• Imaging Science in Dentistry
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• v.37 no.1
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• pp.45-51
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• 2007

Purpose : This study aimed to identify the range of normal facial asymmetry using three-dimensional CT and to develop a simple method of diagnosis of facial asymmetry. Materials and Methods : Twenty eight adults with normal occlusion (16 males and 12 females; mean age 24 years and 1 month) were selected whose faces were assessed to be symmetric by an orthodontist. Three-dimensional reconstructions were obtained utilizing spiral CT scans and an oral and maxillofacial radiologist evaluated nineteen anatomic landmarks in three-dimensional coordinates. Facial asymmetry index of each landmark was caluculated. Results : The range of normal facial asymmetry of each landmark was identified using mean and standard deviation of facial asymmetry index. Conclusions : The range of normal facial asymmetry identified in this study may be used as a diagnostic standard for facial asymmetry analysis.

• Asia-Pacific Journal of Business
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• v.14 no.1
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• pp.351-364
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• 2023

Purpose - This study examines the effects of Dubai oil price and the volatility on the asymmetry of domestic gasoline price adjustment. Additionally, the study investigates the effects of "Altteul" gas-station and tax-cut policies on asymmetry. Design/methodology/approach - Firstly, the study calculates proxies for asymmetry and volatility of each window(every 3-month) by error-correction model and GARCH(1, 1) using daily domestic gas price and Dubai oil price from 2008/04/15 to 2022/12/31. Secondly, the study investigates the effects of the increasing rate of Dubai oil price, volatility, "Altteul" gas-station and tax-cut policies on asymmetry. The autoregressive distributed lag regression model is employed for estimations. Findings - The study finds that changes in the increasing rate of Dubai oil price and both types of volatility of Dubai oil price increase asymmetry. While "Altteul" gas-station and tax-cut policies decrease asymmetry. Additionally, the study fails to find that asymmetry in the Korean gasoline market in the estimation with total observations. Research implications or Originality - An increase in Dubai oil price volatility means an increase in cost uncertainty for gas-station owners. Since cost uncertainty is a kind of financial risk, the increase in volatility reinforces the asymmetry. The study provides supporting evidence for the idea.

• The korean journal of orthodontics
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• v.27 no.3 s.62
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• pp.445-456
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• 1997

This study was designed to examine the dental asymmetry in person with facial asymmetry and to examine the relationship between the degree of mandibular deviation and asymmetry of maxillary dental arch. The sample!, were divided to asymmetry group and normal group. The asymmetry group consisted of 21 subjects(6 males and 15 females) and their mean age was 23.5 years. The normal group consisted of 20 subjects(10 males and 10 females) and their mean age was 18.6 years. Anteroposterior, transverse position of all maxillary teeth except 3rd molars, vortical position of maxillary 1st molars, and angulation of central incisors were measured. The anterioposterior and transverse positions of teeth were measured on the maxillary dental casts, the vertical position of maxillary 1st molars and angulation of maxillary incisors were measured on posteroanterior cephalometric radiographs. The data were analyzed to examine whether significant asymmetries existed in each of the asymmetry and normal groups. The results of this study were as follows : 1. In the asymmetry group, the correlation between the degree of mandibular deviation and that of 3-dimensional dental asymmetry was not so high. 2. In the asymmetry group, the teeth in deviated side were more laterally positioned than that of undeviated side. There were differences in the anteroposterior position of maxillary 1st and 2nd molars and the angulation of maxillary central incisors. 3. In the asymmetry group, the transverse asymmetry was larger in the posterior teeth rather than in the anterior teeth and larger than the anteroposterior asymmetry.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.30 no.2
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• pp.108-120
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• 2004

