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The non-interferometric phase retrieval technique based on the transport-of-intensity equation (TIE) is employed to calculate the missing phase information from the intensity measurement. However, since the limiting effect of the lens aperture is existed in the actual imaging system, a certain effect on the resolution of the recovery phase is under consideration. A phase retrieval technology based...
A 402–405 MHz MICS-band wake-up receiver is presented that achieves −63.8 dBm sensitivity at 4.5 nW. High sensitivity at 400 MHz is accomplished via an 18.5 dB passive voltage gain transformer filter loaded by a high input impedance (Rin > 30 kΩ), high scaling factor (kED > 300), 1.8 nW current re-use pseudo-balun envelope detector, while low power is achieved by operating all active circuits,...
The autonomous parking system is an intelligent system which can park a car into a parking spot. Recently, more and more studies pay attention on this system. However, research on evaluation of autonomous parking system in these studies is not enough. Because most of evaluation methods of intelligent vehicle system are based on task completion degree, the evaluation of autonomous parking system cannot...
Bayesian Compressive Sensing (BCS), introduced into wideband cognitive radio network (CRN), has been considered as a promising technique for its ability of accurately recovering a signal from far fewer samples than required by the Nyquist sampling theorem. However, as BCS algorithm modulates the number of measurements step by step through evaluating the error bars, it needs appreciable amounts of...
The semantic description of remote sensing image is a useful and meaningful task, which can help us to get a better understanding of the scene depicted in the remote sensing images and make better use of the remote sensing images. Nature language provides good solution for describing the semantic information of remote sensing images. Nature language description of a remote sensing image is to generate...
This paper focuses on consensus of multi-agent systems with leader-following and unknown nonlinear dynamics under heterogenous topologies. First of all, we give a control algorithm for the condition that the system without leader under heterogeneous topologies. Sufficient conditions in terms of linear matrix inequality (LMI) are established to guarantee distributed consensus of multi-agent systems...
The importance of carrier-based landing has been a controversial topic. The wave excites the ship to make six-degree-of-freedom motion, accompanied by atmosphere turbulence flow and ship airwake, making the carrier-based aircraft landing a great challenge. Aimed to ensure the safety of carrier-based aircraft and precision landing, a method of the constrained command filtered prescribed performance...
A broadband mode multiplexer/demultiplexer based on two mutually spliced tapered multi-core fiber is proposed in this paper. The bandwidth is larger than 800nm for mode coupling from LP01 mode to LP11 mode and is equivalent to 400nm for mode coupling from LP01 mode to LP21 mode.
Wake-up receivers (WuRXs) are low-power radios that continuously monitor the RF environment to wake up a higher-power radio upon detection of a predetermined RF signature. Prior-art WuRXs have 100s of kHz of bandwidth [1] with low signature-to-wake-up-signal latency to help synchronize communication amongst nominally asynchronous wireless devices. However, applications such as unattended ground sensors...
The inspiration of computer design comes from the human. Learning from human cognitive mechanism, laid the foundation for the development of unmanned driving field in our country. Based on the information processing model of Cognitive Psychology, there are three stages of the manned driving behaviors "stimulus perception, judgment and decision making and stimulus performance", to establish...
Vehicular Ad hoc Networks (VANETs) using wireless multi-hop technology have recently received considerable attention. Because of frequent link disconnection caused by high mobility and signal attenuation due to obstacles (e.g. tall buildings) in urban areas, it becomes quite challenging to disseminate packets to destinations locating in a specified area. We proposed a novel geocast routing protocol...
Genetic algorithm is a kind of way to solve complex problems effectively, for it is not bound by the restrictive assumptions of the search space, and doesn't require the assumption conditions such as continuity and derivatives. So this algorithm has its advantage that the traditional algorithm can not compared. Genetic algorithm uses multi-point search. In each iteration, the new individuals are generated...
It's very important to detect the leakage of oil pipeline timely and accurately in order to reduce the losses and ensure the smooth operation of oil pipeline. However, the leakage monitoring of the pipeline is difficult because normally the pipeline is very long and is often buried underground or underwater. Brillouin optical time domain reflectometry (BOTDR), which can distributedly measure the temperature...
Exploratory search is cumbersome with today's search engines, where a user aims to better understand complex concepts. Query expansions techniques have been widely used in exploratory search. However, query expansions often recommend queries that differ from the user's search intentions due to different contexts. Yet, many of users' needs could be addressed by asking people via popular Community Question...
Cooperative spectrum sensing schemes can enable cognitive radio (CR) users to efficiently identify the unoccupied channels or spectrum holes, as well as overcome the impact of shadowing and fading. Considering the hardware limitation, compressive sensing (CS) is a solution scheme to alleviate the requirements on the receiver hardware, which can recover the wideband sparse signal sampled at sub-Nyquist...
Influence maximization aims to find a set of highly influential nodes in a social network to maximize the spread of influence. The most difficult part of the problem is to estimate the influence spread of any seed set, which has been proved to be #P-hard. There is no efficient method to estimate the influence spread of any seed set till now. Thus, the most common way to obtain the approximate influence...
To effectively monitor targets of interest, it's necessary to be aware of the object's movement direction in a monitored area. For this purpose, we propose a simple and accurate movement direction estimation method to determine the movement direction of tagged object through a Radio Frequency Identification (RFID)-based system, using the variation tendency of the signal phase received by two antennas...
In this paper, we propose a control algorithm to achieve consensus of multi-agent systems with time delay and heterogeneous topologies. The proposed control scheme is capable of dealing with both velocity and position time delay. The stability analysis is conducted based on Lyapunov method and graph theory and provides the proof that consensus of multi-agent systems can be achieve if the time delay...
This paper concerns four new oscillatory theorems to the second-order p-Laplacian dynamic equation with delay on time scales equation. The results improve and extend some known theorems.
Using a suitable algebraic setup, we find new estimates of the quantum capacity and the potential quantum capacity for non-degradable channels obtained by random unitaries associated with a finite group. This approach can be generalized to quantum groups and uses new tools from operator algebras and interpolation of Rényi-type entropies. As an application, we obtain new estimates for the depolarizing...
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