A5088339977- Vibration Control and Rheological Fluids
- Hydraulic and Pneumatic Systems
- Structural Engineering and Vibration Analysis
- Seismic Performance and Analysis
- Vehicle Dynamics and Control Systems
- PAPR reduction in OFDM
- Wireless Communication Networks Research
- Effects of Vibration on Health
- Vibration and Dynamic Analysis
- Elevator Systems and Control
- Cooperative Communication and Network Coding
- Cognitive Radio Networks and Spectrum Sensing
- Advanced X-ray and CT Imaging
- Iterative Learning Control Systems
- Advanced MIMO Systems Optimization
- Advanced Sensor and Control Systems
- Medical Imaging Techniques and Applications
- Advanced MEMS and NEMS Technologies
- Radiation Dose and Imaging
- Obesity, Physical Activity, Diet
- Dielectric materials and actuators
- Shape Memory Alloy Transformations
- Engineering Applied Research
- Advanced Wireless Network Optimization
- Satellite Communication Systems
Hanwha Solutions (South Korea)
2018-2022
Yonsei University
2015-2020
Peking University
2020
National Clinical Research Center for Digestive Diseases
2020
Stomatology Hospital
2020
Inha University
2014-2019
Zhengzhou University
2016-2018
Agency for Defense Development
2018
Shenzhen Luohu People's Hospital
2018
Shenzhen University
2018
In this research, a two-core type of semi-active magnetorheological (MR) damper is designed for an airplane landing gear system, and its efficiency evaluated using two different controllers. Firstly, MR on the basis dynamic properties commercial oleo-pneumatic passive damper. To satisfy fail-safe condition damper, orifices are used to provide asymmetry via recoil valve. Second, in order evaluate efficiency, equation motion model with derived, controllers formulated: skyhook controller hybrid...
Qian H, Zhao Y, Peng Han C, Li S, Huo N, Ding Duan Xiong L, Sang H. Activation of cannabinoid receptor CB2 regulates osteogenic and osteoclastogenic gene expression in human periodontal ligament cells. J Periodont Res 2010; 45: 504–511. © 2010 John Wiley & Sons A/S Background Objective: Cannabinoid CB2, expressed osteoblasts osteoclasts, plays a crucial role the regulation bone metabolism. Since (PDL) cells can differentiate into osteoblasts, this study was undertaken to investigate effect...
In this research, a new type of magnetorheological (MR) damper, applicable to the landing gear system airplanes, is presented. As first step, an oleo-pneumatic which used for small adopted. Its damping force tested determine principal design parameters proposed MR damper. Thereafter, structural configuration damper characterized according operating principles adopted The has two orifices and recoil valve where one orifice be controlled by flow direction. An analytical model field-dependent...
In cognitive radio (CR) ad-hoc network, the characteristics of frequency resources that vary with time and geographical location need to be considered in order efficiently use them. Environmental statistics, such as an available transmission opportunity data rate for each channel, system requirements, specifically desired rate, can also change location. multi-band operation, primary activity usable bandwidth are different band. this paper, we propose a Q-learning-based dynamic optimal band...
To investigate the characteristics and molecular events of dental pulp stem cells (DPSCs) for tissue regeneration with aging, we isolated analyzed from human exfoliated deciduous teeth (SHED) permanent young (Y-DPSCs) old (A-DPSCs) adults. Results showed that stemness osteogenic differentiation capacity DPSCs decreased aging. The RNA sequencing results glycine, serine, threonine metabolism was one most enriched gene clusters among SHED, Y-DPSCs, A-DPSCs, according to analysis based on Kyoto...
This work proposes a novel type of tunable magnetorheological (MR) damper operated based solely on the location permanent magnet incorporated into piston. To create larger damping force variation in comparison with previous model, different design configuration permanent-magnet-based MR (PMMR) is introduced to provide magnetic flux dispersion two circuits by utilizing materials reluctance. After discussing and some advantages newly designed mechanism, principle analyzed through both...
A direct-drive valve (DDV) system is a kind of electrohydraulic servo system, in which the actuator directly drives spool valve. In conventional DDV systems, generally driven by an electromagnetic actuator. Performance characteristics such as frequency bandwidth systems are limited due to response property. order improve performance this work new configuration for actuated piezostack with flexible beam mechanism proposed (in short, piezo-driven system). Its benefits demonstrated through both...
In this research, a new type of magnetorheological damper for small-sized aircraft landing gear system is proposed and its performance evaluated with respect to design parameters the magnetic core. As first step, configuration system, which consists orifices, recoil valve, circuits, introduced working principles. After formulating governing equations motion, six different models featuring number core pole length are chosen investigate both stability efficiency. Subsequently, distribution...
