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941.
Seok-Woo Lee Eugene Kim Sang-Soo Han Hye Sun Lee Duk-Chul Yun Kyoung Moon Lim Myoung-Su Yang Chang-Dong Kim 《Electron Device Letters, IEEE》2003,24(3):174-176
We have investigated the electrical characteristics of gate oxide films deposited by plasma enhanced chemical vapor deposition (PECVD) with respect to gate oxide integrity (GOI) and its reliability. In the investigation, post-annealed gate oxide was compared with as-deposited oxide. It was shown that the characteristics of GOI strongly depended on the charge trapping characteristics and deep level interface states generation under FN stress, which was remarkably improved by post-annealing after gate oxide deposition. Improved FN stress and hot carrier stress reliability of CMOS devices implemented on the glass substrate are also discussed. 相似文献
942.
Lim C. Nirmalathas A. Attygalle M. Novak D. Waterhouse R. 《Lightwave Technology, Journal of》2003,21(10):2203-2210
We present an optical modulation and distribution scheme that incorporates subcarrier-multiplexed (SCM) transport with remote local oscillator (LO) delivery for a millimeter-wave (mm-wave) fiber-radio backbone driving a sectorized antenna interface. The proposed method is compatible with a standard wavelength-division multiplexing infrastructure with a 25-GHz channel spacing. We also characterize the profiles and bandwidths of the optical filters, which are essential for the adding and dropping of the 25-GHz signal block and the optical extraction of the LO signal. The placement of the LO signal within the 25-GHz band is investigated and its effect on the filter bandwidth requirements and system performance quantified. The performance of a ring incorporating the distribution scheme is evaluated via simulation. It is established that a compromise must be made between the feasibility of the required filters and the incurred penalty due to intermodulation distortions from adjacent blocks. 相似文献
943.
Jin Tae Kim Suntak Park Jung Jin Ju Seung Koo Park Min-Su Kim Myung-Hyun Lee 《Photonics Technology Letters, IEEE》2007,19(18):1374-1376
To improve the propagation loss of polymer-based long-range surface-plasmon-polariton (LR-SPP) waveguide devices at the telecom wavelength range, low-loss LR-SPP waveguides were fabricated in an ultraviolet-curable acrylate polymer with a low refractive index and absorption loss. A propagation loss of 1.72 dB/cm at a wavelength of 1.55 mum was achieved with a 14-nm-thick and 3-mum-wide metal stripe. 相似文献
944.
With the increasing emphasis on supply chain vulnerabilities, effective mathematical tools for analyzing and understanding appropriate supply chain risk management are now attracting much attention. This paper presents a stochastic model of the multi-stage global supply chain network problem, incorporating a set of related risks, namely, supply, demand, exchange, and disruption. We provide a new solution methodology using the Moreau–Yosida regularization, and design an algorithm for treating the multi-stage global supply chain network problem with profit maximization and risk minimization objectives. 相似文献
945.
S.-S. Bae D.K. Lim J.-I. Park J. Cheon I.C. Jeon S. Kim 《Applied Physics A: Materials Science & Processing》2005,80(6):1305-1310
We present a new strategy to fabricate a monolayer assembly of Br-terminated Co nanoparticles on functionalized Si surfaces by using chemical covalent bonding and microcontact printing method. Self-assembled monolayers (SAMs) of the Co nanoparticles formed on the hydroxyl-terminated Si surface exhibit two-dimensional island networks with locally ordered arrays via covalent linkage between nanoparticles and surface. On the other hand, SAMs of the nanoparticles on the aminopropyl-terminated Si surface show an individual and random distribution over an entire surface. Furthermore, we have fabricated striped architectures of Co nanoparticles using a combination of microcontact printing and covalent linkage. Microcontact printing of octadecyltrichlorosilane and selective covalent linkage between nanoparticles and functionalized Si surfaces lead to a hybrid nanostructure with selectively assembled nanoparticles stripes on the patterned functionalized Si surfaces. PACS 81.07.Ta; 61.46.+w; 81.16.Dn; 81.16.Be; 68.37.Hk; 82.80.Pv 相似文献
946.
Adaptive image denoising using scale and space consistency 总被引:8,自引:0,他引:8
This paper proposes a new method for image denoising with edge preservation, based on image multiresolution decomposition by a redundant wavelet transform. In our approach, edges are implicitly located and preserved in the wavelet domain, whilst image noise is filtered out. At each resolution level, the image edges are estimated by gradient magnitudes (obtained from the wavelet coefficients), which are modeled probabilistically, and a shrinkage function is assembled based on the model obtained. Joint use of space and scale consistency is applied for better preservation of edges. The shrinkage functions are combined to preserve edges that appear simultaneously at several resolutions, and geometric constraints are applied to preserve edges that are not isolated. The proposed technique produces a filtered version of the original image, where homogeneous regions appear separated by well-defined edges. Possible applications include image presegmentation, and image denoising. 相似文献
947.
This paper proposes two kinds of complexity‐reduced algorithms for a low density parity check(LDPC) decoder. First, sequential decoding using a partial group is proposed. It has the same hardware complexity and requires a fewer number of iterations with little performance loss. The amount of performance loss can be determined by the designer, based on a tradeoff with the desired reduction in complexity. Second, an early detection method for reducing the computational complexity is proposed. Using a confidence criterion, some bit nodes and check node edges are detected early on during decoding. Once the edges are detected, no further iteration is required; thus early detection reduces the computational complexity. 相似文献
948.
A study on the effect of alkaline earth metal oxide on the activity and stability of nickel catalyst for carbon dioxide reforming
of methane was performed. When CaO, SrO, and BaO were used as supports, there was no difference in catalytic activity between
the catalysts made by coprecipitation and impregnation. However, when MgO was used as a support, the catalyst prepared by
coprecipitation showed superior activity than that made by impregnation. The higher activity of the catalyst made by coprecipitation
was due to the formation of solid solution consisting of nickel and magnesium. The formation of the solid solution enhanced
the dispersion of nickel and the resistance to coke formation. 相似文献
949.
Benaissa M. Wei Ming Lim 《Very Large Scale Integration (VLSI) Systems, IEEE Transactions on》2006,14(6):659-662
The design of flexible elliptic curve cryptography processors (ECP) is considered in this paper. Novel word-level algorithms and implementations for the underlying GF(2/sup m/) multiplication and squaring arithmetic which enable improved flexibility versus performance tradeoffs, are presented and employed in the design of an efficient flexible ECP architecture; corresponding field-programmable gate-array (FPGA) prototyping results for two different processor word lengths are also included for evaluation. 相似文献
950.
Duchang Heo Il Ki Han Jung Il Lee Jichai Jeong 《Photonics Technology Letters, IEEE》2004,16(8):1801-1803
We studied symmetric and asymmetric InGaAsP-InGaAs 1.55-/spl mu/m multiquantum-well (MQW) laser diodes (LDs) with highly p-doped layers in the two-step separate confinement heterostructure (SCH). The p-doping in p-SCH suppresses the electron overflow from the MQWs to p-SCH, but it is an origin of free carrier absorption loss. An additional InGaAsP layer inserted inside n-SCH makes asymmetric field distribution and, therefore, reduces the portion of optical field distribution in highly p-doped regions with high optical loss. Compared with symmetric structure, asymmetric SCH LD has low threshold current density, low internal loss, and high and flat slope efficiency with respect to temperature. 相似文献