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An SIR epidemic model with free boundary [article]

Kwang Ik Kim, Zhigui Lin, Qunying Zhang
2013 arXiv   pre-print
An SIR epidemic model with free boundary is investigated. This model describes the transmission of diseases. The behavior of positive solutions to a reaction-diffusion system in a radially symmetric domain is investigated. The existence and uniqueness of the global solution are given by the contraction mapping theorem. Sufficient conditions for the disease vanishing or spreading are given. Our result shows that the disease will not spread to the whole area if the basic reproduction number R_0<1
more » ... or the initial infected radius h_0 is sufficiently small even that R_0>1. Moreover, we prove that the disease will spread to the whole area if R_0>1 and the initial infected radius h_0 is suitably large.
arXiv:1302.0326v1 fatcat:inpzpsvbwbcrtih5w3p3it7oqy

Stepped Frequency Multiresolution Digital Signal Processing

Qunying Chen, Yi-Zhang Jiang
2021 Scientific Programming  
With the rapid development of radar industry technology, the corresponding signal processing technology becomes more and more complex. For the radar with short-range detection function, its corresponding signal mostly presents the characteristics of wide bandwidth and multiresolution. In the traditional data processing process, a large number of signals will interfere with the signal, which makes the final signal processing difficult or even impossible. Based on this problem, this paper
more » ... a principal component linear prediction processing algorithm based on clutter suppression processing on the basis of traditional signal processing algorithm. According to the curve characteristics of the data returned by the target detected by the signal, through certain image signal measurement and transformation, the clutter can be effectively suppressed and the typical characteristics of the corresponding target curve can be enhanced. For the convergence problem of signal processing and the corresponding image chromatic aberration compensation problem, this paper will realize the chromatic aberration compensation of the corresponding target echo image based on the radial pointing transverse mode algorithm and enhance the convergence speed of the whole algorithm system. In the experimental part of this paper, the optimization algorithm proposed in this paper is compared with the traditional algorithm. The experimental results show that the algorithm proposed in this paper has obvious advantages in the convergence of signal processing and antijamming performance and has the promotion value.
doi:10.1155/2021/9081988 fatcat:3mtzzsfmtfdflknak5xidotlva

Spatial Segregation Limit of a Quasilinear Competition-Diffusion System

Qunying Zhang, Shan Zhang, Zhigui Lin
2015 Applied Mathematics  
Zhang et al. in particular, in the case when the interactions are large and of competitive type.  ... 
doi:10.4236/am.2015.612175 fatcat:cn5dmgli45einjj55dxhmntcfu

Speed Regulation of Permanent Magnet Synchronous Motor Using Event Triggered Sliding Mode Control

Huan Zhang, Qunying Liu, Jiashu Zhang, Shuheng Chen, Changhua Zhang
2018 Mathematical Problems in Engineering  
To reduce the chattering issue and improve the dynamic tracking performance of the speed regulation of the permanent magnet synchronous motor (PMSM) system, the sliding mode control (SMC) with an enhanced exponential reaching law (EERL) is proposed in this paper. Compared to the SMC with conventional reaching law (CRL), the proposed SMC based on the EERL makes the convergence rate be associated with the change of the system state variable. In order to implement the minimum resource utilization
more » ... f the embedded processor while guaranteeing the performance of the system, the event triggered strategy is developed for SMC, which possesses the excellent robustness and saves the energy cost. The stability of the event triggered SMC control law is proved by the Lyapunov function and the minimum control execution time interval is also derived. Finally, the effectiveness of the proposed EERL and the satisfactory performance of the event triggered SMC are demonstrated by the simulation results.
doi:10.1155/2018/2394535 fatcat:43pumm6ivvhuzoo4r3cgn4cbaq

Fuzzy Keywords-driven Public Sports Resource Allocation Strategies Retrieval with Privacy-preservation

