• Phonetics and Speech Sciences
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• v.12 no.1
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• pp.11-17
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• 2020

Non-tonal language speakers may have difficulty learning second language lexical tones. In the present study, we explored this issue with Korean-speaking learners of Mandarin Chinese (i.e., non-tonal first language speakers) by examining their perception and production of Mandarin lexical tones. In the perception experiment, the Korean learners were asked to listen to the tone of each stimulus and assign it to one of four Mandarin lexical tones using the response keys; in the production experiment, the learners provided speech production data for the lexical tones and then their productions were identified by native listeners of Mandarin Chinese. Our results showed that the Korean learners of Mandarin Chinese had difficulty in perceptually distinguishing Tone 2 and Tone 3, with the most frequent production error being the mispronunciation of Tone 3 as Tone 2. We also investigated whether unfamiliar non-native phonemes (i.e., Chinese phonemes) that do not exist in the native language phonemic inventory (i.e., Korean) may hinder the processing of the non-native lexical tones. We found no evidence for such effects, neither for the perception nor for the production of the tones.

• Korean Journal of Organic Agriculture
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• v.16 no.2
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• pp.189-204
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• 2008

The objective of this paper is to analyze consumers' consumption behavior of environment-friendly mandarin and attributes of mandarin in Korea. It is also to measure consumers' marginal willingness to pay by the attributes of mandarin and to estimate the market-share by products of mandarin from the data surveyed by a survey research company. The questionnaires for consumers were given randomly by interview to 500 married women lived in Seoul and to 200 wholesaler in Seoul, Busan, Daegu, Kwangju. The conjoint analysis method was used to analyze consumers' preference and suggest several implications for the rational production and marketing policy of mandarin.

• Journal of Agricultural Extension & Community Development
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• v.28 no.3
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• pp.153-165
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• 2021

This study aims to analyze the difference in production elasticity based on the types of agricultural labor input regarding its qualitative difference in Jeju mandarin production. To estimate the production function of qualityadjusted labor, we have set up a Quality-Adjusted Index based on the market wage of the agricultural field. We have conducted a multiple regression analysis of the newly estimated labor inputs using the Ordinary Least Squares regression. Results show that the production efficiency of aggregate total labor hours (quality-unadjusted labor input) is overestimated compared to quality-adjusted labor with qualitative labor homogeneity. Moreover, by analyzing household labor and employment labor, we have observed that the marginal productivity of household labor exceeds that of employment labor. In conclusion, this study verifies that securing labor input homogeneity is crucial for analyzing agricultural labor hours' economic efficiency accurately.

• Korean Journal of Environmental Agriculture
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• v.37 no.3
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• pp.207-212
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• 2018

BACKGROUND: Recently, the need for a method to cultivate 'Haryejosaeng' Satsuma mandarin has been increasing. However, there is limited information available as this is a new Satsuma mandarin cultivar, which was bred by the RDA in 2004. Many farmers who cultivate this cultivar follow the cultivation method similar to that used for 'Miyagawa' Satsuma mandarin, and suffer low production of optimum-sized fruits. METHODS AND RESULTS: This study was conducted to find out the optimum ratio of leaf-to-fruit for the stable production of high quality 'Haryejosaeng' Satsuma mandarin fruits in a non-heated plastic film house. Seven-year-old 'Haryejosaeng' Satsuma mandarin trees were used in the study. Before the treatment, the leaf-to-fruit ratio ranged from 5.7 to 17.9. The treatments included 10, 20, 30, and 40 leaves per fruit. The fruits were removed if over fruiting was observed at day 60 after full bloom. We investigated the fruit size and quality on the day of harvest. Flowering and fruiting patterns in each treatment were recorded for the following year. In the experiments, the flower-to-leaf ratio was 1.12 to 1.74. As the leaf-to-fruit ratio decreased, the fruit size and weight also decreased. Contrarily, the higher the ratio of leaf-to-fruit, the higher fruit size and weight were. It was noted that the ratio of 20:1 was ideal to produce the M grade optimum-sized Satsuma mandarin fruits on the day of harvest. However, higher ratio might result in fruits weighting above 100 g. There was no difference among the treatments in terms of fruit quality, such as total soluble solid contents, titratable acid, and color. In the subsequent years, flowering and fruiting in the treatments were lowered when the leaf number per fruit was 10, but they were improved when the leaf number per fruit was above 20. CONCLUSION: Based on the above results, the optimum ratio of leaf-to-fruit was found to be 20:1 for flowering and fruiting of 'Haryejosaeng' Satsuma mandarin. It is important that optimum ratio of leaf-to-fruit is set as a standard to produce good grade and quality of 'Haryejosaeng' Satsuma mandarin fruits.

• YAKHAK HOEJI
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• v.47 no.1
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• pp.25-30
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• 2003

This study is performed to investigate the effects of citrus essential oils on melanin production in B16 melanoma cells. Five kinds of citrus essential oils (Bergamot, Grapefruit, Lemon, Mandarin, Petigrain) did not have any influence on DPPH radical scavenger activity, cell growth and cytotoxicity in B16 melanoma cells. Both mandarin and petigrain essential oils dose-dependently inhibited purified tyrosinase activity, but bergamot did not. In 1$\mu$M MSH-stimulated B16 melanoma cells, all of 5 citrus essential oils inhibited melanin production in a dose dependent manner. From the above results, it is possible that citrus essential oils may be developed to be an anti-melanogenesis agent on the basis of their inhibitory effect on MSH-induced melanin production.

