• Title/Summary/Keyword: area reduction

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The Spatial and Social Characteristics of the Farmland Reduction Area in Urban Vicinity - Focusing on Gimhae City in Gyeongsangnamdo - (도시주변 농지감소지역의 공간 및 사회적 특성 - 경상남도 김해시를 중심으로 -)

  • Lee, Seung-Hye;Lee, Yoo-Jick
    • Journal of Korean Society of Rural Planning
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    • v.24 no.1
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    • pp.99-111
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    • 2018
  • This study was conducted for the purpose of deriving implications by observing the changing patterns and characteristics of the farmland reduction area in urban vicinity with Gimhae city, Gyeongsangnam-do as the subject. In order to achieve this goal, we first examined the problems and possibilities of farmland reduction area in urban vicinity through a theoretical review. Additionally, the characteristics of land use and community were examined for Gimhae city, Gyeongsangnam-do. The results of the study are summarized as follows. First, for 35 years from 1981 to 2015, Gimhae decreased $50.52km^2$ of farmland, which is about 17.4 times that of Yoido, and about 69.4% of the decreased farmland area. Second, the decrease in agricultural land has been expanding to the whole of Gimhae City from 1990 to 2010, and has been continuing since 2010 around dong-area. Third, in the farmland reduction area in urban vicinity, the number of settlements increases rapidly, but the aging population also increases. Fourth, the composition of the community is getting complicated with the change of the members. Taken together, it is necessary to manage the area efficiently because rapid change is present in the farmland reduction area in urban vicinity. Based on this, the implications are summarized as follows. First, there is a change in land use due to the reduction of farmland not designated as agricultural development region. Therefore, it is necessary to supplement the farmland-conversion standard. Second, despite the fact that land use management has been carried out, there have been problems such as uncontrolled development due to the development pressure beyond institutional management, and therefore it is necessary to improve the structural defects of the pertinent legal system. Fourth, while the traditional farming activities are decreasing with the decrease of agricultural land area, the increase in farms with secondary jobs and the urban-rural interchanges organization's efforts can lead to increased visits from outsiders that seek rural tourism and experiential learning.

Damage Assessment of Reinforced Concrete Beams using Damage-area concept (손상영역을 이용한 철근 콘크리트 보의 손상평가)

  • Roh, Won-Kyoun;Shim, Chang-Su;Kim, Ki-Bong;Kim, Hyun-Ho;Hong, Chang-Kuk
    • Proceedings of the Korea Concrete Institute Conference
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    • 2004.11a
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    • pp.647-650
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    • 2004
  • This paper deals with the damage assessment of the concrete beam using Damage-area concept and the modulus of elasticity reduction of the beam was evaluated. Simply supported concrete beams were loaded at the mid-span. When the displacements from the tests were increased more than $10\%$ of the initial values, flexural cracks occured. Judging from the observed cracks, damaged area of the beams were assumed and the modulus of elasticity reduction using the smeared-cracking concept was estimated to minimize the error between the test results and analytical results. Main parameters for the assessment were height of the crack area, length of the crack area, position of the crack area and the modulus of elastic reduction ratio. In each stage, damaged elements and their stiffness reduction were estimated to minimized the error.

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Sensitivity analysis of effective imperviousness estimation for small urban watersheds (도시 소유역 유효불투수율의 민감도 분석)

  • Kim, Dae Geun;Ko, Young Chan
    • Journal of Korean Society of Water and Wastewater
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    • v.23 no.2
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    • pp.181-187
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    • 2009
  • In this study, a runoff hydrograph and runoff volume were calculated by using the kinetic wave theory for small urban watersheds based on the concept of low impact development(LID), and the effective imperviousness was estimated based on these calculations. The degree of sensitivity of the effective imperviousness of small watersheds to the impervious to pervious area ratio, infiltration capability, watershed slope, roughness coefficient and surface storage depth was then analyzed. From this analysis, the following conclusions were obtained: The effective imperviousness and paved area reduction factor decreased as the infiltration capability of pervious area increased. As the slope of watersheds becomes sharper, the effective imperviousness and the paved area reduction factor display an increasing trend. As the roughness coefficient of impervious areas increases, the effective imperviousness and the paved area reduction factor tend to increase. As the storage depth increases, the effective imperviousness and the paved area reduction factor show an upward trend, but the increase is minimal. Under the conditions of this study, it was found that the effective imperviousness is most sensitive to watershed slope, followed by infiltration capability and roughness coefficient, which affect the sensitivity of the effective imperviousness at a similar level, and the storage depth was found to have little influence on the effective imperviousness.

Numerical Study on the Process Analysis of Ozone Production due to Emissions Reduction over the Seoul Metropolitan Area (수도권 배출량 저감에 따른 오존 발생 과정 분석에 관한 수치연구)

  • Jeong, Yeo-Min;Lee, Soon-Hwan;Lee, Hwa-Woon;Jeon, Won-Bae
    • Journal of Environmental Science International
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    • v.21 no.3
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    • pp.339-349
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    • 2012
  • In order to clarify the impact of emissions reductions on the air quality over Metropolitan area of Korean Peninsula, several numerical experiment and analysis of integrated process rate(IPR) of ozone were carried out. Numerical models used in this study are WRF for the estimate the meteorological elements and CMAQ for assessment of ozone concentration. As result in the sensitive test of VOC/NOx reduction experiments, although VOC reduction tends to induce the different impact on the advection and photochemical reaction rate of ozone in urban area and rural area, the mechanism of ozone appeared to be more sensitive to the reduction of VOC than that of NOx over the metropolitan and its surround area. So the control of VOC emission inventories is an effective means to decrease the ozone concentrations around this area.

