The Elderly Centre Location Problem

© The Operational Research Society 2020. This is an Accepted Manuscript of an article published by Taylor & Francis in Journal of the Operational Research Society on 12 Feb 2020, available online: https://doi.org/10.1080/01605682.2020.1718020.Increased human life expectancy combined with declining birth rates around the globe has led to ageing populations, particularly in the developed world. This phenomenon brings about increased dependency ratios and calls for setting new policies for the elderly citizens. This comprises the provision of a set of life-enhancing services in an accessible and equitable way. In this paper, we consider a multi-period problem of locating senior centres offering these services to the elderly population against budget constraints and capacity limitations. We assume that the attractiveness of facilities to elderlies is inversely proportional with the travel time to access these facilities. Both consistent and inconsistent versions of the problem are considered, aiming at identifying the set of facilities to operate in each region at each period, the service type(s) to be offered and the allocation of budget in each period to location and operation of facilities. A mixed integer mathematical programming model is presented, an efficient iterated local search procedure is proposed and managerial insights are provided.Peer reviewedFinal Accepted Versio

The Bi-objective Periodic Closed Loop Network Design Problem

© 2019 Elsevier Ltd. This manuscript is made available under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International licence (CC BY-NC-ND 4.0). For further details please see: https://creativecommons.org/licenses/by-nc-nd/4.0/Reverse supply chains are becoming a crucial part of retail supply chains given the recent reforms in the consumers’ rights and the regulations by governments. This has motivated companies around the world to adopt zero-landfill goals and move towards circular economy to retain the product’s value during its whole life cycle. However, designing an efficient closed loop supply chain is a challenging undertaking as it presents a set of unique challenges, mainly owing to the need to handle pickups and deliveries at the same time and the necessity to meet the customer requirements within a certain time limit. In this paper, we model this problem as a bi-objective periodic location routing problem with simultaneous pickup and delivery as well as time windows and examine the performance of two procedures, namely NSGA-II and NRGA, to solve it. The goal is to find the best locations for a set of depots, allocation of customers to these depots, allocation of customers to service days and the optimal routes to be taken by a set of homogeneous vehicles to minimise the total cost and to minimise the overall violation from the customers’ defined time limits. Our results show that while there is not a significant difference between the two algorithms in terms of diversity and number of solutions generated, NSGA-II outperforms NRGA when it comes to spacing and runtime.Peer reviewedFinal Accepted Versio

Compassion on University Degree Programmes at a UK University: The Neuroscience of Effective Group work

This article is published under the Creative Commons Attribution (CC BY 4.0) licence. Anyone may reproduce, distribute, translate and create derivative works of this article (for both commercial and non-commercial purposes), subject to full attribution to the original publication and authors. The full terms of this licence may be seen at http://creativecommons.org/ licences/by/4.0/legalcodePurpose The purpose of this paper is to explore the neuroscience that underpins the psychology of compassion as a competency. We explain why this cognitive competency is now taught and assessed on modules of different degree subjects in a UK university. Design/methodology/approach The paper is divided into first, an exploration of recent psychology and neuroscience literature that illuminates the differences, and relationship, between empathy and compassion for safeness building in teams. Within that, the role of oxytocin in achieving social and intellectual rewards though the exercise of cognitive flexibility, working memory and impulsive inhibitory control (Zelazo, et al, 2016) is also identified. The literature findings are compared against relevant qualitative data from the above university’s, so far, nine years of mixed methods action research on compassion-focused pedagogy (CfP). Findings These are that the concept and practice of embedding compassion as a cognitive competency into assessed university group work is illuminated and rationalised by research findings in neuroscience. Research limitations/implications The limitations of the study are that, so far, fMRI research methods have not been used to investigate student subjects involved in the compassion-focused pedagogy now in use. Practical implications The paper has implications for theory, policy and practice in relation to managing the increasing amount of group work that accompanies widening participation in Higher Education. Originality/value A review of this kind specifically for student assessed group and its implications for student academic achievement and mental health has not, apparently, been publishedPeer reviewe

A heuristic approach to solve the preventive health care problem with budget and congestion constraints

This document is the Accepted Manuscript version of the following article: Soheil Davari, Kemal Kilic, and Siamak Naderi, ‘A heuristic approach to solve the preventive health care problem with budget and congestion constraints’, Applied Mathematics and Computation, Vol. 276, pp. 442-453, March 2016, doi: https://doi.org/10.1016/j.amc.2015.11.073. This manuscript version is made available under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives License CC BY NC-ND 4.0 (http://creativecommons.org/licenses/by-nc-nd/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited, and is not altered, transformed, or built upon in any way.Preventive health care is of utmost importance to governments since they can make massive savings on health care expenditure and promote the well-being of the society. Preventive care includes many services such as cancer screenings, vaccinations, hepatitis screenings, and smoking cessation programs. Despite the benefits of these services, their uptake is not satisfactory in many countries in the world. This can be attributed to financial barriers, social issues., and other factors. One of the most important barriers for preventive care is accessibility to proper services, which is a function of various qualitative and quantitative factors such as the distance to travel, waiting time, vicinity of facilities to other attractive facilities (such as shopping malls), and even the cleanliness of the facilities. Statistics show that even a small improvement in people’s participation can save massive amounts of money for any government and improve the well-being of the people in a society. This paper addresses the problem of designing a preventive health care network considering impatient clients, and budget constraints. The objective is to maximize the accessibility of services to people. We model the problem as a mixed-integer programming problem with budget constraints, and congestion considerations. An efficient variable neighborhood search procedure is proposed and computational experiments are performed on a large set of instances.Peer reviewedFinal Accepted Versio

