Cabral V.M.,ICE |
Barros L.C.,University of Campinas
2012 Annual Meeting of the North American Fuzzy Information Processing Society, NAFIPS 2012 | Year: 2012
We study the SI epidemiological model in two distinct ways, one considering correlation between the numbers of susceptible and infected individuals, and another assuming that the initial conditions and the transmission rate are interactive. In both cases we assume uncertainties given by fuzzy sets. Interactivity is based on the concept of completely correlated fuzzy numbers. The dynamics of each model is represented by fuzzy differential equations (FDE) approached in two ways: the first using the theory of fuzzy differential inclusion and the second using Zadeh's extension principle to obtain a solution. We found that both produce the same solution. © 2012 IEEE.
Zhang W.T.,ICE |
Li Z.Q.,ICE |
Applied Mechanics and Materials | Year: 2013
Frequency locked loop (FLL) plays an important role in carrier synchronization because of its excellent dynamic performance. However, it performs inadequately in low signal-to-noise ratio (SNR). In this paper, the principle of stochastic resonance (SR) is briefly introduced and a SR processor is proposed. Based on traditional FLL, the SR processor is added before frequency discriminator in order to weaken the effect that thermal noise brings to FLL. The paper investigates the processing effect of SR. Simulation results show that the performance of improved FLL is greatly improved. It can tolerate rather high dynamics and tracking accuracy of frequency achieve 0.2Hz even with CNR as low as 25 dBHz, which verified the validity of above ideas. © 2013 Trans Tech Publications Ltd, Switzerland.
Lei S.,Postgraduate Team 2 |
2011 International Conference on Wireless Communications and Signal Processing, WCSP 2011 | Year: 2011
In this paper, the narrowband DOA estimation problem is studied in compressive sensing (CS) perspective. A novel DOA estimation approach based on extended Bayesian compressive sensing (BCS) is presented. To avoid the matrix singular drawback in BCS, a basis pruning procedure through iterative hard thresholding is utilized. The proposed method is hyper-parameter free and needs not know the number of sources a prior. Simulation results demonstrate that the proposed scheme has high space resolution and can resolve highly correlated or coherent sources. © 2011 IEEE.
Kumar P.,ICE |
Singh S.K.,Krishna Institute of Engineering and Technology |
Ojha P.,Krishna Institute of Engineering and Technology
Proceedings - 2011 International Conference on Computational Intelligence and Communication Systems, CICN 2011 | Year: 2011
Analyze some of the basic principles involved in the design of optical fiber based displacement sensor and to apply it to design a weight measurement system. Bifurcated optical fiber sensors can have many applications. Having high sensitivity to short distances, bifurcated optical fiber (Y-sensor) is well suited not only for control applications as position sensors, but also for gauging and surface assessment. In addition, they can be utilized as non contact pressure sensors if used in conjunction with reflective diaphragms moving in response to pressure. Y-sensor can also be applied as temperature transducer if used in conjunction with deformable bimetal sensors. © 2011 IEEE.
Semmling A.M.,Helmholtz Center Potsdam |
Beyerle G.,Helmholtz Center Potsdam |
Stosius R.,Helmholtz Center Potsdam |
Dick G.,Helmholtz Center Potsdam |
And 8 more authors.
Geophysical Research Letters | Year: 2011
This paper evaluates the usage of reflected GPS signals for Earth observations to study changes of sea level and sea-ice in remote sensing. In a coastal setup, ∼670 m above Disko Bay (Greenland), signals with different carriers L1 and L2 were recorded. A method is presented that analyses the interferometric phase between the reflected and the direct signals and derives the height of the reflecting surface. The analysis includes a ray tracing and an estimation of signal coherence. It is shown that coherent reflections are related to sea-ice coverage. Absolute heights are derived with a time interval of ∼30 min. The altimetric results show semidiurnal tides that are validated using the AODTM-5 tide model. The residual height has a mean of 9.7 cm for L1 and 22.9 cm for L2. The dispersion is not significant but a significant tropospheric bias is detected with an error of up to 20 cm. Copyright © 2011 by the American Geophysical Union.
