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Consequent to an arson fire killing 17 persons in a Hong Kong karaoke in 1997, fire safety provisions in karaokes has raised public concern. Government officers and the services industry have agreed to upgrade fire safety provisions. But before deciding what to do, facilities for the existing karaokes are the subject of a review. A simple fire safety ranking system was proposed in 1999 for existing karaokes. They were grouped on the basis of their fire facilities and management system. The system was criticized for being inapplicable to local industry, as a result of failing to solicit views from the services industry. That system has since been revised. Trial runs in 19 existing karaokes were carried out in 2000. Now, the system is more suited for local use as it is simple. Hence advocates the use of the system to the Hong Kong Fire Authority for assessing fire safety of existing karaokes.

This paper aims to give a brief review on behavioral economics and behavioral finance and discusses some of the previous research on agents' utility functions, applicable risk measures, diversification strategies and portfolio optimization.

The authors also cover related disciplines such as trading rules, contagion and various econometric aspects.

While scholars could first develop theoretical models in behavioral economics and behavioral finance, they subsequently may develop corresponding statistical and econometric models, this finally includes simulation studies to examine whether the estimators or statistics have good power and size. This all helps us to better understand financial and economic decision-making from a descriptive standpoint.

The research paper is original.

The purpose of this paper is to check and fill the gap between the existing fire safety regulations for newly built tall buildings in Bulgaria and those in areas with rapid economic growth in the Asia-Oceania regions like the Hong Kong Special Administrative Region and Mainland China, by making comparative analysis and identifying good practices. The main focus is on the development of fire safety designs, facilities and management, which shall be recognized as essential parts of facility management in tall buildings.

Bulgarian regulations are analyzed and then compared with those in the Hong Kong Special Administrative Region and Mainland China. In addition, the scientific aspect of fire load density in the fire codes is discussed. The possibility of implementing a fire engineering approach to supplement prescriptive codes is outlined. The essential roles of fire safety management and fire safety culture are presented.

Key points and recommendations that are worthy for discussion about incorporation in the Bulgarian tall buildings fire safety requirements are upgraded requirements for fire load density, detection and sprinkler systems in tall residential buildings, refuge floors, ventilation/air conditioning control systems, full-scale burning tests and fire engineering approach. The importance of fire safety management is emphasized as a main, key component in facility management.

The research is the first study focusing on implementation of additional and specific fire safety regulations for tall buildings in Bulgaria.

The purpose of this paper is to investigate the development process of the fire whirl in the fixed-frame facility and focus on the impacts of the fire whirl’s vortex core on the formation and flame structure of the fire whirl.

The complex turbulent reacting flame surface is captured by the large eddy simulation turbulence closure coupled with two sub-grid scale (SGS) kinetic schemes (i.e. the chemistry equilibrium and steady diffusion flamelet). Numerical predictions are validated thoroughly against the measurements by Lei et al. (2015) with excellent agreements. A double maximum tangential velocity refinement approach is proposed to quantify the vortex cores’ instantaneous location and region, addressing the missing definition in other studies.

The numerical results show that the transition process of the fire whirl is dominated by the vortex core movement, which is related to the centripetal force. The unsteadiness of the fully developed fire whirl was found depending on the instantaneous fluctuation of heat release rate. The steady diffusion flamelet scheme is essential to capture the instantaneous fluctuation. Furthermore, the axial velocity inside the vortex core is the key to determining the state of fire whirl.

Due to intensive interactions between buoyant fires and ambient rotating flow, the on-set and formation of fire whirl still remain largely elusive. This paper focused on the transition process of fire whirl between different development stages. This paper provides insights into the transition process from the inclined flame to the fire whirls based on the centripetal force.

This paper presented and compared two SGS kinetic schemes to resolve the fire whirl development process and the unsteadiness of its vortical structures. The modelling framework addresses the shortcoming of previous numerical studies where RANS turbulence closure and simplified combustion kinetics was adopted. Numerical results also revealed the fire whirl transition process and its relationship to centripetal force.

Service quality has become an important area for competition among Chinese carriers. This paper focuses on studying the relationship between customer satisfaction measured by customer complaints and their expectation of the on-time performance of Chinese carriers and how the customer complaints affect the financial performance of carriers. By using a quarterly balanced panel data set covering six large listed carriers, the empirical results show that an increase in actual on-time performance reduces customer complaints. However, an increase in expected on-time performance significantly raises customer complaints. An increase in customer complaint reduces the yield measured as revenue per revenue ton kilometer (RTK) of carriers.

