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Operations and maintenance management for renewable energy (RE) projects has become increasingly important in improving energy system models' precision. Specifically, some elements are uncertain and difficult to predict, such as temperature conditions or system reliability, and these result in more complicated RE projects. Suitable maintenance and insurance policies are vital to reduce risks for RE system operators. This paper formulates a profit model that integrates system reliability, predictive maintenance, and green insurance into electricity pricing and capacity problems. A non-linear optimization solution procedure is proposed to determine the optimal electricity price, capacity, investment plan, predictive maintenance budget, and insurance level while maximizing company profit. The theoretical results indicate that RE systems' increased reliability decreases the insurance level. However, an increase in the insurance level decreases RE project investments. Therefore, companies can attract more investments for RE projects if RE system reliability increases while insurance costs decrease. Additionally, this work not only presents a numerical analysis with examples and a sensitivity analysis to illustrate the model, but also discusses the opportunities this work offers for managers and analysts in practice. [ABSTRACT FROM AUTHOR]

Given the diversity of styles and sizes in apparel, marker planning which aims to arrange and move all the pattern parts of garments onto a long thin paper before the cutting process is a very important process for the apparel industry. In order to decrease the wastage of fabric after the cutting process, the marker layout essentially needs to be as compact as possible. In this paper, hybrid heuristics are proposed to conduct and achieve an optimized marker layout and length. First, a moving heuristic is presented as a new packing method to arrange and move the patterns without overlapping; here, an initial marker is presented to calculate the length. This heuristic considers multiple rotated angles and flipping positions of the patterns in order to obtain more diverse arrangements. With different arrangements, there is a higher chance of achieving an optimized marker layout and length. To further improve the solution received from the moving heuristic, soft computing algorithms are taken into account, including the genetic algorithm (GA), simulated annealing (SA), and hybrid genetic algorithm-simulated annealing (HGASA) to achieve a shorter length in the marker layout. The best marker length can be obtained from HGASA, which can save almost 28% of the length. Special cases with specific combinations in rotated angles are considered so that the industry can make informed choices on the algorithms suitable to address the marker planning problem. [ABSTRACT FROM AUTHOR]

In practice, a vendor may offer a retailer an advance-cash-credit (ACC) payment scheme. This implies the buyer needs to pay a fraction of the purchasing cost before he receives the item (advance payment), some cash when the item is arrived (cash on delivery), and then the remaining purchasing cost after a credit period (credit payment). This paper studies the effect of payment schemes on the supply chain network design. The network consists of an outside supplier, multiple distribution centers (DCs), and multiple retailers. The DCs receive an upstream ACC payment from the supplier. This study attempts to determine the optimal location, allocation, as well as the inventory cycle time while minimizing total cost. A continuous approximation is used in the model development and the time value of money concept is considered, since different payment schemes related to time change the cash value. Numerical studies are adopted to demonstrate the solution approach and the effects of changing parameters on decisions and total cost. This study provides novel management implications for supply chain network designers' reference. The results show that the number of DCs to be opened, the joint replenishment cycle time of DC, and the total cost increase as the interest earned decreases and the interest charged increases. [ABSTRACT FROM AUTHOR]