3,148 research outputs found
Enhanced Search Method for Ontology Classification
The web ontology language (OWL) has become a W3C recommendation to publish and share ontologies on the semantic web. In order to infer implicit information (classification, satisfiability and realization) of OWL ontology, a number of OWL reasoners have been introduced. Ontology classification is to compute a partial ordering or hierarchy of named concepts in the ontology using the subsumption testing. Most of the reasoners use both top-down and bottom-up searches using subsumption testing for ontology classification. As subsumption testing is costly, it is important to ensure that the classification process uses the smallest number of tests. In this paper, we propose an enhanced method of optimizing the ontology classification process of ontology reasoning. Our work focuses on two key aspects: The first and foremost, we describe classical methods for ontology classification. Next, we present description of the enhanced method of optimizing the ontology classification and the detailed algorithm. We evaluate the effect of the enhanced method on four different types of test ontology. The enhanced search method shows 30% performance improvement as compared with the classical method according to the result of the experiment
Observation of diurnal variations in mesoscale eddy sea-surface currents using GOCI data
The surface current field of a mesoscale eddy in the East Sea (Sea of Japan) was derived from consecutive Geostationary Ocean Color Imager chlorophyll-a (chl-a) concentration images using the normalized maximum cross-correlation method. The estimated current field of the eddy exhibited anticyclonic structure demonstrated by the objective dynamic thresholds of correlation coefficients. The eddy periphery was defined by fitting an ellipse to subjectively selected points from the frontal map of chl-a concentration data. Radial distribution and hourly variation of the current speed around the eddy were presented. In terms of the magnitude and direction, the estimated current field was in good agreement with altimeter-based current field and current vectors from surface drifters. Diurnal variations in the current speeds of the mesoscale eddies showed a quadratic relation to the wind speed
Surface currents from hourly variations of suspended particulate matter from Geostationary Ocean Color Imager data
Surface currents in Korean coastal regions were obtained using the maximum cross-correlation method applied to hourly suspended particulate matter images from the Geostationary Ocean Color Imager. Preliminary current vectors were filtered out by applying a series of quality-control procedures. The current vectors resulting from the tests were compared with the currents from a numerical model with tide and wind field. It was found that the estimated currents were more similarly to the currents caused by both tide and wind. A high degree of discrepancy was detected in regions of strong tidal currents, where the fundamental assumption of horizontal movement was limited due to the dominant vertical tidal mixing in the shallow region. The hourly rotations of the current vectors within a day were clarified by a comparison of the time-varying orientation angles of tidal ellipses. This study emphasized how to understand the short-term surface flows from hourly high-resolution geostationary satellite images
Substitution of Heavy Complementarity Determining Region 3 (CDR-H3) Residues Can Synergistically Enhance Functional Activity of Antibody and Its Binding Affinity to HER2 Antigen
To generate a biobetter that has improved therapeutic activity, we constructed scFv libraries via random mutagenesis of several residues of CDR-H3 and -L3 of hu4D5. The scFv clones were isolated from the phage display libraries by stringent panning, and their anti-proliferative activity against HER2-positive cancer cells was evaluated as a primary selection criterion. Consequently, we selected AH06 as a biobetter antibody that had a 7.2-fold increase in anti-proliferative activity (IC50: 0.81 nM) against the gastric cancer cell line NCI-N87 and a 7.4-fold increase in binding affinity (K-D : 60 pM) to HER2 compared to hu4D5. The binding energy calculation and molecular modeling suggest that the substitution of residues of CDR-H3 to W98, F100c, A101 and L102 could stabilize binding of the antibody to HER2 and there could be direct hydrophobic interactions between the aromatic ring of W98 and the aliphatic group of I613 within HER2 domain IV as well as the heavy and light chain hydrophobic interactions by residues F100c, A101 and L102 of CDR-H3. Therefore, we speculate that two such interactions were exerted by the residues W98 and F100c. A101 and L102 may have a synergistic effect on the increase in the binding affinity to HER2. AH06 specifically binds to domain IV of HER2, and it decreased the phosphorylation level of HER2 and AKT. Above all, it highly increased the overall level of p27 compared to hu4D5 in the gastric cancer cell line NCI-N82, suggesting that AH06 could potentially be a more efficient therapeutic agent than hu4D5.OAIID:RECH_ACHV_DSTSH_NO:T201620640RECH_ACHV_FG:RR00200001ADJUST_YN:EMP_ID:A002901CITE_RATE:2.67DEPT_NM:화학생물공학부EMAIL:[email protected]_YN:YCONFIRM:
P3-194: The palliative effect of endobronchial brachytherapy for previously irradiated patients
Effects of production parameters on microstructure and densification of iron/glass syntactic foam by conventional powder metallurgy
Iron and steel matrix syntactic foams have received a lot of attention owing to their high strength, temperature capability, and corrosion resistance. However, high melting point of the iron and steels complicates applications of some conventional production processes. Since few casting methods were proposed to fabricate iron and steel syntactic foams embedded with the ceramic and metal hollow spheres having macro diameters, most of the foams having micro ceramic and glass hollow spheres were fabricated through powder metallurgy (PM) process, which allows reduction of temperature levels by about 30~40% compared to the casting. Metal injection molding (MIM) was mostly used toward the iron and steel matrix foams because of requiring only limited adaptations for switching from making solid parts to syntactic foams and its capabilities for producing various geometries and sizes. However, if the shape allows the production of the part by conventional PM (pressing and sintering), MIM would in most cases be too expensive. To date, detailed fundamental researches on conventional PM process to fabricate the iron or steel syntactic foams have not been reported. Difficulties of the conventional PM process to fabricate the iron and steel syntactic foams are working pressures and temperatures. For compacting powders to make green bodies, high working pressures can assist the densification of the matrix during sintering while this can deform or fracture the hollow spheres embedded. In case of the foams with the glass hollow spheres, softening of the glass occurs at high temperature thus original shape of the hollow spheres cannot be preserved. Therefore, to overcome the difficulties and to produce sound sintered bodies, the investigation on the production parameters of the conventional PM to fabricate the iron and steel syntactic foams is necessary.
