• Economic and Environmental Geology
• /
• v.43 no.1
• /
• pp.21-31
• /
• 2010

Mine and leachate waters were collected from the Okdong mine for study on reaction with oxidizing agents such as NaOCl and $H_2O_2$. The pH and EC of the mine and leachate waters are 5.77, 831 uS/cm, and 6.38, 1920 uS/cm, respectively. The concentrations of Mg, Mn, and Zn are 23.25 mg/l, 14.90 mg/l, and 22.99 mg/l for the mine water and 98.75 mg/l, 3.38 mg/l, and 6.16 mg/l for the leachate water. The concentrations of Mg, Mn and Zn decreased after the reaction with the oxidizing agents and mine water. The concentrations of Mg, Mn and Zn rapidly decreased when oxidizing agents increased. The saturation indices that were computed by visual MINTEQ for initial mine and leachate water were undersaturated with Mg, Zn and Mn compounds. The precipitates after the reaction with the oxidizing agents are composed mainly of mangano-calcite[(Mn, Ca)$CO_3$] with small amount of calcite-magnesian and calcite.

• Economic and Environmental Geology
• /
• v.42 no.4
• /
• pp.301-314
• /
• 2009

The Taebaeksan mineralized province, which is the most important one in South Korea, is rich in zinc-lead-tungsten-iron-copper-molybdenum-silver-gold mineral resources and has a diversity of deposit styles. These deposits principally coexist in time and space with porphyry-related epigenetic deposit such as skarn, hydrothermal replacement, mesothermal vein, and Carlin-like deposits. The magmatic-hydrothermal systems in the Taebaek fold belt is genetically characterized by the Bulguksa subvolcanic rocks(ca. $110{\sim}50\;Ma$) related to northwestward subduction of the paleo-Pacific Plate. The most important zinc-lead deposits in the area are the Uljin, Yeonhwa II and Shinyemi skarn, the Janggun hydrothermal replacement, and the Yeonhwa I intermediate-mixed (skarn/hydrothermal replacement) ones. In the present study, we present a compilation of metal production and mineral assemblage of the zinc-lead deposits. The metal difference of deposit styles in the area indicates a cooling path from intermediate-sulfidation to low-sulfidation state in the polymetallic hydrothermal system, reflecting spatial proximity to a magmatic source.

• Journal of Life Science
• /
• v.15 no.3 s.70
• /
• pp.374-381
• /
• 2005

The production of functional foods providing health benefit is one of the fast growing fields in the food industry. Mannitol as GRAS (generally recognized as safe) is a functional food. Mannitol is about $70\%$ as sweet as sucrose and slowly and incompletely absorbed from the intestine, suppling only about one-half energy value of glucose. Commercially, the mannitol is synthesized by catalytic or electrochemical reduction of glucose. However, as strong demand for natural products increased, biological techniques have been developed for mannitol production. The object of this study was to determine the optimum conditions of mannitol fermentation by Leuconostoc mesenteroides sp. strain JFY isolated from fermented vegetables. The processes parameters such as pH, temperature, yeast extract concentration, and fructose concentration were optimized. The chosen ranges were 4.5 to 7.5 for pH, 22 to $34^{\circ}C$ for temperature, 0.05 to $2.0\%$ for yeast extract. and 5 to 350 g/L for fructose. The mineral medium used consisted of 3.0g $KH_2PO_4,\;0.01g\;FeSO_4{\cdot}H_2O,\;0.01g\;MnSO_4{\cdot}4H_2O,\;0.2g\; MgSO_4{\cdot}7H_2O,\;0.01g\;NaCl,\;and\;0.05g\;CaCl_2$ per 1 liter of deionized water. The optimum values of pH, temperature, yeast extract, and fructose concentration were obtained at about pH 6.5, temperature $28^{\circ}C$, yeast extract $0.5\%$ and fructose 30g/L. At optimum condition, the production of mannitol amounted to 31.6g/l. We hope that these findings are of particular importance for industrial application of mannitol production.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.27 no.2
• /
• pp.123-128
• /
• 2007

