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991.
This paper presents an automatic construction of Korean WordNet from pre-existing lexical resources. We develop a set of automatic word sense disambiguation techniques to link a Korean word sense collected from a bilingual machine-readable dictionary to a single corresponding English WordNet synset. We show how individual links provided by each word sense disambiguation method can be non-linearly combined to produce a Korean WordNet from existing English WordNet for nouns. 相似文献
992.
993.
This paper investigates the use of disturbance models in the design of wind turbine individual pitch controllers. Previous work has used individual pitch control and disturbance models with the Multiblade Coordinate Transformation to design controllers that reduce the blade loads at the frequencies associated with the rotor speed. This paper takes a similar approach of using a disturbance model within the H∞ design framework to account for periodic loading effects. The controller is compared with a baseline design that does not include the periodic disturbance model. In constant wind speeds, the disturbance model design is significantly better than the baseline design at canceling blade loads at the rotor frequencies. However, these load reduction improvements become negligible even under low turbulent wind conditions. The two controllers perform similarly in turbulent wind conditions because disturbance augmentation improves load reduction only at the multiples of the rotor frequency in the yaw and tilt moment channels whereas turbulence creates strong collective bending moments. In addition, turbulent wind contains energy across a broad frequency spectrum and improvements at multiples of the rotor frequency are less important in these conditions. Therefore inclusion of periodic disturbance models in the control design may not lead to the expected load reduction in fielded wind turbines. 相似文献
994.
Ilgu Yun Lawrence A. Carastro Ravi Poddar Martin A. Brooke Gary S. May Kyung‐Sook Hyun Kwang Eui Pyun 《ETRI Journal》2000,22(1):38-46
The extraction of model parameters for embedded passive components is crucial for designing and characterizing the performance of multichip module (MCM) substrates. In this paper, a method for optimizing the extraction of these parameters using genetic algorithms is presented. The results of this method are compared with optimization using the Levenberg‐Marquardt (LM) algorithm used in the HSPICE circuit modeling tool. A set of integrated resistor structures are fabricated, and their scattering parameters are measured for a range of frequencies from 45 MHz to 5 GHz. Optimal equivalent circuit models for these structures are derived from the s‐parameter measurements using each algorithm. Predicted s‐parameters for the optimized equivalent circuit are then obtained from HSPICE. The difference between the measured and predicted s‐parameters in the frequency range of interest is used as a measure of the accuracy of the two optimization algorithms. It is determined that the LM method is extremely dependent upon the initial starting point of the parameter search and is thus prone to become trapped in local minima. This drawback is alleviated and the accuracy of the parameter values obtained is improved using genetic algorithms. 相似文献
995.
996.
Josphine Charve Chi Chen Adrian D Hegeman Gary A Reineccius 《Flavour and Fragrance Journal》2011,26(6):429-440
This work was conducted as the initial part of the evaluation of flavoromics as a tool in flavour research. The objective was to develop and evaluate methods for the untargeted analysis of chemical stimuli of orange juice flavour. It considered for study all (ideally) low molecular weight compounds as candidate chemical stimuli in flavour perception (unbiased) instead of focusing only on compounds already known to influence the flavour quality. Four commercial juices and their blend were analysed by headspace solid‐phase micro‐extraction gas chromatography (GC) and ultra‐high‐performance liquid chromatography (UHPLC)–time of flight mass spectrometry for volatiles and non‐volatiles, respectively. The developed methods were a compromise between the number of compounds extracted and detected, throughput and repeatability. The methods were tested for their ability to distinguish between orange juices based on mass spectral information using chemometrics. Classification of the samples was not the goal of the study but rather an indirect way to test the instrumental methods, the handling and chemometric analysis of these data. Classification models were obtained which allowed the categorization of the samples by brands with little overlapping, and the tight clustering of the replicates indicated a good repeatability of the methods, especially for GC and RP‐UHPLC. Fusion of GC‐ and RP‐UHPLC‐MS data sets gave similar classification models compared to that of using only data from volatiles or non‐volatiles but can offer the advantage of finding potential correlations between chemical compounds and increased accuracy in flavour predictions as it includes inputs from more compounds. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
997.
