• Title/Summary/Keyword: Spectrum effect

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The Earthquake Response Characteristics and Seismic Safety Evaluation of Steel Cable Stayed Bridges (강사장교의 지진응답특성 및 내진 안전성 평가)

  • Han, Sung Ho;Shin, Jae Chul;Choi, Jin Woo
    • Journal of Korean Society of Steel Construction
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    • v.19 no.5
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    • pp.435-454
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    • 2007
  • In this study, we demonstrated the characteristics of the near-fault ground motion thatwas not considered in the domestic seismic design code and how the effect of the near-fault ground motion affects the response of cable-stayed bridges. Afterselecting the actual measurement records of the typical near- and far-fault ground motion, the characteristics of ground motion is analyzed using the elastic and inelastic response spectrum. Analyzing the response regarding the earthquake's characteristics on cable-stayed bridges by the typical three-type cable-stayed bridges and the actual cable-stayed bridge, the characteristics of responses about main members are compared and analyzed. Moreover,reliability analysis is accomplished using the results of the seismic response analysis, and the seismic safety of the cable-stayed bridges is evaluated quantitatively as a reliability index and probability of failure. According to the results of the response spectrum, the earthquake response analysis and the reliability analysis, because the effect of the near fault ground motion against the response of cable-stayed bridges is different from the effect of the existing far-fault ground motion, it should be considered as an important factor when designing cable-stayed bridges.

Physiological Activity of Aconitum pseudolaeve var erectum Nakai and Its Effect on Perfume on an Electroencephalogram (EEG) (진범(Aconitum pseudolaeve var erectum Nakai)의 생리활성과 진범 향이 뇌파에 미치는 영향)

  • Lee, Jin-Young;Choi, Yeon-Hee;Lee, Sae-Mi;Lee, Soo-Yeon;Jun, Hye-Ji
    • Journal of Life Science
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    • v.22 no.9
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    • pp.1214-1223
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    • 2012
  • This study analyzed the in vitro physiological activity of Aconitum pseudolaeve var erectum Nakai (AP) and its effect on perfume on an electroencephalogram (EEG). The results indicated that the absolute alpha power spectrum (AA) and the absolute theta power spectrum (AT) decreased significantly during more than before the inhalation of the AP perfume and its reconstruction perfume. Although there were a little different pattern in the induced part of the wave generated by the inhalation of the AP perfume and its reconstruction perfume, alpha- and theta- were shown equally. In addition, there was the same pattern in which the rate of increase reduced. The results suggest that the perfume of the AP and its reconstruction perfume have a stimulating effect on the brain. In terms of the physiological activity of AP, the activity of AP ethanol extract was significantly higher than that of water extract in DPPH, collagenase, and nitric oxide, except for an astringent effect. The AP ethanol extract was about 80% at 500 ppm in collagenase inhibition activity. In addition, the AP water and ethanol extracts were 50% at 100 ppm in the NO inhibition activity. Based on these results, we conclude that this natural substance could be used in cosmetics and in the development of perfumes.

Frequency Compatibility of FH Spread spectrum Communications in TV Channels (FH대역확산통신과 TV채널의 주파수 양립성에 관한 연구)

  • 박창일;조형래;이명수;강창언
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.14 no.1
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    • pp.84-92
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    • 1989
  • The purpose of this paper is to demonstrate the effect of a FH spread spectrum communication interference in TV channels and frequency compatibility in 30-88 MHz frequency band. To calculate this interferece, the strength of electric field of TV signals is derived as a function of distance between TV transmitter and receiver. An interference model is established based upon thefield strength by using the relation between the transmitted power of FH spread spectrum communications and the distance between the TV image signals, which makes TV screen a cceptble, Simultaneous transmission of FH sprea spectrum signals and TV signals is shown to be feasible, as far as the interference level is lower than the TV image signal level by 23.5dBm. As a result of frequency analysis and experiment, the FH spread spectrum communication can be used together with TV channels.

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Atomic Coherence Spectroscopy in the Paraffin Coated Rb Atom Vapor Cell (파라핀 코팅된 Rb원자 증기 셀에서 원자결맞음 분광)

  • Lee, Hyun-Joon;Yu, Ye-Jin;Bae, In-Ho;Moon, Han-Seb
    • Korean Journal of Optics and Photonics
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    • v.19 no.4
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    • pp.334-340
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    • 2008
  • We investigated the electromagnetically induced transparency (EIT) and the Hanle spectrum in a paraffin coated Rb vapor cell. The EIT spectrum was observed in the $F_g=2$, $3{\rightarrow}F_e=3$ transition of the $^{85}Rb$ $D_1$-line by using two independent external cavity diode lasers, and the Hanle spectrum was observed by using one external cavity diode laser in the $\Lambda$-type scheme between the Zeeman sublevels of the $F_g=2{\rightarrow}F_e=1$ transition of the $^{87}Rb$ $D_1$-line. In the Hanle spectrum, we could observe the dual-structured spectrum in the paraffin coated vapor cell. We investigated the dual-structured lineshape by applying an external magnetic field, and varying the direction of the magnetic field. The narrow linewidth of dual-structured EIT was measured to be approximately 200 Hz.

