Research on the Inter-harmonics Equivalent Impedance of Series Hybrid Active Power Filter

Jian-gong, Zhang,Jian-ben, Liu,Shao-jun, Dai,Qiao-fu, Chen,Jun-jia, He The Korean Institute of Electrical Engineers 2015 Journal of Electrical Engineering & Technology Vol.10 No.5

In the series hybrid active power filter (SHAPF) with magnetic flux compensation (MFC), the system current oscillate in the experimental results when adding the same phase harmonic current command in current control block. This condition endangers the security of the SHAPF. Taking the digit period average arithmetic as example, this paper explains the inter-harmonics current oscillation in the experiment. The conclusion is that the SHAPF is unstable to the inter-harmonics current in theory. Limited by the capacity of the inverter, the system current and the inverter output current do not increase to infinite. At last, some methods are proposed to solve this problem. From the practical viewpoint, the voltage feed-forward control is easy to achieve. It can suppress the current oscillation problems, and also improve the filtering effect. The feasibility of the methods is validated by both the emulation and experiment results.

Research on the Inter-harmonics Equivalent Impedance of Series Hybrid Active Power Filter

Zhang Jian-gong,Liu Jian-ben,Dai Shao-jun,Chen Qiao-fu,He Jun-jia 대한전기학회 2015 Journal of Electrical Engineering & Technology Vol.10 No.5

In the series hybrid active power filter (SHAPF) with magnetic flux compensation (MFC), the system current oscillate in the experimental results when adding the same phase harmonic current command in current control block. This condition endangers the security of the SHAPF. Taking the digit period average arithmetic as example, this paper explains the inter-harmonics current oscillation in the experiment. The conclusion is that the SHAPF is unstable to the inter-harmonics current in theory. Limited by the capacity of the inverter, the system current and the inverter output current do not increase to infinite. At last, some methods are proposed to solve this problem. From the practical viewpoint, the voltage feed-forward control is easy to achieve. It can suppress the current oscillation problems, and also improve the filtering effect. The feasibility of the methods is validated by both the emulation and experiment results.

An Effective Guidewire Looping Technique for the Recanalization of Occlusive Segments of Infrapopliteal Vessels

Jian-bo Wang,Jun-gong Zhao,Ming-hua Li,Yue-qi Zhu,Jue Wang,Pei-lei Zhang 대한영상의학회 2010 Korean Journal of Radiology Vol.11 No.4

Objective: To determine the efficacy, safety and primary follow-up results of a guidewire looping technique for the treatment of infrapopliteal arteries. Materials and Methods: From October 2006 to May 2008, an intraluminal angioplasty of the infrapopliteal arteries was attempted in 200 consecutive patients. Altogether, 417 infrapopliteal lesions, with lengths varying from 2 cm to 32 cm, were treated as part of this study, including 305 lesions in the anterior tibial arteries, 89 in the posterior tibial arteries, and 23 in the peroneal arteries. The ‘U’-shaped guidewire technique was attempted in 393 lesions from 361 limbs. The tip of a hydrophilic 0.035-inch guidewire was formed into a ‘U’ shape with the aid of a 4-Fr catheter and collateral branch vessel to recanalize the completely occluded long segment lesions. Results: A successful angioplasty with at least one artery recanalized directly to the malleolar or dorsal foot was achieved in 322 limbs (89%). The looping technique had a success rate of 90% (352 of 393 lesions). After the procedure, the rest pain was relieved in 58 of 69 patients, while 207 of 245 limbs (85%) showed improvement for intermittent claudication. Complete wound healing was noted in 21 of 54 patients, while 20 of 54 patients showed an improvement in the wound size or depth. A total of 38 major immediate procedure-related complications were noted, including retroperitoneal hematoma, distal emboli, and vessel rupture. Conclusion: The results of this study suggests that the guidewire looping technique is a safe and effective method for the recanalization of the occluded lesions in infrapopliteal vessels. Objective: To determine the efficacy, safety and primary follow-up results of a guidewire looping technique for the treatment of infrapopliteal arteries. Materials and Methods: From October 2006 to May 2008, an intraluminal angioplasty of the infrapopliteal arteries was attempted in 200 consecutive patients. Altogether, 417 infrapopliteal lesions, with lengths varying from 2 cm to 32 cm, were treated as part of this study, including 305 lesions in the anterior tibial arteries, 89 in the posterior tibial arteries, and 23 in the peroneal arteries. The ‘U’-shaped guidewire technique was attempted in 393 lesions from 361 limbs. The tip of a hydrophilic 0.035-inch guidewire was formed into a ‘U’ shape with the aid of a 4-Fr catheter and collateral branch vessel to recanalize the completely occluded long segment lesions. Results: A successful angioplasty with at least one artery recanalized directly to the malleolar or dorsal foot was achieved in 322 limbs (89%). The looping technique had a success rate of 90% (352 of 393 lesions). After the procedure, the rest pain was relieved in 58 of 69 patients, while 207 of 245 limbs (85%) showed improvement for intermittent claudication. Complete wound healing was noted in 21 of 54 patients, while 20 of 54 patients showed an improvement in the wound size or depth. A total of 38 major immediate procedure-related complications were noted, including retroperitoneal hematoma, distal emboli, and vessel rupture. Conclusion: The results of this study suggests that the guidewire looping technique is a safe and effective method for the recanalization of the occluded lesions in infrapopliteal vessels.

