• Title/Summary/Keyword: asymmetric changes

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Texture and Plastic Strain Ratio Changes of Hot Asymmetrically Rolled AA3003 Sheet (열간 비대칭 압연한 AA3003 판재의 집합조직과 소성변형비 변화)

  • Hamrakulov, B.;Lee, C.W.;Kim, I.
    • Transactions of Materials Processing
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    • v.28 no.5
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    • pp.281-286
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    • 2019
  • The plastic strain ratio is one of the factors of the deep drawability of metal sheets. The plastic strain ratio of Al sheet is low value. Therefore, it is necessary to increase the plastic strain ratio in order to improve the deep draw ability of the Al sheet. This study investigated the increase of the plastic strain ratio and the texture change of AA3003 sheet after the hot asymmetric rolling. The average plastic strain ratio of the initial AA3003 sheets was 0.69. After 83% hot asymmetric rolling at $200^{\circ}C$, the average plastic strain ratio was 0.83. The average plastic strain ratio of the 83% hot asymmetrically rolled AA3003 sheet at $200^{\circ}C$ is 1.2 times higher than that of the initial AA3003 sheet. The ${\mid}{\Delta}R{\mid}$ of 83% hot asymmetrically rolled AA3003 sheet at $200^{\circ}C$ is 0.83 times lower than that of the initial AA3003 sheet. This result is due to the development of the intensity of ${\gamma}-fiber$ texture and reduces the intensity of {001}<110> and {001}<100> textures after hot asymmetric rolling of AA3003 sheet.

Three-dimensional evaluation of mandibular width after mandibular asymmetric setback surgery using sagittal split ramus osteotomy

  • Seong-Sik Kim;Sung-Hun Kim;Yong-Il Kim;Soo-Byung Park
    • The korean journal of orthodontics
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    • v.53 no.2
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    • pp.99-105
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    • 2023
  • Objective: The study aimed to evaluate the changes in mandibular width after sagittal split ramus osteotomy (SSRO) in patients with mandibular asymmetric prognathism using cone-beam computed tomography (CBCT). Methods: Seventy patients who underwent SSRO for mandibular setback surgery were included in two groups, symmetric (n = 35) and asymmetric (n = 35), which were divided according to the differences in their right and left setback amounts. The mandibular width was evaluated three-dimensionally using CBCT images taken immediately before surgery (T1), 3 days after surgery (T2), and 6 months after surgery (T3). Repeated measures analysis of variance was applied to verify the differences in mandibular width statistically. Results: Both groups showed a significant increase in the mandibular width at T2, followed by a significant decrease at T3. No significant difference was observed between T1 and T3 in any of the measurements. No significant differences were found between the two groups (p > 0.05). Conclusions: After mandibular asymmetric setback surgery using SSRO, the mandibular width increased immediately but returned to its original width 6 months after surgery.

Bayesian inference on multivariate asymmetric jump-diffusion models (다변량 비대칭 라플라스 점프확산 모형의 베이지안 추론)

  • Lee, Youngeun;Park, Taeyoung
    • The Korean Journal of Applied Statistics
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    • v.29 no.1
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    • pp.99-112
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    • 2016
  • Asymmetric jump-diffusion models are effectively used to model the dynamic behavior of asset prices with abrupt asymmetric upward and downward changes. However, the estimation of their extension to the multivariate asymmetric jump-diffusion model has been hampered by the analytically intractable likelihood function. This article confronts the problem using a data augmentation method and proposes a new Bayesian method for a multivariate asymmetric Laplace jump-diffusion model. Unlike the previous models, the proposed model is rich enough to incorporate all possible correlated jumps as well as mention individual and common jumps. The proposed model and methodology are illustrated with a simulation study and applied to daily returns for the KOSPI, S&P500, and Nikkei225 indices data from January 2005 to September 2015.

THE CORRECTION OF CLASS III MANDIBULAR ASYMMETRY USING BILATERAL SAGITTAL SPLIT RAMUS OSTEOTOMY AND LATERAL ANGLE REDUCTION (외측 하악각 골절제술을 동반한 시상분할골절단술을 통한 골격성 3급 하악골 비대칭 환자의 치료)

