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1.
Combining multiple knowledge bases 总被引:2,自引:0,他引:2
Combining knowledge present in multiple knowledge base systems into a single knowledge base is discussed. A knowledge based system can be considered an extension of a deductive database in that it permits function symbols as part of the theory. Alternative knowledge bases that deal with the same subject matter are considered. The authors define the concept of combining knowledge present in a set of knowledge bases and present algorithms to maximally combine them so that the combination is consistent with respect to the integrity constraints associated with the knowledge bases. For this, the authors define the concept of maximality and prove that the algorithms presented combine the knowledge bases to generate a maximal theory. The authors also discuss the relationships between combining multiple knowledge bases and the view update problem 相似文献
2.
Pilot simplex experiments for improving the tablet strength of three aspirin tablet formulations based on precompression and compression forces were presented. As each simplex moved towards the direction of the optimum, the friability was being minimized and the crushing strength was concomittantly being maximized. Because it followed a systematic direction, simplex process would locate a local optimum rapidly. The appropriate levels of precompression and compression forces that produced tablets with the desired strength were attained in five trials. By contrast, random search for this force combination required at least ten trials. Simplex technique is a cost and time effective means for determining the precompression and compression forces that will reduce the friability or increase the hardness of a tablet formulation. Results appeared to also indicate that crushing strength might be a more reliable measure of tablet strength than friability. 相似文献
3.
4.
Beliefs, time and incomplete information in multiple encounter negotiations among autonomous agents 总被引:1,自引:0,他引:1
Sarit Kraus 《Annals of Mathematics and Artificial Intelligence》1997,20(1-4):111-159
In negotiations among autonomous agents over resource allocation, beliefs about opponents, and about opponents’ beliefs, become
particularly important when there is incomplete information. This paper considers interactions among self‐motivated, rational,
and autonomous agents, each with its own utility function, and each seeking to maximize its expected utility. The paper expands
upon previous work and focuses on incomplete information and multiple encounters among the agents. It presents a strategic
model that takes into consideration the passage of time during the negotiation and also includes belief systems. The paper
provides strategies for a wide range of situations. The framework satisfies the following criteria: symmetrical distribution,
simplicity, instantaneously, efficiency and stability.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
5.
6.
Gaidis M.C. Friedrich S. Segall K. Prober D.E. Szymkowiak A.E. Moseley S.H. 《Applied Superconductivity, IEEE Transactions on》1996,6(1):1-4
We report the development of Nb-Ta-Al-Al2O3-Al superconducting tunnel junction structures for high energy resolution and high efficiency X-ray detection. These devices utilize a Ta X-ray absorber with superconductor “bandgap engineered” quasiparticle trapping to improve charge collection. Experimental results at 0.3 K are presented, showing energy resolution of 102 eV full-width-half-maximum for 6 keV X-rays. Collected charge is in excess of 5×106 electrons. The absorption efficiency is better than 35%. Devices thermally cycle with no change in characteristics 相似文献
7.
Norbert Fischer Siegfried Nitz und Friedrich Drawert 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1987,185(3):195-201
Zusammenfassung In grünem (Taiwan Gunpowder) und schwarzem (Ceylon high OP) Tee sind beträchtliche Mengen an Aromastoffen in glykosidischer Bindung vorhanden; ihr Anteil ist sogar höher als der an freien Aromastoffen. Hauptkomponenten sind in beiden Teesorten cis-3-Hexen-1-ol, Benzylalkohol und 2-Phenylethanol in gebundener Form, dazu im Schwarztee Linalool und im grünen Tee Geraniol. Die unterschiedlichen Anteile dieser beiden Terpenalkohole spiegeln die unterschiedlichen Tee-Varietäten wieder, denen die untersuchten Teesorten angehören: der Ceylon-Tee ist der Varietätassamica zuzuordnen, der Tee aus Taiwan der Varietätsinensis. Die Zusammensetzung der aus gebundenen Formen freisetzbaren Aromastoffe war ähnlich komplex wie die der freien Aromastoffe, wobei die Unterschiede zwischen den beiden Teesorten auf den verschiedenen Herstellungsverfahren beruhen. Das Auftreten gebundener Formen solcher Aromastoffe, die nicht originär vorhanden sind, sondern erst während der Welk- oder der Fermentationsphase gebildet werden, impliziert das Vorhandensein glykosidierender Aktivitäten im Teeblatt noch in relativ späten Stadien der Schwarzteeherstellung. Die Untersuchung der gebundenen Anteile an Aromastoffen trägt neben der Analyse der freien Aromastoffe wesentlich zum Verständnis der Reaktionen im Teeblatt wahrend der verschiedenen Produktionsstadien bei.
