• Ocean and Polar Research
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• 제30권1호
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• pp.11-19
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• 2008

Incubation routine and sex role of Streaked Shearwaters Calonectris leucomelas at Sasudo Island, in Jeju, South Korea, were studied during the incubation period, June to August in 2002. Incubation routine in Procellariiformes represents a sequence of alternating shifts taken in turn by female and male in a species-specific pattern. Hence, coordination of individual incubation rhythms between partners is crucial for successful breeding attempt. In Streaked Shearwaters, incubation routine represents a sequence of alternating shifts taken in turn by male and female. The first incubation shift was made by male after female had laid the egg. The mean incubation period was 50.8 days until hatching. Males had spent on average 26.5 days incubating and females 24.3 days accordingly. The mean duration of incubation shifts decreased progressively from 6th and 7th shift to hatching. Overall, males had spent more time incubating than females during the incubation period, but the mean duration of the incubation shift 5.6 days for males and 5.7 days for females did not differ between males and females. There were no effect of the body size of the breeding pair on incubation performance. For males the mean of body weight decreased during the incubation, whereas for females it remained approximately stable. In Streaked Shearwaters, the duration of incubation shift and subsequent foraging trip are related to loss of body weight during the period of fasting. In addition, coordination of individual incubation rhythms affects their incubation behaviour.

• 한국환경복원기술학회지
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• 제7권1호
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• pp.19-29
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• 2004

This study was carried out to understand the bird community and habitat using condition in the Gildong natural ecological park, from April 2001 to March 2002. In this study, 63 species and 2,075 individuals were observed respectively. The dominant species were Paradoxornis webbianus(33.6%), Emberiza elegans 18.5%), Parus major(6.4%), Pica pica(6.0%), and the diversity of the species was 2.511. With migration, the highest number and percentage to the lowest was residents, summer visitors, winter visitors and passage migrants. Among 17 species which bred in the Gildong natural ecological park, hole(H) was 47.1%, canopy(C) was 41.1% and bush(B) was 11.8% in their nesting guilds. In foraging guilds in breeding season was canopy(c) was 45.7%, water(w) was 23.9% and bush(c) was 15.2%, and, in non-breeding season, canopy was 43.5%, water 23.9% and bush 21.7%. For the habitats of the birds in the Gildong natural cological park, reservoir area was used by herons, ducks and sandpiper, wetland area was used by Lanius bucephalus, Paradoxornis webbianus and buntings, grassland area was used by Paradoxornis webbianus and buntings, and forest area was used by Streptopelia orientalis, woodpeckers and tits. The number of species and individuals of birds observed in the Gildong natural ecological park was higher than other urban parks. We suggest that this was attributed to different habitats such as reservoir, wetland, grassland and forest area constructed in the Gildong natural ecological park.

• 한국통신학회논문지
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• 제42권1호
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• pp.64-76
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• 2017

MANET (Mobile Ad hoc Network)에서 라우팅은 네트워크 토폴로지의 동적인 변화에 큰 영향을 받는다. AntHocNet은 집단 개미가 최적 경로를 통해 먹이를 찾아가는 원리를 모방한 집단생태 특성 기반 MANET 라우팅 프로토콜이다. 하지만, AntHocNet은 다른 MANET 라우팅 프로토콜과 달리 단방향 경로만을 지원하여 양방향 통신이 요구되는 다양한 응용 환경에서 사용하기에 많은 제약이 따른다. 또한, AntHocNet은 다중 경로를 통한 확률적 라우팅으로 인해 루핑 문제 (looping problems)를 빈번히 발생시킨다. 본 논문에서는 AntHocNet에서 양방향 경로 수립을 위한 향상된 경로 수립 방안을 제안한다. 또한, 다양한 시나리오별 루핑 문제의 발생 원인을 분석하고 루프 방지를 위한 해결 방안을 제시한다. NS-2 시뮬레이션을 통해 기존 AntHocNet과의 성능을 비교하였으며, 제안 방안이 라우팅 오버헤드, 종단간 지연 시간, 패킷 전달률 측면에서 기존 방안에 비해 우수한 성능을 보임을 확인하였다.

