• Journal of Korean language education
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• v.28 no.4
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• pp.1-38
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• 2017

This longitudinal study analyzed syntactic development (Complexity, Accuracy, and Fluency; CAF) of six L2 Korean learners in a natural learning context. The learners recalled the stories of a short animated video through speaking and writing every 3 months, from month 0 to 15. The learners' responses were analyzed for a series of CAF measures and their cognitive, psychological, and social variables were investigated. The results showed that (i) L2 Korean learners' speaking and writing in various time periods showed significant differences in spoken and written accuracy, and complexity; (ii) the correlation between spoken and written complexity, spoken and written accuracy, as well as spoken and written fluency were significant, and (iii) the regression analysis showed that learners' cognitive, social, and psychological variables have significant effect on the L2 Korean syntactic development. The current study reports that L2 Korean learners engaged in self-learning in a natural learning environment without formal instruction made significant syntactic development.

• Composites Research
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• v.36 no.6
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• pp.383-387
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• 2023

Carbon fiber-reinforced composites have excellent mechanical properties. However, the fracture toughness is a disadvantage due to brittle failure mode. The fracture toughness can be enhanced using hybridization with large-elongation fibers. In this study, polyamide (aramid) fibers are hybridized with carbon fiber with various stacking sequences. As a result, the Izod impact strength was enhanced by 63% with 25% aramid fiber hybridization. It is also shown that there is an optimal point in laminated composite hybridization, [CF/CAF₂/CF]_s stacking sequence.

• Journal of the East Asian Society of Dietary Life
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• v.17 no.3
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• pp.409-416
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• 2007

This study investigated changes in the catechin and alkaloid contents of Bosung green tea during different manufacturing processes and storage periods, using HPLC and UV-VIS spectrophotometer analysis. For changes in the catechin and alkaloid contents by roasting technique, we found that EGCG, CG and GCG decreased just slightly by processes performed before roasting, rather than after roasting. In addition, theobromine, caffeine, and ECG changed minimally throughout all the processes. For changes in the catechin and purine alkaloid contents of the green tea leaves during storage, EGCG, ECG, and CAF decreased considerably in the green tea stored at temperatures of $5^{\circ}C$ and $25^{\circ}C$, and they decreased by $20{\sim}30%$ after storage for 1 year. However, a quantitative difference was hardly observed in the catechin and alkaloid contents regardless of storage temperature.

• Journal of the Korean Society of Safety
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• v.13 no.3
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• pp.126-134
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• 1998

In this paper, the field test by truck load and the structural analysis were performed on a prestressed concrete beam bridge to investigate the load carrying capacity of the prestressed concrete beam bridges. From the results of the field test and the structural analysis, CAF (composite action factor), TIF(transformed impact factor), and $P_n$(load carrying capacity) of the prestressed concrete beam bridges were studied, and the load carrying capacity assessment of the prestressed concrete beam bridges were carried out using these factors.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.05a
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• pp.718-721
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• 2011

In this paper, cross ambiguity function map is proposed to estimate the location of a unknown interferer which emits the harmful radio in the satellite communication network. To estimate the interferer, a time difference between received radio signals at earth stations and a frequency difference caused by the movement of interferers or receiving earth stations are calculated. Therefore, cross ambiguity function is used to calculate that values. The calculating process of the time and the frequency differences using cross ambiguity function is operated at every designated time then the correlation values between the time and frequency are calculated. After calcuation, the final location of the harmful interferer is estimated. From the simulation results, about 800 m distance error is occurred at 10~4 dB of $E_b/N_0$ and about 13 km distance errer is occurred at -20 dB of $E_b/N_0$.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.11
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• pp.6845-6850
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• 2013

Background: This study was performed to gather data on second-hand smoke (SHS) concentrations in a range of public venues following the implementation of partial Smoke-Free Legislation in Malaysia in 2004. Materials and Methods: $PM_{2.5}$ was measured as a marker of SHS levels in a total of 61 restaurants, entertainment centres, internet caf$\acute{e}$s and pubs in Kuala Lumpur, Malaysia. Results: Under the current smoke-free laws smoking was prohibited in 42 of the 61 premises. Active smoking was observed in nearly one-third (n=12) of these. For premises where smoking was prohibited and no active smoking observed, the mean (standard deviation) indoor $PM_{2.5}$ concentration was 33.4 (23.8) ${\mu}g/m^3$ compared to 187.1 (135.1) ${\mu}g/m^3$ in premises where smoking was observed The highest mean $PM_{2.5}$ was observed in pubs [361.5 (199.3) ${\mu}g/m^3$]. Conclusions: This study provides evidence of high levels of SHS across a range of hospitality venues, including about one-third of those where smoking is prohibited, despite 8 years of smoke-free legislation. Compliance with the legislation appeared to be particularly poor in entertainment centres and internet caf$\acute{e}$s. Workers and non-smoking patrons continue to be exposed to high concentrations of SHS within the hospitality industry in Malaysia and there is an urgent need for increased enforcement of existing legislation and consideration of more comprehensive laws to protect health.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.5
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• pp.600-605
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• 2018

