• Journal of the Korean Geographical Society
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• v.39 no.4
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• pp.528-543
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• 2004

The biogeographical approach on the species composition, distributional range, and life form of native Korean conifers suggests that the Korean Peninsula harbors 4 families 10 genera 30 species. Early-evolved conifers maintain high species diversity and broad distribution. During the glacial periods, the ranges of cold-tolerant conifers expanded, on the other hand, those of warmth-tolerant ones reduced. Presence of endemic subalpine conifers might be the result of long-term isolation of conifers on high mountains. Horizontal and vertical ranges of native Korean conifers are classified into alpine, subalpine, montane, coastal, insular and disjunctive types, and then subdivided into twelve sub-types. Typical life form of native Korean conifers is evergreen tree, blooms in spring, and fruits ripe in autumn or following autumn. Oval and elliptical seeds with wing might be beneficial for their dispersal. Further works on the migration, dispersal, genetics, ecology of native Korean conifers are required for the better understanding of the biogeography of conifers.

• Korean Journal of Food Science and Technology
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• v.22 no.1
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• pp.7-12
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• 1990

The effect of $Fe^{2+}$ and myoglobin on the oxidative stability of triglyceride molecular species was investigated at $25^{\circ}C$. The molecular species of soybean oil triglycerides were analyzed by capillary column gas chromatography and electron impact ionization mass spectrometry utilizing selected ion monitoring. When $Fe^{2+}$ and myoglobin were added to soybean oil triglycerides, the oxidative stability of each molecular species of triglycerides appeared to decrease in proportion to the increase in the number of double bonds present in the acyl residues, and it was affected by degree of unsaturation of fatty acid when the total degree of unsaturation of triglyceride was the same. But the length of the saturated acyl chain had no influence on the stabilization of unsaturated fatty acid present in the same glyceride when prooxidants were added.

• Korean Journal of Environmental Biology
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• v.39 no.2
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• pp.137-146
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• 2021

We aimed to investigate the macromoth diversity and species composition between two forest types; a small and fragmented agroecosystem(SFA) and a large and continuous forest ecosystem(LCF). We sampled moths twice(in June and August) using ultraviolet light traps employed in eight regions from 2018 to 2019. The results showed a significant difference between the two ecosystems; species richness, abundance and species diversity index (H') were significantly higher in LCF than in SFA. Beta diversity using Chao-Sorensen Raw abundance showed that moth community in SFA was different from that in LCF. The two components of beta diversity showed that the turnover rate was higher in LCF while nestedness was higher in SFA.

• Proceedings of the Korean Information Science Society Conference
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• 2005.11a
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• pp.193-195
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• 2005

최근 유비쿼터스 컴퓨팅의 핵심 기술인 센서 네트워크 기술이 활발하게 연구되고 있는 실정이다. 이에 다양한 센서 노드 기술이 개발되면서 각기 다른 종류의 센서 노드로 구성된 이기종의 센서 네트워크의 연동에 관한 연구가 활발히 진행되고 있다. 기존에 제안된 이기종 센서 네트워크의 통합, 관리를 위한 기술은 구현이 복잡하고, 각각의 노드에 않은 연산 부하가 발생하여, 기존의 시스템을 사용하지 못해 비효율적이다. 본 연구에서 제안하는 임베디드 시스템은 Base Station 역할로 동작하여 전체 센서 네트워크의 상위에 정의되어지는 네트워크를 구성하며, 각기 다른 센서 네트워크의 데이터를 연동함으로서 노드의 연산부하를 줄이고, 기존에 구현된 센서 네트워크와 시스템을 사용함으로서 구현의 복잡성을 줄이며 효율성은 높이는 것이 가능하다. 본 연구에서는 이기종 센서 네트워크의 통합과 관리를 위해 위와 같은 이점을 갖는 임베디드 시스템을 설계하고 구현하고자 한다.

• Proceedings of the Korea Information Processing Society Conference
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• 2005.11a
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• pp.1117-1120
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• 2005

최근 유비쿼터스 컴퓨팅의 핵심 기술인 센서 네트워크 기술이 활발하게 연구되고 있는 실정이다. 이에 다양한 센서 노드 기술이 개발되면서 각기 다른 종류의 센서 노드로 구성된 이기종의 센서 네트워크의 연동에 관한 연구가 활발히 진행되고 있다. 기존에 제안된 이기종 센서 네트워크의 통합, 관리를 위한 기술은 구현이 복잡하고, 각각의 노드에 많은 연산 부하가 발생하며, 기존의 시스템을 사용하지 못해 비효율적이다. 본 연구에서 제안하는 Overlay Sensor Network는 전체 센서 네트워크의 상위에 정의되어지는 네트워크로, Overlay Sensor Network를 구성하는 Base Station 노드가 각기 다른 센서 네트워크의 데이터를 연동함으로서 노드의 연산 부하를 줄이고, 기존에 구현된 센서 네트워크와 시스템을 사용함으로서 구현의 복잡성을 줄이며 효율성은 높이는 것이 가능하다. 본 연구에서는 이기종 센서 네트워크의 통합과 관리를 위한 Overlay Sensor Network를 제안하고, 그에 따른 시스템을 설계하고 구현하고자 한다.

