• Title/Summary/Keyword: EO Parameters

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Active Vibration Control of UAV EO/IR Sensor Mount Using Piezoelectric Actuator (압전작동기를 이용한 무인항공기 EO/IR 센서 마운트의 능동 진동 제어)

  • Park, Dong-Hyun;Choi, Seung-Bok
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.18 no.12
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    • pp.1278-1285
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    • 2008
  • This paper presents an inertia type of piezostack based active mount fur unmanned aero vehicle (UAV) camera system. After identifying the stiffness and damping properties of the rubber element and piezostack a mechanical model of the active mount system is established. The governing equation of mount is then derived and expressed in a state space form. Subsequently, a sliding mode controller which is robust to uncertain parameters is designed in order to reduce the vibration imposed according to the military specification associated with UAV camera mount system operation. Control performances such as acceleration and transmitted force are evaluated through both computer simulation and experimental implementation.

Ortho-rectification of a Digital Aerial Image using LiDAR-derived Elevation Model in Forested Area

  • Yoon, Jong-Suk
    • Korean Journal of Remote Sensing
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    • v.24 no.5
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    • pp.463-471
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    • 2008
  • The quality of orthoimages mainly depends on the elevation information and exterior orientation (EO) parameters. Since LiDAR data directly provides the elevation information over the earth's surface including buildings and trees, the concept of true orthorectification has been rapidly developed and implemented. If a LiDAR-driven digital surface model (DSM) is used for orthorectification, the displacements caused by trees and buildings are effectively removed when compared with the conventional orthoimages processed with a digital elevation model (DEM). This study utilized LiDAR data to generate orthorectified digital aerial images. Experimental orthoimages were produced using digital terrain model (DTM) and DSM. For the preparation of orthorectification, EO components, one of the inputs for orthorectification, were adjusted with the ground control points (GCPs) collected from the LiDAR point data, and the ground points were extracted by a filtering method used in a previous research. The orthoimage generated by DSM corresponded more closely to non-ground LiDAR points than the orthoimage produced by DTM.

Evaluation of valid time for analysis of complete blood cell in pig blood using the Hemavet 950FS (자동혈구분석기 Hemavet 950FS를 이용한 돼지 혈액 내 혈구분석의 유효시간 평가)

  • Kim, Ki-Hyun;Kim, Kwang-Sik;Kim, Doo-Wan;Sa, Soo-Jin;Kim, Young-Hwa
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.1
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    • pp.194-201
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    • 2017
  • This study was conducted to determine the valid time for accurate detection of complete blood cell count (CBC) in pig blood using an automatic blood corpuscle analyzer (Hemavet 950FS). Blood samples were collected from 34 pigs (Duroc) with a 60 kg (${\pm}3.5$) body weight. Ten specimens with CBC parameters in normal range and with no hemolysis were selected among 34 samples and used in this study. Regarding leukocytes parameters, white blood cell (WBC), neutrophil (NE), and lymphocyte (LY) counts showed a low daily variation (coefficient of variation, CV), whereas monocyte (MO), eosinophil (EO), and basophil (BA) CVs were significantly high (19.7, 56.9, and 53.3%, respectively). On the other hand, all parameters of erythrocytes and thrombocytes showed stable daily variation. All parameters of leukocytes and thrombocytes were significantly reduced as storage time passed (P<0.01 or 0.001), except for lymphocytes (P=0.535). However, no significant differences were observed in parameters of erythrocytes from blood up to 120 hours. From above results, we assert that Hemavet 950FS is useful in analyzing CBC, except for MO, EO, and BA. For accurate detection of leukocyte and thrombocyte parameters, analysis should be performed within 4 hours after blood collection when using Hemavet 950FS. On the other hand, parameters of erythrocytes could be stably detected for at least 120 hours after blood collection.

