• Title/Summary/Keyword: asymmetric changes

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Effect of Cervical Manipulation on Blood Velocity and Flow in Subjects with Asymmetric Vertebral Artery (경추 도수교정이 추골동맥 비대칭군의 혈류속도와 혈류량에 미치는 영향)

  • Kim, Han-Il;Kim, Ho-Bong
    • The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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    • v.19 no.2
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    • pp.31-37
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    • 2013
  • Background: The purpose of this study was to identify the effects of cervical manipulation for improve blood velocity and flow in the subjects with asymmetric vertebral artery. Methods: Twenty-four subjects on asymmetric vertebral artery with right side have less blood flow than left side participated in this study for apply to non-specific cervical manipulation on lower portion. Measurement method were using duplex ultrasound with colour doppler imaging for blood velocity and flow on left and right vertebral artery. Results: Compared changes of blood velocity and flow on unilateral after the cervical manipulation, the left blood velocity decreased significantly (p<.01) and the right blood velocity increased significantly (p<.01). The left blood flow no significant changes and the right blood flow increased significantly (p<.01). Compared changes of blood velocity and flow on bilateral, the left and right blood velocity and flow made significantly difference on pre-manipulation (p<.01). However, both side no significantly difference on post-manipulation. Conclusions: These findings suggest that the non-specific cervical manipulation took effect for improve blood velocity and flow in the subjects with asymmetric vertebral artery. Therefore, therapeutic approaches for improve to asymmetric vertebral artery should be consider non-specific cervical manipulation.

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Asymmetric Information Spillovers between Trading Volume and Price Changes in Malaysian Futures Market

  • Go, You-How;Lau, Wee-Yeap
    • The Journal of Asian Finance, Economics and Business
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    • v.1 no.3
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    • pp.5-16
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    • 2014
  • This study aims to examine the dynamics of price changes and trading volume of Kuala Lumpur Options and Financial Futures Exchange (KLOFFE) from 2000 to 2008. With augmented analysis, our results support two hypotheses. First, under information spillover, our findings support noise traders' hypothesis as the time span for variance of past trading volume to cause variance of current return is found to be asymmetric under bull and bear markets. Second, looking at the dynamic relation between volume and volatility of price changes, our findings support Liquidity-Driven Trade hypothesis as past trading volume and subsequent volatility of return exhibit positive correlation. In terms of investors' behavior in response to the news, we find that investors are more risk taking in bull market and more risk reverse in bear market. Our study suggests that investors should adjust their strategy in the futures market in a dynamic manner as the time span of new information arrival is not consistent. Also, uninformed investors with information asymmetry should expect noninformational trading from informed investors to establish their desired positions for better liquid position.

Experimental study on the asymmetric impact loads and hydroelastic responses of a very large container ship

  • Lin, Yuan;Ma, Ning;Gu, Xiechong;Wang, Deyu
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.12 no.1
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    • pp.226-240
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    • 2020
  • This paper presents an experimental investigation of asymmetric impact effects on hydroelastic responses. A 1:64 scaled segmented ship model with U-shape open cross-section backbone was newly designed to meet elastic similarity conditions of vertical, horizontal and torsional stiffness simultaneously. Different wave heading angles and wavelengths were adopted in regular wave test. In head wave condition, parametric rolling phenomena happened along with asymmetric slamming forces, the relationship between them was disclosed at first time. The impact forces on starboard and port sides showed alternating asymmetric periodic changes. In oblique wave condition, nonlinear springing and whipping responses were found. Since slamming phenomena occurred, high-frequency bending moments became an important part in total bending moments and whipping responses were found in small wavelength. The wavelength and head angle are varied to elucidate the relationship of springing/whipping loads and asymmetric impact. The distributions of peaks of horizontal and torsional loads show highly asymmetric property.

POSTEROANTERIOR CEPHALOMETRIC STUDY OF FACIAL ASYMMETRY ABOUT CLINICAL CHARACTERISTICS AND CHANGES AFTER ORTHOGNATHIC SURGERY (안모비대칭환자의 임상적 특성 및 악교정수술후 변화에 관한 연구;정모두부방사선 규격사진의 계측을 중심으로)

  • Choi, You-Sung;Lee, Sang-Chull
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.18 no.3
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    • pp.396-410
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    • 1996
  • This study was carried out to evaluate the distribution and the degree of the asymmetry existed in normal persons and asymmetric patients, and to investigate the changes of asymmetric patients after orthognathic surgery. The analysis was performed with the posteroanterior cephalometric radiography of 60 normal persons and 31 facial asymmetric patients. The results were as follows : 1. The degree of normal asymmetry existed in normal persons was not significant except MF and Me measurements. 2. The degree of normal asymmetry according to sex difference was not significant except cranial base area. 3. When normal persons were compared to asymmetric patients, there were more measurements which presented significant asymmetry on mandible than on maxilla. 4. When postoperative state was compared to preoperative state, the degree of asymmetry were usually decreased except AGO and GA measurements, especially the Cd, MF, Me, and Cd-Me measurements decreased significantly. 5. When postoperative state was compared to normal persons, 4 measurements of mandible approached significantly the measurements of normal persons.

