• Computers and Concrete
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• 제10권3호
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• pp.295-306
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• 2012

Optimum cost design of a simply supported reinforced concrete beam is presented in this paper. In the formulation of the optimum design problem, the height and width of the beam, and reinforcement steel area are treated as design variables. The design constraints are implemented according to ACI 318-08 and studies in the literature. The objective function is taken as the cost of unit length of the beam consisting the cost of concrete, steel and shuttering. The solution of the design problem is obtained using the artificial bee colony algorithm which is one of the recent additions to metaheuristic techniques. The artificial bee colony algorithm is imitated the foraging behaviors of bee swarms. In application of this algorithm to the constraint problem, Deb's constraint handling method is used. Obtained results showed that the optimum value of numerical example is nearly same with the existing values in the literature.

• 한국환경생태학회지
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• 제25권2호
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• pp.132-144
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• 2011

본 연구는 덕유산국립공원의 향적봉지역(A)과 백련사지역(B) 및 안성지역(C)을 대상으로 2010년 4월부터 9월까지 산림환경과 조류군집 특성을 조사하였다. 향적봉지역은 신갈나무 등의 낙엽활엽수림과 주목, 구상나무 등의 아고산대침엽수림과 원추리, 철쭉 등의 초지가 형성되어있고, 백련사지역과 안성지역은 대부분 낙엽활엽수림으로 구성되고 계곡부는 들메나무 군락이 형성되어 있다. 교목의 흉고직경분포는 11~20cm 경급이 가장 많았으며, 30cm이상 대경목 비율은 백련사지역에서 가장 높았고, 향적봉지역이 가장 낮았다. 또한 엽층별 피도량은 향적봉지역은 하층부 피도량이 매우 높았고, 백련사지역은 8~12m의 중층부 피도량이 높았으며, 안성지역은 18m이상 상층부 피도량이 높게 나타났다. 덕유산국립공원에서 조사기간동안 관찰된 조류는 총 53종이었다. 각 지역별 종수와 밀도는 각각 향적봉지역이 25종 45.20 Ind./km, 백련사지역이 50종 58.63 Ind./km, 안성지역 35종 66.89 Ind./km로 백련사지역의 종수가 가장 많았고, 밀도는 안성지역에서 높았다. 우점종은 향적봉지역이 휘파람새를 비롯한 초지와 관목에 서식하는 종들이 우점하였고, 백련사지역과 안성지역은 오목눈이를 비롯한 수관층에 서식하는 종들이 우점하였다. 길드 구조는 모든 지역에서 관목층 영소길드와 채이길드 종이 높게 나타났고, 수동 영소길드와 공중 채이길드 종의 비율이 낮게 나타났다. 이는 흉고직경 30cm이상의 대경목 비율이 낮아 수동 영소길드 종들의 둥지목이 부족한 결과로 생각된다.

• Journal of Ecology and Environment
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• 제38권2호
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• pp.157-162
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• 2015

The physical factors of Argiope bruennichi (Araneae, Araneidae) that influence the stabilimentum decoration on the web, a conspicuous white silk structure reflecting much more ultraviolet light than other spider silks in the web, have been poorly understood. In this study, individual variables involved in decorating the webs with stabilimenta by A. bruennichi were examined. The results revealed that the physical condition of the female A. bruennichi affected the behaviors of the stabilimentum decoration on the web. Among the 82 female spiders building their webs, the 49 female spiders adding upper and lower stabilimenta on their web weighed less, and had a narrower cephalothorax and shorter abdomen than the 33 female spiders that did not use stabilimentum. The heavier females decorated their webs with stabilimentum of greater widths. There were also significant positive relationships between the stabilimentum area and the female spider's cephalothorax width, and between the stabilimentum area and female spider's abdomen length. Taken together, this study suggests that spiders allocate their resources in stabilimentum decoration as a functional response to the spider's physical conditions, and also supports the "prey-attraction hypothesis," which states that the use of stabilimentum increases the foraging success by attracting more prey to the web.

