• Title/Summary/Keyword: New habitat

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Nonlinear incremental dynamic analysis and fragility curves of tall steel buildings with buckling restrained braces and tuned mass dampers

  • Verki, Amir Masoumi;Preciado, Adolfo
    • Earthquakes and Structures
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    • v.22 no.2
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    • pp.169-184
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    • 2022
  • The importance of seismicity in developing countries and the strengthening of buildings is a topic of major importance. Therefore, the study of several solutions with the development of new technologies is of great importance to investigate the damage on retrofitted structures by using probabilistic methods. The Federal Emergency Management Agency considers three types of performance levels by considering different scenarios, intensity and duration. The selection and scaling of ground motions mainly depends on the aim of the study. Intensity-based assessments are the most common and compute the response of buildings for a specified seismic intensity. Assessments based on scenarios estimate the response of buildings to different earthquake scenarios. A risk-based assessment is considered as one of the most effective. This research represents a practical method for developing countries where exists many active faults, tall buildings and lack of good implementable approaches. Therefore, to achieve the main goal, two high-rise steel buildings have been modeled and assessed. The contribution of buckling-restrained braces in the elastic design of both buildings is firstly verified. In the nonlinear static range, both buildings presented repairable damage at the central top part and some life safety hinges at the bottom. The nonlinear incremental dynamic analysis was applied by 15 representative/scaled accelerograms to obtain levels of performance and fragility curves. The results shown that by using probabilistic methods, it is possible to estimate the probability of collapse of retrofitted buildings by buckling-restrained braces and tuned mass dampers, which are practical retrofitting options to protect existing structures against earthquakes.

A Study on Sustainable Greenspace based on Urban Remodeling Design of an Old Apartment Building

  • Myung Sik Lee;Seung Ryeol Min
    • International Journal of High-Rise Buildings
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    • v.12 no.2
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    • pp.179-193
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    • 2023
  • It is undeniable that urban greenspace is the soul of a city. Conventional urban greenspace such as parks, community gardens, playgrounds etc. located within a city reduce the negative effects of pollution, play a major role in the survival of the urban ecosystem, and promote healthy lifestyles. Today, 55% of the world's population lives in urban areas, which is expected to increase to 68% by 2050. Projections show that urbanization and the gradual migration to urban areas combined with the fast growth of the world's population, could add another 2.5 billion people to urban areas by 2050 and almost 90% of this increase will take place in Asia(UN, 2018). As a result, many plots in the cities are and will continue to be occupied with buildings to provide residential support to the increased population. This will dangerously decrease urban greenspaces. Moreover, worldwide, food crisis, energy crisis, and social crisis is posing a great threat to the existence of mankind. Additionally, the COVID - 19 has introduced a new lifestyle where from work culture to community configuration has drastically transformed. In this scenario, residential buildings will have to serve more than just providing privacy and shelter. As urban greenspaces are being occupied by concrete residential buildings, these buildings will have to compensate for the percentage of urban green they are destroying and the issues they are imposing in the process. The goal of this thesis is to design, architecturally define and, categorize comprehensive 'sustainable Greenspace'(S.G.S) for the multi-family housing scenario. These will be different than the conventional green (veranda, rooftop green) we commonly see in residential buildings. An old, dilapidated apartment building will be the target of remodeling to fulfill the purpose of this thesis.

Morphological Characteristics and Distribution of Korean Daphne L.

