• Title/Summary/Keyword: gamma wave

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Wave Overtopping Formula for Vertical Structure Including Effects of Wave Period : Non-breaking Conditions (주기영향을 고려한 직립식 구조물의 월파량 산정 : 비쇄파조건)

  • Kim, Young-Taek;Lee, Jong-In
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.24 no.3
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    • pp.228-234
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    • 2012
  • Two-dimensional hydraulic experiments for wave overtopping under non-breaking wave condition are conducted. The wave overtopping formula for vertical structure is suggested and the results are compared with EurOtop (2007). The relative water depth coefficient (${\gamma}_{kh}$) shows that almost the same coefficient is obtained for certain range (kh > 1.55) regardless of relative water depth, that is, although the relative water depth becomes larger, the relative water depth coefficient is almost same. When the wave steepness becomes larger the wave steepness coefficient decreases. The overtopping formula are expressed by relative freeboard(R) and non-dimensional wave overtopping rate(Q) and this formula has the form of exponential function. In this formula, the effects of wave period on wave overtopping are quantitatively investigated and suggested through the relative water depth coefficient(${\gamma}_{kh}$) and wave steepness coefficient(${\gamma}_s$).

Application of Artificial Neural Networks to Search for Gravitational-Wave Signals Associated with Short Gamma-Ray Bursts

  • Oh, Sang Hoon;Kim, Kyungmin;Harry, Ian W.;Hodge, Kari A.;Kim, Young-Min;Lee, Chang-Hwan;Lee, Hyun Kyu;Oh, John J.;Son, Edwin J.
    • The Bulletin of The Korean Astronomical Society
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    • v.39 no.2
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    • pp.107.1-107.1
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    • 2014
  • We apply a machine learning algorithm, artificial neural network, to the search for gravitational-wave signals associated with short gamma-ray bursts. The multi-dimensional samples consisting of data corresponding to the statistical and physical quantities from the coherent search pipeline are fed into the artificial neural network to distinguish simulated gravitational-wave signals from background noise artifacts. Our result shows that the data classification efficiency at a fixed false alarm probability is improved by the artificial neural network in comparison to the conventional detection statistic. Therefore, this algorithm increases the distance at which a gravitational-wave signal could be observed in coincidence with a gamma-ray burst. We also evaluate the gravitational-wave data within a few seconds of the selected short gamma-ray bursts' event times using the trained networks and obtain the false alarm probability. We suggest that artificial neural network can be a complementary method to the conventional detection statistic for identifying gravitational-wave signals related to the short gamma-ray bursts.

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Peak mooring forces in the horizontal interlaced multi-layered moored floating pipe breakwater

  • Mane, Vishwanath;Rajappa, Sacchi;Rao, Subba;Vittal, Hegde A.
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.3 no.2
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    • pp.150-158
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    • 2011
  • Present study aims to investigate the influence of relative breakwater width W/L (W=width of breakwater, L=wavelength), wave steepness $H_i/gT^2$ (Hi=incident wave height, T=wave period) and relative wave height d/W (d=water depth) on forces in the moorings of horizontal interlaced multi-layered moored floating pipe breakwater (HIMMFPB) model. Studies were conducted on scaled down physical models having three layers of Poly Vinyl Chloride (PVC) pipes, wave steepness $H_i/gT^2$ varying from 0.063 to 0.849, relative width W/L varying from 0.4 to 2.65 and relative spacing S/D=2 (S=horizontal centre-to-centre spacing of pipes, D=diameter of pipes). Peak mooring forces were also measured and data collected is analyzed by plotting non-dimensional graphs depicting variation of $f_s/{\gamma}W^2$ ($f_s$=Sea side Mooring force, ${\gamma}$=specific weight of water) & $f_l/{\gamma}W^2$ ($f_l$=Lee side Mooring force) with $H_i/gT^2$ for d/W varying from 0.082 to 0.276 and also variation of $f_s/{\gamma}W^2$ and $f_l/{\gamma}W^2$ with W/L for $H_i$/d varying from 0.06 to 0.400.