The Incremental Cooperative Design of Preventive Healthcare Networks

This document is the Accepted Manuscript version of the following article: Soheil Davari, 'The incremental cooperative design of preventive healthcare networks', Annals of Operations Research, first published online 27 June 2017. Under embargo. Embargo end date: 27 June 2018. The final publication is available at Springer via http://dx.doi.org/10.1007/s10479-017-2569-1.In the Preventive Healthcare Network Design Problem (PHNDP), one seeks to locate facilities in a way that the uptake of services is maximised given certain constraints such as congestion considerations. We introduce the incremental and cooperative version of the problem, IC-PHNDP for short, in which facilities are added incrementally to the network (one at a time), contributing to the service levels. We first develop a general non-linear model of this problem and then present a method to make it linear. As the problem is of a combinatorial nature, an efficient Variable Neighbourhood Search (VNS) algorithm is proposed to solve it. In order to gain insight into the problem, the computational studies were performed with randomly generated instances of different settings. Results clearly show that VNS performs well in solving IC-PHNDP with errors not more than 1.54%.Peer reviewe

Using Big Data for the Mobile Facility Routing Problem in Healthcare Delivery

This work presents a mobile facility routing problem with a continuous-time planning horizon using real-time data from a server. A set of vehicles are scheduled and routed in order to provide healthcare services to people considering capacity restrictions and budget constraints. We modelled this problem as an infinite dimensional bi objective mixed-integer programming model and proposed heuristics to solve it. The performance of the heuristics in terms of their solution quality and run-time have been compared. A case study in Glasgow, Scotland is provided as well

Using Big Data for the Mobile Facility Routing Problem in Healthcare Delivery

This work presents a mobile facility routing problem with a continuous-time planning horizon using real-time data from a server. A set of vehicles are scheduled and routed in order to provide healthcare services to people considering capacity restrictions and budget constraints. We modelled this problem as an infinite dimensional bi objective mixed-integer programming model and proposed heuristics to solve it. The performance of the heuristics in terms of their solution quality and run-time have been compared. A case study in Glasgow, Scotland is provided as well

The single-allocation hierarchical hub median location problem with fuzzy demands

Although, many papers have appeared in the literature of hub location problem, most of them deal with the problem in a crisp environment. In this paper, the single-allocation hierarchical hub median problem (SA-H-MP) with fuzzy demands is addressed. The structure of the model is derived from Yaman (2009) and consists of a three-level network of demand nodes, non-central hubs, and central hubs. It has been assumed that the demands are not known precisely and are estimated using fuzzy variables. In order to solve the problem, a simulation-embedded variable neighborhood search (VNS) is applied. The results of running the proposed approach on the well-known CAB dataset verify that it is able to solve test problems with less than one percent of error

Fuzzy bi-objective preventive health care network design Fuzzy Bi-objective Preventive Health Care Network Design

International audiencePreventive health care is unlike health care for acute ailments, as people are less alert to their unknown medical problems. In order to motivate public and to attain desired participation levels for preventive programs, the attractiveness of the health care facility is a major concern. Health economics literature indicates that attractiveness to a facility is signi…cantly in ‡uenced by proximity of the clients to it. Hence attractiveness is generally modelled as a function of distance. However, abundant empirical evidence suggests that other qualitative factors such as perceived quality, attractions nearby, amenities, etc. also in ‡uence attractiveness. Therefore, a realistic measure should incorporate the vagueness in the concept of attractiveness to the model. The public policy makers should also maintain the equity among various neighborhoods, which should be considered as a second objective. Finally, even though general tendency in the literature is to focus on health bene…ts, the cost e¤ectiveness is still a factor that should be considered. In this paper, a fuzzy bi-objective model with budget constraints of the problem is developed. Later, by modelling the attractiveness by means of fuzzy triangular numbers and treating the budget constraint as a soft constraint, a modi…ed (and more realistic) version of the model is introduced. Two solution methodologies, namely fuzzy goal programming and fuzzy chance constrained optimization are proposed as solutions. Both the original and the modi…ed models are solved within the framework of a case study in Istanbul, Turkey. In the case study, the Microsoft Bing Map is utilized in order to determine more accurate distance measures among the nodes