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This study aims to design a supply chain network in an uncertain environment while exists two options for distribution of the perishable product and production lot-sizing is concerned.

Owing to the complexity of the mathematical model, a solution approach based on a Lagrangian relaxation (LR) heuristic is developed which provides good-quality upper and lower bounds.

The model output is discussed through various examples. The introduction of some enhancements and using some heuristics results in better outputs in the solution procedure.

This paper covers the modeling of some real-world problems in which demand is uncertain and managers face making some concurrent decisions related to supply chain management, transportation and logistics and inventory control issues. Furthermore, considering the perishability of product in modeling makes the problem more practically significant as these days there are many supply chains handling dairy and other fresh products.

Considering uncertainty, production, transshipment and perishable product in the inventory-routing problem makes a new variant that has not yet been studied. The proposed novel solution is based on the LR approach that is enhanced by some heuristics and some valid inequalities that make it different from the current version of the LR used by other studies.

Chromium based conversion coatings have been used widely to delay the formation of white rust on galvanized steel sheets. As chromium is carcinogenic, an alternative chromium‐free conversion coating was developed for use on galvanized steel surfaces to delay the onset of white rusting. This paper seeks to address this issue.

The molybdate coating was produced on galvanized steel surface by dipping in a phosphate solution bath using Na₂MoO₄ as a corrosion inhibitor.

The cyclic polarization tests conducted on molybdates‐treated samples showed a wider potential band in 3.5 per cent NaCl solution, indicating that the coating is passivating in nature. The polarization (R_p) of both treated and untreated samples was evaluated in 3.5 per cent NaCl solution by electrochemical impedance spectroscopy (EIS) technique. It was observed that the polarization resistance (R_p) of molybdate treated galvanized sample is 2.3 times higher compared with the untreated one. The improved corrosion resistance also was evident from the simulated salt spray test results where the treated sample showed a five times improvement over the untreated sample.

The corrosion resistance of inorganic‐based chromium‐free conversion coatings has not been equivalent to that of chromium based conversion coatings. A chromium‐free conversion coating with enhanced corrosion performance by using water reducible polymer will be described in a future paper.

The developed chromium‐free passivation solution has been implemented for galvanized tube passivation. It is one of the best alternative chromium‐free chemicals for the prevention of white rust formation on galvanized materials during transit and storage.

This paper describes a new coating system for the galvanized material which will provide a significant improvement to white rusting resistance for the galvanizing industry.

The purpose of this paper is to develop a corrosion resistant zinc‐free coating for interstitial free steel.

The objective was achieved by developing a titania‐silica hybrid coating through a sol‐gel process by incorporating a dye molecule. The role of dye molecules was particularly important for enhancing the anti‐corrosion properties of the coating. The approach of current research was to develop a low‐temperature coating process that can bring similar performance to that obtained in case of zinc coating. Titania and silica precursors were mixed by stirring under a nitrogen atmosphere at 80°C to formulate a low‐temperature coating. The dye molecules were added before addition of water for subsequent hydrolysis. This complete formulation was applied over steel sheets using a roll coater as the application method.

The ranking order of improved corrosion resistance was found to be PATMS>EETMS>GPTMS and the addition of trace amount of tartrazine dye (60‐65 mg/l of liquid) in PATMS increased the corrosion service life in saline environments from 168 to 216 h, thus showing a promising improvement. Scanning Kelvin Probe results indicated that the corrosion reaction is controlled cathodically in presence of dye and, electrochemical impedance spectroscopy results exhibited a charge transfer resistance (Ct) of coating with dye of 419Ω cm², which was higher than that of a similar coating without dye (360Ω cm²), indicating increased corrosion protection.

This coating had improved barrier protection but lacked cut edge protection. Future work will focus on adding sacrificial protection by introducing compatible corrosion inhibitors, especially dye molecules, which are photosensitive.

This coating has huge potential for use in the automotive sector, especially for certain automotive parts (i.e. helm flanges), which suffer from poor durability in salty and high‐humidity atmospheres.

Since this coating formulation utilises a partially aqueous base, some environmental impact cannot be avoided, but it will have less impact than a complete solvent base formulation.

The novelty of the work was the introduction of dye molecules as the corrosion inhibitor and their compatibility in the hybrid coating system.

The aim of this work was to study the effect of La(NO

)

on the corrosion behavior of sol-gel coating prepared by hydrolysis of 3-glycidoxypropyl)methyldiethoxysilane and 3-aminopropyltriethoxysilane. Generally, galvanized steel is subjected to a hexavalent chromium passivation treatment. Hexavalent chromium passivation is not an environment friendly product and researchers are looking for a suitable alternative for chromium passivation treatment. Some of the potential alternatives are silicate conversion coating or the use of silane-based coatings. In this context, sol-gel coating was investigated as a potential replacement for hazardous hexavalent chromium passivation treatment.

