A5101846230- Ultrasonics and Acoustic Wave Propagation
- Structural Health Monitoring Techniques
- Non-Destructive Testing Techniques
- Geophysical Methods and Applications
- Probabilistic and Robust Engineering Design
- Numerical methods in inverse problems
- Thermography and Photoacoustic Techniques
- Microwave Imaging and Scattering Analysis
- Acoustic Wave Phenomena Research
- Engineering Applied Research
- Railway Engineering and Dynamics
- Covalent Organic Framework Applications
- Acoustic Wave Resonator Technologies
- Technology Assessment and Management
- Metal-Organic Frameworks: Synthesis and Applications
- Composite Structure Analysis and Optimization
- Luminescence Properties of Advanced Materials
- Seismic Performance and Analysis
- MXene and MAX Phase Materials
- Structural Load-Bearing Analysis
- Material Properties and Processing
- Membrane Separation and Gas Transport
- Ferroelectric and Negative Capacitance Devices
- Catalysis for Biomass Conversion
- Flow Measurement and Analysis
Dong-A University
2013-2024
GS Caltex (South Korea)
2024
Nexen (Canada)
2022
Korea Institute of Materials Science
2021-2022
Pusan National University
2022
Seoul National University
1999-2020
Korea Advanced Institute of Science and Technology
2007-2019
Lotte Fine Chemical (South Korea)
2017-2019
Chung-Ang University
2017-2019
University of Seoul
2015
Abstract This paper presents a new class of displacement reconstruction scheme using only acceleration measured from structure. For given set data, the problem is formulated as boundary value in which approximated by second‐order central finite difference displacement. The reconstructed minimizing least‐squared errors between and within time interval. An overlapping window introduced to improve accuracy becomes ill‐posed because conditions at both ends each are not known priori ....
A damage detection technique, which does not rely on any past baseline signals, is proposed to assess in composite plates by using an enhanced time reversal method. concept of modern acoustics has been adapted guided-wave propagation improve the detectability local defects structures. In particular, wavelet-based signal processing techniques have developed enhance reversibility Lamb waves thin laminates. method, input at excitation point can be reconstructed if a response measured another...
Many applications, most notably memory and optical devices use ferroelectric materials. For many years the evolution of field has revolved around understanding materials science behind complex structures like artificial superlattices based mainly on perovskite-structure oxides. The recent discovery ferroelectricity in fluorite-structure oxides opened a new research direction. However, formation unstable or metastable phases atomic layer deposited fluorite inhibited full origin these This...
A structural health monitoring system is developed for continuous online of delamination initiation and growth in composite structures. Structural problems are often cast the context a statistical pattern recognition paradigm, which damage state structure inferred by comparing test data with baseline data. However, subtle signal changes due to can be masked larger ambient variation operational environmental conditions an in-service structure. Therefore, it critical development robust...
We prepared an Au NP loaded microporous polymer using the thiol–yne reaction and <italic>in situ</italic> reduction reaction, investigated its catalytic activity.
Ferroelectric Hf0.5Zr0.5O2 (HZO) films were grown by the atomic layer deposition (ALD) technique on an ALD or physical-vapor-deposited (PVD, sputtering) TiN bottom electrode (BE). The PVD film showed small grains with flat surface morphology, mainly consisting of (111) crystallographic plane. In contrast, exhibited a larger diameter and faceted grain shapes, (200) planes. 10-nm-thick HZO BE lower internal field, enhanced endurance (&gt;1 × 1010 cycle at 2.5 MV/cm), decreased leakage...
In this article, a conceptual process design for the production of lactide is proposed, where an one-step gas phase synthesis route adopted. Then, proposed evaluated and compared with conventional two-step (polycondensation depolymerization) process. Specifically, techno-economic analysis life cycle are performed to compare both processes in terms conversion cost global warming potential, respectively, examine sustainable capability At lactic acid feed supply rate 20 ton/h, was $37.57/ton...
The autogenous manual gas tungsten arc welding (GTAW) process was used for cladding austenitic stainless steel 316L using a single pass with various contact tip-to-work distances (CTWDs). Immersion and electrochemical tests were to evaluate the corrosion resistance of welded specimens, microstructural analysis conducted investigate chemical composition molten pool heat-affected zone welding. key findings this study indicate that improved under CTWD 5 mm due optimal distribution ferrite...
Abstract This paper presents a geometric mean scheme (GMS) to determine an optimal regularization factor for Tikhonov technique in the system identification problems of linear elastic continua. The characteristics non‐linear inverse and role are investigated by singular value decomposition sensitivity matrix responses. It is shown that results solution generalized average between priori estimates posteriori solution. Based on this observation, defined as maximum minimum validity GMS...
This paper presents a system identification scheme to determine the geometric shape of an inclusion in finite body. The proposed algorithm is based on minimization least-squared errors between measured displacement field and calculated by element model. domain parameterization technique adopted manipulate variation inclusion. To stabilize optimization process, new regularization function defined length boundary curve added error function. A variable factor for consistent effect. modified...
An economically efficient one-step lactide synthesis process has been developed by using a low-price commercialized catalyst of SiO2/Al2O3 in packed-bed reactor. Under the optimized conditions preheater temperature 160 °C, reactor 240 and WHSV 3 h–1, 90% lactic acid conversion 99% selectivity were obtained. Filling glass beads underneath bed proved to be quite effective improving reaction performance. The stably maintained its activity for as long 120 h showing no noticeable changes...
Abstract This paper presents a new class of regularization functions and the associated scheme for structural system identification. In particular, 1‐norm are investigated to overcome smearing effect 2‐norm identification discontinuous parameters structures. The truncated singular value decomposition is employed filter out noise‐polluted solution components impose function on SI. bilinear fitting method proposed selecting an optimal truncation number decomposition. validity demonstrated...
We synthesized a Yb(III)-incorporated microporous polymer (Yb-ADA) and studied its gas adsorption property catalytic activity. The adamantane-based porous (ADA) was obtained from an ethynyl-functionalized adamantane derivative 2,5-dibromoterephthalic acid through Sonogashira–Hagihara cross-coupling. ADA had two carboxyl groups which were used for Yb(III) coordination under basic conditions. Brunauer-Emmett-Teller (BET) surface area of 970 m2 g−1. As ions incorporated into ADA, the reduced to...