The Nonlinear Equivalent Input Disturbance Coordinated Control for Enhancing the Stability of Hydraulic Generator System

Lan‑Mei Cong,Xiao‑Cong Li 대한전기학회 2020 Journal of Electrical Engineering & Technology Vol.15 No.2

Hydraulic generator plays more important roles as a renewable clean energy in improving stability. As hydraulic generator enjoys strong nonlinear properties, traditional linearized control method may holds worse adaptability for vary disturbances. In order to solve the problem, a Nonlinear Equivalent Input Disturbance Coordinated Control (NEIDCC) method is proposed in this paper. The objective functions related to system control performance are frstly determined. Then the multi-objective equations satisfying the Brunovsky normal form are derived, by which the nonlinear control problem is transformed to linear space to be solved. The nonlinear equivalent control law is obtained from the linear law by calculating the Γ derivative of the objective functions. When the system is subjected to diferent disturbances, the designed NEIDCC control law supports dynamic damping by observing the disturbance to stabilize the oscillations. As a result, the control system holds good performance. The simulation results of the designed hydraulic turbine generator control system demonstrate the efectiveness of the NEIDCC method.

RESULTS ON MEROMORPHIC FUNCTIONS SHARING THREE VALUES WITH THEIR DIFFERENCE OPERATORS

Xiao-Min Li,Hong-Xun Yi,Cong-Yun Kang 대한수학회 2015 대한수학회보 Vol.52 No.5

Under the restriction of finite order, we prove two uniqueness theorems of nonconstant meromorphic functions sharing three values with their difference operators, which are counterparts of Theorem 2.1 in [6] for a finite-order meromorphic function and its shift operator.

The Relationship Between Preoperative Cervical Sagittal Balance and Clinical Outcome of Patients With Hirayama Disease Treated With Anterior Cervical Discectomy and Fusion

Xiao Lu,Guang-Yu Xu,Cong Nie,Yu Xuan Zhang,Jian Song,Jianyuan Jiang 대한척추신경외과학회 2021 Neurospine Vol.18 No.3

Objective: Anterior cervical discectomy and fusion (ACDF) is a common surgical method used to treat patients with Hirayama disease. And sagittal balance indexes have been revealed to be predictors of clinical outcomes in patients with cervical diseases, but their relationships with ACDF-treated Hirayama disease outcomes remain unknown. The purpose of this study is to evaluate the relationship of preoperative cervical sagittal balance indexes and clinical outcomes in ACDF-treated Hirayama disease patients. Methods: Eighty patients with Hirayama disease treated by ACDF were reviewed retrospectively. Six cervical sagittal balance parameters were collected including Cobb angle, T1 slope, C1–7 sagittal vertical axis (SVA), C2–7 SVA, center of gravity of the head (CGH)-C7 SVA, range of motion. The recovery outcomes of the patients were divided into 2 groups by Odom score and the differences in recovery between the 2 groups were confirmed by electromyography. The correlation between imaging parameters and postoperative outcome was evaluated with logistic regression. The receiver operating characteristic (ROC) curve and area under the ROC curve (AUC) were used to evaluate the significant result of logistic regression and the optimal diagnostic value. Results: Only 2 parameters, Cobb angle and CGH-C7 SVA, showed statistical correlation with the postoperative outcome assessment by logistic regression. AUC of Cobb angle and CGH-C7 SVA were 0.559 and 0.702 respectively. The optimal predictive threshold was 1.50° and 5.40 mm, respectively. Conclusion: A larger Cobb angle and smaller CGH-C7 SVA seemed to correlate with a better postoperative outcome. These 2 factors could be used to predict the outcome of surgical treatment of Hirayama disease preoperatively.

