• International Journal of Ocean System Engineering
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• v.2 no.3
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• pp.185-194
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• 2012

A Macroscopic combination of two or more distinct materials is commonly referred to as a "Composite Material", having been designed mechanically and chemically superior in function and characteristic than its individual constituent materials. Composite materials are used not only for aerospace and military, but also heavily used in boat/ship building and general composite industries which we are seeing increasingly more. Regardless of the various applications for composite materials, the industry is still limited and requires better fabrication technology and methodology in order to expand and grow. An example of this is that the majority of fabrication facilities nearby still use an antiquated wet lay-up process where fabrication still requires manual hand labor in a 3D environment impeding productivity of composite product design advancement. As an expert in the advanced composites field, I have developed fabrication skills with the use of machinery based on my past composite experience. In autumn 2011, the Korea government confirmed to fund my project. It is the development of a composite sanding machine. I began development of this semi-robotic prototype beginning in 2009. It has possibilities of replacing or augmenting the exhaustive and difficult jobs performed by human hands, such as sanding, grinding, blasting, and polishing in most often, very awkward conditions, and is also will boost productivity, improve surface quality, cut abrasive costs, eliminate vibration injuries, and protect workers from exposure to dust and airborne contamination. Ease of control and operation of the equipment in or outside of the sanding room is a key benefit to end-users. It will prove to be much more economical than normal robotics and minimize errors that commonly occur in factories. The key components and their technologies are a 360 degree rotational shoulder and a wrist that is controlled under PLC controller and joystick manual mode. Development on both of the key modules is complete and are now operational. The Korean government fund boosted my development and I expect to complete full scale development no later than 3rd quarter 2012. Even with the advantages of composite materials, there is still the need to repair or to maintain composite products with a higher level of technology. I have learned many composite repair skills on composite airframe since many composite fabrication skills including repair, requires training for non aerospace applications. The wind energy market is now requiring much larger blades in order to generate more electrical energy for wind farms. One single blade is commonly 50 meters or longer now. When a wind blade becomes damaged from external forces, on-site repair is required on the columns even under strong wind and freezing temperature conditions. In order to correctly obtain polymerization, the repair must be performed on the damaged area within a very limited time. The use of pre-impregnated glass fabric and heating silicone pad and a hot bonder acting precise heating control are surely required.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.2
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• pp.225-234
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• 2009

The aim of this study was to analyze moisture, crude protein, crude lipid, vitamin C and sugar changes in selected Korean chestnut cultivars such as Danteack, Deabo, Seokchu, Okkwang and Byunggo during storage at $4^{\circ}C$ and $-10^{\circ}C$ for 10 months. The moisture contents of selected Korean chestnut cultivars ranged from 49.9 to 57.4%. The moisture content of Seokchu was the highest. The contents of moisture in white kernel were higher than that in yellow kernel. The content of moisture showed decreasing tendency after 10 months of storage. The crude protein and crude lipid contents in whole kernel of selected Korean chestnut cultivars were $3.3{\sim}4.2%$ and $0.3{\sim}1.6%$, respectively. The crude protein content of Deabo was the highest. The crude protein in Danteack, Seokchu, Okkwang and Byunggo was increased during storage at $4^{\circ}C$ for 10 months, while that in whole kernel of Deabo was decreased and no changes in crude protein in yellow kernels of Deabo were observed. The crude protein in Okkwang was increased during storage at $-10^{\circ}C$ for 10 months. The cold storage was found to have higher composition change of crude protein than the freezing storage. The content of crude lipid in Daebo and Byunggo was decreased during storage at $4^{\circ}C$ and $-10^{\circ}C$. Yellow kernels of Deabo, Okkwang and Byunggo were found to have higher crude lipid content than white kernels. The vitamin C content also decreased during storage at $4^{\circ}C$ and $-10^{\circ}C$ and the decrease in vitamin C content was higher at $4^{\circ}C$ than $-10^{\circ}C$. Vitamin C was not detected after 3 months storage at $-10^{\circ}C$. The sugar content increased at the latter period storage at $4^{\circ}C$ and $-10^{\circ}C$. The sugar content of selected Korean chestnut cultivars ranged from $36.2{\sim}44.3%$ and Dantaek had the highest sugar content.

