310 research outputs found
Development of a hybrid metaheuristic for the efficient solution of strategic supply chain management problems: application to the energy sector
Supply chain management (SCM) addresses the strategic, tactical, and operational
decision making that optimizes the supply chain performance. The
strategic level defines the supply chain configuration: the selection of suppliers,
transportation routes, manufacturing facilities, production levels, technologies.
The tactical level plans and schedules the supply chain to meet
actual demand. The operational level executes plans. Tactical and operational
level decision-making functions are distributed across the supply
chain.
To increase or optimize performance, supply-chain functions must be
perfectly coordinated. But the cycles of the enterprise and the market make
this difficult: raw material does not arrive on time, production facilities
fail, workers are ill, customers change or cancel orders, therefore, causing
deviations from the plan. In some cases, these situations may be dealt
with locally. In other cases, the problem cannot be âlocally containedâ and
modifications across many functions are required. Consequently, the supply
chain management system must coordinate the revision of plans or schedules.
The ability to better understand an algorithm is important to focus on the
following variables: tactical and operational levels of the supply chain so that
the timely dissemination of information, accurate coordination of decisions,
and management of actions among people and systems is achieved ultimately determines the efficient, coordinated achievement of enterprise goal
Cell Production System Design: A Literature Review
Purpose In a cell production system, a number of machines that differ in function are housed in the same cell. The task of these cells is to complete operations on similar parts that are in the same group. Determining the family of machine parts and cells is one of the major design problems of production cells. Cell production system design methods include clustering, graph theory, artificial intelligence, meta-heuristic, simulation, mathematical programming. This article discusses the operation of methods and research in the field of cell production system design.
Methodology: To examine these methods, from 187 articles published in this field by authoritative scientific sources, based on the year of publication and the number of restrictions considered and close to reality, which are searched using the keywords of these restrictions and among them articles Various aspects of production and design problems, such as considering machine costs and cell size and process routing, have been selected simultaneously.
Findings: Finally, the distribution diagram of the use of these methods and the limitations considered by their researchers, shows the use and efficiency of each of these methods. By examining them, more efficient and efficient design fields of this type of production system can be identified.
Originality/Value: In this article, the literature on cell production system from 1972 to 2021 has been reviewed
Development of a hybrid metaheuristic for the efficient solution of strategic supply chain management problems: application to the energy sector
Supply chain management (SCM) addresses the strategic, tactical, and operational
decision making that optimizes the supply chain performance. The
strategic level defines the supply chain configuration: the selection of suppliers,
transportation routes, manufacturing facilities, production levels, technologies.
The tactical level plans and schedules the supply chain to meet
actual demand. The operational level executes plans. Tactical and operational
level decision-making functions are distributed across the supply
chain.
To increase or optimize performance, supply-chain functions must be
perfectly coordinated. But the cycles of the enterprise and the market make
this difficult: raw material does not arrive on time, production facilities
fail, workers are ill, customers change or cancel orders, therefore, causing
deviations from the plan. In some cases, these situations may be dealt
with locally. In other cases, the problem cannot be âlocally containedâ and
modifications across many functions are required. Consequently, the supply
chain management system must coordinate the revision of plans or schedules.
The ability to better understand an algorithm is important to focus on the
following variables: tactical and operational levels of the supply chain so that
the timely dissemination of information, accurate coordination of decisions,
and management of actions among people and systems is achieved ultimately determines the efficient, coordinated achievement of enterprise goal
A multi-agent optimisation model for solving supply network configuration problems
Supply chain literature highlights the increasing importance of effective supply network configuration decisions that take into account such realities as market turbulence and demand volatility, as well as ever-expanding global production networks. These realities have been extensively discussed in the supply network literature under the structural (i.e., physical characteristics), spatial (i.e., geographical positions), and temporal (i.e., changing supply network conditions) dimensions. Supply network configuration decisions that account for these contingencies are expected to meet the evolving needs of consumers while delivering better outcomes for all parties involved and enhancing supply network performance against the key metrics of efficiency, speed and responsiveness. However, making supply network configuration decisions in the situations described above is an ongoing challenge.