Object : Patients with facial asymmetry accompanying mandibular prognathism have various causes and clinical features. So, it is difficult to find a satisfactory treatment method functionally and esthetically. Every traditional classification and interpretation to find etiopathogenesis and/or to establish ideal surgical modality has many limitations because it can't be applied simply to various conditions of patients with facial asymmetry accompanying mandibular prognathism. Therefore, we employ a new classification to interpret more details of the morphologic change of mandible and the spatial change of mandible and maxilla. Materials and Methods : Using panoramic X-ray films, PA cephalograms and submentovertex films of 126 patients diagnosed with facial asymmetry accompanying mandibular prognathism as resources, the following results were gathered after analyzing each characteristics through distributing the patterns according to the morphological mandibular asymmetry and mandibular and maxillary spatial asymmetry. Results : Almost frequency of morphological mandibular asymmetry was shown. In case of condyle-ramus elongation and body elongation group, it's frequency was the highest. Higher frequency of compensating vertical growth was shown on the side of over growing maxilla in case of vertical length difference between left and right condyle-ramus. On the other hand, higher frequency of no compensating vertical growth difference between left and right side was shown in case of no vertical length difference in condyle-ramus. Spatial mandibular asymmetry generally occurred when there was no morphological mandibular asymmetry. Correlation between condyle length difference and condyle-ramus length difference between left and right side was very high, but correlation between condyle length difference and body length difference, and correlation between condyle length difference and body vertical length difference was low. Conclusion : In case of patients with facial asymmetry accompanying mandibular prognathism, it is suggested that various pattern of facial asymmetry is occurred by the independent growth of each unit rather than dependent growth of other unit by major growth unit abnormality. Due to the untypical pattern and the various asymmetry occurring according to the changes of each mandibular growth unit, it is considered that an appropriate surgical method should be searched based on the accurate recognition of the each pattern for patients with facial asymmetry accompanying mandibular prognathism.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.23 no.1
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• pp.56-63
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• 2014

This paper provides a comprehensive study on the Sommerfeld phenomena in an asymmetric rotor with a nonideal power supply. An analytical approach is employed by deriving the equations of motion in a nondimensional form. The system parameters, including the asymmetry, external and internal damping, and motor power, are chosen to find their effects on the characteristics of the Sommerfeld phenomena and critical behavior around resonance. Results show that the rotor asymmetry suppresses the Sommerfeld phenomena and helps pass through resonance if the asymmetry is small. However, it is observed that the opposite effects exist in case of a large asymmetry. It is also found that the effects of external damping on the Sommerfeld phenomena are similar to those of the asymmetry, whereas internal damping has less effects than external damping and the asymmetry. By performing numerical simulations, four types of critical behavior are identified from the viewpoints of the stability and the passage through resonance.

• Journal of Environmental Science International
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• v.31 no.12
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• pp.1117-1126
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• 2022

This study analyzed the effect of Corporate Social Responsibility and ESG (Environmental, Social and Governance) score on information asymmetry from the perspective of investors, who are important stakeholders of the company. For KOSPI-listed companies from 2017 to 2020, the effect of ESG overall score and each item score (E, S, G) on the bid-ask spread, which is a proxy for information asymmetry, was confirmed. The results are as follows. First, the increase in corporate CSR activities resulted in lowering information asymmetry of investors. It was found that the higher the ESG score, an indicator of CSR activity, the lower the bid-ask spread, which is a proxy variable for information asymmetry. Second, as a result of analysis using ESG scores for each section, information asymmetry decreased as companies with higher scores in the environmental (E) and social (S) aspects, while the governance (G) score did not have a statistically significant effect. The analysis confirmed that corporate CSR activities can contribute to improving market efficiency by resolving information asymmetry of investors and convergence of the stock market into a state of equilibrium. This means that the company's CSR activities are reflected in the investment decision-making, which suggests that the company should consider the investor as a stakeholder in decision-making related to CSR activities.

