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      • SCIESCOPUSKCI등재

        A Novel Speed Estimation Method of Induction Motors Using Real-Time Adaptive Extended Kalman Filter

        Zhang, Yanqing,Yin, Zhonggang,Li, Guoyin,Liu, Jing,Tong, Xiangqian The Korean Institute of Electrical Engineers 2018 Journal of Electrical Engineering & Technology Vol.13 No.1

        To improve the performance of sensorless induction motor (IM) drives, a novel speed estimation method based on the real-time adaptive extended Kalman filter (RAEKF) is proposed in this paper. In this algorithm, the fuzzy factor is introduced to tune the measurement covariance matrix online by the degree of mismatch between the actual innovation and the theoretical. Simultaneously, the fuzzy factor can be continuously self-tuned tuned by the fuzzy logic reasoning system based on Takagi-Sugeno (T-S) model. Therefore, the proposed method improves the model adaptability to the actual systems and the environmental variations, and reduces the speed estimation error. Furthermore, a simple exponential function based on the fuzzy theory is used to reduce the computational burden, and the real-time performance of the system is improved. The correctness and the effectiveness of the proposed method are verified by the simulation and experimental results.

      • SCIESCOPUSKCI등재

        Design and Implementation of an Adaptive Sliding-Mode Observer for Sensorless Vector Controlled Induction Machine Drives

        Zhang, Yanqing,Yin, Zhonggang,Liu, Jing,Tong, Xiangqian The Korean Institute of Electrical Engineers 2018 Journal of Electrical Engineering & Technology Vol.13 No.3

        An adaptive sliding-mode observer for speed estimation in sensorless vector controlled induction machine drives is proposed in this paper to balance the dilemma between the requirement of fast reaching transient and the chattering phenomenon reduction on the sliding-mode surface. It is well known that the sliding-mode observer (SMO) suffers from the chattering phenomenon. However, the reduction of the chattering phenomenon will lead to a slow transient process. In order to balance this dilemma, an adaptive exponential reaching law is introduced into SMO by optimizing the reaching way to the sliding-mode surface. The adaptive exponential reaching law is based on the options of an exponential term that adapts to the variations of the sliding-mode surface and system states. Moreover, the proposed sliding-mode observer considering adaptive exponential reaching law, which is called adaptive sliding-mode observer (ASMO), is capable for reducing the chattering phenomenon and decreasing the reaching time simultaneously. The stability analysis for ASMO is achieved based on Lyapunov stability theory. Simulation and experimental results both demonstrate the correctness and the effectiveness of the proposed method.

      • KCI등재

        Linking UT Signals to Properties of Weakly Bonded Composites by Four-point Bending Test

        Ting Zhang,Xiangqian Li,Leishan Chen 한국섬유공학회 2022 Fibers and polymers Vol.23 No.3

        A new method of producing accurately controlled bond ratios in weakly bonded composites was developed toinvestigate the influence of adhesive porosity on mechanical properties of the bondline. The ultrasonic A-scan was used todetect weak bonds in adhesive joints and the ultrasonic A-scan signals of weak bonds were analyzed to link with adhesiveporosity. As well, relations of adhesive porosities to four-point bending (4PB) were established based on experimental andnumerical results. It was found that the amplitudes of amplitudes of A-scan signals of the adhesive interface areapproximately linear functions of the bond ratios, as well as the adhesive porosities. The shear strength of bondlinesdecreases linearly with the bond ratios. Based on above results, properties of weak bonds could be evaluated by the UT(Ultrasonic Test) signals, which is of great value in engineering application.

      • KCI등재

        A Novel Speed Estimation Method of Induction Motors Using Real-Time Adaptive Extended Kalman Filter

        Yanqing Zhang,Zhonggang Yin,Guoyin Li,Jing Liu,Xiangqian Tong 대한전기학회 2018 Journal of Electrical Engineering & Technology Vol.13 No.1

        To improve the performance of sensorless induction motor (IM) drives, a novel speed estimation method based on the real-time adaptive extended Kalman filter (RAEKF) is proposed in this paper. In this algorithm, the fuzzy factor is introduced to tune the measurement covariance matrix online by the degree of mismatch between the actual innovation and the theoretical. Simultaneously, the fuzzy factor can be continuously self-tuned tuned by the fuzzy logic reasoning system based on Takagi–Sugeno (T-S) model. Therefore, the proposed method improves the model adaptability to the actual systems and the environmental variations, and reduces the speed estimation error. Furthermore, a simple exponential function based on the fuzzy theory is used to reduce the computational burden, and the real-time performance of the system is improved. The correctness and the effectiveness of the proposed method are verified by the simulation and experimental results.