• International Journal of Industrial Entomology and Biomaterials
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• v.46 no.2
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• pp.34-40
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• 2023

As agricultural production increases due to population growth, agricultural by-products that are generated at all production stages increase commensurately. Black soldier fly (BSF) (Hermetia illucens) treatment has potential as an environmentally friendly process to combat the environmental pollution caused by agricultural by-products. This study examined the utilization of BSF larvae in the decomposition of the by-products of apples and mandarins, fruits commonly produced in South Korea. The BSF test larvae were fed apple pomace or mandarin waste, and the control larvae were fed calf feed. Larval weight and size were measured at 4-day intervals until larvae reached the pre-pupal stage. Larval development time, survival rate, and BSF fecundity rate were calculated for all three substrates. Waste reduction and bioconversion ratios were also calculated. The developmental time of larvae fed with apple pomace and mandarin waste was greater than that of the control larvae. The average weight of larvae fed with the fruit by-products was less than that of the control. There was no significant difference in the survival rate of BSF larvae or the fecundity rate of BSF between the substrates used in this study. BSF larvae decomposed 48.0% and 61.5% of apple pomace and mandarin waste, respectively. The bioconversion efficiency rates of BSF larvae fed with apple pomace and mandarin waste were 9.1% and 12.1%, respectively. These results indicated that decomposition of single fruit by-products by BSF larvae is an environmentally friendly and effective bioconversion process.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.31 no.3 s.52
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• pp.265-271
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• 2005

This study is performed to investigate the effects of citrus essential oils on melanin production in B16 melanoma cells and reactive oxygen species (ROS) generation in RBL 2H3 cells. Five kinds of citrus essential oil (bergamot, grapefruit, lemmon, mandarin, petigrain) did not have any influence on DPPH radical scavenger activity, cell growth and cytotoxicity in B16 melanoma cells. In purified tyrosinase assay, both mandarin and petigrain essential oils dose-dependently inhibited its activity, but bergamot did not. In $1{\mu}M\;{\alpha}-MSH-stimulated$ B16 melanoma cells, all of 5 citrus essential oils inhibited melanin production in $\underline{a}$ dose dependent manner. On the other hand, four kinds of citrus essential oil dose-dependently increased ROS generation in RBL 2H3 mast cells, but mandarin did not. From the above results, it is possible that citrus essential oils nay be developed to be anti-melanogenic agent on the basis of their inhibitory effect on MSH-induced melanin production. Hut we can not rule out the possibility of the induction of allergy and inflammation since citrus essential oils caused ROS generation in RBL 2H3 mast cells.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 1997.06a
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• pp.291-292
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• 1997

• Phonetics and Speech Sciences
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• v.12 no.1
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• pp.1-9
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• 2020

The perceptual assimilation of a nonnative phonological contrast can change with linguistic experience, resulting in naïve listeners and novice second language (L2) learners potentially assimilating the members of a nonnative contrast to different native (L1) categories. While it has been shown that this sort of change can affect the discrimination of the nonnative contrast, it has not been tested whether such a change could have consequences for the production of the contrast. In this study, L1 speakers of Mandarin Chinese who were (1) naïve to Korean, (2) novice L2 learners, or (3) advanced L2 learners participated in a Korean non-word repetition task using word-initial sibilants. The initial CVs of their repetitions were then played to L1 Korean listeners who categorized the initial consonant. The naïve talkers were more likely to repeat an initial /s^ha/ as an affricate, whereas the L2 learners repeated it as a fricative, in line with how these listeners have been shown to assimilate Korean sibilants to Mandarin categories. This result suggests that errors in the production of new words presented auditorily to nonnative listeners may be driven by how they perceptually assimilate the nonnative sounds, emphasizing the need to better understand what drives changes in perceptual assimilation that accompany increased linguistic experience.

• Food Science and Preservation
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• v.6 no.1
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• pp.7-10
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• 1999

Physicochemical properties of Satsuma mandarin(Citrus unshiu Marc. var. miyagawa) harvested in middle of November according to production areas of Cheju were investigated. Peel thickness of citrus fruits was ranged from 2.54mm to 3.13mm, and it was lower on fruits harvested in western areas than those of other areas in Cheju. Soluble solids were ranged from 10.1 to 12.0$^{\circ}$Brix, and it was lower on fruits harvested in southern areas. Acid contents of citrus juice were ranged from 1.28% to 1.42%, it was higher on fruits harvested in eastern areas, specific gravity of citrus fruits was ranged between 0.86 and 0.88. Flesh ratio was ranged from 75.1% to 77.6%, it was lower on fruits harvested in southern areas. Soluble solids, acid content and specific gravity harvested in southern areas of below 100m and over 150m sea level altitude were 11.8 and 11.2, 1.43% and 1.40%, 0.87 and 0.9, respectively. Fruits quality harvested in southern areas was better, compared to other harvest areas of Cheju.