• Korean Journal of Fisheries and Aquatic Sciences
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• v.25 no.1
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• pp.15-28
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• 1992

Temporal variations of the path of the East Korea Warm Current(EKWC) which flows northward along the east coast of Korea were analysed to investigate whether the EKWC directly influences the existence of the so-called Warm Core in the Ulreung basin. From the 13 years(1975-1987) data of the Fisheries Research and Development Agency(FRDA), the $10^{\circ}C$ isotherm at the 100m depth and the depth of $2^{\circ}C$ isotherm and the temperature field at the 200m depth were used for identification of the path and the central position of the Warm Core. Sea surface winds computed from the surface pressure charts gave the monthly-averaged wind stress curl over the East Sea which was used for determination of the Sverdrup transport. And the mass transport stream functions were computed by use of the Sverdrup balance. The variations of the path show that the EKWC does not always have a fixed path and fluctuates with time. And the existence of the Warm Core is independent upon the presence of the EKWC even when the EKWC doesn't flow northward along the east coast of Korea. In view of the mass transport stream functions, the influences of the sea surface winds on the branching of the Tsushima Warm Currents and the presence of the EKWC were investigated. The presence of the EKWC may be hindered by the southward flow driven by the sea surface winds when the Tsushima currents are rather weak. A very weak correlation exists between the north-south component of the Sverdrup transport and the position of the Warm Core. However, a small but significant part of the southward transport across the latitudinal line of $38^{\circ}N$ indicates that cold water from the northern part of the East Sea may be driven and be forced to flow beneath the permanent thermocline in such a way that the thermal structure of the Warm Core and its position might be changed.

• Proceedings of the KIPE Conference
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• 2009.11a
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• pp.105-110
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• 2009

The On Line Electric Vehicles(OLEV) that can pick up inductive power from underground coils on driving with high efficiency have been developed this year, and is now proposed in this paper. The IPS(Inductive Power Supply) system consists of power supply inverters, power supply rails, pick up modules, and a regulator. There are 3 generations of IPS have been developed so far, and the $4^{th}$ generation IPS is being developed. The $1^{st}$ generation has been demonstrated this Feb. 27, which is equipped with mechanically auto tracking pick-up module with 1cm air gap, and showed 80% power efficiency. The $2^{nd}$ generation IPS applied to an 120kW (average)/240kW(peak) motor powered electric bus has 17cm air gap with 72% power efficiency. For the $2^{nd}$ generation IPS, the Power supply inverter has 440V, 3phase input and 200A @ 20kHz output. The test power supply rail of 240m long is segmented by 60m each, where newly developed core structure and power cable are constructed under the road covered with asphalt of 5cm thickness. The pick-up modules which consist of core, winding wire, and rectifiers are fixed to the bottom of the bus which can carry more than 40 passengers and can pick up max. 60kW. To remove parasitic component and to transfer maximum power between them resonant circuit topology is applied to the primary and secondary sides. The EMF level is below 62.5mG at 1.75m from the center of the road to meet the regulation. Several effective ways of reducing EMF levels have been developed. In addition, effective ways to solve problems related high frequency power cables buried in ground and it's proof from soil have been studied also. This development shows that the IPS system is capable of supplying enough power to the pick-up of OLEV and can reduce battery size, weight and cost, which means the IPS with OLEV is one of the best candidate for EV.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.3
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• pp.288-295
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• 1999