Evaluation of Wave Characteristics and JONSWAP Spectrum Model in the Northeastern Jeju Island on Fall and Winter (제주도 북동부 연안에서 추동계 파랑특성과 JONSWAP 스펙트럼의 적용성 평가)

  • Kang, Dong-Hyub;Lee, Byung-Gul
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.17 no.2
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    • pp.63-69
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    • 2014
  • Analysis frequency spectrum through observed wave data in northeastern shore, jeju island, during winter and fall, and review wave characteristics. In order to compute maximum wave height, we calculate the ratio of significant wave height to maximum wave height using the linear regression equation. In addition, for calculating JONSWAP spectrum, we assumed ${\gamma}$ value using significant wave height and peak frequency in the observation area. Consequently, the highest frequency is below 1 m in the case of significant wave height and during the first observation, the mean of height was estimated at 0.523 m and during the scend observation, it was 0.423 m. Furthermore, in peak frequency, the highest frequency was 0.12 Hz~0.15 Hz (period is nearly 6.67s~8.33s), the results of ${\gamma}$ from using significant wave height and peak frequency is 2.72 and the significant wave height calculated by straight linear regression equation was $1.635H_s$.

Effect of Irradiation on Growth, Bulblet Formation, and Germination of Pollen and Seed of Several Lily Cultivars (나리 생장, 자구 발달 및 화분과 종자발아에 미치는 방사선의 영향)

  • Park, In Sook;Suh, Dong Hee;Hwang, Yoon Jung;Chung, Jae-Dong;Kang, Si-Yong;Lim, Ki-Byung
    • FLOWER RESEARCH JOURNAL
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    • v.16 no.3
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    • pp.211-217
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    • 2008
  • To build up data for mutation breeding of lily, sensitivity to irradiation of bulb, seed and pollen was investigated. The bulbs of seven cultivars including 'New Wave' were very sensitive to gamma rays. Non-irradiated bulbs produced plants with bloom as normal. However, irradiated bulbs showed retarded growth and did not flower. Bulbs of 'New Wave' and 'Tiny Dino' irradiated with 125Gy gamma rays survived, but their growth rate dropped considerably. Part or whole leaves of the other cultivars except 'New Wave' and 'Tiny Dino' withered. Moisture content of individual scale was 72~78% depending on cultivar. Bulblet formation from untreated scales was 100%. Among all irradiated scales only 'Siberia' scales showed 8.5% bulblet formation when irradiated with 50Gy gamma rays. Pollen germination as affected by gamma ray irradiation had no consistent tendency. When dosage of $F_1$ 'Augusta' seeds reached 300Gy, their survival ratio was drastically decreased. Bulblet formation in vitro was observed only in non-irradiated seeds. Lethal dose ($LD_{50}$) of seed was less than 100Gy. Height and width of $F_1$ 'Augusta' bulblets in vitro irradiated with gamma rays decreased as dosage increased regardless of the culture method. The percentage shoot formation was 100% in non-irradiated bulblets and 15~60% in irradiated ones.

Comparative Study of surface passivation for Metamorphic HEMT using low-k Benzocyclobutene(BCB) (Metamorphic HEMT에서 low-k Benzocyclobutene(BCB)를 이용한 표면 passivation 비교 연구)

  • Baek, Yong-Hyun;Oh, Jung-Hun;Han, Min;Choi, Seok-Gyu;Lee, Bok-Hyung;Lee, Seong-Dae;Rhee, Jin-Koo
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.44 no.4
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    • pp.80-85
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    • 2007
  • The passivation is one of the important technologies for protection of the devies from damage. In this paper, we fabricated $0.1{\mu}m\;{\Gamma}$--gate InAIAs/InGaAs metamorphic high electron mobility transistors (MHEMTs) on a GaAs substrate. And then the wafer with MHEMTs was divided into two pieces; one for passivation and another for without passivation experiments. The passivations were done by using both low-k BCB and Si3N4 thin films. DC and RF performances were measured and the results are compared. The MHEMTs with BCB passivation show lower degradation than ones with Si3N4 passivation.

Analysis of Radiation Characteristics of Microstrip Patch Antennas Integrated with Mushroom-like EBG Structures (Mushroom 형태의 EBG 구조를 집적한 마이크로스트립 패치안테나의 방사 특성 해석)

  • Kwak, Eun-Hyuk;Kim, Tae-Young;Kim, Boo-Gyoun
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.46 no.8
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    • pp.67-78
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    • 2009
  • Radiation characteristics of microstrip patch antennas integrated with mushroom-like EBG structures in all directions and length direction on a substrate with the relative dielectric constant of 10 are systematically analyzed. As the substrate thickness increases, the effect of the surface wave on the input impedance and radiation pattern of a patch antenna increases. The effect of EBG structures on the input impedance of a patch antenna is negligible when the distances between EBG structures and the center of a patch antenna are 0.4 ${\gamma}_0$, 0.2 ${\gamma}_0$ and 0.1 ${\gamma}_0$ for the substrate thickness of 3.2 mm, 1.6 mm and 0.8 mm, respectively. The forward radiation is improved due to the suppression of surface wave when the periods of EBG structures integrated are larger than 2, 2, 3 periods for the substrate thickness of 3.2 mm, 1.6 mm and 0.8 mm, respectively. The effects of EBG structures on the radiation characteristics of a patch antenna integrated with EBG structures in all directions and length direction are similar.

