Comparison of Magnetic Force Calculation on Permanent Magnets with Models of Equivalent Magnetic Charge and Magnetizing Current

Yuyang Zhang,Yonggang Leng,Jinjun Liu,Dan Tan 한국자기학회 2019 Journal of Magnetics Vol.24 No.3

Accurate magnetic force calculation is essential to effectively analyzing a system or device containing magnets. Among several approaches used in the interacting magnetic force calculation of permanent magnets, equivalent magnetic charge and equivalent magnetizing current models are widely adopted. In this paper, we choose cubes and cylinders as calculating objects to investigate the detailed calculation procedures. Higher calculation accuracy of the equivalent magnetizing current model is verified by comparison between simulation and experiment results. Furthermore, we analyze the relations between two models and discriminate their equivalence in the magnetic force calculation respectively at both micro and macro scale. Reference basis for choosing a proper model to calculate magnetic force is provided in this work, which is beneficial for the design of electro-mechanical structures with permanent magnets.

Study on Magnetic Force Calculation of Spherical Permanent Magnets

Yuyang Zhang,Yonggang Leng,Dan Tan,Jinjun Liu Korean Magnetics Society 2018 Journal of Magnetics Vol.23 No.4

This paper presents three approaches to calculate the interacting magnetic force about spherical permanent magnet, respectively based on magnetic dipole-dipole model, equivalent magnetic charge model and equivalent magnetizing current model. We use all of three models to fully calculate and study the behaviors of lateral and axial forces with respect to the related positions between a pair of spherical magnets. The accuracies of the calculation results are compared with the experimental data. In conclusion, the magnetic dipole-dipole model has the most advantageous accuracy and efficiency for the magnetic force calculation about spherical permanent magnets on account of the particularity of sphere. Our study provides an important criterion for choosing a proper method to calculate magnetic force about spherical permanent magnet.

FDG-PET Identification of Infected Pulmonary Artery Conduit Following Tetralogy of Fallot (TOF) Repair

Yuyang Zhang,Hadyn Williams,Darko Pucar 대한핵의학회 2017 핵의학 분자영상 Vol.51 No.1

Tetralogy of Fallot (TOF) is one of the most common forms of cyanotic congenital heart disease usually managed by serial surgical repairs. The repaired prosthetic valve or conduit is susceptible to life-threatening infection. FDG-PET is an effective alternative to evaluate the source of infection when other examinations are inconclusive. We report an unusual case of an infected pulmonary artery conduit after TOF repair although the echocardiogram was negative for vegetation, which was later confirmed by surgery and pathology. The case highlights the role of FDG-PETas a problem-solving tool for potential endocarditis and cardiac device infection cases after complex cardiac surgery.

Unusual Contiguous Soft Tissue Spread of Advanced Malignant Mesothelioma Detected by FDG PET/CT

Yuyang Zhang,Jamie Edwards,Hadyn Williams,Zhonglin Hao,Samir Khleif,Darko Pucar 대한핵의학회 2017 핵의학 분자영상 Vol.51 No.2

Malignant pleural mesothelioma (MPM) is atumor of mesodermal origin that arises from the serosaof the pleura, peritoneum, pericardium or tunicavaginalis. MPM is well known to have a poor prognosiswith a median survival time of 12 months. Accurate diagnosis,staging and restaging of MPM are crucial with[18F] flurodeoxy-D-glucose positron emission tomography(FDG PET/CT) playing an increasingly importantrole. Here we report a case of MPM with unusual contiguoussoft tissue spread of the tumor along the dermaland fascial planes characterized by PET/CT. Given thatthe loco-regional tumor in the thorax was under controlon PET/CT, the death of the patient was most likelyassociated with physiologic or metabolic causes associatedwith an extra-thoracic tumor.

