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journal of Innovative Optical Health sciences 2013年第4期6卷 33-41页

作者： MEHDI AMIAN s.KAMALEDINsETAREHDAN Control and Intelligent Processing Centre of Excellence school of Electrical and Computer Engineering College of Engineering University of TehranTehranIran

Functional near infrared spectrosecopy(NIRs)is a technique that is used for noninvasive measurement of the oxyhemoglobin(HbO_(2))and deoxyhemoglobin(HHb)concentrations in the brain *** the ratio of the concentration of these two agents is correlated with the neuronal activity,ONIRs can be usod for the monitoring and quantifying the cortical *** portability of NIRs makes it a good candidate for studies involving subject's *** NIRs measurements,however,are sensitive to artifacts generated by subject's head *** makes fNIRs signals less effective in such *** this paper,the autoregressive moving average(ARMA)modeling of the NIRs signal is proposed for state-space representation of the signal which is then fed to the Kalman filter for estimating the motionless signal from motion corrupted *** are compared to the autoregressive model(AR)based approach,which has been done previously,and show that the ARMA models outperform AR *** attribute it to the richer structure,containing more terms indeed,of ARMA than *** show that the signal to noise ratio(sNR)is about 2 dB higher for ARMA based method.

关键词： Brain Gaussian noise linear model state estimation

Bryozoan Nodules as a Frame-Builder of BryozoanMicroreef, Middle Miocene sediments, Egypt

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journal of Earth science 2015年第2期26卷 251-258页

作者： Abdelbaset s.El-sorogy Geology and Geophysics Department College of Science King Saud University Geology Department Faculty of Science Zagazig University

Bryozoan nodules, coralline algae, scleractinian corals and oysters form an important organic buildup, 1.2-4.5 m thick in the Langhian-serravaliann sediments of Egypt. Based on type, shape and size of the substrate, bryozoan nodules take tree-like and globular morphologies. Tree-like speci- mens reach 10 cm in maximum height and 3 cm in diameter, while Globular ones attain 9 cm in maxi- mum diameter. Most tree-like nodules are perforated with wide or narrow pores, few are non-perforated. Globulars and few tree-like forms are with mamelon-like structures. Perforations on the outer surfaces may indicate a symbiotic relationship between bryozoans and a live plant substrate. Nod- ules from Homiera and Gharra areas of the Cairo-suez District with wider perforations may indicate growth in slightly lighter or turbid areas of the continental shelf than those of North Western Desert of narrower perforations. Non-perforated nodules may assume an incrustation on ephemeral substrate .

关键词： Miocene bryozoa frame builder microreef paleoecology Egypt.

Automatic Delineation of Lung Parenchyma Based on Multilevel Thresholding and Gaussian Mixture Modelling

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Computer Modeling in Engineering & sciences 2018年第2期114卷 141-152页

作者： s.Gopalakrishnan A.Kandaswamy Department of Biomedical Engineering PSG College of TechnologyCoimbatoreTamil NaduIndia

Delineation of the lung parenchyma in the thoracic Computed Tomography(CT)is an important processing step for most of the pulmonary image analysis such as lung volume extraction,lung nodule detection and pulmonary vessel *** automatic method for accurate delineation of lung parenchyma in thoracic Computed Tomography images is presented in this *** proposed method involves a segmentation phase followed by a lung boundary correction *** tissues in the thoracic Computed Tomography can be represented by a number of *** propose a histogram utilized Adaptive Multilevel Thresholding(AMT)for estimating the total number of Gaussians and their initial *** parameters of Gaussian components are updated by Expectation Maximization(EM)*** segmented lung parenchyma from the Gaussian Mixture model(GMM)undergoes an Adaptive Morphological Filtering(AMF)to reduce the boundary *** proposed method has been tested on 70 diseased and 119 normal lung images from 28 cases obtained from Lung Image Database Consortium(LIDC).The performance of the proposed system has been validated.

