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The aim of this research is to examine if building information modelling (BIM) is feasible as an information management platform to determine a financially and environmentally affordable housing refurbishment solution based on the life cycle cost (LCC) and LCC calculation.

A case study in conjunction with BIM simulation approach using BIM tools (Autodesk Revit and IES VE/IMPACT) was adopted to identify the feasibility of BIM for the simultaneous formulation of LCC and life cycle assessment in housing refurbishment.

This research reveals that BIM is a suitable for the information management platform to enable construction professionals to consider trade-off relationship between LCC and life cycle assessment simultaneously, and determine the most financially and environmentally affordable refurbishment solution. The interoperability issues in data exchange among different BIM tools and unstandardized BIM object libraries with incomplete data sets of construction materials are recognised as the major shortcomings in a BIM system. Essential remedial actions to overcome the shortcomings in the current BIM tools are identified.

Actual housing information and various refurbishment materials for the BIM simulation are limited.

This research contributes to supporting construction professionals to prepare practical BIM adoption for the integration of the LCC and life cycle assessment that can significantly improve early decision-makings on sustainable housing refurbishment.

This research will contribute to providing proper remedial actions to overcome the shortcomings in the current BIM tools, and insights for construction professionals to understand the implication of BIM-embedded housing refurbishment.

The purpose of this paper is to propose an alternative approach to improve the performance of microelectromechanical systems (MEMSs) silicon (Si) condenser microphones in terms of operating frequency and sensitivity through the introduction of a secondary material with a contrast of mechanical properties in the corrugated membrane.

Finite element method from COMSOL is used to analyze the MEMS microphones performance consisting of solid mechanic, electrostatic and thermoviscous acoustic interfaces. Hence, the simulated results could described the physical mechanism of the MEMS microphones, especially in the case of microphones with complex geometry. A 2-D model was used to simplify computation by applying axis symmetry condition.

The simulation results have suggested that the operating frequency range of the microphone could be extended to be operated beyond 20 kHz in the audible frequency range. The data showed that the frequency resonance of the microphone using a corrugated Si membrane with SiC as the embedded membrane is increased up to 70 kHz compared with 63 kHz for the plane Si membrane, whereas the microphone’s sensitivity is slightly decreased to −79 from −76 dB. Furthermore, the frequency resonance of a corrugated membrane microphone could be improved from 26 to 70 kHz by embedding the SiC material. Last, the sensitivity and frequency resonance value of the microphones could be modified by adjusting the height of the embedded material.

Based on these theoretical results, the proposed modification highlighted the advantages of simultaneous modifications of frequency and sensitivity that could extend the applications of sound and acoustic detections in the ultrasonic spectrum with an acceptable performance compared with the typical state-of-the-art Si condenser microphones.

Congestion as a consequence of the rapidly growing air traffic is one of the outstanding problems of the air transportation industry. Traffic impediment rates, having an increasing acceleration while the airport capacities have been kept constant due to several reasons, cause problems such as arrival/departure delays, schedule interruptions, cancellations and customer dissatisfaction. In this paper, the author aims to study transitioning from a single-hub air transportation system to a multi-hub infrastructure via Monte Carlo simulation.

The current hub has reached its capacity limits for long so that the growth potential of the air transportation has been affected adversely. One of the possible remedies suggested by authorities, professionals and academics was to transform the air transportation infrastructure into a multi-hub setting. Current air traffic of the country was modeled by means of simulation. Airport capacities and performances are simulated and analyzed under different scenarios considering a potential alternative hub along with the central one. Possible delays in both hubs are studied in case of moderately increasing traffic congestion.

As a result, decreased delay levels in the central hub are observed, whereas no delays are experienced in the potential one in all the scenarios.

This study, proposing to organize the national and international air traffic of the country while harmonizing the delay rates and increasing the passenger satisfaction, is to contribute significantly to the aviation sector companies, airliners and airport operators by shedding light on the imminent capacity issues air transportation industry is going to face.

The purpose of this study is to assess the impact of rising food prices on food demand and nutrient intake among rural–urban migrants and whether such impact varies across income classes.

Using data from the China Health and Nutrition Survey (CHNS), this study adopts a quadratic almost ideal demand system (QUAIDS) for food demand elasticity and an indirect estimation method for nutrient elasticity to investigate the effects of rising food prices on food demand and nutrient intake among rural–urban migrants.

The estimated results indicate that an increase in the price of pork alone would lead to a larger reduction in most nutrients among rural–urban migrants than other single targeted food group, and a simultaneous rise in the price of all food groups would have a remarkably adverse effect on the nutritional status of rural–urban migrants in comparison to the nutritional effects of a rise in one targeted food group. In addition, the nutritional effects of food prices across income classes show that the nutritional status is particularly vulnerable to rising food prices among low-income rural–urban migrants.

This paper focuses on analyzing the impact of rising food prices on the nutritional status of rural–urban migrants, a topic that is very limited in the literature. This study provides a fresh look at the effect of volatile food prices on food demand and nutrient intake among rural–urban migrants. The results indicate that income growth would have a remarkable positive effect on nutrient intake for rural–urban migrants, especially for low-income rural–urban migrants. However, an increment in nutrients due to a growth in income would not be far from enough to cover the reduction in nutrients as a result of a simultaneous rise in price of all the studied food categories at the same rate.

The purpose of this paper is to study the evolution and growth of aerosol particles in a turbulent planar jet by using the newly developed large eddy simulation (LES)-differentially weighted operator splitting Monte Carlo (DWOSMC) method.

