A5101656426- Photonic and Optical Devices
- Advanced Fiber Optic Sensors
- Plasmonic and Surface Plasmon Research
- Vestibular and auditory disorders
- Advanced Photonic Communication Systems
- Photonic Crystals and Applications
- Semiconductor Lasers and Optical Devices
- Robotics and Sensor-Based Localization
- Electronic Packaging and Soldering Technologies
- Optical Coatings and Gratings
- Robotic Path Planning Algorithms
- 3D IC and TSV technologies
- Ophthalmology and Eye Disorders
- Advanced Fiber Laser Technologies
- Advanced biosensing and bioanalysis techniques
- Intermetallics and Advanced Alloy Properties
- Gold and Silver Nanoparticles Synthesis and Applications
- Semiconductor materials and interfaces
- Optical Network Technologies
- Lignin and Wood Chemistry
- Wood Treatment and Properties
- Full-Duplex Wireless Communications
- Masonry and Concrete Structural Analysis
- Thermochemical Biomass Conversion Processes
- Glaucoma and retinal disorders
Seoul National University Bundang Hospital
2023-2025
Hallym University
2022-2024
Hallym University Medical Center
2024
Seoul National University
2021-2023
Soonchunhyang University Hospital
2011-2022
Bucheon University
2022
Chung-Ang University
2008-2019
Soonchunhyang University
2018
Pohang University of Science and Technology
2007-2011
Hanbat National University
2004-2006
Abstract This study investigated the feature importance of near-infrared spectra from random forest regression models constructed to predict carbonization characteristics hydrochars produced by hydrothermal kraft lignin. The model achieved high coefficients determination 0.989, 0.988, and 0.985 with root mean square errors 0.254, 0.003, 0.008 when predicting carbon content, atomic O/C ratio, H/C respectively. outperformed multilayer perceptron for all predictions. In analysis, spectral...
This paper presents a sensor-based online coverage path planning algorithm guaranteeing complete of unstructured planar environments by mobile robot. The proposed abstracts the environment as union robot-sized cells and then uses spiral filling rule. It can be largely classified an approximate cellular decomposition approach defined Choset. In this paper, we first propose special map coordinate assignment scheme based on active wall-finding using history sensor readings, which drastically...
Abstract Background Three dimensional (3D) cell cultures can be effectively used for drug discovery and development but there are still challenges in their general application to high-throughput screening. In this study, we developed a novel chemotherapeutic 3D screening system gastric cancer, named 'Cure-GA', discover clinically applicable anticancer drugs predict therapeutic responses. Methods Primary cancer cells were isolated from 143 fresh surgical specimens by enzymatic treatment....
Abstract This paper describes feature-based techniques for wood knot classification. For automated classification of macroscopic images, models were established using artificial neural networks with texture and local feature descriptors, the performances extraction algorithms compared. Classification trained gray-level co-occurrence matrix binary pattern, achieved better performance than those scale-invariant transform dense transform. Hence, it was confirmed that more appropriate rather an...
Techniques based on electrical resistance and near-infrared (NIR) spectroscopy were used to determine the moisture content (MC) of logging residues sweet sorghum. The MC biomass is a factor be controlled that can affect quality final products. To accurately measure in fragmented materials, it essential increase bulk density materials by compression. low increased error from oven-drying variation between repeated measurements. calculated correction made possible use commercial wood meter for...
This paper presents an on-line complete-coverage path planning algorithm for mobile robots based on approximate cellular decomposition, which abstracts the target environment using grid. Most existing grid-based coverage algorithms have a common problem of constrained mobility degrades efficiency task by inducing zigzag like path. In this paper, we propose new complete generation algorithm, linked-smooth-spiral-path (LSSP), removes constraint adopting high-resolution grid-map representation...
This paper proposes a method for cleaning robot to generate topological map from an occupancy grid-map. Virtual door is defined as the candidates of real door, and virtual doors are detected edges by extracting corner features grid-map; using this method, initial generated, which consists nodes edges. The final generated genetic algorithm merge reduce As result, divided located in doors. proposed methods provide user interaction robot, can be used plan more efficient motion including...