Autism Spectrum Disorder Detection in Children using the Efficacy of Machine Learning Approaches

  • Tariq Rafiq;Zafar Iqbal;Tahreem Saeed;Yawar Abbas Abid;Muneeb Tariq;Urooj Majeed;Akasha
    • International Journal of Computer Science & Network Security
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    • v.23 no.4
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    • pp.179-186
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    • 2023
  • For the future prosperity of any society, the sound growth of children is essential. Autism Spectrum Disorder (ASD) is a neurobehavioral disorder which has an impact on social interaction of autistic child and has an undesirable effect on his learning, speaking, and responding skills. These children have over or under sensitivity issues of touching, smelling, and hearing. Its symptoms usually appear in the child of 4- to 11-year-old but parents did not pay attention to it and could not detect it at early stages. The process to diagnose in recent time is clinical sessions that are very time consuming and expensive. To complement the conventional method, machine learning techniques are being used. In this way, it improves the required time and precision for diagnosis. We have applied TFLite model on image based dataset to predict the autism based on facial features of child. Afterwards, various machine learning techniques were trained that includes Logistic Regression, KNN, Gaussian Naïve Bayes, Random Forest and Multi-Layer Perceptron using Autism Spectrum Quotient (AQ) dataset to improve the accuracy of the ASD detection. On image based dataset, TFLite model shows 80% accuracy and based on AQ dataset, we have achieved 100% accuracy from Logistic Regression and MLP models.

Analysis of Characteristics of Vertical Response Spectrum of Ground Motions from Domestic Earthquakes (국내 관측자료를 이용한 수직 응답스펙트럼 특성 분석)

  • Kim, Jun-Kyoung;Hong, Seung-Min;Park, Ki-Jong
    • Geophysics and Geophysical Exploration
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    • v.13 no.3
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    • pp.227-234
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    • 2010
  • The vertical response spectra using the observed ground motions from the recent more than 30 macro earthquakes were analysed and then were compared both to the seismic design response spectra (Reg Guide 1.60), applied to the domestic nuclear power plants, and to the Korean Standard Design Response Spectrum for general structures and buildings (1997). 176 vertical ground motions, without considering soil types, were used for normalization with respect to the peak acceleration value of each ground motion. The results showed that response spectrum had strong dependency on epicentral distance. The results also showed that the vertical response spectra revealed much higher values for frequency bands above 5~7 Hz than Reg. Guide (1.60). The results were also compared to the Korean Standard Response Spectrum for the 3 different soil types and showed that the vertical response spectra revealed much higher values for the frequency bands below 0.2 second (5 Hz) than the Korean Standard Response Spectrum (SD soil condition). These frequency-dependent spectral values could be related to the characteristics of the domestic crustal attenuation and the effect of each site amplification. However, through the qualitative improvements and quantitative enhancement of the observed ground motions, the conservation of vertical seismic design response spectrum should be considered more significantly for the frequency bands above 5 Hz.

Analysis of Characteristics of Horizontal Response Spectrum of Ground Motions from 19 Earthquakes (국내 관측자료를 이용한 수평 응답스펙트럼 특성 분석)

  • Kim, Jun-Kyoung
    • Tunnel and Underground Space
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    • v.20 no.6
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    • pp.399-407
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    • 2010
  • The horizontal response spectra using the observed ground motions from the recent more than 19 macro earthquakes were analysed and then were compared to both the seismic design response spectra (Reg Guide 1.60), applied to the domestic nuclear power plants, and the Korean Standard Design Response Spectrum for general structures and buildings (1997). 130 horizontal ground motions, without considering soil types, were used for normalization with respect to the peak acceleration value of each ground motion. The results showed that response spectrum have strong dependency on epicentral distance. The results also showed that the horizontal response spectra revealed much higher values for frequency bands above 5 Hz than Reg. Guide (1.60). The results were also compared to the Korean Standard Response Spectrum for the 3 different soil types and showed that the vertical response spectra revealed much higher values for the frequency bands below 0.3 second than the Korean Standard Response Spectrum (SD soil condition). These spectral values dependent on frequency could be related to characteristics of the domestic crustal attenuation and the effect of each site amplification. However, through the qualitative improvements and quantitative enhancement of the observed ground motions, the conservation of horizontal seismic design response spectrum should be considered more significantly for the frequency bands above 5 Hz.