Yong Sang, Qiyun Zhang, Kuilin Zhang, Dongxing Wang, Qunying Yuan, Hanwen Liu
2020 IEEE Access  
Currently, the government proposes various public sports resource allocation strategies to promote the construction of public sports in the local. Thus, searching for the document database becomes an economic and efficient way for government officials to understand the contents of various public sports resource allocation strategies. As the government officials lack background knowledge of public sports resource allocation, the government officials are hard to retrieve appropriate documents.
more » ... t's more, the document database is generally unwilling to share all text document information with the government official as some documents contain sensitive data information. Considering the above drawbacks, we put forward a fuzzy keywords-driven public sports resource allocation strategies retrieval approach based on the Simhash (named PSRASk+S) in the paper. The retrieval approach can accurately recommend appropriate documents to the government officials, by using the text description mining of documents and the fuzzy keywords search technology. Furthermore, the retrieval process is not revealing the sensitive data information of the irrelevant public sports resource allocation strategy document to the government officials, so the retrieval process can achieve local information protection mechanism. Finally, a case study explains the feasibility and effectiveness of our retrieval approach step by step.
doi:10.1109/access.2020.3033551 fatcat:4gcekegjvjhunb4wyxyxeme4mm

Impact of linker-drug on ion exchange chromatography separation of antibody-drug conjugates

Zhaorui Zhang, Shiyue Zhou, Linjie Han, Qunying Zhang, Wayne A. Pritts
2019 mAbs  
Zhaorui Zhang, Shiyue Zhou, Linjie Han, Qunying Zhang, and Wayne Pritts are employees of AbbVie Inc. Funding This work was supported by the AbbVie.  ... 
doi:10.1080/19420862.2019.1628589 pmid:31238787 pmcid:PMC6748606 fatcat:jq44tadwyvgcrmlnowtwxih2gm

Aeromagnetic Compensation Algorithm Based on Principal Component Analysis

Peilin Wu, Qunying Zhang, Luzhao Chen, Wanhua Zhu, Guangyou Fang
2018 Journal of Sensors  
Aeromagnetic exploration is an important exploration method in geophysics. The data is typically measured by optically pumped magnetometer mounted on an aircraft. But any aircraft produces significant levels of magnetic interference. Therefore, aeromagnetic compensation is important in aeromagnetic exploration. However, multicollinearity of the aeromagnetic compensation model degrades the performance of the compensation. To address this issue, a novel aeromagnetic compensation method based on
more » ... incipal component analysis is proposed. Using the algorithm, the correlation in the feature matrix is eliminated and the principal components are using to construct the hyperplane to compensate the platform-generated magnetic fields. The algorithm was tested using a helicopter, and the obtained improvement ratio is 9.86. The compensated quality is almost the same or slightly better than the ridge regression. The validity of the proposed method was experimentally demonstrated.
doi:10.1155/2018/5798287 fatcat:xf5dz6axjvfvzmoztpbydic7sy

Finding normal bases over finite fields with prescribed trace self-orthogonal relations [article]

Xiyong Zhang and Rongquan Feng and Qunying Liao and Xuhong Gao
2013 arXiv   pre-print
Normal bases and self-dual normal bases over finite fields have been found to be very useful in many fast arithmetic computations. It is well-known that there exists a self-dual normal basis of F_2^n over F_2 if and only if 4∤ n. In this paper, we prove there exists a normal element α of F_2^n over F_2 corresponding to a prescribed vector a=(a_0,a_1,...,a_n-1)∈F_2^n such that a_i=Tr_2^n|2(α^1+2^i) for 0≤ i≤ n-1, where n is a 2-power or odd, if and only if the given vector a is symmetric
more » ... -i for all i, 1≤ i≤ n-1), and one of the following is true. 1) n=2^s≥ 4, a_0=1, a_n/2=0, ∑_1≤ i≤ n/2-1, (i,2)=1a_i=1; 2) n is odd, (∑_0≤ i≤ n-1a_ix^i,x^n-1)=1. Furthermore we give an algorithm to obtain normal elements corresponding to prescribed vectors in the above two cases. For a general positive integer n with 4|n, some necessary conditions for a vector to be the corresponding vector of a normal element of F_2^n over F_2 are given. And for all n with 4|n, we prove that there exists a normal element of F_2^n over F_2 such that the Hamming weight of its corresponding vector is 3, which is the lowest possible Hamming weight.
arXiv:1303.2283v1 fatcat:4kh5b2pwjnd23jeqtl53mu5mey

