A simulated annealing approach to police district design

This paper considers the problem of redistricting or redrawing police command boundaries. We model this problem as a constrained graph-partitioning problem involving the partitioning of a police jurisdiction into command districts subject to constraints of contiguity, compactness, convexity and size. Since the districting affects urban emergency services, there also exist quality-of-service constraints, which limit the response time (queue time plus travel time) to calls for service. Confronted with the combinatorial challenge of the districting problem, we propose a simulated annealing algorithm to search for a “good” partitioning of the police jurisdiction. At each iteration of the algorithm, we employ a variant of the well-known PCAM model to optimally assign the patrol cars and assess the “goodness” of a particular district design with respect to some prescribed performance measures. This approach differs from the well-known Hypercube queuing model, which simply evaluates the performance of a user-specified district design and allocation. A computational case study using data from the Buffalo, New York, Police Department reveals the merits of this approach.Scope and purposeTwo of the primary concerns of urban police departments are the effective use of patrol cars and the workload balance between officers in different geographical districts. In recent years, a well known, public domain software package based on the Patrol Car Allocation Model (PCAM) has been developed. PCAM was designed to help police management specify the number of patrol cars that should be on duty at various times of the day on each day of the week in each district. For long-term planning, police management also faces the thorny problem of designing these districts. To address this problem, we employ a simulated annealing search method to determine the geographic boundaries between the police districts. PCAM is used to evaluate the “goodness” of each district design encountered in this search, where “goodness” involves minimizing the disparity between the maximum workload and the minimum workload of the police officers. Working with the Buffalo, New York, Police Department, we were able to significantly reduce officer workload disparity while maintaining current levels of response time.     

VoiceLETS backs up first responders

VoiceLETS accesses data in the existing Law Enforcement Tactical System. LETS is a secure Web-based search engine designed to provide personal and vehicle information to law enforcement and criminal justice agencies. It integrates access to several state databases and currently includes photographs, addresses, personal characteristics, and driver and criminal histories from the state's motor vehicles and corrections departments. The University of Alabama's CARE Research and Development Laboratory developed LETS with the goal of making it available to all qualifying agencies over the Internet, including patrol officers using mobile data terminals.     

Developing an online cooperative police patrol routing strategy

A cooperative routing strategy for daily operations is necessary to maintain the effects of hotspot policing and to reduce crime and disorder. Existing robot patrol routing strategies are not suitable, as they omit the peculiarities and challenges of daily police patrol including minimising the average time lag between two consecutive visits to hotspots, as well as coordinating multiple patrollers and imparting unpredictability to patrol routes. In this research, we propose a set of guidelines for patrol routing strategies to meet the challenges of police patrol. Following these guidelines, we develop an innovative heuristic-based and Bayesian-inspired real-time strategy for cooperative routing police patrols. Using two real-world cases and a benchmark patrol strategy, an online agent-based simulation has been implemented to testify the efficiency, flexibility, scalability, unpredictability, and robustness of the proposed strategy and the usability of the proposed guidelines.     

Determining Optimal Police Patrol Areas with Maximal Covering and Backup Covering Location Models

This paper presents a new method for determining efficient spatial distributions of police patrol areas. This method employs a traditional maximal covering formulation and an innovative backup covering formulation to provide alternative optimal solutions to police decision makers, and to address the lack of objective quantitative methods for police area design in the literature or in practice. This research demonstrates that operations research methods can be used in police decision making, presents a new backup coverage model that is appropriate for patrol area design, and encourages the integration of geographic information systems and optimal solution procedures. The models and methods are tested with the police geography of Dallas, TX. The optimal solutions are compared with the existing police geography, showing substantial improvement in number of incidents covered as well as total distance traveled.     

欧美电子监听技术标准研究

根据欧洲电信标准委员会（ETSI）及美国《通讯协助法》（CALEA）关于电子监听标准的研究和规定,本文分析了在电子监听中执法机构对电信服务提供者的要求、监听的相关数据类型以及交接接口标准等问题。对规范我国电子监听标准、开展电子监听工作有一定的借鉴和帮助。     

基于北斗和GPS的森林防火人员调度指挥系统

森林防火人员监控调度指挥系统是根据森林防火人员调度指挥工作的实际需要,设计并实现的基于北斗定位导航技术、GPS、GIS的软硬化一体平台。系统实现的功能主要有:人员实时定位、重点区域或人员监控、巡护人员与系统互通信、人员历史路径查询、人员巡山防火执勤工作量统计等。该系统构筑了森林巡护工作的信息服务网络,加强了森林巡护工作的落实,并为科学地应急指挥调度提供决策支持。     

基于“3S”平台的巡警监管系统的设计与应用

提出一种基于GPS/GPRS/GIS平台的巡警监管系统的设计方法,为巡警管理部门提供一个直观、便捷和实时的监管平台,可以大大加强对巡警的监管力度,进而有效提高巡警的工作效率.系统使用Oracle数据库来存储系统的空间数据和属性数据,确保系统数据的快速访问和高可靠性.依据本平台设计的巡警监管系统在辽宁某市巡警部门已经进行实际应用,并取得了良好的效果.     

