• Title/Summary/Keyword: Specific habitat

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Structural Design of Vibration Controlled Tall Building with Overhang Structure

  • Ishibashi, Yoji;Yoshizawa, Katsuhito;Ogawa, Ichiro;Tamari, Masatoshi;Nagayama, Kenji;Oki, Hatsuka
    • International Journal of High-Rise Buildings
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    • v.8 no.3
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    • pp.177-183
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    • 2019
  • This paper describes the structural design of a 212 m tall building currently under construction in the Tokiwabashi District Redevelopment Project facing Tokyo Station. In this project there was a requirement to rationally solve many issues arising from the conditions of the redevelopment project. In particular, the following two points were considered to be important from the point of view of structural design. 1) To provide an overhang frame with the perimeter columns on the lower stories inclined, in order to enable a typical floor area that greatly exceeded the limitations of the underground structure shape. 2) To provide high grade seismic performance for the office buildings to be constructed on prime city center land. LSCVCS (Lower Stories Concentrated Vibration Control System) was proposed as the method of rationally designing the overhang frame, which is an extremely disadvantageous element in the structural scheme of the tall building with a large slenderness ratio. LSCVCS is a system to provide effective damping by arranging vibration control devices in a concentrated manner in a lower story with large story height, that produces large deformation in an earthquake. Also, the vibration control devices arranged in the lower story are limited to viscous devices, to take into consideration the residual deformation of the overhang frame after an earthquake. The results of investigations into the specific effects of the system for the seismic design are reported, including Performance-based seismic design.

A Study on the Guidelines for Creating Wildlife Crossing through Environmental Impact Assessment (환경영향평가 협의 시 생태통로 조성을 위한 가이드라인 마련)

  • Park, Yong-Su;Shim, Yun-Jin
    • Journal of Environmental Impact Assessment
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    • v.28 no.3
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    • pp.287-298
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    • 2019
  • This study found that wildlife crossing created through environmental impact assessments didn't reduce the number of wildlife accidents on the road by review of "A Study on the Legal and Institutional Review for Reproving Bio-Mobile in Environmental Impact Assessment(2018)". Specific considerations to be reviewed at each stage of the environmental impact assessment consultation were presented for practical site application. Therefore, in this study, the consultation steps for environmental impact assessment were presented in five stages, including planning, design, construction, monitoring, maintenance and management, and detail of the items to be reviewed by public officer. It will be able to prevent loss of habitats and improve biodiversity by improving the practice and institutional problems that were planned and designed at the time of construction.

Island-Biogeographical Characteristics of Insular Flora in Southern Sea of Jeollanamdo, Korea (전라남도 남해안 도서식물상의 도서생물 지리학적 특성)

  • Kim, Hyun Hee;Kim, Da Bin;Won, Hyun Kyu;Kim, Chan Soo;Kong, Woo Seok
    • Journal of Climate Change Research
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    • v.7 no.2
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    • pp.143-155
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    • 2016
  • Present work aims to establish the countermeasure for the better maintenance and preservation of insular floristic diversity at the South Sea of Jeollanamdo Province, ROK, where unique ecosystems are under threat due to climate change, anthropogenic disturbance and habitat destruction. Numerous flora reports from 15 inhabited islands and 60 uninhabited islands as well as field survey data are collated for the compilation of floristic data base and island biogeographical analysis. Out of the 1,940 vascular plant species from 180 families occurring in studies areas, 30.1 percentage or 584 plant species are physiognomically belonging to arboreal plants. Average number of species at individual island is numbered about 222 species, but it varies from about 591 species at the inhabited islands to 129 species at the uninhabited islands. Only 0.15 percentage of species with high proportion above 0.9 in its relative occurrence rate occurs at 68 islands and it includes three species, such as Pinus thunbergii, Eurya japonica and Pteridium aquilinum var. latiusculum. However, about 68 percentage of plant species occurring in study area is confined their distribution to less than seven islands. Presence of high proportion of notable plants in small islands, i.e., 10 critically endangered species compared with 5.5 species in average, 9 endangered species (average 4.2 spp.) at Sonjookdo, and 7 critically endangered species, 8 endangered species at Sokomundo may due to existence of diverse geological and topographical environmental diversity as well as lower human population density and remoteness from the mainland. Since island is small in size and geographically isolated, minor environmental and ecological burdens can cause the critical damages to the diversity of flora and vegetation, urgent island biogeographical research is needed for the scientific conservation and management of island biodiversity.

