Your browser doesn't support javascript.
Show: 20 | 50 | 100
Results 1 - 20 de 46
Filter
1.
Sustain Cities Soc ; 97: 104702, 2023 Oct.
Article in English | MEDLINE | ID: covidwho-20243597

ABSTRACT

The excessive traffic congestion in vehicles lowers the service quality of urban bus system, reduces the social distance of bus passengers, and thus, increases the spread speed of epidemics, such as coronavirus disease. In the post-pandemic era, it is one of the main concerns for the transportation agency to provide a sustainable urban bus service to balance the travel convenience in accessibility and the travel safety in social distance for bus passengers, which essentially reduces the in-vehicle passenger congestion or smooths the boarding-alighting unbalance of passengers. Incorporating the route choice behavior of passengers, this paper proposes a sustainable service network design strategy by selecting one subset of the stops to maximize the total passenger-distance (person × kilometers) with exogenously given loading factor and stop-spacing level, which can be captured by constrained non-linear programming model. The loading factor directly determines the in-vehicle social distance, and the stop-spacing level can efficiently reduce the ridership with short journey distance. Therefore, the sustainable service network design can be used to help the government minimize the spread of the virus while guaranteeing the service quality of transport patterns in the post-pandemic era. A real-world case study is adopted to illustrate the validity of the proposed scheme and model.

2.
Transportation Research Record ; 2677:313-323, 2023.
Article in English | Scopus | ID: covidwho-2316618

ABSTRACT

During the COVID-19 pandemic, authorities in many places have implemented various countermeasures, including setting up a cordon sanitaire to restrict population movement. This paper proposes a bi-level programming model to deploy a limited number of parallel checkpoints at each entry link around the cordon sanitaire to achieve a minimum total waiting time for all travelers. At the lower level, it is a transportation network equilibrium with queuing for a fixed travel demand and given road network. The feedback process between trip distribution and trip assignment results in the predicted waiting time and traffic flow for each entry link. For the lower-level model, the method of successive averages is used to achieve a network equilibrium with queuing for any given allocation decision from the upper level, and the reduced gradient algorithm is used for traffic assignment with queuing. At the upper level, it is a queuing network optimization model. The objective is the minimization of the system's total waiting time, which can be derived from the predicted traffic flow and queuing delay time at each entry link from the lower-level model. Since it is a nonlinear integer programming problem that is hard to solve, a genetic algorithm with elite strategy is designed. An experimental study using the Nguyen-Dupuis road network shows that the proposed methods effectively find a good heuristic optimal solution. Together with the findings from two additional sensitivity tests, the proposed methods are beneficial for policymakers to determine the optimal deployment of cordon sanitaire given limited resources. © National Academy of Sciences: Transportation Research Board 2021.

3.
International Journal of Production Economics ; : 108899, 2023.
Article in English | ScienceDirect | ID: covidwho-2313343

ABSTRACT

E-commerce is always a more diffused sales channel around the whole world market. The grocery market has been interested in the expansion of this phenomenon, especially during the COVID-19 pandemic emergency, when electronic grocery (e-grocery) shopping increased considerably. Moreover, it has remained a diffused selling channel also later, in the non-emergency state. To satisfy this specific market demand, grocery chains are facing the need for a redesign with a new logistic perspective. A grocer can carry out online orders in several ways;it can process them directly in stores using internal staff to shop from the shelves during off-peak hours. Alternatively, some local stores can be closed to customers and dedicated to online orders (dark stores). Another strategy is to carry out online orders from a single distribution centre (e-hub), using stores to complete orders with very fresh products and from which to carry out deliveries. Finally, online orders can be wholly managed by multi e-hubs. Each solution has different logistics costs and performances, influenced by online demand. For this reason, this work aims to present a cost-based function for grocery chains that compares four strategies to respond to e-grocery shopping. The cost function considers picking, refilling, and transport costs by varying orders and articles quantity. Further, we aim to minimise costs according to online order characteristics and volumes. We identify five decision variables to select the most suitable strategy for the design of the e-grocery network. Finally, a decision support system (DSS) is developed to define the best strategy based on the decision variables.

