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For a class of chaotic systems with uncertain nonlinear time-delay functions and exogenous disturbance, the problem of observer-based adaptive synchronization is investigated. Based on Lyapunov-Krasovskii fucntional method, a delay-free observer is presented by using sliding mode control and adaptive control techniques. Two numerical simulations are given to show the effectiveness of the proposed...
The problem of adaptive fuzzy fault accommodation for nonlinear coupled complex dynamical networks (CDNs) is studied in our work. A fuzzy logical system (FLS)-based fault accommodation control is provided to achieve the synchronization. Especially, it is proved that the asymptotic convergence of the synchronization errors can be ensured by using a convex combination technique and an important graph...
In this work, by using random access and priority considerations we develop a mobile healthcare network. We assign 4 medical information priorities to the nodes of wireless body area network. Accurate and quick prioritization of personal healthcare information is crucial for making efficient and real-time decisions. We transfer the medical data to the access point in wireless body area network by...
This paper addresses the problem of observer design for a class of uncertain nonlinear time-delay systems. A finite-dimensional adaptive observer is proposed based on Lyapunov-Krasovskii functional method and neural-networks-based approximation technique. The designed observer guarantees that all signals in the closed-loop system are bounded and the estimation error decreases to zero asymptotically...
Intelligent robot operating autonomously in an unknown environment is an important research hotspot in the field of artificial intelligence, in which the smart avoidance technology has been well focused on. To deal with the issue of excessive input/output variables, slow response and “curse of dimensionality” of traditional fuzzy algorithm, a hierarchical fuzzy controller has been designed. The input...
This paper presents the design of a double balanced current-mirror mixer with current reusing technique. The proposed mixer is based on high linearity current mirror structure which guarantees a high IIP3. To improve the power efficiency of the current mirror structure, a current reusing technique is used to share the bias current of the transconductance stage and the output stage. Compared with the...
This paper presented an architecture of IEEE 802.15.4 standard-based MAC controller containing improved CSMA/CA mechanism, hardware security mechanism, efficient frame processing, ACK mechanism etc. The design of MAC controller individual module and detailed structure is completed optimal. Module level of this MAC controller is simulated after the RTL level design, and is verified via FPGA. The hardware...
According to the Montreal Protocol, because of the depletion to the ozone layer of the earth, CFCs was required to be phased out by the international society. While consideration of the specific circumstances of Chinese MDI industry and the progress of CFC phase-out efforts, Chinese government issued the National Transition Strategy for the phase-out of CFCs used in MDI, to swiftly and reasonably...
Electromagnetically induced transparency — Like spectrum with tunable group delay is observed in a periodically poled LiNbO3 with a central defect when an electric field is applied. A low voltage bulk phase shifter is obtained.
In this paper, we present the considerations on miniaturizing the size of the circular disc antennas, which are often used in UWB applications. Quarter circular disc antenna has been proposed to reduce the antenna size to approximately one fourth of the original circular one. Tapered microstrip feed line and hollowed disc designs have been adopted for enhancing the impedance matching. The developed...
Fretting damage behavior of Ni-B and Ni-B-C60 electroless plating deposited on TA7 titanium alloy are studied. The fretting wear resistance of the two coatings is tested and the coating surface morphology is also observed. The results show that the Ni-B-C60 coating has self-lubricated property during the process of fretting wear, indicating lower friction coefficient than that of Ni-B coating. The...
In this paper, a highly robust digital video watermarking technique is given. First of all, the watermark information is encrypted by Arnord transform. Then it is embedded in DCT domain by high-frequency coefficients correlation algorithm in RGB frames of source video file. The field tests indicate that the video file with the watermark information is transparent, and strong anti-aggressive.
Based on the analysis of virtual environment modeling and research on the OpenGL, this paper combines the graphics-based and image-based modeling methods to construct a virtual environment system model. Through a friendly Windows user interface, this system displays users with a realistic three-dimensional virtual environment to meet certain requirements of roaming and interoperability, which has...
Urban wetlands play a significant role in the sustainable development. But the effect of human action on urban wetlands has been expanded in greater scope and depth, which may cause the accelerated degeneration of urban wetlands seriously. Based on the historical data of land using maps, topographic maps and TM images of Wuhan from 1930s to 2005, which were through the Man-Machine Interaction in ArcGIS...
We proposed the coupling and competition of second harmonic generation (SHG) and acousto-optic (AO) interaction in periodically poled lithium niobate (PPLN). The reciprocal vector of PPLN compensates the SHG wave-vector mismatch when quasi-phase-matching (QPM) condition is satisfied, while phonons with suitable frequencies may affect it by scattering photons to different polarization state. Second...
Polarization independent sum frequency generation (SFG) is proposed in an electro-optic (EO) tunable periodically poled Lithium Niobate (PPLN). The PPLN consists of four sections. External electric field could be selectively applied to them to induce polarization rotation between the ordinary and extraordinary waves. If the domain structure is well designed, the signal wave with an arbitrary polarization...
Periodically poled Lithium Niobate (PPLN) is a promising material for wavelength conversion and switching in an all-optical network. However, current PPLN based network elements are normally polarization sensitive, which is not convenient for telecom applications. We proposed a polarization insensitive frequency conversion approach in a PPLN. The second harmonic generation (SHG) studied as an example...
Adopting cement with sand to make intermittent cracked Rock-like samples, this article, through cracked samples with different cracked obliquity is tested with WDT-1500 multifunctional material test apparatus, study the mechanics characteristic and the destruction properties of rock mass, which under the combined action of cyclic load and the static load. Using computer processed the experimental...
A new and rapid scheme for detecting vehicles based on video by single camera at urban intersection is proposed. Firstly a rapid judgment algorithm of vehicle direction is introduced, with motion object segmentation by means of frame-difference method and morphology. It extracts the unique interested region from multiple objective through the modified region-growth algorithm, gets motion direction...
Based on the methods of the others, used the stochastic medium theory, the expressions about main influence angle of stratum are proposed in this paper to validate its rationality especially in hard clay in some factual project. The results show that the expressions can reflect on the ground settlement caused by tunnel construction very well and afford a certain reference to the engineer.
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