1,928 research outputs found
CONSENSUS DEFINITION-BASED CUTOFFS OF HIGH ON-TREATMENT PLATELET REACTIVITY: VALIDATION BETWEEN LIGHT TRANSMITTANCE AND MULTIPLE ELECTRODE AGGREGOMETRIES
Video coding standards
Review by Ashraf A. Kassim, Professor, Department of Electrical & Computer Engineering, and Associate Dean, School of Engineering, National University of Singapore. The book consists of eight chapters of which the first two provide an overview of various video & image coding standards, and video formats. The next four chapters present in detail the Audio & video standard (AVS) of China, the H.264/MPEG-4 Advanced video coding (AVC) standard, High efficiency video coding (HEVC) standard and the VP6 video coding standard (now VP10) respectively. The performance of the wavelet based Dirac video codec is compared with H.264/MPEG-4 AVC in chapter 7. Finally in chapter 8, the VC-1 video coding standard is presented together with VC-2 which is based on the intra frame coding of Dirac and an outline of a H.264/AVC to VC-1 transcoder. The authors also present and discuss relevant research literature such as those which document improved methods & techniques, and also point to other related resources including standards documents, open source software, review papers, and keynote speeches. The numerous projects presented in the later chapters are particularly thought provoking and challenging. These would be useful for readers, especially graduate students, helping them develop a deeper understanding of the standards and also direct them to further research. True to its name, “Video Coding Standards” would serve as a unique resource for researchers, developers and graduate students in the video coding field, enabling them to achieve a good understanding of these current standards including the differences in performance and limitations, as well as keep abreast of latest developments
Seawater-Mediated Solar-to-Sodium Conversion by Bismuth Vanadate Photoanode- Photovoltaic Tandem Cell: Solar Rechargeable Seawater Battery
Conversion of sunlight to chemical energy based on photoelectrochemical (PEC) processes has been considered as a promising strategy for solar energy harvesting. Here, we propose a novel platform that converts solar energy into sodium (Na) as a solid-state solar fuel via the PEC oxidation of natural seawater, for which a Na ion-selective ceramic membrane is employed together with photoelectrode (PE)-photovoltaic (PV) tandem cell. Using an elaborately modified bismuth vanadate-based PE in tandem with crystalline silicon PV, we demonstrate unassisted solar-to-Na conversion (equivalent to solar charge of seawater battery) with an unprecedentedly high efficiency of 8% (expected operating point under I sun) and measured operation efficiency of 5.7% (0.2 sun) and long-term stability, suggesting a new benchmark for low-cost, efficient, and scalable solid solar fuel production. The sodium turns easily into electricity on demand making the device a nature-friendly, monolithic solar rechargeable seawater battery
A Case of Spontaneous Coronary Artery Dissection Healed by Medical Treatment: Serial Findings of Coronary Angiography, Intravascular Ultrasound and Multi-Detector Computed Tomography
Spontaneous coronary artery dissection (SCAD) is an uncommon cause of acute coronary syndrome which may be related to lethal condition. Although several modalities including medical therapy have been suggested, agreement on optimal treatment has not yet been determined. We describe a case of SCAD which was presented as ST-segment elevation myocardial infarction, and treated successfully with medical treatment. Coronary angiography, intravascular ultrasound and multi-detector computed tomography showed the serial changes of this disease entity
Cu Electroless Deposition onto Ta substrates-Application to Create a Seed Layer for Cu Electrodeposition
Copper electroless deposition ELD was investigated for applications that create a seed layer for Cu electrodeposition. On Pd
catalysts formed on the Ta substrates through Sn sensitization–Pd activation, continuous Cu seed layer of 40 nm was electrolessly
deposited in a diluted electrolyte. Dilution of the electrolyte enabled the film to make a thin and conformal layer without oxygen
incorporation, by which the ELD Cu seed had properties comparable to the physical vapor deposited seed layer regarding surface
roughness and resistivity, even after subsequent Cu electrodeposition, and had superior step coverage. Defect-free bottom-up
filling by electrodeposition was achieved on these ELD seed layers.This work was supported by KOSEF through the Research Center
for Energy Conversion and Storage RCECS , Dongbu Electronics
Co. Ltd., and by the Institute of Chemical Processes ICP
Leveling of Superfilled Damascene Cu Film Using Two-Step Electrodeposition
To enhance the compatibility of electrodeposition with the chemical mechanical polishing process, we attempted to prevent step
formation on active areas. In the absence of benzotriazole BTA , the step heights increased with the decrease in the pattern width
and the increase in the pattern density due to the locally condensed accelerator. However, the addition of BTA significantly
suppressed the deposition kinetic through the deactivation of the accelerator. The two-step electrodeposition with modulated
accelerator and BTA concentrations was found to be effective in the retardation of bump formation and the prevention of bumps
from growing without an impact on the superfilling
Algorithm to estimate daily PAR at the ocean surface from GOCI data: description and evaluation
Photosynthetically available radiation (PAR) reaching the ocean surface controls phytoplankton growth, primary productivity, and evolution within marine ecosystems. Therefore, accurate daily PAR estimates are important for a broad range of marine biology and biogeochemistry applications. In this study, hourly data from Geostationary Ocean Color Imager (GOCI), the world’s first geostationary ocean color sensor, was employed to estimate daily mean PAR at the ocean surface around the Korean Peninsula using a budget model based on plane-parallel theory. In situ PAR data collected from two ocean research stations (Socheong-cho and Ieodo) were used to evaluate the accuracy of the GOCI PAR estimates. First, the instantaneous in situ measurements were checked for calibration and exposure errors against Second Simulation of the Satellite Signal in the Solar Spectrum (6S) radiative transfer calculations under the clearest sky conditions and adjusted to eliminate biases. After adjustment, the root-means-square error (RMSE) between 6S and in situ PAR data was reduced from 6.08 (4.81%) and 3.82 (3.93%) mol/m2/day to 2.85 (2.26%) and 1.74 (1.21%) mol/m2/day at the Socheong-cho and Ieodo stations, respectively, and the coefficient of determination R2 was 0.99. Then, the GOCI daily mean PAR estimated by the initial algorithm were corrected using the 2015 adjusted in situ daily PAR measurements collected under clear-sky conditions. The daily mean PAR values derived from GOCI data in all conditions were improved after the correction, with RMSE reduced from 4.58 (8.30%) to 2.57 (4.65%) mol/m2/day and R2 = 0.97. The comparison statistics were similar for 2015 and 2016 combined, with RMSE of 2.52 (4.38%) and mean bias error (MBE) of –0.40 (–0.70%), indicating that the correction was also effective in cloudy conditions. On the other hand, daily PAR estimates from Moderate Resolution Imaging Spectroradiometer (MODIS) and Advanced Himawari Imager (AHI) yielded larger RMSE of 6.24 (10.40%) mol/m2/day and MBE of –2.49 (–4.15%) mol/m2/day (MODIS) and RMSE of 3.71 (6.51%) mol/m2/day and MBE of –2.65 (–4.65%) mol/m2/day (AHI) against in situ measurements. The GOCI-based daily PAR model developed in this study is reliable and suitable for investigating the marine environment around the Korean Peninsula
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