Nineteen japonica and Tongil-type rices were selected from seventy nine Korean and Japanese rice cultivars grown in 1989 based on the water uptake behavior of milled rice under the room temperature and boiling conditions. The selected rice cultivars were investigated for water absorbability and some physicochemical characteristics of milled rice, proper water amount for cooking and sensory evaluation of cooked rice. The relationships among the tested grain properties were also examined. The highest varietal variation of water uptake rate was observed at twenty minutes after soaking in water. The maximum water uptake of milled rices at room temperature occurred mostly at about eighty minutes after soaking in water. Newly harvested rices showed a significantly lower water uptake rate of milled rice at 20 minutes after soaking, a relatively higher maximum water absorption ratio under the room temperature, and the less water uptake and volume expansion of boiled rice compared with the one-year old rice samples. The water uptake rate and the maximum water absorption ratio showed significantly negative correlations with the K/Mg ratio and alkali digestion value(ADV) of milled rice. The rice materials showing the higher amount of hot water absorption exhibited the larger volume expansion of cooked rice. The harder rices with lower moisture content revealed the higher rate of water uptake at twenty minutes after soaking and the higher ratio of maximum water uptake under the room temperature condition. These water uptake characteristics were not associated with the protein and amylose contents of milled rice ansd the palatability of cooked rice. The water/rice ratio(in w/w basis) for optimum cooking was averaged to 1.52 in dry milled rices (12% wet basis) with varietal range from 1.45 to 1.61 and the expansion ratio of milled rice after proper boiling was averaged to 2.63(in v/v basis). The water amount needed for optimum cooking was the lowest in Cheongcheongbyeo (Tongil-type rice) and the highest in Jinbubyeo, and the amount could be estimated with about 70% fittness by the multiple regression formula based on some water uptake characteristics, ADV and amylose content of milled rice as the independent variables. Nineteen rice cultivars were classified into seven groups based on scatter diagram projected by principal component analysis using eight properties related to water uptake and gelatinization of milled rice.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.3
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• pp.232-237
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• 2003

Benzyladenopuyine (BA) commonly used for soybean sprout production is of high price. The study was carried out to determine the effect of BA treatment time during seed imbibition on growth and development of soybean sprouts and to analyse its treatment cost. The soybean seeds of 4 cultivars were soaked in 4 ppm BA solution during the first 5.5 hour imbibition (EFHI), the second 5.5 hour imbibition (SFHI) immediately after 0.5 hour aeration, or whole 11.0 hour imbibition (WFHI) intervened by aeration. On the 6th day after culture, the soybean sprouts were classified into 4 categories on the base of hypocotyl length; ＞ 7cm, 4 to 7cm, ＜ 4 cm and not germinated, and their morphological characters, fresh and dry weights were measured. Water absorption of the seeds was sharply reduced after it was almost done for the first 5.5 hours. The percentage of sprouts with hypocotyls of longer than 4cm was higher in FFHI treatment than in the other two ones. Regardless of BA imbibition time and periods, the lateral roots were not observed. WFHI treatment showed shorter hypocotyl and root lengths but thicker hypocotyl and hook diameters than FFHI and SFHI treatments. All component fresh and dry weights except cotyledon fresh weight were nearly same. Treatment cost of BA was the lowest in SFHI treatment. It is concluded that BA treatment during SFHI is the best time because its treatment time did not affect sprout growth but its treatment cost.

• Development and Reproduction
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• v.15 no.3
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• pp.265-272
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• 2011

It is well known that adipose tissue or body fat has been proved as a crucial component of brain-peripheral axis which can modulate the activities of reproductive hormonal axis in female mammals including rodents and human. Concerning the male reproduction, however, the role of adipose tissue has not been thoroughly studied. The present study was carried out to elucidate the effect of a high-fat (HF) diet on the reproductive system of postpubertal male rats. The HF diet (45% energy from fat, HF group) was applied to male rats from week 8 after birth for 4 weeks. The blood glucose levels, body and tissue weights were measured. Histological studies were performed to assess the structural alterations in the reproductive tissues. To determine the transcriptional changes of reproductive hormone-related genes in hypothalamus and pituitary, total RNAs were extracted and applied to the semi-quantitative reverse transcription polymerase chain reaction (RT-PCR). Body weights (p<0.01) and blood glucose levels (p<0.01) of HF group were significantly higher than those of control animals. Similarly, the weights of epididymis (p<0.05), prostate (p<0.01), seminal vesicle (p<0.01) in HF group were higher than control levels. The weights of testis were not changed. The weights of kidney (p<0.001) and spleen (p<0.01) were significantly higher than control levels while the adrenal and pancreas weights were not changed. There were only slight alterations in the microstructures of accessory sex organs; the shape of luminal epithelial cells in epididymis from HF group were relatively thicker and bigger than those from control animals. In the semi-quantitative RT-PCR studies, the mRNA levels of hypothalamic GnRH (p<0.05) in HF group were significantly higher than those from the control animals. The mRNA levels of kisspeptin in HF group tend to be higher than control levels, the difference was not significant. Unlike the hypothalamic GnRH expression, the mRNA levels of pituitary $LH{\beta}$ and $FSH{\beta}$ were significantly decreased in HF group (p<0.05). The present study indicated that the 4-weeks feeding HF diet during the postpubertal period can alter the hypothalamus-pituitary (H-P) neuroendocrine reproductive system These results suggest that the increased body fat and the altered leptin input might disturb the H-P reproductive hormonal activities in male rats, and the changed activities seem to be responsible for the changes of tissue weights in accessory sex organs.

