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Data clustering consists of a group of procedures used to collect similar entries or data points within a set into clusters. No existing clustering technique considers entries sequentially in time. In some cases, it is desirable to generate clusters that represent a segment of a time-ordered data set. For these purposes, an order-specific clustering algorithm is proposed. The proposed algorithm employs representative load curves to describe the clusters it generates. The capabilities of the order-specific clustering algorithm are demonstrated on a case study using electricity demand data for the province of Ontario, Canada. Two different applications of the clustering algorithm on this data set are given to demonstrate the effect of error threshold values on the formation of clusters. An analysis of the error for each of these clustering applications is presented. 相似文献
84.
D. Ballutaud F. Jomard T. Kociniewski E. Rzepka H. Girard S. Saada 《Diamond and Related Materials》2008,17(4-5):451-456
Hot filament and microwave plasma CVD micro- nanocrystalline diamond films are analysed by visible and ultra-violet excitation source Raman spectroscopy. The sample grain size varies from 20 nm to 2 μm. The hydrogen concentration in samples is measured by SIMS and compared to the grain size, and to the ratio of sp2 carbon bonds determined by Raman spectroscopy from the 1332 cm− 1 diamond peak and the sp2 1550 cm− 1 G band. Hydrogen concentration appears to be proportional to the sp2 bonds ratio. The 3000 cm− 1 CHx stretching mode band intensity observed on the Raman spectra is decreasing with the G band intensity. Thermal annealing modifies the sp2 phase structure and concentration, as hydrogen outdiffuses. 相似文献
85.
Y.M. Wong W.P. Kang J.L. Davidson J.H. Huang D.V. Kerns 《Diamond and Related Materials》2008,17(4-5):552-555
A novel integrated vacuum field emission (VFE) differential amplifier (diff-amp) utilizing carbon nanotube (CNT) emitters has been developed. A dual-mask microfabrication process was employed to achieve a VFE diff-amp by integrating identical CNT VFE transistors with built-in split gates and integrated anodes. The identical pair of triode amplifiers was well-matched in their device characteristics. The measured ac small-signal characteristics of the diff-amp showed a common-mode-rejection ratio (CMRR) of ~ 320 (~ 50 dB). The proposed analytical model of the CMRR was verified to be in good agreement with the experimental data. The successful implementation of the CNT diff-amp demonstrates a new way to achieve temperature and radiation tolerant VFE integrated microelectronics. 相似文献
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This paper presents results of a research project, in which a process-dependent real-time control (RTC) strategy for a sequencing batch reactor plant was realised in full-scale. The cycle controller is based on NH4 analysers, NO3 probes, TSS probes and sludge level probes. With this new RTC strategy it was possible to increase the treatment capacity by 50%. By implementation of the new controller the TN, TP and NH4-N treatment efficiency could be improved significantly, too. The treatment efficiency concerning COD is comparable. 相似文献
90.
We present closed-form expressions for the average bit error probability (ABEP) of BPSK, QPSK and M-QAM of an amplify-and-forward average power scaling dual-hop relay transmission, over non-identical Nakagami-m fading channels, with integer values of m. Additionally, we evaluate in closed-form the ABEP under sufficiently large signal-to-noise ratio for the source-relay link, valid for arbitrary rn. Numerical and simulation results show the validity of the proposed mathematical analysis and point out the effect of the two hops unbalanced fading conditions on the error performance. 相似文献