• Economic and Environmental Geology
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• v.36 no.3
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• pp.225-232
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• 2003

Three piston cores. obtained from the northwestern Ulleung Basin of the East Sea, are analyzed to study the tephrostratigraphy of the late Quaternary core sediments and to reveal the comparative characteristics of the tephra layers. The cores consist mainly of the muddy sediments that are partly interbedded with lapilli tephra and ash layers. The muds are further divided into hemipelagic and turbiditic mud facies. The hemipelagic facies is dominated by bioturbated mud and crudely laminated mud, whereas the turbiditic facies includes mainly thinly laminated mud and homogeneous mud, and often alternates with non-turbiditic muds. According to microscopic observation and EDX analysis, three tephra layers of the Ulleung-Oki (U-Oki; ca. 9.3 ka), Aira-Tanzawa (AT: ca. 22~24.7 ka) and Ulleung-Yamato (U-Ym; ca. 25~33 ka) are identified in the study cores. Among these, the U-Oki and U-Ym layers, originating from the Ulleung Island, consist mainly of massive-type glass shards with alkali feldspar. Both of the tephra layers contain a lower content of SiO$_2$ (57~66.5 wt.%) and a higher content of Na$_2$O+K$_2$O (11~16 wt.%) than the AT layer (SiO$_2$=75~78.5 wt.%, Na$_2$O+K$_2$O=6.5~9 wt.%) that consists of typical plane-type and/or bubble-wall glass grains. Compared with that of the U-Ym layer, a sedimentary facies of the U-Oki layer is very thick and contains three stratigraphic units, probably due to relatively large and different supplies of pyroclastic sediments. Thus, the eruption of Ulleung Volcano (ca. 7,300 B.C.) is thought to have had a more powerful effect on depositional environment than the U-Ym eruption.

• The Korean Journal of Quaternary Research
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• v.15 no.2
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• pp.83-91
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• 2001

The environmental change during the upper Holocene was restored at Kimpo alluvial plain on the left bank of Han-river near the Yellow Sea according to the results of pollen analysis and carbon dating, based on the sea-level change from Ilsan area. Pollenzone I (5.8~7.0 m.a.s.l.) was the period of AP-dominance, including mostly Alnus. Study area was under the lagoon or swamp environment influenced by Flandrian transgression during 5,000~3,200 BP. Pollenzone II (7.0~7.4 m.a.s.l.) was the period of Spore & NAP-dominance. It represents that the vegetational environment was changed to drier condition by falling underwater surface caused by sea-level regression, and influenced by human activity during 3,200~2,300 BP. Subzone I a represented the characteristics of the climax of transgression. During subzone I b, herbs with the dominant Alnus were increased gradually, and it was correlated to the stagnation of high sea-level. Subzone II a was the dominant period of Spore by the gradual falling of sea-level. After that, the study area in swamp was emerged to the lowland by the fallen sea-level and herbs, especially Gramineae increased suddenly during Subzone II b. The sudden increase of NAP such as Artemisia, Chenopodiaceae and Umbelliferae with Gramineae during this period indicates the beginning of agriculture at this study area.

• The Korean Journal of Quaternary Research
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• v.3 no.1
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• pp.69-85
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• 1989

The depositional environments of the Pyung-Ahn Group sedimentary rocks, Jeongseon-Kun, Kangweondo, Korea are investigated. The environments are understood to be characteristic transitional from a typical shallow marine to a typical continental environment. Such transitional conditions are also understood in various parts of Quaternary and modern environment on the earth. In particular, the absence of detrital feldspar sand grains in the Manhang and Keumcheon Formation Sandstone body is described firstly in Korea, and the fact and possible mechanism are discussed.

