• 천문학회보
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• 제45권1호
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• pp.57.2-57.2
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• 2020

We observed the Class I protostar TMC-1A in polarized dust emission at 1.3 mm at a spatial resolution of ~40 au using ALMA. Previous observations revealed a disk (r~100 au), surrounded by an infalling envelope, and a CO outflow going in the north-south direction in TMC-1A. Our observations detected polarized dust emission in a central region (r~50 au) and ~100 au north and south of the central protostar. The former polarization is likely due to self-scattering because of the polarization direction along the disk minor axis, the polarization fraction independent of Stokes I, and a high optical thickness. The latter polarization is roughly in the outflow region. The position and direction, particularly in the north, imply multiple possible mechanisms: magnetically or mechanically aligned dust grains in the outflow or in an accretion flow.

• 대한바이러스학회지
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• 제30권2호
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• pp.131-139
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• 2000

Bovine leukemia virus (BLV) is an etiological agent of chronic diseases in cows worldwide. The BLV is one of retroviruses that contain a multi-functional enzyme, reverse transcriptase produced from the pol gene in its genome. We have sequenced some regions in the pol gene of BLV proviruses found in the Southern province of Korea from samples that turned out to be BL V positives by a PCR analysis. On the 5' side of the BLV pol gene (polymerase region), it was found that there were four leucines located at every 7 amino acids. They can form a leucine zipper motif that was not same as the pol gene of Japanese BLV isolate. The sequencing result of the proviral pol gene in Korean-type BLV also revealed some mutations leading to amino acid changes such as $CCT(Pro){\to}CTC(Leu)$, $AAT(Asn){\to}AAA(Lys)$, and non-sensible variations i.e., $TCT(Ser){\to}TCC(Ser)$, $ATT(Ile){\to}ATC(I1e)$ and $ACG(Thr){\to}ACA(Thr)$. On the 3' side of the pol gene (integrase region), some nucleotide sequences were mutated and led to amino acid changes. Among them, a mutation, $GAA(Glu){\to}GAC(Asp)$ occurred in many Korean-type BLV proviruses was very interesting because the amino acid was regarded as one of the most conserved amino acids in the retroviral integrase. It was also notable that the mutation on any leucine residue did not occur, in spite of its frequent appearance.

• 한국지형학회지
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• 제24권3호
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• pp.133-147
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• 2017

This study investigated the cases of relative location, especially focused on the geomorphological situation, for the conceptualization of the location knowledge. In order to perform this study, first of all, I approached meaning of location. In this study I used the terms 'site' and 'situation'. 'Site' as used here means the location of a given place with its local internal features or resources. 'Situation' refers to the location of place as related to other places. As to location, no place exists in isolation. Therefore, it is necessary to look beyond the internal nature of the area itself to perceive its external relations with other areas. The examples of geomorphological situation were focused on the scale linkage of the examples, the interaction between elements of earth surface processes, and the method of comparative region. The regions of examples were the landscape of Mt. Hymalaya to Bengal deep sea fan, the climatical difference of continental east and west, the landscape of Mt. Geum & Sangju beach, the landscape of the south and north face of Mt. Mai., Hamjibaakgol asymmetrical valley, and the landscape of inland sea and outer sea type island.

• Journal of Contemporary Eastern Asia
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• 제18권1호
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• pp.1-6
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• 2019

During the Obama administration, America made a shift in its foreign policies to re-focus on Asia. The strategy, known as 'Pivot to Asia', was used to contain a rising China. In this editorial note, I appropriate the geopolitical term to call for a scholarly refocus on Asia (and the broader Asia Pacific region). JCEA started as an area journal. While it has become more technology-focused and less geographically-bounded in its coverage of topics, the journal recognizes the centrality of the region's political economy and technological forces in setting (and upsetting) global norms and rules. The Asia Pacific contains the world's freest economies as well as the most oppressive regimes. It breeds both technology giants and laggards. As new geopolitical tensions loom, it is where the digital iron curtain is drawn, and where the vice and virtue of innovations debated. Social scientists in the English world, who lend extensively on European and American cases, can benefit from studying the Asia Pacific by testing whether and how local experience conforms to or confronts with universal theories. Very likely, western-centric norms and models become morphed and entangled in the grounded local particularity, reflecting many shades of this diverse place. In my arguments below, I highlight the Asia Pacific as a site of contradiction, as well as a site of contention and negotiation. My emphasis is that regional particularity holds the key to answer concurrent debates in the West concerning governance and accountability in the digital age.

• 한국지구과학회지
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• 제33권5호
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• pp.422-433
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• 2012

The purpose of this study is to investigate the characteristic changes of the Changma season in the 2000s. To accomplish this goal, we have used daily rainfall data collected over nearly 40 years (1971 to 2010). The average summer precipitation data including the Changma season were collected from 16 weather stations that are placed across the three major regions (i.e. central region, southern region, and Jeju region) as Korea Meteorological Administration divided. These precipitation data were analyzed to find out characteristic changes of the Changma season. Results of the precipitation data comparison among the major regions that, monthly average precipitation in the central region was the highest in July; its precipitation tended to increase from May to September. In the southern region, the precipitation amount was lowest in June and tended to increase in May, September, and August. In the Jeju region, the precipitation has been the highest in June and July for the past 30 years, whereas September has been highest month in the last 10 years. The precipitation amount in the Jeju region decreased both in June and July, whereas it tended to grow in May, August and September. A correlation coefficient formula by Karl Pearson has been used to find out correlations between the Changma season and the precipitation of the major regions in 2000s and normal years. It was found that the correlation coefficient has decreased from 0.723 to 0.524 in the 2000s (2001 to 2010) compared to normal years (1971 to 2000).

