• Restorative Dentistry and Endodontics
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• 제7권1호
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• pp.17-24
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• 1981

The purpose of this study is to compare the shape of the apical regions of root canals after instrumentation by various enlarging instruments. 120 extracted, single-rooted human teeth were seperated into 4 experimental groups. Each group provided 30 teeth for experimental use. Group 1 root canals instrumented by the hand-operated Reamer. Group 2 root canals instrumented by the hand-operated H-file. Group 3 root canals instrumented by the hand-operated K-file. Group 4 root canals instrumented by the automated Giromatic file. The results were as follows: 1. The degree of the roundness of the apical regions of root canal walls: 1) Hand-operated instruments were superior to the automated Giromatic file. 2) The Reamer was the most effective instrument among hand-operated instruments 3) There was little difference between the H-file and the K-file. 2. The degree of the smoothness of the apical regions of root canal walls: 1) Root canal walls instrumented by the hand-operated Reamer, H-file and, K-file were generally smooth, and there was little difference among them. 2) Root canal walls instrumented by the automated Giromatic file showed many irregular canal walls. 3. The existance of organic debris in the apical regions of root canals: All organic debris is not removed from root canals, and there was little difference between hand-operated instruments and the automated Giromatic instrument in removing organic debris.

• 한국농공학회지
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• 제43권4호
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• pp.57-68
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• 2001

It is matter of common knowledge to give impetus to the water resources development to cope with increasing demand and supply for the water utilization project including agricultural living and industrial water owing to the economic and civilization development in recent years. Regional design rainfall is necessary or the design of the dam reservoir levee and drainage facilities for the development of various kinds of essential waters including agricultural water. For the estimation of the regional design rainfall classification of the climatologically an geographically homogeneous regions should be preceded preferentially This study was mainly conducted to derive the optimal regionalization of the precipitation data which can be classified by the climatologically and geographically homogeneous regions all over the regions except Cheju and Wulreung islands in Korea. A total of 65 rain gauges were used to regional analysis of precipitation. Annual maximum series for the consecutive durations of 1, 3, 6, 12, 24, 36, 48 and 72hr were used for various statistical analysis. Both K-means clustering and mean annual precipitation methods are used to identify homogeneous regions all over the regions. Nine and five homogeneous regions for the precipitation were classified by the K-means clustering and mean annual methods, respectively. Finally, Five homogeneous regions were established by the trial and error method with homogeneity test using statistics of $\chi$$^2$ distribution.

• 한국토양동물학회지
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• 제1권2호
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• pp.110-119
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• 1996

The authors investigated the spider fauna of Mt. Yebongsan from May 1994 to Aug. 1996. In this paper, 265 species from 21 genera, and 28 families were identified and compared with those from islands geographical with differing i.e., Is. Paikryung-do, Is. Chin-do, and Is. Ulrung-do distribution and climate. Spiders from 45 palaearctic regions(3.69%), 13 holarctic regions(1.06%), 4 oriental regions(0.32%) and 5 cosmopolitans(0.41%) are identified. Various methods were used for collecting specimens during the period including pitfall, beating, sweeping and looking up-down.

• 디지털융복합연구
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• 제10권8호
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• pp.233-237
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• 2012

정보통신과 관련된 기술들이 매우 급속한 속도로 발전 진화되어 감에 따라 다른 산업과의 융합 현상 또한 다양하면서도 급속도로 확산되어 가고 있다. 이들 융합현상을 종합적으로 분류해 보면 전통적인 제조산업 분야(자동차, 조선, 기계, 로봇, 섬유등), 실 생활공간과 밀접하게 연관되어 있는 건설(그린 시티), 삶의 질 향상에서 오는 의료산업과의 융합등이 대표적이라 할 수 있다. 본 연구에서는 우리의 삶의 공간과 밀접하게 연관된 스마트 그린시티에 대한 내용을 다루었다.

• Annals of Clinical Neurophysiology
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• 제1권2호
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• pp.154-159
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• 1999

Magnetoencephalography (MEG), the measurement of magnetic fields produced by neuronal current associated with normal and pathologic brain activities, is a totally noninvasive method for localizing functional regions of the brain. During the past several years, many clinical research centers are working to expand various fundamental functional brain regions, which can be easily localized, as well as to characterize magnetic abnormalities which accompany a wide variety of cerebral disease. At present, MEG is used in a number of clinical centers throughout the world for the presurgical functional localization of eloquent cortex, and for the non-invasive localization of epileptiform activity. And also, non-invasiveness means that it can be used for screening and repetitive follow-up measurement without concern for adverse effects. As procedures for activating various functional brain regions are standardized, and as the effects of specific cerebral diseases on the MEG are carefully documented in controlled studies, the number of routine neurological applications for MEG will increase significantly. In this paper, the basic principles of MEG are reviewed briefly with its clinical application to neurologic disease.