  • Kang, Hee-Jea;Song, In-Woo;Kang, Yung-Ki;Kim, Jong-Ryoul
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.32 no.2
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    • pp.132-140
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    • 2010
  • Purpose: The aim of this study is to identify the usefulness of unilateral mandibular angle ostectomy, so-called "Lateral Angle Reduction", in asymmetric prognathism patients by the assessment of postoperative stability and esthetic results Patients and methods: For the retrospective study, 10 skeletal class III mandibular asymmetry patients who were performed SSRO and unilateral mandibular angle ostectomy, Lateral Angle Reduction, was selected. Lateral and posterioanterior cephalogram was taken before surgery (T0), 1day after surgery (T1) and 6month after surgery (T2). To know the esthetic results the facial width and lateral facial contour were examined on posterioanterior cephalogram and to know the postoperative stability B point and Incisor inferius was examined on lateral cephalogram. Statistical analysis was performed. Results: From T0 to T1, Intergonial width was significantly decreased, dominantly at shortened side but no significant changes at lengthened side. Those were well-maintained during 6 months. Lateral facial angle and Ramus angle was significantly decreased on only shortened side from T0 to T1. As a result, after surgery, there were no significant differences in all measurements between shortened side and lengthened side. Ramus deviation angle in shortened side and ramus angle in lengthened side which reflect the angulation of ramus on frontal plane didn't show significant changes after surgery and during postsurgical periods. Lower dental midline showed no statistical changes during postsurgical period. The relapse rate on B-point was 11.92%. Conclusion: Unilateral "Lateral angle reduction" in the asymmetric mandible is valuable to obtain the narrow lower face and symmetric facial contour with a good stability.

Relationship between plasma asymmetric dimethylarginine and nitric oxide levels afects aerobic exercise training-induced reduction of arterial stifness in middle-aged and older adults

  • Shimomura, Mio;Fujie, Shumpei;Sanada, Kiyoshi;Kajimoto, Hiroki;Hamaoka, Takafumi;Iemitsu, Motoyuki
    • Korean Journal of Exercise Nutrition
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    • v.25 no.1
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    • pp.16-22
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    • 2021
  • [Purpose] Aerobic exercise training (AT) reverses aging-induced deterioration of arterial stiffness via increased arterial nitric oxide (NO) production. Asymmetric dimethylarginine (ADMA), an endogenous inhibitor of NO synthase, was decreased by AT. However, whether AT-induced changes in ADMA levels are related to changes in nitrite/nitrate (NOx) levels remains unclear. Accordingly, we aimed to clarify whether the relationship between plasma ADMA and NOx levels afected the AT-induced reduction of arterial stifness in middle-aged and older adults. [Methods] Thirty-one healthy middle-aged and older male and female subjects (66.4 ± 1.3 years) were randomly divided into two groups: exercise intervention and sedentary controls. Subjects in the training group completed an 8-week AT (60%-70% peak oxygen uptake [${\dot{V}}O_{2peak}$] for 45 min, 3 days/week). [Results] AT signifcantly increased ${\dot{V}}O_{2peak}$ (P < 0.05) and decreased carotid β-stifness (P < 0.01). Moreover, plasma ADMA levels were significantly decreased while plasma NOx levels and NOx/ADMA ratio were significantly increased by AT (P < 0.01). Additionally, no sex diferences in AT-induced changes of circulating ADMA and NOx levels, NOx/ADMA ratio, and carotid β-stifness were observed. Furthermore, the AT-induced increase in circulating ADMA levels was negatively correlated with an increase in circulating NOx levels (r = -0.414, P < 0.05), and the AT-induced increase in NOx/ADMA ratio was negatively correlated with a decrease in carotid β-stifness (r = -0.514, P < 0.01). [Conclusion] These results suggest that the increase in circulating NOx with reduction of ADMA elicited by AT is associated with a decrease in arterial stiffness regardless of sex in middle-aged and older adults.

A Study on Asymmetric Price Adjustment in Domestic Petroleum Market (국내 석유시장에서 비대칭 가격조정에 관한 연구)

  • Kim, Jin Hyung
    • Environmental and Resource Economics Review
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    • v.24 no.3
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    • pp.523-549
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    • 2015
  • This paper investigates an oil refiner's asymmetric behavior in the adjustments of gasoline and diesel prices to changes in his own price and his rivals' prices as well as input costs. An asymmetric error correction model which allows a firm's pricing behavior to the deviation of other firms' prices from their long-run equilibrium level is employed for estimation using weekly data for the period April 2009 to January 2015. Evidence is found that there is a significant degree of asymmetry in the adjustment of wholesale prices to changes in crude oil price. A similar result in regard to the exchange rate is also found by the data. The estimation results for firm's response to changes in other firms' prices indicates that implicit collusion could be more easily exploited in the wholesale petroleum market as results of firms' interaction with each other and anticipation of rivals' pricing behavior. A few refiners show competitive price adjustment in response to the upward deviation of the others' prices from their equilibrium level.

Asymmetric Impacts of Oil Price Uncertainty on Industrial Stock Market -A Quantile Regression Approach - (분위수회귀분석을 이용한 유가 변동성에 대한 산업별 주식시장의 이질적 반응 분석)

  • Joo, Young-Chan;Park, Sung-Yong
    • Management & Information Systems Review
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    • v.38 no.3
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    • pp.1-19
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    • 2019
  • This paper investigates the asymmetric effects of crude oil price uncertainty on industrial stock returns under different market conditions (bearish and bullish stock markets). We consider a quantile regression method using monthly oil volatility index, KOSPI and 22 industrial stock indices from May 2007 to February 2019. Especially, we take care of the positive and negative changes of the oil volatility index to analyze asymmetric effects of the oil price uncertainty for the bearish and bullish stock market conditions. During the bearish markets, the oil volatility index has relatively strong statistically significant negative effects on the industrial stock returns. These effects gradually decrease when the market conditions became more bullish markets. In particular, positive changes in the oil volatility index yields a further significant decrease in 12 industrial stock returns during the extreme bearish markets. Moreover, during the bullish markets, negative changes in the oil volatility index have statistically significant negative effects on the 12 industrial stock returns. From the empirical results, we see that participants of the Korean stock market are sensitive to bad news in a recession.

