including overall environment, health-care accessibility, information acquisition and transportation aspects; the overall environment was positively predicted by space and security in common areas of private building; health-care accessibility was positively affected by space, barrier-free facilities and recreational facilities; the information acquisition was only positively predicted by security; transportation was positively predicted by distance and recreational facilities; and building services of common areas in private buildings had no effect on the environment domain of quality of life for older people.

Practical recommendations have been made to improve the facilities management of common areas in private buildings to ensure the quality of life for older people, including provision of walking assistance, motion or infrared controlled systems and so on. This study contributed to enhance current understanding of the interactions between the older people and their living environment.

This paper aims to clarify the necessity of taking into account the commonly neglected radiation in built environments. Ignoring radiation within acclimatized spaces with moist air, which is a participating medium, can yield inaccurate values of the relevant variables, endangering the Heating, ventilation, and air conditioning design accuracy and leading to energy inefficiencies and discomfort.

The paper uses computational fluid dynamics to predict non-isothermal flows with radiation, for both mixing and displacement ventilation strategies. The tool is applied to a lab-scale model (scale 1:30), and the results are compared with experimental data and predictions without radiation. Furthermore, the radiation influence is also assessed at real-scale level, including a parametric study on the effect of the air relative humidity on radiation.

The paper demonstrates the unequivocal impact of radiation on the flows thermal-kinematics at real-scale: ignoring radiation yields average air temperature differences of 2ºC. This becomes more evident for larger air optical thicknesses (larger relative humidity): changing it from 20 per cent to 50 per cent and 70 per cent yields maximum relative differences of 100 per cent for the velocity components and 0.4ºC for the air temperature. Nevertheless, the results for the lab-scale case are not so conclusive about the effect of moist air radiation on the thermal flow characteristics, but they evidence its impact on the flow kinematics (maximum relative differences of velocity components of 35 per cent).

The paper fulfills an identified need to clarify the relevant effects of air moisture on radiation and on the flow turbulence and thermal-kinematic characteristics for forced convective flows inside built environments.

This paper aims to extract colour from micro-organisms (as a source of natural pigments) using agro-industrial substrates to replace synthetic media by solid state fermentation. Nature is filled with colours. Due to health and environmental consciousness among people, use of synthetic colour has declined, and so the need to develop colour from cheap and easily available natural sources (plants, animals, micro-organisms and algae) using a cost-effective technique with higher yield and rapid growth. Monascus purpureus colour is a potent source of compounds (Dimerumic acid, Monacolin-k and -aminobutyric acid) having antimutagenic, antimicrobial and antiobesity, which helps in combating diseases.

Response surface methodology was used to optimise the biopigments extraction from Monascus purpureus using solid state fermentation.

The best optimised conditions for biopigments production using Monascus purpureus MTCC 369 were pH 5.4 at 32°C for 8 days 9 hours (8.9 days) from sweet potato peel and pea pod powder, 7.8 (w/w) and 3.9 per cent (w/w), respectively, which gave a final yield of 21 CVU/g. The model F-value of 69.18 and high value of adjusted determination coefficient 96.00 per cent implies high level of significance of the fitted model.

Extracted colour can be used in beverages, confectionery and pharmaceutical industries.

Colour produced using Monascus purpureus MTCC 369 is a natural source. As consumers are reluctant to use synthetic colour because of the undesirable allergic reactions caused by them, so a biopigment produced is natural colouring compound with wide application in food sector.

Selected sources of carbon and nitrogen were not used earlier by any researcher to extract biopigment from Monascus purpureus MTCC 369.

The Iranian banking industry has been greatly affected by dramatic changes in macroeconomic conditions over the past several decades owing to volatile oil revenues, changing fiscal and monetary policies, and the imposition of US sanctions. The main objective of this paper is to estimate potential credit losses in the Iranian banking sector due to macroeconomic shocks and assess the minimum economic capital requirements under the baseline and distressed scenarios. The paper also contrasts the applications of linear and nonlinear models in estimating the impacts of macroeconomic shocks on financial institutions.

The paper uses a multistage approach to derive the portfolio loss distribution for banks. In the first step, the dynamic relationship between the selected macroeconomic variables are estimated using a VAR model to generate the stress scenarios. In the second step, the default probabilities are estimated using a quantile regression model and the results are compared with those of the conventional linear models. Finally, the default probabilities are simulated for a one-year time horizon using Monte-Carlo method and the portfolio loss distribution is calculated for hypothetical portfolios. The expected loss includes the loss given default for loans drawn randomly and uniformly distributed and exposed at default values when loans are assigned a fixed value.

The results indicate that the loss distributions under all scenarios are skewed to the right, with the linear model results being very similar to those of quantile at the 50% quantile, but very unlike those at the 10% and 90% quantiles. Specifically, the quantile model for the 90% (10%) quantile generates estimates of minimum economic capital requirement that are considerably higher (lower) than those using the linear model.

The study has focused on credit risk because of lack of data on other types of risk at individual bank level. The future studies can estimate the aggregate economic capital using a risk aggregation approach and a panel data (not presently available), which could further improve the accuracy of the estimates.

The fiscal and monetary authorities in developing countries, specially oil-exporting countries, can follow the risk assessment approach to assess the health of their banking system and adapt policies to mitigate the impacts of large macroeconomic shocks on their financial markets.

