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61.
62.
Zusammenfassung. Aus finanzwirtschaftlicher Sicht k?nnen Kreditgarantien als Verkaufsoptionen auf das anteilige Gesamtverm?gen einer Unternehmung
interpretiert werden. Die Bewertung von Kreditgarantien erfolgt üblicherweise mit dem Ansatz von Merton. Bei diesem Modell
wird jedoch unterstellt, da? sowohl für den garantierten Kredit als auch für das nicht garantierte Fremdkapital vor Ablauf
der Laufzeit keinerlei Zins– und Tilgungszahlungen geleistet werden. Unsere Arbeit pr?sentiert ein Modell zur Bewertung von
Garantien auf Kredite mit beliebigen Zins– und Tilgungsmodalit?ten. Das vorgeschlagene Bewertungsmodell wird auf Kredite mit
unterschiedlichen Tilgungsformen angewendet. Darüber hinaus werden Sensitivit?tsanalysen bezüglich der Einflu?faktoren auf
die aus dem Modell resultierenden Pr?miens?tze durchgeführt.
Eingegangen: 2. Februar 1999 / Angenommen: 9. Dezember 1999 相似文献
63.
The pyrolytic conversion of bis-Lewis base adducts of decaborane(14), L·B10H12·L (L=neutral monophosphine) and phosphonium salts of the [B10H10]2– anion (e.g. [Ph4P+]2, etc.), to ceramic materials has been studied. All species examined served as binders for a variety of non-oxide refractory ceramic powders (e.g. B4C, BN, BP, B13P2, SiC, Si3N4, B, C, AIN). 相似文献
64.
Temperature‐dependent coefficient of thermal expansion (CTE) of injection molded,short‐glass‐fiber‐reinforced polymers
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A deep understanding of the anisotropic, composite‐, geometry‐, and temperature‐dependent coefficient of thermal expansion (CTE) of short‐fiber‐reinforced polymers is often needed in material development and at early stages of the design process of injection molded parts. Usually, the data available does not reflect the complex behavior and the knowledge about the influences and interactions are missing. This paper deals with a method for calculating the composite‐, geometry‐, and temperature‐dependent anisotropic CTE of parts made from short‐fiber reinforced polymers without respectively low preload to create an understanding of its origins and influential factors. Here, a good accordance between the measurements and calculations was achieved. POLYM. ENG. SCI., 55:2661–2668, 2015. © 2015 Society of Plastics Engineers 相似文献
65.
Catalysis of an Essential Step in Vitamin B2 Biosynthesis by a Consortium of Broad Spectrum Hydrolases
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Sonja Sarge Dr. Ilka Haase Dr. Boris Illarionov Dr. Dietmar Laudert Dr. Hans‐Peter Hohmann Prof. Adelbert Bacher Prof. Markus Fischer 《Chembiochem : a European journal of chemical biology》2015,16(17):2466-2469
An enzyme catalysing the essential dephosphorylation of the riboflavin precursor, 5‐amino‐6‐ribitylamino‐2,4(1H,3H)‐pyrimidinedione 5′‐phosphate ( 6 ), was purified about 800‐fold from a riboflavin‐producing Bacillus subtilis strain, and was assigned as the translation product of the ycsE gene by mass spectrometry. YcsE is a member of the large haloacid dehalogenase (HAD) superfamily. The recombinant protein was expressed in Escherichia coli. It catalyses the hydrolysis of 6 (vmax, 12 μmol mg?1 min?1; KM, 54 μm ) and of FMN (vmax, 25 μmol mg?1 min?1; KM, 135 μm ). A ycsE deletion mutant of B. subtilis was not riboflavin dependent. Two additional proteins (YwtE, YitU) that catalyse the hydrolysis of 6 at appreciable rates were identified by screening 13 putative HAD superfamily members from B. subtilis. The evolutionary processes that have resulted in the handling of an essential step in the biosynthesis of an essential cofactor by a consortium of promiscuous enzymes require further analysis. 相似文献
66.