Antifibrotic Effect of Curcumin in TGF-β1-Induced Myofibroblasts from Human Oral Mucosa

Zhang, Shan-Shan,Gong, Zhao-Jian,Li, Wen-Hui,Wang, Xiao,Ling, Tian-You Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.1

Background: Myofibroblasts play an important role in the development of oral submucous fibrosis (OSF). In the current study, we investigate the effect of curcumin on growth and apoptosis of myofibroblasts derived from human oral mucosa. Methods: Myofibroblasts were generated by incubating fibroblasts, obtained from human oral mucosa, with transforming growth factor-${\beta}1$ (TGF-${\beta}1$). MTT, PI staining, and FACS assays were used to investigate curcumin's effect on proliferation and cell cycle of fibroblasts and myofibroblasts. Annexin V/PI binding and FACS assays were used to examine apoptosis of myofibroblasts, Western blotting to determine the levels of Bcl-2 and Bax, and enzyme-linked immunosorbant assay was employed to examine the levels of collagen type I and III in the supernatants of myofibroblasts. Results: Curcumin inhibits proliferation of fibroblasts and myofibroblasts; it also disturbs the cell cycle, induces apoptosis and decreases the generation of collagen type I and III in myofibroblasts, which are more sensitive to its effects than fibroblasts. Curcumin induces apoptosis in myofibroblasts by down-regulating the Bcl-2/ Bax ratio. Conclusion: Our results demonstrate the antifibrotic effect of curcumin in vitro. It may therefore be a candidate for the treatment of OSF.

FolkRank++: An Optimization of FolkRank Tag Recommendation Algorithm Integrating User and Item Information

( Jianli Zhao ),( Qinzhi Zhang ),( Qiuxia Sun ),( Huan Huo ),( Yu Xiao ),( Maoguo Gong ) 한국인터넷정보학회 2021 KSII Transactions on Internet and Information Syst Vol.15 No.1

The graph-based tag recommendation algorithm FolkRank can effectively utilize the relationships between three entities, namely users, items and tags, and achieve better tag recommendation performance. However, FolkRank does not consider the internal relationships of user-user, item-item and tag-tag. This leads to the failure of FolkRank to effectively map the tagging behavior which contains user neighbors and item neighbors to a tripartite graph. For item-item relationships, we can dig out items that are very similar to the target item, even though the target item may not have a strong connection to these similar items in the user-item-tag graph of FolkRank. Hence this paper proposes an improved FolkRank algorithm named FolkRank++, which fully considers the user-user and item-item internal relationships in tag recommendation by adding the correlation information between users or items. Based on the traditional FolkRank algorithm, an initial weight is also given to target user and target item's neighbors to supply the user-user and item-item relationships. The above work is mainly completed from two aspects: (1) Finding items similar to target item according to the attribute information, and obtaining similar users of the target user according to the history behavior of the user tagging items. (2) Calculating the weighted degree of items and users to evaluate their importance, then assigning initial weights to similar items and users. Experimental results show that this method has better recommendation performance.

