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Recent progress in gas nanobubble electrochemistry

Yulong Liu, Cheng Jin, Yuwen Liu, Qianjin Chen
2020 Scientia Sinica Chimica  
doi:10.1360/ssc-2020-0149 fatcat:wcldet5acvdmvfsz2kqbwtqhgm

Multifeature Deep Cascaded Learning for PPG Biometric Recognition

Chunying Liu, Yuwen Huang, Fuxian Huang, Jijiang Yu, Debo Cheng
2022 Scientific Programming  
Aiming at the problem that the traditional photoplethysmography (PPG) biometric recognition based on sparse representation is not robust to noise and intraclass variations when the sample size is small, we propose a PPG biometric recognition method based on multifeature deep cascaded sparse representation (MFDCSR). The method consists of multifeature signal coding and deep cascaded coding. The function of multifeature signal coding is to extract the shape, wavelet, and principal component
more » ... is features of the PPG signal and to perform sparse representation. Deep cascaded coding is multilayer feature coding. Each layer combines multifeature signal coding with the result of the previous layer as input, and the output of each layer is the input of the next layer. The function of deep cascade coding is to learn the features of the PPG signal, layer by layer, and to output the category distribution vector of the PPG signal in the last layer. Experiments demonstrate that MFDCSR has better recognition performance than current methods for PPG biometric recognition.
doi:10.1155/2022/7477746 fatcat:22zvkcqocbd45c65w336zw26l4

A dynamic model for a class of semi-autogenous mill systems

Cheng Yuwen, Bo Sun, Shuai Liu
2020 IEEE Access  
In this paper, we develop a state space model of semi-autogenous (SAG) mill systems, which is of great significance to the mineral processing control. According to the practical enterprise production condition, the model is composed of two main parts. One is the ore circuit model. Compared with other models of ore circuit, the present model is simple and efficient. Another part is the SAG subsystem model where the state space model is utilized to depict the grinding mechanism. Furthermore, the
more » ... rinding process of hold-ups are analyzed and presented with the common outputs such as power draw, pulp density and pulp flow. We consider the mass of rocks, granules and water as states and analyze the observability of the SAG subsystem model. For the ore circuit system and the SAG subsystem established respectively, unknown parameters of these models are identified by appropriate parameter estimation methods. Verified by the actual plant data, the result shows that the SAG mill system works well. INDEX TERMS SAG mill system, dynamic model, parameter identification. 98460 This work is licensed under a Creative Commons Attribution 4.0 License. For more information, see https://creativecommons.org/licenses/by/4.0/ VOLUME 8, 2020
doi:10.1109/access.2020.2997052 fatcat:aag6vwlof5fsvcxv6jb7y5dexa

Model-aided Deep Neural Network for Source Number Detection [article]

Yuwen Yang, Feifei Gao, Cheng Qian, Guisheng Liao
2019 arXiv   pre-print
Source number detection is a critical problem in array signal processing. Conventional model-driven methods e.g., Akaikes information criterion (AIC) and minimum description length (MDL), suffer from severe performance degradation when the number of snapshots is small or the signal-to-noise ratio (SNR) is low. In this paper, we exploit the model-aided based deep neural network (DNN) to estimate the source number. Specifically, we first propose the eigenvalue based regression network (ERNet) and
more » ... classification network (ECNet) to estimate the number of non-coherent sources, where the eigenvalues of the received signal covariance matrix and the source number are used as the input and the supervise label of the networks, respectively. Then, we extend the ERNet and ECNet for estimating the number of coherent sources, where the forward-backward spatial smoothing (FBSS) scheme is adopted to improve the performance of ERNet and ECNet. Numerical results demonstrate the outstanding performance of ERNet and ECNet over the conventional AIC and MDL methods as well as their excellent generalization capability, which also shows their great potentials for practical applications.
arXiv:1909.13273v2 fatcat:57wgidt7tnh4pbeb4vyjeuihaa

