• Title/Summary/Keyword: Height Of Ground

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Hybrid Planar Inverted-F Antenna with a T-Shaped Slot on the Ground Plane

  • Jeon, Sin-Hyung;Choi, Hyeng-Cheul;Kim, Hyeong-Dong
    • ETRI Journal
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    • v.31 no.5
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    • pp.616-618
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    • 2009
  • In this letter, a novel hybrid planar inverted-F antenna (PIFA) with a T-shaped slot on the ground plane is proposed. The loop structure formed by the feed line and shorting pin can be operated as a series and shunt inductance for the PIFA and the T-shaped slot antenna, respectively. The PIFA operates at a frequency of 1.75 GHz, while the T-shaped slot on the ground plane operates at 2.4 GHz by the same voltage feeding source. The height of the PIFA is 6.5 mm, and the size of an upper patch is designed to be 30 mm${\times}$16 mm. The measured relative impedance bandwidth of the PIFA and the T-shaped slot are about 12% and 21%, respectively. In addition, good antenna performance was achieved.

A Study on the Correlation of Growth Factors in Phyllostachys Reticulata Kock and Phyllostachys Edulis Riv by Each site (지위별(地位別) 왕죽(王竹) 및 맹종죽(孟宗竹)에 있어서 생장인자(生長因子)의 상관관계(相關關係)에 대(對)한 연구(硏究))

  • Kim, Chang Soo;Chung, Young Gwan
    • Journal of Korean Society of Forest Science
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    • v.8 no.1
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    • pp.11-16
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    • 1968
  • 1. A Study was to delineate the correlation relationship growth factors, a) height and clear-length, b) height and circle of breast height, c) height and circle of ground height, d) height and crown length, of phyllostachys reticulata kock and phyllostachys edulis riv, 2. The formula applied to arrive at correlation coefficient according to correlation table, was $e=\frac{1-{\mu}^2}{\sqrt{\Sigma}X^2y^2}$ the formula for average error was $e=0.6745\frac{1-{\mu}^2}{\sqrt{n}}$ 3. The correlation coefficient and average error by each species were as three tables. 4. Area of the sample plot were 0.5~1 acres. 5. Height, clear-length, circle of breast height, circle of ground height and crown-length of bamboos were measured by weise hypsometer and pole.

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Seismic behavior of special moment-resisting frames with energy dissipating devices under near source ground motions

  • Bayat, Mahmoud;Bayat, Mahdi
    • Steel and Composite Structures
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    • v.16 no.5
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    • pp.533-557
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    • 2014
  • In this study, the performances of the SMRF building equipped with energy dissipating devices are studied. Three types of these structures with different heights are considered. The Added Damping and Stiffness (ADAS) devices are used as energy dissipating devices in these structures. The behavior of these structures with ADAS devices subjected to near source ground motions are investigated. Three SMRF buildings with five, ten and fifteen-story, with ADAS devices were chosen. The nonlinear time history analysis was used by applying the near source ground motions with PERFORM 3D.V4 and conclusions are drawn upon an energy criterion. The effect of PGA variation and height of the frames are also considered based on the energy criterion.

Seismic Capacity Required for the Safety Limit Design of High-rise RC Buildings under Long-period Ground Motions in Osaka, JAPAN and its Estimation Based on the Equivalent Linearization Method

  • Sanada, Yasushi;Yoshida, Hiroki;Awano, Masayuki
    • International Journal of High-Rise Buildings
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    • v.9 no.4
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    • pp.315-323
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    • 2020
  • In June 2016, the Ministry of Land, Infrastructure, Transport and Tourism (MLIT) in Japan delivered countermeasures against long-period ground motions caused by strong earthquakes along the Nankai trough. However, the countermeasures do not cover high-rise buildings equal to or shorter than 60 m in height, which do not require earthquake response analyses in the seismic design. Hence, in the present study, earthquake response analyses for such high-rise reinforced concrete (RC) buildings were performed under artificial ground motions assumed in the OS1 and OS2 regions to determine the base shear coefficients that satisfy a given safety demand. Furthermore, the results from the earthquake response analyses were estimated by the authors' proposed method based on the equivalent linearization method, showing good agreement and inspiring suggestions for more accurate and simplified estimations.

Aerodynamic Load Analysis for Wind Turbine Blade in Uniform Flow and Ground Shear Flow (균일 흐름과 지상 전단 흐름에 놓인 수평축 풍력터빈 블레이드의 공력 하중 비교)

  • Kim, Jin;Ryu, Ki-Wahn
    • 한국신재생에너지학회:학술대회논문집
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    • 2007.11a
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    • pp.387-390
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    • 2007
  • Recently the diameter of the 5MW wind turbine reaches 126m, and the tower height is nearly the same with the wind turbine diameter. The blade will experience periodic inflow oscillation due to blade rotation inside the ground shear flow region, that is, the inflow velocity is maximum at uppermost position and minimum at lowermost position. In this study we compare the aerodynamic data between two inflow conditions, i.e, uniform flow and normal wind profile. From the computed results all of the relative errors for oscillating amplitudes increased due to the ground shear flow effect. Especially My at hub and $F_x$, $M_y$, $M_z$ at LSS increased enormously. It turns out that the aerodynamic analysis including the ground shear flow effect must be considered for fatigue load analysis.