• Economic and Environmental Geology
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• v.34 no.6
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• pp.555-571
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• 2001

The dynamic evolution of the Chugaryeong fault valley is studied by paleomagnetic works on 163 samples at 16 sites from Late Cretaceous and Quaternary volcanic rocks in the valley. Conglomerate test and stepwised thermal/alternating field demagnetization indicate that all the characteristic directions are of primary origin. Paleomagnetic pole ponsition(216.8$^{\circ}$E/7l .6$^{\circ}$N; dp=7.1$^{\circ}$, dm=10.0$^{\circ}$) for the upper par of the Jijangbong Volcanic Complex Is indistinguishable from the coeval retference pole position from the Gyeongsang Basin, which further substanciates the reliability of the Paleomagnetic data. This indicates the study area has not undergone any tectonic rotation since Late Cretaceous by uy significant reactivation of the Chugaryeong fault valley. The Quaternary pole position (134.2$^{\circ}$E/86.5$^{\circ}$N; $A_{95}$=7.1 $^{\circ}$) from the Jeongog Basalt reflects the present geocentric axial dipole field for the area, supporting the above conclusion. Unlike the upper part, paleomasnelic directions of the lower part of the Jijangbong Volcanic Complex show random distrinution between sites. We interpret that the early stage of the volcanic activity was created by sinistral strike slip motion of the Chugaryeong fault during early Late Cretaceous. The creation and evolution of the Chugaryeong fault valley emphasize the significance of the kinematic FR (folding ruler) model in east Asia.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.1
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• pp.84-92
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• 1985

This experiment was carried out to study the morphological traits, yield and yield components of barley cultivars - Kangbori, Olbori and Suwon 18 - on different seeding dates. It appeared generally rapid development of young spike from late stage of floret differentiation (X stage) to complete it at heading stage. Young spike appeared more influencials by the different seeding dates rather than years and cultivars. Stem started the development from late stage of spikelet differentiation (VII stage) to early stage of floret differentiation (IX stage), indicating the continuing development from basal to upper internodes. Number of spikes per unit area showed more effect in seeding date rather than cultivar and year. However, number of kernels per spike and 1,000 kernel weight affected more due to years rather than cultivar and seeding date. It was significantly difference in grain yield according to different seeding dates.

• The Korean Journal of Quaternary Research
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• v.12 no.1
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• pp.9-16
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• 1998

이글은 프랑스 남서부 지방에 있는 빠또 바위그늘유적의 제 2문화층(22,000 B.P.)에 서 나온 석기를 만드는데 쓰였던 돌감과 그 사용에 대해서 살펴보았다, 빠또 유적의 석기는 대부분 부싯돌로 만들었는데 이들은 원산지에 따라서 유적지 가까운 곳에서 쉽게 구할수 있 는것과 멀리서 가져온거 두 종류로 크게 나눌수 있다. 돌감의 사용은 석기에 따라서 크게 달라서 잔손질된 연모를 만드는데 외래암질 특히 베르쥬락지방에서 찾을 수 있는 부싯돌이 많이 쓰였다 또한 잔손질된 연모사이에서도 석기 유형에 따라서 돌감이 다르게 쓰여서 일상 생활에서 오랜동안 자주쓰일 연모를 만들 때 먼곳에서 가져온 좋은 질의 돌감을 우선적으로 썼던 것으로 나타났다, 이렇게 볼 때 돌감 구하기와 밀감의 쓰임새가 빠또 2문화층에 살았 던 사람들의 석기제작 과정에 가장 중요한 영향을 끼쳤다고 할수 있겠다.

• Journal of Digital Convergence
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• v.6 no.2
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• pp.33-40
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• 2008

Alvin Toffler는 인류 발전 과정을 세 가지 변화의 물결, 즉 유목 채집 사회에서 농경 사회로의 변화, 산업혁명에 의한 농경 사회에서 산업 사회로의 변화, 그리고 1950년대부터의 후기 산업화 사회로의 변혁으로, 산업 사회에서 정보 사회로의 변혁이 일어나기 시작했으며 탈대량화, 다양화, 지식기반 생산과 변화의 가속이 시작된 시기였다. Herman Maynard와 Susan Mehrtens는 ICT (Information Communication Technology: 휴대폰 등), 인터넷의 발달로 제4의 물결이 시작되고 있다고 주장한다. 이전의 사회 변혁들은 물질 생산이 따르는 가시적인 변혁들이었으나, 디지털 혁명은 시민사회의 참여 확대를 통한 민주주의의 진화된 형태를 가능하게 하고 있다. 지금 우리가 경험하고 있는 제4의 물결의 시작은, 시민사회의 정책 참여와 견제가 효과적이고 효율적으로 이루어지기 시작하는 초고도 정보화 사회의 시작을 의미하며, 정책 결정 자들은 정책 결정 과정에서 그들이 보유하던 절대 영향력의 일부분을 시민사회에 이양됨을 막을 수 없을 것이다. 이러한 대변혁의 시대에 관료주의, Digital Divide, 그리고 시민 참여와의 상관관계를 이해하는 것은 매우 중요하다. 본 논문에서는 시민 참여에 대한 관료주의의 방침과 태도, 제4의 물결의 정책 민주화와 Digital Divide로의 영향 분석을 통하여 정책 결정 자들과 그들의 환경으로의 파급 효과를 논증한다. 본 연구는 이러한 분석과 논증을 통하여, 정책조직들과 시민사회와의 신세기의 바람직한 동반자적 입지 구축에 기여 할 것이다.