Histological Development of the Digestive System in Artificially Produced Anguilla japonica Larvae (인공생산 뱀장어(Anguilla japonica) 자어의 소화기관 발달 특성)

  • Shin, Min Gyu;Kim, Shin-Kwon;Lee, Bae-Ik;Choi, Youn Hee;Ryu, Yongwoon
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.54 no.3
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    • pp.298-310
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    • 2021
  • Freshwater eel Anguilla japonica is a commercially important species in East Asia. However, given the continuously decreasing resources due to many problems as climate change, habitat destruction and overfishing, mass seed production is crucial. In particular, the eel larvae present a unique life history, spending prolonged periods in the Pacific Ocean. Therefore, finding suitable feed that lasts through the long larval stages is rather difficult. In the present study, we histologically observed the development of digestive organs for 50 days after hatching (DAH). The endogenous reserves were completely absorbed at 7 DAH, and the first exogenous feeding started thereafter. The teeth appeared at 4 DAH and dramatically changed from needle-like to broad-based types by 50 DAH. The intestine remained as straight gut until 50 DAH. The intestinal cilia appeared first at 6 DAH and their density continuously increased thereafter. Interestingly, goblet cells appeared in the intestine, but not in the esophagus, where these cells are commonly observed in other teleosts. In addition, high amounts of eosinophil substances, assumed to be zymogen granules, accumulated in the pancreas, suggesting a specific digestive strategy of this species. Overall, these observations largely update the previous reports and can be useful to improve A. japonica seed production.

Dietary Habitats of Spinyhead Sculpin Dasycottus setiger in the Coastal Waters of the East Sea, Korea (동해 연안에 출현하는 고무꺽정이(Dasycottus setiger)의 섭식생태)

  • Park, Joo Myun;Jung, Hae Kun;Kim, Beon Sik;Jung, Young Woo;Lee, Chung Il
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.55 no.3
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    • pp.345-352
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    • 2022
  • In this study, the dietary habits of the spinyhead sculpin Dasycottus setiger were investigated based on 156 specimens collected seasonally between May 2018 and February 2019 from the East Sea off the Korean coast. In terms of the weight contribution (%W), the main food items of the spinyhead sculpin were found to be teleosts (33.5%), followed by carid shrimps (13.8%), amphipods (13.3%), cephalopods (12.0%), and polychaetes (7.1%). Dietary analyses based on the weight contribution of different prey taxa in the diet of the spinyhead sculpin revealed considerable variation in the dietary composition in terms of the sampling region and fish size implying intra-specific dietary segregation. The spinyhead sculpin showed a size-related trends in dietary shift from amphipods to carid shrimps and teleosts in northern region, and from carid shrimps and mysids to teleosts and cephalopods in middle eastern coast. Multivariate analyses of dietary changes revealed that the dietary composition of spinyhead sculpin is significantly associated with the sampling site, but not the fish size. Amphipods contributed more to the diets of the northern population, while mysids typified the diets of spinyhead scuplin inhabiting the middle eastern coast, indicating differences in available food resources between the two study regions.

