• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2008.10a
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• pp.66-69
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• 2008

As a mobility support for IP have studied, Internet Engineering Task Force(ITEF) standardized the mobile IPv6 protocol. When a mobile node moves between networks, MIPv6 maintains connectivity to network and supports seamless communication, and these processes are called a Handover. IEEE 802.21 standardized MIH(Media Independent Handover) for seamless Handover. MIH used three services for Handover between low layer and upper layer. In this paper, we designed two modes on existing MIH for seamless Handover. We implemented a dual-interface mobile host(MH) model in network simulation2 (ns2) to evaluate how it performs in comparison with single-interface MH.

• Journal of Life Science
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• v.15 no.3 s.70
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• pp.359-364
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• 2005

Spatial autocorrelation was applied to microgeographic variations of Sasa borealis populations in Korea. Separate counts of each type of join (combination of genotypes at a single locus) for each allele, and for each distance class of separation, were tested for significant deviation from random expectations by calculating the Standard Normal Deviation. Moran's I was significantly different from the expected value in 25 of 150 cases $(16.7\%)$. Seven of these values $(4.7\%)$ were negative, indicating genetic dissimilarity among pairs of individuals in the ten distance classes. Populations of S. borealis are small in Korea, and are distributed with occasional cutting of seed-bearing stems used for sieves. Thus, artificial disturbance may contribute to the fact that the S. borealis population of Jirisan is unusual in lacking spatial genetic structure.

• Korean Journal of Ichthyology
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• v.33 no.3
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• pp.196-201
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• 2021

The Indo-West Pacific pipefish, Hippichthys penicillus was newly recorded from Korean waters based on a single specimen (124.5 mm SL) collected from a lower reach of creek of the Namhaedo Island flowing into Dongdae Bay. It is separable from congeners in having a longer snout and unique configuration of principle body ridges including discontinuous superior trunk and tail ridges and straight lateral trunk ridge ending near anus. A new Korean name, "Huin-jeom-sil-go-gi", is proposed for the species.

• Proceedings of the Korea Information Processing Society Conference
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• 2010.04a
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• pp.143-145
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• 2010

유비쿼터스 컴퓨팅이란 언제 어디서나 사용자가 원하는 서비스를 제공받을 수 있는 컴퓨팅 환경을 말한다. 최근 네트워크와 컴퓨팅 기술이 발달하고 서비스에 대한 수요가 늘어남에 따라 유비쿼터스 컴퓨팅에 대한 관심도 증가하고 있으며 지속적인 연구가 이루어지고 있다. 그 동안 이루어진 많은 연구들을 통해 유비쿼터스 컴퓨팅 환경을 구축하기 위한 기반기술에 큰 발전이 있었다면, 최근에는 실제 유비쿼터스 환경에서 사용자에게 제공되는 서비스 컨텐츠의 효과적인 개발 및 확대에 대한 관심이 높아지고 있다. 모든 개체들이 네트워크로 연결되는 유비쿼터스 컴퓨팅 환경에서는 대부분의 사용자 컨텐츠가 네트워크를 통해 호출할 수 있는 원격 서비스의 형태로 제공된다. 또한 이러한 서비스들은 웹 서비스나 OpenAPI 등 다양한 형태로 존재하므로 이러한 원격 서비스들이 효과적으로 융합되고 재생산 될 수 있어야 한다. 따라서 본 논문에서는 기존에 존재하는 형태의 원격 서비스들을 융합하여 새로운 서비스를 개발하기 위한 기법 및 도구를 제시한다. 이를 위해 본 논문에서는 유비쿼터스 컴퓨팅 환경에서 제공되는 서비스 형태를 U-Service로 정의하며, U-Service를 효과적으로 명세하고 융합할 수 있는 기법 및 도구를 제시한다.

• Journal of the Korea Society of Computer and Information
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• v.14 no.6
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• pp.125-134
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• 2009

A biological data acquisition based on web has emerged as a powerful tool for allowing scientists to interactively view entries form different databases, and to navigate from one database to another molecular-biology database links. In this paper, the biological conceptual model is constructed hybrid biological data model to represent interesting entities in the data sources to applying navigation rule property for each biological data source based on four biological data integrating layers to control biological data. When some user's requests for application service are occurred, we can get the data from database and data source via web service. In this paper, we propose a query processing model and execution structure based on integrating data layers that can search information on biological data sources.