• Korean Journal of Soil Science and Fertilizer
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• v.23 no.4
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• pp.287-292
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• 1990

A study has been conducted since 1954 to elucidate the effects of longterm application of ammonium sulfate (AS), urea, compost, and calcium silicate(CS) fertilizers on major soil nutrients and rice yields in wetland soil. The soil pH in the AS plot become lower than that in the urea plot but had little influence on rice yield. Continuous application of AS and urea with compost and CS raised the soil pH compared with single applications of AS or urea. Soil organic matter content increased yearly in plot with no fertilizer and in those with AS and urea, and increased considerably in plots with compost and CS. Application of compost and CS promoted rice top growth as well as root growth, resulting in increased dry matter. Soil contents of N, $P_2O_5$, Ca, Mg, and $SiO_2$ in the NPK with composts plot increased considerably compared with the NPK plot; however. the exchangeable K content was rather low. Rice growth increased with compost application. which enhanced K uptake, and the coarse texture promoted K leaching. With compost and CS addition, con tents of exchangeable Ca and Mg in the AS plot decreased considerably more than in the urea plot. Probably this was the result of higher Ca and Mg precipitation by sulfate in the AS plot. The re are no significant differences in rice yield between AS and urea plots. With compost and CS treatments, rice yields increased in the AS plot compared with the urea plot. The increase in yield is considered to be the effect of S. which is a constituent of AS.

• Development and Reproduction
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• v.15 no.2
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• pp.179-185
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• 2011

Some phytoestrogens in soy and red wine, for example, might have beneficiary rather than adverse effects. In particular, dietary soy intake seems to be highly correlated with protection of breast cancer, osteoporosis and cardiovascular disorders. However, questions persist on the potential adverse effects of the main soy constituent genistein (GS) on female reproductive physiology. Previously we found that prepubertal exposure to GS could activate the reproductive system of immature female rats leading to precocious puberty onset, and intracerebroventricularly (ICV) injected GS could directly activate hypothalamic kisspeptin-GnRH neuronal circuits in adult female rats. The present study was performed to examine the hypothalamus-specific GS effects in prepubertal female rats and which subtype of estrogen receptor is mediated in this GS effect. Prepubertal female rats (PND 30) were anaesthetized, treated with single dose of GS (3.4 ${\mu}g$/animal), and sacrificed at 2 hrs post-injection. To determine the transcriptional changes of reproductive hormone-related genes in hypothalamus, total RNAs were extracted and applied to the semi-quantitative reverse transcription polymerase chain reaction (RT-PCR). ICV infusion of GS significantly lowered the transcriptional activities of mTOR (1:$0.361{\pm}0.058$ AU, p<0.001) but increased that of GAD67 (1:$1.285{\pm}0.099$ AU, p<0.05), which are known to act as an upstream modulator of kisspeptin and GnRH neuronal activities in the hypothalamus, respectively. GS administration enhanced significantly the mRNA levels of KiSS-1(1:$1.458{\pm}0.078$ AU, p<0.001), and exerted no effect on the mRNA level of kisspeptin receptor GPR-54 (1:$1.29{\pm}0.08$ AU). GnRH gene expression was significantly decreased in GS-treated group compared to control group (1:$0.379{\pm}0.196$ AU, p<0.05). There was no difference in the mRNA level of $ER{\alpha}$ in the GS-treated group compare to control group (1:$1.180{\pm}0.390$ AU, Fig. 3A). However, icv infusion of GS significantly increased the transcriptional activities of $ER{\beta}$ (1:$4.209{\pm}0.796$ AU, p<0.01, Fig. 3B). Taken together, the present study indicated that the acute exposure to GS could directly alter the hypothalamic GnRH modulating system in prepubertal female rats. Our study strongly suggested the involvement of $ER{\beta}$ pathway in GS's hypothalamus-specific action, and this idea is consistent with the GS's well-known $ER{\beta}$-mediated protective action in breast cancer.