Numerical Simulation on Disproportionate Collapse of the Tall Glulam Building under Fire Conditions

  • Zhao, Xuan;Zhang, Binsheng;Kilpatrick, Tony;Sanderson, Iain
    • International Journal of High-Rise Buildings
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    • v.10 no.4
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    • pp.311-321
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    • 2021
  • Perception of the public to structural fires is very important because there are only a number of tall timber buildings constructed in the world. People are hesitating to accept tall timber buildings, so it is essential to ensure the first generation of tall timber buildings to a very high standard, especially fire safety. Right now, there are no specific design standards or regulations for fire design of tall timber buildings in Europe. Even though heavy timber members have better fire resistance than steel components, many conditions still need to be verified before considering the use of timber materials, e.g. fire spread, post-fire collapse, etc. This research numerically explores the structural behaviours of a tall Glulam building when one of its internal Glulam (Glued laminated timber) columns fails after sustaining a full 120-min standard fire and is removed from the established finite element building model created in SAP2000. The numerical results demonstrate that the failure and removal of the selected internal Glulam column may lead to the local failure of the adjacent CLT (Cross laminated timber) floor slabs, but will not lead to large disproportionate damage and collapse of the whole building. Here, the building is assumed to be located in Glasgow, Scotland, UK.

Comparisons of fatty acid accumulation patterns of two filter feeders, Branchinella kugenumaensis and Daphnia magna in a controlled environment

  • Dongwoo, Yang;Seonah, Jeong;Jihee, Kim;Sangkyu, Park
    • Journal of Ecology and Environment
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    • v.46 no.4
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    • pp.304-315
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    • 2022
  • Background: Filter-feeding zooplankton has limited food resources owing to their habitat. Consequently, it is crucial for them to acquire all essential compounds, such as fatty acids (FAs) and amino acids, from confined diets. To elucidate the trophic transfer of FAs to filter feeders, the primary consumers in freshwater ecosystems, we compared the FA accumulation patterns of two species of filter-feeding zooplankton, Daphnia magna and Branchinella kugenumaensis, in a laboratory experiment. Experimental neonates and nauplii preyed on a single phytoplankton species (Selenastrum capricornutum) for three days after hatching prior to diet switching. Five replicates per feeding group in each species were fed on six different types of mixed phytoplankton diet for 10 days after diet switching. Subsequently, the consumers and diets were harvested and FAs were extracted. Results: Principal component analysis showed that the FA profiles of zooplankton were well-grouped by species and diet. Although diet affects the FA profiles of consumers, they exhibit different FA accumulation patterns. D. magna had a higher 18C-ω3 content and ω3/ω6 ratio than did B. kugenumaensis. In contrast, B. kugenumaensis had higher contents of 18:1ω7 and 20:5ω3 (eicosapentaenoic acid), 22:6ω3 (docosahexaenoic acid), and a higher ratio of ∑18C monounsaturated FAs to ∑18C-ω3 polyunsaturated FAs than did D. magna. Conclusions: This study showed that two primary consumers, D. magna and B. kugenumaensis, fed the same diet had different assimilation patterns of FAs under controlled environments. Specific FA accumulation patterns in filter feeders can provide information on the transfer process of various FAs to high-trophic organisms.

VSimulators: A New UK-based Immersive Experimental Facility for Studying Occupant Response to Wind-induced Motion of Tall Buildings

  • Antony Darby;James Brownjohn;Erfan Shahabpoor;Kaveh Heshmati
    • International Journal of High-Rise Buildings
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    • v.11 no.4
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    • pp.347-362
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    • 2022
  • Current vibration serviceability assessment criteria for wind-induced vibrations in tall buildings are based largely on human 'perception' thresholds which are shown not to be directly translatable to human 'acceptability' of vibrations. There is also a considerable debate about both the metrics and criteria for vibration acceptability, such as frequency of occurrence or peak vs mean vibration, and how these might vary with the nature of the vibration. Furthermore, the design criteria are necessarily simplified for ease of application so cannot account for a range of environmental, situational and human factors that may enhance or diminish the impact of vibrations on serviceability. The dual-site VSimulators facility was created specifically to provide an experimental platform to address gaps in understanding of human response to building vibration. This paper considers how VSimulators can be used to inform general design guidance and support design of specific buildings for habitability, in terms of vibration, which allow engineers and clients to make informed decisions with regard to sustainable design, in terms of energy and financial cost. This paper first provides a brief overview of current vibration serviceability assessment guidelines, and the current understanding and limitations of occupants' acceptability of wind-induced motion in tall buildings. It then describes how the dual-site VSimulators facility at the Universities of Bath and Exeter can be used to assess the effects of motion and environment on human comfort, wellbeing and productivity with examples of how the facility capabilities have been used to provide new, human experience based experimental research approaches.

