Study of Montage Editing in Art Video

Yifei Wu,Hyung-gi Kim 중앙대학교 영상콘텐츠융합연구소 2018 TechArt :Journal of Arts and Imaging Science Vol.5 No.2

The Predictive Value of Magnetic Resonance Imaging-based Texture Analysis in Evaluating Histopathological Grades of Breast Phyllodes Tumor

Yifei Mao,Zhongtang Xiong,Songxin Wu,Zhiqing Huang,Ruoxian Zhang,Yuqin He,Yuling Peng,Yang Ye,Tianfa Dong,Hui Mai 한국유방암학회 2022 Journal of breast cancer Vol.25 No.2

Purpose: Knowing the distinction between benign and borderline/malignant phyllodes tumors (PTs) can help in the surgical treatment course. Herein, we investigated the value of magnetic resonance imaging-based texture analysis (MRI-TA) in differentiating between benign and borderline/malignant PTs. Methods: Forty-three women with 44 histologically proven PTs underwent breast MRI before surgery and were classified into benign (n = 26) and borderline/malignant groups (n = 18 [15 borderline, 3 malignant]). Clinical and routine MRI parameters (CRMP) and MRI-TA were used to distinguish benign from borderline/malignant PT. In total, 298 texture parameters were extracted from fat-suppression (FS) T2-weighted, FS unenhanced T1-weighted, and FS first-enhanced T1-weighted sequences. To evaluate the diagnostic performance, receiver operating characteristic curve analysis was performed for the K-nearest neighbor classifier trained with significantly different parameters of CRMP, MRI sequence-based TA, and the combination strategy. Results: Compared with benign PTs, borderline/malignant ones presented a higher local recurrence (p = 0.045); larger size (p < 0.001); different time-intensity curve pattern (p = 0.010); and higher frequency of strong lobulation (p = 0.024), septation enhancement (p = 0.048), cystic component (p = 0.023), and irregular cystic wall (p = 0.045). TA of FS T2- weighted images (0.86) showed a significantly higher area under the curve (AUC) than that of FS unenhanced T1-weighted (0.65, p = 0.010) or first-enhanced phase (0.72, p = 0.049) images. The texture parameters of FS T2-weighted sequences tended to have a higher AUC than CRMP (0.79, p = 0.404). Additionally, the combination strategy exhibited a similar AUC (0.89, p = 0.622) in comparison with the texture parameters of FS T2-weighted sequences. Conclusion: MRI-TA demonstrated good predictive performance for breast PT pathological grading and could provide surgical planning guidance. Clinical data and routine MRI features were also valuable for grading PTs.

Multimodal Perturbation and Cluster Pruning Based Selective Ensemble Classifier and Its Iron Industrial Application

Qiannan Wu,Yifei Sun,Xuefeng Yan,Lihua Lv 제어·로봇·시스템학회 2023 International Journal of Control, Automation, and Vol.21 No.11

The selective ensemble aims to search the optimal subset balanced accuracy and diversity from the original base classifier set to construct an ensemble classifier with strong generalization performance. A selective ensemble classifier named BRFS-APCSC is proposed in this paper, which realizes the generation and selection of a set of accurate and diverse base classifiers respectively. In the first step, a multimodal perturbation method is introduced to train distinct base classifiers. The method perturbs the sample space by Bootstrap and disturbs the feature space under a newly proposed semi-random feature selection, which is a combination of the core attribute theory and the improved maximum relevance minimum redundancy algorithm. Then, to search the optimal classifier subset, affinity propagation clustering is added to cluster base classifiers in the first step, then the base classifiers are regarded as features so that the improved maximum relevance minimum redundancy algorithm is applied to select parts of base classifiers from each cluster for integration. UCI datasets and an actual dataset of semi-decarbonization are employed to verify the performance of BRFS-APCSC. The experimental results demonstrate that BRFS-APCSC has significantly difference with other selective ensemble methods and improve the classification accuracy.

Investigation on bubble snap-off in 3-D pore-throat micro-structures

Yining Wu,Sisi Fang,Caili Dai,Yongpeng Sun,Jichao Fang,Yifei Liu,Long He 한국공업화학회 2017 Journal of Industrial and Engineering Chemistry Vol.54 No.-

Bubble behaviors in the single and cascaded three-dimensional (3-D) pore-throat micromodels were studied at the operating ranging from 0.0007 to 0.0249. It was found that the average size of daughter bubbles decreased with the rising of the pore-throat ratio, length of throat and mother bubble velocity. The variation of the average size of daughter bubbles with capillary number could be scaled with a power law. In addition, the bubble breakup mainly occurred in the first pore-throat structure and the size of the daughter bubbles maintained almost stable.

