• Tunnel and Underground Space
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• v.19 no.5
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• pp.421-431
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• 2009

As an indirect method, Schmidt hammer test has been employed to investigate correlation between uniaxial compressive strengths and blow values. To conduct the experiment, researchers have examined 11 types (1,417 blocks) of rock, which include igneous, metamorphic and sedimentary rocks in Korea. Every kind of rocks shows different blow behaviors in which correlations of rocks have been analyzed, thus leading to results in new formulas for strength predictions. Cross-check for reliability demonstrates high confidence. Newly proposed test method is highly valued for future research on Korean rocks.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.22 no.1
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• pp.11-15
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• 1977

Natural infection of purple stain seemed to be higher in early maturing lines comparing to late maturing group. It was positively correlated with length of the period from flowering to maturity and significantly associated with weather conditions during the maturing period.

• 한국해양학회지
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• v.20 no.2
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• pp.49-60
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• 1985

The interrelationships between distribution of phytoplankton and hydrographical conditions were studied from December 1983 to July 1984 in Yeongil Bay. The temporal variation of phytoplankton abundance seems to be mainly influenced by the vertical stability of water column and the freshwater run-off accompanied with possible nutrient input. The temporal progression of dominant species shows general succession pattern, especially skeletonema costatum was found a dominant species in each month. Although the differences between concentration of chlorophyll a and abundance of phytoplankton may be caused by cell size variation, during the study period they show felatively good linear manner. The phytohydrographic region based on multivariate analysis reflects the relationships between hydrographical condition and distribution pattern of phytoplankton.

• Korean Journal of Environment and Ecology
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• v.18 no.2
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• pp.150-157
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• 2004

To investigate the vegetation structure of mountain ridge from Suryeong to Sosagogae, 10 plots(500$m^2$) set up with random sampling method were surveyed. Three groups, Quercus dentata-Fraxinus rhynchophylla community, Quercus mongolica-Fraxinus rhynchophylla community, Quercus mongolica community, were classified by cluster analysis. Quercus mongolica was found as a major woody plant species in the ridge area from Suryeong to Sosagogae. Quercus dentata and Fraxinus rhynchophylla were occupied partly in lower elevation. Species diversity(H') of investigated groups was ranged from 1.7295∼2.6525 and it was similar to that of the ridge area of the national parks in Baekdudaegan. Rare and endangered species, Rhododendron tschonoskii recorded from the list of the Forest Administration distributed between the rocks on the top of the Sambongsan, the long-term habitat monitoring might be required.

• Proceedings of the Korea Information Processing Society Conference
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• 2011.11a
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• pp.151-154
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• 2011

유비쿼터스 협업 (Ubiquitous Collaboration)은 유비쿼터스 환경에서 다양한 이기종 디바이스 (PC, Tablet PC, Smart Phone, etc)들이 유무선망을 통해 언제 어디서나 원하는 서비스를 주고 받을 수 있는 시스템으로 시간과 장소에 상관없이 다양한 데이터를 주고 받을 수 있다. 스마트폰의 보편화, 하드웨어 / 소프트웨어 그리고 무선망의 진화로 협업의 중요성은 점점 증가하고 있다. 본 연구에서는 스마트폰 환경에서 이미지, 도형, 텍스트 등의 도구를 사용 협업하는 인터랙티브 화이트보드 어플리케이션(Interactive Whiteboard Application on Smart Phone)을 사용하여 다양한 환경의 사용자들이 서로 다른 이기종 디바이스와 함께 통신하는 방법을 보인다. 또한 서로 다른 이기종 디바이스 간 그룹 통신에서 오는 동기화(Synchronization), 비동기화(Asynchronization), 또한 다른 화면 크기로 부터 발생되는 서로 다른 이미지 크기 표현문제를 극복하기 위한 사용성 평가실험(Usability Test)을 통하여 연구의 타당성 및 우수성을 증명해 보이고자 한다.

• Investigative Magnetic Resonance Imaging
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• v.1 no.1
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• pp.125-129
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• 1997

Purpose: The aim of this study was to find correlation between the expression of epidermal growth factor receptor (EGFR) and MR findings in the brain glioma. Materials and Methods: MR features including edema, margin, necrosis, heterogeneity, hemorrhage and contrast enhancement were retrospectively analyzed with preoperative MR images in 41 patients with proven brain gliomas (8 low grade astrocytomas, 12 anaplastic astrocytomas, 21 glioblastoma multiformes). Immunohistochemical study of EGFR was done and their expressions were graded by both stained distribution and intensity. Correlation analysis between the MR features and EGFR expressions was done. Results: Peritumoral edema was correlated with both distribution (r=0.71, p=0.00) and stain intensity (r=0.69, p=0.00) of EGFR expression. Other MR features showed no statistical correlation with EGFR expression. Conclusion: MRI is useful in evaluation of brain glioma, and peritumoral edema is useful finding that suggests EGFR expression as well as malignant histopathologic grade of the tumor.

