با سلام خدمت کاربران در صورتی که با خطای سیستم پرداخت بانکی مواجه شدید از طریق کارت به کارت مقاله خود را دریافت کنید (تا مشکل رفع گردد). با تشکر از صبوری شما!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
A Multi-Objective Green Hub Location Problem with Multi Item-Multi Temperature Joint Distribution for Perishable Products in Cold Supply Chain
یک مشکل مکان یابی Green Hub چند هدفه با توزیع مشترک چند ماده ای - چند دما برای محصولات فاسدشدنی در زنجیره تامین سرد-2021
This paper investigates a bi-objective green hub location problem, in which multiple perishable products with various storage temperatures can be distributed simultaneously in a cold supply chain (CSC). The objectives of this problem include minimizing the system’s total cost (including transportation, hub establishment, adjustment of the storage compartments’ temperatures, and carbon emission costs) and maximizing the quality of the delivered product to the customer via the proposed model. Mixed-integer linear programming (MILP) in the GAMS software was employed to formulate this problem. Then, the ε-Constraint method was adopted to solve the presented bi-objective model to obtain the Pareto frontier and consequently, a numerical example based on the CAB (Civil Aeronautics Board) database is presented to validate the applicability of the model. The solutions of the model provide information regarding the hub location (HL), allocating customers to the hubs, allocating customers to the vehicles, and the sequence of vehicles’ services for the Multi Item-Multi Temperature Joint Distribution of perishable products in CSCs. Moreover, the final results revealed the existence of a contradictory exchange between the two objectives of this paper, implying that the higher is the quality of the delivered perishable product to the customer, the greater is the system’s total cost. The novelty of the proposed model compared to other hub location problems (HLPs) lies in the integration of the tactical/operational decisions with strategic decisions to provide logistic solutions in CSCs by considering the carbon emissions as an environmental factor in the transportation systems for the simultaneous distribution of dissimilar storage temperatures perishable products within a CSC. The proposed model in this research can help the distributers of perishable products by maintaining the quality of the delivered items and reducing the system’s total costs and considering the carbon emissions of transportation systems. This study has practical implications for the logistics and CSCs managers to not only establish a distribution network for multiple perishable products on the basis of the findings, but also respond to the environmental sustainability.
Keywords: Hub Location | Perishable Products | Cold Supply Chain | Transportation | Multi-objective
Multi-party coordination in sustainable supply chain under consumer green awareness
هماهنگی چند جانبه در زنجیره تأمین پایدار تحت آگاهی سبز مصرف کننده-2021
The rapid growth of the green market in recent years has motivated manufacturing companies to operate carbon abatement schemes for better sustainability. This paper investigates sustainability coordination among three major supply chain parties in the context of consumer green awareness by applying a Stackelberg game model. Instead of considering the manufacturer as the only party to operate carbon management schemes, this paper examines a model in which both the supplier and the manufacturer embark on green investment under make-to-order production. Meanwhile, the retailer considers the influence of green consumers on the demand rate and determines the order quantity for the manufacturer. This paper analyses the sustainability and profitability performance of the supply chain under centralised and decentralised scenarios, and applies the quantity discount and cost-sharing contracts to improve supply chain performance. It is shown that greener markets are more profitable and Pareto improvement can be achieved for all parties under a quantity discount contract. High investment cost hinders the company from achieving a higher emission reduction level. Further, increased consumer green awareness can motivate companies to achieve a higher emission reduction level, but not always lead to improved total carbon emission reductions resulting from the increase in product demand caused by green awareness. It also shows the importance of involving suppliers in green investment, due to their high carbon emission during the component production processes. The findings of this research provide theoretical support for supply chain parties to achieve better coordination in balancing profitability and carbon abatement.