Abstract Magnetorheological fluids (MRF) that undergo a change in their viscoelastic properties under the magnetic fields have been considered as one of most important smart functional materials for vibration dampers and shock absorbers several engineering applications. However, use magnetorheological practical applications has limited by poor sedimentation ratio on-state yield stress. Herein, we report hybrid rGO-MoS 2 additives high-performance fluid. Two different kinds additives, which...
Summary In cognitive radio (CR) networks, secondary users should effectively use unused licensed spectrums, unless they cause any harmful interference to the primary users. Therefore, spectrum sensing and channel resource allocation are 2 main functionalities of CR which play important roles in performance a system. To maximize system utility, we propose joint out‐of‐band operating scheme based on genetic algorithm for frequency hopping–based networks. this paper, sense signal hopping...
This paper experimentally investigates the control performances of a piezostack actuator direct-drive valve (PADDV) operating at high temperatures. In this study, PADDV system is designed based on special specifications featuring temperature (150 °C) and wide bandwidth (200 Hz). After manufacturing with design limitations such as size maximum input voltage to actuator, displacement spool located inside system, which directly related flow rate, controlled several different temperatures motion...
We propose a multi-pass approach to reduce cone-beam artifacts in circular orbit computed tomography (CT) system. Employing large 2D detector array reduces the scan time but produces Feldkamp, Davis, and Kress (FDK) reconstruction because of insufficient sampling for exact reconstruction. While two-pass algorithm proposed by Hsieh is effective at reducing artifacts, correction performance degraded when bone density moderate cone angle large. In this work, we treated generated from soft...
This technical note presents control performances of a piezoactuator direct drive valve (PDDV) operated at high temperature environment. After briefly discussing operating principle and mechanical dimensions the proposed PDDV, an appropriate size PDDV is manufactured. As first step, effect on performance experimentally investigated by measuring spool displacement various temperatures. Subsequently, thermally insulated using aerogel installed in large-size heat chamber which...
In this study, a semi-active magneto-rheological (MR) mount is designed and manufactured to minimize unwanted vibrations for the cabin of heavy vehicles. Normally, working conditions in vehicles are extremely rugged. Usually, use passive rubber mounts reduction from road. However, has definite performance limitations because fixed resonance frequency when design finished. An MR application one solutions viscosity fluid can be controlled. As first step, an experimental apparatus was...
In this study, experiments are conducted to evaluate dynamic characteristics and position tracking control performance of a piezoelectric actuator at various temperature conditions including up 180 °C. An experimental apparatus consisting heat chamber, piezostack actuator, laser sensor, gap data acquisition board, function generator computer is established. To obtain the commercial desired input signals, which sinusoidal waveforms with several different frequencies, generated by generator,...
In this study, the dynamic characteristics of passive mounts and a semi-active magneto-rheological (MR) mount for vibration attenuation wheel loader cabin are experimentally evaluated. First, design procedures two different described, principal parameters such as stiffness determined from simple but practically feasible model. Then, with material manufactured tested. Secondly, MR is designed based on field-dependent yield stress fluid. A prototype then considering flow paths: annular path...
In this paper, a novel single-stage valve system activated by piezostack actuator is proposed and experimentally evaluated at both room temperature (20 °C) high (100 conditions. A hinge-lever displacement amplifier adopted in the to magnify generated from actuator. After explaining operating principle of piezostack-driven system, geometric dimensions mechanical properties components are discussed details. An experimental apparatus then manufactured evaluate performances such as flow rate....
This paper presents tracking control performances of a piezostack direct drive valve (PDDV) operated at various temperatures. As afirst step, spool and system are designed by the piezoactuator. After briefly describing about operating principle, an experimental apparatus to investigate effect temperaturs on is set up. Subsequently, PDDV installed in large-size heat chamber equipped with electric circuits sensors. A classical proportional-integral-derivative (PID) controller applied...
The aim of this study was to investigate the differentiation potential adipose-derived mesenchymal stem cells (ADMSCs) into osteoblasts by human bone morphogenetic protein-7 (hBMP-7) induction. ADMSCs were isolated from subcutaneous adipose tissue a rabbit, and then transfected with pcDNA3.1 vector alone pcDNA3.1-hBMP-7 (hBMP-7), respectively. Untransfected used as control group. After transfection, morphology green fluorescent protein (GFP) fluorescence intensity observed microscopy....
This paper proposes a new inkjet printing system based on the electrohydrodynamic (EHD) method, and its performances are experimentally evaluated using copper nano-sized particles ink. After briefly explaining working principle of proposed system, both static dynamic characteristics frame structures investigated to ensure structural stability. Then, principal components such as laser sensor calibrated reduce position error. Subsequently, metal inks featuring prepared ultrasonic homogenizer...