• Title/Summary/Keyword: Dominant Frequency Band

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Comparative Analysis of Structural Damage Potentials Observed in the 9.12 Gyeongju and 11.15 Pohang Earthquakes (9.12 경주지진 및 11.15 포항지진의 구조손상 포텐셜 비교연구)

  • Lee, Cheol-Ho;Kim, Sung-Yong;Park, Ji-Hun;Kim, Dong-Kwan;Kim, Tae-Jin;Park, Kyoung-Hoon
    • Journal of the Earthquake Engineering Society of Korea
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    • v.22 no.3
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    • pp.175-184
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    • 2018
  • In this paper, comparative analysis of the 9.12 Gyeongju and 11.15 Pohang earthquakes was conducted in order to provide probable explanations and reasons for the damage observed in the 11.15 Pohang earthquake from both earthquake and structural engineering perspectives. The damage potentials like Arias intensity, effective peak ground acceleration, etc observed in the 11.15 Pohang earthquake were generally weaker than those of the 9.12 Gyeongju earthquake. However, in contrast to the high-frequency dominant nature of the 9.12 Gyeongju earthquake records, the spectral power of PHA2 record observed in the soft soil site was highly concentrated around 2Hz. The base shear around 2 Hz frequency was as high as 40% building weight. This frequency band is very close to the fundamental frequency of the piloti-type buildings severely damaged in the northern part of Pohang. Unfortunately, in addition to inherent vertical irregularity, most of the damaged piloti-type buildings had plan irregularity as well and were non-seismic. All these contributed to the fatal damage. Inelastic dynamic analysis indicated that PHA2 record demands system ductility capacity of 3.5 for a structure with a fundamental period of 0.5 sec and yield base shear strength of 10% building weight. The system ductility level of 3.5 seems very difficult to be achievable in non-seismic brittle piloti-type buildings. The soil profile of the PHA2 site was inversely estimated based on deconvolution technique and trial-error procedure with utilizing available records measured at several rock sites during the 11.15 Pohang earthquake. The soil profile estimated was very typical of soil class D, implying significant soil amplification in the 11.15 Pohang earthquake. The 11.15 Pohang earthquake gave us the expensive lesson that near-collapse damage to irregular and brittle buildings is highly possible when soil is soft and epicenter is close, although the earthquake magnitude is just minor to moderate (M 5+).

A Study of Relationships between the Sea Surface Temperatures and Rainfall in Korea (해수면온도와 우리나라 강우량과의 상관성 분석)

  • Moon Young-Il;Kwon Hyun-Han;Kim Dong-Kwon
    • Journal of Korea Water Resources Association
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    • v.38 no.12 s.161
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    • pp.995-1008
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    • 2005
  • In this study, the principal components of rainfall in Korea are extracted by a method which consists of the independent component analysis combined with the wavelet transform, to examine the spatial correlation between seasonal rainfalls and global sea surface temperatures (SSTs). The 2-8 year band retains a strong wavelet power spectrum and the low frequency characteristics are shown by the wavelet analysis. The independent component analysis is performed by using the Scale Average Wavelet Power(SAWP) that is estimated by wavelet analysis. Interannual-interdecadal variation is the dominant variation, and an increasing trend is observed in the spring and summer seasons. The relationships between principal components of rainfall in the spring/summer seasons and SSTs existed in Indian and Pacific Oceans. Particularly, the SST zones, which represent a statistically significant correlation are located in the Philippine offshore and Australia offshore. Also, the three month leading SSTs in the same region we strongly correlated with the rainfall. Hence, these results propose a promising possibility of seasonal rainfall prediction by SST predictors.

The Characteristics of Practical Color Combination in Body Painting (바디페인팅에 활용된 배색 이미지 연구)

  • Lee, Haemiru;Kim, Sungnam
    • Journal of Fashion Business
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    • v.19 no.1
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    • pp.77-94
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    • 2015
  • Due to the inflammatory of body exposure it did not become popular to the Korean nation but the body painting as a body art is definitely required for it be become a new pure artwork. In this body painting color is the core factor for visual part and expression and coloring obtained from the color is very important in creating effective image. In Korea beauty industry the researches are limited to the study on coloring expression of general beauty makeup. Therefore, this research analyzes color images in recent body painting artworks by defining characteristics of colors and coloring applied by theme. For the research subjects, dominant and secondary colors were extracted from the artworks presented in preliminary and final rounds of year 2012 and 2013 World Body Painting Festival. For the selection of final coloring stimulation the most frequent coloring by theme was first chosen. Among them, 2 individual coloring bands were selected by theme among the high frequency colors. For the analysis of coloring image shown in body painting works total 8 coloring bands were created and they were compared and analyzed by indicating each divided coloring band on the coloring image scale by theme. In this research coloring image analysis was done after examining colors and coloring of artworks presented in World Body Painting Festival by theme. This research has its meaning that it provides information and guideline for coloring design work of body painting by analyzing coloring image used in color and coloring of body painting by theme.

