• Title/Summary/Keyword: research structure

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Population genetic structure based on mitochondrial DNA analysis of Ikonnikov's whiskered bat (Myotis ikonnikovi-Chiroptera: Vespertilionidae) from Korea

  • Park, Soyeon;Noh, Pureum;Choi, Yu-Seong;Joo, Sungbae;Jeong, Gilsang;Kim, Sun-Sook
    • Journal of Ecology and Environment
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    • v.43 no.4
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    • pp.454-461
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    • 2019
  • Background: Ikonnikov's whiskered bat (Myotis ikonnikovi) is found throughout the Korean Peninsula, as well as in Kazakhstan, Russia, Mongolia, China, and Japan. It is small-sized and primarily inhabits old-growth forests. The decrease and fragmentation of habitats due to increased human activity may influence the genetic structure of bat populations. This study was designed to elucidate the population genetic structure of M. ikonnikovi using mitochondrial genes (cytochrome oxidase I and cytochrome b). Results: The results showed that M. ikonnikovi populations from Korea have high genetic diversity. Although genetic differentiation was not detected for the COI gene, strong genetic differentiation of the Cytb gene between Mt. Jeombong and Mt. Jiri populations was observed. Moreover, the results indicated that the gene flow of the maternal lineage may be limited. Conclusions: This study is the first to identify the genetic population structure of M. ikonnikovi. We suggest that conservation of local populations is important for sustaining the genetic diversity of the bat, and comprehensive studies on factors causing habitat fragmentation are required.

The Analysis of Metallurgical Structure and Arc Properties of Copper Wire Due to Over-current (과전류에 의한 동 전선의 용단 아크 특성 및 금속조직 분석)

  • Kim, Young-Seok;Shong, Kil-Mok;Kim, Dong-Ook;Lee, Ki-Yeon;Choi, Chung-Seog
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2005.07a
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    • pp.554-555
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    • 2005
  • In this paper, we analyzed a metallurgical structure and arc properties of copper wire when the over-current flows on electric wire. From the results, The fusing current was related to the fusing time(current rising rate per second). In case of the shorter the fusing time, the fusing current was high, and the fusing time of ac type was larger than that of dc type. The copper wire was bent by the increase of current and heated, the beads were scattered around wire with a flash. We could observed the dendrite structure in 'molten wire at ac and dc current type. According as the current rising rate per second is short, the dendrite structure is distributed in surface of wire.

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Temperature Dependence of Bonding Structure of GZO Thin Film Analyzed by X-ray Diffractometer (XRD의 결정구조로 살펴본 GZO 박막의 온도의존성)

  • Oh, Teresa
    • Journal of the Semiconductor & Display Technology
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    • v.15 no.1
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    • pp.52-55
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    • 2016
  • GZO film was prepared on p-type Si wafer and then annealed at various temperatures in an air conditions to research the bonding structures in accordance with the annealing processes. GZO film annealed in an atmosphere showed the various bonding structure depending on annealing temperatures and oxygen gas flow rate during the deposition. The difference of bonding structures of GZO films made by oxygen gas flows between 18 sccm and 22 sccm was so great. The bonding structures of GZO films made by oxygen gas flow of 18 sccm were showed the crystal structure, but that of 22 sccm were showed the amorphous structure in spite of after annealing processes. The bonding structure of GZO as oxide-semiconductor was observed the trend of becoming amorphous structures at the temperature of $200^{\circ}C$. Therefore, the characteristics of oxide semiconductor are needed to research the variation near the annealing at $200^{\circ}C$.

Nonlinear Wave Transformation of a Submerged Coastal Structure (잠수구조물에 의한 비선형파랑변형에 관한 연구)

  • Kim, W. K.;Kang, I. S.;Kwak, K. S.;Kim, D. S.
    • Journal of Korean Port Research
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    • v.8 no.1
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    • pp.41-47
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    • 1994
  • The present paper discusses the nonlinear wave deformation due to a submerged coastal structure. Theory is based on the frequency-domain method using the third order perturbation and boundary integral method. Theoretical development to the second order perturbation and boundary integral method. Theoretical development to the second order Stokes wave for a bottom-seated submerged breakwater to the sea floor is newly expanded to the third order for a submerged coastal structure shown in Figure 1. Validity is demonstrated by comparing numerical results with the experimental ones of a rectangular air chamber structure, which has the same dimensions as that of this study. Nonlinear waves become larger and larger with wave propagation above the crown of the structure, and are transmitted to the onshore side of the structure. These characteristics are shown greatly as the increment of Ursell number on the structure. The total water profile depends largely on the phase lag among the first, second and third order component waves.

