The Three-Objective Optimization Model of Flexible Workshop Scheduling Problem for Minimizing Work Completion Time, Work Delay Time, and Energy Consumption

In recent years, the optimal design of the workshop schedule has received much attention with the increased competition in the business environment. As a strategic issue, designing a workshop schedule affects other decisions in the production chain. The purpose of this thesis is to design a three-objective mathematical model, with the objectives of minimizing work completion time, work delay time and energy consumption, considering the importance of businesses attention to reduce energy consumption in recent years. The developed model has been solved using exact solution methods of Weighted Sum (WS) and Epsilon Constraint (Ɛ) in small dimensions using GAMS software. These problems were also solved in large-scale problems with NSGA-II and SFLA meta-heuristic algorithms using MATLAB software in single-objective and multi-objective mode due to the NP-Hard nature of this group of large and real dimensional problems. The standard BRdata set of problems were used to investigate the algorithms performance in solving these problems so that it is possible to compare the algorithms performance of this research with the results of the algorithms used by other researchers. The obtained results show the relatively appropriate performance of these algorithms in solving these problems and also the much better and more optimal performance of the NSGA-II algorithm compared to the performance of the SFLA algorithm

Fuzzy Robust Optimization in Closed-Loop Supply Chain Network Model for Hazardous Products (Lead-Acid Battery)

Purpose: This paper models a closed-loop supply chain network problem for hazardous products in the face of demand uncertainty and variable costs. The designed model includes a set of suppliers, production centers, distribution, recycling, disposal, collection and end customers in which strategic and tactical decisions are made simultaneously. Among the decisions made in this paper is the location of production, distribution and collection centers and determining the optimal amount of product flow between the levels of the supply chain network. Methodology: In this paper, the Epsilon constraint method is used to solve a multi-objective model in GMAS software. This article also uses uniform data to solve the problem. Findings: The results of solving the model with fuzzy robust optimization method show that with increasing the uncertainty rate and also reducing the transfer time of hazardous products, the total network costs as well as the amount of greenhouse gas emissions have increased. Also, the study of Pareto front to optimize the total design costs and the amount of greenhouse gas emissions shows that by reducing the amount of greenhouse gas emissions in the network, the costs related to location and routing increase. Originality/Value: In this paper a fuzzy robust optimization is used in closed-loop supply chain network model for hazardous products (Lead-Acid Battery)

Dextran Hydrogels Incorporated with Bioactive Glass-Ceramic: Nanocomposite Scaffolds for Bone Tissue Engineering

A series of nanocomposite scaffolds comprised of dextran (Dex) and sol–gel derived bioactive glass ceramic nanoparticles (nBGC: 0–16 (wt%)) were fabricated as bioactive scaffolds for bone tissue engineering. Scanning electron microscopy showed Dex/nBGC scaffolds were consisting of a porous 3D microstructure with an average pore size of 240 μm. Energy-dispersive x-ray spectroscopy illustrated nBGC nanoparticles were homogenously distributed within the Dex matrix at low nBGC content (2 wt%), while agglomeration was observed at higher nBGC contents. It was found that the osmotic pressure and nBGC agglomeration at higher nBGC contents leads to increased water uptake, then reduction of the compressive modulus. Bioactivity of Dex/nBGC scaffolds was validated through apatite formation after submersion in the simulated body fluid. Dex/nBGC composite scaffolds were found to show improved human osteoblasts (HOBs) proliferation and alkaline phosphatase (ALP) activity with increasing nBGC content up to 16 (wt%) over two weeks. Owing to favorable physicochemical and bioactivity properties, the Dex/nBGC composite hydrogels can be offered as promising bioactive scaffolds for bone tissue engineering applications

Mathematical Modeling of Oxygen Transfer in Porous Scaffolds for Stem Cell Growth: The Effects of Porosity, Cell Type, Scaffold Architecture and Cell Distribution

Oxygen plays a key role in human mesenchymal stem cell growth. Without adequate oxygen (hypoxic condition), cells are not able to survive, proliferate, and migrate. The objective of the present study is to investigate oxygen transfer through the cell-seeded scaffolds stored in static or dynamic bioreactors using a mathematical model. The effects of porosity, cell type, scaffold architecture and cell distribution as potential effective parameters on oxygen transfer kinetics were examined. The results suggest the substantial effect of porosity and cell type on the oxygen concentration within the scaffold compared to scaffold architecture (homogeneous vs. gradient). The obtained data show that the direction of oxygen transfer in deep regions with dead cells changes over time and reverse mass transfer allows the cells to nourish from both top and bottom layers. Finally, the extent of oxygen transfer in static bioreactors/cultures was compared to dynamic ones. The results show that dynamic bioreactors have a better performance and are more efficient for oxygen transfer