Keywords: Multi-party supply chain | Newsvendor model | Stackelberg game | Consumer green awareness | Sustainability development
Carbon reduction decisions under progressive carbon tax regulations: A new dual-channel supply chain network equilibrium model
تصمیمات مربوط به کاهش کربن تحت مقررات مالیاتی پیش رونده کربن: مدل تعادل شبکه زنجیره تامین جدید دو کاناله-2021
Since the production process in manufacturing industry is one of the main sources of carbon emissions, most governments have enacted relevant carbon policies to encourage manufacturers to invest in green production technology and reduce carbon emissions. However, the effectiveness of the carbon policy deserves further investigation because the manufacturers focus more on economic profits in actual operations. For this purpose, this paper proposes a dual-channel supply chain network (DCSCN) equilibrium model based on variational inequality theory to examine progressive carbon tax mechanism design of the government and its impacts on the production/pricing and abatement level decisions of the manufacturers in the DCSCN. In addition, this paper also examines the influences of the online channel introduction on supply chain network equilibrium decisions, carbon emissions and profits. We employ the modified projection and contraction algorithm to obtain the numerical solutions for several examples, and analyze the impacts of the key parameters on the equilibrium decisions and derive several managerial insights. The results show that if the government sets the high-level carbon tax and the cut-off value in progressive carbon tax policy appropriately, it can induce the manufacturers to improve abatement level actively; meanwhile the profit maximization goal of the manufacturer and the whole DCSCN can be consistent with the government’s low-carbon emission target. Moreover, the introduction of online channel may depress the economic activities and lead to profit loss for the supply chain network but contributes to reducing the carbon emissions under progressive carbon tax policy. The conclusions may be useful for reference in the study of the low-carbon supply chain and the design of carbon emission reduction policy for government.
Keywords: Dual-channel supply chain network | Progressive carbon tax | Product abatement level | Variational inequality theory
Circular economy for phosphorus supply chain and its impact on social sustainable development goals
اقتصاد مدور برای زنجیره تأمین فسفر و تأثیر آن بر اهداف توسعه پایدار اجتماعی-2021
To be able to grow crops, we have interfered with Earths reserves of one of top three essential elements, phosphorus (P), as to which we face a problem related to its high consumption compared to available resources. This forces us to follow the alternative of closing the phosphorus loop from a circular economy perspective. However, there is a lack of research on regional and global social sustainability in this area, as emphasized in the United Nations Agenda 2030 goals for sustainable development. In this paper, we address social challenges involved in global phosphorus supply chain, such as eradicating poverty, child labor and malnutrition; promoting gender equality; providing decent work and economic growth; maintaining sustainable water use; and achieving food security. Our research is driven by the question of whether the circular economy aims to direct phosphorus management towards tackling social issues associated with its supply chain. We use system dynamics modelling by combining the concept of material flow analysis and social life cycle assessment. Detailed analysis at regional and global levels indicates a paradoxical social impact of phosphorus circular model. This reflects the multiple stakeholders involved, and the regional interactions with phosphorus circular economy transitions. Improvements can be demonstrated in reducing poverty and providing safer work environment in many regions, e.g., Western Asia (93%), New Zealand, Central Asia, and Europe (44–61%), while achieving employment targets is limited in Northern and Eastern Europe. Circular model fails to promote gender equality, it also exacerbates exploitative child work problem for the Caribbean and most Africa. It provides sufficient nutrition to North America, Australia/New Zealand, and Northern Europe. It achieves water use targets in several regions with 53% savings worldwide. Finally, circular model contributes to P efficiency (average balance of 1.21 kgP/ha) and strengthens P security within most regions with an average of 64%.
Keywords: Critical materials | Phosphorus | Social sustainability | Circular economy | Dynamic modelling
Reimagining the milk supply chain: Reusable vessels for bulk delivery
Reimagining زنجیره تامین شیر: ظروف قابل استفاده مجدد برای تحویل به صورت عمده-2021
Milk packaging has been analysed multiple times in pursuit of ﬁnding the most appropriate vessel from an environmental point of view. Research has concentrated on commercially available containers of 0.5 –2.5 litres, usually made from High-Density Polyethylene (HDPE), Polyethylene Terephthalate (PET), paper- based cartons, or glass, with some studies considering a reuse scheme for glass bottles. Whilst applicable for household delivery, such a reuse scheme is not practical for delivery to cafés where large volumes of milk are used every day; little information is known about transportation of bulk volumes of milk in bigger vessels such as steel churns. This study compares a proposed milk supply chain using a mix of reusable stainless steel churns and reusable glass bottles with the current supply chain that uses single- use HDPE bottles, for transportation of milk to 10 cafés belonging to The University of Sheﬃeld. A cradle- to-grave life cycle assessment (LCA) is conducted using data obtained from the university and Our Cow Molly, a local dairy farm which delivers milk to the university. Sensitivity analysis was performed around the recycling rate of plastic bottles, water consumption for churn cleaning, the reuse rate of glass bottles and churns and the source of the on-farm electricity. The study suggests that the greenhouse gas emission can be lowered by approx. 6.5 tons of CO2 equivalent annually if the reuse scheme is applied (this equates to a 65% reduction for the processes analysed). Considerable savings are also reported in cate- gories such as water consumption, fossil resources depletion and cumulative energy demand. The reuse scheme is, however, likely to induce a similar or higher mineral resource use and higher environmental damage in the marine eutrophication category due to water treatment. Production of plastic bottles in the plastic scenario and maintenance and transport on the reusable side are the main contributors to the environmental impact. Further improvements in the reuse scenario could be achieved by reducing the amount of water used for cleaning and hence the electricity demand for water heating. The reuse scheme could also beneﬁt environmentally from using an electric refrigerated van instead of a diesel vehicle.© 2021 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.
