Image Edge Detection Based on Anti-Symmetrical Biorthogonal Wavelet Filter Banks with the Same Even Length

Xiaoyan Wang,Baochen Jiang,Chengyou Wang,Zhiqiang Yang,Xiaoyan Wang 보안공학연구지원센터 2014 International Journal of Signal Processing, Image Vol.7 No.5

With the development of the theory of wavelet transform, biorthogonal wavelet filter banks with linear phase and compact support characteristics are widely used in signal and image processing. We study the multiscale edge detection using anti-symmetrical biorthogonal wavelet filter banks with the same even length based on the analysis of the properties of this wavelet filter banks. The steps of multiscale edge detection based on anti-symmetrical biorthogonal wavelet are introduced in detail. Experimental results on test images show that compared with the anti-symmetrical biorthogonal wavelet, the proposed anti-symmetrical biorthogonal wavelet filter banks with the same even length have better performance in terms of image edge detection. Therefore, the anti-symmetrical biorthogonal wavelet filter banks with the same even length are more suitable for image edge detection.

Seismic Response Analysis of Self-anchored Suspension Bridge with Multi-tower

Zhiqiang Wang,Wei Xiao,Hongyi Wei 한국강구조학회 2016 International Journal of Steel Structures Vol.16 No.4

Seismic performance of a self-anchored suspension bridge with three-tower were investigated. A three-dimensional nonlinear finite element model of the bridge was developed using Sap2000. Nonlinear time history analysis was conducted using Fast Nonlinear Analysis Method (FNA), while beam-column effect and nonlinear behavior of bearing and damper were taken into consideration. The analyze results showed that the middle tower was more vulnerable compared with the two side towers; there existed risk of buckling of composite beam, and the most vulnerable part lied near steel-concrete composite segment. Viscous dampers were effective to reduce seismic response of towers as well as girders.

Advances in CRISPR-Cas systems for RNA targeting, tracking and editing

Wang, Fei,Wang, Lianrong,Zou, Xuan,Duan, Suling,Li, Zhiqiang,Deng, Zixin,Luo, Jie,Lee, Sang Yup,Chen, Shi Elsevier 2019 BIOTECHNOLOGY ADVANCES Vol.37 No.5

<P><B>Abstract</B></P> <P>Clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated protein (Cas) systems, especially type II (Cas9) systems, have been widely used in gene/genome targeting. Modifications of Cas9 enable these systems to become platforms for precise DNA manipulations. However, the utilization of CRISPR-Cas systems in RNA targeting remains preliminary. The discovery of type VI CRISPR-Cas systems (Cas13) shed light on RNA-guided RNA targeting. Cas13d, the smallest Cas13 protein, with a length of only ~930 amino acids, is a promising platform for RNA targeting compatible with viral delivery systems. Much effort has also been made to develop Cas9, Cas13a and Cas13b applications for RNA-guided RNA targeting. The discovery of new RNA-targeting CRISPR-Cas systems as well as the development of RNA-targeting platforms with Cas9 and Cas13 will promote RNA-targeting technology substantially. Here, we review new advances in RNA-targeting CRISPR-Cas systems as well as advances in applications of these systems in RNA targeting, tracking and editing. We also compare these Cas protein-based technologies with traditional technologies for RNA targeting, tracking and editing. Finally, we discuss remaining questions and prospects for the future.</P> <P><B>Highlights</B></P> <P> <UL> <LI> RNA targeting and editing are becoming increasingly important </LI> <LI> CRISPR-Cas systems are advancing for RNA targeting, tracking and editing </LI> <LI> The type VI CRISPR-Cas systems are useful for RNA-guided RNA targeting </LI> <LI> Use of Cas9 and Cas13 will advance RNA-targeting technologies </LI> </UL> </P>

A New Three-Phase Current Modulation Method to Suppress the Commutation Torque Ripple of Brushless DC Motor

Wang, Zhiqiang,Yin, Shuai,Ma, Tiehua The Korean Institute of Electrical Engineers 2017 Journal of Electrical Engineering & Technology Vol.12 No.5

The brushless DC motor's commutation torque ripple is caused by inconsistency in the rate of phase current change. Thus, a method that considers armature resistance is proposed to modulate phase current. The three-phase control strategy, which involves the "open-phase conduction, off-phase pulse width modulation, and maintained non-commutation phase" technique, is applied during commutation at full-speed segments of the motor. Changes in each phase current are analyzed theoretically by establishing mathematical model based on phase current to determine the relative difference among shutdown phase, duty, and motor operating parameters. The turn-on and turn-off phase current change rates are made to be consistent to ensure less non-commutation phase current ripple, then the torque ripple is inhibited. The simulation results show that the phase commutation current and torque ripple coefficient of the proposed method are reduced from 56.9% and 55.5% to 6.8% and 6.1%, respectively. In the experiment system, the pulsation coefficient of the motor phase current is reduced from 40.0% to 16.7% at low speed and 50.0% to 18.8% at high speed. The simulation and experimental results show that the proposed control method significantly inhibits commutation current and torque in the full section.