  • Beom Kyun Park;Balkrishna Ghimire;Eun-Mi Sun;Dong Chan Son;Seung Hwan Oh
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2020.08a
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    • pp.27-27
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    • 2020
  • Daphne L. (Thymelaceae) comprises about 95 species distributing worldwide from N Africa, N India, SE Asia to E Asia and the coast of the Mediterranean of Europe. In Korea, five species of this genus have been described. In this study, we included four species (D. genkwa, D. pseudomezereum, D. kiusiana, D. jejudoensis) from Korea, excluding cultivated D. odora. The morphological characters through local surveys and the re-classification of the specimens collected in the Korea National Herbarium (KH) were carried out and distribution maps for each taxon were also prepared. The major characters include habit, trichomes in winter bud, leaf, and twig, phyllotaxis, inflorescence, size of calyx lobe and trichomes in the calyx tube, etc. The distribution map showed that D. genkwa is mainly distributed in the coastal area of Hwanghaenam-do, Pyeongannam-do, Jeollabuk-do and Jeollanam-do, whereas D. pseudomezereum is distributed in the limestone zone of Gangwon-do, Jeollabuk-do, and Gyeongsangbuk-do. Similarly, D. kiusiana is mostly found in Jeollanam-do, Gyeongsangnam-do, and Jeju-do. In addition, D. jejudoensis is known to be distributed in forests of Murueng, Andeok, and Seonheul-ri in Jeju-do, but recently, new habitat is discovered in the island forest areas of Jeollanam-do. However, some of these individuals showed the characteristics of D. kiusiana, thus before come to any conclusion detailed taxonomic review of D. jejudoensis and D. kiusiana is required.

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A study on the implementation plan of deposit system for management of fishing gear (어구 관리를 위한 보증금제 실행방안 연구)

  • Dong-Yang KANG;Seonghun KIM;Kyunghoon LEE;Yoo-Won LEE
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.59 no.4
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    • pp.377-386
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    • 2023
  • As discarded fishing gear settles or floats on the seabed, it destroys the spawning and habitat of fisheries resources that causes various safety accidents and adverse effects on the environment, such as generating microplastics and causing ship accidents. In order to solve this problem, this study is intended to present an implementation plan for establishing a fishing gear deposit system in order to use it as basic data for establishing policies for fishing gear management in Korea. In order to successfully implement the fishing gear deposit system, the deposit system must be established in the form of fishing gear completed at the production stage. It was found that the marking of the object should be easy, and that determining an appropriate deposit amount to motivate the return of waste fishing gear and establishing a convenient return procedure for returned waste fishing gear were important factors. In addition, transparent management of unreturned deposits and mandatory use of fishing gear subject to the deposit system for fishermen will be necessary. The role of a specialized organization to manage and operate all of these procedures is also very important. It is necessary to establish a new mandatory provision in the Fisheries Act to require fishermen who directly use fishing gear to use fishing gear with a deposit refund mark, and to ensure the implementation of the deposit system by linking it with the evaluation items of government policy projects. Since the main purpose of the deposit system is to collect discarded fishing gear, a support plan will be necessary in accordance with the purchase project for fishing waste salvaged by local governments in 2020.

Optimal Conditions for the Embryonic Development of Mussel, Mytilus galloprovincialis (지중해담치, Mytilus galloprovincialis의 발생 최적조건)

  • Sung, Chan-Gyoung;Kim, Gi-Beum;Seo, Jin-Young;Lee, Chang-Hoon;Ryu, Tae-Kwon;Han, Gi-Myung;Choi, Jin-Woo;Kim, Yong-Hyun
    • The Korean Journal of Malacology
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    • v.21 no.1
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    • pp.25-31
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    • 2005
  • The embryos of marine bivalves have been commonly used in bioassays for the quality assessment of marine environments. Although several standard protocols for developmental bioassay with bivalves have been already proposed, there have been few trials for applying these protocols in environmental assessment, or for developing new protocol with Korean species. So, there is a strong need to establish the standard bioassay protocols using bivalves commonly found in Korean waters. Prior to developing a new protocol, it is essential to know the optimum conditions for the reliable bioassay procedures. Here, we established the purpose of this study to determine the optimum bioassay conditions for successful development of a common mussel, Mytilus galloprovincialis. The conditions considered as critical for developmental bioassay, and determined in this study were; (1) temperature, (2) salinity, and (3) initial density of embryo. The optimal temperature for developmental bioassay of M. galloprovincialis was determined as $15^{\circ}C$. At this temperature, the required time for the embryo to become veliger larva was 48 hr. The acceptable range of salinity for the embryotoxicity test using M. galloprivincialis was from 30 to 35 psu, which was narrower than that of the natural habitat of adult populations. The optimum density of embryo at the beginning of bioassay was 100 embryos/ml. Over this density, the proportion of normally developed larvae decreased significantly. The results obtained in this study will serve as a basis for preparation of the standard bioassay protocol using embryo of M. galloprovincialis.