The sol-gel film was deposited on galvanized steel sheet by the dip coating method. The molecular vibration and chemical properties of sol-gel solution and coated films were obtained by infrared spectroscopy. Images from a scanning electron microscope were obtained to characterize the morphology of the film. The corrosion resistance of the coated samples was evaluated by electrochemical impedance spectroscopy (EIS), potentiodynamic polarization curves and salt spray tests.

The results indicated that La(NO

)

-doped coatings were more resistance to corrosion than undoped coating. The coating doped with 0.5 per cent La(NO

)

offered improved corrosion protection due to the inhibitive action of the La3+ ion.

This result can provide a reference for the development of chromium-free passivation for galvanized sheeting.

The purpose of the paper is to show the corrosion effect of benzotriazole in comparison with iron phosphate (PFe) coating as a sealer for the PFe layer in carbon steel paint pre-treatment and to show its ecological advantages as a more environment-friendly inhibiting compound than PFe.

Samples of carbon steel (SAE 1010) were phosphated in two baths, one containing iron PFe and PFe and BTAH (PFe + BTAH). Anodic potentiostatic polarization curves and electrochemical impedance spectroscopy were used to evaluate the corrosion resistance of phosphated carbon steel in 0.1 molL−1 H₂SO₄, 0.5 molL−1 NaCl and 0.1 molL−1 NaOH. The phosphate layers obtained were analyzed by infrared spectroscopy. Surface observation by scanning electron microscopy (SEM) showed that the PFe and PFe + BTAH layers are deposited as crystals with granular morphology. The electrochemical results showed that the PFe + BTAH coating was more effective in corrosion protection of the carbon steel.

This paper presents the application of benzotriazole as post-treatment of PFe-coated carbon steel. The results show that benzotriazole improves the phosphate layer properties. The SEM micrographs showed that the layer formed in PFe and PFe + BTAH baths consists of grain-like crystals, and infrared results revealed the BTAH presence in PFe phosphate. The corrosion resistance results showed higher efficiency associated to the PFe + BTAH phosphate layer relative to that of PFe. From the present study, results can be concluded that BTAH can be used as a post-treatment for PFe phosphate coating.

This paper deals with the corrosion resistance and surface carbon steel characterization of a new sealer for PFe coating, which has been prepared for this study and was never tested previously. These are candidate materials for substitution of chromium sealer. The BTAH sealer presents environmental and corrosion resistance advantages when compared with the post-treatment based on chrome. Although BTAH improves PFe layers’ properties, it is the worst phosphate coating. This manuscript has never been previously submitted and deals with original results.

The purpose of this paper is to investigate the corrosion resistance of SiO₂-Al₂O₃ coating on mild steel.

SiO₂-Al₂O₃ was coated using sol-gel method, and electrochemical measurements were applied to assess the performance of the coated steel.

The main conclusion is that SiO₂-Al₂O₃-coated specimens acquired a higher corrosion resistance than that of uncoated specimen. i_corr values of the coated specimens were between 12 and 14 times smaller than those of uncoated specimen. The coated specimens exhibited a higher R_cor value at electrochemical impedance spectroscopy analysis. The high values of R_cor and low values of CPE_dl observed within the SiO₂-Al₂O₃-coated samples imply an improved anti-corrosion capability.

In this work, there are three points of originality. First, steel specimens were coated with ormosil-based solution by applying sol-gel dip coating method. Second, both SiO₂ and Al₂O₃ coatings were applied simultaneously at a considerably low temperature, i.e. 200 °C. Finally, the performance of the coated materials against wet corrosion was improved significantly.

Fluorinated silicon polymers are expected to be adopted in specific coatings to afford outstanding advantages, such as high chemical and photochemical resistance, low surface tension and low refractive index. The modified acrylate resin is prepared via solution polymerization of fluorine and silicon monomers, acrylate monomers and other functional monomers. The purpose of this paper is that the fluorine and silicon monomers such as vinyltriethoxysilane (VTES) and hexafluorobutyl methacrylate (HFMA) and some cheap monomers such as styrene are used to prepare the cationic acrylic resin.

The fluorine and silicon modified cationic acrylic resin is prepared via solution polymerization technology, which uses butyl acrylate (BA), methyl methacrylate (MMA), styrene (St), HFMA, VTES, dimethylaminoethyl methacrylate (DMAEMA) and hydroxypropyl methacrylate (HPMA) as the co-polymerized monomers, propylene glycol monomethyl ether (PGME) as solvent and 2,2-Azo-bis-iso-butyronitrile (AIBN) as the initiator to create a resin to introduce the Si–O and C–F into the polymer chains. The cathodic electrodeposition (CED) coatings were prepared by mixing the synthetic resin and blocked isocyanate.