Auszug aus der Dissertation von N. Fischer, Technische Universitat München 1986
1. Mitteilung Chem Mikrobiol Technol Lebensm 9:87 (1985) 相似文献
Bound flavour compounds in plants 2. Part. Free and bound flavour compounds in green and black tea
Summary Green and black tea contains considerable amounts of flavour compounds which are present in glycosidic bonds, their portion being even higher than that of free flavour compounds. The main components in both of these tea varieties are 3-hexene-1-ol, benzylalcohol and 2-phenylethanol, which are present in the bound forms, and additionally linalool in black tea and geraniol in green tea. The different amounts of these terpene alcohols reflect the different varieties the teas under investigation belong to: the Ceylon tea belongs to the variety assamica, and the Taiwan tea to the variety sinensis. The composition of the flavour compounds liberated from bound forms had a similar complexity to that of the free flavour compounds, the difference being based upon the different production procedures. The occurrence of bound forms of such components that are not originally present but are produced during the withering or fermentation stage implies that glycosidating activities are still present in the tea leaf, even in a relatively late stage of the black tea production process. The investigation of the bound parts of flavour compounds delivers a valuable contribution to a better understanding of the reactions occurring in the tea leaf during the different stages of tea production.
Auszug aus der Dissertation von N. Fischer, Technische Universitat München 1986
1. Mitteilung Chem Mikrobiol Technol Lebensm 9:87 (1985) 相似文献
8.
Manfred Edelhäuser und Karl-Gustav Bergner 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1987,184(3):189-194
Zusammenfassung Die Isolierung der Saccharase (E.C. 3.2.1.20) aus den Proteinkonzentraten von Raps-, Tannen- und Zuckerfütterungshonig wird beschrieben. Die Abtrennung von anderen Enzymen, insbesondere von saurer Phosphatase gelingt durch hydrophobe Wechselwirkungschromatographie, von inerten Proteinen durch Gelfiltration. Im Zusammenhang damit wird das Verhalten des Enzyms bei der Chromatographie an Anionenaustauschern, an Hydroxylapatit und an immobilisiertem Weizenkeimlectin untersucht. Dabei ergab sich am Lectin-Gel eine Trennung in zwei multiple Formen.Die Saccharase aus allen drei Honigsorten verhielt sich einheitlich, woraus zu schließen ist, daß sie ausschließlich von der Biene stammt. Ihre Molekül masse wurde gelchromatographisch zu 57000 ermittelt.
The proteins of honeyVIII. Honey sucrase, isolation, chromatographic behaviour and properties
Summary The isolation of the honey sucrase (E.C. 3.2.1.20) from rape- and fir-honey as well as from honey obtained after sugar feeding is described. The separation from other honey enzymes especially from acid phosphatase succeded by reversed phase chromatography. Separation of other, non-active proteins was accomplished by gel permeation chromatography. The behaviour of the honey sucrase upon chromatography on anion exchangers, on hydroxylapatite and wheat germ lectin was investigated. No differences were found between the sucrases of the three honeys.The molecular weight was determined at 57 000. By affinity chromatography with wheat germ lectin the enzyme could be separated into two multiple forms.相似文献
9.
Tryptic, thermitatic, and tryptic-thermitatic Faba bean protein hydrolyzates as well as their equimolar mixture of amino acids were perfused through proximal and distal parts of the intestine (10 cm length) of non-narcotized rats. The total amino-acid concentration of the perfused solution was 50 mM. The absorption of nitrogen and total amino acids from the tryptic and tryptic-thermitatic hydrolyzates was lower than that from the amino-acid mixture, the absorption from the thermitatic hydrolyzate was in accordance with that from the amino-acid mixture. The absorption pattern of the amino acids which preferably undergo a peptidic absorption is similar with the three hydrolyzates: in the proximal intestinal part this concerns glutamic acid and serine, in the distal intestinal part--methionine, alanine, glycin, and serine. The absorption pattern of the amino acids is different between the three hydrolyzates and the amino-acid mixture. Between the absorption pattern of the amino acids from the three hydrolyzates little differences were evident only in the proximal intestinal part. The coefficients of variation of the tryptic-thermitatic hydrolyzates are in accordance with those of the amino-acid mixture, whereas that of the thermitatic hydrolyzates is significantly lower. In the distal intestinal part all supplied forms are more rapidly absorbed than in the proximal part of the intestine. 相似文献
10.
Th. Hilbert und P. B?ttcher 《Holz als Roh- und Werkstoff》1985,43(6):242
Ohne Zusammenfassung 相似文献