We propose and analyze a compact polarizing beam splitter (PBS) based on metal-insulator-metal (MIM) structure inserted into multimode interference coupler (MMI). Owing to the MIM structure, TE polarized state is reflected by cut-off condition while TM transmitted surface plasmon polariton, two states can thus be separated. In this paper, dependence of field intensities length gap thickness has been studied systematically. The proposed PBS with total size 4 × 0.7 44 µm(3) designed length,...
This paper presents a new complete coverage algorithm of robotic vacuum cleaner (RVC) with low-cost sensor in an unknown environment. To achieve coverage, the RVC must have navigation systems for precise position estimation localization and prior map or using information that has been continuously collected from do this, two-dimensional laser range finders vision sensors are becoming increasingly popular mobile robotics, various methods like these introduced by many researchers. However, it...
We propose an ultra-sensitive integrated photonic sensor structure using InP-based triangular resonator, in which a surface plasmon resonance (SPR) gold film is applied on total internal reflection mirror. have analyzed and optimized the resonator with extremely small SPR mirror sensing area of 3.3 × 0.35 μm2. Due to large phase shift mirror, significantly enhanced sensitivity 930 nm/RIU (refractive index unit) maximum peak half free spectral range been obtained at angle 24.125° Au thickness...
The aim of this study is to establish prediction models for the non-destructive evaluation carbonization characteristics lignin-derived hydrochars as a carbon material in real time. Hydrochars are produced via hydrothermal kraft lignins 1-5 h temperature range 175-250 °C, and reaction severity increases, hydrochar converted more carbon-intensive structure. Principal component analysis using near-infrared spectra suggests that spectral regions at 2132 2267 nm assigned 1449 phenolic groups...
Electrical resistance and resistivity were measured with various types of electrodes to evaluate the moisture content wood. The conventional two-pin method, electrically conductive fabrics, multi-pin used measure electrical Japanese larch (Larix kaempferi) wood, a four-pin probe was for measurements. in longitudinal direction electrode slightly affected by dimensions wood sample, whereas fabric clearly end surface area contact length between electrodes. calculated from relationship sample...
In this study CALPUFF was used to estimate the influence of temperature rise, according observation value rise based RCP scenario, on meteorological elements (wind direction, wind speed, mixing height) and change pollutant diffusion. According result. applying estimated year 2050 height is increased as per so range atmospheric diffusion widened. summer case, by 4℃ comparing with before there between 10 AM 11 PM. And wider than that rise. winter 2.3℃, has been changed 8 4 PM, showing...
A systematic investigation of mechanical testing was conducted to correlate the brittle fracture observed in Ni(P) metallization with Ni-Sn intermetallic spalling Pb-free solder joints. To produce lap shear test samples, two FR4 PCBs finished Ni(P)/Au were reflowed using Pbfree solders, Sn-3.5Ag and Sn-3.0Ag-0.5Cu (in wt.%). Brittle found joints made Sn-3.5Ag, while only ductile Cu-containing (Sn-3.0Ag-0.5Cu). For joints, (Ni,Cu)3Sn4 and/or (Cu,Ni)6Sn5 IMCs formed at interface between film....
A timber-concrete composite (TCC) slab composed of nail-laminated timber (NLT) and topping concrete (TC) was developed for flooring applications. The NLT laminated alternately with lumber plywood. To investigate the nonstructural dimensional behavior TCC slab, temperature, relative humidity (RH), changes exposed to outdoor air were monitored 205 days. Temperature change transmitted directly both components, RH gradually NLT. Concrete pouring caused a sharp increase in width, which laminating...
Electroless Ni-P has been widely used for under bump metallization (UBM) of flip chip and surface finish layer in microelectronics packaging because its excellent solderability, corrosion resistance, uniformity, selective deposition without photolithography, also good diffusion barrier. However, the brittle fracture solder joints spalling intermetallic compound (IMC) associated with electroless are critical issues successful applications. The mechanisms have extensively investigated, but not...
Metal nanoclusters were fabricated by inert-gas condensation in a sputtering reactor. From transmission electron microscopy, it was confirmed that copper with high degree of monodispersity size about 5 nm successfully produced. The conductance the percolated nanocluster film measured. In order to incorporate nano-scale arrangement characterizations nano-devices being operated air, aging experiments specimen after long time air carried. Negative temperature coefficient resistance suggests...