A5019813726- Ferroelectric and Piezoelectric Materials
- Acoustic Wave Resonator Technologies
- Multiferroics and related materials
- Engineering Applied Research
- Non-Destructive Testing Techniques
- Ultrasonics and Acoustic Wave Propagation
- Microwave Dielectric Ceramics Synthesis
- Railway Engineering and Dynamics
- Welding Techniques and Residual Stresses
- Brake Systems and Friction Analysis
- Seismic Waves and Analysis
- Seismic Imaging and Inversion Techniques
- Diverse Approaches in Healthcare and Education Studies
- Gut microbiota and health
- Probiotics and Fermented Foods
- Food Quality and Safety Studies
- Advanced MEMS and NEMS Technologies
- Regional Development and Environment
- Diverse Topics in Contemporary Research
- Effects and risks of endocrine disrupting chemicals
- Educational Reforms and Innovations
- Education, Safety, and Science Studies
- Internet of Things and Social Network Interactions
- Medical Research and Treatments
- CCD and CMOS Imaging Sensors
Sun Moon University
2015-2024
Ceracomp (South Korea)
2009-2024
Seoul National University
2001-2024
Samsung (South Korea)
2021-2023
Inha University
2005-2023
Pohang University of Science and Technology
2018-2023
Korea Electric Power Corporation (South Korea)
2023
Pusan National University
2019-2023
Korea Aerospace Research Institute
2022
Korea Railroad Research Institute
2007-2021
Piezoelectric materials are essential parts of the electronics and electrical equipment used for consumer industrial applications, such as ultrasonic piezoelectric transducers, sensors, actuators, transformers, resonators. In this review, development figures merit various electromechanical applications surveyed, focusing on crystals, i.e., high-performance relaxor-PbTiO3-based perovskite ferroelectric crystals nonferroelectric high-temperature crystals. The uniqueness these is discussed with...
Electronically controlled air suspension systems have been used in vehicles to improve ride comfort and handling safety by adjusting vehicle height. This paper proposes a new nonlinear controller adjust the height of sprung mass (height control) regulate roll pitch angles body (leveling an system. A sliding mode control algorithm is designed tracking accuracy overcome nonlinearities uncertainties mathematical model system formulated affine form describe dynamic behavior derive algorithm. The...
To interpret subsurface structures properly, elastic wave propagation must be considered. Because media are described by more parameters than acoustic media, waveform inversion is likely to affected local minima inversion. In a conventional inversion, P- and S-wave velocities properly recovered, whereas density difficult reconstruct. For this reason, most full-waveform studies assume that fixed. Although several algorithms have been developed attempt describe their results still not...
To describe subsurface structures in anisotropic media properly, particularly transversely isotropic with a vertical symmetry axis (VTI), which frequently appear sedimentary basin environments, we develop frequency-domain elastic full waveform inversion algorithm for 2-D VTI media. The is based on the cell-based finite-difference modelling method and adjoint state of wave equation.
Accurate pollutant prediction is essential in fields such as meteorology, meteorological disasters, and climate change studies. In this study, long short-term memory (LSTM) deep neural network (DNN) models were applied to six pollutants comprehensive air-quality index (CAI) predictions from 2015 2020 Korea. addition, we used the method find best data sources that provide factors affecting behaviors. This study had two steps: (1) predicting pollutants, including fine dust (PM10), particulate...
Nanobubbles (NBs) have a widespread application in antimicrobial activity, wastewater treatment, and ecological restoration due to numerous peculiar characteristics, such as small diameter, long-term stability, ability produce hydroxyl radicals. Despite significant applications, only limited comprehensive investigations are available on the role of surfactants pH NBs characteristics. Therefore, this study examines effects different (i.e., anionic, cationic, nonionic) medium bulk NB...
