Specification of Process Design Variables for Complex Evaporation Plants

A general expression is developed for determining the degree of freedom in the design of a multiple-effect evaporation plant having some or all of the following auxiliary features: condensate flash tanks, liquor flash tanks, intermediate liquor heaters, multiple feeds, finisher unit, vapor bleed points, and twin-body evaporator effects. These degrees of freedom are utilized in specifying the process design variables for the evaporation plant.     

A polynomial-time algorithm for optimal clustering in a special class of {0, l} -matrices

The process of forming group technology based families for cellular manufacturing applications often entails the identification ofclusters in {0, l}-matrices. Most of the methods developed to date for cluster formation in this context employ heuristics that typically generate sub-optimal solutions (in terms of the number of exceptional elements). In this paper, we will describe a polynomial-time algorithm, based on a graph-theoretic approach, for optimal cluster formation in a class of {0, l}-matrices called vertex-tree graphic matrices. A comparison of the performance of this algorithm with popular heuristics is also provided. The algorithm can be used as a benchmarking tool for cluster formation heuristics.     

Robust approaches to quantitative ratiometric FRET imaging of CFP/YFP fluorophores under confocal microscopy

Ratiometric quantification of CFP/YFP FRET enables live-cell time-series detection of molecular interactions, without the need for acceptor photobleaching or specialized equipment for determining fluorescence lifetime. Although popular in widefield applications, its implementation on a confocal microscope, which would enable sub-cellular resolution, has met with limited success. Here, we characterize sources of optical variability (unique to the confocal context) that diminish the accuracy and reproducibility of ratiometric FRET determination and devise practical remedies. Remarkably, we find that the most popular configuration, which pairs an oil objective with a small pinhole aperture, results in intractable variability that could not be adequately corrected through any calibration procedure. By quantitatively comparing several imaging configurations and calibration procedures, we find that significant improvements can be achieved by combining a water objective and increased pinhole aperture with a uniform-dye calibration procedure. The combination of these methods permitted remarkably consistent quantification of sub-cellular FRET in live cells. Notably, this methodology can be readily implemented on a standard confocal instrument, and the dye calibration procedure yields a time savings over traditional live-cell calibration methods. In all, identification of key technical challenges and practical compensating solutions promise robust sub-cellular ratiometric FRET imaging under confocal microscopy.     

Methodologies for rapid and effective response to requests for quotation (RFQs)

The ability to respond quickly and effectively to requests for quotation (RFQs) from customers can be a significant source of competitive advantage to manufacturing companies. This paper presents a new paradigm for processing RFQs and describes methodologies for rapid and accurate estimation of manufacturing cost for modified standard products and custom-made products. Insights gained through industry collaboration on the development of rapid cost estimation systems are also discussed. The work presented in this paper complements ongoing efforts by government and industry to establish the infrastructure and enabling technologies for electronic commerce, and can therefore contribute to significant gains in supply chain agility.