Investigation on a Novel Capacitive Electrode for Geophysical Surveys

Zhiyu Wang, Shun Wang, Guangyou Fang, Qunying Zhang
2016 Journal of Sensors  
Nonpolarizable electrodes are applied widely in the electric field measurement for geophysical surveys. However, there are two major problems: (1) systematic errors caused by poor electrical contact in the high resistive terrains and (2) environmental damage associated with using nonpolarizable electrodes. A new alternative structure of capacitive electrode, which is capable of sensing surface potential through weak capacitive coupling, is presented to solve the above problems. A technique is
more » ... troduced to neutralize distributed capacitance and input capacitance of the detection circuit. With the capacitance neutralization technique, the transmission coefficient of capacitive electrode remains stable when environmental conditions change. The simulation and field test results indicate that the new capacitive electrode has an operating bandwidth range from 0.1 Hz to 1 kHz. The capacitive electrodes have a good prospect of the applications in geophysical prospecting, especially in resistive terrains.
doi:10.1155/2016/4209850 fatcat:lzeiigvzvjau5j2ovs7rbdwo7q

Association of LIN28B polymorphisms with chronic hepatitis B virus infection

Qunying Han, Jiao Sang, Xiude Fan, Xiaoyun Wang, Lu Zeng, Xiaoge Zhang, Kun Zhang, Na Li, Yi Lv, Zhengwen Liu
2020 Virology Journal  
LIN28B is involved in multiple cellular developmental processes, tissue inflammatory response and tumourigenesis. The association of LIN28B polymorphisms with hepatitis B virus (HBV) infection remains unknown. This study investigated the association of LIN28B rs314277, rs314280, rs369065 and rs7759938 polymorphisms in patients with chronic HBV infection, a major cause of liver disease including hepatocellular carcinoma (HCC). A total of 781 individuals including 515 cases of chronic HBV
more » ... n (91 asymptomatic carrier status, 128 chronic hepatitis, 127 cirrhosis and 169 HCC), 97 HBV infection resolvers and 169 healthy controls were investigated. LIN28 rs314280 genotypes GA + AA were higher in resolver and controls than patients (P = 0.011). Patients had significantly lower rs314280 allele A than resolvers (P = 0.031, OR 0.689, 95%CI 0.491-0.969) or controls (P = 0.034, OR 0.741, 95%CI 0.561-0.978). In dominant model, patients had significantly lower rs314280 genotypes AA+GA than controls (P = 0.008, OR 0.623, 95%CI 0.439-0.884). LIN28 rs7759938 genotypes TC + CC were higher in resolvers and controls than patients (P = 0.015). Patients had significantly lower rs7759938 allele C than resolvers (P = 0.048, OR 0.708, 95%CI 0.503-0.999). In dominant model, patients had significantly lower rs7759938 genotypes TC + CC than controls (P = 0.010, OR 0.632, 95%CI 0.445-0.897). Chronic hepatitis patients had lower frequency of rs369065 genotype TC than asymptomatic carriers, cirrhosis and HCC (P = 0.019). These results suggest that LIN28 rs314280 and rs7759938 may be related to the susceptibility of chronic HBV infection. Further studies are warranted to examine the association of LIN28B polymorphisms with HBV-related diseases, especially HCC.
doi:10.1186/s12985-020-01353-7 pmid:32571380 fatcat:wd7wwsxtsrgjjena5mvqribl5q

Modified Biogeography-Based Optimization with Local Search Mechanism

Quanxi Feng, Sanyang Liu, Qunying Wu, GuoQiang Tang, Haomin Zhang, Huazhou Chen
2013 Journal of Applied Mathematics  
Biogeography-based optimization (BBO) is a new effective population optimization algorithm based on the biogeography theory with inherently insufficient exploration capability. To address this limitation, we proposed a modified BBO with local search mechanism (denoted as MLBBO). In MLBBO, a modified migration operator is integrated into BBO, which can adopt more information from other habitats, to enhance the exploration ability. Then, a local search mechanism is used in BBO to supplement with
more » ... odified migration operator. Extensive experimental tests are conducted on 27 benchmark functions to show the effectiveness of the proposed algorithm. The simulation results have been compared with original BBO, DE, improved BBO algorithms, and other evolutionary algorithms. Finally, the performance of the modified migration operator and local search mechanism are also discussed.
doi:10.1155/2013/960524 fatcat:4xtqpm2csze4zag7xrxplaw74m

