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601.
Jens Lansing Nils Siegfried Ali Sunyaev Alexander Benlian 《The Journal of Strategic Information Systems》2019,28(4):101579
Cloud service certifications (CSCs) are assessed by practitioners to support strategic cloud adoption decisions with the aim to reduce information asymmetries. Both businesses and consumers scrutinize CSCs’ assurances as ex ante signals indicating a cloud provider’s future service quality. While some research has examined the aggregate effects of certifications on decision variables, recipients’ evaluations of certifications and their assurances before making IT-related decisions have received little attention. Furthermore, prior research has predominantly focused on privacy and security assurances in e-commerce certifications. Drawing on signaling theory, we propose that certifications are signals that recipients decompose into a set of fine-grained assurance signals that they weigh to evaluate certifications. We evaluate the responses of 113 company representatives and 317 consumers to a best-worst scaling survey to examine the relative importance these two groups attach to ten assurances from CSCs. Our results show that similar to other online contexts, security and privacy are important assurances, but additional assurances related to availability, the customer friendliness of contracts, and legal compliance are also demanded, particularly by companies. Privacy, security, and availability are most crucial to both companies and consumers, but their relative importance varies substantially between the two groups. Post-hoc subgroup analyses reveal significant differences in assurances’ relative importance for provider and user companies, adopter and non-adopter consumers as well as companies using different types of services and from different industries. Our findings indicate that recipients evaluate certifications as a bundle of signals with varying importance due to recipients’ characteristics and context. With this conceptualization, we contribute to an advanced understanding of the sense-making of certifications and lay out how it influences cloud service adoption theories. Our study has practical implications for certification authorities that design CSCs as well as for providing insights to cloud service providers on customers who draw on CSC assurances when making cloud service adoption decisions. 相似文献
602.
André Becker Ruben Chavez Nils Petermann Gabi Schierning Roland Schmechel 《Journal of Electronic Materials》2013,42(7):2297-2300
Conventional thermoelectric generators (TEGs) use single p- and n-doped legs for thermoelectric energy harvesting. We explore a concept using thermoelectric p–n junctions made from densified silicon nanoparticles. The nanoparticle powder was synthesized in a microwave plasma reactor using silane, diborane, and phosphine as precursors. To achieve a bulk sample with a p–n junction, a layer of boron-doped nanoparticle powder was stacked on a layer of phosphorus-doped powder and compacted by current-activated pressure- assisted densification. To use the p–n structure as a TEG, a temperature gradient was applied along the p–n junction. It is expected that this temperature gradient leads to electron–hole pair generation and separation in the junction, and diffusion of the charge carriers. A reference method was used to characterize the open-circuit voltage of the p–n junction TEG. 相似文献
603.
Nils Reidar B. Olsen 《Canadian Metallurgical Quarterly》2003,129(5):366-372
A three-dimensional CFD model was used to compute the formation of the meandering pattern in an initially straight alluvial channel. The numerical model was based on the finite volume method using an unstructured grid with dominantly hexahedral cells. The k-ε model was used to predict turbulence and the SIMPLE method was used to compute the pressure. The sediment transport was computed as bed load in addition to solving the convection-diffusion equation for suspended sediment transport. The bed changes were calculated and the grid was altered during the computation as channel erosion and deposition caused wetting and drying. The model was tested by comparing with results from physical model studies carried out at Colorado State Univ., Fort Collins, Colo. The results showed successfully the replication of many of the meander characteristics, including secondary currents, cross-sectional profiles, meander planform, meander wavelength, downstream meander migration, and chute formation. 相似文献
604.
Yu Chen Nils P. Halm James E. Braun Eckhard A. Groll 《International Journal of Refrigeration》2002,25(6)
This paper presents the development of a comprehensive simulation model of a horizontal scroll compressor, which combines a detailed compression process model (Chen Y., Halm N., Groll E., Braun J. Mathematical modelling of scroll compressors — part I: compression process modeling, International Journal of Refrigeration 2002;25(6):731–750) and an overall compressor model. In the overall model, compressor components are analyzed in terms of nine different elements. Steady state energy balance equations are established applying the lumped capacitance method. In combination with the detailed compression process model, these equations were implemented into computer code and solved recursively. In this way, the temperature and pressure of the refrigerant in different compressor chambers, the temperature distributions in the scroll wraps, and the temperatures of the other compressor elements can be obtained. Thereafter, power consumption and efficiency of the compressor can be calculated. Tests were used to verify the overall model on a macroscopic basis. Using the simulation program based on the overall compressor model, a parametric study of the scroll compressor was performed, and the effects of internal leakage and heat transfer losses were investigated and some preliminary results were obtained. These results indicate that the comprehensive scroll compressor model is capable of predicting real compressor behavior and useful to the design and optimization of scroll compressors. 相似文献
605.
