• Title/Summary/Keyword: line slope

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Belowground Carbon Allocation of Natural Quercus mongolica Forests Estimated from Litterfall and Soil Respiration Measurements (Litterfall과 토양호흡 측정에 의한 신갈나무 천연림의 지하부 탄소 분배)

  • Yi Myong-Jong;Son Yowhan;Jin Hyun-O;Park In-Hyeop;Kim Dong-Yeop;Kim Yong-Suk;Shin Dong-Min
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.7 no.3
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    • pp.227-234
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    • 2005
  • From published data of mature forests worldwide, Raich and Nadelhoffer suggested that total belowground carbon allocation (TBCA) could be estimated from the difference between annual rates of soil respiration and aboveground litterfall. Here we analyze new measurements of IRGA-based soil respiration and litterfall of natural mature oak forests dominated by Quercus mongolica in Korea. Rates of in situ soil respiration and aboveground litter production are highly and positively correlated. Our results disagree with the Raich and Nadelhoffer model far world forests. A regression analysis of the data from Q. mongolica forests produced the following relationship: annual soil respiration : 141 + 2.08 ${\times}$ annual litterfall. The least squares regression line has a more gentle slope (2.08) than the slope (2.92) described by Raich and Nedelhoffer for mature forests worldwide. The regression slope of our study indicates that, on average, soil respiration is about two times the aboveground litterfall-C, which further implies that TBCA is similar with annual aboveground litterfall-C at natural Q. mongolica forests in Korea. The non-zero Y-intercept (141) of the regression indicates that TBCA may be greater than litterfall-C where litterfall rate are relativery low. Over a gradient of litterfall-C ranging from 200-370 g C $m^{-2}yr^{-l}$, TBCA increased from 350-530 g C $m^{-2}yr^{-l}$.

Studies on the Behaviour of Fish Schools in the Main-net of a Large Scale Set-net Using Scanning Sonar - I - The Behaviour of Small Schools of Sardine Sardinops Melanosticta in the Main-net - (소나 관찰에 의한 대형정치망내 어군행동의 연구 - I - 입망한 정어리소형군의 행동 -)

  • 김문관
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.31 no.1
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    • pp.1-7
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    • 1995
  • The fish behavior survey in the main-net of a large scale-net was carried out in relation to the catching function of the set-net. at Kishihata set-net in Japan during the period from January 29th to February 22th 1992. The results obtained are summarized as follows; 1. The greatest number of schools observation in the main-net occurred between 17 : 00hrs and 18 : 00hrs. after which the schools suddenly disappeared. This result show that the schools did not stay in the main-net. but immediately moved through into the bag-net or left the main-net. 2. The course of movement of the small schools of sardine in the main-net was in a straight line to the slope-net. However. upon arrived at the slope-net the school turned around. away from the slope-net and went directly towards the playground. 3. The majority of small schools of sardine in the main-net were estimated to move with the mode velocity 25cm/sec. however the maximum velocity were recorded 80cm/sec.

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Position Error Analysis of Digital Map for LIS/GIS Database (LIS/GIS의 D/B구축을 위한 수치지도의 위치오차분석에 관한 연구)

  • 조규전;이영진;홍용현
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.15 no.1
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    • pp.1-7
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    • 1997
  • In the digital mapping for data base contruction, the positional information is used as an important tool in LIS/GIS(Land Information System/Geographic Information System) that is used for a facility management, urban/cadastral management as well as in spatial analysis. In this paper, for an error analysis of X, Y coordinates data on digital map, test area was classified by topography, density, and slope. The coordinates on topographic map were assumed as true values and they were compared with the coordinates on digital map. A result of the numerical test show that a vector data of line type had more gross error than vector data of polygon type. And, SME(stanadrd mean error) of urban or intermountain area had small values compared to that of suburban area in topography analysis. The SME of dense and middle zone had small values compared to that of loose zone in density analysis. In another slope analysis. the SME of steep of gentle slope had small values compared to that of flatland.

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Effect of Estimation for Time of Concentration on the Design Flood (홍수도달시간 산정방법이 설계홍수량에 미치는 영향)

  • Kwon, Ki Dae;Lee, Jun Ho;Kang, Mi Jeong;Jee, Hong Kee
    • Journal of Wetlands Research
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    • v.16 no.1
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    • pp.125-137
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    • 2014
  • In this study, that the Kraven(II) empirical formula, the existing method to estimate the time of concentration in river basin, does not reflect the characteristics of relevant basin as it presents 3 stream velocities by section of slope was verified, and the time of concentration for the actual average stream velocity considering the characteristics of the basin was compared and analyzed by applying the continuous Kraven empirical formula, which was suggested recently by 'Design Flood Estimation Guide Line, 2012, Ministry of Land, Transport and Maritime Affairs' complementing the stream velocities for the easy slope and the steep slope, to the Donghwa-Cheon, the medium size river and the modality of changes in hydrograph was examined, For the Maeho-Cheon, Wuksu-Cheon and Geumpo-Cheon, the flood runoff simulation results according to the time of concentration application empirical formula considering the characteristics of relevant basin were compared and analyzed and following conclusions were able to obtain.

