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51.
Mobile Networks and Applications - This study suggests a new product recommendation model to reflect the recent purchasing patterns of customers. There are many methods to measure the similarity...  相似文献   
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53.
In this paper, a profit-aware design metric is proposed to consider the overall merit of a design in terms of power and performance. A statistical design methodology is then developed to improve the economic merit of a design considering frequency binning and product price profile. A low-complexity sensitivity-based gate sizing algorithm is developed to improve economic gain of a design over its initial yield-optimized design. Finally, we present an integrated design methodology for simultaneous sizing and bin boundary determination to enhance profit under an area constraint. Experiments on a set of ISCAS'85 benchmarks show in average 19% improvement in profit for simultaneous sizing and bin boundary determination, considering both leakage power dissipation and delay bounds compared to a design initially optimized for 90% yield at iso-area in 70-nm bulk CMOS technology.  相似文献   
54.
Preventing accidents caused by drowsiness has become a major focus of active safety driving in recent years. It requires an optimal technique to continuously detect drivers' cognitive state related to abilities in perception, recognition, and vehicle control in (near-) real-time. The major challenges in developing such a system include: 1) the lack of significant index for detecting drowsiness and 2) complicated and pervasive noise interferences in a realistic and dynamic driving environment. In this paper, we develop a drowsiness-estimation system based on electroencephalogram (EEG) by combining independent component analysis (ICA), power-spectrum analysis, correlation evaluations, and linear regression model to estimate a driver's cognitive state when he/she drives a car in a virtual reality (VR)-based dynamic simulator. The driving error is defined as deviations between the center of the vehicle and the center of the cruising lane in the lane-keeping driving task. Experimental results demonstrate the feasibility of quantitatively estimating drowsiness level using ICA-based multistream EEG spectra. The proposed ICA-based method applied to power spectrum of ICA components can successfully (1) remove most of EEG artifacts, (2) suggest an optimal montage to place EEG electrodes, and estimate the driver's drowsiness fluctuation indexed by the driving performance measure. Finally, we present a benchmark study in which the accuracy of ICA-component-based alertness estimates compares favorably to scalp-EEG based.  相似文献   
55.
In this letter, a Balun-bandpass filter (BPF) is proposed by using a dual-mode ring resonator. The Balun-BPF is not a simply combined or integrated component of a BPF and a Balun but a single BPF with the balun function. We obtained the proper balanced outputs and two-pole BPF characteristic by symmetrically placing the output ports at lambda/2 distance from each other on the dual-mode ring resonator. The fabricated Balun-BPF has a bandwidth of 40 MHz and an insertion loss of 2.4 dB at a center frequency of 2.45 GHz. The differences between the two outputs are 180-184deg in phase and within 1dB in magnitude. The measured frequency responses agree well with simulated ones.  相似文献   
56.
TixSi1xOy (TSO) thin films are fabricated using plasma‐enhanced atomic layer deposition. The Ti content in the TSO films is controlled by adjusting the sub‐cycle ratio of TiO2 and SiO2. The refractive indices of SiO2 and TiO2 are 1.4 and 2.4, respectively. Hence, tailoring of the refractivity indices from 1.4 to 2.4 is feasible. The controllability of the refractive index and film thickness enables application of an antireflection coating layer to TSO films for use as a thin film solar cell. The TSO coating layer on an Si wafer dramatically reduces reflectivity compared to a bare Si wafer. In the measurement of the current‐voltage characteristics, a nonlinear coefficient of 13.6 is obtained in the TSO films.  相似文献   
57.
The distributions of electric field and induced second‐order nonlinearity are analyzed in the periodic poling of optical fibers. A quasi‐phase matching efficiency for the induced nonlinearity is calculated in terms of both the electrode separation distance between the applied voltage and generalized electrode width for the periodic poling. Our analysis of the quasi‐phase matching efficiency implies that the conversion efficiency can be enhanced through adjusting the separation distance, and the electrode width can be maximized if the electrode width is optimized.  相似文献   
58.
Process integration of cell capacitors that can circumvent the usual difficulties of large topographic height difference and high-temperature process are presented. A 16 Mbit silicon-on-insulator (SOI) DRAM with a 0.3 μm design rule is successfully fabricated and analyzed for processing integrity and circuit performance based on process integration of the cell capacitor using the pattern-bonded SOI (PBSOI) technology. Measurements for the strobe access time (tRAC) acid the operation current (Iccl) show significant improvement (over 25%) for the SOI DRAM compared to those for the 16 Mbit bulk counterpart with the same circuit and layout. On the transistor side, ultra-low-voltage transistor technology using the body bias control schemes is also implemented and investigated. Devices with small leakage current and almost ideal subthreshold swing are obtained. The results give us guidance for transistor and process schematics for low-voltage DRAM application  相似文献   
59.
Subband-based blind signal separation for noisy speech recognition   总被引:1,自引:0,他引:1  
A method for directly extracting clean speech features from noisy speech is proposed. This process is based on independent component analysis (ICA) and a new feature analysis technique for reducing the computational complexity of the frequency domain ICA. For noisy speech signals recorded in real environments, this method yielded a considerable performance improvement  相似文献   
60.
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