• Journal of the Korean earth science society
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• v.36 no.6
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• pp.512-519
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• 2015

Although Quaternary marine terraces and onshore paleo-shoreline records provide clues to our understanding for the mode and nature of neotectonics in the Korean peninsula, it cannot be accomplished without knowledge on both independent information of the past sea level records and tectonic deformation field together with precise results of numerical dating for higher terraces. This study reported cosmogenic radionuclides ($^{10}Be$) dating results conducted in higher terraces in the eastern and western coasts of the Korean peninsula. As a result, the measured concentration ratio of $^9Be/^{10}Be$ and the exposure ages were much younger than expected. It implies that either there is possibility of error in experimental processes or the samples experienced a complex exposure history probably included a burial at some stage. Considering the past climatic conditions around the Korean peninsula and a possible complex exposure history after the emergence of marine terrace, the discovery of a suitable study area and a sampling site are an essential part of successful $^{10}Be$ dating technique.

• Journal of Korean society of Dental Hygiene
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• v.16 no.2
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• pp.233-240
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• 2016

Objectives: The aim of this study was to evaluate the oral health status and behavior in Korean diabetic adults. Methods: The study subjects were 11,840 adults who participated in the fifth Korea National Health and Nutrition Examination Survey(2010-2012). Diabetic status was defined by doctors and fasting blood sugar(FBS) level. Oral health status was assessed by decayed-missing-filled teeth(DMFT), community periodontal index(CPI), periodontal disease, denture needs, limitation of oral function, and chewing difficulty. The oral health behavior was evaluated by oral examination within a year, brushing times a day, and use of auxiliary oral product. The data were analyzed by descriptive analysis, chi-square tests and multiple logistic regression analyses. Results: The prevalence rate of diabetes mellitus diagnosed by doctor and FBS was 8.3% and 10.2%, respectively. The prevalence rate of periodontitis was 25.4%. The proportions of $DMFT{\geq}20$, $CPI{\geq}3$, periodontal disease, denture needs, oral function limitation and chewing difficulty in the confirmed diabetic group by doctor were significantly higher than those of the non-diabetic group(p<0.05). In multiple logistic regression analysis, the adjusted odds ratio(aOR) for periodontal disease(aOR=1.73, 95% CI=1.41-2.12), presence of denture needs(aOR=1.40, 95% CI=1.06-1.84), limited oral function(aOR=1.43, 95% CI=1.15-1.78) and chewing difficulty(aOR=1.41 95% CI=1.13-1.77) in diabetic subjects were significantly higher than those of the non-diabetic subjects. There were similar associations between diabetes defined with FBS and oral health. In oral health behavior, diabetic subjects had significantly lower odds ratios for oral examination(aOR=0.76, 95% CI=0.60-0.98), brushing time ${\geq}2$ times(aOR=0.73, 95% CI=0.57-0.93), and auxiliary oral products(aOR=0.74, 95% CI=0.59-0.94). Conclusions: There was a significant relationship between oral health status and behavior in Korean diabetic adults. Further study is needed to evaluate the underlying mechanisms between diabetes mellitus and oral health status.

• Journal of the Korean School Mathematics Society
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• v.16 no.4
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• pp.771-796
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• 2013

The purpose of the study is to analyze the phenomenon of private education and to get the countermeasures of it. To do this, we approached the phenomenon of private education from the game theory, which is famous in economics. As result, we could make the mathematical model. One is a model consisted of two-person. This is a mathematical model simplifying the competition within the school. The problem of private education can be solved by the disconnection with private education and exam of school in this model. The other is a model consisted of three-person. This is a mathematical model simplifying the interscholastic competition. The problem of private education can not only be solved by the disconnection with private education and exam of school, but can be also solved by the specificity of school education in this model. We will hope that our study can give an aid in deciding an educational policy.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.1
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• pp.76-83
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• 1985

