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191.
Heuristische Erlösprognosen für die Bewertung von Geschäftsmodellen im Application Service Providing
Prof. Dr. Hubert Dechant Univ.-Prof. Dr. Dirk Stelzer Univ.-Prof. Dr. Ralf Trost 《WIRTSCHAFTSINFORMATIK》2004,46(6):446-458
Several problems complicate the assessment of enterprises that cooperate with other firms in developing and distributing bundled goods. Revenue forecasts are particularly challenging. Cooperating suppliers must estimate and model future prices and sales volumes. They have to agree on a ratio of distribution for jointly generated revenues. Furthermore, they must compare different value chain configurations and assess consequences for the distribution of revenues. We propose a heuristic method that helps to forecast revenues for bundled goods. We demonstrate the heuristic method with the example of Application Service Providing. 相似文献
192.
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194.
We investigate the sensitivity of production rates (activities) of the regulatory proteins CI (repressor) and Cro at the right operator (OR) of bacteriophage lambda. The DNA binding energies of CI, Cro, and RNA polymerase are perturbed to check the uncertainty of the activity, due to the experimental error, by means of a computational scattering method according to which the binding energies are simultaneously chosen at random around the literature values, with a width corresponding to the experimental error. In a grand canonical ensemble, with the randomly drawn protein-DNA binding energies as input, we calculate the corresponding activities of the promoters PRM and PR. By repeating this procedure we obtain a mean value of the activity that roughly corresponds to wild-type (unperturbed) activity. The standard deviation emerging from this scheme, a measure of the sensitivity due to experimental error, is significant (typically >20% relative to wild-type activity), but still the promoter activities are sufficiently separated to make the switch feasible. We also suggest a new, compact way of presenting repressor and Cro data. 相似文献
195.
Ralph Schöpke Roland Koch Sylke Mangold Volker Preuß Ralf Regel Angelika Striemann 《Grundwasser》2006,11(4):270-275
Sulfate-reducing processes were initiated in an aquifer with AMD-laden groundwater orthogonally to the located main groundwater flow direction. Groundwater was intermittently circulated between two wells. Substrate (methanol) and nutrients were added to this flow. After one year a sulphate-reducing reactor was formed in the aquifer, that precipitated FeS and decreased the acidity. These effects could still be observed one year after cessation of substrate amendment. 相似文献
196.
Verena Liebau-Kunzmann Claudia Fasel Robert Kolb Ralf Riedel 《Journal of the European Ceramic Society》2006,26(16):3897-3901
Lithium containing silicon carbonitride ceramics (SiCN:Li) were synthesized via precursor-to-ceramic-transformation of Li-containing (poly)silazanes. The precursors were obtained by lithiation of the model compound 2,4,6-trimethyl-2,4,6-trivinylcyclotrisilazane and of a commercial poly(organosilazane) VL20® with n-butyllithium in different molar ratios. According to Raman spectroscopic measurements, lithiation takes place at the NH groups of the molecular organosilazane structure. If the amount of n-BuLi exceeds the stoichiometric amount of NH groups, addition of n-BuLi at the vinyl groups (attached as substituents at the Si atoms of the silazane) occurs. Thermal analysis coupled with in situ mass spectrometry evidenced the loss of methane and hydrogen as the main gaseous by-products formed during the precursor-to-ceramic-transformation. The ceramization process is completed at 1100 °C in argon and yielded Li-containing silicon carbonitride, SiCN:Li. X-ray powder diffraction revealed that the resulting SiCN:Li ceramics were basically amorphous and contained LiSi2N3 as a crystalline phase with increasing amount of Li. Possible applications of the new SiCN:Li ceramics are seen in the field of Li-ion batteries as alternative anode or solid electrolyte material. 相似文献
197.
René-Maxime Gracien Sarah C. Reitz Marlies Wagner Christoph Mayer Steffen Volz Stephanie-Michelle Hof Vinzenz Fleischer Amgad Droby Helmuth Steinmetz Sergiu Groppa Elke Hattingen Johannes C. Klein Ralf Deichmann 《Magma (New York, N.Y.)》2017,30(1):75-83
Objective
Proton density (PD) mapping requires correction for the receive profile (RP), which is frequently performed via bias-field correction. An alternative RP-mapping method utilizes a comparison of uncorrected PD-maps and a value ρ(T1) directly derived from T1-maps via the Fatouros equation. This may be problematic in multiple sclerosis (MS), if respective parameters are only valid for healthy brain tissue. We aimed to investigate whether the alternative method yields correct PD values in MS patients.Materials/methods
PD mapping was performed on 27 patients with relapsing-remitting MS and 27 healthy controls, utilizing both methods, yielding reference PD values (PDref, bias-field method) and PDalt (alternative method).Results
PDalt-values closely matched PDref, both for patients and controls. In contrast, ρ(T1) differed by up to 3 % from PDref, and the voxel-wise correlation between PDref and ρ(T1) was reduced in a patient subgroup with a higher degree of disability. Still, discrepancies between ρ(T1) and PDref were almost identical across different tissue types, thus translating into a scaling factor, which cancelled out during normalization to 100 % in CSF, yielding a good agreement between PDalt and PDref.Conclusion
RP correction utilizing the auxiliary parameter ρ(T1) derived via the Fatouros equation provides accurate PD results in MS patients, in spite of discrepancies between ρ(T1) and actual PD values.198.
199.
This study operationalizes an existing concept for the categorization of governance approaches for projects. For that the concept's four governance paradigms, based on the overlay of the shareholder–stakeholder orientation with the behavior–outcome control of a project's parent organization are measured. The measurement dimensions were derived from the intersection of governance and organization theory with project management theory, thereby addressing those areas of corporate governance and organizational control that extend into projects. The application of the measurement construct, its validity and reliability are tested through a world-wide questionnaire with 478 responses. Analysis of the responses shows the differences in governance structures for projects by country, project size, and project type. The results are important for managers developing governance structures and academics developing governance theories. 相似文献
200.