• Economic and Environmental Geology
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• v.56 no.6
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• pp.745-764
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• 2023

In the Republic of Congo, Banded iron formations (BIFs) occur in two areas: the Chaillu Massif and the Ivindo Basement Complex, which are segments of the Archean Congo craton outcropping in the northwestern and southwestern parts of the country. They show interesting potential with significant mineral resources reaching 2 Bt and grades up to 60% Fe. BIFs consist mostly of oxide-rich facies (hematite/magnetite), but carbonate-rich facies are also highlighted. They are found across the country within the similar geological sequences composed of amphibolites, gneisses and greenschists. The Post-Archean Australian Shale (PAAS)-normalized patterns of BIFs show enrichment in elements such as SiO₂, Fe₂O₃, CaO, P₂O₅, Cr, Cu, Zn, Nb, Hf, U and depletion in TiO₂, Al₂O₃, MgO, Na₂O, K₂O, Sc, Th, Ba, Zr, Rb, Ni, V. REE diagrams show slight light REEs (rare earth elements; LREEs) compared to heavy REEs (HREEs), and positive La and Eu anomalies. The lithological associations, as well as the very high (Eu/Eu^*)_SN ratios> 1.8 shown by the BIFs, suggest that they are related to Algoma-type BIFs. The positive correlations between Zr and TiO₂, Al₂O₃, Hf suggest that the contamination comes mainly from felsic rocks, while the absence of correlations between MgO and Cr, Ni argues for negligeable contributions from mafic sources. Pr/Pr^* vs. Ce/Ce^* diagram indicates that the Congolese BIFs were formed in basins with redox heterogeneity, which varies from suboxic to anoxic and from oxic to anoxic conditions. They were formed through hydrothermal vents in the seawater, with relatively low proportions of detrital inputs derived from igneous sources through continental weathering. Some Congolese BIFs show high contents in Cr, Ni and Cu, which suggest that iron (Fe) and silicon (Si) have been leached through hydrothermal processes associated with submarine volcanism. We discussed their tectonic setting and depositional environment and proposed that they were deposited in extensional back-arc basins, which also recorded hydrothermal vent fluids.

• Journal of Sasang Constitutional Medicine
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• v.7 no.2
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• pp.183-212
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• 1995

In order to investigate the influence of four Sasang prescriptions, $So{\breve{u}}min$ P'almunjat'ang(SPG), $So{\breve{u}}min$ Sltibimikwanjungt'ang(SSK), $T^{\prime}ae{\breve{u}}min$ $Chowis{\breve{u}}ngch^{\prime}{\breve{o}}ngt^{\prime}ang$(TCS), and $T^{\prime}ae{\breve{u}}min$ $Ch^{\prime}{\breve{o}}ngp^{\prime}yesagant^{\prime}ang$(TCP), on the activity of the autonomic nervous system in the rats exposed to noise and vibration stress, the contents of catecholamines in the urine, body temperature, heart rate, blood pressure, and stomach mucosa change were checked in this experiment. The results obtained were as follows; 1. On the 7th and 12th days from the beginning, the experimental indexes of the controled group were increased more than those of the normal group, and it meant that the noise and vibration stress induced an autonomic nervous system disorder in rats. 2. The urine-epinephrine contents in all experimental groups were decreased more than in the controled group, and in the Tcs and the Tcp groups those were significantly decreased on the 7th and 12th days. 3. The urine-norepinephrine contents in the SPK, TCS, and the TCP groups were significantly decreased on the 7th day, and in the TCS and the SPG groupsthose were significantly decredsed on the 12th day. 4. The urine-dopamine contents in the TCS group were significantlly decreased on the 12th day. 5. The body temperaature was decreased significantly in the SPG and the SSK groups on the 7th day. 6. The heart rate was significantly decreased in the SPG group on the 7th day, and it was decreased significantly in the SPG and the SSK groups on the 12th day. 7. The blood pressure was decreased in ghe SPG group significantly on the 7th day. 8. The stomach mucosa remarkably recovered from gastric ulcers in the SPG group and significantly recorvered in the other groups on the 7th day. From the above findings, th could be assumed that Taeumin and Soumin prescriptions had some significant influence on the control of the autonomic nervous system in the rats that recieved stress.

