scholarly journals Analysing the Police Patrol Routing Problem: A Review

2020 ◽  
Vol 9 (3) ◽  
pp. 157 ◽  
Author(s):  
Maite Dewinter ◽  
Christophe Vandeviver ◽  
Tom Vander Beken ◽  
Frank Witlox
Keyword(s):  
Police Officers ◽  
Keyword Search ◽  
Hybrid Genetic Algorithm ◽  
Dynamic Vehicle Routing ◽  
Routing Problem ◽  
Police Patrol ◽  
Starting Point ◽  
Solution Methods ◽  
Routing Policies ◽  
Patrol Routing

Police patrol is a complex process. While on patrol, police officers must balance many intersecting responsibilities. Most notably, police must proactively patrol and prevent offenders from committing crimes but must also reactively respond to real-time incidents. Efficient patrol strategies are crucial to manage scarce police resources and minimize emergency response times. The objective of this review paper is to discuss solution methods that can be used to solve the so-called police patrol routing problem (PPRP). The starting point of the review is the existing literature on the dynamic vehicle routing problem (DVRP). A keyword search resulted in 30 articles that focus on the DVRP with a link to police. Although the articles refer to policing, there is no specific focus on the PPRP; hence, there is a knowledge gap. A diversity of approaches is put forward ranging from more convenient solution methods such as a (hybrid) Genetic Algorithm (GA), linear programming and routing policies, to more complex Markov Decision Processes and Online Stochastic Combinatorial Optimization. Given the objectives, characteristics, advantages and limitations, the (hybrid) GA, routing policies and local search seem the most valuable solution methods for solving the PPRP.

scholarly journals Current State of Dynamic Vehicle Routing Problems Solved by Ant Colony Optimization Algorithm

2021 ◽  
Vol 15 (3) ◽  
pp. 429-434
Author(s):  
Luka Olivari ◽  
Goran Đukić
Keyword(s):  
Ant Colony Optimization ◽  
Vehicle Routing ◽  
Optimization Algorithm ◽  
Vehicle Routing Problem ◽  
Ant Colony ◽  
Ant Colony Optimization Algorithm ◽  
Dynamic Vehicle Routing ◽  
Routing Problems ◽  
Routing Problem ◽  
Solution Methods

Dynamic Vehicle Routing Problem is a more complex version of Vehicle Routing Problem, closer to the present, real-world problems. Heuristic methods are used to solve the problem as Vehicle Routing Problem is NP-hard. Among many different solution methods, the Ant Colony Optimization algorithm is proven to be the efficient solution when dealing with the dynamic version of the problem. Even though this problem is known to the scientific community for decades, the field is extremely active due to technological advancements and the current relevance of the problem. As various sub-types of routing problems and solution methods exist, there is a great number of possible problem-solution combinations and research directions. This paper aims to make a focused review of the current state in the field of Dynamic Vehicle Routing Problems solved by Ant Colony Optimization algorithm, to establish current trends in the field.

The Constitutional Principle of Accountability: A Study of Contemporary South African Case Law

2018 ◽  
Vol 33 (1) ◽  
Author(s):  
Chuks Okpaluba
Keyword(s):  
Judicial Review ◽  
Police Officers ◽  
Public Procurement ◽  
Case Law ◽  
The State ◽  
Constitutional Principle ◽  
Starting Point ◽  
The Law ◽  
Constitutional Right ◽  
The Many

‘Accountability’ is one of the democratic values entrenched in the Constitution of South Africa, 1996. It is a value recognised throughout the Constitution and imposed upon the law-making organs of state, the Executive, the Judiciary and all public functionaries. This constitutional imperative is given pride of place among the other founding values: equality before the law, the rule of law and the supremacy of the Constitution. This study therefore sets out to investigate how the courts have grappled with the interpretation and application of the principle of accountability, the starting point being the relationship between accountability and judicial review. Therefore, in the exercise of its judicial review power, a court may enquire whether the failure of a public functionary to comply with a constitutional duty of accountability renders the decision made illegal, irrational or unreasonable. One of the many facets of the principle of accountability upon which this article dwells is to ascertain how the courts have deployed that expression in making the state and its agencies liable for the delictual wrongs committed against an individual in vindication of a breach of the individual’s constitutional right in the course of performing a public duty. Here, accountability and breach of public duty; the liability of the state for detaining illegal immigrants contrary to the prescripts of the law; the vicarious liability of the state for the criminal acts of the police and other law-enforcement officers (as in police rape cases and misuse of official firearms by police officers), and the liability of the state for delictual conduct in the context of public procurement are discussed. Having carefully analysed the available case law, this article concludes that no public functionary can brush aside the duty of accountability wherever it is imposed without being in breach of a vital constitutional mandate. Further, it is the constitutional duty of the courts, when called upon, to declare such act or conduct an infringement of the Constitution.

scholarly journals A Modified Harmony Search Algorithm for Solving the Dynamic Vehicle Routing Problem with Time Windows

2017 ◽  
Vol 2017 ◽  
pp. 1-13 ◽  
Author(s):  
Shifeng Chen ◽  
Rong Chen ◽  
Jian Gao
Keyword(s):  
Vehicle Routing ◽  
Vehicle Routing Problem ◽  
Search Algorithm ◽  
Time Windows ◽  
Harmony Search ◽  
Population Diversity ◽  
Benchmark Problems ◽  
Dynamic Vehicle Routing ◽  
Dynamic Vehicle Routing Problem ◽  
Routing Problem

The Vehicle Routing Problem (VRP) is a classical combinatorial optimization problem. It is usually modelled in a static fashion; however, in practice, new requests by customers arrive after the initial workday plan is in progress. In this case, routes must be replanned dynamically. This paper investigates the Dynamic Vehicle Routing Problem with Time Windows (DVRPTW) in which customers’ requests either can be known at the beginning of working day or occur dynamically over time. We propose a hybrid heuristic algorithm that combines the harmony search (HS) algorithm and the Variable Neighbourhood Descent (VND) algorithm. It uses the HS to provide global exploration capabilities and uses the VND for its local search capability. In order to prevent premature convergence of the solution, we evaluate the population diversity by using entropy. Computational results on the Lackner benchmark problems show that the proposed algorithm is competitive with the best existing algorithms from the literature.

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