• 제목/요약/키워드: Urban habitat

검색결과 649건 처리시간 0.024초

Ecological health assessments using multiple parameters of fish blood tissues to community along with water chemistry in urban streams

  • Kang, Han-il;Choi, Ji-Woong;Hwang, Seock-Yeon;An, Kwang-Guk
    • Journal of Ecology and Environment
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    • 제38권3호
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    • pp.307-318
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    • 2015
  • The objectives of this study were to identify multi-level stressors from blood biomarkers to community-level bioindicators and diagnose the stream ecosystem health in polluted streams. Blood chemistry such as total protein ($T_{Pro}$), blood urea nitrogen ($B_{UN}$), total cholesterol ($T_{Cho}$) and $A_{lb}$umin ($A_{lb}$) were analyzed from sentinel fish tissues; the functions of kidney, gill and liver were significantly decreased in the impacted zone ($I_z$), compared to the control zone ($C_z$). Histopathological analysis showed that fish liver tissues were normal in the $C_z$. Fish liver tissues in the $I_z$, however, showed large cell necrosis and degeneration and also had moderate lobular inflammation and inflammatory cell infiltration of lymphocytic histocytes. Species biotic index (SBI) at species level and stream health assessment (SHA) at community level indicated that chemical impacts were evident in the $I_z$ (ecological health; poor - very poor), and this was matched with the blood tissue analysis and histopathological analysis. The impairments of the streams were supported by water chemistry analysis (nitrogen, phosphorus). Tolerance guild analysis and trophic guild analysis of fish were showed significant differences (P < 0.01) between $C_z$ and $I_z$. Overall, multiple parameter analysis from biomarker level (blood tissues) to bioindicator level (community health) showed significantly greater impacts in the $I_z$ than $C_z$. This approach may be effective as a monitoring tool in identifying the multilateral and forthcoming problems related to chemical pollution and habitat degradation of stream ecosystems.

Elevational Distribution of Breeding Bird Communities in Seoraksan National Park, Korea

  • Hwang, Hyun-Su;Lee, Jae-Kang;Eom, Tae-Kyung;Bae, Ho-Kyoung;Lee, Dong-Ho;Lim, Jong-Hwan;Jung, Sung-Cheol;Park, Chan-Ryul;Rhim, Shin-Jae
    • 한국산림과학회지
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    • 제109권1호
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    • pp.109-114
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    • 2020
  • In this study, the elevational distribution of breeding birds in Seoraksan National Park, Korea was investigated. Forty-six species of birds were documented from line transect surveys taken from Seorakdong at 230 m above sea level (a.s.l.) to the Daechungbong summit at 1708 m asl. Birdspecies richness and diversity were highest in Seorakdong and lowest at the Daechungbong summit. As elevation increased, bird species richness and diversity decreased, with a humped-shape trend being observed between 700 m and 1200 m a.s.l. Stepwise analyses revealed that breeding bird species diversity indices were significantly negatively correlated with elevation (r2 = 0.327, P < 0.001) and positively correlated with vegetational coverage (r2 = 0.324, P = 0.046). Higher elevations supported fewer birds than low and intermediate elevations. Projections at the local scale, including data on behavior and habitat use by birds, will be necessary for optimal conservation and management of the bird communities in Seoraksan National Park.