The influence of the amounts of HFMA and VETS on the resin and the resultant CED coatings is investigated in detail. The optimum amounts of HFMA and VETS are obtained, which is 7–8% and 4–5%, respectively. The hydrophobicity and the acid and alkaline resistance of the film are improved when VETS and HFMA are introduced to co-polymerize with other monomers.

The fluorine and silicon monomers such as VTES and HFMA and some cheap monomers such as styrene, which are used to prepare the cationic acrylic resin, are seldom reported in the open literature.

Security is one of the major challenges in the design and implementation of protocols for mobile ad hoc networks (MANETs). In such systems, the cooperation between nodes is one of the important principles being followed in the current research works to formulate various security protocols. Many existing works assume that mobile nodes will follow prescribed protocols without deviation. However, this is not always the case, because these networks are subjected to a variety of malicious attacks. Since there are various models of attack, trust routing scheme can guarantee security and trust of the network. The purpose of this paper is to propose a novel trusted routing model for mitigating attacks in MANETs.

The proposed model incorporates the concept of trust into the MANETs and applies grey relational analysis theory combined with fuzzy sets to calculate a node’s trust level based on observations from neighbour nodes’ trust level, these trust levels are then used in the routing decision-making process.

In order to prove the applicability of the proposed solution, extensive experiments were conducted to evaluate the efficiency of the proposed model, aiming at improving the network interaction quality, malicious node mitigation and enhancements of the system’s security.

The proposed solution in this paper is a new approach combining the fundamental basics of fuzzy sets with the grey theory, where establishment of trust relationships among participating nodes is critical in order to enable collaborative optimisation of system metrics. Experimental results indicate that the proposed method is useful for reducing the effects of malicious nodes and for the enhancements of system’s security.

This study aims to propose a novel method for the conflict detection and eradication of autonomous vehicles which has predetermined routes to establish multi pickup and delivery tasks according to task priorities and vehicle capacity status on each pickup and delivery nodes in assembly cells in the automotive production.

In the designed system, the routing of autonomous vehicles (AVs) and scheduling of pickup and delivery tasks are established in production logistics. Gantt chart is created according to vehicle routes, and conflicts are detected using the proposed conflict-sweep algorithm. The proposed conflict-solving algorithm eliminates conflicts on intersections and roads by considering vehicle routes and task priorities.

In many production systems, there is a need to obtain flexible routes in each pickup delivery task group that changes during day, week, etc. Proposed system provides remarkable advantages in obtaining conflict-free routes for pre-scheduled multi transport tasks of vehicles by considering efficiency in production systems.

A novel method is proposed for the conflict detection and eradication of AVs. Proposed system eliminates conflicts on intersections and roads by considering pre-planned vehicle routes for a fleet of heterogeneous AVs. Unlike most of the other conflict-free algorithms, in which conflicts are solved between two points, proposed system also considers multi pickup and delivery points for AVs. This is pioneering paper that addresses conflict-free route planning with backhauls and scheduling of multi pickup and delivery tasks for AVs.

The study aims to optimize truck routes by minimizing social and economic costs. It introduces a strategy involving diverse drones and their potential for reusing at DNs based on flight range. In HTDRP-DC, trucks can select and transport various drones to LDs to reduce deprivation time. This study estimates the nonlinear deprivation cost function using a linear two-piece-wise function, leading to MILP formulations. A heuristic-based Benders Decomposition approach is implemented to address medium and large instances. Valid inequalities and a heuristic method enhance convergence boundaries, ensuring an efficient solution methodology.

Research has yet to address critical factors in disaster logistics: minimizing the social and economic costs simultaneously and using drones in relief distribution; deprivation as a social cost measures the human suffering from a shortage of relief supplies. The proposed hybrid truck-drone routing problem minimizing deprivation cost (HTDRP-DC) involves distributing relief supplies to dispersed demand nodes with undamaged (LDs) or damaged (DNs) access roads, utilizing multiple trucks and diverse drones. A Benders Decomposition approach is enhanced by accelerating techniques.

Incorporating deprivation and economic costs results in selecting optimal routes, effectively reducing the time required to assist affected areas. Additionally, employing various drone types and their reuse in damaged nodes reduces deprivation time and associated deprivation costs. The study employs valid inequalities and the heuristic method to solve the master problem, substantially reducing computational time and iterations compared to GAMS and classical Benders Decomposition Algorithm. The proposed heuristic-based Benders Decomposition approach is applied to a disaster in Tehran, demonstrating efficient solutions for the HTDRP-DC regarding computational time and convergence rate.

Current research introduces an HTDRP-DC problem that addresses minimizing deprivation costs considering the vehicle’s arrival time as the deprivation time, offering a unique solution to optimize route selection in relief distribution. Furthermore, integrating heuristic methods and valid inequalities into the Benders Decomposition approach enhances its effectiveness in solving complex routing challenges in disaster scenarios.