Magnetic Exchange Interactions in a 2D Grid-like Copper(II) Polymer with Bridging End-on Cyanato and Pyrazine Ligands: A DFT Study

  • Kang, Dae-Bok
    • Bulletin of the Korean Chemical Society
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    • v.31 no.6
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    • pp.1704-1710
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    • 2010
  • The structure of a 2D grid-like copper(II) complex [Cu$(NCO)_2$(pyz)](pyz=pyrazine) (1) consists of 1D chains of Cu-pyz units connected by double end-on (EO) cyanato bridges. Each Cu(II) ion has a distorted octahedral coordination, completed by the four EO cyanato and two pyrazine ligands. Magnetic interactions through EO cyanato and pyrazine bridges in 1 are discussed on the basis of DFT broken-symmetry calculations at the B3LYP level. For model dicopper(II) complexes I (bridged by cyanato) and II (bridged by pyrazine), electronic structure calculations reproduce very well the experimental couplings for the S = 1/2 ferromagnetic and antiferromagnetic exchange-coupled 2D system: the calculated exchange parameters J are +1.25 $cm^{-1}$ and -3.07 $cm^{-1}$ for I and II, respectively. The $\sigma$ orbital interactions between the Cu $x^2-y^2$ magnetic orbitals and the nitrogen lone-pair orbitals of pyrazine are analyzed from the viewpoint of through-bond interaction. The energy splitting of 0.106 eV between two SOMOs indicates that the superexchange interaction should be antiferromagnetic in II. On the other hand, there are no bridging orbitals that efficiently connect the two copper(II) magnetic orbitals in I because the HOMOs of the basal-apical NCO bridge do not play a role in the formation of overlap interaction pathway. The energy separation in the pair of SOMOs of I is calculated to be very small (0.054 eV). This result is consistent with the occurrence of weakly ferromagnetic properties in I.

DSM Generation and Accuracy Analysis from UAV Images on River-side Facilities (UAV 영상을 활용한 수변구조물의 DSM 생성 및 정확도 분석)

  • Rhee, Sooahm;Kim, Taejung;Kim, Jaein;Kim, Min Chul;Chang, Hwi Jeong
    • Korean Journal of Remote Sensing
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    • v.31 no.2
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    • pp.183-191
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    • 2015
  • If the damage analysis on river-side facilities such as dam, river bank structures and bridges caused by disasters such as typhoon, flood, etc. becomes available, it can be a great help for disaster recovery and decision-making. In this research, We tried to extract a Digital Surface Model (DSM) and analyze the accuracy from Unmanned Air Vehicle (UAV) images on river-side facilities. We tried to apply stereo image-based matching technique, then extracted match results were united with one mosaic DSM. The accuracy was verified compared with a DSM derived from LIDAR data. Overall accuracy was around 3m of absolute and root mean square error. As an analysis result, we confirmed that exterior orientation parameters exerted an influence to DSM accuracy. For more accurate DSM generation, accurate EO parameters are necessary and effective interpolation and post process technique needs to be developed. And the damage analysis simulation with DSM has to be performed in the future.

Abnormality of GCR intensities measured by ground NMs in solar minimum of solar cycles 23/24

  • Lee, Eo-Jin;Yi, Yu
    • Bulletin of the Korean Space Science Society
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    • 2009.10a
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    • pp.26.1-26.1
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    • 2009
  • Many solar, interplanetary and geomagnetic activity parameters have 11-year cycle on the average in sync with solar sunspot number. The galactic cosmic ray (GCR) intensity measured by ground Neutron Monitor (NM) is one of those parameters showing the unprecedented activity levels in the current solar minimum (2008-2009) of solar cycles 23/24. We defined abnormality as the ratio of deviation from long term mean over mean amplitude of solar cycle change. The abnormality distribution map was drawn using all the data of NM stations available online. The implications of those unprecedented levels of GCR intensities of different cutoff rigidities will be discussed.

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Experimental Characterization and Signal Integrity Verification of Interconnect Lines with Inter-layer Vias

  • Kim, Hye-Won;Kim, Dong-Chul;Eo, Yung-Seon
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.11 no.1
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    • pp.15-22
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    • 2011
  • Interconnect lines with inter-layer vias are experimentally characterized by using high-frequency S-parameter measurements. Test patterns are designed and fabricated using a package process. Then they are measured using Vector Network Analyzer (VNA) up to 25 GHz. Modeling a via as a circuit, its model parameters are determined. It is shown that the circuit model has excellent agreement with the measured S-parameters. The signal integrity of the lines with inter-layer vias is evaluated by using the developed circuit model. Thereby, it is shown that via may have a substantially deteriorative effect on the signal integrity of high-speed integrated circuits.

