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.

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

Fermentation of purple Jerusalem artichoke extract to improve the α-glucosidase inhibitory effect in vitro and ameliorate blood glucose in db/db mice

Zhiqiang Wang,Seung Hwan Hwang,Sun Youb Lee,Soon Sung Lim 대한지역사회영양학회 2016 Nutrition Research and Practice Vol.10 No.3

BACKGROUND/OBJECTIVES: Jerusalem artichoke has inhibitory activity against α-glucosidase and decreases fasting serum glucose levels, which may be related to its fructan content. The biological activity of fructan can be influenced by the degree of polymerization. Thus, in this study, the inhibitory effects of original and fermented purple Jerusalem artichoke (PJA) on α-glucosidase were compared in vitro. Additionally, the anti-diabetes effect of Lactobacillus plantarum-fermented PJA (LJA) was studied in a non-insulin-dependent diabetes mellitus animal model (C57BIKsJ db/db). MATERIALS/METHODS: The water extract of PJA was fermented by L. plantarum, and two strains of Bacillus subtilis to compare their anti-α-glucosidase activities in vitro by α-glucosidase assays. The anti-diabetes effect of LJA was studied in a non-insulin-dependent diabetes mellitus animal model (C57BIKsJ db/db) for seven weeks. During the experiment, food intake, body weight, and fasting blood glucose were measured every week. At the end of the treatment period, several diabetic parameters and the intestinal α-glucosidase activity were measured. RESULTS: The LJA showed the highest α-glucosidase inhibitory activity in vitro. In the in vivo study, it resulted in a significantly lower blood glucose concentration than the control. Serum insulin and HDL cholesterol levels were significantly higher and the concentrations of triglycerides, non-esterified fatty acids, and total cholesterol were significant lower in mice treated with LJA after seven weeks. In addition, the intestinal α-glucosidase activity was partially inhibited. CONCLUSIONS: These results suggested that LJA regulates blood glucose and has potential use as a dietary supplement.

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.

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.

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.

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.

Pistafolin B is the major aldose reductase inhibitor of the pods of tara [<i>Caesalpinia spinose</i> (Molina) Kuntze]

Wang, Zhiqiang,Guillen Quispe, Yanymee N.,Hwang, Seung Hwan,Zuo, Guanglei,Lim, Soon Sung Elsevier 2018 Industrial crops and products Vol.122 No.-

<P><B>Abstract</B></P> <P>Aldose reductase, the pivotal enzyme in the polyol pathway, has been widely investigated as an enzyme critically involved in the onset and progression of various pathologies associated with diabetes mellitus. Investigation of the inhibitory effect of tara [<I>Caesalpinia spinosa</I> (Molina) Kuntze] pods extract on aldose reductase revealed that its <I>n</I>-butanol fraction exhibits excellent aldose reductase inhibitory activity <I>in vitro</I> and <I>ex vivo</I>. Methyl gallate and pistafolin B were isolated from the <I>n</I>-butanol fraction of the tara pod methanolic extract as the main contributors for its aldose reductase inhibition, guided by affinity-based ultrafiltration-high performance liquid chromatography, with pistafolin B being the more potent inhibitor of the two. <I>In vitro</I> and <I>in silico</I> results demonstrated that pistafolin B is a mixed-type inhibitor that can bind to the aldose reductase active site rapidly, preventing substrate access and product formation (IC<SUB>50</SUB>, 0.198 mM; <I>K</I> <SUB>i</SUB>, 0.34 mM). <I>Ex vivo</I> experiments indicated that pistafolin B can penetrate the eye lens and successfully inhibit aldose reductase under hyperglycaemic conditions, thus preventing the accumulation of sorbitol and the subsequent osmotic stress.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The inhibitory effects of tara pods on aldose reductase activity were investigated. </LI> <LI> <I>n</I>-Butanol fraction of tara pods extract showed best aldose reductase inhibition. </LI> <LI> Aldose reductase ultrafiltration-high pressure liquid chromatography was developed. </LI> <LI> Pistafolin B was identified as a novel aldose reductase inhibitor in tara pods. </LI> </UL> </P>

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

An Optimized Third Harmonic Injection Method for Three-Phase Cascaded H-Bridge Photovoltaic Inverter

Wang Mao,Xing Zhang,Tao Zhao,Yuhua Hu,Fusheng Wang,Zhiqiang Dai,Renxian Cao 전력전자학회 2019 ICPE(ISPE)논문집 Vol.2019 No.5

The uneven irradiation and temperature in photovoltaic (PV) modules of three-phase cascaded H-bridge (CHB) inverters will cause the unbalanced output power between solar panels, resulting in unbalanced grid current between three phases. In addition, since each phase can be regarded as a single-phase inverter, the second harmonic voltage pulsation of dc-side capacitors is a problem to be solved. To solve these two problems, a third harmonic injection optimization method on the basis of fundamental frequency zero sequence is proposed in this paper. The third harmonic with the same amplitude of fundamental modulated wave signal is injected into the modulated wave signal when the amplitude of synthesized wave signal is no greater than unity. Otherwise, the amplitude of third harmonic is decreased correspondingly to ensure the amplitude of synthesized wave signal being unity. With this method, the dc-side voltage pulsation is effectively restrained and the power balancing limit of CHB inverter is expanded. The feasibility and effectiveness of this method are verified by an experimental prototype of a three-phase seven-level CHB inverter.