• Applied Biological Chemistry
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• v.48 no.3
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• pp.267-272
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• 2005

trans-Cinnamaldehyde, a major component of Cinnamomum cassia, was quantitatively analyzed using the $^1H-NMR$ spectrometry. Applicability of this method was confirmed through observing the variation of chemical shift in the $^1H-NMR$ spectrum of t-cinnamaldehyde and the integration value according to various sample concentrations or running temperatures. When the $^1H-NMR$ spectrometry was run for t-cinnamaldehyde (7.1429 mg/ml) at 19, 25, 30, 40 and $50^{\circ}C$, the chemical shifts of the doublet methine signal due to an aldehyde group were observed at 9.7202, 9.7184, 9.7169, 9.7142 and 9.7124 ppm, respectively, to imply that the running temperature had no significant variation in the chemical shift of the signal. The integration values of the signal were $1.37\;(19^{\circ}C),\;1.37\;(25^{\circ}C),\;1.37\;(30^{\circ}C),\;1.37(40^{\circ}C)$ and $1.37(50^{\circ}C)$, respectively, to also indicate running temperature gave no effect on the integration value. When the sample solutions with various concentrations such as 0.4464, 0.8929, 1.7857, 3.5714, 7.1429 and 14.286 mg/ml were respectively measured for the $^1H-NMR$ at $25^{\circ}C$, the chemical shifts of the aldehyde group were observed at 9.7206, 9.7201, 9.7196, 9.7192, 9.7185 and 9.7174 ppm. Even though the signal was slightly shifted to the high field in proportion to the increase of sample concentration, the alteration was not significant enough to applicate this method. The calibration curve for integration values of the doublet methine signal due to the aldehyde group vs the sample concentration was linear and showed very high regression rate ($r^2=1.0000$). Meantime, the $^1H-NMR$ spectra (7.1429 mg/ml $CDCl_3,\;25^{\circ}C$) of t-cinnamaldehyde and t-2-methoxycinnamaldehyde, another constituent of Cinnamomum cassia, showed the chemical shifts of the aldehyde group as ${\delta}_H$ 9.7174 (9.7078, 9.7270) for the former compound and ${\delta}_H$ 9.6936 (9.6839, 9.7032) for the latter one. The difference of the chemical shift between two compounds was big enough to be distinguished using the NMR spectrometer with 0.45 Hz of resolution. The contents of cinnamaldehyde in Cinnamomum cassia, which were respectively extracted with n-hexane, $CHCl_3$, and EtOAc, were determiend as 94.2 \;mg/g (0.94%), 137.6 mg/g (1.38%) and 140.1 mg/g(1.40%) t-cinnamaldehyde in each extract, respectively, by using the above method.

• Applied Microscopy
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• v.30 no.1
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• pp.45-59
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• 2000

Cis-platin is a widely used anticancer drug against certain solid tumors such as malignant ovarian tumor, malignant carcinoma of head and neck, bladder cancer and cervical cancer of uterus, and its major mechanism of action is inhibition of DNA synthesis of the tumor cell. To investigate the inhibitory effects of cis-platin on the ciliogensis of the ciliated cells in the mucosa of oviduct, the author pursued the alterations of $\alpha-tubulin$, which is the main constituent of the microtubles in cilia, after cis-platin treatment. To eliminate the possible variations due to ovarian cycle, female Spargue-Dawley rats ($150\sim200gm$ in B.W.) were pretreated with estradiol benzoate (20 mg/kg, once a day, for 4 consecutive days). Animals were administrated with cis-platin (6 mg/kg, i.p.) and sacrificed at 1day, 3days, 5days and 7days after treatment, respectively. Immunohistochemistry for $\alpha-tubulin$ using mouse anti-rat $\alpha-tubulin$ monoclonal antibody as primary antibody was done. Immunogold electronmicroscopy for intracellular distributions of $\alpha-tubulin$ was also performed with same primary antibody and Goat anti- mouse IgM which is preconjugated with gold particles of 15 nm as secondary antibody. The results obtained were as follows; 1. Strong immunoreactivity of $\alpha-tubulin$ was observed in ciliated cells of oviducts at 1, 3 and 5 days after estradiol pretreatment. 2. Weak immunoreactivity of $\alpha-tubulin$ was observed in ciliated cells of oviducts at 1 and 3 days after cis-platin treatment but it was recovered to strong immunoreactivity in 5 days 3. In immunogold electronmicroscopy, density of gold particles for $\alpha-tubulin$ reactions was decreased in apical cytoplasm, but few changes were observed in basal body or cilia at 1 and 3 days after cis-platin treatment. From these above results, it is indicated that synthesis of $\alpha-tubulin$ in ciliated cells of rat oviduct is inhibited by cis-platin treatment.