关键词： Lung parenchyma delineation thoracic computed tomography multilevel thresholding Gaussian mixture model Adaptive Morphological Filtering

Abundant closed-form wave solutions to the simplified modified Camassa-Holm equation

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journal of Ocean Engineering and science 2023年第3期8卷 238-245页

作者： s M Rayhanul Islam s M Yiasir Arafat Hanfeng Wang school of Civil Engineering Central South UniversityChangshaHunan 410075China Department of Mathematics Pabna University of Science and TechnologyPabna 6600Bangladesh

The simplified modified Camassa-Holm (sMCH) equation is an important nonlinear model equation for identifying various wave phenomena in ocean engineering and science. The new auxiliary equation (NAE) method has been applied to the sMCH equation. Base on the method, we have obtained some novel an- alytical solutions such as hyperbolic, trigonometric, exponential, and rational function solutions of the sMCH equation. For appropriate values of parameters, three dimensional (3D) and two dimensional (2D) graphs are designed by Mathematica. The stability of the model is also discussed in this manuscript. The dynamic and physical behaviors of the solutions derived from the sMCH equation have been ex- tensively discussed by these plots. All our solutions are indispensable for understanding the nonlinear phenomena of dispersive waves that are important in ocean engineering and science. In addition, our results are essential to clarify the various oceanographic applications containing ocean gravity waves, offshore rig in water, energy associated with a moving ocean wave and numerous other related phenom- ena. Finally, the obtained solutions are helpful for studying wave interactions in many new structures and high-dimensional models.

关键词： sMCH equation NAE method Nonlinear physics Kink shape solitary wave

VARIABLE sTEP-sIZE IMPLICIT-EXPLICIT LINEAR MULTIsTEP METHODs FOR TIME-DEPENDENT PARTIAL DIFFERENTIAL EQUATIONs

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journal of Computational Mathematics 2008年第6期26卷 838-855页

作者： DongWang steven j. Ruuth Department of Civil and Environmental Engineering University of Illinois at Urbana-Champaign B231 Newmark Civil Engineering Laboratory Urbana IL 61801 USA Department of Mathematics Simon Fraser University Burnaby BC Canada V5A 1S6

Implicit-explicit （IMEX） linear multistep methods are popular techniques for solving partial differential equations （PDEs） with terms of different types. While fixed timestep versions of such schemes have been developed and studied, implicit-explicit schemes also naturally arise in general situations where the temporal smoothness of the solution changes. In this paper we consider easily implementable variable step-size implicit-explicit （VsIMEX） linear multistep methods for time-dependent PDEs. Families of order-p, pstep VsIMEX schemes are constructed and analyzed, where p ranges from 1 to 4. The corresponding schemes are simple to implement and have the property that they reduce to the classical IMEX schemes whenever constant time step-sizes are imposed. The methods are validated on the Burgers＇ equation. These results demonstrate that by varying the time step-size, VsIMEX methods can outperform their fixed time step counterparts while still maintaining good numerical behavior.

关键词： Implicit-explicit (IMEX) linear multistep methods Variable step-size Zero-stability Burgers' equation.

Preparation of Ga_2O_3 thin film solar-blind photodetectors based on mixed-phase structure by pulsed laser deposition

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Chinese Physics B 2019年第1期28卷 171-177页

作者： Y M Lu C Li X H Chen s Han P j Cao F jia Y X Zeng X K Liu W Y Xu W j Liu D L Zhu College of Materials science and Engineering Shenzhen Key Laboratory of Special Functional MaterialsShenzhen Engineering Laboratory for Advanced Technology of CeramicsGuangdong Research Center for Interfacial Engineering of Functional MaterialsShenzhen UniversityShenzhen 518060China

Gallium oxide(Ga_2O_3) thin films were deposited on a-Al2O3(1120) substrates by pulsed laser deposition(PLD) with different oxygen pressures at 650?C. By reducing the oxygen pressure, mixed-phase Ga_2O_3 films with α and β phases can be obtained, and on the basis of this, mixed-phase Ga_2O_3 thin film solar-blind photodetectors(sBPDs) were *** the responsivities of the mixed-phase Ga_2O_3 sBPDs and the single β-Ga_2O_3 sBPDs at a bias voltage of 25 V,it is found that the former has a maximum responsivity of approximately 12 A/W, which is approximately two orders of magnitude larger than that of the latter. This result shows that the mixed-phase structure of Ga_2O_3 thin films can be used to prepare high-responsivity sBPDs. Moreover, the cause of this phenomenon was investigated, which will provide a feasible way to improve the responsivity of Ga_2O_3 thin film sBPDs.