The existence and uniqueness of strong kings in tournaments

An-Hang Chen, Jou-Ming Chang, Yuwen Cheng, Yue-Li Wang
2008 Discrete Mathematics  
A king x in a tournament T is a player who beats any other player y directly (i.e., x → y) or indirectly through a third player z (i.e., x → z and z → y). For x, y ∈ V (T ), let b(x, y) denote the number of third players through which x beats y indirectly. Then, a king x is strong if the following condition is fulfilled: b(x, y) > b(y, x) whenever y → x. In this paper, a result shows that for a tournament on n players there exist exactly k strong kings, 1 k n, with the following exceptions: k =
more » ... n − 1 when n is odd and k = n when n is even. Moreover, we completely determine the uniqueness of tournaments.
doi:10.1016/j.disc.2007.05.008 fatcat:djiyynwgwrdm7hhorl7qpzeola

China's Stance on Investor-State Dispute Settlement: Evolution, Challenges, and Reform Options

Yuwen Li, Cheng Bian
2020 Netherlands International Law Review  
AbstractChina is one of the most active states in concluding bilateral investment treaties (BITs) globally. Its BITs can be categorized into three generations based on the homogeneity of the investor-state dispute settlement (ISDS) provisions within each generation. The China–EU Comprehensive Agreement on Investment and the China–US BIT under negotiation are expected to inaugurate a fourth generation, although China's stance on ISDS in both treaties remains indeterminate. This article
more » ... on the distinctive characteristics of ISDS provisions by mapping three generations of Chinese BITs, presenting the challenges that these ISDS provisions have brought to light in investor-state adjudication as well as in the context of the Belt and Road Initiative, and expounding on China's policy options in ISDS reform. The on-going intense debate on ISDS reform presents China with an opportunity to shift from its traditional role of a rule-taker to a rule-maker in redesigning the ISDS mechanism. However, China's current policy and practice do not demonstrate an ambition for such a transformation. Looking forward, it may well be in China's long-term interest to endorse a Multilateral Investment Court as vigorously advocated by the EU.
doi:10.1007/s40802-020-00182-3 fatcat:f33hmybl7ff6jm7kz42ugitgoi

Thermal ablation of metal films by femtosecond laser bursts

Yunpeng Ren, C.W. Cheng, J.K. Chen, Yuwen Zhang, D.Y. Tzou
2013 International journal of thermal sciences  
Thermal ablations of metal films by a single femtosecond laser pulse and by a laser burst were investigated using a comprehensive computational model, including a two-temperature model with dynamic optical properties, two phase change models for melting and evaporation under superheating, and a phase explosion criterion for ejection of the mixture of metastable liquid droplets and vapor. Numerical simulations were performed for copper films. The simulation of material ablation by the single
more » ... e showed a good agreement with existing experimental data for a broad range of laser fluence 0.6e30 J/ cm 2 . In the study of material ablation by femtosecond laser bursts, it was found that under the same total fluence a laser burst with a pulse separation time of 50 ps or longer can significantly boost the ablation rate, compared to the single pulse. It was also demonstrated that for a given total fluence the ablation rate can be optimized by selecting a proper combination of pulse number and separation time in a laser burst.
doi:10.1016/j.ijthermalsci.2013.03.003 fatcat:m3x2t4eyvbgl5akru2eka7wobm

The Effects of 0.01% Atropine on Adult Myopes' Contrast Sensitivity

Ziyun Cheng, Jianhui Mei, Suqi Cao, Ran Zhang, Jiawei Zhou, Yuwen Wang
2021 Frontiers in Neuroscience  
The eye drops were given by the authors (Z Cheng and J Mei), and the participants were unaware of which eye drop was given.  ... 
doi:10.3389/fnins.2021.624472 pmid:33679306 pmcid:PMC7933202 fatcat:6yok7udqivdw7lpepnvnrm65pm

IRD: An Approach to Protect IPv6 Neighbor Cache

Ya-zhou KONG, Zhen-xing WANG, Lian-cheng ZHANG, Hui-qiang YUWEN
2017 DEStech Transactions on Computer Science and Engineering  
Reverse Detection (RD) is an IPv6 Neighbor Cache (NC) protection approach. Since the RD message has no protection mechanism, an attacker can forge RD reply packet to avoid the approach. This paper presents an Improved Reverse Detection (IRD) approach, a timestamp and a packet sequence are introduced to limit the response time and response packet matching respectively; then, define the IRD queue to store timestamp and packet sequence number and other information, and design a Random Early
more » ... on (RED) algorithm based on timestamp to prevent DoS. Our experiment result shows that IRD can effectively resist the neighbor cache spoofing and DoS, compared with the existing approaches, the CPU occupancy rate decreased by 8.31% and neighbor cache update accuracy increased by 4.53%.
doi:10.12783/dtcse/cst2017/12513 fatcat:p4ghqb2baber3jcoh6zoaeukhe

