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Mehmet Kursat Oksuz and Sule Itir Satoglu
Disaster management and humanitarian logistics (HT) play crucial roles in large-scale events such as earthquakes, floods, hurricanes and tsunamis. Well-organized disaster response…
Abstract
Purpose
Disaster management and humanitarian logistics (HT) play crucial roles in large-scale events such as earthquakes, floods, hurricanes and tsunamis. Well-organized disaster response is crucial for effectively managing medical centres, staff allocation and casualty distribution during emergencies. To address this issue, this study aims to introduce a multi-objective stochastic programming model to enhance disaster preparedness and response, focusing on the critical first 72 h after earthquakes. The purpose is to optimize the allocation of resources, temporary medical centres and medical staff to save lives effectively.
Design/methodology/approach
This study uses stochastic programming-based dynamic modelling and a discrete-time Markov Chain to address uncertainty. The model considers potential road and hospital damage and distance limits and introduces an a-reliability level for untreated casualties. It divides the initial 72 h into four periods to capture earthquake dynamics.
Findings
Using a real case study in Istanbul’s Kartal district, the model’s effectiveness is demonstrated for earthquake scenarios. Key insights include optimal medical centre locations, required capacities, necessary medical staff and casualty allocation strategies, all vital for efficient disaster response within the critical first 72 h.
Originality/value
This study innovates by integrating stochastic programming and dynamic modelling to tackle post-disaster medical response. The use of a Markov Chain for uncertain health conditions and focus on the immediate aftermath of earthquakes offer practical value. By optimizing resource allocation amid uncertainties, the study contributes significantly to disaster management and HT research.
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Limin Su, YongChao Cao, Huimin Li and Chengyi Zhang
The optimal payment in the whole operation and maintenance period of water environment treatment PPP projects has become the main approach to realize sustainable development of…
Abstract
Purpose
The optimal payment in the whole operation and maintenance period of water environment treatment PPP projects has become the main approach to realize sustainable development of projects. This study is aimed at constructing an effective payment model for the whole life period of projects to achieve win-win among all stakeholders, so as to provide a theoretical reference and managerial implications for the public sector in the whole operation and maintenance period.
Design/methodology/approach
In the whole operation and maintenance period of water environment treatment PPP projects, this article investigates how the public sector optimizes the payment in the whole operation and maintenance period of projects. Firstly, the projects' whole operation and maintenance period is divided into several stages according to the performance appraisal period. And then, the multi-stage dynamic programming model is constructed to design the payment construct model for the public sector in each performance appraisal stage. The payment from the public sector is the decision variable, and the deduction from the private sector is a random variable.
Findings
The optimal payment model showed that the relatively less objective weight of public sector leaded to its relatively more total payment and vice versa. Therefore, the sustainable development of the projects can only be ensured when the objective weights both of them should be balanced. Additionally, the deduction from the performance appraisal of private sector plays an important role in the model construction. The larger deduction the private sector undertakes, the smaller profits private sector has. Since the deduction at each stage is a random variable, the deduction varies with the different probability distributions obeyed by the practical deduction in each stage.
Research limitations/implications
The findings from this study have provided theoretical and application references, and some managerial implications are also given. First, the improvement of the pricing system of public sector should be accelerated. Second, the reasonable profit of the private sector must be guaranteed. While pursuing the maximization of social benefits, the public sector should make full use of the price sharing mechanism in the market and supervise the real income situation of the private sector. Third is increasing the public to participate in pricing. Additionally, it is a limitation that the deduction is assumed to conform to a uniform distribution in this study. Other probability distributions on deduction can be essentially further sought, so as to be more line with the actual situation of the projects.
Originality/value
The optimal payment in whole operation and maintenance period of the projects has become an important issue, which is a key to project success. This study constructs a multi-stage dynamic programming model to optimize payment in the whole period of projects. Additionally, this study adds its value through deeply developing the new theories of optimal payment to more suitable for the practical problems, so that to optimize the design of payment mechanism. Meanwhile, a valuable reference for public and private sectors is provided to ensure the sustainable development of the projects.
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Harry J. Paarsch and John Rust
The authors construct an intertemporal model of rent-maximizing behavior on the part of a timber harvester under potentially multidimensional risk as well as geographical…
Abstract
The authors construct an intertemporal model of rent-maximizing behavior on the part of a timber harvester under potentially multidimensional risk as well as geographical heterogeneity. Subsequently, the authors use recursive methods (specifically, the method of stochastic dynamic programing) to characterize the optimal policy function – the rent-maximizing timber-harvesting profile. One noteworthy feature of their application to forestry in the province of British Columbia, Canada is the unique and detailed information the authors have organized in the form of a dynamic geographic information system to account for site-specific cost heterogeneity in harvesting and transportation, as well as uneven-aged stand dynamics in timber growth and yield across space and time in the presence of stochastic lumber prices. Their framework is a powerful tool with which to conduct policy analysis at scale.
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Bingchang Ni and Constantinos Sourkounis
Wind energy plays a very important role in the future electrical power supply. With growing shares, the focus of the plant control will have to shift from maximum power yield to…
Abstract
Purpose
Wind energy plays a very important role in the future electrical power supply. With growing shares, the focus of the plant control will have to shift from maximum power yield to grid friendly aspects, like stable power output despite fluctuating wind power. The purpose of this paper is to design a new operation management for wind energy converters that combines high‐energy yield, grid friendly power output characteristics and the ability to adapt to changing wind conditions.
