• The Korean Journal of Quaternary Research
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• v.7 no.1
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• pp.41-68
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• 1993

In the loess-paleosol sequences from central Great Plains, U.S.A., variation in magnetic susceptibility, FD, NRM have been proven to be excellent proxy for paleoclimate, and the standard interpretation is that climatic processes have enhanced the rock magnetic intensities. By using mineral magnetic properties, we show the magnetic signal is due to pedogenesis during the warm and possibly wet interglacials and interstadials. Other proxy records, such as stable carbon isotope and phytolith, are in good agreements with the magnetic records.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.1C
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• pp.9-14
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• 2009

In this paper, using the binary (N,M,L,1) low correlation zone(LCZ) sequence set with specific property, we propose the construction method of a quaternary LCZ sequence set with parameters (2N,2M,L,2). The binary LCZ sequence using this method must have period $N{\equiv}3$ mod 4, balance property, and specific correlation property. The proposed method is modified from the construction method of binary LCZ sequence set by using binary LCZ sequence with specific condition proposed by Kim, Jang, No, and Chung[4].

• The Korean Journal of Quaternary Research
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• v.23 no.1
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• pp.38-41
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• 2009

Results from the most recent decade of Mars' missions to Mars highlight a liquid water and water-ice sculpted landscape. Evidence includes layered sedimentary sequences with weathered outcrops, debris flows, fluvial valleys, alluvial fans, deltas, glacial and periglacial landscapes, and geochemical/mineralogical signatures of aqueous activity, including the formation of sulfates and clays, and the leaching and deposition of elements such as potassium, thorium,and iron. Such evidence indicates weathered zones and possible paleosols in stratigraphic sequences, transport of water and rock materials to sedimentary basins, and the possible formation of extensive transient lakes and possibly transient oceans on Mars. This new evidence is consistent with Viking-era geologic investigations that reported magmatic-driven flooding, ponding to form large water bodies in the northern plains, and transient (tens of thousand of years) hydrological cycles. It may even indicate aqueous activity at present. Both endogenic (magmatic driven) and exogenic (both impact cratering and changes in orbital parameters) have influenced paleohydrologic and environmental change on Mars. Abundance of water and dynamic activity would be decisively important for the possibility of past and present life on Mars.

• Bulletin of the Korean Chemical Society
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• v.32 no.8
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• pp.2633-2636
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• 2011

A new type of ionic liquid based on N-(3-aminepropyl)imidazolium iodide, called IIQAI, which consists of imidazolium and quaternary ammonium salt, and APII-(hydroxyethyl, propyl, hexyl) were synthesized and used as ionic liquid in dye-sensitized solar cells. APII-hexyl is solid, whereas IIQAI, APII-(hydroxyethyl, propyl) are viscous liquids. The synthesized ionic liquid showed relative thermal stability compared to the commercial ionic liquid of DMII. Among them, IIQAI was more stable than the other ionic liquid because of the two salt groups. APII-hydroxyethyl, which contains two hydroxyl groups, showed low viscosity with good flow. New types of ionic liquids were examined by $^1H$-NMR spectroscopy, thermo gravimetric analysis (TGA). IIQAI enabled a solar energy conversion efficiency of 6.3%, which is slightly higher than that of the referenced (DMII, 6.2%).

• Journal of Advanced Navigation Technology
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• v.16 no.1
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• pp.62-69
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• 2012

Multiple-control Toffoli(MCT) gates are macro-level multiple-valued gates needing quantum technology dependent primitive gates, and have been used in Galois Field sum-of-product (GFSOP) based synthesis of quantum logic circuit. Reversible logic is very important in quantum computing for low-power circuit design. This paper presents a reversible GF4 multiplier at first, and GF4 multiplier based quaternary MCT gate realization is also proposed. In the comparisons of MCT gate realization, we show the proposed MCT gate can reduce considerably primitive gates and delays in contrast to the composite one of the smaller MCT gates in proportion to the multiple-control input increase.

• The Korean Journal of Quaternary Research
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• v.20 no.1 s.26
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• pp.1-8
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• 2006

Many boring investigations were achieved in Youngjong-North tidal flat to construct the Incheon International Airport Expressway. Vertical sedimentary profile of this tidal flat has been studied by analyzing these boring data. The deposits of Youngjong-North tidal flat are about 30 meters thick, and the sedimentary layers consist of basal gravel, lower mud, middle silt, middle mud, and upper silt layers in ascending order. Semi-consolidated and oxidized belt with yellowish brown color, which appears above or within middle mud layer, exists in $-3{\sim}-5$ meters altitude. There are some stratigraphical problems to admit the top surface of this oxidized belt as the unconformity surface between Holocene and Pre-Holocene tidal flat deposit.