4.
Ann Oper Res ; : 1-73, 2023 May 09.
Article in English | MEDLINE | ID: covidwho-2315426

ABSTRACT

With the severe outbreak of the novel coronavirus (COVID-19), researchers are motivated to develop efficient methods to face related issues. The present study aims to design a resilient health system to offer medical services to COVID-19 patients and prevent further disease outbreaks by social distancing, resiliency, cost, and commuting distance as decisive factors. It incorporated three novel resiliency measures (i.e., health facility criticality, patient dissatisfaction level, and dispersion of suspicious people) to promote the designed health network against potential infectious disease threats. Also, it introduced a novel hybrid uncertainty programming to resolve a mixed degree of the inherent uncertainty in the multi-objective problem, and it adopted an interactive fuzzy approach to address it. The actual data obtained from a case study in Tehran province in Iran proved the strong performance of the presented model. The findings show that the optimum use of medical centers' potential and the corresponding decisions result in a more resilient health system and cost reduction. A further outbreak of the COVID-19 pandemic is also prevented by shortening the commuting distance for patients and avoiding the increasing congestion in the medical centers. Also, the managerial insights show that establishing and evenly distributing camps and quarantine stations within the community and designing an efficient network for patients with different symptoms result in the optimum use of the potential capacity of medical centers and a decrease in the rate of bed shortage in the hospitals. Another insight drawn is that an efficient allocation of the suspect and definite cases to the nearest screening and care centers makes it possible to prevent the disease carriers from commuting within the community and increase the coronavirus transmission rate.

5.
International Journal of Industrial Engineering-Theory Applications and Practice ; 30(1):246-255, 2023.
Article in English | Web of Science | ID: covidwho-2309729

ABSTRACT

The COVID-19 pandemic has significantly impacted e-commerce and the delivery service sector. As lockdowns and social distancing measures were put in place to slow the spread of the virus, many brick-and-mortar stores were forced to close, leading to an increase in online shopping. This situation led to a surge in demand for delivery services as more people turned to the internet to purchase goods. However, this increase in demand also created several challenges for delivery companies. They experienced delays in delivering packages due to increased volume, limited staff, and disruptions to supply chains. It led to more competition and increased pressure on delivery companies to improve their services and delivery times. To overcome such competition, collaboration among small and medium-sized delivery companies can be a good way to compete with larger delivery companies. By working together, small and medium-sized companies can combine their resources and expertise to offer more extensive coverage and competitive prices than they could individually. This can help them to gain market share and expand their customer base. This study proposes a network design model for collaboration with service class in delivery services considering multi-time horizon. The problem to be considered is deciding which company is dedicated to delivering certain types of items, such as regular or refrigerated items, in designated regions in each time horizon. During the agreed-upon timeframe, the companies operate, using each other's infrastructure (such as vehicles and facilities) and sharing delivery centers for the coalition's benefit to improve efficiency and reduce costs. We also propose a multi -objective, nonlinear programming model that maximizes the incremental profit of participating companies and a linearization methodology to solve it. The max-sum criterion and Shapley value allocation methods are applied to find the best solution and ensure a fair distribution of profits among the collaborating group. The efficiency of the suggested model is shown through a numerical illustration.