Cross-Domain Text Sentiment Classification Method Based on the CNN-BiLSTM-TE Model

( Yuyang Zeng ),( Ruirui Zhang ),( Liang Yang ),( Sujuan Song ) 한국정보처리학회 2021 Journal of information processing systems Vol.17 No.4

To address the problems of low precision rate, insufficient feature extraction, and poor contextual ability in existing text sentiment analysis methods, a mixed model account of a CNN-BiLSTM-TE (convolutional neural network, bidirectional long short-term memory, and topic extraction) model was proposed. First, Chinese text data was converted into vectors through the method of transfer learning by Word2Vec. Second, local features were extracted by the CNN model. Then, contextual information was extracted by the BiLSTM neural network and the emotional tendency was obtained using softmax. Finally, topics were extracted by the term frequency-inverse document frequency and K-means. Compared with the CNN, BiLSTM, and gate recurrent unit (GRU) models, the CNN-BiLSTM-TE model’s F1-score was higher than other models by 0.0147, 0.006, and 0.0052, respectively. Then compared with CNN-LSTM, LSTM-CNN, and BiLSTM-CNN models, the F1-score was higher by 0.0071, 0.0038, and 0.0049, respectively. Experimental results showed that the CNN-BiLSTM-TE model can effectively improve various indicators in application. Lastly, performed scalability verification through a takeaway dataset, which has great value in practical applications.

Construction of Abalone Sensory Texture Evaluation System Based on BP Neural Network

Xiaochen Li,Yuyang Zhao,Renjie Li,Ning Zhang,Xue-Heng Tao,이응주 한국멀티미디어학회 2019 멀티미디어학회논문지 Vol.22 No.7

The effects of different heat treatments on the sensory characteristics of abalones are studied in this study. In this paper, the sensory evaluation of abalone samples under different heat treatment conditions is carried out, and the evaluation results are analyzed. The three-dimensional (3D) scanning and reverse engineering are used in tooth modeling of the sensory evaluation of abalone samples under different heat treatment conditions. Besides, the chewing movement models are simplified into three modes, including the cutting mode, compressing mode and grinding mode, which are simulated using finite element simulation. The elastic modulus of the abalone samples is obtained through the compression testing using a texture analyzer to distinguish their material properties under different heat treatments and to obtain simulated mechanical parameters. Finally, taking the mechanical parameters of the finite element simulation of abalone chewing as input and sensory evaluation parameters as the output, BP neural network is established in which the sensory texture evaluation model of abalone samples is obtained. Through verification, the neural network prediction model can meet the requirements of food texture evaluation, with an average error of 9.12%.

Optimal Design of Micro-expanded ECC and Its Interfacial Bonding Property with Steel Tube

Shuling Gao,Yuyang Zhang 대한토목학회 2023 KSCE Journal of Civil Engineering Vol.27 No.10

The large shrinkage strain of Engineered Cementitious Composites (ECC) seriously affects its combined application with steel tube in engineering. In order to reduce the shrinkage of ECC and realize the effective bonding between ECC and steel tube, this paper studied the effects of single or multiple doped of expansive and internal curing agent on the shrinkage and mechanical properties of ECC, and tested the interfacial bond strength between ECC and steel tube. CaO and MgO compound expansive agent (CME), calcium sulfoaluminate expansive agent (HCSA), super water-absorbing polymer (SAP) internal curing agent are chosen for test. The results show that ECC mixed with 10% CME expansive agent and 0.2% SAP shows a slight expansion under the condition of sprinkling water curing. Moreover, the push-out test shows that the bond strength between micro-expanded ECC and steel tube reaches 1.27 MPa, which is nearly 2 times higher than that of the ordinary ECC, and higher than the bond strength of C50 filled steel tube. This paper provides the test and theoretical basis for the joint application of ECC with steel tube.

