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51.
Recently, Page and Vercauteren proposed a fault attack on pairing algorithms and two countermeasures against such an attack. The countermeasure uses either a random scalar or a random point to blind the input points. To defeat the countermeasure using a random point, we utilize the point addition formula on an elliptic curve. As a result, we successfully defeat the countermeasure using a random point.  相似文献   
52.
A novel simplified fabrication method of a very high density p-channel trench gate power MOSFET using four mask layers and nitride/TEOS sidewall spacers is realized. The proposed process showed improved on-resistance characteristics of the device with increasing cell density and the cost-effective production capability due to the lesser number of processing steps. By using this process technique, a remarkably increased high density (100 Mcell/inch2) trench gate power MOSFET with a cell pitch of 2.5 μm could be effectively realized. The fabricated device had a low specific on-resistance of 1.1 mΩ-cm2 with a breakdown voltage of -36 V  相似文献   
53.
First examples of multichain (polycatenar) compounds, based on the π-conjugated [1]benzothieno[3,2-b]benzothiophene unit are designed, synthesized, and their soft self-assembly and charge carrier mobility are investigated. These compounds, terminated by the new fan-shaped 2-brominated 3,4,5-trialkoxybenzoate moiety, form bicontinuous cubic liquid crystalline (LC) phases with helical network structure over extremely wide temperature ranges (>200 K), including ambient temperature. Compounds with short chains show an achiral cubic phase with the double network, which upon increasing the chain length, is at first replaced by a tetragonal 3D phase and then by a mirror symmetry is broken triple network cubic phase. In the networks, the capability of bypassing defects provides enhanced charge carrier mobility compared to imperfectly aligned columnar phases, and the charge transportation is non-dispersive, as only rarely observed for LC materials. At the transition to a semicrystalline helical network phase, the conductivity is further enhanced by almost one order of magnitude. In addition, a mirror symmetry broken isotropic liquid phase is formed beside the 3D phases, which upon chain elongation is removed and replaced by a hexagonal columnar LC phase.  相似文献   
54.
55.
Kwon  Soonho  Choi  Yongtae  Moon  Sangmi  You  Cheolwoo  Liu  Huaping  Kim  Jeong-Ho  Kim  Dae Jin  Park  Hosung  Kim  Jin Young  Hwang  Intae 《Wireless Personal Communications》2020,114(3):2551-2568
Wireless Personal Communications - Wireless solar blind ultraviolet (UV) scattering communication is a new type of atmosphere optics communication technology with the important and potential...  相似文献   
56.
Kwon  Soonho  Kim  Daeoh  Lee  Jihye  Moon  Sangmi  Chu  Myeonghun  Bae  Sara  You  Cheolwoo  Liu  Huaping  Kim  Jeong-Ho  Kim  Dae Jin  Park  Hosung  Kim  Jin Young  Kim  Cheol-Sung  Hwang  Intae 《Wireless Personal Communications》2018,102(1):507-526
Wireless Personal Communications - Generally, a ground telemetry station for a launch vehicle (LV) includes a tracking function only; therefore, position measurements for LV depend on received...  相似文献   
57.
This paper presents a simple process to integrate thin‐film inductors with a bottom NiFe magnetic core. NiFe thin films with a thickness of 2 to 3 μm were deposited by sputtering. A polyimide buffer layer and shadow mask were used to relax the stress of the NiFe films. The fabricated double spiral thin‐film inductor showed an inductance of 0.49 μH and a Q factor of 4.8 at 8 MHz. The DC‐DC converter with the monolithically integrated thin‐film inductor showed comparable performances to those with sandwiched magnetic layers. We simplified the integration process by eliminating the planarization process for the top magnetic core. The efficiency of the DC‐DC converter with the monolithic thin‐film inductor was 72% when the input voltage and output voltage were 3.5 V and 6 V, respectively, at an operating frequency of 8 MHz.  相似文献   
58.
Intermetallic compound (IMC) formation at the interface between the tin (Sn) plating and the copper (Cu) substrate of electronic components has been thought to produce compressive stress in Sn electrodeposits and cause the growth of Sn whiskers. To determine if interfacial IMC is a requirement for whisker growth, bright Sn and a Sn-Cu alloy were electroplated on a tungsten (W) substrate that does not form interfacial IMC with the Sn or Cu. At room temperature, conical Sn hillocks grew on the pure Sn deposits and Sn whiskers grew from the Sn-Cu alloy electrodeposits. These results demonstrate that interfacial IMC is not required for initial whisker growth.  相似文献   
59.
In solution‐based synthesis of colloidal nanostructures, additions of ligands, stabilizers, and redox reagents are generally required to obtain desirable structures, though ligands and stabilizers on the surface of nanostructures can substantially affect the surface‐related activity. Accordingly, an extensive rinsing process is usually required to remove residual reagents and stabilizers. This study reports a spontaneous self‐biomineralization of palladium (Pd) ions on a filamentous virus to form ligand‐free Pd nanowires under ambient conditions. No reducing reagents or additional surface stabilizers are used; the genetically modified virus alone supports the polycrystalline Pd nanowires within the nanostructure, maintaining the clean surface even without a rinsing process. The advantage of the ligand‐free Pd nanowires is found in the Suzuki‐coupling reaction, in which the nanowire catalytic activity is maintained after repeated reactions, while conventional Pd colloids undergo surface contamination by the stabilizer and lose their catalytic activity during repeated uses. The ligand‐free surface, high electronic connectivity, and structural stability of the Pd nanowires also allow high sensitivity and selectivity in hydrogen gas sensing analysis. This work emphasizes the importance of the ligand‐free surface of biotemplated nanostructures in maintaining functionalities without surface contamination.  相似文献   
60.
We investigated the effect of two different quantum well (QW) structures having different indium contents on the optical performance of fully packaged GaN-based light-emitting diodes (LEDs). Dual-spectrum QW LEDs exhibit ~4% higher external quantum efficiency (at 350 mA) than single-spectrum QW LEDs. However, the two types of LEDs exhibit similar efficiency droop behavior. For both types of LEDs, the output power decreases with increasing junction temperature. When the junction temperature exceeds 70°C, the dual-spectrum QW LEDs exhibit lower output power than the single-spectrum QW LEDs. The wavelength dependence of the output power (at 350 mA) of single-spectrum QW LEDs shows that the LEDs with shorter wavelengths experience more rapid optical degradation than the LEDs with longer wavelengths. Based on the wavelength- and junction-temperature-dependent output power, the droop behavior of the dual-spectrum QW LEDs is described and discussed.  相似文献   
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