• Korean Journal of Food Science and Technology
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• v.14 no.2
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• pp.97-105
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• 1982

The edible portion of chestnut, Castenea crenata Sieb, et Zucc, were freeze-dried and subjected to analysis of minerals, lipid classes and fatty acid composition by silicic acid column chromatography and gas-liquid chromatography. The results of analysis for the minerals in chestnut showed that the contents of magnesium, iron and phosphorus were decreased during storage after freeze-drying. The contents of neutral lipids, glycolipids and phospholipids in the raw edible portion were 34.6, 38.6, and 26.8%, respectively. The contents of neutral lipids and phospholipids of the freeze-dried chestnut were decreased, while glycolipids were increased during storage. In the fatty acid composition of total lipid, $C_{16:0}$, $C_{18:2}$ and $C_{18:3}$ acid were abundant in the raw edible portion, but freeze-dried chestnut contained relatively much amount of $C_{16:0}$, $C_{18:1}$, and $C_{18:2}$ acid. It is noticeable that $C_{18:2}$ and $C_{18:3}$ acid in the freeze-dried chestnut were remarkably decreased during storage. Upon the fatty acid composition, total lipid contained $C_{18:2}$ and $C_{16:0}$ acid in the highest proportion, but neutral lipids, glycolipids and phospholipids contained $C_{16:0}$ and $C_{18:2}$ acid in the highest proportion. Cycloartenol (20.6%) was a major component in the 4-monomethylsterol fraction separated by thin layer chromatography and cyclolaudenol, cycloeucalenol, and citrostadienol were detected as minor components. Sitosterol (74.6%) was a major component in the 4-desmethylsterol fraction separated by thin-layer chromatography and ${\Delta}^5-avensterol$, campesterol, stigmasterol and brassicasterol were also detected as minor components.

• Korean Journal of Cognitive Science
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• v.2 no.2
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• pp.405-428
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• 1990

Language has a social function to communicate information. Linguists have gradually paid their attention to the function of language since the nineteen sixties, especially to the relationship of form, meaning and the function. The relationship could be more clearly grasped through disciyrse-based analysis than through sentence-based analysis. Many researches were centered on the discourse functional notion of topic. In the early 1970's the subject was defined as the grammatiocalized topic the topic as a discrete single constituent of the clause. In the late 1970's several lingusts including Givon suggerted that the topic was not an atomic, disctete entity, and that the clause could have more than one topic. The purpose of the present study is, following Givon, to study grammatical coding devices of topic and to measure the relative topic continuity/discontinuity of participant argu, ents in Korean narratives. By so doing, I would like to shed some light on effective ways of communicating information. The grammatical coding devices analyzed are the following eight structures: zero-anaphora, personal pronous, demonstrative pronouns, names, noun phrases following demonstratives, noun phrases following possessives, definite noun phrases and indefinite referentials. The narrative studied for the count was taken from the KoreanCIA chief's Testiomny:Revolution and Idol by Hyung Wook Kim. It was chosen because it was assumed that Kim's purpose in the novel was to tell a true story, which would not distort the natural use of language for literary effect. The measures taken in the analysis wre those of 'lookback', 'persistence', ambiguity'. The first of these, 'lookback', is a measure of the size of gap between the previous occurrence of a referent and its current occurence in the clause. The meausure of persistence, which is a measure of the speaker's topocal intent, reflects the topic's importance in the discourse. The third measure is a measure of ambiguity. This is necessary for assessing the disruptive effects that other topics within five previous clauses may have on topic identification. The more other topics are present within five previous clauses, the more difficult is the task of correct identification of a topic. The results of the present study show that the humanness of entities is the most powerful factior in topic continutiy in narrative discourse. The semantic roles of human arguments in narrative discourse tend to be agents or experiences. Since agents and experiences have high topicality in discourse, human entities clearly become clausal or discoursal topics. The results also show that the grammatical devices signal varying degrees of topic continuity discontinuity in continuous discourse. The more continuous a topic argument is, the less it is coded. For example, personal pronouns have the most continutiy and indefinite referentials have the least continutiy. The study strongly shows that topic continuity discontinutiy is controlled not only by grammatical devices available in the language but by socio-cultural factors and writer's intentions.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.4
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• pp.413-433
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• 1994