Fluorine Scan of Inhibitors of the Cysteine Protease Human Cathepsin L: Dipolar and Quadrupolar Effects in the π‐Stacking of Fluorinated Phenyl Rings on Peptide Amide Bonds 下载免费PDF全文
Maude Giroud Dr. Michael Harder Dr. Bernd Kuhn Dr. Wolfgang Haap Dr. Nils Trapp Dr. W. Bernd Schweizer Prof. Dr. Tanja Schirmeister Prof. Dr. François Diederich 《ChemMedChem》2016,11(10):1042-1047
The π‐stacking of fluorinated benzene rings on protein backbone amide groups was investigated, using a dual approach comprising enzyme–ligand binding studies complemented by high‐level quantum chemical calculations. In the experimental study, the phenyl substituent of triazine nitrile inhibitors of human cathepsin L (hCatL), which stacks onto the peptide amide bond Gly67?Gly68 at the entrance of the S3 pocket, was systematically fluorinated, and differences in inhibitory potency were measured in a fluorimetric assay. Binding affinity is influenced by lipophilicity (clog P), the dipole and quadrupole moments of the fluorinated rings, but also by additional interactions of the introduced fluorine atoms with the local environment of the pocket. Generally, the higher the degree of fluorination, the better the binding affinities. Gas phase calculations strongly support the contributions of the molecular quadrupole moments of the fluorinated phenyl rings to the π‐stacking interaction with the peptide bond. These findings provide useful guidelines for enhancing π‐stacking on protein amide fragments. 相似文献
606.
Nils Warnken 《Journal of Phase Equilibria and Diffusion》2016,37(1):100-107
Single crystal superalloys are widely used in high temperature sections of turbines, where they are able to withstand extended exposure to high temperatures. As these alloys are commonly cast and directionally solidified via the Bridgman process, the knowledge of their solidification path is of great importance. This paper gives an overview of aspects of the solidification path in superalloys, as studied experimentally and from a modeling and simulation point of view. The implications of microsegregation, and sequence of phase formation are discussed. Attention is given to the processes leading to the formation of interdendritic γ′, also often referred to as the γ/γ′ eutectic. 相似文献
607.
608.
Dr. Annika Gross Daniel Habig Prof. Dr. Nils Metzler‐Nolte 《Chembiochem : a European journal of chemical biology》2013,14(18):2472-2479
The chemically stabilized somatostatin‐derived cyclic octapeptide octreotate has a number of interesting applications in medicinal chemistry. Here, a number of different organometallic derivatives of octreotate were prepared, and their properties were investigated. Specifically, we report the synthesis and characterization of ruthenocene, ferrocene, and cobaltocenium octreotate derivatives and their fluorophore‐labeled conjugates as well as a dicobalt hexacarbonyl alkyne functionalized octreotate. To provide further insights into their characteristics, the log P values and electrochemical properties of the novel metal conjugates were compared. For biological activity, we determined their toxicity in three different cell lines. Cellular uptake and colocalization of selected compounds were studied by fluorescence microscopy with particular focus on efficiency and specificity of their uptake through the somatostatin receptor SSTR to elucidate the value of the metallocene head group for its potential use as a nontoxic and universal peptide label. 相似文献
609.
The archive of the Nobel Assembly for Physiology or Medicine in Solna, Sweden, is a remarkable repository that contains reports and dossiers of the Nobel Prize nominations of senior and junior physicians from around the world. Although this archive has begun to be used more by scholars, it has been insufficiently examined by historians of surgery. No other German surgeon was nominated as often as Ferdinand Sauerbruch for the Nobel Prize for Physiology or Medicine in the first half of the 20th century. This contribution reconstructs why and by whom Sauerbruch was nominated, and discusses the Nobel committee evaluations of his work. Political factors did not play an obvious role in the Nobel committee discussions, in spite of the fact that Adolf Hitler in 1937 had prohibited all German citizens to accept the Nobel Prize. The main reasons why Sauerbruch ultimately was not considered prize-worthy were that Sauerbruch’s achievements were marked by scientific priority disputes, and that his work was not seen as original enough. 相似文献
610.
Nils Heidler Christoph SchenkGerd Harnisch Stefan RisseGerhard Schubert Ramona EberhardtAndreas Tünnermann 《Precision Engineering》2012,36(1):37-43
Using linear gas bearing guides in a high vacuum environment, the common method to keep the vacuum quality is to exhaust the gas emitted by the bearing pads before leaking into the vacuum chamber. Thereby the exhaust tubes between the guide and the exhaust pumps should interfere with the guide as little as possible while maintaining a flexible connection and a highly effective exhaustion rate. A novel exhaust system that implements these requirements is described within this paper. The major achievement was the realization of two exhaust tubes slidable into one another combined with the known method of non-contact clearance seals, thus enabling an highly efficient and yet disturbance free exhaustion. This setup was developed and characterized at static and dynamic conditions. An analytical model for dimensioning the non-contact seal was worked out and experimentally verified. The number of seal stages and the clearance height were identified as the major impact factors on the leakage rate of the setup. It is concluded that the investigated approach is very suitable for vacuum compatible gas bearing guides since a vacuum level in the order of 10−4 Pa was maintained during the experiments. 相似文献