A study was conducted over two years to determine the temperate mixtures of grasses for grazing horses in Jeju, Korea. The experiment field located at 450 m altitude (Jeju Horse Training Center of Korea Racing Association) was divided into 3 different mixtures plots (3 replications) without a fence between treatments, and sown by three main grasses (orchardgrass, perennial ryegrass and timothy). Seven castrated adult horses were kept on pasture from the middle of April to the end of November without supplementary concentrates. The dry matter yield, percentage of grasses intake and botanical composition were determined during the grazing period. Nutrients in grasses and soils were analyzed. The dry matter yield during two-year experimental period was not different among mixtures (11,000-12,000 kg/ha/year). In botanical composition, perennial ryegrass was dominant in all mixtures during spring through early summer season, but faded away during hot summer season. Timothy seemed to be more resistant against a hot or dry weather than other grasses. The percentage of grasses intakes was higher in the mixture of timothy than those in other mixtures. The contents of NDF (neutral detergent fiber) and ADF (acid detergent fiber) were not different among different mixtures. These results indicate that the mixture of timothy, orchardgrass, perennial ryegrass and white clover (20, 5, 5, 2 kg/ha as a seeding rate) can be used for gazing pasture of horses in the high altitude of Jeju.

• Proceedings of the Korean Information Science Society Conference
• /
• 2006.10d
• /
• pp.24-29
• /
• 2006

본 논문에서는 광대역 통신 방송 융합 서비스 제공을 고려한 WDM 메트로 링 망을 위한 매체 접근 제어(Medium Access Control; MAC) 프로토콜의 성능을 분석한다. 현재 인터넷은 통신 방송 융합 망으로 진화하고 있으며 다양한 트래픽 특성을 갖는 서비스가 액세스 망에서 메트로 망으로 유입되고 있다. 그러나 기존 메트로 망의 MAC 프로토콜은 이러한 망 환경 변화를 고려하지 않고 단순하고 동일한 트래픽만을 고려하여 성능을 분석하였다. 따라서 본 논문에서는 메트로 링에 연결된 액세스 노드의 입력 트래픽을 Self-Similar와 Poisson 트래픽으로 분류하여 기존 MAC 프로토콜의 성능을 분석하고 평가한다. 메트로 링 망에 연결된 액세스 노드는 이 두 종류의 트래픽 중에서 하나를 망에 유입하며 채널을 공유하는 노드 수에 따라서 다양한 트래픽 환경이 고려된다. WDM 메트로 링망의 기본 MAC 프로토콜은 CSMA/CA(Carrier Sense Multiple Access with Collision Avoidance)이며, 패킷을 빈 슬롯에 전송하고 송신지에서 패킷을 제거하는 SS (Source-Stripping) 기반으로 운용된다. 본 논문에서는 SS 방식으로 생성된 빈 슬롯을 바로 패킷 전송에 이용하는 방식과 그렇지 않은 방식을 각각 1-Persistent와 non-Persistent로 분류하고 MAC 프로토콜을 분석하여 기존 방식의 장 단점을 비교한다. 또한 전송 공정성과 처리율을 같이 고려하여 적용할 수 있는 확률 기반 p-Persistent MAC 프로토콜도 분석하였으며 시뮬레이션을 통하여 각 프로토콜을 노드 처리율, 전송 지연, 패킷 손실률, 전송 공정성 관점에서 비교하고 평가한다.y 수행을 여러 서버로 분산처리하게 함으로써 성능에 대한 신뢰성을 향상 시킬 수 있는 Load Balancing System을 제안한다.할 때 가장 효과적인 라우팅 프로토콜이라고 할 수 있다.iRNA 상의 의존관계를 분석할 수 있었다.수안보 등 지역에서 나타난다 이러한 이상대 주변에는 대개 온천이 발달되어 있었거나 새로 개발되어 있는 곳이다. 온천에 이용하고 있는 시추공의 자료는 배제하였으나 온천이응으로 직접적으로 영향을 받지 않은 시추공의 자료는 사용하였다 이러한 온천 주변 지역이라 하더라도 실제는 온천의 pumping 으로 인한 대류현상으로 주변 일대의 온도를 올려놓았기 때문에 비교적 높은 지열류량 값을 보인다. 한편 한반도 남동부 일대는 이번 추가된 자료에 의해 새로운 지열류량 분포 변화가 나타났다 강원 북부 오색온천지역 부근에서 높은 지열류량 분포를 보이며 또한 우리나라 대단층 중의 하나인 양산단층과 같은 방향으로 발달한 밀양단층, 모량단층, 동래단층 등 주변부로 NNE-SSW 방향의 지열류량 이상대가 발달한다. 이것으로 볼 때 지열류량은 지질구조와 무관하지 않음을 파악할 수 있다. 특히 이러한 단층대 주변은 지열수의 순환이 깊은 심도까지 가능하므로 이러한 대류현상으로 지표부근까지 높은 지온 전달이 되어 나타나는 것으로 판단된다.의 안정된 방사성표지효율을 보였다. $^{99m}Tc$-transferrin을 이용한 감염영상을 성공적으로 얻을 수 있었으며, $^{67}Ga$-citrate 영상과 비교하여 더 빠른 시간 안에 우수한 영상을 얻을 수 있었다. 그러므로 $^{99m}Tc$-transierrin이 감염 병소의 영상진단에 사용될 수 있을 것으로 기대된

