• Title/Summary/Keyword: Fractal

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Fundamental Studies on Human Sciences by Facial Form Analysis - Based on Unit Fluid Model of Essence, Qi energy, Emotion, Blood - (안면형상연구의 인간과학적 기초 연구 - 정기신혈(精氣神血)의 유체역학적(流體力學的) 해석을 중심으로 -)

  • Kim, Jong-Won;Lee, In-Seon;Kim, Kyu-Kon;Lee, Yong-Tae;Kim, Kyung-Chul;Eom, Hyun-Sup;Chi, Gyoo-Yong
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.22 no.5
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    • pp.1057-1061
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    • 2008
  • For the purpose of investigating the reasonable logics contained in physiognomy of east and old western medicine. hypothetical researches based on hydromechanics theory were performed concerning facial types of form and pathologic features, especially 4 types of Dr. Jisan-Essence, Qi energy. Emotional Activity and Blood(EQAB). In order to infer the functional relation between facial type forming and EQAB factors, EQAB were supposed as fluid grounded on their continual flowing or periodical change and pressure effect from its congestion. and a premise that there's a linear corresponding relationship between the appearance of organ and its physical conditions of its inner vessels is formed too. Through this work, the unit fluid model(UFM) of Essence can be assumed as circle shape formed by the high viscosity and surface tension, the UFM model of Qi energy as quadrangular shape by the scattering features to outer four directions, and the UFM of emotional activity as inverted triangular shape by the flippant and uprising features, and the UFM of blood as ellipsoid triangle by the heavy and descending features in spite of circulation. The shapes made from each UFM are reproduced in the process of human development and manifest respective facial shape through the self-reproduction method like fractal theory in the last. Conclusively. it is said that the facial form analysis method like EQAB type theory can be the useful methodology to understand the human pathological and physiological features in view of hydromechanics.

Effect of Argon Ion Beam Incident Angle on Self-Organized Nanostructure on the Surface of Polyethylene Naphthalate Film (알곤 이온빔 입사각에 따른 Polyethylene Naphthalate 필름 표면의 자가나노구조화 분석)

  • Joe, Gyeonghwan;Yang, Junyeong;Byeon, Eun-Yeon;Park, Young-Bae;Jung, Sunghoon;Kim, Do-Geun;Lee, Seunghun
    • Journal of the Korean institute of surface engineering
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    • v.53 no.3
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    • pp.116-123
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    • 2020
  • Ion beam irradiation induces self-organization of nanostructure on the surface of polymer film. We show that the incident angle of Ar ions on polyethylene naphthalate(PEN) film changes self-organized nanostructure. PEN film was irradiated by argon ion beams with the ion incident angle of 0°, 30°, 45°, 60°, and 80°. Nanostructure was altered from dimple to ripple structure as the angle increases. The ripple structure changed to pillar structure after 60°due to that the shallow incident angle increased the ion energy transfer per depth up to 50 eV/Å, which value could induce excessive surface heating and oligomer formation reacting as a physical mask for anisotropic etching. And quantitative analysis of the nanostructures was adapted by using ABC model and fractal dimension theory.

Development of Continuous Water Quality Monitoring System using the Daphnid Daphnia sp. (국내산 물벼룩 Daphnia sp.를 이용한 연속적인 수질모니터링 장치 개발)