This is the first paper estimating the portfolio loss distribution for the Iranian banks under turbulent macroeconomic conditions using linear and nonlinear models. The case study can be applied to other developing and emerging countries, particularly those highly dependent on natural resources, prone to extreme macroeconomic shocks.

To provide the performance comparison between the conventional mixing ventilation (MV) and the displacement ventilation (DV) with and without cooling ceiling, which can be helpful to design.

The commercial CFD software FLUENT with RNG k‐ε turbulent model was used. The CFD method was validated via comparing with the available experimental data.

It was found that if properly designed, the DV system can supply better indoor air quality in the occupied zone, including better distribution in temperature field, higher ventilation efficiency, lower contaminant field and more thermal comfort compared with the MV system, because of the stratification effect of DV. And the locations of return air outlets have a great effect on the performance of the ventilation system. It was also found that the DV systems can be used to remove air contaminations more efficiently, but the temperature difference in the occupied zone in the DV system is higher than that in the MV system, especially if the heat load is higher. This problem may be solved if the cooled ceiling is combined with the DV, because the vertical temperature in the occupied zone will be reduced and more thermal comfort can be achieved.

More detailed computation should be performed on the thermal radiation between different surfaces in the room.

A very useful source of information for thermal designing of air condition.

This paper provides the performance comparison between the conventional MV and the DV with and without cooling ceiling, based on flow and temperature distribution.

The operation of chiller systems could account for considerable electricity consumption in air‐conditioned buildings in subtropical regions. The purpose of this paper is to consider using data envelopment analysis (DEA) to facilitate management of their energy performance.

A system serving an institutional building was studied, which contains five sets of chillers, pumps and cooling towers. The building has a total floor area of about 25,000m² and comprises classrooms, lecture theatres, offices and laboratories. The scale, technical and overall efficiencies defined in DEA were calculated based on the correlation between the output variable – system coefficient of performance (COP) – and the input variables – load factor and temperatures of chilled water and condenser water. The efficiencies were further examined to explain how outside air temperatures and controllable variables affect the system performance.

The paper reveals that existing energy management gives a technical efficiency of 0.85 and fine‐tuning the temperature‐related variables could achieve an electricity saving of 14.8 per cent.

The improved COP predicted by DEA is related only to fine‐tuning of the input variables concerned. An increase of COP by other advanced controls or system upgrades should be assessed based on robust system modelling techniques. Yet the extent of COP improvements helps investigate energy management opportunities requiring no or insignificant capital investment on existing systems.

A systematic approach to performing energy management of a chiller system is proposed. The DEA helps examine which operating variable should be fine‐tuned to achieve the highest possible performance.

It is an under researched area to consider using scale and technical efficiencies in DEA to explain energy management of chiller systems and to estimate the highest achievable performance.

The two main contributing factors that control the overall buildings’ energy performance are the heating ventilation and air conditioning (HVAC) system and the envelope design. Environmental design guidelines that consider these two factors aim to lower energy consumption. However, they are regional and climate-sensitive. This study aims to investigate how three main buildings’ envelope design variables (orientation, compactness and window to wall ratio) impact the overall building’s energy consumption within Kuwait’s regional and climate conditions.

This study simulate the energy consumption of typically shaped buildings by varying their geometry between a square to a rectangular floor plan. This study analyse the associated energy usage and provide early-stage envelope design guidance specific to the country’s conditions, to make informed decisions towards environmentally conscious buildings.

The analysed envelope variables have the potential to reduce energy consumption by 40%, and the possibility to reduce HVAC system capacity by 30%. In contrast to the general guidance in literature and standards, the simulation results demonstrate that less compact building forms perform on occasions better than the most compact ones.

The objective of this paper is to quantify the energy consumption rates for buildings located within the Arabian Peninsula, an under-studied region with potentially high interest considering three main envelope design variables. The buildings’ yearly energy consumption patterns are unique and suggest different envelope design considerations, compared to other regions with different climate conditions. This emphasises the importance of regional guidelines for the different factors associated with energy and buildings’ environmental performance.

The construction industry consumes large amounts of natural resources, which are not properly utilised owing to the generation of waste. Construction waste has challenged the performance of the industry and its sustainable goals. The majority of the causes underlying material waste are directly or indirectly affected by the behaviour of the construction workforce. Waste occurs on site for a number of reasons, most of which can be prevented, particularly by changing the attitudes of the construction workforce. Therefore, the attitudes and perceptions of the construction workforce can influence the generation and implementation of waste management strategies. The research reported in this paper is based on a study aimed at evaluating the attitudes and perceptions of the construction workforce involved during the pre‐ and post‐contract stages towards minimising waste.

A structured questionnaire survey was carried out to understand and evaluate the attitudes and perceptions of the workforce. Four types of questionnaires were prepared for project managers/site managers, supervisors, labourers, and estimators.

The findings indicate the positive perceptions and attitudes of the construction workforce towards minimising waste and conserving natural resources. However, a lack of effort in practising these positive attitudes and perceptions towards waste minimisation is identified. The paper further concludes that negative attitudes towards subordinates, attitudinal differences between different working groups, and a lack of training to reinforce the importance of waste minimisation practices have obstructed proper waste management practices in the industry.

The paper reveals the effect of the attitudes and perceptions of the construction workforce towards waste management applications, which would be of benefit to construction managers in designing and implementing better waste management practices.