• Journal of Korean Society for Atmospheric Environment
• /
• v.22 no.5
• /
• pp.590-603
• /
• 2006

Size-and time-resolved aerosol samples were collected using an eight-stage Davis rotating unit for monitoring (DRUM) sampler from 23 March to 29 April 2001 at Gosan, Jeju Island, Korea, which is one of the super sites of Asia-Pacific Regional Aerosol Characterization Experiment(ACE-Asia). These samples were analyzed using synchrotron X-ray fluorescence for 3-hr average concentrations of 19 elements including Al, Si, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Br, Rb, and Pb. The size-resolved data sets were then analyzed using the positive matrix factorization(PMF) technique to identify possible sources and estimate their contributions to particulate matter mass. PMF analysis uses the uncertainty of the measured data to provide an optimal weighting. Twelve sources were resolved in eight size ranges($0.09{\sim}12{\mu}m$) and included continental soil, local soil, sea salt, biomass/biofuel burning, coal combustion, oil combustion, municipal incineration, nonferrous metal source, ferrous metal source, gasoline vehicle, diesel vehicle, and volcanic emission. The PMF result of size-resolved source contributions showed that natural sources represented by local soil, sea salt, continental soil, and volcanic emission contributed about 79% to the predicted primary particulate matter(PM) mass in the coarse size range ($1.15{\sim}12{\mu}m$) while anthropogenic sources such as coal combustion and biomass/biofuel burning contributed about 58% in the fine size range($0.56{\sim}2.5{\mu}m$). The diesel vehicle source contributed mostly in ultra-fine size range($0.09{\sim}0.56{\mu}m$) and was responsible for about 56% of the primary PM mass.

• Journal of Nutrition and Health
• /
• v.41 no.8
• /
• pp.786-796
• /
• 2008

This study examined the influence of the nutrient intake status, dietary habit, and academic stress of elementary school children on their academic achievement. Two-hundred and twenty-four fifth-graders in Bucheon-si, Gyeonggido were surveyed. The study included the 24 hr-recall, anthropometric measurement, assessment of stress level and academic achievement. The subjects were normal in height, weight and Rohrer index, but higher percentage of underweight was seen in girls and vice versa in boys. The overall nutrient intake and dietary habits were fairly good, but Ca and folate intake was less than 75% KDRIs and dietary habits of boys were inferior. Academic stress level of all the subjects was not high. In terms of academic performance and its relations with nutrient intake, the more the amount of nutrient intake, the higher the academic performance. Especially, it was true for the energy, protein, phosphorus, potassium, zinc, polyunsaturated fatty acids, and n-6 fatty acid intakes (p < 0.05). The overall academic performance was higher for those who eating-out less frequently. Children with higher comprehensive dietary habit scores have shown better academic performance (p < 0.05). Less stress implied to those shown higher academic achievement while those with relatively poor academic performance showed high stress level since their grade did not improve as much as they anticipated. In conclusion, the academic achievement was higher for those who have a better nutritional status, better dietary habits, and lower stress levels. Therefore, it is critical for nutritionists, parents, and teachers to improve the nutritional status and dietary habits as well as to help them manage their stress levels, which will eventually contribute to an enhanced academic performance.