• The Korean Journal of Quaternary Research
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• v.12 no.1
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• pp.17-30
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• 1998

연구지역인 대관령 서쪽 산지 사면은 진부에서 동쪽으로 고속도로를 따라 약 21km 떨어진 대관령까지이며 해발고도는 500∼900m 지형경사는 3.3%이다. 1989년 5월∼1992년 5 월에 진부에서 대관령 쪽으로 영동고속도로를 따라 진부(고도 544m) 간평기(고도 576m) 유 천리(고도 600m) 싸리재(고도800m) 대관령(고도 842m)등의 5개지점을 정하여 일 강수량을 측정하였다 각 고도별 일 강수량 자료를 기초로 한반도의 지상 기압배치형에 따른 대관령 서쪽 산지의 고도별 강수량 분포의 특성을 고찰하였다,. 이결과를 용약하면 다음과 같다. 총 강수일 258일을 지상 기압배치형(기압골, 저기압, 시베리아고기압, 장마전선, 고기압, 태풍, 오호츠크해고기압)에 따라 7가지 형으로 분류하였다, 이들중 기압골이 나타난 날이 113일로 제일 많고 오호츠크해고기압이 나타난 날은 8일로 가장적었다. 고도별 일평균 강수량은 태 풍이 나타났을 때 17,5∼54,4mm로 제일많았고 시베리아고기압이 나타났을 때는 5.9∼ 19.8mm로 제일 적었다, 대관령 서쪽 산지 사면에서 강수량이 제일 많은 고도는 대관령이고 제일적은 고도는 간평리이다, 태풍과 오호츠크해고기압이 출현한 경우는 고도가 증가할수록 강수량도 많아졌다. 간평리와 대관령 고도의 강수량 분포에 관한 사례분석(1989.5∼1991.12) 에서 기압골, 저기압, 장마전선등이 나타난 36일 시베리아고기압이 나타난 1일은 간평리가 대관령보다 강수량이 많았다.

• The Korean Journal of Quaternary Research
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• v.15 no.1
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• pp.47-52
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• 2001

April∼August precipitation (141 years : A.D. 1858∼1998) of Mt. Sorak region (East-central Korea) was reconstructed using a tree-ring chronology of Pinus densiflora sampled from Beakdam Shelter area. During the reconstructed Periods, dry periods were 1880∼1887, 1893∼1901 and 1922∼1938, and wet one 1906∼1918. In the long-term variation, the late 19th and early 20th century were drier than the late 20th century. Major wet/dry periodicities in April∼August precipitation series reconstructed were 3.16 and 4.14 years, indicating that short-term variation were more prominent than long-term one.

• Journal of the Korean Chemical Society
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• v.36 no.6
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• pp.933-940
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• 1992

Calix[6]arene react with formaldehyde and secondary amines to yields water soluble Mannich bases which can be converted to the corresponding quaternary salts. Treatment of the quaternary salts with a nucleophile such as cyano, ethoxy, and hydride yields p-substituted calix[6]arenes. Calix[8]arene too react with formaldehyde and diallyl amine to yield a water soluble Mannich base. The transport of neutral arenes through an aqueous phase along a concentration gradient mediated by those of water soluble calixarenes as molecular carrier was studied in a U-type cell. Naphthalene, anthracene, pyrene, and fluoranthene are tested as a neutral solid guest compounds for the transport experiment.

• Journal of the Korean Magnetic Resonance Society
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• v.23 no.1
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• pp.26-32
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• 2019

${\alpha}B$-crystallin (${\alpha}BC$) is a member of a small heat-shock protein (sHSP) superfamily and plays a predominant role in cellular protein homeostasis network by rescuing misfolded proteins from irreversible aggregation. ${\alpha}BC$ assembles into dynamic and polydisperse high molecular weight complexes containing 12 to 48 monomers; this variable stereochemistry of ${\alpha}BC$ has been linked to quaternary subunit exchange and its chaperone activity. The chaperone activity of ${\alpha}BC$ poses great potential as therapeutic agents for various neurodegenerative diseases. In this mini-review, we briefly outline the recent advancement in structural characterization of ${\alpha}BCs$ and its potential role to inhibit protein misfolding and aggregation in various human diseases. In particular, nuclear magnetic resonance (NMR) spectroscopy and its complimentary techniques have contributed much to elucidate highly-dynamic nature of ${\alpha}BCs$, among which notable advancements are discussed in detail. We highlight the importance of resolving the structural details of various ${\alpha}BC$ oligomers, their quaternary dynamics, and structural heterogeneity.