6.
Omega ; 114: 102750, 2023 Jan.
Article in English | MEDLINE | ID: covidwho-2307317

ABSTRACT

The COVID-19 pandemic - as a massive disruption - has significantly increased the need for medical services putting an unprecedented strain on health systems. This study presents a robust location-allocation model under uncertainty to increase the resiliency of health systems by applying alternative resources, such as backup and field hospitals and student nurses. A multi-objective optimization model is developed to minimize the system's costs and maximize the satisfaction rate among medical staff and COVID-19 patients. A robust approach is provided to face the data uncertainty, and a new mathematical model is extended to linearize a nonlinear constraint. The ICU beds, ward beds, ventilators, and nurses are considered the four main capacity limitations of hospitals for admitting different types of COVID-19 patients. The sensitivity analysis is performed on a real-world case study to investigate the applicability of the proposed model. The results demonstrate the contribution of student nurses and backup and field hospitals in treating COVID-19 patients and provide more flexible decisions with lower risks in the system by managing the fluctuations in both the number of patients and available nurses. The results showed that a reduction in the number of available nurses incurs higher costs for the system and lower satisfaction among patients and nurses. Moreover, the backup and field hospitals and the medical staff elevated the system's resiliency. By allocating backup hospitals to COVID-19 patients, only 37% of severe patients were lost, and this rate fell to less than 5% after establishing field hospitals. Moreover, medical students and field hospitals curbed the costs and increased the satisfaction rate of nurses by 75%. Finally, the system was protected from failure by increasing the conservatism level. With a 2% growth in the price of robustness, the system saved 13%.

7.
Applied Soft Computing ; 140, 2023.
Article in English | Scopus | ID: covidwho-2300249

ABSTRACT

In the 21st century, global supply chains have experienced severe risks due to disruptions caused by crises and serious diseases, such as the great tsunami, SARS, and, more recently, COVID-19. Building a resilient supply chain is necessary for business survival and growth. Similarly, there is increasing regulatory and social pressure for managers to continuously design and implement sustainable supply chain networks, encompassing economic, social, and environmental components. Hence, a panacea approach is required to establish a compromise position between resiliency concerns and sustainability responsibilities. To address this, this work presents a hybrid integrated BWM-CoCoSo-multi-objective programming model (BC-MOPM) formulated to deliver a compromise between resilience and sustainability supply chain network design (RS-SCND). First, a thorough literature review analysis is conducted to explore the relationship and correlation between resilience and sustainability to develop a framework for the resiliency and sustainability criteria, in a supply chain context. Second, four objectives were formulated, including the minimisation of total cost and environmental impact and the maximisation of social and resilience paradigms. A real two-tier supply chain network is deployed to evaluate the applicability of the developed BC-MOPM. Furthermore, sensitivity analysis is conducted to establish the relative importance of the identified criteria to prove the model's robustness. Results demonstrate the capability of the BC-MOPM in revealing trade-offs between the resiliency and sustainability aspects. © 2023 Elsevier B.V.

8.
Journal of Humanitarian Logistics and Supply Chain Management ; 13(2):140-156, 2023.
Article in English | ProQuest Central | ID: covidwho-2295632

ABSTRACT

PurposeThe COVID-19 pandemic has forced countries to consider how to reach vulnerable communities with extended outreach services to improve vaccination uptake. The authors created an optimization model to align with decision-makers' objective to maximize immunization coverage within constrained budgets and deploy resources considering empirical data and endogenous demand.Design/methodology/approachA mixed integer program (MIP) determines the location of outreach sites and the resource deployment across health centers and outreach sites. The authors validated the model and evaluated the approach in consultation with UNICEF using a case study from The Gambia.FindingsResults in The Gambia showed that by opening new outreach sites and optimizing resource allocation and scheduling, the Ministry of Health could increase immunization coverage from 91.0 to 97.1% under the same budget. Case study solutions informed managerial insights to drive gains in vaccine coverage even without the application of sophisticated tools.Originality/valueThe research extended resource constrained LMIC vaccine distribution modeling literature in two ways: first, endogenous calculation of demand as a function of distance to health facility location enabled the effective design of the vaccine network around convenience to the community and second, the model's resource bundle concept more accurately and flexibly represented complex requirements and costs for specific resources, which facilitated buy-in from stakeholders responsible for managing health budgets. The paper also demonstrated how to leverage empirical research and spatial analysis of publicly available demographic and geographic data to effectively represent important contextual factors.