Abreu V.G.C.,University of Sao Paulo |
da Silva M.C.,University of Sao Paulo |
Magalhaes R.M.,University of Sao Paulo |
Pilo-Veloso D.,University of Sao Paulo |
And 3 more authors.
Acta Amazonica | Year: 2010
Three coumarins, 5-methoxypsoralene, xanthyletin, and (-)-marmesin, have been isolated from the ethanolic extract of the stem of the Amazonian plant Brosimum potabile. The structures were determined on the basis of NMR analyses and by comparison with spectroscopic data in the literature. The analysis of the hexane fractions by GC-MS in EIMS mode suggested the presence of (1-methylpentyl)-benzene; α,α-dimethyl-4-(1-methylethyl)-benzenemethanol; 1-methyl-3,5-bis(1-methylethyl)- benzene; urs-12-ene; chola-5,22-dien-3β-ol; cholesta-4,6-dien-3β-ol; sitosteryl 9(Z)-octadecenoate; cholesta-5,22-dien-3β-ol; cholesta-4,6,22-trien-3-one; and cholesta-4,22-dien-3-one. NMR data of other hexane fractions indicated the presence of 3β-acetoxy-lup-12,20(29)-diene; 3β-acetoxy-olean-12-ene; 3β-acetoxy-urs-12-ene; and adian-5-ene. All these compounds are first described in B. potabile.
Cao M.,Xian Communication Institute |
Liu X.,ICE |
International Conference on Communication Technology Proceedings, ICCT | Year: 2010
Noncoherent demodulation is often used in many communication systems in which it is difficult to synchronize the carrier phase. It is generally acknowledged that iterative decoding technique plays an important role in improving performance. But at present, few researches on the iterative noncoherent detection for GMSK signals have been done. This paper proposes a novel noncoherent receiver for GMSK signals based on SCCC structure over an AWGN channel. At the transmitter, GMSK modulator can be made equivalent to a form of special recursive convolutional encoder. Then it is concatenated with the convolutional encoder and interleaver. At the receiver, GMSK modulation is viewed as the inner encoding of SCCC. And it is important to extend the received symbols for decoding the inner GMSK signals. Thus, based on MSDD(multiple symbol differential detectors) structure, the inner decoder implements GMSK noncoherent iterative detection by extending the virtual trellis structure. The simulation results show that this receiver has excellent performance and has ability against certain frequency offset. © 2010 IEEE.
International Journal on Hydropower and Dams | Year: 2012
Soaring international prices for oil and gas are driving the expansion of renewable energies in Central America, a region which has plenty of untapped potential for producing hydropower, wind power and geothermal energy. The seven countries in the region are taking steps to accelerate the use and diversification of the renewable energies. This has created a new climate for business, and an increase in regional investments in and between transboundary nations.
Yang J.,ICE |
Lu C.-L.,ICE |
Hu Y.-J.,ICE |
Jia J.-X.,ICE |
2012 International Conference on Microwave and Millimeter Wave Technology, ICMMT 2012 - Proceedings | Year: 2012
A broad band wide beam circular polarization microstrip antenna is designed and analyzed. The antenna uses double-layer circular patch to broad bandwidth. The antenna is enclosed by a folded conducting wall so that a wide radiation beam is achieved. Parametric studies are performed to explore the performance improvements. The simulated and measured results indicate that the bandwidth of the antenna is 900MHz (from 3.46GHz to 4.36GHz) while the reflection coefficient is less than -13dB and the half-power beamwidth can achieve 120°. In the bandwidth, the antenna is realized with a good gain and a good circular polarization fed by a Wilkinson power divider with 90° phase difference. © 2012 IEEE.
News Article | November 12, 2016
NASHVILLE, Tenn., Nov. 11, 2016 /PRNewswire/ -- With the flip of a switch, Nashville's Gaylord Opryland Resort tonight turned on its 2.3 million holiday lights and officially kicked off its 33rd annual A Country Christmas celebration. A Country Christmas, presented by FUJIFILM INSTAX...