• Proceedings of the KSME Conference
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• 2002.08a
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• pp.283-286
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• 2002

The mixing of fuel and oxidizer and each mass distribution of unlike split triplet(F-O-O-F) injector for liquid rocket which are known to affect the combustion efficiency significantly, has been investigated using PLLIF technique. Experiment is conducted to investigate the effect of mixture ratio(MiR), momentum ratio(MoR) and impinging angle on mixing efficiency. The mixing efficiency, which is introduced by Rupe, gives the global chracteristic of spray mixing. Experiment far comparison with triplet injector(F-O-F), which has same momentum ratio and impinging angle with split triplet injector is conducted.

• Journal of Photoscience
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• v.5 no.3
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• pp.125-129
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• 1998

Occurrence of an electron (or H atom equivalent to one electron plus H+) transfer from $\alpha$- tocopherol $\alpha$(TOH) to a number of photosensitizers in theri triplet states were investigated by monitoring the ESR signal of $\alpha$-chromaoxyl radical ($\alpha$(TO.) in ethanolic solutions of $\alpha$TOH and the sensitizers under continuous illumination. Every sensitizer molecule examined, such as protocholorophyllide (Pchl), hematoporphyrin and rose bengal which are generally regarded as efficient type II photosensitizers and thus have long-lived triplet states, was found to actively participate in an electro transfer reaction with $\alpha$TOH even under air-saturation conditions, generating $\alpha$TOH complex as an intermediate in a fashion of Michaelis-Menten type of reaction. For the reaction of $\alpha$TOH with triplet Pchl, the rate law was derived by applying the steady approximation for the binary complex, triplet Pchl-$\alpha$TOH , which turned out to be well consistent with the kinetic data.

• Bulletin of the Korean Chemical Society
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• v.22 no.6
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• pp.605-610
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• 2001

The molecular geometries and harmonic vibrational frequencies of dibenzofuran in the ground and lowest triplet state have been calculated using the Hartree-Fock and Becke-3-Lee-Yang-Parr(B3LYP)density functional methods with the 6-31G basis set. Upon the excitation to the lowest triplet state, the molecular structure retains the planar form but distorts from a benzene-like to a quinone-like form in skeleton. Scaled vibrational frequencies for the ground and lowest triplet state obtained from the B3LYP calculation show excellent agreement with the available experimental data. A few vibrational fundamentals for both states are newly assigned based on the B3LYP results.

• Perinatology
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• v.29 no.4
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• pp.180-184
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• 2018

In assisted reproductive techniques, monozygotic twinning is not influenced by the trial of reducing the number of embryos transferred. We present extremely rare case of monochorionic triamniotic triplet pregnancy following in vitro fertilization and two-embryo transfer. During the first trimester, the crucial ultrasound findings of monochorionic triamniotic triplet pregnancy are three distinct amniotic sacs forming a triangle or ipsilon zone within a single chorionic cavity. After prudential counseling about the potential risk of a monochorionic triamniotic triplet pregnancy with the patient, selective reduction of two fetuses via radiofrequency ablation was performed. We report a case of selective reduction for monochorionic triamniotic triplet pregnancy using radiofrequency ablation at 12 weeks' gestation and obstetric progression after radiofrequency ablation was uneventful until 20 weeks' gestation.

• Bulletin of the Korean Chemical Society
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• v.22 no.1
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• pp.63-67
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• 2001

The photophysical properties and the singlet oxygen generation efficiency of tetrathiarubyrin have been investigated to elucidate the possibility of its use as a photodynamic therapy (PDT) photosensitizer by steady-state and time-resolved spectroscopic methods. The observed photophysical properties were affected by various molecular aspects, such as extended ${\pi}conjugation$, structural distortion, and internal heavy atom. The steady-state electronic absorption spectrum was red-shifted due to the extended $\pi-conjugation$, and the spin orbital coupling was enhanced by the structural distortion and the internal heavy atom effect. As a result of the enhanced spin orbital coupling, the triplet quantum yield increased to 0.90 $\pm$ 0.10 and the triplet state lifetime was shortened to 7.0 $\pm$ 1.2 ${\mu}s$. Since the triplet state decays at a relatively faster rate, the efficiency of the oxygen quenching of the triplet state decreases. The singlet oxygen quantum yield was estimated to be 0.52 $\pm$ 0.02, which is somewhat lower than expected. On the other hand, the efficiency of singlet oxygen generation during the oxygen quenching of triplet state, $f{\Delta}^T$, is near unity. Such high efficiency of singlet oxygen generation can be explained by the following two possible factors: The hydrogen bonding of ethanol which impedes the deactivation pathway of the charge transfer complex with oxygen to the ground state, the less probability of the aggregation formation.