9.
Engineering Applications of Artificial Intelligence ; 122, 2023.
Article in English | Scopus | ID: covidwho-2273844

ABSTRACT

The rapid growth of technology, environmental concerns, and disruptions caused by the COVID-19 pandemic have led researchers to pay more attention to an emerging concept called the fifth industrial revolution (I5.0). Despite the high importance of the I5.0, the literature shows that no study investigated the supply chain network design problem based on the I5.0 pillars. Hence, this research develops a multi-stage decision-making framework to configure a closed-loop supply chain based on I5.0 dimensions to cover this gap. In the first stage, the score of technologies that utilized in the supply chain is calculated using the analytic hierarchy process method. Afterwards, in the second stage, a mathematical model is proposed to configure the supply chain. Then, Furthermore, an efficient solution method, named the fuzzy lexicographic multi-choice Chebyshev goal programming method, is developed to obtain the optimal solution. In general, the main contributions of the current study can be divided into two major parts as follows: (i) the current study is the first research that incorporates the dimensions of the I5.0 into the supply chain network design problem, and (ii) this work develops a novel and efficient solution method. In this regard, the major problems and challenges that existed include the limitation of available resources in relation to Industry 5, especially in the field of the supply chain, as well as quantifying the elements of Industry 5.0 in the form of a mathematical programming model. © 2023

10.
Journal of Industrial and Management Optimization ; 19(4):3044-3059, 2023.
Article in English | Scopus | ID: covidwho-2269120

ABSTRACT

A painful lesson got from pandemic COVID-19 is that preventive healthcare service is of utmost importance to governments since it can make massive savings on healthcare expenditure and promote the welfare of the society. Recognizing the importance of preventive healthcare, this research aims to present a methodology for designing a network of preventive healthcare facilities in order to prevent diseases early. The problem is formulated as a bilevel non-linear integer programming model. The upper level is a facility location and capacity planning problem under a limited budget, while the lower level is a user choice problem that determines the allocation of clients to facilities. A genetic algorithm (GA) is developed to solve the upper level problem and a method of successive averages (MSA) is adopted to solve the lower level problem. The model and algorithm is applied to analyze an illustrative case in the Sioux Falls transport network and a number of interesting results and managerial insights are provided. It shows that solutions to medium-scale instances can be obtained in a reasonable time and the marginal benefit of investment is decreasing. © 2023, Journal of Industrial and Management Optimization. All Rights Reserved.

11.
Journal of Transportation Engineering Part A: Systems ; 149(4), 2023.
Article in English | Scopus | ID: covidwho-2259160

ABSTRACT

A transit network design frequency setting model is proposed to cope with the postpandemic passenger demand. The multiobjective transit network design and frequency setting problem (TNDFSP) seeks to find optimal routes and their associated frequencies to operate public transport services in an urban area. The objective is to redesign the public transport network to minimize passenger costs without incurring massive changes to its former composition. The proposed TNDFSP model includes a route generation algorithm (RGA) that generates newlines in addition to the existing lines to serve the most demanding trips, and passenger assignment (PA) and frequency setting (FS) mixed-integer programming models that distribute the demand through the modified bus network and set the optimal number of buses for each line. Computational experiments were conducted on a test network and the network comprising the Royal Borough of Kensington and Chelsea in London. © 2023 American Society of Civil Engineers.

12.
International Journal of Computers and their Applications ; 29(4):215-228, 2022.
Article in English | Scopus | ID: covidwho-2252388

ABSTRACT

Despite the effectiveness of social isolation and, in particular, contact tracing for infection management, there are a number of drawbacks, including that it is time-consuming, labor-intensive, and adhoc. Following the COVID-19 outbreak, a number of mobile technologies are emerging to combat the inefficiencies of human contact tracing. However, there is a lack of actual, transparent platform design, and the production of maps for active infection, particularly in the state-of-the-art Blockchain technology. In this paper we introduce CTChain, a blockchainbased tool that collects, organizes, and generates maps of active infections to assist public health officials in their work. Utilizing a hierarchical network architecture, a regional map for active infection is built by navigating via a cache memorystored blockchain. Our architecture continuously filters out outdated infections to produce batches of the most pertinent dynamic regional data, which may be utilized to issue timely health recommendations and temporarily seal off high-infection areas. CTChain's platform can map the active infections across three different parameters: sparse vs densely populated region, number of people in each location, and initial infection rate. We can examine infection transmission and region "popularity” on a per-region basis because of our region handler capabilities. Due to the network's widespread storage of many copies of the chain, our model is safeguarded against single points of failure. © 2022, International Society for Computers and Their Applications. All rights reserved.