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An Study on Plant Classification System as Described in the Science Textbook of Elementary and Secondary School (초.중등학교 과학교과서(생물영역)의 식물 분류 체계에 관한 연구)

  • Yeau, Sung-Hee
    • Journal of The Korean Association For Science Education
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    • v.18 no.4
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    • pp.635-641
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    • 1998
  • The purpose of this study was to suggest a new direction of learning method in botany based on the analysis of a classification system and concepts in Science(Biology) textbooks of elementary and secondary school. Elementary and secondary school textbooks of Biology have been analyzed for plant classification system and concepts. Findings are summarized as belows. 1. In textbook of elementary school, the organization of life is grouped into Plantae and Animalia. Learning contents of plant are divided by the size and habitat. However, this system of classification might cause false concepts. Therefore, learning contents should be organized as whether they are flowering plants or not. 2. In a textbook of middle school, the organization of life is grouped into Plantae and Animalia. For a textbook of high school, it is grouped into three kingdoms; Plantae, Animalia and Prorista. With the idea of new age of Life Science, we should change the standards to 5 kingdoms; Plantae, Animalia, Proristae, Fungi and Monera. Moreover, it would be desirable if the concept of plant classification could be explained with a general outline, not by an individual interpretation focusing on characters of species only. In addition to the above indications, a learning course should provide present a standard classification according to a cognitive developemental level. It also has to teach students how to classify plant, in secondary school. Learning materials focusing on algae of the present system, but should be organized based on Seed plants.

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Study of germination for none seasonal pruning mulberry farm and their insective diseases (순상전 춘기말벌채고조의 발아상태와 충해 발생 관계)

  • 도경화
    • Journal of Sericultural and Entomological Science
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    • v.3
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    • pp.13-21
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    • 1963
  • 1. In the mulberry groves for both rearing of spring and fall, the rate of germination was 74.3 percent and the rate of the unfinished bud was 25.7 percent. 2. When the summer pruning after spring rearing was not worked, new sprouted leaves from the axillary buds of an age old branches was 74.88 percent of germination and the rest from unfinished bud during the spring showed 28.12 percent. 3. In the furrows running from north to south, new buds facing the due north were the worst but towards south-east and north-east were the best in their sprouts. 4. One year-old branches which had been raised without the summer pruning in the bush types of Morus Lhou (ser) Koidz offered a habitat where Apriona Rugico1lis Cherr could live. 5. On the grove of Morus Lhou Koidz cultivated at lower zone under a higher humidity and the shortage of sun light the appearance of Anomoneura Mori Schw was likely to happen very much. 6. One year old branches without the summer pruning produced more leaves owing to a long period of growth than branches with the summer pruning in the fall crops. 7. It is necessary to reconsider a certain distance of planting because of causing, when the summer pruning was not made in the bush plantation, a obstacle of fertilizer operation or the forth coming year's management. 8. It can not be thought the ideal method for us to raise mulberry tree such as Morus Lhou Koidz under natural form and at a short distance of planting (one another). 9. Among the species, Morus alba L. had a great deal of leaves and of the rate of germination per unit length of branch.

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New Finding on Range Expansion and Geographic Variation of Eumicrotremus jindoensis(Cyclopteridae) Collected from Boryeong in the Western Coast of Korea (한국 서해 보령에서 채집된 긴꼬리엄지도치(Eumicrotremus jindoensis)의 지역 확장 및 지리적 변이에 관한 새로운 발견)