      • KCI등재

        Design and Implementation of an Adaptive Sliding-Mode Observer for Sensorless Vector Controlled Induction Machine Drives

        Yanqing Zhang,Zhonggang Yin,Jing Liu,Xiangqian Tong 대한전기학회 2018 Journal of Electrical Engineering & Technology Vol.13 No.3

        An adaptive sliding-mode observer for speed estimation in sensorless vector controlled induction machine drives is proposed in this paper to balance the dilemma between the requirement of fast reaching transient and the chattering phenomenon reduction on the sliding-mode surface. It is well known that the sliding-mode observer (SMO) suffers from the chattering phenomenon. However, the reduction of the chattering phenomenon will lead to a slow transient process. In order to balance this dilemma, an adaptive exponential reaching law is introduced into SMO by optimizing the reaching way to the sliding-mode surface. The adaptive exponential reaching law is based on the options of an exponential term that adapts to the variations of the sliding-mode surface and system states. Moreover, the proposed sliding-mode observer considering adaptive exponential reaching law, which is called adaptive sliding-mode observer (ASMO), is capable for reducing the chattering phenomenon and decreasing the reaching time simultaneously. The stability analysis for ASMO is achieved based on Lyapunov stability theory. Simulation and experimental results both demonstrate the correctness and the effectiveness of the proposed method.

      • KCI등재

        Expression and Regulation of Transcription Factor FoxA2 in Chronic Rhinosinusitis With and Without Nasal Polyps

        Qing Luo,Jia Zhang,Hongtian Wang,Fenghong Chen,Xi Luo,Beiping Miao,Xingmei Wu,Renqiang Ma,Xiangqian Luo,Geng Xu,Jianbo Shi,Huabin Li 대한천식알레르기학회 2015 Allergy, Asthma & Immunology Research Vol.7 No.5

        Purpose: Chronic rhinosinusitis (CRS) is characterized by the excessive production of mucus. However, the molecular mechanism underlying mucin overproduction in CRS with or without nasal polyps (CRSwNP and CRSsNP, respectively) is poorly understood. This study was conducted to assess the importance of the transcription factor FoxA2 in mucin production and to investigate the targeting of FoxA2 as a potential therapeutic strategy for mucus hypersecretion in CRS patients. Methods: We enrolled 15 CRSwNP patients, 15 CRSsNP patients, and 10 normal controls in this study. The expression levels of FoxA2, MUC5AC, and MUC5B in inflamed and healthy nasal tissues were examined via immunohistochemistry and quantitative reverse transcription-polymerase chain reaction, and the levels of several proinflammatory cytokines in nasal secretions were measured via FlowCytomix analysis. In addition, the expression of MUC5AC and FoxA2 was determined in polyp-derived epithelial cells and NCI-H292 cells after in vitro stimulation. Results: FoxA2 was significantly down-regulated, and MUC5AC and MUC5B were significantly up-regulated in both the CRSwNP and CRSsNP patients compared to the controls (P<0.05), and the protein level of FoxA2 was negatively associated with the IL-6 level in the CRS patients (P<0.05). IL-6 significantly increased MUC5AC expression but inhibited FoxA2 expression in vitro (P<0.05). Transfection with a FoxA2 expression plasmid significantly decreased MUC5AC promoter activity (P<0.05) and inhibited IL-6-induced MUC5AC production (P<0.05). In addition, clarithromycin significantly alleviated IL-6-induced FoxA2 suppression and decreased MUC5AC expression in vitro (P<0.05). Conclusions: Our findings suggest that FoxA2 may be considered a therapeutic target for the modulation of mucus hypersecretion in CRS patients.

      • Research on the Effect of Health food on Consumer Purchase Intention

        Ying-Mei Lee,Zhang Xiangqian,Wen-Tsann Lin,Meng-Hua Li,Hung-Lung Chang 대한산업공학회 2015 대한산업공학회 추계학술대회논문집 Vol.2015 No.11

        This study used the structural equation modeling (SEM) of SPSS and AMOS to verify the hypotheses on the correlation between various dimensions, which were all supported. The correlations were significantly positive. The results showed that the effect of consumer health concept on algae product knowledge is significantly positive, where path coefficient is 0.9, indicating that consumers with health concept are more willing to accept new algae product knowledge, thereby affecting their purchase intention on algae product.

