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Due to today's competitive environment and information boom, companies are concerned about production planning in uncertain conditions. This paper integrates decision-making method with production scheduling model by considering limited resources. In this paper, a new mathematical model is extended for production project scheduling with multiple execution modes. The main aim of the formulation is to plan and schedule real production projects in uncertain environments. A new mixed-integer linear formulation is presented by considering trade-off of cost, time, as well as quality. Cost–time-quality trade-off is extended with the interval information. In the presented model, activity quality could be enhanced by reworking. The interval forms of some parameters, including duration, quality of activities, cost, and total available resources, are obtained by determining weights of experts and aggregating them. The presented group decision-making method is based on a bi-directional projection measure to deal with interval information. Since the mathematical model is multi-objective and some data are interval, a new modified solution method is developed for solving the model. The presented method for both decision-making and mathematical models is investigated by a real-world production project and two datasets to ascertain the accuracy of the model. Finally, an appropriate sensitivity analysis is proposed. [ABSTRACT FROM AUTHOR]

In this paper, the flow of an incompressible fluid is thermally studied. Investigations into the heat transfer process have been conducted in non-Newtonian fluid flows with chemical reactions and heat sources present. The application of this work is the fluid flow around the stretching sheet; fluid flow on a stretching sheet can be applied to polymer extrusion, drawing or plastic films, hot rolling, casting and other engineering problems. The novelty of this paper is that the governing equations have been solved by a new and efficient semi-analytical approach, the Akbari–Ganji method (AGM). In order to investigate the issue, the finite element method (FEM) has also been applied. Comparing the results of problem-solving with the applied methods with the results of the previous research shows a perfect agreement. The results show that the parameters of Hartmann number and interaction improve the velocity profiles. Additionally, for greater Hartmann number values, raising the parameter of interaction decreases the temperature value, but a smaller value has the reverse effect. As the Hartmann number increases, the fluid velocity decreases and it shows that with the increase of electromagnetic force, the velocity of fluid flow decreases. [ABSTRACT FROM AUTHOR]

An investigation is performed in this paper to analyze the nonlinear thermo-electro-mechanical response of long sandwich cylindrical shells with functionally graded porous (FGP) core and thin piezoelectric actuator layers. The FGP core of the sandwich shell is assumed to be temperature- and microstructure-dependent. It is assumed that the sandwich shell is subjected to uniform lateral pressure loading in a thermo-electrical environment. The equilibrium equations of the shell with infinite length are established with the aid of the virtual displacement principle and von Kármán kinematic assumptions. The governing equations are obtained in terms of displacement components based on the first-order shear deformation model of shallow cylindrical shells and the modified couple stress theory. These nonlinear differential equations are analytically solved for a sandwich shell having both the simply-supported and clamped–clamped edge conditions by employing a two-step perturbation technique. Analytical closed-form solutions are determined as a relationship including the load parameter and the mid-span deflection. The comparison examples are made with the existing results in the literature for a simple functionally graded shell, where good agreement is obtained. It is shown that the nonlinear response of the sandwich shell is highly dependent upon the temperature variation, power law index, porosity coefficient, couple stress parameter, piezoelectric layers, and geometrical parameters of the shell. [ABSTRACT FROM AUTHOR]

