Forced Vibration Equation and Vehicle–Bridge Coupling Analysis of Composite Trough Girder with Corrugated Steel Webs

Yongming Xiong,Ming Yang,Linjie Tian,Ziye Yang 대한토목학회 2024 KSCE Journal of Civil Engineering Vol.28 No.7

The Trough Girder with Corrugated Steel Webs (TGCWs) represents a novel form of through bridge that offers improved stress distribution characteristics and decreased inherent flaws when compared to the traditional trough girder design. Although the static behaviors of TGCWs have been reported before, the dynamic properties of this new structure have been rarely studied, especially under loading. In this paper, the shear lag effect of the bottom flange of TGCWs, and the stiffness correction of CSWs, the analytical equations of natural frequencies and forced vibration were deduced by considering the shear deformation of the TGCWs. The commercial finite element software ABAQUS and multibody system software SIMPACK were integrated to verify the correctness of theoretical values. In comparison to the Chinese design code, the derived analytical equation was more precise. Based on the findings of parameter analysis, it is recommended to construct the TGCWs bridge within a range of 25 m − 35 m and to control the velocity of trains at roughly 100 km/h or 150 km/h.

전라남도 노인공동생활가정의 물리적 주거생활환경 개선에 관한 연구

양영명(Yang Yongming),정금호(Kum-Ho Chung) 한국주거학회 2018 한국주거학회 학술대회논문집 Vol.30 No.2

Housing is a container for human daily life, and it is the most basic environment that has been created to achieve the quality of life, also it has a greater significance to the elderly than the ordinary public. Elderly residential welfare facilities are divided into nursing homes, elderly group-home in partnership, and welfare facilities. This subject focused at all the elderly group-home live in Jeollanamdo. The elderly group-home improment plans by analyze the architectural characteristics, safety, convenience, and comfort of residential environment. This subject were based on actual surveys from September 27, 2018 to October 5, 2018. The results of the survey and research are as bellows. First, the security and convenience of access to rooms space needs to be improved. Second, for an elderly person with physical activity, the toilet and the safety features (none-slip tread, emergency bell) need to be improved. Third, considering the elderly with poor mobility and adaptability, the connection of each space needs to be accessible. Fourth, given the convenience of the facility, the handle of the doors and windows needs to be adjusted so that it can be used. Fifth, the lighting in the bedroom is directly related to the health of the elderly, so it needs to head the south. Sixth, the colour of the elderly living space planning needs to be improved.

Jumping motion planning for biped robot based on hip and knee joints coordination control

Yongming Bian,Jie Shao,Jixiang Yang,Ao Liang 대한기계학회 2021 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.35 No.3

This paper proposes a method of hip and knee joints coordination control planning based on virtual force. Firstly, the kinematic model of biped robot is established according to the physiological structure of human body. Secondly, the kinematics equation is established based on the jumping motion characteristics of the hip and knee joints, and the motion angles and angular velocities of the hip and knee joints are solved by inverse kinematics. Then, in order to optimize the motion posture, balance the driving power of the joints, and reduce the driving burden of the knee joint, a coordinated hip-knee joint control strategy and its implementation method for biped robot jumping motion are proposed based on virtual force control method. Finally, the effectiveness of the proposed method is verified by comparing and analyzing the simulation data of biped robot with the measurement data of human motion.

Fabrication and dielectric properties of CCTO/PF dielectric composites: CCTO with different particle size

Yang Zhao,Yuzhen Zhao,Yuhua Niu,Yongming Zhang,Zongcheng Miao 한양대학교 세라믹연구소 2020 Journal of Ceramic Processing Research Vol.21 No.3

Calcium copper titanate (CaCu3Ti4O12, CCTO) particles with three types of particle size (CCTO–i, CCTO–ii, CCTO–iii) areprepared by wet chemical method. And then the dielectric composites based on CCTO particles and Phenol formaldehyderesin (PF) are fabricated by mixing and mould pressing. This paper mainly studies the microstructure and dielectric propertiesof CCTO/PF dielectric composites (CCTO–i, CCTO–ii and CCTO–iii composites). XRD, FTIR and SEM indicate that theCCTO particles are dispersed in the polymer matrix. In addition, the effect of particle size on the dielectric properties ofCCTO/PF composites is also discussed. By comparing the CCTO/PF composites with different particle sizes, it is found thatthe CCTO–i composite has a high maximum dielectric constant and low loss at room temperature of 100 Hz, while the CCTOvolume fraction was 0.5 in the measurement frequency range, which shows a very weak frequency dependence. On this basis,the CCTO–i composite with relatively small particle size has excellent dielectric properties, which may imply that the effectof interface will be changed by smaller particle size.

