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

Dynamic temporary blood facility location-allocation during and post-disaster periods

The key objective of this study is to develop a tool (hybridization or integration of different techniques) for locating the temporary blood banks during and post-disaster conditions that could serve the hospitals with minimum response time. We have used temporary blood centers, which must be located in such a way that it is able to serve the demand of hospitals in nearby region within a shorter duration. We are locating the temporary blood centres for which we are minimizing the maximum distance with hospitals. We have used Tabu search heuristic method to calculate the optimal number of temporary blood centres considering cost components. In addition, we employ Bayesian belief network to prioritize the factors for locating the temporary blood facilities. Workability of our model and methodology is illustrated using a case study including blood centres and hospitals surrounding Jamshedpur city. Our results shows that at-least 6 temporary blood facilities are required to satisfy the demand of blood during and post-disaster periods in Jamshedpur. The results also show that that past disaster conditions, response time and convenience for access are the most important factors for locating the temporary blood facilities during and post-disaster periods

Adaptive mechanisms of plants against salt stress and salt shock

Salinization process occurs when soil is contaminated with salt, which consequently influences plant growth and development leading to reduction in yield of many food crops. Responding to a higher salt concentration than the normal range can result in plant developing complex physiological traits and activation of stress-related genes and metabolic pathways. Many studies have been carried out by different research groups to understand adaptive mechanism in many plant species towards salinity stress. However, different methods of sodium chloride (NaCl) applications definitely give different responses and adaptive mechanisms towards the increase in salinity. Gradual increase in NaCl application causes the plant to have salt stress or osmotic stress, while single step and high concentration of NaCl may result in salt shock or osmotic shock. Osmotic shock can cause cell plasmolysis and leakage of osmolytes in plant. Also, the gene expression pattern is influenced by the type of methods used in increasing the salinity. Therefore, this chapter discusses the adaptive mechanism in plant responding to both types of salinity increment, which include the morphological changes of plant roots and aerial parts, involvement of signalling molecules in stress perception and regulatory networks and production of osmolyte and osmoprotective proteins

A LOCATION-INVENTORY MODEL INCLUDING DELIVERY DELAY COST AND CAPACITY CONSTRAINTS IN A STOCHASTIC DISTRIBUTION NETWORK

<p>ENGLISH ABSTRACT: In this paper, we present a distribution network design problem in a supply chain system that minimises the total cost of location, inventory, and delivery delay. Customers’ demands are random, and multiple capacity levels are available for the distribution centers. The problem is first formulated as a mixed integer convex programming model to optimally solve medium-sized instances, and then a heuristic is developed for solving large-sized instances.</p><p>AFRIKAANSE OPSOMMING: In hierdie artikel word ‘n distribusienetwerkprobleem in ‘n voorsieningsketting voorgehou waar die totale koste van die ligging, voorraad en afleweringsvertragings geminimiseer word. Die vraag is lukraak en verskeie kapasiteitsvlakke is beskikbaar in die verspreidingsentra. Die problem word eers geformuleer as ‘n gemengde-heeltal-konvekse model sodat mediumgrootte gevalle geoptimiseer kan word, waarna ‘n heuristieke benadering ontwikkel word vir die oplos van grootskaalse aktiwiteite.</p&gt

Two stage heuristic algorithm for logistics network optimization of integrated location-routing-inventory

To reduce the cost of logistics, optimize logistics warehousing layout and logistics distribution efficiency, logistics network of the integrated location-routing-inventory was studied. In this paper, we present a model of integrated Location-Routing and Inventory problem (ILRIP) that considers the selection of warehouses location, the inventory of products, and vehicle routing. Aiming at the characteristics of proposed model, a two-stage optimization problem is designed, and two main objective functions are established to minimize the expected total cost of inventory and location selection and distribution costs with time windows. Considering multiple constraints, the multi-objective optimization problems is designed. We solve the developed mathematical model by genetic algorithm (GA), then we code in MATLAB, a case study is proposed to prove industrial practicality of the model

Detection of human herpes virus type-6 in patients undergoing hemodialysis

Aim: To investigate the epidemiology of human herpes virus type-6 (HHV-6) among hemodialysis (HD) patients. Materials & methods: DNA was extracted from plasma samples of 149 patients undergoing HD with no history of organ transplantation from 2011 to 2013. Presence of HHV-6 was investigated by using real-time PCR. Results: Diabetes (36.2) and hypertension (28.8) were two major factors for HD. The HHV-6 DNA was identified in eight patients (5.37). Conclusion: This study is one of the few reports of HHV-6 infection among HD patients. In HD patient population, it is critical to improve standards of infection control in dialysis and expand treatment coverage. Furthermore, studies on clinical implications of HHV-6 infection in HD patients are crucial. © 2018 Future Medicine Ltd

Tractable Risk Measures for the Selective Scheduling Problem with Sequence-Dependent Setup Times

Quantifying and minimizing the risk is a basic problem faced in a wide range of applications. Once the risk is explicitly quantified by a risk measure, the crucial and ambitious goal is to obtain risk-averse solutions, given the computational hurdle typically associated with opti- mization problems under risk. This is especially true for many difficult combinatorial problems, and notably for scheduling problems. This paper aims to present a few tractable risk measures for the selective scheduling problem with parallel identical machines and sequence-dependent setup times. We indicate how deterministic reformulations can be obtained when the distributional information is limited to first and second-order moment information for a broad class of risk measures. We propose an efficient heuristic for addressing the computational difficulty of the resulting models and we showcase the practical applicability of the pro- posed approach providing computational evidence on a set of benchmark instances