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91.
Aleksandra Sowa 《Datenschutz und Datensicherheit - DuD》2007,31(6):441-445
Mit steigender Durchdringung der Kreditinstitute mit der IT und immer st?rker werdender Abh?ngigkeit des Bankgesch?fts von
dem Netz steigen auch die mit der Verletzbarkeit und Ausfall der IT-Systeme verbundenen Risiken. Für die IT-Revision bedeutet
dies ein wachsendes Engagement im Rahmen von Sicherheitsprüfungen und- Beratungen, um diesen Risiken in angemessener Weise
zu begegnen. Durch Einsatz geeigneter Prüfungsmethodik und hoher fachlichen Qualifikationen der Revisoren k?nnen die Sicherheitsprüfungen
zu einer wichtigen Erfolgsdeterminante eines Instituts werden. 相似文献
92.
Nowadays many leading companies understand that creating outstanding customer value is necessary to achieving sustainable market success. The main problem discussed in this article is the examination of factors affecting perceived value, emphasizing the relationship between perceived price and perceived value. Based on literature and their own findings, the authors designed a model of relationships between researched factors. This model was tested using structural equation modeling. The results reflected that statistically significant relationships exists and that perceived price has direct as well as indirect efects on perceived product value. 相似文献
93.
Aleksandra Turkovi Bojan Orel Magdy Lu
i-Lav
evi Pavo Dub
ek Zorica Crnjak Orel Sigrid Bernstorff 《Solar Energy Materials & Solar Cells》2007,91(14):1299-1304
Cerium vanadate films on glass substrate were obtained by sol–gel process. The morphology of these nanostructured and porous films was studied by grazing-incidence small-angle X-ray scattering (GISAXS) at synchrotron ELETTRA, Trieste, Italy. The aim of the GISAXS study was to investigate the changes in grain sizes due to the temperature evolution with three different time intervals (5, 15 and 30 min) of annealing at 673 K. We found that the effects of the different times of annealing are different for surface and bulk properties of this V/Ce oxide. 相似文献
94.
Stefan Goszczyski Jan Szymanowski Aleksandra Borowiak-Resterna 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1981,31(1):333-340
The study of copper extraction shows that the position of the chain (5 or 4′) does not influence the statics of copper extraction from ammonia solutions by alkyl derivatives of 2-hydroxybenzophenone oxime. Acid solutions of 2-hydroxy-4′-n-nonylbenzo-phenone oxime can extract more copper than 2-hydroxy-5-n-nonylbenzophenone oxime, but less than 2-hydroxy-5-n-alkylbenzaldehyde oxime. 相似文献
95.
Aleksandra Lazarenko Lyudmila Vovchenko Lyudmila Matzui Victor Kozachenko Yuriy Prylutskyy Peter Scharff Uwe Ritter 《Polymer Composites》2011,32(1):14-17
This study was performed to measure the thermal diffusivity of different types of nanocarbon composites. Thermoexfoliated graphite (TEG), ultrasonically dispersed TEG, and multiwalled carbon nanotubes were used as fillers in epoxy polymer matrixes. The nanocarbon filler content was 1–10 wt%. The temperature dependence of the thermal conductivity and the heat capacity were extensively characterized in the temperature range between 150 and 425 K. For this purpose, the thermal diffusivity of the composites was investigated by two experimental methods: dynamic λ‐calorimeter and photoacoustic. The comparative analysis of thermal diffusivity of compacted TEG samples with different densities and of nanocarbon‐epoxy with different filler content was carried out. It was found that for the composites with a low distribution of the nanocarbon filler, the thermal diffusivity increases and that the value is determined by the structural and morphological properties of the filler. The orientation function for the TEG‐epoxy composites and the compact TEG samples differs due to the epoxy matrix that reduced anisotropy of the composite. POLYM. COMPOS., 2011. © 2010 Society of Plastics Engineers 相似文献
96.
Osmotic treatment (OT) has been applied to infuse phenolic compounds into a model food. Two commercial grape extracts were used as a source of phenolics, a grape seed extract (GSE) and a white grape marc extract (WGME). Three different concentrations of total phenolics were applied with and without presence of osmo-active solute (50 g/100 g and 0 g/100 g of sucrose) in the osmotic solution (OS). With a 50 g/100 g sucrose and a total phenolic content in OS ranging from 3 g/L to 15 g/L and operating time up to 8 h, the final total phenolic content in the osmo-treated model food was between 815 mg GAE/kg and 7176 mg GAE/kg. That is between the 0.5 and 1.5 times higher than that of the richest fruits. A soaking process with the same phenolic content but with no sucrose in OS led to a total phenolic content in the model food that was between 80% and 100% higher.Mass transfer of the major phenolics infused into the model food during OT and soaking process was characterized considering the diffusional approach and Peleg's model. Progress of total and individual phenolic content fitted well both models with the exception of the flavan-3-ol dimer concentration. 相似文献
97.