      • KCI등재

        Influence of Filter Inductances and Number of Paralleled Grid-Connected Converters on the System’s Stable Region Under Weak Grid Condition

        Yang Shude,Sun Yipeng,Jiang Wei,Zhang Jiyong,Wang Qianlong,Tong Xiangqian 대한전기학회 2021 Journal of Electrical Engineering & Technology Vol.16 No.2

        It has been found that both the number of paralleled grid-connected converters and the fi lter inductance value will aff ect the system’s stability in weak grid condition. However, a quantitative study on this eff ect is missing in the current literature. The main contribution of this paper is to quantitatively evaluates the infl uence of the number of paralleled grid-connected converters as well as the inductance value of the L fi lters on the system’s stable region. It is fi rst revealed that, when the same controller design principles are applied for L -type grid-connected converters, the stable region of the paralleled grid-connected converter system is dependent on the ratio between the fi lter inductances and the number of paralleled converters. Specifi - cally, the stable region is proportional to the ratio. Compared to the qualitative analysis in previous work, this fi nding can provide quantitative guidelines on the fi lter inductors or control system design for grid-connected converter applications in weak grid. Finally, experimental tests are carried out using two paralleled grid-connected converters to confi rm the fi ndings.

      • KCI등재

        Ultra-Precision Diamond Turning Error Compensation via Iterative Learning from On-machine Measured Data

        ZaoZao Chen,WeiWei Huang,ZhiWei Zhu,XinQuan Zhang,LiMin Zhu,XiangQian Jiang 한국정밀공학회 2023 International Journal of Precision Engineering and Vol.24 No.12

        In ultra-precision diamond turning, the reduction of machining form errors can generally be achieved through on-machine measurement and compensation. However, the efficiency of conventional compensation methods is often insufficient, particularly when high form accuracy is required or when intricate surface topography and microstructures need to be machined. Consequently, this research proposes a novel machining error compensation method based on iterative learning from on-machine measured data to enhance the machining accuracy and compensation efficiency. The on-machine measurement system and cutting path generation algorithm are introduced first. Then, the compensation method via iterative learning is presented theoretically, demonstrating a higher convergence order compared to the conventional method. Finally, machining experiments involving the cutting of cosine surfaces are conducted, followed by measurements of the processed workpieces. The experimental results indicate that after four rounds of compensation using the conventional method, the peak-to-valley (PV) value of the form error is reduced to 0.1134 μm. In contrast, employing the proposed method, a similar value of 0.1156 μmis achieved after only two rounds of compensation. This highlights the significant reduction in compensation time facilitated by the proposed method. Furthermore, the measurement results verify that the proposed compensation method maintains excellent surface quality.

      • KCI등재

        Application of Near-Infrared Fluorescence Imaging with Indocyanine Green in Totally Laparoscopic Distal Gastrectomy

        Maoxing Liu,Jiadi Xing,Kai Xu,Peng Yuan,Ming Cui,Chenghai Zhang,Hong Yang,Zhendan Yao,Nan Zhang,Fei Tan,Xiangqian Su 대한위암학회 2020 Journal of gastric cancer Vol.20 No.3

        aPurpose: Recently, totally laparoscopic gastrectomy has been gradually accepted by surgeons worldwide for gastric cancer treatment. Complete dissection of the lymph nodes and the establishment of the surgical margin are the most important considerations for curative gastric cancer surgery. Previous studies have demonstrated that indocyanine green (ICG)-traced laparoscopic gastrectomy significantly improves the completeness of lymph node dissection. However, it remains difficult to identify the tumor location intraoperatively for gastric cancers that are staged ≤T3. Here, we investigated the feasibility of ICG fluorescence for lymph node mapping and tumor localization during totally laparoscopic distal gastrectomy. Materials and Methods: Preoperative and perioperative data from consecutive patients with gastric cancer who underwent a totally laparoscopic distal gastrectomy were collected and analyzed. The patients were categorized into the ICG (n=61) or the non-ICG (n=75) group based on whether preoperative endoscopic mucosal ICG injection was performed. Results: The ICG group had a shorter operation time and less intraoperative blood loss. Moreover, significantly more lymph nodes were harvested in the ICG group than the non-ICG group. No pathologically positive margin was found and there was no significant difference in either the proximal or distal surgical margins between the 2 groups. Conclusions: Near-infrared fluorescence imaging with ICG can be successfully used in totally laparoscopic distal gastrectomy, and it contributes to both the completeness of D2 lymph node dissection and confirmation of the gastric transection line. Well-designed prospective randomized studies are needed in the future to fully validate our findings.

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