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51.
Xin Sun Qiang Lu Moroz V. Takeuchi H. Gebara G. Wetzel J. Shuji Ikeda Changhwan Shin Tsu-Jae King Liu 《Electron Device Letters, IEEE》2008,29(5):491-493
A tri-gate bulk MOSFET design utilizing a low-aspect-ratio channel is proposed to provide an evolutionary pathway for CMOS scaling to the end of the roadmap. 3-D device simulations indicate that this design offers the advantages of a multi-gate FET (reduced variability in performance and improved scalability) together with the advantages of a conventional planar MOSFET (low substrate cost and capability for dynamic threshold-voltage control). 相似文献
52.
镍氢电池负极用低成本储氢合金的研究 总被引:1,自引:0,他引:1
研究了ABS型储氢合金在低Co含量条件下,随B组元替代元素Co,Al,Si等含量的变化对合金电化学性能的影响规律,同时研究了A组元中不同La/Ce比对合金电化学性能的影响情况。结果表明,随合金中Co含量的降低,合金的活化性能和放电容量得以改善,但合金的循环寿命下降也比较明显;在试验范围内,随Al元素的加入,合金的循环寿命得以改善,但材料的放电容量和活化性能均有所下降;随合金La/Ce比的降低,合金的放电容量略有下降,但其循环寿命和放电电压平台有较大提高。 相似文献
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Evolving artificial neural network ensembles 总被引:3,自引:0,他引:3
Using a coordinated group of simple solvers to tackle a complex problem is not an entirely new idea. Its root could be traced back hundreds of years ago when ancient Chinese suggested a team approach to problem solving. For a long time, engineers have used the divide-and-conquer strategy to decompose a complex problem into simpler sub-problems and then solve them by a group of solvers. However, knowing the best way to divide a complex problem into simpler ones relies heavily on the available domain knowledge. It is often a manual process by an experienced engineer. There have been few automatic divide-and-conquer methods reported in the literature. Fortunately, evolutionary computation provides some of the interesting avenues to automatic divide-and-conquer methods. An in-depth study of such methods reveals that there is a deep underlying connection between evolutionary computation and ANN ensembles. Ideas in one area can be usefully transferred into another in producing effective algorithms. For example, using speciation to create and maintain diversity had inspired the development of negative correlation learning for ANN ensembles, and an in-depth study of diversity in ensembles. This paper will review some of the recent work in evolutionary approaches to designing ANN ensembles. 相似文献
55.
Xin Qi Salapaka M.V. Voulgaris P.G. Khammash M. 《Automatic Control, IEEE Transactions on》2004,49(10):1623-1640
In this paper, the design of controllers that incorporate structural and multiobjective performance requirements is considered. The control structures under study cover nested, chained, hierarchical, delayed interaction and communications, and symmetric systems. Such structures are strongly related to several modern-day and future applications including integrated flight propulsion systems, platoons of vehicles, micro-electro-mechanical systems, networked control, control of networks, production lines and chemical processes. It is shown that the system classes presented have the common feature that all stabilizing controllers can be characterized by convex constraints on the Youla-Kucera parameter. Using this feature, a solution to a general optimal performance problem that incorporates time domain and frequency domain constraints is obtained. A synthesis procedure is provided which at every step yields a feasible controller together with a measure of its performance with respect to the optimal. Convergence to the optimal performance is established. An example of a multinode network congestion control problem is provided that illustrates the effectiveness of the developed methodology. 相似文献
56.
Interfacial hybridization kinetics of oligonucleotides immobilized onto fused silica surfaces 总被引:3,自引:0,他引:3
Jiang Zeng Amer Almadidy James Watterson Ulrich J. Krull 《Sensors and actuators. B, Chemical》2003,90(1-3):68-75
Fused silica optical fibers have been used in an intrinsic mode optical configuration as biosensors for fluorescence based detection of hybridization of nucleic acids. In this work, the kinetics of hybridization of single-stranded oligonucleotides that were covalently immobilized were studied. The probe DNA was dT20, and the target was Fluorescein-labeled non-complementary (dT20) or complementary (dA20) oligonucleotide. Chronofluorimetric monitoring of the adsorption and hybridization processes was used to investigate oligonucleotide films of different density, in different salt concentrations, at temperatures of 25 and 40 °C, with the concentration of the target DNA being 0.005–0.1 μM. Mathematical models based on first- and second-order Langmuir adsorption have been examined to describe both the adsorption and the hybridization processes. Experimental data were processed using the models, and the hybridization kinetics were calculated. Hybridization kinetics on these optical fiber DNA sensors was found to be up to three orders faster than results presented for a number of other experiments using different immobilization chemistries. 相似文献
57.
蒋光祖 《上海电机学院学报》2003,6(4):9-10
推导了变压器二次负载电压的计算公式,建议由此公式代替以往原理书中惯用的近似公式。利用此公式绘制和分析了不同功率因数额定负载时的相量轨迹图。 相似文献
58.
59.
Colour is the most widely used attribute in image retrieval and object recognition. A technique known as histogram intersection has been widely studied and is considered to be effective for color‐image indexing. The key issue of this algorithm is the selection of an appropriate color space and optimal quantization of the selected color space. The goal of this article is to measure the model performance in predicting human judgment in similarity measurement for various images, to explore the capability of the model with a wide set of color spaces, and to find the optimal quantization of the selected color spaces. Six color spaces and twelve quantization levels are involved in evaluating the performance of histogram intersection. The categorical judgment and rank order experiments were conducted to measure image similarity. The CIELAB color space was found to perform at least as good as or better than the other color spaces tested, and the ability to predict image similarity increased with the number of bins used in the histograms, for up to 512 bins (8 per channel). With more than 512 bins, further improvement was negligible for the image datasets used in this study. © 2005 Wiley Periodicals, Inc. Col Res Appl, 30, 265–274, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.20122 相似文献
60.