• Information and Communications Magazine
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• v.29 no.2
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• pp.68-76
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• 2012

최근의 무선 통신은 LTE, WiMAX, 무선랜 등이 공존하는 이기종 네트워크와 멀티 인터페이스를 탑재한 멀티 모드 단말로 인하여 큰 발전을 이루고 있다. 이기종 네트워크는 다양한 무선 접속 기술을 갖는 통합 네트워크로 상황에 맞는 최적의 무선 네트워크를 이용하여 사용자에게 최상의 통신 서비스를 제공할 수 있다. 본 논문에서는 이기종 네트워크의 구성과 연동 레벨 및 구조를 살펴본다. 또한 이기종 네트워크에서 발생하는 주요 이슈인 이동성 제공, 무선 자원 관리, 멀티미디어 서비스 제공에 대해서 분석하고 최신 연구 및 표준화 통향을 소개한다.

• Korean Journal of Environmental Biology
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• v.40 no.4
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• pp.464-476
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• 2022

In recent years, macroalgal bloom occurs frequently in coastal oceans worldwide. It might be attributed to accelerating climate change. "Green tide" events caused by proliferation of green macroalgae (Ulva spp.) not only damage the local economy, but also harm coastal environments. These nuisance events have become common across several coastal regions of continents. In Korea, green tide incidences are readily seen throughout the year along the coastlines of Jeju Island, particularly the northeastern coast, since the 2000s. Ulva species are notorious to be difficult for morphology-based species identification due to their high degrees of phenotypic plasticity. In this study, to investigate temporal variation in Ulva community structure on Jeju Island between 2015 and 2020, chloroplast barcode tufA gene was sequenced and phylogenetically analyzed for 152 specimens from 24 sites. We found that Ulva ohnoi and Ulva pertusa known to be originated from subtropical regions were the most predominant all year round, suggesting that these two species contributed the most to local green tides in this region. While U. pertusa was relatively stable in frequency during 2015 to 2020, U. ohnoi increased 16% in frequency in 2020 (36.84%), which might be associated with rising sea surface temperature from which U. ohnoi could benefit. Two species (Ulva flexuosa, Ulva procera) of origins of Europe should be continuously monitored. The findings of this study provide valuable information and molecular genetic data of genus Ulva occurring in southern coasts of Korea, which will help mitigate negative influences of green tide events on Korea coast.

• Korean journal of applied entomology
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• v.52 no.3
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• pp.205-213
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• 2013

Forest fires disturb communities of forest-dwelling insects by killing or dispersal. Species diversity, species composition, and functional guilds of ant communities will be changed following forest fires. A survey of ants was conducted to find changes in ant communities after a large fire occurred in Goseong within Gwangwon province in South Korea in 1996. In total, 1,308 ants representing 16 species were collected; 696 ants representing 15 species were collected at the burned site, and 612 ants representing 13 species were collected at the unburned site. Contrary to the general expectation which predicts a decrease of diversity and abundance after fire, abundance, species diversity, species composition, and functional guilds of ant communities did not differ between the burned site and the unburned site. Furthermore, estimated species richness was significantly higher at the burned site than at the unburned site. However, monthly occurrences of ants (abundant species and pooled) were different between the burned site and the unburned site. Ants were more abundant at the burned sites than the unburned site just after the fire (May 1996). However, they were more abundant at the unburned site than the burned site in autumn (September and October 1996). This phenomenon might be caused by environmental change (e.g., decrease of soil moisture). In conclusion, the fire did not significantly change ant fauna, as fire in spring cannot destroy ant colonies that are wintering in deep soils.

• Proceedings of the Korean Society of Crop Science Conference
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• 1977.05a
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• pp.18-18
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• 1977

• Korean Journal of Plant Resources
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• v.27 no.1
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• pp.35-42
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• 2014

Correlation and similarity of garlic cultivars was analyzed by measuring the composition of twenty amino acids contents in the bulb and callus from twelve garlic cultivars which were collected from Korea and foreign countries. Arginine and asparagine occupied more than 78% of total amino acids both in bulb and callus followed by glutamic acid, lysine, aspartic acid, valine, glycine, histidine and ornithine in order. Based on correlation coefficients of amino acid composition in the bulb, twelve garlic cultivars were classified into three major groups. Danyang, Euiseong, Seosan, Jeju, Mongol and Turkey cultivars belong to group-I, Namdo, China, Mexico and Nepal cultivars are in group-II, and group-III includes Philippine and Daeseo cultivars. Based on amino acid composition in callus, group-I includes Mongol, Euiseong, Danyang and Seosan cultivars, group-II includes Jeju, Daeseo, China and Namdo cultivars, group-III includes Napal, Mexico, Philippine and Turkey cultivars. Composition of amino acid contained in both callus and bulb is a clear standard to identify northern-type garlic cultivars. Especially the composition of amino acids in callus is more distinctive standard of classification between northern and southern type garlic cultivars than that in bulbs.