• The Journal of the Convergence on Culture Technology
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• v.7 no.4
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• pp.675-681
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• 2021

With the recent growth of the AI speaker market, the demand for speech synthesis technology that enables natural conversation with users is increasing. Therefore, there is a need for a multi-speaker speech synthesis system that can generate voices of various tones. In order to synthesize natural speech, it is required to train with a large-capacity. high-quality speech DB. However, it is very difficult in terms of recording time and cost to collect a high-quality, large-capacity speech database uttered by many speakers. Therefore, it is necessary to train the speech synthesis system using the speech DB of a very large number of speakers with a small amount of training data for each speaker, and a technique for naturally expressing the tone and rhyme of multiple speakers is required. In this paper, we propose a technology for constructing a speaker encoder by applying the deep learning-based x-vector technique used in speaker recognition technology, and synthesizing a new speaker's tone with a small amount of data through the speaker encoder. In the multi-speaker speech synthesis system, the module for synthesizing mel-spectrogram from input text is composed of Tacotron2, and the vocoder generating synthesized speech consists of WaveNet with mixture of logistic distributions applied. The x-vector extracted from the trained speaker embedding neural networks is added to Tacotron2 as an input to express the desired speaker's tone.

• Journal of the Korean earth science society
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• v.29 no.2
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• pp.189-203
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• 2008

Microcomputer Based Laboratory (MBL), by offering accurate and effective data collection and real-time graphs, enables students to reduce experiment time and, thereby, have deeper discussions concerning experimental results. This helps to emphasis the essential aspect of scientific inquiry; the process communication. Therefore, this study examined secondary school earth science MBL lessons with regards to the five basic aspects of scientific inquiry: "Asking", "Evidencing", "Explaining", "Evaluating" and "Communicating". It then investigated the level of argumentative communication between the students and teachers and also among the students themselves. For this study, three classroom activities were observed and videotaped, and teaching materials, textbooks and students' notes were collected. The transcribed data were analyzed from the perspective of scientific inquiry level and argument frames. The results showed that the scientific inquiry levels of the three classes were similar, except for the "Communicating" aspect, which appeared in only one episode. "Asking" was carried out by the teacher and then students were directed to collect certain data in the "Evidencing" stage. Furthermore, students were given possible ways to use evidence to formulate explanations and connections through the "Explaining" and "Evaluating" stages. In the argumentation analysis, most argumentative communication was identified as being associated with a given procedure, rather than with any scientific phenomena. In only one episode, did "Communicating" relate directly to any scientific phenomena. It can be concluded, that although MEL places emphasis on communication for authentic scientific inquiry, the environment required for such inquiry and argumentative communication can not be easily created in the classroom. Therefore, in order for authentic inquiry to take place in the MBL classroom, teachers should provide students with the opportunity to develop meaningful argumentation and scaffolding abilities.

• Journal of Life Science
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• v.24 no.5
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• pp.467-475
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• 2014

Sea buckthorn (Hippophae rhamnoides L.) is a well-known and rich source of biologically active compounds, such as flavonoids, carotenoids, steroids, vitamins, tannins, and oleic acid. The effects of sea buckthorn fruit extract (SBFE) on ultraviolet (UV)-induced cell death was investigated in SK-MEL-2 cells cotreated with UV and a low concentration (LoC), medium concentration (MeC), or high concentration (HiC) of SBFE. Cell viability gradually decreased in accordance with an increase in the UV dose. The cell viability of the UV+SBFE cotreated cells increased significantly compared to that of UV+vehicle-treated cells during the application of an appropriate UV radiation dose (400 mJ). In addition, the number of 4',6-diamidino-2-phenylindole (DAPI), propidium iodine (PI)-, and annexin V-stained apoptotic cells was higher in the UV+vehicle-treated cells than in the UV untreated cells. The decrease of apoptotic cell numbers varied in each treated group, but it was most significant in the SBFE-treated group. The number of PI-stained cells dramatically decreased in accordance with the concentration of SBFE, and the maximum decrease was detected in the UV+HiC-treated group. In addition, Bax expression increased and Bcl-2 expression decreased in the SBFE-treated group compared with the UV-only treated group. The level of caspase-3 remained constant in all the groups. These results suggest that SBFE may contribute to a recovery from UV-induced cell death through the regulation of apoptotic protein expression and that it may have potential therapeutic utility in ameliorating UV-induced skin ageing.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.31 no.4 s.54
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• pp.349-357
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• 2005

New antioxidative substances for cosmeceuticals were screened from natural resources such as microbial metabolites, mushrooms, and medicinal plants. Four antioxidants were isolated from the fungal metabolite of Eupenicillium shearii and their structures were determined to be new phenolic compounds. The compounds were designated as melanocins A, B, C, and D. Melanocins $A{\sim}D$ exhibited free radical scavenging activity on DPPH and superoxide with $EC_{50}$ values of $21{\sim}94\;and\;7{\sim}84{\mu}M$, respectively, which were stronger activity than those of ${\alpha}-tocopherol$ and BHA. Melanocin A showed anti-wrinkle effects on the UV-irrated hairless mouse skin. A novel hispidin antioxidative compound designated as inoscavin A was isolated from the fruiting body of the mushroom, Inonotus xeranticus. Inoscavin A scavenged superoxide radical with $EC_{50}$ values of $0.03{\mu}g/mL$, and inhibited rat liver microsomal lipid peroxidation with $EC_{50}$ values of $0.3{\mu}g/mL$. Benzastatins $A{\sim}G$, the novel antioxidants isolated from the culture of Streptomyces nitrosporeus showed potent lipid peroxidation inhibitory activity with $EC_{50}$ values of $3{\sim}30{\mu}M$. A cyclopentene compound with strong hypopigmentary effect was isolated from the fungal metabolite of Penicillium sp. and identifed as terrein. Terrein significantly reduced melanin levels in a melanomacyte cell line, Mel-Ab. It showed 10 times stronger activity than kojic acid, but exhibited no cytotoxic effect even in $100{\mu}M$. It was suggested that terrein reduced melanin synthesis by reducing tyrosinase production by MITF down-regulation.

• Korean Journal of Breeding Science
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• v.42 no.4
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• pp.397-406
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• 2010

Field screening method has been commonly used for purity test of $F_1$ hybrid seeds in melon and oriental melon. However, as this method takes a lot of time and cost, molecular marker-based purity test is necessary. To develop molecular markers for purity test, thirty pairs of SNP (single nucleotide polymorphism) primers were obtained from melon EST sequences, and 10 polymorphic markers showing HRM (high resolution melting) polymorphisms between parents of two melon cultivars and one oriental melon cultivar were selected. Blind tests were performed to validate usefulness of the selected markers for purity test. Blind test results showed that HRM genotypes were matched with the expected identity of individual sample, $F_1$ hybrid, male or female parents. Three HRM-based SNP markers were converted to CAPS markers for general use which is favor to breeders. We expect that SNP markers developed in this study will be useful for purity test of $F_1$ hybrid seeds in melon and oriental melon.