• 한국환경생태학회지
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• 제21권1호
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• pp.47-54
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• 2007

본 연구는 광릉 지역의 활엽수 천연림과 도로 주변에서 서식지 구조와 조류군집의 특성을 파악하기 위해 2005년 10월부터 2006년 8월 사이의 기간 동안 수행되었다. 활엽수 천연림과 도로 지역의 서식지 환경은 매우 큰 차이가 있는 것으로 나타났다. 활엽수 천연림은 대경목의 비율이 높고 상층 임관이 잘 발달해 있는 반면, 도로에서는 소경목이 대부분을 차지하였으며, 상층임관의 발달이 적은 반면 하층식생의 피도가 높았다. 계절별 조사 결과 활엽수 천연림에서는 모두 37종의 조류가 관찰되었으며, 도로에서는 20종이 기록되었다. 4계절에 있어서도 활엽수 천연림 이 도로보다 관찰 종수, 개체수 및 종다양도에 있어서 모두 높은 것으로 나타났다. 또한 길드 구조에 있어서도 활엽수 천연림 지역에서는 수관층 및 수동(나무구멍)에서 먹이와 둥지를 얻는 조류들이 많이 관찰되었으며, 도로에서는 관목이나 지면을 이용하는 조류가 많이 기록되었다. 두 지 역은 인접해 있음에도 불구하고 조류 군집의 특성에 있어서 큰 차이를 보였다. 이러한 차이는 두 지 역 간 서식환경의 차이와 깊은 연관이 있는 것으로 판단된다.

• 전자공학회논문지CI
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• 제47권3호
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• pp.67-75
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• 2010

본 논문에서는 성능향상을 위하여 개체속력 개념을 적용한 박테리아 협동 최적화 방법을 제안한다. 기존의 박테리아 협동 최적화 방법에서는 개체별로 속력이 일정해 모든 개체가 같은 시간에 똑 같은 거리를 움직인다. 이러한 방법은 개체의 적합도가 좋은 개체나 나쁜 개체가 같은 속력으로 움직임으로서 효과적으로 최적 해를 찾아가지 못하는 문제점이 있었다. 이러한 문제점을 개선하고자 개체의 적합도를 이용하여 개체별 등급을 매기고 등급에 따라서 한 번에 이동할 수 있는 거리를 다르게 하는 속력 개념을 적용하였다. 즉 적합도가 낮은 개체는 적합도가 높은 영역으로 빨리 이동하기위하여 속력을 높이고 적합도가 높은 개체는 주변에 최적 해가 있을 가능성이 있으므로 속력을 낮게 유지하였다. 4개의 함수 최적화 문제에 적용해본 결과 속력개념을 적용하지 않은 방법에 대하여 상당한 성능향상이 있음을 보았다. 특히 성능향상을 위하여 기존에 도입했던 등급별 교체방법보다도 더 좋은 성능을 보였다. 이는 박테리아 협동 최적화의 성능을 향상시키기 위한 방법으로 속력개념을 적용하는 것이 매우 유용함을 보여준다.

• 한국환경복원기술학회지
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• 제19권3호
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• pp.103-119
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• 2016

This study aims to assess habitat feature on the large-scale spawning ground of the Boreal Digging Frog Kaloula borealis in Daemyung retarding basin of Daegu, and to analyze the relationships between species abundance and meteorological factors for each habitat. Fifty-seven(57) pitfalls were installed to collect species abundance of 4 survey regions, and high-resolution satellite image, soil sampling equipment, digital topographic map, and GPS were used to develop habitat features such as terrain, soil, vegetation, human disturbance. The analysis shows that the frog is most abundant in sloped region with densely herbaceous cover in southern part of the retarding basin. In the breeding season, lowland regions, where Phragmites communis and P. japonica dominant wetlands and temporary ponds distributed, are heavily concentrated by the species for spawning and foraging. Located in between legally protected Dalsung wetands and lowland regions of the retarding basin, riverine natural levee is ecologically important area as core habitat for Kaloula borealis, and high number of individuals were detected both breeding and non-breeding seasons. Temperate- and pressure-related meteorological elements are selected as statistically significant variables in species abundance of non-breeding season in lowland and highland regions. However, in sloped regions, only a few variables are statistically significant during non-breeding season. Moreover, breeding activities in sloped regions are statistically significant with minimum temperature, grass minimum temperature, dew point temperature, and vapor pressure. Significant meteorological factors with habitat features are effectively applied to establish species conservation strategy of the retarding basin and to construct for avoiding massive road-kills on neighboring roads of the study sites, particularly post-breeding movements from spawning to burrowing areas.