A hypothesis that artificial reforming of corn canopy could improve solar light penetration and dry matter production was tested in corn fields (var. Suwon 19) with three planting densities; low (60 ${\times}$ 40cm), medium (60 ${\times}$ 24cm) and high (60 ${\times}$ 16cm). Natural canopy was found that leaf orientations were even over all azimuth but somewhat inclined toward north-south direction and leaf angle ranged 38$^{\circ}$ to 71$^{\circ}$ from horizontal surface. Reforming corn canopy included following treatments: 1) natural canopy planted in north-south rows (natural canopy), 2)east-west plane canopy planted in north-south rows (E-W canopy), 3)east-west plane canopy and upright leaves in north-south rows, 4)north-south plane canopy (N-S canopy) in east-west rows. After corn plots were installed with training system by supporting poles and connecting wires, corn leaves were induced to a reforming direction and tied on wire. Average light intensity at the mid-point of plant height showed 5-10% increases in E-W canopy and in E-W canopy plus upright leaves, but a 2-10% decrease in N-S canopy from natural canopy. At yellow ripe stage, total dry wt. was increased in E-W canopy but not in N-S canopy. The E-W canopy produced 3-10% more grain yield than natural canopy. Though E-W canopy plus upright leaves yielded less at low density, it yielded up to 10% more at higher density. The N-S canopy yielded similar to low compared with natural canopy. These results suggests that reforming canopy toward solar incident direction increases light penetration into lower canopy, photosynthetic efficiency and grain yield, especially at high planting density in corn.

• Korean Journal of Food Science and Technology
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• v.20 no.4
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• pp.504-510
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• 1988

The physicochemical properties of rice flours which were obtained by dry milling(blade, hammer, test and micro mill) and wet & dry milling (roller & micro mill) were investigated. The resulting flour particle sizes were reduced in the order that of blade, hammer, test, micro and roller & micro mill. Scanning electron microscopic examination showed that the starch granules were freed from the imbedding matrix as the particles became finer. The test-milled flour had the hightest levels of starch damage, maltose value and hot-water soluble amylose content, and the blade-milled flour showed the lowest levels. Amylograph viscosity and gelatinization temperature of the flours decreased as the particles became finer, and the addition of $Hg^{+2}$ increased the peak viscosity of the dry-milled flour pastes, whereas the wet & dry-milled flour did not show any changes. The blue values and ${\lambda}$max values of the iodine complex of the cold-water extractable ${\alpha}-D-glucan$ from flours were in the range of 0.023-0.029 and 518-522nm, respectively, indicating these materials were shown to be mainly composed of amylopectin-like polymer.

• Magazine of the Korean Society of Agricultural Engineers
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• v.39 no.1
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• pp.75-82
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• 1997

