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排序方式: 共有1163条查询结果,搜索用时 15 毫秒
81.
Process development and accurate low‐cost characterization for OLED sealants by using a calcium test
Steffen Hergert Max Linkor Markus Korny Norbert Fruehauf 《Journal of the Society for Information Display》2007,15(6):421-429
Abstract— A calcium measurement setup was built for testing encapsulation especially for OLED applications. This setup is able to measure both reflective and transmissive cells. For the characterization of sealants, a method to compare them with other sealing products will be described. This includes the use of spacers, a homogeneous surface energy, and the geometry of the sealant line. The effects of different geometries will be discussed. The setup was designed to achieve good accuracy at a very reasonable component cost, which will allow other facilities to replicate this setup. Therefore, the construction plan as well as the list of components can be downloaded from our website (Ref. 3). 相似文献
82.
The World Wide Web has turned hypertext into a success story by enabling world-wide sharing of unstructured information and informal knowledge. The Semantic Web targets the sharing of structured information and formal knowledge pursuing objectives of achieving collective intelligence on the Web. Germane to the structure of the Semantic Web is a layering and standardization of concerns. These concerns are reflected by an architecture of the Semantic Web that we present through a common use case. Semantic Web data for the use case is now found on the Web and is part of a quickly growing set of Semantic Web resources available for formal processing. 相似文献
83.
Dorothy K. Hall Jason E. Box Kimberly A. Casey Simon J. Hook Christopher A. Shuman Konrad Steffen 《Remote sensing of environment》2008,112(10):3739-3749
The most practical way to get spatially broad and continuous measurements of the surface temperature in the data-sparse cryosphere is by satellite remote sensing. The uncertainties in satellite-derived LSTs must be understood to develop internally-consistent decade-scale land surface temperature (LST) records needed for climate studies. In this work we assess satellite-derived “clear-sky” LST products from the Moderate Resolution Imaging Spectroradiometer (MODIS) and the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), and LSTs derived from the Enhanced Thematic Mapper Plus (ETM+) over snow and ice on Greenland. When possible, we compare satellite-derived LSTs with in-situ air temperature observations from Greenland Climate Network (GC-Net) automatic weather stations (AWS). We find that MODIS, ASTER and ETM+ provide reliable and consistent LSTs under clear-sky conditions and relatively-flat terrain over snow and ice targets over a range of temperatures from ? 40 to 0 °C. The satellite-derived LSTs agree within a relative RMS uncertainty of ~ 0.5 °C. The good agreement among the LSTs derived from the various satellite instruments is especially notable since different spectral channels and different retrieval algorithms are used to calculate LST from the raw satellite data. The AWS record in-situ data at a “point” while the satellite instruments record data over an area varying in size from: 57 × 57 m (ETM+), 90 × 90 m (ASTER), or to 1 × 1 km (MODIS). Surface topography and other factors contribute to variability of LST within a pixel, thus the AWS measurements may not be representative of the LST of the pixel. Without more information on the local spatial patterns of LST, the AWS LST cannot be considered valid ground truth for the satellite measurements, with RMS uncertainty ~ 2 °C. Despite the relatively large AWS-derived uncertainty, we find LST data are characterized by high accuracy but have uncertain absolute precision. 相似文献
84.
Christian Beecks Steffen Kirchhoff Thomas Seidl 《Multimedia Tools and Applications》2014,71(1):349-362
Retrieving similar images from large image databases is a challenging task for today’s content-based retrieval systems. Aiming at high retrieval performance, these systems frequently capture the user’s notion of similarity through expressive image models and adaptive similarity measures. On the query side, image models can significantly differ in quality compared to those stored on the database side. Thus, similarity measures have to be robust against these individual quality changes in order to maintain high retrieval performance. In this paper, we investigate the robustness of the family of signature-based similarity measures in the context of content-based image retrieval. To this end, we introduce the generic concept of average precision stability, which measures the stability of a similarity measure with respect to changes in quality between the query and database side. In addition to the mathematical definition of average precision stability, we include a performance evaluation of the major signature-based similarity measures focusing on their stability with respect to querying image databases by examples of varying quality. Our performance evaluation on recent benchmark image databases reveals that the highest retrieval performance does not necessarily coincide with the highest stability. 相似文献
85.