13.
Operational Research ; 23(1):14, 2023.
Article in English | ProQuest Central | ID: covidwho-2250347

ABSTRACT

The outbreak of the COVID-19 pandemic in recent years has raised serious concerns about the distribution of fast-moving consumer goods products, given the freshness of their use. On the one hand, the distribution of fast-moving consumer goods with multiple vehicles has led to maintaining the freshness of items at the supply chain level, and on the other hand, it involves the high costs of using vehicles. Congestion of vehicles and drivers in the distribution of items has also increased the possibility of COVID-19 transmission. The importance of the above issue has led to the modeling of a multi-level supply chain problem in the FMCG industry by considering the freshness of items to reduce COVID-19 transmission. The most important issue considered in this article is to send fresh food in the shortest possible time to customers who cannot go to stores and wait in line to buy items in the conditions of Covid-19. Therefore, the designed model provides the possibility for customers to receive fresh food in addition to reducing costs and also reduce the possibility of contracting Covid-19. Designed supply chain network levels include suppliers of raw materials, manufacturers of consumer goods, distributors and end customers. In order to optimize the objectives of the problem, including minimizing the total costs of supply chain network design and maximizing the freshness of items, various strategic and tactical decisions such as locating potential facilities, routing vehicles, and optimally allocating the flow of goods should be made. Since the supply chain network model is considered to be NP-hard, meta-heuristic algorithms have been used to solve the problem by providing a modified priority-based encoding. The results show the high efficiency of the proposed solution method in a short time.

14.
4th International Conference on Soft Computing and its Engineering Applications, icSoftComp 2022 ; 1788 CCIS:123-134, 2023.
Article in English | Scopus | ID: covidwho-2281697

ABSTRACT

With the evolving digitization, services of Cloud and Fog make things easier which is offered in form of storage, computing, networking etc. The importance of digitalization has been realized severely with the home isolation due to COVID-19 pandemic. Researchers have suggested on planning and designing the network of Fog devices to offer services nearby the edge devices. In this work, Fog device network design is proposed for a university campus by formulating a mathematical model. This formulation is used to find the optimal location for the Fog device placement and interconnection between Fog devices and the Cloud (Centralized Information Storage). The proposed model minimizes the deployment cost and the network traffic towards Cloud. The IBM CPLEX optimization tool is used to evaluate the proposed multi-objective optimization problem. Classical multi-objective optimization method, i.e., Weighted Sum approach is used for the purpose. The experimental results exhibit optimal placement of Fog devices with minimum deployment cost. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.

15.
International Journal of Production Research ; 61(8):2795-2827, 2023.
Article in English | ProQuest Central | ID: covidwho-2281578

ABSTRACT

In this study, we focus on ripple effect mitigation capability of the Indian pharmaceutical distribution network during disruptions like COVID-19 pandemic. To study the mitigation capabilities, we conduct a multi-layer analysis (network, process, and control levels) using Bayesian network, mathematical optimisation, and discrete event simulation methodologies. This analysis revealed an associative relationship between ripple effect mitigation capabilities and network design characteristics of upstream supply chain entities. Using stochastic optimisation and Lagrangian relaxation, we then find ideal candidates for regional distribution centres at the downstream level. We then integrate these downstream locations with other supply chain entities for building the network optimisation and simulation model to analyse overall performance of the system. We demonstrate utility of our proposed methodology using a case study involving distribution of N95 masks to ‘Jan Aushadhi' (peoples' medicines) stores in India during COVID-19 pandemic. We find that supply chain reconfiguration improves service level to 95.7% and reduces order backlogs by 10.7%. We also find that regional distribution centres and backup supply sources provide overall flexibility and improve occupational health and safety. We further investigate alternate mitigation capabilities through fortification of suppliers' workforce by vaccination. We offer recommendations for policymakers and managers and implications for academic research.