Indirect Adaptive Robust Control Design for Course Tracking of Ships Subject to Unknown Control Coefficient and Disturbances

Jinbo Wu,Chenghao Zeng,Yifei Hu 제어·로봇·시스템학회 2021 International Journal of Control, Automation, and Vol.19 No.6

For course control of ships with unknown control coefficient and model parameters, an indirect adaptive robust controller, in which the parameter estimation law and the control law are designed separately, is proposed. This design method can achieve not only excellent course control performance but also accurate parameter estimates for secondary purposes such as assisting in ship maneuvering decision. Firstly, a Nussbaum function is combined with the adaptive dynamic surface control method to design a strong robust controller which can ensure the stabilityof the closed-loop ship course control system in spite of parameter uncertainties, unknown control coefficient and disturbances. Secondly, the nonlinear model for ship steering is converted into linear form by using the X-swapping technique. And a modified least-squares identification algorithm is then proposed to estimate the unknown model parameters. The global uniform ultimate boundedness of all signals of the resulting closed-loop system is guaranteed via Lyapunov stability theory. Lastly, simulation results are executed to demonstrate the effectiveness of theproposed design method.

Characteristic Model-based Adaptive Control with Genetic Algorithm Estimators for Four-PMSM Synchronization System

Yang Gao,Yifei Wu,Xiang Wang,Qingwei Chen 제어·로봇·시스템학회 2020 International Journal of Control, Automation, and Vol.18 No.6

For four-PMSM synchronization systems, the complex structure, nonlinearities and uncertainties make accurate modeling and precise control difficult to realize. This article proposes an easily realized adaptive control scheme for four-PMSM synchronization system. This control scheme combines novel characteristic modeling, genetic algorithm and terminal sliding mode control together. Firstly, the four-PMSM synchronization system is described by characteristic model, which significantly simplifies system’s dynamic model without losing its highorder characteristics. Secondly, a genetic algorithm estimator is newly designed to estimate the real-time value of parameters in characteristic model, which is the key issue in obtaining an accurate system model. Thirdly, an adaptive discrete-time terminal sliding mode controller is proposed based on the characteristic model to enhance system robustness. Also, this controller can eliminate chattering effect when system is reversing. Then, the stability of the closed-loop system is proved by Lyapunov stability theorem. Finally, simulation and experiment results verify the adaptiveness and robustness of the proposed control scheme.

Investigation of a Novel IGCT Module for DC Circuit Breaker

Qiang Yi,Yifei Wu,Yi Wu,Fei Yang,Zhihui Zhang,Chong Gao 전력전자학회 2019 ICPE(ISPE)논문집 Vol.2019 No.5

Power semiconductors for DC circuit breaker (DCCB) have attracted great attentions due to their fast and arc-less operation under full-range current-breaking. Since the robustness of Integrated Gate-Commutated Thyristor (IGCT) is the highest among all full-control power semiconductors, it becomes the perfect power semiconductor candidate for DC circuit breaker. In this paper, the principle and operation of hybrid circuit breaker are introduced. Technical analysis of full-control power semiconductor is conducted and IGCT is the best choice for HCB. Then, A novel power semiconductor circuit based on two IGCTs, diode-bridge, snubber-circuit and MOV is proposed and designed both topologically and structurally. The selection of full-control power semiconductor is discussed and fast recover diode must be used to ensure reliability. Furthermore, the internal current distribution is analyzed. Finally, a test of a single-stage IGCT module prototype demonstrates successful current-breaking at over 10kA and below 4kV, which is promising in the area of fault protection in future MVDC distribution system.

Antibacterial activity of florfenicol composite nanogels against Staphylococcus aureus small colony variants

Liu, Jinhuan,Ju, Mujie,Wu, Yifei,Leng, Nannan,Algharib, Samah Attia,Luo, Wanhe The Korean Society of Veterinary Science 2022 Journal of Veterinary Science Vol.23 No.5

Background: Florfenicol might be ineffective for treating Staphylococcus aureus small colony variants (SCVs) mastitis. Objectives: In this study, florfenicol-loaded chitosan (CS)-sodium tripolyphosphate (TPP) composite nanogels were prepared to allow targeted delivery to SCV infected sites. Methods: The formulation screening, the characteristics, in vitro release, antibacterial activity, therapeutic efficacy, and biosafety of the florfenicol composite nanogels were studied. Results: The optimized formulation was obtained when the CS and TPP were 10 and 5 mg/mL, respectively. The encapsulation efficiency, loading capacity, size, polydispersity index, and zeta potential of the optimized florfenicol composite nanogels were 87.3% ± 2.7%, 5.8% ± 1.4%, 280.3 ± 1.5 nm, 0.15 ± 0.03, and 36.3 ± 1.4 mv, respectively. Optical and scanning electron microscopy showed that spherical particles with a relatively uniform distribution and drugs might be incorporated in cross-linked polymeric networks. The in vitro release study showed that the florfenicol composite nanogels exhibited a biphasic pattern with the sustained release of 72.2% ± 1.8% at 48 h in pH 5.5 phosphate-buffered saline. The minimal inhibitory concentrations of commercial florfenicol solution and florfenicol composite nanogels against SCVs were 1 and 0.25 ㎍/mL, respectively. The time-killing curves and live-dead bacterial staining showed that the florfenicol composite nanogels were concentration-dependent. Furthermore, the florfenicol composite nanogels displayed good therapeutic efficacy against SCVs mastitis. Biological safety studies showed that the florfenicol composite nanogels might be a biocompatible preparation because of their non-toxic effects on the renal tissue and liver. Conclusions: Florfenicol composite nanogels might improve the treatment of SCV infections.