A Study on Effects of incense smokes of 'Cheung-Woon' on Concentration (한방(韓方) 훈법(熏法)을 이용한 '청운(淸雲)'의 집중력 효과에 관한 연구)

  • Uhm, Ji-Tae;Kim, Byoung-Soo;Kim, Kyoung-Shin
    • Journal of Oriental Neuropsychiatry
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    • v.23 no.2
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    • pp.33-48
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    • 2012
  • Objectives : This study aimed to assess the effects of incense smokes of 'Cheung-Woon' on the concentration and EEG in healthy individuals. Methods : A total of 48 healthy volunteers participated in this study. The volunteers were examined with K-MAS, CBT(Corsi block tapping task), and EEG before and after smelling the incense smokes of 'Cheung-Woon'. K-MAS measured the recalled words, and CBT measured the recalled positions and orders of the color boxes. EEG measured the relative power of ${\theta}$ wave, ${\alpha}$ wave, SMR wave, mid-${\beta}$ wave, high-${\beta}$ wave, ${\gamma}$ wave and T(concentraion index T = (SMR wave + mid-${\beta}$ wave) / ${\theta}$ wave). 'Cheung-Woon' consists of 7 herbal powder, known as a useful effect on the concentration and memory. Results : After smelling 'Cheung-Woon', K-MAS were increased significantly(p<0.05). In relative power of ${\theta}$ wave, F4, T3, and P4 were decreased significantly(p<0.05) and P3 was also decreased significantly(p<0.01). In the relative power of ${\alpha}$ wave, SMR wave, and mid-${\beta}$ wave, the values were not significant. In the relative power of high-${\beta}$ wave, Fp1, and P4 were increased significantly(p<0.05). In relative power of ${\gamma}$ wave, T3 were increased significantly (p<0.05). In T value, F4, T3, T4, and P4 were increased significantly(p<0.05) and P3 were also increased significantly(p<0.01). Conclusions : This results show that smelling incense smokes of 'Cheung-Woon' is an effective way of increasing concentration and memory.

CAVITY OF CREATION FOR COLD FUSION AND GENERATION OF HEAT

  • Oh, Hung-Kuk
    • Proceedings of the Korea Society for Energy Engineering kosee Conference
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    • 1996.10b
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    • pp.3-12
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    • 1996
  • Cold fusion technologies now are being developed very successfully. The $\pi$-far infrared rays are generated from three dimensional crystallizing $\pi$-bondings of oxygen atoms in water molecules. The growing cavity in water molecules make near resonance state and a vortex of infrared rays and attracts $\pi$-far infrared rays in the water. The cavity surrounded by a lot of $\pi$-far infrared rays has a very strong gravitational field. The $\pi$-far infrared rays are contracted into $\pi$-far infrared rays of half wave length and of one wave length. The $\pi$-far infrared rays of half wave length generate heat while $\pi$-far infrared rays of one wave length are contracted into $\pi$-gamma rays of one wave length. The contracted $\pi$-gamma rays of one wave length make nucleons and mesons, which is the creation and transmutation of matter by covalent bondings and three-dimensional crystallizing $\pi$-bondings into implosion bonding. Patterson power cell generates a very strong gravitational cavity because the electrolysized oxygen atoms make $\pi$-far infrared rays than in plain water.

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Long-term Wave Monitoring and Analysis Off the Coast of Sokcho (속초 연안의 장기 파랑관측 및 분석)

  • Jeong, Weon Mu;Ryu, Kyung-Ho;Cho, Hongyeon
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.27 no.4
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    • pp.274-279
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    • 2015
  • Wave data acquired over eleven years near Sokcho Harbor located in the central area of the east coast were analyzed using spectral method and wave-by-wave analysis method and its major wave characteristics were examined. Significant wave heights were found to be high in winter and low in summer, and peak periods were also found to be long in winter and short in summer. The maximum significant wave height observed was 8.95 m caused by the East Sea twister. The distributional pattern of the significant wave heights and peak periods were both fitted better by Kernel distribution function than by Generalized Gamma distribution function and Generalized Extreme Value distribution function. The wave data were compiled to subdivide the wave height into intervals for each month, and the cumulative occurrence rates of wave heights were calculated to be utilized for the design and construction works in nearby construction works.