• 한국식물학회:학술대회논문집
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• 한국식물학회 1987년도 식물생명공학 심포지움 논문집 Proceedings of Symposia on Plant Biotechnology
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• pp.19-49
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• 1987

Recent development of recombinant DNA techniques such as gene cloning and DNA sequencing has led to understanding of genetic information coded on plant genes and their application to crop improvements. Nuclear genes so far isolated and characterized at the molecular level from various plants are those involved mainly in photosynthesis, nitrogen fixation, seed development and defensive responses to environmental stresses. Most of plant genes contain intervening sequences (introns) flanked with GT and AG, as it typical of animal genes. The 5' flanking regions of plant gene revealed the presence of promoter elements such as TATAAA and CCAAT, which have been identified at animal genes to be involved in transcrip- tion initiation. The 3' untranslated regions include a sequence similar to AATAAA whcih functions as a polyadenylation signal in other eukaryotic genes. Furthermore, enhancer-type sequences were found at the 5' flanking regions of various plant genes. This indicates that the structure of plant genes is very similar to animal genes and mechanisms governing the synthesis and processing of mRNAs may be identical in higher eukaryotes. However, genes expression studies involving transformation revealed their differ ences within plants and between plant and animal systems.

• Journal of Forest and Environmental Science
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• 제28권4호
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• pp.278-281
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• 2012

Comparative sequence analyses were conducted on complete mtDNA sequences from four small mammal species in Korea and revealed the presence of 30 well conserved sequences in various regions of the complete mtDNA sequences. The conserved sequences were found in 9 regions in protein coding genes, 10 regions in tRNA genes, 10 in rRNA genes, one region in replication origin and 2 regions in D loop. They could be used to design primers for amplifying complete mtDNA sequences of small mammals.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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• pp.571-574
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• 2005

In this paper, we propose an efficient image segmentation technique for large-sized monochrome images using a hybrid approach which combines threshold and region-based techniques. First, an image is partitioned into fixed-size blocks and for each block the representative intensity is determined by averaging pixel intensities within the block. Next, the neighborhood blocks that have similar characteristics with respect to a specific threshold are merged in order to form candidate regions. Finally, those candidate regions are refined to get final target object regions by merging regions considering the spatial locality and certain criteria. We have performed experiments on images selected from various domains and showed that our technique was able to extract target object regions appropriately from most images.

• 천문학회보
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• 제39권2호
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• pp.60.2-60.2
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• 2014

Hierarchical structure of star-forming regions is widespread and may be characteristic of all star formation. We studied the hierarchical structure of star-forming regions in the Local Group galaxies (M31, M33, Phoenix, Pegasus, Sextans A, Sextans B, WLM). The star-forming regions were selected from Galaxy Evolution Explorer (GALEX) far-UV imaging in various detection thresholds for investigating hierarchical structure. We examined the spatial distribution of the hot massive stars within star-forming regions from Hubble Space Telescope (HST) multi-band photometry. Small compact groups arranged within large complexes. The cumulative mass distribution follows a power law. The results allow us to understand the hierarchical structure of star formation and recent evolution of the Local Group galaxies.

• Ocean and Polar Research
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• 제35권4호
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• pp.351-353
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• 2013

Until recently, Pacific equatorial tropical island states were subject of only very limited interest by scientists, government officials, industry and policy makers of Korea. And, comprehensive information and data on these island regions is not very detailed to help better understand their social backgrounds as well as their natural environment. However, these island regions are now in the middle of diplomatic tug-of-war among super powers as well as becoming nucleus of various science-based ocean issues including marine biodiversity, shifting ecosystem, global environmental change including sea level rise and ocean acidification, fisheries, etc. Therefore, rising political and scientific importance of these areas call for better understanding of these regions, in social aspects as well as natural scientific knowledge of the region. To be provocatively prepared to more actively role in these regions, "A study on Establishing Research Infrastructures in the Tropical Pacific" has been supported during 2012-2013 as a mission-oriented in-house project of the KIOST. This project aims to provide various research infrastructure for Pacific island states, to reinforce cooperation with these nations, and to enhance Korea's national prestige. This special issue contains 10 research articles based on the studies conducted in 2012~2013.