16.
25th International Conference on Interactive Collaborative Learning, ICL 2022 ; 633 LNNS:718-729, 2023.
Article in English | Scopus | ID: covidwho-2279878

ABSTRACT

The new reality of the coronavirus lockdown has prohibited the students' physical presence in laboratories. Administrators, teachers, and students had to think of new alternatives to hold meetings by adopting a virtual format through the development of rapidly available and broadly accessible online resources. Online Open Educational Resources (OERs) can be used in the form of cloud applications to virtualize computers or other physical sciences laboratories, which are necessary for the realization of the objectives of the courses. OERs can efficiently and effectively prepare students to be able to practice their skills. In parallel, OERs offer a degree of flexibility to the teachers, as they allow them to manage information in multiple ways and at the same time accommodate the presentation of knowledge from multiple perspectives. In this article, we propose the use of computer network simulation software as a teaching method in the form of OERs. In this context, we support the teaching of the administrative perspective of a computer network management course utilizing OERs. We explore the effectiveness of the network simulation software Packet Tracer anywhere in online learning of both synchronous and asynchronous education environments. In particular, we examine its suitability and usability in light of group activities at the level of higher education. We investigate its functionality and the teaching benefits that arise through collaborative learning scenarios in a computer lab suitable for the course of network management. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.

17.
Journal of Environmental Engineering (United States) ; 149(1), 2023.
Article in English | Scopus | ID: covidwho-2245005

ABSTRACT

Pressure sewer networks offer a flexible alternative to more traditional gravity-based systems for the conveyance of wastewater. Some of the issues associated with pressure sewer networks (e.g., odor, septicity) arise from inappropriate design assumptions. Daily inflow volumes are a crucial part of the design of pressure sewer systems;gravity design parameters are presently used to design pressure sewer networks in New Zealand. This study analyzed flow data from six representative pressure sewer networks (approximately 24% of operating pump units in New Zealand) to identify the daily inflow volumes per connected pump unit. The results indicated that the median inflow volume was approximately 410 L/pump unit/day. This inflow is much lower than current council design standard assumptions, which range from 650 to 1,000 L/pump unit/day. Pressure sewer network designs using higher daily loading rates may result in oversized networks that are detrimental to the network's operation and performance, especially for meeting minimum self-cleansing velocities and wastewater retention times. The data collection period included the first COVID-19 lockdown in New Zealand. Four lockdown levels were introduced, with Level 4 and Level 3 being the most restrictive and requiring all but essential workers to stay and work from home. Levels 1 and 2 allowed people to return to their place of work. The data indicated that the Level 4 lockdown period caused a 25% increase in daily inflow volumes. In comparison, the Level 3 and 2 lockdown periods increased the daily inflow volumes by 20% and 15%, respectively. The analysis also included the networks' wet-weather responses. Minor rain events did not significantly affect the daily inflow volumes. However, gravity networks that have been retrofitted with pressure sewer networks may be more subject to aging or damaged laterals and illegal stormwater connections, both of which are likely to result in a more significant wet-weather response. The paper also discusses the issues associated with an overreliance on standardized design methods without understanding their proper application and the pitfalls of adopting gravity sewer design assumptions for pressure sewer network designs. The findings of this paper will further allow determination of the sensitivity of network design outcomes, performance, and maintenance requirements to the design methods and assumptions for pressure sewer networks, not only in New Zealand but in any country that uses the technology. © 2022 American Society of Civil Engineers.