Seismic Performance of High-rise Concrete Buildings in Chile

  • Lagos, Rene;Kupfer, Marianne;Lindenberg, Jorge;Bonelli, Patricio;Saragoni, Rodolfo;Guendelman, Tomas;Massone, Leonardo;Boroschek, Ruben;Yanez, Fernando
    • 국제초고층학회논문집
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    • 제1권3호
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    • pp.181-194
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    • 2012
  • Chile is characterized by the largest seismicity in the world which produces strong earthquakes every $83{\pm}9years$ in the Central part of Chile, where it is located Santiago, the capital of Chile. The short interval between large earthquakes magnitude 8.5 has conditioned the Chilean seismic design practice to achieve almost operational performance level, despite the fact that the Chilean Code declares a scope of life safe performance level. Several Indexes have been widely used throughout the years in Chile to evaluate the structural characteristics of concrete buildings, with the intent to find a correlation between general structural conception and successful seismic performance. The Indexes presented are related only to global response of buildings under earthquake loads and not to the behavior or design of individual elements. A correlation between displacement demand and seismic structural damage is presented, using the index $H_o/T$ and the concrete compressive strain ${\varepsilon}_c$. Also the Chilean seismic design codes pre and post 2010 Maule earthquake are reviewed and the practice in seismic design vs Performance Based Design is presented. Performance Based Design procedures are not included in the Chilean seismic design code for buildings, nevertheless the earthquake experience has shown that the response of the Chilean buildings has been close to operational. This can be attributed to the fact that the drift of most engineered buildings designed in accordance with the Chilean practice falls below 0.5%. It is also known by experience that for frequent and even occasional earthquakes, buildings responded elastically and thus with "fully operational" performance. Taking the above into account, it can be said that, although the "basic objective" of the Chilean code is similar to the SEAOC VISION2000 criteria, the actual performance for normal buildings is closer to the "Essential/Hazardous objective".

Beehive (Hexagrid), New Innovated Structural System for Tall Buildings

  • Nejad, Peyman Askari
    • 국제초고층학회논문집
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    • 제5권4호
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    • pp.251-262
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    • 2016
  • Tall Buildings have been one of the most prominent symbols of economic growth for nearly a century. Yet, in the aftermath of the tragedies of September 11, "signature" Tall buildings have become the focus of much debate. The structural systems today are undergoing a major evolution to address the ability of providing flexibility in the design and use of the building together with sustainability (Green) and cost-effective system. This paper describes a new invented structural system, evolutionary structural analysis and design of Tall buildings, which involves the entire analysis process, including conceptual and design stages and comparison with the existing Tall building. This study presents an new innovative structural system, Beehive (Hexagrid), for Tall buildings. The final results are achieved by modeling an 80 story Tall building with the optimized angle and topology of hexagon members by using a computer analysis, ETABS finite element analysis. The objective function of this system is to use one structural system in order to both maximize Eigen frequency for resisting dynamic responses and minimize mean compliance for static responses. Finite element analysis is carried out by using standardized materials. Optimal Hexagrid topologies with the highest stiffness are finally determined to resist both static and dynamic behaviors. Holistic design integration approaches between structures and facades to save energy for environmental control are studied. Innovative design ideas to control structural motion as well as to utilize that motion to harness energy are discussed. Considering abundant emergence of tall buildings all over the world in recent years, the importance of the studies presented in this paper cannot be overemphasized for constructing more sustainable built environments.

생태네트워크 구축을 위한 목표종 선정에 관한 연구 - 판교신도시를 사례로 - (Selecting Target Species for Urban Ecological Network Construction - Focus on Pangyo New Town -)

  • 최희선;김현애;김귀곤
    • 한국환경복원기술학회지
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    • 제11권5호
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    • pp.12-24
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    • 2008
  • With recent emphasis on the creation of environment-friendly new towns, introduction of ecological facilities for habitation and migration of wild animal's species is requested when developing new towns. In order to introduce such facilities, building an eco-network within the site based on the connectivity of the source area and habitats is essential in new town development. Therefore, this study mainly aimed at selecting species targeted for building an eco-network in Pangyo new town, which is intended to be an environment-friendly city. Therefore, criteria for selecting target species were generated. Then, species observed within the site through field surveys and literature review was evaluated based on the selection criteria and items. By totaling the score, a list of appropriate targeted species was finalized. Among species surveyed and observed in the site, appropriate target species that may be selected for Pangyo new town's eco-network include Falco tinnunculus interstinctus, Accipiter soloensis, Picus canus, Paradoxornis webbiana, Parus palustris, Parus ater, Parus major and Passer montanus Egretta in birds, Asiatic chipmunk, Nyctereutes procyonoides in mammals. For Pangyo new town, it is essential to create living environment and build a network for major wild animal species within the site based on target species. This will play a crucial role in building a reasonable ecological network enabling harmonious co-existence between mankind and nature. In order to build an ecological network successfully, follow-up studies need to be conducted on restoration technology and methods required for creating habitats appropriate to target species.

