• 제목/요약/키워드: environmental accounts

검색결과 282건 처리시간 0.031초

A refined higher-order shear deformation theory for bending, vibration and buckling analysis of functionally graded sandwich plates

  • Nguyen, Kien T.;Thai, Tai H.;Vo, Thuc P.
    • Steel and Composite Structures
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    • 제18권1호
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    • pp.91-120
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    • 2015
  • A refined higher-order shear deformation theory for bending, vibration and buckling analysis of functionally graded sandwich plates is presented in this paper. It contains only four unknowns, accounts for a hyperbolic distribution of transverse shear stress and satisfies the traction free boundary conditions. Equations of motion are derived from Hamilton's principle. The Navier-type and finite element solutions are derived for plate with simply-supported and various boundary conditions, respectively. Numerical examples are presented for functionally graded sandwich plates with homogeneous hardcore and softcore to verify the validity of the developed theory. It is observed that the present theory with four unknowns predicts the response accurately and efficiently.

A Repetitive Secretory Protein Gene of A Novel Type in Hydropsyche sp. Is Specially Expressed in the Silk Gland

  • Eun, Jai-Hoon;Goo, Tae-Won;Park, Kwang-Ho;Yun, Eun-Young;Hwang, Jae-Sam;Kang, Seok-Woo;Han, Sung-Sik
    • 한국잠사학회:학술대회논문집
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    • 한국잠사학회 2003년도 International Symposium of Silkworm/Insect Biotechnology and Annual Meeting of Korea Society of Sericultural Science
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    • pp.153-154
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    • 2003
  • Trichoptera, or caddisflies, comprise one of the major aquatic insect orders. Like Lepidoptera, caddisflies are capable of spinning silk from specially modified salivary glands, and the diversity of ways this silk is used probably accounts for the success of the order as a whole. These utilize silk to construct both larval and pupal shelters, often incorporating materials from the environmental among the silk thread. In this study, we try to find and characterize novel type genes that should be translated to major component protein of aquatic silk. (omitted)

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Beijing's Wetland Environment Research Based On RS Technology

  • Gong, Hui-Li;Zhao, Wen-Ji;Zhang, Zhi-Feng
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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    • pp.1304-1306
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    • 2003
  • The absolute area of wetland accounts for 0.3% of the whole Beijing. We have studied the current environmental situations of Beijing's wetland and the changes in the key wetland supported by Remote Sensing(RS) technology. The result shows that the areas of wetland are reducing year by year and the quality of ecological environment is dropping year by year. At last, we analyze the factors that influence the change of wetland and propose some constructive suggestions according to current problems existing in Beijing's wetland.

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국토개발측면에서 구상해본 한국의 "내륙운하"건설 (The Land Canal Construction of Korea in the Vision of the National Land Development)

  • 정무용
    • 기술사
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    • 제39권6호
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    • pp.51-56
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    • 2006
  • The important role of canal is moving goods and the canals from all over the world has contributed much to method of transporting goods. But, the canal system accounts rfor 25% of the total moving goods. One of its main goals is to reduce overland transportation costs were 30% more expensive than moving goods over water. We plan to build a Korea inland canal system and need to from a scheme of building a multi canal. We should consider positive aspect of this plan, on the other hand a study of the conal's environmental impact is required prior to beginning any construction. Finally, offer our opinion on the vision of Korea inland canal that aspect5 of national land development.

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Common and Domain-Specific Cognitive Characteristics of Gifted Students: A Hierarchical Structural Model of Human Abilities

  • Song, Kwang-Han
    • 한국영재학회:학술대회논문집
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    • 한국영재학회 2005년도 춘계학술대회
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    • pp.173-180
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    • 2005
  • The purpose of this study was to identify common and domain-specific cognitive characteristics of gifted students based on a hierarchical structural model of human abilities. This study is based on the premise that abilities identified by tests can appear as observable characteristics in test or school situations. Abilities proposed by major models of intelligence were reviewed in terms of their power to explain cognitive characteristics of gifted students. However, due to the lack of their explanatory power and disagreement on common and domain-specific cognitive abilities, a new hierarchical structural model was conceptualized in a unique way based on interrelationships between abilities proposed by the models. The newly established model hypothesizes a cognitive mechanism that accounts for how domain-specific knowledge is formed, as well as which abilities are common and domain-specific, how they are related functionally, and how they account for common and domain-specific cognitive characteristics of gifted students. The cognitive mechanism has important implications for our understanding of the chronically controversial concepts, 'intelligence' and 'knowledge.' Clearer definitions of what intelligence is (g or multiple), what knowledge is, and how knowledge develops ('genetic or environmental,' 'rationalistic or empiricist') may result from this model.