A Comprehensive Nuclear Receptor Network for Breast Cancer Cells

Ralf Kittler, Jie Zhou, Sujun Hua, Lijia Ma, Yuwen Liu, Elisha Pendleton, Chao Cheng, Mark Gerstein, Kevin P. White
2013 Cell Reports  
In breast cancer, nuclear receptors (NRs) play a prominent role in governing gene expression, have prognostic utility, and are therapeutic targets. We built a regulatory map for 24 NRs, six chromatin state markers, and 14 breast-cancer-associated transcription factors (TFs) that are expressed in the breast cancer cell line MCF-7. The resulting network reveals a highly interconnected regulatory matrix where extensive crosstalk occurs among NRs and other breast -cancer-associated TFs. We show
more » ... large numbers of factors are coordinately bound to highly occupied target regions throughout the genome, and these regions are associated with active chromatin state and hormone-responsive gene expression. This network also provides a framework for stratifying and predicting patient outcomes, and we use it to show that the peroxisome proliferator-activated receptor delta binds to a set of genes also regulated by the retinoic acid receptors and whose expression is associated with poor prognosis in breast cancer.
doi:10.1016/j.celrep.2013.01.004 pmid:23375374 fatcat:avxrryvknjeyloz7ebirn2p2cy

Thermal effect on the compression coefficient of heavy oil reservoir rocks

Zhang Chao, Yan Chuanliang, Liu Yuwen, Li Yang, Cheng Yuanfang, Tian Ji
2018 Royal Society Open Science  
The ever-decreasing oil resources receive more and more attention for the exploration and development of heavy oil reservoirs. Owing to the high viscosity and poor fluidity of heavy oil, it is necessary to use the method of injecting high-temperature fluid in the development process. But, this will cause a significant increase in the temperature in oil reservoir, and thus the compression coefficient of reservoir rock has a greater impact. The compression coefficient of heavy oil reservoirs at
more » ... fferent temperatures was tested. The results show that the compression coefficient of rock is closely related to the nature of rock itself and its stress and temperature environment: the compression coefficient increases with the increase in rock porosity; the compression coefficient decreases with the increase in the effective confining pressure and increases with the increase in temperature. When the temperature is low, the increase in the compression coefficient is larger. As the temperature increases, the increase in the compression coefficient tends to decrease gradually. Because the temperature of the reservoir is higher than that of the ground, the influence of the temperature on the reservoir compression coefficient should be taken into account when carrying out the production forecast.
doi:10.1098/rsos.180534 pmid:30109099 pmcid:PMC6083679 fatcat:mdpq5fxfsjfwten4j4akdofsii

The Changes of T-Wave Amplitude and QT Interval Between the Supine and Orthostatic Electrocardiogram in Children With Dilated Cardiomyopathy

Cheng Tan, Xiuying Yi, Ying Chen, Shuangshuang Wang, Qing Ji, Fang Li, Yuwen Wang, Runmei Zou, Cheng Wang
2021 Frontiers in Pediatrics  
Objectives: Electrocardiogram (ECG) can be affected by autonomic nerves with body position changes. The study aims to explore the ECG changes of children with dilated cardiomyopathy (DCM) when their posture changes.Materials and methods: Sixty-four children diagnosed with DCM were recruited as research group and 55 healthy children as control group. T-wave amplitude and QT interval in ECG were recorded, and their differences between supine and orthostatic ECG were compared in both groups.
more » ... uently, the children with DCM were followed up and the differences before and after treatment compared.Results: ① Comparisons in differences: Differences of T-wave amplitude in lead II and III, aVF, and V5 and differences of QT interval in lead II, aVL, aVF, and V5 were lower in the research group than in the control group. ② Logistic regression analysis and diagnostic test evaluation: The differences of T-wave amplitude in lead III and QT interval in lead aVL may have predictive value for DCM diagnosis. When their values were 0.00 mV and 30 ms, respectively, the sensitivity and specificity of the combined index were 37.5 and 83.6%. ③ Follow-up: In the response group, the T-wave amplitude difference in lead aVR increased and the difference of QT interval in lead V6 decreased after treatment. In the non-response group, there was no difference before and after treatment. When the combined index of the differences of T-wave amplitude difference in lead aVR and QT interval difference in lead V6, respectively, were −0.05 mV and 5 ms, the sensitivity and specificity of estimating the prognosis of DCM were 44.4 and 83.3%.Conclusions: The differences of T-wave amplitude and QT interval may have a certain value to estimate DCM diagnosis and prognosis.
doi:10.3389/fped.2021.680923 fatcat:54nsmb5jb5e27jgrngybappavy