关键词： Ga2O3 mixed-phase solar-blind photodetector pulsed laser deposition

Arc erosion of AgsnO_2 electrical contacts at different stages of a break operation

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Rare Metals 2010年第3期29卷 248-254页

作者： j. swingler A. sumption school of Engineering sciences University of Southampton

Arc erosion studies are conducted on AgsnO2 contact materials at different stages in the break operation. A resistive load arrangement is used with up to 42 V DC at 24 A and a constant contact opening velocity. The arc current is terminated at different stages as the arc is drawn between the contacts enabling a study of the arcing phenomena up to that point. surface profiling of the contacts is conducted to determine the extent of erosion at the different stages as the arc is drawn. spectral analysis is also conducted on the arc and then related to the extent of erosion. The results show that particular features occur at different stages as the arc is drawn. As the arc is initially established, it goes through an ＂Arc Generation＂ regime where the arc roots are small and immobile on both the anode and the cathode. Material transfer occurs mainly from anode to cathode. The spectral analysis indicates that sn and O species dominate the arc followed by the Ag species. As the arc is drawn further and enters the ＂Arc Degeneration＂ regime, the anode undergoes significantly larger erosion than the cathode. Also, both contacts indicate that multiple arc roots have formed, which are highly mobile in the later stages of the discharge. The spectral analysis indicates that Ag and N species are in high concentrations compared to other species. The mechanisms of erosion and deposition are discussed in relation to the species within the arc discharge. For the complete break operation, it is found that the anode undergoes major erosion, and it is thought that the gaseous ions species do not dominate the arc under these conditions of short arcs and voltage 〈42 V to cause cathode erosion.

关键词： contact materials electrical contacts arc erosion 3D surface profiles spectral analysis

surface morphology and impurity distribution of electron beam recrystallized silicon films on low cost substrates for solar cell absorber

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Rare Metals 2006年第Z1期25卷 195-200页

作者： GROMBALL F MüLLER j Department of Mikrosystemtechnik Technische Universitt Hamburg-Harburg Hamburg 21073 Germany

A line shaped electron beam recrystallised polycrystalline silicon film on the low cost substrate was investigated for the use of the solar cell absorber. The applied EB energy density strongly influences the surface morphology of the film system. Lower EB energy density results in droplet morphology and the rougher siO2 capping layer due to the low fluidity. With the energy increasing, the capping layer becomes smooth and continuous and less and small pinholes form in the silicon film. Tungstendisilicide (Wsi2) is formed at the interface tungsten/silicon but also at the grain boundaries of the silicon. Because of the fast melting and cooling of the silicon film, the eutectic of silicon and tungstendisilicide mainly forms at the grain boundary of the primary silicon dendrites. The sEM-EDX analysis shows that there are no chlorine and hydrogen in the area surrounding a pinhole after recrystallization because of outgassing during the solidification.

关键词： polycrystalline silicon film solar cell recrystallization energy surface morphology outgassing

Alumina Effect on the Phase Transformation of 3Y-TZP Ceramics

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journal of Materials science & Technology 2008年第6期24卷 873-877页

作者： Ezzat s.Elshazly M.El-sayed Ali s.M.El-Hout Department of Metallurgy Nuclear Research CenterAtomic Energy AuthorityCairoEgypt

The isothermal tetragonal-to-monoclinic phase transformation of 3 mol fraction Y2O3-ZrO2 ceramics contain- ing different amounts of Al2O3 during ageing in water at 130℃ for periods of time up to 40 h was investigated to explore the effect of Al2O3 addition on this transformation. The propagation of the transformation into the specimen interiors was suppressed by the addition of Al2O3. The transformation kinetics showed a nucleation and growth mechanism on the specimen surface to be dominant in the low temperature ageing in water environment.

关键词： Phase transformation 3Y-TZP Al2O3 Kinetics

Energy Proficient Reliable Rim Routing Technique for Wireless Heterogeneous sensor Networks Lifespan Fortification

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Circuits and systems 2016年第8期7卷 1751-1759页

作者： s. G. susila j. Arputhavijayaselvi VF/ECE Anna University Chennai BIT Campus Tiruchirappalli India Dean R and D Professor/ECE Kings College of Engineering Pudukottai India

sensor nodes are mainly shielded in the field with limited power supply. In Wireless sensor Networks, there must be a requirement of an efficient power management, because sensor nodes are deployed in unman attended area with non-rechargeable batteries. Power management can be done by different methods of routing protocols. The proposed Reliable Rim Routing (3R) technique is based on hybrid routing protocol for homogeneous and heterogeneous system for WsNs to ameliorate the performance of the overall system. In 3R, total node deployment area can be multipart in terms of rim and in each rim, and some of the sensor nodes transmit their sensed data directly to base station, and meanwhile remaining sensor nodes send the data through clustering technique to base station like sEP. Proposed 3R technique implementation proves its enhanced WsNs lifetime of 70% energy consumption and 40% throughput compared with existing protocols. simulation and evaluation results outperformed in terms of energy consumption with increased throughput and network lifetime.

关键词： Cluster Cluster Head Heterogeneous Rim Layer Node Deployment Technique Wireless sensor Network