• Earthquakes and Structures
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• v.25 no.3
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• pp.149-160
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• 2023

Over the course of the last 4-5 years, India's northeastern region have widely used Autoclaved Aerated Concrete (AAC) blocks to construct load-bearing masonry structures. The aim of this investigation is to examine the shear characteristics of AAC masonry triplet assemblage strengthened by using two techniques, i.e., the bead joint (BJ) and the bed-head joint (BHJ) technique. Three unique variations of wire mesh were involved in the strengthening method. Furthermore, three strengthening configurations were used to strengthen each of the three wire mesh variations and the two-strengthening method, i.e. (-), L and (Z) configuration. The unreinforced and reinforced triplet masonry wallets were tested under direct shear test. From the results obtained, the 'BJ'triplet masonry wallets observed an enhanced in shear strength of about 2.23% to 23.33 % whereas the 'BHJ' triplet masonry wallets observed an enhanced in shear strength of about 22.92% to 50.69%. The "BHJ" strengthening method effectively enhance the shear strength of the triplet masonry wallets compared to the "BJ" and the "UR" wallets with an increase in capacity as the wire mesh strength increases. Furthermore, in terms of the strengthening configuration, the (Z) configuration performs better, followed by the (L) and (-) configuration demonstrating the strengthening configuration effectiveness.

• Bulletin of the Korean Chemical Society
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• v.23 no.2
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• pp.281-285
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• 2002

The photophysical properties and the singlet oxygen generation efficiencies of meso-tetraphenyl-trithiasapphyrin $(S_3TPS)$ and meso-tetmkis(p-methoxy phenyl)-trithiasapphy rin ((p-MeO)-$S_3TPS$) have been investigated, utilizing steady-state and time-resolved spectroscopic methods to elucidate the possibility of their use as photosensitizers for photodynamic therapy (PDT). The observed photophysical properties were compared with those of other porphyrin-like photosensitizers in geometrical and electronic structural aspects, such as extended ${\pi}$ conjugation, structural distortion, and internal heavy atoms. The steady-state electronic absorption and fluorescence spectra were both red-shifted due to the extended ${\pi}$-conjugation. The fluorescence quantum yields were measured as very small. Even though intersystem crossing rates were expected to increase due to the increment of spin orbital coupling, the triplet quantum yields were measured as less than 0.15. Such characteristics can be ascribed to the more enhanced internal conversion rates compared with the intersystem crossing rates. Furthermore, the triplet state lifetimes were shortened to -1.0 ${\mu}s$ as expected. Therefore, the singlet oxygen quantum yields were estimated to be near zero due to the fast triplet state decay rates and the inefficient energy transfer to the oxygen molecule as well as the low triplet quantum yields. The low efficiencies of energy transfer to the oxygen molecule can be attributed to the lower oxidation potential and/or the energetically low lying triplet state. Such photophysical factors should be carefully evaluated as potential photosensitizers that have extended ${\pi}$-conjugation and heavy core atoms synthesized for red-shifted absorption and high triplet state quantum yields.

• Journal of Korea Society of Industrial Information Systems
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• v.27 no.1
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• pp.1-9
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• 2022

The goal of this paper is to create a deep learning model based on triplet loss for generating similar child drawing selection algorithms. To assess the similarity of children's drawings, the distance between feature vectors belonging to the same class should be close, and the distance between feature vectors belonging to different classes should be greater. Therefore, a similar child drawing selection algorithm was developed in this study by building a deep learning model combining Triplet Loss and residual network(ResNet), which has an advantage in measuring image similarity regardless of the number of classes. Finally, using this model's similar child drawing selection algorithm, the similarity between the target child drawing and the other drawings can be measured and drawings with a high similarity can be chosen.

• Proceedings of the Korean Society of Potoscience Conference
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• spring
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• pp.11-12
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• 1999

• The Journal of the Acoustical Society of Korea
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• v.36 no.2
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• pp.115-122
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• 2017

We propose a robust adaptive beamforming algorithm for triplet array sonar. The proposed beamforming algorithm obtains robustness to mismatches, left/right discrimination, and has two steps. The first is a cardioid beamformer, which supports left/right discrimination of target signals. It applies the conventional delay-and-subtract to each triplet's signal with its rotation angle and obtains multiple cardioid beams. The second is a robust adaptive beamforming to minimize nearby interferences. We regard cardioid beams as input signals of a line array and apply an adaptive beamforming algorithm to the cardioid beams. Simulations results show that the proposed algorithm provides significantly better performance than the conventional algorithms, while supporting left/right discrimination of target signals.