Background and Objective: Aortoenteric fistula (AEF) is a rare but life-threatening condition. Secondary AEF in patients with a history of aortic surgery with symptoms of sudden gastrointestinal bleeding may occur even without evidence in endoscopy and colonoscopy, and delay in diagnosis and lack of timely surgery may lead to the death of the patient, and it is important to consider it. This study introduces a 60-year-old man with a history of aortic surgery who referred to the Golestan Hospital in Ahvaz with a complaint of acute gastrointestinal bleeding and underwent surgery with the diagnosis of secondary AEF. Case Report: The patient is a 60-year-old man who had a history of Aortobifemoral Bypass surgery three years ago, and was hospitalized in the emergency room due to gastrointestinal bleeding (melena). The patient's heart rate was 110 beats per minute, the patient's systolic blood pressure was 90 mm Hg and diastolic blood pressure was 60 mm Hg (positive tilt test) and the patient's hemoglobin (HB) was 6 g/dl. The patient underwent fluid resuscitation by the gastroenterology service, received pantoprazole, blood and antibiotics, endoscopy and colonoscopy, but no pathological findings were found. A surgical consultation was requested for him, and the patient underwent emergency CT angiography of the abdominal vessels. Due to the prolonged bleeding, unstable hemodynamics and drop in hemoglobin, it was decided to operate the patient with the suspicion of AEF. During the operation, the aorta (in the renal part) was fistulated to the intestines (jejunum, 30 cm from Treitz ligament) through a 5 mm long tract, which was repaired. The day after the operation, the patient was conscious and had stable vital signs, and was discharged the following week with a good general condition. The patient was followed up monthly for one week, three weeks, and then up to six months, which showed normal conditions. Conclusion: Based on the results of this study, AEF should be considered as a rare but fatal diagnosis in a patient with a history of aortic surgery and lower gastrointestinal bleeding and should undergo emergency surgery. [ABSTRACT FROM AUTHOR]

In a cross-docking system, doors can be used exclusively for receiving or sending operations, or they can be flexible enough to be used for both. Flexible doors have gained attention for improving cross-docking system performance, but their implementation incurs additional costs due to the need for dual-function equipment to handle both receiving and sending operations. Despite the advantages of flexible doors, applying them is usually associated with additional costs due to the need for dual-function equipment to receive and send. Moreover, the distance that goods move within crossdocking facilities, from receiving to sending dock doors, significantly affects how well these facilities work. This paper presents a new bi-objective mixed-integer linear programming model for scheduling the inbound and outbound trucks in a cross-docking facility. The model objectives are to minimize total system costs, including additional costs of applying flexible doors and transshipment (maximize efficiency) and to minimize outbound trucks’ tardiness from predetermined due dates (maximize responsiveness). As a result of the uncertainties in cross-dock truck scheduling problems, the parameters are considered triangular interval-valued fuzzy (IVF) numbers. Moreover, a new IVF-uncertain solution approach based on the max-min operator and compromise programming concepts is proposed to solve multi-objective mathematical programming problems with triangular IVF numbers. The proposed model and IVF-solution approach are used for cross-docking operations planning at a well-known food manufacturing group. The results are also analyzed according to their sensitivity to changes in key parameters of the cross-docking problem. Comparison of the proposed approach with other known fuzzy methods for solving multi-objective models demonstrates the superior performance of the proposed approach in the real case study. [ABSTRACT FROM AUTHOR]

Bacteriocins are a kind of antimicrobial peptides that kill or inhibit the growth of bacterial strains. The purpose of this study was to investigate the antibacterial effect of Serratia marcescens on several pathogenic bacterial strains. Bacteriocin produced by S. marcescens was purified by chromatography with Sephadex G-75 column, and its antibacterial effect on gram-negative bacteria, including Escherichia coli ATCC 700928, Pseudomonas aeruginosa PTCC 1707, S. marcescens PTCC 1621, Vibrio fischeri PTCC 1693, and Vibrio harveyi PTCC 1755, were evaluated by the disk diffusion method. The structure of bacteriocin was determined by nuclear magnetic resonance spectroscopy. The interaction of bacteriocin with the antigen 43 (Ag43) of E. coli was evaluated by the molecular docking method. Bacteriocin extracted from bacterial isolates had antibacterial activity on E. coli strains but not on other studied strains. Bioinformatics analysis also showed bacteriocin docking with Ag43 with an energy of -159.968 kJ/mol. Natural compounds, such as bacteriocin, can be an alternative to common chemical compounds and antibiotics. To reach a definite conclusion in this regard, there is a need for further research and understanding of their mechanism of action. [ABSTRACT FROM AUTHOR]