• Annual Conference on Human and Language Technology
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• 2021.10a
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• pp.259-263
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• 2021

상호참조해결은 주어진 문서에서 상호참조해결 대상이 되는 멘션(mention)을 식별하고, 동일한 개체(entity)를 의미하는 멘션들을 찾아 그룹화하는 자연어처리 태스크이다. 최근 상호참조해결에서는 BERT를 이용하여 단어의 문맥 표현을 얻은 후, 멘션 탐지와 상호참조해결을 동시에 진행하는 end-to-end 모델이 주로 연구되었으나, 512 토큰 이상의 긴 문서를 처리하기 위해서는 512 토큰 이하로 문서를 분할하여 처리하기 때문에 길이가 긴 문서에 대해서는 상호참조해결 성능이 낮아지는 문제가 있다. 본 논문에서는 512 토큰 이상의 긴 문서를 위한 BERT 기반의 end-to-end 상호참조해결 모델을 제안한다. 본 모델은 긴 문서를 512 이하의 토큰으로 쪼개어 기존의 BERT에서 단어의 1차 문맥 표현을 얻은 후, 이들을 다시 연결하여 긴 문서의 Global Positional Encoding 또는 Embedding 값을 더한 후 Global BERT layer를 거쳐 단어의 최종 문맥 표현을 얻은 후, end-to-end 상호참조해결 모델을 적용한다. 실험 결과, 본 논문에서 제안한 모델이 기존 모델과 유사한 성능을 보이면서(테스트 셋에서 0.16% 성능 향상), GPU 메모리 사용량은 1.4배 감소하고 속도는 2.1배 향상되었다.

• 한국해양학회지
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• v.30 no.5
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• pp.413-425
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• 1995

Abundances and bacterivory of heterotrophic and mixotrophic nanoflagellates were investigated fourtimes between October 1993 and March 1995 in an estuarine system of the Mankyung and Dongjin rivers to understand distributions of nanoflagellates and ecological significance of bacterivory of nanoflagellates. Bacterivory of nanoflagellates were measured with fluorescently labeled bacteria (FLB). Heterotrophic and autotrophic flagellates showed a rage of 438-4,159 cells ml/SUP -1/ (mean of 2,145 cells ml/SUP -1/, n=20) and 971- 4,935 cells ml/SUP -1/ (mean of 2,2226 cells ml/SUP -1/, n-20), respectively. These two groups of nanoflagellates generally showed similar distributions of abundance. Abundances of heterotrophic nanoflagellates, known as major grazers of bacteria, and those of autotrophic nanoflagellates with chloroplasts showed statistically significant correlations with bacterial abundance (respectively, r$^2$=0.51 and r $^2$=0.47, p>0.05). Mixotrophic nanoflagellates seemed to comprise at least 4-23% of autotrophic nanoflagellate populations. Individual predation rates of heterotrophic nanoflagellates ranged from 2.2 to 14.2 bacteria flagellate/SUP -1/ h/SUP -1/ (mean of 4.9 bacteria flagellate/SUP -1/h/SUP -1/, n=16), and those of mixotrophic nanoflagellates from 1.6 to 9.7 bacteria flagellate/SUP -1/ h/SUP-1/ (mean of 3.7 bacteria flagellate /SUP -1/ h/SUP -1/, n=16). Bacterivory by mixotrophic nanoflagellates comprised from 30 to 69% of total nanoflagellates grazing on bacteria, indicating the significant role of mixotrophic nanoflagellates as grazers on bacteria in the study area. The ratios of grazing rates on bacteria to bacterial secondary production ranged widely from 0.06 to 1.23. In June, when abundances of total nanoflagellates were low, removal of bacteria by bacterivory of nanoflagellates was also a small fraction (0.08${\pm}$ 0.01, n=4) of bacterial production. In other seasons, nanoflagellates usually grazed on bacteria in significant fraction (0.06${\pm}$0.37, n=9) of bacterial production. Both heterotrophic and mixotrophic nanoflagellates appear to be major grazers on bacteria, and might transfer bacterial secondary production to higher trophic level in an estuarine system of the Mankyung and Dongjin rivers.