• Microbiology and Biotechnology Letters
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• v.17 no.5
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• pp.481-488
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• 1989

A serum-free medium that could be used for the large-scale culture of mouse hybridoma to produce monoclonal antibodies was developed. The medium was based on a 1:1 mixture of Iscove's Modified Dulbecco's Medium and Ham's F-12, supplemented with insulin 10$\mu\textrm{g}$/$m\ell$, transferrin 10$\mu\textrm{g}$/$m\ell$, ethanolamine 10$\mu$M and selenium 30nM (designated EBM (enriched basal medium) with the supplements). The effect of various supplements of steroid hormones, vitamins, lipid and mineral salts was investigated and their optimal concentration was determined to replace fetal calf serum (PCS). These components were added respectively and then added by way of two or three combination to discern of which component combination was effective to the culture of hybridoma. As a result, serum-free medium KM3 (EBM with BSA 100$\mu\textrm{g}$/$m\ell$, mineral cocktail and 0.05% PEG) was deter-mined. The hybridoma Alps 25-3 cultured in this medium showed almost the same growth rate as in medium added with 2% fetal bovine serum. However, the antibody concentration from KM3 cultures was 80% of that obtained from culture with FCS. KM3 was also examined for the culture of other mouse hybridomas, KW, A4W & HCGK, and it was confirmed that it could support the growth of these hybridomas and the production of monoclonal antibodies.

• Journal of Astronomy and Space Sciences
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• v.28 no.2
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• pp.123-132
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• 2011

It is generally believed that the occurrence of a magnetic storm depends upon the solar wind conditions, particularly the southward interplanetary magnetic field (IMF) component. To understand the relationship between solar wind parameters and magnetic storms, variations in magnetic field polarity and solar wind parameters during magnetic storms are examined. A total of 156 storms during the period of 1997~2003 are used. According to the interplanetary driver, magnetic storms are divided into three types, which are coronal mass ejection (CME)-driven storms, co-rotating interaction region (CIR)-driven storms, and complicated type storms. Complicated types were not included in this study. For this purpose, the manner in which the direction change of IMF $B_y$ and $B_z$ components (in geocentric solar magnetospheric coordinate system coordinate) during the main phase is related with the development of the storm is examined. The time-integrated solar wind parameters are compared with the time-integrated disturbance storm time (Dst) index during the main phase of each magnetic storm. The time lag with the storm size is also investigated. Some results are worth noting: CME-driven storms, under steady conditions of $B_z$ < 0, represent more than half of the storms in number. That is, it is found that the average number of storms for negative sign of IMF $B_z$ (T1~T4) is high, at 56.4%, 53.0%, and 63.7% in each storm category, respectively. However, for the CIR-driven storms, the percentage of moderate storms is only 29.2%, while the number of intense storms is more than half (60.0%) under the $B_z$ < 0 condition. It is found that the correlation is highest between the time-integrated IMF $B_z$ and the time-integrated Dst index for the CME-driven storms. On the other hand, for the CIR-driven storms, a high correlation is found, with the correlation coefficient being 0.93, between time-integrated Dst index and time-integrated solar wind speed, while a low correlation, 0.51, is found between timeintegrated $B_z$ and time-integrated Dst index. The relationship between storm size and time lag in terms of hours from $B_z$ minimum to Dst minimum values is investigated. For the CME-driven storms, time lag of 26% of moderate storms is one hour, whereas time lag of 33% of moderate storms is two hours for the CIR-driven storms. The average values of solar wind parameters for the CME and CIR-driven storms are also examined. The average values of ${\mid}Dst_{min}{\mid}$ and ${\mid}B_{zmin}{\mid}$ for the CME-driven storms are higher than those of CIR-driven storms, while the average value of temperature is lower.