Vibration Analysis of Transformer DC bias Caused by HVDC based on EMD Reconstruction

Liu, Xingmou,Yang, Yongming,Huang, Yichen The Korean Institute of Electrical Engineers 2018 Journal of Electrical Engineering & Technology Vol.13 No.2

This paper proposes a new approach utilizing empirical mode decomposition (EMD) reconstruction to process vibration signals of a transformer under DC bias caused by high voltage direction transmission (HVDC), which is the potential cause of additional vibration and noise from transformer. Firstly, the Calculation Method is presented and a 3D model of transformer is simulated to analyze transformer deformation characteristic and the result indicate the main vibration is produced along axial direction of three core limbs. Vibration test system has been built and test points on the core and shell of transformer have been measured. Then, the signal reconstruction method for transformer vibration based on EMD is proposed. Through the EMD decomposition, the corrupted noise can be selectively reconstructed by the certain frequency IMFs and better vibration signals of transformer have been obtained. After EMD reconstruction, the vibrations are compared between transformer in normal work and with DC bias. When DC bias occurs, odd harmonics, vibration of core and shell, behave as a nonlinear increase and the even harmonics keep unchanged with DC current. Experiment results are provided to collaborate our theoretical analysis and to illustrate the effectiveness of the proposed EMD method.

Numerical Research of High-Voltage Conductors: Electric Field Characteristics in Ice-Covered Spaces

Liu Xingmou,Yang Hui,Gu Yan,Li Lei,Yang Yongming,Jadoon Ammad,Sun Xun,Xu Jun 대한전기학회 2024 Journal of Electrical Engineering & Technology Vol.19 No.5

The icing of overhead high-voltage transmission lines not only caused accidents such as line dance down pole and fl ashover, but also lead to abnormal fi eld strength on the line surface and distortion of electric fi eld distribution, which threatens the normal operation of the power system. On 500KV transmission lines, a numerical model of the ice cover conductor considering the dielectric properties of the ice layer was established, considering the infl uence of the spacer strip. The local spatial electric fi eld distribution inside and on the surface of the ice sheet under diff erent ice cover severity was studied. The numerical calculation results showed that the electric fi eld variation inside the ice sheet was amplifi ed, and the electric fi eld distortion rate in the ice cover case was larger than that in the ice-free case at the spacer strip, and both are larger than 150%. In the crescent-shaped transit ice, the aberration rate at the spacer bar inside the crescent-shaped ice decreases with the extension of the crescent-shaped ice, and the electric fi eld aberration rate at the surface of the icicle in the overhanging transit ice was about 20%. The study showed that ice with diff erent characteristics had a signifi cant eff ect on the electric fi eld around transmission lines, and the study of high-voltage transmission lines over ice could introduce changes in the electric fi eld.

Smoke detection in video sequences based on dynamic texture using volume local binary patterns

( Gaohua Lin ),( Yongming Zhang ),( Qixing Zhang ),( Yang Jia ),( Gao Xu ),( Jinjun Wang ) 한국인터넷정보학회 2017 KSII Transactions on Internet and Information Syst Vol.11 No.11

In this paper, a video based smoke detection method using dynamic texture feature extraction with volume local binary patterns is studied. Block based method was used to distinguish smoke frames in high definition videos obtained by experiments firstly. Then we propose a method that directly extracts dynamic texture features based on irregular motion regions to reduce adverse impacts of block size and motion area ratio threshold. Several general volume local binary patterns were used to extract dynamic texture, including LBPTOP, VLBP, CLBPTOP and CVLBP, to study the effect of the number of sample points, frame interval and modes of the operator on smoke detection. Support vector machine was used as the classifier for dynamic texture features. The results show that dynamic texture is a reliable clue for video based smoke detection. It is generally conducive to reducing the false alarm rate by increasing the dimension of the feature vector. However, it does not always contribute to the improvement of the detection rate. Additionally, it is found that the feature computing time is not directly related to the vector dimension in our experiments, which is important for the realization of real-time detection.