The 40~50Day Intraseasonal Oscillation of the Geostationary Meteorological Satellite High Cloud Amount (GMS 상층운량의 40~50일 계절만 진동)

  • 하경자;서애숙
    • Journal of Environmental Science International
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    • v.5 no.5
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    • pp.619-633
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    • 1996
  • Intraseasonal variability of the tropical convection over the Indian/western Pacific is studied using the Geostationary Meteorological Satellite high cloud amount. This study is directed to find the tropical-extratropical interaction in the frequency range of intraseasonal and interannual variabilities of the summer monsoon occured over the domain of 90E-171W and 495-50N. Especially, in order to investigate the intraseasonal interaction of last Asia summer monsoon associated with the tropical convections in the high cloud amounts, the spatial and time structure of the intraseasonal oscillation for the movement-and the evolution of the large-scale connections are studied. To describe the spatial and the time evolution, the extended empirical orthogonal function analysis is applied. The first mode may be considered to a normal structure, indicating that the strong convection band over 90E-120E is extended to sastward but this mode was detected as the intraseasonal variability during summer monsoon. It is found that the dominant intraseasonal mode of the tropical convection consists of the spatial changes over a broad period range centered around 40~50days.

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Color Analyses on Digital Photos Using Machine Learning and KSCA - Focusing on Korean Natural Daytime/nighttime Scenery - (머신러닝과 KSCA를 활용한 디지털 사진의 색 분석 -한국 자연 풍경 낮과 밤 사진을 중심으로-)

  • Gwon, Huieun;KOO, Ja Joon
    • Trans-
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    • v.12
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    • pp.51-79
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    • 2022
  • This study investigates the methods for deriving colors which can serve as a reference to users such as designers and or contents creators who search for online images from the web portal sites using specific words for color planning and more. Two experiments were conducted in order to accomplish this. Digital scenery photos within the geographic scope of Korea were downloaded from web portal sites, and those photos were studied to find out what colors were used to describe daytime and nighttime. Machine learning was used as the study methodology to classify colors in daytime and nighttime, and KSCA was used to derive the color frequency of daytime and nighttime photos and to compare and analyze the two results. The results of classifying the colors of daytime and nighttime photos using machine learning show that, when classifying the colors by 51~100%, the area of daytime colors was approximately 2.45 times greater than that of nighttime colors. The colors of the daytime class were distributed by brightness with white as its center, while that of the nighttime class was distributed with black as its center. Colors that accounted for over 70% of the daytime class were 647, those over 70% of the nighttime class were 252, and the rest (31-69%) were 101. The number of colors in the middle area was low, while other colors were classified relatively clearly into day and night. The resulting color distributions in the daytime and nighttime classes were able to provide the borderline color values of the two classes that are classified by brightness. As a result of analyzing the frequency of digital photos using KSCA, colors around yellow were expressed in generally bright daytime photos, while colors around blue value were expressed in dark night photos. For frequency of daytime photos, colors on the upper 40% had low chroma, almost being achromatic. Also, colors that are close to white and black showed the highest frequency, indicating a large difference in brightness. Meanwhile, for colors with frequency from top 5 to 10, yellow green was expressed darkly, and navy blue was expressed brightly, partially composing a complex harmony. When examining the color band, various colors, brightness, and chroma including light blue, achromatic colors, and warm colors were shown, failing to compose a generally harmonious arrangement of colors. For the frequency of nighttime photos, colors in approximately the upper 50% are dark colors with a brightness value of 2 (Munsell signal). In comparison, the brightness of middle frequency (50-80%) is relatively higher (brightness values of 3-4), and the brightness difference of various colors was large in the lower 20%. Colors that are not cool colors could be found intermittently in the lower 8% of frequency. When examining the color band, there was a general harmonious arrangement of colors centered on navy blue. As the results of conducting the experiment using two methods in this study, machine learning could classify colors into two or more classes, and could evaluate how close an image was with certain colors to a certain class. This method cannot be used if an image cannot be classified into a certain class. The result of such color distribution would serve as a reference when determining how close a certain color is to one of the two classes when the color is used as a dominant color in the base or background color of a certain design. Also, when dividing the analyzed images into several classes, even colors that have not been used in the analyzed image can be determined to find out how close they are to a certain class according to the color distribution properties of each class. Nevertheless, the results cannot be used to find out whether a specific color was used in the class and by how much it was used. To investigate such an issue, frequency analysis was conducted using KSCA. The color frequency could be measured within the range of images used in the experiment. The resulting values of color distribution and frequency from this study would serve as references for color planning of digital design regarding natural scenery in the geographic scope of Korea. Also, the two experiments are meaningful attempts for searching the methods for deriving colors that can be a useful reference among numerous images for content creator users of the relevant field.