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Effect of Asymmetric Hot Rolling on the Texture Evolution of Fe-3%Si Steel

  • Na, Tae-Wook;Park, Hyung-Ki;Park, Chang-Soo;Joo, Hyung-Don;Park, Jong-Tae;Han, Heung Nam;Hwang, Nong-Moon
    • Metals and materials international
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    • v.24 no.6
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    • pp.1369-1375
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    • 2018
  • In Fe-3%Si steel, the hot rolling process affects not only the hot rolling texture but also the primary recrystallization texture. Here, the effect of asymmetric hot rolling was studied by comparing the difference in the texture evolved between asymmetric and symmetric hot rolling. The effect of asymmetric hot rolling on the texture of primary recrystallized Fe-3%Si steel was also studied. The symmetric hot rolling of Fe-3%Si steel produces a rotated cube texture at the center but Goss and copper textures near the surface. Asymmetric hot rolling tends to produce Goss and copper textures even at the center like the texture near the surface. After primary recrystallization, the dominant texture at the center changes from {001} <210> to {111} <112> and the new texture has a higher fraction of the grains which make the low energy boundary with Goss grains than that of symmetric hot rolling.

Symmetric and Asymmetric Approaches to Money Demand Determination in Indonesia: Is Divisia Money Relevant?

  • LEONG, Choi-Meng;PUAH, Chin-Hong;TANG, Maggie May-Jean
    • The Journal of Asian Finance, Economics and Business
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    • v.8 no.7
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    • pp.393-402
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    • 2021
  • This study aims to examine whether symmetric effects or asymmetric effects of exchange rates exist in determining the money demand in Indonesia. Simple-sum money and Divisia money were included in different models for comparison due to the financial developments in Indonesia. This study uses time-series data from 1996Q1 to 2019Q4 for the estimation. The nonlinear autoregressive distributed lag (NARDL) model is utilized to verify the asymmetric effects of exchange rates on money demand. The Augmented Dickey-Fuller and Phillips-Perron unit root tests were performed to verify the order of integration of the variables. The findings of this study revealed that the exchange rate is one of the most important determinants of money demand in Indonesia and the effect is asymmetric. The findings further indicated that money demand function, which incorporates Divisia monetary aggregate is parsimonious. Monetary targets such as money supply and interest rates are critical for monetary policy conduct to achieve inflation levels set by government. As the adoption of an inflation targeting framework needs to be in keeping with the flexible exchange rate system, the asymmetric effect of exchange rate changes can be used in exchange rate policy conduct to achieve financial system and price stability.

Dynamic Instability and Instantaneous Frequency of a Shallow Arch With Asymmetric Initial Conditions (비대칭 초기 조건을 갖는 얕은 아치의 동적 불안정과 순시 주파수 변화)

  • Shon, Sudeok;Ha, Junhong
    • Journal of Korean Association for Spatial Structures
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    • v.20 no.2
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    • pp.77-85
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    • 2020
  • This paper examined the dynamic instability of a shallow arch according to the response characteristics when nearing critical loads. The frequency changing feathers of the time-domain increasing the loads are analyzed using Fast Fourier Transformation (FFT), while the response signal around the critical loads are analyzed using Hilbert-Huang Transformation (HHT). This study reveals that the models with an arch shape of h = 3 or higher exhibit buckling, which is very sensitive to the asymmetric initial conditions. Also, the critical buckling load increases as the shape increases, with its feather varying depending on the asymmetric initial conditions. Decomposition results show the decrease in predominant frequency before the threshold as the load increases, and the predominant period doubles at the critical level. In the vicinity of the critical level, sections rapidly manifest the displacement increase, with the changes in Instantaneous Frequency (IF) and Instant Energy (IE) becoming apparent.