• 한국환경복원기술학회지
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• 제23권4호
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• pp.97-110
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• 2020

This study conducted observations at 72 traffic lights and road signs in Sejong-si, Korea from March to June 2019 in order to analyze nest-site, nest-site characteristics and feeding behavior in Tree sparrow (Passeer montanus) in urban. Feeding behavior during breeding season in 2019 was investigated at 10 Town representing traffic facilities installed on the road located in the center of the city and 10 Riverside Geumgang river's riverside road. We fitted both general linear model and regression model to our field data and estimated the spatial variation of initial date of the first feeding (i.e., being date of breeding) and the total number of caterpillar fed by parents per hour. Our results showed that the frequency of nest building on artificial structures, such as traffic lights, was about 26% higher and about 8 days earlier in the riverside. In particular, the first feeding was significantly faster when the nearest distance between nest to green field as foraging site was shorter whereas there was no significant effect of the number of nest within 50 meters on the first feeding. Number of caterpillars fed by parents was higher in the Riverside than in the Urban, and especially the number in the second brood was sharply decreased in the Urban. As we estimated average amount of caterpillars per hour to 446 traffic safety facilities in Sejong-si, it was estimated that Tree sparrows fed 18,742.8 caterpillars per hour during the breeding season. In this study, we showed that characteristics of nests built in artificial structures and feeding behavior in order to analyze effects of environmental condition in urban on life-history traits during the breeding season. Finally, we discussed the conservation of birds in urban and pest control effects.

• 농촌계획
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• 제15권3호
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• pp.61-79
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• 2009

This study discusses developing ecological trails and route alignment in mountainous rural area. Through a process of ecological resources survey, ecological trails and route alignment has been established. Mainly, by focusing on ecological resources in rural areas, it was indifferent to their own ecological resource and charm to make it unique strengths. Based on survey the results, Natural ecology resources, there were the climate factor, surface, geological, terrain analysis. Furthermore, ecological resources were researched and analyzed the elements of it, distribution of resources, types, location, semantic analysis. The results are expressed on the map and recorded by taking pictures. Plant ecosystem, there were actual vegetation, land use, flora analysis. Wild animal ecosystem, it was checked and recorded on 1/1,000 map partition the emergence of wild birds, the number of species distributed by foraging guild, the emergence of amphibians, reptile, mammals and insect species. The site is chosen as rural theme village in 2007, base on their own rich ecological and landscape resources. Therefore, we carried out ecological trails and route alignment plan in accordance with analyzed the natural ecological resource and after setting up the basic goal, ecological trail has been composed and planting has done and direction.

• Animal Systematics, Evolution and Diversity
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• 제25권3호
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• pp.325-329
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• 2009

Lepomis macrochirus from the family Centrarchidae, commonly known as Bluegill sunfish, is an introduced freshwater fish in Korea that thrives in lakes, ponds, reservoirs and rivers. Since its introduction into Korea in 1969, Lepomis macrochirus has rapidly dispersed out and increased in number almost all over the freshwater ecosystems in Korea. Consequently this species causes a severe ecological problem, threatening native fishes due to its omnivorous foraging behaviors upon fish juveniles and many freshwater invertebrates. To address population genetic structure of L. macrochirus, 74 fish samples from 10 populations were collected and compared for their mitochondrial D-loop control region. As the result we found that the genetic diversity of L. macrochirus is extremely low such as resulting only four haplotypes with a few nucleotide differences among them. Analysis of molecular variance (AMOVA) revealed that the source of population genetic variation is largely retained in the comparisons among individuals within populations, while it is relatively low with slight significance at the highest hierarchical group. This distribution pattern differs from what is expected when biogeography is under the influence of natural geographic barriers such as mountain ranges in Korea. Instead the result is accord with the influential role of random spreading events facilitated by local people for aquaculture and fishing, and subsequent dispersals since its single point of introduction into Korea.

• Journal of Ecology and Environment
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• 제45권4호
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• pp.255-263
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• 2021

Background: Ecosystem service mapping is an important tool for decision-making in landscape planning and natural resource management. Today, pollination service mapping is based on the Lonsdorf model (InVEST software) that determines the availability of nesting and floral resources for each land cover and estimates pollination according to the foraging range of the desired species. However, it is argued that the Lonsdorf model has significant limitations in estimating pollination in a landscape that can affect the results of this model. Results: This paper presents a free software, named PollMap, that does not have the limitations of the Lonsdorf model. PollMap estimates the pollination service according to a modified version of the Lonsdorf model and assumes that only cells within the flight range of bees are important in the pollination mapping. This software is produced for estimating and mapping crop pollination in agricultural landscapes. The main assumption of this software is that in the agricultural landscapes, which are dominated by forest and agriculture ecosystems, forest patches serve only as a nesting habitat for wild bees and the surrounding fields provide floral resources. Conclusion: The present study provided new software for mapping crop pollination in agricultural landscapes that does not have the limitations of the Lonsdorf model. We showed that the use of the Lonsdorf model for pollination mapping requires attention to the limitations of this model, and by removing these limitations, we will need new software to obtain a reliable mapping of pollination in agricultural landscapes.