A sensor-based accelerated approach for multi-attribute machinability and tool life evaluation

This paper presents an accelerated approach and an automated system for short-term machinability evaluation of metal materials. The proposed approach is developed for ranking materials in terms of machinability. It considers both objective factors, such as machine variables and process outputs, and subjective factors, such as the decision maker's preferences regarding different criteria (objectives, e.g. operation cost, production rate, and product quality). A set of analytical and empirical formulas relevant to different aspects of machinability are identified. A definition of machinability as a function of process outputs is proposed. A method for assessing the weights of importance of different criteria is proposed. Based on the approach, a computer software package called MACPRO for machinability assessment is developed. The computerized machinability evaluation system interfacing with sensors is configured to facilitate data sampling/processing and man/machine interactions. Results of experiments with different work-piece materials for a manufacturing company and problem are analysed and discussed. The results indicate that the approach and designed system are reliable, robust, fast (about half an hour), and easy to implement. The approach is currently being implemented and used in some major metal cutting industries.     

LIFE CYCLE ASSESSMENT OF SOYBEAN OIL PRODUCTION

A life cycle assessment (LCA) case study was conducted on the processing of soybeans to soybean oil. Three stages of soybean oil processing are studied in detail: preprocessing, extraction and separation, and postprocessing. For extraction, hexane (current industrial process) and supercritical CO₂ (research and development [R & D ] laboratory‐scale process) methods are compared in detail. The initial life cycle comparison found that the laboratory‐scale CO₂ system was not as good in life cycle impacts as the hexane system. However, reasonable engineering improvements typical of scale‐up practices would make the CO₂ technology better than hexane and eliminate the hexane emissions. Utilization of membrane techniques to separate the small molecular CO₂ from the soybean oil hydrocarbon appears to be a much better R & D direction for development. This article illustrates the ability to use life cycle as an aid to R & D to select more advantageous directions for process improvement.     

MUNICIPAL RESPONSES TO HOMELESSNESS: A National Survey of “Preparedness”

ABSTRACT: This article examines the preparedness of US cities to deal with homelessness. It develops a multi-variable measure of preparedness based on the range of homelessness programs and the use of strategies for planning, acquiring necessary resources, and implementation. Research suggests that cities vary greatly in their level of preparedness, as well as with regard to the specific programs and strategies that are used. This article also examines driving forces of preparedness and finds that the federal government, along with other driving forces, significantly affects the level of municipal preparedness.     

Two-agent IDA*

The article presents an algorithm that combines Minimax's alpha-beta pruning with IDA*'s depth-first iteration and forward pruning. We prove that the algorithm, which we call Two - agent IDA* (TIDA*), is correct and is guaranteed to terminate—provided its heuristic is consistent. Minimax search has been applied with other ‘forward’ pruning or selective search techniques, but none of these techniques is guaranteed to compute the correct minimax result. We also prove that TIDA*'s accuracy monotonically increases with search depth, thus avoiding certain pathologies. Empirical results with 3×3, 4×4 and 5×5 Tic-Tac-Tff grids show that TIDA* outperforms MAB, provided both algorithms use the same consistent heuristic. However, results on a more complex search space—the 3D version of Tic-Tac-Tff—show that MAB with a good inconsistent heuristic can outperform TIDA* with a consistent heuristic even though TIDA* searches 1 to 1·5 levels deeper. This result and other empirical results suggest that an algorithm that starts with MAB and an inconsistent heuristic and then shifts near the end of the game to TIDA* with a consistent heuristic can outperform either algorithm. Finally, we present results on a forward-pruning version of MAB and show that under certain conditions it can outperform TIDA*, provided both use the same consistent heuristic.     

Volatile Constituents of Fish Protein Concentrate

SUMMARY— Progress in an investigation of the chemistry of flavor in fish protein concentrate (FPC) prepared by extraction of red hake ( Urophycis chuss ) with iso -propanol is described. Lyophilization of slurries of FPC yielded condensates from which a neutral fraction and a mixture of amine hydrochlorides were isolated. The quantity of amine mixture present was dependent on processing conditions used in the FPC preparation and was related to the flavor intensity observed. The contribution of neutral components to flavor was not determined. Based on chromatographic separations and direct investigation of components by mass spectrometry, dimethylamine, trimethylamine, ammonia, ethylamine, diethylamine, n -propyl-amine and a butylamine were identified. The probable presence of methylamine, methylethylamine and iso -propylamine was indicated.     

A Statistical Method for the Analysis of Peppermint Oils and Other Complex Mixtures

SUMMARY— A statistical method, preferably operated by a a computer, is proposed for the analysis of data on complex mixtures where the information sought involves a number of small changes in chemical composition, each of which is individually within the normal range of variation of the mixtures. When the method is applied to the identification of geographical origins of peppermint oils and mixtures of peppermint oils, the results are a substantial improvement on those from previous methods, though still leaving some uncertainty. It is expected that more complete chemical analysis will greatly improve the confidence level.