The Effects of Asymmetric Bag Carrying during Walking on Plantar Pressure (보행 시 비대칭성 가방 휴대가 족저압에 미치는 영향)

  • Park, Soo-Jin;Lee, Jung-Ho;Kim, Jin-Sang
    • Journal of the Korean Society of Physical Medicine
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    • v.7 no.4
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    • pp.459-469
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    • 2012
  • PURPOSE: The purpose of the present study was to examine changes caused by asymmetric bag carrying methods to carry the bag with one shoulder only to plantar pressure during walking. METHODS: Twenty three normal adults without any gait problem participated in the present study. Experimental conditions used consisted of walking without carrying any bag(condition 1), walking wearing a bag on both shouders (condition 2), and walking wearing a bag on the right shoulder(condition 3) and the weight of the bag was set to 15% of each subject's body weight. All the subjects were instructed to participate in all experiments under these three conditions and plantar pressures were measured from the subjects' right and left feet using an F-scan system while the subjects were walking under the three conditions. To analyze the measured plantar pressure, the sole was divided into seven areas (Hallux, Toe, Met1, Met23, Met45, Mid foot and Heel) and maximum plantar pressures in individual areas were measured. RESULTS: The results of measurement of plantar pressures under three walking conditions did not show significant changes in any areas of the left and right feet except for the mid foot area of the right food. The asymmetry between the left and right feet was examined and the results showed significant differences only in area Met23 under condition 2 and did not show significant differences in any other areas. CONCLUSION: On comprehensively considering the results of the present study, it could be seen that asymmetric bag carrying did not have large effects on changes in plantar pressure during walking compared to symmetric carrying. The reason for this is considered to be posture adjusting mechanisms against load positions.

Analysis of Static Stability by Modified Mathematical Model for Asymmetric Tractor-Harvester System: Changes in Lateral Overturning Angle by Movement of Center of Gravity Coordinates

  • Choi, Kyu-hong;Kim, Seong-Min;Hong, Sungha
    • Journal of Biosystems Engineering
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    • v.42 no.3
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    • pp.127-135
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    • 2017
  • Purpose: Purpose: The usability of a mathematical model modified for analysis of the static stability of an asymmetric tractor-harvester system was investigated. Method: The modified asynchronous mathematical model was validated through empirical experiments, and the effects of movements of the center of gravity (CG) coordinates on the stability against lateral overturning were analyzed through simulations. Results: Changes in the lateral overturning angle of the system were investigated when the coordinates of the CG of the system were moved within the variable range. The errors between simulation results and empirical experiments were compared, and the results were -4.7% at the left side overturning and -0.1% at the right side overturning. The asymmetric system was characterized in such a way that the right side overturning had an increase in overturning angle in the (+) variable range, while it had a decrease in overturning angle in the (-) variable range. In addition, the left side overturning showed an opposite result to that of the right side. At the declination angle (296<${\gamma}$<76), the right side overturning had an increase in the maximum overturning angle of 3.6%, in the minimum overturning angle of 20.3%, and in the mean overturning angle of 15.9%. Furthermore, at the declination angle (284<${\gamma}$<64), the left side overturning had a decrease in the maximum overturning angle of 29.2%, in the minimum overturning angle of 44%, and in a mean overturning angle of 39.7%. Conclusion: The modified mathematical model was useful for predicting the overturning angle of the asymmetric tractor-harvester system, and verified that a movement of the CG coordinates had a critical effect on its stability. In particular, the left side overturning was the most vulnerable to stability, regardless of the direction of declination angle.

Empirical Analyses of Asymmetric Conditional Heteroscedasticities for the KOSPI and Korean Won-US Dollar Exchange Rate (KOSPI지수와 원-달러 환율의 변동성의 비대칭성에 대한 실증연구)

  • Maeng, Hye-Young;Shin, Dong-Wan
    • The Korean Journal of Applied Statistics
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    • v.24 no.6
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    • pp.1033-1043
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    • 2011
  • In this paper, we use a nested family of models of Generalized Autoregressive Conditional Heteroscedasticity(GARCH) to verify asymmetric conditional heteroscedasticity in the KOSPI and Won-Dollar exchange rate. This study starts from an investigation of whether time series data have asymmetric features not explained by standard GARCH models. First, we use kernel density plot to show the non-normality and asymmetry in data as well as to capture asymmetric conditional heteroscedasticity. Later, we use three representative asymmetric heteroscedastic models, EGARCH(Exponential Garch), GJR-GARCH(Glosten, Jagannathan and Runkle), APARCH(Asymmetric Power Arch) that are improved from standard GARCH models to give a better explanation of asymmetry. Thereby we highlight the fact that volatility tends to respond asymmetrically according to positive and/or negative values of past changes referred to as the leverage effect. Furthermore, it is verified that how the direction of asymmetry is different depending on characteristics of time series data. For the KOSPI and Korean won-US dollar exchange rate, asymmetric heteroscedastic model analysis successfully reveal the leverage effect. We obtained predictive values of conditional volatility and its prediction standard errors by using moving block bootstrap.