Aleksandra Buzarovska Anita Grozdanov M. Avella G. Gentile M. Errico 《应用聚合物科学杂志》2009,114(5):3118-3124
Nanocomposites, based on a poly(hydroxybutyrate‐co‐hydroxyvalerate) (PHBV) matrix and titanium dioxide (TiO2) nanoparticles and fabricated with a solvent‐casting technique, were characterized with differential scanning calorimetry, thermogravimetric analysis, scanning electron microscopy, and Fourier transform infrared spectroscopy. The content of TiO2 nanoparticles varied between 0.5 and 10 wt %. Degradation studies, including hydrolytic degradation in a strong base medium (1N NaOH) and degradation under ultraviolet light at 365 nm, were performed. It was confirmed that the inorganic filler had no great influence on thermal properties such as the melting and crystallization temperatures. Improved degradation temperatures were also confirmed with the increase in the filler content. Degradation observations confirmed significant increases in hydrolytic erosion with the filler content increasing in comparison with the degradation of a pure PHBV film. Also, the photocatalytic activity of the inorganic filler TiO2 in all investigated composites [irradiated at λ = 365 nm and immersed in a liquid medium (H2O)] was evaluated. The degraded samples were analyzed with Fourier transform infrared spectroscopy, which confirmed their increased crystallinity. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
98.
Marleen Morbee Antoni Roca Josep Prades-Nebot Aleksandra Pižurica Wilfried Philips 《Signal, Image and Video Processing》2008,2(2):129-140
In some video coding applications, it is desirable to reduce the complexity of the video encoder at the expense of a more
complex decoder. Wyner–Ziv (WZ) video coding is a new paradigm that aims to achieve this. To allocate a proper number of bits
to each frame, most WZ video coding algorithms use a feedback channel, which allows the decoder to request additional bits
when needed. However, due to these multiple bit requests, the complexity and the latency of WZ video decoders increase massively.
To overcome these problems, in this paper we propose a rate allocation (RA) algorithm for pixel-domain WZ video coders. This
algorithm estimates at the encoder the number of bits needed for the decoding of every frame while still keeping the encoder
complexity low. Experimental results show that, by using our RA algorithm, the number of bit requests over the feedback channel—and
hence, the decoder complexity and the latency—are significantly reduced. Meanwhile, a very near-to-optimal rate-distortion
performance is maintained.
This work has been partially supported by the Spanish Ministry of Education and Science and the European Commission (FEDER)
under grant TEC2005-07751-C02-01.
A. Pižurica is a postdoctoral research fellow of FWO, Flanders. 相似文献
99.
100.
Antioxidant capacity,total phenolics,glucosinolates and colour parameters of rapeseed cultivars 总被引:2,自引:0,他引:2
Aleksandra Szydłowska-Czerniak Iwona Bartkowiak-Broda Igor Karlović György Karlovits Edward Szłyk 《Food chemistry》2011
The antioxidant capacity of twenty nine rapeseed varieties was determined by using ferric reducing antioxidant power (FRAP) and 2,2′-diphenyl-1-picrylhydrazyl (DPPH) methods. Mean FRAP (3190–6326 μmol Trolox/100 g) and DPPH (3194–6346 μmol Trolox/100 g) values for methanolic extracts of rapeseed cultivars did not differ significantly. Moreover, the total content of phenolics (756–1324 mg sinapic acid/100 g), glucosinolates (4.2–87.5 μmol/g, respectively), erucic acid (0.0–56.1%) and colour parameters of the studied rapeseed cultivars were analysed. Antioxidant capacity determined by FRAP and DPPH methods correlated significantly with total phenolic content (TPC) in rapeseed cultivars (r = 0.9332, 0.9339, p < 0.001). Also, significant, inverse correlations were found between antioxidant capacity, total phenolics and luminosity (L∗) or red colour intensity (a∗) of rapeseed cultivars. Principal component analysis (PCA) allowed the rapeseed varieties to be differentiated based on their antioxidant capacities, total amounts of phenolics, glucosinolates, erucic acid and colour parameters. 相似文献