This paper presents the use of micro-Doppler signatures collected by a multistatic radar to detect and discriminate between micro-drones hovering and flying while carrying different payloads, which may be an indication of unusual or potentially hostile activities. Different features have been extracted and tested, namely features related to the Radar Cross Section of the micro-drones, as well as the Singular Value Decomposition (SVD) and centroid of the micro-Doppler signatures. In particular, the added benefit of using multistatic information in comparison with conventional radar is quantified. Classification performance when identifying the weight of the payload that the drone was carrying while hovering was found to be consistently above 96% using the centroid-based features and multistatic information. For the non-hovering scenarios classification results with accuracy above 95% were also demonstrated in preliminary tests in discriminating between three different payload weights.

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This letter presents preliminary results on the use of multistatic radar and micro-Doppler analysis to detect and discriminate between microdrones hovering carrying different payloads. Two suitable features related to the centroid of the micro-Doppler signature have been identified and used to perform classification, investigating also the added benefit of using information from a multistatic radar as opposed to a conventional monostatic system. Very good performance with accuracy above 90% has been demonstrated for the classification of hovering micro-drones.

This paper uses resilience as a lens through which to analyse disasters and other major threats to patterns of criminal behaviour. A set of indicators and mathematical models are introduced that aim to quantitatively describe changes in crime levels in comparison to what could otherwise be expected, and what might be expected by way of adaptation and subsequent resumption of those patterns. The validity of the proposed resilience assessment tool is demonstrated using commercial theft data from the COVID-19 pandemic period. A 64 per cent reduction in crime was found in the studied city (China) during an 83-day period, before daily crime levels bounced back to higher than expected values. The proposed resilience indicators are recommended as benchmarking instruments for evaluating and comparing the global impact of COVID-19 policies on crime and public safety.

More than two decades after the publication of Cornish's seminal work about the scripttheoretic approach to crime analysis, this article examines how the concept has been applied in our community. The study provides evidence confirming that the approach is increasingly popular; and takes stock of crime scripting practices through a systematic review of over one hundred scripts published between 1994 and 2018. The results offer the first comprehensive picture of this approach, and highlights new directions for those interested in using data from cyber-systems and the Internet of Things to develop effective situational crime prevention measures.

Background: With the growing interest in the use of crime scripts and attack scenarios for the development of control measures comes the need for more systematic scripting methods. Information about those sequences of actions that offenders carry out to commit a given type of crime can be extremely valuable to designers as control measures may be designed to influence the possibility to actualise criminal plans. However, there exists limited guidance as to what qualities crime scripts should possess in order to support the creation of suitable requirements, and how they should be handled in a design framework.Discussion: This theoretical work contributes to the production and sharing of scientifically robust, useful and usable crime scripts. Drawing a link with the main application considered in this paper, it details the ways in which scripts can contribute to the development of functional requirements for control measures. It presents a list of defects commonly encountered with requirements specifications, and identifies those that could originate from poorly constructed scripts. This section adopts a modelling approach to identify and discuss the sought qualities of crime scripts, but the results apply to all scripts developed for the purpose of reducing crime. Summary:The author presents a list of twelve quality criteria that could be used to evaluate crime scripts. These were identified by considering the common defects of requirements specifications, and tracing back their potential causes within crime scripts. The criteria relate to the following modelling aspects: typology, traceability, transparency, consistency, context, completeness, parsimony, precision, uncertainty, usability, ambiguity and accuracy. A checklist is also provided to facilitate comparison between scripts, contribute to their utility, and ensure that the information required by designers of security systems is available within the functional requirements to be developed for innovative designs. Ultimately, this first investigation of quality assurance in crime scripting opens an important avenue towards further research on the construction and evaluation of crime scripts, their verification and validation.

Studies suggest that incidents of sexual harassment are common occurrence on public transport in India, but there is little reliable data to understand and tackle the problem. This research explores actual and witnessed victimisations as well as perceptions of the risk by a sample of 200 tertiary female students in Lucknow, India. Consistent with literature, sexual harassment victimisation appears to be most prevalent in buses and increases with the frequency of use of public transport. We found that the number of incidents experienced as a victim and as a witness were comparable, suggesting events of sexual harassment are not widely noticed by other passengers, perhaps because they are so commonplace as not to be especially noticed. Finally, the respondents felt female students were particularly targeted amongst women more generally, but did not identify any specific risk factors in relation to the profiles of the offenders or victims.

Metal theft has become an increasingly common crime in recent years, but lack of data has limited research into it. The present study used police-recorded crime data to study the spatial and temporal concentration of metal theft from the railway network of Great Britain. Metal theft was found to exhibit only weak seasonality, to be concentrated at night and to cluster in a few locations close to -but not in -major cities. Repeat-victimisation risk continued for longer than has been found for other crime types. These and other features appear to point to metal theft being a planned, rather than opportunistic, offence and to the role of scrap-metal dealers as facilitators.