• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.3
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• pp.266-270
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• 1999

Two forms of gonadotropin releasing hormone (GnRH) are identified in the brain of adult mature spotted sea bass (Lateolabrax sp.) by immunohistochemical methods. Salmon GnRH immunoreactive (sGnRH-ir) cell bodies were distributed in the olfactory bulb, ventral telencephalon and preoptic region. Immunoreactive fibers were observed in the vicinity of the brain including the olfactory bulbs, the telencephalon, the optic nerve, the optic tectum, the cerebellum, the medulla oblongata and rostral spinal cord. In most cases, these fibers did not form well defined bundles. However, there was a clear continuum of immunoreactive fibers, extending from the olfactory bulbs to the pituitary. cGnRH-II-ir cell bodies were only found in olfactory bulbs. However, the distribution of cGnRH-II-ir fibers was basically similar to that of sGnRH-ir fibers except for the absence of their continuity between the olfactory bulbs and the pituitary. These data suggest that sGnRH and cGnRH-II are endogenous peptides and indicate the presence of multiple neuroendocrine functions in the brain of the spotted sea bass. It seems that sGnRH not only regulates GTH secretion but also functions as a neurotransmitter, whereas cGnRH-II functions only as a neurotransmitter.

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.05a
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• pp.5-5
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• 2011

The research and development of hybrid electric vehicle (HEV), plug-in hybrid electric vehicle (PHEV) and electric vehicle (EV) are intensified due to the energy crisis and environmental concerns. In order to meet the challenging requirements of powering HEV, PHEV and EV, the current lithium battery technology needs to be significantly improved in terms of the cost, safety, power and energy density, as well as the calendar and cycle life. One new technology being developed is the utilization of composite cathode by mixing two different types of insertion compounds [e.g., spinel $LiMn_2O_4$ and layered $LiMO_2$ (M=Ni, Co, and Mn)]. Recently, some studies on mixing two different types of cathode materials to make a composite cathode have been reported, which were aimed at reducing cost and improving self-discharge. Numata et al. reported that when stored in a sealed can together with electrolyte at $80^{\circ}C$ for 10 days, the concentrations of both HF and $Mn^{2+}$ were lower in the can containing $LiMn_2O_4$ blended with $LiNi_{0.8}Co_{0.2}O_2$ than that containing $LiMn_2O_4$ only. That reports clearly showed that this blending technique can prevent the decline in capacity caused by cycling or storage at elevated temperatures. However, not much work has been reported on the charge-discharge characteristics and related structural phase transitions for these composite cathodes. In this presentation, we will report our in situ x-ray diffraction studies on this mixed composite cathode material during charge-discharge cycling. The mixed cathodes were incorporated into in situ XRD cells with a Li foil anode, a Celgard separator, and a 1M $LiPF_6$ electrolyte in a 1 : 1 EC : DMC solvent (LP 30 from EM Industries, Inc.). For in situ XRD cell, Mylar windows were used as has been described in detail elsewhere. All of these in situ XRD spectra were collected on beam line X18A at National Synchrotron Light Source (NSLS) at Brookhaven National Laboratory using two different detectors. One is a conventional scintillation detector with data collection at 0.02 degree in two theta angle for each step. The other is a wide angle position sensitive detector (PSD). The wavelengths used were 1.1950 ${\AA}$ for the scintillation detector and 0.9999 A for the PSD. The newly installed PSD at beam line X18A of NSLS can collect XRD patterns as short as a few minutes covering $90^{\circ}$ of two theta angles simultaneously with good signal to noise ratio. It significantly reduced the data collection time for each scan, giving us a great advantage in studying the phase transition in real time. The two theta angles of all the XRD spectra presented in this paper have been recalculated and converted to corresponding angles for ${\lambda}=1.54\;{\AA}$, which is the wavelength of conventional x-ray tube source with Cu-$k{\alpha}$ radiation, for easy comparison with data in other literatures. The structural changes of the composite cathode made by mixing spinel $LiMn_2O_4$ and layered $Li-Ni_{1/3}Co_{1/3}Mn_{1/3}O_2$ in 1 : 1 wt% in both Li-half and Li-ion cells during charge/discharge are studied by in situ XRD. During the first charge up to ~5.2 V vs. $Li/Li^+$, the in situ XRD spectra for the composite cathode in the Li-half cell track the structural changes of each component. At the early stage of charge, the lithium extraction takes place in the $LiNi_{1/3}Co_{1/3}Mn_{1/3}O_2$ component only. When the cell voltage reaches at ~4.0 V vs. $Li/Li^+$, lithium extraction from the spinel $LiMn_2O_4$ component starts and becomes the major contributor for the cell capacity due to the higher rate capability of $LiMn_2O_4$. When the voltage passed 4.3 V, the major structural changes are from the $LiNi_{1/3}Co_{1/3}Mn_{1/3}O_2$ component, while the $LiMn_2O_4$ component is almost unchanged. In the Li-ion cell using a MCMB anode and a composite cathode cycled between 2.5 V and 4.2 V, the structural changes are dominated by the spinel $LiMn_2O_4$ component, with much less changes in the layered $LiNi_{1/3}Co_{1/3}Mn_{1/3}O_2$ component, comparing with the Li-half cell results. These results give us valuable information about the structural changes relating to the contributions of each individual component to the cell capacity at certain charge/discharge state, which are helpful in designing and optimizing the composite cathode using spinel- and layered-type materials for Li-ion battery research. More detailed discussion will be presented at the meeting.