• Journal of Bio-Environment Control
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• v.8 no.3
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• pp.172-182
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• 1999

Leaf lettuce(Lacaug sativa L.) was cultivated in deep flow culture to investigate growth and yield in relation to different reusing method of nutrient solution after once cultivation. Five different treatments were allocated to the nutrient solutions - Control(total renewal of solution), NSS(nutrient solution supplement), U control, NSAC(nutrient solution analysis and compensation), NSAC and Humus supply(NSAC with supply of Humus). The pH of solution was kept stable below 7.0 during 4 successive culture in NSAC and NSAC and Humus supply. U was sharply declined in NSS as the number of cultivation was increased. Gmwth and yield of NSAC was similar to those of Control because nutrient elements were kept the balance to the better growth, while the lettuce grown in NSS and EC control was shown lower growth rate. In the nutrient solutions, Content of N $O_3$-N and N $H_4$-N were remarkably decreased after the cultivation in all treatments. Ca and Mg were shown to be accumulated in nutrient solution regardless of culture times and treatments. After the first culture in NSAC and Humus supply, total N and P$_2$ $O_{5}$ content in leaves were lower than any other treatments, but Ca content was higher. Those were not significant as following cultures, and no significant difference of K and Mg content were shown among the treatments.

• Journal of the Korean Chemical Society
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• v.6 no.1
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• pp.1-9
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• 1962

Bench-scale horizontal cation-permeable membrane cells were constructed to study the effect of cell dimensions on the efficiency of electrolytic reduction of uranyl sulphate solutions flowing continuously over a mercury cathode. Current efficiencies were determined for various cells having length-to-width ratios of 10/1 to 40/1, and for catholyte solutions containing from 20 to 100g $U_3O_8/l$ in sulphuric acid. Optimum current density and solution flowrate were determined under these conditions. The effects of the nitrate and chloride ions were briefly examined.

• Maritime Security
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• v.1 no.1
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• pp.215-240
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• 2020

In 2017, the U.S. DARPA coined 'mosaic warfare' as a new way of warfighting. According to the Timothy Grayson, director of DARPA's Strategic Technologies Office, mosaic warfare is a "system of system" approach to warfghting designed around compatible "tiles" of capabilities, rather than uniquely shaped "puzzle pieces" that must be fitted into a specific slot in a battle plan in order for it to work. Prior to cover mosaic warfare theory and recent development, it deals analyze its background and several premises for better understanding. The U.S. DoD officials might acknowledge the current its forces vulnerability to the China's A2/AD assets. Furthermore, the U.S. seeks to complete military superiority even in other nation's territorial domains including sea and air. Given its rapid combat restoration capability and less manpower casualty, the U.S. would be able to ready to endure war of attrition that requires massive resources. The core concept of mosaic warfare is a "decision centric warfare". To embody this idea, it create adaptability for U.S. forces and complexity or uncertainty for the enemy through the rapid composition and recomposition of a more disag g reg ated U.S. military force using human command and machine control. This allows providing more options to friendly forces and collapse adversary's OODA loop eventually. Adaptable kill web, composable force packages, A.I., and context-centric C3 architecture are crucial elements to implement and carry out mosaic warfare. Recently, CSBA showed an compelling assessment of mosaic warfare simulation. In this wargame, there was a significant differences between traditional and mosaic teams. Mosaic team was able to mount more simultaneous actions, creating additional complexity to adversaries and overwhelming their decision-making with less friendly force's human casualty. It increase the speed of the U.S. force's decision-making, enabling commanders to better employ tempo. Consequently, this article finds out and suggests implications for Korea armed forces. First of all, it needs to examine and develop 'mosaic warfare' in terms of our security circumstance. In response to future warfare, reviewing overall force structure and architecture is required which is able to compose force element regardless domain. In regards to insufficient defense resources and budget, "choice" and "concentration" are also essential. It needs to have eyes on the neighboring countries' development of future war concept carefully.