A Study on the Corelation between the Variation of Land Cover and Groundwater Recharge Using the Analysis of Landsat-8 OLI Data (Landsat-8 위성을 통한 토지피복 변화와 지하수 함양량 상관성 고찰)

  • Park, Seunghyuk;Jeong, Gyo-Cheol
    • The Journal of Engineering Geology
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    • v.30 no.3
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    • pp.347-378
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    • 2020
  • Based on monthly average groundwater recharge over a nearly 10 year period, results of fully integrated hydrologic modeling of SWAT-MODFLOW, land cover, land use, soil type and hydrologic response unit (HRU) was used to assess the dominant influencing factors of groundwater recharge spatial patterns in Jangseong district. As dominant factors, land cover was FRSE (forest-evergreen) and soil type was Samgag. Landsat-8 OLI imaging spectrometer data were acquired in the period 2003 to 2004 and seasonal bare soil lines (BSL) were estimated through NIR-RED plot. Extent of slope of BSL was from 1.092 to 1.343 and the intercept was from -0.004 to -0.015. To know correlation between spatial groundwater recharge and soil-vegetation indices (PVI, NDVI, NDTI, NDRI), this study employed frequency and regression analysis. On May, RED band increased up 3 to 4 times compared to other seasons and only one turning point appeared as recharge-index with upward parabola bell shape as results of existing research. Considering precipitation, if the various studies for relationship between groundwater recharge and soil-vegetation index just like NDVI are performed, it is possible to estimate groundwater recharge through analyzing remote sensing data.

The Design of Feature Selection Classifier based on Physiological Signal for Emotion Detection (감성판별을 위한 생체신호기반 특징선택 분류기 설계)

  • Lee, JeeEun;Yoo, Sun K.
    • Journal of the Institute of Electronics and Information Engineers
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    • v.50 no.11
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    • pp.206-216
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    • 2013
  • The emotion plays a critical role in human's daily life including learning, action, decision and communication. In this paper, emotion discrimination classifier is designed to reduce system complexity through reduced selection of dominant features from biosignals. The photoplethysmography(PPG), skin temperature, skin conductance, fontal and parietal electroencephalography(EEG) signals were measured during 4 types of movie watching associated with the induction of neutral, sad, fear joy emotions. The genetic algorithm with support vector machine(SVM) based fitness function was designed to determine dominant features among 24 parameters extracted from measured biosignals. It shows maximum classification accuracy of 96.4%, which is 17% higher than that of SVM alone. The minimum error features selected are the mean and NN50 of heart rate variability from PPG signal, the mean of PPG induced pulse transit time, the mean of skin resistance, and ${\delta}$ and ${\beta}$ frequency band powers of parietal EEG. The combination of parietal EEG, PPG, and skin resistance is recommendable in high accuracy instrumentation, while the combinational use of PPG and skin conductance(79% accuracy) is affordable in simplified instrumentation.

