Background Functional near-infrared spectroscopy (fNIRS) identifies neurophysiological differences between psychiatric disorders by assessing cortical hemodynamic function. Few trials have studied in brain functional activity first-episode medication-naïve depression patients (FMD) and recurrent major (RMD). We aimed to determine the FMD RMD oxygenated hemoglobin concentration ([oxy-Hb]), investigate correlation frontotemporal cortex activation clinical symptoms. Methods recruited 40 with...

Due to the randomness of added noise, noise-assisted versions based on EMD (empirical mode decomposition) usually cause new “mode mixing” problem. In addition, these algorithms also have problems such as high time-consuming and large recovering error. For reasons, a method SN-EMD (Selective Noise-assisted EMD) is put forward in this paper. It determines whether add noise assistance by judging there frequency intermittent component contained signal or not. The was proved optimal performance...

Pattern time delay shift coding scheme uses the values of to code information whose anti-ISI (intersymbol interference) ability is related kind and duration Pattern. Spread spectrum communications competent for long-range underwater acoustic its spread gain, but low rate seriously restricts application. The proposed new adapted environment, which integrates with works at M-ary mode several channels. could achieve good performance also improve data transfer rate. results lake trial show that...

This paper proposes a composite channel virtual time reversal mirror (CCVTRM) for vertical sensor array (VSA) processing and applies it to long-range underwater acoustic (UWA) communication in shallow water. Because of weak signal-to-noise ratio (SNR), is unable accurately estimate the impulse response each VSA, thus traditional passive (PTRM) cannot perform well UWA However, CCVTRM only needs VSA accomplish (TRM), which can effectively mitigate inter-symbol interference (ISI) reduce bit...

The technique of pattern time delay shift coding (PDS) underwater acoustic (UWA) communication based on parametric array is presented in this paper, which easy to be implemented and robust the spatiotemporal variable ocean environment. can generate low-frequency, broadband, high-directivity beam with small-aperture. high directivity reduces impact variant characteristics UWA channel especially multipath effects improves reuse rate at same time. wide bandwidth allows communications. sea trial...

Due to the significant multipath and Doppler effects in underwater acoustic (UWA) channel, quality of received signal is degraded, which seriously affects performance UWA communication. The paper proposes a time reversal communication method combined with symbol-based compensation (SBDC) technique solve those problems. A single element mirror (TRM) used realize channel equalization mitigate inter-symbol interference (ISI) resulting from propagation. SBDC subsequently compensate signal,...

Abstract A novel and efficient covert underwater acoustic (UWA) communication scheme using an parametric array orthogonal frequency division multiplexing (OFDM) system is presented. The proposed robust can easily be implemented in the ocean environment. also very useful military applications where secrecy of transmission signal location transmitter are extremely important. paper exploits difference generated by due to nonlinear behavior medium. Besides lightness compactness, possesses...

Time reversal (TR) can achieve temporal and spatial focusing by exploiting diversity in complex underwater environments with significant multipath. This property makes TR useful for acoustic (UWA) communications. Conventional is realized performing equal gain combining (EGC) on the single element output signals of each vertical receive array (VRA). However, actual environment, signal-to-noise ratio (SNR) received noise power are different, which leads to reduction gain. paper proposes a time...

With the rapid development of automobile industry, auto parts logistics emerged as an important part promoting industrial development. Milk-run is used more and frequent in supply. Based on characteristics requirement milk-run, order to satisfy OEMs, distribution center takes milk-run supply model a variety vendors, using idea third party. The design vehicle routing problem designing non-full set goods with time window. This thesis established window, studied parts, particle swarm...

Estimating the direction of arrival (DOA) spatially spread sources is a significant challenge in array signal processing. This work introduces an effective method within sparse Bayesian framework to tackle this issue. A source modeled using multi-dimensional Slepian subspace that expands dictionary and results block-sparse structured solution. By taking advantage learning, parameter estimation becomes feasible. complex Gaussian posterior derived under multi-snapshot with prior varying noise...

This paper is under in-depth investigation due to suspicion of possible plagiarism on a high similarity index Low Density Parity Check Code（LDPC） kind linear block codes based sparse check matrix. As channel coding, whose error performance approach Shannon limits, it has better correction capability, more flexible structure and lower decoding complexity. Currently most the LDPC code researches are premise AWGN BSC channel, which mainly in range binary codes. According above problem, this...

In the calculation of underwater acoustic positioning, errors element position measurement, time delay attitude accuracy and sound velocity measurement will lead to final positioning solution. The optimization method solution is also one key technologies location traditional statistical methods mostly use arithmetic average Newton iteration method. this paper, particle swarm based on simulated annealing used improve estimation effectiveness verified by computer simulation comparative...

On the basis of bubble oscillation theory and its modified model, by using Runge-Kutta algorithm, airgun source signal wavelets are obtained. Through simulation, impacts different sound parameters on wave quality studied consistency is verified. Using sonar equation, method calculating transmission distance theoretically given. The spectrum calculated. channel simulated under normal mode model ray same working conditions. used as transmitting signal. So two kinds signals received spectrums...

The technology of focused beam forming is mainly used for solving some certain problems about high-precision passive positioning in near field. In view the problem accuracy, this paper discusses effects factors on width peak and its changes with factors. result study shows longer arrays length higher frequency band signal shorter distance to target, narrower peak, which means accuracy. influence errors accuracy also simulated analyzed paper. It turned out that, when horizontal linear array...

Focused beam forming is measurement technology with high precision. In this article, we put forward a 3D passive positioning method based on focused for the first time. Fixing hydrophone array bottom of sea, it received sound through multi-path channel from target. Direct and sea return formed two bright spots in acoustic image measured by forming. From coordination elements, as well scanning depth, calculated position It also provides to track underwater moving targets. Simulation confirmed...

With the proposal of carbon capture and storage technology, seabed technology has become an effective way to change climate change. This paper proposes optimization UUV self-localization method solve problem less accurate feedback leakage location sequestration. The employs a hyperbolic intersection model uses improved generalized cross correlation algorithm based on PATH weighting for time delay estimation. localization is also solved using joint Chan&Taylor algorithm. enables leak...

The traditional mode of the automobile manufacturing enterprise (ECL) integration is reviewed firstly. Relying on distribution center and its information platform according to development trend manufacturing, a new mode——supply chain logistics intensive operation put forward. process characteristics this are analyzed; logical model established. At end, article analyzes significance car industry.

Objective To explore the effects of targeted health education and appropriate turning-over scheme on prognosis pressure sores in old stroke patients.Methods A total 225 patients were divided into three groups.The control group received routine nursing turning over methods,the observation Ⅰ basis group,the Ⅱ circulating methods.Results The incidences obviously lower than that while hospital.After education,the awareness rates prevention knowledge skills family members increased obviously.The...

Instantaneous frequency and time-delay measured accurately are important technologies for high precise underwater positioning. In order to prevent the leakage interference from other channels, variability of instantaneous sequence (VIFS) calculation estimations were adopted. The synchronous positioning model (spherical) combined with asynchronously (hyperbolical) overcomes ambiguous ranging rate trace. At last, results sea experiment provided, that met theory.