Observer-based Finite-time Model Reference Adaptive State Tracking Control with Actuator Saturation

Zhiqiang Wang,Dakuo He,Qiang Zhang,Jiahui Shi 제어·로봇·시스템학회 2020 International Journal of Control, Automation, and Vol.18 No.11

In this paper, the problem of finite-time model reference adaptive state tracking control and the weighted H∞ performance are studied with state unmeasured and actuator saturation. Compared with the existing literature, the state directly measurable problem is relaxed through a state observer. A model reference based adaptive controller is designed to address the state tracking error. Considering the disdifferentiability of the state for the considered system when the controller is saturated, an auxiliary design function is proposed to solve this problem. By utilizing Lyapunov stability theorem, finite-time tracking error bounded and the finite-time weighted H∞ performance are investigated. Moreover, the conservatism of the considered system is investigated by defining the different saturation rates. Finally, examples are provided as a means of illustrating the effective design method.

Color Image Coding Based on Shape-Adaptive All Phase Biorthogonal Transform

Wang, Xiaoyan,Wang, Chengyou,Zhou, Xiao,Yang, Zhiqiang Korea Information Processing Society 2017 Journal of information processing systems Vol.13 No.1

This paper proposes a color image coding algorithm based on shape-adaptive all phase biorthogonal transform (SA-APBT). This algorithm is implemented through four procedures: color space conversion, image segmentation, shape coding, and texture coding. Region-of-interest (ROI) and background area are obtained by image segmentation. Shape coding uses chain code. The texture coding of the ROI is prior to the background area. SA-APBT and uniform quantization are adopted in texture coding. Compared with the color image coding algorithm based on shape-adaptive discrete cosine transform (SA-DCT) at the same bit rates, experimental results on test color images reveal that the objective quality and subjective effects of the reconstructed images using the proposed algorithm are better, especially at low bit rates. Moreover, the complexity of the proposed algorithm is reduced because of uniform quantization.

Identifying Key Factors Affecting Information Disclosure Intention in Online Shopping

Zhiqiang Wang,Yanjun Liu 보안공학연구지원센터 2014 International Journal of Smart Home Vol.8 No.4

Blood lipids and all-cause mortality among old people: the Chinese Longitudinal Healthy Longevity Survey 2008-2018

Wang Rongxi,Yu Xiaoyue,Wang Zhiqiang,Liu Yujie,Chen Hui,Liu Shangbin,XU CHENG,Chen Yingjie,Xia Danni,Ge Xin,Chang Ruijie,Xu Gang,Xiang Mi,Wang Ying,Shen Tian,Hu Fan,Cai Yong 한국역학회 2022 Epidemiology and Health Vol.44 No.-

OBJECTIVES: Proper blood lipid levels are essential for survival in older adults, but inconsistent relationships have been reported between blood lipids and all-cause mortality in the elderly. METHODS: This retrospective longitudinal study analyzed data from 1,067 Chinese older adults enrolled in the Chinese Longitudinal Healthy Longevity Survey collected in 2008 and followed up until death or December 31, 2018. The outcome was allcause mortality. Multivariate Cox regression analyses were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) with stratification by age (60-80, 80-100, or ≥ 100 years) for further analysis. The survival probability according to lipid profile quartiles was calculated using Kaplan-Meier curves and the log-rank test. RESULTS: The participants’ mean age was 84.84 years, and 57.0% were female. In total, 578 individuals died, and 277 were lost to follow-up. The mean total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) levels were higher among those who died than among those who survived. Participants in the second HDL-C quartile and the highest LDL-C and triglyceride (TG) quartiles had 28% higher, 23% lower, and 49% lower risks of all-cause mortality, respectively. After further adjustment, the associations remained except for HDL-C, and additional associations were observed between all-cause mortality and the third TC and LDL-C quartiles and the second TG quartile (HR, 1.44; 95% CI, 1.01 to 2.06; HR, 0.68; 95% CI, 0.49 to 0.94; HR, 0.79; 95% CI, 0.62 to 0.99, respectively). CONCLUSIONS: Older adults should maintain an LDL-C level of 1.91-2.47 mmol/L and a TG level of no less than 1.66 mmol/L.

Strategic Fit Issues in Information System Research : Concept, Operationalization and Future Directions

Zhiqiang Wang 보안공학연구지원센터 2014 International Journal of Hybrid Information Techno Vol.7 No.1

Rail corrugation characteristics in small radius curve section of Cologne-egg fasteners

Zhiqiang Wang,Zhenyu Lei 대한기계학회 2020 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.34 No.11

The typical passing frequencies of corrugation were obtained by analysing the measured corrugation data in small radius curve track with Cologne-egg fasteners. The threedimensional solid element model of track structure was established with the software ABAQUS, and modal analysis was carried out to determine the relationship between natural frequencies of track structure and passing frequencies of corrugation. By using the material wear model based on friction work theory, the frequency characteristics of corrugation and the development law of wear under different speeds were studied, and the control measures of corrugation were analysed. The new point of this study is to implement the above dynamic analysis from the perspective of vehicle (with flexible wheelsets) track space coupling, which can consider the coupled relationship in three directions of space. The results show that the generation of corrugation is closely related to the mechanical characteristics of track structure. Passing frequencies do not change with speeds, reflecting the frequency-fixing characteristics of corrugation. The analysis of control measures of corrugation shows that the smaller the friction coefficient is, the less likely the rail is to produce corrugation. The existence of rail vibration absorber can eliminate the generation of some short wavelength corrugation and reduce the rail bending vibration, which has a significant effect on the control of corrugation.