Changes of Texture and Plastic Strain Ratio of Asymmetrically Rolled and Annealed Cu Sheet (I) (비대칭 압연과 열처리한 Cu 판의 집합조직과 소성변형비 변화 (I))

  • Lee, C.W.;Lee, D.N.;Kim, I.
    • Transactions of Materials Processing
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    • v.28 no.6
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    • pp.354-360
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    • 2019
  • The plastic strain ratio is one of the factors that affect the deep drawability of metal sheets. The plastic strain ratio of fully annealed Cu sheet is low because its texture has {001}<100>. In order to improve the deep drawability of Cu sheet, it is necessary to increase the plastic strain ratio of Cu sheet. This study investigate the increase of plastic strain ratio of a Cu sheet after the first asymmetry rolling and annealing, and the second asymmetry rolling and annealing in air and Ar gas conditions. The average plastic strain ratio (Rm) was 0.951 and |ΔR| value was 1.27 in the initial Cu sheet. After the second 30.1% asymmetric rolling and annealing of Cu sheet at 1000℃ in air condition, the average plastic strain ratio (Rm) was 1.03 times higher. However, |ΔR| was 0.12 times lower than that of the initial specimen. After the second 18.8% asymmetric rolling and annealing of Cu sheet at 630℃ in Ar gas condition, the average plastic strain ratio (Rm) was 1.68 times higher and |ΔR| was 0.82 times lower than that of the initial specimen. These results are attributed to the change of the texture of Cu sheet due to the different annealing conditions.

Influence of Asymmetric Aerodynamic Loading on Multiple Unit Floating Offshore Wind Turbine (부유식 다수 풍력 발전기에 작용하는 비대칭 공력 하중의 영향)

  • Bae, Yoon Hyeok;Kim, Moo-Hyun
    • Journal of Ocean Engineering and Technology
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    • v.29 no.3
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    • pp.255-262
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    • 2015
  • The present study developed a numerical simulation tool for the coupled dynamic analysis of multiple turbines on a single floater (or Multiple Unit Floating Offshore Wind Turbine (MUFOWT)) in the time domain, considering the multiple-turbine aero-blade-tower dynamics and control, mooring dynamics, and platform motions. The numerical tool developed in this study was designed based on and extended from the single-turbine analysis tool FAST to make it suitable for multiple turbines. For the hydrodynamic loadings of floating platform and mooring-line dynamics, the CHARM3D program developed by the authors was incorporated. Thus, the coupled dynamic behavior of a floating base with multiple turbines and mooring lines can be simulated in the time domain. To investigate the effect of asymmetric aerodynamic loading on the global performance and mooring line tensions of the MUFOWT, one turbine failure case with a fully feathered blade pitch angle was simulated and checked. The aerodynamic interference between adjacent turbines, including the wake effect, was not considered in this study to more clearly demonstrate the influence of the asymmetric aerodynamic loading on the MUFOWT. The analysis shows that the unbalanced aerodynamic loading from one turbine in MUFOWT may induce appreciable changes in the performance of the floating platform and mooring system.

Proposal for a Wavelength-Independent Optical Sensor Based on an Asymmetric Mach-Zehnder Interferometer

  • Luo, Yanxia;Yin, Rui;Ji, Wei;Huang, Qingjie;Gong, Zisu;Li, Jingyao
    • Current Optics and Photonics
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    • v.4 no.6
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    • pp.558-565
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    • 2020
  • A wavelength-independent optical sensor based on an asymmetric Mach-Zehnder interferometer (AMZI) is proposed. The optical sensor based on an AMZI is very sensitive to wavelength, and wavelength drift will lead to measurement error. The optical sensor is compensated to reduce its dependence on wavelength. The insensitivity of the optical sensor to wavelength mainly depends on the compensation structure, which is composed of an AMZI cascaded with another AMZI and can compensate the wavelength drift. The influence of wavelength drift on the optical sensor can be counteracted by carefully designing the size parameters of the compensation structure. When the wavelength changes from 1549.9 nm to 1550.1 nm, the error after compensation can be lower than 0.066%. Furthermore, the effect of fabrication tolerance on compensation results is analyzed. The proposed compensation method can also be used to compensate the drift of other parameters such as temperature, and can be applied to the compensation of other interference-based optical devices.