• Journal of Sericultural and Entomological Science
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• v.6
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• pp.1-8
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• 1966

Various relationships with the leaf yield per 1,000m in the length of mulberry branch were investigated. The results obtained are as followings. 1. Relationship with the mulberry varieties. There were little differences of the leaf yield among the mulberry varieties, being 106∼109kg in an average and the distributions of the leaf yield were of 60∼160kg class for Morus bombycis Koidz, 50-17kg class for Morus Lhou(Ser.) Koidz and 50∼180kg class for Morus alba L. Otherwise, 79 per cent of all varieties was between 80∼140kg class to which 85 per cent of only Morus Lhou(Ser.) Koidz belonged. There was one or two peaks for each strains, for example, the peak at 80∼90kg class and at 120∼140kg class in Morus bombycis Koidz showed the best yield, the peak at 90∼100kg class in Morus alba L. and 100∼110kg class in Morus Lhou(Ser.) Koidz. 2. Relationship with the pruning. The multi-stemed pruning showed 149kg mulberry leaf yield which was more 75 per cent increase than the low-stemed pruning, 85kg. 3. Relationship with the degree of cutting off. The leaf yield varied according to the degree of cutting off the branch, such as, 166kg in 1/3 cutting off the branch and 180kg in $\frac{1}{2}$ which were more 19 per cent and 34 per cent increase of 140kg in non-cutting off the branch, respectively. The main cause of the leaf increase was thought because of the increase of young branch. 4. Relationship with the branch diameter. In the relation to the leaf yield per 1,000m in branch length, there was no significance comparing 66kg for thin branch with 80kg for medium one ana the thick branch had 150kg leaf yield and increased 88 per cent when compared with the medium one. In the relation to the leaf yield per l0cm in diameter, 811g leaves for thin branch and 875g for medium one were produced, but there was no significance between them. Thick branch had 1,461g, and increased 67 per cent when compared with medium one and the average yield was 1,201g for total branch.

• Clean Technology
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• v.17 no.2
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• pp.124-133
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• 2011

In addition to six substances regulated in EU RoHS including lead, mercury, cadmium, hexavalent chromium, polybrominated biphenyls (PBB) and polybrominated diphenyl ethers (PBDE), priority substances are identified in new RoHS II as hexabromocyclododecane (HBCDD), dibutyl phthalate (DBP), butyl benzyl phthalate (BBP) and diethylhexyl phthalate (DEHP). In this study, 20 plastic samples were collected from 12 domestic electrotechnical companies and levels of four restricted substances were determined by gas chromatography-mass spectrometry, Among 20 parts that compose washer, refrigerator or microwave oven, HBCDD was detected in three samples of NBR material with the amount of 42~381 mg/kg while DBP and BBP was not detected in any samples collected respectively, implying that these substance may not be used widely in plastic materials for EEE. However, DEHP was detected in all samples of NBR, PP, PBT, EPDM and PVC materials with the amount of 42 up to 59,400 mg/kg that exceeds the limit value of 0.1 wt% (1,000 mg/kg). Presence of a restricted substance in polymer material makes a great negative influence on a number of final product. To cope with coming RoHS II as well as REACH, action not to use DEHP in plastic material or the relevant notification in case of REACH seems to be needed. Screening test of Arsenic compounds such as diarsenic pentaoxide, diarsenic trioxide, lead hydrogen arsenate, triethyl arsenate that are included in REACH SVHC was done by ICP measurement Arsenium was detected in four samples made of NBR and PBT materials in the level of 15~700 mg/kg. By considering the screening method used in this study, the amount of arsenium compounds in the thermistor made of PBT material has a high chance of exceeding the regulated limit value.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.11
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• pp.1554-1558
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• 2012