Image Quality Improvement through Energy Spectrum Change for X-ray (엑스선 에너지스펙트럼 변경을 통한 영상 화질 향상에 관한 연구)

  • Kim, Gu;Kim, Neung Gyun;Lee, Seung-Jae
    • Journal of the Korean Society of Radiology
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    • v.15 no.1
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    • pp.71-78
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    • 2021
  • When continuous X-ray are used when acquiring and X-ray image, even the same material may not be accurately represented in the image according to the thickness due to various X-ray energies. To solve this problem, the X-ray energy spectrum was changed to improve the image quality. Using SPEKTR v3.0, an X-ray energy spectrum with an additional filter added and a general X-ray energy spectrum using only a unique filter were obtained. Simulation was performed using the obtained X-ray energy spectrum as a radiation source for Geant4 Application for Tomographic Emission (GATE). Using GATE data, an X-ray image with an additional filter and an image reconstructed from and X-ray image without an additional filter were compared and analyzed through a mono energy image of 74 keV. In the case of using the X-ray energy spectrum without using an additional filter, the amount of X-rays transmitted according to the thickness of the same material is different from the amount that decreases according to the thickness of the material. Similar results were obtained as the amount decreased with the material thickness. In other words, a similar result was obtained when the reduced dose was used with a mono energy. When an X-ray image is obtained by changing an X-ray energy spectrum using an additional filter, a more accurate result of transmission of X-rays may be obtained. In radiological examination, it was confirmed that the appropriate use of the additional filter has a great effect on improving the image quality.

Effect of Bouc-Wen Model and Earthquake Characteristics for Responses of Seismically Isolated Nuclear Power Plant by Lead-Rubber Bearing (납-고무 받침에 의해 면진된 원전구조물의 응답에 대한 Bouc-Wen 모델 및 지진특성의 영향)

  • Song, Jong-Keol;Son, Min-Kyun
    • Journal of the Earthquake Engineering Society of Korea
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    • v.21 no.2
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    • pp.95-103
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    • 2017
  • In order to modeling seismic isolation system such as lead-rubber bearing (LRB), bilinear model is widely used by many researchers. In general, an actual force-displacement relationship for LRB has a smooth hysteretic shape. So, Bouc-Wen model with smooth hysteretic shape represents more accurately actual hysteretic shape than bilinear model. In this study, seismic responses for seismically isolated nuclear power plant (NPP) with LRB modelled by Bouc-Wen and bilinear models are compared with those of NPP without seismic isolation system. To evaluate effect of earthquake characteristics for seismic responses of NPP isolated by LRB, 5 different site class earthquakes distinguished by Geomatrix 3rd Letter Site Classification and artificially generated earthquakes corresponding to standard design spectrum by Reg. Guide 1.60 are used as input earthquakes. From the seismic response results of seismically isolated NPP, it can be observed that maximum displacements of seismic isolation modelled by Bouc-Wen model are larger than those by bilinear model. Seismic responses of NPP with LRB is significantly reduced than those without LRB. This reduction effect for seismic responses of NPP subjected to Site A (rock) earthquakes is larger than that to Site E (soft soil) earthquakes.

Isolation and Molecular Identification of Bacteriocin-producing Enterococci with Broad Antibacterial Activity from Traditional Dairy Products in Kerman Province of Iran

  • M, Khodaei;Sh, Soltani Nezhad
    • Food Science of Animal Resources
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    • v.38 no.1
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    • pp.172-179
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    • 2018
  • One of the critical limitations to use of bacteriocins produced by lactic acid bacteria as a substitute for chemical antibiotics is the narrow spectrum of their antibacterial activity. The aim of present study was isolation and molecular identification of bacteriocin-producing enterococci with broad antibacterial spectrum. Bacteriocin-producing bacteria were isolated from native dairies in Kerman. Bacteriocins were purified by ammonium sulfate method and the effects of them were investigated on different strains of bacteria. Also, the effects of pH and heat on produced bacteriocins were investigated. High level bacteriocin-producing isolates were identified based on molecular tests. A total of 15 strains of bacteriocin-producing Enterococcus were isolated initially. Enterococcus faecium C-2 and Y-1 strains produced bacteriocins with the highest antibacterial effect. The bacteriocins were stable in pH ranges from 2 to 12 and their antibacterial activity was maintained after autoclave treatment. The maximum bactericidal effect was observed against Listeria monocytogenes and Pseudomonas aeruginosa. In conclusion, use of these bacteriocins as a substitute for chemical antibiotics is recommended.