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Comparison Analysis of Lower Extremities Activity while Walking Downhill according to the Height of Heel for Women in 20's

  • Kim, Hyeun-Ae;Kim, Hee-Tak
    • Journal of International Academy of Physical Therapy Research
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    • v.2 no.2
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    • pp.324-328
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    • 2011
  • The purpose of this study is to measure the effect of change in heel height on lower extremities activity of young women on high-heeled shoes that young women prefer from more kinetic and realistic perspective as this study changes the degree of slope on a treadmill. The study subjects are 15 young and healthy women who do not have any external injuries or problem with walking and understand the purpose of this study clearly. They wore three different height of heels(1cm, 7cm, 12cm) and walked on a treadmill at a constant speed of 3km/h. EMG value of four muscles (anterior tibial muscle, gastrocnemius muscle, straight muscle of thigh, and biceps muscle of thigh) were collected when walking and the change according to the height of heels were analyzed using one-way ANOVA. Multiple comparison analysis on anterior tibial muscle and heel height showed that the group with 12cm heel showed significantly high muscle activation compared to the groups with 1cm and 7cm heels. The result of this study can be used for various perspectives from inferring and mediating problems caused by wearing high heels on different ground slopes for a long time.

Relation between crown-length, tree-height, diameter Clear-bale length and the longest branch length in a Pinus densiflora stand (적송림(赤松林)에 있어서의 성장인자간(成長因子間)의 상관(相關))

  • Yim, Kyong Bin;Pack, Myong Kyu
    • Journal of Korean Society of Forest Science
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    • v.5 no.1
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    • pp.27-32
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    • 1966
  • Taking an opportunity of the application of clearcutting method, 140 red pine (Pinus densiflora Sieb. et Zucc.) trees grown at Chon-nam province, the southern part of South Korea, were fellen and the tree height, clear-bole length, D.B.H. diameter at base(0.2m above from the ground line) and the length of the longest branch were measured. The correlation between factors mentioned were analysed. The results are summarized as follows: 1. The correlation between crown length and tree height (r=0.821) was sinificant. 2. The correlation between the diameter at base and D.B.H. was highly significant (r=0.961). D.B.H. can be calculated from multiplying the diameter at base by 0.88. 3. A weak relation between D.B.H and tree height was abserved. 4. The positive correlation between tree height and clear-bole-length was calculated, but it was not sharp between D.B.H. and the length of the longest branch. 5. The height, basal area, D.B.H. and volume increment by tree class calculated from the data of the stem analysis are presented (Tab. 3~10).

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Extraction of Building Height Using Digital Map and Single Imagery (수치지도와 단영상을 이용한 건물의 고도값 추출)

  • Yun Kong-Hyun
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.24 no.1
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    • pp.57-64
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    • 2006
  • Recently the extraction of building height information has been investigated using remotely sensed image and digital maps. In this study, based on the digital photogrammetry principle and mono imagery method the building height information can be extracted by using relationship between ground coordinates and image coordinates. To evaluate the result the comparison was done with building height from 1:5000 aerial photo. The experiment shows that extraction of building height could be performed using IKONOS single imagery and digital map and it is proved that the building height could be reconstructed within some extent.

Extraction of Building Height Using correlation of Digital Map and Single Imagery (단영상과수치지도의상관관계를이용한건물의고도값추출)

  • Yeu Bock-Mo;Hong Jea-Min;Kim Min-Gu
    • Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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    • 2006.05a
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    • pp.138-145
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    • 2006
  • Recently the extraction of building height information has been investigated using remotely sensed image and digital maps. In this study, based on the digital photogrammetry principle and mono imagery method the building height information can be extracted by using relationship between ground coordinates and image coordinates, To evaluate the result the comparison was done with building height from 1:5000 aerial photo. The experiment shows that extraction of building height could be performed using IKONOS single imagery and digital map and it is proved that the building height could be reconstructed within some extent.

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An Analytical Study on the Determination of the Lowest Improvement Depth of Deep Mixing Method (심층혼합공법의 최저 개량 심도 결정에 관한 해석적 연구)

  • Park, Choon-Sik;Song, Ji-Won
    • Journal of the Korean Geosynthetics Society
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    • v.19 no.1
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    • pp.35-44
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    • 2020
  • Design techniques for the deep mixing method, one of the soft ground improvement methods, include two ways to interpret the ground as composite ground and pile ground. However, since comparative studies on these two approaches are insufficient, it is difficult to clearly define the analysis criteria in the design. In this study, two-dimensional and three-dimensional analyses have been performed with different conditions. The three conditions, the embankment height, depth of soft ground, and replacement ratio of reinforcement zones were varied and the analysis was performed on the basis of the assumption of composite ground and pile ground for each condition. As a result, the minimum depth of improvement in the two-dimensional analysis was deeper by 6.85~9.08% than in the three-dimensional analysis. The pile ground analysis showed that the depth of improvement was deeper by 12.22~14.45% than the composite ground analysis. Based on these results, it is concluded that for more accurate design, three-dimensional analysis should be performed rather than two-dimensional analysis. also, it is judged that necessary to analyze the ground as composite ground for economical design, and as the pile ground analysis for stable design.