Keywords: Life cycle assessment | Milk | Reuse | Plastic | Impact assessment | Carbon footprint
Environmental impacts of animal-based food supply chains with market characteristics
تأثیرات زیست محیطی زنجیره های تأمین مواد غذایی حیوانی با ویژگی های بازار-2021
Animal-based food supply chains lead to significant environmental impacts, which can be influenced by production systems, distribution networks and consumption patterns. To develop strategy aimed at reducing the environmental impact of animal-based food supply chains, the common environmental hotspots among different types of food, the role of transport logistics and the consequence of end market need to be better understood. Life cycle assessment was adopted to model three types of animal-based food chains (beef, butter and salmon), with specific technologies, high spatial-resolution logistics and typical consumption patterns for three markets: local, regional (intra-European) and international. The results confirmed that the farm production stage usually had the greatest environmental impact, except when air transport was used for distribution. Potentially, the role of end market also can significantly influence the environmental impacts. To understand more, three improvement options were examined in detail with regard to hotspots for climate change: novel feed ingredients (farm production stage), sustainable aviation fuel (transport and logistics stage) and reduction of wasted food (consumption and end of life stage). Significant reduction was achieved in the salmon system by sustainable aviation fuel (64%) and novel feed (15%). Minimizing food waste drove the greatest reduction in the beef supply chain (23%) and the international butter supply chain can reduce 50% of GHG mission by adopting sustainable aviation fuel. Combined interventions could reduce GHG emission of animal-based food supply chains by 15% to 82%, depending on market, transport and food waste behaviour. The results show that ecoefficiency information of animal-based foods should include the full supply chain. The effective mitigation strategy to achieve the greatest reduction should not only consider the impacts on-farm, but also detail of the downstream impacts, such as food distribution network and consumption patterns.
Keywords: Sustainability | Life cycle analysis | Animal-based food supply chain | Spatial-resolution
A life cycle sustainability assessment of organic and conventional pork supply chains in Sweden
ارزیابی پایداری چرخه زندگی زنجیره های تامین گوشت خوک آلی و معمولی در سوئد-2021
Most existing life cycle assessment studies that have compared the sustainability of organic and conventional pork supply chains are environmental assessments. The economic and social sustainability dimensions of pork supply chains are currently under-researched. The study reported here was designed to assess the environmental, economic and social sustainability of conventional and organic pork in Sweden. Life Cycle Sustainability Assessment was undertaken using 20 indicators expressed per unit product (1000 kg pork fork weight) and per unit area (1000 ha of farmland) for the four main subsystems in pork supply chains: (1) farm and feed production, (2) slaughter, (3) wholesaling and retailing, and (4) consumption. The organic pork supply chain out-performed the conventional chain in 11 of the 20 indicators expressed per unit product and 18 of the 20 indicators expressed per unit area. It was therefore the more sustainable of the two chains in nearly all the indicators expressed per unit area. However, the organic supply chain was less sustainable in some of the indicators expressed per unit product because, more feed per kg of pork was required in organic pork production. Pig welfare improvement leads to higher production costs and environmental impacts. Assessment of all three sustainability dimensions – environmental, economic and social – helps to identify trade-offs between these three pillars of sustainability. However, the selection of indicators influences results, and obtaining environmental, economic and social data simultaneously is challenging.