  • Song, Young Sun;Kim, Maeng Jin;Kim, Jin-Koo
    • Korean Journal of Ichthyology
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    • v.33 no.3
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    • pp.184-190
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    • 2021
  • Since the original description of new species, Eumicrotremus jindoensis, we confirmed the first occurrence of E. jindoensis based on a single specimen (22.3 mm SL) caught by inshore stow net at the coastal waters of Boryeong of Korea. However, our specimen slightly differed from type specimens in having more vertebrae (26 vs. 21~24), longer snout (17.4% vs. 8.1~9.1%), longer preanus length (67.5% vs. 58.0~58.3%) and shorter second dorsal fin base (15.3% vs. 20.2~20.8%). Comparing with mtDNA COI and Cytb sequences, we could not find any differences in mtDNA Cytb sequences between our specimen and type specimens, which suggest that those morphological differences may belong to local variation by habitat and environmental condition between off Jindo Island and off Boryeong in Korea. Eumicrotremus uenoi is known from the southern sea of Korea narrowly (Busan, Tongyeong, and Jeju Island), the other congeneric species (E. asperrimus, E. pacificus, and E. taranetzi) from only the eastern sea of Korea, but E. jindoensis from the central coast to southern coast of western Korea.

New Record of Alien Plants, Stellaria pallida, S. ruderalis, and Cerastium pumilum (Caryophyllaceae) (미기록 외래식물 모래별꽃(Stellaria palida), 들별꽃(S. ruderalis), 애기점나도나물(Cerastium pumilum)의 보고)

  • Eun Su Kang;Jin Suk Kim;Seon Min Kim;Kang-Hyup Lee;Dong Chan Son
    • Korean Journal of Plant Resources
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    • v.36 no.4
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    • pp.299-313
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    • 2023
  • Stellaria pallida (Dumort.) Crép., S. ruderalis M. Lepší, P. Lepší, Z. Kaplan & P. Koutecký, and Cerastium pumilum Curtis are unrecorded alien species of Caryophyllaceae found in Seoul and Gyeonggi-do in the Republic of Korea. Stellaria pallida is readily distinguished from other taxa in the same genus by its petals, as it's considerably smaller than the sepals or absent. In contrast, S. ruderalis is difficult to identify as it has intermediate traits between S. media L. and S. neglecta (Lej.) Weihe. However, S. ruderlais clearly identified by seed morphology, and S. ruderalis, unlike S. media and S. neglecta, has conical shape of outer periclinal wall and papillate on the basely surface of that. Cerastium pumilum is similar to C. glomeratum Thuill. and belongs to the same subgenus (Sub gen. Fugacia); however, it has some distinct characteristics, including stamens that are primarily 8 (5-10), upper bracts with membranous edges, and the length of the pedicels and petals being longer than that of the sepals. The three of alien plants was recorded for the first time in this study, and information of their habitat, distribution map, description and photographs are presented.

Mapping Mammalian Species Richness Using a Machine Learning Algorithm (머신러닝 알고리즘을 이용한 포유류 종 풍부도 매핑 구축 연구)

  • Zhiying Jin;Dongkun Lee;Eunsub Kim;Jiyoung Choi;Yoonho Jeon
    • Journal of Environmental Impact Assessment
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    • v.33 no.2
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    • pp.53-63
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    • 2024
  • Biodiversity holds significant importance within the framework of environmental impact assessment, being utilized in site selection for development, understanding the surrounding environment, and assessing the impact on species due to disturbances. The field of environmental impact assessment has seen substantial research exploring new technologies and models to evaluate and predict biodiversity more accurately. While current assessments rely on data from fieldwork and literature surveys to gauge species richness indices, limitations in spatial and temporal coverage underscore the need for high-resolution biodiversity assessments through species richness mapping. In this study, leveraging data from the 4th National Ecosystem Survey and environmental variables, we developed a species distribution model using Random Forest. This model yielded mapping results of 24 mammalian species' distribution, utilizing the species richness index to generate a 100-meter resolution map of species richness. The research findings exhibited a notably high predictive accuracy, with the species distribution model demonstrating an average AUC value of 0.82. In addition, the comparison with National Ecosystem Survey data reveals that the species richness distribution in the high-resolution species richness mapping results conforms to a normal distribution. Hence, it stands as highly reliable foundational data for environmental impact assessment. Such research and analytical outcomes could serve as pivotal new reference materials for future urban development projects, offering insights for biodiversity assessment and habitat preservation endeavors.