The Indo-Pacific bottlenose dolphins Tursiops aduncus are the only cetacean species that can be observed visually on coastal areas of Jeju Island and regarded as one of valuable tour resources. We attempted to figure out location and timing information of the dolphin sightings collected from two major social media, Naver $Caf{\acute{e}}$ and Instagram. 142 of dolphin sighting information were derived from 2,501 dolphin related postings on Naver $Caf{\acute{e}}$ between 2004 to 2017. 292 informative postings also were found on Instagram through hashtag searching. The number of posts about dolphin sighting was not frequent until 2014. Since 13 posts were found in 2014, dramatic increase of the sighting numbers was accelerated as 38 in 2015, 93 in 2016 and 269 in 2017. 195 (45.7%) from coastal area of Daejeong-eup, south-western part of the Island, were posted. The number of dolphin sightings also high from Gujwa-eup(n=50, 11.7%), Hangyeong-myeon (n=49, 11.5%), Seongsan-eup (n=38, 8.9%) and Seogwipo-si (n=34, 8.0%). Our results show that social media data has a high potential to be used as a data source for study of distribution pattern of the dolphins.

• Culinary science and hospitality research
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• v.22 no.5
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• pp.267-276
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• 2016

This study used HPLC to analyze the contents of catechins, alkaloids, and theanine of commercial green tea. Green tea samples were stored for 6 months at five different temperatures, $30^{\circ}C$, $15^{\circ}C$, $4^{\circ}C$, $-15^{\circ}C$ and $-40^{\circ}C$. Catechins change in storage temperature was $30^{\circ}C$ > $15^{\circ}C$ > $4^{\circ}C$ > $-15^{\circ}C$ > $-40^{\circ}C$ stored for 6 months. Total alkaloids content higher levels were CAF(27.49 mg/g) with lower level of TB(2.16 mg/g) and TP(0.28 mg/g). The total alkaloids content decreased in the longer storage periods, a similar case with, although CAF were almost unchanged in all storage temperatures. The results indicate that temperature and storage time are important in the storage of green tea, with refrigerated and frozen conditions as preferable to increase or preserve the chemical compounds of the green tea.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.13 no.2
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• pp.120-125
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• 2013

Purpose: McCune-Albright syndrome (MAS) is caused by activating mutations in the GNAS gene, resulting in peripheral precocious puberty, caf$\acute{e}$-au-lait spots, and polyostotic fibrous dysplasia (POFD). The aim of the present study was to describe the diverse clinical and endocrine characteristics of patients with MAS. Methods: Seven patients with MAS were included in this study and medical charts were reviewed retrospectively for following parameters: patient's sex and age at diagnosis, POFD, ovarian cysts, and precocious puberty. Results: The mean age at diagnosis was $5.8{\pm}4.2$ years. One patient was male (14%) and the other six patients were female (86%). Peripheral precocious puberty was associated with 6 patients (86%). Five patients manifested premature menarche as early as 2 to 5 years of age. Letrozole was administered to 4 patients, tamoxifen to one patient and GnRH agonist to one patient. Five females developed ovarian cysts. Thyroid function tests were performed in all patients and one patient showed hyperthyroidism (14%) and has been treated with methimazole. One patient presented with pseudohypoparathyroisdism, phosphaturia, calciuria suggesting hypophosphatemic rickets. Six patients (86%) revealed POFD. One patient had symptoms of optic nerve compression and secondary esotropia and 2 patients had bone pain. Conclusion: This study described clinical characteristics and endocrine complications of patients with MAS. Careful physical examinations with history taking and serial endocrine function tests should be needed to detect complications such as endocrinologic hyperfunction and POFD.

• Journal of Microbiology and Biotechnology
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• v.29 no.8
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• pp.1288-1298
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• 2019

Bacterial ATP synthases drive ATP synthesis by a rotary mechanism, and play a vital role in physiology and cell metabolism. Corynebacterium glutamicum is well known as an industrial workhorse for amino acid production, and its ATP synthase operon contains eight structural genes and two adjacent genes, cg1360 and cg1361. So far, the physiological functions of Cg1360 (GenBank CAF19908) and Cg1361 (GenBank CAF19909) remain unclear. Here, we showed that Cg1360 was a hydrophobic protein with four transmembrane helices (TMHs), while no TMH was found in Cg1361. Deletion of cg1360, but not cg1361, led to significantly reduced cell growth using glucose and acetic acid as carbon sources, reduced F1 portions in the membrane, reduced ATP-driven proton-pumping activity and ATPase activity, suggesting that Cg1360 plays an important role in ATP synthase function. The intracellular ATP concentration in the ${\Delta}cg1360$ mutant was decreased to 72% of the wild type, while the NADH and NADPH levels in the ${\Delta}cg1360$ mutant were increased by 29% and 26%, respectively. However, the ${\Delta}cg1361$ mutant exhibited comparable intracellular ATP, NADH and NADPH levels with the wild-type strain. Moreover, the effect of cg1360 deletion on L-valine production was examined in the L-valine-producing V-10 strain. The final production of L-valine in the $V-10-{\Delta}cg1360$ mutant reached $9.2{\pm}0.3g/l$ in shake flasks, which was 14% higher than that of the V-10 strain. Thus, Cg1360 can be used as an effective engineering target by altering energy metabolism for the enhancement of amino acid production in C. glutamicum.