Automatic sprinkler systems are considered as one of the most important facilities for providing building fire safety. Even old high‐rise buildings are required to upgrade the fire safety provisions. Four standards on installing sprinkler systems in high‐rise commercial buildings are briefly reviewed and compared. They are the British Standard 5306, the National Fire Protection Association Standard NFPA‐13, the Australian Standard 2118.1 and the Codes of China. Key areas are discussed by comparing their suitabilities for local use. Designs following the four standards for a typical old high‐rise building (i.e. those built before 1972) will be worked out to illustrate the differences in using the four methods.

The purpose of this study is to review and summarise the existing available literature on lightweight cladding systems to provide detailed information on fire behaviour (ignitibility, heat release rate and smoke toxicity) and various test method protocols. Additionally, the paper discusses the challenges and provides updated knowledge and recommendation on selective-fire mechanisms such as rapid-fire spread, air cavity and fire re-entry behaviours due to dripping and melting of lightweight composite claddings.

A comprehensive literature review on fire behaviour, fire hazard and testing methods of lightweight composite claddings has been conducted in this research. In summarising all possible fire hazards, particular attention is given to the potential impact of toxicity of lightweight cladding fires. In addition, various criteria for fire performance evaluation of lightweight composite claddings are also highlighted. These evaluations are generally categorised as small-, intermediate- and large-scale test methods.

The major challenges of lightweight claddings are rapid fire spread, smoke production and toxicity and inconsistency in fire testing.

The review highlights the current challenges in cladding fire, smoke toxicity, testing system and regulation to provide some research recommendations to address the identified challenges.

The water mist fire suppression system (WMFSS) is an environmentally friendly fire protection system, replacing the total flooding halon system. It is starting to be popular in Hong Kong with five systems approved. However, such systems were tested under some scenarios very different from real fires. Performance under practical scenarios should be evaluated thoroughly. Full‐scale burning tests should be carried out to support that the systems would work in real fire scenarios as expected. This paper aims to briefly discuss whether the water mist system is suitable for use in Hong Kong.

Five water mist systems were approved in Hong Kong based on the fire test certificate provided by the manufacturers. Four systems were selected in this paper for discussion. Conditions of the fire scenarios in which the approved systems would work are described. The test scenario encountered should match with real fires. Such systems would work satisfactorily in the application area proposed. They are good for enclosed rooms such as machinery spaces and plant rooms. But applying such systems for use in retail areas or libraries should be watched carefully, particularly those with high ventilation rates.

It is observed that the four approved systems were only evaluated on machinery plant rooms with volume less than 500 m³. They are demonstrated to be effective in extinguishing a wide range of bigger Class B fires with very little residual water in a short time. However, the loss of water vapor under mechanical ventilation conditions might reduce the extinguishing capability of mist. The water mist nozzle should not be installed near to the exhaust and supply positions of the mechanical ventilation system. Note that WMFSS is not effective in handling shielded fires due to the lower mist concentration.

Full‐scale burning tests on pool fires of different shapes under water mist were carried out. It was demonstrated that WMFSS might not work under some fire scenarios. Different scenarios on the amount and arrangement of combustibles, room geometry and sizes would affect the system performance. Further, shop fires were burnt with performance of the water mist system evaluated. Heat release rate curves on the shop fire with and without discharging water mist are measured. Reignition occurred once water supply was shut down, burning up all combustibles.

Effectiveness of WMFSS is determined by other factors, including the spray characteristics, fire size, ceiling height and ventilation rate in the compartment. Their performance in mechanical ventilation rooms should be watched. As a result, the total flooding system might not be so good. Localized water mist systems directed to the hazard might be more reliable to suppress fire. Water nozzle design is a key area as raised by the principal author. Anyway, the possible fire scenarios must be identified in designing workable WMFSS. Full‐scale burning tests should be conducted to demonstrate the system performance.

This chapter provides a survey of alternative methodologies for measuring and comparing productivity and efficiency of airlines, and reviews representative empirical studies. The survey shows the apparent shift from index procedures and traditional OLS estimation of production and cost functions to stochastic frontier methods and Data Envelopment Analysis (DEA) methods over the past three decades. Most of the airline productivity and efficiency studies over the last decade adopt some variant of DEA methods. Researchers in the 1980s and 1990s were mostly interested in the effects of deregulation and liberalization on airline productivity and efficiency as well as the effects of ownership and governance structure. Since the 2000s, however, studies tend to focus on how business models and management strategies affect the performance of airlines. Environmental efficiency now becomes an important area of airline productivity and efficiency studies, focusing on CO₂ emission as a negative or undesirable output. Despite the fact that quality of service is an important aspect of airline business, limited attempts have been made to incorporate quality of service in productivity and efficiency analysis.