Riverine wetlands are reservoirs of biodiversity and provide various ecological functions, including carbon absorption. However, they have been subjected to continuous degradation loss due river management practices focused on irrigation flood control. This study aims quantify the absorption capacity riverine propose strategies for their restoration management. To achieve this, a laboratory-scale wetland model was developed, rates were analyzed under varying hydrological conditions. The...
Compound drought-wildfire event is increasing trend in its frequency and severity worldwide, driven by the interaction between drought wildfire, as seen 2017 California wildfires 2019-20 Australian wildfires. However, there still lack of a methodology to quantitatively estimate risk compound disaster. Therefore, this study presents disaster using Drought scenario based Fire Weather Index (DFWI) projects future on Social Shared Pathway (SSP) climate change scenarios. Gyeongsangbuk-do province...
Three types of piezoelectric single crystals [PMN-PT (Generation I [Pb(Mg1/3Nb2/3)O3-PbTiO3]), PMN-PZT II [Pb(Mg1/3Nb2/3)O3-Pb(Zr,Ti)O3]), PMN-PZT-Mn III)] were grown by the solid-state crystal growth (SSCG) method, and their dielectric properties measured compared. Compared to (001) PMN-PT crystals, exhibited a higher transition temperature between rhombohedral tetragonal phases (TRT = 144°C), as well coercive electric field (EC 6.3 kV/cm) internal bias (EI 1.6 kV/cm). The (011) showed...
Review article of the solid-state crystal growth (SSCG) technique and progress lead-free ferroelectric single crystals for piezoelectric applications.
The evolution of 3D depth-sensing technology enables various applications in mobile devices, from conventional photography enhancement (e.g., autofocus and bokeh effect) to new such as augmented reality scanning. Usually, depth sensors operate with RGB color for image fusion; the spatial resolution should be compatible that better fusion quality, which requires mega-pixel sensors. Among different techniques, only indirect time-of-flight (ToF) can generate higher maps smaller system cost...
Thermal stabilities of relaxor-PbTiO3 single crystals are great importance due to their limited operational temperatures in devices. Herein, elucidate how poling conditions influence thermal stabilities, we investigated direct current (DC) and alternating (AC) poled Pb(Mg1/3Nb2/3)O3-0.29PbTiO3 (PMN-29PT) grown by solid-state crystal growth, which guarantees more compositional uniformity. Our experiments show that the dielectric permittivity DC AC 3560 4970, respectively, after annealing at...
Piezoelectric ceramic with a composition of (94 − x)(Na1/2Bi1/2)TiO3-6BaTiO3−x(K1/2Na1/2)NbO3 (NBT-BT-xKNN) is promising lead-free piezoelectric material for actuator applications because its giant electric-field-induced strains, which are comparable that soft Pb(ZrxTi1−x)O3 (PZT) ceramics. Using the solid-state single crystal growth method, we succeeded in fabricating usable crystals NBT-BT-3KNN (6 mm × 6 8 size) uniform chemical composition. The room temperature properties ⟨001⟩, ⟨110⟩,...
We have developed a reflection-mode switchable subwavelength Bessel-beam (BB) and Gaussian-beam (GB) photoacoustic microscopy (PAM) system. To achieve both high resolution, we tightly attached very small ultrasound transducer to an optical objective lens with numerical aperture of 1.0 working distance 2.5 mm. used axicon achromatic doublet in our system obtain the extended depth field (DOF) BB. compare DOF performance achieved BB-PAM against GB-PAM system, designed so that GB can be easily...
Aimed at developing lead-free magnetoelectric (ME) composites with performances as good lead (Pb)-based ones, this study employed (001) and (011) oriented 82BaTiO3-10BaZrO3-8CaTiO3 (BZT–BCT) piezoelectric single crystals, fabricated by the cost-effective solid-state crystal growth (SSCG) method, in combination inexpensive, magnetostrictive base metal Nickel (Ni). The off-resonance, direct ME coupling prepared Ni/BZT–BCT/Ni laminate was found to be strongly dependent on crystallographic...