  • Yoon, Sungjin;Lee, Sungkyu;Park, Hanoh
    • Journal of Korean Society on Water Environment
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    • v.24 no.1
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    • pp.36-43
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    • 2008
  • To develop the continuous water quality monitoring system using the daphnid Daphnia sp., the growth of test animal, sensitivity, and behaviour response of toxicants were observed. Growth of test animal significantly increased with increasing the food density under the 90~105 mg/L ($CaCO_3$) hardness, except the concentration of food (Chrollela sp.) was exceeded than optimal food supply. Behaviour responses of test animals were continuously analyzed by changes of fractal dimension value (FDV). The FDV sharply decreased after exposure to the concentrations of 0.13 mg/L copper, 0.06 mg/L lead, and 0.38 mg/L cadmium. In these concentrations, mortality and abnormal behaviour of daphnids exhibited within ca. 1.0-h after exposure. Comparison of 24-h $LC_{50}$ values with other zooplankton species indicated that sensitivity of the Daphnia sp. was higher than most zooplankton for lead, and brain shrimp, rotifer, and water flea (Ceriodaphnia dubia, D. magna) for copper, and brain shrimp, water flea (D. lumholzi), and amphipod for cadmium. Based on the above experimental results, significant relationship between toxicity and behaviour response of Daphnia sp. was supported the high potential of water quality monitoring system. Consequently, behavioural monitoring method in this study suggests a good estimation tool for detection of the discharged toxicants in water body and for ecotoxicological assessment aquatic organisms.

Applicability of a Space-time Rainfall Downscaling Algorithm Based on Multifractal Framework in Modeling Heavy Rainfall Events in Korean Peninsula (강우의 시공간적 멀티프랙탈 특성에 기반을 둔 강우다운스케일링 기법의 한반도 호우사상에 대한 적용성 평가)

  • Lee, Dongryul;Lee, Jinsoo;Kim, Dongkyun
    • Journal of Korea Water Resources Association
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    • v.47 no.9
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    • pp.839-852
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    • 2014
  • This study analyzed the applicability of a rainfall downscaling algorithm in space-time multifractal framework (RDSTMF) in Korean Peninsula. To achieve this purpose, the 8 heavy rainfall events that occurred in Korea during the period between 2008 and 2012 were analyzed using the radar rainfall imagery. The result of the analysis indicated that there is a strong tendency of the multifractality for all 8 heavy rainfall events. Based on the multifractal exponents obtained from the analysis, the parameters of the RDSTMF were obtained and the relationship between the average intensity of the rainfall events and the parameters of the RDSTMF was developed. Based on this relationship, the synthetic space-time rainfall fields were generated using the RDSTMF. Then, the generated synthetic space-time rainfall fields were compared to the observation. The result of the comparison indicated that the RDSTMF can accurately reproduce the multifractal exponents of the observed rainfall field up to 3rd order and the cumulative density function of the observed space-time rainfall field with a reasoable accuracy.

The long-term centimeter variability of active galactic nuclei: A new relation between variability timescale and black hole mass

  • Park, Jongho;Trippe, Sascha
    • The Bulletin of The Korean Astronomical Society
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    • v.41 no.1
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    • pp.36.2-37
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    • 2016
  • We study the long-term radio variability of 43 radio bright AGNs by exploiting the data base of the University of Michigan Radio Astronomy Observatory (UMRAO) monitoring program. The UMRAO database provides high quality lightcurves spanning 25 - 32 years in time at three observing frequencies, 4.8, 8, and 14.5 GHz. We model the periodograms (temporal power spectra) of the observed lightcurves as simple power-law noise (red noise, spectral power $P(f){\propto}f^{-{\beta}}$ using Monte Carlo simulations, taking into account windowing effects (red-noise leak, aliasing). The power spectra of 39 (out of 43) sources are in good agreement with the models, yielding a range in power spectral index (${\beta}$) from ${\approx}1$ to ${\approx}3$. We find a strong anti-correlation between ${\beta}$ and the fractal dimension of the lightcurves, which provides an independent check of the quality of our modelling of power spectra. We fit a Gaussian function to each flare in a given lightcurve to obtain the flare duration. We discover a correlation between ${\beta}$ and the median duration of the flares. We use the derivative of a lightcurve to obtain a characteristic variability timescale which does not depend on the assumed functional form of the flares, incomplete fitting, and so on. We find that, once the effects of relativistic Doppler boosting on the observed timescales are corrected, the variability timescales of our sources are proportional to the black hole mass to the power of ${\alpha}=1.70{\pm}0.49$. We see an indication for AGNs in different regimes of accretion rate, flat spectrum radio quasars and BL Lac objects, having different scaling relations with ${\alpha}{\approx}1$ and ${\approx}2$, respectively. We find that modelling the periodograms of four of our sources requires the assumption of broken powerlaw spectra. From simulating lightcurves as superpositions of exponential flares we conclude that strong overlap of flares leads to featureless simple power-law periodograms of AGNs at radio wavelengths in most cases (The paper is about to be submitted to ApJ).

