• 한국제4기학회:학술대회논문집
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• 한국제4기학회 1990년도 국제심포지움 요약문
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• pp.66-66
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• 1990

No abstract, See full-text

• 한국제4기학회:학술대회논문집
• /
• 한국제4기학회 1990년도 국제심포지움 요약문
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• pp.67-67
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• 1990

No abstract, See full-text

• 한국제4기학회:학술대회논문집
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• 한국제4기학회 2002년도 한몽 제1차 합동세미나 발표요지
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• pp.90-90
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• 2002

• Elastomers and Composites
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• 제51권3호
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• pp.188-194
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• 2016

In this study, novel quaternary plastomers consisting of ethylene, 1-hexene, high ${\alpha}$-olefin, and divinylbenzene were prepared using Zr metallocene catalyst, borate type cocatalyst, and tri-isobutylaluminium. The molar ratio changes of 1-hexene and high ${\alpha}$-olefin (1-octene, 1-decene, and 1-dodecene) had an effect on the properties of the quaternary plastomers. The structure of the quaternary plastomers was characterized using $^1H$ NMR. Molecular weight properties, crystallinity, and thermal properties of the plastomers were determined by GPC, WAXS, and DMA, respectively. Compared with the terpolymers prepared in our previous study, molecular weight and molecular weight distribution of the quaternary polymers were very similar, whereas glass transition temperature ($T_g$) was very low. Also, hardness and tensile properties of the quaternary plastomers were measured.

• Journal of Communications and Networks
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• 제14권3호
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• pp.230-236
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• 2012

Based on the known binary sequence sets and Gray mapping, a new method for constructing quaternary sequence sets is presented and the resulting sequence sets' properties are investigated. As three direct applications of the proposed method, when we choose the binary aperiodic, periodic, and Z-complementary sequence sets as the known binary sequence sets, the resultant quaternary sequence sets are the quaternary aperiodic, periodic, and Z-complementary sequence sets, respectively. In comparison with themethod proposed by Jang et al., the new method can cope with either both the aperiodic and periodic cases or both even and odd lengths of sub-sequences, whereas the former is only fit for the periodic case with even length of sub-sequences. As a consequence, by both our and Jang et al.'s methods, an arbitrary binary aperiodic, periodic, or Z-complementary sequence set can be transformed into a quaternary one no matter its length of sub-sequences is odd or even. Finally, a table on the existing quaternary periodic complementary sequence sets is given as well.

• 한국제4기학회지
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• 제10권1호
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• pp.19-26
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• 1996

This review gives an information on the oxygen isotopic composition of car-bonate and utility of paleotemperature equations to reconstruct the paleoenvironment in the late Quaternary paleoclimatic studies. The introduc-tion of various paleotemperature equations is described with respect to the de-velopment and usefulness. In addition the calculation of paleotemperature in the paleoceanographic and paleoclimatic research is constrained to provide more precise and correct approach in the interpretation of paleotemperature.

• 한국제4기학회지
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• 제1권1호
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• pp.3-20
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• 1987

韓半島에 분포하는 第四紀 地層들에 대한 기존의 지질학적 연구는 극히 미소한 편이였으며 계곡이나 평야등지에 분포하는 沖積層들이 第四紀 동안의 유일한 地層으로 대표되어 왔다. 따라서 韓半島의 第四紀 地質時代는 그 대부분이 堆積보다는 浸蝕이 우세하였던 시대로 認識되었으며 기존의 지질도들에 의하면 沖積層의 형성시기를 제외한 第四紀는 不整合으로 표시되었다. 이는 韓半島의 지질과 지형이 第四紀 地層이 형성되어 현재까지 殘存해 있을 수 있는 커다란 堆積盆地를 이루지 못한데 있다. 이와 반면에 現 地形의 산록이나 해안주변등에서는 서로 堆積 환경과 時代를 달리하는 第四紀 地層들이 소규모적이나 수직적으로는 良好한 분포를 보이는 지역들을 발견할 수 있다. 그 대표적인 예로서 동해안의 3개지역(북평, 울진, 포항)과 서해안의 고창지역에서는 砂礫이나 砂質粘土등으로 구성되어 있는 第四紀 地層들이 발달하여 있다. 本 地層들의 분포위치, 堆積相 및 古地磁氣 연구로서 地質時代를 규명하였으며 堆積構造와 粘土광물 분석등을 통하여 이들의 古環境을 해석하여 第四紀 동안 韓半島의 地質史를 규명하였다.

• 한국제4기학회지
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• 제18권2호통권23호
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• pp.93-98
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• 2004

• 대한수학회지
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• 제45권3호
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• pp.621-630
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• 2008

In this paper, we provide a complete list of 177 equivalence classes of primitive even 2-regular quaternary positive definite quadratic forms and their discriminants. All of them have class number 1.

• 대한수학회논문집
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• 제34권1호
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• pp.27-41
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• 2019

We determine explicit formulas for the number of representations of a positive integer n by quaternary quadratic forms with coefficients 1, 2, 5 or 10. We use a modular forms approach.