• Korean Journal of Ecology and Environment
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• v.44 no.2
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• pp.203-213
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• 2011

Agriculture modern environments can vary due to factors such as land consolidation and ditch enhancement projects. But, these improvements projects can include cover-ing-up of irrigation ditches with concrete, increasing the drop between paddy field and drainage ditches, which might decrease the abundance and diversity of fish fauna around paddy fields. In this study, for the management of agrobiodiversity on fish in paddy fields, we installed a small-scale fishways between paddy fields and drainage ditches, and evaluated the effects on the eco-connection of the paddy fields, ditches and stream. Five fish species were recovered at the drainage ditches. The species exhibited characteristics spawning and growth based on the paddy field. The results indicate that the five fish species could ascend the paddy fields through the small-scale fishways. There are no difference of species numbers at ditches of environment-friendly agriculture paddy fields (A) and good agricultural practices (B) region, but individual numbers were higher at the B region. This result could be interpreted as indicating that ditch diversity was affected by positional properties rather than farming practices because the water flow and connection to adjacent stream of B region were better than A region. After ascertaining the fish species capable of ascending in a pre-survey of the drainage ditches, we set up small-scale fishways at the drop between paddy fields and drainage ditches. Three species of fish (Aphyocypris chinensis, Misgurnus anguillicaudatus, M. mizolepis) arrived at the paddy fields via small-scale fishways. The main movement time was from 18:00~24:00 and 00:00~06:00, indicating a preference for the night time period rather than the day period for migration. Concentrating the operation time from night to dawn seems prudent for effective management of small-scale fishways.

• Applied Microscopy
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• v.41 no.1
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• pp.55-60
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• 2011

Reduced plants of Spirodela polyrhiza consisting only of fronds, stalks and roots form turions during dormancy. In development, mature fronds produce offspring fronds by vegetative reproduction, and turions arise laterally from the mother frond before dormancy. The turion primordium is derived from the frond, while the frond primordium forms within the turion tissue. In the present study, cellular features, especially those of the plastids, of the above four tissue types have been examined and compared using electron microscopy. Proplastids, found to be numerous in the frond and turion primordia, differentiated into chloroplasts rapidly upon growth. The proplastids were small and the thylakoidal membrane system was rudimentary, howerver the chloroplasts exhibited variation by cell type. Chloroplasts were found within cells of the frond, stalk and root tissue. The thylakoidal membrane system, which formed grana stacks, was moderately developed within frond chloroplasts, while only a few were present in those of the stalk and root cortical cells. One to two starch grains were accumulated within frond chloroplasts, but little to none were found in stalk and root cortical chloroplasts. Contrary to other types of root chloroplasts, those found in the root cap cells developed chloroplasts similar to the frond type. Unlike proplastids of the turion primordia, numerous large amyloplasts occupied most of the turion cell volume. Moreover, the turion cell produced quite large starch grain (s) within the amyloplasts. Accumulation of the starch grains continued until they occupied the most of the stroma and in some cases, individual starch grains reached up to $9.0{\mu}m$ in length. None to little, if any, thylakoidal or internal membranous systems were seldom detected in these amyloplasts. Although the degree of cellular and tissue differentiation was rather minimal within their reduced body, the functional differentiation of Spirodela polyrhiza was very efficient, as is the case in other advanced species.

• Korean Journal of Environment and Ecology
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• v.34 no.2
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• pp.170-178
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• 2020

There are few landscape ecological analyses of Khingan fir (Abies nephrolepis) and other habitats of the sub-alpine zone in South Korea. In this study, we tried to quantitatively interpret and assess the habitat characteristics by analyzing 15 landscape indices according to the differences in tree layer coverage, in the Khingan fir habitat growing naturally in the sub-alpine zone of Seoraksan National Park. It was difficult to identify the tendency of landscape ecology to increase and decrease the tree layer coverage in the study site, which was the entire Khingan fir habitat in Seoraksan National Park. However, the Khingan fir habitat was found to be generally low in coverage, and population density as the tree layer coverage of less than 50 percent accounts for 85 percent of the total habitat. Moreover, the Khingan fir habitat in the 10 to 50 percent range was fragmented into a total of 286 patches, making it relatively less connected to the habitat. The total edge length and edge density, which could determine the edge effect of the main part according to the physical form, were the highest in the habitat of 26 to 50 percent coverage, indicating a relatively high impact from outside than habitats of other coverages. The shape with the tree layer coverage of between 10 and 50 percent was more complex even with patches of the same size, and it is believed that these characteristics make it more susceptible to habitat fragmentation and external confounding. We expect that the results of this study can be useful for time series analysis of spatial expansion or reduction of the Khingan fir habitat in Seoraksan National Park and provide the reference data for the morphological change and movement of patches and the connectivity and break-off between forests.