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Lateral seismic response of building frames considering dynamic soil-structure interaction effects

  • RezaTabatabaiefar, S. Hamid;Fatahi, Behzad;Samali, Bijan
    • Structural Engineering and Mechanics
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    • v.45 no.3
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    • pp.311-321
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    • 2013
  • In this study, to have a better judgment on the structural performance, the effects of dynamic Soil-Structure Interaction (SSI) on seismic behaviour and lateral structural response of mid-rise moment resisting building frames are studied using Finite Difference Method. Three types of mid-rise structures, including 5, 10, and 15 storey buildings are selected in conjunction with three soil types with the shear wave velocities less than 600m/s, representing soil classes $C_e$, $D_e$ and $E_e$, according to Australian Standard AS 1170.4. The above mentioned frames have been analysed under two different boundary conditions: (i) fixed-base (no soil-structure interaction), and (ii) flexible-base (considering soil-structure interaction). The results of the analyses in terms of structural lateral displacements and drifts for the above mentioned boundary conditions have been compared and discussed. It is concluded that the dynamic soil-structure interaction plays a considerable role in seismic behaviour of mid-rise building frames including substantial increase in the lateral deflections and inter-storey drifts and changing the performance level of the structures from life safe to near collapse or total collapse. Thus, considering soil-structure interaction effects in the seismic design of mid-rise moment resisting building frames, particularly when resting on soft soil deposit, is essential.

Policy research and energy structure optimization under the constraint of low carbon emissions of Hebei Province in China

  • Sun, Wei;Ye, Minquan;Xu, Yanfeng
    • Environmental Engineering Research
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    • v.21 no.4
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    • pp.409-419
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    • 2016
  • As a major energy consumption province, the issue about the carbon emissions in Hebei Province, China has been concerned by the government. The carbon emissions can be effectively reduced due to a more rational energy consumption structure. Thus, in this paper the constraint of low carbon emissions is considered as a foundation and four energies--coal, petroleum, natural gas and electricity including wind power, nuclear power and hydro-power etc are selected as the main analysis objects of the adjustment of energy structure. This paper takes energy cost minimum and carbon trading cost minimum as the objective functions based on the economic growth, energy saving and emission reduction targets and constructs an optimization model of energy consumption structure. And empirical research about energy consumption structure optimization in 2015 and 2020 is carried out based on the energy consumption data in Hebei Province, China during the period 1995-2013, which indicates that the energy consumption in Hebei dominated by coal cannot be replaced in the next seven years, from 2014 to 2020, when the coal consumption proportion is still up to 85.93%. Finally, the corresponding policy suggestions are put forward, according to the results of the energy structure optimization in Hebei Province.

A Study on the Space Structure of School Health Room - From the Review About the Status of Space Structure of Remodeled School Health Rooms - (학교 보건실의 공간구성에 관한 기초연구 - 리모델링된 보건실의 공간구성 현황 분석 -)

  • Choi, Byoung-Kwan;Rieu, Ho-Seop
    • Journal of the Korean Institute of Educational Facilities
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    • v.15 no.1
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    • pp.34-43
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    • 2008
  • The purpose of the study is to provide design guidelines and space structure of health rooms for elementary and middle schools. In order to do that, with the subject of health teachers from 96 schools in Seoul city, which remodeled the health rooms in 2005 and 2006, the research was carried out. Through the research, we organized the collected opinions and current situation about the procedures of the promotion, size, location and space formation. Based on that, we could acquire a better grasp of a type of space structure for the guidelines. From the research, we realized that in terms of location, size, and internal space structure, it has been improved compared to the past. However, we also saw more rooms for improvements in the coming future. We believe that such result will be utilized as the basic information for the roadmap of new space structure of health rooms at current schools and new schools.