건설기술과 산업의 발전에 따라 구조물은 대형화되어 가고, 건설공사의 급격한 팽창으로 골재 수용량이 급증함에 따라 천연골재자원은 점차 부족현상을 면치 못할 처지에 있다. 또한, 무리한 천연골재의 채취는 자연환경을 훼손시킬 뿐만 아니라 자연보호 측면에서도 심각한 공해문제로 대두되고 있어 공급량 부족현상은 날로 심화되고 있다. 이에 세계 몇몇 나라에세는 산업부산물을 이용한 골재 생산으로 공해예방과 폐기물 활용방법을 연구하고 있다. 산업부산물중 플라이 애쉬 생산량은 전 세계적으로 매년 약 2억여톤에 달하고 있으나 이중 일부만 활용되고 있는 실정이다. 이와같은 부산물을 활용하기 위한 일환으로 산업부산물인 PFA(Pulverized Fuel Ash)로 만든 인공경량골재의 년생산량이 영국은 600,000$m^3$, 미국은 300,000$m^3$이며, 매년 증가주세에 있다. 고성능 경량골재 콘크리트는 단위중량의 증가없이 내구성과 강도를 향상시켜 실용화 측면에서 경제적인 효과가 있으며, 플라이 애쉬로 만든 경량골재는 시멘트와의 친화력이나 접착면에서 우수한 것으로 알려져 있다. 본 시험에 사용한 골재는 플라이 애쉬로 만든 인공경량 조골재와 강모래이고, 결합제로서 프틀랜드 시멘트를 사용하였다. 부수적인 결합재로서는 플라이 애쉬, 슬래그, 실리카 흄을 사용하였으며, 고성능 경량골재 콘크리트를 개발코자 재령 28일과 180일의 압축강도가 각각 50MPa와 60MPa가 되도록 배합설계를 하였다. 본 연구에서는 플라이 애쉬, 슬래그, 시리카 흄과 같은 산업부산물을 혼입했을때 경량골재 콘크리트의 압축강도, 휨강도, 동탄성계수, 공극체적, 공극률, 단위중량, 공극 크기별 분포등의 변화를 실험적으로 구명하여 재반 구조용 콘크리트에 활용하기 위한 기초자료를 마련코저 한다.있어 특정한 발육단계의 난포 사망기전을 연구하기 어렵다. 또한 난포는 생체 내에서 다양한 호르몬을 동시에 분비하기 때문에 특정한 난소국부호르몬이 사망기전에 미치는 영향을 조사하기 힘든 점이 있다. 최근 들어 난포체외배양이 다양하게 개발되면서, 이러한 어려운 점을 극복할 수 있게 되었다. 본 논문은 각 발육단계의 난포를 절단해 체외배양하면서, apoptosis DNA 절단 현상을 이용하여 각종 난소국부 호르몬들이 난포발육단계별로 사망기전에 미치는 영향을 요약해 보였다. 난포는 발육하면서 점차 복잡한 호르몬 경로를 생존을 위해 필요로 한다. Prevulatory난포생존에 필요한 난소국부호르몬들은 early antral 단계의 난포에서는 그 미치는 영향이 감소되다가 preantral단계의 난포에서는 영향을 전혀 미치지 못했다. 단지 예외는 cGMP처리로써, 세포내 cGMP수준을 일정하게 유지시켜주는 것이 난포발육단계에 무관하게 생존에 중요한 인자로, 장래 연구는 난포 세포내의 cGMP수준을 조절하는 기작을 규명하는데 있을 것이다.인정되지 않았다. 7. 농지보전 처리구인 배수구와 초생수로구는 비처리구에 비해 낮은 침두 유출량과 낮은 토양유실량을 나타내었다.구보다 14% 절감되는 것으로 나타났다.작용하는 것으로 사료된다.된다.정량 분석한 결과이다. 시편의 조성은 33.6 at% U, 66.4 at% O의 결과를 얻었다. 산화물 핵연료의 표면 관찰 및 정량 분석 시험시 시편 표면을 전도성 물질로 증착시키지 않고, Silver Paint 에 시편을 접착하는 방법으로도 만족한 시험 결과를 얻을 수 있었다.째, 회복기 중에 일어나는 입자들의 유입은 자기폭풍의 지속시간을 연장시키는 경향을 보이며 큰 자기폭풍일수록 현저했다. 주상에서 관측된 이러한 특성은 서브스톰 확장기 활동이 자기폭풍의 발달과 밀접한 관계가

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.10
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• pp.1322-1328
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• 2006

