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This paper aims to present an application of location optimization techniques for deploying police facilities subject to budgetary and feasibility constraints. The objectives considered included minimizing the distances and maximizing the coverage of police stations over potential crime spots.

The optimization consists of two stages. In Stage 1, a minimum distance model is used to determine the locations of police stations. Given the locations of police stations, Stage 2 uses a maximum coverage model to determine the police patrol area. The framework is applied to a case in the Greater London Area. The authors also evaluate the resilience of the optimal solutions with the terrorist attack scenario on 7 July 2005 in Central London.

With the optimization models, it is shown that the average distance between police stations and potential crime spots is reduced by 19 per cent. The coverage percentage of potential crime spots is also increased from the existing 91.99 per cent to a nearly perfect 99.82 per cent. Nevertheless, the results reveal that the optimal police resources deployment is less resilient with respect to the existing one. The findings herein suggest the importance of incorporating measures of resilience into the optimization framework and the authors leave this topic for further investigation.

The study highlights the value of location optimization to police force deployment in terms of finding the optimal locations of police force with respect to the spatial distribution of crimes. In particular, the authors investigate its implication on urban resilience, which is among the first study of this kind.

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.

This paper is an in‐depth analysis of community policing in Hong Kong. It includes an outline of the evolution of community policing in Hong Kong, identifies the structural arrangements for the practice of community policing, examines major community‐based programs that have been launched, evaluates the performance of this strategy, and considers constraints on these policy initiatives. It shows that this community effort has already gone beyond the confines of promoting community relations in Hong Kong. The results have been encouraging. They include a significant improvement in the quality of police‐public interactions, the engagement of the public and their increased support in crime control and prevention, and the beginning of the conversion of traditional police enforcement to that of police services. However, the Force's use of community policing schemes predominantly for the pragmatic purpose of crime control has accounted for the lack of breakthroughs in forging a strategic partnership with the public to promote a secure and harmonious environment.

The purpose of this paper is to examine the factors explaining the success of Hong Kong’s Independent Commission Against Corruption (ICAC) and the challenges which it faces in maintaining that success.

Utilising a review of primary and secondary sources, a syndrome of success characteristics is developed and analysed against a backdrop of recent high-level scandals involving corruption and unethical behaviour.

The paper concludes that the institutionalisation of key structures and processes has enabled the ICAC to perform successfully to date but that the prospect of political interference may represent a significant future challenge.

Although there has been widespread attention to ICAC success factors, some important features have been neglected and little academic attention has been devoted to recent political challenges to its position.