Steffen Vojacek Lukas Schulig Nathalie Wössner Norman Geist Prof. Dr. Walter Langel Prof. Dr. Manfred Jung Prof. Dr. Dennis Schade Prof. Dr. Andreas Link 《ChemMedChem》2019,14(8):853-864
Indoles are privileged structures in medicinal and bioorganic chemistry that are particularly well suited to serve as platforms for diversity. Among many other therapeutic areas, the indole scaffold has been used to design aromatic compounds useful to interfere with enzymes engaged in the regulation of substrate acylation status, such as sirtuins. However, the planarity of the indole ring is not necessarily optimal for all target enzymes, especially when functionalization with aromatic side chains is required. Replacement of flat scaffolds by nonplanar molecular cores dominated by sp3 hybridization is a common strategy to avoid the disadvantages associated with poor solubility and high promiscuity, while covering less-well-explored areas of chemical space. Thus, we synthesized fragment-like tetrahydroindoles suitable for fragment-based drug discovery as well as a well-characterized small library intended as multipurpose screening compounds. For proof of principle, these compounds were screened against sirtuins 1–3, enzymes known to be addressable by indoles. We found that 2,6,6-trimethyl-4-oxo-4,5,6,7-tetrahydro-1H-indole-3-carboxamides are potent and selective SIRT2 inhibitors. Compound 16 t displayed an IC50 value of 0.98 μm and could serve as exquisite starting point for hit-to-lead profiling. 相似文献
86.
87.
Parameter-study on the influence of steel fibers and coarse aggregate content on the fresh properties of self-compacting concrete 总被引:7,自引:0,他引:7
Self-compacting concrete (SCC) offers several economic and technical benefits; the use of steel fibers extends its possibilities. Steel fibers bridge cracks, retard their propagation, and improve several characteristics and properties of the concrete. Fibers are known to significantly affect the workability of concrete. Therefore, an investigation was performed to compare the properties of plain SCC and SCC reinforced with steel fibers. Two mixtures of SCC with different aggregate contents were used as reference. Each of the concretes was tested with four types of steel fibers at different contents in order to answer the question to what extent the workability of SCC is influenced. The slump flow, a fiber funnel and the J-ring test were used to evaluate the material characteristics of the fresh concrete. This paper discusses the suitability of the applied test methods and the effect of the coarse aggregate content, the content and type of steel fibers on the workability of SCC. 相似文献
88.
89.
Thomas Schulz Timmy Reimann Arne Bochmann Andre Vogel Beate Capraro Björn Mieller Steffen Teichert Jörg Töpfer 《Journal of the European Ceramic Society》2018,38(4):1600-1607
The sintering behavior and the thermoelectric performance of Ca3Co4O9 multilayer laminates were studied, and a multilayer thermoelectric generator was fabricated. Compacts and multilayer samples with anisotropic microstructure and residual porosity were obtained after conventional sintering at 920 °C, whereas dense and isotropic multilayer samples were prepared by firing at 1200 °C and reoxidation at 900 °C. A hot-pressed sample has a dense and anisotropic microstructure. Samples sintered at 920 °C exhibit low electrical conductivity due to the low density, whereas the Seebeck coefficient is not sensitive to preparation conditions. However, thermal conductivity of multilayers is very low, and, hence acceptable ZT values are obtained. A transversal multilayer thermoelectric generator (TMLTEG) was fabricated by stacking layers of Ca3Co4O9 green tapes, AgPd conductor printing, and co-firing at 920 °C. The TMLTEG has a power output of 3 mW at ΔT = 200 K in the temperature interval of 25 °C to 300 °C. 相似文献
90.
In many fields of materials science it is important to know how densely a particle mixture can be packed. The “packing density”
is the ratio of the particle volume and the volume of the surrounding container needed for a random close packing of the particles.
We present a method for estimating the packing density for spherical particles based on computer simulations only, i.e. without
the need for additional experiments. Our method is particularly suited for particle mixtures with an extremely wide range
of particle diameters as they occur e.g. in modern concrete mixtures. A single representative sample from such mixtures would
be much larger than can be handled on present standard computers. In our hierarchical approach the diameter range is therefore
divided into smaller intervals. Samples from these limited diameter intervals are drawn and their packing density is estimated
from a simulated packing. The results are used to “fill” the interstices in the sample from the next larger particle interval.
To account for the interaction between particles of different sizes we include larger particles into the sample of smaller
ones. The larger ones act as part of the boundary during the packing. Thus we obtain more realistic estimates of how dense
a fraction of particles can be packed within the whole mixture. The focus of this paper is on the divide-and-conquer approach
and on how the simulation results from the fractions can be collected into an overall estimate of the packing density. We
do not go into details of the simulation technique for the single packing. We compare our results to some experimental data
to show that our method works at least as good as the classical analytical models like CPM without the need for any experiments. 相似文献