Wafer fabrication is a capital-intensive and highly complex manufacturing process. In a wafer fabrication facility (fab), wafers are grouped as a lot to go through repeated sequences of operations to build circuitry. Lot scheduling is an important task for manufacturers in order to improve production efficiency and satisfy customers’ demands of on-time delivery. Cycle time and average work-in-process reduction while meeting customers’ requirements play an important role in improving the competitiveness and sustainability of a semiconductor manufacturer. In this research, we propose the optimal combination rules for lot scheduling problems in wafer fabs, focusing on three complex areas of decision making: lot release control, batch sizing, and dispatching lots to enhance competitiveness and sustainability of a semiconductor facility.

The objective of this study is to seek better policy options for greenhouse gas (GHG) emission reduction in Korea’s international aviation industry by analyzing economic efficiency and environmental effectiveness with a system dynamics (SD) model. Accordingly, we measured airlines sales and CO₂ emission reductions to evaluate economic efficiency and environmental effectiveness, respectively, for various policies. The results show that the average carbon emission reduction rates of four policies compared to the business-as-usual (BAU) scenario between 2015 and 2030 are 4.00% (Voluntary Agreement), 7.25% (Emission Trading System or ETS-30,000), 8.33% (Carbon Tax or CT-37,500), and 8.48% (Emission Charge System or EC-30,000). The average rate of decrease in airline sales compared to BAU for the ETS policy is 0.1% at 2030. Our results show that the ETS approach is the most efficient of all the analyzed CO₂ reduction policies in economic terms, while the EC approach is the best policy to reduce GHG emissions. This study provides a foundation for devising effective response measures pertaining to GHG reduction and supports decision making on carbon tax and carbon credit pricing.

To survive in the ceaseless cycle of competition, businesses have developed strategies to become sustainable. These strategies include reusing products, which can lead not only to the creation of economic benefits but also to improvements in a corporation’s social and environmental responsibility. Product reuse can also increase the profit earned on new products by compensating customers who bring in old products to buy new ones, as the ensuing remanufacturing process allows for the reuse of materials and thus drives down costs. As businesses have come to recognize these values, the marketing competition to retrieve used products from customers has intensified. This research focuses on identifying effective compensation strategies to determine the appropriate advertising investment and trade-in value in a market where two homogeneous retailers compete. Retailers advertise to secure more customers to trade in their used products and to generate more trade-in sales than competitors do. A retailer’s results may vary according to its competitor’s investment strategy, which makes it useful to employ information on past competitor investment patterns to plan future investment strategies. However, as competitors using one another’s information may intensify the competition, better investment results could be obtained by ignoring competitor investment information. Therefore, this study suggests four competition strategies that determine the advertisement costs and trade-in allowance spent by retailers and discusses the difference in the profits obtained by the retailers under each of the four strategies.

The Sustainability Editorial Office has been made aware that the published paper [1]

The Sustainability Editorial Office has been made aware that the published paper