The Effect of Investor Sentiment on Betting Against Beta: A SEM Approach Towards Beta Anomaly

Beta anomaly is one of the greatest anomalies in finance literature as CAPM conveys a positive relationship between the beta of a stock and future returns; however, empirical studies do not document this proposition. Branded as betting against beta, this conundrum is known as a controversial subject. Drawing on literature the authors propose new multi-factor models to develop our understanding of betting against beta using investor sentiment as well as Structural Equation Modeling methodology to gauge the models in the presence of the top-down approach. Results indicate that investor sentiment provides a good explanation of the betting against beta. Limitation and future research directions are presented at the end of paper. Keywords: Behavioral finance, Investor sentiment, BAB factor JEL Classifications: G02, G1

Hydrogen Peroxide Preconditioning Promotes Protective Effects of Umbilical Cord Vein Mesenchymal Stem Cells in Experimental Pulmonary Fibrosis

Purpose Idiopathic pulmonary fibrosis (IPF) is a progressive lung disorder with few available treatments. Mesenchymal stem cell therapy (MSCT), an innovative approach, has high therapeutic potential when used to treat IPF. According to recent data, preconditioning of MSCs can improve their therapeutic effects. Our research focuses on investigating the anti-inflammatory and antifibrotic effects of H2O2-preconditioned MSCs (p-MSCs) on mice with bleomycin-induced pulmonary fibrosis (PF). Methods Eight-week-old male C57BL/6 mice were induced with PF by intratracheal (IT) instillation of bleomycin (4 U/kg). Human umbilical cord vein-derived MSCs (hUCV-MSCs) were isolated and exposed to a sub-lethal concentration (15 pM for 24 h) of H2O2 in vitro. One week following the injection of bleomycin, MSCs or p-MSCs were injected (IT) into the experimental PF. The survival rate and weight of mice were recorded, and 14 days after MSCs injection, all mice were sacrificed. Lung tissue was removed from these mice to examine the myeloperoxidase (MPO) activity, histopathological changes (hematoxylin-eosin and Masson\u27s trichrome) and expression of transforming growth factor beta 1 (TGF-β1) and alpha-smooth muscle actin (α-SMA) through immunohistochemistry (IHC) staining. Results Compared to the PF+MSC group, p-MSCs transplantation results in significantly decreased connective tissue () and collagen deposition. Additionally, it is determined that lung tissue in the PF+pMSC group has increased alveolar space () and diminished expression of TGF-β1 and α-SMA. Conclusion The results demonstrate that MSCT using p-MSCs decreases inflammatory and fibrotic factors in bleomycin-induced PF, while also able to increase the therapeutic potency of MSCT in IPF

Reinstating Reality: David Foster Wallace's Short Stories: A Reading According to Jean Baudrillard

This thesis attempts to read David Foster Wallace?s Oblivion Stories from the perspective of Jean Baudrillard. Wallace is well-known for his treatment of boredom, self-consciousness, and loneliness in the contemporary world. However, Baudrillard offers a powerful toolbox to reinstate the reality of Oblivion Stories by foregrounding the silences and pointing to fissures, gaps, and unnoticed interrelations in the eight short stories.Baudrillard uses Marcel Mauss?s concept of "gift exchange" to establish his framework of "symbolic exchange". This concept is expanded and explained in "Another Pioneer". The reciprocal aspect of symbolic exchange of gifts is used to study the division of subject and object as a site for creation of needs in the collection.The accidental death of the infant in "Incarnations of Burned Children" and the suicide of "Good Old Neon" are juxtaposed to analyze different manifestations of the concept of ?eternity?. Besides, the question of terror in "Mister Squishy" and "The Suffering Channel" is analyzed in terms of extreme examples of symbolic challenge.Baudrillard?s conception of the third order of simulacrum and hyperreality is used to look at "Mister Squishy" and "The Suffering Channel". In this light, the arbitrariness of the relation between signifier and signified becomes a basis to study the floatation of liberated signs such as "change", "labor", and lighter signs such as "fashion" in Wallace?s collection. The concept of "simulation" becomes central to the dream sequence of the classroom shooting in "The Soul is Not a Smithy" and the question of mental illness in "Good Old Neon". Finally, in "The Suffering Channel", reality television is seen as an example diffusion of models into reality