• Advances in Traditional Medicine
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• v.8 no.3
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• pp.302-310
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• 2008

Azadirachta indica A. Juss (N.O. Meliaceae), popularly known, as 'Neem' is an indigenous tree widely available in India. Almost every part of the tree has long been used in Unani system of medicine for the treatment of a variety of human ailments. The flowers have been mentioned as a remedy useful in controlling diabetes mellitus. The present study had been designed to investigate the hypoglycemic/anti-hyperglycemic effects of the methanolic extract of the flowers of A. indica (Gule-Neem) and its different fractions on normal, glucose fed hyperglycemic, adrenaline induced hyperglycemic and alloxan induced diabetic rats. The methanolic extract was resolved into water soluble and water insoluble fractions. Water soluble portion of the methanolic extract was found to possess significant blood sugar lowering effect in glucose-fed and adrenaline-induced hyperglycemic rats but it did not show such effect in normal and alloxan induced mild and severe diabetic rats. Water-soluble portion was fractionated by employing the polarity criterion with ethyl acetate and butanol. The ethyl acetate fraction was further fractionated into phenolic and non-phenolic fractions. Hypoglycemic effect of these fractions was also evaluated. The results suggest that the flowers of A. indica contain at least two different constituents, responsible for the said activity. These investigations validate the use of flowers of A. indica in diabetes by Unani physicians.

• Journal of Sasang Constitutional Medicine
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• v.7 no.2
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• pp.227-240
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• 1995

In order to, study the anti-stress effect of $Tae{\breve{u}}min$ $Ch{\breve{o}}ngsimy{\breve{o}}njat^{\prime}ang$, several measures of stress, including catecholmine changes, body weight changes, and gastric ulcers were used.the following result were observed: 1. Plasma epinephrine contents of stress by food in rats, in the controlled group were $219.3{\pm}18.4pg/ml$, but in the experimental group the value was decreased to $169.0{\pm}16.6pg/ml$. 2. Plasma norepinephrine content of stress by food in rats in the controlled group was $303.0{\pm}18.9pg/ml$ but in the experimental group the value was decreased to $243.6{\pm}17.6pg/ml$. 3. Plasma dopamine contents of stress by food in rats in the controlled group was $16.9{\pm}1.9pg/ml$ but in the experimental group the value was derceased to $12.8{\pm}1.5pg/ml$, but it was nonsignificant. 4. Effects of body weight of stress by food in the Shay rats in controlled group was $175.9{\pm}3.0g$, but in the experimental grou the value was increased to $187.7{\pm}4.8g$. 5. Gastric ulcers of stress by food in Shay Rats, in the experimental group, the glade was decreased more than in the control group. 6. It is considered that the anti-stress effect of Taeumin Chongsimyonjat' depends on its concentration rate. Based on the results above, it may be concluded that Taeumin chongsimyonjat' aug is effective to prevent the harmful effects of stress.

• The Bulletin of The Korean Astronomical Society
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• v.35 no.1
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• pp.45.1-45.1
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• 2010

