An Investigation of Surface Tracking Characteristics and Factors Influencing Epoxy Resin Pouring Insulation for Dry-type Reactors

Yongqiang Wang,Han Liu,Wenpeng Li,Renjie Ding 한국고분자학회 2019 Macromolecular Research Vol.27 No.3

This study aimed to understand the deterioration mechanisms of epoxy resin pouring insulation for outdoor dry-type reactors under the effect of long-term surface tracking discharge. Epoxy resin insulation boards similar to the main insulation composition of the dry-type reactor were poured as the experimental material. A tracking experimental platform of insulation materials was built using an inclined plate method. The tracking discharge characteristics and surface erosion of the insulation materials were measured and analyzed. The characteristics of partial discharge, erosion, hydrophobicity and surface roughness were measured experimentally. Surface morphology, three-dimensional morphology and Fourier infrared images at different stages during erosion of the epoxy resin insulation material were analyzed. The effect of glass fiber content on the tracking resistance to erosion was characterized. The results show that the tracking process of epoxy resin insulation material experienced initiation, stability, development and outbreak periods. The flashover discharge corresponding to the development period was the main reason for the carbonization of the insulating material. During the tracking process, with a change in surface topography and formation of surface products, the surface roughness of the material generally increased along with the surface roughness which rose fastest during the discharge outbreak period. The changes in the surface morphology and three-dimensional morphology of the epoxy resin material constitute the basis for assessing the condition of the insulation surface and development of the erosion. The discharge capacity of epoxy resin generally shows an exponential increase. Adding 20 wt% of glass fibers that are evenly distributed and have reduced exposure can improve the tracking resistance of epoxy resin insulation materials.

In vivo and in vitro evaluation of stability and antioxidant activity of lycopene-nanostructured lipid carriers

Yongqiang Ma,Chenchen Li,Weiye Xiu,Xin Wang 한국식품과학회 2023 Food Science and Biotechnology Vol.32 No.6

This study evaluates the stability of lycopene in the presence of the prepared nanostructured lipid carriers (NLCs) under different environments and food systems and the in vitro and in vivo antioxidant activity of the lycopene nanostructured lipid carriers (Lyco-NLCs) was studied. As observed in the stability experiment, Lyco-NLCs have good storage stability within 30 days. Food additives have little effect on its stability except for metal ions. Compared with free lycopene, Lyco-NLCs showed an improved antioxidant property. In in-vitro experiments, the DPPH radical scavenging rate, hydroxyl radical scavenging capacity, and ferric reducing capacity of Lyco-NLCs increased by 90.47%, 47.43%, and 45.12%, respectively. The animal experiments showed that the activities of catalase in the kidney, superoxide dismutase in the heart, and glutathione peroxidase in the liver increased by 31.48%, 42.50%, and 21.47%, respectively. The content of malondialdehyde in serum decreased by 14.13%. The results have some significance for the practical application of lycopene.

Research on Human Face Difference Imaging Based on Sparse Representation

Yongqiang Li 보안공학연구지원센터 2016 International Journal of Signal Processing, Image Vol.9 No.7

To make sure human face can be more accurately identified in various poses, an identification method based on the characteristics human face image have been proposed in the thesis. First, it is a design for the optimal sampling matrix to acquire compressed measurement data; then it adopts iterative method based on the close loops of l2 and l1 in normal form to get an estimate on human face images, since the method based on norm l2 can measure the relevancy of human face images in the space and time of the continuous time point, and the method based on norm l1 mainly uses the modified total variation method and basis pursuit noise-reduction method. The simulation design has suggested that the method adopted in the thesis can achieve a higher human face identification rate and a remarkable promotion effect.

Research of Product Design Optimization Based on Supporting Vector and Artificial Fish Swarm Algorithm

Yongqiang Li 보안공학연구지원센터 2016 International Journal of Hybrid Information Techno Vol.9 No.7

Exploration Analysis Based on Improved BP Neural Network in Human Body Movement

Yongqiang Li 보안공학연구지원센터 2016 International Journal of Multimedia and Ubiquitous Vol.11 No.7

Research on Model of College Network Rumor Propagation in the Era of Big Data

Yongqiang Zuo 보안공학연구지원센터 2016 International Journal of Database Theory and Appli Vol.9 No.11

Big Data consists of large-volume, complex, growing data sets with multiple, heterogenous sources. With the tremendous development of networking, data storage, and the data collection capacity, Big Data are now rapidly expanding in all science and engineering domains, including physical, biological and biomedical sciences. In the era of vigorous development network media, rumors propagation procedure becomes more complex, faster, and more dangerous. The identification and control of Internet rumors is important to related net-check departments. This paper establish an index system to evaluate the level of internet rumors and rumor credibility index system according to characteristics of rumor propagation, and analysis the advantages and disadvantages of the models through experimental verification.