The Study of Biochemical Changes Induced by Fish Oil Diet in Rat ( II ) - Changes in Lipoprotein Lipase Activity and Mitochondrial Respiration and Structure - (어유(魚油)식이에 의한 흰쥐체내의 생화학적 변화연구(II) - Lipoprotein Lipase 활성과 미토콘드리아 호흡계의 변화 -)

  • Ha, Tae-Youl;Jung, Seung-Eun;Im, Jung-Gyo;Cho, Sung-Hee
    • Journal of Nutrition and Health
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    • v.17 no.4
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    • pp.297-304
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    • 1984
  • The effect of dietary fish oil ( mackerel oil : MO, eel oil : EO) on energy utilization in rats was studied with measurements of various tissue lipoprotein lipase( LPL ) and live and heart mitochondrial respiration. Fatty acid composition of mitrochondrial inner membrane matrix was also investigated. Dietary fat level was 10%( w/w) and reference groups were fed soybean oil (SO), repeseed oil ( RO) and beef tallow( BT ). Activity of LPL was about 60% higher in post-heparin plasma and 2 to 3 times higher in adipose tissue of BT group than fish oil or vegetable oil group. But there was no significant difference between fish oil and vegetable oil groups. Inclusion of EO above 2% (w/w) in dietary fat with fille oil of BT, markedly reduced both post -heparin plasma and adipose tissue LPL. Effects of MO and EO were not different in adipose tissue LPL, but EO was more effective than MO, in reducing post -heparin plasma LPL when mixed fat with varying amount of fish oil was used. Hepatic mitochondria isolated from fish oil-fed group showed the lowest rate of respiration but had P/O ratio comparable to SO and BT groups. On the other hand, cardiac mitochondria of fish oil group showed no difference in all the mitochondrial respiration parameters observed RO group had lowest P/O ratio both in hepatic and cardiac mitochondria. Fatty acid compositions of mitochondrial lipid differ between SO, RO, BT and MO groups, notably in the content of $C_{22:1}$ fatty acid.

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Analysis of the Effects of Three Line Scanner's Focal Length Bias (Three Line Scanner의 초점거리 오차의 영향에 관한 연구)

  • Kim, Changjae
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.32 no.1
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    • pp.1-8
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    • 2014
  • The positions, attitudes, and internal orientation parameters of three line scanners are critical factors in order to acquire the accurate location of objects on the ground. Based on the assumption that positions and attitudes of the sensors are derived either from direct geo-referencing which of using Global Positioning Systems (GPS) and Inertial Navigation Systems (INS), or from indirect geo-referencing which of using Ground Control Points (GCPs), this paper describes on biased effects of Internal Orientation Parameter (IOP) on the ground. The research concentrated on geometrical explanations of effects from different focal length biases on the ground. The Synthetic data was collected by reasonable flight trajectories and attitudes of three line scanners. The result of experiments demonstrated that the focal length bias in case of indirect geo-referencing does not have critical influences on the quality of reconstructed ground space. Also, the relationships between IO parameters and EO parameters were found by the correlation analysis. In fact, the focal length bias in case of the direct geo-referencing caused significant errors on coordinates of reconstructed objects. The RMSE values along the vertical direction and the amount of focal length bias turned out to be almost perfect linear relationship.

Detrended fluctuation analysis of magnetic parameters of solar active regions

  • Lee, Eo-Jin;Moon, Yong-Jae
    • The Bulletin of The Korean Astronomical Society
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    • v.41 no.1
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    • pp.81.2-81.2
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    • 2016
  • Many signals in the nature have power-law behaviors, namely they are "scale-free". The method of detrended fluctuation analysis (DFA), as one of the popular methods (e.g., Rescaled range analysis and Spectral analysis) for determining scale-free nature of time series, has a very important advantage that the DFA can be applied to both stationary and non-stationary signals. The analysis of time series using the DFA has been broadly used in physiology, finance, hydrology, meteorology, geology, and so on. We performed the DFA of 16 Spaceweather HMI Active Region Patch (SHARP) parameters for 38 HMI Active Region Patches (HARPs) obtained by Solar Dynamics Observatory (SDO) from May 2010 to June 2014. The main results from this study are as follows. (1) The most of the time series data are non-stationary. (2) The DFA scaling exponents of "mean vertical current density" for 38 HARPs have a negative correlation coefficient (-0.41) with flare index. (3) The DFA scaling exponents of parameters such as "Sum of the absolute value of net currents per polarity", "Absolute value of the net current helicity", and "Mean photospheric excess magnetic energy density" for the most active HARPs having more than 10 major flares, have positive correlation coefficients (0.64, 0.59, and 0.53, respectively) with the ratio of "the number of CMEs associated with major flares" to "the number of major flares". Physical interpretations on our results will be discussed.

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