Development of a sandwich ELISA for the quantification of enterovirus 71

Shujun Ma, Qunying Mao, Zhenglun Liang, Cuijuan Zhang, Wenxing Yang, Zhe Sun, Haijiang Zhang, Xinliang Shen, Shengli Bi, Le Sun
2013 Cytotechnology (Dordrecht)  
Since 2008, enterovirus 71 (EV71) has been responsible for high-mortality seasonal epidemics of hand, foot and mouth disease in China. Currently many groups in the world are in the process of developing EV71 vaccines to combat this deadly disease. We have developed three EV71-specific monoclonal antibodies, and in this study we report the establishment of a fast and cost-effective sandwich ELISA kit for measurement of virus concentration in EV71 vaccines using a pair of mouse anti-EV71
more » ... l antibodies. The system is specific for EV71 virus, with no cross-reactivity to coxsackievirus A16, H1N1, rabies, and hepatitis A. Using a reference EV71 vaccine standard, the sensitivity of the assay kit was determined to be 0.82 U/ml, with a linear range between 3.75 and 120 U/ml.
doi:10.1007/s10616-013-9588-9 pmid:23728855 pmcid:PMC3973802 fatcat:7odwnhsegvdghkz47crqpg4ari

Novel Fault Location Method for Power Systems Based on Attention Mechanism and Double Structure GRU Neural Network

Fan Zhang, Qunying Liu, Yilu Liu, Ning Tong, Shuheng Chen, Changhua Zhang
2020 IEEE Access  
FAN ZHANG received the B.S. degree in automation from Tiangong University, Tianjin, China, in 2018.  ...  QUNYING LIU (Member, IEEE) received the B.Eng., M.S., and Ph.D. degrees in electrical engineering from Sichuan University, Chengdu, China, in 2000, 2005, and 2008, respectively.  ... 
doi:10.1109/access.2020.2988909 fatcat:ebmtazyss5gkdfk3urldkkzhry

PI3K/AKT inhibition in tumor propagating cells of DLBCL reverses R-CHOP resistance by destabilizing SOX2 [article]

Jianfeng Chen, Xiaowen Ge, Wei Zhang, Peipei Ding, Yiqun Du, Qi Wang, Ling Li, Lan Fang, Yujing Sun, Pingzhao Zhang, Yuzhen Zhou, Long Zhang (+9 others)
2019 bioRxiv   pre-print
We thank Ping Zhang and Yuhu Xin for technical support. Finally, we thank the DLBCL patients and their family members for supporting our research.  ... 
doi:10.1101/657445 fatcat:gpolysbsjnbsphblqt6sjweu5a

AMPK-autophagy inhibition sensitizes icaritin-induced anti-colorectal cancer cell activity

Chunxian Zhou, Jun Gu, Gang Zhang, Da Dong, Qunying Yang, Min-Bin Chen, Dongfeng Xu
2017 OncoTarget  
The current research studied the potential effect of autophagy on icaritin-induced anti-colorectal cancer (CRC) cell activity. Treatment of icaritin in both primary and established (HT-29) CRC cells induced feedback activation of autophagy, evidenced by p62 degradation, Beclin-1 and autophagy-related gene-5 (ATG-5) upregulation, as well as light chain 3B (LC3B)-GFP puncta formation. Pharmacological inhibiting of autophagy dramatically potentiated icaritin-induced CRC cell death and apoptosis.
more » ... anwhile, shRNA-mediated knockdown of Beclin-1 or ATG-5 also sensitized icaritininduced CRC cell death and apoptosis. Icaritin activated AMP-activated protein kinase (AMPK) signaling in CRC cells, functioning as the upstream signaling for autophagy activation. shRNA/siRNA-mediated knockdown of AMPKα1inhibited icaritin-induced autophagy activation, but exacerbated CRC cell death. On the other hand, the AMPK activator compound 13 (C13) or the autophagy activator MHY1485 attenuated icaritininduced cytotoxicity. In nude mice, icaritin (oral administration)-induced HT-29 tumor growth inhibition was potentiated when combined with AMPKα1 shRNA knockdown in tumors. We conclude that feedback activation of AMPK-autophagy pathway could be a primary resistance factor of icaritin.
doi:10.18632/oncotarget.14718 pmid:28103582 pmcid:PMC5362439 fatcat:l7m4zkbalbfn7p24iwi5enxcwm
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