A Study on Runoff Water Reduction Effects According to Shapes of Formation of Artificial Soil Green Area in Multi-Housing Complex (공동주택단지 내 인공지반 녹지조성 형태에 따른 우수유출 저감효과)

  • Nam, Mi A;Jang, Dae Hee;Kim, Hyeon Soo
    • KIEAE Journal
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    • v.13 no.1
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    • pp.9-15
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    • 2013
  • This study aims to analyze, by forming an experimental area of artificial soil green area that is of equal scale and analyzing the characteristics of runoff water in accordance with the cross-section configuration, applied the benefits in an actual multi-housing case study complex. In examining the measurement test results of the runoff water infiltration amount and surface runoff amount of a low-profile type green area(Dish type) and a general type green area(Mound type), Dish type was seen to have 1.5-times higher runoff water infiltration amount than Mound type during heavy rainfalls and showed about a 50% reduction with respect to the surface runoff amount. In other words, artificial soil green area offers the benefit of reduction of surface runoff amount and suggests, in actuality even with a change to the cross-sectional configuration of artificial soil green area alone at the time of construction of multi-housings, the possibility of benefits and reduction of costs spent on existing rainwater management facilities.

Analysis of Copper clad steel wire in the drawing process using FE method (유한요소 해석을 이용한 동피복 복합선재의 인발 공정 해석)

  • Kim H.S.;Jo H.;Jo H. H.;Kim D.K.;Kim B.M.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2004.05a
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    • pp.27-30
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    • 2004
  • Clad wire , which has the advantages of the high strength of a steel core and the electro-conductivity, corrosion resistance of a copper layer, is widely being used the telecommunications, electric-electronic and military technology industries, among others. It is important to obtain uniform coated rate when producing clad wires. Clad wire drawing process can be influenced on damage and coated rate of core and sleeve by process variables as semi-die angle and reduction in area. Therefore, in this study, the finite-element results established in previous study is used to analyze the effect of the various forming parameters, which included the semi-die angle, reduction in area etc. The coated rate will be predicted with observation copper coated rate variation according to total reduction in area and the optimal pass schedule will be set up through proper reduction in area and semi-die angle variation.

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Development of Online Model for Mean Effective Strain, Roll Force and Area Reduction in Bar Rolling with Three Rolls (콕스밀에서 평균변형율, 압하력, 단면감소율에 대한 수식모델개발)

  • Je S. H.;Hwang S. M.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2001.10a
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    • pp.162-165
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    • 2001
  • In industrial practice, caliber design in shape rolling depends on the designer's experience, which in general is obtained through costly trial-and error process. on-line model which is relations of mean effective strain, roll force and area reduction is derived from finite element process simultion in bar rolling with three rolls.

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Study on the size reduction factor of extreme wind pressure of facade cladding of high-rise buildings with square section

  • Xiang Wang;Yong Quan;Zhengwei Zhang;Ming Gu
    • Wind and Structures
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    • v.36 no.1
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    • pp.41-60
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    • 2023
  • The effect of cladding panel size on the size reduction factor (SRF) of extreme area-averaging wind pressure (EAWP) on the facades of a high-rise building is often ignored in previous studies. Based on wind tunnel tests, this study investigated the horizontal and vertical correlations of wind pressure on the facade claddings of square-section high-rise buildings. Then, the influencing parameters on the SRF of the EAWP on the cladding panels were analyzed, which were the panel area, panel width, panel length and building width. The results show clear regional distinctions in the correlation of wind pressures on the building facades and the rules of the horizontal and vertical correlations are remarkably different, which causes the cladding size ratio to impact the SRF significantly. Therefore, this study suggests the use of the non-dimensional comprehensive size parameter b𝜶h1-𝜶/B (𝜶 is the fitting parameter) determined by the cladding panel horizontal size b, cladding panel vertical size h and the building width B rather than the cladding panel area to describe the variation of the EAWP. Finally, some empirical formula for the SRF of the EAWP on the cladding of a high-rise building is proposed with the nondimensional comprehensive size parameter.

A Case of Blasting Vibration Reduction in the Tunnel Construction under a Residential Area (주거지역 터널공사에서의 발파진동 저감사례)

  • Kang, Jin-Ook;Lee, Hyun-Koo;Lee, Myong-Choul
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2007.05a
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    • pp.175-180
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    • 2007
  • This paper presents a case study on blasting vibration reduction in NATM(New Australian Tunnelling Method) tunnel construction carried out under a congested residential area. In NATM tunnel constructions, blasting is an essential process, thus vibration phenomenon is inevitable. Therefore, the vibration reduction was tried to avoid expected complaints from the public living in the area. Test blastings were performed to get the constants for an estimation formula of vibration velocity. Then the influence area was approximated using the estimation formula, and construction methods for the vibration reduction were sought based on the results.

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A Study on the Pollutants Reduction of Venturi Type After-burner by oxygen enrichment and Induced Air (산소부화와 유인공기를 이용한 벤츄리형 후연소기의 오염물질 저감에 관한 연구)

  • 오세원;박준홍;이용후;이진석;이도형
    • Journal of Advanced Marine Engineering and Technology
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    • v.27 no.7
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    • pp.845-851
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    • 2003
  • The purpose of this experimental study is to investigate the quantitative pollutants reduction by oxygen enrichment and induced air effect in venturi type after-burner. For this purpose, CO, $CO_2$, $O_2$. and HC concentrations were measured before and after the after-burner by changing the Oxygen flow rate and area ratio which is defined as the ratio of air inducing area divided by total area. As results of this study, when the area ratio were increased, the emission reduction effect was increased even less oxygen flow rate. In that case when oxygen was injected too little, the pollutants were increased.