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Analysis of RC walls with a mixed formulation frame finite element

  • Saritas, Afsin;Filippou, Filip C.
    • Computers and Concrete
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    • 제12권4호
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    • pp.519-536
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    • 2013
  • This paper presents a mixed formulation frame element with the assumptions of the Timoshenko shear beam theory for displacement field and that accounts for interaction between shear and normal stress at material level. Nonlinear response of the element is obtained by integration of section response, which in turn is obtained by integration of material response. Satisfaction of transverse equilibrium equations at section includes the interaction between concrete and transverse reinforcing steel. A 3d plastic damage model is implemented to describe the hysteretic behavior of concrete. Comparisons with available experimental data on RC structural walls confirm the accuracy of proposed method.

Optimal design using genetic algorithm with nonlinear elastic analysis

  • Kim, Seung-Eock;Song, Weon-Keun;Ma, Sang-Soo
    • Structural Engineering and Mechanics
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    • 제17권5호
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    • pp.707-725
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    • 2004
  • An optimal design method with nonlinear elastic analysis is presented. The proposed nonlinear elastic method overcomes the drawback of the conventional LRFD method that accounts for nonlinear effect by using the moment amplification factors of $B_1$ and $B_2$. The genetic algorithm used is a procedure based on Darwinian notions of survival of the fittest, where selection, crossover, and mutation operators are employed to look for high performance ones among sections in the database. They are satisfied with the constraint functions and give the lightest weight to the structure. The objective function taken is the total weight of the steel structure and the constraint functions are strength, serviceability, and ductility requirement. Case studies of a planar portal frame, a space two-story frame, and a three-dimensional steel arch bridge are presented.

Sustainable Design and Its Cost: Case Study of Nanning China Resources Tower

  • Lai, Stephen Y.F.
    • 국제초고층학회논문집
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    • 제6권4호
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    • pp.323-326
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    • 2017
  • Sustainability is becoming more and more important in our everyday lives. Thus, it is apparent that more sustainable initiatives are incorporated in a building design concept to reduce operation costs and environmental impacts. However, will the construction cost go up if the building is going green - especially if it is a tall building? This is the question on everyone's mind. In the following paragraphs, we will look into a case study of a skyscraper in Nanning, China. That 411-metre skyscraper, Nanning China Resources Centre East Office Tower, is currently under construction. Designed to LEED-CS Gold standards, the building has adopted a number of sustainable design elements and operation practice, which indeed only accounts for a small percentage of the total construction cost.

Estimating the Heat Island Development Using Landsat TM and AMeDAS Data

  • Harada, Ippei;M.A., Mohammed Aslam;Kondoh, Akihiko
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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    • pp.450-452
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    • 2003
  • In the present investigation, an estimation of the growth of heat island development of Tokyo metropolis which accounts nearly 100 sq. km of areal spread has been carried out. Band 6 data of LANDSAT TM (Thematic Mapper) data acquired on August 1984 and 1994 have been used for estimating the expansion of the heat island development. Since the vegetation decrease is usually associated with the heat island development, a ratio of green covering has also been assessed using TM data. In order to establish the relationship with the air temperature, AMeDAS(Automated Meteorological Data Acquisition System) data have been correlated.

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Bacterial Community Structure and the Dominant Species in Imported Pollens for Artificial Pollination

  • Kim, Su-Hyeon;Do, Heeil;Cho, Gyeongjun;Kim, Da-Ran;Kwak, Youn-Sig
    • The Plant Pathology Journal
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    • 제37권3호
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    • pp.299-306
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    • 2021
  • Pollination is an essential process for plants to carry on their generation. Pollination is carried out in various ways depending on the type of plant species. Among them, pollination by insect pollinator accounts for the most common. However, these pollinators have be decreasing in population density due to environmental factors. Therefore, use of artificial pollination is increasing. However, there is a lack of information on microorganisms present in the artificial pollens. We showed the composition of bacteria structure present in the artificial pollens of apple, kiwifruit, peach and pear, and contamination of high-risk pathogens was investigated. Acidovorax spp., Pantoea spp., Erwinia spp., Pseudomonas spp., and Xanthomonas spp., which are classified as potential high-risk pathogens, have been identified in imported pollens. This study presented the pollen-associated bacterial community structure, and the results are expected to be foundation for strengthening biosecurity in orchard industry.