Metabolic Module Mining Based on Independent Component Analysis in Arabidopsis thaliana

Xiao Han,김재연,Cong Chen,현태경,Ritesh Kumar 한국분자세포생물학회 2012 Molecules and cells Vol.34 No.3

Independent Component Analysis (ICA) has been intro-duced as one of the useful tools for gene-functional dis-covery in animals. However, this approach has been poorly utilized in the plant sciences. In the present study, we have exploited ICA combined with pathway enrichment analysis to address the statistical challenges associated with genome-wide analysis in plant system. To generate an Arabidopsis metabolic platform, we collected 4,373 Affy- metrix ATH1 microarray datasets. Out of the 3,232 metabolic genes and transcription factors, 99.47% of these genes were identified in at least one component, indicating the coverage of most of the metabolic pathways by the components. During the metabolic pathway enrichment analysis, we found components that indicate an independent regulation between the isoprenoid biosynthesis pathways. We also utilized this analysis tool to investigate some transcription factors involved in secondary cell wall bio-genesis. This approach has identified remarkably more transcription factors compared to previously reported analysis tools. A website providing user-friendly searching and downloading of the entire dataset analyzed by ICA is available at http://kimjy.gnu.ac.kr/ICA.files/slide0002.htm. ICA combined with pathway enrichment analysis might provide a powerful approach for the extraction of the components responsible for a biological process of interest in plant systems.

Model Tests of Jacked-Pile Penetration into Sand Using Transparent Soil and Incremental Particle Image Velocimetry

Cong Liu,Xiao-Wei Tang,Huanwei Wei,Pengpeng Wang,Honghua Zhao 대한토목학회 2020 KSCE JOURNAL OF CIVIL ENGINEERING Vol.24 No.4

This paper presents a series of physical modelling tests of jacked-pile penetration into sand, combining the transparent soil and incremental reliability-guided particle image velocimetry, which provides a non-intrusively internal deformation measurement approach to monitor the internal movement of soil caused by jacked-pile penetration. The difference between the full-model test and the half-model test was analyzed quantitatively for the first time. This paper aims to provide some new insight into the penetration mechanisms of different shapes of pile tip. In addition, the phenomenon of meta-stable sand plug in the process of jacked-pile penetration was studied by means of the method of partial replacement with dyed particles. Experimental evidence has shown that the boundary and interaction effect causes the experimental phenomenon of the half-model test to be different from the true condition. The shape effect of pile tip on the governing penetration mechanisms was discussed, and the disturbance effect of different shapes of pile tip was evaluated and compared based on a large number of model tests and published literatures. The paper intuitively demonstrates that the different penetration mechanism of flat-ended pile and cone-ended pile is mainly due to the formation of the meta-stable sand plug beneath the pile tip.

Carbon-silica composites supported Pt as catalyst for asymmetric hydrogenation of ethyl 2-oxo-4-phenylbutyrate

Cong Mao,Jie Zhang,Meitian Xiao,Yongjun Liu,Xueqin Zhang 한국물리학회 2018 Current Applied Physics Vol.18 No.12

Mesoporous carbon-silica composites supported Pt nanoparticle catalysts (Pt/MCS) were firstly applied to the heterogeneous asymmetric hydrogenation of ethyl 2-oxo-4-phenylbutyrate (EOPB). A series of different silica contents were investigated in the fabrication of this mesoporous material. When the volume of added tetraethyl orthosilicate (TEOS) during the preparation of composites is 8 mL, Pt/MCS-8 holds carbon and silica as the main components and possesses relatively strong acidity, mesoporous structures with micropores, appropriate Pt nanoparticle size and high dispersibility showing by XRD, XPS, TPD, N2 sorption and TEM. These properties cause its good catalytic performance in the heterogeneous asymmetric hydrogenation of EOPB with the enantiomeric excess value and conversion up to 85.6% and 97.8%, respectively.

Bagging deep convolutional autoencoders trained with a mixture of real data and GAN-generated data

( Cong Hu ),( Xiao-jun Wu ),( Zhen-qiu Shu ) 한국인터넷정보학회 2019 KSII Transactions on Internet and Information Syst Vol.13 No.11

While deep neural networks have achieved remarkable performance in representation learning, a huge amount of labeled training data are usually required by supervised deep models such as convolutional neural networks. In this paper, we propose a new representation learning method, namely generative adversarial networks (GAN) based bagging deep convolutional autoencoders (GAN-BDCAE), which can map data to diverse hierarchical representations in an unsupervised fashion. To boost the size of training data, to train deep model and to aggregate diverse learning machines are the three principal avenues towards increasing the capabilities of representation learning of neural networks. We focus on combining those three techniques. To this aim, we adopt GAN for realistic unlabeled sample generation and bagging deep convolutional autoencoders (BDCAE) for robust feature learning. The proposed method improves the discriminative ability of learned feature embedding for solving subsequent pattern recognition problems. We evaluate our approach on three standard benchmarks and demonstrate the superiority of the proposed method compared to traditional unsupervised learning methods.