• Microbiology and Biotechnology Letters
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• v.30 no.3
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• pp.282-286
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• 2002

Seasonal succession of algae and water quality parameters were studied in artificial reservoirs in Daegu city from 2000 to 2001. The algal succession was evaluated with respect to dom-inant class and their frequencies. Succession order of algae in two reservoirs was : Bacillariophyceae longrightarrow Chlo-rophyceae longrightarrow Cyanobacteria longrightarrow Bacillariophyceae longrightarrow Bacillariophyceae longrightarrow Cyanobacteria longrightarrow Cyanobacteria longrightarrow Cyanobacteria. This succession order was different from other studies. The local environment condition maybe affects the succession of algae in these reservoirs. As result of correlation analysis between algal biom-ass and water quality parameters, we got low correlation coefficients. Also we got low correlation coefficients between chlorophyll-a and algal biomass. Between chlorophyll-a and water quality parameters, we got high correlation coefficients. An approach having attention to cell biovolume rather than cell number is made to understand the algal community and the ecosystem of reservoir.

• International Journal of Highway Engineering
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• v.13 no.1
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• pp.169-175
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• 2011

Strength is one of the very important factors to evaluate the physical properties of concrete. Aggregate forms the most parts in concrete. Cement as a binder in concrete is also closely related to strength. This experiment was tested to understand the effect of the characteristics of aggregate and cement on the relationship between concrete compressive strength and Shear Wave velocity. It was experimented by the different types of cement and maximum coarse aggregate sizes. Type I cement and rapid setting cement was used. Aggregates from three different regions were used. Aggregate of 19mm and 13mm maximum coarse aggregate sizes was used for grading. The relationship between compressive strength and Shear Wave velocity was tested under the condition of same mixture. LA wear test was used to quantify the characteristics of aggregate. As a result, the relationship between concrete compressive strength and Shear Wave velocity was affected by the types of cement, but regular relationship was appeared regardless of types of aggregate, grading and abrasion ratio.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.20 no.3
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• pp.230-236
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• 1987

The correlation between tintinnid and dinoflagellate by means of seasonal variation of standing crops was investigated at two selected stations in Masan Bay, well-known as a red tide zone in southern coastal waters of Korea, during the period from January 1981 to December 1982. The most dominant dinoflagellates mainly belonged to $20-60\;{\mu}m$ of size class, and Gymnodinium and Prorocentrum were predominant from spring to summer season. Of tintinnid, Favella spp. were most dominant and associated with dinoflagellate blooms at the same season. Especially, Favella spp. were most positively correlated with $40-60\;{\mu}m$ size class of dinoflagellate, and also represented higher multiple corrleation with outer station (St.2), comprising relatively large species of Gymonodinium and Protogonyaulax, than with inner station (St. 1), dominated by Prorocentrum blooms. Thus, the interspecific food selection by size and morphology between tintinnid including Favella and dinoflagellate is recognized and it is considered to be an important factor influenecing on the prey-predator relationship in lower trophic level in the surveyed area.

• Geophysics and Geophysical Exploration
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• v.21 no.4
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• pp.220-230
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• 2018

When thermal conductivity of rock is measured with PEDB (Portable Electronic Divided Bar) in a laboratory, it can be greatly influenced by the change of room temperature. Therefore, measuring the thermal conductivity in a thermo-hygrostat is necessary, where it can remain in its constant temperature and humidity condition. In this study, a system for thermal conductivity measurement in a thermo-hygrostat has been set up and the thermal conductivities for the 45 samples collected from GH3 and GH4 boreholes in Ulleung Island have been measured both in dry and saturated conditions. Also, the correlations between those thermal conductivities, density, and effective porosity have been discussed. As a result of correlation analysis among the thermal conductivity, density, and effective porosity, it showed higher correlation with dry samples than saturated samples. Especially, thermal conductivity ratio between saturated and dry conditions shows very high correlation ($R^2=0.90$) with effective porosity.