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151.
L. Gerhard 《European Journal of Lipid Science and Technology》1970,72(2):73-79
Planning of Works Involving Prevention of Corrosion in New Buildings Like all other constructional procedures the works involving prevention of corrosion must also be carefully planned within the constructional programme. This is possible if during planning, the specialist for the prevention of corrosion obtains an insight of the plan along with all the individual objects. Consequently, the specialist determines the preventive measures like derusting, coating or metallizing for each of the objects. Choice of the systems for the prevention of corrosion is dependent on the amount of stresses which the object concerned has to endure later. In his orders and contracts the customer should exactly specify the services required. 相似文献
152.
153.
Schwaighofer A Tresp V Mayer P Krause A Beuthan J Rost H Metzger G Müller GA Scheel AK 《IEEE transactions on bio-medical engineering》2003,50(3):375-382
We describe a classification system for a novel imaging method for arthritic finger joints. The basis of this system is a laser imaging technique which is sensitive to the optical characteristics of finger joint tissue. From the laser images acquired at baseline and follow-up, finger joints can automatically be classified according to whether the inflammatory status has improved or worsened. To perform the classification task, various linear and kernel-based systems were implemented and their performances were compared. Based on the results presented in this paper, we conclude that the laser-based imaging permits a reliable classification of pathological finger joints, making it a sensitive method for detecting arthritic changes. 相似文献
154.
High-pressure synthesis is a powerful method for the preparation of novel materials with high elastic moduli and hardness. Additionally, such materials may exhibit interesting thermal, optoelectronic, semiconductuing, magnetic or superconducting properties. Here, we report on the high-pressure synthesis of zirconium and hafnium nitrides with the stoichiometry M3N4, where M = Zr, Hf. Synthesis experiments were performed in a laser-heated diamond anvil cell at pressures up to 18 GPa and temperatures up to 3,000 K. We observed formation of cubic Zr3N4 and Hf3N4 (c-M3N4) with a Th3P4-structure, where M-cations are eightfold coordinated by N anions. The c-M3N4 phases are the first binary nitrides with such a high coordination number. Both compounds exhibit high bulk moduli around 250 GPa, which indicates high hardness. Moreover, the new nitrides, c-Zr3N4 and c-Hf3N4, may be the first members of a larger group of transition metal and/or lanthanide nitrides with interesting ferromagnetic or superconducting behaviour. 相似文献
155.
A fundamental objective of human–computer interaction research is to make systems more usable, more useful, and to provide users with experiences fitting their specific background knowledge and objectives. The challenge in an information-rich world is not only to make information available to people at any time, at any place, and in any form, but specifically to say the right thing at the right time in the right way. Designers of collaborative human–computer systems face the formidable task of writing software for millions of users (at design time) while making it work as if it were designed for each individual user (only known at use time). User modeling research has attempted to address these issues. In this article, I will first review the objectives, progress, and unfulfilled hopes that have occurred over the last ten years, and illustrate them with some interesting computational environments and their underlying conceptual frameworks. A special emphasis is given to high-functionality applications and the impact of user modeling to make them more usable, useful, and learnable. Finally, an assessment of the current state of the art followed by some future challenges is given. 相似文献
156.
Multi-agent Only Knowing 总被引:1,自引:0,他引:1
157.
The previously unknown linoleic acid peroxidation product 9,12-dioxo-10(Z)-decenoic acid (Z5) was detected in lentil seed fluor (Lens culinaris Medik.) by electron impact mass spectrometry (El-MS) after derivatization with pentafluorobenzyl-hydroxylamine-hydrochloride,
methylation of acidic groups with diazomethane, and protection of hydroxylic groups with N-methyl-N-trimethylsilyl-trifluoroacetamide. The structure of the natural product was confirmed by synthesis of Z5, 9,12-dioxo-10(E)-decenoic acid, and derivatives. EI-MS, nuclear magnetic resonance and gas chromatographic data of these compounds and synthetic
intermediates are discussed. 相似文献
158.
Gerhard Weck 《Datenschutz und Datensicherheit - DuD》2007,31(2):84-86
Zusammenfassung Der vom Bundesamt für Sicherheit in der Informationstechnik (BSI) entwickelte Ansatz des IT-Grundschutzes war bereits Gegenstand
von Beitr?gen in der DuD. Inzwischen hat das „Grundschutzhandbuch“ Eingang in die internationale Standard-Familie ISO 2700x
gefunden. Der Autor berichtet über die Erfahrungen mit den ersten durchgeführten Zertifizierungen nach dem neuen ISO-Standard
auf der Basis von IT-Grundschutz.
Dr. Gerhard Weck: Leiter IT Security Consulting. der INFODAS GmbH K?ln. Derzeitiger Arbeitsschwerpunkt: Entwicklung und Vermittlung
von Sicherheitskonzepten. Lizenzierter ISO 27001/IT-Grundschutz-Auditor. Autor bzw. Koautor mehrerer Bücher. Fellow der GI.
Mitglied des Pr?sidiums-Arbeitskreises „Datenschutz und IT-Sicherheit“ der GI, Sprecher der Security SIG der HP User Society
DECUS München e.V. 相似文献
159.
Ruth Breu Gerhard Popp Muhammad Alam 《International Journal on Software Tools for Technology Transfer (STTT)》2007,9(5-6):457-470
In this paper we present a novel approach for the specification of user rights in the context of an object oriented use case driven development process. Basically, we extend the specification of methods by a permission section describing the right of some actor to call the method of an object. Our approach is both role based and context based while allowing for permissions to be specified at a fine-grained data-dependent level. We use first-order logic with a built-in notion of objects and classes (provided with an algebraic semantics) as our syntactic and semantic framework. In the second part of the paper, we demonstrate the application of this approach in a model-based context to generate permissions in distributed peer-to-peer networks. 相似文献
160.
In this paper we develop an easily applicable algorithmic technique/tool for developing approximation schemes for certain types of combinatorial optimization problems. Special cases that are covered by our result show up in many places in the literature. For every such special case, a particular rounding trick has been implemented in a slightly different way, with slightly different arguments, and with slightly different worst case estimations. Usually, the rounding procedure depended on certain upper or lower bounds on the optimal objective value that have to be justified in a separate argument. Our easily applied result unifies many of these results, and sometimes it even leads to a simpler proof. 相似文献