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991.
992.
Dipl.-lng ChristianSchilling 《光盘技术》2002,(2):45-47
DVD光盘生产相对于传统的CD生产而言对品质控制的依赖更加紧密,丰富的过程控制经验可以使生产合格率不断增加,离线检测和在线检测的合理配合对于整个生产过程是十分重要的,这是一个获得好的收益率的前提。 相似文献
993.
Rosburg Timm; Trautner Peter; Dietl Thomas; Kral Thomas; Elger Christian Erich; Kurthen Martin 《Canadian Metallurgical Quarterly》2005,119(4):876
It is still a matter of debate at which time point faces are recognized as familiar, with some studies claiming a relatively early face recognition and others later effects of familiarity. The authors report on effects of famousness of depicted persons and stimulus repetition on intracranially recorded event-related potentials. Famousness resulted in an increased latency of the N200 component, as well as in an increased amplitude of a later long-lasting potential (N700). In contrast, repetition led to an increased amplitude of the N200 but no increase of its latency. They suppose that the recognition of faces becomes observable within the N200 latency range and that the increased N200 latency reflects a feature processing additional to the holistic face processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
994.
A comprehensive design methodology is proposed in this paper in order to optimise E-field probes used for evaluating the specific absorption ratio within liquid equivalent tissues exposed to radiofrequency signals. Hybrid analysis approaches are investigated, combining both electromagnetic (three dimensional) and circuit simulators. This design environment can therefore be considered for enhancing E-field detectors’ performances in terms of sensitivity, isotropy, dimensions and shape. Comparisons between simulations and measurements are presented and discussed. 相似文献
995.
Antoine Baylaucq Christian Boned Xavier Canet Claus K. Z berg-Mikkelsen Sergio E. Qui ones-Cisneros Honggang Zhou 《Petroleum Science and Technology》2005,23(2):143-157
Viscosity measurements of well-defined mixtures are useful in order to evaluate existing viscosity models. Recently, an extensive experimental study of the viscosity at pressures up to 140 MPa has been carried out for the binary systems methane + n-decane and methane + toluene, between 293.15 and 373.15 K and for several methane compositions. Although very far from real petroleum fluids, these mixtures are interesting in order to study the potential of extending various models to the simulation of complex fluids with asymmetrical components (light/heavy hydrocarbon). These data (575 data points) have been discussed in the framework of recent representative models (hard sphere scheme, friction theory, and free volume model) and with mixing laws and two empirical models (particularly the LBC model which is commonly used in petroleum engineering, and the self-referencing model). This comparative study shows that the average absolute deviation of the models is between 3.8 and 49.8%, and the maximum deviation is between 11.6 and 78.4%, depending on the considered model. 相似文献
996.
Energy system transformation in the electric energy industry encompasses a broad range of changes in how primary energy is produced, transported, converted, priced, and delivered to consumers. Minnesota Power (ALLETE) is responding to these changes by implementing strategies like our EnergyForward resource strategy. EnergyForward describes the transition to a diverse and balanced generation portfolio that meets customers' desires for clean, safe, flexible, and affordable electricity. 相似文献
997.
Graphene has been long thought of as a perfect barrier material due to its impermeability to all gases as well as mechanical and chemical durability. Moreover, graphene layers are transparent and conductive, significantly widening the field of potential applications beyond simple barrier coatings. However, it is very challenging to realize such barriers on a macroscopic scale as immaculate large area films are not available. In this work, a highly effective oxygen gas barrier made from multiple layers of chemical vapor deposited graphene is presented. The individual graphene layers are stacked using a modified polymer‐assisted transfer method, avoiding polymer residue yielding an oxygen‐tight arrangement. A stack of three layers of graphene transmitted 6.9 cm3 m−2 d−1 of O2 which corresponds to 1.10 × 10−17 cm3 cm/cm2 s (cm Hg) when normalized to thickness and pressure. This is several orders of magnitude better than any macroscale graphene coating reported to date and performs on a level that can compete with most modern coatings while being much thinner and conductive. 相似文献
998.
Christian Uhlig Ekrem Guenes Anne S. Schulze Matthias T. Elm Peter J. Klar Sabine Schlecht 《Journal of Electronic Materials》2014,43(6):2362-2370
We have synthesized undoped, Co-doped (up to 5%), and Se-doped (up to 4%) FeS2 materials by mechanical alloying in a planetary ball mill and investigated their thermoelectric properties from room temperature (RT) to 600 K. With decreasing particle size, the undoped FeS2 samples showed higher electrical conductivity, from 0.02 S cm?1 for particles with 70 nm grain size up to 3.1 S cm?1 for the sample with grain size of 16 nm. The Seebeck coefficient of the undoped samples showed a decrease with further grinding, from 128 μV K?1 at RT for the sample with 70-nm grains down to 101 μV K?1 for the sample with grain size of 16 nm. The thermal conductivity of the 16-nm undoped sample lay within the range from 1.3 W m?1 K?1 at RT to a minimal value of 1.2 W m?1 K?1 at 600 K. All doped samples showed improved thermoelectric behavior at 600 K compared with the undoped sample with 16 nm particle size. Cobalt doping modified the p-type semiconducting behavior to n-type and increased the thermal conductivity (2.1 W m?1 K?1) but improved the electrical conductivity (41 S cm?1) and Seebeck coefficient (-129 μV K?1). Isovalent selenium doping led to a slightly higher thermal conductivity (1.7 W m?1 K?1) as well as to an improved electrical conductivity (26 S cm?1) and Seebeck coefficient (110 μV K?1). The ZT value of FeS2 was increased by a factor of five by Co doping and by a factor of three by Se doping. 相似文献
999.
Markus Tauber Christian Wagner Frank Pallas 《e & i Elektrotechnik und Informationstechnik》2014,131(1):33-36
The prevalence of machine-to-machine (M2M) will continue to increase because of the connection and interlinking of services in the domain of critical infrastructures (e.g. “smart grids”, traffic management or surveillance systems). This is leading to a constant rise of required computational and storage resources. As field systems typically offer only limited computing and storage capabilities and as many applications require a global view to integrated data from various devices, a natural location to store data and perform analysis tasks is in the Cloud, where an abundance of flexible resources can be used. However, this results in a number of security and privacy challenges in combination with some legal and technical considerations that need to be addressed. In this paper, we will investigate and categorize the above challenges associated with using the Cloud in a critical infrastructure and M2M context. 相似文献
1000.
Ekrem Güneş Bernadette Landschreiber David Hartung Matthias T. Elm Christian Rohner Peter J. Klar Sabine Schlecht 《Journal of Electronic Materials》2014,43(6):2127-2133
Bismuth nanotubes have been synthesized and successfully included in Bi1?x Sb x nanoalloys to form composite structures. The nanotubes were synthesized by transformation of a β-BiI precursor with n-BuLi solution leading to tubular bismuth structures. The Bi1?x Sb x nanoalloys were produced by ball milling. Three series of composite structures were synthesized by including different fractions (0 wt.%, 3 wt.%, 5 wt.%) of nanotubes in nanoalloys of different composition x. Investigation of thermoelectric and structural properties revealed a decrease of the thermal conductivity of up to 40% for the composites in comparison with alloys without nanotube inclusions. This effect can be attributed to enhanced phonon scattering. Seebeck coefficients and electrical conductivities were both slightly enhanced in the composite series with 3 wt.% nanotube inclusions, leading to enhancement of $$ ZT \ \left(ZT=\frac {(S^2 \sigma)}{\kappa}\,{ {T}}\right) $$ throughout the series compared with the nanoalloy series without nanotube inclusions. 相似文献