Taking a systems perspective, supply networks are typically viewed as socio-technical systems where SN entities (e.g., suppliers, manufacturers) are autonomous individuals with distinct goals, practices and policies, physically inter-connected transferring goods (e.g., raw materials, finished products), as well as socially connected with formal and informal interactions and information sharing. Since the structure and behaviour of such social and technical sub-systems of a supply network, as well as the interactions between those subsystems, determine the overall behaviour of the supply network, both systems should be considered in analysing the overall system
Improving the sustainability of coal SC in both developed and developing countries by incorporating extended exergy accounting and different carbon reduction policies
In the age of Industry 4.0 and global warming, it is inevitable for decision-makers to change the way they view the coal supply chain (SC). In nature, energy is the currency, and nature is the source of energy for humankind. Coal is one of the most important sources of energy which provides much-needed electricity, as well as steel and cement production. This manuscript-based PhD thesis examines the coal SC network as well as the four carbon reduction strategies and plans to develop a comprehensive model for sustainable design. Thus, the Extended Exergy Accounting (EEA) method is incorporated into a coal SC under economic order quantity (EOQ) and economic production quantity (EPQs) in an uncertain environment. Using a real case study in coal SC in Iran, four carbon reduction policies such as carbon tax (Chapter 5), carbon trade (Chapter 6), carbon cap (Chapter 7), and carbon offset (Chapter 8) are examined. Additionally, all carbon policies are compared for sustainable performance of coal SCs in some developed and developing countries (the USA, China, India, Germany, Canada, Australia, etc.) with the world's most significant coal consumption. The objective function of the four optimization models under each carbon policy is to minimize the total exergy (in Joules as opposed to Dollars/Euros) of the coal SC in each country. The models have been solved using three recent metaheuristic algorithms, including Ant lion optimizer (ALO), Lion optimization algorithm (LOA), and Whale optimization algorithm (WOA), as well as three popular ones, such as Genetic algorithm (GA), Ant colony optimization (ACO), and Simulated annealing (SA), are suggested to determine a near-optimal solution to an exergy fuzzy nonlinear integer-programming (EFNIP). Moreover, the proposed metaheuristic algorithms are validated by using an exact method (by GAMS software) in small-size test problems. Finally, through a sensitivity analysis, this dissertation compares the effects of applying different percentages of exergy parameters (capital, labor, and environmental remediation) to coal SC models in each country. Using this approach, we can determine the best carbon reduction policy and exergy percentage that leads to the most sustainable performance (the lowest total exergy per Joule). The findings of this study may enhance the related research of sustainability assessment of SC as well as assist coal enterprises in making logical and measurable decisions
Resolving forward-reverse logistics multi-period model using evolutionary algorithms
© 2016 Elsevier Ltd In the changing competitive landscape and with growing environmental awareness, reverse logistics issues have become prominent in manufacturing organizations. As a result there is an increasing focus on green aspects of the supply chain to reduce environmental impacts and ensure environmental efficiency. This is largely driven by changes made in government rules and regulations with which organizations must comply in order to successfully operate in different regions of the world. Therefore, manufacturing organizations are striving hard to implement environmentally efficient supply chains while simultaneously maximizing their profit to compete in the market. To address the issue, this research studies a forward-reverse logistics model. This paper puts forward a model of a multi-period, multi-echelon, vehicle routing, forward-reverse logistics system. The network considered in the model assumes a fixed number of suppliers, facilities, distributors, customer zones, disassembly locations, re-distributors and second customer zones. The demand levels at customer zones are assumed to be deterministic. The objective of the paper is to maximize the total expected profit and also to obtain an efficient route for the vehicle corresponding to an optimal/near optimal solution. The proposed model is resolved using Artificial Immune System (AIS) and Particle Swarm Optimization (PSO) algorithms. The findings show that for the considered model, AIS works better than the PSO. This information is important for a manufacturing organization engaged in reverse logistics programs and in running units efficiently. This paper also contributes to the limited literature on reverse logistics that considers costs and profit as well as vehicle route management
Meta-heuristic based Construction Supply Chain Modelling and Optimization
Driven by the severe competition within the construction industry, the necessity of improving and optimizing the performance of construction supply chain has been aroused. This thesis proposes three problems with regard to the construction supply chain optimization from three perspectives, namely, deterministic single objective optimization, stochastic optimization and multi-objective optimization respectively. Mathematical models for each problem are constructed accordingly and meta-heuristic algorithms are developed and applied for resolving these three problems
A robust solving strategy for the vehicle routing problem with multiple depots and multiple objectives
This document presents the development of a robust solving strategy for the Vehicle Routing Problem with Multiple Depots and Multiple Objectives (MO-MDVRP). The problem tackeled in this work is the problem to minimize the total cost and the load imbalance in vehicle routing plan for distribution of goods. This thesis presents a MILP mathematical model and a solution strategy based on a Hybrid Multi- Objective Scatter Search Algorithm. Several experiments using simulated instances were run proving that the proposed method is quite robust, this is shown in execution times (less than 4 minutes for an instance with 8 depots and 300 customers); also, the proposed method showed good results compared to the results found with the MILP model for small instances (up to 20 clients and 2 depots).MaestrĂaMagister en IngenierĂa Industria
- âŠ