746 research outputs found
Design and Implementation of UWB CPW-Fed Planar Monopole Antenna with Dual Band Rejection Characteristics
Quantification of The Performance of CMIP6 Models for Dynamic Downscaling in The North Pacific and Northwest Pacific Oceans
Selecting a reliable global climate model as the driving forcing in simulations with dynamic downscaling is critical for obtaining a reliable regional ocean climate. With respect to their accuracy in providing physical quantities and long-term trends, we quantify the performances of 17 models from the Coupled Model Inter-comparison Project Phase 6 (CMIP6) over the North Pacific (NP) and Northwest Pacific (NWP) oceans for 1979–2014. Based on normalized evaluation measures, each model’s performance for a physical quantity is mainly quantified by the performance score (PS), which ranges from 0 to 100. Overall, the CMIP6 models reasonably reproduce the physical quantities of the driving variables and the warming ocean heat content and temperature trends. However, their performances significantly depend on the variables and region analyzed. The EC-Earth-Veg and CNRM-CM6-1 models show the best performances for the NP and NWP oceans, respectively, with the highest PS values of 85.89 and 76.97, respectively. The EC-Earth3 model series are less sensitive to the driving variables in the NP ocean, as reflected in their PS. The model performance is significantly dependent on the driving variables in the NWP ocean. Nevertheless, providing a better physical quantity does not correlate with a better performance for trend. However, MRI-ESM2-0 model shows a high performance for the physical quantity in the NWP ocean with warming trends similar to references, and it could thus be used as an appropriate driving forcing in dynamic downscaling of this ocean. This study provides objective information for studies involving dynamic downscaling of the NP and NWP oceans
Creep and Oxidation Behaviors of Alloy 617 in Air and Helium Environments at 1173K
AbstractCreep and oxidation behaviours of Alloy 617 in air and helium (He) environments at 1173K were comparatively investigated under different applied stress levels. There were no large differences in the shapes of the creep curves between the air and He environments. Creep rupture time in the He environment was shorter than that in air. The outer Cr-oxide thickness of the air specimens was thicker in short-tested duration than that of the He specimens. However, in the long- tested duration over 3,000h, the Cr-oxide thickness in the He environment was larger than in air. It was found that creep rupture life was closely related to the thickness of the outer Cr-oxide layer, because the form of the outer Cr-rich oxide layer brings about the Cr-depleted region which may deteriorate material strength or creep life
DeeLeMa: Missing information search with Deep Learning for Mass estimation
We present DeeLeMa, a deep learning network to analyze energies and momenta
in particle collisions at high energy colliders, especially DeeLeMa is
constructed based on symmetric event topology, and the generated mass
distributions show robust peaks at the physical masses after the combinatoric
uncertainties, and detector smearing effects are taken into account. DeeLeMa
can be widely used in different event topologies by adopting the corresponding
kinematic symmetries
Influence of Friction Stir Welding on Mechanical Properties of Butt Joints of AZ61 Magnesium Alloy
In this study, the effect of heat input on the mechanical properties and fracture behaviors of AZ61 magnesium alloy joints has been studied. Magnesium alloy AZ61 plates with thickness of 5 mm were welded at different ratios of tool rotational speed to welding speed (ω/ν). The average ultimate tensile strength of all weld conditions satisfying a ω/ν ratio of 3 reached 100% of the strength of the base material. Fractures occurred at the interface between the thermomechanical affected zone at advancing side and the stir zone in all welded specimens. From the scanning electron microscope and electron backscatter diffraction analysis, it was determined that the interface between the thermomechanical affected zone and the stir zone, which is the region where the grain orientation changes, was the weakest part; the advancing side region was relatively weaker than the retreating side region because the grain orientation change occurred more dramatically in the advancing side region
TMSI Allocation Mechanism Using a Secure VLR Authorization in the GSM System
Abstract. GSM is the most popular standard for mobile phones in the world. In spite of the tremendous market growth, however, the GSM system has the fatal security problems in TMSI allocation protocol. These problems are right user authentication and location privacy. In this paper, we propose the secure TMSI allocation mechanism using the certification concept to solve these problems. The proposed mechanism provides partial anonymity, which has been rarely provided in the other approaches. Also we propose the modified mechanism to reduce TMSI allocation procedure without changing of the architecture of the original GSM system
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