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11.
The molded electrode test system (METS) test has long been used with flexible poly(vinyl chloride) (PVC) electrical insulation. However, there are many questions regarding its precision and accuracy, as there is no industry‐accepted standard regarding this test. This paper aims to answer some of these questions in terms of the measurement precision as well as the ability of the test to predict wet electrical performance on wire. A repeatability study was conducted on flexible PVC compound where 10 samples were produced and tested under identical conditions. The mean insulation resistance was (550 MΩ)/(305 m) with a standard deviation of (120 MΩ)/(305 m). As the thickness of the insulation increased, the insulation resistance decreased. Furthermore, the study showed that there was no correlation between the METS test and wet volume resistivity, while there was some correlation with wet insulation resistance (IR) at high temperature, though the ability to predict wet IR from the METS test was limited. J. VINYL ADDIT. TECHNOL., 18:178–183, 2012. © 2012 Society of Plastics Engineers  相似文献   
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Microsystem Technologies - High isolation and low insertion loss are the key design parameters for the NEMS switch at high frequency. The comprehensive study of radio frequency (RF) performance...  相似文献   
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Neural Computing and Applications - This study presents a novel implementation of evolutionary heuristics through backtracking search optimization algorithm (BSA) for accurate, efficient and robust...  相似文献   
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In this article, a wideband circularly polarized rectangular dielectric resonator antenna (RDRA) with broadside radiation characteristics has been proposed. By using modified ground plane having an F‐shaped slot, the proposed structure able to generates three sets of modes i.e., fundamental as well as higher order modes. To obtained circular polarization, an orthogonal mode (TE113) in the RDRA has been generated by using the F‐shaped slot on the modified ground plane. The resonance frequency of fundamental mode (TE111) in the rectangular dielectric resonator (DR) has been calculated by using dielectric waveguide model method. The same has been confirmed through E‐field distribution in RDRA. Here, wide axial ratio (AR) bandwidth of the proposed antenna is due to the generation of and modes. It is observed that input impedance bandwidth has been broadening with a pair of excited modes ( and modes) in the proposed antenna structure. All these modes have been excited and merged to form a wide input impedance bandwidth and wide AR bandwidth of the designed antenna. The proposed antenna shows measured input reflection coefficient (S11 < ?10 dB) of 50.55% and measured AR bandwidth (AR < 3 dB) of 14.28%. The designed antenna shows left‐handed circular polarization in broadside direction and offering an average gain and radiation efficiency of 4.29 dBic and 92.22% respectively.  相似文献   
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As computational clusters increase in size, their mean time to failure reduces drastically. Typically, checkpointing is used to minimize the loss of computation. Most checkpointing techniques, however, require central storage for storing checkpoints. This results in a bottleneck and severely limits the scalability of checkpointing, while also proving to be too expensive for dedicated checkpointing networks and storage systems. We propose a scalable replication-based MPI checkpointing facility. Our reference implementation is based on LAM/MPI; however, it is directly applicable to any MPI implementation. We extend the existing state of fault-tolerant MPI with asynchronous replication, eliminating the need for central or network storage. We evaluate centralized storage, a Sun-X4500-based solution, an EMC storage area network (SAN), and the Ibrix commercial parallel file system and show that they are not scalable, particularly after 64 CPUs. We demonstrate the low overhead of our checkpointing and replication scheme with the NAS Parallel Benchmarks and the High-Performance LINPACK benchmark with tests up to 256 nodes while demonstrating that checkpointing and replication can be achieved with a much lower overhead than that provided by current techniques. Finally, we show that the monetary cost of our solution is as low as 25 percent of that of a typical SAN/parallel-file-system-equipped storage system.  相似文献   
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Multimedia Tools and Applications - Automated bank cheque verification using image processing is an attempt to complement the present cheque truncation system, as well as to provide an alternate...  相似文献   
19.
A compact dual‐band CPW–fed metamaterial inspired antenna using Composite Right/Left Handed (CRLH) resonant approach is presented in this article. The antenna is designed such that it can be operated in series resonant mode where resonance behavior is characterized by series LC parameters. Proposed antenna comprises two annular ring resonators connected with the signal patch intended to excite the higher order modes. This results extension of second band from 51.4% (fc = 6.92 GHz) to 69.2% (fc = 7.35 GHz). In addition to that proposed antenna shows compact nature with an electrical size of 0.14 λ0 × 0.21 λ0 × 0.01 λ0 at f0 = 2.18 GHz. The antenna is operating over 2.14–2.23 GHz, 4.81–9.90 GHz with simulated peak gain of 0.66 and 4.44 dB, respectively. Simulated radiation efficiencies of proposed antenna are 69.8 and 94.1% throughout first and second band, respectively. To examine the resonance and radiation characteristics prototype is fabricated and measured. Observed experimental results are in good agreement with those simulated one. These characteristics makes this antenna is a good candidate for modern wireless communication systems such as Bluetooth, WLAN/Wi‐Fi band. © 2016 Wiley Periodicals, Inc. Int J RF and Microwave CAE 26:435–441, 2016.  相似文献   
20.
This article presents a new dual C‐shaped rectangular dielectric resonator (DR) based antenna for generation of wideband circularly polarized (CP) radiation. The proposed antenna comprises of a pair of C‐shaped rectangular dielectric DR and a metal strip with a coaxial probe. By utilization of a metal strip at the side surface of C‐shaped rectangular DR, the wideband CP radiation is achieved from the proposed dielectric resonator antenna (DRA). Fundamental orthogonal modes (TExδ11 and TEy1δ1) are excited using the rectangular DRA with a metal strip for the generation of CP fields. The proposed antenna with dual C‐shaped rectangular CP DRA provides the measured ?10 dB reflection coefficient bandwidth of 30.07% (3.22 GHz‐4.36 GHz) with measured 3‐dB axial ratio bandwidth of 14.81% (3.25 GHz‐3.77 GHz) at the boresight. The proposed antenna covers the useful Wi‐MAX band.  相似文献   
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