Photoacoustic Mouse Brain Imaging Using an Optical Fabry-Pérot Interferometric Ultrasound Sensor

Yuwen Chen, Buhua Chen, Tengfei Yu, Lu Yin, Mingjian Sun, Wen He, Cheng Ma
2021 Frontiers in Neuroscience  
Photoacoustic (PA, or optoacoustic, OA) mesoscopy is a powerful tool for mouse cerebral imaging, which offers high resolution three-dimensional (3D) images with optical absorption contrast inside the optically turbid brain. The image quality of a PA mesoscope relies on the ultrasonic transducer which detects the PA signals. An all-optical ultrasound sensor based on a Fabry-Pérot (FP) polymer cavity has the following advantages: broadband frequency response, wide angular coverage and small
more » ... int. Here, we present 3D PA mesoscope for mouse brain imaging using such an optical sensor. A heating laser was used to stabilize the sensor's cavity length during the imaging process. To acquire data for a 3D angiogram of the mouse brain, the sensor was mounted on a translation stage and raster scanned. 3D images of the mouse brain vasculature were reconstructed which showed cerebrovascular structure up to a depth of 8 mm with high quality. Imaging segmentation and dual wavelength imaging were performed to demonstrate the potential of the system in preclinical brain research.
doi:10.3389/fnins.2021.672788 pmid:34079437 pmcid:PMC8165253 fatcat:tprwzi5uzjb3rlvnwa7hmxlz7y

Characterization of NaA Zeolite Oxygen Permeable Membrane on TiO2/α-Al2O3Composite Support

Mengfu Zhu, Hongbo Su, Cheng Deng, Linlin Yuwen, Mingming Jiang, M. Jawaid, El-R. Kenawy
2016 MATEC Web of Conferences  
The NaA zeolite membrane was synthesized on the surface of TiO 2 /Į-Al 2 O 3 composite support with TiO 2 as modifier of Į-Al 2 O 3 porous tubular ceramic membrane support by crystallization method. The structure characterization indicated that the TiO 2 of the support surface could effectively improve the surface properties of the support. It didn't affect the crystallization of NaA synthesis liquid and synthesis process of NaA zeolite membrane. There were no obvious defects between the
more » ... particles with size of approximate 6ȝm. The perfect and complete membrane with thickness of approximate 15ȝm combined closely with support to connection together by TiO 2 modified. The oxygen permeability of the membrane on TiO 2 /Į-Al 2 O 3 composite support improves of 47% compared with that of Į-Al 2 O 3 support. So the process of TiO 2 modifying the surface of Į-Al 2 O 3 support should increase the oxygen permeability of the NaA zeolite membrane.
doi:10.1051/matecconf/20166706003 fatcat:p6pgvff3vvb35jbw3o3aozoxxa

Address and Port Knocking Mechanism for Concealed Authentication

Leyi Shi, Xiao Wen, Zijing Cheng, Yuwen Cui, Yi Lu
2017 Innovative Computing Information and Control Express Letters, Part B: Applications  
Authentication is a mechanism to distinguish the legitimate users from attackers who intend to access services illegally through open ports. This paper focuses on the authentication problem in network security. We firstly put up the address and port knocking (APK) authentication scheme to build a credible connection between the client and the server. Then the approach of randomly generating sequence and the sending of the knocking packets are discussed in detail. Thereafter, a matrix transpose
more » ... ultiplication algorithm is presented to identify the knocking sequence by checking the destination addresses and ports. Experiments are launched to validate the performance of our scheme. The empirical results reveal that the APK authentication scheme is efficient and feasible.
doi:10.24507/icicelb.08.03.511 fatcat:lf2qvbv5bfhypgzayuvfwxfobu
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