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31.
A low-complexity and high performance SCEE (Syndrome Check Error Estimation) decoding method for convolutional codes and its concatenated SCEE/RS (Reed–Solomon) coding scheme are proposed. First, we describe the operation of the decoding steps in the proposed algorithm. Then deterministic values on the decoding operation are derived when some combination of predecoder-reencoder is used. Computer simulation results show that the computational complexity of the proposed SCEE decoder is significantly reduced compared to that of conventional Viterbi decoder without degradation of the Pe performance. Also, simulation results of BER performance of the concatenated SCEE/Hard Decision Viterbi (HD-Viterbi) and SCEE/RS (Reed–Solomon) codes are presented.  相似文献   
32.
Graphene has been highlighted as a platform material in transparent electronics and optoelectronics, including flexible and stretchable ones, due to its unique properties such as optical transparency, mechanical softness, ultrathin thickness, and high carrier mobility. Despite huge research efforts for graphene‐based electronic/optoelectronic devices, there are remaining challenges in terms of their seamless integration, such as the high‐quality contact formation, precise alignment of micrometer‐scale patterns, and control of interfacial‐adhesion/local‐resistance. Here, a thermally controlled transfer printing technique that allows multiple patterned‐graphene transfers at desired locations is presented. Using the thermal‐expansion mismatch between the viscoelastic sacrificial layer and the elastic stamp, a “heating and cooling” process precisely positions patterned graphene layers on various substrates, including graphene prepatterns, hydrophilic surfaces, and superhydrophobic surfaces, with high transfer yields. A detailed theoretical analysis of underlying physics/mechanics of this approach is also described. The proposed transfer printing successfully integrates graphene‐based stretchable sensors, actuators, light‐emitting diodes, and other electronics in one platform, paving the way toward transparent and wearable multifunctional electronic systems.  相似文献   
33.
We report a systematic study of novel single- and double-layer thermosetting light-emitting devices (LED's) based on triarytamines for hole transport layer and fluorenes for the emitting and electron transport layer. These devices possess high-thermal stability, high-quantum efficiency, and high-bandgap emission (blue and green). We have fabricated dot matrix displays based on analogs of these materials  相似文献   
34.
Some interesting electrophysicochemical characteristics of waterpen point-to-plate discharges with DC and AC power have been investigated in a room atmosphere. The metal point electrode of a conventional point-to-plate air gap is severely bombarded by energetic ions from the discharge region near the point. Concurrently, the temperature of the point is greatly increased. There are different characteristics for the waterpen point discharge, because the surface temperature of the waterpen point stays low due to the evaporation of the moisture from the waterpen point. In this paper, the discharges and electrophysicochemical characteristics of a waterpen point and a Pt metal point have been studied to evaluate the differences. It was found that mists and sprays are dispersed from the waterpen point due to the bombardment of ions. Also, a positive corona is effective for mist dispersion, a negative corona disperses sprays, and AC corona disperses both mists and sprays. The AC discharge of the waterpen point generated more ozone of 56 ppm, while it was the negative DC discharge of the Pt point that produced more ozone of 30 ppm. The AC discharge of the waterpen point produced 0.11 ppm at 10 kV, and the Pt point produced 0.10 ppm at 15 kV. The DC discharge of the both points showed no NO formation  相似文献   
35.
A new combined buck and boost push-pull quantum series resonant rectifier (PPQSRR) is proposed to achieve a power factor correction without start-up inrush current. With the proposed control method and circuitry, a high power factor and wide range of output voltage without an inrush current can be obtained  相似文献   
36.
A surface diffusion mocel with diffusional interference has been presented for the analysis of multicomponent adsorption of phenols by activated carbon. Surface diffusion coefficients for multicomponent adsorptions were estimated from the relationship between. the surface diffusion coefficient of each species and the surface coverage. The diffusional interference coefficients, Wij, was determined from experimental counter-adsorption data. The numerical values of Wij were in the range of 0.4–0.9, which show that the introduction of diffusional interference is necessary to analyze multicomponent counter-adsorptions properly. The proposed model successfully simulates the behaviour of phenols-activated carbon system in a batch adsorber.  相似文献   
37.
A new characterization procedure for aqueous solutions with unknown composition was proposed based on the binomial distribution of TOC (total organic carbon) fraction in terms of a characterizing variable, the Freundlich coefficient, k, so that the solution in question can be described by a finite number of pseudo.species identified with a certain k value. The validity and computational accuracy of this procedure has been demonstrated by characterizing three sets of experimental data chosen from different sources. Predictions based on this procedure yielded acceptable results that agreed closely with experimental data.  相似文献   
38.
A printed compact dipole antenna for dual ISM band (2.44 and 5 GHz) is presented. The proposed antenna fed by using a 50 /spl Omega/ coaxial line occupies a volume of 15/spl times/40/spl times/1 mm/sup 3/ (FR-4, permittivity 4.6). The impedance bandwidth for 10 dB return loss is about 400 MHz (from 2170 to 2570 MHz) at 2.4 GHz band and over 2300 MHz (from 4690 to beyond 7000 MHz) at 5 GHz band. The measured radiation gains range from 1.20 to 1.41 dBi at 2.4 GHz band and from 2.25 to 3.44 dBi at 5 GHz band, respectively.  相似文献   
39.
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   
40.
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   
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