The Study of Alluvial Fans in Korea (한국(韓國) 선상지(扇狀地) 연구(硏究))

  • Park, No-Sik
    • Journal of the Speleological Society of Korea
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    • no.68
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    • pp.5-22
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    • 2005
  • Since earlier in 1947 the writer had been devoting part of his time to study alluvial fans in Korea based on his own interest in geomorphology. However, it was in 1958 when a new geography department was set up and the Research Center of National Lands was established in the university of Kyung Hee, the writer started scientific investigation for alluvial fans. The Following alluvial fans have been studied by the writer: those of Mt. Kwanak and Mt. Chungge in 1947; those of Pulkuksa in 1948; those of Suhnamsa, Suh Myun, Pusan in 1950; those of Shindonae, Mt. Kerrong, in summer of 1958; those of Hwaomsa, Kure and Yongsan Myun, Changhung, in winter of 1958. The article is the comparative study of the above mentioned alluvial fans including Suhkwangsa Fan, Chugaryng Rift Valley. Of course this is not the study covering all af alluvial fans in Korea. Within the limits of his surbey, the writer has com to a conclusion which may be helpful for the Korean alluvial fm study. 1. Korean alluvial fans are generally found in rift valleys or basins. 2. They are formed in places of below 220-meter contour line. 3. The slope from fna apex to river valley is 20-40 degree. The slope of fan surface is 5-20 degree, but most of them under 16 degree. A sudden change of slope is taken place or the fan apex and fan center. 4. Hills (100-200m) are developed on the surfaces of alluvial fans. 5. Most of rivers in alluvial fans are geyser rivers. 6. The depth of well : from ground surface to the well water surface is 4-8 m; water depth is 1-2m. 7. Land utilization; cultivated land 30%: non cultivatedland 70%. The area occupied by upland fields is twice of paddy field area. 8. Settlement : agglomerated settlement is developed on the top or the end of fan and surrounded by windbreakers. 9. Farming pattern at the top of fan fields are rectangular and parallel to flumes but at the center of fan, they are irregular and perpendicular to flumes.

The 90° hybrid Coupler having the same output power slope at two output ports (두 개의 출력단자에 동일한 출력 전력 기울기를 갖는 90° hybrid Coupler)

  • Park, Ung-hee
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2016.10a
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    • pp.85-88
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    • 2016
  • Two output ports of $90^{\circ}$ hybrid-coupler are generally the same output power with $90^{\circ}$ phase difference. But, Two output ports of $90^{\circ}$ hybrid-coupler must be the different output slope characteristic about frequency because of the different electrical length. In $90^{\circ}$ hybrid-coupler being the same power distribution, 3-dB power distribution at two output ports only exists near the center frequency. And, the output power difference between two output ports increases in accordance with the further away from the center frequency. This paper proposes $90^{\circ}$ hybrid-coupler being the similar output slope characteristic of two output ports in wideband to modify the ${\lambda}/4$ transmission line of $35-{\Omega}$ characteristic impedance between input port and output port near input port. The power difference between two output ports of the proposed circuit is below 0.2dB over 20% bandwidth of the center frequency in ADS(advanced Design System).

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A Study on the Cost of Capital of Islamic Enterprise (이슬람기업의 자본조달비용에 관한 연구)

  • Choi, Tae-Yeong
    • International Area Studies Review
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    • v.13 no.2
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    • pp.505-523
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    • 2009
  • We study the cost of capital of Islamic enterprise using the Capital Asset Pricing Model(CAPM). When there exists no risk-free interest rate, the security market line(SML) of Islamic enterprise shows an upward slope starting from the origin. The slope is bigger than that of SML with risk-free interest rate. This is because the cost of capital of Islamic enterprise is higher than that of western firms for the same level of systematic risk. When the effect of zakat is considered, the risk-free interest rate is replaced by minimum required rate of return. The SML of Islamic enterprise reveals an upward slope but it does not pass through the origin. This is because Islamic enterprise cannot invest on risk-free asset. In order to overcome the theoretic limits of CAPM, we propose to use multi-factor approach such as arbitrage pricing model instead of single-factor model for future study.