Participation of CCL1 in Snail-Positive Fibroblasts in Colorectal Cancer Contribute to 5-Fluorouracil/Paclitaxel Chemoresistance

Ziqian Li,Kaying Chan,Yifei Qi,Linlin Lu,Fen Ning,Mengling Wu,Haifang Wang,Yuan Wang,Shaohui Cai,Jun Du 대한암학회 2018 Cancer Research and Treatment Vol.50 No.3

Purpose Cancer-associated fibroblasts (CAFs) activated by cancer cells has a central role in development and malignant biological behavior in colorectal cancer (CRC). Adult fibroblasts do not express Snail, but Snail-positive fibroblasts are discovered in the stroma of malignant CRC and reported to be the key role to chemoresistance. However, the reciprocal effect of CAFs expressed Snail to chemoresistance on CRC cells and the underlying molecular mechanisms are not fully characterized. Materials and Methods Snail-overexpressed 3T3 stable cell lines were generated by lipidosome and CT26 mixed with 3T3-Snail subcutaneous transplanted CRC models were established by subcutaneous injection. Cell Counting Kit-8, flow cytometry and western blotting assays were performed, and immunohistochemistry staining was studied. The cytokines participated in chemoresistance was validated with reverse transcriptase-polymerase chain reaction and heatmap. Results Snail-expression fibroblasts are discovered in human and mouse spontaneous CRCs. Overexpression of Snail induces 3T3 fibroblasts transdifferentiation to CAFs. CT26 co-cultured with 3T3-Snail resisted the impairment from 5-fluorouracil and paclitaxel in vitro. The subcutaneous transplanted tumor models included 3T3-Snail cells develop without restrictions even after treating with 5-fluorouracil or paclitaxel. Moreover, these chemoresistant processes may be mediated by CCL1 secreted by Snail-expression fibroblasts via transforming growth factor /nuclear factor-B signaling pathways. Conclusion Taken together, Snail-expressing 3T3 fibroblasts display CAFs properties that support 5-fluorouracil and paclitaxel chemoresistance in CRC via participation of CCL1 and suggest that inhibition of the Snail-expression fibroblasts in tumor may be a useful strategy to limit chemoresistance.

Antibacterial activity of a novel florfenicol-loaded chitosan-sodium tripolyphosphate composite nanogels in vitro and in mice against Staphylococcus aureus small colony variants

Jinhuan Liu,Mujie Ju,Yifei Wu,Nannan Leng,Samah Attia Algharib,Wanhe Luo 대한수의학회 2022 Journal of Veterinary Science Vol.23 No.5

Background: Florfenicol might be ineffective for treating Staphylococcus aureus small colony variants (SCVs) mastitis. Objectives: In this study, florfenicol-loaded chitosan (CS)-sodium tripolyphosphate (TPP) composite nanogels were prepared to allow targeted delivery to SCV infected sites. Methods: The formulation screening, the characteristics, in vitro release, antibacterial activity, therapeutic efficacy, and biosafety of the florfenicol composite nanogels were studied. Results: The optimized formulation was obtained when the CS and TPP were 10 and 5 mg/mL, respectively. The encapsulation efficiency, loading capacity, size, polydispersity index, and zeta potential of the optimized florfenicol composite nanogels were 87.3% ± 2.7%, 5.8% ± 1.4%, 280.3 ± 1.5 nm, 0.15 ± 0.03, and 36.3 ± 1.4 mv, respectively. Optical and scanning electron microscopy showed that spherical particles with a relatively uniform distribution and drugs might be incorporated in cross-linked polymeric networks. The in vitro release study showed that the florfenicol composite nanogels exhibited a biphasic pattern with the sustained release of 72.2% ± 1.8% at 48 h in pH 5.5 phosphate-buffered saline. The minimal inhibitory concentrations of commercial florfenicol solution and florfenicol composite nanogels against SCVs were 1 and 0.25 μg/mL, respectively. The time-killing curves and live–dead bacterial staining showed that the florfenicol composite nanogels were concentration-dependent. Furthermore, the florfenicol composite nanogels displayed good therapeutic efficacy against SCVs mastitis. Biological safety studies showed that the florfenicol composite nanogels might be a biocompatible preparation because of their non-toxic effects on the renal tissue and liver. Conclusions: Florfenicol composite nanogels might improve the treatment of SCV infections.