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Ambulance location routing problem considering all sources of uncertainty: Progressive estimating algorithm
No full textInternational audienceThe main concern of any emergency medical services (EMS) in the world is to provide quality services to emergency calls in the shortest possible time. In this paper, the Ambulance Location Routing problem (ALRP) is proposed that is a mathematical attempt to obtain optimal cost-oriented strategic decisions (locating EMS centers and allocating ambulance fleet) in a way that guarantees service quality factors like response time, service level, and definite treatment time through optimal ambulance routing. In response to the concerns that emergency medical services deal with, in this research, a novel mixed-integer two-stage stochastic programming model is developed that can consider the uncertain nature of parameters like emergency calls, travel times, and pathways, simultaneously. Considering a heterogeneous fleet of ambulances to provide specialized out-of-hospital services and to use the treatment golden time, and considering different types of patients in terms of the need to be transferred to the hospital, are among the most vital innovations of the proposed ALRP. To tackle the computational complexity, a new decomposition-based heuristic method called the Progressive Estimating Algorithm (PEA) is developed. PEA is a modified version of the classic PHA and solves its drawbacks, like the possibility of being placed in a loop or prolonging the solution time by changing the method of calculating the first stage variables in each iteration. Therefore, by considering a large number of scenarios, PEA can reach feasible near-optimal solutions more efficiently. We have employed the actual data of a city with nearly 800.000 population, as a case study to validate the proposed ALRP model and the PEA method. The obtained results demonstrate that the proposed ALRP solution is valid, and the PEA can reach the near-optimal solution, in a very reasonable time, and with no exception, outperform the PHA. The results also show that the ALRP model reduces costs on average by 30% compared to a benchmark model. In addition, it is found that the solution obtained for the case study can reduce costs by 58% compared to the current state of the EMS in this city while guaranteeing the quality of services. Furthermore, the need to use a heterogeneous fleet of ambulances and scattered stations in the region is recommended to improve the performance of EM services. Finally, the unique way of looking at the integrated problem of location, allocation, and routing in the proposed ALRP and the idea of PEA are attractive for further studies in the field of EMS planning and other optimization problems, and several suggestions for future studies are mentioned in Conclusion Section
Business Goal Difficulty and Socially Irresponsible Executive Behavior: The Mediating Role of Focalism
No full textInternational audienceExecutive social irresponsibility has received increasing research attention in recent years, following the consensus for a broader stakeholder approach to managerial decision making. Despite the importance of the subject, there remains insufficient research on contextual factors that mold executives’ orientation toward social responsibility. Through three studies, we demonstrate that difficult business goals can reduce executives’ tendency to consider social responsibility in their decision making. Further, we find that focalism—a cognitive bias based on affective forecasting theory—can mediate positive relationships between business goal difficulty and socially irresponsible executive behavior. Our findings also suggest that, expanding executives’ thought processes beyond the narrow focus of a business goal achievement can be a good strategy in reducing socially irresponsible executive behavior, even in the presence of difficult goals
Optimizing price, order quantity, and return policy in the presence of consumer opportunistic behavior for online retailers
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Effectiveness of B2B social media marketing: The effect of message source and message content on social media engagement
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How Foreign Social Media Influencers Help Shape Destination Country's Tourism Image: The Case of South Korea's Tourism Image in France
No full textInternational audienceIn the context of tourism, the current study differentiates social media influencers (SMIs) as local SMIs and foreign SMIs. The current study argues that foreign SMIs help to create a positive (or sometimes negative) image of another destination country abroad that they have visited or lived in, unlike local SMIs who mostly help promote touristic places of their own country in their own country. While prior studies have investigated the influence of social media influencers (SMIs) in travel decisions in general, it is not clear whether foreign SMIs can help shape another destination country's tourism image (DCTI) abroad. The current study fills this gap by investigating French SMIs' influence in shaping South Korea's destination country image in France. The leading French SMIs who actively create and share content about South Korea on their social media channels, such as YouTube, Instagram, Tik Tok, and Twitch, are identified and analyzed. Applying the netnographic method to four SMIs' communities of followers shows that French SMIs directly influence the DCTI of South Korea in France by influencing their cognitive, affective, and conative dimensions, although the effect on each varied. Moreover, the affective route had the highest impact, followed by the cognitive and conative route
To Pool or Not to Pool in Carbon Quotas: Analyses of Emission Regulation and Operations in Supply Chain Supernetwork under Cap-and-Trade Policy
No full textInternational audienceCarbon emission control and maintaining economic growth drive firms and governments to strike a balance between these two aspects via environmental policies. Inspired by diverse carbon permit trading practices, we study the impact of two variant cap-and-trade schemes on supply chain performance and emission reduction. Focusing on a realistic supply chain supernetwork, we examine the operational decisions and emission mitigations of the system under the carbon caps-pooling and caps-nonpooling schemes which reflect two typical modes of carbon quota in practice. We exploit game theoretical models to characterize the strategic interactions of supernetwork node firms, and then transform them into equivalent variational inequality problems to derive the associated equilibria in different scenarios. We find that the carbon caps-pooling scheme yields a win–win outcome in terms of the environmental and economic performance and the carbon permit sale price affects the decreasing rate of carbon intensity more effectively than the purchasing price. Moreover, the caps-pooling scheme further restrains firms’ opportunistic behaviors of lowering production and selling surplus carbon permits at a high price. Notably, comparing the two carbon schemes implies that under the cap-and-trade policy governments should stimulate firms adopt the caps-pooling scheme with emission permits trading, and accordingly firms have more flexible control over carbon permits. We further conduct computational analysis to validate and illustrate the results, which indicates the robust effect of caps-pooling scheme on the supply chain supernetwork under distinct market structures