• 헤리티지:역사와 과학
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• 제37권
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• pp.327-348
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• 2004

본 연구에서는 한반도 이남의 지역적 기후 특성을 분석하고, 서식하고 있는 흰개미 (Reticulitermes speratus kyushuensis Morimoto)의 생태적 특성 및 선호도(온도, 습도, 수종)를 실험실에서 확인하였다. 한반도 이남, 특히 남부지역은 흰개미(R. speratus kyushuensis Morimoto)의 서식 및 활동에 최적인 기후지역으로 확인되었다. 부산이 Coptotermes formosanus Shiraki의 야외 분포 북방한계 ($4^{\circ}C$)에 근접되어 있고, 춘천이 Reticulitermes speratus Kolbe의 야외분포 북방한계 ($-4^{\circ}C$)가 한반도를 통과하는 지역으로 확인되었다. 흰개미는 $30^{\circ}C$ (90% RH이상)에서 최대 먹이 섭취율을 보였다. $10^{\circ}C$에서 $30^{\circ}C$(90% RH 이상)까지 약 95%이상의 생존율이 관찰되었지만, $32^{\circ}C$이상에서 사망률이 높아졌다. 또한 52% RH($30^{\circ}C$)와 70% RH($30^{\circ}C$)에서 높은 사망률(100%)이 관찰되었지만 84% RH에서 높은 생존율(97%)을 보였다. 침엽수인 소나무를 먹이로 선호하고 높은 생존율(87%)을 보였지 만 활엽수인 오동나무에서는 낮은 생존율(14%)이 확인되었다. 서울 종묘의 자연수림에서 흰개미의 침입율은 약 34.5%(55개 지점 중 19개 지점, 3년간) 이었다. 침입율은 매년 증가하였지만 발견율은 낮아지고 실종률은 높아지는 경향이 확인되었다. 흰개미 군체 일부는 발견된 목재를 계속 섭취하고, 다른 일부는 새로운 목재를 탐색하는 먹이 찾기 습성을 실험적으로 확인하였다. 종묘의 지표부근에서 흰개미를 관찰할 수 있는 기간은 2001년 4월부터 11월까지이고 최대 활동기는 7월 및 8월인 것으로 야외실험을 통하여 확인하였다. 그리고 동절기(2000년 11월~2001년 3월)에도 지중에서 활동하는 것이 확인되었다. 이상의 결과, 한국 목조문화재를 가해하는 흰개미의 생태적 특성 및 가해 정도에 관한 생물학적 기초 자료를 최초로 제시하였다. 특히 한반도 이남의 기후조건에 따른 흰개미의 활동시기 및 이에 따른 지역적 손상분포를 확인하고 이를 방제할 수 있는 목재 보존제의 성분 특성 및 효과가 확인됨에 따라 향후 생물학적 손상, 특히 흰개미로부터 한국 목조문화재를 예방적으로 보존 관리하기 위한 종합적 방안수립(Integrated Pest Management, IPM)이 가능할 것으로 기대된다. 또한 이러한 연구결과는 흰개미로 발생되는 경제적 손실을 줄일 수 있는 방제학적 기초 자료로 활용될 것으로 기대된다.

• 환경정책연구
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• 제7권3호
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• pp.141-160
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• 2008

본 연구는 속리산 국립공원에서 쌍곡계곡 지역과 법주사 지역 내에 위치한 지역 중에서 인간의 의한 교란이 가장 큰 도로개설지역, 교란이 중간 정도인 등산로지역 그리고 간섭이 거의 없는 출입통제지역을 선택하여 산림생태계에서 인간의 교란 정도에 따른 조류군집의 차이를 연구하였다. 번식기와 비번식기의 조사(n=12)에서 조류의 종수와 개체수, 종다양도 및 밀도에서는 세 지역 사이에 유의적인 차이가 나타나지 않았다. 그러나 번식기의 조사(n=9)에서는 조류의 종수(Kruskal Wallis, $x^2$=10.32, p=0.006)와 개체수(Kruskal Wallis, $x^2$=7.118, p=0.028) 및 종다양도(Kruskal Wallis, $x^2$=9.847, p=0.007)가 인간에 의한 교란이 중간정도인 등산로 지역에서 가장 높게 나타났다. 그러나 번식기 조류 군집의 영소 및 취식 길드 분석에서는 세 지역 사이에 영소 및 취식 길드 분포비율은 차이가 나타나지 않았다. 영소길드는 세 지역 모두 나무구멍 영소길드가 가장 높았고, 취식길드는 수관층 취식길드가 가장 높게 나타났다.

• 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.