In this study, the iron/glass hollow spheres syntactic foams were fabricated via the conventional PM process. Fabrications were conducted with considering different production parameters, which included the compaction pressures and sintering temperatures in conjunction with various volume fractions and particle sizes of the hollow spheres. The microstructures and densification behaviors of the fabricated syntactic foams were characterized by X-ray diffraction, optical microscope, scanning electron microscope and energy dispersion spectroscope
Charge-spin correlation in van der Waals antiferromagenet NiPS3
Strong charge-spin coupling is found in a layered transition-metal
trichalcogenide NiPS3, a van derWaals antiferromagnet, from our study of the
electronic structure using several experimental and theoretical tools:
spectroscopic ellipsometry, x-ray absorption and photoemission spectroscopy,
and density-functional calculations. NiPS3 displays an anomalous shift in the
optical spectral weight at the magnetic ordering temperature, reflecting a
strong coupling between the electronic and magnetic structures. X-ray
absorption, photoemission and optical spectra support a self-doped ground state
in NiPS3. Our work demonstrates that layered transition-metal trichalcogenide
magnets are a useful candidate for the study of correlated-electron physics in
two-dimensional magnetic material.Comment: 6 pages, 3 figur
Efficient Unified Demosaicing for Bayer and Non-Bayer Patterned Image Sensors
As the physical size of recent CMOS image sensors (CIS) gets smaller, the
latest mobile cameras are adopting unique non-Bayer color filter array (CFA)
patterns (e.g., Quad, Nona, QxQ), which consist of homogeneous color units with
adjacent pixels. These non-Bayer sensors are superior to conventional Bayer CFA
thanks to their changeable pixel-bin sizes for different light conditions but
may introduce visual artifacts during demosaicing due to their inherent pixel
pattern structures and sensor hardware characteristics. Previous demosaicing
methods have primarily focused on Bayer CFA, necessitating distinct
reconstruction methods for non-Bayer patterned CIS with various CFA modes under
different lighting conditions. In this work, we propose an efficient unified
demosaicing method that can be applied to both conventional Bayer RAW and
various non-Bayer CFAs' RAW data in different operation modes. Our Knowledge
Learning-based demosaicing model for Adaptive Patterns, namely KLAP, utilizes
CFA-adaptive filters for only 1% key filters in the network for each CFA, but
still manages to effectively demosaic all the CFAs, yielding comparable
performance to the large-scale models. Furthermore, by employing meta-learning
during inference (KLAP-M), our model is able to eliminate unknown
sensor-generic artifacts in real RAW data, effectively bridging the gap between
synthetic images and real sensor RAW. Our KLAP and KLAP-M methods achieved
state-of-the-art demosaicing performance in both synthetic and real RAW data of
Bayer and non-Bayer CFAs
Enhanced Solubility of the Support in an FDM-Based 3D Printed Structure Using Hydrogen Peroxide under Ultrasonication
Fused deposition modeling (FDM), one of the archetypal 3D printing processes, typically requires support structures matched to printed model parts that principally have undercut or overhung features. Thus, the support removal is an essential postprocessing step after the FDM process. Here, we present an efficient and rapid method to remove the support part of an FDM-manufactured product using the phenomenon of oxidative degradation of hydrogen peroxide. This mechanism was significantly effective on polyvinyl alcohol (PVA), which has been widely used as a support material in the FDM process. Compared to water, hydrogen peroxide provided a two times faster dissolution rate of the PVA material. This could be increased another two times by applying ultrasonication to the solvent. In addition to the rapidness, we confirmed that amount of the support residues removed was enhanced, which was essentially caused by the surface roughness of the FDM-fabricated part. Furthermore, we demonstrated that there was no deterioration with respect to the mechanical properties or shape geometries of the obtained 3D printed parts. Taken together, these results are expected to help enhance the productivity of FDM by reducing the postprocessing time and to allow the removal of complicated and fine support structures, thereby improving the design capability of the FDM technique
Rapid suppression of quantum many-body magnetic exciton in doped van der Waals antiferromagnet (Ni,Cd)PS3
The unique discovery of magnetic exciton in van der Waals antiferromagnet
NiPS3 arises between two quantum many-body states of a Zhang-Rice singlet
excited state and a Zhang-Rice triplet ground state. Simultaneously, the
spectral width of photoluminescence originating from this exciton is
exceedingly narrow as 0.4 meV. These extraordinary properties, including the
extreme coherence of the magnetic exciton in NiPS3, beg many questions. We
studied doping effects using Ni1-xCdxPS3 using two experimental techniques and
theoretical studies. Our experimental results show that the magnetic exciton is
drastically suppressed upon a few % Cd doping. All these happen while the width
of the exciton only gradually increases, and the antiferromagnetic ground state
is robust. These results highlight the lattice uniformity's hidden importance
as a prerequisite for coherent magnetic exciton. Finally, an exciting scenario
emerges: the broken charge transfer forbids the otherwise uniform formation of
the coherent magnetic exciton in (Ni,Cd)PS3.Comment: 40 pages, 4 main figures, 13 supporting figures, accepted by Nano
Letter
- …