18.
Omega (United Kingdom) ; 116, 2023.
Article in English | Scopus | ID: covidwho-2238553

ABSTRACT

The recent COVID-19 pandemic showed that supply chain resilience is essential for continuity of many businesses, especially retail chains. However, there are still some challenges that have received little attention in the resilient supply chain network design (RSCND) literature. While numerous resilience strategies have been proposed to make supply chain networks resilient against disruptions, very few papers have discussed why and how those resilience strategies are selected out of many potential candidates given various sources of disruption, i.e., natural, man-made, and pandemic-oriented disruptions. The aim of this paper is to propose a multi-methodological approach, based on resource dependence theory and two-stage stochastic programming, for choosing the right resilience strategies in a RSCND problem considering their positive and negative synergistic effects under resource constraints. These interactions among resilience strategies can be referred to as supply chain dynamics. We then present a novel approach for determining the most suitable combination of candidate strategies with respect to these synergistic effects. The criticality of nodes and the susceptibility of the network in different echelons are also examined via simulating the disruptive risks in hidden and unexpected places. We provide a case study from the retail industry that illustrates the potentially significant impacts of network disruptions. Via extensive stress-testing, we show the benefits of applying multiple resilience capabilities simultaneously. Our findings demonstrate the importance of considering synergistic effects among resilience strategies under budget limitations for supply chain resilience. © 2022 Elsevier Ltd

19.
Socioecon Plann Sci ; : 101439, 2022 Sep 22.
Article in English | MEDLINE | ID: covidwho-2236307

ABSTRACT

In uncertain circumstances like the COVID-19 pandemic, designing an efficient Blood Supply Chain Network (BSCN) is crucial. This study tries to optimally configure a multi-echelon BSCN under uncertainty of demand, capacity, and blood disposal rates. The supply chain comprises blood donors, collection facilities, blood banks, regional hospitals, and consumption points. A novel bi-objective mixed-integer linear programming (MILP) model is suggested to formulate the problem which aims to minimize network costs and maximize job opportunities while considering the adverse effects of the pandemic. Interactive possibilistic programming is then utilized to optimally treat the problem with respect to the special conditions of the pandemic. In contrast to previous studies, we incorporated socio-economic factors and COVID-19 impact into the BSCN design. To validate the developed methodology, a real case study of a Blood Supply Chain (BSC) is analyzed, along with sensitivity analyses of the main parameters. According to the obtained results, the suggested approach can simultaneously handle the bi-objectiveness and uncertainty of the model while finding the optimal number of facilities to satisfy the uncertain demand, blood flow between supply chain echelons, network cost, and the number of jobs created.

20.
Omega ; : 102841, 2023.
Article in English | ScienceDirect | ID: covidwho-2181964

ABSTRACT

Supply chain (SC) resilience is imperative to cope with disruptions using some preparedness and recovery capabilities such as network redundancy (e.g., backup suppliers) and process flexibility (e.g., capacity agility). These capabilities frame an SC resilience portfolio. Both designing a resilient portfolio and recovering in case of a real disruption require investments. This paper presents a new mathematical model for designing an efficient resilience portfolio in a multi-echelon SC. Through computational and comparative analyses using a real-life case-study, we demonstrate that our model allows increasing resilience at minimal costs by determining an optimal combination of preparedness and recovery investments. Interestingly, the optimal solutions (i.e., efficient resilient SC designs) increase SC efficiency even in business-as-usual scenarios. This result contributes to the literature on transforming resilience from an expensive spend to a value-creation asset. We illustrate our approach using a real-life industrial example that allows for the identification of important relations between disruption duration/magnitude and the efficiency of preparedness and recovery strategies. Based on computational, comparative, and case-study analyses, we deduce and generalize managerial implications at the network, supplier, and manufacturer levels. We take an extra step by extrapolating our major findings and generalized managerial implications toward the COVID-19 pandemic setting. The outcome of our research can be instructive for SC managers when deciding on investments in resilient redundancy allocation as a part of preparedness strategy and efficient recovery deployment.

SELECTION OF CITATIONS
SEARCH DETAIL