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11.
In this focused issue on the theme of “Leveraging Values in Global Organizations”, we highlight several prevalent themes on national, organizational and individual values in the literature. We argue that many premises in the literature have been accepted as fact; yet there are still many avenues open to exploration. We present several paradoxes that are often overlooked or lead to inconsistencies in the literature on values. The five articles in this focused issue address these premises and paradoxes, presenting new challenges and opportunities, providing progress and paving the way for future research on leveraging values in global organizations. The selected articles explore values with respect to international alliances and subsidiaries of multinational organizations at the organizational level, among global managers at the group level, and among employees and inpatriates at the individual level of analysis. We trust that readers of this issue will agree that the articles provide novel insights into key issues in the established, yet dynamic, field of research on values in the context of global organizations. 相似文献
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How to calculate symmetries of Petri nets 总被引:1,自引:0,他引:1
Karsten Schmidt 《Acta Informatica》2000,36(7):545-590
Symmetric net structure yields symmetric net behaviour. Thus, knowing the symmetries of a net, redundant calculations can
be skipped. We present a framework for the calculation of symmetries for several net classes including place/transition nets,
timed nets, stochastic nets, self–modifying nets, nets with inhibitor arcs, and many others. Our approach allows the specification
of different symmetry groups. Additionally it provides facilities either to calculate symmetries on demand while running the
actual analysis algorithm, or to calculate them in advance. For the latter case we define and calculate a ground set of symmetries. Such a set has polynomial size and is sufficient for an efficient implementation of the for all symmetries loop and the partition of net elements into equivalence classes. These two constructions are the usual way to integrate symmetries
into an analysis algorithm.
Received 7 July 1997 / 10 August 1999 相似文献
15.
Ada Gavrilovska Sanjay Kumar Srikanth Sundaragopalan Karsten Schwan 《Multimedia Tools and Applications》2007,34(2):179-200
Increased network speeds coupled with new services delivered via the Internet have increased the demand for intelligence and
flexibility in network systems. This paper argues that both can be provided by new hardware platforms comprised of heterogeneous
multi-core systems with specialized communication support. We present and evaluate an experimental network service platform
that uses an emergent class of devices—network processors—as its communication support, coupled via a dedicated interconnect
to a host processor acting as a computational core. A software infrastructure spanning both enables the dynamic creation of
application-specific services on the network processor, mediated by middleware and controlled by kernel-level communication
support. Experimental evaluations use a Pentium IV-based computational core coupled with an IXP 2400 network processor. The
sample application services run on both include an image manipulation application and application-level multicasting.
相似文献
Karsten SchwanEmail: |
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17.
K. Schleisiek J. Aberle S. Jacobi G. Karsten A. Rahn L. Schmidt G. Vanmassenhove A. Verwimp 《Nuclear Engineering and Design》1987,100(3):435-445
The consequences of local cooling disturbances in irradiated fuel pin bundles of Liquid Metal Fast Breeder Reactors (LMFBRs) were investigated in two in-pile experiments in the BR2 reactor at Mol/Belgium. A porous local blockage was used to initiate the fault. This caused severe local fuel pin damage, but there was no fault propagation to major parts of the bundles during four hours of full power operation. If such events occurred in a LMFBR, the delayed neutron detection (DND) signals generated by the fault would be sufficient to initiate reliable automatic shutdown of the reactor. 相似文献
18.
Niuosha Sanaeifar Karsten Mder Dariush Hinderberger 《International journal of molecular sciences》2022,23(13)
We report extended ethanol-induced gelation procedures of bovine serum albumin (BSA) at 37 °C and investigate the release behavior of a spin-labeled naproxen derivative (SL-NPX) from these hydrogels. The macroscopic mechanical properties of these gels during formation were studied using rheology, while a nanoscopic, more molecular view was obtained by analyzing the secondary structure of the protein during gelation via infrared (ATR-IR) spectroscopy. To evaluate the potential use of BSA hydrogels in controlled drug delivery, SL-NPX-BSA interaction was investigated in detail by continuous-wave electron paramagnetic resonance (CW EPR) spectroscopy, which provides information on the interaction of the small drug molecules and the hydrogel. In addition to CW EPR spectroscopy, dynamic light scattering (DLS), which provides insight into the size and nature of released components, was applied to characterize the combined influence of incubation time, ethanol, SL-drug, and BSA concentration on release behavior. It was found that the alteration of initial drug loading percentage, hydrogel incubation time as well as BSA and alcohol concentrations affect and thus tune the release rate of SL-NPX from BSA hydrogels. These results lead to the conclusion that BSA hydrogels as controlled release systems offer a remarkable fine-tuning capability for pharmaceutical applications due to the variety of gelation parameters. 相似文献
19.
Robert Kabbert Karsten Kotte Birgit Cech und Herbert Kunzek 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1996,203(6):512-516
Ethanol pre-treated apple parenchyma cells are dried in a laboratory vacuum dryer. Various ethanol contents (75 to 95% m/m) and moisture contents (2 to 15 g ethanol-water-mixture per g dry mass) of the cells were adjusted before drying and the influence of these factors on drying behaviour as well as the related structural changes are studied. The initial ethanol content was found to have a significant influence on both, drying behaviour and macrostructure of the dried material. In the case of a low initial value, the ethanol content during drying already drops at moisture contents of about 0.5–1.5 g/g. As a consequence the residual particle moisture consists mainly of water at the end of drying. In contrast to high initial ethanol contents, cells at a low initial ethanol content become strongly deformed on drying. The porosity of the dried material also decreases in the latter case, relatively large and stable aggregates are formed and the water binding capacity of the dried product has diminished on a large scale. The initial moisture content influences the drying behaviour especially on applying low initial ethanol contents. If the initial moisture content is reduced the drop of the ethanol content is shifted towards the end of the drying process. The influence of initial moisture content on macrostructure, however, was found to be small compared with the effect of the initial ethanol content. 相似文献
20.
Anubhav Jain Ivano E. Castelli Geoffroy Hautier David H. Bailey Karsten W. Jacobsen 《Journal of Materials Science》2013,48(19):6519-6534
We examine the performance of genetic algorithms (GAs) in uncovering solar water light splitters over a space of almost 19,000 perovskite materials. The entire search space was previously calculated using density functional theory to determine solutions that fulfill constraints on stability, band gap, and band edge position. Here, we test over 2500 unique GA implementations in finding these solutions to determine whether GA can avoid the need for brute force search, and thereby enable larger chemical spaces to be screened within a given computational budget. We find that the best GAs tested offer almost a 6 times efficiency gain over random search, and are comparable to the performance of a search based on informed chemical rules. In addition, the GA is almost 10 times as efficient as random search in finding half the solutions within the search space. By employing chemical rules, the performance of the GA can be further improved to approximately 12–17 better than random search. We discuss the effect of population size, selection function, crossover function, mutation rate, fitness function, and elitism on the final result, finding that selection function and elitism are especially important to GA performance. In addition, we determine that parameters that perform well in finding solar water splitters can also be applied to discovering transparent photocorrosion shields. Our results indicate that coupling GAs to high-throughput density functional calculations presents a promising method to rapidly search large chemical spaces for technological materials. 相似文献