초고층빌딩의 비정형 곡면형태 조합 및 복합관계에 관한 연구 (A Study on the Convergence Relativity of the Combining Curved Forms of Tall Buildings)

  • 박상준
    • 한국콘텐츠학회논문지
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    • 제20권3호
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    • pp.190-199
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    • 2020
  • 본 연구는 세계 각지에서 초고층건물들이 사회적, 경제적 기반으로 순위를 경쟁하듯이 증가하고 있는 추세에 있어서 다양한 형태변형의 가능성 가운데 패러다임을 정립하는데 있다. 또한 초고층건물은 도시, 국가를 상징하기 때문에 관광자원으로 이용될 뿐만 아니라 개성 있는 랜드마크적 역할의 중요성을 가지고 미래지향적 곡면 형태를 모색하고자 한다. 본 연구의 목적은 복잡·다양한 비정형 건축형태 가운데 특히 곡선 형태에 대한 세분화를 통해 형태조합 및 복합관계를 유추하는데 목적이 있다. 따라서 곡면형을 정형화곡면, 단방향곡면, 이중휨곡면 등으로 구분하여 조형적 형태를 인지하는 방식보다는 실질적인 설계가 이루어지는 시공성을 근거하기 위해 세계초고층협의회(CTBUH)에서 선정한 순위 자료 중 총 50개의 초고층건물을 연구대상으로 하였다. 이러한 유형 분류는 초고층건축의 설계에 있어 다양한 곡면형을 추구하는 디자인과정에 합리적으로 관여하는 기초적 자료로 활용 될 수 있을 것이다.

국내 주요 도시의 비오톱유형 분류체계 비교 (Comparisons of Classification System of Biotope Type in Major Korean Cities)

  • 최진우
    • 한국환경생태학회지
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    • 제24권1호
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    • pp.78-86
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    • 2010
  • 국내 주요 도시에서 수행된 비오톱유형 분류는 생물서식처 관점보다는 토지이용 개념에 한정되어 분류되었고, 생태적 가치에 따라 상세하게 분류되지 못하였다. 비오톱유형은 지역적 특성을 고려하여 생물서식처 관점에 따라 분류되어야 한다. 본 논문은 비오톱유형 분류에 사용되는 분류위계, 분류항목, 분류요인, 분류지표, 분류기준, 분류key 등 분류인자의 개념적 틀을 명확하게 설정하고 사례도시의 비오톱유형 분류결과에 적용하여 문제점을 고찰하고 비오톱유형 분류체계 개선방향을 제안하였다. 비오톱유형 분류체계는 위계별로 분류의 기본 수준과 기준을 마련하여 일관된 분류 특성을 가져야 한다. 분류지표는 생물적 요인, 무생물적 요인, 인간행태적 요인을 고려하여 적용되어야 한다. 비오톱유형은 일반인들과 계획가들이 이해하기 쉽도록 분류지표와 분류key의 표준화와 더불어 지역 비오톱 특성을 반영할 수 있도록 분류key와 분류기준의 특성화를 반영하는 것이 필요하다.