Impact, management, and use of invasive alien plant species in Nepal's protected area: a systematic review

  • Sunita Dhungana;Nuttaya Yuangyai;Sutinee Sinutok
    • Journal of Ecology and Environment
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    • v.48 no.2
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    • pp.182-195
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    • 2024
  • Background: Invasive alien plant species (IAP) significantly threaten Nepal's protected areas and local communities. Understanding their distribution, impact, management, and utilization is essential for developing effective management strategies and sustainable utilization practices. The systematic literature review of publications from 2010 to 2023. The search was conducted through the database Nepal Journal online database (NepJOL) and Google Scholar, yielding an initial pool of 4,304 publication. After applying inclusion and exclusion criteria; we meticulously reviewed 43 articles for data extraction. Results: Seventeen IAP are found in protected area, Nepal with the highest prevalence observed in Koshi Tappu Wildlife Reserve, followed by Chitwan and Sukhlaphanta National Park. The most problematic species in terrestrial ecosystems are Mikania micrantha, Lantana camara, and Chromolaena odorata. The grassland ecosystems of wildlife habitats, primarily in the Terai and Siwalik regions, are the most invaded. Various management approaches are employed to mitigate the spread and impact of IAP, including mechanical methods such as uprooting, burning, and cutting. However, these methods are costly, and context-specific interventions are needed. The study also explores the potential use of IAP for economic, ecological, or cultural purposes, such as medicinal properties, energy production potential, and economic viability. Local communities utilize these plants for animal bedding, mulching, green manure, briquette, and charcoal production. Conclusions: Applying silvicultural practices alongside mechanical management is recommended to maintain a healthy terrestrial ecosystem and utilize the removed biomass for valuable products, thereby reducing removal costs and increasing income sources, potentially benefitting both local communities and wildlife in protected areas.

Comparison of plant species diversity and its relationship with physical environmental factors in Gotjawal Forest, Jeju Island, Republic of Korea, using the modified Whittaker plot method

  • Ju-Seon Lee;Young-Han You;Ji-Won Park;Yeo-Bin Park;Yoon-Seo Kim;Jung-Min Lee;Hae-In Yu;Bo-Yeon Jeon;Kyeong-Mi Cho;Eui-Joo Kim
    • Journal of Ecology and Environment
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    • v.48 no.3
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    • pp.247-255
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    • 2024
  • Background: To effectively understand and evaluate plant diversity in a specific area and make meaningful comparisons between regions, standardized methods that measure diversity irrespective of survey plot size are crucial. This study proposes a model equation for comparing plant species diversity using the modified Whittaker plots. Plant species diversity was measured in two Gotjawal areas on Jeju Island, where the coexistence of northern and southern limit species significantly impacts diversity. By analyzing the relationship between plant species diversity and environmental factors, the study clarified the characteristics of plant and habitat diversity in the Gotjawal ecosystem. Results: The species richness of vascular plants, herbaceous plants, and woody plants increased with area and was higher in Jeoji Gotjawal than in Seonheul Gotjawal. Similarly, the species turnover rate (slope value) was higher in Jeoji Gotjawal (4.37) than in Seonheul Gotjawal (3.85). This indicates that the species richness in Jeoji Gotjawal increases more with the expansion of the survey area (1-1,000 m2), reflecting a faster species turnover rate. Additionally, in Gotjawal areas, species richness increased with greater leaf litter depth, elevation, slope, and rock ratio. These results indicate that differences in plant species diversity were attributed to soil environmental factors. Conclusions: The plant species diversity of Gotjawal, surveyed using standardized methods, was lower than that of forested areas in the central region of South Korea where the same method was applied. Most previous studies on species diversity likely compared diversity without considering a consistent survey area. Therefore, when comparing plant species diversity domestically and globally, it emphasizes the need for the use of standardized survey methods.