• Title/Summary/Keyword: Capacity of use

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Experimental study on shear capacity of circular concrete filled steel tubes

  • Xiao, Congzhen;Cai, Shaohuai;Chen, Tao;Xu, Chunli
    • Steel and Composite Structures
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    • v.13 no.5
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    • pp.437-449
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    • 2012
  • Concrete filled steel tube (CFST) structures have recently seen wide use in China, but studies of the shear problem of CFST are inadequate. This paper presents an experimental study on the shear capacity of circular concrete filled steel tube (CCFT) specimens with and without axial compression force. Shear capacity, ductility, and damage modes of CCFTs were investigated and compared. Test results revealed the following: 1) CCFTs with a small shear span ratio may fail in shear in a ductile manner; 2) Several factors including section size, material properties, shear span ratio, axial compression ratio, and confinement index affect the shear capacity of CCFTs. Based on test results and analysis, this paper proposes a design formula for the shear capacity of CCFTs.

Effects of Ti on Mechanical Property and Damping Capacity in Hot-rolled Fe-17%Mn Alloy (열간압연한 Fe-17wt%Mn 합금의 기계적 성질과 진동감쇠능에 미치는 티타늄 첨가의 영향)

  • Kim, Tai-Hoon;Kim, Jung-Chul
    • Journal of Korea Foundry Society
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    • v.29 no.2
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    • pp.59-63
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    • 2009
  • Effects of Ti on damping capacity and mechanical properties are investigated in hot rolled Fe-17%Mn alloy. The existing damping alloy with Fe-Mn binary system was limited the use by high production cost, however in case of using scrap iron instead of pure iron although the content of carbon is higher it is possible to be applied wider field especially construction items because the production cost is lower. However, the excellent specific damping capacity is dropped due to the high content of carbon, we developed advanced type of damping alloy included Ti. TiC is formed with added Ti and it holds the specific damping capacity similar to existing damping alloy. The effect of Ti on damping capacity is found to be beneficial in carbon-containing alloy, which is attributed to the depletion of carbon solute due to the formation of TiC.

Recreation Ecology and Visitor Carrying Capacity Management: Implications for Protected Areas in East Asia

  • Leung, Yu-Fai;Lee, Ju-Hee
    • The Korean Journal of Ecology
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    • v.26 no.2
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    • pp.53-58
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    • 2003
  • Ever-growing recreation, tourism and ecotourism worldwide have become a significant factor of resource degradation in many protected areas. Managers of these areas are increasingly challenged to implement policies, strategies and actions that would protect the resource base while providing quality visitor experience. One major issue in managing protected area visitations is that of carrying capacity, or the question of "how much use is too much\ulcorner". Scientific studies of visitor impacts, often known as recreation ecology, has generated a knowledge base that provides valuable input to the visitor carrying capacity management process adopted by the U.S. National Park Service. This paper aims at (a) providing an overview of recreation ecology research and its application in managing visitor carrying capacity, and (b) examining the relevance of recreation ecology to East Asian protected areas with special reference to the visitor capacity issue.ity issue.

The electrochemical properties of hybrid carbon as a negative active material for lithium ion batteries (리튬이온전지용 음극 활물질 하이브리드형 탄소의 전기화학적 특성)

  • Yang, Dong-Bok;Park, Yong-Pil
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2004.04a
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    • pp.27-30
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    • 2004
  • Different types of hybrid negative materials on pitch based carbon and natural graphite for lithium ion batteries were studied. Two types of active materials were prepared, that is, pitch based graphite carbon, and pitch based carbon impregnating natural graphite. The specific capacity, capacity recovery in high temperature condition, and other electrochemical properties were achieved for these materials. We found that addition of natural graphite type to the pitch based carbon can significant1y improve the specific capacity and interfacial resistance. However, use of natural graphite will cause a serious capacity loss in the high temperature condition owing to its increasing interface resistance. The specific capacity ranged from 321 to 348 mAh/g and the maximum specific capacity was obtained in the case of pitch based carbon impregnating natural graphite.

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A Study on Low Power Algorithm for Battery residual capacity and a Task (배터리 잔량과 태스크에 따른 저전력 알고리즘 연구)

  • Kim, Jae Jin
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.9 no.1
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    • pp.53-58
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    • 2013
  • In this paper, we proposed low power algorithm for battery residual capacity and a task. Algorithm the mobile devices power of the battery residual capacity for the task to perform power consumption to reduce the frequency alters. Task is different in power consumption according to kinds of in time accomplishment device to use. Adjustment of power consumption analyzes kinds of given tasks from having the minimum power consumption task to having the maximum power consumption task. Control frequency so that power consumption waste to be exposed to battery residual capacity can be happened according to the results analyzed. Experiment the frequency by adjusting power consumption a method to reduce using [7] and in the same environment power of the battery residual capacity consider the task to perform frequency were controlled. Efficiency was proved compare with the experiment results [7]. The experiments results show increment in the number of processing by 45.46% comparing with that [7] algorithm.