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A Comparison of Three Fixed-Length Sequence Generators of Synthetic Self-Similar Network Traffic (Synthetic Self-Similar 네트워크 Traffic의 세 가지 고정길이 Sequence 생성기에 대한 비교)

  • Jeong, Hae-Duck J.;Lee, Jong-Suk R.
    • The KIPS Transactions:PartC
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    • v.10C no.7
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    • pp.899-914
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    • 2003
  • It is generally accepted that self-similar (or fractal) processes may provide better models for teletraffic in modern telecommunication networks than Poisson Processes. If this is not taken into account, it can lead to inaccurate conclusions about performance of telecommunication networks. Thus, an important requirement for conducting simulation studies of telecommunication networks is the ability to generate long synthetic stochastic self-similar sequences. Three generators of pseudo-random self-similar sequences, based on the FFT〔20〕, RMD〔12〕 and SRA methods〔5, 10〕, are compared and analysed in this paper. Properties of these generators were experimentally studied in the sense of their statistical accuracy and times required to produce sequences of a given (long) length. While all three generators show similar levels of accuracy of the output data (in the sense of relative accuracy of the Horst parameter), the RMD- and SRA-based generators appear to be much faster than the generator based on FFT. Our results also show that a robust method for comparative studies of self-similarity in pseudo-random sequences is needed.

Severity of Obstructive Sleep Apnea and Heart Rate Variability : Detrended Fluctuation Analysis (폐쇄성 수면 무호흡증의 심각도와 심박동 변이율 : 탈경향변동분석)

  • Ju, Gawon;Shin, Chul-Jin;Park, Doo-Heum
    • Korean Journal of Biological Psychiatry
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    • v.16 no.2
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    • pp.69-75
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    • 2009
  • Objectives : The detrended fluctuation analysis is one of the nonlinear methods for the investigation of biological time series. It quantifies the fractal scaling properties and is known to be useful in the evaluation of long-range correlations in time series. The heart rate variability(HRV) of obstructive sleep apnea syndrome (OSAS) patients during nighttime was analyzed by detrended fluctuation analysis to assess its relationship with the severity of the symptoms. Methods : Fifty nine untreated male OSAS patients with moderate to severe symptoms(mean age=45.4${\pm}$11.7 years, apnea-hypopnea index, AHI${\geq}$15) underwent nocturnal polysomnography. Moderate(AHI=15-30, N=22) and severe(AHI>30, N=37) OSAS patients were compared for the indices derived from detrended fluctuation analysis and frequency domain analysis of HRV. Results : In the detrended fluctuation analysis, the alpha values were 0.75${\pm}$0.11 and 0.82${\pm}$0.07 for the severe and the moderate OSAS groups respectively. The difference was significant(p<.01). The alpha value had negative correlation with AHI(r=-.425, p=.001). Negative correlation coefficients were also found in the relationships between the alpha values and very low frequency(VLF)(r=-.425, p=.001), low frequency(LF)(r=-.633, p= <.001) and the LF/HF ratio(r=-.305, p=.019) respectively. LF/HF ratio(p=.005) was higher in the severe OSAS group compared to that of the moderate OSAS group. Conclusion : In this study, the detrended fluctuation analysis showed the significant difference between the two OSAS groups classified according to their severity of symptoms. The scaling exponent showed the negative correlation with AHI and indicies of frequency domain analysis. This result suggests that detrended fluctuation analysis can be helpful to estimate the severity of OSAS.