Allocation of police beats to patrol units to minimize response time to calls for service

Optimal beat configurations to minimize response time to calls for service can be determined for a given number of police patrol beats during a shift. However, optimal manpower scheduling requires that the number of units vary by day of week. A variable beat design strategy is administratively infeasible. This model operates under a fixed beat design strategy and assigns beats to a variable number of units. The computer program improves an initial beat assignment by considering all possibilities of moving or sharing beats with other units. The new beat assignments are reevaluated till an optima is reached.     

GPS差分定位技术在遥控遥测方面的应用

差分GPS定位能将卫星误差和星历误差消除,能把电离层延迟和对流层延迟误差部分消除,并能减小美国政府SA政策对卫星定位精度的影响,使得定位精度大大提高。所以,差分GPS定位技术在最近几年中得到了迅速发展和广泛应用。伪距差分定位技术在武警车辆遥测遥控方面的应用,为武警巡逻车辆的快速调度和合理安排很有帮助,大大提高了武警部队在治安和追捕逃犯方面的能力。因此,一些先进国家都建立了这一系统。在我国一些城市也开始建立这一系统,具有很大的应用前景。     

Algorithmic risk assessment policing models: lessons from the Durham HART model and ‘Experimental’ proportionality

As is common across the public sector, the UK police service is under pressure to do more with less, to target resources more efficiently and take steps to identify threats proactively; for example under risk-assessment schemes such as ‘Clare’s Law’ and ‘Sarah’s Law’. Algorithmic tools promise to improve a police force’s decision-making and prediction abilities by making better use of data (including intelligence), both from inside and outside the force. This article uses Durham Constabulary’s Harm Assessment Risk Tool (HART) as a case-study. HART is one of the first algorithmic models to be deployed by a UK police force in an operational capacity. Our article comments upon the potential benefits of such tools, explains the concept and method of HART and considers the results of the first validation of the model’s use and accuracy. The article then critiques the use of algorithmic tools within policing from a societal and legal perspective, focusing in particular upon substantive common law grounds for judicial review. It considers a concept of ‘experimental’ proportionality to permit the use of unproven algorithms in the public sector in a controlled and time-limited way, and as part of a combination of approaches to combat algorithmic opacity, proposes ‘ALGO-CARE’, a guidance framework of some of the key legal and practical concerns that should be considered in relation to the use of algorithmic risk assessment tools by the police. The article concludes that for the use of algorithmic tools in a policing context to result in a ‘better’ outcome, that is to say, a more efficient use of police resources in a landscape of more consistent, evidence-based decision-making, then an ‘experimental’ proportionality approach should be developed to ensure that new solutions from ‘big data’ can be found for criminal justice problems traditionally arising from clouded, non-augmented decision-making. Finally, this article notes that there is a sub-set of decisions around which there is too great an impact upon society and upon the welfare of individuals for them to be influenced by an emerging technology; to an extent, in fact, that they should be removed from the influence of algorithmic decision-making altogether.     

Security, wiretapping, and the Internet

In a move that is dangerous to network security, the US Federal Bureau of Investigation is seeking to extend the Communications for Law Enforcement Act to voice over IP. Such an extension poses national security risks.     

The effect of police cruiser restraint cage configuration on shoulder discomfort,muscular demands,upper limb postures,and task performance during simulated police patrol

Advances in police-specific technology have led to changes in work layout and physical occupational demands of mobile police officers. This study investigated the influence of police cruiser compartment configuration on perceived discomfort, muscle activation, shoulder kinematics, and typing performance during simulated police patrol. Participants completed a one-hour session including simulated driving and 2-min typing trials in a standard compartment configuration with a fixed mobile data terminal (MDT) location (ST), and in a modified compartment configuration with an MDT in front of the user and a rearward translated seat (MOD). The MOD configuration resulted in reductions of 55–65% in perceived shoulder discomfort, up to 3.4% MVC in shoulder muscle demands, and more neutral humeral orientations (shoulder elevation reduced by 13–25°). These improvements associated with the MOD configuration may have ergonomic implications for future police car designs, particularly as new technology is introduced in the mobile environment and advanced solutions are sought.     