A Compensated Software Reliability Model Based on Unascertained Rational Number

Yongqiang Zhang,Wen Chen,Huizhen Yan 한국멀티미디어학회 2006 한국멀티미디어학회 국제학술대회 Vol.2006 No.-

The software reliability model based on unascertained ration number has unique superiority. It does not have any assumption about software fault process. Moreover, its algorithm is simple, and it avoids derivation of nonlinear equations set. But the characteristic of the algorithm itself determines that the estimation of this model is the pessimistic estimation. In this view, this paper makes some improvement to this model, and puts forward the compensated software reliability model based on unascertained rational number, which make the model have wider applicability and suit the reliability growth feature better.

Influence of crack on the permeability of plastic concrete

Yongqiang He,Rayed Alyousef,Abdulaziz Alaskar,Hisham Alabduljabbar,Abdeliazim Mustafa Mohamed,Nelson Maureira-Carsalade,Angel Roco-Videla,Alibek Issakhov,Hamid Assilzadeh 국제구조공학회 2021 Smart Structures and Systems, An International Jou Vol.27 No.5

This study examined the relations between permeability of the concrete due to addition of new cracks. The different concrete types analyzed were standard concrete, reinforced steel fiber concrete, and reinforced concrete polypropylene fiber. In consideration of the improved polypropylene content of polypropylene fiber reinforced concrete, the crack diameter was decreased by 72-93% for up to 0.25% fiber and cracks were eliminated with 0.3% fiber inclusion. In terms of steel fiberreinforced concrete, the results showed that steel reinforcing macro fibers decrease the permeability of cracked concrete at wider crack widths. While the permeability of unreinforced concrete was the highest, 0.5% steel content resulted in lower permeability while a higher steel content concrete with 1% steel had the lowest permeability. Crack stitching phenomenon and the effect of multiple cracks may be attributed to the decrease in the permeability. With respect to normal concrete, the findings showed the crack opening displacement at the highest tension is less than 20 microns. At this loading stage, after unloading, around 80% of the displacement is restored and the residual crack opening is notably small, indicating the low impact of cracking on concrete permeability (CP) and showing that CP was increased with crack width. As a result, adding polypropylene aggregate to concrete could significantly reduce the width of crack, while adding steel fiber to concrete reduces the permeability of cracked concrete compared to normal concrete which may result in a minor crack on CP.

Research on Operating Performance and E-business Marketing Strategy in Retail Enterprises based on Online Shopping

Yongqiang Zhang,Yanlei Gao,Xiang Li,Duchun Wang 보안공학연구지원센터 2015 International Journal of Security and Its Applicat Vol.9 No.11

In recent years, with the rapid development of internet technology, enterprise business model has entered a new century. The emergence of network economy has forced retail enterprises to change the original marketing mode, global information resources can be shared instantly, which greatly improve the operational efficiency and reduce the cost. In this paper, we analyze the influence factors that impact on retail enterprises based on consumers online shopping behavior, survey data from small and medium enterprises. The result shows that macro environment factors, market competition, enterprise self factors will affect the enterprise's e-commerce performance, and significantly promote the enterprise's market strategy innovation. Therefore, it is an important way to improve the competitiveness of enterprises by carrying out the E-business market strategy.

Novel Robust High Dynamic Range Image Watermarking Algorithm Against Tone Mapping

( Yongqiang Bai ),( Gangyi Jiang ),( Hao Jiang ),( Mei Yu ),( Fen Chen ),( Zhongjie Zhu ) 한국인터넷정보학회 2018 KSII Transactions on Internet and Information Syst Vol.12 No.9

High dynamic range (HDR) images are becoming pervasive due to capturing or rendering of a wider range of luminance, but their special display equipment is difficult to be popularized because of high cost and technological problem. Thus, HDR images must be adapted to the conventional display devices by applying tone mapping (TM) operation, which puts forward higher requirements for intellectual property protection of HDR images. As the robustness presents regional diversity in the low dynamic range (LDR) watermarked image after TM, which is different from the traditional watermarking technologies, a concept of watermarking activity is defined and used to distinguish the essential distinction of watermarking between LDR image and HDR image in this paper. Then, a novel robust HDR image watermarking algorithm is proposed against TM operations. Firstly, based on the hybrid processing of redundant discrete wavelet transform and singular value decomposition, the watermark is embedded by modifying the structure information of the HDR image. Distinguished from LDR image watermarking, the high embedding strength can cause more obvious distortion in the high brightness regions of HDR image than the low brightness regions. Thus, a perceptual brightness mask with low complexity is designed to improve the imperceptibility further. Experimental results show that the proposed algorithm is robust to the existing TM operations, with taking into account the imperceptibility and embedded capacity, which is superior to the current state-of-art HDR image watermarking algorithms.