• 대한교통학회지
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• 제12권1호
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• pp.43-54
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• 1994

The major concern of this paper is to investigate the properties of a stochastic equilibrium for each model system in terms of a consumer welfare measure. The primary assumption for this study is that a trip-maker would choose the trip from his origin zone which maximizes his personal welfare. This assumption, finally, leads to a singly constrained gravity model. The consumer welfare measure is derived from the concept of expected welfare of randomly sampled trip-makers. Each of the four different models considered in this paper is differentiated depending on the complexity of its model or the definition of its travel function. In this study, three different regions are chosen for the purpose of taking into account the effects of different zone-systems on the properties of a stochastic equilibrium : (i) Archerville region (5 zone) ; (ii) San Francisco Bay regions (30 zones) ; (iii) Houston, TX region (199 zones). It is concluded that almost identical, "global" consumer welfare values can be obtained in some cases of the gravity-type trip distribution models based on a stochastic equilibrium.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 신호처리소사이어티 추계학술대회 논문집
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• pp.263-266
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• 2003

In this paper, we propose a new progressive image transmission system including the image coding scheme that efficiently uses the relationship between the properties of a spatial image and its wavelet transform. Firstly, an original image is decomposed into several layers by the wavelet transform, and simultaneously decomposed into 2"x2" blocks. Each image is classified into two image types according to the standard deviations of its blocks. And then each block is categorized into two regions by different thresholds according to the image types, i.e., significant activity region (SAR) and insignificant activity region (IAR). Simulation results show that the proposed coding method has better performance than the EZW and SPIHT in terms of image quality and transmitted bit-rate. In addition, it can be applied to the applications requiring the progressive image transmission.nsmission.

• 한국군사과학기술학회지
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• 제10권3호
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• pp.25-33
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• 2007

In this paper, I propose a method which can enhance the visual quality of IRST images based on a loaded location in ship and an AOS. The IRST adjusts an AOS to detect targets with various altitudes because of its narrow vertical field of view and offers various functions to enhance images with its low contrast. In the proposed method, images are divided into two regions of sea and sky on the basis of the horizon after establishing relation between an AOS and a horizon location within an image. As a result, image enhancement of the proposed method is performed adaptively according to the divided region while that of conventional method is performed for entire image without the region division. Simulation results show that the proposed method represents higher visibility compared with conventional one.

• 한국토양비료학회지
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• 제35권1호
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• pp.12-26
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• 2002

근류형성에 의한 생물학적 질소고정기능을 갖는 여러종의 근류균을 대상으로 분자생물학적 계통 분류의 기초자료를 얻기 위하여 Azorhizobium, Bradyrhizobium, Mesorhizobium, Rhizobium, Sinorhizobium 속의 33 균주에 대한 ITS 영역의 염기서열을 이용한 계통 분류가 이루어 졌다. 이들 균주중 대부분의 균주는 한 종류의 ITS 영역을 가지는 반면, 일부균주는 2개의 서로 다른 ITS 염기서열을 가지는 것으로 나타났다. 실험에 이용된 모든 균주들간의 ITS 영역의 염기서열 상동성은 28 - 95%로 매우 변이폭가 컸으며, 이들 염기서열의 계통 분석에 의하면 4가지 그룹으로 구분되었다. Sinorhizobium 속의 모든 균주 및 Rhizobium giardinii 는 그룹 I으로 구분되었다 그룹 II는 R. giardinii를 제외한 모든 Rhizibium 속의 균주를 포함하고 있으며, 계통수의 topology는 매우 불안정한 것으로 나타났다. 특히, R. radiobacter와 R. rubi는 계통분류학적 위치가 불명확한 것으로 나타났다. Bradyrhizobium 속의 균주는 Azorhizobium caulinodans 와 함께 그룹 III로 구분되었고, 그룹 IV는 Mesorhizobium 속의 균주로 이루어 ㅈ다. 특히, Mesorhizobium 속균주의 ITS 영역의 염기서열 상동성이 높게 나타났다.

• Archives of Pharmacal Research
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• 제19권6호
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• pp.497-501
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• 1996

A gene coding for triosephosphate isomerase (TPI) from a rat skeletal muscle cDNA library was cloned and its nucleotide sequence was determined. The 1, 348-bp cDNA clone contains 24 bp $5^I$ noncoding region, the entire 750 bp coding region corresponding to a protein of 249 amino acids, $547bp 3^I$ noncoding region and part of a poly(A) tail. It also contains a polyadenylation signal, AATAAA, starting from 17 bp upstream of the poly(A) tail. The calculated molecular weight of rat TPI is 27.8 kDa and the net charge is +4. The deduced amino acid sequence from rat TPI CDNA sequence has 93% and 94% homology with that of mouse and human clones, respectively. The amino acids at the residue of Asn12, Lys14, His96, Glu 166, His96, His101, Ala177, Tyr165, Glu13O, Tyr2O9, and Ser212 in catalytic site are completely identical, confirming that the functional residues in TPI proteins are highly conserved throughout evolution. The most profound characteristic of rat TPI enzyme, compared with other TPIs, is that there are five cysteine substitutions at the residue of 21, 27, 159, 195 and 204. A Glu123 instead of Gly was found in rabbit, rhesus, mouse and human sequences. Through the method of RT-PCR, the mRNA transcription level of TPI gene was found to be different among various tissues and was highest in muscle.