Prediction of Pharmacokinetics and Penetration of Moxifloxacin in Human with Intra-Abdominal Infection Based on Extrapolated PBPK Model

Zhu, LiQin,Yang, JianWei,Zhang, Yuan,Wang, YongMing,Zhang, JianLei,Zhao, YuanYuan,Dong, WeiLin The Korean Society of Pharmacology 2015 The Korean Journal of Physiology & Pharmacology Vol.19 No.2

The aim of this study is to develop a physiologically based pharmacokinetic (PBPK) model in intra-abdominal infected rats, and extrapolate it to human to predict moxifloxacin pharmacokinetics profiles in various tissues in intra-abdominal infected human. 12 male rats with intra- abdominal infections, induced by Escherichia coli, received a single dose of 40 mg/kg body weight of moxifloxacin. Blood plasma was collected at 5, 10, 20, 30, 60, 120, 240, 480, 1440 min after drug injection. A PBPK model was developed in rats and extrapolated to human using GastroPlus software. The predictions were assessed by comparing predictions and observations. In the plasma concentration versus time profile of moxifloxcinin rats, $C_{max}$ was $11.151{\mu}g/mL$ at 5 min after the intravenous injection and $t_{1/2}$ was 2.936 h. Plasma concentration and kinetics in human were predicted and compared with observed datas. Moxifloxacin penetrated and accumulated with high concentrations in redmarrow, lung, skin, heart, liver, kidney, spleen, muscle tissues in human with intra-abdominal infection. The predicted tissue to plasma concentration ratios in abdominal viscera were between 1.1 and 2.2. When rat plasma concentrations were known, extrapolation of a PBPK model was a method to predict drug pharmacokinetics and penetration in human. Moxifloxacin has a good penetration into liver, kidney, spleen, as well as other tissues in intra-abdominal infected human. Close monitoring are necessary when using moxifloxacin due to its high concentration distribution. This pathological model extrapolation may provide reference to the PK/PD study of antibacterial agents.

Vibration Analysis of Transformer DC bias Caused by HVDC based on EMD Reconstruction

Xingmou Liu,Yongming Yang,Yichen Huang 대한전기학회 2018 Journal of Electrical Engineering & Technology Vol.13 No.2

This paper proposes a new approach utilizing empirical mode decomposition (EMD) reconstruction to process vibration signals of a transformer under DC bias caused by high voltage direction transmission (HVDC), which is the potential cause of additional vibration and noise from transformer. Firstly, the Calculation Method is presented and a 3D model of transformer is simulated to analyze transformer deformation characteristic and the result indicate the main vibration is produced along axial direction of three core limbs. Vibration test system has been built and test points on the core and shell of transformer have been measured. Then, the signal reconstruction method for transformer vibration based on EMD is proposed. Through the EMD decomposition, the corrupted noise can be selectively reconstructed by the certain frequency IMFs and better vibration signals of transformer have been obtained. After EMD reconstruction, the vibrations are compared between transformer in normal work and with DC bias. When DC bias occurs, odd harmonics, vibration of core and shell, behave as a nonlinear increase and the even harmonics keep unchanged with DC current. Experiment results are provided to collaborate our theoretical analysis and to illustrate the effectiveness of the proposed EMD method.

Effects of dye etching on the morphology and performance of ZnO nanorod dye-sensitized solar cells

Yu Lin,Jiyuan Yang,Yongming Meng 한국화학공학회 2013 Korean Journal of Chemical Engineering Vol.30 No.11

Dye-sensitized solar cells based on electrodeposited ZnO nanorod arrays were fabricated and tested. Fieldemission scanning electron microscopy (FESEM) and X-ray powder diffraction (XRD) were used to identify the characters of ZnO nanorod arrays. The effects of dye etching on the morphology and performance of ZnO nanorod dye-sensitized solar cells were studied. It was found that the surfaces of ZnO nanorods were both etched by dye solutions, no matter N3 or N719. Compared with N3, N719 had a larger damage to the structure of ZnO nanorod photoanode, and the photoelectric conversion efficiency of cells decreased quickly with the sensitizing time increasing. In a certain range, the increasing length of ZnO nanorods can clearly improve the photoelectric conversion efficiency of cells.