• Journal of The Korean Society of Grassland and Forage Science
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• v.18 no.4
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• pp.323-328
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• 1998

A field experiment was carried out to determine the effects of chemical and mechanical treatment at mowing on the field drying rate and hay quality of autumn oat (Avena sativa L.). The chemical drying agent/mower conditioner ($K_2CO_3$ 2%, conditioning, $K_2CO_3$ 2% + conditioning and control) were treated at different harvest stages (late boot, heading and bloom stage) for hastening hay manufacture in the autumn of 1996. After field dry, square bales were made by hay baler, and the dry matter(DM) loss and visual estimation of oat hay were evaluated after storing two months. In general, the field drying rate of oat was slow, regardless of harvest stage. Mechanical and chemical + mechanical treatment were effective, but the effectiveness of chemical alone was very low. With mower conditioning, the duration of field dry was shortened by 2 days compared with control. The DM loss of hay was higher at boot stage(51.4%) than at heading stage (21.1%), and the DM loss was reduced by mechanical and chemical + mechanical combined treatment. The visual score (leafiness, green color, odor and softness) of hay after storing was high in mechanical and chemical + mechanical, but the score by chemical alone was very low. The nutritive value (ADF, NDF, digestibility, and relative feed value) of hay was also high with treatment of mechanical and chemical + mechanical, but the quality by chemical alone was similar compared with control. In conclusion, mower conditioning can enhance the field drying rate of autumn oat, but the drying efficiency of the chemical drying agent was very low. However, it is suggested that hay-making of oat in autumn is very hard though using mower conditioner.

• The Korean Journal of Quaternary Research
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• v.15 no.2
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• pp.63-73
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• 2001

In total, 29 $^{14}C$ dates were obtained from Paleolithic sites in the Korean peninsula. If not the dates from the Sorori peat layers, the number will be less than 20. Low boundary of Upper Paleolithic could be estimated by some early of the dates from Blade stone industries. Couple of $^{14}C$ dates indicate that beginning of Upper Paleolithic industries could approach to 40 K BP, but it is premature to establish fine chronology of Upper Paleolithic. Some of the $^{14}C$ dates of microlithic industries probably represent too earlier age than generally thought. Tentatively, the beginning of microlithic industries may go back to an age of slightly older than 20 K BP, as indicated in Janghungri, Sokchangni, Noeundong etc. The obtained $^{14}C$ dates at present are very important for construction of Paleolithic chronology. but it is necessary to accumulate for more $^{14}C$ dates in future along with results from other dating techniques and to reconstruct site formation processes for obtaining objective age of stone industries.

• Journal of The Geomorphological Association of Korea
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• v.27 no.1
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• pp.33-45
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• 2020

A number of unconsolidated deposits, consisting of a layer of gravels and silt, are found in Dangjeong-ri, Seocheon-gun in the western coast. From below in the stratigraphic sequence, the gravel layer ranging up to a maximum thickness of about 2 meters is interpreted as being formed by fluvial processes of an old channel (Dangjeong S.), and the overlying silt or sandy silt layer of 2 to 3 thickness meters is assumed to be emerged paleo-tidal sediments which was deposited in low tidal-energy environments. As the results of rock surface IRSL datings, the depositional ages of gravels are confirmed as ca. 78,000 ~ 83,000 years BP, indicating that the layer was formed in response to a high-stand sea level of MIS 5a along the Dangjeongcheon estuary. It is presumed that the relative height of 4.5 meter between the altitude of the stream bed (9.5 m) and the altitude of the bedrock boundary in the gravel layer (14 m) indicates the uplift amount since deposition. Paleo-sedimentary environments and an altitude of paleo-shoreline in the study area will be discussed with additional age dating focused on the silt layer.