Jinhae Bay once was a productive area of fisheries. It is, however, now notorious for its red tides; and oxygen deficient water-masses extensively develop at present in summer. Therefore the shellfish production of the bay has been decreasing and mass mortality often occurs. Under these circumstances, the three-dimensional numerical hydrodynamic and the material cycle models, which were developed by the Institute for Resources and Environment of Japan, were applied to analyze the processes affecting the oxygen depletion and also to evaluate the environment capacity for the reception of pollutant loads without dissolved oxygen depletion. In field surveys, oxygen deficient water-masses were formed with concentrations of below 2.0mg/l at the bottom layer in Masan Bay and the western part of Jinhae Bay during the summer. Current directions, computed by the $M_2$ constituent, were mainly toward the western part of Jinhae Bay during flood flows and in opposite directions during ebb flows. Tidal currents velocities during the ebb tide were stronger than that of the flood tide. The comparision between the simulated and observed tidal ellipses showed fairly good agreement. The residual currents, which were obtained by averaging the simulated tidal currents over 1 tidal cycle, showed the presence of counterclockwise eddies in the central part of Jinhae Bay. Density driven currents were generated southward at surface and northward at the bottom in Masan Bay and Jindong Bay, where the fresh water of rivers entered. The material cycle model was calibrated with the data surveyed in the field of the study area from June to July, 1992. The calibrated results are in fairly good agreement with measured values within relative error of $28\%$. The simulated dissolved oxygen distributions of bottom layer were relatively high with the concentration of $6.0{\sim}8.0mg/l$ at the boundaries, but an oxygen deficient water-masses were formed within the concentration of 2.0mg/l at the inner part of Masan Bay and the western part of Jinhae Bay. The results of sensitivity analyses showed that sediment oxygen demand(SOD) was one of the most important influence on the formation of oxygen depletion. Therefore, to control the oxygen deficient water-masses and to conserve the coastal environment, it is an effective method to reduce the SOD by improving the polluted sediment. As the results of simulations, in Masan Bay, oxygen deficient water-masses recovered to 5.0mg/l when the $50\%$ reduction in input COD loads from Masan basin and $70\%$ reduction in SOD was conducted. In the western part of Jinhae Bay, oxygen deficient water-masses recovered to 5.0mg/l when the $95\%$ reduction in SOD and $90\%$ reduction in culturing ground fecal loads was conducted.

• Resources Recycling
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• v.23 no.2
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• pp.17-25
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• 2014

The thermal effect on the compositional change of the $SO_2$ absorption process product was investigated compared with the composition of raw material when dolomite is employed in place of lime in the scrubbing process based on thermodynamic estimation. It was considered that the equilibrium reactions which directly related with the formation of $CaSO_4$ and $MgSO_4$, the absorption process products, are those between $Ca^{2+}$ and $Ca(OH)_2$, $Mg^{2+}$ and $Mg(OH)_2$, and the secondary dissociation reaction of $H_2SO_4$. It was thought to be necessary to examine the enthalpy change for the formation reactions of $CaSO_4$ and $MgSO_4$ along with the thermal feature of the relative reactions to figure out the influence of temperature on the compositional change of absorption process products. The stable regions for $Ca(OH)_2$ and $Mg(OH)_2$ in Pourbaix diagram were found to be increased as temperature rises and the equilibrium reaction between $Ca^{2+}$ and $Ca(OH)_2$ was investigated to be more strongly influence by temperature change compared with the equilibrium reaction between $Mg^{2+}$ and $Mg(OH)_2$. The amounts of $CaSO_4$ and $MgSO_4$ were anticipated to be decreased with temperature considering the thermal characteristics for the equilibrium reactions regarding calcium, magnesium, and $H_2SO_4$. It was understood that the formation ratio between $CaSO_4$ and $MgSO_4$ is greater than the composition ratio between calcium and magnesium contained in dolomite at specific temperature and the decrease of the formation ratio of $CaSO_4$ and $MgSO_4$ with temperature was estimated to be diminished as the content of calcium in dolomite is increased. In addition, the extent of the change in the compositional ratio between absorption process products was examined to be reduced compared with the composition of raw material as the calcium content in dolomite is raised.