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Supplier selection is a complex decision that involves not only the consideration of unit purchasing cost but also product life-cycle cost (LCC), which affects the company’s after-sale costs over the life cycles of their products. Product structure and its impact on the supplier selection evaluation process are rarely investigated in the literature. Therefore, product structure for a multi-criteria multi-product supplier selection problem with uncertainty is considered. In the model, we address product structure, the competitive supply environment, diverse criteria, and standard requirements. The objective is to choose suppliers that minimize LCC and maximize the reliability of the finished products.

Our model provides straightforward representation of interrelationships among multi-objectives and analysis of tradeoffs among conflicting objectives affected by product structure. We illustrate our model by using real life data from lubrication systems in the offshore reliability data (OREDA) handbook. Sensitivity analysis is provided for the case study in which various scenarios that describe product structure, the uncertainties in purchasing prices, reliabilities of purchased components, machine down-time due to poor quality components, suppliers’ capacity and delivery times. Different priority ranking among objectives is also tested to examine the impact of each objective on the overall objective.

Our computational results are based on real data and would provide useful guidelines for the management in OEM to choose right suppliers.

Product structure and its impact on the supplier selection evaluation process are rarely investigated in the literature. Therefore, product structure for a multi-criteria multi-product supplier selection problem with uncertainty is considered.

Expert systems are computer-based systems that mimic the logical processes of human experts or organizations to give advice in a specific domain of knowledge. Fuzzy expert systems use fuzzy logic to handle uncertainties generated by imprecise, incomplete and/or vague information. The purpose of this paper is to present a comprehensive review of the methods and applications in fuzzy expert systems.

The authors have carefully reviewed 281 journal publications and 149 conference proceedings published over the past 37 years since 1982. The authors grouped the journal publications and conference proceedings separately accordingly to the methods, application domains, tools and inference systems.

The authors have synthesized the findings and proposed useful suggestions for future research directions. The authors show that the most common use of fuzzy expert systems is in the medical field.

Fuzzy logic can be used to manage uncertainty in expert systems and solve problems that cannot be solved effectively with conventional methods. In this study, the authors present a comprehensive review of the methods and applications in fuzzy expert systems which could be useful for practicing managers developing expert systems under uncertainty.

The Pediococcus strains belong to the group of lactic acid bacteria (LAB). This study aims to isolate and identify the Pediococcus spp. from mother’s milk, and investigate their tolerance to low pH and bile salts, antibacterial activity, attachment to HT-29 cells and effect on cholesterol-lowering and digestive enzymes in mice.

Pediococcus species were isolated from mother’s milk, then tested for tolerance to acid and bile salts, their antibacterial effect and attachment to HT-29 cell line. In mice experiment, the levels of triglyceride (TG), total cholesterol (TC), HDL cholesterol (HDL-C), LDL cholesterol (LDL-C) and digestive enzymes such as amylase and lipase in serum of mice were measured after administration of 10⁸ CFU/mL bacterial suspension.

A total of 24 Pediococcus spp. including 16 isolates of Pediococcus pentosaceus and 8 isolates of Pediococcus acidilactici were isolated. Fifteen isolates (62.5%) were able to survive in low pH and bile salt concentration. Ten isolates (41.6%) exhibited the most powerful inhibitory effects against both Gram-positive and Gram-negative bacterial pathogens. A total of four Pediococcus isolates (16.67%) showed strong attachment to HT-29 cells. In contrast to HDL-C and amylase, the serum levels of TC, TG and LDL-C were reduced and lipase was elevated significantly following administration of mother milk-derived Pediococcus isolates.

The Pediococcus isolates demonstrated good probiotic properties in particular cholesterol-lowering ability in mice. Thus, after more studies they can be considered as probiotic strain(s).