Method development and validation of ellagic acid for the standardization of Gochang Bokbunja as a functional ingredient and health food were accomplished. A Symmetry$^{(R)}$ (C18, $4.6{\times}250mm$, $5.0{\mu}m$) column was used with a gradient elution system of 1% formic acid in water and acetonitrile. This method was validated according to specificity, linearity, accuracy, precision test, and recovery test. Specificity was confirmed with identical retention time, and calibration curves of ellagic acid showed good linear regression ($R^2$ >0.9996). Relative standard deviations (RSD) of data from the intra- and inter-day experiments were less than 2.28% and 2.84%, except in the low limit of quality control (LLOQ, $1{\mu}g/mL$) sample. The results of the recovery test were from 89.17% to 97.92% with RSD values from 0.05 to 0.14%. Therefore, we performed analysis of ellagic acid as a marker compound in Gochang Bokbunja extracts. The amount of ellagic acid in Gochang Bukbunja was about $1.918{\mu}g/mg$ (0.192%) in the three times analysis, and RSD was less than 2.36% by the validated method. These results suggest that the developed HPLC method is simple, efficient, and could contribute to the quality control of Gochang Bokbunja extract as a functional ingredient.

• Journal of the Korean Electrochemical Society
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• v.20 no.4
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• pp.67-74
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• 2017

Layered Ni-rich NCM cathode materials $Li[Ni_xCo_{(1-x)/2}Mn_{(1-x)/2}]O_2$ ($x{\geq}0.6$) have advantages of high energy density and cost competitive over $LiCoO_2$. The discharge capacity of NCM increases proportionally to the Ni contents. However, there is a problem that it is difficult to realize the stable electrochemical performance due to cation mixing. In this study, synthesis conditions for the layered Ni-rich NCMs are investigated to achieve deliver the ones having good electrochemical performances. Synthesis parameters are atmosphere, lithium source, synthesis time, synthesis temperature and Li/M (M=transition metal) ratio. The degree of cation mixing gets worse as the Ni content is increased from $Li[Ni_{0.6}Co_{0.2}Mn_{0.2}]O_2$ (NCM6) to $Li[Ni_{0.8}Co_{0.1}Mn_{0.1}]O_2$ (NCM8). It is confirmed that higher level of cation mixing affects negatively on the electrochemical performance of NCMs. Optimum synthesis conditions are explored for NCMx (x=6, 7, 8) in order to reduce the cation mixing. Under optimized conditions for three representative NCMx, a high initial discharge capacity and a good cycle life are obtained for $180mAh{\cdot}g^{-1}$, 96.2% (50 cycle) in NCM6, $187mAh{\cdot}g^{-1}$, 94.7% (50 cycle) in NCM7, and $201mAh{\cdot}g^{-1}$, 92.7% (50 cycle) in NCM8, respectively.

• Korean journal of communication and information
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• v.43
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• pp.385-426
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• 2008

This paper focuses on how international marriages among Asians have been represented by the Korean media. Due to globalization, the so-called 'ethnoscape' has changed, and so ethnicity or racial identity within the boundaries of the nation-state changed. The recent diaspora of Asian women into Korea through international marriages has reflected how globalization has proceeded at a regional or local level. This paper attempts to analyze Koreanmedia discourses on the Asian female diaspora. This study analyzes what kind of generic forms TV dramas, other shows(TV reality programs, TV journalistic programs), movie and internet have employed to represent international marriages and how they have portrayed the subjectivities of the Asian female diaspora. This study discuss how this representation has been contested by the 'realities' of their international marriages. By examining how the Korean mainstream media have dealt with the conflicting issues of the Asian female diaspora, this paper intends to look critically at how local discursive practices have substantiated the changing ethnoscape. As a result of the study, this paper can find international marriages among Asians have been represented by Korean media still patriarchal system in male-oriented society. The otherness of Asian women justify the strong work of household affairs, and so justified life is standardized 'a kind of daughter- in-law', 'a complaisant daughter-in-law' in the process of migration. Also the otherness of Asian women standardized 'a victor' or 'a harmer' through international marriage of money that commercialized 'sexuality'. After all Korea media discourse on Asian women's international marriage, the gender issues on it have not been focused on a serious level.