Numerical study on Floor Response Spectrum of a Novel High-rise Timber-concrete Structure

  • Xiong, Haibei;Zheng, Yingda;Chen, Jiawei
    • 국제초고층학회논문집
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    • 제9권3호
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    • pp.273-282
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    • 2020
  • An innovative high-rise timber-concrete hybrid structure was proposed in previous research, which is composed of the concrete frame-tube structure and the prefabricated timber modules as main structure and substructures, respectively. Considering that the timber substructures are built on the concrete floors at a different height, the floor response spectrum is more effective in estimating the seismic response of substructures. In this paper, the floor response spectra of the hybrid structure with different structural parameters were calculated using dynamic time-history analysis. Firstly, one simplified model that can well predict the seismic response of the hybrid structure was proposed and validated. Then the construction site, the mass ratio and the frequency ratio of the main-sub structure, and the damping ratio of the substructures were discussed. The results demonstrate that the peaks of the floor response spectra usually occur near the vibration periods of the whole structure, among which the first two peaks stand out; In most cases, the acceleration amplification effect on substructures tends to be more evident when the construction site is farther from the fault rupture; On the other hand, the acceleration response of substructures can be effectively reduced with an appropriate increase in the mass ratio of the main-sub structure and the damping ratio of the substructures; However, the frequency ratio of the main-sub structure has no discernible effect on the floor response spectra. This study investigates the characteristics of the floor response spectrum of the novel timber-concrete structure, which supports the future applications of such hybrid structure in high-rise buildings.

A Multiple Database-Enabled Design Module with Embedded Features of International Codes and Standards

  • Kwon, Dae Kun;Kareem, Ahsan
    • 국제초고층학회논문집
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    • 제2권3호
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    • pp.257-269
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    • 2013
  • This study presents the development of an advanced multiple database-enabled design module for high-rise buildings (DEDM-HR), which seamlessly pools databases of multiple high frequency base balance measurements from geographically dispersed locations and merges them together to expand the number of available building configurations for the preliminary design. This feature offers a new direction for the research and professional communities that can be utilized to efficiently pool multiple databases therefore expanding the capability of an individual database and improving the reliability of design estimates. This is demonstrated, in this study, by the unprecedented fusion of two major established databases, which facilitates interoperability. The DEDM-HR employs a cyberbased on-line framework designed with user-friendly/intuitive web interfaces for the convenient estimation of wind-induced responses in the alongwind, acrosswind and torsional directions with minimal user input. In addition, the DEDM-HR embeds a novel feature that allows the use of wind characteristics defined in a code/standard to be used in conjunction with the database. This supplements the provisions of a specific code/standard as in many cases guidance on the acrosswind and torsional response estimates is lacking. Through an example, results from several international codes and standards and the DEDM-HR with the embedded features are compared. This provision enhances the scope of the DEDM-HR in providing an alternative design tool with nested general provisions of various international codes and standards.

Smart System Identification of Super High-Rise Buildings using Limited Vibration Data during the 2011 Tohoku Earthquake

  • Ikeda, A.;Minami, Y.;Fujita, K.;Takewaki, I.
    • 국제초고층학회논문집
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    • 제3권4호
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    • pp.255-271
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    • 2014
  • A method of smart system identification of super high-rise buildings is proposed in which super high-rise buildings are modeled by a shear-bending system. The method is aimed at finding the story shear and bending stiffnesses of a specific story only from the horizontal floor accelerations. The proposed method uses a set of closed-form expressions for the story shear and bending stiffnesses in terms of the limited floor accelerations and utilizes a reduced shear-bending system with the same number of elements as the observation points. A difficulty of prediction of an unstable specific function in a low frequency range can be overcome by introducing an ARX model and discussing its relation with the Taylor series expansion coefficients of a transfer function. It is demonstrated that the shear-bending system can simulate the vibration records with a reasonable accuracy. It is also shown that the vibration records at two super high-rise buildings during the 2011 Tohoku (Japan) earthquake can be simulated with the proposed method including a technique of inserting degrees of freedom between the vibration recording points. Finally it is discussed further that the time-varying identification of fundamental natural period and stiffnesses can be conducted by setting an appropriate duration of evaluation in the batch least-squares method.