Design/methodology/approach
An operation control based on stochastic dynamic optimization was developed for the special demands of variable speed wind energy converters. The task of the operation control is to set the appliance to the optimal operation point, following the above‐mentioned goals by adapting the control pattern to changing wind conditions.
Findings
It is shown that the novel control concept, the iterative self‐adapting system management with stochastic dynamic optimization, is able to control wind energy converters in such a way that the effect of the stochastic fluctuating wind energy supply on the output power fluctuation is smoothed while maintaining a high‐energy yield.
Originality/value
This non‐linear stochastic dynamic optimization structure has two special characteristics, first is the iterative self‐adaptation, and second is the optimization for an infinite process, while the optimization criteria are high‐power yield and low‐power output fluctuations. This will be of great value for further increase of wind energy converters in the electrical power supply.
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Yuri Yatsenko and Natali Hritonenko
Despite the existence of multiple asset replacement theories, the economic life replacement method remains a major practical technique for making rational machine replacement…
Abstract
Purpose
Despite the existence of multiple asset replacement theories, the economic life replacement method remains a major practical technique for making rational machine replacement decisions. The purpose of this paper is to bridge this method with comprehensive data analytic tools and make it applicable it to modern business reality with abundant data on operating and replacement costs.
Design/methodology/approach
This study employs operations research, discrete and continuous optimization, applied mathematical modeling, data analytics, industrial economics and real options theory.
Findings
Constructed stochastic algorithms extend the deterministic economic life method and are compared to the contemporary theory of stochastic asset replacement based on real options and dynamic programming. It is proven that both techniques deliver similar results when the cost volatility is small. A major theoretic finding is that the cost uncertainty speeds up the replacement decision.
Research limitations/implications
This research suggests that the proposed stochastic algorithms may become an important tool for managerial decisions about replacement of many similar machines with detailed data on operating and replacement costs.
Originality/value
Compared to the real options replacement theory, major advantages of the proposed algorithms are that they work equally well for any distribution of age-dependent stochastic operating cost. The algorithms are tested on a real industrial case about replacement of medical imaging devices. Numeric simulation supports obtained analytic outcomes.
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Addresses important logistical considerations in the distribution of a seasonal food product. While most organizations recognize that quality affects both demand and cost, the…
Abstract
Addresses important logistical considerations in the distribution of a seasonal food product. While most organizations recognize that quality affects both demand and cost, the degree of uncertainty in the distribution channel itself, which impacts quality through management’s efforts to procure adequate stock of product during peak demand, must also be considered. Develops a stochastic dynamic programming formulation from which budget‐constrained order quantities may be determined. Shows that the distribution and timing of orders impacts on quality, which is measured by the shortage probability over the multiple period planning horizon. Provides a numerical example from which optimal solutions are obtained. Provides a basic framework from which decision support tools may be developed to assist in procuring a product in a distribution channel where receipt quantities are probabilistic.
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Li Yang, Zhiping Chen and Qianhui Hu
To help investors find an investment policy with strong competitiveness, the purpose of this paper is to construct a multi-period investment decision model with practicality and…
Abstract
Purpose
To help investors find an investment policy with strong competitiveness, the purpose of this paper is to construct a multi-period investment decision model with practicality and superior performance.
Design/methodology/approach
The paper uses a suitable multi-period risk measure to construct a multi-period portfolio selection model, where target returns at intermediate periods and market frictions are taken into account simultaneously. An efficient scenario tree generation approach is proposed in order to transform the complex multi-period portfolio selection problem into a tractable one.
Findings
Numerical results show the new scenario tree generation algorithms are stable and can further reduce the tree size. With the scenario tree generated by the new scenario tree generation approach, the optimal investment strategy obtained under the multi-period investment decision model has more superior performance and robustness than the corresponding optimal investment strategy obtained under the single period investment model or the multi-period investment model only paying attention to the terminal cash flow.
Research limitations/implications
The new risk measure and multi-period investment decision models can stimulate readers to find even better models and to efficiently solve realistic multi-period portfolio selection problems.
Practical implications
The empirical results show the superior performance and robustness of optimal investment strategy obtained with the new models. What's more important, the empirical analyses tell readers how different market frictions affect the performance of optimal portfolios, which can guide them to efficiently solve real multi-period investment decision problems in practice.
Originality/value
The paper first derives the concrete structure of the time consistent generalized convex multi-period risk measure, then constructs a multi-period portfolio selection model based on the new multi-period risk measure, and proposes a new extremum scenario tree generation algorithm. The authors construct a realistic multi-period investment decision model. Furthermore, using the proposed scenario tree generation algorithm, the authors transform the established stochastic investment decision model into a deterministic optimization problem, which can provide optimal investment decisions with robustness and superior performance.
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Jess S. Boronico and Dennis J. Bland
Addresses important logistical considerations in the distribution of a seasonal food product. While continued attempts have been made to maintain high levels of customer service…
Abstract
Addresses important logistical considerations in the distribution of a seasonal food product. While continued attempts have been made to maintain high levels of customer service within the food industry, the degree of uncertainty in the distribution channel itself often undermines management’s efforts to procure adequate stock of product during peak demand season. Develops a stochastic dynamic programming formulation which may serve as a decision‐support tool for managers faced with procuring product in a distribution channel in which receipt quantities are probabilistic. Provides numerical results, supporting the intuitive result that expected costs and the length of the required planning horizon are inversely related to the level of uncertainty in the distribution channel.
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