Gtz Hüsken Stephan Pirskawetz Dietmar Meinel Veronika Babski Hans‐Carsten Kühne 《Bautechnik》2016,93(10):711-716
Methods for analyzing the fracture behavior of high‐strength steel fiber‐reinforced concretes High‐strength and ultra‐high strength fiber‐reinforced concretes are most suitable for applications with extreme mechanical loads. These extreme conditions require a ductile behavior under tensile loading, which is obtained solely by the addition of steel fibers and their working mechanism. Profound know ledge on the working mechanism of the steel fibers is necessary for optimizing this material. Usually, this knowledge is obtained by means of classical measuring techniques of destructive tests. Adopting measuring techniques from non‐destructive material testing helps to analyze and to identify the different stages of the fracture mechanism of high‐strength and ultra‐high strength fiber‐reinforced concretes in detail. The application of different non‐destructive measuring techniques is shown exemplary on tensile tests conducted on an ultra‐high strength fiber‐reinforced concrete and its applicability for analyzing the fracture behavior is discussed. The main focus is on the characterization of the relevant failure modes under tensile loading by the different measuring techniques and the comparison with classical measuring techniques (e. g. extensometer). The tensile tests have been analyzed by optical deformation measurements using digital image correlation (DIC), acoustic emission analysis (AE), and 3D computed tomography (CT). 相似文献
67.
Frank Herzel Sabbir A. Osmany Kai Hu Klaus Schmalz Ulrich Jagdhold J. Christoph Scheytt Oliver Schrape Wolfgang Winkler Rüdiger Follmann Dietmar Köther Thorsten Kohl Olaf Kersten Thomas Podrebersek Heinz-Volker Heyer Frank Winkler 《Analog Integrated Circuits and Signal Processing》2010,65(1):21-32
We present an integrated fractional-N low-noise frequency synthesizer for satellite applications. By using two integrated VCOs and combining digital and analog tuning techniques, a PLL lock range from 8 to 12 GHz is achieved. Due to a small VCO fine tuning gain and optimized charge pump output biasing, the phase noise is low and almost constant over the tuning range. All 16 sub-bands show a tuning range above 900 MHz each, allowing temperature compensation without sub-band switching. This makes the synthesizer robust against variations of the device parameters with process, supply voltage, temperature and aging. The measured phase noise is ?87 dBc/Hz and ?106 dBc/Hz at 10 kHz and 1 MHz offset, respectively. In integer-N mode, phase noise values down to ?98 dBc/Hz at 10 kHz and ?111 dBc/Hz at 1 MHz offset, respectively, were measured. 相似文献
68.
Nashwa Abo Elneel Erkan Aksoy Dietmar Schroeder 《Analog Integrated Circuits and Signal Processing》2010,64(3):249-259
A novel adaptable analog/digital converter (ADC) that combines analog/digital conversion and entropy-coding for integrated
data compression and low-power operation is reported. The converter has high flexibility of operation in terms of adaptable
resolution, conversion rate and input signal statistics. This feature allows to adaptively react to changes of the situation
and to put the device in each case into the optimum configuration. The ADC has been realized in a 0.6 μm CMOS technology with
a peak resolution of 12 bit and 200 kS/s maximum sampling rate. A comprehensive power model of the converter is presented
that reflects precisely the power consumption determined from experiments. The model is very useful for optimizing the converter
configuration in the node of a wireless sensor network for specific situations. A feasible real-life application is demonstrated. 相似文献
69.
70.
Suelen Barg Elisângela Guzi de Moraes Dietmar Koch Georg Grathwohl 《Journal of the European Ceramic Society》2009,29(12):2439-2446
Open porous mechanically stable ceramic foams are developed by a simple direct foaming process. The new processing route is based on the transition of a surfactant stabilized highly concentrated alkane phase homogeneously distributed in a stabilized aqueous ceramic powder suspension into high performance ceramic foams with porosities up to 90% and cell sizes ranging from 3 to 200 μm. The droplet size distribution of the high alkane phase emulsified suspensions (HAPES) is efficiently controlled by the stirring velocity during emulsification experimentally investigated for varying powder particle contents. Stable foams with tailored structural features can be prepared by adjusting the rheological characteristics of HAPES being dependent on the system and process parameters. The influence of the emulsification stirring velocity on the resulting HAPES droplet size is analysed on the basis of the Taylor model of mechanical shearing describing the stresses responsible for the fragmentation of the droplets. 相似文献