The strategic impact of vertical integration on non-deceptive counterfeiting
No full textInternational audienceThe field of paradox studies keeps struggling to put the notion of paradox into the very centre of organizational life and managerial decision-making, with mixed success. We argue that this research ambition can be realized much more effectively by anchoring the field in three interrelated conceptual approaches which build on paradox as the paradigmatic point of departure. These approaches include Spencer Brown’s form calculus, Niklas Luhmann’s systems and organization theory, and the traditional Indian logical construct of tetralemma. In the proposed argument, paradox constitutes the very identity of organizations as (re-entries of) distinctions drawn in the environment; it is actualized in every act of organizational decision communication, as well as in the process of the continual vanishing and renewal of such acts. In this conception of organizational life, the key challenge is to debunk false distinctions by using tetralemmatization strategies that entail a radical questioning of the problematic observational perspectives
The Role of Sustainability and Innovation in Financial Services Business Transformation
No full textInternational audiencePurpose: This study discusses the effects of transformative service in the financial sector. Unlike conventional research, it reports how business transformation can play a vital role in human well-being. The main objective is to reveal how financial services can affect the welfare of people, communities, regions, and worldwide perspectives. Design/Methodology/Approach: The study used Confirmatory factor analysis and Structural Equation Modeling using SPSS (Amos). Findings: While appreciating the role of consumers as agents of service-driven business transformation, the study demonstrates how service transformation can promote an ecosystem that helps to accomplish rising sustainability goals. Originality: The main focus was to explain how social and environmental sustainability, responsible consumption and innovativeness are related to a firm’s attractiveness, value creation and customer satisfaction. Research Limitations: This study uses a cross-sectional survey design and it doesn’t have a holistic approach for all stakeholders. Predominantly, it considers the customer as a change agent in business transformation. Practical Implications: The study discusses a broader customer perspective instead of an extremely narrow and limiting traditional dyadic firm-customer perspective. It can enhance responsible production and consumption. It develops a comprehensive framework to help academicians, service leaders, and policymakers to recognize and solve service systems’ unsustainability. Social Implications: The research contributes to addressing, understanding, upgrading, and integrating the financial service system for business transformation, which can positively influence individuals and collectives.Source : editor
Building viable stockpiles of personnel protective equipment
No full textInternational audienceMany stockpiled personnel protective equipment (PPE) were of no use during COVID-19 because they have expired. The need for rethinking past approaches of building PPE stockpiles without planning for their timely rotation has become clear. We develop a game-theoretic pandemic preparedness model for single and multiple PPE products for a budget-constrained governmental organization (GO) supplied by a manufacturer. The GO maximizes preparedness, measured by the service rate of PPE, whereas the manufacturer maximizes profit. The manufacturer supplies the PPE stockpile in the first year. Thereafter, the manufacturer buys back a quantity of older PPE from the GO annually and sells the GO the same quantity of new PPE. The manufacturer sells older PPE in the market place. We find that this approach induces the manufacturer to rotate inventory in the stockpile. Joint determination of the stockpile size and its rotation results in no waste from expired PPE and is better than separately determining the stockpile size and then determining how to rotate it. Using insights from the single PPE model, we examine the optimal budget allocation among multiple PPE products. We also consider the effect of spot market prices of PPE during a pandemic on the optimal stockpile sizes. We find that spot market prices of PPE can have a significant effect on the optimal stockpile sizes. We examine the performance of the proposed approach in a manufacturers-distributor-GO supply chain and with an option for the GO to invest in the manufacturer’s volume flexibility and show its effectiveness
Coordinating vessel recovery actions: Analysis of disruption management in a liner shipping service
No full textInternational audienceDisruptions often occur in liner shipping networks, and they are costly. When they occur, freight companies evaluate their effects on freightage in the pipeline and take the appropriate recovery actions by balancing customer service levels and increases in fuel consumption while accounting for environmental impact (greenhouse gas (GHG) emissions). The paper, therefore, develops an integrated mixed-integer programming problem (MIPP) that jointly minimizes the total voyage and transshipment costs and penalty charges for emitting GHG excess amounts beyond what is allowed. It does so by recovering a pre-established schedule of disrupted containerships. The solution to the MIPP suggests how to reconfigure the liner shipping network when skipping one or more call ports and determines the optimal velocity on assigned routes. The paper also develops and proposes a new and efficient algorithm based on the Crowd-Learning Particle Swarm Optimization (CLPSO) to solve this large-scale problem and shows the CLPSO to be superior to the potential ones in the literature. Computational experiments, based on data from a maritime shipping company, demonstrate the effectiveness of both the MIPP and CLPSO using several comparative metrics with suitable assumptions. The numerical results show that the developed MIPP has a potential application in practice