• Journal of the Korean earth science society
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• v.41 no.5
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• pp.469-477
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• 2020

Salinity is not only an important variable that determines the density of the ocean but also one of the main parameters representing the global water cycle. Ocean salinity observations have been mainly conducted using ships, Argo floats, and buoys. Since the first satellite salinity was launched in 2009, it is also possible to observe sea surface salinity in the global ocean using satellite salinity data. However, the satellite salinity data contain various errors, it is necessary to validate its accuracy before applying it as research data. In this study, the salinity accuracy between the Soil Moisture Active Passive (SMAP) satellite salinity data and the in-situ salinity data provided by the Ieodo ocean research station was evaluated, and the error characteristics were analyzed from April 2015 to August 2020. As a result, a total of 314 match-up points were produced, and the root mean square error (RMSE) and mean bias of salinity were 1.79 and 0.91 psu, respectively. Overall, the satellite salinity was overestimated compare to the in-situ salinity. Satellite salinity is dependent on various marine environmental factors such as season, sea surface temperature (SST), and wind speed. In summer, the difference between the satellite salinity and the in-situ salinity was less than 0.18 psu. This means that the accuracy of satellite salinity increases at high SST rather than at low SST. This accuracy was affected by the sensitivity of the sensor. Likewise, the error was reduced at wind speeds greater than 5 m s^-1. This study suggests that satellite-derived salinity data should be used in coastal areas for limited use by checking if they are suitable for specific research purposes.

• Journal of the Korean Electrochemical Society
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• v.19 no.3
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• pp.80-86
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• 2016

High Ni content layered oxide materials for the positive electrode in lithium-ion batteries have high specific capacity. However, their poor electrochemical and thermal stability at elevated temperature restrict the practical use. A small amount of $Al_2O_3$ was added to the mixture of transition metal hydroxide and lithium hydroxide. The $LiNi_{0.6}Co_{0.2}Mn_{0.2}O_2$ was simultaneously doped and coated with $Al_2O_3$ during heat-treatment. Electrochemical characteristics of modified $LiNi_{0.6}Co_{0.2}Mn_{0.2}O_2$ were evaluated by the galvanostatic cycling and the LSTA(linear sweep thermmametry) at the constant voltage conditions. The nano-sized $Al_2O_3$ added materials show better cycle performance at elevated temperature than that of micro-sized $Al_2O_3$. As the added amount of nano-$Al_2O_3$ increased, the thermal stability of electrode also enhanced, but the use of 2.5 mol% Al showed the best high temperature performance.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.20 no.5
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• pp.408-418
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• 1987

The quality of different grades of dried lavers obtained from three culture areas was evaluated and its changes during the storage at different levels of water activity were measured. Not much differences in general chemical composition between the locality was detected except some in the content of lipid and pigments. But the quality grades of dried lavers were mainly depended upon the content of protein and pigments including chlorophyll a, carotenoids, and biliproteins although there was little difference in amino acid composition of the proteins, and glutamic acid, aspartic acid and alanine were high in general. The lipid of dried lavers was composed of a high level of polyunsaturated fatty acids, particularly, of eicosapentaenoic acid which amounted to as much as a half of the total lipid, and of palmitic acid that reached a quarter depending on grades. The quality of dried layers was significantly changed by equilibrium moisture level when stored for three months at different water activities in range of 0.1 to 0.6. The loss of chlorophyll a, carotenoid, biliproteins, ascorbic acid, and browning were markedly retarded at aw 0.1 to 0.2. Oxidation of polyunsaturated fatty acids and the loss of free amino acids were also minimized at aw 0.2. Glutamic acid and methionine were reduced very fast during the storage.