Designing the right wiretap solution: setting standards under CALEA

The Communications Assistance for Law Enforcement Act (CALEA) requires telecommunications providers, including VoIP and broadband ISPs, to provide wiretapping capabilities with their services. Law enforcement and the telecommunications industry must work together to set CALEA-compliant standards.     

Spatio-temporal crime predictions in smart cities: A data-driven approach and experiments

Steadily increasing urbanization is causing significant economic and social transformations in urban areas, posing several challenges related to city management and services. In particular, in cities with higher crime rates, effectively providing for public safety is an increasingly complex undertaking. To handle this complexity, new technologies are enabling police departments to access growing volumes of crime-related data that can be analyzed to understand patterns and trends. These technologies have potentially to increase the efficient deployment of police resources within a given territory and ultimately support more effective crime prevention. This paper presents a predictive approach based on spatial analysis and auto-regressive models to automatically detect high-risk crime regions in urban areas and to reliably forecast crime trends in each region. The algorithm result is a spatio-temporal crime forecasting model, composed of a set of crime-dense regions with associated crime predictors, each one representing a predictive model for estimating the number of crimes likely to occur in its associated region. The experimental evaluation was performed on two real-world datasets collected in the cities of Chicago and New York City. This evaluation shows that the proposed approach achieves good accuracy in spatial and temporal crime forecasting over rolling time horizons.     

A network simulation model for police patrol vehicle maintenance and replacement analysis

Research in the field of urban police patrol-car analysis has tended to concentrate in the areas of vehicle deployment, fleetsize and location, etc., with very little emphasis in the area of vehicle maintenance and replacement policy. As such, the purpose of this paper is to develop and demonstrate a simulation model for patrol-vehicle replacement and maintenance analysis. The simulation model will encompass a Markov-type framework of state movements where the states represent the various stages of a patrol vehicle's life from new to inoperable. The model will be developed in the form of a Q-Gert network, and, demonstrated via a case example of an urban patrol fleet of 100 vehicles.     

CYBERCRIMINAL PROFILING

Abstract

Criminal profiling is both an art and a science, knowing what types of people mostly commit unambiguous types of criminal offenses. Law Enforcement and Information Technology professionals need to work together to control this growing problem: Cybercrime and the individuals behind it.     

Internet wiretapping decision headed for the courts

The US Federal Communications Commission (FCC) faces a legal challenge over its decision to compel broadband and voice-over-IP service providers to comply with wiretapping requests under the Communications Assistance for Law Enforcement Act. Law enforcement is not internally developing the capability to understand IP communications and that means law enforcement is completely unable to intercept the communications of any sophisticated terrorist organization or criminal organization, because it is a trivial matter for a moderately knowledgeable engineer to sit down and create a voice communication system just to be used by the internal criminal network.     

警用无人系统与低空安全防范初探

对我国的低空安全现状及新形势下警务执法工作人员面临的挑战进行了分析,研究了当前警用无人系统的主要装备及其在低空监控、日常巡逻、侦察、取证、快速处置等警务活动中的应用,结合面向低空安全的三维数字化空中走廊技术体系,探索了警用无人系统在报警、接警、执法、处置业务流程中的低空安全防范应用策略。在低空安全防范的数学建模研究中,以无人机违规事件的实时威胁扩散趋势分析中遇到的数据缺失问题为例,根据数据属性值进行了数学建模研究,采用了基于定距型数据和非定距型数据属性的缺失数据估计方法进行缺失数据估计的数学建模。最后,对警用无人系统在低空安全防范中的应用前景进行了展望。     

公安地理信息系统的设计与实现

论述了公安地理信息系统的设计方法及其体系结构。以110指挥系统为例,论述了其主要组件的功能、开发原理和方法,讨论了公安地理信息系统的软件开发方法及系统的实现。该系统的建立,在打击犯罪、维护社会治安中发挥了重要作用,为全国各省市的公安机关建立地理信息系统提供了一个模板,有效地提高了公安机关的信息化水平。     

Abstracts & Commentaries

Abstract

COMPUTER CRIME — CRIMINAL JUSTICE, by SRI International National Criminal Justice Information and Statistics Service, Law Enforcement Assistance Administration, U.S. Department of Justice, Washington, DC, 20530. 1979. 18-page booklet.