weak pulse
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2021 ◽  
Vol 20 (9) ◽  
pp. 944-946
Author(s):  
A. V. Khokhlova

In addition to the typical signs, what are the pallor of the skin and mucous membranes, frequent, weak pulse, fainting, etc., internal bleeding that occurs as a result of rupture of the fetus during an ectopic pregnancy is accompanied by other, no less characteristic phenomena from various systems organism, which sometimes make it possible to timely confirm or establish a diagnosis and differentiate this suffering from other similar painful conditions.


2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Liyun Su ◽  
Meini Li ◽  
Shengli Zhao ◽  
Ting Xie

This paper combines the distributed sensor fusion system with the signal detection under chaotic noise to realize the distributed sensor fusion detection from chaotic background. First, based on the short-term predictability of the chaotic signal and its sensitivity to small interference, the phase space reconstruction of the observation signal of each sensor is carried out. Second, the distributed sensor local linear autoregressive (DS-LLAR) model is constructed to obtain the one-step prediction error of each sensor. Then, we construct a Bayesian risk model and also obtain the corresponding conditional probability density function under each sensor’s hypothesis test which firstly needs to fit the distribution of prediction errors according to the parameter estimation. Finally, the fusion optimization algorithm is designed based on the Bayesian fusion criterion, and the optimal decision rule of each sensor and the optimal fusion rule of the fusion center are jointly solved to effectively detect the weak pulse signal in the observation signal. Simulation experiments show that the proposed method which used a distributed sensor combined with a local linear model can effectively detect weak pulse signals from chaotic background.


2020 ◽  
Vol 9 (10) ◽  
pp. 823-825
Author(s):  
N. K. Neyolov

On December 19, 1894, sick Eleanor M ko, diagnosed with polypus uteri, was sent to me by a comrade of the land. Arriving to the patient at the hotel, I found her in a very bad state: deathly pale, with a very weak pulse, with t to 40.0 ; dirty blood with a strongly putrid odor was discharged from the vagina. The patient was immediately sent to the hospital, where a thorough examination gave the following: the patient is of medium height, the skeletal system is developed correctly, muscles and skin are flabby; the outer covers are very pale; the visible mucous membranes are very pale with a cyanotic tinge; heart, lungs, and urine are normal. External genitals, heavily soiled with a dirty red fluid, are normal; first degree perineal rupture; the genital gap gapes a little; 2 snt. from the entrance to the vagina, the finger comes across a round, rather soft and elastic body, reminiscent, at first impression, of a fibrous polyp; this body, the size of a slightly enlarged uterus, has only a round outline below; above it tapers and passes into a small groove, limited by the external os of the uterus. In place of the body of the uterus, a small solid formation is felt, the size of a slightly enlarged ovary; this formation closes a funnel, which in this case cannot be felt; nothing pathological is felt in the vaults. When viewed in mirrors, the described body appears to be a dirty gray color, in places even completely black; at the slightest touch, the body bleeds quite a lot. The patient's body temperature is 39.6 C., pulse 120, very weak and easily compressed; the patient cannot move without assistance.


Complexity ◽  
2020 ◽  
Vol 2020 ◽  
pp. 1-14
Author(s):  
Liyun Su ◽  
Xiu Ling

In target estimating sea clutter or actual mechanical fault diagnosis, useful signal is often submerged in strong chaotic noise, and the targeted signal data are difficult to recover. Traditional schemes, such as Elman neural network (ENN), backpropagation neural network (BPNN), support vector machine (SVM), and multilayer perceptron- (MLP-) based model, are insufficient to extract the weak signal embedded in a chaotic background. To improve the estimating accuracy, a novel estimating method for aiming at extracting problem of weak pulse signal buried in a strong chaotic background is presented. Firstly, the proposed method obtains the vector sequence signal by reconstructing higher-dimensional phase space data matrix according to the Takens theorem. Then, a Jordan neural network- (JNN-) based model is designed, which can minimize the error squared sum by mixing the single-point jump model for targeting signal. Finally, based on short-term predictability of chaotic background, estimation of weak pulse signal from the chaotic background is achieved by a profile least square method for optimizing the proposed model parameters. The data generated by the Lorenz system are used as chaotic background noise for the simulation experiment. The simulation results show that Jordan neural network and profile least square algorithm are effective in estimating weak pulse signal from chaotic background. Compared with the traditional method, (1) the presented method can estimate the weak pulse signal in strong chaotic noise under lower error than ENN-based, BPNN-based, SVM-based, and -ased models and (2) the proposed method can extract the weak pulse signal under a higher output SNR than BPNN-based model.