• 한국환경복원기술학회지
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• 제23권5호
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• pp.15-27
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• 2020

This study was carried out four times on 2005 and 2006, respectively May and October to understand the bird community and habitat using condition in the Daegu Bulnogoboon Jayeon Madang (DBJM). In this study, 34 species and 332 individuals were observed. The dominant species were Passer montanus 22.0%, Pica pica 18.1%, Hypsipetes amaurotis 6.02% and Sinosuthora webbiana 5.72%, and the species diversity was 2.797. With migration, the highest number and percentage to the lowest was residents 61.7%, summer visitors 26.5% and winter visitors 11.8%. Among 24 species which bred(check or possibility) in the DBJM, canopy was 50.0%, hole was 37.5% and bush was 12.5% in their nesting guilds. In foraging guilds in breeding season was canopy was 58.1%, water was 19.3% and bush was 16.1%, and in non-breeding season, canopy was 54.8%, water 22.6% and bush 19.3%. For the habitats of the birds in the DBJM, wetlands including reservoir area were used by herons, ducks and Hirundo rustica, grassland area was used by Sinosuthora webbiana, buntings and Passer montanus, and forest area was used by Streptopelia orientalis, woodpeckers, Hypsipetes amaurotis and tits. The number of species and individuals of birds observed in the DBJM was higher than other urban parks. We suggest that this was attributed to various man-made habitats such as wetland with reservoir, grassland and forest area constructed in the DBJM.

• Journal of Ecology and Environment
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• 제41권3호
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• pp.54-65
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• 2017

Background: "Igune," a traditional agricultural landscape in the Tohoku region of Japan, is characterized by small-scale artificial woodlots surrounding a farmer's house that are interspersed with paddy fields. During the rapid economic growth of Japan over recent decades, some igune woodlots have been abandoned or logged. Biodiversity conservation is an important issue worldwide, and traditional agricultural landscapes are of particular interest. To elucidate the role of igune landscapes in conserving biodiversity, we examined the effects of environmental factors on avian communities. Results: The study was conducted in the suburban areas of Oshu and Hanamaki cities, Iwate Prefecture, Japan, at eight sites that varied in the density and area of igune woodlots within the landscape. Bird surveys were conducted from the middle to late breeding season, and several environmental factors of the igune landscape were also measured. The results of canonical correspondence analysis indicated that the characteristics of avian communities were mainly determined by the total forested area in the landscape. Increased total forested area and shrubs layer of igune woodlots did not cause a reduction in number of bird species of any habitat and foraging types, while increased both in species number and abundance of insectivores and forest species. The number of raptor species increased in igune sites without shrubs. Conclusions: Our results suggest that maintaining igune landscapes may enhance avian diversity within this landscape, although the effects of shrubs within igune varied; developed bush communities increased the evenness of the avian community, whereas some raptor species preferred an open forest understory.

• 한국환경복원기술학회지
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• 제21권5호
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• pp.97-110
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• 2018

The purpose of this study is to provide basic data and evidence for the habitat improvement of wild birds in urban stream by analyzing changes in habitat characteristics of wild birds by riparian forest construction in Yangjae stream in Seoul. In Gangnam-gu, the multi layered riparian forest consisting of landscape trees and shrubs was formed on the slope. In Seocho-gu, the vertical vegetation structure of woody and herbaceous wetland plants was good. In Gangnam-gu, the vegetation area of the slope increased and the vertical stratification structure affected the species diversity of the forest birds. The number of species and individuals of plovers, sandpipers and wagtails decreased due to the impact of bicycle roads and trails. The poor forests on the levee slope in Seocho-gu affected the habitat selection and migration of the forest birds. The willows and amur silver-grasses formed in the riverside have been developed into the riparian forest, thus stabilizing the habitat of water birds by blocking disturbances from the influence of the trails.

• 한국환경복원기술학회지
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• 제8권1호
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• pp.17-26
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• 2005

Ecological corridor is the facility to connect two habitats fragmented by roads, dam, housing and industrial area. Critics of faunal corridors have suggested that they are simply an untested application of unproved island biogeography theory. But, everyone agree that ecological corridor is important useful structural components that help animal movement in fragmented landscapes. There are 52 ecological corridors in Korea. We investigated 43 ecological corridors of these and recorded the size of corridor, planting species, management and growth condition. We compared planting species to nearby exiting vegetation species and structure. We found that there are no considerations for many aspects of planting, for example, planting species, structure, animal migration and behavior, surrounding vegetation etc. Expecially, It was ignored management of plants, difference of surrounding vegetation, lacks of diverse planting species and structure. We suggest planting the native species of tall tree, shrub and ground cover, edge planting for transitional space between road and natural habitat, planting for foraging and breeding of target animal, diverse layer vegetation, and open space of center for rapid animal dispersal.