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41.
Due to increasing governmental demands for tighter exhaust emission standards, a greater fuel economy, and the contrasting consumer desire for higher performance and efficiency from smaller displacement power plants, the automotive industry is turning to electronics for a wider range of applications. Electronics, specifically in the form of the microcontroller, has evolved specialized on-chip peripheral functions to meet this need. Higher resolution analog-to-digital converters, high-speed inputs and outputs, timer/counters, and watchdog timers have been added on-board to augment standard digital I/O ports, make a more cost-effective solution, and to unburden the CPU. 相似文献
42.
Central Arizona Project (CAP) is currently enhancing its water resources modeling capabilities to improve water resources management and planning activities and to better understand the inherent complexities of the Colorado River Basin system. CAP modeling activities in the Colorado River Basin extensively utilize the Colorado River Simulation System (CRSS) model. CRSS is a sophisticated object-oriented surface water model developed under the RiverWare modeling environment and maintained by the United States Bureau of Reclamation (USBR). CRSS incorporates important aspects of the Colorado River Basin: main stem, reservoirs along the river, water inflows to the river, and points of water deliveries. By using the object-oriented and rule-based capabilities of RiverWare, CRSS has embedded the rules of the Law of the River. These set of rules guide the operation and management of the Colorado River Basin’s surface water supply. This analysis executes CRSS short term simulations to evaluate the vulnerability of water deliveries to CAP from the Colorado River under different extreme hydrological and policy conditions. In the future, this type of analysis will provide key input for other CAP models, aimed to improve a quantitative understanding of the impacts of different uncertain and complex scenarios: drought conditions, future user demand behavior, reservoir operation, and optimize water recovery as a part of Arizona Water Bank Authority (AWBA), among others. 相似文献
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Elevated production of the aromatic fragrance molecule, 2‐phenylethanol,using Metschnikowia pulcherrima through both de novo and ex novo conversion in batch and continuous modes 下载免费PDF全文
Tanakorn Chantasuban Fabio Santomauro Deborah Gore‐Lloyd Sophie Parsons Daniel Henk Roderick J Scott Christopher Chuck 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2018,93(8):2118-2130
BACKGROUND
2‐phenylethanol (2PE) is a fragrance molecule predominantly used in perfumes and the food industry. It can be made from petrochemicals inexpensively, however, this is unsuitable for most food applications. Currently, the main method of production for the bio‐derived compound is to extract the trace amounts found in rose petals, which is extremely costly. Potentially fermentation could provide an inexpensive, naturally sourced, alternative.RESULTS
In this investigation, 2PE was produced from the yeast Metschnikowia pulcherrima, optimised in flasks before scaling to 2 L batch and continuous operation. 2PE can be produced in high titres under de novo process conditions with up to 1500 mg L?1 achieved in a 2 L stirred bioreactor. This is the highest reported de novo titre to date, and achieved through high sugar loadings coupled with low nitrogen conditions. The process successfully ran in continuous mode also, with a concentration of 650 mg L?1 of 2PE being maintained. The 2PE production was further increased by the ex novo conversion of phenylalanine and semi‐continuous solid phase extraction from the supernatant. Under optimal conditions 14 000 mg L?1 of 2PE was produced.CONCLUSIONS
The work presented here offers a novel route to naturally sourced 2PE through a scalable fermentation with a robust yeast highly suited to industrial biotechnology. © 2018 The Authors. Journal of Chemical Technology & Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.44.
A hybrid differential evolution and estimation of distribution algorithm based on neighbourhood search for job shop scheduling problems 总被引:1,自引:0,他引:1
Job shop scheduling problem (JSSP) is a typical NP-hard problem. In order to improve the solving efficiency for JSSP, a hybrid differential evolution and estimation of distribution algorithm based on neighbourhood search is proposed in this paper, which combines the merits of Estimation of distribution algorithm and Differential evolution (DE). Meanwhile, to strengthen the searching ability of the proposed algorithm, a chaotic strategy is introduced to update the parameters of DE. Two mutation operators are adopted. A neighbourhood search (NS) algorithm based on blocks on critical path is used to further improve the solution quality. Finally, the parametric sensitivity of the proposed algorithm has been analysed based on the Taguchi method of design of experiment. The proposed algorithm was tested through a set of typical benchmark problems of JSSP. The results demonstrated the effectiveness of the proposed algorithm for solving JSSP. 相似文献
45.
Ki-Seok Bang Jin-Young Choi Chuck Yoo 《IEEE transactions on pattern analysis and machine intelligence》2001,27(6):573-576
The paper by G.J. Holzmann (see ibid., vol.23, no.5, p.279-95, 1997) describes how to apply SPIN to the verification of a synchronization algorithm (L.M. Ruane, 1990) in process scheduling of an operating system. We report an error in the verification model presented by G.J. Holzmann and present a revised model with verification result. Our result explains the reason why SPIN found the race condition in the synchronization algorithm. We also show that the suggested fix by G.J. Holzmann is incorrect 相似文献
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Wines (Vitis vinifera L. cv. Merlot) were made by a commercial winery to examine the effects of seed removal at ∼10 °Brix on the extraction of proanthocyanidins during fermentation. Seeds were removed at the point when they fell to the bottom of the fermenter, and were thus easily removed during regular pump-over operations. Proanthocyanidin extraction was compared to wine made from traditional winemaking regime in which no seed removal occurred. Proanthocyanidin differences observed in the wines were minor. The control wine contained a slightly higher percentage molar proportion of seed proanthocyanidins ((−)-epicatechin-3-O-gallate extension and terminal subunits), demonstrating higher seed tannin extraction, and the seed removed wine contained a higher percentage molar proportion of skin proanthocyanidin indicators ((−)-epigallocatechin extension subunits). Seed removed Merlot wines had higher concentrations of total anthocyanins. Minor differences in colour measurement values between the two wines were also observed. The control wine was slightly more orange (larger hue angle, h°), lighter (larger L∗ value), and more saturated (higher chroma value, C∗) in colour. This appears to be the first paper to report the effects of early seed removal in Merlot winemaking, and demonstrates how winery tannin management techniques contribute to proanthocyanidin composition. 相似文献
48.
The traditional use of control charts necessarily assumes the independence of data. It is now recognized that many processes are autocorrelated thus violating the fundamental assumption of independence. As a result, there is a need for a broader approach to SPC when data are time-dependent or autocorrelated. This paper utilizes control charts with fixed control limits for residuals to monitor the performance of a process yielding time-dependent data subject to shifts in the mean and the autocorrelation structure. The effectiveness of the framework is evaluated by an average run length study of both X¯ and EWMA charts using analytical and simulation techniques. Average run lengths are tabulated for various process disturbance scenarios, and recommendations for the most effective monitoring tool are made. The findings of this research present motivation to extend the traditional paradigms of a shifted process (e.g., mean and/or variance). The results show that decreases in the underlying time series parameters are practically impossible to detect with standard control charts. Furthermore, the practitioner is motivated to employ runs rules since the runs are more likely with time-dependent observations. 相似文献
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