한국천문연구원과 일본 국립천문대는 공동으로 한일공동VLBI상관기(Korea-Japan VLBI Correlator, KJJVC)를 개발하였다. 이 상관기는 최대 16 관측국에 대하여 16 세트의 자기상관 및 120 세트의 상호상관을 계산할 수 있다. 각 관측국당 최대 8,192 Mbits/sec의 입력 데이터를 처리할 수 있으며, 8,192개의 주파수채널을 갖는 상관 스펙트럼을 약 25.4 밀리초~수초의 적분 시간으로 출력할 수 있는데, 최대 상관 출력 속도는 1.4GB/sec이다. 한편, 이 상관기는 한국우주전파관측망(KVN) 뿐만 아니라 동아시아VLBI관측망 및 우주공간VLBI관측망의 관측 데이터도 처리할 수 있도록 설계 제작되었으며, 최대 지연 추적 범위는 ${\pm}35,000km$이며, 보상 가능한 최대 기선 속도는 7.5km/sec이다. 현재 다른 VLBI관측망에서 사용하고 있는 타 상관기의 경우 지연은 2차 미분까지 보상하고, 프린지 위상은 3 단계로 보상하고 있는 것에 비하여, 한일공동VLBI상관기에서는 지연은 3차 미분까지 보상하여 지연 잔차를 최소화하고 프린지 위상은 16 단계로 세분하여 보상 수준의 정밀도를 최대화하였다. 이러한 지연 보상 및 프린지 멈춤 알고리즘을 상세히 소개하고 그 특성 및 장점을 보고한다.

• Journal of Embryo Transfer
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• v.21 no.2
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• pp.101-107
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• 2006

The objective of this study was to investigative the effects of retinol supplement to IVM and/or IVC medium on maturation, fertilization and development of pig oocytes. North Carolina State University (NCSU) 23 medium containing porcine follicular fluid (pFF) was used as base medium. Each 1 uM, 5 uM and 10 uM concentration of retinol was supplemented to IVM and /or IVC medium. When the retinol was supplemented to maturation medium, the maturation rates were not different (p>0.05) among treatment groups ($66.7{\pm}6.0{\sim}69.2{\pm}5.3%$), but the developmental rate to blastocyst stage was higher (p<0.05) in $5{\mu}M$ group ($20.4{\pm}2.6%$) than in 0 uM ($13.6{\pm}2.1%$) and 10 uM groups ($9.7{\pm}1.7%$). Moreover, total cell number was significantly greater (p<0.05) in the 5 uM group ($37.0{\pm}1.6$) than in the other groups ($29.8{\pm}1.0{\sim}33.2{\pm}1.0$). Retinol supplement to maturation medium did not significantly affect the rates of fertilization and polyspermy (p>0.05). When the retinol was supplemented to culture medium or both maturation and culture medium, the rates of cleavage, and develop to morula and blastocyst stage were not affected, while those of 10 uM group were significantly decreased (p<0.05). These results indicate that 5 uM retinol supplement in maturation medium significantly stimulates embryo development, also improves the total cell number of blastocyst stage in pig.

• Journal of Ecology and Environment
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• v.39 no.1
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• pp.43-49
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• 2016

Fishways are constructed to provide longitudinal connectivity of streams or rivers where their flow has been altered by in-stream structures such as dams or weirs. Nature-like fishways have an additional function of providing fish habitats. In the study, we estimated the role of a nature-like fishway (length: 700 m, slope: 1/100) for fish habitat by using two dominant species in the Sangju Weir, Nakdong River, to calculate the optimal ecological flow rate using Physical HABitat SIMulation (PHABSIM). To identify the dominant species that used the fishway, we conducted trap monitoring from August to November 2012 at the fishway exit. The dominant species were Zacco platypus and Opsariichthys uncirostric amurensis with a relative abundance of 62.1% and 35.9%, respectively. Optimal habitat suitability indices (HSIs) for Z. platypus and O. u. amurensis were calculated as 0.6-0.8 m/s (water velocity) and 0.2-0.4 m (water depth), and 0.5-0.7 m/s (water velocity) and 0.1-0.3 m (water depth), respectively. The optimal ecological flow rates (OEFs) for Z. platypus and O. u. amurensis were 1.6 and 1.7 cubic meter per second (CMS), respectively. The results of the study can be used in a management plan to increase the habitat function of nature-like fishways in the Sangju Weir. This methodology can be utilized as an appropriate tool that can determine the habitat function of all nature-like fishways.