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Fixed‐bin selective assembly (FBSA) is a method for producing high‐tolerance specification assembly from lower precision components. This study investigates the design tolerance implications of an external supplier sharing dimensional information about shipped parts to be used for FBSA. An approach for reducing surplus components in FBSA is to predictively adjust the assembler's manufacturing process so that components produced internally better match those of incoming parts. However, it is unclear how the assembler's use of timely dimensions information—that is fully shared or is shared for a limited period, about the mean, variance, or both—of an externally sourced mating part would influence procedures for setting tolerances in an FBSA context. We develop and evaluate a Bayesian prediction‐based model with estimated parameters from a US assembler of bearings. Our results indicate that adjustments made using predictions from solely historical data produced comparable assembly efficiency to those made with shared information about only the dimensional variance of incoming parts. Prediction‐based adjustments, when only information about the dimensional mean was shared, yielded comparable matchable degrees to that when the mean and variance were both known. Furthermore, contrary to convention, looser tolerances were required to increase selective assembly efficiency. The shared information had a larger effect on the matchable degree than the modification of design tolerances in the absence of such information sharing. The insights have implications for coordinated component design and quality control. [ABSTRACT FROM AUTHOR]

Rising global greenhouse gas emissions and the impacts of resultant climate change necessitate development and deployment of carbon capture and conversion technologies. Amongst the myriad of bio-based conversion approaches under evaluation, a formate bio-economy has recently been proposed, wherein CO2-derived formate serves as a substrate for concurrent carbon and energy delivery to microbial systems. To date, this approach has been explored in chemolithotrophic and heterotrophic organisms via native or engineered formatotrophy. However, utilization of this concept in phototrophic organisms has yet to be reported. Herein, we have taken the first steps to establish formate utilization in Picochlorum renovo, a recently characterized eukaryotic microalga with facile genetic tools and promising applied biotechnology traits. Plastidial heterologous expression of a formate dehydrogenase (FDH) enabled P. renovo growth on formate as a carbon and energy source. Further, FDH expression enhanced cultivation capacity on ambient CO2, underscoring the potential for bypass of conventional CO2 capture and concentration limitations. This work establishes a photoformatotrophic cultivation regime that leverages light energy-driven formate utilization. The resultant photosynthetic formate platform has widespread implications for applied phototrophic cultivation systems and the bio-economy at large.

This study investigates the value of a supplier sharing information about the quality‐distribution (i.e., dimensional mean or variance) of components with an assembler who matches such parts with the selective assembly of an intermediary component. Selective assembly is a strategy that is widely used by high‐precision manufacturing companies to gain a competitive advantage in product quality. The use of inexpensive intermediary components (e.g., bearings) to ensure that all mating components are matched with acceptable clearance is a contemporary way of reducing shortage and surplus component costs associated with the traditional fixed‐bin selective assembly process. We develop and analyze a Bayesian model for information sharing in this environment, with results indicating that substantial savings occur with the use of shared information from the supplier in a fixed‐bin selective assembly of an intermediary‐component (FBSAI) context. However, there is a hierarchy regarding benefits, whereas the sharing of information which includes the process mean is most beneficial, and the sharing of only process variance information is least beneficial. The savings can assist the assembler in determining the investment required to create and maintain a profitable quality‐distribution information‐sharing network of suppliers, thus making the shared information advantageous for both the buying and selling organization. [ABSTRACT FROM AUTHOR]

This research considers quantity discount procedures under conditions of multiple items, resource limitations and multiple suppliers. This is a very complex problem that has not yet been addressed in the literature. In this paper we offer an efficient heuristic programming procedure for evaluating alternative discount schedules. Moreover we use an example problem to test the suggested procedure. The results offer several encouraging findings for managers facing this impressive problem. [ABSTRACT FROM AUTHOR]

The paper reports the results of several simulation experiments that compare alternative procedures for determining purchase quantities in MRP systems when multiple discounts are available. The procedures are the modified least unit cost (LUCm), the modified McLaren's order moment (MOMm) and a traditional procedure (DOQ) that is commonly used when evaluating quantity discounts. For this work, three purchased parts with two levels of discount attractiveness. two price break offerings, requirement lumpiness and requirement uncertainty were used to test 810 observations. This research indicates that the LUCm and MOMm procedures out perform the traditional procedure when multiple discounts are available. In the addition, for high discount attractiveness between the prices breaks, the LUCm and MOMm procedures are more than five per cent better than the traditional procedure. When the discount attractiveness between the price breaks is low, there is very little difference in the performance of the alternative procedures. Moreover the LUCm procedure requires 13.45 per cent fewer units of inventory than the MOMm procedure and 66.35 per cent units than the traditional procedure. LUCm emerges as the procedure of choice for the multiple discount lot-sizing problem in material requirements planning (MRP) systems. The LUCm procedure is easily understood: it takes advantage of multiple discounts; it uses considerably less safety stock and places fewer orders. [ABSTRACT FROM AUTHOR]

3-Hydroxybutyrate (3HB) is a product of interest as it is a precursor to the commercially produced bioplastic polyhydroxybutyrate. It can also serve as a platform for fine chemicals, medicines, and biofuels, making it a value-added product and feedstock. Acetogens non-photosynthetically fix CO2 into acetyl-CoA and have been previously engineered to convert acetyl-CoA into 3HB. However, as acetogen metabolism is poorly understood, those engineering efforts have had varying levels of success. 3HB, using acetyl-CoA as a precursor, can be synthesized by a variety of different pathways. Here we systematically compare various pathways to produce 3HB in acetogens and discover a native (S)-3-hydroxybutyryl-CoA dehydrogenase, hbd2, responsible for endogenous 3HB production. In conjunction with the heterologous thiolase atoB and CoA transferase ctfAB, hbd2 overexpression improves yields of 3HB on both sugar and syngas (CO/H2/CO2), outperforming the other tested pathways. These results uncovered a previously unknown 3HB production pathway, inform data from prior metabolic engineering efforts, and have implications for future physiological and biotechnological anaerobic research.