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Digital Radiography Images Restoration with Wiener Filter in Wavelet Domain (웨이블릿영역에서 위너필터를 이용한 디지털 방사선 영상 복원)

  • Jeong, Jae-Won;Kim, Dong-Youn
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.46 no.6
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    • pp.58-64
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    • 2009
  • Digital radiography (DR) images are corrupted by the additive noise, and also distorted by system impulse response. These unwanted phenomena are obstacles to obtain the desired image. To recover the original image, we applied multiscale Wiener filters in wavelet domain for DR images. The multiscale Wiener filter is first proposed by Chen for the restoration of fractal signals which are distorted by the system impulse response and additive noise. In this paper, we extended the multiscale Wiener filter to the two dimensional data. To compare the performance of ours with others, some simulations are given for a couple of wavelet filters with different wavelet levels, system impulse reponses and various noise power. When the addive noise powers are between 20-32 dB, the signal to noise ratio(SNR) of the proposed system is 0.5-2.0 dB better than that of the traditional Wiener filter method.

Implementation of the Vehicle Antenna for the AM/FM/TDMB/GPS Receiver (AM/FM/TDMB/GPS 수신용 전장 안테나 제작)

  • Kim, Joo-Man;Son, Tae-Ho
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.8 no.5
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    • pp.105-113
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    • 2009
  • In this paper, a vehicle antenna for AM, FM, TDMB, GPS systems was designed and implemented. AM antenna loaded into small space of shark shape was designed by ferrite turn style antenna. For the FM and TDMB antenna, folded monopole antenna which helical is folded was applied. GPS antenna for achieving characteristics both bandwidth and gain improvement was designed microstrip patch that has air substrate and fractal structure. Receiving signal strengths by the measurement were presented for the AM, FM and TDMB antenna. AM signal strength was -65.7dBm, this strength is almost as same conventional pole antenna as -63.4dBm. It can be replaced conventional pole or glass antenna by the studied antenna. Signal strengths for FM and TDMB were -55.66 and -43.50dBm at center frequency, they are 5~10dB higher than conventional antenna. Measurements of bandwidth and gain for the GPS antenna showed 135 MHz under VSWR 2 : 1 and 4.31dBi, gains over GPS band were 3~5dB higher than ceramic patch antenna.

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A Study on Hybrid Characteristics in the Work of Chinese Rising Fashion Designers (중국 신진 패션 디자이너의 작품에 나타난하이브리드 특성 연구)

  • Bin, Sen;Yum, Haejung
    • Journal of Fashion Business
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    • v.24 no.1
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    • pp.1-14
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    • 2020
  • Based on the trend of pluralization and globalization the collapse of national borders now is a manifestation of mixed and compromised cultures and societies. It is also emerging as a hybrid fashion in fashion. Hybrid fashion means creating a new image by mixing various cultures beyond the time and space. This study aims to analyze the current state of Chinese fashion design and present its direction by grasping the characteristics of hybrids in the works of rising Chinese fashion designers in the era of pluralization. The research method was literature review and empirical research. According to the selection criteria of new fashion designers, 6 new fashion designers of 5 fashion brands were selected and their total 458 points works were analyzed. The analysis results are as follows. First, most of the time trade-offs were 'past and present' trade-offs that express Chinese traditional culture and the image of the past with modern design. The trade-offs between 'present and future' is expressed by mixing print patterns, colors and light with fractal art. Second, spatial trade-offs was expressed in the way of expressing Chinese themes in the composition of western clothing, expressing the Western themes in oriental colors, and inspired by Japanese culture expressed by deconstructionism, Third, the gender mix mainly used dark embroidery on women's clothing, while the men's wear showed a delicate feminine charm with a surreal pattern on thin and transparent gauze fabric.