The Lymphatic Drainage Pattern of Internal Mammary Sentinel Lymph Node Identified by Small Particle Radiotracer (99mTc-Dextran 40) in Breast

Xiao-Shan Cao,Guo-Ren Yang,Bin-Bin Cong,Peng-Fei Qiu,Yong-Sheng Wang 대한암학회 2019 Cancer Research and Treatment Vol.51 No.2

Purpose The purpose of this study was to detect the lymphatic drainage pattern of internal mammary area and verify the concept of internal mammary sentinel lymph node (IM-SLN) in breast. Materials and Methods A small particle radiotracer (99mTc-Dextran 40) was prepared and tested. 99mTc-Dextran 40 was injected into intraparenchyma at the sound breast by a modified radiotracer injection technique. Subsequently, dynamic single-photon emission computed tomography (SPECT), computed tomography (CT), and SPECT/CT combination images were performed to identify the radioactive lymph vessels and internal mammary lymph nodes (IMLNs). The direction of lymph drainage and the location of the IMLNs were identified in the SPECT/CT imaging. Results The radiochemical purity of 99mTc-Dextran 40 was > 95%. 99mTc-Dextran 40 could drainage into first, second, and third lymph node and the radioactive lymph node could be detected by the  detector in the animal experiment. After 99mTc-Dextran 40 injecting into intraparenchyma, 50.0% cases (15/30) were identified the drainage lymphatic vessels and radioactive IMLNs by SPECT. The drainage lymphatic vessel was found from injection point to the first IMLN (IM-SLN) after 10.5±0.35 minutes radiotracer injection, and then 99mTc-Dextran 40 was accumulated into the IM-SLN. The combination imaging of SPECT/CT showed the second IMLN received the lymph drainage from the IM-SLN. The lymphatic drainage was step by step in the internal mammary area. Conclusion The lymph was identified to drain from different regions of the breast to IM-SLN, and then outward from IM-SLN to other IMLN consecutively. It demonstrated the concept of the IM-SLN and provided more evidences for the application of internal mammary sentinel lymph node biopsy.

Simulation Analysis of Cylinder Impact Performance Influenced by Shaft Sleeve Structure

Cong Liu,Pei Xiao,Xingli Li,Gangyan Li 한국유체기계학회 2018 International journal of fluid machinery and syste Vol.11 No.1

To study the cylinder motion characteristics, cylinder and shaft sleeve stress characteristics of cylinder stroke and return process influenced by different shaft sleeve structure, the cylinders with non-chamfering shaft sleeve, C0.3 chamfering shaft sleeve and R0.3 round corner shaft sleeve were used for simulation of cylinder stroke and return process. The results show that the piston velocity curves of three kinds of shaft sleeve are identical. Maximum stress of different shaft sleeves fluctuates and maximum stress elements of C0.3 and R0.3 shaft sleeve are similar. When cylinder strokes, maximum stress of cylinder occurs at the end of piston rod connected to the load; the stress of C0.3 shaft sleeve is the lowest. When cylinder returns, maximum stress of cylinder occurs at the shaft sleeve; the stress of C0.3 and R0.3 shaft sleeve differ little and are both lower than that of non-chamfering shaft sleeve. It provides a reference for structure optimization and service life improvement of the cylinder shaft sleeve.

RESULTS ON MEROMORPHIC FUNCTIONS SHARING THREE VALUES WITH THEIR DIFFERENCE OPERATORS

LI, XIAO-MIN,YI, HONG-XUN,KANG, CONG-YUN Korean Mathematical Society 2015 대한수학회보 Vol.52 No.5

Under the restriction of finite order, we prove two uniqueness theorems of nonconstant meromorphic functions sharing three values with their difference operators, which are counterparts of Theorem 2.1 in [6] for a finite-order meromorphic function and its shift operator.