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101.
The kinetics of cyclotrimerization and the thermal stability of bisphenol Abased cyanate ester resin systems were determined using Fourier transform infrared spectroscopy, differential scanning calorimetry, and thermogravimetry. The bisphenol A dicyanate was cured with 4 phr nonylphenol and with the octoates of zinc and manganese, and cobalt acetylacetonate at concentrations ranging from 0 to 750 ppm metal. An empirical rate law was used to predict the cyanate concentration profiles. The observed reaction rate showed a first-order dependen?e on the initial metal concentration and a second-order dependence on the cyanate concentration in the kinetically controlled regime. For the uncatalyzed systems, the kinetics was described by a second-order autocatalytic model. The thermal stability of the network was found to be dependent on the catalyst concentration for the zinc catalysts. For the samples cured with manganese, no effect of concentration on the thermal stability was observed. 相似文献
102.
The typical inventory routing problem deals with the repeated distribution of a single product from a single facility with an unlimited supply to a set of customers that can all be reached with out-and-back trips. Unfortunately, this is not always the reality. We introduce the inventory routing problem with continuous moves to study two important real-life complexities: limited product availabilities at facilities and customers that cannot be served using out-and-back tours. We need to design delivery tours spanning several days, covering huge geographic areas, and involving product pickups at different facilities. We develop an innovative randomized greedy algorithm, which includes linear programming based postprocessing technology, and we demonstrate its effectiveness in an extensive computational study. 相似文献
103.
Potential applications of knowledge based expert systems in the area of construction project monitoring and control are described. Originally developed from research in artificial intelligence, these systems are computer programs that can undertake intelligent tasks currently performed by highly skilled people. While some project monitoring can be accomplished by algorithmic procedures, the capability of knowledge based expert systems to deal with illstructured problems and to be extensively modified over time make them desirable for application in this area. Sample applications and heuristic rules in scheduling and inventory control are provided. 相似文献
104.
Dr. Martin Meints 《Datenschutz und Datensicherheit - DuD》2006,30(1):13-16
Datenschutzmanagement ist eine gesetzlich verankerte Aufgabe, muss sich aber unter Wirtschaftlichkeitsgesichtspunkten in der betrieblichen und zunehmend auch der behördlichen Praxis in andere, bereits etablierte Prozessmanagementstrukturen wie ITIL oder Informationssicherheits-management Systeme (ISMS) einordnen. In diesem Beitrag werden die Möglichkeiten untersucht, die IT-Grundschutz als ein zukünftiges, ISO 27001-kompatibles ISMS bietet. Unter dem Gesichtspunkt der Normierung scheint eine Aktualisierung des Bausteins 3.5 “Datenschutz” dringend. 相似文献
105.
Publications on optimal control of irreversible thermodynamic processes are reviewed. Analogies between irreversible processes in thermodynamics and microeconomics are stated. 相似文献
106.
Vallerand Robert J.; Blais Marc R.; Lacouture Yves; Deci Edward L. 《Canadian Metallurgical Quarterly》1987,19(1):1
Conducted a reliability and validity study of the French version of E. L. Deci and R. M. Ryan's (1985) General Causality Orientations Scale (GCOS), which measures the extent to which people are oriented toward the autonomy, control, and impersonal aspects of the initiation and regulation of behavior. Findings support the psychometric and construct validity of the French version of the GCOS; suggestions for its use in French-Canadian psychological research are discussed. (English abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
107.
108.
Surendra P. Verma Jean R. Philippot Bernard Bonnet Josette Sainte-Marie Yves Moschetto Donald F. H. Wallach 《Lipids》1985,20(12):890-896
Raman and resonance Raman spectra of plasma lipoproteins ± malondialdehyde were studied at concentrations which block the
normal receptor-mediated uptake by cells. The strong resonance Raman bands at about 1010, 1162 and 1530 cm−1, due to the presence of carotenoids in the lipoproteins, are envisaged as structural probes. High resolution resonance Raman
spectra of the 1500–1600 cm−1 region reveal multiple features suggesting the coexistence of several structural populations of β-carotene whose precise
assignment is complex. When plasma lipoproteins are reacted with malondialdehyde, a complex change occurs in the resonance
Raman banding of β-carotene in the 1500–1600 cm−1 region. Malonaldehyde (MDA) also modifies the acoustical region (70–200 cm−1 of low density lipoprotein (LDL) lipids. We suggest that malondialdehyde association with plasma lipoproteins alters the
lipid structure via apoprotein or apoprotein/lipid associations. 相似文献
109.
Outage in digital microwave radio systems during multipath fading is highly correlated with the channel amplitude dispersion. This characteristic is exploited in a new digital microwave radio system measurement technique which yields dispersion signatures. These dispersion signatures can be readily applied to assess the effects of time varying channels on digital radio equipment. Thus, dispersion signatures can be used for in-service monitoring of equipment operation during actual fading. Routine maintenance assessment and laboratory evaluation of digital microwave radio equipment can also be readily carried out. The laboratory evaluation results can be used for system design both with and without diversity. 相似文献
110.
XML hat sich als Sprache zur Definition von Dokumenten für den universellen Datenaustausch etabliert. XML-Schema erm?glicht
ausgefeilte Definitionen für XML-Dokumente und hat beste Chancen, die bisher eingesetzte DTD abzul?sen. Neben einer allgemeinen
Einführung geht dieser Beitrag auch auf verfügbare Produkte und neue M?glichkeiten der objektorientierten Softwareentwicklung
mit XML-Schema ein.
Vorschl?ge an Prof. Dr. Frank Puppe <puppe@informatik.uni-wuerzburg.de> oder Dieter Steinbauer <dieter.steinbauer@schufa.de>
Alle „Aktuellen Schlagw?rter” seit 1988 finden Sie unter: www.ai-wuerzburg.de/as 相似文献