The DWOSMC method is coupled with LES for the numerical simulation of aerosol dynamics in turbulent flows.

Firstly, the newly developed and coupled LES-DWOSMC method is verified by the results obtained from a direct numerical simulation-sectional method (DNS-SM) for coagulation occurring in a turbulent planar jet from available literature. Then, the effects of jet temperature and Reynolds number on the evolution of time-averaged mean particle diameter, normalized particle number concentration and particle size distributions (PSDs) are studied numerically on both coagulation and condensation processes. The jet temperature and Reynolds number are shown to be two important parameters that can be used to control the evolution and pattern of PSD in an aerosol reactor.

The coupling between the Monte Carlo method and turbulent flow still encounters many technical difficulties. In addition, the relationship between turbulence, particle properties and collision kernels of aerosol dynamics is not yet well understood due to the theoretical limitations and experimental difficulties. In the present study, the developed and coupled LES-DWOSMC method is capable of solving the aerosol dynamics in turbulent flows.

Generally, the implementation of lean manufacturing (LM) starts with the development of value stream maps. However, it has been found that value stream mapping (VSM) suffers from various shortcomings. Hence, researchers have suggested the use of simulation along with VSM. The purpose of this paper is to present an application of VSM with simulation during the design of lean manufacturing systems (LMS) using a case study of an organisation following a job shop production system to manufacture doors and windows.

Simulation models were developed using QUeuing Event Simulation Tool for the case organisation to demonstrate how the case organisation will be changed after implementing various LM elements, apart from analysing the impact of implementing these LM elements on the organisation's performance.

Simulation studies were carried out for different scenarios such as “before LM” (current state VSM) and “after LM” (future state VSM). It was found that the case organisation can achieve significant improvement in performance and can meet the increasing demand without any additional resources.

It is believed that this paper will enable practitioners to appreciate the role of simulation in helping them understand how the operations department of the case organisation will be transformed during the design of LMS.

According to the authors' knowledge, no case study exists in the literature that discusses the application of VSM with simulation in an organisation that manufactures doors and windows using a job shop production system. Furthermore, the paper simulates the impact of those LM elements which were not considered by other researchers on the performance measure of the case organisation.

Imperfections in manufacturing processes may cause unwanted connections (faults) that are added to the nominal, “golden”, design of an electronic circuit. By fault simulation one simulates all situations. Normally this leads to a large list of simulations in which for each defect a steady-state (direct current (DC)) solution is determined followed by a transient simulation. The purpose of this paper is to improve the robustness and the efficiency of these simulations.

Determining the DC solution can be very hard. For this the authors present an adaptive time-domain source stepping procedure that can deal with controlled sources. The method can easily be combined with existing pseudo-transient procedures. The method is robust and efficient. In the subsequent transient simulation the solution of a fault is compared to a golden, fault-free, solution. A strategy is developed to efficiently simulate the faulty solutions until their moment of detection.

The paper fully exploits the hierarchical structure of the circuit in the simulation process to bypass parts of the circuit that appear to be unaffected by the fault. Accurate prediction and efficient solution procedures lead to fast fault simulation.

The fast fault simulation helps to store a database with detectable deviations for each fault. If such a detectable output “matches” a result of a product that has been returned because of malfunctioning it helps to identify the subcircuit that may contain the real fault. One aims to detect as much as possible candidate faults. Because of the many options the simulations must be very efficient.

States that manufacturing lines cannot be used for production during commissioning and that it is therefore always the goal to reduce the necessary efforts to a maximum extent. Starts with a description of the state‐of‐the‐art in this field based on the situation in the automotive industry. Additionally lists RTD fields to overcome these problems. Goes on to present methods and software tools aiming at a tremendous decrease in efforts required today.

Design teams have difficulties in assessing building carbon emissions at an early stage, as most building energy simulation tools require a detailed input of building design for estimation. The purpose of this paper is to develop a user-friendly regression model to estimate carbon emissions of the preliminary design of office buildings in the subtropics by way of example. Five sets of building design parameters, including building configuration, building envelope, design space conditions, building system configuration and occupant behaviour, are considered in this study.

Both EnergyPlus and Monte Carlo simulation were used to predict carbon emissions for different combinations of the design parameters. A total of 100,000 simulations were conducted to ensure a full range of simulation results. Based on the simulation results, a regression model was developed to estimate carbon emissions of office buildings based on preliminary design information.

The results show that occupant density, annual mean occupancy rate, equipment load, lighting load and chiller coefficient of performance are the top five influential parameters affecting building carbon emissions under the subtropics. Besides, the design parameters of ten office buildings were input into this user-friendly regression model for validation. The results show that the ranking of its simulated carbon emissions for these ten buildings is consistent with the original carbon emissions ranking.

With the use of this developed regression model, design teams can not only have a simple and quick estimation of carbon emissions based on the building design information at the conceptual stage but also explore design options by understanding the level of reduction in carbon emissions if a certain building design parameter is changed. The study also provides recommendations on building design to reduce carbon emissions of office buildings.

Limited research has been conducted to date to investigate how the change of building design affects carbon emissions in the subtropics where four distinct seasons lead to significant variations of outdoor temperature and relative humidity. Previous research also did not emphasise on the impact of high-rise office building designs (e.g. small building footprint, high window-to-wall ratio) on carbon emissions. This paper adds value by identifying the influential parameters affecting carbon emissions for a high-rise office building design and allows a handy estimate of building carbon emissions under the subtropical conditions. The same approach may be used for other meteorological conditions.