Yoon Y Geornaras I Scanga JA Belk KE Smith GC Kendall PA Sofos JN 《Journal of food science》2011,76(6):M450-M455
Abstract: This study developed growth/no growth models for predicting growth boundaries of Listeria monocytogenes on ready‐to‐eat cured ham and uncured turkey breast slices as a function of lactic acid concentration (0% to 4%), dipping time (0 to 4 min), and storage temperature (4 to 10 °C). A 10‐strain composite of L. monocytogenes was inoculated (2 to 3 log CFU/cm2) on slices, followed by dipping into lactic acid and storage in vacuum packages for up to 30 d. Total bacterial (tryptic soy agar plus 0.6% yeast extract) and L. monocytogenes (PALCAM agar) populations were determined on day 0 and at the endpoint of storage. The combinations of parameters that allowed increases in cell counts of L. monocytogenes of at least l log CFU/cm2 were assigned the value of 1, while those limiting growth to <1 log CFU/cm2 were given the value of 0. The binary data were used in logistic regression analysis for development of models to predict boundaries between growth and no growth of the pathogen at desired probabilities. Indices of model performance and validation with limited available data indicated that the models developed had acceptable goodness of fit. Thus, the described procedures using bacterial growth data from studies with food products may be appropriate in developing growth/no growth models to predict growth and to select lactic acid concentrations and dipping times for control of L. monocytogenes. Practical Application: The models developed in this study may be useful in selecting lactic acid concentrations and dipping times to control growth of Listeria monocytogenes on cured ham and uncured turkey breast during product storage, and in determining probabilities of growth under selected conditions. The modeling procedures followed may also be used for application in model development for other products, conditions, or pathogens. 相似文献
998.
BACKGROUND: Escherichia coli O157:H7 can survive commercial manufacture of some uncooked fermented meats. External application of microencapsulated allyl isothiocyanate (AIT) or hot (non‐deheated) yellow mustard powder was used to inactivate the pathogen during dry‐cured Westphalian ham manufacture. RESULTS: Within 45/80 days, E. coli O157:H7 numbers were reduced 5 log10 CFU g?1 by 400 µg kg?1 AIT or 60 g kg?1 mustard powder, but 80 days were required in the untreated control. Mustard powder but not AIT reduced numbers of lactic acid bacteria and staphylococci. Mustard powder or ≥ 300 µg kg?1 AIT inhibited yeasts and moulds but did not affect ham pH or water activity. CONCLUSION: The commercial Westphalian ham process without AIT or mustard powder treatment was validated capable of reducing E. coli O157:H7 5 log10 CFU g?1. Surface treatments with ≥ 300 µg kg?1 microencapsulated AIT or 60 g kg?1 yellow mustard powder reduced the time required for this reduction by 40–50%. AIT volatility from microcapsules or hot mustard powder during application of these compounds may restrict their use in production facilities. Copyright © 2009 Society of Chemical Industry 相似文献
999.
Lee D. Green Jeff Smith Gary Bryant Rachel Cooper Kyung‐won Chung Maryann Finiw 《Design Management Review》2004,15(2):74-79
Design management integrates two very different realities. To probe the background needed to embrace this duality, we invited six experts from the corporate, consultant, and academic worlds—Lee Green, Jeff Smith, Gary Bryant, Rachel Cooper, Kyung‐won Chung, and Maryann Finiw—to comment on the business knowledge and attitudes that distinguish designers from design managers. 相似文献
1000.
Andrew Hyland Hamed Rezaishiraz Joseph Bauer Gary A Giovino K Michael Cummings 《Nicotine & tobacco research》2005,7(3):461-468
Average daily cigarette consumption has decreased, and some evidence suggests that the rate of \"some day\" smoking has increased; however, relatively little is known about low-level smokers. The present analysis describes and compares low-level versus heavier smokers, using cross-sectional and longitudinal data. Data from the Community Intervention Trial for Smoking Cessation (COMMIT) were used in this analysis. Population-based cross-sectional tobacco use telephone surveys were performed in 22 North American communities in 1988 and 1993, and the prevalence and characteristics of low-level smoking and reasons for quitting are reported from the 1993 prevalence survey. In addition, a cohort of 6,603 smokers was identified in 1988 and interviewed again in 1993 and 2001 to assess patterns of low-level smoking over time and its association with smoking cessation. In 1988, 7.6% were low-level smokers; in 1993, 10.7% were low-level smokers. Compared with heavier smokers, low-level smokers were more likely to be female, older, not married, Black or Hispanic; to have a 4-year college degree; to have no other adult smokers in the household; and to wait longer in the day to have their first cigarette. Low-level smokers also were less likely to report trying to quit because of the expense of smoking or physician advice to quit. They were more likely to try to quit because of trying to set a good example; concern for second-hand smoke; and factors such as bad breath, smell, or the taste of smoking. Those who smoked full-priced premium brands and who worked in a completely smoke-free worksite were more likely to be low-level smokers. Compared with heavier smokers, low-level smokers had similar rates of making a future quit attempt, lower use rates of nicotine replacement therapy, and higher cessation rates. Low-level smokers may be a growing segment of the smoker population and have different characteristics, health risks, and intervention needs compared with their heavier smoking counterparts. 相似文献