• Journal of the Korean Society of Food Culture
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• v.20 no.4
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• pp.451-458
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• 2005

For the storaging and frying stability in soybean oil, the kind of treating antioxidants were mixed tocopherol and phosphatidyl choline(PC), phosphatidyl ethanolamine(PE), phosphatidyl inpsitol(PI), phosphatidyl serine(PS), phosphatidic acid(PA), phosphatidyl glycerol(PG), treating amounts were 0.03%, 0.05%(w/w), respectively. Acid value(AV), peroxide value(POV) and oxidative stability index(OSI) were determined during storage period at $50^{\circ}C$ in soybean oil. Antioxidation effect at frying condition was determined through changes of smoke point. The antioxidation effect according to AV change was $PA>PC>PI{\geq}PG>PS{\geq}PE$, preventing effect about POV change was PA>PG>PC>PS>PE>PI and preventing effect about OSI decreasing was PI>PC>PA>PG>PS>PE. At the result, antioxidation effect of individual phospholipid components in soybean oil was appeared different result according to determination code. Determination result of preventing effect of SP decreasing according to frying at $180^{\circ}C$ during 20 hours was PA>PC>PG>PE>PI>PS. But treating effect of mixed tocopherol in preventing effect about AV, POV was not. In the case of storage at $50^{\circ}C$ in soybean oil, mixed tocopherol was affected as a kind of pro-oxidant. In OSI had some antioxidation effect, preventing effect of SP decreasing had not. Treatment of mixed tocopherol in soybean oil was undesirable as frying oil.

• Journal of the Korean Institute of Gas
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• v.22 no.2
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• pp.46-51
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• 2018

Hydrogen sulfide from landfill and sewage treatment plant is a major odor component and causes many civil petitions. Rapidly developing industries release hydrogen sulfide, an odorous gas, to the atmosphere. This study aims to develop a $10{\mu}mol/mol$ concentration level hydrogen sulfide primary standard gas for odor measurement. The hydrogen sulfide gas was prepared at a nominal concentration of $10{\mu}mol/mol$ in nitrogen using the gravimetric method described in ISO 6142. Replicate standard gases were produced in 4 aluminium cylinders, and their concentrations were verified by GC-AED. The uncertainty of production was less than 0.50 %, and the variation of the 4 replicates was 0.22 %. The wall adsorption of hydrogen sulfide in cylinders was 0.10 % at 1500 psi, and the concentration was estimated to be long-term stable for one year. The relative expanded uncertainty of the preparation consistency, adsorption and long-term stability of this hydrogen sulfide standard gas was less than 1.05 % (95 % of confidence level, k=2).

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.11 no.3
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• pp.290-294
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• 2018

Modern warfare exhibit a NCW (Network Centric Warfare) aspect through quick situation awareness and Command and Control. And Tactical messages operate on various tactical data links (TDLs). For monitoring TDL messages processed by data link processor(DLP), message analysers are generally developed as a component during system development. In addition, in order to forward TDL messages processed by DLP to the message anayzer, the interface messages between DLP and message analysers should be defined interface control document(ICD). We propose the methods using UDP or TCP packets provided by TDL layers that are delivered to DLP without communicating directly with DLP. Depending on TDL message standards and Interface Control Documents(ICDs), we design the message analyzer which communicates with data link processor using internal messages. Using known header field information from the TDL application standard such as JREAP-C, we can quickly filter candidate packets against collected packets and use the full data size information contained in the headers to verify the completed message. Because the methods proposed in this paper do not communicate directly with DLP, the methods proposed in this paper are enable to analyze the TDL application messages such as JREAP-C or Link-K without constraints in existing methods that should be reflected in the system configuration and ICD.