Fluorinated and Charged Non-woven Polypropylene Electret Fiber Membrane: A Novel Way in Transformer Oil Regeneration

Nianrong Zhou,Xiao He,Yuyang Yan,Xinliang Guo,Linshan Zhang,Yunhua He,Xiangyu Tan,Zhengyun Fang 한국전기전자재료학회 2022 Transactions on Electrical and Electronic Material Vol.23 No.2

The regeneration of transformer oil is a trending topic in the dielectric research field. However, the normal way of regeneration requires high cost and complicate process. In this paper, the non-woven polypropylene (PP) electret films were modifi ed by fluorination and corona method to achieve the regeneration function for transformer oil. The results show that the C-H bonds in polypropylene were replaced by C-F bonds during the fluorination process, resulting in the mean diameter of the fibers being decreased to a value of 1.7 μm. The increased roughness of the fi bers leads to super hydrophobicity. Further research revealed that the insulation properties of aging oil recovered after fi ltration by corona charged fl uorinated fi ber membranes. The result is especially signifi cant for breakdown voltage, the values of which reached half of the original insulating oil. In conclusion, the combination of fl uorinating and corona charging method on PP fi ber membrane shows great potential for insulation oil regeneration.

Impact of Chronic Lateral Ankle Instability with Lateral Collateral Ligament Injuries on Biochemical Alterations in the Cartilage of the Subtalar and Midtarsal Joints Based on MRI T2 Mapping

Tao Hongyue,Hu Yiwen,Lu Rong,Zhang Yuyang,Xie Yuxue,Chen Tianwu,Chen Shuang 대한영상의학회 2021 Korean Journal of Radiology Vol.22 No.3

Objective: To quantitatively assess biochemical alterations in the cartilage of the subtalar and midtarsal joints in chronic lateral ankle instability (CLAI) patients with isolated anterior talofibular ligament (ATFL) injuries and combined calcaneofibular ligament (CFL) injuries using MRI T2 mapping. Materials and Methods: This study was performed according to regulations of the Committee for Human Research at our institution, and written informed consent was obtained from all participants. Forty CLAI patients (26 with isolated ATFL injuries and 14 with combined ATFL and CFL injuries) and 25 healthy subjects were recruited for this study. All participants underwent MRI scans with T2 mapping. Patients were assessed with the American Orthopedic Foot and Ankle Society (AOFAS) rating system. The subtalar and midtarsal joints were segmented into 14 cartilage subregions. The T2 value of each subregion was measured from T2 mapping images. Data were analyzed with ANOVA, the Student’s t test, and Pearson’s correlation coefficient. Results: T2 values of most subregions of the subtalar joint and the calcaneal facet of the calcaneocuboid joint in CLAI patients with combined CFL injuries were higher than those in healthy controls (all p < 0.05). However, there were no significant differences in T2 values in subtalar and midtarsal joints between patients with isolated ATFL injuries and healthy controls (all p > 0.05). Moreover, T2 values of the medial talar subregions of the posterior subtalar joint in patients with combined CFL injuries showed negative correlations with the AOFAS scores (r = -0.687, p = 0.007; r = -0.609, p = 0.021, respectively). Conclusion: CLAI with combined CFL injuries can lead to cartilage degeneration in subtalar and calcaneocuboid joints, while an isolated ATFL injury might not have a significant impact on the cartilage in these joints.

A novel ethylene-responsive factor IbERF4 from sweetpotato negatively regulates abiotic stress

Yu Yang,김호수,Ma Peiyong,Jia Zhaodong,Guo Xiaoding,Xie Yizhi,곽상수,Zhang Peng,Bian Xiaofeng 한국식물생명공학회 2020 Plant biotechnology reports Vol.14 No.4

The ERF (ethylene-responsive element-binding factor) transcription factor family plays important roles in abiotic and biotic stress responses in plants. An EAR motif-containing ERF gene, IbERF4, was isolated from sweetpotato [Ipomoea batatas (L.) Lam]. IbERF4 was highly expressed in the early stage of storage roots and can be induced by various stresses. By overexpressing IbERF4 in Arabidopsis, the transgenic Arabidopsis showed greater sensitivity to drought and salt stress by down-regulating stress-related genes, such as rd22, rd29, AtCBF1 and AtCBF2. Overexpressing IbERF4 in sweetpotato made the transgenic sweetpotato more sensitive to salt stress and made propagating new seedlings more difficult. Consistently, the transcriptomic profiling results showed that genes involved in oxidative stress were significantly down-regulated in sweetpotato overexpression lines. These results indicated that IbERF4 plays as key regulators in sweetpotato abiotic stress.