Improved Algorithm for Image Segmentation based on the Three-dimensional Reconstruction of Tumor Images

Jianning Han,Quan Zhang,Peng Yang,Yifan Gong 보안공학연구지원센터 2015 International Journal of Signal Processing, Image Vol.8 No.6

High Resolution Photoacoustic System Based on Acoustic Lens with Negative Refractive Index

Jianning Han,Quan Zhang,Peng Yang,Yifan Gong 보안공학연구지원센터 2015 International Journal of Signal Processing, Image Vol.8 No.4

Diagnostic value of Contrast-Enhanced Ultrasound Parametric Imaging in Breast Tumors

Zhang Yuan,Jiang Quan,Zhang Yunxiao,Chen Jian,He Zhu,Gong Liping 한국유방암학회 2013 Journal of breast cancer Vol.16 No.2

Purpose: This study aimed to evaluate the diagnostic value of SonoLiver software for parametric imaging in breast tumors. Methods: Contrast-enhanced ultrasound (CEUS) was performed in 216 breast lesions (113 malignant, 103 benign). The CEUS parameters were compared between benign and malignant lesions. The rise time, the time to peak, the mean transit time and dynamic vessel pattern (DVP) were analyzed using SonoLiver software. Results: Quantitative analysis showed that the rise time was 16.52±4.15 seconds in the benign group vs. 13.86±3.36 seconds in the malignant group (p=0.007), and the time to peak was 19.86±4.87 seconds in the benign group vs. 16.52±4.85 seconds in the malignant group (p=0.009). The mean transit time was 80.55±18.65 seconds in the benign group vs. 65.16±20.28 seconds in the malignant group (p=0.006). The difference between the distribution of DVP in benign and malignant tumors was statistically significant. One hundred one malignant tumors (89.4%) performed an irregular red/yellow fill in the region of interest (ROI) and 85 benign tumors (82.5%) performed a single blue/green fill in the ROI. The sensitivity, specificity, and accuracy of parametric imaging in breast tumors were 84.1%, 85.4%, 84.7%, respectively. Conclusion: The CEUS parametric imaging can distinguish differences between malignant and benign breast tumors as well as provide diagnostic information on breast lesions.

Functional Components of Bamboo Shavings and Bamboo Leaf Extracts and Their Antioxidant Activities In Vitro

Jinyan Gong,Dao-Zong Xia,Jun Huang,Qing Ge,Jian-wei Mao,Shiwang Liu,Ying Zhang 한국식품영양과학회 2015 Journal of medicinal food Vol.18 No.4

This study was designed to detect characteristic compounds and evaluate the free radical scavenging capacity of the bamboo leaves extract and bamboo shavings extract (BSE). The antioxidant capacity of bamboo leaf n-butanol fraction (AOB) exhibited the highest total phenolic content (49.93%), total flavonoids content (24.11%), and characteristic flavonoids and phenolic acids, such as chlorogenic acid, caffeic acid, ferulic acid, p-coumaric acid, orientin, homoorientin, vitexin, and isovitexin. Available data obtained with in vitro models suggested that AOB had higher free radical scavenging capacity with IC50 values of 1.04, 4.48, 5.37, and 1.12 μg/mL on DPPH•, O2•- , •OH, and H2O2, respectively, than the other two extracts, bamboo leaf water extract and BSE. The results indicated that the extracts from different parts of the bamboo possess excellent antioxidant activity, which can be used potentially as a readily accessible and valuable bioactive source of natural antioxidants.

Loofah sponge activated by periodate oxidation as a carrier for covalent immobilization of lipase

Renmin Gong,Jian Zhang,Jun Zhu,Jianting Wang,Qiumei Lai,Bo Jiang 한국화학공학회 2013 Korean Journal of Chemical Engineering Vol.30 No.8

Cellulose in loofah sponge was first oxidized by sodium periodate at positions 2 and 3 of anhydroglucose unit to introduce aldehyde groups, which were able to react with amino groups of lipase to form Schiff’s base, and result in loofah sponge immobilized lipase. The result of periodate oxidation was confirmed by determination of aldehyde group content and analysis of Fourier transform infrared spectra. The optimal pH for both free and immobilized lipases was approximately 7.5. The maximum activity of immobilized lipase was observed at 40 oC, while the free lipase exhibited maximum activity at 37 oC. The immobilized lipase presented improved thermal stability, storage stability, and reusability.