An experimental study on tailings deposition characteristics and variation of tailings dam saturation line

  • Wang, Guangjin;Tian, Sen;Hu, Bin;Kong, Xiangyun;Chen, Jie
    • Geomechanics and Engineering
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    • v.23 no.1
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    • pp.85-92
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    • 2020
  • This study adopted soil test and laboratory physical model experiments to simulate the tailings impoundment accumulation process according to the principle of similarity. Relying on the practical engineering, it analyzed the tailings deposition characteristics on dry beach surface during the damming process, as well as the variation rules of dam saturation line. Results suggested that, the tailings particles gradually became finer along the dry beach surface to inside the impoundment. The particle size suddenly changed at the junction between the deposited beach and the water surface, which displayed an obvious coarsening phenomenon. Besides, the deposited beach exhibited the vertical feature of coarse upward and fine downward on the whole. Additionally, in the physical model, the saturation line elevated with the increase in dam height, and its amplitude was relatively obvious within the range of 1.0-4.5 m away from the initial dam. Under flood condition, the saturation line height was higher than that under normal condition on the whole, with the maximum height difference of 4 cm. This study could provide an important theoretical basis for further studies on dam failure experiments and the evolution rules of leaked tailings flow.

Region Segmentation Algorithm of Object Using Self-Extraction of Reference Template (기준 템플릿의 자동 생성 기법을 이용한 물체 영역 분할 알고리즘)

  • Lee, Gyoon-Jung;Lee, Dong-Won;Joo, Jae-Heum;Bae, Jong-Gab;Nam, Ki-Gon
    • Journal of the Institute of Convergence Signal Processing
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    • v.12 no.1
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    • pp.7-12
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    • 2011
  • In this paper, we propose the technique detecting interest object region effectively in the images from periscope of submarine based on self-generated template. First, we extract the sea-sky line, and divide it into sky and sea area from background region based on the sea-sky line. In each divided background region, the blocks which can be represented in each background region are set as a reference template. After dividing an image into several same size of blocks, we apply multi template matching to the divided search blocks and histogram template to divide the image into object region and background region. Proposed algorithm is adapted to various images in which objects exist in the background of sea and sky. We verified that proposed algorithm performed properly without given informmed prby prior learning.ropso, regardless of the slope of sea-sky line and the locmed p of object based on sea-sky line, we verified that the objects region was segmented effectively from the input image.

A Study on the Prediction of Hard and Soft Tissue Changes after Setback Genioplasty (후진 이부성형술의 경조직과 연조직 측모 변화 예측에 관한 연구)

  • Yang, Jung-Eun;Kim, Il-Kyu;Cho, Hyun-Young;Ju, Sang-Hyun;Pyeon, Young-Hoon;Jung, Bum-Sang;Pae, Sang-Pill;Cho, Hyun-Woo
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.34 no.6
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    • pp.413-420
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    • 2012
  • Purpose: The purpose of this setback genioplasty study is to develop a prediction method for the calculated osteotomy angle using horizontal and vertical changes as well as to evaluate the proportion of hard and soft tissue changes. Methods: Twelve patients who had received setback genioplasty with other maxillofacial surgery were examined. Three lateral cephalograms were taken just before surgery, immediately after surgery, and 3 months later surgery. A reference line was established to the reference point of the inner most point of the lingual symphysis cortex, incisor tip, and 2nd molar cusp tip. Measuring was conducted from pogonion (Pg), menton (Me), labrale inferius (Li), Mentolabial fold, soft tissue pogonion (Pg'), and soft tissue menton (Me') to the reference lines. Results: In setback genioplasty, the skeletal Pg moved posteriorly 5.07 mm. The ratios of soft tissue to hard tissue movement were 36% posteriorly and 62% inferiorly at Pg', 67% posteriorly and 104% inferiorly at Me', and 34% anteriorly and 164% posteriorly at Li. In reduction & setback genioplasty, skeletal Pg moved posteriorly 4.63 mm and skeletal Me moved superiorly 3.63 mm. The ratios of soft tissue to hard tissue movement were 76% posteriorly and 18% superiorly at Pg', 68% posteriorly and 42% superiorly at Me', and 44% anteriorly, 124% posteriorly at Li. The calculated mean slope angle, based on ${\Delta}H/{\Delta}V$ ratio, was 61.25 and the measured mean slope angle was 60.17. Thus, the calculated and measured slope angles have a similarity. Conclusion: In setback genioplasty, soft tissue moves posteriorly and inferiorly. In particular, at the Me' and Pg', the inferior movement of the soft tissue is greater than the posterior movement. Also, the predictable results (measured slope angle) after operation can be achieved by the calculated slope angle. Thus, the relationship of soft and hard tissue changes must be considered as the results are predictable.