Asymmetric Activation in the Prefrontal Cortex and Heart Rate Variability by Sound-induced Affects (음향감성에 의한 전전두엽의 비대칭성과 심박동변이도)

  • Jang Eun-Hye;Lee Ji-Hye;Lee Sang-Tae;Kim Wuon-Shik
    • Science of Emotion and Sensibility
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    • v.8 no.1
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    • pp.47-54
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    • 2005
  • This study is aimed to inspect how the different sensitivities in Behavioral activation system(BAS) and behavioral inhibition system(BIS) modulate on the properties of physiological responses stimulated by positive or negative affective sound. We measured the electroencephalogram(EEG) and electrocardiogram (ECG) of 32 students, consisted of four groups depending on the BAS and BIS sensitivities, during listening to meditation music or noise. The EEG was recorded at Fpl and Fp2 sites and Power spectral density(PSD) of HRV was derived from the ECG, and the power of HRV was calculated for 3 major frequency ranges(low frequency[LF], medium frequency and high frequency[HF]). After listening to music or noise, subjects reported the affect induced by the sound. For EEG, the power in the alpha band at Fp2, especially in the alpha-2 band(9.0-11.0 Hz) increased during the subjects listening to music, while the power at Fpl increased during noise. During listening to meditation music, there is a tendency that the left-sided activation in prefrontal cortex(PFC) is positively correlated with the difference of BAS(Z)-BIS(Z). During listening to noise, there is a tendency that the right-sided activation in PFC is dominant in case any of the sensitivity of BAS or BIS is high. For HRV, we found that the index of MF/(LF+HF), during listening to music, was higher significantly in the individuals with a low BIS but high BAS than in the individuals with a low sensitivity both BIS and BAS individuals. With high BIS, regardless of the BAS sensitivity, the difference of this index values was not significant. From these results we suggest that the physiological responses of different individuals in BAS and BIS react differently under the same emotionally provocative challenge.

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An Analysis of 2007 Summer Women's Street Fashion in Dalian, China (2007년 여름 중국(中國) 대련(大連)시 여성 스트리트 패션 분석)

  • Bae, Soo-Jeong;Baek, Jeong-Hyun;Choi, Yoon-Kyu;Yoo, Wha-Jung
    • Journal of the Korean Society of Clothing and Textiles
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    • v.32 no.11
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    • pp.1692-1703
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    • 2008
  • On 2008, China comes to be an era of opening the market for 30 years, being both the 4th economically biggest country and 2nd ranked clothing export country in the world. China plays a huge consuming market for the world, along with the competition arena for the numerous world fashion brands while more than 100 kinds of Korean fashion ones being launched into the China. By applying the analysis and investigation of preferred street style. in local area to the development of fashion items and design, the synergistic effect of university and industrial corporation might also be expected. This study aims to provide the basic resources for the development of fashion design on behalf of the Korean fashion brands launched into China and moreover to anticipate the requirement on the part of Chinese consumers by way of understanding the preferred fashion styles, through analysis and investigation of the street fashion in Dalian, northeastern area of China. Conclusively, in terms of clothing style, 80.5% of casual style and 19.5% of formal style were notified. The jean casual, and easy casual being dominant in the former, feminine style in the later. In view of the high frequency of T-shirt, sleeveless on the top, full-length pants and 7/9 length pants on the bottom. The simple and cool style seems to be favored, making them easy through the hot summer. The upper clothes exposed in body part of back, chest and shoulder, were frequently shown. In light of colours. white, black, red were preferred on top, blue and black were preferred on bottom. To deal with accessories, the shoulder bag mostly preferred among bags, the sandal, slippers, snickers in sequential order among shoes, the hair pins and rubber band(tied or, held up style), in hair accessories. Other items of hat, belt, and sunglasses, which could give a point to the summer style, were identified low frequency.

Design of An Amplifier using DGS Block (DGS 방식 DC Block을 이용한 증폭기의 설계)

  • 이경희;정용채
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.12 no.3
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    • pp.432-438
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    • 2001
  • In this paper, after applying Defected Ground Structure(DGS) to DC block, changes of gap and length of λ/4 coupled line are investigated by EM simulation and fabrication. As a result, on condition of the same output with the case using typical DC block, the gap between λ/4 coupled line is widen from 0.1 mm to 0.46 mm by 0.36 mm and the length of λ/4 coupled line gets shorter from 17.7 mm to 13.2 mm by 4.5 mm. Also three type power amplifiers using blocking capacitor, typical DC block and DGS DC block are fabricated and investigated. At first, when S parameter characteristics of each amplifier are considered at frequency band of 3.2 +-0.O5 GHz, every amplifier has similar characteristics of gain and S parameter. Second when the output power of amplifiers is 25 dBm after putting CW signal of 3.2 GHz into three type amplifiers, the difference of dominant signal and 2nd harmonic signal using blocking capacitor, typical DC block and DGS DC block is each -44.83 dBc, -66.84 dBc and -64.33 dBc. Therefore harmonic characteristics of amplifiers using typical DC block and DGS DC block is almost same.

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