A Development of Environmental Capacity Estimation Model Using the National Environmental Assessment Indicators (국토환경성평가 지표를 이용한 환경용량 산정모델 개발)

  • Lee, Chong-Soo;Lee, Woo-Kyun;Jeon, Seong-Woo
    • Journal of Environmental Impact Assessment
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    • v.15 no.6
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    • pp.385-394
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    • 2006
  • Land resources should be managed not only for human utilizations but also for environmental preservation. Based on that, environmental capacity should be estimated in both environmental and developmental ways. This study was performed for developing an estimation model for relative environmental capacity, considering both Development Tolerance Index(DTI), which shows environmental and ecological conservation value and is based on national environmental assessment indicators of the Korea Ministry of Environment, and Development Attractiveness Index(DAI), which shows topographical characteristics and geographical accessibility. The relative environmental capacity in this study can be helpful to coping with the conflict in planning and managing the use of land resources. The relative environmental capacity in this study, however, did not include either environmental or ecological sensitivity of land resources. This limitation should be solved through further research.

The Effect of Internet Neutrality Regulation on Social Welfare Considering Network Congestion and Investment Incentive (혼잡효과와 망투자유인을 고려한 인터넷망 중립성 규제의 경제적 효과분석)

  • Jung, Choong Young;Jung, Song Min
    • Journal of Information Technology Applications and Management
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    • v.20 no.3_spc
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    • pp.201-217
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    • 2013
  • This paper analyzes the effect of network neutrality regulation on social welfare using the two-sided market under the network congestion. This paper deals with zero price rule regulation which means the price regulation on the side of content. The results are as follows : First, under the monopoly platform, internet use price, contents price, and the number of internet user and content provider are all decreasing as the network congestion increases. Second, under the monopoly platform internet use price, contents price, and the number of internet user and content provider are all increasing as the network capacity increases. Third, the price of internet use and contents internet use which maximize social welfare are increasing and the number of internet user and content provider are decreasing as the network congestion increases. Fourth, optimal network capacity for monopoly platform provider is less than socially optimal network capacity. Fifth, if network neutrality regulation is enforced, the price of internet use is higher than monopoly platform provider and the price of contents is lower than monopoly platform provider. Also, the number of internet user is less than monopoly platform provider and the number of content provider is more than that. By the way, when network congestion increases, internet use price, the number of internet user, and the number of content provider are decreasing. Sixth, network neutrality regulation is more effective for internet user side than contents provider when network congestion is considered. This means that network neutrality regulation is not effective for contents market side when network congestion is seriously large.

Evaluation of the seismic Capacity of Existing Concrete Gravity Dams (기존 콘크리트 증력식 댐 내진성능 평가)

  • 소진호;김용곤;정영수
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 2001.09a
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    • pp.216-223
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    • 2001
  • The necessity of the seismic capacity evaluation of existing concrete gravity dams i: through the Izmit, Turkey and JiJi, Taiwan earthquake in 1999. In this study, the method seismic capacity evaluation of existing concrete gravity dams in U.S. A., Japan and Canada reviewed, applied them to the concrete gravity dam in use. Evaluation of the seismic ca approach using three levels that are level 1 - Screening, level 2 - Pseudostatic Metho level 3 - Dynamic Analysis, Method.

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Bearing Capacity of Geogrid-Reinforced Railroad Ballast (지오그리드로 보강된 철도노반 쇄석기층의 지지력에 관한 연구)

  • 신은철;김두환;이규진;이상조
    • Proceedings of the KSR Conference
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    • 1999.05a
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    • pp.367-374
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    • 1999
  • The selection of geogrid types for the use of reinforced rail roadbed is important in the design of railways. Also, the problem of the construction damage on the geogrid during construction is raised by the field engineers. Therefore, laboratory model tests were peformed to investigate the efficiency of the bearing capacity and construction damage. As a result, it was found that the bearing capacity of the rigid geogrid reinforced railroad ballast shows 1.54 times higher than that of the flexible geogrid reinforced case. In addition, there were no noticeable damage during construction.

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Application of a New Reliability Index in Transmission Pricing (송전요율 결정을 위한 새로운 신뢰도 지수 산정에 관한 연구)

  • Lee, Won-Goo;Kim, Bai-Ho H.
    • Proceedings of the KIEE Conference
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    • 1999.11b
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    • pp.213-215
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    • 1999
  • This paper presents a transmission cost allocation through application of a new reliability index in transmission pricing in competitive electric industry. The proposed method allocates a fair use of transmission system charge given separately to individual generator by capacity usage, based on the contribution of individual generator considering N-1 contingency in reliability margin of transmission capacity, and offers more alternatives of pricing in using transmission capacity and transmission margin.

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