• Title/Summary/Keyword: occurrences

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THE PERIODICITY OF THE SOLAR FLARE PRODUCTION DURING THE ACTIVITY CYCLE 22

  • TOHMURA ICHIROH;TOKIMASA NORITAKA;KUBOTA JUN
    • Journal of The Korean Astronomical Society
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    • v.29 no.spc1
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    • pp.321-322
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    • 1996
  • Using the data on the occurrences of the Ho: and soft X-ray flares for the time interval of January 1, 1986-May :31, 1994, we have studied the middle term(30-300days) pericities of the solar flare production during the activity cycle 22. Power analysis of the time seies of daily H$\alpha$ flare index in the northern hemisphere shows prominent periodicities at 220, 120, 109, and 92 days(see Figures l(a) and l(b)), while in the southern hemisphere, those at 267, 213, 183, 167, and 107 days are apparent, though their peaks are not so distint as those in the northern hemisphere. Periodogram of daily soft X-ray flare index also reveal the periodicities at 279, 205, 164, 117, and 91 days in the northern hemisphere, and at 266, 220, 199, 162, 120, and 100 days in the southern hemisphere. Howeer, the 155-day periodicity reported for the earlier cycles, 19, 20, and 21, could not be confirmed in our analysis. to be submitted to Solar Physics; an extended abstract.

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A Visual and Contextual Comparative Study of the Work of Picasso and Chanel Towards an Understanding of the Overlaps Between Modern Art and Fashion

  • Forster, Samantha Vettese
    • International Journal of Costume and Fashion
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    • v.12 no.2
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    • pp.15-32
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    • 2012
  • From the beginning of the twentieth century, 'Modernism' impacted and transformed art and clothing. Pablo Picasso and Gabrielle 'Coco' Chanel were two of the most central characters in Modernism working simultaneously in their disciplines. Picasso's innovations, particularly in abstract art and Chanel's fashion designs, that dramatically departed from the previous corseted and highly decorative styles, were so significant that they have left an influence on contemporary art and fashion. This study will compare their visual works and documented evidence of their motivations, within the context of their cultural backgrounds, to reveal meaning in the occurrences of overlaps. This approach has examined the historical, cultural background of the artist and designer's environment from different perspectives, adding to previous research in this area. Through this research, outcomes of the analysis have shown similarities and divergences in the wider genres of art and fashion and the practice of the artist and fashion designer. The reference list to this text, used in the survey, gives a comprehensive overview of pertinent publications disseminating Picasso and Chanel's visual works, oral perspectives and cultural impact.

Harmonic Resonances of Continuous Rotor with Nonlinearity and Internal Resonances (비선형 연속축의 조화진동 및 내부공진)

  • Lee, Seong-U;Kim, Gwang-Rae;Son, Bong-Se
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.24 no.10 s.181
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    • pp.2413-2419
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    • 2000
  • Harmonic resonances in a continuous rotating shaft with distributed mass are discussed. The restoring force of the shaft has geometric stiffening nonlinearity due to the extension of the shaft centerline. The effect of a distributed lateral force, such as the gravity, is assumed. The possibility of the occurrences of harmonic resonances, the shapes of resonance curves, and internal resonance phenomena are investigated.

Bifurcation Analysis of a Non-linear Hysteretic Oscillating System (비선형 히스테리시스 진동시스템의 분기해석)

  • 송덕근;최진권;장서일
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2001.05a
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    • pp.289-294
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    • 2001
  • Three kinds of viscoelastic damper model, which has a non-linear spring as an element is studied analytically and numerically. The behavior of the damper model shows non-linear hysteresis curves which is qualitatively similar to those of real viscoelastic materials. The motion is governed by a non-linear constitutive equation and an additional equation of motion. Harmonic balance method is applied to get analytic solutions of the system. The frequency-response curves show that multiple solutions co-exist and that the jump phenomena can occur. In addition, it is shown that separate solution branch exists and that it can merge with the primary response curve. Saddle-node bifurcation sets explain the occurrences of such non-linear phenomena.

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Strain localization and failure load predictions of geosynthetic reinforced soil structures

  • Alsaleh, Mustafa;Kitsabunnarat, Akadet;Helwany, Sam
    • Interaction and multiscale mechanics
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    • v.2 no.3
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    • pp.235-261
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    • 2009
  • This study illustrates the differences between the elasto-plastic cap model and Lade's model with Cosserat rotation through the analyses of two large-scale geosynthetic-reinforced soil (GRS) retaining wall tests that were brought to failure using a monotonically increasing surcharge pressure. The finite element analyses with Lade's model were able to reasonably simulate the large-scale plane strain laboratory tests. On average, the finite element analyses gave reasonably good agreement with the experimental results in terms of global performances and shear band occurrences. In contrast, the cap model was not able to simulate the development of shear banding in the tests. In both test simulations the cap model predicted failure loads that were substantially less than the measured ones.