In our previous study, a novel herb mixture (HIM-I) of Angelica gigas radix, Cnidium officinale rhizoma, and Paeonia japonica radix was developed to protect= the intestinal and immune systems and to promote their recovery from radiation damage. A new herbal composition (HemoHIM) with the high immune modulating activity was developed from HIM-I. In the present study, we examined the effects of HemoHIM on the maturation process of murine bone marrow (BM)-derived dendritic cells (DC). BM cells were cultured in the presence of iL-4 and GM-CSF and the generated immature DC were stimulated with HemoHIM for 24 hours. HemoHIM significantly enhanced the expression of co-stimulatory molecules, CD80 and CD86, especially. The activation capacity of HemoHIM-treated DC was significantly higher than that of immature DC, as analyzed by IL-2 and $IFN-\gamma$ production and proliferation of the responding T cells in the co-culture with allogeneic T cells. The antigen-presenting capacity of HemoHIN-treated DC was also increased by the co-culture with OVA-specific T cells (HS-1), as analyzed by IL-2 and $IFN-\gamma$ production and the proliferation. These results indicate that HemoHIM causes the maturation and ;Activation of DC, which may be a part of mechanisms of immunomodulation by HemoHIM.

• Journal of Aquaculture
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• v.10 no.4
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• pp.417-424
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• 1997

This study was carried out to investigate the effects of experimental formulated diets, commercial diets and natural diet(dried Undaria) on growth and body composition of Haliotis discus hannai. Experimental diets was formulated to provide 34.1% protein and 7.5% lipid, and prepared by different $CaCl_2$ concentration (5, 10 and 15%) and dipping time (10, 20 and 60 second) in solution. The juvenile abalone average weighing 0.3g were distributed in a flow-through aquarium system using a cmpletely randomized desing with 13 diets and 3 replictes per diet (50 abalone/tank), and fed diets for 17 weeks. The abalone fed the time nine experimental formulated diets and two commercial diets showed better growth performance than that of natural diets. No significant differences were found among abalone fed the experimental diets and commercial diets in survival rate, weight gain, soft body weight and soft body composition (P>0.05).

• Korean Journal of Food Science and Technology
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• v.14 no.4
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• pp.364-369
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• 1982

Two varieties of potatoes, Irish cobbler and Shimabara stored for seven and nine months respectively by irradiation combined with natural low temperature (year-round temperature change:$2{\sim}17^{\circ}C)$ on a batch scale were investigated on the suitability for processing of potato chip. Nine months after storage, irradiated potatoes (Irish cobbler) tended to maintain somewhat-better texture and sensory quality than untreated in potato chip processing. Peel rate, closely related to potato chip yield, of untreated potatoes were $20{\sim}25%$ higher than those of irradiated and Agtron color determination of potato chip from both irradiated were commercially acceptable. Preservation of potatoes by irradiation combined with natural low temperature was evaluated as an alternative method of the supply for raw materials of potato chip processing in the off season in Korea.

• Journal of the Mineralogical Society of Korea
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• v.23 no.4
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• pp.377-393
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• 2010

Pumiceous tuffs occurring in the Beomgockri Group are examined applied-mineralogical characteristics and their controling factors to evaluate their potentials as the adsorption-functional mineral resources. The pumiceous tuffs are diagenetically altered to low-grade zeolitcs and bentonites in the Janggi area. Compositional specialty due to the presence of pumice fragments induces the altered tuffs to exhibit the characteristic adsorption property combined with cation exchange capacity, specific surface area, and acidic pH. Unusual lower pH in the adsorption-functional mineral substances is turned out to be originated from the presence of H-smectite having $H^+$ in the interlayer site of the sheet structure. On account of disordered crystallinity resulting from the exchanged $H^+$ in the interlayer site, the smectite commonly forms crenulated edges in the planar crystal form and exhibits characteristic X-ray diffraction patterns showing comparatively lower intensities of basal spacings including (001) peak than conventional Ca-smectite. Based on the interpretation of paragenetic relations and precursor of the H-smectite, a genetic model of the peculiar clay mineral was proposed. The smectite formation may be facilitated resulting from the precipitation of opal-CT at decreasing pH condition caused by the release of H+ during diagenetic alteration of pumice fragments. Because of the acidic smectite, the low-grade mineral resources from the Beomgockri Group may be applicable to the adsorption industry as the raw materials of acid clays and bed-soil.