• The korean journal of orthodontics
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• v.48 no.6
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• pp.357-366
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• 2018

Objective: The purpose of this study was to analyze the transverse dental compensation in reference to the maxillary and mandibular basal bones using cone-beam computed tomography (CBCT) and evaluate the correlations between transverse dental compensation and skeletal asymmetry variables in patients with skeletal Class III malocclusion and facial asymmetry. Methods: Thirty patients with skeletal Class I (control group; 15 men, 15 women) and 30 patients with skeletal Class III with menton deviation (asymmetry group; 16 men, 14 women) were included. Skeletal and dental measurements were acquired from reconstructed CBCT images using OnDemand3D 1.0 software. All measurements were compared between groups and between the deviated and nondeviated sides of the asymmetry group. Correlation coefficients for the association between skeletal and dental measurements were calculated. Results: Differences in the ramus inclination (p < 0.001), maxillary canine and first molar inclinations (p < 0.001), and distances from the canine and first molar cusp tips to the midmaxillary or midmandibular planes (p < 0.01) between the right and left sides were significantly greater in the asymmetry group than in the control group. In the asymmetry group, the ramus inclination difference (p < 0.05) and mandibular canting (p < 0.05) were correlated with the amount of menton deviation. In addition, dental measurements were positively correlated with the amount of menton deviation (p < 0.05). Conclusions: Transverse dental compensation was correlated with the maxillary and mandibular asymmetry patterns. These results would be helpful in understanding the pattern of transverse dental compensation and planning surgical procedure for patients with skeletal Class III malocclusion and facial asymmetry.

• The Journal of Churna Manual Medicine for Spine and Nerves
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• v.17 no.2
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• pp.81-89
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• 2022

Objectives This report aimed to investigate the possibility of correcting facial asymmetry using cervical Chuna manipulation treatment and functional cerebrospinal technique and introduce meaningful additional improvement of systemic symptoms of non-surgical Korean medicine treatments through three case studies. Methods Three patients with facial asymmetry were treated using Korean medicine treatments. The effects of the treatments were all measured using photographs, lateral cephalograms, and whole-body radiogram and Likert scale. Results After Korean medicine treatment, there were significant correction effects of asymmetry in photography, cephalography, and whole-body radiogram and meaningful score of Likert scale. Conclusions This study suggested that Korean medicine treatments may be effective in facial asymmetry. Improving muscular asymmetry, including soft tissue asymmetry and functional asymmetry, has meaningful effects on maintaining an overall balance of the body. Facial asymmetry should be treated by making an alignment of the whole body and there should be further well-designed, randomized, and placebo-controlled trials to verify these results.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.05a
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• pp.941-944
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• 2005

Asymmetry of rotor systems is an important factor for identification of dynamic characteristics including the stability and response of rotors and for condition monitoring. In this work, asymmetry of rotors is identified by applying curve-fitting method to the directional frequency response functions (dFRFs), which are known as a powerful tool for detecting the presence and degree of asymmetry. This method minimizes least square error between analytical and measured dFRFs by iteratively updating physical parameters associated with rotor asymmetry. The effectiveness of the identification method is demonstrated by experiments with a laboratory test rotor.

• Journal of Astronomy and Space Sciences
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• v.24 no.2
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• pp.91-98
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• 2007

The existence of the North-South asymmetry of the solar activity is widely accepted even though the phenomenon is not yet satisfactorily understood. We have studied the temporal variations in the North-South asymmetry of the sunspot area during the period from May in 1874 to April in 2007. The combined data have been examined for periodicity in the solar activity North-South asymmetry. We have found that (i) solar northern and southern hemispheres show an asymmetric behavior, in terms of a sunspot area, (ii) sunspot areas in northern and southern hemispheres show clearly the 11 year periodicity when they were analyzed separately, as they do when analyzed together, (iii) in addition to the general 11 year periodicity in both northern and southern hemisphere solar activities, there are also noticeable shorter periodicities other than the 11 year periodicity in the asymmetry in North-South activity. Finally, we conclude by pointing out the importance of studying the North-South asymmetry of the solar activity.