Seismic analysis of transmission towers under various line configurations

  • Lei, Y.H.;Chien, Y.L.
    • Structural Engineering and Mechanics
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    • v.31 no.3
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    • pp.241-264
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    • 2009
  • In this paper, the dynamic behavior for a group of transmission towers linked together through electrical wires and subjected to a strong ground motion will be investigated in detail. In performing the seismic analysis, the wires and the towers concerned are modeled, respectively, by using the efficient cable elements and the 3-D beam elements both considering geometric nonlinearities. In addition, to enhance the reliability and applicability of analytical outcome, a sophisticated soil-structure interaction model will be utilized in analyses. The strength capacities and the fracture occurrences for the main members of the tower are examined with the employment of the appropriate strength interaction equations. It is expected that by aid of this investigation, those who are engaged in code constitution or in practical designing of transmission towers may gain a better insight into the roles played by the interaction force between towers and wires and by the configurations of transmission lines under strong earthquake.

Behaviour of vertically and horizontally loaded pile and adjacent ground affected by tunnelling

  • Oh, Dong-Wook;Ahn, Ho-Yeon;Lee, Yong-Joo
    • Geomechanics and Engineering
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    • v.15 no.3
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    • pp.861-868
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    • 2018
  • Recent occurrences of earthquakes in Korea have increased the importance of considering how horizontal loads affect foundation structures as a result of wind and dynamic impact. However, to date, there are few studies on tunnelling-induced behaviour of ground and pile structures simultaneously subjected to horizontal and vertical loads. In this research, therefore, the behaviour of ground and single piles due to tunnelling were investigated through a laboratory model test. Three cases of horizontal loads were applied to the top of the pile. In addition, a numerical analysis was carried out to analyse and compare with the results from the laboratory model test.

Development of Probabilistic-Fuzzy Model for Seismic Hazard Analysis (지진예측을 위한 확률론적퍼지모형의 개발)

  • 홍갑표
    • Computational Structural Engineering
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    • v.4 no.3
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    • pp.107-115
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    • 1991
  • A probabilistic-Fuzzy model for seismic hazard analysis is developed. The proposed model is able to reproduce both the randomness and the imprecision in conjunction with earthquake occurrences. Results-of this research are (a) membership functions of both peak ground accelerations associated with a given probability of exceedance and probabilities of exceedance associated with a given peak ground acceleration, and (b) characteristic values of membership functions at each location of interest. The proposed probabilistic-fuzzy model for assessment of seismic hazard is successfully applied to the Wasatch Front Range in Utah in order to obtain the seismic maps for different annual probabilities of exceedance, different peak ground accelerations, and different time periods.

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Experiment on the Anomalous Animal Behaviors by Electric Field Effects for detecting Earthquake Precursors (지진전조현상 파악을 위한 전기장 효과에 의한 동물 이상 행동 실험)

  • 경재복;윤장근
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 2001.09a
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    • pp.57-64
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    • 2001
  • There are some previous reports that some animals such as rats and birds move in a large group and act abnormally to avoid the large earthquake. This study is to experimentally testify what relations exist between the anomalous animal behavior and electric field effect, which is reported due to the piezoelectric effects in a basement rock before earthquake occurrences. When electric field is applied to the whole bottom of the cage, they show nervous behaviors such as grooming, washing their faces, standing on legs or running around in panic to avoid the electric field. When more strong electric field is applied, they jump with shrieking and mount on the electric line. The rat shows more sensitive anomalous behavior than the bird. Even though the current to the experimental birds and rats is just a few $\mu$A, they react in various ways. The anomalous animal behaviors under the small ground electric field may have some relations to the actual phenomena before great earthquake. This kind of study is quite worthy for the understanding of earthquake precursors.

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A Study of Measuring Forecasting Accuracy Under Rromotion System (인위적인 수요창출 하에서 서비스부품의 수요예측의 정확도)

  • Rhee, Young
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.33 no.3
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    • pp.10-21
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    • 2010
  • Promotion system can be used as strategical management weapon to enhance the sales power. Planned order system has some similarities with promotion system to create purchasing power and to supply the service parts with low price on purpose. The only difference is whether it is prearranged event or not. The effectiveness of forecasting has increased with normal state of ordering process. However, the accuracy of forecasting has diminished with irregular state of ordering, such as demand occurrences by unexpected climate change or intended planned order by the company. A planned order system is examined through the process of computing the effectiveness on the basis of forecasting in this paper. And it is suggested that how to increase the accuracy of forecasting capability under the planned order system.