Keywords: Life cycle sustainability assessment | Environmental life cycle assessment | Life cycle costing | Social life cycle assessment | Organic pork supply chain | Conventional pork supply chain
Mapping spatial supply chain paths for embodied water flows driven by food demand in China
نقشه برداری از مسیرهای زنجیره تأمین فضایی برای جریان های آب تجسم یافته ناشی از تقاضای مواد غذایی در چین-2021
Identifying critical spatial supply chain paths for embodied water flows driven by food demand can guide the development of more spatially explicit food-related policies for water savings. Previous studies have quantified water uses caused by food demand, but overlook intermediate transfer paths within and among regions. That is, spatial supply chain paths describing step-by-step transfer stages between water uses and final food demand have not been well characterized. Based on the multi-regional input-output model and structural path analysis, this study exhaustively identifies critical spatial supply chain paths for provincial water withdrawals driven by final food demand in China. Results show that the final demand of food products from critical sectors (e.g., agricultural products processing, rice, and swine) and regions (e.g., Xinjiang, Heilongjiang, and Guangdong) drives large amounts of water withdrawals. Critical supply chain paths indicate that agricultural products processing, food manufacturing, and catering should pay special attention to increasing the use efficiency of rice, poultry, cotton, water, and gas products, which can effectively reduce national water withdrawals. The interregional paths further provide evidence for interregional cooperation to save food-related water resources, such as the transfer of capital and technologies from agricultural products processing in Shandong to cotton production in Xinjiang and rice production in Heilongjiang. These critical supply chain paths provide spatially explicit and targeted hotspots for demand-side policies. They can also serve for the evaluation of measures in each stage of the supply chain paths.
Keywords: Food-water nexus | Input-output analysis | Structural path analysis | Supply chains | Consumption
Moving towards circular bioeconomy: Managing olive cake supply chain through contracts
حرکت به سمت اقتصاد زیستی دایره ای: مدیریت زنجیره تامین کیک زیتون از طریق قراردادها-2021
Circular bioeconomy represents a recent political vision expected to contribute in tackling the main challenges faced when sustainable industrial transition trajectories are to be implemented. Coordination and interdependence among actors are crucial steps for value creation when developing new sustainable supply chains. Current study is based on a choice experiment devised with contract design theory applied to a specific supply chain in which a circular bioeconomy strategy is implemented. It investigates the propensity of Sicilian millers to participate in a novel supply chain in which feedstuff is produced by processing a by-product, namely olive cake. Furthermore, millers contract attributes’ preferences are analysed. The results from two econometric models reveal that 71% of the interviewed entrepreneurs would participate in the proposed supply chain while the propensity to participate is positively related with firm size and millers’ attitudes but decreases if millers experienced previous investments or have previously participated in cooperatives. Moreover, respondents prefer shorter length of contract, with a minimum guarantee price, with a renegotiation option, and without the obligation of a minimum volume of product to be supplied. Contract agreements, when contract characteristics are designed ad hoc, are proved to be effective tools for circular bioeconomy supply-chain development.
Keywords: Circular bioeconomy | Supply chain management | Olive cake | Contract design
Optimization of extended business processes in digital supply chains using mathematical programming
بهینه سازی فرآیندهای تجاری گسترده در زنجیره های تأمین دیجیتال با استفاده از برنامه ریزی ریاضی-2021
We propose a mathematical programming approach to optimize the business process transactions in digital supply chains. Five scheduling models from the Process Systems Engineering (PSE) area are applied to schedule the processing of orders in a simplified Order-To-Cash (OTC) business process, which is modeled as a multistage network with parallel units (agents). Two case studies are presented to compare the performance of the scheduling models on various sizes of a flexible jobshop representation of the OTC process. The models are compared and scaled to select those that are more suitable to this application. The continuous-time general precedence model provides an accurate representation of the real system and performs well for small instances. The discrete-time State-Task Network (STN), however, proves most efficient in terms of tractability, despite the well-known limitations resulting from discretizing time. The tightness of the linear programming (LP) relaxations in the discrete-time STN framework, as well as the ability of commercial solvers to perform preprocessing and apply heuristics to the STN formulation, enables finding near optimal solutions quickly even for larger instances.
Keywords: Business process optimization | digital supply chain | order-to-cash | scheduling | mathematical programming