2020 ◽  
Vol 2020 ◽  
pp. 1-12 ◽  
Author(s):  
Liyun Su ◽  
Li Deng ◽  
Wanlin Zhu ◽  
Shengli Zhao

Weak signal detection is a significant problem in modern detection such as mechanical fault diagnosis. The uniqueness of chaos and good learning ability of neural networks provide new ideas and framework for weak signal detection field. In this paper, Elman neural network is applied to detect and recover weak pulse signal in chaotic noise. For detection problem of weak pulse signal under chaotic noise, based on short-term predictability of chaotic observations, phase space reconstruction for observed signals is carried out. And Elman deep learning adaptive detection model (EDAD model) is established for weak pulse signal detection, and a hypothesis test is used to detect weak pulse signal from the prediction error. For the recovery of weak pulse signal under chaotic noise, a double-layer Elman deep neural network recovery model (DEDR model) is proposed, which is based on the Elman deep learning network model and single-point jump model for weak pulse signal, and it is optimized with goal of minimizing mean square prediction error of the Elman model. The profile least squares method is applied to estimate parameters of the DEDR model for difficult recovery of weak pulse signal because the DEDR model is essentially a semiparametric model with parametric and nonparametric parts. In the end, simulation experiments show that the model built in this paper can effectively detect and recover weak pulse signal in the background of chaotic noise.


2019 ◽  
Vol 2019 ◽  
pp. 1-12 ◽  
Author(s):  
Liyun Su ◽  
Li Deng ◽  
Wanlin Zhu ◽  
Shengli Zhao

With the development in communications, the weak pulse signal is submerged in chaotic noise, which is very common in seismic monitoring and detection of ocean clutter targets, and is very difficult to detect and extract. Based on the threshold autoregressive model, pulse linear form, Markov chain Monte Carlo (MCMC), and profile least squares (PrLS) algorithm, phase threshold autoregressive (PTAR) model and double layer threshold autoregressive (DLTAR) model are proposed for detection and extraction of weak pulse signals in chaotic noise, respectively. Firstly, based on noisy chaotic observation, phase space is reconstructed according to Takens’s delay embedding theorem, and the phase threshold autoregressive (PTAR) model is presented to detect weak pulse signals, and then the MCMC algorithm is applied to estimate parameters in the PTAR model; lastly, we obtain one-step prediction error, which is used to realize adaptively detection of weak signals with the hypothesis test. Secondly, a linear form for the pulse signal and PTAR model is fused to build a DLTAR model to extract weak pulse signals. The DLTAR model owns two kinds of parameters, which are affected mutually. Here, the PrLS algorithm is applied to estimate parameters of the DLTAR model and ultimately extract weak pulse signals. Finally, accurate rate (Acc), receiver operating characteristic (ROC) curve, and area under ROC curve (AUC) are used as the detector performance index; mean square error (MSE), mean absolute percent error (MAPE), and relative error (Re) are used as the extraction accuracy index. The presented scheme does not need prior knowledge of chaotic noise and weak pulse signals, and simulation results show that the proposed PTAR-DLTAR model is significantly effective for detection and extraction of weak pulse signals under chaotic interference. Specifically, in very low signal-to-interference ratio (SIR), weak pulse signals can be detected and extracted compared with support vector machine (SVM) class and neural network model.


Author(s):  
Jiaoyan Wang ◽  
Xiaoshan Zhao ◽  
Chao Lei

AbstractInputs can change timings of spikes in neurons. But it is still not clear how input’s parameters for example injecting time of inputs affect timings of neurons. HR neurons receiving both weak and strong inputs are considered. How pulse inputs affecting neurons is studied by using the phase-resetting curve technique. For a single neuron, weak pulse inputs may advance or delay the next spike, while strong pulse inputs may induce subthreshold oscillations depending on parameters such as injecting timings of inputs. The behavior of synchronization in a network with or without coupling delays can be predicted by analysis in a single neuron. Our results can be used to predict the effects of inputs on other spiking neurons.


2019 ◽  
Vol 68 (8) ◽  
pp. 080501
Author(s):  
Bao-Feng Cao ◽  
Peng Li ◽  
Xiao-Qiang Li ◽  
Xue-Qin Zhang ◽  
Wang-Shi Ning ◽  
...  

2018 ◽  
Vol 27 (2) ◽  
pp. 024206
Author(s):  
Xue-Fei Pan ◽  
Jun Zhang ◽  
Shuai Ben ◽  
Tong-Tong Xu ◽  
Xue-Shen Liu

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