• Economic and Environmental Geology
• /
• v.35 no.1
• /
• pp.75-95
• /
• 2002

The Andong pluton in the Andong Batholith is composed of comagmatic plutonic rocks, in which the lithofacies comprise hornblende biotite tonalite in the central paft biotite granodiorite in the marginal paft and porphyritic biotite granite at the topside (noJthea~tern paft) of the pluton. The pluton is petrographically and petrochemically zoned, having more mafic center than margin and topside. Distribution pallern of the lithofacies represents a reverse zoning in the pluton. Modal and chemical data in the pluton show progressive and gradual compositional variations from the centrer via the margin to the topside. Quartz and K-teldspar increase toward the topside of the pluton, whereas hornblende, biotite and color index increase toward the center. The bulk composition in the pluton is also reversely zoned, with high $Si0_2$ and $K_{2}O$ in the topside facies, and high MnO, CaO, $Ti0_2$, $Fe_{2}O_{3}$t, MgO and $P_{2}O_{5}$ in the central facies. The reverse zoning is also evident in higher Cr. V, Ni, Sc and Sr of the more mafic tonalite in the interior. The reversely zoned pluton results from remobilization (resurgence) of the lower more mafic compositional zone into the upper more felsic zones of the pluton modified by thennogravitational diffusion and fractional crystallization. In the initial stages of evolution, the pluton was a petrochemical system that fonned chemical compositional zonation with mafic tonalitic magma in the lower. granodioritic one in the middle and granitic one in the upper paft of the magma chamber. Periodic influxes of more mafic magma from the ba~e resulted in mingling of liquids and redistribution of minerals, and may have triggered the remobilil.ation of the lower compositional zone into the upper more felsic zones.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.8 no.6
• /
• pp.59-68
• /
• 2005

This study was carried out to investigate soil properties, ordination, and vegetation of the coastal sand dune in Sinduri, Taean-Gun. 1. The Orobanche coerulescens and Ixeris repens that are a peculiar species were found in Sinduri coastal sand dune and the Salix purpurea var. japonica that is an endemic species of korea was found in that place. The plant communities was categorized into seven groups, such as Rosa rugosa community, Vitex rotundifolia communit, Carex kobomugi community, Imperata cylndrica var. koenigii community, Carex pumila community, Artemisia capillaris community, and Calamagrostis epigeios community. 2. The soil organic matter, total nitrogen, available phosphorous concentrations, and cation exchange capacity were lower in the study sites than in forest soil of seashore. There was little difference in soil exchangeable Ca, Mg, and K concentrations between in the study site and in the forest soil of seashore. The soil pH was ranged from 5.69 to 7.63. The soil texture in the study site was sand or loamy sand. 3. The results of the correlation between Sinduri coastal sand dune community and environmental factor are as follows; the soil pH was the most effect to the community distribution, and CEC, total nitrogen, soil organic matter, and the amount of silt in soil have some correlation with community distribution. 4. The results of the correlation between Sinduri coastal sand dune community and soil characteristics are as follows; the Calamagrostis epigeios community was found in area that have high soil moisture content; the Rosa rugosa community was found in area that have high soil CEC, organic matter concentration, and total nitrogen concentration, and low soil pH; the Vitex rotundifolia community, Carex kobomugi community, and Artemisia capillaris community were found in area that have low soil CEC, organic matter concentration, and total nitrogen concentration, and high soil pH; the Imperata cylndrica var. koenigii community and Carex pumila community were found in area that have medium soil CEC, organic matter concentration, total nitrogen concentration, and soil pH.

• Korean Journal of Food Science and Technology
• /
• v.43 no.4
• /
• pp.458-463
• /
• 2011

Recent studies have revealed that collagen peptide (CP) plays a protective role in skin by improving the activity of antioxidants and acts as an inducer of skin regeneration by positive feedback. In this study, we focused on the beneficial effect of reinforcing the CP skin barrier. To evaluate the skin barrier, hairless mice were exposed to UVB irradiation and acetone-treatment, with or without oral administration of CP. The effects on skin appearance, trans-epidermal water loss, epidermal thickness, and cytokine content were measured using bioengineering and histochemical methods. In the CP treated group, the skin had better appearance and less damage than that of the control. Furthermore, in HaCaT cells, the amount of serinepalmytoyl transferase (SPT) mRNA increased by about 1.6-fold after treatment (CP, 100 mg/L), reflecting that CP can induce SPT expression and reinforce the recovery of skin barrier function. These results suggest that CP is not only an anti-wrinkling agent but also a potent candidate as an epidermal moisturizer.