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141.
Peter Maskell Torben Pedersen Bent Petersen Jens Dick-Nielsen 《Industry and innovation》2007,14(3):239-257
A corporation's offshore outsourcing may be seen as the result of a discrete, strategic decision taken in response to an increasing pressure from worldwide competition. However, empirical evidence of a representative cross-sector sample of international Danish firms indicates that offshore sourcing in low-cost countries is best described as a learning-by-doing process in which the offshore outsourcing of a corporation goes through a sequence of stages towards sourcing for innovation. Initially, a corporation's outsourcing is driven by a desire for cost minimization. Over a period of time the outsourcing experience lessens the cognitive limitations of decision-makers as to the advantages that can be achieved through outsourcing in low-cost countries: the insourcer/vendor may not only offer cost advantages, but also quality improvement and innovation. The quality improvements that offshore outsourcing may bring about evoke a realization in the corporation that even innovative processes can be outsourced. 相似文献
142.
Andrey Sarikov Jens Schneider Martin Muske Ina Sieber Stefan Gall 《Thin solid films》2007,515(19):7465-7468
The aluminium-induced layer-exchange process allows to grow thin large-grained polycrystalline Si films on foreign substrates. A characteristic feature of these films is the preferential (100) orientation of Si grains, favourable for subsequent epitaxial thickening at low temperatures. In this work, a model based on the preferential nucleation is proposed, which elucidates a possible origin of the preferential (100) orientation and its sensitivity to the preparation and process conditions. The probability of Si nuclei to have respective orientation is attributed to the nucleation barrier, i.e. the critical value of the change of the Gibbs energy during nucleation. The preferential orientation is formed statistically by the nuclei having the lowest nucleation barriers. 相似文献
143.
Jens Oldeland Dirk Wesuls Norbert Jürgens 《International journal of remote sensing》2013,34(20):6459-6479
Databases on plant traits as well as the availability of global coverage of high spatial and spectral resolution remote-sensing data are constantly growing. However, little effort has been made to analyse the relationship between plant traits and remote-sensing data while simultaneously taking species identity and abundance into consideration. We correlated quantitative and qualitative plant traits from a dwarf shrub savanna in Namibia, with spectral indices derived from two hyperspectral sensors, HyMap and the Compact High Resolution Imaging Spectrometer Project for On-Board Autonomy (CHRIS-PROBA), which differ in their spatial and spectral resolution. We used RLQ analysis and the fourth-corner statistic, which are two three-table ordination approaches that circumvent the so-called fourth-corner problem. A higher spatial resolution helped to identify trait–index correlations linked to vegetation structure, while a lower spatial resolution pointed at traits linked to vegetation cover. A higher spectral resolution did not improve the relationships between spectral indices and plant traits. However, continuous hyperspectral signatures allowed for the calculation of spectral indices that make use of the detailed spectra allowing for more sophisticated spectral indices. We propose RLQ and the fourth-corner statistic as suitable tools for the remote sensing and Earth observation community that allow the direct correlation of trait databases with remotely sensed information. 相似文献
144.
From a production logistics point of view, micro production systems need special methods due to their special requirements
and characteristics. In this paper a new approach for the assessment of different investment scenarios during the planning
period with integrated cost simulation is presented. In particular, the use of single-purpose and multi-purpose machines and
the cost effectiveness of function integration are examined. Thereby alternative machine pool configurations and optimal costs
can be analysed, determined and taken into consideration for investment decisions. 相似文献
145.
In a longitudinal study, Q-sort patterns of German preschool children were analyzed for personality prototypes and related to developmental outcomes up to age 12. Q-factor analyses confirmed 3 prototypic patterns that showed a high continuity and cross-judge consistency; were similar to those found for North American, Dutch, and Icelandic children; and can be interpreted as resilient, overcontrolled, and undercontrolled. Relations reported by R. W. Robins, O. P. John, A. Caspi, T. E. Moffitt, & M. Stouthamer-Loeber (1996) between these 3 patterns and the Big Five were fully replicated. Growth curve analyses showed that the 3 patterns predicted important developmental outcomes in both the social and the cognitive domains. Evidence was found for both traits and types: A continuous dimension of resiliency bifurcates in its lower part into two relatively discrete personality types, overcontrollers and undercontrollers. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
146.
Jens Peter Hermes 《Electrochimica acta》2009,54(17):4258-2989
Doping front migration is a recently discovered effect occurring in sandwich structures composed of intrinsically conductive polymers. A system based on chemical or electrochemical doping is capable of controlling an integrated display and modifying the electrical resistance of the conductive polymer. The effect does not require a battery and is capable of monitoring time and temperature exposure. Low-cost devices using doping front migration could be the basis of a new class of smart labels for applications such as electronic “best before” labels on food and drink. 相似文献
147.
Hugo Ahlm Grønlund Charlotta Löfström Jens Bue Helleskov Jeffrey Hoorfar 《Food Analytical Methods》2010,3(2):116-119
Validation of PCR thermocycler performance is crucial to obtain reliable results. In this study, infrared (IR) thermography
was evaluated as a novel validation tool. After stabilisation, no significant difference in the temperatures recorded using
thermography and a reference block-based system was found. By employing IR thermography, information about the length of the
time until temperature stabilisation in the sample could be obtained. This study shows the potential of using IR thermography
for validation of thermocyclers. 相似文献
148.
Volkmar Lankau Hans-Peter Martin Renate Hempel-Weber Niels Oeschler Alexander Michaelis 《Journal of Electronic Materials》2010,39(9):1809-1813
SiC-B4C composites with various values of SiC-to-B4C ratio and grain size were fabricated by pressureless sintering. This paper presents the results of current investigations
of this composite material. This includes the parameters of manufacture (shrinkage, density, and open porosity), thermoelectric
properties (electrical and thermal conductivity, and thermopower), and material characterization (x-ray diffraction, scanning
electron microscopy, oxidation resistance, and thermal expansion). The results indicate high potential of this composite as
an alternative material for thermoelectric applications at high temperatures. The Seebeck coefficient of the composite was
higher than that of the single-component materials B4C and SiC and reached 400 μV/K at 500°C. 相似文献
149.
150.
Wrosch Carsten; Miller Gregory E.; Lupien Sonia; Pruessner Jens C. 《Canadian Metallurgical Quarterly》2008,27(6):685
Objective: This study examined whether the association between cortisol secretion and changes in physical health symptoms would depend on other factors in a person's life. The authors expected that physical health effects would emerge particularly when cortisol disturbances co-occur in the context of high levels of trait negative affect or poor sleep. Design: Physical symptoms, diurnal cortisol secretion, affective tendencies, and sleep efficiency were assessed in a 2-yr longitudinal study of 184 older adults. Main Outcome Measure: Two-year changes in physical symptoms. Results: High cortisol levels were associated with increases in physical symptoms, but only among participants who experienced high negative affect and poor sleep. Conclusion: Elevated levels of cortisol secretion contribute to older adults' physical symptoms if they co-occur in the context of other emotional and behavioral problems. By contrast, cortisol disturbances may not influence physical symptoms among people who are emotionally well or engage in efficient sleep behaviors. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献